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排序方式: 共有151条查询结果,搜索用时 31 毫秒
81.
Katsuaki Baba Mamoru Tobisu Naoto Chatani 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(45):11883-11883
82.
Miguel Gelabert‐Besada Manuel Garcia‐Magariños Carla Santos Manuel Fondevila Ángel Carracedo Maria Victoria Lareu 《Electrophoresis》2013,34(8):1151-1162
There is growing interest in developing additional DNA typing techniques to provide better investigative leads in forensic analysis. These include inference of genetic ancestry and prediction of common physical characteristics of DNA donors. To date, forensic ancestry analysis has centered on population‐divergent SNPs but these binary loci cannot reliably detect DNA mixtures, common in forensic samples. Furthermore, STR genotypes, forming the principal DNA profiling system, are not routinely combined with forensic SNPs to strengthen frequency data available for ancestry inference. We report development of a 12‐STR multiplex composed of ancestry informative marker STRs (AIM‐STRs) selected from 434 tetranucleotide repeat loci. We adapted our online Bayesian classifier for AIM‐SNPs: Snipper, to handle multiallele STR data using frequency‐based training sets. We assessed the ability of the 12‐plex AIM‐STRs to differentiate CEPH Human Genome Diversity Panel populations, plus their informativeness combined with established forensic STRs and AIM‐SNPs. We found combining STRs and SNPs improves the success rate of ancestry assignments while providing a reliable mixture detection system lacking from SNP analysis alone. As the 12 STRs generally show a broad range of alleles in all populations, they provide highly informative supplementary STRs for extended relationship testing and identification of missing persons with incomplete reference pedigrees. Lastly, mixed marker approaches (combining STRs with binary loci) for simple ancestry inference tests beyond forensic analysis bring advantages and we discuss the genotyping options available. 相似文献
83.
84.
The rhodium-catalyzed reaction of 2-germylphenylboronic esters with alkynes in the presence of a rhodium(I) catalyst is established as a modular method for the synthesis of an array of benzogermole derivatives. The reaction proceeds through the activation of C(sp(3))-Ge bonds. The mechanism of this new bond activation process is discussed based on the activation aptitude of alkyl and aryl substituents on germanium. 相似文献
85.
Takanori Hirano Takeo Oku Masayuki Kawaguchi Katsuaki Suganuma 《Molecular Crystals and Liquid Crystals》2013,570(1):787-792
Abstract Boron nitride nanocapsules with gold, iron oxide and germanium nanoparticles were produced. High-resolution electron microscopy and electron energy-loss spectroscopy showed the gold, iron oxide and germanium nanoparticles were encapsulated in the boron nitide sheets. Weak peaks of photoluminescence spectrum were observed from the nanocapsules with germanium nanoparticles. The present work indicates that the boron nitide nanocapsules with conducting, magnetic and semiconductor nanoparticles can be produced by are melting method, and models for the formation mechanism and nano-structures of the boron nitide nanocapsule were proposed. 相似文献
86.
Junichiro Sameshima Aya Takenaka Yuichi Muraji Shingo Ogawa Masanobu Yoshikawa Katsuaki Suganuma 《Surface and interface analysis : SIA》2019,51(7):743-753
To examine precise depth profiles at the interface of SiO2/SiC, a high resolution that can detect slight discrepancies in the distribution is needed. In this study, an experimental method to achieve a high resolution of less than 1 nm was developed by using dual-beam time-of-flight secondary ion mass spectrometry (TOF-SIMS). The analysis was preceded by the following three steps: (1) determination of the optimal analytical conditions of the analysis beam (Bi+) and sputtering beam (Cs+), (2) verification of the etching methods to thin the SiO2 layer, and (3) confirmation of the benefits of the low-energy sputtering beam directed toward SiO2/SiC samples. By using the secondary ion intensity peak-to-valley ratio of BN− and BO− of a sample with delta-doped boron multilayers, the appropriate Bi+/Cs+ condition for a high depth resolution was determined for each energy level of the sputtering beam. Upon verification of the etching methods to thin the SiO2 layer, slight discrepancies were found between samples that were obtained with different etching methods. The difference in the roughness values of the etched surfaces was proactively utilized for the performance confirmation of the low-energy sputtering beam by means of precise observation of the profiles at the SiO2/SiC interface. The use of a Cs beam with a low energy between 0.25 and 0.5 keV enabled the detection of slight discrepancies in the roughness of less than 1 nm between samples. The aforementioned method has the potential to accurately detect discrepancies in the intrinsic distribution at the SiO2/SiC interface among samples. 相似文献
87.
88.
Imura T Ohta N Inoue K Yagi N Negishi H Yanagishita H Kitamoto D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(9):2434-2440
Self-assembling properties of "natural" glycolipid biosurfactants, mannosyl-erythritol lipids A and B (MEL-A, MEL-B), which are abundantly produced from yeast strains, were investigated by using the fluorescence-probe method, dynamic light-scattering (DLS) analysis, freeze-fracture transmission electron microscopy (FF-TEM), and synchrotron small/wide-angle X-ray scattering (SAXS/WAXS) analysis, among other methods. Both MEL-A and MEL-B exhibit excellent self-assembly properties at extremely low concentrations; they self-assemble into large unilamellar vesicles (LUV) just above their critical-aggregation concentration (CAC). The CAC(I) value was found to be 4.0x10(-6) M for MEL-A and 6.0x10(-6) M for MEL-B. Moreover, the self-assembled structure of MEL-A above a CAC(II) value of 2.0x10(-5) M was found to drastically change into sponge structures (L3) composed of a network of randomly connected bilayers that are usually obtained from a complicated multicomponent "synthetic" surfactant system. Interestingly, the average water-channel diameter of the sponge structure was 100 nm. This is relatively large compared with those obtained from "synthetic" surfactant systems. In addition, MEL-B, which has a hydroxyl group at the C-4' position on mannose instead of an acetyl group, gives only one CAC; the self-assembled structure of MEL-B seems to gradually move from LUV to multilamellar vesicles (MLV) with lattice constants of 4.4 nm, depending on the concentration. Furthermore, the lyotropic-liquid-crystal-phase observation at high concentrations demonstrates the formation of an inverted hexagonal phase (H2) for MEL-A, together with a lamella phase (L(alpha)) for MEL-B, indicating a difference between MEL-A and MEL-B molecules in the spontaneous curvature of the assemblies. These results clearly show that the difference in spontaneous curvature caused by the single acetyl group on the head group probably decides the direction of self-assembly of glycolipid biosurfactants. The unique and complex molecular structures with several chiral centers that are molecularly engineered by microorganisms must have led to the sophisticated self-assembling properties of the glycolipid biosurfactants. 相似文献
89.
Katsuaki Kikuchi Jun Nakamura Yuuya Nagata Hiromu Tsuchida Takahiro Kakuta Tomoki Ogoshi Yasuhiro Morisaki 《化学:亚洲杂志》2019,14(10):1681-1685
Planar chiral building blocks based on 4,7,12,15‐tetrasubstituted [2.2]paracyclophanes were obtained via a synthetic route involving an optical resolution step. Planar chiral enantiomers, comprising two fluorophores that were stacked to form a V‐shaped higher‐ordered structure, were synthesized from these building blocks. The V‐shaped molecules emitted intense circularly polarized luminescence (CPL). Their chiroptical properties were compared with those of X‐shaped molecules bearing the same two fluorophores stacked together. The CPL sign of the X‐shaped molecule was opposite to that of the V‐shaped molecule, which is supported by the theoretical results, indicating that the CPL sign can be controlled by the orientation of the stacked fluorophores. 相似文献
90.