Artykuły w czasopismach: „Chlorine attenuation”

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Naqvi, A. A., M. Maslehuddin, Khateeb ur-Rehman i O. S. B. Al-Amoudi. "Chlorine signal attenuation in concrete". Applied Radiation and Isotopes 105 (listopad 2015): 6–10. http://dx.doi.org/10.1016/j.apradiso.2015.07.010.

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Coleman, Max L., Magali Ader, Swades Chaudhuri i John D. Coates. "Microbial Isotopic Fractionation of Perchlorate Chlorine". Applied and Environmental Microbiology 69, nr 8 (sierpień 2003): 4997–5000. http://dx.doi.org/10.1128/aem.69.8.4997-5000.2003.

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ABSTRACT Perchlorate contamination can be microbially respired to innocuous chloride and thus can be treated effectively. However, monitoring a bioremediative strategy is often difficult due to the complexities of environmental samples. Here we demonstrate that microbial respiration of perchlorate results in a significant fractionation (∼−15‰) of the chlorine stable isotope composition of perchlorate. This can be used to quantify the extent of biotic degradation and to separate biotic from abiotic attenuation of this contaminant.

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Aldhafiri, Sarah, Huda Mahmoud, Mohammed Al-Sarawi i Wael A. Ismail. "Natural Attenuation Potential of Polychlorinated Biphenyl-Polluted Marine Sediments". Polish Journal of Microbiology 67, nr 1 (9.03.2018): 37–48. http://dx.doi.org/10.5604/01.3001.0011.6140.

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The marine environment in Kuwait is polluted with various hazardous chemicals of industrial origin. These include petroleum hydrocarbons, halogenated compounds and heavy metals. Bioremediation with dedicated microorganisms can be effectively applied for reclamation of the polluted marine sediments. However, information on the autochthonous microbes and their ecophysiology is largely lacking. We analyzed sediments from Shuwaikh harbor to detect polychlorinated biphenyls (PCBs) and total petroleum hydrocarbons (TPHs). Then we adopted both culture-dependent and culture-independent (PCR-DGGE) approaches to identify bacterial inhabitants of the polluted marine sediments from Shuwaikh harbor. The chemical analysis revealed spatial variation among the sampling stations in terms of total amount of PCBs, TPHs and the PCB congener fingerprints. Moreover, in all analyzed sediments, the medium-chlorine PCB congeners were more abundant than the low-chlorine and high-chlorine counterparts. PCR-DGGE showed the presence of members of the Proteobacteria, Spirochaetes, Firmicutes and Bacteroidetes in the analyzed sediments. However, Chloroflexi-related bacteria dominated the detected bacterial community. We also enriched a biphenyl-utilizing mixed culture using the W2 station sediment as an inoculum in chemically defined medium using biphenyl as a sole carbon and energy source. The enriched mixed culture consisted mainly of the Firmicute Paenibacillus spp. Sequences of genes encoding putative aromatic ring-hydroxylating dioxygenases were detected in sediments from most sampling stations and the enriched mixed culture. The results suggest the potential of bioremediation as a means for natural attenuation of Shuwaikh harbor sediments polluted with PCBs and TPHs.

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Zhou, Jing Hai, Yu Xian Zhang, Xian Hong Meng i Ying Liu. "Research on Residual Strength of Concrete under Fatigue Loading and Corrosion of Chloride". Applied Mechanics and Materials 94-96 (wrzesień 2011): 1369–72. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.1369.

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In the actual project, many concrete structures not only suffer the loading of static force and the repeated loading but also affected by the corrosive effects of chemical substances in external environment, which makes concrete corrosion and damage become an unavoidable issue in engineering. The research on it at home and abroad is still in stage of theoretical exploration. This paper studied the attenuation of the residual strength of concrete under fatigue loading and corrosion of chloride, using self-designed experimental corrosion fatigue loading device. The results show that the corrosion of concrete by chlorine ion is unneglected, its influence is greater than mathematical superposition of alternating load and corrosion when they affect the concrete separately.

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Sturchio, N. C., J. L. Clausen, L. J. Heraty, L. Huang, B. D. Holt i T. A. Abrajano. "Chlorine Isotope Investigation of Natural Attenuation of Trichloroethene in an Aerobic Aquifer". Environmental Science & Technology 32, nr 20 (październik 1998): 3037–42. http://dx.doi.org/10.1021/es9802605.

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Liu, Zhi, Yi-Li Lin, Tian-Yang Zhang, Chen-Yan Hu, Zheng-Xiong Zheng, Yu-Lin Tang, Tong-Cheng Cao, Bin Xu i Nai-Yun Gao. "Enhanced formation of iodinated trihalomethanes in a mixed chlorine/chloramine system and attenuation by UV-activated process". Journal of Hazardous Materials 429 (maj 2022): 128370. http://dx.doi.org/10.1016/j.jhazmat.2022.128370.

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Böhm, Stanislav, i Otto Exner. "Attenuation of the Substituent Effects Along the Aliphatic Chain". Collection of Czechoslovak Chemical Communications 69, nr 5 (2004): 984–95. http://dx.doi.org/10.1135/cccc20040984.

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Two series of model compounds were devised to follow the attenuation of substituent effects with an interposed methylene group: short-chain aliphatic compounds 1 and derivatives of bicyclo[2.2.2]octane 5. In all compounds, chlorine atom acts as substituent and charged oxygen atom as the functional group; the interaction of both is measured by the reaction energy of the isodesmic reaction calculated at the B3LYP/AUG-cc-pVTZ//B3LYP/6-311+G(d,p) and/or B3LYP/6-311+G(d,p) levels. Attenuation of the substituent inductive effect with the distance is less steep than observed previously in solution. It depends also markedly on the conformation but cannot be reproduced, not even approximately, by the electrostatic formula. Only for simple regular conformations, it can be described approximately by an exponential function with the transmission factor for one methylene group equal to 0.74. The behavior of isolated molecules differs in this case distinctly from the reactivity in solution. Nevertheless, the significance of the two formulas, electrostatic and exponential, is similar in the isolated molecules and in solution. These formulas represent only two different, rather crude mathematical approximations and cannot be given any physical meaning.

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Pinto, Andréia Adelaide Gordinho, Mirian Y. Oliveira Nagai, Ednar Nascimento Coimbra, Suham Nowrooz Mohammad, Jefferson Souza Silva, Adalberto Von Ancken, Sandra Augusta Gordinho Pinto i in. "Mercury chloride toxicity attenuation of the Brine Shrimp Artemia Salina after treatment with Mercurius corrosivus as isotherapic". International Journal of High Dilution Research - ISSN 1982-6206 21, nr 2 (26.09.2022): 06. http://dx.doi.org/10.51910/ijhdr.v21i2.1211.

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Isotherapics prepared from toxic substances have been described as attenuation factors for heavy metal intoxication in aquatic animals. Herein, Artemia salina and mercury chloride were used as a model to identify treatment-related bioresilience. The aim was to describe the effects of Mercurius corrosivus (MC) in different potencies on Artemia salina cyst hatching and on mercury bioavailability. Artemia salina cysts were exposed to 5.0 µg/mL of mercury chloride during the hatching phase. MC 6cH, 30cH, and 200cH were prepared and poured into artificial seawater. Different controls were used (nonchallenged cysts and challenged cysts treated with water, succussed water, and Ethilicum 1cH). Four series of nine experiments were performed for 4 weeks to evaluate the percentage of cyst hatching considering all moon phases. Soluble total mercury (THg) levels and precipitated mercury content were also evaluated. Solvatochromic dyes were used to check for eventual physicochemical markers of MC biological activity. Two-way analysis of variance (ANOVA) with mixed models was used for evaluating the effect of different treatments and the simultaneous influence of the moon phases on the cysts hatching rate, at both observation times (24 and 48 hours). When necessary, outliers were removed, using the Tukey criterion. The level of significance α was set at 5%. Significant delay (p<0.0001) in cyst hatching was observed after treatment with MC 30cH, compared with the controls. An increase in THg concentration in seawater (p<0.0018) and of chlorine/oxygen ratio (p<0.0001) in suspended micro-aggregates was also seen, with possible relation with mercury bioavailability. Specific interaction of MC 30cH with the solvatochromic dye ET33 (p<0.0017) was found. The other observed potencies of Mercurius corrosivus 6 and 200 cH were not significant in relation to the observed groups. The results were postulated as being protective effects of MC 30cH on Artemia salina, by improving its bioresilience.

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Hu, Ruigan, Fuyue Liu, Haoqi Qiu, He Miao, Qin Wang, Houcheng Zhang, Fu Wang i Jinliang Yuan. "High-Property Anode Catalyst Compositing Co-Based Perovskite and NiFe-Layered Double Hydroxide for Alkaline Seawater Splitting". Processes 10, nr 4 (29.03.2022): 668. http://dx.doi.org/10.3390/pr10040668.

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The progress of high-efficiency non-precious metal anode catalysts for direct seawater splitting is of great importance. However, due to the slow oxygen evolution reaction (OER) kinetics, competition of chlorine evolution reaction (ClER), and corrosion of chloride ions on the anode, the direct seawater splitting faces many challenges. Herein, we develop a perovskite@NiFe layered double hydroxide composite for anode catalyst based on Ba0.5Sr0.5Co0.8Fe0.2O3 (BSCF) and NiFe layered double hydroxide (NiFe-LDH) heterostructure. The optimized BSCF@CeO2@NiFe exhibits excellent OER activity, with the potential at 100 mA cm−2 (Ej = 100) being 1.62 V in the alkaline natural seawater. Moreover, the electrolytic cell composed of BSCF@CeO2@NiFe anode shows an excellent stability, with negligible attenuation during the long-term overall seawater splitting with the remarkable self-recovery ability in the initial operation stage, and the direct seawater splitting potential increasing by about 30 mV at 10 mA cm−2. Our work can give a guidance for the design and preparation of anode catalysts for the direct seawater splitting.

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Brezhnev, Nikolay Yu, Andrey V. Kosyakov, Anastasia V. Steich i Alexander Yu Zavrazhnov. "High-temperature spectrophotometry of indium chloride vapours as a method of study of the In – Se system". Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases 23, nr 4 (24.11.2021): 482–95. http://dx.doi.org/10.17308/kcmf.2021.23/3667.

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The goals of this work are as follows: (а) searching for a method of study of the In – Se system taking into account the specified problems and difficulties, (b) choosing a way for the instrumental implementation of this method, and (c) obtaining experimental evidence that this method and its implementation are promising. The choice of the In – Se system is related to the fact that indium selenides, layered structures and semiconductor phases with stoichiometric vacancies, are promising from the point of view of materials science. This choice is also related to the use of binary precursors for the synthesis of heterostructures based on CIS compounds.We studied the possibility of applying the auxiliary component method using the equilibrium with the participation of indium chloride vapours which were made to contact the condensed phases of the In – Se system. Equilibrium was achieved using high-temperature spectrophotometry of the vapour phase. The experiment had two stages. During the first stage we determined the absorption characteristics of the InCl3 vapour. During the second stage we studied the heterogeneous equilibrium of the unsaturated indium chloride vapour with several phases of the In – Se system. Over the course of the study, we determined the molar attenuation coefficients of the InCl3 vapour and plotted the temperature dependences of the value KP.It was found that the phase composition of the alloys significantly influences the position of the corresponding lines on the KP–T diagram, which proves the possibility of using the suggested auxiliary component method in its specific instrumental (spectrophotometric) implementation in order to study the In – Se system. We also showed the additional possibilities of using this method for plotting T-x diagrams of binary systems in such high-temperature areas where the binary solid phase is in equilibrium with the melt. This application of the method is related to the solubility of a vapour of an auxiliary component (chlorine in the form of indium chlorides) in the melts of binary phases (indium selenides).

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Sturchio, Neil C., John Karl Böhlke, Abelardo D. Beloso,, Sheryl H. Streger, Linnea J. Heraty i Paul B. Hatzinger. "Oxygen and Chlorine Isotopic Fractionation during Perchlorate Biodegradation: Laboratory Results and Implications for Forensics and Natural Attenuation Studies". Environmental Science & Technology 41, nr 8 (kwiecień 2007): 2796–802. http://dx.doi.org/10.1021/es0621849.

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Tatarinov D. A., Sokolova A. V., Danilov D. V. i Litvin A. P. "Change of optical properties of inorganic perovskite nanocrystals of CsPbCl-=SUB=-x-=/SUB=-Br-=SUB=-3-x-=/SUB=-, alloyed with Yb-=SUP=-3+-=/SUP=- ions, when carrying out an anion exchange reaction". Optics and Spectroscopy 130, nr 8 (2022): 1034. http://dx.doi.org/10.21883/eos.2022.08.54778.2772-22.

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Alloying of perovskites nanocrystals by lanthanoids makes it possible to produce materials that luminesce effectively in both visible and near infrared spectra. In the present work, the influence of the width of the forbidden zone on the optical properties of the inorganic perovskites nanocrystals CsPbClxBr3-x alloyed by ions Yb3+ is investigated. For changing the chemical composition of nanocrystals, an anionic exchange method is used by adding bromide dodecyltrimethylammonium. As a result of the gradual substitution of chlorine ions with bromine ions, the forbidden area of nanocrystals is narrowed, resulting in a change in the spectral position of the optical transitions, the quantum output of photoluminescence in the near and infrared spectral ranges and the attenuation of photoluminescence. When the width of the forbidden area reaches 2.54 eV, the total quantum output of photoluminescence reaches 72%. Keywords: pervoskite nanocrystals, alloying, ytterbium, photoluminescence, anionic exchange.

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Teipel, Jan, Vera Gottstein, Eva Hölzle, Katja Kaltenbach, Dirk W. Lachenmeier i Thomas Kuballa. "An Easy and Reliable Method for the Mitigation of Deuterated Chloroform Decomposition to Stabilise Susceptible NMR Samples". Chemistry 4, nr 3 (2.08.2022): 776–85. http://dx.doi.org/10.3390/chemistry4030055.

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Highly reactive decomposition products of deuterated chloroform can deteriorate samples dissolved in this commonly used solvent for nuclear magnetic resonance (NMR) spectroscopy. Samples for metabolomics studies often contain a complex mixture of sensitive substances such as phospholipids, peptides, unsaturated fatty acids or vitamins. If these react with decomposition products (of chloroform), abnormal NMR spectra could result, e.g., signal shifts depending on pH, attenuation of signals over time due to chemical changes of analytes or new signals from reaction products. Such irreproducibly influenced spectra are especially problematic for non-targeted analysis methods using automated chemometrical data evaluation. To prevent these artefacts, chlorine, phosgene and hydrochloric acid need to be eliminated from deuterated chloroform before its use. Since the common stabilisation methods have proven to be insufficient for sensitive NMR samples, another purging method has been tested: Mitigation is easily and reliably achieved by washing the deuterated chloroform with concentrated disodium carbonate solution and subsequent desiccation with oven-dried disodium carbonate.

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Zhang, Yingna, Feng Dou, Yijia Zhou, Xiaofeng Zhao, Jiangshan Chen, Cheng Wang i Shuhong Wang. "Ternary Electrical Memory Devices Based on Polycarbazole: SnO2 Nanoparticles Composite Material". Polymers 14, nr 7 (6.04.2022): 1494. http://dx.doi.org/10.3390/polym14071494.

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In this paper, a D–A polymer (PIB) containing carbazole as the donor group in the main chain and benzimidazole benzisoindolinone as the acceptor group was synthesized by Suzuki reaction. The Suzuki reaction, also known as the Suzuki coupling reaction, is a relatively new organic coupling reaction in which aryl or alkenyl boronic acids or boronic acid esters react with chlorine, bromine, iodoaromatic hydrocarbons or alkenes under the catalysis of zerovalent palladium complexes cross-coupling. A series of devices were fabricated by a spin-coating approach, and the devices all exhibited ternary resistance switching storage behavior. Among them, the composite device with the mass fraction of SnO2 NPs of 5 wt% has the best storage performance, with a threshold voltage of −0.4 V and a switching current ratio of 1:101.5:104.5. At the same time, the current of the device remained stable after a 3-h test. Furthermore, after 103 cycles, the current has no obvious attenuation. The device has good stability and continuity. Moreover, the conduction mechanism is further revealed. Inorganic nanoparticle composite devices have splendid memory performances and exhibit underlying application significance in storing data.

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Minnich, Michael G., i R. S. Houk. "Comparison of cryogenic and membrane desolvation for attenuation of oxide, hydride and hydroxide ions and ions containing chlorine in inductively coupled plasma mass spectrometry". Journal of Analytical Atomic Spectrometry 13, nr 3 (1998): 167–74. http://dx.doi.org/10.1039/a704274d.

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Braddock, Isabel H. B., Maya Al Sid Cheikh, Joydip Ghosh, Roma E. Mulholland, Joseph G. O’Neill, Vlad Stolojan, Carol Crean, Stephen J. Sweeney i Paul J. Sellin. "Formamidinium Lead Halide Perovskite Nanocomposite Scintillators". Nanomaterials 12, nr 13 (22.06.2022): 2141. http://dx.doi.org/10.3390/nano12132141.

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While there is great demand for effective, affordable radiation detectors in various applications, many commonly used scintillators have major drawbacks. Conventional inorganic scintillators have a fixed emission wavelength and require expensive, high-temperature synthesis; plastic scintillators, while fast, inexpensive, and robust, have low atomic numbers, limiting their X-ray stopping power. Formamidinium lead halide perovskite nanocrystals show promise as scintillators due to their high X-ray attenuation coefficient and bright luminescence. Here, we used a room-temperature, solution-growth method to produce mixed-halide FAPbX3 (X = Cl, Br) nanocrystals with emission wavelengths that can be varied between 403 and 531 nm via adjustments to the halide ratio. The substitution of bromine for increasing amounts of chlorine resulted in violet emission with faster lifetimes, while larger proportions of bromine resulted in green emission with increased luminescence intensity. By loading FAPbBr3 nanocrystals into a PVT-based plastic scintillator matrix, we produced 1 mm-thick nanocomposite scintillators, which have brighter luminescence than the PVT-based plastic scintillator alone. While nanocomposites such as these are often opaque due to optical scattering from aggregates of the nanoparticles, we used a surface modification technique to improve transmission through the composites. A composite of FAPbBr3 nanocrystals encapsulated in inert PMMA produced even stronger luminescence, with intensity 3.8× greater than a comparative FAPbBr3/plastic scintillator composite. However, the luminescence decay time of the FAPbBr3/PMMA composite was more than 3× slower than that of the FAPbBr3/plastic scintillator composite. We also demonstrate the potential of these lead halide perovskite nanocomposite scintillators for low-cost X-ray imaging applications.

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Idiri, Z., F. Redjem i N. Beloudah. "Analysis of sewage sludge using an experimental prompt gamma neutron activation analysis (pgnaa) set-up with an am-be source". International Journal of Modern Physics: Conference Series 44 (styczeń 2016): 1660215. http://dx.doi.org/10.1142/s2010194516602155.

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An experimental PGNAA set-up using a 1 Ci Am–Be source has been developed and used for analysis of bulk sewage sludge samples issued from a wastewater treatment plant situated in an industrial area of Algiers. The sample dimensions were optimized using thermal neutron flux calculations carried out with the MCNP5 Monte Carlo Code. A methodology is then proposed to perform quantitative analysis using the absolute method. For this, average thermal neutron flux inside the sludge samples is deduced using average thermal neutron flux in reference water samples and thermal flux measurements with the aid of a 3He neutron detector. The average absolute gamma detection efficiency is determined using the prompt gammas emitted by chlorine dissolved in a water sample. The gamma detection efficiency is normalized for sludge samples using gamma attenuation factors calculated with the MCNP5 code for water and sludge. Wet and dehydrated sludge samples were analyzed. Nutritive elements (Ca, N, P, K) and heavy metals elements like Cr and Mn were determined. For some elements, the PGNAA values were compared to those obtained using Atomic Absorption Spectroscopy (AAS) and Inductively Coupled Plasma (ICP) methods. Good agreement is observed between the different values. Heavy element concentrations are very high compared to normal values; this is related to the fact that the wastewater treatment plant is treating not only domestic but also industrial wastewater that is probably rejected by industries without removal of pollutant elements. The detection limits for almost all elements of interest are sufficiently low for the method to be well suited for such analysis.

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MOISIUK, Oleksandr, i Andrii SAMILA. "INVESTIGATION ABOUT ELECTROMAGNETIC FIELD TOPOLOGY OF THE SPIRAL COIL FOR NQR DETECTOR OF EXPLOSIVE AND NARCOTIC SUBSTANCES". HERALD OF KHMELNYTSKYI NATIONAL UNIVERSITY 299, nr 4 (październik 2021): 101–7. http://dx.doi.org/10.31891/2307-5732-2021-299-4-101-107.

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Given the increased likelihood of dangerous situations in Ukraine and abroad related to the intensification and scale of terrorist acts, it is important not only to quickly locate and eliminate the terrible consequences, but also to prevent, including prevent destabilizing factors. That is why remote detection of explosives and drugs is relevant and promising in the direction of strengthening the fight against terrorism and increasing national security. A promising method for detecting the vast majority of explosives and narcotics that contain nitrogen (14N) or chlorine atoms (35Cl, 37Cl) is the nuclear quadrupole resonance method. In the presence of a gradient of high-frequency field strength inside the sample in the process of forming the response signal is “blurring” the vector of the total spin magnetization, which leads to the expansion of the resonant signal and reduce its amplitude. Increasing the homogeneity of the high-frequency field is especially important for the detection of weak signals observed in the study of substances with a low natural prevalence of magnetoactive nuclei. The paper presents the results of research on the topology of the electromagnetic field strength of a helical coil designed for use as a transmitting and receiving antenna of a portable detector of explosives and drugs, the principle of which is based on the registration of 14N isotope signals by nuclear quadrupole resonance. To determine the topology of the electromagnetic field, a computational domain was created, which is a model of the physical structure of the spiral coil. The finite element method performed numerical simulations in COMSOL Multiphysics. The simulation was performed at a frequency of 3.4 MHz, which is close to the value of the detection frequency of the attenuation signal of free induction from sodium nitrite 3.41 MHz. The best results were shown by the model of the coil with five turns, internal radius of 25 mm, external radius of 225 mm. The obtained magnetic field diagrams indicate better resistance to radio frequency interference when working in a real experiment. Based on the data obtained during the simulation, a multilayer (Multislice) model of the electric field and the isosurface of the electromagnetic field of the studied model were created, which demonstrate the dynamics and density of the electromagnetic field around the coil. From the obtained graphical dependences it is possible to draw a conclusion about the normalized attenuation of the intensity of electric field radiation from the geometric center of the coil, which, in turn, makes it clear exactly how to place the sample.

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Bender, Kelly S., Melissa R. Rice, William H. Fugate, John D. Coates i Laurie A. Achenbach. "Metabolic Primers for Detection of (Per)chlorate-Reducing Bacteria in the Environment and Phylogenetic Analysis of cld Gene Sequences". Applied and Environmental Microbiology 70, nr 9 (wrzesień 2004): 5651–58. http://dx.doi.org/10.1128/aem.70.9.5651-5658.2004.

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ABSTRACT Natural attenuation of the environmental contaminant perchlorate is a cost-effective alternative to current removal methods. The success of natural perchlorate remediation is dependent on the presence and activity of dissimilatory (per)chlorate-reducing bacteria (DPRB) within a target site. To detect DPRB in the environment, two degenerate primer sets targeting the chlorite dismutase (cld) gene were developed and optimized. A nested PCR approach was used in conjunction with these primer sets to increase the sensitivity of the molecular detection method. Screening of environmental samples indicated that all products amplified by this method were cld gene sequences. These sequences were obtained from pristine sites as well as contaminated sites from which DPRB were isolated. More than one cld phylotype was also identified from some samples, indicating the presence of more than one DPRB strain at those sites. The use of these primer sets represents a direct and sensitive molecular method for the qualitative detection of (per)chlorate-reducing bacteria in the environment, thus offering another tool for monitoring natural attenuation. Sequences of cld genes isolated in the course of this project were also generated from various DPRB and provided the first opportunity for a phylogenetic treatment of this metabolic gene. Comparisons of the cld and 16S ribosomal DNA (rDNA) gene trees indicated that the cld gene does not track 16S rDNA phylogeny, further implicating the possible role of horizontal transfer in the evolution of (per)chlorate respiration.

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Qin, Ming Qiang, Wen Zhan, Wen Bing Xu i Jin Hui Li. "Effect of Stone Powder Content on the Diffusing Parameter and Diffusion Attenuation Coefficient of Chloride Ion of Mechanical Sand Concrete". Applied Mechanics and Materials 584-586 (lipiec 2014): 1818–22. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.1818.

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The effect of stone powder content on the chloride diffusion coefficient and diffusion attenuation coefficient of chloride ion of mechanical sand (MS) concrete was studied. The results showed that the resistance to chloride ion permeability of MS concrete firstly increased and then decreased with the increase of the content of stone powder. The anti-permeability of the concrete which had moderate amount of stone powder was better than that of the natural river sand (NS) concrete. The diffusion attenuation coefficient of MS concrete was greater than that of the NS concrete, which was good for long-term durability of concrete structure.

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Ruhlmann, J., A. Hotze, H. J. Biersack i A. Bockisch. "Beeinflussung der 201TI-SPECT des Myokards durch die Mamma-Absorption". Nuklearmedizin 28, nr 04 (1989): 145–47. http://dx.doi.org/10.1055/s-0038-1629486.

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The attenuation effect of the female breast on single-photon emission computed 201TI-chloride myocardial tomograms (SPECT) was quantitatively evaluated in a group of 20 women. SPECT was carried out with the left breast in the normal position and after its maximal upward displacement. The count rate gain was up to 30% when the breast was raised. 201TI-chloride myocardial SPECT often showed false lesions in the anterior wall which resulted from the attenuation of the gamma rays by the female breast. This factor is neglected in constructing the tomograms, and even if such artifacts are absent, the attenuation may adversely affect the calculated wash-out values.

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Mizzen, Lee, Anne Hilton, Steve Cheley i Robert Anderson. "Attenuation of murine coronavirus infection by ammonium chloride". Virology 142, nr 2 (kwiecień 1985): 378–88. http://dx.doi.org/10.1016/0042-6822(85)90345-9.

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Sato, T., i Y. Okamoto. "Density of Molten Terbium Chloride". Zeitschrift für Naturforschung A 58, nr 2-3 (1.03.2003): 183–85. http://dx.doi.org/10.1515/zna-2003-2-317.

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The density of molten terbium chloride at 993 to 1213 K, as measured by the γ -ray attenuation method, is found to be d = [3.937±0.028−(4.76±0.25) · 10−4T] g/cm3. The characteristic state parameters of molten TbCl3 are found to be 1129 K and 78.0 ml for T* and ν*, respectively.

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DiFranco, Marino, Alvaro Herrera i Julio L. Vergara. "Chloride currents from the transverse tubular system in adult mammalian skeletal muscle fibers". Journal of General Physiology 137, nr 1 (13.12.2010): 21–41. http://dx.doi.org/10.1085/jgp.201010496.

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Chloride fluxes are the main contributors to the resting conductance of mammalian skeletal muscle fibers. ClC-1, the most abundant chloride channel isoform in this preparation, is believed to be responsible for this conductance. However, the actual distribution of ClC-1 channels between the surface and transverse tubular system (TTS) membranes has not been assessed in intact muscle fibers. To investigate this issue, we voltageclamped enzymatically dissociated short fibers using a two-microelectrode configuration and simultaneously recorded chloride currents (ICl) and di-8-ANEPPS fluorescence signals to assess membrane potential changes in the TTS. Experiments were conducted in conditions that blocked all but the chloride conductance. Fibers were equilibrated with 40 or 70 mM intracellular chloride to enhance the magnitude of inward ICl, and the specific ClC-1 blocker 9-ACA was used to eliminate these currents whenever necessary. Voltage-dependent di-8-ANEPPS signals and ICl acquired before (control) and after the addition of 9-ACA were comparatively assessed. Early after the onset of stimulus pulses, di-8-ANEPPS signals under control conditions were smaller than those recorded in the presence of 9-ACA. We defined as attenuation the normalized time-dependent difference between these signals. Attenuation was discovered to be ICl dependent since its magnitude varied in close correlation with the amplitude and time course of ICl. While the properties of ICl, and those of the attenuation seen in optical records, could be simultaneously predicted by model simulations when the chloride permeability (PCl) at the surface and TTS membranes were approximately equal, the model failed to explain the optical data if PCl was precluded from the TTS membranes. Since the ratio between the areas of TTS membranes and the sarcolemma is large in mammalian muscle fibers, our results demonstrate that a significant fraction of the experimentally recorded ICl arises from TTS contributions.

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Venkatesan, G., i G. Swaminathan. "REVIEW OF CHLORIDE AND SULPHATE ATTENUATION IN GROUND WATER NEARBY SOLID‐WASTE LANDFILL SITES/CHLORIDŲ IR SULFATŲ MAŽINIMO POŽEMINIAME VANDENYJE ŠALIA SĄVARTYNŲ PROBLEMOS/УМЕНЬШЕНИE ХЛОРИДОВ И СУЛЬФАТОВ В ПОДЗЕМНЫХ ВОДАХ ВБЛИЗИ СВАЛОК". JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 17, nr 1 (31.03.2009): 1–7. http://dx.doi.org/10.3846/1648-6897.2009.17.ia-ig.

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D'Ambrosio, Daniela, Federico Zagni, Antonello E. Spinelli i Mario Marengo. "Attenuation Correction for Small Animal PET Images: A Comparison of Two Methods". Computational and Mathematical Methods in Medicine 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/103476.

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In order to extract quantitative parameters from PET images, several physical effects such as photon attenuation, scatter, and partial volume must be taken into account. The main objectives of this work were the evaluation of photon attenuation in small animals and the implementation of two attenuation correction methods based on X-rays CT and segmentation of emission images. The accuracy of the first method with respect to the beam hardening effect was investigated by using Monte Carlo simulations. Mouse- and rat-sized phantoms were acquired in order to evaluate attenuation correction in terms of counts increment and recovery of uniform activity concentration. Both methods were applied to mice and rat images acquired with several radiotracers such asF18-FDG,11C-acetate,68Ga-chloride, andF18-NaF. The accuracy of the proposed methods was evaluated in heart and tumour tissues usingF18-FDG images and in liver, kidney, and spinal column tissues usingC11-acetate,Ga68-chloride, andF18-NaF images, respectively.In vivoresults from animal studies show that, except for bone scans, differences between the proposed methods were about 10% in rats and 3% in mice. In conclusion, both methods provide equivalent results; however, the segmentation-based approach has several advantages being less time consuming and simple to implement.

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Zhou, Xiangong, Xiaoyu Zhang, Gang Li i Jialu Li. "Carbonation Characteristics and Bearing Capacity Attenuation of Loaded RC Beam Coupled with Chloride Erosion". Advances in Civil Engineering 2022 (15.07.2022): 1–15. http://dx.doi.org/10.1155/2022/5365789.

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The durability of a concrete bridge structure is a systematic problem composed of material, structure, natural environment, and service environment. Various factors are coupled, which affect each other, and single-factor research cannot fundamentally solve this problem. In this paper, the carbonation characteristics of RC beams with different loading states under the coupling action of carbonation and chloride erosion are studied. Through the experiment, the author tries to find the influence of stress state and chloride ion erosion on the carbonation of concrete and analyze the failure mode and the attenuation rules of the flexural and shearing capacity of the corroded RC beams under the coupling action. For this purpose, five groups of experiments under different working conditions were designed, including chloride ion erosion and carbonation experiments without external load of the cubic blocks, and chloride erosion and carbonation coupling experiments of RC beams under different stress states and stress levels. The carbonation rate of concrete can be reduced by 56%∼60% under the coupling action of chloride salt. Different loading states and stress levels have an obvious influence on carbonation and chloride ion corrosion, which further affects the corrosion rate of steel bars. Under a low corrosion rate, the bending and shear failure modes of the corroded beams are similar to those of the noncorroded beams, and the section strain distribution still approximately conforms to the plane section assumption. The relationship between the relative ultimate shear strength or the relative ultimate flexural strength and the average section-corrosion rate of the reinforcement is approximately linear.

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Chen, Zheng, Xi Bin Zhao, Yan Hua Yuan, Zhong Hua Wang, Lu Feng Yang i Qiong Ming Jiang. "On the Time Dependency of the Chloride Diffusion in High Performance Concrete". Advanced Materials Research 721 (lipiec 2013): 148–52. http://dx.doi.org/10.4028/www.scientific.net/amr.721.148.

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The chloride diffusion coefficient of concrete is time dependent. The high performance concrete (HPC) was prepared and the specimens were tested by ASTM C1202 and the durability of HPC in long period is analyzed with the time dependency of diffusion in this paper. The results show that the chloride diffusion coefficients of the HPC with only fly ash are large than those of the HPC with multi-admixtures, but the attenuation of the chloride diffusion coefficients of the formers are faster than the latters. The analysis results show that the chloride concentrations in concrete is over estimated when time-dependence of chloride diffusion is not considered, and the durability of concrete in long period is determined by both chloride diffusion coefficient and age factor.

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Nikeghbal, Kiana, Zahra Zamanian, Shoaleh Shahidi, Gianrico Spagnuolo i Parisa Soltani. "Designing and Fabricating Nano-Structured and Micro-Structured Radiation Shields for Protection against CBCT Exposure". Materials 13, nr 19 (30.09.2020): 4371. http://dx.doi.org/10.3390/ma13194371.

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Researchers have always been interested in finding new and effective materials for protection against radiation. This experimental study aimed to design and fabricate new types of nano-material and micro-material based shields against the ionizing effect of cone beam computed tomography (CBCT) X-rays. To fabricate a flexible prototype, we added dioctyl phthalate (DOP) oil to emulsion polyvinyl chloride (PVC) powder. The paste was mixed and dispersed. Then, nano- and micro-powders of WO3 and Bi2O3 were added to the paste, with the weight ratio of 20% PVC, 20% DOP, and 60% nano- and micro-metals. Using an ultrasonic mixer, the polymer matrix and metals were mixed and a paste with a thick texture was developed. The resultant paste was poured into glass molds and the molds were then heated in an oven. After cooling, the resultant sheets were selected for further experiments. A CBCT unit and dosimeter were used to evaluate the characterization and X-ray shielding properties of the fabricated prototypes. The half-value layers (HVL) for nano-WO3, micro-WO3, nano-Bi2O3, and micro-Bi2O3 were 0.0390, 0.0524, 0.0351, and 0.0374 cm, respectively. In addition, the linear attenuation coefficient (µ) for these materials were 17.77, 13.20, 19.71, and 18.5 cm−1, respectively. The findings indicate that nano-structured samples are more effective in the attenuation of X-ray energy. The nano-structured WO3 prototype was nearly 34% more efficient in attenuating radiation compared to the micro-structured WO3 prototype. This difference in nano- and micro-structured Bi2O3 prototypes was 6.5%.

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Igisheva, AL, EG Soboleva i TB Krit. "Low-frequency ultrasound attenuation in sodium chlorate crystals". Journal of Physics: Conference Series 769 (listopad 2016): 012061. http://dx.doi.org/10.1088/1742-6596/769/1/012061.

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Takenaka, T., M. Epstein, H. Forster, D. W. Landry, K. Iijima i M. S. Goligorsky. "Attenuation of endothelin effects by a chloride channel inhibitor, indanyloxyacetic acid". American Journal of Physiology-Renal Physiology 262, nr 5 (1.05.1992): F799—F806. http://dx.doi.org/10.1152/ajprenal.1992.262.5.f799.

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We have recently proposed that the actions of endothelin (ET) are in part mediated by opening of chloride channels (K. Iijima, L. Lin, A. Nasjletti, and M. S. Goligorsky. Am. J. Physiol. 260 (Cell Physiol. 29: C982-C992, 1991). In the present study the ability of a chloride channel inhibitor, an indanyloxyacetic acid (IAA-94), to block ET-induced effects was examined in cultured vascular smooth muscle cells (VSMC) by spectrofluorometry and direct videomicroscopic visualization of the renal microcirculation in isolated perfused hydronephrotic kidneys (IPHK). A fluorescein isothiocyanate (FITC)-labeled IAA-94 analogue showed specific binding to VSMC. IAA-94 (30 microM) neither affected basal cytosolic calcium concentration ([Ca2+]i) in VSMC nor peak response to ET, but it significantly curtailed sustained elevation of [Ca2+]i (half-time recovery was 147 +/- 23 vs. 248 +/- 33 s in control, P less than 0.05). IAA-94 blunted ET-induced membrane depolarization from 24.5 +/- 3.3 to 8.0 +/- 1.8 mV. In IPHK, ET constricted afferent arterioles (AA) by 29 +/- 2% (18.7 +/- 0.8 to 13.2 +/- 0.6 microns, P less than 0.001). Isradipine reversed this ET-induced vasoconstriction. Pretreatment with IAA-94 did not alter AA diameter, but markedly attenuated ET-induced AA constriction (reduction of AA diameters by only 9 +/- 2%, P less than 0.001). The subsequent addition of isradipine (0.1-1 microM) did not further dilate AA. Our data indicate that IAA-94 markedly attenuates AA vasoconstriction elicited by ET and suggest that ET-induced opening of chloride channels, membrane depolarization, and subsequent activation of voltage-dependent calcium channels contribute to the vasoconstrictor mechanisms of this peptide.

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32

El-Khatib, Ahmed M., Yehia M. Abbas, Mohamed S. Badawi, Osama M. Hagag i Mahmoud T. Alabsy. "Gamma radiation shielding properties of recycled polyvinyl chloride composites reinforced with micro/nano-structured PbO and CuO particles". Physica Scripta 96, nr 12 (15.11.2021): 125316. http://dx.doi.org/10.1088/1402-4896/ac35c3.

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Abstract In this work, the γ-ray shielding characteristics of fabricated recycled polyvinyl chloride (rPVC) loaded with micro and nano fillers of PbO and CuO composites were investigated. The PbO/rPVC and CuO/rPVC composites were prepared by changing the percentage of injected materials (PbO and CuO) between 10% and 40% with additions by 10%. Gamma-ray attenuation properties, such as mass attenuation coefficients, linear attenuation coefficients and half-value layer for PbO and CuO-supported polymers were obtained in the energy range between 59.5 and 1408.0 keV using narrow beam transmission geometry. These experiments were carried out by using a HPGe detector and five standard radioactive sources [241Am, 133Ba, 137Cs, 60Co and 152Eu]. Moreover, equivalent atomic numbers and the exposure buildup factor (EBF) values for incident photon energy in the range from 0.015 MeV to 15 MeV were also calculated by Geometric Progression (G-P) method. The experimental results revealed that, the measured values of the linear attenuation coefficients of the PbO/rPVC and CuO/rPVC composites showed their dependence on the type and the concentration of the filler (either PbO or CuO) and also on the incident gamma ray energy. Increasing the filler weight fractions wt.% in the rPVC matrix, increases the linear attenuation coefficients of the composite and the improvement is more significant in case of PbO compared to CuO of the same filler wt.% at the same energy. The results also demonstrated an enhancement in the radiation protection behavior of rPVC composites due to the addition of PbO and CuO fillers as nano-sized particles.

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More, Chaitali, Pravina Pawar, Mohamed Badawi i Abouzeid Thabet. "Extensive theoretical study of gamma-ray shielding parameters using epoxy resin-metal chloride mixtures". Nuclear Technology and Radiation Protection 35, nr 2 (2020): 138–49. http://dx.doi.org/10.2298/ntrp2002138m.

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Gamma-ray detection and studying its interactions with matter is very important and serves in many fields of research. Besides, investigation of new shielding materials against gamma-ray will provide a lot of solutions for several problems accompanied by the presence of radiation sources in wide areas of applications, such as industry, medicine, agriculture, research laboratories, and nuclear power plants. In the present work, different gamma-ray attenuation parameters will be calculated theoretically using different metal chlorides mixed with epoxy resin polymers at different weight ratios. These attenuation parameters were calculated in a wide energy range started from 0.05 up to 3 MeV. This wide energy range covers almost the most known radionuclide gamma-ray energies. The obtained results were compared with pure epoxy resin polymer to show how well the modification of polymer properties was when mixed with other materials. Also, all mixture's attenuation parameters results were compared with lead metal results to check its validity as a gamma-ray shielding material. The obtained results found to be promising and the presented materials can be used instead of lead metal as an effective material in radiation protection.

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Motekaitis, A. M., I. C. Solomon i M. P. Kaufman. "Blockade of glutamate receptors in CVLM and NTS attenuates airway dilation evoked from parabrachial region". Journal of Applied Physiology 81, nr 1 (1.07.1996): 400–407. http://dx.doi.org/10.1152/jappl.1996.81.1.400.

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Previous work from our laboratory has shown that stimulation of cell bodies and dendrites in the medial and lateral parabrachial nuclei dilates the airways. The sites participating in the pathway mediating this airway response are not known. Two likely candidates are the caudal ventrolateral medulla (CVLM) and the nucleus tractus solitarii (NTS). Using chloralose-anesthetized cats, we assessed the airway dilation evoked from the parabrachial region before and during bilateral blockade of the NTS or the CVLM. The airway dilation arising from stimulation of the parabrachial region was evoked by microinjection of DL-homocysteic acid (25 nl, 100 mM). Bilateral blockade of the NTS or CVLM, achieved by microinjection of kynurenic acid (50 nl, 100 mM), reversibly attenuated the airway dilation in every cat tested. On average, kynurenic acid-induced blockade of the NTS caused a more complete attenuation of the dilation evoked from the parabrachial region than did blockade of the CVLM. Bilateral microinjection of cobalt chloride (50 nl, 50 mM) into the CVLM gave inconclusive results, attenuating the airway dilation evoked from the parabrachial region in six cats and potentiating it in three others. We conclude that the CVLM and the NTS participate in the airway dilation arising from the parabrachial region.

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Abebe, Worku, i Mahmood S. Mozaffari. "Taurine depletion alters vascular reactivity in rats". Canadian Journal of Physiology and Pharmacology 81, nr 9 (1.09.2003): 903–9. http://dx.doi.org/10.1139/y03-088.

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We recently showed that chronic taurine supplementation is associated with attenuation of contractile responses of rat aorta to norepinephrine and potassium chloride. However, the potential involvement of endogenous taurine in modulation of vascular reactivity is not known. Therefore, we examined the effect of β-alanine-induced taurine depletion on the in vitro reactivity of rat aorta to selected vasoactive agents. The data indicate that both norepinephrine- and potassium-chloride-induced maximum contractile responses of endothelium-denuded aortae were enhanced in taurine-depleted rats compared with control animals. However, taurine depletion did not affect tissue sensitivity to either norepinephrine or potassium chloride. By contrast, sensitivity of the endothelium-denuded aortae to sodium nitroprusside was attenuated by taurine depletion. Similarly, taurine deficiency reduced the relaxant responses of endothelium-intact aortic rings elicited by submaximal concentrations of acetylcholine, and this effect was associated with decreased nitric oxide production. Taken together, the data suggest that taurine depletion augments contractility but attenuates relaxation of vascular smooth muscle in a nonspecific manner. Impairment of endothelium-dependent responses, which is at least in part associated with reduced nitric oxide generation, may contribute to the attenuation of the vasorelaxant responses. These vascular alterations could be of potential consequence in pathological conditions associated with taurine deficiency.Key words: rat aorta, β-alanine, taurine depletion, vascular reactivity.

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Watanabe, Aya, Toshihiro Ichiki, Chikahiro Sankoda, Yusuke Takahara, Jiro Ikeda, Eriko Inoue, Tomotake Tokunou, Shiro Kitamoto i Kenji Sunagawa. "Suppression of abdominal aortic aneurysm formation by inhibition of prolyl hydroxylase domain protein through attenuation of inflammation and extracellular matrix disruption". Clinical Science 126, nr 9 (22.01.2014): 671–78. http://dx.doi.org/10.1042/cs20130435.

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Gu, Lifeng, Guowen Yao, Xuanrui Yu i Qiaoyi Li. "Study on the Durability of the T-Beam Based on Chloride Ion Erosion". Materials 13, nr 7 (25.03.2020): 1504. http://dx.doi.org/10.3390/ma13071504.

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Based on analyzing the bearing capacity of existing T-beam bridges in service, the factors that affect the T-beams cracked by chloride ions mainly include the width and the depth of cracks. Combined with practical engineering examples, a single-piece T-beam model is established to explore the influence of factors such as crack width and crack depth on the T-beams affected by chloride ion erosion through numerical simulation in this paper. In addition, the attenuation models of bending capacity and shear capacity of the T-beam are obtained to analyze the possible failure modes of T-beams with cracks. All of which provides a reference for exploring the effect of crack width and depth on the durability of reinforced concrete members under chloride ion field.

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Rabin, Bernard M., Walter A. Hunt i Jack Lee. "Attenuation and cross-attenuation in taste aversion learning in the rat: Studies with ionizing radiation, lithium chloride and ethanol". Pharmacology Biochemistry and Behavior 31, nr 4 (grudzień 1988): 909–18. http://dx.doi.org/10.1016/0091-3057(88)90404-2.

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Pirozerskiĭ, A. L., E. V. Charnaya, M. I. Vasil’ev i E. L. Lebedeva. "Temperature features of ultrasonic attenuation in photochromic glasses with copper chloride nanocrystals". Acoustical Physics 54, nr 5 (wrzesień 2008): 647–53. http://dx.doi.org/10.1134/s1063771008050084.

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Freedman, D. L., A. S. Danko i M. F. Verce. "Substrate interactions during aerobic biodegradation of methane, ethene, vinyl chloride and 1,2-dichloroethenes". Water Science and Technology 43, nr 5 (1.03.2001): 333–40. http://dx.doi.org/10.2166/wst.2001.0320.

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Intrinsic biodegradation of trichloroethene and 1,1,1-trichloroethane in groundwater at a Superfund site in California has been observed. An anaerobic zone exists in the area closest to the source location, yielding the expected complement of reductive dechlorination daughter products, including cis-1,2-dichloroethene (cis-DCE) and vinyl chloride (VC). Significant levels of methane and ethene were also generated in the anaerobic zone. The groundwater returns to aerobic conditions downgradient of the source, with methane, ethene, VC, and several other compounds still present. Attenuation of VC in the aerobic zone suggests that it is being biodegraded. In this study microcosms were used to evaluate the role of methane and ethene as primary substrates for aerobic biodegradation of VC. Biodegradation of VC was fastest in the bottles containing ethene, with 40 μmol of VC consumed over a 150 day period, compared to approximately 15–20 μmol with methane or a mixture of methane and ethene. VC did not noticeably inhibit ethene biodegradation but did slow the rate of methane use. Methane inhibited ethene metabolism, which apparently caused a reduction in VC biodegradation when methane was present with ethene. These results suggest that ethene plays an important role during in situ natural attenuation of VC under aerobic conditions. Microcosms were also set up with VC alone. Following a 75 day lag period, VC consumption began and subsequent additions were consumed without a lag, suggesting the presence of organisms capable of using VC as a growth substrate. After providing VC alone for nearly 400 days, aliquots of the enrichment culture were used to evaluate its ability to biodegrade cis- and trans-DCE. Both compounds were readily consumed, although addition of VC as the primary substrate was needed to sustain biodegradation of repeated additions. This result suggests that organisms capable of using VC as a sole substrate may play an active role in aerobic natural attenuation of DCEs.

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Yaghi, A., J. T. Hamilton i N. A. M. Paterson. "Influence of platelet-activating factor on leukotriene D4-induced contractions of the guinea pig parenchymal strip". Canadian Journal of Physiology and Pharmacology 67, nr 4 (1.04.1989): 315–21. http://dx.doi.org/10.1139/y89-051.

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Platelet-activating factor (PAF) and sulphidopeptide leukotrienes, such as leukotriene D4 (LTD4), are potent constrictors that are probably released simultaneously in a variety of inflammatory respiratory events. The purpose of the present study was to determine whether LTD4-induced contractions of guinea pig parenchymal lung strips (GPPS) are modified in the presence of PAF. The contractile responses of isolated GPPS to cumulative doses of LTD4, acetylcholine, histamine, and potassium chloride in the presence of PAF (0.1 nM, 0.1 μM) were compared with parallel controls. There was no significant alteration of the response to acetylcholine and potassium chloride and the PAF-induced inhibition of the response to histamine, although significant, was not concentration dependent. In contrast, PAF in a concentration range from 0.1 nM to 1.0 μM caused a marked, concentration-dependent reduction of LTD4-induced contractions. Pretreatment with the PAF receptor antagonist, BN52021, prevented the attenuation of LTD4-induced contraction by PAF. The attenuation of LTD4-induced contraction by PAF was also prevented by pretreatment with indomethacin or with the thromboxane synthase inhibitor U63,557A, but not by pretreatment with the lipoxygenase inhibitors BW755c or nordihydroguaiaretic acid. Thus inhibition of LTD4-induced GPPS contraction by PAF is receptor dependent and probably secondary to thromboxane generation. The respiratory smooth muscle response to leukotrienes may be modified significantly by concomitant PAF release.Key words: platelet-activating factor, leukotriene D4, lung, parenchymal strip, guinea pig.

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Fan, Zhihong, Dagen Su, Zhijie Zhang, Mingfeng Zhong, Xinxing Zhang, Jianbo Xiong i Pengping Li. "Transfer Parameter Analysis of Chloride Ingress into Concrete Based on Long-Term Exposure Tests in China’s Coastal Region". Materials 15, nr 23 (29.11.2022): 8517. http://dx.doi.org/10.3390/ma15238517.

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Chloride penetration resistance is one of the most important performance measures for the evaluation of the durability of concrete under a chloride environment. Due to differences in theory and experimental conditions, the durability index (chloride diffusion coefficient) obtained from laboratory accelerated migration tests cannot reflect the real process of chloride ingress into concrete in the natural environment. The difference in test methods must be considered and the transfer parameter kt should be introduced into the service life prediction model when the test results of accelerated methods are used. According to the test data of coastal exposure in South China, the attenuation rule of the chloride diffusion coefficient of different cement-based materials changed with time and was analyzed in this paper. Based on the diffusion coefficient–time curve, the theoretical natural diffusion coefficients of 28 d and 56 d were deduced, which were compared with the chloride diffusion coefficients obtained from the non-steady-state rapid migration method (RCM) at the same age. Therefore, the transfer parameter kt that expounds the relationship between concrete resistance to chloride permeability under a non-stationary electrical accelerated state and natural diffusion in the marine environment can be calculated; thus, the RCM testing index can be used to evaluate the long-term performance of the concrete structure in the marine environment. The results show that the value of kt was related to environmental conditions, test methods, and binder systems.

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Riess, Matthias L., Janis T. Eells, Leo G. Kevin, Amadou K. S. Camara, Michele M. Henry i David F. Stowe. "Attenuation of Mitochondrial Respiration by Sevoflurane in Isolated Cardiac Mitochondria Is Mediated in Part by Reactive Oxygen Species". Anesthesiology 100, nr 3 (1.03.2004): 498–505. http://dx.doi.org/10.1097/00000542-200403000-00007.

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Background Anesthetic preconditioning protects against cardiac ischemia/reperfusion injury. Increases in reduced nicotinamide adenine dinucleotide and reactive oxygen species during sevoflurane exposure suggest attenuated mitochondrial electron transport as a trigger of anesthetic preconditioning. The authors investigated the effects of sevoflurane on respiration in isolated cardiac mitochondria. Methods Mitochondria were isolated from fresh guinea pig hearts, and mitochondrial oxygen consumption was measured in the presence of complex I (pyruvate) or complex II (succinate) substrates. The mitochondria were exposed to 0, 0.13, 0.39, 1.3, or 3.9 mM sevoflurane. State 3 respiration was determined after adenosine diphosphate addition. The reactive oxygen species scavengers manganese(III) tetrakis (4-benzoic acid) porphyrin chloride and N-tert-Butyl-a-(2-sulfophenyl)nitrone sodium (10 microM each), or the K(ATP) channel blockers glibenclamide (2 microM) or 5-hydroxydecanoate (300 microM), were given alone or before 1.3 mM sevoflurane. Results Sevoflurane attenuated respiration for both complex I and complex II substrates, depending on the dose. Glibenclamide and 5-hydroxydecanoate had no effect on this attenuation. Both scavengers, however, abolished the sevoflurane-induced attenuation for complex I substrates, but not for complex II substrates. Conclusion The findings suggest that sevoflurane-induced attenuation of complex I is mediated by reactive oxygen species, whereas attenuation of other respiratory complexes is mediated by a different mechanism. The opening of mitochondrial K(ATP) channels by sevoflurane does not seem to be involved in this effect. Thus, reactive oxygen species formation may not only result from attenuated electron transport by sevoflurane, but it may also contribute to complex I attenuation, possibly leading to a positive feedback and amplification of sevoflurane-induced reactive oxygen species formation in triggering anesthetic preconditioning.

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Abdul-Majid, Samir, i Fadel Othman. "Neutron Attenuation Characteristics of Polyethylene, Polyvinyl Chloride, and Heavy Aggregate Concrete and Mortars". Health Physics 66, nr 3 (marzec 1994): 327–38. http://dx.doi.org/10.1097/00004032-199403000-00014.

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Teli, M. T., L. M. Chaudhari i S. S. Malode. "Attenuation coefficients of 123 keV γ-radiation by dilute solutions of sodium chloride". Applied Radiation and Isotopes 45, nr 10 (październik 1994): 987–90. http://dx.doi.org/10.1016/0969-8043(94)90166-x.

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Muralidharan, P., i C. Swetha. "Ameliorative Effect of Grape Seed Oil on Aluminium Chloride Induced Neurotoxicity on Rats". Asian Journal of Biochemistry, Genetics and Molecular Biology 14, nr 2 (6.06.2023): 23–30. http://dx.doi.org/10.9734/ajbgmb/2023/v14i2310.

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Aims: Neurodegenerative disorder is characterized by progressive loss of structure and function of neurons. Exposure to aluminum causes neurodegenerative disorders like dementia, and Alzheimer's disease (AD). The present study was designed to examine the ameliorative effect of grape seed oil extraction aluminium chloride induced neurotoxicity in Wistar rats. Methodology: Wistar rats were administered with aluminium chloride (175 mg/kg. p.o.) for 28 days to generate neurotoxicity model. Attenuation effect of grape seed oil against aluminium chloride toxicity by oral administration adjunctly from day 18. Behavioral and locomotor activity was determined using passive avoidance test, open field test, actophotometer and rota rod test. Biochemical parameter such as acetylcholinesterase (AChE) activity andsuperoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) activity were assessed in brain samplesand histology of brain tissue were assessed on the final day of the experiment. Results: Aluminium chloride treatment significantly decreases cognitive function and open field test with a significance decrease in the acetylcholinesterase and antioxidant (SOD, CAT, GR) activity level. Also, the histopathological examination shows significance decrease in the neuronal cell density in hippocampal region. Grape seed oil treated with aluminum chloride neurotoxic groups alleviates all the toxicity induced by the aluminum chloride. Histopathological studies in the hippocampus and cortex of the rat brain also supported that the grape seed oil markedly reduced the toxicity of aluminium chloride. Conclusion: Supplementation of grape seed oilexhibited with beneficial and neuroprotective role on aluminium chloride induced neurotoxicity in Wistar rat modelby improving the cognitive memory and antioxidant enzyme level.

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Tan, Yong, Cheng Gang Hao, De Zhi Li, Zhi Liu Hu i Jian Min Zeng. "Investigation on the Corrosion Behavior of Zn₂₇Al₃Cu Alloy in 3.5 wt.% NaCl Solution". Advanced Materials Research 482-484 (luty 2012): 537–40. http://dx.doi.org/10.4028/www.scientific.net/amr.482-484.537.

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The corrosion behavior of Zn27Al3Cu in 3.5 Wt.% NaCl solution is investigated through weight loss method. The morphology of corrosion products were observed and analyzed with optical microscopy (OM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The experimental results indicate that weight loss of the alloy with time follows the exponential attenuation relationship. Corrosion mechanism of Zn27Al3Cu alloy are intergranular corrosion and preferential corrosion in 3.5 Wt.% NaCl solution, the main corrosion products are compound oxide and chloride.

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Bhosale, Rameshwar, Dhammajyot Gaikwad, Pravina Pawar i Madhav Rode. "Interaction studies and gamma-ray properties of some low-Z materials". Nuclear Technology and Radiation Protection 31, nr 2 (2016): 135–41. http://dx.doi.org/10.2298/ntrp1602135b.

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In present work we use NaI(Tl) detector in narrow-beam good geometry set-up for the gamma ray attenuation studies of some low-Z materials. The parameters such as mass attenuation coefficients, effective atomic numbers and effective electron densities, atomic cross-sections, electronic cross-sections of materials for graphitic powder, polycarbonate, polyvinyl chloride, plaster of Paris, gypsum, and limestone were determined using gamma ray sources 57Co, 133Ba, 137Bs, 60Co, and 22Na at energies of 122, 356, 511, 662, 840, 1170, 1275, and 1330 keV. It was observed that the effective atomic numbers and effective electron densities initially decrease and tend to be almost constant as a function of gamma-ray energy. An attempt was done to check the availability of these low-Z materials at large scales and obtainable at low cost as gamma ray shielding materials. The investigated data are useful in electronic industry, plastic industry, building materials, and agriculture fields.

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Liang, Ye, Tong Xu, Jialiang Zhang, Shuo Li, Ming Qi i Zhe Wang. "Optical property measurements of lithium chloride aqueous solution for a novel solar neutrino experiment". Journal of Instrumentation 18, nr 07 (1.07.2023): P07039. http://dx.doi.org/10.1088/1748-0221/18/07/p07039.

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Abstract The lithium chloride aqueous solution has great potential to be the detection medium of a novel solar neutrino detector. The nuclide 7Li provides a charged-current interaction channel with a high cross-section for the MeV-scale solar electron-neutrinos, enabling measurement of the solar neutrino spectrum. This work measures the optical properties and the light yields of a saturated lithium chloride solution. After adsorption with activated carbon and recrystallization, the solution shows little absorption in the sensitive wavelength range of the bialkali photomultipliers. The attenuation length is evaluated to reach 50 meters at 430 nm. In addition to being a pure Cherenkov detector medium, a wavelength shifter, carbostyril 124, is added to the LiCl aqueous solution. The compatibility and the enhancement of the light yield are confirmed, enabling the development of a water-based Cherenkov-enhanced lithium-rich detector.

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Abbas, Yehia, Ahmed El-Khatib, Mohamed Badawi, Mahmoud Alabsy i Osama Hagag. "Gamma attenuation through nano lead - nano copper PVC composites". Nuclear Technology and Radiation Protection 36, nr 1 (2021): 50–59. http://dx.doi.org/10.2298/ntrp210110001a.

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Polymer composites of polyvinyl chloride, PVC, were loaded up with micro and nano PbO/CuO particles. The added percentage of each by mass was 10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.%, plus 40 wt.% of mixed composite (20 wt.% CuO + 20 wt.% PbO). The mass and linear attenuation coefficients of the investigated composites were measured as a function of gamma-ray energies going from 59.53 keV to 1408.01 keV utilizing standard radioactive point sources. To confirm the validity of these results the attenuation coefficients for bulk composites (PVC + PbO and PVC + CuO) were calculated by using the XCOM software. The results were in good agreement with the values obtained from the experimental work. By comparing the attenuation coefficients of the different composites it was found that those loaded with either nano PbO or CuO have higher values than those loaded with bulk sizes with the same percentage. Also, samples loaded with nano PbO have the highest attenuation coefficients even by comparing them with (20 wt.% CuO + 20 wt.% PbO), especially in the energy region below 1 MeV, but for greater energies, the values become very closed. The investigation of the mechanical properties of such composites due to the injection of bulk and nano metals reveals that tensile strength and Young's modulus of PVC nanocomposite sheets were notably increased with the increasing concentration of CuO and PbO nanoparticles. The CuO nanocomposite showed the highest values of flexural strength, toughness, and tensile strength among all the fabricated nanocomposite sheets.

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