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Journal of Systematics and Evolution 2010年第6期48卷 455-463页

作者： 1,2Lei MENG 2Xiang-Yun ZHU 1(college of Biological sciences,china agricultural university,beijing 100094,china) 2(Institute of Botany,Chinese Academy of sciences,beijing 100093,china) (college of Biological sciences China Agricultural University Beijing 100094 China) (Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The pollen morphology of 11 species of the genus Glycyrrhiza *** one from each of the genera Glycyrrhizopsis Boiss.& *** Meristotropis Fisch.& *** investigated by scanning electron *** pollen morphology,the main differences between Glycyrrhizopsis and Glycyrrhiza are:Glycyrrhizopsis-pollen grains 36.63 × 40.42 μm in size,oblate spheroidal in shape;and Glycyrrhiza-pollen grains 24.47-33.18 × 23.82-31.83 μm in size,prolate spheroidal in *** and Glycyrrhiza should be recognized as two distinct genera based on palynological and morphological *** and Glycyrrhiza are similar in many important palynological and morphological characters,suggesting that the two should be *** Glycyrrhiza,two types of pollen grains,3-lobed-circular or subtriangular in polar view,are found in different species,in accordance with morphological differences in the two groups,shedding light on the classification and evolution of the genus.

关键词： exine sculpture morphological character pollen morphology taxonomic revision.

Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

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science china(Life sciences) 2007年第6期50卷 766-772页

作者： GAO Feng1, HOU XianZhi1 & LIU YingChun2 1 college of animal science and animal Medicine, Inner Mongolia agricultural university, Huhhot 010018, china 2 college of Biotechnology and Bioengineering, Inner Mongolia agricultural university, Huhhot 010018, china college of animal science and animal Medicine Inner Mongolia Agricultural University Huhhot China college of Biotechnology and Bioengineering Inner Mongolia Agricultural University Huhhot China

This study investigated the effects of hormonal status; metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth; development. One hundred Mongolian ewes, synchronized for oestrus; mated, were divided into three groups; offered 0.175 MJME·kgw[0.75]·d[1] (Restricted Group 1, RG1), 0.33 MJME·kgw[0.75]·d[1] (Restricted Group 2, RG2); ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the supply of exogenous energy decreasing during late pregnancy, maternal body weight; net body weight loss in RG2; RG1 were lower than those of CG (Ps0.01). The insulin; IGF-1 concentrations of ewes in RG2; RG1 tended to be lower than those of CG (P>0.05), but the GH concentrations in RG2; RG1 were enhanced; there was significant difference between RG1; CG on d 120 of gestation (P0.05). However, the NEFA; FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 140 of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological; biochemical maternal reactions to restriction became worse, which significantly reduced the average lamb birth weight; daily growth rate of fetus in RG2 (P<0.05); RG1 (P<0.01).

关键词： late pregnancy restricted ewes fetus growth development

The structural analysis of fuzzy measures

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science china(Information sciences) 2011年第1期54卷 38-50页

作者： ZHANG Ling1,ZHANG Bo2 & ZHANG YanPing1 1 Computer science college,Anhui university,Hefei 230039,china 2State Key Lab of Intelligent technology & Systems Tsinghua National Lab for Information science & technology Information science & technology college,Computer science & technology,Tsinghua university,beijing 100084,china Computer science college Anhui University Hefei China State Key Lab of Intelligent technology & Systems Tsinghua National Lab for Information science & technology Information science & technology college Computer Science & Technology Tsinghua University Beijing China

From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an"isotropism"*** this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2)the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3)the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy *** results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures.

关键词： quotient space fuzzy set fuzzy measure rough set structural analysis

Preparation and characterization of poly(vinylidene fluoride) composite membranes blended with nano-crystalline cellulose

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Progress in Natural science:Materials International 2012年第3期22卷 250-257页

作者： Haolong Bai, Xuan Wang, Yitong Zhou, Liping Zhang college of Material science and technology, beijing Forestry university, beijing 100083, china college of Material science and technology Beijing Forestry University Beijing 100083 China

Poly(vinylidene fluoride) (PVDF) composite membranes blended with nano-crystalline cellulose (NCC) for ultrafiltration were prepared by a Loeb-Sourirajan (L-S) phase inversion process. The effects of NCC concentration on the membrane performances were investigated. Surface chemical compositions, surface and cross-section morphologies, degree of crystallinity and the thermal stability of the membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA) respectively. The mechanical properties of the membranes were also investigated. All the experimental results indicated that the properties of the composite membranes were improved due to the addition of NCC. The pure water flux of composite membranes can reach 230.8 L/(m2 h) and increase up to 47.5% compared with pure PVDF membranes. At the same time, the rejection ratio of a bovine serum albumin solution (1 g/L) was up to 92.5%. The porosity and the mean pore size of the composite membranes were 65% and 49 nm, respectively. Due to the addition of NCC, the degree of crystallinity was increased to 52.1% resulting in the enhanced mechanical properties. A typical asymmetric structure, which was composed of sponge-like dense layer and finger-like microporous support layer, was observed in SEM images of composite membranes.

关键词： Poly(vinylidene fluoride) (PVDF) Nano-crystalline cellulose (NCC) Composite membranes Improved performances

Simultaneous variable selection for heteroscedastic regression models

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science china Mathematics 2011年第3期54卷 515-530页

作者： ZHANG ZhongZhan1 & WANG DaRong2 1college of Applied sciences, beijing university of technology, beijing 100124, china 2The Pilot college, beijing university of technology, beijing 101101, china college of Applied sciences Beijing University of Technology Beijing China The Pilot college Beijing University of Technology Beijing China

In this paper, we propose a new criterion, named PICa, to simultaneously select explanatory variables in the mean model and variance model in heteroscedastic linear models based on the model structure. We show that the new criterion can select the true mean model and a correct variance model with probability tending to 1 under mild conditions. Simulation studies and a real example are presented to evaluate the new criterion, and it turns out that the proposed approach performs well.

关键词： variable selection heteroscedastic regression models adjusted profile log-likelihood AIC BIC

Synthesis and magnetic properties of CdS/α-Fe_2O_3 hierarchical nanostructures

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 997-1002页

作者： CHEN YuJin1,2,3, SHI XiaoLing1, CAO MaoSheng1 & ZHU ChunLing4 1 School of Materials science and Engineering, beijing Institute of technology, beijing 100081, china 2 Micro-Nano Technologies Research Center, Hunan university, Changsha 410082, china 3 college of science, Harbin Engineering university, Harbin 150001, china 4 college of Material science and Chemical Engineering, Harbin Engineering university, Harbin 150001, china School of Materials science and Engineering Beijing Institute of Technology Beijing China Micro-Nano Technologies Research Center Hunan University Changsha China college of science Harbin Engineering University Harbin China college of Material science and Chemical Engineering Harbin Engineering University Harbin China

CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 K). Importantly, the hierarchical nanostructures exhibit weakly ferromagnetic characteristics at 300 K. A sharp peak assigned to the surface trap induced emission are observed in room temperature PL spectra. Combining with the optoelectronic properties of CdS, the CdS/ α-Fe2O3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2O3 CdS hierarchical nanostructures magnetic properties

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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science china(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2 1 college of Computer science and technology, beijing university of technology, beijing 100124, china 2 State Key Laboratory of Information Security, Graduate university of Chinese Academy of sciences, beijing 100049, china college of Computer science and technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing

The Theoretical Basis of Modern High Agrobiolgical science and technology

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农业生物技术学报 2004年第2期12卷 119-120页

作者： WU Zhong-Xian(alias J.S.) Ph. D Professor (college of animal science and technology, china agricultural university, beijing 100094, china) college of animal science and technology China Agricultural University 北京 100094

Philosophy of zero: Zero and its Interactions; O-rigin of 0 and 1. Consciousness: Classification of Consciousness: Consciousness of Stones, Conscious ness of Amoeba, Consciousness of Man, Conscious ness of Angels, Consciousness of God (Monadism of Leibniz). Relations between Man and Consciousness: Logical, birth of Logic, i.e. Deduction, discovered in Greece and perfected by Aristotle. Quantitative, birth of numbers, discovered by Arabians. Discovery of 0, the greatest World Mathematician, supposed to be the Hindus, mentioned by Bramagupta. Birth of Interac tions: Example: Interaction of 0 and 0: 0 + 0, 0 - 0, 0x0,0-^0, the last term indefinite, birth of something new. Discoverer of the Calculus is Newton. Besides, he discovered Universal Gravitation. Interaction of and 2: 1 Absolute; 2 Relative. Relativeness + Universal Gravitation = birth of Einstein's Relativity. Which is greater, Einstein or Newton? Answer: Einstein is greater since he discovered both Relativity and Quantum Theory which changed our entire view of the universe.

关键词： The Theoretical Basis of Modern High Agrobiolgical science and technology 遗传学报

Surface Nanocrystallization of Magnesium Alloy AZ91D by High-Energy Shot Peening

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Journal of Wuhan university of technology(Materials science) 2009年第4期24卷 515-519页

作者：张津 School of Materials science & Engineering University of Science and Technology Beijing college of Materials science & Engineering Chongqing University of Technology

High-energy shot peening （HESP）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XRD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100℃ for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESP microhardnss corrosion resistance

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life science,Capital Normal university,beijing 100037,china 2 college of Applied sciences and Humanities,beijing Union university,beijing 100083,china college of Life science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure