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111.
T. Shinohara A. Furusawa S. Hayashibe M. Kanazawa M. Sato 《Journal of magnetism and magnetic materials》1987,70(1-3):282-284
The time integral γ-γ perturbed angular correlation has been measured on 156Gd nuclei in TbFe2, TbFe3, TbCo2 and TbCo3 compounds.
An obvious correlation is indicated between the hyperfine fields at Gd and Tb nuclei in corresponding compounds, and experimental results are discussed. 相似文献
112.
113.
Brittle-fracture propagation tests were carried out to find relations among the speed of crack propagation, the dynamic-stress distribution, the test temperature and the applied stress. These tests were performed at low temperatures so that the behavior of the crack propagation was fully elastic. The test results were compared with the theoretical calculations and some considerations were made on the surface plastic work. 相似文献
114.
T. Shinohara A. Furusawa S. Hayashibe M. Kanazawa M. Sato 《Hyperfine Interactions》1987,36(3-4):243-251
Time integral γ-γ angular correlation measurements have been made on156Gd in Tb-3d metal compounds, TbFe2, TbFe3, TbCo2 and TbCo3, using two Ge(Li) detetctors. From the observation of a linear relation between magnetic hyperfine fields at Gd and Tb nuclei
in corresponding compounds, it is inferred that crystalfield induced variations of the Tb moment are negligible. The experimental
results are discussed in terms of the conduction electron polarization caused by the magnetic moment of 3d metals. 相似文献
115.
Nagase K Kobayashi J Kikuchi A Akiyama Y Annaka M Kanazawa H Okano T 《Langmuir : the ACS journal of surfaces and colloids》2008,24(19):10981-10987
We have prepared poly( N-isopropylacrylamide) (PIPAAm) brush-grafted surfaces with varied temperature-responsive hydrophobic properties through surface-initiated atom transfer radical polymerization (ATRP). These temperature-responsive surfaces were characterized by chromatographic analysis using modified silica beads as a chromatographic stationary phase in aqueous mobile phase. Mixed silane self-assembled monolayers (SAMs) comprising ATRP initiator and silanes with various terminal functional groups were formed on the silica bead surfaces. IPAAm was then polymerized by ATRP using the CuCl/CuCl2/Me6TREN catalyst system in 2-propanol at 25 degrees C for 16 h. The chromatographic retention behavior of steroids on the resulting PIPAAm brushes made on more polar silane components was distinct from that on more apolar silane interfaces. Retention times for steroids on PIPAAm mixed apolar silane graft interfaces were significantly longer than those on analogous polar silane interfaces due to enhanced dehydration of PIPAAm brushes on apolar silane-grafted surfaces. Changes in retention factor, k', on polar silane PIPAAm-grafted interfaces were relatively large compared to that on apolar PIPAAm grafted interfaces due to larger hydration/dehydration alterations of grafted PIPAAm brushes on the former surfaces. Applied step-temperature gradients from 50 to 10 degrees C show that PIPAAm brushes on polar silane interfaces tend to hydrate more, leading to shorter retention times. In conclusion, the polarity of the grafted interface significantly influences the grafted PIPAAm brush hydration/dehydration characteristics and subsequently also the temperature-modulated separation of bioactive compounds in all-aqueous chromatography. 相似文献
116.
A scaleable synthetic route is described to obtain 2-(4-acetylpiperadin-1-yl)-6-[3,5-bis(trifluoromethyl)phenylmethyl]-4-(2-methylphenyl)-6,7,8,9-tetrahydro-5H-pyrimido[4,5-b][1,5]oxazocin-5-one (1, KRP-103) as a neurokinin (NK)(1) antagonist. The key step in the synthesis is the intramolecular cyclization of N-[3,5-bis(trifluoromethyl)phenylmethyl]-N-(3-hydroxypropyl)-4-chloro-6-(2-methylphenyl)-2-methylthiopyrimidine-5-carboxamide (15) which was obtained by amide formation between 4-(2-methylphenyl)-2-methylthio-6-oxo-1,6-dihydropyrimidine-5-carboxylic acid (8) and 3-[3,5-bis(trifluoromethyl)phenylmethylamino]-1-propanol (3). Treatment of 15 with 1,8-diazabicyclo[5,4,0]undec-7-ene provided 6-[3,5-bis(trifluoromethyl)phenylmethyl]-4-(2-methylphenyl)-2-methylthio-6,7,8,9-tetrahydro-5H-pyrimido[4,5-b][1,5]oxazocin-5-one (6). This intermediate (6) is transformed into the candidate compound (1) by two steps; oxidation, and substitution reaction of the resultant sulfone (7) with 1-acetylpiperazine. This synthetic method is free of chromatographic purification and is amenable to large scale synthesis. 相似文献
117.
Sato Y Moriyama R Choi SW Kano A Maruyama A 《Langmuir : the ACS journal of surfaces and colloids》2007,23(1):65-69
We have demonstrated that cationic comb-type copolymers consisting of a polycation backbone and abundant grafts of water-soluble polymers stabilize DNA hybrids. Furthermore, the copolymers were found to accelerate strand exchange reaction between a double-stranded DNA and its complementary single-stranded DNA. In this article, we investigated the effects of PLL-g-Dex on base pairs of a self-complementary DNA octamer, d(GGAATTCC). The soluble interpolyelectrolyte complex (IPEC) between the DNA and copolymer allowed us to characterize the complex by using spectroscopic methods under physiological ionic condition. Chemical shifts of nucleobase proton signals were not changed by PLL-g-Dex. Furthermore, the copolymer slightly changed the von't Hoff DeltaH accompanying the helix-coil transition of the octamer. These results indicated that the base pairs of the duplex DNA in the IPEC were not perturbed by the polycationic copolymer. It was obviously shown by temperature dependencies of proton and phosphorus NMR spectra that DNA/copolymer interaction was considerably enhanced in response to ds DNA formation. An increase in the density and total number of DNA negative charges upon hybrid formation likely caused the higher affinity of the copolymer with the ds form over that of the copolymer with the ss form. The IPEC formation of CCCs with DNA, however, seems highly sensitive to the coil-helix transition of the DNA. 相似文献
118.
We have investigated the immersion-angle dependence of the series resonant-frequency shift, ΔF, of the quartz crystal microbalance, QCM, in a Newtonian liquid from the point of view of the supplied electric power level. In the low electric power levels, the immersion-angle dependence and the transition phenomenon of the ΔF are observed. However, when the higher electric power levels are supplied to the QCM, the region of the transition phenomenon of the ΔF decreases rapidly with an increase in the electric power level and disappears above 1.5 dBm. That is, above 1.5 dBm, the ΔF values have only the values of 90° immersion angle in all immersion angles. We suggest that the electric power is very important factor for the ΔF in a liquid. 相似文献
119.
M. Mihara K. Matsuta D. Nishimura T. Nagatomo R. Matsumiya S. Momota T. Ohtsubo T. Izumikawa D. M. Zhou Y. N. Zheng M. Ogura H. Akai J. Komurasaki M. Fukuda D. Ishikawa Y. Nojiri H. Hirano S. Takahashi R. Watanabe T. Kubo S. Y. Zhu A. Kitagawa M. Kanazawa S. Sato M. Torikoshi T. Sumikama T. Minamisono J. R. Alonso G. F. Krebs T. J. M. Symons 《Hyperfine Interactions》2007,178(1-3):83-86
The spin-lattice relaxation times T 1 for short-lived β emitters 25Al(I?=?5/2, T 1/2?= 7.2 s) and 28P(I?=?3, T 1/2?= 270 ms) in Pt were measured by means of the β-NMR technique. As a result, T 1[25Al in Pt] = (1.1 $^{+\ 0.7}_{-\ 0.3})$ s and T 1[28P in Pt] >0.5 s were obtained at temperatures of 17 and 20 K, respectively. The Knight shifts were estimated from the Korringa relation, which were evaluated by comparing to the first principle calculations. 相似文献
120.
Efficient Total Synthesis of Bongkrekic Acid and Apoptosis Inhibitory Activity of Its Analogues 下载免费PDF全文
Dr. Kenji Matsumoto Masaki Suyama Satoshi Fujita Takuya Moriwaki Yukiko Sato Yoshifumi Aso Satoshi Muroshita Hiroshi Matsuo Keishi Monda Dr. Katsuhiro Okuda Dr. Masato Abe Dr. Hiroyuki Fukunaga Prof. Arihiro Kano Prof. Mitsuru Shindo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11590-11602
Bongkrekic acid (BKA), isolated from the bacterium Burkholderia cocovenenans, is an inhibitor of adenine nucleotide translocator, which inhibits apoptosis, and is thus an important tool for the mechanistic investigation of apoptosis. An efficient total synthesis of BKA has been achieved by employing a three‐component convergent strategy based on Kocienski–Julia olefination and Suzuki–Miyaura coupling. It is noteworthy that segment B has been prepared as a new doubly functionalized coupling partner, which contributes to shortening of the number of steps. Torquoselective olefination with an ynolate has also been applied for the efficient construction of an unsaturated ester. Furthermore, it is revealed that 1‐methyl‐2‐azaadamantane N‐oxyl is an excellent reagent for final oxidation to afford BKA in high yield. Based on the total synthesis, several BKA analogues were prepared for structure–activity relationship studies, which indicated that the carboxylic acid moieties were essential for the apoptosis inhibitory activity of BKA. More easily available BKA analogues with potent apoptosis inhibitory activity were also developed. 相似文献