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Model za procenu rizika amonijaka u logističkim podsistemima / Ammonia risk assessment model in logistical subsystemsZiramov Nikola 19 November 2020 (has links)
<p>Razvijen je model za procenu rizika amonijaka u logistiĉkim podsistemima. Navedene su osnovne parametarske i neparametarske statistiĉke karakteristike akcidenata sa amonijakom po logistiĉkim podsistemima. Raspodele hospitalizovanih, nehospitalizovanih i nastradalih uĉesnika akcidenata imaju homogene zakone, zasnovane na Vejbulovoj raspodeli. Hospitalizovani preminuli uĉesnici su raspodeljeni po Binomnoj raspodeli. Najveći broj uĉesnika u akcidentu amonijaka je ustanovljen u logistiĉkom podsistemu proizvodnje, proseĉno 8,8750. Kritiĉan rizik amonijaka je ustanovljen u logistiĉkom podsistemu pretovara.</p> / <p>Ammonia risk assessment model in logistical subsystems has been developed. Basic parametric and non-parametric statistical characteristics of ammonia accidents by logistic subsystems are given. Distributions of hospitalized, non-hospitalized, and injured accident participants have homogeneous laws, based on the Weibull distribution. Hospitalized deceased participants were distributed by Binomial distribution. The largest number of participants in the ammonia incident was established in the logistics subsystem of production, with an average of 8.8750. Critical risk of ammonia is established in the logistic subsystem of reloading.</p>
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Knowledge-based classification scheme for regulating the flow of hazardous materials through tunnelsBasilio, Bernardo I. January 1987 (has links)
Safety is a major concern for tunnel operators. Local authorities responsible for tunnel facilities are concerned with developing restrictions for hazardous materials passing through the facility that will reduce the risk of death and injury, to an extent that these restrictions do not burden commerce unnecessarily.
Hazardous material regulatory controls for tunnels are extensive, detailed, and subject to constant changes. The general lack of expertise in tunnel personnel and the lack of a scientific basis leading to the development of these regulations have created problems to local tunnel authorities when updating the restrictions, or when faced with new materials introduced by the industry. Traditionally, most regulatory restrictions enforced both at the federal and the local level are based exclusively on subjective estimation by a panel of experts and on political influence. Experts, however, are not readily available and are expensive to maintain. The need for immediate decisions has constrained tunnel operators to rely on their own intuition in addressing real time transport safety problems in tunnel facility.
To address some of these problems, this research investigates the application of knowledge engineering tools to develop a consultative regulatory control system. Specifically, this study presents a structural framework for developing a knowledge-based expert system as an aid to decision-making in tunnel transport safety.
The regulatory problem is modeled as a classification type of problem, which lends itself neatly to an expert system application. Heuristic problem solver which is commonly used in solving classification problem involves the systematic matching of the attributes of an unknown entity to a set of pre-defined solutions. For this study's application, the regulatory groupings inherent in existing tunnel regulations are the basis for developing the solution space. The computer program developed uses knowledge which specifies the appropriate regulation applicable to a new commodity based on the material's physical and chemical properties. / M.S.
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The use of purified enzymes for the early assessment of toxicityPfaff, John F. January 1982 (has links)
The increasing level and dispersion of toxic chemicals in the environment has stimulated a need for accurate methods capable of detecting and quantifying the activity of toxicants. The primary objective of this study was to determine, through in vitro tests, the potential of three purified enzymes: α-chymotrypsin, acid phosphatase, and carbonic anhydrase for use in the early assessment of toxicants at environmentally significant levels. Activities of α-chymotrypsin and acid phosphatase were measured spectrophotometrically, while carbonic anhydrase activities were determined through monitoring a pH change. The chemical agents investigated included several heavy metals, common herbicides and pesticides, and various environmentally significant anions. In addition, several techniques were explored to amplify enzyme response to chemical agents.
The results of the study demonstrated that α-chymotrypsin did not significantly respond to cadmium, nickel, or 2,4-D, and consequently, does not appear to be useful in indicating potential toxicity problems associated with these agents.
The acid phosphatase enzyme system appears to be useful in signaling the presence of low levels of certain anions (fluoride at 0.45 mg/ℓ and nitrate at 7.3 mg/ℓ), but does not appear to have potential for detecting toxic activity due to cadmium, nickel, or 2,4-D. Enzyme inhibition induced by fluoride at 37°C was not altered by changing the assay temperature to 50°C.
The results of the experiments with carbonic anhydrase show that the enzyme does not appear to be affected by cadmium or nickel ions. However, enzyme activity was inhibited by fluoride (4.5 mg/ℓ), sulfide (0.5 mg/ℓ), and nitrate (73 mg/ℓ). Enzyme inhibition was also induced by 10 mg/ℓ of atrazine, malathion, or carbaryl, and 150 to 500 mg/ℓ of 2,4-D. Inhibitory effects induced by sulfanilamide appeared to be slightly enhanced by the addition of Cd²⁺, Ni²⁺, or Zn²⁺ cations. These findings, although preliminary, suggest that carbonic anhydrase demonstrates potential for signaling the presence of anions, and appears to be useful in indicating potential toxicity problems due to pesticides and herbicides. / Master of Science
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An examination of the determinants of perceived risk and acceptability of hazardous products and activitiesOglethorpe, Janet E. January 1988 (has links)
This research sought to better understand the antecedents of consumers' perceptions of risk (health and safety risks specifically), and the relationship between the perceived risk of an option, and judgments about the acceptability of that option. The specific objective of the proposed research was to build a model of risk perception and risky option acceptability for hazardous products and activities (i.e., that present downside risks to a consumer's health and safety), using several variables that have been postulated to be important, using a multiple linear regression model building approach. One goal was to integrate the study of perceived risk in consumer behavior with various concepts and models of risk perception and risk acceptability from the behavioral decision sciences, an integration suggested previously by Jacoby (1981). Emphasis was placed on conceptual and methodological issues that confront researchers from either domain that need to be resolved if risk is to occupy a central place in marketing theory. Two of the variables included in the study of the determinants of perceived risk comprise the conceptual definition of perceived risk used in this research: probability of a negative outcome, and severity of a negative outcome. Specifically, both were hypothesized to be positively correlated with perceptions of risk.
Six additional variables were also examined as determinants of perceived risk. Given the definition of risk used in this research, these variables relate to either or both of the constructs probability and severity, and implicitly were also hypothesized to be significant determinants of risk perception. The variable examined that relates to probability exclusively was controllability. Specifically, a negative relationship was hypothesized between the perceived risk of a product and the controllability of the negative outcome associated with that product. Variables which relate to severity exclusively include reversibility, dreadedness, and immediacy. Specifically, judgments of negative consequences as immediate, dreaded, and irreversible were hypothesized to be positively correlated with perceptions of risk. Finally, two variables that relate to both probability and severity included availability and catastrophic potential. Specifically, there should be a positive relationship between the perceived risk of a product and the availability and catastrophic potential of the negative outcome associated with that product. All hypotheses with the exception of those relating to immediacy were supported; the hypotheses relating confidence to acceptability was only partially supported. All variables with the exception of immediacy were concluded to belong in a comprehensive model of perceived risk and option acceptability. / Ph. D.
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Respiratory health hazards of artists in their studiosMedford, Marsha Kay January 1989 (has links)
Artists are exposed to numerous respiratory health hazards in the production of art. Little is known of artists' studio behaviors or of their health beliefs related to respiratory toxins. The Health Belief Model hypothesizes that individuals require a minimal level of relevant health motivation and knowledge before attempting to prevent a health condition, as well as a perception of their vulnerability to health conditions they view as threatening, conviction in the efficacy of preventive behaviors, and a perception that recommended preventive action entails few difficulties. This descriptive and exploratory study, conducted within the framework of the Health Belief Model, seeks to determine artists' knowledge, health beliefs, and preventive studio practices related to occupational respiratory health risks.
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Pyrolysis of chlorinated organic chemicals.Pillay, Kleantha. January 2001 (has links)
At present, South Africa has inadequate technology to destroy its hazardous waste, with
approximately 18000 litres of chlorinated hazardous waste stored in this country. Approximately
800 tons of banned or obsolete chemicals are to be sent to Pontypool. Wales, for incineration, at a
considerable cost. Because of the toxic nature of chlorinated waste and their long-term effects on
the environment , a sustainable method of dealing with this type of waste is essential.
Gas phase destruction of methylene chloride, trichlorobenzene and lindane by pyrolysis (i.e.
heating in the absence of oxygen) was attempted. Destruction was effected by high temperature
thermal degradation of molecules into free radicals. These radicals then combine to form hydrogen
chloride and carbon as major products. This method was chosen so as to eliminate the possible
formation of highly toxic oxygenated derivatives such as polychlorinated dibenzofurans and
dibenzodioxins that can be formed during incineration if strict control is not excercised.
The reactor assembly was built in the Department of Chemical Engineering at the University of
Natal. 11 incorporates aspects of many different previously designed reactors, as discussed in the
text. Heat for the reactions was supplied by induction. A high frequency induction unit supplied
current to a copper coil. The resulting magnetic field induced current to flow in a susceptor housed
within the copper coil. The susceptor in this case was a graphite tube, which served as both the
heating element and the thermal radiation source, in addition to forming the walls of the reaction
zone. Up and down stream processes were designed and experiments were carried out in which
reaction temperatures (348-1400°C) and residence times (1.3-5.6 seconds) were varied.
Destruction efficiencies of 100% and 99.99% were obtained for methylene chloride and
trichlorobenzene respectively, with inert argon used as the carrier gas. These destruction
efficiencies comply with the 99.99% stipulated by the United States Conservation and Recovery
Act. A cause for concern was the formation of chlorinated benzenes and naphthalenes. Destruction
of lindane proved unsuccessful due to limitations in the vapourisation and feed system and will
have to be investigated further. The method of induction heating was evaluated to be 98.9%
thermally efficient.
Raw material and utility consumption per ton of waste destroyed by the pyrolysis process was
compared to values for incineration as well as the plasma arc and catalytic extraction processes.
Consumption for pyrolysis compares favourably with all three processes and suggests that the
process could be competitive.
Claims to the success of the technology on a wide scale are limited by the small number of
compounds that were successfully pyrolysed. Results do however indicate much promise for this
technology to be used as a fi nal chlorinated waste destruction unit on an existing process.
Modifications to the existing reactor to improve product recovery and analys is will allow for
temperature and residence time optimisation for a variety of wastes. Additional in strumentation
and process control will allow for kinetic studies to be undertaken in future. This project should be
considered as the first step in an ongoing series of research and subsequent improvements to the
technology presented here. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.
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Improvised incendiary devices risk assessment, threats, vulnerabilities and consequencesRaynis, Stephen A. 09 1900 (has links)
CHDS State/Local / The current trend in terrorist tactics is the use of simple, inexpensive and conventional weapons. One such weapon is improvised incendiary devices (IIDs). The homeland security community has underestimated the magnitude of the threat. Policy makers must recognize the potential for terrorist cells to use IIDs to create terror and fear in the public. IIDs have the potential to create devastating fires resulting in mass casualties. In addition to evaluating the risk of an IID attack and determining the state of preparedness of first responders, this thesis includes a proposal for the creation of two new national planning scenarios, urban and wildland conflagrations or firestorms. Recommendations will include incendiary protocols in the weapon of mass destruction matrix as represented by "I" in CBIRNE. This organizational change can be applied to the homeland security strategies, lexicons and documents of Federal, State, and local governments and the private sector to address the IID threat. This thesis is intended to serve as a catalyst for the Department of Homeland Security to set policy that will decrease vulnerabilities and consequences of this lesser-known threat. / Battalion Chief, New York City Fire Department (FDNY)
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Analysis of Mesh Strategies for Rapid Source Location in Chemical/Biological AttacksHoward, Patricia Ann 30 April 2004 (has links)
Currently, researchers at Sandia National Laboratories are creating software that is designed to determine the source of a toxic release given sensor readings of the toxin concentration at fixed locations in the building. One of the most important concerns in solving such problems is computation time since even a crude approximation to the source, if found in a timely manner, will give emergency personnel the chance to take appropriate actions to contain the substance. The manner in which the toxin spreads depends on the air flow within the building. Due to the turbulence in the air flow, it is necessary to calculate the flow field on a fine mesh. Unfortunately, using a fine mesh for every calculation in this problem may result in prohibitively long computation times when other features are incorporated into the model. The goal of this thesis is to reduce the computation time required by the software mentioned above by applying two different mesh coarsening strategies after the flow field is computed. The first of these strategies is to use a uniformly coarse mesh and the second is to use our knowledge of the air flow in the building to construct an adaptive mesh. The objective of the latter strategy is to use a fine mesh only in areas where it is absolutely necessary, i.e., in areas where there is a great change in the flow field.
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Toxicity identification evaluation of effluent from dyeing industry =: 染廠廢水的毒性鑒定評估研究. / 染廠廢水的毒性鑒定評估研究 / Toxicity identification evaluation of effluent from dyeing industry =: Ran chang fei shui de du xing jian ding ping gu yan jiu. / Ran chang fei shui de du xing jian ding ping gu yan jiuJanuary 2003 (has links)
by Chung Ho Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 127-141). / Text in English; abstracts in English and Chinese. / by Chung Ho Yan. / Acknowledgments --- p.i / Abstract --- p.ii / Table of Contents --- p.v / List of Figures --- p.xi / List of Plates --- p.xiv / List of Tables --- p.xv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Textile-Dyeing Industry in Hong Kong --- p.1 / Chapter 1.2 --- Processes Involved in Dyeing Industry --- p.3 / Chapter 1.2.1 --- Desizing --- p.3 / Chapter 1.2.2 --- Scouring --- p.3 / Chapter 1.2.3 --- Bleaching --- p.3 / Chapter 1.2.4 --- Mercerizing --- p.4 / Chapter 1.2.5 --- Dyeing and Printing --- p.4 / Chapter 1.2.6 --- Finishing --- p.4 / Chapter 1.3 --- Characterization of Wastewater of Dyeing Industry --- p.5 / Chapter 1.4 --- Toxicity of Effluent from Textile-Dyeing Industry --- p.9 / Chapter 1.5 --- Related Environmental Legislation --- p.9 / Chapter 1.6 --- Chemical Specific Approach and Toxicity Based Approach --- p.11 / Chapter 1.7 --- Whole-Effluent Toxicity (WET) Test --- p.13 / Chapter 1.8 --- Toxicity Identification Evaluation --- p.14 / Chapter 1.8.1 --- Phase I - Toxicity Characterization --- p.15 / Chapter 1.8.2 --- Phase II - Toxicity Identification --- p.15 / Chapter 1.8.3 --- Phase III - Toxicity Confirmation --- p.18 / Chapter 1.9 --- Toxicity Identification Evaluation on Effluent from Textile-Dyeing Industry --- p.19 / Chapter 1.10 --- Organisms Used for Toxicity Identification Evaluation --- p.20 / Chapter 1.11 --- Selection of Organisms for Bioassays --- p.20 / Chapter 2. --- OBJECTIVES --- p.24 / Chapter 3. --- MATERIALS AND METHODS --- p.25 / Chapter 3.1 --- Sources of Samples --- p.25 / Chapter 3.2 --- Whole Effluent Toxicity Test - Baseline Toxicity Test --- p.28 / Chapter 3.2.1 --- Microtox® test --- p.28 / Chapter 3.2.2 --- "Survival test of the marine amphipod, Hyale crassicornis" --- p.29 / Chapter 3.2.3 --- "Survival test of the brine shrimp, Artemia franciscana" --- p.33 / Chapter 3.2.4 --- "Survival test of the freshwater water flea, Daphnia magna" --- p.36 / Chapter 3.3 --- Toxicity Identification Evaluation ´ؤ Phase I Toxicity Characterization --- p.40 / Chapter 3.3.1 --- pH adjustment filtration test --- p.41 / Chapter 3.3.2 --- pH adjustment aeration test --- p.42 / Chapter 3.3.3 --- pH adjustment cation exchange test --- p.43 / Chapter 3.3.4 --- pH adjustment anion exchange test --- p.44 / Chapter 3.3.5 --- pH adjustment C18 solid phase extraction (C18 SPE) test --- p.45 / Chapter 3.3.6 --- pH adjustment XAD-2 solid phase extraction (XAD-2 SPE) test --- p.46 / Chapter 3.4 --- Toxicity Identification Evaluation - Phase II Toxicity Identification --- p.47 / Chapter 3.4.1 --- Determination of anions --- p.48 / Chapter 3.5 --- Toxicity Identification Evaluation ´ؤ Phase III Toxicity Confirmation --- p.50 / Chapter 3.5.1 --- Mase balance test --- p.50 / Chapter 3.5.2 --- Spiking test --- p.51 / Chapter 4. --- RESULTS --- p.52 / Chapter 4.1 --- Characteristics of Samples --- p.52 / Chapter 4.2 --- Whole Effluent Toxicity Test - Baseline Toxicity Test --- p.52 / Chapter 4.2.1 --- Toxicity of effluent sample determined by the Microtox® test --- p.52 / Chapter 4.2.2 --- Toxicity of effluent samples determined by Hyale crassicornis survival test --- p.52 / Chapter 4.2.3 --- Toxicity of effluent samples determined by Artemia franciscana survival test --- p.57 / Chapter 4.2.4 --- Toxicity of effluent samples determined by Daphnia magna survival test --- p.51 / Chapter 4.3 --- Toxicity Identification Evaluation - Phase I Toxicity Characterization --- p.57 / Chapter 4.3.1 --- Toxicity characterization of effluent samples determined by Hyale crassicornis survival test --- p.60 / Chapter 4.3.2 --- Toxicity characterization of effluent samples determined by Artemia franciscana survival test --- p.68 / Chapter 4.3.3 --- Toxicity characterization of effluent samples determined by Daphnia magna survival test --- p.68 / Chapter 4.4 --- Toxicity Identification Evaluation ´ؤ Phase II Toxicity Identification --- p.72 / Chapter 4.4.1 --- Baseline anion concentrations in effluent samples --- p.75 / Chapter 4.4.2 --- Sample1 --- p.75 / Chapter 4.4.3 --- Sample2 --- p.75 / Chapter 4.4.4 --- Sample3 --- p.75 / Chapter 4.4.5 --- Sample4 --- p.81 / Chapter 4.4.6 --- Sample5 --- p.81 / Chapter 4.4.7 --- Sample6 --- p.81 / Chapter 4.5 --- Toxicity Identification Evaluation 一 Phase III Toxicity Confirmation --- p.85 / Chapter 4.5.1 --- Mass balance test results --- p.85 / Chapter 4.5.2 --- Spiking test results --- p.96 / Chapter 5. --- DISCUSSION --- p.102 / Chapter 5.1 --- Whole Effluent Toxicity Test ´ؤ Baseline Toxicity Test --- p.102 / Chapter 5.1.1 --- Toxicity of effluent sample determined by the Microtox® test --- p.102 / Chapter 5.1.2 --- Toxicity of effluent samples determined by Hyale crassicornis survival test --- p.103 / Chapter 5.1.3 --- Toxicity of effluent samples determined by Artemia franciscana survival test --- p.104 / Chapter 5.1.4 --- Toxicity of effluent samples determined by Daphnia magna survival test --- p.104 / Chapter 5.2 --- Toxicity Identification Evaluation ´ؤ Phase I Toxicity Characterization --- p.105 / Chapter 5.2.1 --- pH adjustment filtration test --- p.105 / Chapter 5.2.2 --- pH adjustment aeration test --- p.106 / Chapter 5.2.3 --- pH adjustment cation exchange test --- p.106 / Chapter 5.2.4 --- pH adjustment anion exchange test --- p.106 / Chapter 5.2.5 --- pH adjustment C18 solid phase extraction (C18 SPE) test --- p.107 / Chapter 5.2.6 --- pH adjustment XAD-2 solid phase extraction (XAD-2 SPE) test --- p.107 / Chapter 5.3 --- Toxicity Identification Evaluation - Phase II Toxicity Identification --- p.107 / Chapter 5.3.1 --- Efficiency on chemical reduction of pH adjustment filtration test --- p.109 / Chapter 5.3.2 --- Efficiency on chemical reduction of pH adjustment aeration test --- p.109 / Chapter 5.3.3 --- Efficiency on chemical reduction of pH adjustment cation exchange test --- p.109 / Chapter 5.3.4 --- Efficiency on chemical reduction of pH adjustment anion exchange test --- p.109 / Chapter 5.3.5 --- Efficiency on chemical reduction of pH adjustment CI8 SPE test --- p.109 / Chapter 5.3.6 --- Efficiency on chemical reduction of pH adjustment XAD-2 SPE test --- p.110 / Chapter 5.4 --- Toxicity Identification Evaluation - Phase III Toxicity Confirmation --- p.110 / Chapter 5.4.1 --- Mass balance test results --- p.110 / Chapter 5.4.2 --- Spiking test results --- p.114 / Chapter 5.5 --- Comparison of Toxicant(s) Identified in the Six Dyeing Industrial Effluents --- p.117 / Chapter 5.6 --- Toxicant(s) Identified in Textile-Dyeing Industrial Effluent --- p.119 / Chapter 5.7 --- "Sources, Fate and Treatment of Sulfite Ion" --- p.120 / Chapter 5.8 --- Toxicity of Sulfite Ion --- p.121 / Chapter 5.9 --- Effect of Salinity on the Toxicity of Sulfite Ion --- p.122 / Chapter 5.10 --- Recommendation --- p.123 / Chapter 6. --- CONCLUSIONS / Chapter 7. --- REFERENCES / Chapter 8. --- APPENDICES
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Gemensamma åtgärder i harmoni? : En beskrivande fallstudie av regional miljöpolitisk koordination mellan nationell och internationell nivå. / Joint efforts in harmony? : A descriptive case study of regional environmental policy coordination between national and international levels.Lind, Patrik January 2008 (has links)
<p> </p><p>The aim and scope of this study is to describe the coordination of joint efforts concerning chemicals and hazardous substances in the Baltic Sea region, between the Swedish Chemicals Agency (KemI) and the land-based pollution group of the Helsinki Commission (HELCOM LAND). Based on the description of the coordination, the second aim is to discuss the consequences for the Swedish Chemicals Agency in its policy shaping work towards a nontoxic environment. A qualitative and descriptive case study method is used for this purpose. Theories of coordination and achievement-inducing criteria for environmental goals are applied to the case. Components and related processes of coordination are applied to the descriptive part of the study, whilst the achievement-inducing criteria are applied in the discussion. The description of the coordination unveils a strong coordination regarding goal selection, goal decomposition and mapping activities to actors. It also confirms an interdependency between the two organisations, based on the fact that they have different institutional leverage, and thus addresses different types of actors. The result of the study shows that the coordination consequences do not lead to an independent Swedish chemicals policy. Due to limited data, the certainty of the conclusions based on the theoretical and empirical evidence found in this study can be discussed, and must therefore be subject to more empirical research.</p><p> </p>
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