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Journal of Systematics and Evolution 2010年第5期48卷 309-317页

作者： 1Hong-Bo PANG 2Qing-Wen SUN 2Shun-Zhi HE 1Yin-Zheng WANG 1(State Key laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese Academy of sciences,beijing 100093,china) 2(Guiyang College of Traditional Chinese Medicine,Guiyang 550002,china) (State Key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Guiyang College of Traditional Chinese Medicine Guiyang 550002 China) *Correspondence: Yin-Zheng WANG *Correspondence: ?Author for correspondence. E-mail: wangyz@*** Tel.: 86-10-62836474 Fax: 86-10-62590843.

Tengia has been called a "natural peloria" in the family Gesneriaceae because it exhibits an almost perfect actinomorphic flower from whorl one to whorl *** would be especially interesting to know whether or how CYC-like gene activities are related to this type of perfect actinomorphic *** address this,we have isolated four CYC-like TCP genes and carried out an investigation on their expression patterns in ***1C and TsCYC1D have similar expression patterns with strong signals being detected in all five petals and stamens,whereas TsCYC2A and TsCYC2B are only transiently expressed in the very early floral *** results suggest that the expansion of the expressions of TsCYC1C and TsCYC1D from the dorsal to the ventral petals is likely responsible for the evolutionary formation of the fully dorsalized actinomorphic corolla,that is,an expanded functional domain of CYC-like gene dorsal identity in Tengia ***,the expressions of TsCYC1C and TsCYC1D are not correlated with stamen abortion;therefore,TsCYC genes do not functionally repress the stamen development in Tengia *** is probably due to changed cis-activities that result in the cell cycle-related genes uncoupling from the TsCYC regulatory pathway in Tengia.

关键词： actinomorphy CYCLOIDEA dorsalized Gesneriaceae RNA in situ hybridization Tengia.

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宽量程的气体超声测量

数据采集与处理 2004年第3期19卷 356-360页

作者：顾宇周康源宁晨陈昕中国科学技术大学电子工程与信息科学系合肥230027

研究了一种针对管径和流量变化范围大的气体的超声流量测量系统的设计。利用传统流量计的原理 ,结合微弱信号处理技术和目前先进的 CPLD高频电路设计技术 ,针对高精度、宽量程的要求 ,设计出具有数字 AGC自动增益控制和纠错系统、高频... 详细信息

研究了一种针对管径和流量变化范围大的气体的超声流量测量系统的设计。利用传统流量计的原理 ,结合微弱信号处理技术和目前先进的 CPLD高频电路设计技术 ,针对高精度、宽量程的要求 ,设计出具有数字 AGC自动增益控制和纠错系统、高频计数系统在内的新型气体超声波流量计 ,它还具有主从处理器并行工作结构和多种输出方式。

关键词：流量计气体超声测量微弱信号处理 CPLD 电路设计

INVESTIGATION ON THE VALENCE STATE OF Ce ATOMIN BULK AND NANOCRYSTAL CeO_2 BY X-RAY ABSORPTION ANDPHOTOEMISSION

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 511-516页

作者： K. Ibrahim, Z.Y. Wu, J. Zhang, M.I. Abbas, F.Q. Liu and H.J. Qian (beijing Synchrotron Radiation laboratory, Institute of High Energy Physics, The Chinese Academy of sciences, P.O. Box 918, beijing 100039, china) beijing Synchrotron Radiat. Lab. Inst. of High Energy Phys. Chinese Acad. of Sci. P.O. Box 918 Beijing 100039 China

Valence band photoemission spectra (PES) for both bulk and nanocrystal CeO2 have been measured on and off resonance of Ce 4d-4f absorption edge. The PES show that the bulk and nanocrystal CeO2 of diameter ranging from 8nm to 50nm exhibit a peak near Fermi edge with binding energy of about 1.8eV. The 1.8eV peak shows a strong dependence on excitation energy, although it looks like the contribution of Ce3+ ion following the data reported in literatures. However, according to the results of resonance photoemission and X-ray absorption spectra at 1s edge, this electronic structure may be associated to the intermediate state charge transfer effects.

关键词： rare earth oxide photoemission electronic structure photoabsorption

Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, china

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Pedosphere 2011年第1期21卷 115-123页

作者： SHEN Ye-Na LUE Jun CHEN Ding-Jiang SHI Yi-Ming Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 (China) china Ministry of Education Key Lab of Environmental Remediation and Ecological Health Zhejiang University Hangzhou 310029 (China) Zhejiang Provincial Key laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastern *** on the hydrogeochemical data collected monthly over a period of 3 years,cluster analysis(CA) and principal component analysis(PCA) were adopted to categorize the river reaches and reveal their pollution *** to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments,the whole river system could be categorized into three groups of river reaches,i.e.,non-point sources pollution reaches(NPSPR),urban reaches(UR) and mixed sources pollution reaches(MSPR).In UR and MSPR,the water quality was mainly impacted by nutrient and organic pollution,while in NPSPR nutrient pollution was the main *** nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in *** were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR,while in UR the pollutant concentrations decreased with increasing river *** dry season was the critical period for water pollution control in ***,catchment land covers and human activities had significant impact on river reach water pollution type,nutrient forms and water quality responses to hydrological conditions,which might be crucial for developing strategies to combat water pollution in watershed scale.

关键词： cluster analysis hydrological conditions pollution factors principle component analysis water quality

Effect of commercial AB_5 alloy addition on the electrochemical properties of Ml-Mg-Ni-based hydrogen storage alloys

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Rare Metals 2008年第4期27卷 429-433页

作者： HU Lin HAN Shumin LI Jinhua ZHU Xilin LI Yuan State Key laboratory of Metastable Materials science and technology Yanshan University Qinhuangdao 066004 China College of Environmentaland Chemical Engineering Yanshan University Qinhuangdao 066004 China

A commercial AB5 hydrogen storage alloy was used as an additive to improve the electrochemical properties of Ml-Mg-Ni-based hydrogen storage alloys. The effect of AB5 alloy addition on the phase structure, charge/discharge characteristics, and electrochemical kinetics of Ml0.90Mg0.10Ni3.08Mn0.13Co0.63Al0.14 alloy was investigated. The maximum discharge capacity of Ml0.90Mg0.10Ni3.08Mn0.13Co0.63Al0.14 ＋ 4 wt.% AB5 electrode reaches 406 mAh/g. The anodic polarization, cyclic voltammetry, and potential step discharge experiments show that the electrochemical kinetics of the electrode with additives was promoted, with the LaNi5 phase of AB5 alloy acting as electro-catalytic sites in the electrode alloy. The high-rate dischargeability of Ml0.90Mg0.10Ni3.08Mn0.13Co0.63Al0.14 ＋ 4 wt.% AB5 alloy electrode at 1100 mA/g reaches 60.9%, which is 9.4% higher than that of Ml0.90Mg0.10Ni3.08Mn0.13Co0.63Al0.14 alloy electrode. The cycling stability of the electrode with 4 wt.% AB5 alloy has also been improved

关键词： hydrogen storage alloys additive rare earths electrochemical properties electrochemical kinetics

Effects of Sc content on the mechanical properties of Al-Sc alloys

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Rare Metals 2010年第5期29卷 451-455页

作者： SUN Yingying,SONG Min,and HE Yuehui State Key laboratory of Powder Metallurgy,Central South University,Changsha 410083,china State Key laboratory of Powder Metallurgy Central South University Changsha China

The effects of Sc content on the mechanical properties of Al-Sc alloys were investigated. The results show that the strengths of all the tested alloys with 0.1 wt.%, 0.3 wt.%, and 0.4 wt.% Sc additions increase initially with an increase in annealing time, due to the increase in volume fraction and size and the decrease in particle interspacing of Al3Sc particles. After reaching peak values, the strengths of all the tested alloys start to decrease with increasing annealing time due to the coarsening and increase in particle interspacing of At3Sc particles. It has also been shown that the alloy with 0.3 wt.% Sc has a higher strength and a lower elongation than the alloys with 0.1 wt.% and 0.4 wt.% Sc. The increase in strength and the decrease in elongation of the alloy with 0.3 wt.% Sc are due to the smaller particle interspacing of Al3Sc particles, resulting in a strong inhibition of dislocation movement during deformation.

关键词： aluminum alloys scandium mechanical properties microstructure

Finite automata based on quantum logic and monadic second-order quantum logic

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science china(information sciences) 2010年第1期53卷 101-114页

作者： LI YongMing College of Computer science, Shaanxi Normal University, Xi’an 710062, china 1. College of Computer science Shaanxi Normal University Xi’an 710062 China

We introduce monadic second-order quantum logic and prove that the behaviors of finite automata based on quantum logic are precisely the quantum languages definable with sentences of our monadic secondorder quantum logic. This generalizes Büchi’s and Elgot’s fundamental theorems to quantum logic setting. We also consider first-order quantum logic and show that star-free quantum languages and aperiodic quantum languages introduced here coincide with the first-order quantum definable ones. This generalizes Schützenberger’s fundamental theorems to quantum logic setting. The determinazation of finite automata based on quantum logic is studied by introducing the generalized subset construction method. Then the Kleene theorem in the frame of quantum logic is presented here.

关键词： quantum logic finite automaton monadic second quantum logic quantum language quantum computation Kleene theorem

Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3) Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-Wen XIE~1 Wan-Rong ZHOU~1 1 laboratory of Veterinary and Biotechnology,Sichuan Agricultural University,Ya'an 625014,china 2 Sichuan University Bioengineering Research Center for Animal Disease Prevention and Control,Chengdu 610065,china 3 Faculty of Environment and Resource of Dujiangyan Campus,Sichuan Agricultural University,Dujiangyan 611830,china 4 College of Earth science,Chengd University of technology,Chengdu 610059,china 5 College of Life science,Sichuan Agricultural University,Ya'an 625014,china laboratory of Veterinary and Biotechnology Sichuan Agricultural University Ya'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

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综合交通网中长期发展规划

交通运输系统工程与信息 2008年第1期8卷 17-28页

作者： Department of Transportation of national Development and Reform Commission (Department of Transportation of national Development and Reform Commission,beijing 100824,china) 国家发展和改革委员会交通运输司北京100844

交通运输作为基础产业,对国民经济和社会发展至关重要.改革开放以来,我国交通运输发展迅速,综合交通网络规模不断扩大,网络布局和结构得到改善,设施装备水平较大提高,运输能力显著增强.但从总体上看,交通运输仍然不能适应国民经济和社... 详细信息

交通运输作为基础产业,对国民经济和社会发展至关重要.改革开放以来,我国交通运输发展迅速,综合交通网络规模不断扩大,网络布局和结构得到改善,设施装备水平较大提高,运输能力显著增强.但从总体上看,交通运输仍然不能适应国民经济和社会发展的需要,"瓶颈"制约尚未完全消除,结构性矛盾仍较突出.根据党的十六大提出的全面建设小康社会总体任务,需要加快建立便捷、通畅、高效、安全的综合运输体系,以最小的资源和环境代价满足经济社会对运输的总需求.为明确我国交通基础设施的发展目标和任务,统筹协调各种运输方式,合理配置和有效利用交通运输资源,发挥综合交通的整体优势,国家发展改革委会同有关部门,组织编制了《综合交通网中长期发展规划》.

关键词：综合交通网络发展规划交通规划建设规划