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Analyzing Precipitation Acidity Changes Post Train Derailment and Vinyl Chloride Release in East Palestine, Ohio: Exploring Biomedical and Environmental Ramifications
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作者 Godspower O. Sebe Kristen Vogle +3 位作者 Brendan Meyers Adenike Elizabeth Adewoyin Livina C. Iheme Henrietta Nneka Emeka 《Journal of Water Resource and Protection》 2023年第9期442-480,共39页
This study investigates the aftermath of a significant train derailment and vinyl chloride release incident in East Palestine, Ohio, with a particular focus on the analysis of precipitation acidity changes and the con... This study investigates the aftermath of a significant train derailment and vinyl chloride release incident in East Palestine, Ohio, with a particular focus on the analysis of precipitation acidity changes and the concentration of vinyl chloride in samples. The research seeks to elucidate the complex relationship between industrial accidents, atmospheric chemistry, and their potential implications for human health and the environment. Through meticulous examination of variations in precipitation acidity patterns, this study provides valuable insights into the dispersion and impact of toxic agents in the environment following industrial mishaps. The results underscore the intricate interplay between these factors, highlighting the need for a multidisciplinary approach that bridges the realms of environmental science and biomedical concerns. This research contributes to a growing body of knowledge that addresses the broader consequences of industrial incidents on public health. It underscores the importance of proactive measures, such as enhanced monitoring and surveillance, risk assessment, public education, and regulatory reform, to mitigate the environmental and health risks associated with industrial activities involving hazardous materials. By fostering collaboration between experts and stakeholders, this study advocates for a holistic approach to safeguarding both our environment and the well-being of communities affected by industrial accidents. 展开更多
关键词 pH precipitation East Palestine ANOVA Environment Vinyl Chloride Health
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Influence of secondary carbide precipitation and transformation on abrasion resistance of a 3Cr15Mo1V1.5 white iron 被引量:4
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作者 Haohuai Liu Jun Wang +3 位作者 Baoluo Shen Hongshan Yang Shengji Gao Sijiu Huang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第3期231-235,共5页
The relationship between the secondary carbide precipitation and transformation of the 3Cr15Mo1V1.5 white iron and abrasion resistance was investigated by using optical microscope (OM), transmission electron microsc... The relationship between the secondary carbide precipitation and transformation of the 3Cr15Mo1V1.5 white iron and abrasion resistance was investigated by using optical microscope (OM), transmission electron microscopy (TEM) and X-ray diffrac- tion (XRD). The results show that the properties of secondary carbides precipitated at holding stage play an important role in the abrasion resistance. After certain holding time at 833 K subcritical treatment, the grainy (Fe, Cr)23C6 carbide precipitated and the fresh martensite transformed at the holding stage for 3Cr15Mo1V1.5 white iron improve the bulk hardness and abrasion resistance of the alloy. Prolonging holding time, MoC and (Cr, V)2C precipitations cause the secondary hardening peak and the corresponding better abrasion resistance. Finally, granular (Fe, Cr)23C6 carbide in situ transforms into laminar M3C carbide and the matrix structure transforms into pearlitic matrix. These changes weaken hardness and abrasion resistance of the alloy sharply. 展开更多
关键词 high chromium white iron abrasion resistance secondary carbide precipitation
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Effect of titanium content on the precipitation behavior of carbon-saturated molten pig iron 被引量:2
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作者 Lei-zhang Gao Tong-xiang Ma +3 位作者 Meng-jun Hu Zhi-ming Yan Xue-wei Lü Mei-long Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第4期483-492,共10页
The use of iron ores bearing titanium as a raw material is an effective measure to prevent hearth erosion and prolong the life of a blast furnace. In this research, the effect of titanium content on the precipitation ... The use of iron ores bearing titanium as a raw material is an effective measure to prevent hearth erosion and prolong the life of a blast furnace. In this research, the effect of titanium content on the precipitation behaviors of high-melting phases of carbon-saturated molten pig iron were studied by confocal scanning laser microscopy. The results showed that, when the titanium content was less than 0.25 wt%,Fe_3C was precipitated as a single phase from the molten carbon-saturated iron. The growth rate of the precipitated Fe_3C crystals was very high, reaching 7387 μm^2/s. When the titanium content in the molten pig iron was greater than 0.47 wt%, TiC crystals precipitated first. The shape and size of the precipitated TiC crystals did not obviously change. After TiC was precipitated, the fluidity of the molten pig iron worsened. With a decrease in temperature, Fe_3C was also precipitated but the growth rate of Fe_3C was limited by the presence of the first precipitated TiC phase. The crystal size of the precipitated Fe_3C was much smaller than that of pure Fe_3C. 展开更多
关键词 carbon-saturated MOLTEN pig iron precipitation behavior TITANIUM TITANIUM CARBIDE CONFOCAL scanning laser microscopy
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Transformation behavior of ferrous sulfate during hematite precipitation for iron removal 被引量:6
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作者 Zhi-gan DENG Fan YANG +5 位作者 Chang WEI Bei-ping ZHU Peng ZENG Xing-bin LI Cun-xiong LI Min-ting LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第2期492-500,共9页
The transformation behavior of ferrous sulfate was examined during hematite precipitation for iron removal in hydrometallurgical zinc.Specifically,the effects of the method used for oxygen supply(pre-crystallization o... The transformation behavior of ferrous sulfate was examined during hematite precipitation for iron removal in hydrometallurgical zinc.Specifically,the effects of the method used for oxygen supply(pre-crystallization or pre-oxidation of ferrous sulfate)and temperature(170–190℃)on the redissolution and oxidation–hydrolysis of ferrous sulfate were studied.The precipitation characteristics and phase characterization of the hematite product were investigated.The results showed that the solubility of ferrous sulfate was considerably lower at elevated temperatures.The dissolution behavior of ferrous sulfate crystals was influenced by both the concentrations of free acid and zinc sulfate and the oxydrolysis of ferrous ions.Rapid oxydrolysis of ferrous ions may serve as the dissolution driving force.Hematite precipitation proceeded via the following sequential steps:crystallization,redissolution,oxidation,and precipitation of ferrous sulfate.The dissolution of ferrous sulfate was slow,which helped to maintain a low supersaturation environment,thereby affording the production of high-grade hematite. 展开更多
关键词 hydrometallurgical zinc crystallization of ferrous sulfate hematite precipitation for iron removal
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Soil Organic Carbon and Labile Carbon Along a Precipitation Gradient and Their Responses to Some Environmental Changes 被引量:12
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作者 WANG Shu-Ping ZHOU Guang-Sheng +1 位作者 GAO Su-Hua GUO Jian-Ping 《Pedosphere》 SCIE CAS CSCD 2005年第5期676-680,共5页
Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mo... Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mol-1with different soil moisture contents of 30%-45%, 45%-60%, and 60%-80% soil water holding capacity, the distributionof soil organic carbon and labile carbon along the NECT, their relationships with precipitation and their responses toCO2 enrichment and soil moisture changes were analyzed. The results indicated that the soil labile carbon along thegradient was significantly related to soil organic carbon (r = 0.993, P < 0.001). The soil labile carbon decreased morerapidly with depth than organic carbon. The soil organic and labile carbon along the gradient decreased with decrease inlongitude in both the topsoils and subsoils, and the coefficient of variation for the labile carbon was greater than that forthe organic carbon. Both the soil organic carbon and labile carbon had significant linear relationships with precipitation,with the correlation coefficient of soil organic carbon being lower (0.677 at P < 0.001) than that of soil labile carbon(0.712 at P < 0.001). In the simulation experiment with doubled and ambient CO2 and different moisture contents, thecoefficient of variation for soil organic carbon was only 1.3%, while for soil labile carbon it was 29.7%. With doubled CO2concentration (700 μmol mol-1), soil labile carbon decreased significantly at 45% to 60% of soil moisture content. Theseindicated that soil labile carbon was relatively more sensitive to environmental changes than soil organic carbon. 展开更多
关键词 environmental changes labile carbon organic carbon precipitation gradient SOIL
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Modeling of goethite iron precipitation process based on time-delay fuzzy gray cognitive network 被引量:1
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作者 CHEN Ning ZHOU Jia-qi +2 位作者 PENG Jun-jie GUI Wei-hua DAI Jia-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第1期63-74,共12页
The goethite iron precipitation process consists of several continuous reactors and involves a series of complex chemical reactions,such as oxidation reaction,hydrolysis reaction and neutralization reaction.It is hard... The goethite iron precipitation process consists of several continuous reactors and involves a series of complex chemical reactions,such as oxidation reaction,hydrolysis reaction and neutralization reaction.It is hard to accurately establish a mathematical model of the process featured by strong nonlinearity,uncertainty and time-delay.A modeling method based on time-delay fuzzy gray cognitive network(T-FGCN)for the goethite iron precipitation process was proposed in this paper.On the basis of the process mechanism,experts’practical experience and historical data,the T-FGCN model of the goethite iron precipitation system was established and the weights were studied by using the nonlinear hebbian learning(NHL)algorithm with terminal constraints.By analyzing the system in uncertain environment of varying degrees,in the environment of high uncertainty,the T-FGCN can accurately simulate industrial systems with large time-delay and uncertainty and the simulated system can converge to steady state with zero gray scale or a small one. 展开更多
关键词 time-delay fuzzy gray cognitive network(T-FGCN) iron precipitation process nonlinear Hebbian learning
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Structural Analysis of Magnesium-Aluminium Hydrotalcites Modified with Iron III Obtained by Hydroxide Precipitation Method
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作者 Graciele Vieira Barbosa Maria Aparecida Zaghete +3 位作者 Rafael Aparecido Ciola Amoresi Margarete Soares da Silva Alberto Adriano Cavalheiro Rogério Cesar de Lara da Silva 《Materials Sciences and Applications》 2017年第11期784-797,共14页
Hydrotalcite-type anionic clays are a group of important materials used in adsorption processes, mainly for organic pollutants removal due the layered double hydroxide structure. The layer-interlayer interactions prov... Hydrotalcite-type anionic clays are a group of important materials used in adsorption processes, mainly for organic pollutants removal due the layered double hydroxide structure. The layer-interlayer interactions provide a structural memory even after dehydration and dehydroxylation process, since a very stable interlayer anions are part of material composition, like the carbonate one. A limited numbers of trivalent modifier cations can replace the aluminium cation due the ionic radii mismatch or oxidation state restrictions. Transition metal cations can replace the aluminium one in octahedral site of hydroxide lamellas in order to improve the adsorptive behaviors. In this work, we have investigate three compositions of carbonated magnesium-aluminium hydrotalcite with dif-ferent iron (III) contents through the co-precipitation method at pH 11 and aging step at 60°C for 6 hours. Thermal analysis was performed aiming the determination of the hydration water and hydroxyl amounts in dried precipitate samples, taking in account the results obtained for X-ray diffractometry, infrared spectroscopy, and nitrogen adsorption-desorption characterization for several thermally treated samples. All of synthesized samples showed high surface areas, even for high temperature of thermal treatment. The co-substitution with iron (III) reduced the temperature of dehydration and dehydroxylation process, but the co-substitution at 5 mol% provides other desirables characteristics, like a more amount of rhombohedral HDL phase and higher porosity, even after the thermal treatment at 500°C for 4 hours. This result makes that composition very applicable as a reusable adsorbent material in order to removal several types of micro-pollutant compounds in aqueous media. 展开更多
关键词 HYDROTALCITE LAYERED Double HYDROXIDE HYDROXIDE precipitation iron (III)
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Process for recycle of spent lithium iron phosphate battery via a selective leaching-precipitation method 被引量:22
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作者 LI Hao-yu YE Hua +1 位作者 SUN Ming-cang CHEN Wu-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第11期3239-3248,共10页
Applying spent lithium iron phosphate battery as raw material,valuable metals in spent lithium ion battery were effectively recovered through separation of active material,selective leaching,and stepwise chemical prec... Applying spent lithium iron phosphate battery as raw material,valuable metals in spent lithium ion battery were effectively recovered through separation of active material,selective leaching,and stepwise chemical precipitation.Using stoichiometric Na2S2O8 as an oxidant and adding low-concentration H2SO4 as a leaching agent was proposed.This route was totally different from the conventional methods of dissolving all of the elements into solution by using excess mineral acid.When experiments were done under optimal conditions(Na2S2O8-to-Li molar ratio 0.45,0.30 mol/L H2SO4,60℃,1.5 h),leaching efficiencies of 97.53% for Li^+,1.39%for Fe^3+,and 2.58% for PO4^3−were recorded.FePO4 was then recovered by a precipitation method from the leachate while maintaining the pH at 2.0.The mother liquor was concentrated and maintained at a temperature of approximately 100℃,and then a saturated sodium carbonate solution was added to precipitate Li2CO3.The lithium recovery yield was close to 80%. 展开更多
关键词 lithium iron phosphate batteries selective leaching RECOVERY sodium persulfate lithium carbonate
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Complexity analysis of precipitation in changing environment in Chien River Basin,China 被引量:3
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作者 Qing-hua LUAN Hao WANG Da-zhong XIA 《Water Science and Engineering》 EI CAS 2011年第2期133-142,共10页
The hydrological processes influenced by the multiple factors of climate, geography, vegetation, and human activities are becoming more and more complex, which is an important characteristic of hydrological systems. T... The hydrological processes influenced by the multiple factors of climate, geography, vegetation, and human activities are becoming more and more complex, which is an important characteristic of hydrological systems. The different complexity distributions of precipitation processes of the Chien River Basin (a sub-basin of the Minjiang Basin) in two periods (from 1952 to 1980, and from 1981 to 2009) are illustrated using the fractal based on the continuous wavelet transform (CWT). The results show that (1) at the basin scale the precipitation process in the latter period is more complex than in the former period; (2) the maximum value of the complexity distribution moved from the east to the middle; and (3) through analysis of the time-information and space-information concealed in this complexity change, the precipitation characteristics in the changing environment in the basin can be illuminated. This study could provide a reference for research on disaster pre-warning in changing environments and for integrated water resources management in the local basin. 展开更多
关键词 characteristic analysis precipitation complexity continuous wavelet transform fractal: Chien River Basin
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Preparation of YAG Powder by Co-Precipitation Method in a Narrow pH-Change Environment 被引量:1
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作者 马奔原 卢铁城 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期379-383,共5页
YAG(Y3Al5O12) powder was prepared by co-precipitation method.To avoid pH values changing intensely during titration process,the 4 3 NH HCO solution with 4 3 NH NO was used as precipitant solution.The pH change of pr... YAG(Y3Al5O12) powder was prepared by co-precipitation method.To avoid pH values changing intensely during titration process,the 4 3 NH HCO solution with 4 3 NH NO was used as precipitant solution.The pH change of precipitant solution during titration process,compositions of precursor,phase formation process and morphology of the prepared powder were investigated by means of pH meter,FT-IR,XRD and TEM.The results show that the presence of 4 3 NH NO in 4 3 NH HCO solution is crucial to alleviate the pH change,lower the calcination temperature and meliorate the morphology of YAG powder.The mechanisms were studied in detail.The YAG phase can be obtained at a lower temperature of 900 ℃.The obtained powder,composed of elliptical particles,showed a meliorated morphology. 展开更多
关键词 precipitation CHEMISTRY POWDER CERAMICS
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Precipitation and evolution of nodular graphite during solidification process of ductile iron 被引量:6
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作者 Jin-hai Liu Jian-shuai Yan +4 位作者 Xue-bo Zhao Bin-guo Fu Hai-tao Xue Gui-xian Zhang Peng-hui Yang 《China Foundry》 SCIE 2020年第4期260-271,共12页
The quantity and morphology of spheroidal graphite have an important effect on the properties of ductile iron, and the characteristics of spheroidal graphite are determined by the solidification process. The aim of th... The quantity and morphology of spheroidal graphite have an important effect on the properties of ductile iron, and the characteristics of spheroidal graphite are determined by the solidification process. The aim of this work is to explore the precipitation and evolution of graphite nodules in hypoeutectic, eutectic, and hypereutectic ductile irons by thermal analysis, liquid quenching and metallographic technique. Results show that hypoeutectic ductile iron has the longest solidification time and the lowest eutectic temperature;eutectic ductile iron has the shortest solidification time;hypereutectic ductile iron has the highest eutectic temperature. After solidification is completed, hypoeutectic ductile iron has the lowest nodule count, nodularity and graphite fraction;eutectic ductile iron has the highest nodule count, nodularity and the smallest nodule diameter;hypereutectic has the highest nodule diameter and graphite fraction. The nucleation and growth of graphite nodules in hypereutectic ductile iron starts before bulk eutectic crystallization stage, however, the precipitation and evolution of graphite nodules of hypoeutectic and eutectic ductile irons mainly occur in the eutectic crystallization stage. The graphite precipitated in eutectic crystallization of hypoeutectic, eutectic, and hypereutectic ductile irons, are 61%, 68% and 43% of total graphite volume fraction, respectively. Simultaneously, there are plenty of austenite dendrites in hypoeutectic and hypereutectic ductile irons, which are prone to shrinkage defects. Therefore, the eutectic ductile iron has the smallest shrinkage tendency. 展开更多
关键词 ductile iron carbon equivalent graphite nodules SOLIDIFICATION thermal analysis liquid quenching
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Source and level of dietary iron influence semen quality by affecting inflammation, oxidative stress and iron utilization levels in boars
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作者 Yinghui Wu Yamei Li +8 位作者 Yueyue Miao Hongkui Wei Hefeng Luo Chunxiao Ren Yawei Zhang Juan Chen Tanghong Wei Jiyan Deng Jian Peng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2044-2058,共15页
Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be... Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be inappropriate.Therefore,56 healthy Topeka E line boars aged 15–21 months were randomly divided into 5 groups:basal diet supplemented with 96 mg/kg ferrous sulfate(FeSO_(4))and 54 mg/kg glycine chelated iron(Gly-Fe,control);80 mg/kg or 115 mg/kg Gly-Fe;80 mg/kg or 115 mg/kg methionine hydroxyl analogue chelated iron(MHA-Fe,from CalimetFe)for 16 weeks.The effects of dietary iron supplementation with different sources and levels on semen quality in boars were investigated.Results 1)Serum Fe and hemoglobin concentrations were not affected by reduced dietary iron levels in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups compared with the control group(P>0.05).2)Serum interleukin-6(IL-6)and sperm malondialdehyde(MDA)levels in the 80 mg/kg or 115 mg/kg MHA-Fe groups were lower than those in the control group(P<0.05),and higher serum superoxide dismutase levels and lower MDA levels in the 115 mg/kg MHA-Fe group(P<0.05).3)Boars in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups had lower serum hepcidin(P<0.01),ferritin(P<0.05),and transferrin receptor(P<0.01)concentrations,and boars in the 115 mg/kg MHA-Fe group had higher seminal plasma Fe concentrations compared with the control group.4)Boars in the 80 mg/kg and 115 mg/kg MHA-Fe groups had lower abnormal sperm rate and in situ oscillating sperm ratio compared to the control group at weeks 12 and/or 16 of the trial.However,the effect of Gly-Fe on improving semen quality in boars was not evident.5)Serum IL-6 level was positively correlated with hepcidin concentration(P<0.05),which in turn was significantly positively correlated with abnormal sperm rate(P<0.05).Furthermore,significant correlations were also found between indicators of iron status and oxidative stress and semen quality parameters.Conclusions Dietary supplementation with 80 mg/kg or 115 mg/kg MHA-Fe did not induce iron deficiency,but rather reduced serum inflammatory levels and hepcidin concentration,alleviated oxidative stress,increased body iron utilization,and improved semen quality in adult boars. 展开更多
关键词 Adult boars iron level iron source iron status Semen quality
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Parenteral iron therapy in children with iron deficiency anemia
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作者 Jelena Roganovic 《World Journal of Clinical Cases》 SCIE 2024年第13期2138-2142,共5页
Iron deficiency anemia(IDA)continues to be a global public health problem.Oral iron is the universally accepted first-line therapy,and most children have a prompt and favorable response to oral formulations.In subsets... Iron deficiency anemia(IDA)continues to be a global public health problem.Oral iron is the universally accepted first-line therapy,and most children have a prompt and favorable response to oral formulations.In subsets of children who fail to respond due to intolerance,poor adherence,or inadequate intestinal absorption,parenteral iron is indicated.Despite numerous studies in adults with IDA of diverse etiologies,pediatric studies on parenteral iron use are very limited.Although mostly retrospective and small,these studies have documented the efficacy and safety profile of intravenous iron formulations.In this editorial the author comments on the most important published data and underscores the need to seriously consider parenteral iron use in children unresponsive to oral therapy. 展开更多
关键词 ANEMIA iron deficiency Intravenous iron iron deficiency anemia CHILDREN
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Effect of Addition Sequence during Neutralization and Precipitation on Iron-based Catalysts for High Temperature Shift Reaction 被引量:1
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作者 Li Wei Zhu Jianhua Mou Zhanjun 《Petroleum Science》 SCIE CAS CSCD 2007年第1期75-80,共6页
The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials durin... The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials during neutralization and precipitation was investigated. XRD, BET and particle size distribution (PSD) were used to characterize the prepared catalysts. It was found that the catalyst crystals were all γ-Fe2O3, and the intermediate of the catalyst after aging was Fe3O4. The crystallographic form of the catalyst and its intermediate was not affected by the addition sequence in the neutralization and precipitation process. The results showed that the specific surface area and the particle size of the catalysts depended on the addition sequence to the mother liquor. Cobalt with a small amount of copper and aluminum could increase the specific surface area and decrease the particle size of catalysts. 展开更多
关键词 Water gas shift reaction Γ-FE2O3 cobalt-promoted catalyst iron-based catalyst
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Two-stage precipitation process of iron and arsenic from acid leaching solutions 被引量:3
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作者 N. J. BOLIN J. E. SUNDKVIST 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第6期1513-1517,共5页
为贱金属恢复的沥滤的进程经常产生象铁和砷那样的杂质的可观的数量进解决方案。为最后的处理把非珍贵的金属分开成可管理、稳定的废物产品是挑战,没有松开珍贵成分。Boliden 矿物质 AB 获给很干净的铁砷的一个二阶段的降水过程专利由... 为贱金属恢复的沥滤的进程经常产生象铁和砷那样的杂质的可观的数量进解决方案。为最后的处理把非珍贵的金属分开成可管理、稳定的废物产品是挑战,没有松开珍贵成分。Boliden 矿物质 AB 获给很干净的铁砷的一个二阶段的降水过程专利由贱金属的最少一起沉淀猛抛。有好沉积和过滤性质的获得的产品表演,它使恢复铁砷容易弄空由过滤的答案并且 precipitate 洗。键盘乐器的低音部凳子规模测试被做了,显示出二阶段的降水过程完成的优秀结果。 展开更多
关键词 提取 生物浸取 沉淀
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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases 被引量:1
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作者 Yating ZHAO Ming XUE +2 位作者 Jing JIANG Xiao-Ming HU Anning HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期619-638,共20页
Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss pos... Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios. 展开更多
关键词 NARCCAP Central United States precipitation low-level jet large-scale environment diurnal variation
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Iron and Heart Failure: Current Concepts and Emerging Pharmacological Paradigms
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作者 Maria Rosaria De Pascale Maria Beatrice Rondinelli +5 位作者 Flora Ascione Vincenzo Maffei Chiara Di Lorenzo Sarah Scagliarini Raffaella Faraonio Antonio Faiella 《World Journal of Cardiovascular Diseases》 CAS 2024年第4期195-216,共22页
Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial a... Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial asset and clinical scenario in HF. Purpose: Recent acquisitions suggest that iron deficiency represents a concrete bias in the pathogenetic mechanism of chronic HF, so we have investigated the putative role of the hepcidin/ferroportin axis in the cardiovascular setting to advocate novel pharmacological and clinical approaches. Methods: Here, after an excursus on iron metabolism, we first reviewed the ongoing studies on novel iron targeted compounds. Then, we summarize large clinical interventional studies conducted on patient suffering from iron deficiency and HF which have tested the effects of drugging iron regard QoL, hospitalizations and cardiovascular death. Results: Novel compounds such as hepcidin agonist (PTG 300), synthetic human hepcidin (LJPC-401) and anti FPN (Vamifeport) are ongoing in iron overloaded patients, while the hepcidin blocker (PRS-080) is under investigation in anemic patients. Noteworthy, novel insights could arise from the results of a Phase IV interventional study regarding the modification of hepcidin pathway in a large cohort of HF patients (n = 1992) by sodium glucose cotransporter 2 inhibitors. To date, several studies highlight the beneficial effect of iron administration in cardiovascular setting and latest evidences consider hepcidin level as a novel biomarker of cardiac injury and atherosclerosis. Conclusions: We advocate that data from ongoing studies will suggest novel iron targeted therapies for diagnosis, prognosis and therapy transferable in selected heart failed patients. 展开更多
关键词 Heart Failure iron ANEMIA iron Deficiency HEPCIDIN
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A New Algorithm of Rain Type Classification for GPM Dual-Frequency Precipitation Radar in Summer Tibetan Plateau
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作者 Yunfei FU Liu YANG +4 位作者 Zhenhao WU Peng ZHANG Songyan GU Lin CHEN Sun NAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2093-2111,共19页
In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar(DPR) suitable over the Tibetan Plateau(TP) was proposed by analyzing Global Precipitation Measurement(GPM) DPR Level-2... In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar(DPR) suitable over the Tibetan Plateau(TP) was proposed by analyzing Global Precipitation Measurement(GPM) DPR Level-2 data in summer from 2014 to 2020. It was found that the DPR rain type classification algorithm(simply called DPR algorithm) has mis-identification problems in two aspects in summer TP. In the new algorithm of rain type classification in summer TP,four rain types are classified by using new thresholds, such as the maximum reflectivity factor, the difference between the maximum reflectivity factor and the background maximum reflectivity factor, and the echo top height. In the threshold of the maximum reflectivity factors, 30 d BZ and 18 d BZ are both thresholds to separate strong convective precipitation, weak convective precipitation and weak precipitation. The results illustrate obvious differences of radar reflectivity factor and vertical velocity among the three rain types in summer TP, such as the reflectivity factor of most strong convective precipitation distributes from 15 d BZ to near 35 d BZ from 4 km to 13 km, and increases almost linearly with the decrease in height. For most weak convective precipitation, the reflectivity factor distributes from 15 d BZ to 28 d BZ with the height from 4 km to 9 km. For weak precipitation, the reflectivity factor mainly distributes in range of 15–25 d BZ with height within 4–10 km. It is also shows that weak precipitation is the dominant rain type in summer TP, accounting for 40%–80%,followed by weak convective precipitation(25%–40%), and strong convective precipitation has the least proportion(less than 30%). 展开更多
关键词 satellite precipitation radar rain type classification method Tibetan Plateau strong convective precipitation
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The Influence of Airflow Transport Pathways on Precipitation during the Rainy Season in the Liupan Mountains of Northwest China
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作者 Yujun QIU Chunsong LU +1 位作者 Zhiliang SHU Peiyun DENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2215-2229,共15页
This study investigates the influence of airflow transport pathways on seasonal rainfall in the mountainous region of the Liupan Mountains(LM) during the rainy seasons from 2020 to 2022, utilizing observational data f... This study investigates the influence of airflow transport pathways on seasonal rainfall in the mountainous region of the Liupan Mountains(LM) during the rainy seasons from 2020 to 2022, utilizing observational data from seven ground gradient stations located on the eastern slopes, western slopes, and mountaintops combined with backward trajectory cluster analysis. The results indicate 1) that the LM's rainy season, characterized by overcast and rainy days, is mainly influenced by cold and moist airflows(CMAs) from the westerly direction and warm and moist airflows(WMAs) from a slightly southern direction. The precipitation amounts under four airflow transport paths are ranked from largest to smallest as follows: WMAs, CMAs, warm dry airflows(WDAs), and cold dry airflows(CDAs). 2) WMAs contribute significantly more to the intensity of regional precipitation than the other three types of airflows. During localized precipitation events,warm airflows have higher precipitation intensities at night than cold airflows, while the opposite is true during the afternoon. 3) During regional precipitation events, water vapor content is the primary influencing factor. Precipitation characteristics under humid airflows are mainly affected by high water vapor content, whereas during dry airflow precipitation, dynamic and thermodynamic factors have a more pronounced impact. 4) During localized precipitation events, the influence of dynamic and thermodynamic factors is more complex than during regional precipitation, with the precipitation characteristics of the four airflows closely related to their water vapor content, air temperature and humidity attributes, and orographic lifting. 5) Compared to regional precipitation, the influence of topography is more prominent in localized precipitation processes. 展开更多
关键词 regional precipitation localized precipitation airflow transport water vapor flux instability energy topographic influence
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Improving the accuracy of precipitation estimates in a typical inland arid area of China using a dynamic Bayesian model averaging approach
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作者 XU Wenjie DING Jianli +2 位作者 BAO Qingling WANG Jinjie XU Kun 《Journal of Arid Land》 SCIE CSCD 2024年第3期331-354,共24页
Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water scarcity.Evaluating a... Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water scarcity.Evaluating and integrating precipitation datasets from different sources to accurately characterize precipitation patterns has become a challenge to provide more accurate and alternative precipitation information for the region,which can even improve the performance of hydrological modelling.This study evaluated the applicability of widely used five satellite-based precipitation products(Climate Hazards Group InfraRed Precipitation with Station(CHIRPS),China Meteorological Forcing Dataset(CMFD),Climate Prediction Center morphing method(CMORPH),Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record(PERSIANN-CDR),and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis(TMPA))and a reanalysis precipitation dataset(ECMWF Reanalysis v5-Land Dataset(ERA5-Land))in Xinjiang using ground-based observational precipitation data from a limited number of meteorological stations.Based on this assessment,we proposed a framework that integrated different precipitation datasets with varying spatial resolutions using a dynamic Bayesian model averaging(DBMA)approach,the expectation-maximization method,and the ordinary Kriging interpolation method.The daily precipitation data merged using the DBMA approach exhibited distinct spatiotemporal variability,with an outstanding performance,as indicated by low root mean square error(RMSE=1.40 mm/d)and high Person's correlation coefficient(CC=0.67).Compared with the traditional simple model averaging(SMA)and individual product data,although the DBMA-fused precipitation data were slightly lower than the best precipitation product(CMFD),the overall performance of DBMA was more robust.The error analysis between DBMA-fused precipitation dataset and the more advanced Integrated Multi-satellite Retrievals for Global Precipitation Measurement Final(IMERG-F)precipitation product,as well as hydrological simulations in the Ebinur Lake Basin,further demonstrated the superior performance of DBMA-fused precipitation dataset in the entire Xinjiang region.The proposed framework for solving the fusion problem of multi-source precipitation data with different spatial resolutions is feasible for application in inland arid areas,and aids in obtaining more accurate regional hydrological information and improving regional water resources management capabilities and meteorological research in these regions. 展开更多
关键词 precipitation estimates satellite-based and reanalysis precipitation dynamic Bayesian model averaging streamflow simulation Ebinur Lake Basin XINJIANG
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