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An optimized sequential extraction scheme for molybdenum association in environmental samples

Acta Geochimica 2016年第2期35卷 111-119页

作者： Liang Liang jian-ming zhu State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 People's Republic of China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083China University of Chinese Academy of Sciences Beijing 100049People's Republic of China

By comparing three sequential extraction pro- cedures, a new optimized extraction scheme for the molyb- denum association in environmental samples was proposed. Five operational steps were described as exchangeable （KH2PO4 ＋ K2HPO4： including water-soluble）, associated with organic matter （NaOH）, Fe-Mn oxides and/or carbonates （HC1）, sulfides （H2O2） and residue （HNO3 ＋ HF ＋ H2O2）. An optimized extraction scheme was com- pared with Tessier＇s procedure and the Commission of European Communities Bureau of Reference （BCR） was applied to black shales. Results showed Tessier＇s procedure gave the lowest concentration values for exchangeable molybdenum and the highest values for the residual molybdenum, which could not present the efficiency of the extraction reagents. BCR＇s procedure showed the highest values in oxidizable molybdenum and presented four fractions of molybdenum, which did not demonstrate the fractions of molybdenum in the black shales in detail. The optimized extraction scheme demonstrated a certain improvement on extraction efficiency over Tessier＇s proce- dure for the lowest residual molybdenum, and revealed morefeatured fraction information of molybdenum in black shales than BCR＇ s. Therefore, after a comparison with other two extraction procedures, the optimized extraction scheme proved suitable for the molybdenum in black shales and it also showed an accurate determination of the molybdenum in the fractions and source of bioavailable Mo.

关键词： Molybdenum Sequential extractionprocedure Black shales

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Accurate and precise determination of lead isotope composition in selected geochemical reference materials

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Acta Geochimica 2017年第3期36卷 421-425页

作者： Guangliang Wu jian-ming zhu Decan Tan Guilin Han Lixing Zhang Kun Ren State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth Sciences China University of Geosciences Beijing 100083 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry CAS Guiyang 550081 China University of Chinese Academy of Sciences Beijing 100049China

Lead(Pb)isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the ***,Pb isotopic ratios in related geochemical reference materials are ***,we report high-precision Pb isotopic ratios measured by Nu Plasma II MC-ICP-MS using calibrated ^(205)Tl/^(203)Tl=2.38865(NIST SRM 997)for mass discrimination *** long-term external precision(2SD)for NISTSRM 981 of Pb,BCR-2,and BHVO-2 are 0.31‰(n=105),0.42‰(n=11),and 0.25‰(n=5)for ^(208)Pb/ ^(206)Pb and 0.16‰,0.53‰,and 0.07‰for ^(206)Pb/ ^(207)Pb,both respectively,and their Pb isotopic ratios are in excellent agreement with the recommended *** this method,we report for the first time Pb isotopic compositions in shale SGR-1b(USGS);coal CLB-1(USGS);stream sediments GSD-17,-21,and-23(IGGE);soils GSS-12,-13,-14,-15,and-16(IGGE);plants GSV-1,-2,and-3(IGGE);and human hair GSH-1(IGGE).

关键词： Lead isotopes Geochemical reference materials MC-ICP-MS

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Comparison of pharmacokinetics,efficacy and toxicity profile of gemcitabine using two different administration regimens in Chinese patients with non-small-cell lung cancer

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第5期8卷 307-313页

作者： WANG Lin-run LIU jian HUANG ming-zhu XU Nong Department of Clinical Pharmacy the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To conduct a randomized comparative trial of pharmacokinetics, efficacy and toxicity profile treatment with 1200 mg/m^2 gemcitabine using standard 30-min infusion or fixed dose rate （FDR） infusion [10 mg/（m^2-min）] on days 1 and 8 plus carboplatin AUC （area under curve） 5 on day 1 in Chinese non-small-cell cancer patients. Twelve patients were enrolled in this study. Methods： Plasma gemcitabine concentrations were measured by ion-pair reversed phase high performance liquid chromatography. Antitumoral activity and toxicity of gemcitabine was assessed according to World Health Organization criteria. Results： The obtained mean parameters, such as T1/2 （elimination half time）, AUC, and CL （clearance）, were consistent with those reported in literature. Qualified response rate in our study was 33.3% for standard arm and 50% for FDR ann. Additional 50% and 33.3% patients contracted stable disease （SD） in standard arm and FDR arm, respectively. The predominant toxicity was hematologic, and patients in the standard infusion ann experienced consistently more hematologic toxicity, Conclusion： Pharmacokinetic and clinical data in this trial support the continued evaluation of the FDR infusion strategy with gemcitabine.

关键词： Gemcitabine Non-small-cell lung cancer Pharmacokinetics Qualified response Safety

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A Heuristic Method for Temporal Analysis Based on Petri Net

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Wuhan University Journal of Natural Sciences 2002年第4期7卷 415-420页

作者： Fu jian-ming zhu Fu-xi Xiong Hui School of Computer Science Wuhan University Wuhan Hubei China

Reachability-based analysis and temporal analysis are used to verify the properties of concurrent systems, and it is important to exploit fast and efficient methods. This paper gives semantics of temporal formulae with edges of the transition system of Petri net, and then presents a fast temporal analyzing method, which takes advantage of both Petri net and temporal logic. The method only expands a path of equivalence trace while the path does not satisfy a property according to trace semantics of Petri net, and can validate directly the property on Petri net. Moreover, we exploit a minimal degree of in-out of a node as heuristics to select a path of an equivalence trace. Finally, we demonstrate the validity of the method that decreases state spaces and improves the verification system with the experimental results.

关键词： Petri net transition system temporal logic trace language

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Evaluation and selection of the ship collaborative design resources based on AHP and genetic and simulated annealing algorithm

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Journal of Marine Science and Application 2006年第1期5卷 23-30页

作者： HE Ze Qiu Chang-hua WANG Neng-jian YAO ming-zhu School of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China

The characteristics of the design resources in the ship collaborative design is described and the hierarchical model for the evaluation of the design resources is established. The comprehensive evaluation of the co-designers for the collaborative design resources has been done from different aspects using Analytic Hierarchy Process （AHP） ,and according to the evaluation results,the candidates are determined. Meanwhile,based on the principle of minimum cost,and starting from the relations between the design tasks and the corresponding co-designers,the optimizing selection model of the collaborators is established and one novel genetic combined with simulated annealing algorithm is proposed to realize the optimization. It overcomes the defects of the genetic algorithm which may lead to the premature convergenee and local optimization if used individually. Through the application of this method in the ship collaborative design system,it proves the feasibility and provides a quantitative method for the optimizing selection of the design resources.

关键词： ship collaborative design analytic hierarchy process genetic simulated anaealing algorithm resource evaluation resource selection

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Cadmium isotope compositions of Fe-Mn nodules and surrounding soils: Implications for tracing Cd sources

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Fundamental Research 2021年第3期1卷 269-276页

作者： Ting Gao Yuhui Liu Yafei Xia jian-ming zhu Zhengrong Wang Meng Qi Yizhang Liu Zengping Ning Qiqi Wu Wenpo Xu Chengshuai Liu State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Department of Earth&Atmospheric Sciences City College of New YorkCUNYNew York 10031United States National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China CAS Center for Excellence in Quaternary Science and Global Change Xi'an 710061China

Cadmium (Cd) pollution in agricultural soils has become a severe threat to food security and human health in recent years. Stable Cd isotopes are a potentially powerful tool for identifying the sources of Cd in soils. However, many Earth surface processes, including adsorption, leaching, and biogeochemical cycles in plants, may generate Cd isotope fractionation, which can complicate the potential application of Cd isotopes in tracing the sources of Cd pollution in soils. In this work, the Cd isotope compositions of typical Fe-Mn nodules (FMNs) and surrounding soils in two different soil profiles are investigated. Our results show that the FMNs in lower layers (i.e., C and W horizons) are isotopically lighter than the surrounding soils by –0.114‰ to –0.156‰ (Δ114/110CdFMN-soil). We interpret this fractionation as the result of preferential adsorption of isotopically light Cd onto the surface of goethite. In the upper layers (i.e., P and A horizons), the Δ114/110CdFMN-soil values are more negative in the P horizon (–0.213‰ to –0.388‰) but more positive in the A horizon (0.061‰ to 0.204‰). We interpret these fractionations as the result of natural biogeochemical processes (i.e., leaching and biological cycling) during soil development. Soil leaching preferentially releases isotopically heavy Cd into the underlying soil (i.e., P horizon), shifting the topsoil towards lower δ114/110Cd values but the underlying soils towards higher δ114/110Cd values. Moreover, biological cycling contributes isotopically heavy Cd to the topsoil, probably shifting the topsoil towards higher δ114/110Cd values. Our study demonstrates that the formation of Fe oxyhydroxides, leaching, and biological cycling can considerably modify the soil Cd isotope signature, highlighting the need to consider natural biogeochemical processes when using Cd isotopes to trace heavy metal pollution in soils.

关键词： Cadmium isotopes Fe-Mn nodules Leaching Biological cycling

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A Typical Megaesophagus： Interesting Imaging for Diagnosis

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Chinese Medical Journal 2015年第10期128卷 1418-1418页

作者： Shui-Bo zhu jian zhu ming Yan Yong Liu Department of Thoracic Cardiovascular Surgery Wuhan General Hospital of Guangzhou Command Wuhan I-lubei 430070 China

To the Editor： The dramatic expansion of an esophagus is extremely rare in esophageal diseases. We present a case of megaesophagus associated with atelectasis of the right lung, which showed a typical of achalasia with a “bird＇s beak appearance”. In order to palliate patient＇s symptoms, two gastric tubes used. One was inserted into the esophagus for suction residual chymus, the other was inserted into the stomach for supplying nutrition. However, after the symptoms eased, she refused all further treatment.

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MBER优化用于宽带功放通信系统

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北京邮电大学学报 2016年第6期39卷 37-41页

作者：楼建明朱仁祥郑悠钟秋波宁波工程学院电子与信息工程学院宁波315016 哈尔滨工业大学机器人技术与系统国家重点实验室哈尔滨150001

针对通信系统中宽带功率放大器引起的非线性失真问题,提出了最小差错概率(MBER)算法,以优化非线性均衡器参数,并采用非线性均衡器与数字预失真器对功率放大器非线性失真进行联合补偿.预失真用于减少非线性失真对带外的干扰,非线性均衡... 详细信息

针对通信系统中宽带功率放大器引起的非线性失真问题,提出了最小差错概率(MBER)算法,以优化非线性均衡器参数,并采用非线性均衡器与数字预失真器对功率放大器非线性失真进行联合补偿.预失真用于减少非线性失真对带外的干扰,非线性均衡器用于减少带内失真.仿真结果表明,基于MBER算法的非线性均衡器性能优于基于最小均方误差算法的均衡器;联合线性化简化了预失真器的结构,并可获得更优的误码率性能.

关键词：优化算法最小差错概率功率放大器非线性均衡器

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Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG jian NIE Wei HUANG Jin zhu Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

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Effects of glutamic acid on spontaneous discharges of arcuate nucleus in hypothalamic slice from normal and inflamed rats

Effects of glutamic acid on spontaneous discharges of arcuat...

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中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： jian-ming PENG,Qi zhu,Xing-Hong jianG Department of Neurobiology,Laboratory of Aging and Nervous Diseases,School of Medicine,Soochow University, Suzhou 215123,China

＜正＞To study the influence of glutamic acid（Glu） on the electric activities of arcuate nucleus（ARC） neurons in the normal rats and inflamed rats which were induced by complete Freund’s adjuvant（CFA）.The experiment was performed on isolated mediobasal hypothalamus slice to observe the effect of Glu on unit discharges of ARC *** NMDA receptor agonist NMDA,NMDA receptor antagonist MK-801 and non-NMDA receptor antagonist CNQX were used to analyze the receptor mechanism of *** unit discharges were recorded *** immunohistochemistry was imployed to observe the expression of NMDAR 1 in the ARC neurons of normal rats and the CFA *** experimental results indicated that:（1） Three types of spontaneous discharge（regular firing,irregular firing,firing in bursts） were observed in ARC neurons.（2） Glu（200μmol/L） can enhance the electric activities of ARC *** effects can be mimicried by NMDA（25 umol/L） and blocked by MK-801（100 umol/L）.（3） The spontaneous discharge frequency of ARC neurons in CFA rats was higher than those in normal rats.（4） The excitatory effects of Glu and NMDA in the ARC neurons of CFA rats were more *** spontaneous discharge frequency of ARC neurons incresed significantly,the latency of drug action was shortened and the duration was *** excitatory response of ARC neurons to Glu and NMDA couldn’t be blocked by CNQX but could be partly blocked by MK-801.（5） The results of immunohistochemistry indicated an up-regulation of the expression of NMDAR 1 in the ARC neurons of the CFA *** results suggested that glutamate mechanism（mediated by NMDA receptor） is involved in the modulation of the electric activities of ARC *** response of ARC neurons to glutamic acid is sensitized in CFA-inflamed rats.

关键词： glutamic acid(Glu) NMDA receptor MK-801 arcuate nucleus(ARC) brain slice inflammation central sensitization

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