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Cloning, bioinformatics and transcriptional analysis of caffeoyl-coenzyme A 3-O-methyltransferase in switchgrass under abiotic stress

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Journal of Integrative Agriculture 2016年第3期15卷 636-649页

作者： LIU Si-jia HUANG Yan-hua he chang-jiu FANG Cheng ZHANG Yun-wei Department of Grassland Science College of Animal Science and Technology China Agricultural University/National Energy R&D Center for Biomass (NECB) Key Laboratory of Animal Genetics and Breeding Ministry of Agriculture/National Engineering Laboratory for Animal Breeding College of Animal Science and Technology China Agricultural University

Genes encoding enzymes involved in the lignin biosynthesis through phenylpropanoid pathway were not only associated with the lignin content, but also related to the abiotic stress resistances. As far as the production of liquid biofuels and cultivation within the marginal land are concerned, switchgrass could be the better candidate to determine the relationship between lower lignin content and physiological function under stress. Caffeoyl-coenzyme A 3-O-methyltransferase（CCoAOMT） is a key enzyme for the methylation reaction of lignin biosynthesis. For this purpose, we cloned a CCoAOMT gene from switchgrass and identified its expression patterns under abiotic stresses. The full-length CCoAOMT gene, designated PvCCoAOMT（Gen Bank accession no. KF041775）, was 1 005-bp in length, has an opening reading frame of 777 nucleotides encoding a 258-amino acid protein. The deduced amino acid sequence of PvCCoAOMT shared a high degree of similarity（up to 98%） with CCoAOMTs from Panicum virgatum allele（BAO20881）, Sorghum bicolor（XP002436550） and Zea mays（NP001131288）. Using quantitative real-time PCR（qRT-PCR）, the significant upregulation of PvCCoAOMT was observed in stem tissues at a later stage（24 h） after drought treatment, with the transcript level increasing 33-fold compared that of the controls. Moderate and insignificant inductions of PvCCoAOMT were also observed in both stems and leaves during the later stages after cold（48 h in stems, 12 h in leaves） and mechanical wounding（48 h in stems, 12 h in leaves） treatments, respectively. Our results showed the different expression patterns of PvCCoAOMT in drought, cold and mechanical wounding stresses. PvCCoAOMT can be highly induced by drought and cold stresses, which indicates that it may play a role in plant abiotic stress resistance, particularly in the regulation of drought and cold resistance.

关键词： Panicum virgatum phenylpropanoid drought resistance biofuel production real-time PCR

CBN grain wear and its effects on material removal during grinding of FGH96 powder metallurgy superalloy

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Advances in Manufacturing 2023年第1期11卷 21-38页

作者： Ben-Kai Li Biao Zhao Wen-Feng Ding Yu-Can Fu chang-he Li Rong Wang Yan-Jun Zhao National Key Laboratory of Science and Technology on helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266525ShandongPeople’s Republic of China Aecc Xi’an Aero-engine Ltd Xi’an710021People’s Republic of China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasive and GrindingZhengzhou450001People’s Republic of China

Grinding with cubic boron nitride(CBN)superabrasive is a widely used method of machining superalloy in aerospace ***,there are some issues,such as poor grinding quality and severe tool wear,in grinding of powder metallurgy superalloy *** addition,abrasive wheel wear is the significant factor that hinders the further application of CBN abrasive *** this case,the experiment of grinding FGH96 with single CBN abrasive grain using different parameters was carried *** wear characteristics of CBN abrasive grain were analyzed by experiment and *** material removal behavior affected by CBN abrasive wear was also studied by discussing the pile-up ratio during grinding *** shows that morphological characteristics of CBN abrasive grain and grinding infeed direction affect the CBN abrasive wear seriously by simulation *** wear,micro break,and macro fracture had an important impact on material removal ***,compared with the single cutting edge,higher pile-up ratio was obtained by multiple cutting edges,which reduced the removal efficiency of the ***,weakening multiple cutting edge grinding on abrasive grains in the industrial production,such as applying suitable dressing strategy,is an available method to improve the grinding quality and efficiency.

关键词： FGH96 powder metallurgy superalloy Single-grain grinding Cubic boron nitride(CBN)abrasive wear Material removal behavior

simultaneous determination of vitexin-2"-O-glucoside,vitexin-2"-O-rhamnoside,rutin,vitexin,and hyperoside by HPLC

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Journal of Pharmaceutical Analysis 2011年第4期1卷 291-296页

作者： chang-he Wang Yu-Xuan Wang Hai-Jing Liu Shaanxi Institute for Food and Drug Control Xi＇an 710061 China Shaanxi University of Chinese Medicine Xianyang 712046 China

A simple, precise, and rapid high-performance liquid chromatographic method was developed and validated for the simultaneous determination of vitexin-2＂-O-glucoside, vitexin-2＂-O-rhamnoside, rutin, vitexin, and hyperoside. The HPLC separation was performed using a Shim-pack VP-ODS C18 column （250 mm ~ 4.6 mm i.d., 5 ~tm） with the isocratic mobile phase consisting of tetrahydrofuran/ acetonitrile/0.05% phosphoric acid solution （20：3：77, v/v/v）, and the flow rate was set at 1.0 mL/min. UV detection was carried out at a wavelength of 360 nrn and the whole analysis took 25 min. The method was linear in the range of 4.12-206.00 μg/mL for vitexin-2＂-O-glucoside, 4.05-202.50 μg/mL for vitexin-2＂-O- rhanmoside, 1.64-82.00 pμg/mL for rutin, 1.74-87.00 gg/mL for vitexin, and 1.41-70.60 p.g/mL for hyperoside with the correlation coefficient for each analyte more than 0.998. The limit of detection （LOD） and limit of quantitation （LOQ） were 0.6 and 2 ng for vitexin-2＂-O-glucoside, 0.6 and 2 ng for vitexin-2＂-O-rhamnoside, 0.3 and 1 ng for rutin, 1 and 3 ng for vitexin, and 0.5 and 2 ng for hyperoside, respectively. Intra- and inter-day precision and accuracy （RSD） were less than 3%. The developed HPLC method was successfully applied to the analysis of five flavonoids in hawthorn leaves, hawthorn fruits, and the preparations containing hawthorn leaves or fruits.

关键词： High-performanceliquid chromatography Flavonoids Hawthorn Leaves and fruits Preparations

Photorefractive Holographic Dynamics in Doubly Doped LiNbO_(3):Fe:Mn

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Chinese Physics Letters 2000年第8期17卷 571-573页

作者： Liu You-wen LIU Li-ren ZHOU chang-he XU Liang-Ying Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050

The Kukhtarev two-center model for photochromic doubly doped LiNbO_(3):Fe:Mn crystals is both numerically and analytically solved for the recording sensitivity and the fixed nonvolatile space-charge *** optimal prescription for material doping and oxidation/reduction processing is found,which requires that the crystal should be strongly oxidized together with a suitable Mn density with respect to the Fe *** performed with an oxidized crystal and a reduced crystal prove the prediction.

关键词： density field crystal

Raman scattering study of two-dimensional magnetic van der Waals compound VI3

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Chinese Physics B 2020年第5期29卷 420-423页

作者： Yi-Meng Wang Shang-Jie Tian Cheng-he Li Feng Jin Jian-Ting Ji he-chang Lei Qing-Ming Zhang Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China

The layered magnetic van der Waals materials have generated tremendous interest due to their potential applications and importance in fundamental *** x-ray diffraction(XRD)studies on the magnetic van der Waals compound VI3,revealed a structural transition above the magnetic transition but output controversial analysis on *** this paper we carried out polarized Raman scattering measurements on VI3 from 10 K to 300 K,with focus on the two Ag phonon modes at^71.1 cm^-1 and 128.4 *** careful symmetry analysis based on the angle-dependent spectra demonstrates that the crystal symmetry can be well described by C2h rather than D3d both above and below structural phase *** further performed temperature-dependent Raman experiments to study the magnetism in *** asymmetry and anomalous linewidth drop of two Ag phonon modes at low temperatures,point to a significant spin-phonon *** is also supported by the softening of 71.1-cm^-1 mode above the magnetic *** study provides the fundamental information on lattice dynamics and clarifies the symmetry in *** spin-phonon coupling existing in a wide temperature range revealed here may be meaningful in applications.

关键词： Raman scattering two-dimensional magnetic van der Waals materials lattice dynamics magnetism

Polymer Photovoltaic Cells

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复旦学报（自然科学版） 2005年第5期44卷 717-718页

作者： Jianhui Hou Chunhe Yang Erjun Zhou chang he Zhan＇ ao Tan Youjun he Yongfang Li CAS Key Laboratory of Organic Solids Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Polymer photovoltaic cells (PPVCs) have attracted much attention recently because of its easy fabrication, low cost and possibility to make flexible devices[1]. PPVC is composed of a conjugated polymer/C60blend layer (photosensitive layer) sandwiched between a transparent ITO electrode and a metal *** a light through ITO electrode irradiates on the photosensitive layer, the photons with appropriate energy will be absorbed by the conjugated polymer (CP) and excitons (electron-hole pair) are produced. The excitons move to the interface of CP/C60 where the electrons transfer to the LUMO of C60 and holes leave on the HOMO of the CP. The separated electrons migrate through the C60 network to and are collected by the metal electrode, and the holes migrate through the CP network to and are collected by the ITO electrode, so that the photocurrent and photovoltage are attained.

关键词：光电电池共轭聚合体太阳能电池电极电解液

Optimizing polymer aggregation and blend morphology for boosting the photovoltaic performance of polymer solar cells via a random terpolymerization strategy

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Journal of Energy Chemistry 2021年第8期30卷 30-37,I0002页

作者： Tao Zhang Cunbin An Qianglong Lv Jinzhao Qin Yong Cui Zhong Zheng Bowei Xu Shaoqing Zhang Jianqi Zhang chang he Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences100190 BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology100190 BeijingChina

Compared to regular conjugated polymers,the random conjugated terpolymers are usually not beneficial to achieve highly efficient non-fullerene(NF)-based polymer solar cells(PSCs)due to their disordered chemical *** this work,we report two random terpolymer donors(PBNB80 and PBNB50)by tuning the molar ratio of electron-accepting units of 1,3-di(thiophen-2-yl)naphtho[2,3-c]thiophene-4,9-dione(NTD)and 1,3-bis(4-chlorothiophen-2-yl)-4 H,8 H-benzo[1,2-c:4,5-c’]dithiophene-4,8-dione(ClBDD),at the same time,the parent polymers(PBNB100 and PBNB00)are also compared to *** four polymer donors exhibit similar optical bandgaps and gradually deepen highest occupied molecular orbital ***,aggregation and self-organization properties of the random terpolymer donors are optimized,which result in the better morphology and crystal coherence length after blending with NF acceptor of BO-4 ***,a PBNB80:BO-4 Cl blend forms an optimal nanoscale phase-separation morphology,thereby producing an outstanding power conversion efficiency of 16.0%,which is much higher than those(12.8%and 10.7%)of their parent binary polymer donor-based *** work demonstrates that rational using terpolymerization strategy to prepare random terpolymer is a very important method to achieve highly efficient NF-PSCs.

关键词： Polymer solar cells Random terpolymer Non-fullerene acceptor Naphtho[2,3-c]thiophene-4,9-dione Morphology

Molecular characteristics and stages of chronic hepatitis B virus infection

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World Journal of Gastroenterology 2009年第25期15卷 3099-3105页

作者： Ying-Hui Shi chang-he Shi Department of Microbiology Centers for Disease Control and Prevention of Qingdao Qingdao 266034 Shandong Province China Department of hepatitis Qingdao Infectious Disease Hospital Qingdao 266033 Shandong Province China

hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B eantigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants.

关键词： hepatitis B virus Pathology Immune tolerance Immune clearance Inactive hepatitis B surface antigen carriers Reactivation T-cell response Cytokines

“高分子物理”课程教学中进行完整数学推导举隅

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高分子材料科学与工程 2010年第12期26卷 173-175页

作者：贺昌城北京师范大学化学学院

高分子物理课程中有许多内容是进行公式或结论的数学推导。这些数学推导及其结果或结论,对于人们认识高分子的结构本质,理解和把握聚合物本体及其二元或多元宏观体系的结构、性质与变化规律等有着重要作用。在课堂教学中,教师应力求使... 详细信息

高分子物理课程中有许多内容是进行公式或结论的数学推导。这些数学推导及其结果或结论,对于人们认识高分子的结构本质,理解和把握聚合物本体及其二元或多元宏观体系的结构、性质与变化规律等有着重要作用。在课堂教学中,教师应力求使推导过程严密完整,如此有助于提高本门课程的教学效果。文中以自由连接链均方末端距的推导和聚合物/溶剂体系高临界溶解温度(UCST)的相分离临界条件推导计算为例,阐述在高分子物理课程教学中如何借助数学工具进行完整数学推导。

关键词：高分子物理数学推导教学研究均方末端距相分离