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991.
本文提出一种用高密度位相型闪耀光栅测取板的曲率和斜率的单光束错位云纹干涉法,由于这一方法具有高灵敏度。大量程和高反差的优点。可有效地用来求解板的弯曲问题。文中还给出了周边固定圆板和带缺口的方板两个应用实例。 相似文献
992.
采用耦合水平集--体积分数法(CLSVOF)对液滴撞击倾斜表面液膜后液膜的形态演化及飞溅过程进行数值模拟, 并对液滴撞击液膜过程中形成的空气卷吸现象进行研究并探讨了撞击角对此的影响, 分析了液滴撞击后液体内部的压力和速度分布, 对液滴撞击倾斜表面液膜的飞溅过程进行讨论, 并与实验结果进行了对比, 验证了CLSVOF方法研究液滴撞击倾斜液膜的可行性. 结果表明, 液滴撞击倾斜液膜时前后两部分飞溅现象产生的机理不同, 前半部分飞溅是由于压差引起的颈部射流, 而后半部分则是由液膜径向流动产生的飞溅现象. 随着撞击角的增大, 空气卷吸气泡数量减少. 相似文献
993.
Liposomes have been extensively investigated as possible carriers for diagnostic or therapeutic agents due to their unique properties. However, liposomes still have not attained their full potential as drug and gene delivery vehicles because of their insufficient morphological stability. Recently, a super-stable and freestanding hybrid liposomal cerasome (partially ceramic- or silica-coated liposome) has drawn much attention as a novel drug delivery system because its atomic layer of polyorganosiloxane surface imparts higher morphological stability than conventional liposomes and its liposomal bilayer structure reduces the overall rigidity and density greatly compared to silica nanoparticles. Cerasomes are more biocompatible than silica nanoparticles due to the incorporation of the liposomal architecture into cerasomes. Cerasomes combine the advantages of both liposomes and silica nanoparticles but overcome their disadvantages so cerasomes are ideal drug delivery systems. The present review will first highlights some of the key advances of the past decade in the technology of cerasome production and then review current biomedical applications of cerasomes, with a view to stimulating further research in this area of study. 相似文献
994.
S. -L. Dai Z. -P. Cheng R. -K. Huang Q. -Y. Guan Y. -J. Liang W. -Q. Huang J. -R. Zhou C. -L. Ni 《Journal of Structural Chemistry》2014,55(2):374-378
A new hybrid material [BiF4BrBzTPP]2[Co(NCS)4] (1) (BiF4BrBzTPP+ = 2,6-bisfluoro-4-bromobenzyl-triphenylphosphinium, NCS? = isothiocyanate) is synthesized and characterized by elemental analyses, IR, UV spectra, ESI-MS, molar conductivity, single crystal X-ray diffraction and magnetic susceptibility measurements. Compound 1 crystallizes in the monoclinic space group C2/c with a = 15.272(2) Å, b = 24.779(3) Å, c = 14.482(2) Å, β = 101.037(2)°, V = 5378.9(12) Å3, Z = 4. The compound comprises two cations and one anion which exhibits a distorted tetrahedral coordination geometry. The short F...F, C...Br, and N...Br interactions and C-H...S hydrogen bonds consolidate the stacking of the molecules. Magnetic susceptibility measurements in the temperature range 2–300 K show that 1 exhibits weak antiferromagnetic coupling behavior. 相似文献
995.
Dr. Man‐Sheng Chen Xiong‐Wen Tan Dr. Chun‐Hua Zhang Dai‐Zhi Kuang 《无机化学与普通化学杂志》2011,637(9):1220-1223
A new three‐dimensional (3D) porous framework [Zn(INAIP)] · DMA · H2O ( 1 ) [INAIP = 5‐(isonicotinamido)isophthalate, DMA = N,N′‐dimethylacetamide] was synthesized by solvothermal methods and characterized by single‐crystal and powder X‐ray diffraction, as well as thermogravimetric analysis. The results of X‐ray diffraction analyses revealed that complex 1 has an unusual 3D architecture with the (3,6)‐connected rutile ( rtl ) topology. The adsorption behavior shows that compound 1 exhibits selective adsorptions of CO2 over N2 after the removal of the solvent molecules within the pores. 相似文献
996.
A facile and high-throughput strategy is presented to fabricate three-dimensional (3D) hierarchically porous Ag films, with clean surfaces, via plasma etching Ag-coated electrospun nanofiber template. The films are built of Ag porous nanotubes and are homogeneous in macro-size but rough and porous in nanoscale. Each nanotube-block is micro/nanostructured with evenly distributed nanopores on the tube walls. The film architecture (or the shape, arrangement, and distribution density of porous nanotubes; the number and size of nanopores) can be easily controlled by the nanofiber-template configuration, Ag coating, and plasma etching conditions. Such hierarchically porous films could be very useful, such as in catalysis, sensors, and nanodevices. They have exhibited significantly structurally enhanced surface-enhanced Raman scattering performance with good stability and reproduction, and shown the possibility of molecule-level detection. Also, the strategy is universal for fabricating other hierarchically structured 3D metal porous films, such as porous Ag hollow sphere arrays. 相似文献
997.
998.
Two new guaiane-type sesquiterpenoid glucosides (1 and 2) were isolated from the fruit of Gardenia jasminoides Ellis. Their structures were elucidated to be (1R,7R,10S)-11-O-β-D-glucopyranosyl-4-guaien-3-one (1) and (1R,7R,10S)-7-hydroxy-11-O-β-D-glucopyranosyl-4-guaien-3-one (2) by one- and two-dimensional NMR techniques ((1)H NMR, (13)C NMR, HSQC, HMBC and NOESY), MS, CD spectrometry and chemical methods. 相似文献
999.
This short communication describes the interaction between toll-like receptor 4 (TLR4) and lipopolysaccharide (LPS, its specific ligand) using analytical methods. Their interaction has been evidenced in many reports. Nevertheless, there are few reports focused on their binding constant. In this research, the interaction between TLR4 and LPS is investigated using mobility shift method by CZE. To optimize the electrophoresis conditions, the effecting factors, running buffer, sample concentration, injection duration, and operation voltage of electrophoretic on the mobility shift are studied in detail. Electrophoresis conditions were described as follows: borate buffer (pH 7.4, 20 mM), 5 s for 50 mbar pressure injection duration, and 13 kV of separation voltage in 41.5 cm fused silica capillary with 75 μm id and 375?μm od. The combination constant of TLR4 and LPS is calculated using Scatchard methods. The Scatchard liner correlation is y=-0.0165x+0.1456, binding constant is K=1.65 x 10? (g/mL)?1. 相似文献
1000.
Ben-Mei Wei Zhi-Yong Zhang Zhi-Qun Dai Kai-Cheng Zhang 《Monatshefte für Chemie / Chemical Monthly》2011,57(1):1029-1033