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Titanium tetrachloride (TiCl4) is a well-known source of titanium (Ti) for the formation of titanium nitride (TiN) barrier material in the semiconductor interconnection process; however, the reaction of by-products with airborne molecules can cause unexpected pump trips and equipment breakdown from the by-product powder build-up. Plasma scrubbers are used to decompose by-products, but hydrogen chloride (HCl) and nitrogen oxides are produced during and after the process. The process mechanisms change when the temperature and applied power of the heat source change. In this paper, we study the influence of the reactor temperature and applied power to the heat source on the decomposition capacity of TiCl4 in a plasma pretreatment system (PPS). We examine the effect of the temperature and heat source power to understand the reaction mechanisms for the composition and decomposition of gaseous species with chemical reactions through simultaneous methods. We analyzed the system with computational fluid dynamics (CFD) and chemical kinetic simulation to investigate the changes of the system mechanism. Subsequently, we achieved results for the correlation between the temperature of the reactor, power applied to the heat source, composition and decomposition of species, and chemical reaction mechanisms. [ABSTRACT FROM AUTHOR]

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Per- and polyfluoroalkyl substances (PFAS) are a large class of synthetic compounds, many of which are persistent, mobile and toxic (PMT). The sheer number of PFAS makes a substance-by-substance based approach to regulating this group unfeasible. Given the known risks of many PFAS, a precautionary approach (i.e., the Essential Use Concept; EUC) has been called for, whereby any substance is assumed to be harmful and should be phased out, unless it is shown that: (a) the use of this substance is necessary for health and safety, or is critical for the functioning of society and (b) there are no available technically and economically feasible alternatives. While experts, including chemists and toxicologists, are well-placed to assess the second criteria, determining what is necessary for the "functioning of society" requires a wider consideration of societal beliefs and preferences and greater involvement of various interested and affected parties, especially those whose voices are less heard but may be most vulnerable. The aim of the current paper is to provide a preliminary framework and research agenda outlining why and at what points in the essential use decision-making process broader societal perspectives are required, and how such 'social data' can be collected. The ultimate goal is to improve chemicals management by supporting citizens in becoming more informed and engaged participants in relevant debates and policies, including in how to operationalise the EUC. [ABSTRACT FROM AUTHOR]

The formation of hydrogen sulfide (H2S) in petroleum reservoirs by anaerobic microbial activity (through sulfate-reducing microorganisms, SRMs) is called biogenic souring of reservoirs and poses a risk in the petroleum industry as the compound is extremely toxic, flammable, and corrosive, causing devastating damage to reservoirs and associated surface facilities. In this paper, we present a workflow and the tools to assess biogenic souring from a pragmatic engineering perspective. The retention of H2S in the reservoir due to the reactions with iron-bearing rock minerals (e.g., siderite) is shown in a theoretical approach here and supported with literature data. Cases are provided for two fields under secondary (waterflooding) and tertiary flooding with microbial enhanced oil recovery (MEOR). The use of the Monte Carlo method as a numerical modeling tool to incorporate uncertainties in the measured physical/chemical/biochemical data is demonstrated as well. A list of studies conducted with different chemicals alone or in combination with various biocides to mitigate biogenic souring provides an overview of potential inhibitors as well as possible applications. Furthermore, the results of static and dynamic inhibition tests using molybdate are presented in more detail due to its promising mitigation ability. Finally, a three-step workflow for the risk assessment of biogenic souring and its possible mitigation is presented and discussed. [ABSTRACT FROM AUTHOR]

Copyright of Contributions to Tobacco & Nicotine Research is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plastic waste has become a major global concern, due to the widespread use of plastics, resulting in plastic waste accumulation in landfills, and poor plastic waste management that has caused discarded plastics to accumulate in oceans, worldwide. Pyrolysis, a thermochemical treatment technique, offers a sustainable and efficient solution by reducing pollution and recovering valuable energy and products. This paper provides an overview of existing pyrolysis techniques for plastic waste and discusses the parameters that influence product yield and selectivity. It explores the impact of different catalysts on the pyrolysis process and offers a comparative assessment with the conventional pyrolysis. By recovering plastic waste through pyrolysis, the dependence on non-renewable fossil fuels can be reduced, bolstering energy sustainability while mitigating plastic waste's environmental repercussions. This paper also discusses the deactivation and regeneration mechanisms of the catalysts, as well as strategies to optimize liquid oil production from plastic waste, highlighting the potential for utilizing pyrolysis-derived liquid oil as a more sustainable energy source. Lastly, the paper includes a discussion on the future outlook of the pyrolysis industry. This review would provide recommendations for future research directions, enabling researchers and stakeholders to identify key areas of interest and develop new projects accordingly. [Display omitted] • Pyrolysis technology has the capability to convert plastic waste into valuable fuels and chemicals. • A comprehensive review of recent advancements in plastics-to-fuels and chemicals technology was presented. • The product yield and selectivity are determined by operating parameters and catalysts. • Emphasis was placed on the importance and significance of establishing a circular economy for plastics. [ABSTRACT FROM AUTHOR]

• Hemicelluloses-rich aqueous byproducts from WTCPs are often disposed of as waste. • Valorization of hemicelluloses-derived products into fuels, chemicals, and bioproducts. • Circular bioeconomy and use of all biomass processing byproducts from WTCPs. • Challenges to integrate and scale up aqueous byproduct processing in biorefineries. Thermochemical pretreatments are employed prior to energy, chemicals, and fuels production from biomass. Wet thermochemical processes (WTCP) are treatments used to modify biomass properties in water as the primary solvent, with or without added reactants/catalysts. WTCP includes hot water extraction, steam explosion, hydrothermal liquefaction, hydrothermal carbonization (HTC), and supercritical water gasification. WTCP also includes processes that add chemicals to reduce reaction time and improve efficiency, i.e., organosolv, alkali, and low acid pretreatment. Operational parameters in WTCP are usually selected to optimize the yields of sugars after enzymatic hydrolysis of the resulting solids and biogas from the pretreated solids, or to ensure that hydrochar (e.g., from HTC) performs adequately in environmental applications. However, a key byproduct from WTCPs is an aqueous fraction (rich in nutrients, hemicellulose-derived sugars, and chemicals) often disposed of as waste. The necessity of resource conservation and proper management and the need to make WTCP-based biorefineries economically and environmentally sound require using all the byproducts of biomass processing. Options for downstream conversion of the WTCPs' aqueous byproducts are dispersed in the literature. Thus, this paper aims to put together works that report the parameters of WTCPs that allowed removing hemicellulose-derived fractions and nutrients from biomass (either partially or almost entirely), the yields and properties of this aqueous byproduct, methods of characterization, current and expected uses, and the challenges for scaling up WTCPs and using the aqueous stream. The paper focuses on expected and existing methods that allow the valorization of the aqueous fraction and reduce wastes within a circular bioeconomy framework. [ABSTRACT FROM AUTHOR]

Industrial semiconductor electrodeposition plating cells require recirculation of process chemicals with consistent flow and minimal contaminants to prevent defects from developing during film deposition. This manuscript investigates how recirculation nozzle quality and nozzle machining can affect bath chemical uniformity. Computational fluid dynamics simulations are utilized to visualize bath chemical velocities based on variable nozzle conditions in four case studies. Results show that strict quality control of inlet nozzles, in conjunction with proper mounting angles, induce laminar bath flow. Greater fluid uniformity and laminar flow translate to a reduction of in-line defects and increased wafer yield. [ABSTRACT FROM AUTHOR]

The chemical composition, phytochemical contents, and antibacterial potentials of the Eryngium Thyrsoideum Boiss. aerial parts were evaluated. The RP-HPLC-DAD method were applied to determine the phenolic and flavonoid contents of the extract. The hydrodistillation method with a Clevenger apparatus was used to isolate the essential oil, and the analyses of the oil was performed using GC-MS. Using the disc diffusion method and the broth microdilution assay, three gram-negative and six gram-positive bacterial strains were tested to assess the antibacterial effect of oil. The total flavonoid content of the extract was 0.81 ± 0.05 mg of quercetin equivalent per gram of dry plant materials, while its total phenolic content was 0.24 ± 0.01 mg of gallic acid equivalents per g of dry plant materials. According to the phytochemical screening results, phenols, flavonoids, steroids, glycosides, and saponins were detected in the ethyl acetate, n-hexane, and methanolic extracts. Results showed the existence of rutin, quercetin, and benzoic acid in the methanolic extract and revealed 46 compounds that constitute 93.07% of the obtained oil were recognized. Besides, 2,3,6-trimethyl benzaldehyde (24.15%), trans-4,10-epoxy-amorphane (15.55%), longifolene (13.72%), germacrene D (4.76%), 2,3,4-trimethyl benzaldehyde (4.67%), cis-chrysanthenyl acetate (3.3%), caryophyllene oxide (3.26%), and sesquicineole (2.78%) were identified in the oil as the major compounds. The oil showed in vitro significant inhibitory effect on Bacillus pumilus, Bacillus subtilis, and Staphylococcus epidermidis, resulting from its high proportion of sesquiterpenes. Regarding the different bioactive compounds and the antibacterial properties of Eryngium thyrsoideum, this plant can be applied in cosmetic, food, and pharmaceutical products. [ABSTRACT FROM AUTHOR]

The article presents the laboratory and field tests results for the effectiveness of the fungicide Protazox SC (suspension concentrate) against anthracnose and other lupin diseases. The tests have been done in Bryansk region in 2020–2022. The study objects were seedlings and vegetative plants of the narrow-leaved lupin Vityaz variety. The effectiveness of protective and curative properties of the fungicide Protazox SC (azoxistrobine + protioconazole + dipheconazole, 200 + 125 + 60 g/l) was tested for 0.5; 1.0 and 1.5 l/ha consumption rates under laboratory conditions. The biological effectiveness was evaluated according to the number of infected seedlings grown in paper-and-plastic rolls compared to the control variant (fungicide free). The maximal rate of the fungicide – 1.5 l/ha – had the highest biological effectiveness of protective and curative properties (98.7 and 97.4 %); this corresponds to the effectiveness of the reference fungicide Kolosal Pro with the using rate of 0.4 l/ha. In a field test the fungicide Protazox at using rate of 1.5 l/ha was applied for lupin crops at the growing stages of “1-2 pairs of true leaves” and “bud formation” of lupin. The fungicide effectiveness was evaluated compared to the control without treatment. Biological effectiveness of the tested fungicide against anthracnose made 95.8 %, it was 4.5 % higher than of the reference fungicide Kolosal Pro. To the stage of “shiny pod” the number of anthracnose infected pods treated with the fungicide Protazox decreased to 1.5 % compared to 26.5 % in the control variant. Fusarium infection of plants decreased from 24.6 % in the control to 12.0 % in the variant with the fungicide. The spread of gray and white rot on beans decreased by 5.0 and 6.7 times, respectively. The viability of productive plants by the harvesting period increased by 41.3 %. Thanks to the application of the fungicide Protazox SC (1.5 l/ha) the significant narrow-leaved lupin seed yield rise of 0.91 t/ha was obtained (LSD05 = 0.04); the cost recovery was 2.56 rubles.

• Decarbonisation of the industrial sector is key to achieve net-zero emission target on schedule. • For the cement and iron and steel industry, some new technologies which based on their production material(CaO, steel slag) have been gradually developed. • The economic benefits generated by chemical industry can promote the application of carbon reduction technologies in other fields. • The small-scale projects can reduce economic costs through enhancing regional synergy. With the continuous increase in anthropogenic CO 2 emissions, many countries have researched and implemented carbon reduction technologies for large-scale industrial processes. In addition to the power industry, the cement, steel and iron, and chemical production industries are large sources of CO 2 emissions. However, the processes and flue gas characteristics of each industry differ; thus, the carbon capture methods applicable to each industry differ. This paper reviews the key technologies, status, and development trends of carbon reduction methods for each industrial source with a focus on the unique characteristics of each industry. As emission reduction targets become stricter, the large-scale development of carbon reduction demonstration projects will inevitably lead to a decrease in the costs of emission reduction technology. This review would be useful for obtaining an overview of the current progress and future prospect for carbon reduction of nonpower industries in both fundamental research and commercial applications. [ABSTRACT FROM AUTHOR]

Emerging contaminants are chemical compounds present in the environment, particularly in aquatic systems, which are currently not subjected to regulatory measures. This problem occurs when pollutants are introduced into aquatic systems through multiple sources, including wastewater discharge, agricultural runoff, and atmospheric deposition. Products that contain emerging contaminants are classified into 3 categories: pharmaceuticals, personal care products, and endocrine-disrupting chemicals. Several organisms are affected by the accumulation of the chemicals in water bodies. These emerging contaminants have been found to alter the behaviour and development of fish and organisms that form the base of the aquatic food chain. Additionally, they interfere with the ability of organisms to reproduce and grow appropriately. In the present study, a series of experiments were performed using Stigeoclonium nanum microalgal biomass to determine the removal efficiency of one of these contaminants, that is, caffeine. Experiments were performed in duplicate using 20 mL tubes. A 500 mg L-1 caffeine solution was prepared and applied at different doses at the same time as a known amount of dry biomass. The tubes were maintained at a constant temperature of 24 ± 2 °C with a stirring speed of 400 rpm. Optical absorbance readings were recorded, and calculations were performed to determine the removal percentage for each caffeine dose. At concentrations of 50, 100, and 125 mg L-1, 100% removal was reached, while at 250 and 500 mg L-1, removal was reduced to 79.76 % and 49.66%, respectively. These data indicated a continual decrease in caffeine up to 125 mg L-1, suggesting a possible saturation point for the dry biomass used over this concentration range. Furthermore, these results emphasise the necessity of conducting adsorption isotherms to understand the relationship between caffeine concentration and its removal efficiency using microalgal biomass. This could lead to the optimisation of contaminant removal, especially at higher concentrations. Although the microalgal biomass of S. nanum appears to be effective in removing caffeine at moderate concentrations, more comprehensive experiments surrounding adsorption isotherms are required to enhance efficiency at higher concentrations. [ABSTRACT FROM AUTHOR]

E-liquids contain combinations of chemicals, with many enhancing the sensory attractiveness of the product. Studies are needed to understand and characterize e-liquid ingredients, particularly flavorings, to inform future research and regulations of these products. We identified common flavor ingredients in a convenience sample of commercial e-liquids using gas chromatography–mass spectrometry. E-liquid flavors were categorized by flavor descriptors provided on the product packaging. A Flavor Ingredient Wheel was developed to link e-liquid flavor ingredients with flavor categories. An analysis of 109 samples identified 48 flavor ingredients. Consistency between the labeled flavor and ingredients used to produce such flavor was found. Our novel Flavor Ingredient Wheel organizes e-liquids by flavor and ingredients, enabling efficient analysis of the link between ingredients and their flavor profiles and allowing for quick assessment of an e-liquid ingredient's flavor profile. Investigating ingredient profiles and identifying and classifying commonly used chemicals in e-liquids may assist with future studies and improve the ability to regulate these products. [ABSTRACT FROM AUTHOR]

Background: The use of chemicals in academic laboratories is a major concern for the health and safety of individuals and the environment. Academic institutions are currently developing safe work procedures to ensure compliance with standard criteria and laboratory accreditation. However, it is unclear to what extent the activities of research laboratories... [ABSTRACT FROM AUTHOR]

Buildings with large open spaces in which chemicals are handled are often exposed to the risk of explosions. Computational fluid dynamics is a useful and convenient way to investigate contaminant dispersion in such large spaces. The turbulent Schmidt number (Sct) concept has typically been used in this regard, and most studies have adopted a default value. We studied the concentration distribution for sulfur hexafluoride (SF6) assuming different emission rates and considering the effect of Sct. Then we examined the same problem for a light gas by assuming hydrogen gas (H2) as the contaminant. When SF6 was considered as the contaminant gas, a variation in the emission rate completely changed the concentration distribution. When the emission rate was low, the gravitational effect did not take place. For both low and high emission rates, an increase in Sct accelerated the transport rate of SF6. In contrast, for H2 as the contaminant gas, a larger Sct could induce a decrease in the H2 transport rate. [ABSTRACT FROM AUTHOR]

Metrics foster trust in governing bodies, but their uncertainty can elicit an opposite sentiment of mistrust. In chemicals governance, most of the conversations concerning computational models revolve around their uncertainty, and the extent to which simulations of safe doses can be transposed in regulatory decisions. To understand the source of this mistrust in models, research in science and technology studies on policy modeling, particularly research that looks at models as an interface between science and policy, must be extended to consider the private production of predictions. Looking at the full set of actors involved in predictive regulatory knowledge – companies, regulatory agencies, modelers working with one or the other – and their concurrent articulations of uncertainty, it appears that regulators audit physiologically based pharmacokinetic models (PBPK, a key class of models used to compute safe chemical doses), because the chemical industry initially introduced them to challenge its methods of risk assessment. Regulators and their modelers established model auditing, to be able to negotiate the predictive claims of companies and their consultants. At the end of the day, neither companies nor regulators appear to dominate the production of predictive knowledge. It is the product of the shifting distribution of expertise in the regulatory space, and of the outcomes of the recurrent trials of credibility that this distribution enables. [ABSTRACT FROM AUTHOR]

Among weeds, parasitic plants have more profound effects on host plants. Due to its wide geographical distribution, high host range, and inefficient management methods, the Cuscuta (Cuscuta campestris) plant has become one of the most damaging parasites. The present study aimed to control the Cuscuta weed biologically. To this end, an experiment was conducted to investigate the allelopathic effects of the extract of the Rhazya Stricta plant on the control of this weed population in the laboratory of Velayat University of Iranshahr. The experiment was conducted as a completely randomized design with three replicates. In this experiment, negative allelopathic effects of different extracts of the R. stricta plant including acetone, aqueous, methanolic, ethanolic, and hydroalcoholic extracts on the Cuscuta were investigated in comparison with the distilled water (as control treatment). The results of this study revealed that the aqueous extract of R. stricta significantly decreased the germination percentage, germination vigor, germination rate, root length, and stem length of the Cuscuta compared to those of other treatments. Also, the other extracts of the leaves of the R. stricta plant have significant inhibitory effects on seed germination and seedling growth of the tested parasite weed species compared to those of control treatment (distilled water) suggesting the availability of inhibitory chemicals in the leaves of R. stricta to control the Cuscuta weed. It is suggested to test the negative effects of R. stricta leaf and stem extracts, after decomposition, on other weeds and adjacent and sensitive plants to R. stricta. [ABSTRACT FROM AUTHOR]

Water quality monitoring programs yield a wealth of data. It is often unclear why a certain substance occurs in higher concentrations at a certain location or time. In this study, substances were considered in clusters with co-varying concentrations rather than in isolation. A total of 196 substance clusters at 19 monitoring sites in the rivers Rhine and Meuse were identified. A total of nine clusters were found repeatedly with a similar composition at different monitoring sites. Several environmental conditions and substance properties could be linked to clusters. In addition, overlap with reference substance lists was determined. These lists group multiple substances according to emission sources, substance types, or type of use. The reference substance lists revealed that Rhine and Meuse are similarly affected. The nine 'repeating clusters' were analyzed in more detail to identify drivers. For instance, a repeating cluster with herbicides was specifically linked to high temperatures and a high number of hours in the sun per day, e.g., summer conditions. A cluster containing polychlorinated biphenyls, identified as persistent and with a high tendency to bind organic matter, was linked to high river discharge and attributed to a potential release from sediment resuspension. Not all substances could be clustered, because their concentration did not structurally vary in the same way as other substances. The presented explorative cluster analyses, along with the obtained relations with substance properties, local environmental conditions, and reference substance lists, may facilitate the reconstruction of the processes that lead to the observed variation in concentrations. This knowledge can subsequently be used by water managers to improve water quality. [ABSTRACT FROM AUTHOR]

Emerging contaminants are chemicals generated due to the usage of pesticide, endocrine disrupting compounds, pharmaceuticals, and personal care products and are liberated into the environment in trace quantities. The emerging contaminants eventually become a greater menace to living beings owing to their wide range and inhibitory action. To diminish these emerging contaminants from the environment, an Advanced Oxidation Process was considered as an efficient option. The Advanced Oxidation Process is an efficient method for mineralizing fractional or generous contaminants due to the generation of reactive species. The primary aim of this review paper is to provide a thorough knowledge on different Advanced Oxidation Process methods and to assess their mineralization efficacy of emerging contaminants. This study indicates the need for an integrated process for enhancing the treatment efficiency and overcoming the drawbacks of the individual Advanced Oxidation Process. Further, its application concerning technical and economic aspects is reviewed. Until now, most of the studies have been based on lab or pilot scale and do not represent the actual scenario of the emerging contaminant mineralization. Thus, the scaling up of the process was discussed, and the major challenges in large scale implementation were pointed out. [Display omitted] • Emerging contaminants in very trace quantity affects the aquatic living organisms. • Hydroxyl radicals generated from advanced oxidation process mineralize contaminants. • Generation of intermediates during oxidation process is also a major challenge. • The mineralization of advanced oxidation process is effective at 3–3.5 pH. • Almost 100% degradation of contaminants were achieved by optimizing parameters. [ABSTRACT FROM AUTHOR]

Organic pollutants are potential hazards for human health and are pivotal contributors to ecological imbalances. The spectrum of chemicals in research on organic pollutants has continually evolved, which is influenced by industrial advancements, scientific breakthroughs, and regulatory frameworks. A comprehensive analysis of 30 review articles on organic pollutants published during 2019-2023 in Critical Reviews in Environmental Science and Technology (CREST) provides good perspectives on the trajectory of organic pollutants in the environment. This synthesis delineates the recent advancements in two domains: (1) innovative monitoring technologies (sensor, extraction method, bio-indicator, and radioactive tracer); and (2) fate and transport, and risk assessment of organic pollutants. However, research on organic pollutants needs better monitoring techniques, matrix-related transformation methodologies, and realistic risk assessment tools. The development of novel strategies to monitor and manage organic pollutants, coupled with evaluations of ecosystem impacts under field conditions, is paramount. [ABSTRACT FROM AUTHOR]

Copyright of Artvin Çoruh Üniversitesi Orman Fakültesi Dergisi is the property of Artvin Coruh University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)