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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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Studies of the Intramolecular Aromatic-ring Stacking Interactions in the Ternary Platinum(Ⅱ) Complexes

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Chemical Research in Chinese Universities 2005年第1期21卷 8-11页

作者： SUNHong-liang ResearchCenterofChemistry＆Analysis ZhejiangGongshangUniversityHangzhou310035P.R.China

The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.

关键词： Platinum(Ⅱ) Mixed-ligand complex Aromatic-ring stacking Stability constant

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Global existence and large-time behavior for primitive equations with the free boundary

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Science China Mathematics 2024年第10期67卷 2303-2330页

作者： Hai-liang Li Chuangchuang liang School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing 100048China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In the present paper, the primitive equations, which can be used to simulate the large-scale motion of the ocean and atmosphere, are considered in the three-dimensional domain bounded below by a fixed solid boundary and above by a free-moving boundary. The global existence and uniqueness of strong solutions are established, and the long-time convergence to the equilibrium state is shown to be either at an exponential rate for the horizontal periodic domain or at an algebraic rate for the horizontal whole space.

关键词： primitive equations the free boundary value problem global well-posedness large-time behavior

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Relationship between powder characteristic and internal oxidation of Al in Cu-Al pre-alloyed powders

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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 71-80页

作者： Shuhua liang Xianhui WANG liang FANG Zhikang FAN Department of Materials Science and Engineering Xi＇an University of Technology Xi＇an 710048 China State Key Laboratory for Mechanical Behavior of Materials Xi＇an Jiaotong University Xi＇an 710049 China

Since Cu-Al powder characteristics have important effects on the preparation of Cu/Al2O3 composite, the apparent activation energy of Al internal oxidation reaction in Cu-Al pre-alloyed powders with different characteristics was calculated in the present investigation. The microstructure and properties of the synthesized Cu/Al2O3 were studied. The results show that high-energy milling can obviously promote internal oxidation of Al in Cu-Al powders in the same solid solubility. At the same milling conditions and internal oxidation parameters, the solid solution of Al in Cu either in low or high amount will result in the poor microstructure and properties of the Cu/Al2O3 composite. Subsequently, when high-energy milling and internal oxidation are synchronously used to prepare the Cu/Al2O3 composite, there should be an appropriate solubility and milling effect for the pre-alloyed powders.

关键词： Powder characteristic Internal oxidation Cu/Al2O3 composite material Solid solution Reaction rate

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On d-row(Column) Antimagic Matrices and Subset Partitions

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 192-200页

作者： Zhi-he liang Shi-xin liang School of Mathematical Science Hebei Normal UniversityShijiazhuang 050024China ABB Electric Transmission Systems Co.LTD Beijing 100020China

An m×k matrix is said to be a d-row(column)antimagic matrix if its row-sums(column-sums)form an arithmetic progression with a difference *** goal of this paper is to obtain the existence theorems and construction methods of some d-row(column)antimagic *** these results we give the necessary and sufficient condition for the existence of an(m,d)-partition of[1,mk].

关键词： matrix d-row(column)antimagic matrix subset partition

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Advances in Understanding Cadmium Stress and Breeding of Cadmium-Tolerant Crops

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Rice science 2024年第5期31卷 507-525页

作者： liang liang WANG Chenchang CHEN Tao School of Life and Environmental Science Hangzhou Normal UniversityHangzhou 311121China

Cadmium(Cd) pollution has emerged as a critical global environmental concern, due to its significant toxicity, environmental persistence, and the pervasiveness of contamination. Significantly, the bioaccumulation of Cd in agricultural crops constitutes a primary vector for its entry into the human diet. This issue warrants urgent attention from both the scientific community and policymakers to develop and implement effective mitigation strategies. This review delves into the physiological impacts of Cd stress on plants, including the suppression of photosynthetic activity, amplification of oxidative stress, and disruptions in mineral nutrient homeostasis. Additionally, the resistance mechanisms deployed by plants in response to Cd stress have been explored, and the prospective contributions of molecular breeding strategies in augmenting crop tolerance to Cd and minimizing its bioaccumulation have been assessed. By integrating and analyzing these findings, we seek to inform future research trajectories and proffer strategic approaches to enhance agricultural sustainability, safeguard human health, and protect environmental integrity.

关键词： cadmium stress crop tolerance physiological response molecular breeding strategy

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Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing FANG Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

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Complex Tanh-Function Expansion Method and Exact Solutions to Two Systems of Nonlinear Wave Equations

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Communications in Theoretical Physics 2004年第4X期42卷 491-493页

作者： ZHANGJin-liang WANGMing-liang DepartmentofMathematicsandPhysics HenanUniversityofScienceandTechnologyLuoyang471003China

The complex tanh-function expansion method was presented recently, and it can be applied to derive exact solutions to the Schrodinger-type nonlinear evolution equations directly without transformation. In this paper,the complex tanh-function expansion method is applied to derive the exact solutions to the general coupled nonlinear evolution equations. Zakharov system and a long-short-wave interaction system are considered as examples, and the new applications of the complex tanh-function expansion method are shown.

关键词：复合双正切函数展开长短波相互作用系统精确解非线性波函数量子力学薛定谔方程

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A RANKING METHOD FOR DMUS WITH INTERVAL DATA BASED ON DEA CROSS-EFFICIENCY EVALUATION AND TOPSIS

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Journal of Systems Science and Systems Engineering 2013年第2期22卷 191-201页

作者： Jie WU Jiasen SUN Malin SONG liang liang School of Management University of Science & Technology of China

The traditional data envelopment analysis （DEA） model can evaluate the relative efficiencies of a set of decision making units （DMUs） with exact values of inputs and outputs, but it cannot handle imprecise data. Imprecise data, for example, can be expressed in the form of the interval data or mixtures of interval data and ordinal data. In this study, a cross-efficiency method is introduced into the DEA model to calculate the interval of cross-efficiency values, based on which a new TOPSIS method is proposed to rank the DMUs. Two examples are presented to illustrate and validate the proposed method.

关键词： Data envelopment analysis (DEA) cross-efficiency TOPSIS

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HNF-4α determines hepatic differentiation of human mesenchymal stem cells from bone marrow

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World Journal of Gastroenterology 2010年第40期16卷 5092-5103页

作者： Mong-liang Chen Kuan-der Lee Huei-Chun Huang Yue-Lin Tsai Yi-Chieh Wu Tzer-Min Kuo Cheng-Po Hu Chungming Chang Division of Molecular and Genomic Medicine National Health Research Institutes Department of Hematology and Oncology Chang Gung Memorial Hospital Institute of Microbiology and Immunology National Yang-Ming University Department of Life Science Tunghai University

AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induced into hepatocyte-like cells following a previously published protocol. The differentiation status of the hepatocyte-like cells was compared with various human hepatoma cell lines. Overexpression of hepatocyte nuclear factor (HNF)-4α was mediated by adenovirus infection of these hepatocyte-like cells. The expression of interesting genes was then examined by either re-verse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that the differentiation status of hepatocyte-like cells induced from human MSCs was relatively similar to poorly differentiated human hepatoma cell lines. Interestingly, the HNF-4 isoform in induced MSCs and poorly differentiated human hepatoma cell lines was identified as HNF4γ instead of HNF-4α. Overexpression of HNF-4α in induced MSCs significantly enhanced the expression level of hepatic-specific genes, liver-enriched transcription factors, and cytochrome P450 (P450) genes. CONCLUSION: Overexpression of HNF-4α improves the hepatic differentiation of human MSCs from bone marrow and is a simple way of providing better cell sources for clinical applications.

关键词： Bone marrow Cytochrome P450 genes Differentiation of hepatocyte Hepatocyte nuclear factor 4 Human mesenchymal stem cells

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