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Science China Chemistry 2008年第7期51卷 661-668页

作者： WANG JunHua liu Lang liu GuangFei GUO JiXi JIA DianZeng Institute of Applied Chemistry Xinjiang UniversityUrumqi 830046China

Three new photoisomeric compounds: 1,3-diphenyl-4-benzal-5-pyrazolone 4-methylthiosemicarbazone (DPBP-MTSC), 1,3-diphenyl-4-(4′-methylbenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4MBP- MTSC), and 1,3-diphenyl-4-(4′-bromobenzal)-5-pyrazolone 4-methylthiosemicarbazone (DP4BrBP-MTSC) were synthesized by direct condensation of pyrazolones and 4-methylthiosemicarbazone. Their struc- tures were confirmed using 1H NMR, IR, elemental analyses, and X-ray crystallographic analyses. The photoisomeric properties in the solid state were studied under UV light irradiation and the photo- isomerization phenomena were interpreted by the double proton-transfer mechanism. Moreover, the effects of different substituent groups at the 4-position of the benzal in the three compounds on the photoisomeric properties were discussed.

关键词： photoisomerization pyrazolone proton-transfer substitute effects

Fracture toughness and fracture behavior of SA508-Ⅲ steel at different temperatures

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International Journal of Minerals,Metallurgy and Materials 2014年第12期21卷 1187-1195页

作者： Jia-hua liu Lei Wang Yang liu Xiu Song Jiong Luo Dan Yuan Key Laboratory for Anisotropy and Texture of Materials Northeastern University

The fracture toughness of SA508-Ⅲ steel was studied in the temperature range from room temperature to 320℃ using the J-integral method. The fracture behavior of the steel was also investigated. It was found that the conditional fracture toughness （JQ） of the steel first decreased and then increased with increasing test temperature. The maximum and minimum values of do were 517.4 kJ/m^2 at 25℃ and 304.5 kJ/m^2 at 180℃, respectively. Dynamic strain aging （DSA） was also observed to occur when the temperature exceeded 260℃ with a certain strain rate. Both the dislocation density and the number of small dislocation cells effectively increased because of the occurrence of DSA; as a consequence, crack propagation was more strongly inhibited in the steel. Simultaneously, an increasing number of fine carbides precipitated under high stress at temperatures greater than 260℃. Thus, the deformation resistance of the steel was improved and the Jo was enhanced.

关键词： low alloyed steel fracture toughness fracture behavior temperature dynamic strain aging nuclear power plants

PXR activation impairs hepatic glucose metabolism partly via inhibiting the HNF4α-GLUT2 pathway

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Acta Pharmaceutica Sinica B 2022年第5期12卷 2391-2405页

作者： Peihua liu Ling Jiang Weimin Kong Qiushi Xie Ping Li Xiaonan liu Jiayi Zhang Ming liu Zhongjian Wang Liang Zhu Hanyu Yang Ying Zhou Jianjun Zou Xiaodong liu Li liu Center of Drug Metabolism and Pharmacokinetics School of PharmacyChina Pharmaceutical UniversityNanjing 210009China Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy Xuzhou Medical UniversityXuzhou 221004China Department of Clinical Pharmacology Nanjing First HospitalNanjing Medical UniversityNanjing 210006China

Drug-induced hyperglycemia/diabetes is a global issue. Some drugs induce hyperglycemia by activating the pregnane X receptor(PXR), but the mechanism is unclear. Here, we report that PXR activation induces hyperglycemia by impairing hepatic glucose metabolism due to inhibition of the hepatocyte nuclear factor 4-alpha(HNF4 a)-glucose transporter 2(GLUT2) pathway. The PXR agonists atorvastatin and rifampicin significantly downregulated GLUT2 and HNF4 a expression, and impaired glucose uptake and utilization in HepG2 cells. Overexpression of PXR downregulated GLUT2 and HNF4 a expression, while silencing PXR upregulated HNF4 a and GLUT2 *** HNF4 a decreased GLUT2 expression, while overexpressing HNF4 a increased GLUT2 expression and glucose uptake. Silencing PXR or overexpressing HNF4 a reversed the atorvastatininduced decrease in GLUT2 expression and glucose uptake. In human primary hepatocytes, atorvastatin downregulated GLUT2 and HNF4 a mRNA expression, which could be attenuated by silencing PXR. Silencing HNF4 a downregulated GLUT2 mRNA expression. These findings were reproduced with mouse primary hepatocytes. Hnf4 a plasmid increased Slc2 a2 promoter activity. Hnf4 a silencing or pregnenolone-16 a-carbonitrile(PCN) suppressed the Slc2 a2 promoter activity by decreasing HNF4 a recruitment to the Slc2 a2 promoter. Liver-specific Hnf4 a deletion and PCN impaired glucose tolerance and hepatic glucose uptake, and decreased the expression of hepatic HNF4 a and GLUT2. In conclusion, PXR activation impaired hepatic glucose metabolism partly by inhibiting the HNF4 aGLUT2 pathway. These results highlight the molecular mechanisms by which PXR activators induce hyperglycemia/diabetes.

关键词： Pregnane X receptor Hepatocyte nuclear factor4-alpha Glucose transporter 2 Hepatic glucose uptake Diabetes Drug-induced hyperglycemia

Tilted Angle Implantation of Xe Ions in potassium Titanyl Phosphate

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Chinese Physics Letters 1991年第5期8卷 244-247页

作者： WANG Keming SHI Borong WANG Zhonglie ZHAO Qingtai liu Xiangdong liu Jitian liu Yaogang Department of Physics Shandong UniversityJinan 250100 Institute of Crystal Material Shandong UniversityJinan 250100

200keV Xe ions were implanted in potassium titanyl phosphate(KTP)at deferent angles:0°,45°and 60°.The lateral spread of Xe ions in KTP was studied by Rutherford backscattering of 2.1 MeV He *** result is compared w... 详细信息

关键词： prediction potassium KTP

Growth characteristics and sedimentary mode of Permian reefs,Lengwu,Tonglu,Zhejiang Province,southern China

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Journal of Palaeogeography 2016年第4期5卷 409-422页

作者： Ling liu Ya-Sheng Wu Hong-Xia Jiang Hong liu Institute of Geology and Geophysics CASKey Laboratory of Petroleum Resource ResearchChinese Academy of Sciences

Organic reefs are favourabte accumulation spaces for hydrocarbons and various mineral resources. A complete Permian organic reef profile about 44 m thick with distribution area no more than 1 km2 is exposed near Lengwu, Tongtu, Zhejiang Province. Examination of outcrops and thin sections revealed that the main reef-building organisms are catcisponges, with inozoans as dominant type. Five types of rocks have been recognized in the reef, and they are catcisponge framestone, catcisponge bafflestone, bindstone, rudstone and bioctastic wackestone. The profile was constructed in three reef-building stages. The thickness of the second stage is largest, followed by the first stage and the third stage is smallest. Each stage started with a frame-stone or bafflestone, ended as the reef grew near the sea-level, and died because of influx of terrigenous sediments. The development of the Lengwu reef is controlled by biological factors and sea-level changes. Based on the study a reef sedimentary model is established.

关键词： Reef Rock types Calcisponges Sedimentary model Permian Lengwu Southern China

Whittaker modules over loop Virasoro algebra

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Frontiers of Mathematics in China 2013年第2期8卷 393-410页

作者： Xuewen liu Xiangqian GUO Department of Mathematics Zhengzhou University Zhengzhou 450001 China

In this paper, we study Whittaker modules over the loop Virasoro algebra relative to some total order. We give a description of all Whittaker vectors for the universal Whittaker modules. We also show that any universa... 详细信息

关键词： Loop Virasoro algebra Whittaker module Whittaker vector

DECAY RATE OF SAINT-VENANT END EFFECTS FOR PLANE DEFORMATIONS OF PIEZOELECTRIC-PIEZOMAGNETIC SANDWICH STRUCTURES

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Acta Mechanica Solida Sinica 2010年第5期23卷 407-419页

作者： Yan Xue Jinxi liu Institutes of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China Department of Engineering Mechanics Shijiazhuang Tiedao University Shijiazhuang 050043 China

This paper is concerned with the decay of Saint-Venant end effects for plane deformations of piezoelectric （PE）-piezomagnetic （PM） sandwich structures, where a PM layer is located between two PE layers with the same material properties or reversely. The end of the sandwich structure is subjected to a set of self-equilibrated magneto-electro-elastic loads. The upper and lower surfaces of the sandwich structure axe mechanically free, electrically open or shorted as well as magnetically open or shorted. Firstly the constitutive equations of PE mate- rials and PM materials for plane strain are given and normalized. Secondly, the simplified state space approach is employed to arrange the constitutive equations into differential equations in a matrix form. Finally, by using the transfer matrix method, the characteristic equations for eigen- values or decay rates axe derived. Based on the obtained characteristic equations, the decay rates for the PE-PM-PE and PM-PE-PM sandwich structures are calculated. The influences of the electromagnetic boundary conditions, material properties of PE layers and volume fraction on the decay rates are discussed in detail.

关键词： Saint-Venant's principle decay rate end effect piezoelectric material piezomag- netic material sandwich structure plane deformation

Study on the Mechanical Properties of Ni-Ti-Cu Shape Memory Alloy Considering Different Cu Contents

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1601-1613页

作者： Bingfei liu Yangjie Hao Transportation Science and Engineering College Civil Aviation University of ChinaTianjin300300China Aeronautical Engineering College Civil Aviation University of ChinaTianjin300300China

By adding copper to increase the performance,the Ni-Ti-Cu Shape Memory Alloy(SMA),has been widely used in the field of engineering in recent years.A thermodynamic constitutive model for Ni-Ti-Cu SMA considering different copper contents is established in this *** results for two different copper contents,as examples,are compared with the experimental results to verify the accuracy of the theoretical *** on the verified constitutive model,the effects of different copper content on the mechanical properties of Ni-Ti-Cu SMA and the tensile and compressive asymmetric properties of Ni-Ti-Cu SMA are finally discussed,respectively.

关键词： Shape memory alloy copper contents constitutive model tension and compression asymmetric

Determination of structure-activity relationships between fentanyl analogs and human μ-opioid receptors based on active binding site models

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Neural Regeneration Research 2011年第4期6卷 267-276页

作者： Ming liu Xiaoli liu Ping Wan Qiangsan Wu Wenxiang Hu College of Life Science Capital Normal University Beijing 100048 China Department of Chemistry Capital Normal University Beijing 100048 China

Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison of three types of μ-opioid receptor protein sequence homologous rates was made. The secondary receptor structure was predicted, the model reliability was assessed and verified using the Ramachandran plot and ProTab analysis. The predictive ability of the CoMFA model was further validated using an external test set. Using the Surflex-Dock program, a series of fentanyl analog molecules were docked to the receptor, the calculation results from Biopolymer/SitelD showed that the receptor had a deep binding area situated in the extracellular side of the transmembrane domains （TM） among TM3, TM5, TM6, and TMT. Results suggested that there might be 5 active areas in the receptor. The important residues were Asp147, Tyr148, and Tyr149 in TM3, Trp293, and His297 in TM6, and Trp318, His319, Ile322, and Tyr326 in TM7, which were located at the 5 active areas. The best fentanyl docking orientation position was the piperidine ring, which was nearly perpendicular to the membrane surface in the 7 TM domains. Molecular dynamic simulations were applied to evaluate potential relationships between ligand conformation and fentanyl substitution.

关键词： μ-opioid receptor fentanyl analogs agonist active site structure-activity relationship

Review of the powder and decoction formulae in Traditional Chinese Medicine based on pharmacologically active substances and clinical evidence

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Journal of Traditional Chinese Medicine 2015年第3期35卷 355-360页

作者： liu Qihua Wen Jin Peng Zhiping liu Fenglin Tong Xiaolin Department of Pharmacy and Endocrinology Guang'an men HospitalChina Academy of Chinese Medical Sciences Department of Medical Harbin Emergency Center

Powder formulae are an indispensable part of prescription in Traditional Chinese *** formulae are characterized by good therapeutic efficacy and low dose used for their *** of the therapeutic application and material basis of pharmacological active substance in power formulae can enable the development of new powder *** in turn can contribute to reduction of wastage of drug material,relief of shortage of herbal medicinal resources and sustainable development of Traditional Chinese Medicine.

关键词： Powders Decoctions Drug prescriptions Pharmacology Medicine,Chinese traditional Review