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131.
Sagawa T Sueyoshi R Kawaguchi M Kudo M Ihara H Ohkubo K 《Chemical communications (Cambridge, England)》2004,(7):814-815
A TiO(2)/polymer film on a quartz plate fabricated by a layer-by-layer method was employed for NADH production from NAD(+) with lipoamide dehydrogenase and methyl viologen in Tris-HCl buffer on irradiation with UV light, and the ultra thin film prevented from enzyme deactivating effectively. 相似文献
132.
Determination of indium in metallic tin and cadmium by substoichiometric neutron activation analysis
K. Kudo K. Kobayashi T. Shigematsu K. Fujinaga 《Journal of Radioanalytical and Nuclear Chemistry》1978,43(1):187-198
The paper deseribes the determination of indium in metallic tin and cadmium metals by the direct method, which is a variant
of substoichiometric radioactivation analysis. It is based on substoichiometric extraction of indium diethyldithiocarbamate
into carbon tetrachloride. Indium in tin metal was determined by116mIn (T=54 min), while115mIn (T=4.5 h), formed by the reaction114Cd(n, γ)115Cd was used for cadmium samples. The irradiated sample was dissolved and the radioactivity of116mIn or115mIn, A, was measured. After the separation of indium from the matrix, a known amount of indium, m, was separated substoichiometrically
and the radioactivity, a, was measured. Indium was calculated as Mx=m A/a. If a known amount of the element, M, is added to the irradiated sample in advance, the equation for calculation is
given as Mx-m A/a−M. By this method, indium can be determined without any consideration of self-shielding and secondary nuclear reaction
of the matrix. 相似文献
133.
Yasuyuki Takeda Yusuke Mochizuki Munehiro Tanaka Yoshihiro Kudo Shoichi Katsuta Mikio Ouchi 《Journal of inclusion phenomena and macrocyclic chemistry》1999,33(2):217-231
Formation constants (ML) of 1 : 1 19-crown-6 (19C6) complexes with mono- (M+) and bivalent metal ions (M2+) were determined in water at 25 °C by conductometry. The KML value of 19C6 for M+ and M2+ decreases in the order Rb+ K+ > Tl+ > Na+ = Ag+ > Li+ Cs+ and Pb2+ > Ba2+ > Sr2+ > Cd2+ > Ca2+, respectively. The selectivity for the neighboring alkali metal ions in the periodic table is lower for 19C6 than for 18-crown-6 (18C6) except for the case of Rb+ and Cs+. The same is true for the alkaline earth metal ions. Generally, the KML values of 19C6 with M2+ are greater than those with M+. For Na+ and the ions which are smaller in size than Na+ (Li+, Ca2+, Cd2+), the KML value is larger for 19C6 than for 18C6, but the contrary holds for all the other ions of larger sizes than Na+. The limiting ionic molar conductivity (°) of the 19C6–K+ complex in water at 25 °C was determined to be 43. Although 19C6 is larger than 18C6, the 19C6–K+ complex is much more mobile in water than the 18C6–K+ complex. 相似文献
134.
The excited thioesterase (TE) domain from the vicenistatin polyketide synthase (PKS) efficiently catalyzed the macrolactam formation of the N-acetylcysteamine thioester of the seco-amino acid of the aglycon vicenilactam. This result indicates that the vicenistatin PKS TE domain cyclizes the extended polyketide chain on the ACP domain in the PKS. Furthermore, the simple ethyl ester of the seco-amino acid was also found to be used as a substrate of the TE domain with similar efficiency. 相似文献
135.
Yasuyuki Takeda Takehiro Iwasaki Yoshihiro Kudo Hiroaki Matsuda 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(3-4):303-309
Thermodynamic parameters (H
ex
0
and S
ex
0
) for the overall extractions of monovalent metal (Na, K, Rb, and Tl) picrates with benzo-18-crown-6 (B18C6), and those (H
D,L
0
and S
D,L
0
) for the distribution of B18C6 were determined between chloroform and water. All the extracted B18C6 complexes were l:1:1 complexes (B18C6:metal ion: picrate anion). The H
ex
0
and S
ex
0
values for all the metals are negative. Every extraction of the metal picrate with B18C6 is completely enthalpy driven. The H
D,L
0
and S
D,L
0
values of B18C6 are both positive, and the partition of B18C6 is entirely entropy driven. Enthalpy (H
ex,ip
0
) and entropy changes (S
ex,ip
0
) for ion-pair extractions of B18C6-metal ion complexes with picrate anions were calculated. All the H
ex,ip
0
and S
ex,ip
0
values are negative, and the ion-pair extractions are completely enthalpy driven. 相似文献
136.
Guozhong Wu Yosuke Katsumura Hisaaki Kudoh Yosuke Morita Tadao Seguchi 《Journal of polymer science. Part A, Polymer chemistry》1999,37(10):1541-1548
High‐density polyethylene (HDPE) and low‐density polyethylene (LDPE) were irradiated in vacuo at 30–220 and 30–360°C, respectively, with γ‐rays at doses of 10–400 kGy. Temperature dependence of cross‐linking and gas evolution was investigated. It was found that cross‐linking was the predominant process up to 300°C and the gel point decreased smoothly with temperature. The increase of G(x) with temperature was likely attributed to the temperature effect on addition of radicals to the double bonds present in the polymer. Above 300°C, the gel fraction at a given dose decreased remarkably with temperature and turned to zero at 360°C. The molecular weight variation determined with gel permeation chromatography (GPC) indicated the enhanced degradation at 360°C by radiation. G‐values of H2 increased with temperature and varied with dose. The compositions of the C1–C4 hydrocarbons evolved depended on the structures of side branches. Raising the temperature favored the formation of unsaturated hydrocarbons, and the yield of unsaturated relative to saturated hydrocarbons decreased with dose. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1541–1548, 1999 相似文献
137.
Haruhisa Akiyama Kazuaki Kudo Kunihiro Ichimura 《Macromolecular rapid communications》1995,16(1):35-41
Polymethacrylates with laterally attached azobenzenes were prepared to cause molecular reorientation of this chromophore in their thin films by linearly polarized irradiation with an exposure energy of less than ca. 100 mJ/cm2. A homogeneous alignment was induced by assembling a nematic liquid crystal cell using a substrate plate covered with the photoirradiated films. The alignment direction of the cell was controlled by changing the electric vector of the actinic light. 相似文献
138.
Y. L. Zhao T. Ohtsuki Y. Nishinaka K. Tsukada S. Ichikawa H. Ikezoe Y. Hatuskawa K. Hata M. Tanikawa Z. Qin K. Sueki Y. Oura H. Kudo H. Nakahara 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(1):113-116
Two kinds of scission configurations for certain mass division have been verified by the accurate measurements of fragment
velocities in protoninduced fission of actinides: compact and elongated scission configurations. A correlation between the
binary scission configurations and mass yield distributions reveals that elongated scission configurations are associated
with the symmetric mass distribution and compact scission configurations with the asymmetric mass distribution. The elongation
properties of nuclei at scission in a wide range of actinides fissions are studied. The results suggest that the compact and
the elongated scission configurations in light actinides fission smoothly change to the scission properties of the symmetric
and the asymmetic modes in heavy actinides fission. 相似文献
139.
Hiroto Kudo Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2001,39(1):23-31
The radical polyaddition of N‐4‐vinylbenzoyl‐L ‐cysteine methyl ester (VCM) was carried out in the presence of 2,2′‐azobisisobutyronitrile (AIBN, 3 mol %) as an initiator in dimethyl formamide (DMF) with monomer concentrations of 0.5 and 1.0 M at 60 °C for 20 h under nitrogen atmosphere to afford the corresponding polymers [poly(VCM), PVCM] with number‐average molecular weights (Mn)'s of 5300 and 18,000 in 92 and 95% yields, respectively. The obtained polymers had a heterotelechelic structure with thiol and olefin end moieties. The radical polymerization of methyl methacrylate and trityl methacrylate was carried out in the presence of PVCM with AIBN (3 mol %) as an initiator in DMF at 60 °C for 20 h to afford the block copolymers with Mn values in the range of 13,000–26,800 in good yields. PVCM [Mn = 18,000; polydispersity (Mw/Mn) = 1.56] was treated with 4 equiv of NaOH aq. (1.0 M) to afford the polymer having carboxyl groups in the side chain with a Mn of 17,300 and Mw/Mn of 1.88 in 95% yield and was also oxidized to polysulfoxide and polysulfone with 4 equiv of H2O2 per sulfide unit in CH2Cl2 (1.0 M) for 20 h. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 23–31, 2001 相似文献
140.