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A rapid protein sample preparation method based on organic-aqueous microwave irradiation technique

Science China Chemistry 2015年第3期58卷 526-531页

作者： Shuaibin Wu Hongfei Zhang Kaiguang Yang Junfeng Ma Zhen Liang Lihua Zhang Yukui Zhang Key Laboratory of Separation Sciences for Analytical Chemistry National Chromatographic R&A CenterDalian Institute of Chemical Physics Chinese Academy of Sciences China national Tobacco quality supervision and test center College of Chemistry and Chemical Engineering Hubei Normal University Department of Biological Chemistry the Johns Hopkins University School of Medicine

Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimized organic-aqueous solvent system for protein identification. Specifically, protein solutions containing high-concentration acetonitrile were subjected to 5 min microwave irradiation. After cooling down, trypsin was added and the digestion was performed with 30 s microwave irradiation, and the resulting peptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS). A shortened processing time of only 5.5 min is needed with this method(more than 12 h is necessary in the traditional overnight protein sample preparation). Moreover, due to the absence of urea and other chaotropic reagents, the digests can be readily identified by MALDI-TOF MS. When an assessment of this method was performed by digesting a model protein BSA, 69% ± 3% sequence coverage corresponding to 47 ± 3 peptides was obtained, which shows better protein identification than that from the standard overnight protein sample preparation method(51% ± 2% sequence coverage and 23 ± 1 peptides). Another model protein α-casein was used for the analysis of protein phosphorylation with the newly developed method that yielded 4 phosphopeptides with 8 phosphorylation sites, whereas 3 phosphopeptides with 2 phosphorylation sites were obtained from the traditional overnight approach. Moreover, the organic-aqueous microwave irradiation method provides effective digestion for proteins down to fmol.

关键词： MALDI-TOF MS microwave organic-aqueous solvent protein identification digestion

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Macro-and Micro-Properties of Two Natural Marine Clays in China

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China Ocean Engineering 2009年第2期23卷 329-344页

作者：蒋明镜彭立才朱合华林奕禧黄良机 Department of Geotechnical Engineering Tongji University Zhuhai center for supervision and Inspection on quality of Infrastructure Engineering

In this paper,macro-and micro-properties of natural marine clay in two different and representative regions of China are investigated in *** addition to in-situ tests,soil samples are collected by use of Shelby tubes for laboratory examination in Shanghai and Zhuhai respectively,two coastal cities in *** the laboratory tests,macro-properties such as consolidation characteristics and undrained shear strength are ***,X-ray diffraction test,scanning electron microscope test,and mercury intrusion test are carried out for the investigation of their micro-properties including clay minerals and *** study shows that：（1）both clays are Holocene series formations,classified as either normal or underconsolidated *** initial gradient of the stress-strain curves shows their increase with increasing consolidation pressure;however,the Shanghai and the Zhuhai clays are both structural soils with the latter shown to be more structured than the *** a result,the Zhuhai clay shows strain softening behavior at low confining pressures,but strain hardening at high *** contrast,the Shanghai clay mainly manifests strain-hardening.（2）An activity ranges from 0.75 to 1.30 for the Shanghai marine clay and from 0.5 to 0.85 for the Zhuhai marine *** main clay mineral is illite in the Shanghai clay and kaolinite in the Zhuhai *** Zhuhai clay is mainly characterized by a flocculated structure,while the typical Shanghai clay shows a dispersed *** porous structure of the Shanghai clay is characterized mainly by large and medium-sized pores,while the Zhuhai clay porous structure is mainly featured by small and medium-sized *** differences in their macro-and micro-properties can be attributed to different sedimentation environments.

关键词： marine clay macro- and micro- properties comparison microstructure

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Quantitative ^(31)P NMR Analysis of Lignocellulosic Materials in Ionic Liquids

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Chemical Research in Chinese Universities 2010年第3期26卷 488-490页

作者： SUN Hui XU Ying-kai XU Guo-zhi Department of Materials Science and Engineering National Center for Quality Supervision and Test of Plastic Products Beijing Technology and Business University Beijing 100048 P R. China Department of Surgery University of Pittsburgh Pennsylvania 15213 USA

In an effort to utilize NMR technique for the analysis of the structural components of wood and biomasses such as lignin, we made a comparative study of lignin contents of several types of lignocellulosie materials both before and after enzymatic hydrolyses. To this end, Eucalyptus Globulus, Norway spruce thermomeehanieal pulp（TMP） corn stover and Eucalyptus kraft pulp were ball-milled and treated with cellulase to prepare materials with high lignin contents. These materials were analyzed via ^31p NMR in ionic liquids. The results show that the contents of various functional groups for the lignocellulosic materials after enzymatic hydrolyses are generally in agreement with those from their corresponding enzymatic mild acidolysis liginins（EMALs）, indicating that ^31p NMR analysis of lignocellulosic materials in ionic liquids is a promising method for quantitative characterization of lignocellulosic materials.

关键词： Structural characterization ^31p NMR Enzymatic mild acidolysis lignin(EMAL)

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Soft measurement model of ring's dimensions for vertical hot ring rolling process using neural networks optimized by genetic algorithm

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Journal of Central South University 2017年第1期24卷 17-29页

作者：汪小凯华林汪晓旋梅雪松朱乾浩戴玉同 Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China College of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China Hubei Collaborative Innovation center for Automotive Components Technology Wuhan 430070China national automobile quality supervision test center Xiangyang 441004China Zhangjiagang Hailu Annular Forgings Co. Ltd.Zhangjiagang 215626China

Vertical hot ring rolling(VHRR) process has the characteristics of nonlinearity,time-variation and being susceptible to ***,the ring's growth is quite fast within a short time,and the rolled ring's position is *** of these cause that the ring's dimensions cannot be measured *** analyzing the relationships among the dimensions of ring blanks,the positions of rolls and the ring's inner and outer diameter,the soft measurement model of ring's dimensions is established based on the radial basis function neural network(RBFNN).A mass of data samples are obtained from VHRR finite element(FE) simulations to train and test the soft measurement NN model,and the model's structure parameters are deduced and optimized by genetic algorithm(GA).Finally,the soft measurement system of ring's dimensions is established and validated by the VHRR *** ring's dimensions were measured artificially and calculated by the soft measurement NN *** results show that the calculation values of GA-RBFNN model are close to the artificial measurement *** addition,the calculation accuracy of GA-RBFNN model is higher than that of RBFNN *** research results suggest that the soft measurement NN model has high precision and *** research can provide practical methods and theoretical guidance for the accurate measurement of VHRR process.

关键词： vertical hot ring rolling dimension precision soft measurement model artificial neural network genetic algorithm

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Determination of tobacco-specific N-nitrosamines in mainstream cigarette smoke employing graphene/Fe3O4 composite as sorbent prior to LC-MS/MS

Determination of tobacco-specific N-nitrosamines in mainstre...

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中国化学会第22届全国色谱学术报告会及仪器展览会

作者： Yan-Bo Luo Xiao-Jing Chen Xiang-Yu Li Hong-Fei Zhang Xing-Yi Jiang Feng-Peng Zhu Yong-Qiang Pang China national Tobacco quality supervision and test center

Tobacco-specific N-nitrosamines(TSNAs) are a source of carcinogenicity in mainstream cigarette smoke(MSS). To disclosure and regulation of harmful components release in cigarette, a magnetic solid-phase extraction(MSPE) procedure using graphene/FeO composite as sorbent for fast enrichment of trace TSNAs in MSS was developed. Under the optimal conditions,

关键词： magnetic solid-phase extraction(MSPE) graphene/Fe3O4 composite tobacco-specific N-nitrosamines(TSNAs) mainstream cigarette smoke(MSS)

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Simultaneous determination of polycyclic aromatic hydrocarbons and tobacco-specific N-nitrosamines in mainstream cigarette smoke using in-pipette-tip solid-phase extraction and on-line gel permeation chromatography-gas chromatography–tandem mass spectrome

Simultaneous determination of polycyclic aromatic hydrocarbo...

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中国烟草学会2017年学术年会

作者： Yan-Bo Luo Xiao-Jing Chen Hong-Fei Zhang Xing-Yi Jiang Xue Li Xiang-Yu Li Feng-Peng Zhu Yong-Qiang Pang Hong-Wei Hou China national Tobacco quality supervision and test center

In this study, a silica/primary secondary amine(Si O2/PSA) was used as an in-pipette-tip solid phase extraction(SPE) sorbent for the simultaneous determination of polycyclic aromatic hydrocarbons(PAHs)and tobacco-specific N-nitrosamines(TSNAs) in mainstream cigarette smoke(MSS). We investigated several parameters including an extraction procedure of total particulate matter, type and amount of sorbent and on-line gel permeation chromatography parameters to obtain optimum conditions for a new strategy to target analytes. Under the optimized conditions, we developed a method for the simultaneous determination of PAHs and TSNAs in MSS by coupling in-pipette-tip SPE procedures to an on-line gel permeation chromatography-gas chromatography–tandem mass spectrometry(on-line GPC-GC–MS2).Our method had limits of detection for target analytes ranging from 0.01 to 0.23 ng/cig. Good linearities were obtained with coefficients of determination(R2) greater than 0.9984 for all target analytes. Good reproducibility was obtained as intra-and inter-day precisions, and the relative standard deviations were less than 11.4 and 13.3%, respectively. The recoveries were in the range of 77.1–108.6% at different concentrations for real samples. Compared to previous standard methods for the determination of PAHs and TSNAs in MSS, our method was highly effective, fast, and had low consumption of organic solvent and a high degree of automation. Finally, our method successfully analyzed PAHs and TSNAs in real samples,and no significant deviations were observed when compared to similar analysis using standard methods.

关键词： Silica/primary secondary amine(SiO2/PSA) In-pipette-tip solid phase extraction(SPE) Polycyclic aromatic hydrocarbons(PAHs) Tobacco-specific N-nitrosamines(TSNAs) On-line gel permeation chromatography-gas chromatography/tandem mass spectrometry(on-line GPC-GC–MS~2)

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Persistence of malachite green and leucomalachite green in perch (Lateolabrax japonicus)

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Chinese Journal of Oceanology and Limnology 2011年第3期29卷 647-655页

作者：谭志军邢丽红郭萌萌王洪艳江艳华李兆新翟毓秀 Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences National Center for Quality Supervision and Test of Aquatic Products Jinzhu(Yantai) Food Research and Development Co. Ltd.

The persistence of malachite green (MG), and its metabolite leucomalachite green (LMG), in fish tissues is still unclear, leading to many trade disputes. In this research, we established and evaluated an HPLC method that could detect MG and LMG simultaneously, and then investigated the persistence of these two toxins in the tissues of juvenile perch (Lateolabrax japonicus) post sub-chronic MG exposure at 1.0 mg/L. Exposure lasted for 2 h everyday and was repeated six times. The perch were then placed in MG-free seawater for 100 d to eliminate the toxins. Results show that MG accumulated in the tissues, including the gills, liver, muscle, blood and viscera, and then was metabolized rapidly to LMG. The concentrations of these two toxins increased significantly with the accumulation process. In general, the highest concentrations of MG and LMG in all tissue exceeded 1 000 μg/kg, except for MG in the muscle. The order of accumulation levels (highest to lowest) of MG was gill>blood>liver>viscera>muscle, while that of LMG was liver>blood>gill>viscera>muscle. High levels of MG or LMG could persist for several hours but decreased rapidly during the elimination process. The concentration of LMG was much higher than that of MG during the experiment, especially in the gill, liver and blood. Therefore, the three tissues play important roles in toxin accumulation, biotransformation, and elimination. Although the MG and LMG concentrations in muscle were much lower than in other tissues, the content still exceeded the European minimum required performance limit (MRPL), even after 2 400 h (100 d) of elimination. This demonstrates that it is extremely difficult to eliminate MG and LMG from tissues of perch, and therefore use of these toxins is of concern to public health.

关键词： persistence residues malachite green leucomalachite green perch

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Improvement of wood properties by composite of diatomite and “phenol-melamine-formaldehyde” co-condensed resin

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Journal of Forestry Research 2013年第4期24卷 741-746页

作者： ZHANG Ming XU Yang WANG Shu-liang SHI Jun-you LIU Chang-yu WANG Cheng-yu College of Materials Science and Engineering Northeast Forestry University China Nation center for quality supervision and test of Wood working Machinery Northeast Forestry University Wood Material Science and Engineering Key Laboratory of Jilin Province Beihua University

We improved the overall performance of fast-growing poplar by utilizing a low-cost, effective and simple method. The fast-growing poplar was modified by a vacuum-pressure impregnation method with three types of modification solutions composed of phe- nol-melamine-formaldehyde （PMF） co-condensed resin, diatomite, and 3-aminopropyl （diethoxy） methylsilane. We measured the weight percent gain （WPG）, bulking, leaching, anti-swelling efficiency （ASE）, wa- ter-repellent effectiveness （WRE）, and oxygen index of the modified specimens. All of the wood physical properties, which are beneficial for human uses, were significantly improved by the treatment. We improved various characteristics of wood and the oxygen index of poplar above 48.6% after the modification using diatomite and PMF co-condensed resin.

关键词： Keywords: wood modification phenol-melamine-formaldehydeco-condensed resin artificial fast-growing poplar diatomite

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Bovine HSD17B8 gene and its relationship with growth and meat quality traits

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Science Bulletin 2015年第18期60卷 1617-1621页

作者： Yun Ma Ningbo Chen Fen Li Weiwei Fu Yapeng Han Yanlin Chang Xiangxiang Jiang Junya Li Yueyu Bai Xuxin Tan College of Life Sciences Xinyang Normal University Institute of Animal Science Chinese Academy of Agricultural Sciences Henan Institute of Animal Health supervision Henan center of Animal Products quality Monitoring and test

17 β-Hydroxysteroid dehydrogenase type 8 （HSD17B8） is an important regulator of lipid and steroid metabolism. In the present study, we aimed to assess the effects of HSD17B8 on growth and meat quality traits in cattle. Transcription profile analysis showed that HSD17B8 was primarily expressed in the salpinx, liver, and testis. Meanwhile, we identified three SNPs （SNPI： intron 1-A91G; SNP2： exon 1-A90G; and SNP3： intron 8-A86G） of the bovine HSD17B8 gene and investigated its haplotype frequencies and linkage disequilibrium. The detected SNPs were found associated with growth traits （body weight, body length, height at withers, heart girth, hip width, and average daily gain） in native cattle populations （Nanyang and Jiaxian） as well as the meat quality traits （Warner- Bratzler shear force, rib area, dressing percentage, carcass weight, and backfat thickness） in commercial breeds （Angus, Hereford, Limousin, Luxi, Simmental, and Jinnan）. Our results provided evidence that polymorphisms in the HSD17B8 gene were associated with growth traits and meat quality traits. Moreover, our findings might be used for marker-assisted selection in beef cattle breeding program

关键词： HSD17B8. Polymorphisms Growthand meat quality traits Native Chinese cattle

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test and Evaluation for Coach Forward Collision Warning System

Test and Evaluation for Coach Forward Collision Warning Syst...

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2018中国汽车工程学会年会

作者： NIU Chengyong XU Jianxun YOU Guoping ZHANG Yidong ZENG Jie HU Xiong Chongqing Vehicle test ＆ Research Institute National Bus and Coach Quality Supervision and Test Center

The test and evaluation of a coach FCWS which matched different manufacturers in domestic and international are presented in the national Coach quality Inspection center according to the traffic industry standard JT/T 883—2014 on the basic of introducing the function and working principle of coach vehicle forward collision warning system（FCWS）.Then,the different sensor types of FCWS are analyzed and some relevant suggestion is ***,some problems are given on the coach FCWS performance test and evaluation,which provides the reference for suppliers to further improve the design of the system stability and security.

关键词： coach Forward Collision Warning System(FCWS) test evaluation

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