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A Concise,Practical Chiral Resolution Approach of Racemic (E)-4,4-Dimethyl-1-(4-nitrophenyl) pent-1-en-3-ol to Its both Enantiomers via strategy of Diastereomeric Ester Formation and Crystallization Using both N-Boc-D- and N-Boc-L-phenylglycines as Chiral Auxiliaries

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Chemical Research in Chinese Universities 2024年第6期40卷 1096-1105页

作者： JIANG shanshan YUAN Jia QIN Yanlan LUO Ying JIN Zhengsheng ZHAO Guilong ti Huihui school of Chinese Materia Medica Guangdong Pharmaceutical UniversityGuangzhou 510006P.R.China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan 528400P.R.China shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203P.R.China school of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityGuangzhou 510006P.R.China

Chiral secondary alcohols are an important class of functionalities commonly seen in drugs and other bioactive *** an ongoing drug discovery program in our laboratories,a nitro-bearing racemic allylic secondary alcohol (±)-1 was discovered as a promising drug candidate,and in the following preclinical studies,a concise,reliable,practical synthetic approach to its both enantiomers with high optical purities was greatly *** the present study,we developed a chiral resolution approach of (±)-1 to its both enantiomers,i.e.,(+)-1 and (-)-1,via the strategy of diastereomeric ester formation and crystallization using both N-Boc-D- and N-Boc-L-phenylglycines as chiral *** absolute configurations of all the four key intermediates were unambiguously determined by single-crystal X-ray diffraction,providing a solid foundation for the stereochemistry of the present *** two enantiomers were obtained in high optical *** approach is characterized by scalability and practicality and is envisaged to enable the chiral resolution of other racemic secondary alcohols,especially those with labile groups,such as NO_(2);olefinic C=C bond.

关键词： Chiral resolution Phenylglycine Chiral auxiliary Chiral secondary alcohol Diastereomeric ester formation

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study on pick arrangement of shearer drum based on load fluctuation

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Journal of China University of Mining and Technology 2008年第2期18卷 305-310页

作者： DU Chang-long LIU song-yong CUI Xin-xia LI ti-jian school of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China tian-di science ＆ Technology Co. Ltd Coal Mining Branch China Coal Research Institute Beijing 100013 China

According to the coal or rock cutting theory, a mechanical model and computing formula for a pick and the drum load fluctuation model were established in order to obtain relationships between pick arrangements and drum fluctuation loads, drum rotary speeds and haulage speeds. Based on a minimum load fluctuation, an optimal mathematical model was established for drum pick arrangements. The effects of pick arrangements （including punnett square, sequence, aberrance Ⅰ and Ⅱ） on the drum load fluctuation coefficient are discussed. The relationships between the pick arrangements of the drum with different start vanes and the cutting load fluctuation coefficient, the drum rotary speed and haulage speed were also studied. The results indicate that the punnett square arrangement has a smaller cutting load fluctuation coefficient than other forms of arrangement and the drum with the 4-start vanes has the smallest coefficient. The drum rotary speed and haulage speed are affected not only by pick arrangements, but also by the number of vanes.

关键词： pick arrangement mechanical pick model load fluctuation model load fluctuation coefficient

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Effects of sm addition on microstructural evolution of Mg-6Zn-0.4Zr alloy during semi-solid isothermal heat treatment

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China Foundry 2017年第2期14卷 85-92页

作者： Yu Zhang Xiao-feng Huang Ying Ma ti-jun Chen Yuan Hao state Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology Lanzhou 730050 China

The application of segmental semi-solid thixoforming of magnesium alloys is confined due to the dimensional distinction existing in solid particles of the alloy billet from edge to center zones. In the present study, the effects of sm addition on the microstructural evolution of Mg-6Zn-0.4Zr and Mg-6Zn-4sm-0.4Zr alloys by semi-solid isothermal heat treatment were investigated, to obtain optimum semi-solid microstructures for the subsequently thixoforming. The results indicate that the grains of the sm-bearing alloy are evidently refined and gradually evolve from dendritic to globular and elliptic particles. In addition, the distinctly dimensional effect of the Mg-6Zn-0.4Zr alloy is eliminated with 4% sm addition; the particle sizes in all zones from center to the edge of the billet are almost identical. With the increment of isothermal heat treatment temperature, the dendritic microstructures completely disappear, and meanwhile, the irregular and globular particles gradually form. The size, morphology and the distribution of solid particles mainly depend on the formation and permeation of the liquid phase in the process of isothermal heat treatment. As the isothermal temperature increases from 570 °C to 610 °C, the average size and shape factor of solid particles of both the alloys with and without sm addition gradually decrease while the liquid fraction gradually increases.

关键词： Mg-Zn-Zr magnesium alloy dimensional effect sm semi-solid isothermal heat treatment non-dendritic microstructure

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Improvement of Mechanical Properties of Cr-Ni-Mo-Cu-ti stainless steel With Addition of Vanadium

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Journal of Iron and steel Research International 2007年第6期14卷 74-78页

作者： s M Abbasi A shokuhfar Advanced Materials Research Laboratory K. N. Toosi University of Technology Tehran 165698391 Iran

The effect of vanadium （V） addition on the mechanical properties of a Cr-Ni-Mo-Cu-ti stainless steel was studied and its influence on microstructural changes was also investigated. Results indicate that the structure of the solution-treated specimens mainly comprises of austenite-martensite, and adding V leads to the formation of a consid erable amount of ferrite. Under this condition, austenite phase is not mechanically stable, and transforms to martensite by plastic deformation. The addition of 0.5% - 1.0% （in mass percent） of V increases the hardness and the strength of the 80% cold rolled and aged steel, without any effect on ductility. Improvement in mechanical properties is presumably attributed to the formation of a small amount of ferrite in the primary structure, and the formation of certain precipitates is accelerated by the addition of V during aging. By contrast, excessive V decreases the strength and ductility simultaneously. This is due to the strong effect of ferrite formation compared to the beneficial effect of precipitation. The loss of ductility caused by adding higher amount of V is due to the formation of ferrite phases which in turn are suitable nucleation sites for crack propagation.

关键词： stainless steel vanadium microstructure mechanical property

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Probing cell membrane integrity using a histone-targeting protein nanocage displaying precisely positioned fluorophores

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Nano Research 2023年第1期16卷 894-904页

作者： ti Fang Chaoqun Li Ao Liang Hui Zhang Fan Zhang Xian-En Zhang Yi-Yu Yang Feng Li Guangzhou Women and Children’s Medical Center Guangzhou Medical UniversityGuangzhou 510120China state Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Faculty of synthetic Biology Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China

Cell membrane integrity is fundamental to the normal activities of cells and is involved in both acute and chronic ***,we report a probe for analyzing cell membrane integrity developed from a 9 nm-sized protein nanocage named Dps via fluorophore conjugation with high spatial precision to avoid *** probe cannot enter normal live cells but can accumulate in dead or live cells with damaged membranes,which,interestingly,leads to weak cytoplasmic and strong nuclear *** differential staining is found attributed to the high affinity of Dps for histones rather than DNA,providing a staining mechanism different from those of known membrane exclusion probes(MEPs).Moreover,the Dps nanoprobe is larger in size and thus applies a more stringent criterion for identifying severe membrane damage than currently available *** study shows the potential of Dps as a new bioimaging platform for biological and medical analyses.

关键词： protein engineering fluorescent probes nanoparticles cell membrane damage ferritin superfamily

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Identification of glycerophospholipid fatty acid remodeling by using mass spectrometry imaging in bisphenol s induced mouse liver

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Chinese Chemical Letters 2018年第8期29卷 1281-1283页

作者： Chao Zhao Peisi Xie ti Yang Hailin Wang Arthur Chi Kong Chung Zongwei Cai state Key Laboratory of Environmental and Biological Analysis Department of Chemistry Hong Kong Baptist University state Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Bisphenol A（BPA） plays an important role in metabolic disorders. As a major alternative to BPA, it is unclear whether the exposure of bisphenol s（BPs） may result in lipidome disturbance. Using a mouse model, we investigated the effects of BPs exposure on metabolism and spatial distribution of lipids by using lipidomics analysis and matrix-assisted laser desorption/ionization（MALDI）-mass spectrometry imaging（MsI） in mouse liver tissues. Lipid metabolites displayed significant up-regulation in phosphatidylethanolamines（PE）, lysophosphatidylcholines（LPC）, lysophosphatidylethanolamines（LPE） and lysophosphatidylserine（LPs） as well as remarkable down-regulation in phosphatidylcholine（PC） and phosphatidylserine（Ps） in mouse liver after the exposure at 100 m g BPs/kg body weight/*** obtained results indicated that the lipidome of liver was perturbed significantly in glycerophospholipid（GP） fatty acid remodeling pathway upon the BPs exposure. We applied MsI and multivariate statistical analysis to evaluate the abundance variation of lipid markers in BPs-treated liver sections and to compare with the analytical results from olive oil-treated liver sections. Differential structural lipids with up-regulated PE（20：1/20：4）, LPC（20：4）, LPE（20：4）, LPs（33：4） and down-regulated PC（20：4/22：6）and Ps（18：0/22：6）, which were related to GP fatty acid remodeling, changed and co-localized in the liver sections. To explore the cause of variation of lipid abundance, expression of enzymes that regulate biosynthesis and metabolism of fatty acid in liver tissues were analyzed. Consistent with the results of liver lipidome and spatial distribution, a decrease in hepatic expression of LPC acyltransferase 1（LPCAT1）,LPCAT2 and LPs acyltransferase and an increase expression of LPCAT3, LPCAT4, LPE acyltransferase 1（LPEAT1）, LPEAT2 and phospholipase A2 s were observed in GP fatty acid remodeling pathway. Our results demonstrated that exposure to BPs could induce the GP fatty acid remodeling, which m

关键词： Lipidomics MALDI-MsI Bisphenol s Bisphenol A Mouse liver

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A computational study on system dynamics of an ocean current turbine

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Journal of Hydrodynamics 2018年第3期30卷 395-402页

作者： Jo-ti Wu Jiahn-Homg Chen Ching-Yeh Hsin Fomg-Chen Chiu Department of systems Engineering and Naval Architecture National Taiwan Ocean University Keelung China Department of Engineering science and Ocean Engineering National Taiwan University Taipei China

In this paper, we present the study of system dynamics of the floating kuroshio turbine（FKT） system which is designed to harness ocean current energy. We focus on the mooring line system design and its interaction with the FKT system. The effects of line diameter and two different auxiliary line systems were studied. Their responses in waves were also investigated. We integrated several commercial and in-house packages. The system buoyancy and weight and their centers were estimated using the Rhino software. The system hydrodynamic coefficients were obtained through WAMIT, system drag coefficient through FLUENT, turbine propulsive force through lifting surface code, and system dynamics through Orca Flex. The results show that the mooring line system can create strong influence on the FKT system operations in the ocean current environments.

关键词： Ocean current energy current turbine system dynamics mooring line system

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Adaptive T cell immunotherapy in cancer

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science China(Life sciences) 2021年第3期64卷 363-371页

作者： Dongdong ti Miaomiao Bai Xiaolei Li Jianshu Wei Deyun Chen Zhiqiang Wu Yao Wang Weidong Han Bio-therapeutic Department Chinese PLA General HospitalBeijing 100853China

Impaired tumor-specific effector T cells contribute to tumor progression and unfavorable clinical outcomes. As a compensatoryT cell-dependent cancer immunoediting strategy, adoptive T cell therapy (ACT) has achieved encouraging therapeutic results,and this strategy is now on the center stage of cancer treatment and research. ACT involves the ex vivo stimulation and expansionof tumor-infiltrating lymphocytes (tiLs) with inherent tumor reactivity or T cells that have been genetically modified to expressthe cognate chimeric antigen receptor or T cell receptor (CAR/TCR), followed by the passive transfer of these cells into alymphodepleted host. Primed T cells must provide highly efficient and long-lasting immune defense against transformed cellsduring ACT. Anin-depth understanding of the basic mechanisms of these living drugs can help us improve upon currentstrategies and design better next-generation T cell-based immunotherapies. From this perspective, we provide an overview ofcurrent developments in different ACT strategies, with a focus on frontier clinical trials that offer a proof of principle. Meanwhile,insights into the determinants of ACT are discussed, which will lead to more rational, potent and widespread applicationsin the future.

关键词： adoptive T cell therapy tumor-infiltrating lymphocytes chimeric antigen receptor T cell receptor

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Pancreatic cancer and depression

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World Journal of Clinical Cases 2023年第12期11卷 2631-2636页

作者： Kalliopi Michoglou Amsajini Ravinthiranathan saw san ti saoirse Dolly Kiruthikah Thillai Department of Oncology Guy's and St Thomas'NHS Foundation TrustLondon Se19RTUnited Kingdom

Pancreatic cancer is a highly devastating disease with high mortality *** patients who undergo potential curative surgery have a high risk for *** incidence of depression and anxiety are higher in patients with cancer than the general ***,patients with pancreatic cancer are at most of risk of both depression and anxiety and there seems to be a biological *** some patients,depression seems to be a precursor to pancreatic *** this article we discuss the biological link between depression anxiety and hepatobiliary malignancies and discuss treatment strategies.

关键词： Pancreatic cancer Depression Anxiety Cytokines Gastrointestinal malignancies

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Production of Graphene Nanospheres by Annealing of Graphene Oxide in solution

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Nano Research 2011年第7期4卷 705-711页

作者： Jian Zheng Hongtao Liu Bin Wu Yunlong Guo ti Wu Gui Yu Yunqi Liu Daoben Zhu Beijing National Laboratory for Molecular sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of sciences Beijing 100039 China

We report a simple method to produce graphene nanospheres （GNss） by annealing graphene oxide （GO） solution at high-temperature with the assistance of sparks induced by the microwave absorption of graphite flakes dispersed in the solution. The GNss were formed by rolling up of the annealed GO, and the diameters were mostly in the range 300-700 nm. The GNs exhibited a hollow sphere structure surrounded by graphene walls with a basal spacing of 0.34 nm. Raman spectroscopy and X-ray photoelectron spectroscopy of the GNss confirmed that the GO was efficiently reduced during the fabrication process. The resulting GNss may open up new opportunities both for fundamental research and applications, and this method may be extended to the synthesis of other nanomaterials and the fabrication of related nanostructures.

关键词： Graphene nanosphere self-assembly microwave anneal

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