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941.
Modern statistical data analysis often requires powerful computers. Parallel computing is a technique to realize such a computer
system. Although many “low-level” software technologies for parallel computing have been developed, they are not easy to use
for statisticians who are accustomed to “high-level” statistical languages. In this paper, we describe high-level parallel
computing functions in a statistical analysis system called Jasp. We implemented them mainly considering ease of use. 相似文献
942.
Johansson J Saito S Meno T Nakano H Ueda M Semba K Takayanagi H 《Physical review letters》2006,96(12):127006
We have observed the coherent exchange of a single energy quantum between a flux qubit and a superconducting LC circuit acting as a quantum harmonic oscillator. The exchange of an energy quantum is known as the vacuum Rabi oscillation: the qubit is oscillating between the excited state and the ground state and the oscillator between the vacuum state and the first excited state. We also show that we can detect the state of the oscillator with the qubit and thereby obtained evidence of level quantization of the LC circuit. Our results support the idea of using oscillators as couplers of solid-state qubits. 相似文献
943.
Kohri H Ahn DS Ahn JK Akimune H Asano Y Chang WC Date' S Ejiri H Fukui S Fujimura H Fujiwara M Hasegawa S Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kumagai N Makino S Mart T Matsuda T Matsumura T Matsuoka N Mibe T Miyabe M Miyachi Y Morita M Muramatsu N Nakano T Niiyama M Nomachi M Ohashi Y Ohkuma H Ooba T Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu A Shimizu H Sugaya Y Sumihama M Toi Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T 《Physical review letters》2006,97(8):082003
Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations. 相似文献
944.
In this article novel sulfonated block copolyimides with various diamine compositions and block chain lengths were synthesized by chemical imidization using a two‐pot procedure. The proton conductivities of the block copolyimide membranes were measured as functions of the relative humidity and temperature using four‐point‐probe electrochemical impedance spectroscopy. The proton conductivity of the membranes strongly depended on the block chain lengths and increased with an increase in the block chain lengths. The proton conductivity of NTDA‐BDSA‐b‐6FAP (112/48) as the block copolyimide membrane was approximately 0.35 S cm−1 which indicated a higher value when compared to that determined for Nafion®. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
945.
Motoyoshi Nakano Yudai Ishimura Riki Hotta Daiki Hebiguchi Toshiaki Nagata Fuminori Misaizu 《化学物理学报》2019,(2)
本文通过离子迁移质谱法研究了氧化钠团簇阳离子(Na_nO_m~+,n≤11)的稳定结构.质谱结果表明化学计量组成Na(Na_2O)_((n-1)/2)~+(n=3、5、7、9和11)系列是稳定的,并且NaO(Na_2O)_((n-1)/2)~+(n=5、7、9和11)系列作为二级稳定系列.为了获得这些团簇离子的结构,通过离子迁移率测量实验测定离子和氦缓冲气体之间的碰撞截面.同时计算了这些组合物优化结构的理论碰撞截面.结果表明,Na(Na_2O)_((n-1)/2)~+和NaO(Na_2O)_((n-1)/2)~+的结构除了n=9之外,其它具有相似结构框架.Na(Na_2O)_((n-1)/2)~+所有的化合键位于钠和氧之间.另一方面,NaO(Na_2O)_((n-1)/2)~+中除了Na-O键之外,还存在一个O-O氧键,表明NaO(Na_2O)_((n-1)/2)~+具有过氧化物离子(O_2~(2-))作为Na(Na_2O)_((n-1)/2)~+的氧化物离子(O~(2-))的替代物.Na(Na_2O)_((n-1)/2)~+和NaO(Na_2O)_((n-1)/2)~+两种稳定系列都是闭壳组合物.这些闭壳特征对氧化钠簇阳离子的稳定性具有强烈影响. 相似文献
946.
Kenichiro Todoroki Tatsuki Nakano Yasuhiro Eda Kaname Ohyama Hideki Hayashi Daiki Tsuji Jun Zhe Min Koichi Inoue Naoki Iwamoto Atsushi Kawakami Yukitaka Ueki Kunihiko Itoh Toshimasa Toyo'oka 《Analytica chimica acta》2016
This study presents two simple and rapid methods for the quantification of therapeutic mAbs based on LC. Two mAbs (bevacizumab and infliximab) in plasma samples were purified using magnetic beads immobilized with a commercially-available idiotype antibody for each mAb. Purified mAbs were separated with HT-RPLC and detected with their native fluorescence. Using immunoaffinity beads, each mAb was selectively purified and detected as a single peak in the chromatogram. The HT-RPLC achieved good separation for the mAbs with sharp peaks within 20 min. The calibration curves of the two mAbs ranged from 1 to 20 μg mL−1 (bevacizumab) and 1–10 μg mL−1 (infliximab), and they had strong correlation coefficients (r2 > 0.998). The LOD of bevacizumab and infliximab was 0.07 and 0.15 μg mL−1, and the LLOQ of bevacizumab and infliximab was 0.12 and 0.25 μg mL−1, respectively. Thus, the sensitivities were sufficient for clinical analysis. Immunoaffinity purification with HT-RPLC produced a selective and accurate bioanalysis without an LC-MS/MS instrument. Both methods could become general-purpose analytical methods and complement the results obtained with conventional LBA. 相似文献
947.
T Kawaguchi S Fukushima M Ohmura M Mishima M Nakano 《Chemical & pharmaceutical bulletin》1989,37(7):1944-1945
The enzymatic and chemical stability of three 2',3'-dideoxy-2',3'-didehydropyrimidine nucleosides has been studied. Chemical degradtion of the analogues was measured in the pH range of 1.0-9.0. 2',3'-Dideoxy-2',3'-didehydrocytidine (DDCN) degraded rapidly under acidic conditions, but the chemical stability was greater under basic conditions. The chemical degradation of 2',3'-dideoxy-2',3'-didehydrouridine (DDUN) and 2',3'-dideoxy-2',3'-didehydrothymidine (DDTN) was not pH dependent and was faster than that of cytarabine. Enzymatic degradation of DDCN, DDUN and DDTN was not observed in human plasma, though cytarabine was degraded enzymatically under the same conditions. DDCN was also not degraded in the presence of mouse kidney cytidine deaminase. 相似文献
948.
Abstract— The apparent K m for O2 in the photoreduction of molecular oxygen by spinach class II chloroplasts and photosystem I subchloroplast fragments was determined. In both cases, a value of 2 ∼ 3 μ M O2 was obtained. The reaction rate constant between O2 and P-430, the primary electron acceptor of PS I, is estimated to be ∼ 1.5 × 107 M -1 s-1 and the factors affecting the production of superoxide by the photoreduction of O2 in chloroplasts are discussed. Preliminary evidence is presented indicating the occurrence of an azide-insensitive scavenging system for H2 O2 in chloroplast stroma. 相似文献
949.
A Phosphole Oxide Based Fluorescent Dye with Exceptional Resistance to Photobleaching: A Practical Tool for Continuous Imaging in STED Microscopy 下载免费PDF全文
Dr. Chenguang Wang Prof. Dr. Aiko Fukazawa Prof. Dr. Masayasu Taki Dr. Yoshikatsu Sato Prof. Dr. Tetsuya Higashiyama Prof. Dr. Shigehiro Yamaguchi 《Angewandte Chemie (International ed. in English)》2015,54(50):15213-15217
The development of stimulated emission depletion (STED) microscopy represented a major breakthrough in cellular and molecular biology. However, the intense laser beams required for both excitation and STED usually provoke rapid photobleaching of fluorescent molecular probes, which significantly limits the performance and practical utility of STED microscopy. We herein developed a photoresistant fluorescent dye C‐Naphox as a practical tool for STED imaging. With excitation using either a λ=405 or 488 nm laser in protic solvents, C‐Naphox exhibited an intense red/orange fluorescence (quantum yield ΦF>0.7) with a large Stokes shift (circa 5900 cm?1). Even after irradiation with a Xe lamp (300 W, λex=460 nm, full width at half maximum (FWHM)=11 nm) for 12 hours, 99.5 % of C‐Naphox remained intact. The high photoresistance of C‐Naphox allowed repeated STED imaging of HeLa cells. Even after recording 50 STED images, 83 % of the initial fluorescence intensity persisted. 相似文献
950.
Environment‐Sensitive Fluorescent Probe: A Benzophosphole Oxide with an Electron‐Donating Substituent 下载免费PDF全文
Eriko Yamaguchi Chenguang Wang Prof. Dr. Aiko Fukazawa Prof. Dr. Masayasu Taki Dr. Yoshikatsu Sato Taeko Sasaki Dr. Minako Ueda Prof. Dr. Narie Sasaki Prof. Dr. Tetsuya Higashiyama Prof. Dr. Shigehiro Yamaguchi 《Angewandte Chemie (International ed. in English)》2015,54(15):4539-4543
Electron‐donating aryl groups were attached to electron‐accepting benzophosphole skeletons. Among several derivatives thus prepared, one benzophosphole oxide was particularly interesting, as it retained high fluorescence quantum yields even in polar and protic solvents. This phosphole‐based compound exhibited a drastic color change of its fluorescence spectrum as a function of the solvent polarity, while the absorption spectra remained virtually unchanged. Capitalizing on these features, this phosphole‐based compound was used to stain adipocytes, in which the polarity of subcellular compartments could then be discriminated on the basis of the color change of the fluorescence emission. 相似文献