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Diversity and ecological distribution of endophytic fungi associated with medicinal plants

science china(life sciences) 2008年第8期51卷 751-759页

作者： SUN JianQiu1,2,3, GUO LiangDong1, ZANG Wei2,3, PING WenXiang4 & CHI DeFu3 1 Systematic Mycology and Lichenology Laboratory, Institute of Microbiology, Chinese Academy of sciences, Beijing 100101, china 2 college of life science and engineering, qiqihar university, qiqihar 161006, china 3 college of Forestry, Northeast Forestry university, Harbin 150040, china 4 college of life science, Heilongjiang university, Harbin 150080, china 1. Systematic Mycology and Lichenology Laboratory Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China 2. college of life science and engineering Qiqihar University Qiqihar 161006 China 3. college of Forestry Northeast Forestry University Harbin 150040 China 4. college of life science Heilongjiang University Harbin 150080 China

A total of 973 isolates of endophytic fungi were recovered from 1144 tissue fragments of the six me-dicinal plant species belonging to 4 families collected in the Beijing Botanical Garden. Of these isolates 778 sporulated and were identified into 21 taxa by morphological characteristics. Among the taxa 11 belonged to Coelomycetes, 6 to Ascomycetes, and 4 to Hyphomycetes. Various numbers of endophytic fungi (5―8 taxa) were obtained from each plant. Alternaria alternata was the dominant species in the 6 plants, and Microsphaeropsis conielloides was also dominant in Eucommia ulmoides. There were high colonization rates (47.9%―63.1%) and isolation rates (0.7―0.93) of endophytic fungi, and they were conspicuously higher in twigs than those in leaves in the 6 plants examined. The colonization and isolation rates of endophytic fungi increased with the twig age. The results based on the analyses of cluster and Sorenson's similarity coefficients indicated that some endophytic fungi showed a certain degree of host and tissue preference.

关键词： endophytic fungus medicinal plant diversity host and tissue preference

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Degradation of anthracene, pyrene and benzo[a]-anthracene in aqueous solution by chlorine dioxide

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science china Chemistry 2006年第6期49卷 565-572页

作者： LIU Jinquan1, HUANG Junli1, SU Liqiang2, CAO Xiangyu1 & JI Ying1 1. School of Municipal and Environmental engineering, Harbin Institute of Technology, Harbin 150090, china 2. School of Chemistry and Chemical engineering, qiqihar university, qiqihar 161006, china 1. School of Municipal and Environmental engineering Harbin Institute of Technology Harbin 150090 China 2. School of Chemistry and Chemical engineering Qiqihar University Qiqihar 161006 China

Polycyclic aromatic hydrocarbons (PAHs) constitute an important group of micropollutants, which are known to be mutagenic, carcinogenic and/or co-carcinogenic and relatively persistent in the environment. The effects of chlorine dioxide (ClO2) on the degradation of anthracene (ANTH), pyrene (PYR) and benzo[a]anthracene (BaA) in aqueous solution were investigated using high performance liquid chromatography (HPLC). In preliminary experiments, it was observed that ClO2 could remove these three PAHs effectively within a short time. Several factors including reaction time, the concentration of ClO2 and pH of the reaction mixture influencing the degradation ratio of PAHs have been studied by batch experiments. The results showed that the degradation ratio of PAHs was affected by reaction time and the concentration of ClO2 instead of pH. The degradation ratio of ANTH, PYR and BaA could reach their maximum as approximately 99.0%, 67.5% and 89.5%, respectively, under the condition as follows: reaction time 30, 60 and 120 min, the concentration of ClO2 0.1, 0.4 and 0.5 mmol·L-1, and pH 7.2. ANTH was selected as the representative to study the reaction mechanism with ClO2. The oxidation products formed in the reaction of ANTH with ClO2 were tentatively identified by gas chromatography-mass spectrometry (GC-MS), and the results showed that the main product was 9, 10-anthraquinone, which could be biodegraded more easily and quickly than ANTH. Through analyzing the reaction properties of ANTH and ClO2, the possible pathway for the ANTH-ClO2 reaction was proposed based on the theory of single electron transfer (SET).

关键词： chlorine dioxide, anthracene, pyrene, benzo[a]anthracene, degradation, reaction mechanism.

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Generalized dromion solutions of a new higher dimensional soliton equation

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Communications in Nonlinear science and Numerical Simulation 2001年第2期6卷 97-101页

作者： Jiefang ZHANG and Gongdi XU Shanghai Institute of Applied Mathematics and Mechanics, Shanghai 200072, china Institute of Nonlinear Physics, Zhejiang Normal university, Jinhua 321004, china college of Chemical engineering, qiqihar university, qiqihar 161 Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China college of Chemical engineering Qiqihar University Qiqihar161000 China

We derive the generalized dromions of the new higher dimensional soliton equation by suitably utilizing the arbitrary function present in the bilinearized linear equations. The rich dromion structures for this system ... 详细信息

关键词： dromion soliton equation

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Structures and stability of isomers of[C,N,N,P]system

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science china Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2, ZHONG Hua1, YU Haitao1, FU Honggang1,3 & SUN Jiazhong1,3 1. School of Chemistry and Materials science, Heilongjiang university, Harbin 150080, china 2. School of Chemistry and Chemical engineering, qiqihar university, qiqihar 161006, china 3. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 130023, china 1. School of Chemistry and Materials science Heilongjiang University 150080 Harbin China 2. School of Chemistry and Chemical engineering Qiqihar University 161006 Qiqihar China 3. Jilin university State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2A′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

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Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic engineering college, Shandong Agricultural university, Tai’an 271018, china 2 college of Materials science and engineering, university of science and Technology, Beijing 100083, china 3 college of Material science and engineering, Beijing university of Chemical Technology, Beijing 100029, china Mechanical Electronic engineering college Shandong Agricultural University Tai’an 271018 China college of Materials science engineering University of Science Technology Beijing 100083 China college of Material science engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

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Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2, LIU Ping2, DONG Qiming2 & LI Hejun1 1. college of Materials science and engineering, Northwestern Polytechnical university, Xi’an 710072, china 2. college of Materials science and engineering, Henan university of science and Technology, Luoyang 471003, china 1. college of Materials science and engineering Northwestern Polytechnical University 710072 Xi’an China 2. college of Materials science and engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

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GENETIC DIVERSITY OF SOME BRYOPHYTES IN NORTHEAST china

GENETIC DIVERSITY OF SOME BRYOPHYTES IN NORTHEAST CHINA

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中国苔鲜植物学奠基人陈邦杰先生百年诞辰国际学术研讨会

作者： Wei Sha Jing Li (Department of Biology college of life science and engineering qiqihar university qiqihar 161006)

＜正＞This is a study on the genetic diversity of some large bryophytes in northeast china. These aspects which were the handle of 20 species of bryophyte material, the genomic DNA extracts, the establish of the RAPD ... 详细信息

关键词： Bryophytes Genetic diversity Molecular systematics

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Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 Department of Materials science and engineering,Nanjing university of science and Technology,Nanjing 210094,china 2 college of Materials science and engineering,Southeast university,Nanjing 211189,china 1. Department of Materials science and engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

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STUDY OF GENETIC DIVERSITY IN TWO SPECIES OF GRIMMIACEAE

STUDY OF GENETIC DIVERSITY IN TWO SPECIES OF GRIMMIACEAE

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中国苔鲜植物学奠基人陈邦杰先生百年诞辰国际学术研讨会

作者： Wei Sha Han Zhang (Department of Biology college of life science and engineering. qiqihar university qiqihar 161006)

＜正＞Sixty individuals of six populations of Grimmiaceae were analyzed by random amplified polymorphic DNA （RAPD） markers, to determine the genetic variations among and within populations. A total of 52 loci were a... 详细信息

关键词： Grimmiaceae RAPD Genetic diversity

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Boundary conditions for the bending of a piezoelectric beam

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of science, china Agricultural university, Beijing 100083, china 2 college of engineering, Ocean university of china, Qingdao 266071, china 3 School of Mechanical engineering, university of science and Technology Liaoning, Anshan 114044, china 1. college of science China Agricultural University Beijing 100083 China 2. college of engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

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