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SYNTHESIS AND CHARACTERIZATION OF NOVEL REACTIVE POLYORGANOSILOXANE CONTAINING NITRO GROUPS

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Chinese Journal of Polymer Science 2001年第1期19卷 1-6页

作者： Chun-qing liu yang liu ping Xie Rong-ben Zhang Chao-bin He Neal Tai-shung Chung PCLCC Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Institute of Materials Research and Engineering National University of Singapore Singapore 119260 Institute of Materials Research and Engineering National University of Singapore Singapore 119260

A novel reactive polyorganosiloxane containing nitro groups was first prepared by acid-catalyzed equilibration polymerization. The monomer, 3-(4-nitrophenoxy)propylmethyldichlorosilane (NPPMS), was synthesized by hydrosilylation reaction with dicyciopentadienylplatinum(II) chloride (Cp2PtCl2) catalyst in high yield. The synthesized polynitroorganosiloxane, which has potential application as a precursor for synthesizing advanced functional polymers, was characterized by FTIR, H-1-NMR, C-13-NMR, Si-29-NMR, vapor pressure osmometry (VPO) and gel permeation chromatography(GPC).

关键词： polyorganosiloxane equilibration polymerization hydrosilylation characterization

Cloning and characterization of a novel hepatitis B virus core binding protein C12

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World Journal of Gastroenterology 2005年第36期11卷 5666-5671页

作者： Yin-Ying Lu Jun Cheng Yong-ping yang Yan liu Lin Wang Ke Li Ling-Xia Zhang Gene Therapy Research Center Institute of Infectious Diseases The 302 Hospital of PLA 100 Xisihuanzhong Road Beijing 100039 China

AIM： To elucidate the biological function of HBV core antigen （HBcAg） on pathogenesis of hepatitis B, a novel gene C12 coding for protein with unknown function interacting with HBcAg in hepatocytes was identified and characterized. METHODS： HBcAg bait plasmid pGBKT7-HBcAg was constructed and transformed into yeast AH109, then the transformed yeast was mated with yeast Y187 containing liver complementary DNA （cDNA） library plasmid in 2xYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium （SD/-Trp-Leu-His-Ade） and synthetic dropout nutrient medium （SD/-Trp-Leu-His-Ade） containing X-α-gal for screening twice. After extracting and sequencing of plasmid from blue colonies, we isolated a cDNA clone encoding a novel protein designated as C12 that directly interacted with HBcAg. The interaction between HBcAg and C12 was verified again by re-mating. pEGFP-N1-C12 fluorescent protein fusion gene was transfected in 293 and L02 cell, and observed by fluorescent microscope. M-FI reduction assay was used to study the action of C12 protein effect on metabolism of mammal cell. Yeast two-hybrid and cDNA microarray were performed to search binding protein and differential expression genes regulated by C12 protein. RESULTS： C12 gene was screened and identified by yeast two-hybrid system 3. The interaction between HBcAg and the novel protein coded by the new gene C12 was further confirmed by re-mating. After 48 h, fluorescence of fusion protein could be observed steadily in the 293 and L02 cell plasma. Under MTT assay, we found that the expression of C12 did not influence the growth of liver cells. Seventeen differential expression genes in HepG2 cells transfected with C12 protein expression plasmid by cDNA microarray, of which 16 genes were upregulated and 1 gene was downregulated by C12 protein. Twenty-one colonies containing 16 different genes coding for C12 protein binding proteins were isolated by yeast two-hybrid, there were 2 new genes with unknown function.

关键词： Hepatitis B virus core antigen Yeast two-hybrid cDNA microarray MTT assay

C02 adsorption performance of ZIF-7 and its endurance in flue gas components

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Frontiers of Environmental Science & Engineering 2014年第2期8卷 162-168页

作者： Jiangkun XIE Naiqiang YAN Fei liu Zan QU Shijian yang ping liu School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Porous ZIF-7 with the sodalite （SOD） cage structure （ZIF, Zeolitic imidazolate framework） were synthesized by the solvothermal method. Synthesized material was characterized by powder X-ray diffraction （PXRD）, thermal gravity （TG）, scanning electron micro- scopy （SEM） and Na adsorption analysis. ZIF-8 with the SOD structure and a littl larger pore window was synthesized in a similar way and was characterized for comparisons. Thermal stability and structural stability of ZIF-7 were tested through PXRD analysis, and the capability of the material for CO2 capture from simulated flue gas was investigated through physical adsorption method. The results showed that CO： adsorption capacity on ZIF-7 was about 48 mL. gl while the capacity on ZIF-8 was about 18mg.g-1 （at 12C and 0.98 P/Po relative pressure）. Furthermore, the impact of flue gas components on adsorption capacity of ZIF-7 and the selectivity of CO2 against N2 on ZIF-7 was also investigated in this work

关键词： ZIF-7 structural stability CO2 capture ther- mal stability

Human Sulfatase-1 Improves the Effectiveness of Cytosine Deaminase Suicide Gene Therapy with 5-Fluorocytosine Treatment on Hepatocellular Carcinoma Cell Line HepG2 In Vitro and In Vivo

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Chinese Medical Journal 2015年第10期128卷 1384-1390页

作者： Xiao-ping yang Ling liu ping Wang Sheng-Lin Ma Department of General Surgery Hangzhou First People's Hospital Hangzhou Hospital Affiliated to Nanjing Medical University Hangzhou Zhejiang 310006 China

Background：Human sulfatase-1 （Hsulf-l） is an endosulfatase that selectively removes sulfate groups from heparan sulfate proteoglycans （HSPGs）,altering the binding of several growth factors and cytokines to HSPG to regulate cell proliferation,cell motility,and *** investigated the role of combined cancer gene therapy with Hsulf-l and cytosine deaminase/5-fluorocytosine （CD/5-FC） suicide gene on a hepatocellular carcinoma （HCC） cell line,HepG2,in vitro and in ***：Reverse transcription polymerase chain reaction and immunohistochemistry were used to determine the expression of Hsulf-1 in *** apoptosis was observed through flow cytometry instrument and mechanism of Hsulf-1 to enhance the cytotoxicity of 5-FC against HCC was analyzed in HCC by confocal *** also establish a nude mice model of HCC to address the effect of Hsulf-1 expression on the CD/5-FC suicide gene therapy in ***：A significant decrease in HepG2 cell proliferation and an increase in HepG2 cell apoptosis were observed when Hsulf-1 expression was combined with the CD/5-FC gene suicide system.A noticeable bystander effect was observed when the Hsulf-1 and CD genes were *** calcium was also increased after HepG2 cells were infected with the Hsulf-1 *** vivo studies showed that the suppression of tumor growth was more pronounced in animals treated with the Hsulf-1 plus CD than those treated with either gene therapy alone,and the combined treatment resulted in a significant increase in ***：Hsulf-1 expression combined with the CD/5-FC gene suicide system could be an effective treatment approach for HCC.

关键词： Cytosine Deaminase/5-Fluorocytosine Suicide System Hepatocellular Carcinoma Human Sulfatase-1

Effects of Triggering Oocytes Maturation by rhCG 250 μg vs uhCG 10 000 IU on the Outcomes of IVF-ET Treatment in Chinese Population:A Cohort Study

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Journal of Reproduction and Contraception 2013年第1期24卷 21-29页

作者： Rui yang Rong LI ping liu Xin-na CHEN Cai-hong MA Jie QIAO Department of Obstetrics and Gynecology Reproductive Medical Center Peking University Third Hospital

Objective To compare the effects of recombinant hCG （rhCG） 250 μg and urinary hCG （uhCG） 10 000 1U on triggering oocyte maturation during COH/1VF-ET in Chinese women. Methods A retrospective cohort study which included COH/1VF-ET cases at reproductive medical center of Peking University Third Hospital from March to May 2010 was performed. Analysis of covariance （ANCOVA） was taken for data analysis. Results There were 318 cycles （group A） using rhCG 250μg and 810 cycles （group B） using uhCG 10 000 1U for triggering. In 1VF procedure, there were no significant differences in the number of oocyte retrieval, 2PN fertilization rate, good-quality embryo rate, embryo implantation rate and clinical pregnancy rate between the two groups. The delivery weeks, mean neonatal birth weight and live birth rates were also similar between the two groups. There was no local allergic reaction after injection or neonatal birth defect in group A. Conclusion The rhCG 250 μg and uhCG 10 000 IU have equal effects on triggering oocyte maturation for patients with normal ovarian function in Chinese population. rhCG may have even lower local discomfort occurrence.

关键词： recombinant hCG (rhCG) urinary hCG (uhCG) in vitro fertilization-embryo transfer (IVF-ET)

cDNA Cloning of c33-c Antigen Gene Derived From NS3 Region of Chinese HCV Genome, Expression in Escherichia coli and Development of HCV EIA Second-Generation Diagnostic Kit

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Science China Chemistry 1994年第2期37卷 190-202页

作者： yang Yong-ping liu Chong-Bai JIN Dong-YanZHAN Mei-Yun TANG Quan XIA Ning-ShaoCAO Jing-Yuan and LI Jing-Yuan Institute of Virology Chinese Academy of Preventive Medicine Beijing 100052 PRC

A cDNA fragment of about 860 bp corresponding to the c33-c gene in the non-structural region 3 (NS3) of HCV genome was obtained from one plasma derived from a Chinese HCV carrier who came from Tai'an of Shandong Province, China by the application of reverse transcription (RT) and polymerase chain reaction (PCR) techniques. After the sequence of the cDNA fragment was determined and compared with the equivalent region of. the HCV-I (HCV-US) and HCV-II (HCV-BK) genomes, the nucleotide/ amino acid sequence homologies were found to be 79. 2%/91. 3% and 91. 3%/93. 9%, respectively. The prokaryotic expression vector pBV220 was employed for the overproduction of c33-c native recombinant protein in E. coli cells. The expression products were detected by enzyme-linked immunosorbent assay (ELISA) and Western blotting with antisera of chronic hepatitis C patients, and a molecular weight 31 kD of c33-c viral protein was shown to account for 14% of the total cellular soluble proteins. This product was extracted from the bacterial lysate by lysozyme, Triton X-100 and urea treatment, and purified through ion exchange chromatography. The purified c33-c protein combined with a branch peptide MAP-C-19 representing immunodominant epitopes on the nucleocapsid region of HCV genome was used to develop a Chinese HCV EIA 2nd-generation diagnostic kit for the detection of anti-HCV antibodies. Its specifity, sensitivity and re-producibility were all in keeping with the indexes of the national standard for the quality control of the HCV diagnostic kit. The agreement rate between our kit and Abbott company's HCV EIA second-generation diagnostic kit was 99. 33% , and the identified rate of positive anti-HCV of our kit was 2% more than that of the Abbott company's kit.

关键词： HCV cDNA cloning overproduction of recombinant protein expression protein purification HCV EIA diagnostic kit.

Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin liu Guanghui liu Wei DAI Hanzhe yang Haibo ZHENG Zhi WANG Ran NIU Yifan BAI yang ZHANG Chengbao liu Ge yang Junwei yang Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the Chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan yang Han Jia Tuo liu Yuzhen yang Jun yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing yang Si liu YiHua He Chang yang YuYue Jin ZhouKun Deng ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field