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The transition from purchasing liquid chlorine to sodium hypochlorite production has been considered. The advantages and disadvantages of different disinfectants that can be used in the disinfection stage of drinking water have been demonstrated. The focused attention on the drawbacks of using liquid chlorine includes risks during dosing, transportation, storage, and the formation of chlorinated organic compounds, predominantly trichloromethanes, particularly chloroform, which exhibit significant mutagenic effects and a carcinogenic risk. The materials of the Smolinsky water supply and sewerage system of the regional communal water supply and sewerage enterprise "Dnipro-Kirovohrad" regarding the technology of disinfecting natural water and the quality of drinking water have been analyzed. The expediency of using a purchased sodium hypochlorite solution in the disinfection stage of drinking water has been determined. It has been shown through examples that some problems associated with the use of purchased sodium hypochlorite solution can be solved by launching its own production. Changes to the current technological scheme have been proposed with the aim of reducing chlorine by-products and improving the organoleptic properties of drinking water. [ABSTRACT FROM AUTHOR]

The sterilizing effect of heterotrophic bacteria, sulfur bacteria and iron bacteria treated with chlorine dioxide is examined experimentally in this paper. The weight loss method was used to simultaneously study the comparative corrosion behavior of four different metals under treatments of chlorine dioxide, liquid chlorine and their mixture. The experimental results indicated that chlorine dioxide had a good sterilization effect against heterotrophic, sulfur and iron bacteria at different dosages, pH, temperatures and reaction conditions. Chlorine dioxide is used as a high-efficiency circulating water oxidizing sterilizer; its sterilizing effect on heterotrophic, sulfur and iron bacteria exceeds 90% at 0.6 mg/L dosage, pH 7, 20°C and 15 min reaction. Considering its strong oxidizing effect and chemical corrosion of metal pipes, the corrosion behavior of ClO2, liquid chlorine and their mixture to carbon steel, aluminum, red copper and stainless steel were investigated. It was concluded that ClO2, liquid chlorine and their mixture could all cause metal corrosion: liquid chlorine caused the greatest metal corrosion and ClO2 gave the weakest metal corrosion; moreover, corrosion inhibition was observed under low concentrations of ClO2. Therefore, the corrosion behavior of ClO2 needs to be considered when it used as a sterilant for circulating cooling water. [ABSTRACT FROM AUTHOR]

Urban atmospheric transport and dispersion are investigated through the simulation of hypothetical contaminant releases. The Weather Research and Forecasting (WRF) model is used to simulate a New York City heat event from 18-20 July 2013 using three different urban parametrizations and the Noah land-surface model, with simulation results reflecting the variations in the parametrization of urban drag and building-wake effects, leading to simulated ranges of 2 °C for the surface air temperature, 3 m s−1 for the surface wind speed, and 20° for the surface wind direction. The Quick Urban and Industrial Complex (QUIC) model for atmospheric transport and dispersion is used to simulate three hypothetical contaminant releases in Central Park in New York City: the release of a biological agent from a backpack sprayer, the release of pressurized liquid chlorine from a rupture in a tanker truck, and the release of a radioisotope from a radiological dispersion device. The WRF model results from the four simulations at the times of maximum and minimum surface air temperature are used to initialize the QUIC model, with the different urban parametrizations leading to differences in plume directions and contaminant contour areas of up to 33° and up to a factor of 2.1, respectively. The variation in the size of predicted contours at the toxicity threshold may influence emergency-response decisions, while the differences in the predicted plume direction may influence where emergency-response personnel are directed. The results support the development and deployment of the best urban parametrization scheme in a forecast model for predicting hazard areas. [ABSTRACT FROM AUTHOR]

In paper I of this series, a molecular dynamics (MD) study of liquid chlorine was performed, and it includes the definition and observation of operational cage variables. These cage variables were used to describe the local environment of a rotating axially symmetric molecule, or probe. Probe and cage properties of interest, such as rotational correlation functions and momentum correlation functions, were computed, together with an effective distribution of librational cage frequencies. In the second part of this work, we develop a stochastic model which includes the relevant elementary relaxation processes previously identified by the MD study. This stochastic model is based upon a multi-dimensional Fokker–Planck equation for the coupled dynamics of the probe and cage orientations, the angular momentum of the probe, and the librational frequencies for the probe in the cage. Semi-analytical approximations, based upon a ‘‘Born–Oppenheimer’’-type separability of fast and slow variables, are used in order to calculate probe and cage correlation functions, and they are found to be in reasonable agreement with the MD results. In an appendix the Born–Oppenheimer approximation for stochastic operators is developed. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The first salt‐like compounds of dications with [AuCl4]– anions are reported. The compounds Zn[AuCl4]2·(AuCl3)1.115 (1) and Cd[AuCl4]2 (2) are obtained from reactions of MCl2 (M = Zn, Cd) and elemental gold in liquid chlorine at ambient temperature under autogenous pressure and subsequent annealing at 230 °C. The structure of 1 represents an incommensurately modulated composite [superspace group C2/c(α0γ)0s] built of two subsystems. The first subsystem contains chains of zinc(II) tetrachloridoaurate(III), which feature a slightly distorted octahedral coordination of Zn and can be described by the Niggli formula 1∞{Zn[AuCl4]1/1[AuCl4]2/2}. The second subsystem consists of Au2Cl6 molecules, which are located in channels built up by the first subsystem. The structural parameters of the hosted Au2Cl6 molecules show only small deviations from neat AuCl3. The crystal structure of Cd[AuCl4]2 (2) consists of chains built of Cd2+ ions coordinated by bridging [AuCl4]– anions and alternating Cd‐Au sequence. Cd has a distorted octahedral coordination environment. [ABSTRACT FROM AUTHOR]

Introduction. Effectiveness and applicability of chlorine-containing disinfectants used in the practice of water treatment were studied for the purpose of solving urgent environmental problems associated with the formation of secondary pollutants generated during the chlorination of natural water. Such contaminations are mostly represented by organohalogen compounds producing strong negative effect on the physiological state of living organisms, including human beings. To solve this problem, it is proposed to use technical grade sodium hypochlorite instead of traditional liquid chlorine when selecting disinfectants for natural water. Technical grade sodium hypochlorite is obtained by saturating solutions of diaphragmatic sodium hydroxide with chlorine gas at the stage of liquefaction of chlorine and caustic soda production. Sodium hypochlorite solution is significantly less toxic, non-flammable and not explosive. Materials and methods. A comparative study was conducted as to changes in the content of organohalogen compounds and heavy metals in water treated with sodium hypochlorite and liquid chlorine of one year duration. Analyses of water samples of water treated with liquid chlorine and sodium hypochlorite were made to measure concentrations of heavy metals, organohalogen compounds and other drinking water quality indicators, as specified by current regulations. Results. The obtained data demonstrate that the use of sodium hypochlorite for disinfection provides a higher quality of drinking water, therefore, it is advisable to replace liquid chlorine with technical grade sodium hypochlorite in the process of water treatment as potable water. Conclusions. The results of the study formed the basis for numerous industrial tests and subsequent implementation in existing water treatment plants in many large cities of Russia.

We present a novel process for drying chlorine by formation of a clathrate hydrate. Liquid chlorine is dried in a rotor-stator spinning disc (RSSD) heat exchanger, which has heat transfer coefficients up to 10 kW/m 2 /K, independent of the flow rate. Benefits of this novel drying process are (1) compactness of the spinning disc heat exchanger, minimizing material investments, (2) blocking of the equipment by the adhesive hydrates is prevented by the rotation, and (3) no chlorine contamination by drying agents, e.g., sulfuric acid or zeolite. Batch and RSSD experiments were performed with dichloromethane as a model compound for liquid chlorine. Lower crystallization temperatures result in shorter induction times of the hydrate formation and thus faster water removal rates. Higher mass transfer rates at higher rotation speeds have the same effect. The results show that the RSSD heat exchanger facilitates an elegant, energy-efficient water removal process that can be applied to removal of trace amounts of water from hydrate forming liquids. [ABSTRACT FROM AUTHOR]

The physicochemical properties of electro activated water (EAW) are highly affected by process conditions. In this context, the effects of parameters such as brine concentration, electrolysis time and current for EAW generation have been investigated using Response Surface Methodology (RSM). The predictive model for each response had high accuracy relative to R2 values, namely, 0.85 for the oxidation reduction potential (ORP) and 0.94 for the free chlorine concentration (FCC). According to results, the brine concentration was the most significant factor that affected EAW character. Moreover, electrolysis time and brine concentration have synergetic effect on FCC. The mechanism of the EAW production was evaluated through the cyclic voltammogram (CV) of different brine concentrations on the graphite electrode. With the concentration increased anodic and cathodic peaks could be observed notably. Possible reaction pathways were evaluated on the cathode and anode sides. The formation of Cl2, O2, H2, Cl-, OH-, H+ were determined by CV measurements. [ABSTRACT FROM AUTHOR]

In order to quickly estimate the toxic gas concentration distribution of liquid chlorine in moving tank car after leakage and predict possible outcome (scope and degree of the influence) of hazardous gas, the characteristics of liquid chlorine leakage in moving tank was analyzed in this paper, and then dynamic changing leaking speed, the tanker's moving direction and velocity were introduced according to the defects of Gaussian model, and finally the model of toxic gas diffusion after liquid chlorine leakage in moving tank car was build. The new model was simulated and analyzed by MATLAB. The simulation results showed that: this model can rapidly and effectively calculate toxic gas concentration distribution in different places and different time after leakage of liquid chlorine in moving tanker, and it can also simulate the dynamic transformation process of the toxic gas and provide technical support and theoretical basis for the prediction and assessment at the scene of the toxic gas leakage accident. [ABSTRACT FROM AUTHOR]

Introduction. The purpose of research - to develop evidencebased requirements to technological water for tea drinks prepare. Methods and Materials. Large leaf black and green tea production of Sri Lanka. Model solutions. Determined of the total content of polyphenolic substances in tea drinks was measured with the method of Folin-Chokalteo. Determination of other indexes was determined with standard methods. Results and discussion. With concentration of total hardness equal to 7 mmol/dm³ occurred a decrease of polyphenolic substances content on 179 mg/dm³ (from 439 to 260 mg/dm³) in a black tea drink, and on 184 mg/dm³ (from 816 to 632 mg/dm³) polyphenol substances in the green tea drink. Presence of salt of hardness in the water adversely affected the color, taste and aroma of the tea drinks. Best taste has tea drink prepared on water with a value of TDS at 200 mg/dm³. The value of indicator of permanganate oxidation more than 1 mgO2/dm³, the organoleptic characteristics of the tea drinks, especially taste, are deteriorates. At a concentration of residual free chlorine at 0,2 mg/dm³ the taste lost expressive sequences, and smell of tea, especially green, became a barely perceptible. When residual free chlorine concentration is over 0,4 mg/dm³ for green tea drink and over 0,5 mg/dm³ for black tea drink it is begin to feel the smell of chlorine, causing a desire to abandon the consumption of drinks. The content of residual free chlorine in the water cause a reduction of content of polyphenolic substances, vitamin C and caffeine in drinks. If the concentration of residual free chlorine is 0,5 mg/dm³, the content of polyphenolic substances are reduced 11 % in black tea drinks, and 8,5 % in green tea drinks. For preparation of tea drinks with good organoleptic properties and minimal loss of nutrients we recomed to use water with content of free residual chlorine of 0,1 mg/ddm³, copper - 1 mg/ddm³, total iron - 0,2 mg/ddm³, hardness - 2 mmol/ddm³, permanganate oxidation value - 2 mgO2/ddm³, TDS - 100-250 mg/ddm³. Preparation of a tea drinks with further purified tap water which conforms to requirements allow to reduce the loss of polyphenolic substances in 1,5 times, vitamin C in 2,5 times, caffeine in 10% and significantly improved organoleptic characteristics in comparison with the drinks prepared on tap water without further purification. Conclusions. It is recommended for establishments of restaurant industry orientate on formulated requirements to water for tea drinks. [ABSTRACT FROM AUTHOR]

The ballistic resistance and self-sealing behavior of polyhedral oligomeric silsesquioxane (POSS)-enhanced polyurea (PU) coated TC-128 steel plates subjected to high speed impact were investigated experimentally and numerically. Both experimental and numerical results showed that the POSS-enhanced PU exhibited strong self-sealing properties under high-speed impact and could dramatically reduce leaking of toxic liquid from a hole in the railcar tank. Experimental results and simulation results agreed well for the ballistic limit of POSS-enhanced PU coated and uncoated TC-128 steel plates, with an average error of 5.72%. In terms of the size of hole left after the impact test, although the simulation result for the uncoated TC-128 steel plate was almost identical to the experimental result, the simulation result for the POSS-enhanced PU coating layer was doubled compared to the experimental result, probably due to the mass erosion effect. The POSS-enhanced PU material may serve as a class of effective protective coating layers to reduce the leaking of toxic chemicals from steel railcar tanks. [ABSTRACT FROM AUTHOR]

Nitrogen trichloride (NCl3) is a by-product of electrolytic chlorine manufacture, produced when the brine is contaminated with ammonia. A common treatment method is a thermal destruction process in which the NCl3 is absorbed in a solvent (CHCl3) using a distillation column with no liquid bottoms product. The chlorine gas is cooled through direct contact with liquid chlorine, which flashes and condenses the solvent and NCl3 vapours. The condensate drains through trays to a reboiler in which the NCl3 decomposes while the chlorine, solvent, NCl3 solution boils. This process is well-known and widely practiced but is known to experience catastrophic detonations. A vapour phase thermal decomposition of NCl3 does occur, particularly when the heat added through compression is considered. The known data on this decomposition reaction have been collected and converted in a rate expression that allows for integration within an ASPENPLUS process model. Different options for the compressor, precooler, intercooler and liquefier operations are considered, and their impact on the compressor and liquefier duties is reported. A different approach to the design and operation for a chlorine compression/liquefaction train is presented and discussed. © 2013 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

The use of acid electrolysed water (AcEW) is a relatively new sanitizing technique for brewery equipment. Experiments showed that a 30% AcEW (a free chlorine concentration of above 17 mg/L) was a sufficient and effective alternative to conventional sanitizers such as peracetic acid (2%). On the basis of the results of industrial-scale clean-in-place tests, an effective AcEW-based clean-in-place procedure, which requires only 10 min of cleaning and does not require final water rinsing after sanitation, was established for the bright beer tank. Copyright © 2013 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Abstract: This work presents the results of a study of the Tm3+/Tm2+ couple redox potentials vs. Cl–/Cl2 reference electrode at the temperature range (833 to 1073)K in molten equimolar NaCl–KCl and NaCl–2CsCl eutectic by direct potentiometric method. Initial concentrations of TmCl3 in solvents did not exceed 5.0mol%. Apparent standard redox potentials of the couples were determined in different solvents. Basic thermodynamic properties of the reaction were calculated. The dependence between the apparent standard redox potentials of the couples and the ionic potential of the solvents was established. [Copyright &y& Elsevier]

Abstract: The Jack Rabbit (JR) field experiment, involving releases of one or two tons of pressurized liquefied chlorine and ammonia into a depression, took place in 2010 at Dugway Proving Ground, Utah, USA. The releases, of duration about 30s from a short pipe at a height of 2m, were directed towards the ground. The dense two phase cloud was initially confined in a depression of 2m depth and 50m diameter. With wind speedsabout 1.5ms−1, the initial cloud was not well-confined in the depression and moved downwind. Formulas suggested by Briggs et al. in 1990 in this journal satisfactorily predict the time durations of confinement. Sensitivity runs with the SLAB dense gas model show that the effect of a long confinement on maximum downwind concentrations is strongest near the depression. The model-predicted and observed maximum 20s chlorine concentrations agree within a factor of two most of the time, as long as the release times based on Briggs’ theory are used. [Copyright &y& Elsevier]

Rossi-Fedele G, Guastalli AR, Doğramacı EJ, Steier L, De Figueiredo JAP. Influence of pH changes on chlorine-containing endodontic irrigating solutions. International Endodontic Journal, 44, 792-799, 2011. Chlorine-containing solutions are used for broad disinfection purposes. Water disinfection literature suggests that their disinfectant action depends on pH values as this will influence the available free chlorine forms. Hypochlorous acid (HOCl) has been suggested to have an antimicrobial effect around 80-100 times stronger than the hypochlorite ion. The aim of this paper was to review the influence of pH changes on the efficacy of chlorine-containing endodontic irrigating solutions. An electronic and hand search (articles published through to 2010, including 'in press' articles; English language; search terms 'root canal irrigants AND sodium hypochlorite or hypochlorous acid or superoxidized water or electrochemically activated solution'; 'antimicrobial action AND sodium hypochlorite or hypochlorous acid or superoxidized water or electrochemically activated solution'; 'tissue dissolution AND sodium hypochlorite or hypochlorous acid or superoxidized water or electrochemically activated solution'; 'smear layer AND sodium hypochlorite or hypochlorous acid or superoxidized water or electrochemically activated solution') was performed to identify publications that compared chlorine water solutions with different pH. Of 1304 publications identified, 20 were considered for inclusion in the review. The search resulted in the retrieval of articles studying sodium hypochlorite (NaOCl), superoxidized waters (SOW) and sodium dichloroisocyanurate (NaDCC). Regarding antimicrobial efficacy, the literature suggested that reducing the pH value of NaOCl to between 6 and 7.5 would lead to improved action; SOW was described as having a lower antimicrobial effect. The tissue dissolution activity NaOCl decreased when the pH reached values between 6 and 7.5; NaDCC and SOW had no clinically relevant tissue dissolution capability. Chlorine solutions of different characteristics appeared to have some cleaning efficacy although they should to be used in conjunction with chelating and/or detergent agents. [ABSTRACT FROM AUTHOR]

This study investigates the potential of 36Cl in tracing young groundwater with residence times of up to ∼50 years. Groundwater samples were obtained from 16 irrigation wells in paddy fields located within an upland-lowland system in the Yoro River basin, Central Japan. The 36Cl/Cl ratios were in the range of 17 to 362 x 10-15. Among the samples with higher Cl- concentrations (>10 mg/L), two samples showed high nitrate concentrations as well (>30 mg/L). Except for these samples, the distribution of 36Cl in groundwater was essentially consistent with previous tritium concentration data measured in 1982 and 1994, considering the time that has elapsed since these earlier measurements were performed. 36Cl/Cl values were less than 30 x 10-15 in lowland areas, with higher values in and around upland areas. The results indicate longer residence times in the regional groundwater flow system (>50 years) than those estimated in previous studies, especially in the area west of the Yoro River. The results demonstrate the ability of 36Cl to trace young groundwater flow, particularly because high values of bomb-derived 36Cl/Cl are easily discriminated from pre-bomb water with low 36Cl/Cl values. Because of its very long half-life (3.01 x 105 years), 36Cl remains even after tritium is no longer available. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to understand the influence of specific steps on genotoxicity and toxicity during surface water treatment in a water treatment plant in China with liquid chlorine as the disinfectant. The study shows that prechlorination and postchlorination steps increase DNA damage and oxidative stress. It highlights the usefulness of comet and oxidative stress assays in evaluating surface water genetoxicity during drinking water treatment.

With the national economic development, China's transportation infrastructure has also made great progress, particularly in the highway. How to reduce the accident consequence that occurred in the highway tunnel has been the tropical topic in China. The liquid Chlorine accidental leakage in highway tunnel was exemplified for the poisonous gas dispersion consequence analysis using computational fluid dynamics. First, the GAMBIT code was used to create geometrical models and generate meshes. Second, by using the FLUENT code, the Chlorine gas dispersion in the highway tunnel was simulated and the scenarios with different leak sources were discussed. Case study shows that the FLUENT code was useful on the simulation of gas dispersion in highway tunnel that serves the prerequisite for the further research. [ABSTRACT FROM AUTHOR]

Abstract: Unpleasant taste and especially chlorine flavor is one of the most common reasons advocated for choosing tap water alternatives as drinking water. As a consequence, the putative link between sensitivity to chlorine flavor and tap water consumption is an issue in drinking water habits studies. In the present study, we set out to examine such a link following a strategy in which we measured chlorine flavor perception at threshold and supra-threshold level for two groups of participants selected on their drinking water consumption habits. The first group included exclusive tap water consumers and the second group included exclusive bottled water consumers. In a first experiment, we used the constant stimuli procedure to evaluate the chlorine flavor detection threshold of a group of 20 tap water consumers and a group of 20 non-consumers. In a second experiment, a group of 18 tap water consumers and a group of 17 non-consumers evaluated supra-threshold flavor intensity, liking and acceptability for eight chlorinated solutions (0–10mg/L Cl2). The results revealed no significant difference in chlorine flavor detection threshold and supra-threshold sensitivity between tap water consumers and non-consumers. Nevertheless, tap water consumers showed a higher liking score for chlorinated solutions and were found to be more inclined to accept these solutions as drinking water. Taken together these findings suggested that consumers may disparage chlorine flavor in drinking water on the basis of their tap water cognitive representation. [Copyright &y& Elsevier]

Abstract: The formation of disinfection by-products (DBPs) from chlorination and monochloramination of treated drinking waters was determined. Samples were collected after treatment at 11 water treatment works but before exposure to chlorine or monochloramine. Formation potential tests were carried out to determine the DBPs formed by chlorination and monochloramination. DBPs measured were trihalomethanes (THMs), haloacetic acids (HAAs), halonitromethanes (HNMs), haloacetonitriles (HANs), haloaldehydes (HAs), haloketones (HKs) and iodo-THMs (i-THMs). All waters had the potential to form significant levels of all the DBPs measured. Compared to chlorine, monochloramination generally resulted in lower concentrations of DBPs with the exception of 1,1-dichloropropanone. The concentrations of THMs correlated well with the HAAs formed. The impact of bromine on the speciation of the DBPs was determined. The literature findings that higher bromide levels lead to higher concentrations of brominated DBPS were confirmed. [Copyright &y& Elsevier]

The fate of organophosphorus (OP) pesticides in the presence of aqueous chlorine was investigated under simulated drinking water treatment conditions. Intrinsic rate coefficients were found for the reaction of hypochlorous acid (kHOCI,OP) and hypochlorite ion (kOCI,OP) for several OP pesticides. The reaction of hypochlorous acid (HOCI) with each OP pesticide was relatively rapid near neutral pH, kHOCI,OP = 0.86 - 3.56 × 106 M-1h-1. HOCI reacts at the thiophosphate (P = S) moiety of the OP pesticide resulting in the formation of the corresponding oxon (P = U), which is more toxic than the parent pesticide. Hypochlorite ion (OCl-) was found not to oxidize OP pesticides but act like a nucleophile accelerating hydrolysis, kOCI,OP = 37,3-15 910 M-1h-1. Both the kHOCI,OP and the kOCI,OP were found to correlate well with molecular descriptors within each subgroup of the OP pesticide class. A model was developed to predict the transformation of OP pesticides in the presence of aqueous chlorine. With hydrolysis rate coefficients, the transformation of OP pesticides under drinking water treatment conditions was found to be adequately predicted. The structure-activity relationships and model developed here could be used by risk assessors to determine exposure to OP pesticides and their transformation products in potable water. [ABSTRACT FROM AUTHOR]

To assist in emergency response decisions and planning in case of releases of pressurized liquefied chlorine from railroad tank cars in industrial sites and cities, the FLACS Computational Fluid Dynamics (CFD) model has been used to simulate the transport and dispersion of the dense chlorine cloud. Two accident locations are studied: an actual railcar accident at an industrial site in Festus, MO, and a hypothetical railcar accident at a rail junction in the Chicago urban area. The results show that transport of a large dense gas release at ground level in an industrial site or large city could initially extend a hundred meters or more in the upwind and crosswind directions. The dense cloud may follow terrain drainage, such as river channels. Near the source, the obstacles tend to slow down the dense gas cloud and may constrain it and cause increased concentrations. Farther downwind, the obstacles may cause enhanced mixing and dilution once the cloud has grown larger. In some cases, significant amounts of cloud mass may become “trapped” in obstacle wakes for many minutes after the main cloud has passed. Although the CFD model can account for the details of the flow and dispersion much better than standard widely-used simple dense gas models, many similarities are found among the various models in their simulated variations with downwind distance of the maximum cloud centerline concentration. [Copyright &y& Elsevier]

Minimally processed fruits and vegetables (MPFV) have a short shelf-life due to their metabolism and the action of spoilage microorganisms. Chlorine dioxide is a powerful oxidizing agent that can be used as decontaminant. It does not form significant amounts of chlorinated by-products like as do chlorine. This article revises the characteristics of chlorine dioxide, the basis of its antimicrobial action, and its effect on microorganisms and on the sensory quality and shelf-life of fresh produce and mainly MPFV. Moreover, it discusses its effects on the physiology and nutritional quality of MPFV, and provides information on its toxicity and legal status. [Copyright &y& Elsevier]

Abstract: Perchlorate-reducing bacteria fractionate chlorine stable isotopes giving a powerful approach to monitor the extent of microbial consumption of perchlorate in contaminated sites undergoing remediation or natural perchlorate containing sites. This study reports the full experimental data and methodology used to re-evaluate the chlorine isotope fractionation of perchlorate reduction in duplicate culture experiments of Azospira suillum strain PS at 37 °C (Δ37ClCl−–ClO4 − ) previously reported, without a supporting data set by Coleman et al. [Coleman, M.L., Ader, M., Chaudhuri, S., Coates, J.D., 2003. Microbial Isotopic Fractionation of Perchlorate Chlorine. Appl. Environ. Microbiol. 69, 4997–5000] in a reconnaissance study, with the goal of increasing the accuracy and precision of the isotopic fractionation determination. The method fully described here for the first time, allows the determination of a higher precision Δ37ClCl−–ClO4 − value, either from accumulated chloride content and isotopic composition or from the residual perchlorate content and isotopic composition. The result sets agree perfectly, within error, giving average Δ37ClCl−–ClO4 − =−14.94±0.15‰. Complementary use of chloride and perchlorate data allowed the identification and rejection of poor quality data by applying mass and isotopic balance checks. This precise Δ37ClCl−–ClO4 − value can serve as a reference point for comparison with future in situ or microcosm studies but we also note its similarity to the theoretical equilibrium isotopic fractionation between a hypothetical chlorine species of redox state +6 and perchlorate at 37 °C and suggest that the first electron transfer during perchlorate reduction may occur at isotopic equilibrium between an enzyme-bound chlorine and perchlorate. [Copyright &y& Elsevier]

Grid-structured ZnO microsphere arrays assembled by uniform ZnO nanorods were fabricated by noncatalytic chemical vapor deposition, taking advantage of morphologies of alumina nanowire pyramid substrates and ZnO oriented growth habits. Every ZnO microsphere (similar to the micropapilla on a lotus leaf surface) is assembled by over 200 various oriented ZnO nanorods (similar to the hairlike nanostructures on mircopapilla of a lotus leaf). This lotus-leaf-like ZnO micro-nanostructure films reveal superhydrophobicity and ultrastrong adhesive force to liquid. The realization of this hierarchical ZnO nanostructure film could be important for further understanding wettability of biological surfaces with micro-nanostructure and application in microfluidic devices. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to examine the potential downstream benefits of sequential disinfection to control the persistence of Escherichia coli under conditions relevant to drinking water distribution systems. Eight annular reactors (four polycarbonate and four cast iron) were setup in parallel to address various factors that could influence biofilm growth in distribution systems. Eight reactors were treated with chlorine, chlorine dioxide and monochloramine alone or in combination with UV to examine the effects on Escherichia coli growth and persistence in both the effluent and biofilm. In general, UV-treated systems in combination with chlorine or chlorine dioxide and monochloramine achieved greater log reductions in both effluent and biofilm than systems treated with chlorine-based disinfectants alone. However, during UV–low chlorine disinfection, E. coli was found to persist at low levels, suggesting that the UV treatment had instigated an adaptive mutation. During UV–chlorine-dioxide treatment, the E. coli that was initially below the detection limit reappeared during a low level of disinfection (0.2mg/L) in the cast iron systems. Chloramine was shown to be effective in disinfecting suspended E. coli in the effluent but was unable to reduce biofilm counts to below the detection limit. Issues such as repair mechanism of E. coli and nitrification could help explain some of these aberrations. Improved understanding of the ability of chlorine-based disinfectant in combination with UV to provide sufficient disinfection will ultimately effect in improved management and safety of drinking water. [Copyright &y& Elsevier]

M5(PO4)3Cl:Eu(M: Sr, Ca) chlorapatites were prepared by solid-state reaction with NH4Cl and CaCl2 as chlorine sources, respectively. Phase formation and luminescent properties strongly depended on chlorine sources and firing atmosphere. With NH4Cl, β-Ca3(PO4)2 as well as Ca5(PO4)3Cl was produced, while a single phase Ca5(PO4)3Cl could be achieved with CaCl2. Ca5(PO4)3Cl:Eu3+ prepared at N2 atmosphere exhibited a red emission around 613 nm with 390 nm excitation, while, under the reduction circumstance, Ca5(PO4)3Cl:Eu2+ showed a blue emission around 460 nm with 370 nm excitation. The substitution of Sr2+ for Ca2+ caused the blue-shift of emission wavelength due to the weak crystal field. [ABSTRACT FROM AUTHOR]

Abstract: The effects of the preparation method (deposition–precipitation, incipient-wetness, combustion) on the structure and redox properties of 1% Au/CeO2 catalyst have been probed by TPR, XRD, and TEM techniques. The catalytic pattern in total (COX) and selective (SCOX) CO oxidation has been assessed by temperature programmed reaction tests in the range 273–473K. Controlling residual chlorine, the synthesis route determines the strength of the Au–CeO2 interaction which affects both the reduction of the active phase and the CO oxidation functionality. Removal of chlorine by washing in a diluted alkaline solution enables then an easy reduction of Au precursor levelling off the reactivity of the Au/CeO2 catalysts. [Copyright &y& Elsevier]

Discusses a study on the effect of repeated applications of chlorine solutions to clogs manufactured from high density polyurethane worn by healthcare personnel. Overview of the procedure concerning blood spills; Details on observations made over applications of chlorine solutions to soles, uppers and part of the lining of clogs; Recommendation of a statement to be included on the product packaging or in the leaflet that will accompany the product.

Abstract: A new PPV derivative, poly(2-phenoxy p-phenylene vinylene)(PO-PPV), has been synthesized via the chlorine precursor route (CPR). PO-PPV and its chlorine precursor polymer were fully characterized by thermal (TGA and DSC), mechanical and spectroscopic (UV–vis, PL and IR) methods. The results indicate that the precursor polmer and the yellow-green light-emitting PO-PPV have excellent stability and mechanical properties. The easily processible precursor is stable at room temperature and therefore has a better shelf-life than PPV synthesized via the sulfonium precursor route. Thermal conversion provides high quality films, relatively free of oxidative defects. [Copyright &y& Elsevier]

A new construction is provided for a liquid chlorine level gauge in which the float has the shape of a sphere and the inductance coil of the sensor is made as a differentially-transformed stepped-section scheme that makes it possible to reduce the unmeasured band to the bottom of the vessel. [ABSTRACT FROM AUTHOR]

A new chlorine-containing phenoloid, named capitulatin A, has been isolated from the rhizomes of Curculigo capitulata . Its structure was established as 2,4-dichloro-3-methyl-5-hydroxy-6-methoxylphenol-β- d -xylopyranosyl (1→6)-β- d -glucopyranoside ( 1 ) on the basis of the spectral data and chemical evidence. [ABSTRACT FROM AUTHOR]

Non-equilibrium molecular dynamics (NEMD) simulations play a major role in characterizing the rheological properties of fluids undergoing shear flow. However, all previous studies of flows in molecular fluids either use an 'atomic' thermostat which makes incorrect assumptions concerning the streaming velocity of atoms within their constituent molecules, or they employ a centre of mass kinetic (COM) thermostat which only controls the temperature of relatively few degrees of freedom (3) in complex high molecular weight compounds. In the present paper we show how recently developed configurational expressions for the thermodynamic temperature can be used to develop thermostatting mechanisms which avoid both of these problems. In this work, we propose a thermostat based on a configurational expression for the temperature and apply it to NEMD simulations of chlorine undergoing Couette flow. The results so obtained are compared with those obtained using a COM kinetic thermostat. At equilibrium the properties of systems thermostatted in the two different ways are of course equivalent. We show that the two responses only differ far from equilibrium. In particular, we show that the formation of a string phase for extremely high shear rates is an artefact of the COM thermostat. At the largest shear rates studied with the configurational thermostat, no string phase is observed. [ABSTRACT FROM AUTHOR]

The variables that affect bleaching in home laundering have been studied in an effort to develop recommendations for more effective, safer bleaching. The study was confined to the effects of liquid hypochlorite bleach on cotton since liquid chlorine bleach is used in most households. The variables studied were bleach concentration in the wash bath, the bath temperature during bleaching and the duration of the bleach cycle. [ABSTRACT FROM AUTHOR]