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1. The 367 nm photochemistry of chlorine dioxide in and on amorphous ice.
Anderson, L. D.; Roberts, J. T.; Grassian, V. H. (Department ofChemistry, University of Iowa, Iowa City, IA 52246, USA). Proc.SPIE-Int. Soc. Opt. Eng., 3272(Laser Techniques for Surface ScienceIII), 286-295 (English) 1998 SPIE-The International Society for OpticalEngineering. CODEN: PSISDG. ISSN: 0277-786X. DOCUMENT
TYPE: Journal CA Section: 74 (Radiation Chemistry, Photochemistry,and Photographic and Other Reprographic Processes)
The 367 nm photochem. of chlorine dioxide, OClO, in and on thin films of amorphous ice at T = 100 K has been investigated. Reflection Absorption IR Spectroscopy (RAIRS) was used to probe the photoproducts formed in and on amorphous ice films upon 367 nm irradn. Under dil. conditions, 367 nm irradn. of OClO in amorphous ice results in the formation of the isomer, chlorine superoxide, ClOO. Under more concd. conditions, in which OClO clusters are present, 367 nm irradn. OClO results in an addnl. photoproduct chloryl chloride, Cl-ClO2. Irradn. of OClO adsorbed on ice results in the formation of a single chlorine-contg. photoproduct identified as Cl-ClO2. Similarities in the photoreactivity of concd. amorphous ice films contg. OclO clusters and OClO adsorbed on ice suggest that OClO clusters may play a role in ice surface photochem.
2. Use of FTIR transmittance, DRIFT, and FT-Raman spectroscopies for evaluation of delignification capability and selectivity of bleaching chemicals.
Sukhov, D. A.; Fedorov, A. V.; Derkacheva, O. Yu.; Butko, Yu. G.; Keranen, E.; Huttunen, H. (State University of Plant Polymers, St.Petersburg 198095, Russia). Adv. Lignocellul. Chem. Ecol. Friendly Pulping Bleaching Technol., Eur. Workshop Lignocellul. Pulp, 5th, 69-71. University of Aveiro: Aveiro, Port. (English) 1998. CODEN: 66TZAG. DOCUMENT TYPE: Conference CA Section: 43 (Cellulose, Lignin, Paper, and Other Wood Products)
Delignification capability and selectivity of Cl- and O-based chems. In bleaching of sulfite and kraft softwood and kraft hardwood pulps were evaluated by chem. (kappa no.) and optical methods. Delignification capability and selectivity evaluated by kappa no. were mostly lower than those given by optical measurements. ClO2 and Cl bleaching had the highest delignification selectivity for softwood pulps and H2O2 for kraft hardwood pulp.
3. Turing instability in a boundary-fed system.
Setayeshgar, S.; Cross, M. C. (Condensed Matter Physics 114-36,
California Institute of Technology, Pasadena, CA 91125, USA). Phys.
Rev. E: Stat. Phys., Plasmas, Fluids, Relat. Interdiscip. Top., 58(4),
4485-4500 (English) 1998 American Physical Society. CODEN:
PLEEE8. ISSN: 1063-651X. DOCUMENT TYPE: Journal CA Section:
67 (Catalysis, Reaction Kinetics, and Inorganic Reaction Mechanisms)
Section cross-reference(s): 22, 65
The formation of localized structures in the chlorine
dioxide-iodine-malonic acid (CDIMA) reaction-diffusion system is
investigated numerically using a realistic model of this system. We
analyze the one-dimensional patterns formed along the gradients
imposed by boundary feeds, and study their linear stability to
symmetry-breaking perturbations (Turing instability) in the plane
transverse to these gradients. We establish that an often-invoked
simple local linear anal. that neglects longitudinal diffusion is
inappropriate for predicting the linear stability of these patterns. Using
a fully nonuniform anal., we investigate the structure of the patterns
formed along the gradients and their stability to transverse Turing
pattern formation as a function of the values of two control parameters:
the malonic acid feed concn. and the size of the reactor in the
dimension along the gradients. The results from this investigation are
compared with existing expts.
4.Validation of a mill-specific job-exposure matrix in the British Columbia pulp and paper industry.
Astrakianakis, George; Band, Pierre R.; Le, Nhu; Bert, Joel L.;
Janssen, Bob; Svirchev, Laurence; Tang, Clement; Anderson, Judith T.
L.; Keefe, Anya R. (Cancer Control Research Unit, British Columbia
Cancer Agency, Vancouver, BC V5Z 4E6, Can.). Appl. Occup.
Environ. Hyg., 13(9), 671-677 (English) 1998 Elsevier Science Inc.
CODEN: AOEHE9. ISSN: 1047-322X. DOCUMENT TYPE: Journal
CA Section: 59 (Air Pollution and Industrial Hygiene) Section
cross-reference(s): 43
Job--exposure matrixes (JEMs) are being used to organize
occupational exposure assessments for a nested case-- control study
of British Columbia pulp and paper workers. To validate the methodol.
used to create the JEMs, the ests. from the first mill studied were
compared with personal measurements subsequently collected from
that site. In total, 1678 samples were collected from workers to assess
their exposure to five chems.; these samples characterized both
shift-long av. and short-term high level exposures. The comparison
indicated that the ests. were effective at predicting which job titles were
exposed to carbon monoxide, calcium oxide, and wood dust, but less
so for chlorine dioxide. Ests. were also effective at predicting which job
titles were unexposed to calcium oxide, but less so for carbon
monoxide, chlorine dioxide, and wood dust. The differing degrees of
agreement between the ests. and measurements can be partly
explained by the phys. characteristics of each chem. and process
changes at the mill. This validation generated refinements to the JEM
methodol. Originally there were two parameters for each exposure est.:
concn. and proportion of time exposed. The short-term high level
exposures that were originally incorporated into the concn. parameter
are now assessed independently. Also, proportion of time exposed
was revised from four categories to three to reflect the time spent in
exposed environments by the three categories of workers: operators,
field workers, and laborers. The sampling results identified that factors
such as process upsets, tasks, and location can affect the variability of
exposures. The necessity of validation and the benefit of mill-specific
over industry-specific retrospective exposure assessments are clearly
demonstrated.
5.Analysis of the delocalization in the topological theory of chemical bond.
Noury, S.; Colonna, F.; Savin, A.; Silvi, B. (Lab. Chimie Theorique,
Univ. Pierre et Marie Curie, Paris 75252, Fr.). J. Mol. Struct., 450(1-3),
59-68 (English) 1998 Elsevier Science B.V. CODEN: JMOSB4.
ISSN: 0022-2860. DOCUMENT TYPE: Journal CA Section: 65
(General Physical Chemistry)
The topol. anal. of the gradient field of the electron localization function
provides a convenient theor. framework for the partition of the mol.
space into basins of attractors having a clear chem. meaning. The
basin populations are evaluated by integrating the one-electron d. over
the basins. The variance of the basin population provides a measure
of the delocalization. The behavior of the core C(X) and protonated
valence basins V(X, H) populations were investigated. The anal. of the
population variance in terms of cross-contributions is presented for
arom. and antiarom. systems, hypervalent mols. and hydrogen-bonded
complexes. For hypervalent mols. this anal. emphasizes the
importance of the ionic resonance structures.
6. Formation of herbicide degradation byproducts during groundwater disinfection: an LC-MS investigation.
Lopez, A.; Mascolo, G.; Tiravanti, G.; Passino, R. (Consiglio Nazionale
delle Ricerche, Istituto di Ricerca Sulle Acque, Bari 5-70123, Italy). J.
Anal. Chem., 53(9), 856-860 (English) 1998 MAIK
Nauka/Interperiodica Publishing. CODEN: JACTE2. ISSN:
1061-9348. DOCUMENT TYPE: Journal CA Section: 61 (Water)
Section cross-reference(s): 5, 80
The chem. structures of several byproducts of disinfection (i.e., with
sodium hypochlorite and chlorine dioxide) of aq. streams contg. two
herbicides (Terbutryn and Isoproturon) widely used in agriculture and
frequently found in groundwaters. All reactions were carried out under
the controlled exptl. conditions: T = 25*; pH 7; tc (contact time) = 48 h;
and herbicide-disinfectant concn. ratio, (0.05 * 10-3 M)/(1 * 10-3 M).
Under such conditions, Terbutryn reacted with chlorine dioxide much
more slowly than with sodium hypochlorite, whereas the reverse trend
was obsd. for Isoproturon. Reaction byproducts were detected by
HPLC and identified by HPLC-MS; however, for Isoproturon, the
identification is unfinished. Isoproturon reacts to form six different
byproducts: four with NaClO and two with ClO2. Exptl. evidence
supported the hypothesis that Isoproturon reacts with the selected
disinfectants in two different ways. This herbicide presumably
undergoes oxidn. by ClO2 and substitution by NaClO. Terbutryn is
instead oxidized by both disinfectants. In particular this herbicide forms
four identified derivs. with NaClO: the sulfoxide, the sulfone, the
sulfonate ester, and the hydrolysis product, whereas it forms only the
sulfoxide deriv. with ClO2.
7. Method and apparatus for removal of residual chlorine dioxide gas
from indoor air by reductive compounds.
Ogawa, Katsutoshi; Kikuchi, Koji (Chisso Corp.; National Federation
of Agricultural Co-Operative Assoc., Japan). Jpn. Kokai Tokkyo Koho
JP 10258215 A2 29 Sep 1998 Heisei, 6 pp. (Japanese). (Japan).
CODEN: JKXXAF. CLASS: ICM: B01D053-68. ICS: B01D053-77;
B01D053-14; B01D053-34. APPLICATION: JP 98-17927 14 Jan
1998. PRIORITY: JP 97-17589 14 Jan 1997. DOCUMENT TYPE:
Patent CA Section: 59 (Air Pollution and Industrial Hygiene)
The method is carried out by using an absorbing liq. (e.g., contg.
DMSO) to absorb residual chlorine dioxide from the air after
disinfection, then passing the used liq. through a column filled with
reductive solid (e.g., activated carbon) for removing the chlorine
dioxide from the liq. to be reuse.
8. Laser photolysis of chlorine dioxide in water.
Thogersen, J.; Thomsen, C. L.; Poulsen, J.-Aa.; Keiding, S. R. (Kemisk
Inst., Aarhus Univ., Den.). Dan. Kemi, 79(8), 35-39 (Danish) 1998
Teknisk Forlag. CODEN: DAKEAT. ISSN: 0011-6335. DOCUMENT
TYPE: Journal CA Section: 59 (Air Pollution and Industrial Hygiene)
The photolysis of ClO2 into ClO and O using laser spectroscopy was
studied on a femtosecond time scale. The ClO2 soln. was formed from
a mixt. of NaClO2 and K2S2O8 and a few drops of water. The ClO2(g)
was collected in a stream of high-purity N, the mixt. passed through a
NaClO2 soln. to remove Cl2, and through distd. water to obtain a ClO2
stable soln. The photolysis was carried out with a Ti-sapphire laser.
The transient absorption spectrum of ClO2, the absorption spectrum of
the photolysis products, and the caging effect are presented. The
examples illustrate that the understanding of chem. reaction dynamics
in liqs. are a first and foremost question of understanding the
interaction between dissolved mols. and the solvent.
9. Antimicrobial composition and method of use.
Kross, Robert D. (USA ). U.S. US 5820822 A 13 Oct 1998,7 pp.
(English). (United States of America). CODEN: USXXAM. CLASS:
ICM: A61K007-20. NCL: 422037000. APPLICATION: US 96-738006
25 Oct 1996. DOCUMENT TYPE: Patent CA Section: 62 (Essential
Oils and Cosmetics) Section cross-reference(s): 63
An antimicrobial and deodorizing compn. is disclosed, which includes
an aq. soln. having at least one acid-inducing metal salt and a metal
chlorite and no protic acid. The aq. soln. has a pH less than about 7.
The acidity-inducing metal salt, preferably, includes an iron cation, an
aluminum cation, a gadolinium cation, a vanadium cation, a zirconium
cation or a zinc cation, and anions sufficient for rendering the metal salt
elec. neutral and water-sol. The metal chlorite may, preferably, be
sodium chlorite. Various methods for use of the compn. are also
disclosed. Microcapsules contg. 35 % aq. sodium chlorite were
suspended in a gel compn. contg. aluminum chlorhydroxide (15 %
soln.) 10 g, ethanol 12 mL, propylene glycol 3 g, NaOH 0.75 g, stearic
acid 5.25 g, and water 42 g to give a deodorant stick.
10. Modification of sorption characteristics in aquifers to improve
groundwater remediation.
Smith, Gregory; Dumdei, Bruce; Jurka, Valdis (ENSR Consulting and
Engineering, Westmont, IL, USA). Phys., Chem., Therm. Technol., Int.
Conf. Rem. Chlorinated Recalcitrant Compd., 1st, 193-198. Edited by:
Wickramanayake, Godage B.; Hinchee, Robert E. Battelle Press:
Columbus, Ohio. (English) 1998. CODEN: 66RLAW. DOCUMENT
TYPE: Conference CA Section: 61 (Water) Section cross-reference(s):
19, 60
The authors adapted oil well stimulation technologies (U.S. Patent
4,871,022) to groundwater remediation. Chlorine dioxide has been
used in the oil industry as a bactericide, to remove sludge, improve
formation permeability and improve oil prodn. We utilized chlorine
dioxide in the field over a period ranging from May 1996 to Mar. 1997
to temporarily alter Eh characteristics of the aquifer matrix and its
response to pH, thereby modifying its sorptive characteristics. The
applications were performed in the field at a site undergoing full-scale
soil and groundwater remediation for trichloroethene and
1,1,1-trichloroethane that has been underway since 1991, using steam
flooding and simultaneous enhanced biotransformation (U.S. Patent
5,279,740). The site is a former electronics manufg. plant located in
the northern suburbs of Chicago, Illinois. Dense non-aq. phase liqs.
(DNAPL) had been removed from the subsurface with the exception of
four areas. Two of these areas appeared to have significant oils
(cutting oils, hydraulic oils) which were suspected to be limiting the
DNAPL removal. It was decided to apply chlorine dioxide for removing
oily materials from subsurface formations to aid remediation. After
injection of chlorine dioxide, we obsd. concns. of 1,1,1-trichloroethane
in groundwater increase approx. two-fold in response because of
desorption and dissoln. of the compds. Net concns. after treatment
decrease by one order of magnitude.
11. Effects and mechanisms involved in preoxidation and particle
separation processes.
Jekel, Martin R. (Department of Water Quality Control, Technical
University of Berlin, Berlin D-10623, Germany). Water Sci. Technol.,
37(10, Pretreatment for Separation), 1-7 (English) 1998 Elsevier
Science Ltd. CODEN: WSTED4. ISSN: 0273-1223. DOCUMENT
TYPE: Journal; General Review CA Section: 61 (Water)
A review with 40 refs. concerning the effect and mechanisms involved
in pre-oxidn. and particle sepn. processes during water purifn. is given.
Topics discussed include: pre-oxidn. effect on particle removal from
surface water; and proposed mechanisms related to pre-oxidn. effects.
Effects are reported for pre-oxidn. by O3, Cl2, ClO2, permanganate, and
chloramines.
12. New process for elemental chlorine-free (ECF) bleaching of various
types of kraft pulps.
Sergeev, A. D.; Petrenev, V. A.; At'man, O. P. (AO " SibNII TSBP",
Russia). Tsellyul., Bum., Karton, (5-6), 5-6 (Russian) 1998 Tsellyuloza,
Bumaga, Karton. CODEN: TBKAEY. ISSN: 0869-4923. DOCUMENT
TYPE: Journal CA Section: 43 (Cellulose, Lignin, Paper, and Other
Wood Products)
Kraft pulps were subjected to bleaching according to the following
scheme: alkali treatment-bleaching with ClO2 at simultaneous treatment
with EDTA chelating agent - bleaching with H2O2. The role of EDTA
was to bind transition metal ions which interfere with H2O2 bleaching.
Addn. of *10 kg EDTA per ton pulp resulted in an increase of the
brightness degree of the bleached pulp by 1.3-3.0% at simultaneous
increase of the mech. strength of the pulp.
13. Nutrients in salmon and red grouper fillets as affected by chlorine
dioxide (ClO2) treatment.
Kim, Jeongmok; Du, Wen-Xian; Otwell, W. Steven; Marshall, Maurice
R.; Wei, Cheng-I. (Food Science & Human Nutrition Dept., Univ. of
Florida, Gainesville, FL 32611-0370, USA). J. Food Sci., 63(4),
629-633 (English) 1998 Institute of Food Technologists. CODEN:
JFDSAZ. ISSN: 0022-1147. DOCUMENT TYPE: Journal CA Section:
17 (Food and Feed Chemistry)
The effect of chlorine dioxide (ClO2) treatment on nutrients of seafood
was studied using Atlantic salmon (Salmo salar) and red grouper
(Epinephelus morio) with five vols. (1:5, wt./vol.) of aq. ClO2 at 20, 40,
100, and 200 ppm ClO2 in 3.5% brine for 5 min. Compared to
nontreated controls, treatment of salmon and red grouper with ClO2
solns. in brine did not significantly change the contents of protein, fat,
moisture, niacin, calcium, iron, phosphorus, or potassium. However,
such treatment with brine or ClO2 solns. in brine caused a significant
redn. in thiamin content in both species, but only riboflavin was reduced
significantly in red grouper, possibly due to the solubilization effect of
salt on the vitamins.
14. Femtosecond pump-probe studies of chlorine dioxide photochemistry
in water and acetonitrile.
Philpott, Matthew J.; Hayes, Sophia C.; Reid, Philip J. (Department of
Chemistry, Box 351700, University of Washington, Seattle, WA 98195,
USA). Chem. Phys., 236(1-3), 207-224 (English) 1998 Elsevier
Science B.V. CODEN: CMPHC2. ISSN: 0301-0104. DOCUMENT
TYPE: Journal CA Section: 74 (Radiation Chemistry, Photochemistry,
and Photographic and Other Reprographic Processes)
The reaction dynamics of chlorine dioxide (OClO) dissolved in water
and acetonitrile are investigated using femtosecond pump-probe
spectroscopy. The change in optical d. following photoexcitation of
OClO at 400 nm is monitored at 12 wavelengths ranging from 267 to
900 nm. The dynamics obsd. at 267 and 400 nm demonstrate that the
geminate recombination quantum yield of the primary ClO and O
photofragments to reform ground-state OClO is reduced by a factor of
six in acetonitrile relative to water. Calcns. are presented that model
the contribution of vibrationally excited OClO formed by geminate
recombination to the pump-probe dynamics. Comparison of the exptl.
and computational results demonstrates that a portion of the dynamics
can be attributed to vibrationally excited OClO. However, the optical-d.
changes obsd. between 700 and 900 nm are similar in magnitude for
both solvents, suggesting that another species not produced by
geminate recombination is responsible for these dynamics. The
appearance and relaxation kinetics in acetonitrile are significantly
slower than in water demonstrating the solvent dependence of
photoproduct formation and ground-state vibrational relaxation.
Reasons for this dependence including Coulombic solvent-solute
interactions and intermol. hydrogen bonding are discussed.
15. Germicidal activity of a chlorous acid-chlorine dioxide teat dip and a
sodium chlorite teat dip during experimental challenge with
Staphylococcus aureus and Streptococcus agalactiae.
Boddie, R. L.; Nickerson, S. C.; Adkinson, R. W. (Mastitis Research
Laboratory, Hill Farm Research Station, Louisiana Agricultural
Experiment Station, Louisiana State University Agricultural Center,
Homer 71040, USA). J. Dairy Sci., 81(8), 2293-2298 (English) 1998
American Dairy Science Association. CODEN: JDSCAE. ISSN:
0022-0302. DOCUMENT TYPE: Journal CA Section: 63
(Pharmaceuticals) Section cross-reference(s): 1
Three postmilking teat dips were tested for efficacy against
Staphylococcus aureus and Streptococcus agalactiae in two sep.
studies using exptl. challenge procedures that were recommended by
the National Mastitis Council. The first study evaluated a barrier teat
dip product contg. chlorous acid-chlorine dioxide as the germicidal
agent, and the second study evaluated a sodium chlorite product with a
barrier component as well as a sodium chlorite product without a
barrier component. The chlorous acid-chlorine dioxide teat dip
reduced new intramammary infections (IMI) caused by Staph. aureus by
91.5% and reduced new IMI caused by Strep. agalactiae by 71.7%.
The barrier dip contg. sodium chlorite reduced new IMI caused by
Staph. aureus and Strep. agalactiae by 41.0 and 0%, resp. The
nonbarrier dip contg. sodium chlorite reduced new IMI caused by
Staph. aureus by 65.6% and reduced new IMI caused by Strep.
agalactiae by 39.1%. Teat skin and teat end conditions were
evaluated before and after the second study; no deleterious effects
among dipped quarters compared with control quarters were noted for
the two sodium chlorite products.
16. The effect of photochemical dissociation on downwind chlorine dioxide
plume concentrations.
Michalowicz, Robert; Alp, Ertugrul (BOVAR Environmental, Toronto, ON
M3H 2V2, Can.). Proc., Annu. Meet. - Air Waste Manage. Assoc.,
90th, MP801/1-MP801/14 (English) 1997 Air & Waste Management
Association. CODEN: PAMEE5. ISSN: 1052-6102. DOCUMENT
TYPE: Journal; (computer optical disk) CA Section: 59 (Air Pollution
and Industrial Hygiene) Section cross-reference(s): 43
The pulp and paper industry handles toxic gases which may present an
inherent hazard to the safety of the general public in the surrounding
area. One such toxic gas that may pose a hazard is chlorine dioxide.
Spills of chlorine dioxide soln. result in the gassing off of toxic clouds of
chlorine dioxide. Under daytime dry conditions, chlorine dioxide
decomps. photolytically to form chlorine and oxygen and intermediates,
chlorine trioxide and chlorine hexoxide. Air dispersion modeling of
chlorine dioxide releases which does not properly account for its
photochem. decompn. will lead to overly conservative hazard zone ests.
Under these conditions, risk control measures and emergency
response evacuation zones based on such ests. will be unnecessarily
expensive, perhaps prohibitive. This paper investigates the photolytic
rate of dissocn. of chlorine dioxide under various atm. conditions. It
was found that modeling based on the decompn. of chlorine dioxide
gas, resulted in downwind distances to TLV-Short Term Exposure
Limits which are considerably shorter than modeling based on chlorine
dioxide dispersion with no decompn.
17. Oxygen delignification of chemical pulp.
Jin, Yongcan; Lee, Zhongzheng; Tai, Diesheng (College of Chem.
Engineering, Nanjing Forestry University, Nanjing 210037, Peop. Rep.
China). Xianweisu Kexue Yu Jishu, 6(2), 5-14 (Chinese) 1998
Guangzhou Huaxue Yanjiuso. CODEN: XKYJFZ. ISSN: 1004-8405.
DOCUMENT TYPE: Journal CA Section: 43 (Cellulose, Lignin, Paper,
and Other Wood Products)
The mechanism, reaction kinetics and affected factors of oxygen
delignification, and the pretreatment methods and their properties
before oxygen delignification were introduced. The tech.
characteristics of oxygen delignification were also concluded and
evaluated.
18. Dividing Blobs, Chemical Flowers, and Patterned Islands in a
Reaction-Diffusion System.
Davies, P. W.; Blanchedeau, P.; Dulos, E.; De Kepper, P. (Centre de
Recherche Paul Pascal/CNRS, Universite Bordeaux I, Pessac
F-33600, Fr.). J. Phys. Chem. A, 102(43), 8236-8244 (English) 1998
American Chemical Society. CODEN: JPCAFH. ISSN: 1089-5639.
DOCUMENT TYPE: Journal CA Section: 67 (Catalysis, Reaction
Kinetics, and Inorganic Reaction Mechanisms) Section
cross-reference(s): 22, 65
In an one-side-fed open spatial reactor operated with the chlorine
dioxide-iodine-malonic acid reaction in the presence of polyvinyl alc.,
we systematically studied the growth dynamics of Turing patterns after
a supercrit. parameter change. We describe different modes of
propagation of the patterned state in an absolutely unstable uniform
state, among which are a spot division and a finger splitting mode. We
attribute these peculiar growth modes to the existence of two different
uniform states and to a morphol. instability of a propagating front linking
these two states. In regions where bistability between the Turing state
and a uniform state is obtained, the interface between the patterned
state and the uniform state can be brought to a halt and thus localized
patterned states are obsd.
19. Accuracy assessment of the ROHF-CCSD(T) calculations of dipole
moments of small radicals.
Urban, Miroslav; Neogrady, Pavel; Raab, Juraj; Diercksen, Geerd H. F.
(Department of Physical Chemistry, Faculty of Sciences, Comenius
University, Bratislava SK-842 15, Slovakia). Collect. Czech. Chem.
Commun., 63(9), 1409-1430 (English) 1998 Institute of Organic
Chemistry and Biochemistry, Academy of Sciences of the Czech
Republic. CODEN: CCCCAK. ISSN: 0010-0765. DOCUMENT
TYPE: Journal CA Section: 65 (General Physical Chemistry) Section
cross-reference(s): 76
Dipole moments of a series of radicals, OH, NO, NS, SF, SO, PO, ClO,
CN, LiO, NO2, and ClO2 were calcd. by the Coupled Cluster CCSD(T)
method with the single determinant restricted open shell Hartree-Fock
(ROHF) ref. For all mols. theor. dipole moments were carefully
compared to exptl. values. The size and the quality of the basis set
were systematically improved. Spin adaptation in the ROHF-CCSD(T)
method, largest single and double excitation amplitudes and the T1
diagnostics were considered as indicators in the quality assessment of
calcd. dipole moments. For most mols. the accuracy within 0.01-0.03
D was readily obtained. For ClO and CN the spin adaptation was
necessary - its contribution was as large as 0.03-0.045 D. Large
deviation from expt. is obsd. for OH in its A2S+ excited state (0.135 D)
and esp. for LiO in its 2P ground state (0.22 D). No indication of the
failure of theor. calcns. was found which leads to the conclusion that,
even if there is still a space for the improvement of theor. calcns., exptl.
values should be reconsidered.
20. Chlorine dioxide-based deodorant-disinfectant compositions for air or
water treatment.
Sakuma, Tsunehiro; Isago, Yoshikuni (Car Mate Mfg. Co., Ltd., Japan).
Jpn. Kokai Tokkyo Koho JP 10248911 A2 22 Sep 1998 Heisei, 3 pp.
(Japanese). (Japan). CODEN: JKXXAF. CLASS: ICM: A61L009-01.
APPLICATION: JP 97-72759 11 Mar 1997. DOCUMENT TYPE:
Patent CA Section: 59 (Air Pollution and Industrial Hygiene) Section
cross-reference(s): 61
The title compns. comprise a stabilized ClO2 (hypochlorite salt) aq.
soln., a pH modifier, and a buffer soln. such as NaH2PO4-NaOH aq.
soln.
21. Modeling downwind hazards after an accidental release of chlorine
trifluoride.
Lombardi, Douglas A.; Cheng, Meng-Dawn (Oak Ridge Natl. Lab., Oak
Ridge, TN, USA). Proc., Annu. Meet. - Air Waste Manage. Assoc.,
89th, wp66b02/1-wp66b02/16 (English) 1996 Air & Waste
Management Association. CODEN: PAMEE5. ISSN: 1052-6102.
DOCUMENT TYPE: Journal; (computer optical disk) CA Section: 59
(Air Pollution and Industrial Hygiene) Section cross-reference(s): 71
Chlorine trifluoride (ClF3,) is a chem. compd. used in the gaseous
diffusion process to enrich uranium at two plants, one in Portsmouth,
Ohio and the other in Paducah, Kentucky. Although highly unlikely, a
breach in ClF3, storage cylinders or tanks would result in a potential
release of ClF3, to the atm. The fate of ClF3, once released to the
atm., is a primary concern for plant managers and safety engineers at
the plants because of its extreme toxicity. There are many atm.
dispersion models typically used to model the release of inert airborne
contaminants; however, ClF3 is highly reactive with water vapor in the
atm., and therefore, these models would not accurately predict atm.
concns. of ClF3 downwind of a potential release. Addnl., these models
do not predict the formation of reaction products that also are toxic [i.e.,
hydrogen fluoride (HF) and chlorine dioxide (ClO2)]. An atm. chem.
reaction model was developed to predict release hazards assocd. with
an accidental release of ClF3. Exptl. results indicating that ClF3,
reacts with atm. water vapor in two reaction sequences were
incorporated into the model. The first reaction sequence, termed
excess ClF3, occurs when the molar ratio of ClF3, to water vapor is
greater than two-thirds. The second sequence, termed excess water
vapor, occurs when the molar ratio is less than or equal to two-thirds.
The ClF3, reaction model was incorporated into the AEROPLUME
near-field jet dispersion model which is part of HGSYSTEM (a system
of models used to simulate near- field, heavy-gas, and neutrally buoyant
dispersion from accidental releases). Many simulation exercises were
run to test the model, showing rapid formation of HF and ClO2 after an
atm. release of ClF3. At distances beyond the first several meters from
the release point, HF and ClO2, concns. pose a greater threat to
human health than do ClF3 concns. For most of the simulations, ClF3,
concns. rapidly fall below the IDLH (i.e., within about 20 m). For
releases occurring in ambient conditions with low relative humidity
and/or ambient temp., ClF3 concns. exceed the IDLH up to almost 500
m.
22. 129:264445
Process modifications and source reduction options for reducing VOC,
HAP, and TRS emissions from bleached kraft pulp mills.
Meech, Mark L. (Jacobs-Sirrine Eng., Raleigh, NC, USA). Proc., Annu.
Meet. - Air Waste Manage. Assoc., 89th, wa4d06/1-wa4d06/12
(English) 1996 Air & Waste Management Association. CODEN:
PAMEE5. ISSN: 1052-6102. DOCUMENT TYPE: Journal; (computer
optical disk) CA Section: 59 (Air Pollution and Industrial Hygiene)
Section cross-reference(s): 43
Although the pulp and paper industry has made significant efforts to
reduce emissions and effluent discharges from their mills, recently
proposed cluster rules emphasize the need to consider addnl. methods
to control volatile org. compds. (VOC) and hazardous air pollutant
(HAP) emissions from air- and wastewater-related sources. Some
sources are conducive to the use of emission control or capture
devices, such as non-condensible gas collection systems for high-vol.
low-concn. or low-vol. high-concn. gases, which can be routed to
pollutant destruction devices such as kilns, boilers, or thermal oxidizers.
However, process modifications have increasingly become more
viable options to reduce VOC/HAP emissions simply by reducing the
amt. of pollutant being released from sources. Although economics
must be evaluated, these mills can consider process modifications
such as the use of O delignification systems, the use of H2O2 in their
processes, conversion of the bleaching sequence to an elemental
Cl-free or even a total Cl-free system, as well as conversion of batch
digester systems and their assocd. components to a continuous
digester system. Addnl. process modifications and source redn.
options are available to reduce emissions which can be evaluated
along with emission control device options. If process condensates
and waste streams cannot be reduced through process modifications,
scrubbers or capture systems may be considered. If the mill foresees
being forced to reduce overall VOC/HAP emissions, potential process
modification and optimization approaches are alternatives to emission
control devices which can provide the redns. necessary to bring a mill
into compliance. Various process modifications are discussed and
quantified with respect to potential emission redns. assocd. with their
use, including: ClO2 substitution; O2 delignification; peracids and H2O2
for bleaching applications; and aminal scrubbing.
23. Real-time changes induced by pulsed laser heating in ammonium
perchlorate at static high pressures.
Pangilinan, G. I.; Russell, T. P. (Chemistry Division, Code 6110, Naval
Research Laboratory, Washington, DC 20375, USA). AIP Conf. Proc.,
429(Shock Compression of Condensed Matter--1997), 809-812
(English) 1998 American Institute of Physics. CODEN: APCPCS.
ISSN: 0094-243X. DOCUMENT TYPE: Journal CA Section: 50
(Propellants and Explosives)
Time-resolved absorption measurements of ammonium perchlorate
(AP) decompn. under static high pressures are presented. Chem.
changes induced by pulsed laser heating (8 ms at 514 nm) are inferred
from the absorption spectra. Absorption measurements of the
decompn. process with 1 ms temporal resoln. were collected from 400
to 630 nm, during and up to 20 ms after the heating pulse. AP
decompn. as a function of initial pressure and laser fluence was
monitored to 2 GPa and to 11 J/cm2, resp. The role of pressure and
laser fluence in the fast decompn. of AP will be discussed. Global
reaction rates and possible reaction mechanisms will be addressed.
24. Secondary direct food additives permitted in food for human
consumption.
(Food Drug Administration, HHS, Washington, DC 20852, USA). Fed.
Regist., 63(138), 38746-38747, (English) 20 Jul 1998 Superintendent
of Documents. CODEN: FEREAC. ISSN: 0097-6326. DOCUMENT
TYPE: Journal CA Section: 17 (Food and Feed Chemistry)
The Food and Drug Administration (FDA) is amending the food
additive regulations to provide for the safe use of chlorine dioxide as an
antimicrobial agent in water used to wash certain fruits and vegetables
(an amt. not to exceed 3 ppm residual chlorine dioxide).
25. Photofragmentation of OClO(2A2 n1n2n3) * Cl(2PJ) + O2.
Delmdahl, R. F.; Ullrich, S.; Gericke, K.-H. (Institut fuer Physikalische
und Theoretische Chemie, Technische Universitaet Braunschweig,
Braunschweig D-38106, Germany). J. Phys. Chem. A, 102(39),
7680-7685 (English) 1998 American Chemical Society. CODEN:
JPCAFH. ISSN: 1089-5639. DOCUMENT TYPE: Journal CA Section:
74 (Radiation Chemistry, Photochemistry, and Photographic and Other
Reprographic Processes)
The photodissocn. dynamics of OClO(2A2 n1n2n3) * Cl(2PJ) + O2 is
investigated in the wavelength region between 360 and 450 nm.
Observation of nascent chlorine atom fragments produced in their
electronic ground state is performed by means of three-photon
excitation with subsequent recording of the vacuum UV laser-induced
fluorescence. Mode-specific branching ratios between the dominant
ClO(X2PW) + O(3PJ) and the minor Cl(2PJ) + O2 channel are obtained.
The obsd. quantum yield for Cl prodn. is detd. to be below 3.6% at
photolysis wavelengths between 365 and 450 nm depending on the
resp. vibrational level of OClO(2A2 n1n2n3). At dissocn. wavelengths
below 365 nm, a sharp rise in the chlorine formation is obsd. resulting
from a secondary photolysis step where vibrationally excited ClO(X2PW,
n * 4) radicals are dissocd.
26. Ultrafast measurements of chlorine dioxide photochemistry.
Ludowise, Peter Daniel (Univ. of California, Berkeley, CA, USA). 135
pp. Avail. UMI, Order No. DA9827021 From: Diss. Abstr. Int., B 1998,
59(3), 1127 (English) 1997. DOCUMENT TYPE: Dissertation CA
Section: 74 (Radiation Chemistry, Photochemistry, and Photographic
and Other Reprographic Processes)
Abstract Unavailable
27. Photoabsorption and near-threshold electron energy-loss spectroscopy
of OClO.
Marston, G.; Walker, I. C.; Mason, N. J.; Gingell, J. M.; Zhao, H.; Brown,
K. L.; Motte-Tollet, F.; Delwiche, J.; Siggel, M. R. F. (Department of
Chemistry, University of Reading, Reading RG6 2AD, UK). J. Phys. B:
At., Mol. Opt. Phys., 31(15), 3387-3405 (English) 1998 Institute of
Physics Publishing. CODEN: JPAPEH. ISSN: 0953-4075.
DOCUMENT TYPE: Journal CA Section: 73 (Optical, Electron, and
Mass Spectroscopy and Other Related Properties)
The spectroscopy of Cl dioxide, OClO, was studied using the
techniques of dissociative electron attachment (DEA), near-threshold
electron energy loss (EEL, 0-10 eV) and optical absorption (2.5-10.8
eV). Mass and energy analyses of the ions formed in the DEA
processes show that at energies e3 eV, the product ions are
predominantly near-thermal Cl-, suggesting that the accompanying O
atoms are excited electronically. All features obsd. in the EEL expts.
are in regions of optical absorption, indicating that the optically dark
doublet and quartet states have energies which overlap optically
allowed transitions. The optical spectrum itself is in good qual.
agreement with previous measurements, but there are differences in
relative absorption cross sections. Alternative interpretations of some
spectral features are proposed.
28. Production of aqueous chlorine dioxide solution for disinfecting raw
water and wastewater.
Rennerfelt, Lars (Swed. ). Eur. Pat. Appl. EP 864530 A2 16 Sep
1998,4 pp. DESIGNATED STATES: R: AT, BE, CH, DE, DK, ES, FR,
GB, GR, IT, LI, LU, NL, SE, MC, PT, IE, SI, LT, LV, FI, RO. (German).
(European Patent Organization). CODEN: EPXXDW. CLASS: ICM:
C01B011-02. ICS: C02F001-76. APPLICATION: EP 98-103130 23
Feb 1998. PRIORITY: DE 97-19710826 15 Mar 1997. DOCUMENT
TYPE: Patent CA Section: 49 (Industrial Inorganic Chemicals) Section
cross-reference(s): 60, 61
A procedure is provided for prodn. of an aq. ClO2 soln. contg. a Fe3+
hydrolysis product as a flocculation agent by using an alkali metal
chlorite or chlorate and a Fe3+ salt (e.g., FeCl3) as starting materials.
The procedure involves (1) prepn. of an aq. strongly acidic soln. of the
Fe3+ salt without causing Fe3+ hydrolysis, (2) addn. of the alkali metal
chlorite or chlorate, and (3) diln. of the mixt. with water to increase pH to
1-6 (preferably to 1-3). The resulting ClO2 soln. is suitable for
disinfection and purifn. of crude water and wastewater treatment.
29. Method and apparatus for monitoring and controlling characteristics of
process effluents.
Garver, Theodore M. Jr (Alberta Research Council, Can.). PCT Int.
Appl. WO 9840721 A1 17 Sep 1998, 37 pp. DESIGNATED STATES:
W: BR, CA, ID, NO; RW: AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE,
IT, LU, MC, NL, PT, SE. (English). (World Intellectual Property
Organization). CODEN: PIXXD2. CLASS: ICM: G01N021-33. ICS:
D21C009-10. APPLICATION: WO 98-CA243 10 Mar 1998.
PRIORITY: US 97-814519 10 Mar 1997. DOCUMENT TYPE: Patent
CA Section: 43 (Cellulose, Lignin, Paper, and Other Wood Products)
Section cross-reference(s): 60, 73
Methods for monitoring and controlling a characteristic of process
waters or effluent (esp. from wood pulp bleaching, pulping, and paper
making processes utilizing a bleaching agent such as H2O2, Na2S2O4,
ClO2, Cl2, or O3 or a pulp delignification process utilizing a
delignification agent such as NaOH, Na2S, O2, Na2SO3, and various
enzymes including ligninase, xylanase, mannanase, laccase, and
peroxidase) entails obtaining at least two measurements of (e.g., UV)
light absorption of the effluent, by taking a first measurement measured
at a first wavelength, and a second measurement measured at a
second wavelength, then detg. a ratio of the two measurements and
comparing the ratio to a predetd. interrelationship of the ratio and the
characteristic of the effluent, thereby detg. the actual value of the
characteristic. App. for monitoring a characteristic of an effluent of a
process is also described which comprises means for obtaining at
least two measurements of UV light absorption of the effluent, a first
measurement measured at the first wavelength, a second
measurement measured at a second wavelength and means for
comparing the ratio of the two measurements to a predetd.
interrelationship of the ratio and the characteristic of the effluent,
thereby detg. the actual value of the characteristic.
30. Viscosity changes in black liquor when bleach plant filtrates are added.
Ledung, Lars; Ulmgren, Per (Swedish Pulp and Paper Research
Institute (STFI), Stockholm, Swed.). Int. Chem. Recovery Conf., Volume
1, 157-167. TAPPI Press: Atlanta, Ga. (English) 1998. CODEN:
66PKAJ. DOCUMENT TYPE: Conference CA Section: 43 (Cellulose,
Lignin, Paper, and Other Wood Products)
The viscosity of black liquor affects evapn., pumping and droplet
formation, that are important for the firing in the recovery furnace. In this
paper, we present results from viscosity measurements on two different
softwood black liquors, and black liquors mixed with: D-(chlorine
dioxide), P-(peroxide) and Q-stage (chelating) bleach plant filtrates.
The viscosity was measured at three temps., 100癈, 115癈 and
130癈. The dry solids content was varied in the range of 50 to 75% by
wt. The viscosity of the black liquor was not significantly affected at a
given dry solids content by the addn. of P-stage filtrate but increased
2-3 times when Q-stage filtrate was added. The addn. of D-filtrate also
resulted in an increase in viscosity, but not to the same extent as the
Q-filtrate. The filtrates were added to the black liquor either by a quick
mixing by pouring the components together or by a dropwise and
controlled mixing. The difference in viscosity following these two
techniques was negligible. From chem. anal. and a multivariate data
evaluation, it was concluded that the increase in viscosity when bleach
plant filtrates were added was not a result of one single variable but
rather a series of compositional changes, such as a higher concn. of
inorg. ions, such as calcium and magnesium ions, which cause
flocculation of the lignin in black liquors, a lower residual alkali content
and a lower COD-value (COD).
31. Studies on the potential use of chlorine dioxide for treatment of seafood
products: microbiology, nutritional analysis, and mutagenicity.
Kim, Jeongmok (Univ. of Florida, Gainesville, FL, USA). 172 pp. Avail.
UMI, Order No. DA9824100 From: Diss. Abstr. Int., B 1998, 59(2), 473
(English) 1997. DOCUMENT TYPE: Dissertation CA Section: 17
(Food and Feed Chemistry)
Abstract Unavailable
32. Geminate recombination and vibrational relaxation dynamics of
aqueous chlorine dioxide: A time-resolved resonance Raman study.
Hayes, Sophia C.; Philpott, Matthew J.; Reid, Philip J. (Department of
Chemistry, University of Washington, Box 351700, Seattle, WA 98195,
USA). J. Chem. Phys., 109(7), 2596-2599 (English) 1998 American
Institute of Physics. CODEN: JCPSA6. ISSN: 0021-9606.
DOCUMENT TYPE: Journal CA Section: 74 (Radiation Chemistry,
Photochemistry, and Photographic and Other Reprographic
Processes)
The photochem. dynamics of aq. chlorine dioxide (OClO) are
investigated using time-resolved resonance Raman spectroscopy.
Stokes and anti-Stokes spectra are measured as a function of time
following photoexcitation of OClO using degenerate pump and probe
wavelengths at 390 nm. The temporal evolution of OClO Stokes
intensity is found to be consistent with the reformation of ground-state
OClO by subpicosecond geminate recombination of the primary ClO
and O photofragments. Anti-Stokes intensity is obsd. for transitions
corresponding to the sym. stretch of OClO demonstrating that upon
geminate recombination, excess vibrational energy is deposited along
this coordinate. Dissipation of this energy to the surrounding solvent
occurs with a time const. of ~9 ps. Finally, a delay in the appearance of
OClO anti-Stokes intensity relative to geminate recombination is obsd.
demonstrating that the excess vibrational energy available to OClO is
initially deposited along the resonance Raman inactive asym. stretch
coordinate with the exchange of energy between this coordinate and
the sym. stretch occurring with a time-const. of ~5 ps.
33. Can ozone and ozone oxidative byproducts be formed during the
electrolysis of salt brine?.
Gordon, Gilbert; Emmert, Gary; Gauw, Renee; Bubnis, Bernard (Miami
University Dep. Chemistry and Biochemistry, Oxford, OH 45056, USA).
Ozone: Sci. Eng., 20(3), 239-249 (English) 1998 Lewis Publishers.
CODEN: OZSEDS. ISSN: 0191-9512. DOCUMENT TYPE: Journal
CA Section: 61 (Water)
Salt brine electrolysis systems produce a soln. that can contain up to
400 mg/L free available chlorine (FAC). These systems are very
appealing to small utilities. The scientific literature contains numerous
reports from utilities using electrolysis systems citing enhanced
microbiol. kill rates and lower THM levels than normally would be
expected by disinfection with FAC alone. Researchers have
speculated that the presence of minority oxidant species (ozone and/or
chlorine dioxide) are responsible for the obsd. increased disinfection
capability of salt brine electrolysis systems. If strong oxidants such as
ozone and chlorine dioxide are present in electrolysis cell liquors, the
chem. reactions that can occur are complicated both
thermodynamically and kinetically. This paper describes anal. methods
developed to identify reactive species and potential interferences in
salt brine electrolysis cell anode liquors.
34. Comparison of spectrophotometric methods for measuring chlorine
dioxide in drinking water.
Hofmann, R.; Andrews, R. C.; Ye, Q. (Dep. Civiyl Engineering, Univ.
Toronto, Toronto, ON M5S 1A4, Can.). Environ. Technol., 19(8),
761-773 (English) 1998 Selper Ltd. CODEN: ENVTEV. ISSN:
0959-3330. DOCUMENT TYPE: Journal CA Section: 61 (Water)
Section cross-reference(s): 79
The recognition that chlorine disinfection of drinking water may not be
effective in controlling such as Cryptosporidium may lead to the greater
use of stronger alternative disinfectants, such as chlorine dioxide.
Typical chlorine dioxide residual concn. requirements for disinfection
may extend to less than 0.1 mg L-1, thus requiring very good
quantitation methods for optimal process control. Traditional methods
have been cumbersome and sometimes inaccurate. This study examd.
three spectrophotometric methods for measuring chlorine dioxide in the
<0.1 mg L-1 to 2 mg L-1 range, using acid chrome violet K (ACVK),
lissamine green B, and amaranth reagents. Each methods was
assessed using both lab. reagent water and various natural waters to
identify the resp. linear range, method precision, and the possible
interference from natural color due to aq. org. matter. Interferences
arising from the presence of chlorine, chloramines, chlorite, chlorate,
and permanganate were also evaluated, along with potential need to
correct for temp. changes.
35. Management & design of process exhaust systems in an I/C
manufacturing environment for emission minimization.
Mattrey, Joseph F.; Miller, John D. (Advanced Technology Division,
Black & Veatch, USA). Proc. - Inst. Environ. Sci. Technol.,
44th(Contamination Control), 497-504 (English) 1998 Institute of
Environmental Sciences and Technology. CODEN: PESTF7.
DOCUMENT TYPE: Journal CA Section: 59 (Air Pollution and Industrial
Hygiene) Section cross-reference(s): 48, 76
Process exhaust management from integrated circuit manufg. is
discussed. A guide for facilities engineers or process exhaust system
designers to understand process exhaust systems and to achieve
emissions minimization at optimum cost is provided. Emission
sources, quantities emitted, and characteristics of all exhausts are
reviewed. Process exhaust treatment philosophy, including of
point-of-use treatment devices, segregation of exhaust streams, and
end-of-duct abatement systems are discussed to facilitate system
selection and design.
36. Pulp and paper industry: preparing for the accidental release
prevention program.
Bhatt, Tapan; Dorris, Scott (Trinity Consultants, Inc., Baton rouge, LA,
USA). Proc., Annu. Meet. - Air Waste Manage. Assoc., 89th,
ra11602/1-ra11602/10 (English) 1996 Air & Waste Management
Association. CODEN: PAMEE5. ISSN: 1052-6102. DOCUMENT
TYPE: Journal; (computer optical disk) CA Section: 59 (Air Pollution
and Industrial Hygiene) Section cross-reference(s): 43
Provisions of the Accidental Release Prevention Program (Section
112(r)) apply to facilities that produce, process, handle, or store
regulated substances in excess of threshold amts. A significant no. of
pulp and paper mills generate or process a no. of chems. on the
Section 112(r) list in excess of threshold amts. Accordingly, these mills
would be required to demonstrate compliance with Section 112(r)
requirements. These regulations will impose a significant operational
and cost burden on the affected mills. Thus, mills will have to resort to
develop strategies to prep. for the regulatory requirements of Section
112(r) in a cost- effective manner. These strategies include substituting
regulated chems. for non-regulated ones and using optimum resources
to develop a comprehensive risk management plan. This paper
provides an overview of the most recent regulatory developments of
Section 112(r) as they apply to the pulp and paper industry. It also
discusses some strategies which can be implemented by pulp and
paper mills to demonstrate compliance with requirements of Section
112(r) effectively and efficiently.
37. Acid and halogen gas monitoring utilizing ion mobility spectroscopy
(IMS).
Bacon, Tad; Webber, Kurt (Environmental Technologies Group,
Baltimore, MD, USA). Proc., Annu. Meet. - Air Waste Manage. Assoc.,
89th, ta3002/1-ta3002/12 (English) 1996 Air & Waste Management
Association. CODEN: PAMEE5. ISSN: 1052-6102. DOCUMENT
TYPE: Journal; (computer optical disk) CA Section: 59 (Air Pollution
and Industrial Hygiene) Section cross-reference(s): 79
Many of the acid and halogen gases are difficult to monitor using
traditional techniques. This paper describes the use of ion mobility
spectroscopy to monitor gases such as HF, HCl, Cl2, Cl02, HCN and
others with limits of detection down to 1 ppb. Monitoring experience for
stacks and ambient air applications is presented. Theory of operation,
hardware, and actual field results are given. Future applications of the
technique are discussed, and the possibility of a "total acid gas
monitor" is demonstrated.
38. Reactions of lignin model compounds with chlorine dioxide. Molecular
orbital calculations.
Elder, Thomas (School Forestry, Auburn University, Auburn, AL 36849,
USA). Holzforschung, 52(4), 371-384 (English) 1998 Walter de Gruyter
& Co. CODEN: HOLZAZ. ISSN: 0018-3830. DOCUMENT TYPE:
Journal CA Section: 43 (Cellulose, Lignin, Paper, and Other Wood
Products) Section cross-reference(s): 22, 69
Based on previously proposed chem. mechanisms accounting for the
formation of various oxidn. products from both phenolic and
non-phenolic lignin model compds., semi-empirical MO calcns. were
completed. The computational results indicate that the heats of
reaction for the phenolic model compd. are consistently lower than
those for the etherified model. These data are in agreement with the
exptl. results which indicate that when both types of model compds. are
present, the phenolic compds. are preferentially oxidized.
39. Reactions of PAH with chlorine and chlorine dioxide in coal tar-lined
pipes.
Merkel, Till; Maier, Matthias; Sacher, Frank; Maier, Dietrich
(Engler-Bunte-Institut, Universitaet Karlsruhe, Karlsruhe D-76128,
Germany). Acta Hydrochim. Hydrobiol., 26(5), 279-287 (English) 1998
Wiley-VCH Verlag GmbH. CODEN: AHCBAU. ISSN: 0323-4320.
DOCUMENT TYPE: Journal CA Section: 61 (Water) Section
cross-reference(s): 25
In presence of disinfectants, PAHs can be remobilized from the coal tar
lining of water distribution mains. Reactions of the PAH with Cl2 and
ClO2 can lead to chlorinated PAH that might show higher mutagenic
effects than the parent PAH. Solid-phase microextn. as a sampling
method in combination with a GC-MS was used to achieve detection
limits in the lower nanogram-per-liter level for PAH and chlorinated
PAH. Thus, the reactions of 4 PAH (anthracene, fluoranthene, fluorene,
and phenanthrene) with Cl2 and ClO2 under conditions prevalent in
drinking water distribution systems could be investigated. In batch
expts. with demineralized and drinking water at pH 7, the concns. of
fluoranthene, fluorene, and phenanthrene remained const., whereas
anthracene reacted quant. with both disinfectants. In these reactions,
no chlorinated products could be detected, only
mono-hydroxyanthracene and anthraquinone were formed. A reaction
mechanism for both reaction products is proposed. The results
suggest that oxidn. is the major pathway of the reaction of PAH with
disinfectants in the systems under investigation.
40. Peroxide bleaching of chemical pulp in the presence of delignification
catalysts.
Fukushima, Takamasa; Oki, Takahiro; Koshitsuka, Tetsuo; Shitamura,
Tadashi (Mitsubishi Gas Chemical Co., Ltd., Japan). Jpn. Kokai
Tokkyo Koho JP 10219575 A2 18 Aug 1998 Heisei, 10 pp.
(Japanese). (Japan). CODEN: JKXXAF. CLASS: ICM: D21C009-10.
ICS: D21C009-14; D21C009-16. APPLICATION: JP 97-23904 6 Feb
1997. DOCUMENT TYPE: Patent CA Section: 43 (Cellulose, Lignin,
Paper, and Other Wood Products)
The catalysts are oxy acids of groups IV-VI elements or their salts and
the bleaching proceeds to a stage of ClO2 bleaching without the needs
of intermediate washing. The bleaching can be carried out in the
presence of a chelating agent.
41. Method, composition and system for the controlled release of chlorine
dioxide gas.
Speronello, Barry K.; Thangaraj, Appadurai; Yang, Xiaolin (Engelhard
Corporation, USA). PCT Int. Appl. WO 9838865 A1 11 Sep 1998, 39
pp. DESIGNATED STATES: W: AL, AM, AT, AU, AZ, BA, BB, BG,
BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, GM,
GW, HU, ID, IL, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU,
LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG,
SI, SK, SL, TJ, TM, TR, TT, UA, UG, UZ, VN, YU, ZW, AM, AZ, BY, KG,
KZ, MD, RU, TJ, TM; RW: AT, BE, BF, BJ, CF, CG, CH, CI, CM, DE,
DK, ES, FI, FR, GA, GB, GR, IE, IT, LU, MC, ML, MR, NE, NL, PT, SE,
SN, TD, TG. (English). (World Intellectual Property Organization).
CODEN: PIXXD2. CLASS: ICM: A01N059-00. ICS: A23L003-358;
C02F001-50; C01B011-02; A61L002-20; B01D053-38.
APPLICATION: WO 98-US3950 27 Feb 1998. PRIORITY: US
97-808768 3 Mar 1997; US 97-891665 11 Jul 1997; US 97-961488 30
Oct 1997. DOCUMENT TYPE: Patent CA Section: 5 (Agrochemical
Bioregulators) Section cross-reference(s): 17, 63
Chlorine dioxide gas is generated in a controlled release manner by
combining at least one metal chlorite, such as Na chlorite, and a dry
solid hydrophilic material that reacts with the metal chlorite in the
presence of water vapor, but does not react with the metal chlorite in
the absence of liq. water or water vapor, to produce chlorine dioxide
gas in a sustained amt. of from 0.001 to 1,000 ppm. The dry solid
hydrophilic material is zeolite, hydrous or calcined clay, etc. The
chlorine dioxide gas is a deodorant and disinfectant, esp. for the food
industry.
42. Study on treatment of lightly polluted groundwater.
Sun, Ji; Liu, Guohong (Harbin Architectural University, Peop. Rep.
China). Zhongguo Jishui Paishui, 14(1), 50, 53 (Chinese) 1998
Zhongguo Jishui Paishui Bianjibu. CODEN: ZGPAFP. ISSN:
1000-4602. DOCUMENT TYPE: Journal CA Section: 61 (Water)
The characteristics of O3-biol. activated C technol. was introduced, and
a O3 contact-activated C filtration- mineralization-ClO2 sterilization
process for treating lightly polluted groundwater was proposed. The
design parameters were given. It showed that the COD was
decreased from 2 to 0.25 mg L-, and 1-methyl-3-isopropyl-benzene,
and phenetole were removed by 100%; whereas hardness was
increased by 150% and pH decreased 8%.
43. Comparison of mutagenicity of drinking water disinfected with chlorine
dioxide and liquid chlorine.
Huang, Junli; Li, Haibo; Mao, Ning; Li, Baixiang; Wu, Kun (Harbin Univ.
Architecture & Engineering, Harbin 150008, Peop. Rep. China).
Huanjing Huaxue, 17(4), 381-387 (Chinese) 1998 Kexue Chubanshe.
CODEN: HUHUDB. ISSN: 0254-6108. DOCUMENT TYPE: Journal
CA Section: 61 (Water) Section cross-reference(s): 4
Comparative test on mutagenicity of water samples disinfected with
ClO2 and liq. Cl was carried out using Ames test. The results showed
that the mutagenicity of water disinfected with ClO2 was not affected, in
contrast, water samples disinfected with liq. Cl showed mutagenicity.
44. Method for manufacture of chlorine dioxide.
Tenney, Joel (Akzo Nobel N.V.; Eka Chemicals AB, Neth.). Eur. Pat.
Appl. EP 866031 A1 23 Sep 1998, 7 pp. DESIGNATED STATES: R:
AT, BE, CH, DE, DK, ES, FR, GB, GR, IT, LI, LU, NL, SE, MC, PT, IE,
SI, LT, LV, FI, RO. (English). (European Patent Organization).
CODEN: EPXXDW. CLASS: ICM: C01B011-02. APPLICATION: EP
98-200588 25 Feb 1998. PRIORITY: US 97-821164 20 Mar 1997.
DOCUMENT TYPE: Patent CA Section: 49 (Industrial Inorganic
Chemicals)
A process is described for manuf. of chlorine dioxide by the redn. of
chlorate ions with hydrogen peroxide as a reducing agent in a tubular
reactor, preferably in the presence of a mineral acid, wherein the
preferable degree of chlorate conversion to chlorine dioxide in the
reactor is ~>75%, preferably ~80 to 100%.
45. Agent for deodorization, disinfection and antisepsis of indoor air.
Narita, Yoshiharu (MY Corporation Y. K., Japan). Jpn. Kokai Tokkyo
Koho JP 10211265 A2 11 Aug 1998 Heisei, 6 pp. (Japanese).
(Japan). CODEN: JKXXAF. CLASS: ICM: A61L009-04.
APPLICATION: JP 97-15431 29 Jan 1997. DOCUMENT TYPE:
Patent CA Section: 59 (Air Pollution and Industrial Hygiene)
The agent comprises aq. soln. of sodium hypochlorite (0.001-18%)
contg. 1-5000 ppm chlorine dioxide with pH 10-12, and stabilizing
agent for ClO2 (e.g., ester of acrylic acid).
46. Bactericidal activity of chlorine dioxide against Escherichia coli in
water and on hard surfaces.
Foschino, Roberto; Nervegna, Ilaria; Motta, Antonella; Galli, Antonietta
(Dipartimento di Scienze e Tecnologie Alimentari e Microbiologiche,
Universita degli Studi di Milano, Milan 20133, Italy). J. Food Prot.,
61(6), 668-672 (English) 1998 International Association of Milk, Food
and Environmental Sanitarians. CODEN: JFPRDR. ISSN:
0362-028X. DOCUMENT TYPE: Journal CA Section: 10 (Microbial,
Algal, and Fungal Biochemistry)
The efficacy of chlorine dioxide as a disinfectant was evaluated against
cells of Escherichia coli ATCC 11229 in aq. suspension and adhering
to the surfaces of stainless steel AISI 304 and PVC. The concns.
tested ranged from 0.7 to 14 mg/L; the exposure times investigated
were 30 s and 1, 2, 4, and 8 min. When the bacteria were suspended
in water with 1.4 mg/L of chlorine dioxide, a 105-fold redn. of the initial
viable count occurred within 30 s; when cells were attached to the steel
surface, the same rate of inactivation took place only after 6 min with 7
mg/L or 4 min with 14 mg/L of chlorine dioxide. A 5-log redn. was not
obtained when organisms were adhered to polyvinyl chloride (PVC).
Scanning electron microscope micrographs of contaminated surfaces
revealed that the PVC was very rough with pores much larger in diam.
than the cells. Time values detg. a 90% redn. of the E. coli population
(90% killing time) were calcd. for each concn. of disinfectant tested in
suspension and on the steel surface. If the same exptl. conditions were
strictly adopted, linear functions of the log of bacterial inactivation could
be plotted (log 90% killing time vs. log concn. of disinfectant). This
work showed that results obtained with suspension tests could not be
used to est. disinfection of hard surfaces.
47. Use of EC criteria for determining health and environmental hazards for
classification of chemicals for environmental risk.
Winder, Chris; Gonzalez-Calderon, Didier (Department of Safety
Science, University of New South Wales, Sydney 2052, Australia).
Regul. Toxicol. Pharmacol., 27(1, Pt. 1), 38-46 (English) 1998
Academic Press. CODEN: RTOPDW. ISSN: 0273-2300.
DOCUMENT TYPE: Journal CA Section: 4 (Toxicology)
European Community risk phrases were used to classify chems. in
terms of environmental hazard. (c) 1998 Academic Press.
48. Spectroscopic characterization of supersonic molecular beams.
Vaida, Veronica; Frost, Gregory J.; Goss, Lisa M. (Dep. of Chem. and
Biochem., Univ. of Colorado, Boulder, CO 80309-0215, USA). Isr. J.
Chem., 37(4), 387-393 (English) 1997 Laser Pages Publishing.
CODEN: ISJCAT. ISSN: 0021-2148. DOCUMENT TYPE: Journal CA
Section: 73 (Optical, Electron, and Mass Spectroscopy and Other
Related Properties)
A general spectroscopic method is described by which samples prepd.
in supersonic mol. beams can be characterized independently in their
ground and excited electronic states. The centerpiece of this expt. is a
Fourier transform spectrometer operating at high resoln. in the IR,
visible, and UV. This method is illustrated with studies of the NO2 and
OClO radicals prepd. in supersonic mol. beams at temps. and
pressures characteristic of the Earth's atm. This general spectroscopic
method is discussed by analogy with low- and high-resoln. studies of
electronic states which in limited cases were used to characterize
sample conditions in supersonic mol. beam expts.
49. Mechanism of Chlorine Dioxide and Chlorate Ion Formation from the
Reaction of Hypobromous Acid and Chlorite Ion.
Furman, Christopher S.; Margerum, Dale W. (Department of Chemistry,
Purdue University, West Lafayette, IN 47907-1393, USA). Inorg.
Chem., 37(17), 4321-4327 (English) 1998 American Chemical
Society. CODEN: INOCAJ. ISSN: 0020-1669. DOCUMENT TYPE:
Journal CA Section: 67 (Catalysis, Reaction Kinetics, and Inorganic
Reaction Mechanisms)
The rate of oxidn. of ClO2- by HOBr is first-order in each reactant and is
general-acid-assisted in the presence of phosphate or carbonate
buffers. The products are ClO2 and ClO3-, where the relative yield
depends on the concn. ratio of ClO2-/OH-. The kinetic dependence
indicates the presence of a steady-state intermediate, HOBrOClO- (or
HOBrClO2-), that undergoes general-acid-assisted reactions to
generate a metastable intermediate, BrOClO (or BrClO2). This
intermediate reacts very rapidly by two competing pathways: in one
path ClO2- reacts to form 2ClO2 and Br-, and in the other path OH- (or
H2O) reacts to form ClO3- and Br-. Competition between these
pathways dets. the yield of ClO2 but does not affect the rate of loss of
HOBr. The reactions are followed by the formation of ClO2 in the
presence of excess ClO2-. The rate expression for the loss of HOBr is
k1[ClO2-][HOBr]*(kHA[HA])/(k-1 + *(kHA[HA])), where k1 (for the
formation of the intermediate) is 97 M-1 s-1 and kHA/k-1 (M-1) values,
which depend on the acid (HA) strength, are 3.1 * 105 for H3O+, 8.3 for
H2PO4-, and 0.064 for HCO3- (25.0 癈, m = 1.0 M). Reactions between
HOBr and ClO2- are much faster than those between HOCl and ClO2-.
50. Mutagenicity of extracts of lake drinking water treated with different
disinfectants in bacterial and plant tests.
Monarca, Silvano; Zanardini, Alberto; Feretti, Donatella; Dalmiglio,
Antonio; Falistocco, Egizia; Manica, Patrizia; Nardi, Giuseppe (Dep. of
Experimental and Applied Medicine, Hygeiene Section, University of
Brescia, Brescia I-25123, Italy). Water Res., 32(9), 2689-2695
(English) 1998 Elsevier Science Ltd. CODEN: WATRAG. ISSN:
0043-1354. DOCUMENT TYPE: Journal CA Section: 61 (Water)
Section cross-reference(s): 4
Raw water and drinking water samples collected from 5 treatment
plants supplied by a northern Italian lake in two periods of the year
(summer and winter) were studied for their mutagenicity. The water
samples were concd. on silica C18 cartridges, and the adsorbates were
tested at increasing doses with a bacterial short-term mutagenicity test
(Ames test with Salmonella typhimurium TA98 and TA100 strains),
which reveals the gene-mutation-inducing ability of pollutants, and with
a plant genotoxicity bioassay (Tradescantia/micronucleus test), which
dets. clastogenicity (chromosome-breaking ability). Raw water
samples from all treatment plants were found to contain bacterial
direct-acting mutagens detectable mainly with the TA98 strain. The
analyses of drinking water samples after water treatment showed some
interesting results: TA98 mutagenicity was reduced when ozone was
used together with chlorine dioxide, but TA100 mutagenicity was
increased, although only in the summer sample; mutagenicity
detectable with both strains was always reduced after chlorine dioxide
disinfection; on the contrary, in all treatment plants using NaClO, TA98
mutagenicity of winter samples increased. Raw lake water induced a
high no. of micronuclei in the Tradescantia/micronucleus test, showing
a strong clastogenicity. This activity was higher in the NaClO-treated
samples, and lower with the other disinfectants. Therefore, disinfection
of lake water with ozone and(or) chlorine dioxide seems to be a
suitable alternative to the use of NaClO for controlling the formation of
nonvolatile mutagens. The concn. method coupled with the two
mutagenicity tests was found to be a simple, rapid, and relatively
inexpensive system for monitoring treatment plants and studying the
influence of different disinfectant systems on water mutagenicity.