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391.
3,7-二取代双环[3,3,1]壬烷衍生物具有许多有趣的反应特异性,可合成各种官能性金刚烷衍生物。本文以1-金刚烷醇为原料经二步反应合成7-亚甲基双环[3,3,1]壬烷-3-酮。再用催化量四氧化锇进行氧化几乎定量地得到7-羟甲基-7-羟基双环[3,3,1]壬烷-3-酮(9)。9用对甲苯磺酰氯处理得11,然后转换成1-羟基-4-原金刚烷酮(8)。根据光谱数据分析,(9)有一互变异构体(10),研究表明10的存在对合成8没有影响。预计8可以作为合成各种三取代金刚烷的原料。 相似文献
392.
393.
基于地对空高光谱观测获取大气CO2柱浓度(大气中CO2的垂直总含量)数据是验证和改进卫星高光谱观测反演CO2浓度的重要数据源之一,而目前在中国还没有基于地面光谱观测进行大气CO2柱浓度反演研究的报告。利用光谱分析仪与太阳跟踪仪等构成的地面观测系统在中国内蒙古锡林郭勒草原进行了地对空高光谱观测,基于高光谱观测数据反演了大气CO2柱浓度。在基于1.6 μm大气CO2的光谱吸收特征进行CO2浓度反演过程中,评价分析了观测光谱的波长漂移和气象参数对大气CO2柱浓度反演精度的影响。结果显示观测期间平均大气CO2柱浓度为390.9 μg·mL-1。波长的漂移将会导致反演浓度值整体偏低;波长漂移从-0.012~0.042 nm范围时,将会导致1 μg·mL-1以上的偏差。同时,研究发现光谱透过率在6 357~6 358,6 360~6 361和6 363~6 364 cm-1谱段敏感于气象参数的变化。对比利用与光谱观测同时和非同时观测的气象参数进行的浓度反演结果发现,非同时观测气象参数的利用引起的浓度偏差最小在0.11 μg·mL-1,最大可达4 μg·mL-1;本论文的分析结果对基于光谱反演CO2柱浓度算法的改进有着一定的参考价值。 相似文献
394.
The utility of N-sulfonylimines as radical acceptors was investigated under the different reaction conditions such as the stannyl radical-mediated addition reaction, the triethylborane-mediated tin-free radical reaction, and the zinc-mediated aqueous-medium radical reaction. The alkyl radical addition reaction of N-sulfonylimines proceeded effectively without the activation by Lewis acid. These reactions were successfully extended to one-pot reactions for preparing a wide range of amine derivatives. 相似文献
395.
Kazuya Fukunaga Kazuaki Kouyama Masafumi Hashimoto Hideyuki Kunugita Kazuhiro Ema Akihiko Kikuchi Katsumi Kishino 《Journal of luminescence》2009,129(12):1735-1738
We have measured the optical properties of wurtzite InN nanocolumns and film by photoluminescence (PL) measurements at temperatures from 5 to 300 K and analyzed the PL spectra by fitting with the free-electron recombination bound (FERB) model. For the top-linked InN nanocolumns, we observed strong PL intensity compared to the InN film sample. The PL spectra were asymmetrical with low-energy tails and a red-shift of the PL peak energy position was observed with increasing temperature. However, for the separated InN nanocolumns, we observed weak PL intensity and symmetrical PL spectra. Analyzing the spectra shape of the top-linked InN nanocolumns at 5 K using the FERB model, we evaluated the intrinsic bandgap energy and carrier density of InN nanocolumns to be 0.69 eV and 2.5×1017 cm−3, respectively. 相似文献
396.
Dr. Ming Zhang Dr. Kenji Watanabe Masafumi Tsukamoto Ryozo Shibuya Dr. Hiroyuki Morimoto Dr. Takashi Ohshima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3937-3941
An increased supply of scarce or inaccessible natural products is essential for the development of more sophisticated pharmaceutical agents and biological tools, and thus the development of atom‐economical, step‐economical and scalable processes to access these natural products is in high demand. Herein we report the development of a short, scalable total synthesis of (?)‐α‐kainic acid, a useful compound in neuropharmacology that is, however, limited in supply from natural resources. The synthesis features sequential platinum‐catalyzed direct allylic aminations and thermal ene‐cyclization, enabling the gram‐scale synthesis of (?)‐α‐kainic acid in six steps and 34 % overall yield. 相似文献
397.
Masafumi Yoshino 《manuscripta mathematica》2012,137(3-4):441-455
We shall show the solvability of semilinear Fuchsian partial differential systems in a multi-sectorial domain. Our equation contains a linearizing equation of a singular vector field to its linear part when so-called small denominators occur. We will show the existence of an analytic solution in a multi-sectorial domain without assuming any Diophantine condition. 相似文献
398.
Cover Picture: Enantioselective Addition of a 2‐Alkoxycarbonyl‐1,3‐dithiane to Imines Catalyzed by a Bis(guanidino)iminophosphorane Organosuperbase (Angew. Chem. Int. Ed. 52/2015)
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399.
Dr. Yukihiro Yoshida Kazuhide Isomura Prof. Hideo Kishida Yoshihide Kumagai Prof. Motohiro Mizuno Dr. Masafumi Sakata Dr. Takashi Koretsune Dr. Yoshiaki Nakano Prof. Hideki Yamochi Dr. Mitsuhiko Maesato Prof. Gunzi Saito 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):6023-6030
Coronene, which is the smallest D6h‐symmetric polycyclic aromatic hydrocarbon, attracts particular attention as a basic component of electronic materials because it is the smallest fragment of graphene. However, carrier generation by physical methods, such as photo‐ or electric field‐effect, has barely been studied, primarily because of the poor π‐conduction pathway in pristine coronene solid. In this work we have developed unprecedented π‐stacking columns of cationic coronene molecules by electrochemical hole‐doping with polyoxometallate dianions. The face‐to‐face π–π interactions as well as the partially charged state lead to electrical conductivity at room temperature of up to 3 S cm?1, which is more than 10 orders of magnitude higher than that of pristine coronene solid. Additionally, the robust π–π interactions strongly suppress the in‐plane rotation of the coronene molecules, which has allowed the first direct observation of the static Jahn–Teller distortion of cationic coronene molecules. 相似文献
400.
3,6-disubstituted-2-nitrotoluenes were obtained in moderate yield by methylation of 2,5-disubstituted nitrobenzenes with dimethylsulfonium methylide in DMSO-THF mixture. 相似文献