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可变晶格常数乙醇-二氧化硅胶质光子晶体中的Raman散射

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物理学报 2004年第9期53卷 3059-3064页

作者：刘晓东倪培根程丙英张道中中国科学院物理研究所光物理实验室

制备了乙醇二氧化硅三维胶质光子晶体 ,其晶格常数随着晶体高度的变化而变化 .用皮秒脉冲激光在不同高度激发光子晶体中乙醇产生Raman信号 ,得到了两个结果 :1 )即使Raman信号的中心频率与光子晶体的带隙中心频率一致 ,在其禁带方向... 详细信息

制备了乙醇二氧化硅三维胶质光子晶体 ,其晶格常数随着晶体高度的变化而变化 .用皮秒脉冲激光在不同高度激发光子晶体中乙醇产生Raman信号 ,得到了两个结果 :1 )即使Raman信号的中心频率与光子晶体的带隙中心频率一致 ,在其禁带方向上测得的强度也没有被抑制到与带隙深度同样的量级 ;2.)尽管单纯的具有Raman信号频率的入射光的透过率随着高度的变化而剧烈变化 ,但在光子晶体中产生的Raman信号强度却几乎不随高度的变化而变化 ,即光子晶体的赝带隙几乎没有影响在禁带方向上测得的Raman信号强度 .基于“光子晶体带隙对入射光和内部光源传播影响不同”的物理机理 ,比较合理地解释了这两个实验结果。

关键词：光子晶体 Raman散射赝带隙内部光源晶格常数乙醇-二氧化硅胶质晶体

Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2.Tong-Jie Zhang1,3 and Bao-Quan Wang4 1 Department of Astronomy,beijing Normal University,beijing 100875,{2. 2.Business Office,beijing Planetarium,beijing 100044,{2. 3 center for High Energy Physics,Peking University,beijing 100871,{2. 4 Department of Physics,Dezhou University,Dezhou 2.302.,{2. Department of Astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China center for High Energy Physics Peking University Beijing 100871 China Department of Physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2.minimization method,we get α = 0.81＋0.19-0.2. and ΩM = 0.32.0.12.0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.2. ± 0.1,we get α = 0.93＋0.07-0.19 and ΩM = 0.31＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

Effect of Continuous Vegetable Cultivation on Phosphorus Levels of Fluvo-Aquic Soils

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Pedosphere 2004年第2期14卷 171-176页

作者： WANGXin-Min HOUYan-Lin DepartmentofSoilEnvironmentalScience ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085（China）.E-mail：kirk123@***

Soil P status, inorganic P fractions, and P sorption properties were studiedusing sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetableproduction in comparison with a soil used for grain crop production in Zhengzhou, Henan Province,china P fractions, Olsen-P, and OM were determined at different depths in the soil profile andsorption isotherm experiments were performed Most P in excess of plant requirements accumulated inthe topsoil and decreased with soildepth. Total P, inorganic P, and OM concentrations increased withcontinued horticultural use Olsen-P concentrations in the 0-2. cm depth of horticultural soils were9 to 2. times higher than those of the grain crop soil. A linear transformation of the Langmuirequation showed that the P adsorption maximum (491.3 mg P kg^(-1)) and the maximum phosphatebuffering capacity (162.1 L kg^(-1)) for 80--100 cm were greater in the grain crop soil than thehorticultural soils. Thus, the most immediate concern with excess P were in areas where heavy Pfertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandysoils and high organic matter content.

关键词： fractions horticultural soils phosphorus status sorption

Fabrication and Characterization of GCO Electrolyte Films

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稀有金属材料与工程 2006年第S3期 530-532页

作者： Yuxing Xu~1 Zilong Tang~1 Zhongtai Zhang~1 Zhigang Zhou~1 Lihai Xu~2.(1.State Key Laboratory of New Ceramic and Fine Processing,Department of Materials Science and Engineering,Tsinghua University,beijing 100084,china) (2.{2. of condensed matter Physics and Material Physics,School of Science,Beihang University,beijing 100083,china)

Gd-doped Ceria (GCO:Gd0.1Ce0.9O1.95) sensing films have been fabricated successfully on glasses and porous Al2.3ceramic substrates by RF magnetron *** conditions such as power and temperature have been investigated and the sample was characterized in detail by XRD,SEM and AC impedance *** results show that the films grow preferentially along the （111） compact plane with a pure fluorite structure and the crystal grain grows more sufficiently with increasing of the annealing *** addition,a high oxygen ion conductivity of 2.2.×***-1is achieved at 800℃.

关键词： electrolyte film GCO RF magnetron sputtering oxygen conductivity

Inhibiting pain with pain——A basic neuromechanism of acupuncture analgesia

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chinese Science Bulletin 2001年第17期46卷 1485-1494页

作者： LIU Xianginstitute of Acupuncture and Moxibustion, china {2. of Traditional chinese Medicine, beijing 100700, china institute of Acupuncture and Moxibustion China Academy of Traditional Chinese Medicine Beijing China

(i) The structure and function of the meridian (channel and collateral) described by ancient medical doctors may correspond to the blood circulation, nerve control and neurohumoral modulation of modern medicine. (ii) The needling, which can injure the tissue, is a noxious stimulation inducing pain. Acupuncture manipulation, such as lifting and thrusting, twisting and twirling, or electroacupuncture (EA) with the sufferable biggest intensity for patients should be a stronger pain stimulation. The needling sensation of soreness, numbness, distension and heaviness is a deep pain. (iii) There is an intrinsic analgesic system in brain, which centers around the periventricular and periaqueductal grey matter, contains endorphins as possible mediators, goes through the descending inhibition system in medulla oblon-gata, and acts on the gating mechanism in spinal cord. Itcould be producing analgesia while the system is activated. (iv) NRM might be a supraspinal center modulating pain, and the R-S neurons could

关键词： acupuncture analgesia Inhibiting pain with pain negative feedback mechanism of pain nucleus raphe magnus afferent C fiber capsaicm.

Dember effect induced photovoltage in Oxide p-n junctions

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Dember effect induced photovoltage in Oxide p-n junctions

A comparative study of magnetic properties between whole cells and isolated magnetosomes of Magnetospirillum magneticum AMB-1

第七届全国光学前沿问题讨论会

作者： Jin Kui-juan~1 Zhao Kun~2.Lu Hui-bin~1 Liao Leng~1 Yang Guo-zhen~1 (1 beijing National Laboratory for condensed {2. Physics,institute of Physics,chinese academy of sciences,beijing 100080,china 2.Department of Mathematics and Physics,china University of Petroleum,beijing 102.49,china)

An unusual and rather large transient lat- eral photovoltage(LPV)is observed in LaSr MnO/SrNbTiO and LaSrOMnO/Si hetero- junctions under the nonuniform irradiation of pulsed laser. The irreversible LPVs on both sides ...

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A comparative study of magnetic properties between whole cel...

Anion coordination complex [ClPt(bpt)_4]Cl (bpt= N,N'-bis(3-pyridylmethyl)-2.thiourea)

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： LI JinHua~(1,2,3),PAN YongXin~(1,3*),LIU QingSong~(3,4),QIN HuaFeng~4,DENG ChengLong~4, CHE RenChao~5 & YANG XinAn~5 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Franco-chinese Biomineralization and Nano-structures Laboratory,beijing 100029,china 4 State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china 5 beijing National Laboratory for condensed matter Physics,institute of Physics,chinese academy of sciences,beijing 100080,china

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment,as well as novel nano-biomaterials in biotechnological and biomedical *** carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated *** revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arranged in the form of linear fragmental *** distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic *** the whole cells,the strong intra-chain interactions and weak inter-chain interactions generate behaviors of non-interacting uniaxial single-domain ***δ-ratio is 3.0 and passes the Moskowitz *** contrast,the isolated magnetosome sample has reduced values of coercivity andδ-ratio(1.5),due to increasing three-dimensional magnetostatic interactions and collapse of magnetosome *** observations provide useful insights into applications of the biogenic magnetite(magnetosomes)in magnetic nano-materials and magnetofossils in the paleomagnetic and environmental magnetism.

关键词： Magnetospirillum magneticum AMB-1 isolated magnetosomes hysteresis loop FORC Verwey transition Moskowitz test

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Science china Chemistry 2009年第4期52卷 471-474页

作者： LI Xin1,LI Hui2.YU ShuYan1,4 & LI YiZhi3 1 Laboratory for Self-Assembly Chemistry,Department of Chemistry,Renmin University of china,beijing 100872.{2. 2.School of Materials Science and Engineering,East china University of Science and Technology,Shanghai 2.02.7,{2. 3 State Key Laboratory of Coordination Chemistry,Coordination Chemistry institute,Nanjing University,Nanjing 2.0093,{2. 4 State Key Laboratory of Structural Chemistry,Fujian institute of Research on the Structure of matter,chinese academy of sciences,Fuzhou 350002.{2. 1. Laboratory for Self-Assembly Chemistry Department of Chemistry Renmin University of China Beijing 100872 China 2. School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China 4. State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China 3. State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing 210093 China

The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2.thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 anion receptor adopts a cone conformation to bind the chloride anion through hydrogen bonds and electrostatic interaction in which the four branches of the thiourea ligands bind the chloride anion to form N-H…Cl-hydrogen bonds (3.49-3.81). The entraped chloride anion is situated above the Pt(Ⅱ) center at 3.52.. Further second-sphere coordination assemby from the Pt(bpt)4 core with 8 zinc(Ⅱ) tetraphenylporphyrins (ZnPr) is discussed.

关键词： anion coordination platinum(Ⅱ) complex supramolecular chemistry hydrogen bonds second-sphere coordination

Effect of Inhomogeneity of Particles on Band-Gap of Silica Colloidal Crystals Fabricated by Vertical Deposition Method

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Effect of Inhomogeneity of Particles on Band-Gap of Silica C...