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chinese Journal of Polymer Science 2000年第1期18卷 19-23页

作者： Xin-tao Shuai Zbigniew Jedlinski Qiang Luo Nozirow Farhod institute of chemistry, chinese academy of sciences, beijing 100080, china institute of Polymer chemistry, Polish academy of sciences, 41-800 Zabrze, Poland institute of Synthetic Fibre, chinese academy of Textile sciences, beijing 100025, china chinese Acad Sci Inst Chem Beijing 100080 Peoples R China Polish Acad Sci Inst Polymer Chem PL-41800 Zabrze Poland chinese Acad Text Sci Inst Synthet Fibre Beijing 100025 Peoples R China

A novel kind of copolymer with ABA-type block structure was synthesized by anionic ring-opening polymerization of beta-butyrolactone (beta-BL) in the presence of a PEG-based dicarboxylates as macroinitiators which were prepared by the esterification of aliphatic cyclic anhydride and poly(ethylene glycol) (PEG) oligomers (M-n = 2000, 4000 and 6000) and conversion of potassium dicarboxylates. The resultant copolymers as well as the intermediates were characterized by IR, H-1-NMR and GPC.

关键词： block copolymer poly(ethylene glycol) poly(3-hydroxybutyric acid)

Enthalpy and entropy interaction parameters of sodium chloride with some monosaccharides in water

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Science china chemistry 2004年第1期47卷 59-66页

作者： ZHUO Kelei, WANG Jianji, BAI Guangyue, YAN Haike & WANG HangingSchool of chemistry and Environmental Science, Henan Normal University, Xinxiang 453002, china institute of chemistry, chinese academy of sciences, beijing 100080, china Lanzhou institute of Chemical Physics, chinese academy of sciences, Lanzhou 730000, china 1. School of chemistry and Environmental Science Henan Normal University 453002 Xinxiang China 2. institute of chemistry Chinese Academy of Sciences 100080 Beijing China 3. Lanzhou institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction parameter - entropy interaction parameter - calorimetry

关键词： sodium chloride, monosaccharide, enthalpy interaction parameter, entropy interaction parameter, calorimetry.

REACTIONS OF PYRITE IN CATALYTICAL OXIDATION ACID LEACHING SYSTEM

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中国有色金属学会会刊：英文版 1995年第2期5卷 43-48页

作者： Xia, Guangxiang Tu, Taozhi Yang, Hanlin shi, Wei(institute of Chemical Metallurgy, chinese academy of sciences, beijing 100080) chinese Acad of sciences Beijing China

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关键词： catalytic oxidation acidic leaching pyrite oxidation pretreatment

Spectroscopic evidence for triplet excitation energy transfer among carotenoids in the LH2 complex from photosynthetic bacterium Rhodopseudomonas palustris

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Science china chemistry 2004年第1期47卷 80-90页

作者： FENG Juan, WANG Qian, ZHANG Xujia, HUANG Youguo, Al Xicheng, ZHANG Xingkang & ZHANG JianpingState Key Laboratory for Structural chemistry of Unstable and Stable Species, institute of chemistry, chinese academy of sciences, beijing 100080, china National Laboratory of Biomacromolecules, institute of Biophysics, chinese academy of sciences, beijing 100101, china 1. State Key Laboratory for Structural chemistry of Unstable and Stable Species institute of chemistry Chinese Academy of Sciences 100080 Beijing China 2. National Laboratory of Biomacromolecules institute of Biophysics Chinese Academy of Sciences 100101 Beijing China

The LH2 complex from Rhodopsudomonas (Rps.) palustris is unique in the heterogeneous carotenoid compositions. The dynamics of triplet excited state Carotenoids (3Car* has been investigated by means of sub-microsecond time-resolved absorption spectroscopy both at physiological temperature (295 K) and at cryogenic temperature (77K). Broad and asymmetric T n ←T 1 transient absorption was observed at room temperature following the photo-excitation of Car at 532 nm, which suggests the contribution from various carotenoid compositions having different numbers of conjugated C=C double bonds (Nc=c). The triplet absorption bands of different carotenoids, which superimposed at room temperature, could be clearly distinguished upon decreasing the temperature down to 77 K. At room temperature the shorter-wavelength side of the main Tn04T1 absorption band decayed rapidly to reach a spectral equilibration with a characteristic time constant of ∽1 μs, the same spectral dynamics, however, was not observed at 77 K. The aforementioned spectral dynamics can be explained in terms of the triplet-excitation transfer among heterogeneous carotenoid compositions. Global spectral analysis was applied to the time-resolved spectra at room temperature, which revealed two spectral components peaked at 545 and 565 nm, and assignable to the Tn04 T1 absorption of Cars with Nc=c=11 and Nc=c=13, respectively. Surprisingly, the decay time constant of a shorter-conjugated Car, i.e. 0.72 ?s (aerobic) and 1.36 ?s (anaerobic), is smaller than that of a longer-conjugated Car, i.e. 2.12 us (aerobic) and 3.75 ?s (anaerobic), which is contradictory to the general rule of carotenoids and relative polyenes. The results are explained in terms of triplet-excitation transfer among different types of Cars. It is postulated that two Cars with different conjugation lengths coexist in an α, β-subunit in the LH2 complex.

关键词： purple photosynthetic bacteria, carotenoid, excited-state, time-resolved spectroscopy.

XPS Study on Water-Soluble Polymer Surfactant Film

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chinese Chemical Letters 1997年第12期8卷 0-0页

作者： Jian XU Liang He shi Mei Ling YE (Polymer Physics Laboratory, institute of chemistry, chinese academy of sciences, beijing 100080) chinese Acad Sci Inst Chem Polymer Phys Lab Beijing 100080 Peoples R China

By means of changing the detection angle, the molecular conformation of a new type of polymer surfactant, acrylamide-poly(oxyethykene alkyl ether)acrylate-anionic monomer random copolymer, was studied by x-ray photoel... 详细信息

关键词： XPS Study on Water-Soluble Polymer Surfactant Film

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Fiducial inference in the pivotal family of distributions

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Science china Mathematics 2006年第3期49卷 410-432页

作者： XU Xingzhong & LI Guoying Department of Mathematics, beijing institute of Technology, beijing 100081, china academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china 1. Department of Mathematics Beijing Institute of Technology Beijing 100081 China 2. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper a family, called the pivotal family, of distributions is considered.A pivotal family is determined by a generalized pivotal model. Analytical results show that a great many parametric families of distributions are pivotal. In a pivotal family of distributions a general method of deriving fiducial distributions of parameters is proposed. In the method a fiducial model plays an important role. A fiducial model is a function of a random variable with a known distribution, called the pivotal random element, when the observation of a statistic is *** method of this paper includes some other methods of deriving fiducial distributions. Specially the first fiducial distribution given by Fisher can be derived by the method. For the monotone likelihood ratio family of distributions, which is a pivotal family, the fiducial distributions have a frequentist property in the Neyman-Pearson view. Fiducial distributions of regular parametric functions also have the above frequentist property. Some advantages of the fiducial inference are exhibited in four applications of the fiducial distribution. Many examples are given, in which the fiducial distributions cannot be derived by the existing methods.

关键词： confidence bounds, fiducial distributions, fiducial model, frequentist prop-erty, generalized pivotal model, pivotal family of distributions, testing hypotheses.

Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3 & JIN Zhi1,2,1 institute of Computing Technology,chinese academy of sciences,beijing 100080,china 2 academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100080,china 3 Graduate University of chinese academy of sciences,beijing 100080,china institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Functional dissection of parabrachial substrates in processing nociceptive information

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Zoological Research 2024年第3期45卷 633-647页

作者： Jin Ke Wei-Cheng Lu Hai-Yang jing Shen Qian Sun-Wook Moon Guang-Fu Cui Wei-Xin Qian xiao-jing Che Qian Zhang shi-shi Lai Ling Zhang Ying-Jie Zhu jing-Dun Xie Tian-Wen Huang Shenzhen Key Laboratory of Drug Addiction Shenzhen-Hong Kong Institute of Brain ScienceBrain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China CAS Key Laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China University of chinese academy of sciences Beijing 100049China Department of Anesthesiology State Key Laboratory of Oncology in South ChinaGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhouGuangdong 510060China University of Science and Technology of china HefeiAnhui 230027China Department of Anesthesiology Shenzhen University General Hospital and Shenzhen University Academy of Clinical Medical SciencesShenzhen UniversityShenzhenGuangdong 518055China School of Medicine Yunnan UniversityKunmingYunnan 650091China

Painful stimuli elicit first-line reflexive defensive reactions and,in many cases,also evoke second-line recuperative behaviors,the latter of which reflects the sensing of tissue damage and the alleviation of *** lateral parabrachial nucleus(lPBN),composed of external-(elPBN),dorsal-(dlPBN),and central/superior-subnuclei(jointly referred to as slPBN),receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity ***,the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain *** this study,we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor(NK1R)(lPBNNK1R)are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle,while elPBN neurons are dispensable for driving such ***,lPBNNK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external ***,both lPBNNK1R and elPBN neurons contribute to chemical irritant-induced nocifensive *** results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.

关键词： Lateral parabrachial nucleus Substance P receptor Pain affect Defensive reaction Somatosensory

ORTHOGONAL PIECE-WISE POLYNOMIALS BASIS ON AN ARBITRARY TRIANGULAR DOMAIN AND ITS APPLICATIONS

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Journal of Computational Mathematics 2001年第1期19卷 55-66页

作者： Jia-chang Sun. (Parallel Computing Division, institute of Software, chinese academy of sciences, beijing 100080, china) 中科院软件所北京 00080

Presents a way to construct orthogonal piece-wise polynomials on an arbitrary triangular domain via barycentric coordinates. Solution of a boundary value problem for Laplace equation; Methodology; Results and discussion.

关键词： orthogonal piece-wise polynomials triangular domain eigen-decomposition

NUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESHNUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESH

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Journal of Computational Mathematics 2000年第5期18卷 521-540页

作者： Lan-chieh Huang (institute of Computational Mathematics and Scientific/Engineering Computing, chinese academy of sciences, beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

In this paper, the Crank-Nicholson + component-consistent pressure correction method for the numerical solution of the unsteady incompressible Navier-Stokes equation of [1] on the rectangular half-Staggered mesh has been extended to the curvilinear half-Staggered mesh. The discrete projection, both for the projection step in the solution procedure and for the related differential-algebraic equations, has been carefully studied and verified. It is proved that the proposed method is also unconditionally (in t) nonlinearly stable on the curvilinear mesh, provided the mesh is not too skewed. It is seen that for problems with an outflow boundary, the half-Staggered mesh is especially advantageous. Results of preliminary numerical experiments support these claims.

关键词： Unsteady incompressible Navier-Stokes equations Curvilinear half- staggered mesh Discrete projection.