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Rice Mitochondrial Genes Are Transcribed by Multiple Promoters That Are Highly Diverged

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Journal of Integrative Plant Biology 2006年第12期48卷 1473-1477页

作者： Qun-yu zhang yao-Guang Liu Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong College of Life Sciences South China Agricultural University Guangzhou 510642 China

Plant mitochondrial genes are often transcribed into complex sets of mRNA. To characterize the transcription initiation and promoter structure, the transcript termini of four mitochondrial genes, atpl, atp6, cob, rps7, in rice （Oryza sativa L.）, were determined by using a modified circularized RNA reverse transcription- polymerase chain reaction method. The results revealed that three genes （atp1, atp6, rps7） were transcribed from multiple initiation sites, indicating the presence of multiple promoters. Two transcription termination sites were detected in three genes （atp6, cob, rps7）, respectively. Analysis on the promoter architecture showed that the YRTA （Y=T or C, R=A or G） motifs that are widely present in the mitochondrlal promoters of other monocot and dicot plant species were detected only in two of the 12 analyzed promoters. Our data suggest that the promoter sequences in the rice mitochondrial genome are highly diverged in comparison to those in other plants, and the YRTA motif is not an essential element for the promoter activity.

关键词： mitochondrial gene promoter rice transcription initiation site transcription termination site

Soil Enzyme Activities with Greenhouse Subsurface Irrigation

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Pedosphere 2006年第4期16卷 512-518页

作者： zhang yu-Long WANG yao-Sheng College of Land and Environmental Sciences Shenyang Agricultural University Shenyang 110161 （China）

Various environmental conditions determine soil enzyme activities, which are important indicators for changes of soil microbial activity, soil fertility, and land quality. The effect of subsurface irrigation scheduling on activities of three soil enzymes (phosphatase, urease, and catalase) was studied at five depths (0-10, 10-20, 20-30, 30-40, and 40-60 cm) of a tomato greenhouse soil. Irrigation was scheduled when soil water condition reached the maximum allowable depletion (MAD) designed for different treatments (-10, -16,-25,-40, and-63 kPa). Results showed that soil enzyme activities had significant responses to the irrigation scheduling during the period of subsurface irrigation. The neutral phosphatase activity and the catalase activity were found to generally increase with more frequent irrigation (MAD of -10 and -16 kPa). This suggested that a higher level of water content favored an increase in activity of these two enzymes. In contrast, the urease activity decreased under irrigation, with less effect for MAD of -40 and -63 kPa. This implied that relatively wet soil conditions were conducive to retention of urea N, but relatively dry soil conditions could result in increasing loss of urea N. Further, this study revealed that soil enzyme activities could be alternative natural bio-sensors for the effect of irrigation on soil biochemical reactions and could help optimize irrigation management of greenhouse crop production.

关键词： irrigation scheduling soil enzyme activity subsurface irrigation tomato

Mixed H_2/H_∞ filtering for a class of high-speed sampling uncertain systems

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Science in China(Series F) 2008年第5期51卷 560-570页

作者： zhang Rui yao yu MA KeMao CHEN SongLin Control and Simulation Center Harbin Institute of Technology Harbin 150001 China

The problem of mixed H2/H∞ filtering for polytopic Delta operator systems is investigated. The aim is to design a linear asymptotically stable filter which guarantees that the filtering error system has different performances in different filtering channels. Based on a parameter-dependent Lyapunov function, a new mixed H2/H∞ performance criterion is presented. Upon this performance criterion, a sufficient condition for the full-order mixed H2/H∞ filter is derived in terms of linear matrix inequalities. The filter can be obtained from the solution of a convex optimization problem. The proposed filter design procedure is less conservative than the strategy based on the quadratic stability notion. A numerical example is given to illustrate the feasibility of the proposed approach.

关键词： H2/H∞ filtering linear matrix inequality polytopic uncertainty

Mei Symmetry and Mei Conserved Quantity for a Non-holonomic System of Non-Chetaev's Type with Unilateral Constraints in Nielsen Style

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Communications in Theoretical Physics 2009年第7期52卷 7-11页

作者： CUI Jin-Chao JIA Li-Qun zhang yao-yu School of Science Jiangnan University Wuxi 214122 China Electric and Information Engineering College Pingdingshall University Pingdingshan 467002 China

Mei symmetry and Mei conserved quantity for a non-holonomic system of non-Chetaev's type with unilateralconstraints in the Nielsen style are *** differential equations of motion for the system above are *** definition and the criteria of Mei symmetry,conditions,and expressions of Mei conserved quantity deduced directlyfrom the Mei symmetry are *** example is given to illustrate the application of the results.

关键词： Nielscn stylc unilatcral constraint non-holonomic system of non-Chctaev's type Mci conscrvcd quantity

An unexpected Hoffmann elimination during the alkylation of dihydrotetrabenazine

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Chinese Chemical Letters 2010年第11期21卷 1334-1337页

作者： zhang yu yao Hao zhang Huan Ming Sheng Xiao Ming Wu Hong Bin Sun Center for Drug Discovery College of PharmacyChina Pharmaceutical UniversityNanjing 210009China

Dihydrotetrabenazine(DTBZ) is the major pharmacologically active form of tetrabenazine(TBZ),which was approved by FDA for the treatment of chorea associated with Huntington’s disease(HD).An unexpected Hoffmann elimination was observed during the treatment of DTBZ with sodium hydrogen and alkyl halides,leading to the formation of both eliminated products(major) and hydroxyl-alkylated products(minor).

关键词： Tetrabenazine Dihydrotetrabenazine Alkylation Hoffmann elimination

Structural Equation and Mei Conserved Quantity of Mei Symmetry for Appell Equations in Holonomic Systems with Unilateral Constraints

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Communications in Theoretical Physics 2009年第10期52卷 572-576页

作者： JIA Li-Qun zhang yao-yu CUI Jin-Chao LUO Shao-Kai School of Science Jiangnan University Wuxi 214122 China Electric and Information Engineering College Pingdingshan University Pingdingshan 467002 China Institute of Mathematical Mechanics and Mathematical Physics Zhejiang Sci-Tech University Hangzhou 31001 China

Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomie mechanic systems with unilateral constraints axe established. The definition and the criterion of Mei symmetry for Appell equations in holonomic systems with unilateral constraints under the infinitesimal transformations of groups axe also given. The expressions of the structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results.

关键词： holonomic system with unilateral constraints Appell equation structural equation of Mei symmetry Mei conserved quantity

Synthesis and Photovoltaic Properties of Non-fullerene Solution Processable Small Molecule Acceptors

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Chemical Research in Chinese Universities 2013年第3期29卷 596-599页

作者： LI Hui LIU Zhao-yang zhang Xiao-yu yao Shi-yu WEN Shan-peng TIAN Wen-jing State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun 130012 P. R. China

Two non-fullerene small molecules, BT-C6 and BT-C12, based on the vinylene-linked benzothiadiazole-thiophene（BT） moiety flanked with 2-（3,5,5-trimethylcyclohex-2-en-l-ylidene）malononitrile have been synthesized and characterized by solution/thin film UV-Vis absorption, photoluminescence（PL）, and cyclic voltammetry（CV） measurements. The two molecules show intense absorption bands in a wide range from 300 nm to 700 nm and low optical band- gaps for BT-C6（1.60 eV） and for BT-C12（1.67 eV）. The lowest unoccupied molecular orbital（LUMO） levels of both the molecules are relatively higher than that of [6,6]-phenyl C61 butyric acid methyl ester（PCBM）, promising high open circuit voltage（Voc） for photovoltaic application. Bulk heterojunction（BHJ） solar cells with poly（3-hexylthiophene）（P3HT） as the electron donor and the two molecules as the acceptors were fabricated. Under 100 mW/cm2 AM 1.5 G illumination, the devices based on P3HT：BT-C6（1：1, mass ratio） show a power conversion efficiency（PCE） of 0.67%, a short-circuit current（Jsc） of 1.63 mA/cm2, an open circuit voltage（Vow） of 0.74 V, and a fill factor（FF） of 0.56.

关键词： Non-fullerene small molecule Electron acceptor Bulk heterojunction

Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 309-320页

作者： yao Jia Jianping Lai Jiaxin yu Huimin Qi Yafeng zhang Hongtu He Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education State Key Laboratory of Environment-Friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China

Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further *** plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical *** this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment ***,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B *** was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B *** heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase ***,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated ***,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological *** finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields.

关键词： Electroless coating Titanium alloy Tribology Wear Heat treatment Nanoindentation

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang Xu Ying-Nan Zhao yao yu Qi Yang Li-Hua Na Heng Liu Chun-yu zhang Xue-Quan zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity