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排序方式: 共有4478条查询结果,搜索用时 31 毫秒
981.
982.
Amenomori M Cao Z Ding LK Feng ZY Hibino K Hotta N Huang Q Huo AX Jia HY Jiang GZ Jiao SQ Kajino F Kasahara K Labaciren Mei DM Meng L Meng XR Mimaciren Mizutani K Mu J Nanjo H Nishizawa M Nusang Oguro A Ohnishi M Ohta I Ren JR Saito T Sakata M Shi ZZ Shibata M Shirai T Sugimoto H Sun XX Tai A Taira K Tan YH Tateyama N Torii S Wang H Wen CZ Yamamoto Y Yao XY Yu GC Yuan P Yuda T Zeng JG Zhang CS Zhang HM Zhang L Zhasang Zhaxiciren Zhou WD 《Physical review D: Particles and fields》1993,47(7):2675-2681
983.
M. C. Martínez-Tomás V. Muñoz M. V. Andrés A. Segura A. Chevy 《Zeitschrift für Physik B Condensed Matter》1993,91(1):25-30
High resolution and time resolved photoluminescence in low resistivity Cd dopedp-type InSe in the 32K–155K temperature range are reported. The photoluminescence spectra consist of a broad band that turns out to have three components with different lifetimes (less than 0.1 s, 2.1±0.1 s and 17±1 s). For a given sample, the relative contribution of the components depends on the excitation conditions. The two components with longer lifetime have an asymmetric gaussian shape and a temperature dependence of both the intensity and the decay time which suggest that they are emitted by complex centers, in which the ground state originates from the Cd related acceptor. The fast component and the weak structures in the high energy tail of the broad band, with much shorter lifetime, are proposed to be due to distant donor-acceptor pair recombination. 相似文献
984.
Rodríguez Amalia Muñoz Ernestina Sánchez Francisco Moya María Luisa Burgess John 《Transition Metal Chemistry》1992,17(1):5-8
Transition Metal Chemistry - The wavelengths of absorption maxima are reported for two ligand field bands of hexathiocyanatochromate(III), $ {? Cr(NCS)_{6}^{3-}} $, over a range of... 相似文献
985.
986.
M. J. Arias P. Muñoz J. R. Moyano J. M. Ginés Cs. Novák 《Journal of Thermal Analysis and Calorimetry》1998,51(3):973-980
Techniques of DSC, TG/DTG, EGD and HSM were used to study and characterize the complex formation and state of dispersion after co-grinding of a 1:1 mixture of omeprazole (OME) and γ-cyclodextrin (γ-CD) under various conditions. The changed crystalline properties of the composites obtained by co-grinding suggested distinct types of interactions between the components, as a consequence of the variations in the grinding procedure. The experimental data clearly revealed that a true solid complex OME-γ-CD was obtained only by wetting the mixture of the components with phosphate buffer during the co-grinding. Other co-grinding procedures yielded only amorphous drug—CD mixtures or their combination with partial complexation. 相似文献
987.
Popovici M Gich M Roig A Casas L Molins E Savii C Becherescu D Sort J Suriñach S Muñoz JS Baró MD Nogués J 《Langmuir : the ACS journal of surfaces and colloids》2004,20(4):1425-1429
Monoliths of iron oxide-silica aerogel nanocomposites have been synthesized using a novel synthesis route which consists of impregnating silica wet gels with anhydrous iron(II) precursors followed by ethanol supercritical drying of the gels. The process yields aerogels exhibiting high porosity, large surface areas (approximately 900 m2/g), rather low densities (approximately 0.6 g/cm3), and a homogeneous distribution of single-phase maghemite, gamma-Fe2O3, nanoparticles with average sizes in the 7-8 nm range. Remarkably, the gamma-Fe2O3 nanoparticles are obtained in the as-dried state without the need of postannealing. The nanoparticles are mostly superparamagnetic at room temperature but become blocked in a ferrimagnetic state at lower temperatures. 相似文献
988.
Preparation of MMA-BA-DMAEMA Nanosized Latex 总被引:1,自引:0,他引:1
YuYangLIU MuJieYANG 《中国化学快报》2003,14(8):863-865
The terpolymer latex of methyl methacrylate (MMA)/butyl acrylate (BA)/ dimethyl aminoethyl methacrylate (DMAEMA) with diameter of less than 100 nm was prepared by seeding semi-continuous emulsion copolymerization using APS (ammonium pcrsulfate) / TMEDA (N,N,N,N-tetramethylethylenediamine) as the redox initiators and SDS (sodium dodecylsulfate) and OP (P-octylpolyethylene glycol phenylether) as co-emulsifiers. The factors that influenced the process stability of the copolymerization and the particle size of the latex were investigated. The addition of aqueous ammonia as coagulation inhibitor provided better process stability of the copoly- merization. The addition of acetic acid as the acidification agent caused a remarkable reduction of the latex particle size. 相似文献
989.
Blay G Fernández I Giménez T Pedro JR Ruiz R Pardo E Lloret F Muñoz MC 《Chemical communications (Cambridge, England)》2001,(20):2102-2103
A new manganese(II) oxamato dimer possesing an unprecedented Mn2(mu-O2CR)(mu-OH2...O2CR) core has been synthesised, structurally and magnetically characterised, and used as a catalyst for the oxidation of alkanes to alcohols and ketones by ButO2H and O2 in CH2Cl2 at rt. 相似文献
990.
Dieckmann GR Dalton AB Johnson PA Razal J Chen J Giordano GM Muñoz E Musselman IH Baughman RH Draper RK 《Journal of the American Chemical Society》2003,125(7):1770-1777
Carbon nanotubes have properties potentially useful in diverse electrical and mechanical nanoscale devices and for making strong, light materials. However, carbon nanotubes are difficult to solubilize and organize into architectures necessary for many applications. In the present paper, we describe an amphiphilic alpha-helical peptide specifically designed not only to coat and solubilize carbon nanotubes, but also to control the assembly of the peptide-coated nanotubes into macromolecular structures through peptide-peptide interactions between adjacent peptide-wrapped nanotubes. The data presented herein show that the peptide folds into an amphiphilic alpha-helix in the presence of carbon nanotubes and disperses them in aqueous solution by noncovalent interactions with the nanotube surface. Electron microscopy and polarized Raman studies reveal that the peptide-coated nanotubes assemble into fibers with the nanotubes aligned along the fiber axis. Most importantly, the size and morphology of the fibers can be controlled by manipulating solution conditions that affect peptide-peptide interactions. 相似文献