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A Preliminary Study on Silver Isotopic Composition in Polymetallic Ore Deposits in Eastern China

Journal of Earth Science 2022年第1期33卷 100-108页

作者： Ge Dong hai-zhen Wei Yuanfeng zhu Xi Liu Qi Guo Wei Pu Yibo Lin Junlin Wang State Key Laboratory for Mineral Deposits Research Department of Earth Sciences and EngineeringNanjing University CAS Center for Excellence in Comparative Planetology

A preliminary survey of silver isotopic composition in four polymetallic ores in eastern China shows a larger variation inδ^(109)Ag from-0.014‰to+0.983‰,which is within the total ranges for the entire respective ore deposit types *** diversity of silver isotopic compositions in oredeposits reported here and previous studies seemed to preclude simple isotopic links to particular sources,but reflected the silver isotope fractionation in transport-and deposit-related processes ***δ^(109)Ag values in supergene samples from the Qixiashan Pb-Zn-Ag polymetallic deposit are more positive,in consistent with the statistical δ^(109)Ag distribution from-0.4‰to+2.2‰in 36 pieces of supergene ore samples around the World,which reflects the diverse controls on silver isotope fractionation from the first-order thermodynamic effect,reduction-mediated reaction,remobilization of silver with surficial low-temperature weathering *** hypogene samples in Dazhuangzi orogenic Au-Ag ore deposit,have δ^(109)Ag values close to 0,which implies that equilibrium partitioning associated with metal sources at the high-temperature does not result in a resolvable difference in silver isotopic *** contrast,the hypogene samples which are dominated by pyrite without visible silver minerals (i.e.,skarn iron ore deposit in Edongnan) have shown the largest variation range of δ^(109)Ag,followed by that from the porphyry copper ore in *** could be concluded that the surface adsorption and/or lattice substitution are important factors to control Ag isotope fractionation in oreforming processes,especially for skarn deposits with only *** perspective of silver isotope shows great potentials to understand the processes that lead to the concentrations of metals to economic levels and to constrain the physicochemical conditions during ore-mineralization in metallic ore-deposits.

关键词： silver isotopic composition hypogene ore deposits supergene ore deposits metal transport ore deposits

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Endogenous nitric oxide mediates alleviation of cadmium toxicity induced by calcium in rice seedlings

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Journal of Environmental Sciences 2012年第5期24卷 940-948页

作者： Long Zhang zhen Chen Cheng zhu State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310058China College of Life Sciences China Jiliang UniversityHangzhou 310018China School of Life Sciences Taizhou UniversityTaizhou 317000China

The effect of calcium chloride （CaCl2） on rice seedling growth under cadmium chloride （CdCl2） stress, as well as the possible role of endogenous nitric oxide （NO） in this process, was studied. The growth of rice seedlings was seriously inhibited by CdCl2, and the inhibition was significantly mitigated by CaCl2. However, hemoglobin （Hb） and 2-（4-carboxyphenyl）-4, 4,5,5-tetramethylimidazoline- l-oxyl-3-oxide （cPTIO） weakened the promotion effect of CaCl2. The results of NO fluorescence localization suggest that growth accelerated by CaCl2 might be associated with elevated NO levels. The content of Cd, protein thiols （PBT）, and nonprotein thiols （NPT） in cell walls, cell organelles, and soluble fractions, respectively, of rice seedlings decreased considerably in the presence of CaCl2, whereas the content of pectin, hemicellulose 1 （HC1）, and hemicellulose 2 （HC2） increased significantly. Elimination of endogenous NO in Cd＋Ca treatment could promote the transportation of Cd2＋ to cell organelles and soluble fractions and increase the content of NPT and PBT in leaves. In addition, transportation of Cd2＋ to cell organelles and soluble fractions was retarded in roots, the content of NPT increased, and the content of PBT decreased. With elimination of endogenous NO in Cd＋Ca treatment, the content of pectin, HC1, and HC2 decreased significantly. Thus, Ca may alleviate Cd toxicity via endogenous NO with variation in the levels of NPT, PBT, and matrix polysaccharides.

关键词： nitric oxide cadmium calcium nonprotein thiols protein thiols matrix polysaccharides

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Characterizations of precipitation behavior of Al-Mg-Si alloys under different heat treatments

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China Foundry 2018年第2期15卷 89-96页

作者： Hui Li Jia-yi Wang hai-tao Jiang zheng-feng Lu zhen-feng zhu College of Engineering Yantai Nanshan UniversityYantai 265700China Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center for Plastic Working of Alulinum Alloys Shandong Nanshan Aluminum Co.Ltd.Yantai 265713China

The solidification-precipitation behavior of Al-Mg-Si multicomponent alloys has long been an absorbing topic. Experiments were carried out to analyze the precipitation behaviors of Al-Mg-Si alloys under different heat treatments. All specimens were homogenized at 570 ℃ for 8 h, and then solution treated at 540 ℃ for 55 min. Subsequently, the specimens were age treated for different times at temperatures of 100 ℃, 150 ℃ and 180 ℃, respectively. The experimental results show that the occurrence of dispersed free zones （DFZ） is caused by the uneven distribution of dispersed phase. During the aging process, pre-β＂ phases form at the initial stage and an aging temperature of 100 ℃is too low to complete the transformation of pre-β＂ to β＂. At 150℃, the precipitation sequence is concluded as SSSS-pre-β＂-pre-β＂＋β＂-β＂-β＇-β. Moreover, changes in sizes and densities of the pre-β＂, β＂and β＇ phases during the aging process has an important influence on the evolution of microhardness and electrical resistivity. The microhardness peak value of 150 ℃ is similar to that of 180 ℃, which is -141 HV. While, at 100℃, the microhardness increases slowly, and the attainable value is 127 HV up to 19 days. When the aging temperature is 100 ℃, the electrical resistivity has the highest average value. When the aging temperature exceeds 100 ℃, with the occurrence and growth of β＂and β＇, the resistivity has a distinct decrease with prolonged aging time.

关键词： Al-Mg-Si alloy heat treatment precipitation behavior electrical resistivity

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Characteristics and roles of cytochrome b5 in cytochrome P450-mediated oxidative reactions in Locusta migratoria

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Journal of Integrative Agriculture 2020年第6期19卷 1512-1521页

作者： LIU Jiao ZHANG Xue-yao WU hai-hua MA Wen zhu Wen-ya Kun-Yan zhu MA En-bo ZHANG Jian-zhen Institute of Applied Biology Shanxi UniversityTaiyuan 030006P.R.China College of Life Science Shanxi UniversityTaiyuan 030006P.R.China Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006P.R.China Institute of Plant Protection Shanxi Academy of Agricultural SciencesTaiyuan 030031P.R.China Department of Entomology Kansas State UniversityManhattanKS 66506USA

Cytochrome b5(Cyt-b5)is a small heme protein and known to be involved in a wide range of biochemical transformations,in eluding cytochrome P450 monooxyge nase(CYP)-mediated metabolism of endoge nous and exogenous compo un *** on Cyt-b5 are more con centrated in mammals,but are relatively rare in in *** characteristics and functi on of Cyt-b5 from Locusta migratoria have not been described *** sequeneed the full-length cDNA sequenee of Cyt-b5 from ***(LmCyt-b5)by reverse transcription-PCR(RT-PCR)based on locust transcriptome *** phylogenetic analysis showed that LmCyt-b5 was closely related to the Cyt-b5 from ***-b5 was highly expressed in ovary,Malpighian tubules,midgut,gastric caeca,and fat *** of LmCyt-b5 had no effect on the susceptibility of *** to four different *** of LmCyt-b5 or silencing of both LmCyt-b5 and LmCPR did not significantly change the total CYP activity toward the substrate 7-ethoxycoumarin(7-EC).However,coexpression of LmCYP6FD1 with LmCPR and LmCyt-b5 together in Sf9 cells by using Bac-to-Bac baculovirus expression system significantly increased the catalytic activity of LmCYP6FD1 toward 7-EC as compared with the coexpression of ***6FD1 with cytochrome P450 reductase(LmCPR)or LmCyt-b5 *** results suggest that LmCyt-b5 plays an important role in the catalytic reaction of LmCYP6FD1 toward 7-EC in our in vitro *** study is needed to clarify the role of LmCyt-b5 in CYP-mediated catalytic reactions in ***.

关键词： cytochrome b5 cytochrome P450 cytochrome P450 reductase Locusta migratoria RNA interference

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Acute coronary syndrome with severe atherosclerotic and hyperthyroidism: A case report

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World Journal of Clinical Cases 2021年第27期9卷 8127-8134页

作者： hai-Mei zhu Yi Zhang Yun Tang Hua Yuan zhen-Xian Li Yun Long Department of Pain The First Hospital of Hunan University of Chinese MedicineChangsha 410007Hunan ProvinceChina The Graduate School Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Department of Cardiology The First Hospital of Hunan University of Chinese MedicineChangsha 410007Hunan ProvinceChina

BACKGROUND Acute coronary syndrome(ACS)encompasses a spectrum of cardiovascular emergencies arising from the obstruction of coronary artery blood flow and acute myocardial *** studies have revealed that thyroid function is closely related to ***,only a few reports of thyrotoxicosis-induced ACS with severe atherosclerosis have been *** SUMMARY A 33-year-old man,who had a history of hyperthyroidism without taking any antithyroid drugs and no history of coronary heart disease,experienced neck pain with occasional heart palpitations starting 3 mo prior that were aggravated after an *** the symptoms worsened at 21 d prior,he went to a hospital for *** electrocardiogram examination showed a multilead ST segment elevation and pathological Q *** on these findings and his symptoms,the patient was diagnosed with a suspected myocardial infarction and transferred to our hospital on July 2,*** was diagnosed with a rare case of ACS due to coronary artery atherosclerosis in the anterior descending artery complicated by hyperthyroidism.A paclitaxel-coated drug balloon was used for treatment to avoid the use of metal stents,thus reducing the time of antiplatelet therapy and facilitating the continued treatment of *** 9-mo follow-up showed favorable *** This case highlights that atherosclerosis is a cause of ACS that cannot be ignored even in a patient with hyperthyroidism.

关键词： Acute coronary syndrome Atherosclerosis Hyperthyroidism Paclitaxelcoated drug balloon Case report

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Non-uniform heat transfer behavior during shell solidification in a wide and thick slab continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 240-250页

作者： Zhao-zhen Cai Miao-yong zhu School of Materials and Metallurgy Northeastern University

By employing a two-dimensional transient thermo-mechanical coupled finite element model for simulating shell heat transfer behaviors within a slab continuous casting mold, we predicted the evolution of shell deformation and the thermal behaviors, including the mold flux film dynamical distribution, the air gap formation, as well as the shell temperature field and the growth of carbon steel solidification, in a 2120 mm × 266 mm slab continuous casting mold. The results show that the shell server deformation occurs in the off-corners in the middle and lower parts of the mold and thus causes the thick mold flux film and air gap to distribute primarily in the regions of 0–140 mm and 0–124 mm and 0–18 mm and 0–10 mm, respectively, from the corners of the wide and narrow faces of the shell under typical casting conditions. As a result, the hot spots, which result from the thick mold flux film filling the shell/mold gap, form in the regions of 20–100 mm from the corners of the wide and narrow faces of the shell and tend to expand as the shell moves downward.

关键词： continuous casting molds heat transfer solidification finite element method

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An entirely new approach based on remote sensing data to calculate the nitrogen nutrition index of winter wheat

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Journal of Integrative Agriculture 2021年第9期20卷 2535-2551页

作者： ZHAO Yu WANG Jian-wen CHEN Li-ping FU Yuan-yuan zhu Hong-chun FENG hai-kuan XU Xin-gang LI zhen-hai Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs/Beijing Research Center for Information Technology in Agriculture Beijing 100097P.R.China National Engineering Research Center for Information Technology in Agriculture Beijing 100097P.R.China College of Geomatics Shandong University of Science and TechnologyQingdao 266590P.R.China

The nitrogen nutrition index(NNI)is a reliable indicator for diagnosing crop nitrogen(N)***,there is currently no specific vegetation index for the NNI inversion across multiple growth *** overcome the limitations of the traditional direct NNI inversion method(NNI_(T1))of the vegetation index and traditional indirect NNI inversion method(NNI_(T2))by inverting intermediate variables including the aboveground dry biomass(AGB)and plant N concentration(PNC),this study proposed a new NNI remote sensing index(NNI_(RS)).A remote-sensing-based critical N dilution curve(Nc_(_RS))was set up directly from two vegetation indices and then used to calculate NNI_(RS).Field data including AGB,PNC,and canopy hyperspectral data were collected over four growing seasons(2012–2013(Exp.1),2013–2014(Exp.2),2014–2015(Exp.3),2015–2016(Exp.4))in Beijing,*** experimental datasets were cross-validated to each of the NNI models(NNI_(T1),NNI_(T2)and NNI_(RS)).The results showed that:(1)the NNI_(RS)models were represented by the standardized leaf area index determining index(sLAIDI)and the red-edge chlorophyll index(CI_(red edge))in the form of NNI_(RS)=CI_(red edge)/(a×sLAIDI~b),where"a"equals 2.06,2.10,2.08 and 2.02 and"b"equals 0.66,0.73,0.67 and 0.62 when the modeling set data came from Exp.1/2/4,Exp.1/2/3,Exp.1/3/4,and Exp.2/3/4,respectively;(2)the NNI_(RS)models achieved better performance than the other two NNI revised methods,and the ranges of R2 and RMSE were 0.50–0.82 and 0.12–0.14,respectively;(3)when the remaining data were used for verification,the NNI_(RS)models also showed good stability,with RMSE values of 0.09,0.18,0.13 and 0.10,***,it is concluded that the NNI_(RS)method is promising for the remote assessment of crop N status.

关键词： nitrogen nutrition index(NNI) critical nitrogen dilution curve standardized leaf area index determining index(s LAIDI) the red-edge chlorophyll index(CI_(red edge))

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Sheet Bulk Forming of Thin-Walled Components with External Gearing through Upsetting Using Controllable Deformation Zone Method

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 282-295页

作者： Xincun zhuang Meile Liang Shengfa zhu Yin zhu zhen Zhao Institute of Forming Technology and Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200030China National Engineering Research Center of Die&Mold CAD Shanghai Jiao Tong UniversityShanghai 200030China

Sheet-bulk metal forming(SBMF)is a promising process for manufacturing complex sheet components with functional *** this study,the entire forming process for a typical thin-walled component with external gearing is investigated,including sheet forming and bulk forming *** drawn cups are prepared during sheet forming;subsequently,upsetting is performed on the sidewall to form external *** upsetting method performed is known as upsetting with a controllable deformation zone(U-CDZ).Compared with the conventional upsetting method,a floating counter punch with a counter force is used in the U-CDZ method such that the forming mechanism is changed into the accumulation of the deformation zone instead of deformation throughout the entire *** effects of the counter force and material flow are investigated to understand the *** forming quality,i.e.,the formfilling and effective strain distribution,improved,whereas a high forming load is *** addition,a punch with a lock bead is used to prevent folding at the inner corner during the experiment.

关键词： Sheet-bulk metal forming Thin-walled components External gearing Controllable deformation zone

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From blocker to booster:Harnessing garnet surface chemistry for advanced solid-state electrolytes

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Nano Research 2025年第1期18卷 323-331页

作者： Jun Cheng Xuan Zhou Hongqiang Zhang zhen Zeng Yuanyuan Li Yulong zhu Yingsheng Liao Lijie Ci Deping Li State Key Laboratory of Precision Welding and Joining of Materials and Structures School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China

Garnet electrolytes with high ionic conductivity and electrochemical stability are widely used as fillers to fabricate composite solid electrolytes(CPEs)within polymer ***,the performance of CPEs is significantly influenced by the surface characteristics of the garnet ***,the impact of garnet surface characteristics on CPEs was systematically investigated and a conversion from a typically unstable and Lewis basic surface to a more stable Lewis acidic surface was realized,which is shown to be more conductive to the improved performance of *** simultaneously removing the Li_(2)CO_(3)layer and applying a Li-Al-O coating,the influence of surface characteristics on CPEs was *** Lewis acid Li-Al-O surface coating not only promotes lithium salt dissociation,improving the ionic conductivity and ionic transfer number,but also prevents the reformation of the passive Lewis basic Li_(2)CO_(3)*** to garnet with a Lewis basic Li_(2)CO_(3)surface,the garnet modified with a Lewis acid Li-Al-O coating enhances CPEs,which exhibit an improved critical current density of 1.0 mA·cm^(-2)and highly stable lithium symmetric cell cycling for 400 h at 0.2 mA·cm^(-2).This research highlights the importance of surface chemistry in the design of high-performance solid-state batteries and presents a strategic modification approach for garnetbased CPEs.

关键词： garnet electrolyte composite solid electrolyte surface chemistry all-solid-state batteries

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Antibacterial activity and mechanism of newly developed Zr-30Ta and Zr-25Ta-5Ti alloys against implant-associated infection

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Rare Metals 2022年第12期41卷 4176-4187页

作者： hai-Lin Yang Akram Nasser Juaim Ling Zou Meng-zhen zhu Xiao-Na Chen Chen-Xu Ma Xiong-Wen Zhou State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China Department of Prosthodontics Center of StomatologyXiangya HospitalCentral South UniversityChangsha 410008China Department of Prosthodontics Faculty of DentistryThamar UniversityDharmarYemen Department of Oral Implantology Xiangya Stomatological Hospital and School of StomatologyCentral South UniversityChangsha 410008China

Infection is a common problem after implantation,and the currently used Ti-based implants have insufficient antibacterial *** newly developed Zr-30Ta and Zr-25Ta-5Ti alloys exhibited good mechanical properties,low elastic moduli,and high corrosion *** this work,their antibacterial activities and antibacterial mechanisms were *** surface roughness,wettability,and charge of the alloys were evaluated using a profilometer,drop shape analyzer,and electrokinetic analyzer,*** antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis was investigated using the inhibition zone assay,plate count assay,live/dead staining,and scanning electron microscopy(SEM).The reactive oxygen species release(ROS)was evaluated using the 2’7’-dichlorodihydrofluorescein diacetate(DCFH-DA)*** results demonstrated that Zr-30Ta and Zr-25Ta-5Ti alloys had favorable smooth,hydrophilic,negatively charged surfaces that decreased bacteria adhesion and prevented biofilm ***-30Ta and Zr-25Ta-5Ti alloys also exhibited a time-dependent decrease in the bacteria adhesion and ***-30Ta and Zr-25Ta-5Ti alloys were also found to induce direct membrane damage and increase ROS production,resulting in significantly better antibacterial activities than ***-30Ta and Zr-25Ta-5Ti alloys exhibited comparable antibacterial *** work suggests that the newly developed Zr-30Ta and Zr-25Ta-5Ti alloys have good antibacterial activity against Streptococcus mutans and Porphyromonas gingivalis and are promising candidate materials for dental and orthopedic implants.

关键词： Zirconium-tantalum Dental implant Antibacterial Peri-implant infection Biofilm

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