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Mechanism of MoO2 electrodeposition from ammonium molybdate solution

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Transactions of Nonferrous Metals Society of China 2019年第8期29卷 1744-1752页

作者： Hua-zhen CAO Cheng-jian TONG Hui-bin ZHANG guo-qu zheng College of Materials Science and Engineering Zhejiang University of Technology Hangzhou 310014 China

A mechanism study on MoO2 electrodeposition from ammonium molybdate solution was presented via linear sweep voltammetry,species distribution diagram,Raman spectra,Fourier transform infrared spectrometry and X-ray *** results show that there exist two reducible species in ammonium molybdate aqueous solution,***7 O24^6- and molybdenum ammonium *** weak acid medium without NH4^+,an obvious reduction peak denoting the reduction of Mo7 O24^6- to molybdenum(Ⅳ)oxides emerges at around-0.7 V(vs SCE).While in neutral and basic solutions without NH4^+,the dominant species changes to MoO4^2-,and accordingly,no reduction peak appears except hydrogen ***4^+ plays an important role in MoO2 electrodeposition.A new current peak appears at-1.25 V(vs SCE)in both acid and basic solutions,which is attributed to the reduction of molybdenum *** effects of solution composition and the electrodeposition conditions on the current efficiency were discussed *** optimizing the electrodeposition conditions,the current efficiency can reach up to51.9%.

关键词： MoO2 NH4+ sodium molybdate electrodeposition current efficiency mechanism

Chlorine inclusion mechanism in high purity copper electrorefining from nitric acid system

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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1387-1396页

作者： Hua-zhen CAO Wen-yu FENG Hui-bin ZHANG guo-qu zheng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China

A practical approach was introduced to study the inclusion mechanism of chlorine in high purity copper electrorefining from nitric acid system via cyclic voltammetry(CV) combined with electrodeposition experiments. The CV curves display an obvious reduction peak of Cu Cl intermediate, which can provide an insight into the electrochemical behavior of this inclusion. Experimental results show that the increase of HNO3 concentration is favorable to reducing the quantity of chlorine inclusion although there is a slight decline in cathodic current efficiency. The optimum conditions for copper electrorefining in nitric acid system are HNO3 concentration in solution of 1-2 mol/L, moderate temperature of ~35 ℃ with current density not exceeding 25 m A/cm2. Based on the theoretical studies, an optimized copper electrorefining experiment was designed to simulate the industrial electrolysis, by which high purity copper can be obtained with chlorine inclusion less than 10 μg/g and current efficiency higher than 90%.

关键词： copper electrorefining nitric acid system cuprous chlorine inclusion mechanism

Dynamic changes of IL-2/IL-10, sFas and expression of Fas in intestinal mucosa in rats with acute necrotizing pancreatitis

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World Journal of Gastroenterology 2008年第14期14卷 2246-2250页

作者： Sheng-Chun Dang Jian-Xin Zhang Jian-guo qu zheng-Fa Mao Xu-Qing Wang Bei Zhu Department of General Surgery The Affiliated Hospital of Jiangsu University Zhenjiang 212001 Jiangsu Province China

AIM:To investigate dynamic changes of serum IL-2, IL-10, IL-2/IL-10 and sFas in rats with acute necrotizing pancreatitis. To explore the expression of Fas in intestinal mucosa of rats with acute necrotizing pancreatitis (ANP). METHODS:A total of 64 Sprague-Dawley (SD) rats were randomly divided into two groups:normal control group (C group), ANP group (P group). An ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane. Normal control group received isovolumetric injection of 9 g/L physiological saline solution using the same method. The blood samples of the rats in each group were obtained via superior mesenteric vein to measure levels of IL-2, IL-10, sFas and calculate the value of IL-2/IL-10. The levels of IL-2, IL-10 and sFas were determined by ELISA. The severity of intestinal mucosal injury was evaluated by pathologic score. The expression of Fas in intestinal mucosal tissue was determined by immunohistochemistry staining. RESULTS:Levels of serum IL-2 were significantly higher in P group than those of C group (2.79 ± 0.51 vs 3.53 ± 0.62, 2.93 ± 0.89 vs 4.35 ± 1.11, 4.81 ± 1.23 vs 6.94 ± 1.55 and 3.41 ± 0.72 vs 4.80 ± 1.10, respectively, P 0.05). In sFas assay, there was no significant difference between P group and C group (3.16 ± 0.75 vs 3.31 ± 0.80,

关键词： Acute necrotizing pancreatitis Fas Intestinal mucosal injury T helper cell

Assessment of selective sequential extraction procedure for determining arsenic partitioning in copper slag

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Transactions of Nonferrous Metals Society of China 2020年第10期30卷 2823-2835页

作者： Hui-bin ZHANG Yu-zheng HE Jing-jing HU Ya-nan WANG Hua-zhen CAO Jun ZHOU guo-qu zheng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China Tongling Nonferrous Metals Group Tongling 244000China

An optimized selective sequential extraction(SSE)procedure was developed to assess the arsenic(As)partitioning in copper *** potential As species in copper slag are partitioned into the readily soluble As,dissolvable arsenates,sparingly soluble arsenates,As residing in sulfides,arsenopyrite and metal As,as well as As incorporated into glassy *** inductively coupled plasma atomic emission spectrometry(ICP-AES),scanning electronic microscopy(SEM),transmission electron microscope(TEM),X-ray diffractometry(XRD)and Fourier transform infrared spectroscopy(FTIR)were used to characterize the leachates and residues produced from the operation *** selectivity and recovery of extractants were evaluated through single-phase extraction *** data of As in slag samples show good agreement with the reported works and the total As recovery of each operation is over 90%.This suggests that the optimized SEE scheme can be reliably employed for As partitioning in As-bearing byproducts from copper smelting.

关键词： arsenic copper slag sequential extraction waste management copper smelting

Nucleation/growth mechanism of electrocrystallization for As-Sb alloy in hydrochloric acid system

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Transactions of Nonferrous Metals Society of China 2017年第10期27卷 2291-2299页

作者： Hua-zhen CAO Yu-feng ZHANG Qian-qian WANG Lian-kui WU guo-qu zheng College of Materials Science and Engineering Zhejiang University of Technology Hangzhou 310014 China

The initial electrocrystallization of As-Sb alloy on glass carbon(GC)electrode in hydrochloric acid system was studiedvia cyclic voltammetry(CV)and chronoamperometry *** transients were presented in dimensionless formation,which showed that the initial nucleation/growth process of As-Sb alloy followed three-dimensional nucleation model with *** nucleation parameters were calculated by analyzing related current *** attention waspaid to the effect of Sb(III)concentration on the nucleation process during the *** quantitative results showedthat Sb(III)played a positive effect on enhancing the nucleation rate of As-Sb alloy,leading to the evolution of alloy surfacemorphology from grain structure to compact layer structure.

关键词： arsenic antimony As-Sb alloy electrodeposition nucleation

Improving oxidation resistance of porous FeAl-based intermetallics with high boron/yttrium alloying

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Transactions of Nonferrous Metals Society of China 2022年第8期32卷 2620-2633页

作者： Hui-bin ZHANG Hang YU Jun-liang MA Long-fei WANG Sheng-hang XU guo-qu zheng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China

The coalloying with high contents of chromium(Cr),boron(B)and yttrium(Y)for porous B2-structured FeAl intermetallics fabricated through reactive synthesis was *** oxidation behaviors of porous FeAl-based materials were investigated by evaluating the pore-structure evolution,oxidation kinetics and oxide-scale *** results show that with the coalloying of high contents of Cr,B and Y,the oxidation mass gains of porous FeAl materials at 600−800℃ are significantly *** combination of B enriched on the surface of oxide scales and Y located at the scale−metal interface promotes the formation of thin protective nodularα-Al_(2)O_(3) oxide *** is indicated that introducing relatively high contents of reactive elements such as B and Y can benefit the selective growth ofα-Al_(2)O_(3) scales at relatively low temperatures without pre-treatment.

关键词： FeAl intermetallics yttrium high-temperature filter material oxidation porous material

Friction behavior of Ti-30Fe composites strengthened by TiC particles

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Transactions of Nonferrous Metals Society of China 2021年第4期31卷 988-998页

作者： Sheng-hang XU Jing-wen QIU Hui-bin ZHANG Hua-zhen CAO guo-qu zheng Yong LIU College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and TechnologyXiangtan 411201China

Ti-Fe-x TiC(x=0, 3, 6, 9, wt.%) composites were fabricated through low temperature ball milling of Ti, Fe and TiC powders, followed by spark plasma sintering. The results show that β-Ti, β-Ti-Fe, η-Ti4 Fe2 O0.4 and TiC particles can be found in the composites. The microstructure can be obviously refined with increasing the content of TiC particles. The coefficient of friction(COF) decreases and the hardness increases with increasing the content of TiC particles. The adhesive wear is the dominant wear mechanism of all the Ti-Fe-x TiC composites. The Ti-Fe-6 TiC composite shows the best wear resistance, owing to the small size and high content of TiC particle as well as relatively fine microstructure. The wear rate of the Ti-Fe-6 TiC composite is as low as 1.869× 10-5 mm3/(N·m) and the COF is only 0.64. Therefore, TiC particle reinforced Ti-Fe based composites may be utilized as potential wear resistant materials.

关键词： TiC particle Ti-Fe based composite powder metallurgy microstructure friction behavior

Composition and structure of arsenic−antimony alloy electrodeposited from acidic chloride solution

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Transactions of Nonferrous Metals Society of China 2021年第9期31卷 2861-2870页

作者： Yan-xiang SHU Hua-zhen CAO Hui-bin ZHANG Sheng-hang XU Guang-ya HOU Yi-ping TANG guo-qu zheng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China

AsSb alloy(0.70−95.81 wt.%As)was prepared by electrodeposition in As(III)and Sb(III)contained *** influence of electrolyte composition,hydrochloric acid concentration,and temperature on the composition and structure of AsSb deposits was *** electroreduction mechanism of As(III)and Sb(III)in hydrochloric acid solution was revealed via thermodynamic *** results show that the increase of H+concentration promotes the reduction of As(III),while the increase of Cl^(−)concentration significantly inhibits the reduction of Sb(III).As a result,the As content in deposits increases gradually with the increase of hydrochloric acid ***,the phase structure of AsSb deposits evolves from crystalline to *** the As content is 24.55−33.75 wt.%,AsSb mixed crystal is *** electrolysis temperature has little effect on the deposits composition,but the structure of deposits evolves from crystalline to amorphous with decreasing the temperature.

关键词： AsSb alloy composition phase structure hydrochloric acid thermodynamic analysis

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma Yang qu Jiaxin Ren Yingying Sun Zhen-Ni guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents