检索结果-南通市图书馆

Science china chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2. LIU ZhongFang1 & LIU ShaoPu1 1 School of chemistry and Chemical Engineering, Southwest university, {2. 400715, china 2.Department of chemistry, fuling normal university, chongqing 408000, china School of chemistry and Chemical Engineering Southwest UniversityChongqing400715China Department of chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 3.1 nm for ctDNA and sDNA,3.0nm for hsDNA,3.0 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3.sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

Entire vectors for unbounded normal operators and abstract Cauchy problems

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1997年第15期42卷 1253-1256页

作者： LI YangrongDepartment of Mathematics, Southwest normal university, {2. 63.715,{3. Department of Mathematics Southwest Normal University Chongqing China

LET A be a closed operator on a Banach space X, and C~∞ (A)=∩_n~∞=1,D(A^n). The C~∞ vec-tor x is an entire vector for A if sum from n=0 to ∞ (t^n)/(n!)||A^n x||0. We will write ε(A) for the set of all entire vectors for A. It is well known that the set of entire vectors for a self-adjoint operator is dense. Inthis note, we generalize this result to the situation of (unbounded) normal operators. We

关键词： C-semigroups analytic semigroups normal operators entire vectors.

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

在线全文

学校读者我要写书评

暂无评论

Science china chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2. LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of chemistry and Molecular Engineering, Peking university, Beijing 100871,{2. 2. Institute of chemistry, Chinese Academy of Sciences, Beijing 100080,{2. 3. Department of Surgery, Third Hospital, Peking university, Beijing 100083.{2. 4. Department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061,{2. Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. Department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of chemistry Chinese Academy of Sciences 100080 Beijing China 4. Department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3.0}normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2. which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

在线全文

学校读者我要写书评

暂无评论

Science china chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. Department of chemistry, Southwest-{3. {2. university, chongqing 400715, china 2. Department of chemistry, Sichuan university, Chengdu 610064, china 1. Department of chemistry Southwest-China Normal University Chongqing 400715 China 2. Department of chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3.YP/6-3.g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Study on Green Residential Space Design

在线全文

学校读者我要写书评

暂无评论

IJLAI Transactions on Science and Engineering

IJLAI Transactions on Science and Engineering 2024年第1期2卷 32-37页

作者： Yu Jiang Shenyang normal university No.2.3.Huanghe North Street Shenyang 110034China

With the ever-changing nature,green ecology has become an international trend of ***,the green ecological design of residential space has become the main melody of people’s *** always implement the concept of ecological and environmental protection in the design process,attach importance to the ecological effect of residential space,carry out reasonable budget and use of environmentally friendly decorative materials,reduce the waste of materials,save money and save resources at the same time,and protect the *** the same time,people began to put their hopes on the residential space design,which made the green residential space design began to *** the bold exploration and practice of designers,the design of green residential space will be endowed with more distinctive characteristics and unique *** from the concept of green design,this paper explores the method of green space design through typical analysis.

关键词： Green Residential space Haze

Theoretical study on the reaction mechanism of(CH_3._3.O+CO

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2.3. SUN Chengke1,4, ZHANG Rongchang3. XI Hongmin3.& LI Zonghe1 1. Department of chemistry, Beijing normal {2., Beijing 100875, china 2. The Laboratory of Molecular Reaction Dynamics, Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, china 3. Department of chemistry, Beihua {2., Jilin 13.0}13. china 4. Department of chemistry, Qujing normal {2., Yunnan 655000, china 1. Department of chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. Department of chemistry Beihua University 132013 Jilin China 4. Department of chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3.3.O with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3.YP/6-3.G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-3.++G** level. The results show that the reaction is multi-channel and the reaction of (CH3.3.O radical with CO mostly produces (CH3.3. + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3.YP, (CH3.3.O, radical.

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2.with DNA and its analytical application

在线全文

学校读者我要写书评

暂无评论

Science china chemistry 2010年第3期53卷 618-624页

作者： LIU JiangTao1,LIU ShaoPu2.& LIU ZhongFang2.1School of chemistry,{3. {2. university,{3. 4003.0,china 2.chool of chemistry and Chemical Engineering,Southwest university,{3. 400715,china School of chemistry Chongqing Normal University Chongqing China School of chemistry and Chemical Engineering Southwest University Chongqing China

The forming of bleomycinA2.Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2.BLMA2. can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2.with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2.Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2.was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2.Cu(Ⅱ) as RRS probe has been *** detection limits(3.) are 7.2.ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching

Superconductivity of small metal grains

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3.1. Department of Physics, Shanghai normal university, Shanghai 2.02.4,{2. 2. Department of Physics, Southwest normal university, chongqing 400715,{2. 3. Department of Computer and Electric Technology, Shanghai Business School, Shanghai 2.1400,{2. 1. Department of Physics Shanghai Normal University 200234 Shanghai China 2. Department of Physics Southwest Normal University 400715 Chongqing China 3. Department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Radiobiological response of human hepatoma and normal liver cells exposed to carbon ions generated by Heavy Ion Research Facility in Lanzhou

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 72-76页

作者： YANG Jianshe1,2. LI Wenjian1, JIN Xiaodong1, JING Xigang1, GUO Chuanling1, WEI Wei1 & GAO Qingxiang3.1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Life Science School of North West {3. {2., Lanzhou 73.070, china 3. Life Science School of Lanzhou {2., Lanzhou 73.000, china 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Life Science School of North West normal university Lanzhou 730070 China 3. Life Science School of Lanzhou university Lanzhou 730000 China

Human hepatoma and normal liver cells were irradiated with 12.6+ ion beams (LET = 96.05 keV/μm) and γ-rays at Heavy Ion Research Facility in Lanzhou (HIRFL). The chromatid breaks and break types were detected using the premature chromosome con- densation technique. Our experimental results showed that chromatid breaks seem to have a good relation with 12.6+ absorbed dose and 12.6+ are more effective to induce chromatid breaks as compared to the γ-rays. For 12.6+ ion irradiation the major break was isochromatid break, while chromatid breaks were dominant for γ-ray irradiation. We also observed that the Relative Biology Effectiveness (RBE) of 12.6+ ion is about 2.5 times higher than that of γ-rays.

关键词： biological response, tumor cell, normal cell, heavy ion HIRFL.

Scenario simulation and forecast of land use/cover in northern china

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3.& HE ChunYang 3.1 College of Geographical Science, chongqing normal {2., chongqing 400047, china 2.College of Resources and Environmental Science, chongqing {2., chongqing 400044, china 3.College of Resources Science & Technology, Beijing normal {2., Beijing 100875, china College of Geographical Science Chongqing Normal University Chongqing 400047 China College of Resources and Environmental Science Chongqing University Chongqing 400044 China College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学