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Influence of Slope and Slenderness Ratio on the Non-Column Volume in Skew Rolling

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Journal of Materials Science & Technology 2003年第Z1期19卷 192-194页

作者： Yongqiang KANG Zhenghuan hu jinping LIU Cuiping YANG huiping DU Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

A definition of non-column volume ratio (NCVR) is brought forward by the authors. It is influenced greatly by the slendernessratio of the cylindrical billet and the slope of the wedge on the tool of skew rolling. Using the numerical simulation, the lawof variation in NCVR during the forming process is found out. At the same time experiments have been carried out underdifferent conditions, the result of which are found to be in good agreement with the theoretical predictions.

关键词： Skew rolling, FEM, Non-column volume

Hardness estimation for covalent crystals using Empirical Electron Theory

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Chinese Science Bulletin 2010年第36期55卷 4197-4202页

作者： LUO XiaoGuang LI jinping hu Ping DONG ShanLiang Center for Composite Materials Harbin Institute of Technology Harbin 150001 China

Covalent electrons substantially determine the intrinsic hardness of inorganic crystals. A hardness model is presented on the basis of the Empirical Electron Theory generated from Pauling’s covalent bond length equation and the bond length difference method. The calculated hardness values of inorganic crystals are in good agreement with experimental and other theoretical values. Covalent bond energy with polarity correction can be used as an intrinsic indicator linking microscopic electronic structure to macroscopic hardness. A simple mathematical processing of bond energy is performed to extend the model to multi-bonding or multi-component systems. It is also found that spatial distribution of covalent bonds has a great influence on the hardness of inorganic crystals.

关键词：经验电子理论硬度指标共价键能无机晶体数学处理模型估计多组分体系差分方法

Preparation of Small Particle Sized ZnAl-Hydrotalcite-Like Compounds by Ultrasonic Crystallization

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Journal of Natural Gas Chemistry 2006年第2期15卷 100-104页

作者： Xianmei Xie Xiurong Ren jinping Li Xiaojun hu Zhizhong Wang College of Chemical Engineering ＆ Technology Taiyuan University of Technology Taiyuan 030024 China

Ultrasonic technology has been intensively studied recently due to its special features. In this paper, an ultrasonic crystallization method was introduced for the preparation of ZnAl-Hydrotalcite-Like compounds （ZnAl-HTLcs）. Samples with high crystallinity, small particle size and narrow particle size distribution were obtained and fully characterized using conventional techniques of XRD, FT-IR and TGDTA. The results prove that both ultrasonic frequency and ultrasonic power have effects on the sizes of the product particles. By varying the ultrasonic power from 250 W to 88 W, with the ultrasonic frequency fixed at 59 kHz, the median particle size of the samples increased from 0.37 μm to 0.82 μm. By altering the hydrothermal treatment time from 1 h to 5 h at 110 ℃, the median particle size of ZnAl-HTLcs synthesized via ultrasonic crystallization increased from 0.88 μm to 1.11 μm.

关键词： ultrasonic crystallization particle size distribution zinc aluminium

Design and synthesis of selective sphingosine-1-phosphate receptor 1 agonists with increased phosphorylation rates

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Acta Pharmaceutica Sinica B 2020年第6期10卷 1134-1142页

作者： Qiong Xiao Minwan hu Si Chen Yifan Tang Zeyu Shi Jing Jin jinping hu Ping Xie Dali Yin Department of Medicinal Chemistry State Key Laboratory of Bioactive Substance and Function of Natural MedicinesBeijing Key Laboratory of Active Substances Discovery and Druggability EvaluationInstitute of Materia MedicaPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100050China Departments of Drug Metabolism Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD StudyInstitute of Materia MedicaPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100050China Beijing Union Pharmaceutical Factory Beijing 102600China Department of Pharmacology State Key Laboratory of Bioactive Substance and Function of Natural MedicinesInstitute of Materia MedicaPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100050China

FTY720 and IMMH002,prodrugs for sphingosine-1-phosphate receptor 1(S1P1)agonists,show inadequate and inconsistent levels of phosphorylation in humans compared to that in *** this study,FTY720 or IMMH002 analogues(21-24)were designed and synthesized with modified head pieces to improve the biotransformation of the prodrugs to the active phosphorylated *** compounds were synthesized via a convergent route using the key and optically pure building block 9,which was first synthesized via asymmetrically catalyzed *** phosphorylation rates of these analogues in rat or human blood were *** new methyl-substituted analogue compound 21 showed higher phosphorylation rates in both rats and humans than the parent compound,whereas compound 23 showed improvements in rats,but not in *** pharmacokinetics studies of rats,compounds 21 and 23 both had higher levels of phosphorylation than FTY720 and ***,our study not only yielded new compounds with therapeutic potential,but also showed species differences between rats and humans in response to the structural modifications,which might be useful for predicting the biotransformation behavior and efficacy of this class of prodrugs in the clinic.

关键词： S1P1 agonist Prodrug Catalytic amination Phosphate formation rate Lymphocyte

Valence electron structure and bonding features of RuB2 and OSB2: The empirical electron theory calculations

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Science China(Technological Sciences) 2010年第7期53卷 1877-1885页

作者： LUO XiaoGuang, LI jinping, hu Ping & DONG ShanLiang Center for Composite Materials, Harbin Institute of Technology, Harbin 150001, China Center for Composite Materials Harbin Institute of Technology Harbin China

The valence electron structure (VES) of RuB2 and OsB2 were calculated by the empirical electron theory (EET) of solids and molecules and compared with the results derived from the first-principles calculations. The distributions of covalent electrons in different bonds indicate that B-B and B-Me have remarkably covalent bonding characters. Lattice electrons cruising around Me-Me layers are found to have great influences on electronic conductivity and high temperature plasticity. The ultra-high values of elastic constant Cn in the two compounds originate from close-packed covalent bonding along the c axis. Uneven bond strengths and distributions of covalent bonds, especially for B-Afe bonds, yield significant anisotropy. Low ratios of lattice electrons to covalent electrons suggest the intrinsic embrittlement in crystals. The fact that the calculated cohesive energies well agree with experimental results demonstrates the good suitability of the EET calculations in estimating cohesive energy for transition-metal borides.

关键词： empirical electron theory (EET) of solid and molecules valence electron structure (VES) cohesive energy anisotropy diborides of ruthenium and osmium (RuB2 and OsB2)

Pharmacokinetics of H002, a novel S1PR_1 modulator, and its metabolites in rat blood using liquid chromatography–tandem mass spectrometry

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Acta Pharmaceutica Sinica B 2016年第6期6卷 576-583页

作者： Jiaqi Mi Manman Zhao Shu Yang Shuang Yang Jing Jin Xiaojian Wang Qiong Xiao jinping hu Yan Li Department of Drug Metabolism Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD StudyKey Laboratory of Active Substances Discovery and Drug Ability Evaluation State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

A rapid and sensitive liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed and validated for the simultaneous determination of H002 and its phosphorylated metabolite, H002-P and hydroxylated metabolite H002-M, in rat blood. H001, an analogue of H002, was used as the internal *** samples were prepared by simple protein precipitation. The analytes and internal standard were separated on a Zorbax SB-C18 column with a gradient mobile phase consisting of methanol and water containing 0.1% formic acid at a flow rate of 0.2 mL /min with an operating temperature of 20 1C. The detection was performed on a triple quadrupole tandem mass spectrometer with positive electrospray ionization in multiple-reaction monitoring *** detection responses were obtained from 0.2–100 ng/mL for H002 and H002-M, while 0.5–100 ng/mL for H002-P. The intra- and inter-day precision(RSD%) was within 11.76%, with the accuracy(RE%) ranging from –9.84% to 9.12%. The analytes were shown to be stable during sample storage, preparation and analytic *** method was applied to determine the pharmacokinetics of H002 in rats, and a preliminary study showed that the pharmacokinetics of H002 correlated with its biological effect on peripheral blood lymphocytes.

关键词： S1P receptor S1PR1 modulator Sphingosine-1-phosphate S1P analogue Metabolite LC–MS/MS Pharmacokinetics Periphery blood lymphocyte

Identifying the convergent reaction path from predesigned assembled structures: Dissymmetrical dehalogenation of Br_(2)Py on Ag(111)

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Nano Research 2021年第12期14卷 4704-4713页

作者： jinping hu Zhaofeng Liang Kongchao Shen Lei Xie huan Zhang Chaoqin huang Yaobo huang Han huang Jianxin Tang Zheng Jiang Miao Yu Fei Song Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai201000China University of Chinese Academy of Sciences Beijing100100China Shanghai Synchrotron Radiation Faciality Zhangjiang LaboratoryShanghai Advanced Research InstituteChinese Academy of SciencesShanghai201000China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou215123China School of Physics Science and Electronics Central South UniversityChangsha410083China State Key Laboratory of Urban Water Resource and Environment School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin150001China

On-surface Ullmann coupling has been intensely utilized for the tailor-made fabrication of conjugated frameworks towards molecular electronics, however, reaction mechanisms are still limitedly understood. Herein, we provide a comprehensive elucidation of the surface Ullmann coupling of 2,7-dibromopyrene (Br2Py) on Ag(111) by scanning tunnelling microscopy (STM), X-ray photoelectron spectroscopy (XPS) and density function theory (DFT), and reveal that the Ullmann reaction path is unique regardless of predesigned assembled structures. By manipulating deposition conditions, diverse assembled architectures have been constructed for Br2Py on Ag(111), including the ladder phase, parallel arrangement, hexagonal patterns from monomers or Kagome lattices based on organometallic (OM) dimers. Intriguingly, stepwise annealing leads to an identical reaction diagram for the surface Ullmann coupling from individual assembled structures convergent into the brick-wall-pattern OM dimers first, which is deemed to be a stable phase, and then into elongated OM chains in order and eventually long-range polymers with direct C-C coupling. While the reaction mechanism is demonstrated to be dominated by the metal coordinated and halogen bonding motifs, interestingly, it has also been revealed that surface adatoms and dissociated Br atoms play a crucial role in coupling reactions. In contrast to previous reports demonstrating the manipulation of Ullmann reactions by preassembled strategy, herein, weak intermolecular interaction in assembled nanostructures is immediately suppressed by strong covalent bonding during reactions. Importantly, our report proposes essential insights on fundamental understanding of surface Ullmann coupling towards high-yield surface synthesis.

关键词： self-assembly Ullmann coupling organometallic intermediates reaction path scanning tunneling microscopy

Rhodojaponin Ⅵ indirectly targets Cav2.2 channels via N-ethylmaleimide-sensitive fusion protein to alleviate neuropathic pain

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Acta Pharmaceutica Sinica B 2023年第3期13卷 1326-1336页

作者： Keliang Chen Tao Wang Yong Li Jun Wu Cheng-Xiao Zhao Sheng Liu Fengrun Sun Yehong Fang Jiahuan hu jinping hu Chong-Jing Zhang Haibo Yu Chao Ma Shi-Shan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Institute of Basic Medical Sciences Neuroscience CenterChinese Academy of Medical SciencesDepartment of Human AnatomyHistology and EmbryologySchool of Basic MedicinePeking Union Medical CollegeBeijing 100005China

Neuropathic pain is a chronic disease that severely afflicts the life and emotional status of patients,but currently available treatments are often *** therapeutic targets for the alleviation of neuropathic pain are urgently *** Ⅵ,a grayanotoxin from Rhododendron molle,showed remarkable antinociceptive efficacy in models of neuropathic pain,but its biotargets and mechanisms are *** the reversible action of rhodojaponin Ⅵ and the narrow range over which its structure can be modified,we perforwmed thermal proteome profiling of the rat dorsal root ganglion to determine the protein target of rhodojaponin Ⅵ.N-Ethylmaleimide-sensitive fusion(NSF) was confirmed as the key target of rhodojaponin Ⅵ through biological and biophysical *** validation showed for the first time that NSF facilitated trafficking of the Cav2.2 channel to induce an increase in Ca2+current intensity,whereas rhodojaponin Ⅵ reversed the effects of *** conclusion,rhodojaponin Ⅵ represents a unique class of analgesic natural products targeting Cav2.2 channels via NSF.

关键词： Natural product Rhodojaponin VI Neuropathic pain NSF Cav2.2

A novel S1P1 modulator IMMH002 ameliorates psoriasis in multiple animal models

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Acta Pharmaceutica Sinica B 2020年第2期10卷 276-288页

作者： Jing Jin Nina Xue Yuan Liu Rong Fu Mingjin Wang Ming Ji Fangfang Lai jinping hu Xiaojian Wang Qiong Xiao Xiaoying Zhang Dali Yin Liping Bai Xiaoguang Chen Shuan Rao State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100050China Department of Thoracic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China State Key Laboratory of Quality Research in Chinese Medicine Macao Institutefor Applied Research in Medicine and HealthMacao University of Science and TechnologyTaipaMacao SAR 999078China

Psoriasis is characterized by abnormal proliferation of keratinocytes,as well as infiltration of immune cells into the dermis and epidermis,causing itchy,scaly and erythematous plaques of *** understanding of this chronic inflammatory skin disease remains unclear and all available treatments have their limitations ***,we showed that IMMH002,a novel orally active S1 P1 modulator,desensitized peripheral pathogenic lymphocytes to egress signal from secondary lymphoid organs and *** different psoriasis animal models,we demonstrated that IMMH002 could significantly relieve skin damage as revealed by PAS I score and pathological injure ***,IMMH002 regulated CD3+T lymphocytes re-distribution by inducing lymphocytes’homing,thus decreased T lymphocytes allocation in the peripheral blood and skin but increased in the *** results suggest that the novel SIP1 agonist,IMMH002,exert extraordinary capacity to rapidly modulate T lymphocytes distribution,representing a promising drug candidate for psoriasis treatment.

关键词： S1P1 S1P1 agonist IMMH002 Lymphocyte Psoriasis