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Leaching of vanadium,sodium,and silicon from molten V?Ti-bearing slag obtained from low-grade vanadium-bearing titanomagnetite

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 898-905页

作者： yuan-yuan zhu University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The water leaching process of vanadium, sodium, and silicon from molten vanadium-titanium-bearing（V-Ti-bearing） slag obtained from low-grade vanadium-bearing titanomagnetite was investigated systematically. The results show that calcium titanate, sodium aluminosilicate, sodium oxide, silicon dioxide and sodium vanadate are the major components of the molten V-Ti-bearing slag. The experimental results indicate that the liquid-solid（L/S） mass ratio significantly affects the leaching process because of the respective solubilities and diffusion rates of the components. A total of 83.8% of vanadium, 72.8% of sodium, and 16.1% of silicon can be leached out via a triple counter-current leaching process under the optimal conditions of a particle size below 0.074 mm, a temperature of 90°C, a leaching time of 20 min, an L/S mass ratio of 4：1, and a stirring speed of 300 r/min. The kinetics of vanadium leaching is well described by an internal diffusion-controlled model and the apparent activation energy is 11.1 kJ/mol. The leaching mechanism of vanadium was also analyzed.

关键词： titanomagnetite vanadium metallurgy leaching kinetics sodium silicon leaching rate

Synthesis of Polyphosphonates Containing 5-Flouro-N^1-furanyl-N^3-glyceroalkyl-uracil and Formyl Groups

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Chinese Chemical Letters 2002年第1期13卷 29-32页

作者： Li BAI Ru Yu CHEN yuan yuan zhu Institute and National Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071

A series of novel polyphosphonates containing 5-flouro- N1-furanyl-N3- glyceroalkyl-uracil and formyl groups was synthesized by the condensation of 3-(w- (1-furanyl-5-flourouracil-3-yl) alkoxy)-1, 2-dihydroxy propane with phosphonyl dichloride. The products were characterized by IR, 1H NMR, 31P NMR, M, and elemental analysis. The results of bioassay show that compound 8a possesses potential anticancer activity.

关键词： Polyphosphates furanyl,glyceryl 5-flourouracil formyl.

Electron Transport Behavior of Multiferroic Perovskite BiMnO_3 Prepared by Co-Precipitation Method

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Chinese Physics Letters 2018年第2期35卷 84-87页

作者： Hong-Jun Wang yuan-yuan zhu Jing Zhou Department of Physics Shaanxi University of Science and Technology

Perovskite BiMnO_3 samples are successfully synthesized by the co-precipitation method at relatively low pressure and moderate *** temperature dependences of resistivity are measured and systematically *** is shown that the electrical resistivity increases sharply with the decrease of temperature above 210 K and the fitted results demonstrate that the thermally activated conduction model is the dominant conduction mechanism for the electron transport behaviors in this temperature region.A dual conducting mechanism,i.e.,the variable range hopping and thermal activated conduction,is suggested to be responsible for the transport behaviors of BiMnO_3 in the region of 180-200 ***,the resistivity increases slightly with the decrease of temperature below 180 K and the transport is governed by the variable range hopping mechanism.

关键词： Bi Electron Transport Behavior of Multiferroic Perovskite BiMnO3 Prepared by Co-Precipitation Method

Optically Active Helical Polyisocyanides Bearing Chiral Phosphine Pendants: Facile Synthesis and Application in Enantioselective Rauhut-Currier Reaction

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Chinese Journal of Polymer Science 2018年第2期36卷 163-170页

作者： Li Zhou Ling Shen Jian Huang Na Liu yuan-yuan zhu Zong-Quan Wu Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering and Anhui Key Laboratory of Advanced Catalytic Materials and Reaction Engineering Hefei University of Technology School of Material and Chemical Engineering Bengbu University

Three novel enantiopure phenyl isocyanide monomers with BH3-protected phosphine functional group were designed and synthesized. Polymerization of these monomers using a alkyne-Pd（II） complex as a catalyst led to the formation of respective helical polyisocyanides in high yields with controlled molecular weights（Mns） and narrow molecular weight distributions（Mw/Mns）. Removing the protecting BH3 groups afforded helical poly（phenyl isocyanide）s bearing phosphine pendants. Thanks to the chiral induction of monomer, the isolated helical polyisocyanides showed high optical activity, as revealed by circular dichroism（CD） and absorption spectroscopies and polarimetry. The helical structures of these polymers were quite stable in various organic solvents with different polarities and in a wide temperature range. Moreover, these helical polymers could be used as organocatalysts and showed good performance in enantioselective cross Rauhut-Currier reaction. The enantiomeric excess（ee） values of the isolated products of cross Rauhut-Currier reaction could be up to 90%. The polymer organocatalysts could be easily recovered from the reaction mixtures and reused at least five times in the reaction without significant loss of their enantioselectivities and catalytic activities.

关键词： Helical polymer Polyisocyanide Coordination polymerization Polymer catalyst

TSPAN1 protein expression:A significant prognostic indicator for patients with colorectal adenocarcinoma

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World Journal of Gastroenterology 2009年第18期15卷 2270-2276页

作者： Li Chen yuan-yuan zhu Xiao-Juan Zhang Gui-Lan Wang Xin-Yu Li Song He Jian-Bin Zhang Jian-Wei zhu Department of Pathological Anatomy Nantong University Nantong 226001Jiangsu Province China Biomics (Nantong) Co. Ltd Nantong226016 Jiangsu Province China Department of Pathology The Second Affiliated Hospital Nantong University Nantong 226001Jiangsu Province China Department of Pathology The Affiliated Tumor Hospital Nantong University Nantong226361 Jiangsu Province China Department of General Surgery Affiliated Hospital Nantong University Nantong 226001 Jiangsu Province China

AIM:To determine if TSPAN1 overexpression is associated with clinicopathological and prognostic factors in human colorectal ***:Total RNA was extracted in 20 human adenocarcinoma tissues for TSPAN1 mRNA assay by ***-eight specimens of human colorectal adenocarcinoma were surgically ***1 protein levels in cancer tissues were determined by immunohistochemistry using a polyclonal antibody against self-prepared *** correlation between TSPAN1 expression and the clinicopathological factors and the overall survival rate was analyzed by univariate and multivariate ***:TSPAN1 mRNA was detected in 90.0%(18/20) of cancerous *** light density of TSPAN1 mRNA expression levels was 0.89 ± 0.30 in adenocarcinoma by gel-image ***1 protein expression was detected in 78.41%(69/88) and weakly expressed in 40% normal colorectal *** were significant differences between colorectal adenocarcinoma and normal control epithelium(P < 0.05).TSPAN1 protein expression in colorectal cancerous tissue was significantly correlated with the histological grade,cell expression PCNA,lymph nodal metastasis and TNM staging of the *** with TSPAN1 protein overexpression had a significantly shorter survival period than that in patients with TSPAN1 protein negative or weak expression,respectively(P < 0.05).Furthermore,by multivariate analysis,TSPAN1 protein expression demonstrated an independent prognostic factor for human colorectal cancers(P < 0.05,relative risk 0.755;95% confidence interval 0.302-1.208).CONCLUSION:The expression of TSPAN1 gene is increased in colorectal carcinoma,suggesting that TSPAN1 might serve as an independent prognostic factor for the colorectal adenocarcinoma patients.

关键词： TSPAN1 Colorectal adenocarcinoma Semi-quantitative RT-PCR immunohistochemistry Prognosis

Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures

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Journal of Materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingfeng Zou Lifeng Ma Yanchun zhu Ling Qin yuan yuan School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy Machinery Engineering Research Center of the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility,which is urgently needed in the fundamental science of engineering *** this study,heterogeneous structures of AZ61 alloy bars with anisotropic gradients(with different grain size distributions from the surface to the center)were observed to exhibit strong strength-ductility synergies under different deformation tem *** results reveal that the grain refinement process under mediumlow temperature deformation conditions(≤350℃)consists of four transition stages along the radial direction,i.e.,twin activations and deformation band formations,dislocation cells and pile-ups,ultrafine sub-grains,and randomly orientated quasi-micron *** deformation temperatures have a great influence on twin activations and deformation band formations,and the high temperature can easily provoke the initiation of non-basal *** deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial forging(RF)deformation process,the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different tem *** summarizing the tensile test results,the sample forged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of 23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial forging Strength-ductility synergy Magnesium alloy Strengthening mechanism

Synthesis of novel chalcone derivatives and their stabilization effect of spiropyran in PMMA films

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Chinese Chemical Letters 2011年第9期22卷 1025-1028页

作者： Zheng Kai Si Qing Zhang Min Zhao Xue yuan yuan zhu Liang Ming Qiao Rong Sheng Yan Gang Liu School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 China

Three novel bis-chalcone derivatives with different alkyldioxy spacers were synthesized and dispersed into polymethyl methacrylate （PMMA） chloroform solution with 6-nitro-1＇-ethyl-3＇,3＇-dimethylspiro-2H-1-benzopyran-2,U-indoline （ESP） to prepare photochromic PMMA films in a facile way. After irradiation with 365 nm UV light, the photocrosslinking reaction between chalcone units was proved to retard the decolorization of merocyanine form of the photochromic spiropyran effectively, as results of the steric hindrance produced by photocycloaddition of chalcone groups. It has been found that the bis-chalcone molecule with the shortest spacer has the most effective stabilizing effect on retardation of decoloration of spiropyran. reserved.

关键词： Photochromism Chalcone Spiropyran Photocycloaddition Slabilization effect

Numerical investigation of the photo-thermal characteristics of a direct absorption solar collector using Monte Carlo and finite volume methods

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Science China(Technological Sciences) 2024年第8期67卷 2436-2448页

作者： zhu YanLong LI SuNing FAN JianHua KONG WeiQiang yuan yuan TAN HePing School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Civil Engineering and Mechanical Engineering Technical University of DenmarkKoppels AlléBuilding 4042800 Kgs.LyngbyDenmark School of Vehicle and Energy Yanshan UniversityQinhuangdao 066004China

In this study, a novel model of photothermal conversion in a direct absorption solar collector based on the Monte Carlo and finite volume methods was built and validated and the temperatures of the novel and traditional solar collectors were compared. The sensitivity of the parameters to the radiative heat loss was investigated. Finally, the radiative heat transfer characteristics were discussed using the radiative exchange factor. The results of this study validated the advantages of the novel solar collector at both the surface and fluid temperatures. Under the conditions used in this study, the maximum temperature difference of the novel solar collector was 30 K, compared with 193 K for the traditional solar collector. Furthermore, the collector was divided into several units along the flow direction. The radiative exchange factor indicated that with an increase in the attenuation coefficient, the percentage of radiation intensity in the total solar radiation absorbed by the corresponding unit ***, it decreased with an increase in the incident angle and scattering albedo. These results provide a reference for addressing the low efficiency and thermal damage caused by traditional solar collectors at high temperatures.

关键词： direct absorption solar collector radiative heat transfer Monte Carlo

New Staudinger Strategy Enabled N-Acyl Phosphinamidites Synthesis

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CCS Chemistry 2022年第4期4卷 1397-1404页

作者： yuan-yuan zhu Gang-Wei Wang Jin Yang Shang-Dong Yang State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000 State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000

A new Staudinger strategy entails a unique C-P bond cleavage,instead of N-P bond cleavage,during the construction of N-acyl phosphinamidites by using acyl-phosphine *** reaction is performed under very mild conditions,with no need for additional catalysts or additives,and thus preserves stereogenic centers that are sensitive to epimerization.A range of novel N-acyl phosphinamidites,including those bearing a chiral amino acid skeleton and axial chirality as well as complex natural product scaffolds,were produced with N_(2) gas as the only *** N-acyl phosphinamidites are potential novel P-O ligands,and preliminary screening results have demonstrated their application as chiral organic catalysts.

关键词： N-acyl phosphinamidites azide insertion catalyst-and base-free C-P bond cleavage 1,2-acyl migration