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101.
Amane Mochizuki Michie Sakamoto Masahiro Yoshioka Takahiro Fukuoka Kazumasa Takeshi Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2000,38(2):329-336
A novel photosensitive polymer based on end‐capped polycarbodiimide (E‐PCD) and the photoamine generator N‐{[(4,5‐dimethoxy‐2‐nitrobenzyl)oxy]carbonyl}‐2,6‐dimethylpiperidine (1) was developed. The E‐PCD was prepared by polycondensation of tolylene‐2,4‐diisocyanate in the presence of 3‐methy‐1‐phenyl‐2‐phospholene‐1‐oxide as a catalyst. The reaction of carbodiimide and secondary amine was studied. The nucleophilic addition of amine to the carbodiimide moiety proceeded smoothly and provided a guanidine base that acted as a crosslinking agent. A lithographic evaluation of the system of E‐PCD and 1 revealed that the dissolution rate of the exposed area after the postexposure bake decreased drastically, although no obvious change of the dissolution rate in the unexposed area was observed. The E‐PCD containing 10 wt % 1 functioned as a negative working photosensitive polymer when it was exposed to 365‐nm UV light, postbaked at 120 °C for 5 min, and developed with toluene at 25 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 329–336, 2000 相似文献
102.
Atsushi Narumi Yutaka Miura Issei Otsuka Shin Yamane Yoshikazu Kitajyo Toshifumi Satoh Akira Hirao Noriaki Kaneko Harumi Kaga Toyoji Kakuchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(16):4864-4879
This article describes that glucose, maltose, maltotriose, maltotetraose, maltopentaose, and maltohexaose ( a , b , c , d , e , and f , respectively) were introduced into the initiating chain‐end of polystyrene (PSt) through the 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO)‐mediated radical polymerization. A series of glycoconjuaged TEMPO‐adducts, 1a–f , was synthesized and used as the initiators for the polymerization of styrene (St) for 6 h at 120 °C to afford the end‐functionalized PSt's with the acetyl saccharides, 2a–f , in the yields of 37–43%. For 2a–f obtained by the polymerizations using the [St]/[ 1 ] of 125, 250, and 500, the number‐average molecular weights determined by size exclusion chromatography (SEC), Mn,SEC's, were 4800–6300, 8800–10,600, and 18,400–25,200, respectively, which fairly agreed with the predicted values. The end‐functionalized PSt's with saccharides, 3a–f , which were obtained from the deacetylation of 2a–f using sodium methoxide in dry THF, formed the polymeric reverse micelles consisting of a saccharide‐core and a PSt‐shell in chloroform and toluene. The static laser light scattering (SLS) measurements provided the average molar mass of the aggregates in toluene, Mw,SLS's, which ranged from 7.50 × 104 to 1.77 × 105 for 3a , from 1.90 × 105 to 4.93 × 105 for 3b , from 4.41 × 105 to 7.21 × 105 for 3c , from 5.85 × 105 to 8.51 × 105 for 3d , from 7.55 × 105 to 8.53 × 105 for 3e , and from 8.54 × 105 to 9.26 × 105 for 3f . The aggregation numbers, Nagg's, which were calculated from the Mw,SLS's, were from 7 to 24 for 3a , from 20 to 37 for 3b , from 34 to 89 for 3c , from 39 to 116 for 3d , from 41 to 145 for 3e , and from 31 to 146 for 3f . It was confirmed that the aggregation property, such as the Mw,SLS or Nagg values, was strongly related to the polymerization degrees of St (DP's) or the number of the glucose residues (n's) for 3a–f . © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4864–4879, 2006 相似文献
103.
104.
105.
Ab initio calculations of structures and interaction energies of toluene dimers including CCSD(T) level electron correlation correction 总被引:1,自引:0,他引:1
The intermolecular interaction energy of the toluene dimer has been calculated with the ARS-F model (a model chemistry for the evaluation of intermolecular interaction energy between ARomatic Systems using Feller's method), which was formerly called as the AIMI model III. The CCSD(T) (coupled cluster calculations with single and double substitutions with noniterative triple excitations) interaction energy at the basis set limit has been estimated from the second-order Moller-Plesset perturbation interaction energy at the basis set limit obtained by Feller's method and the CCSD(T) correction term obtained using a medium-size basis set. The cross (C(2)) dimer has the largest (most negative) interaction energy (-4.08 kcal/mol). The antiparallel (C(2h)) and parallel (C(S)) dimers (-3.77 and -3.41 kcal/mol, respectively) are slightly less stable. The dispersion interaction is found to be the major source of attraction in the toluene dimer. The dispersion interaction mainly determines the relative stability of the stacked three dimers. The electrostatic interaction of the stacked three dimers is repulsive. Although the T-shaped and slipped-parallel benzene dimers are nearly isoenergetic, the stacked toluene dimers are substantially more stable than the T-shaped toluene dimer (-2.62 kcal/mol). The large dispersion interaction in the stacked toluene dimers is the cause of their enhanced stability. 相似文献
106.
107.
Haruo Ogura Takanori Kobayashi Keiko Shimizu Kazumasa Kawabe Kazuyoshi Takeda 《Tetrahedron letters》1979,20(49):4745-4746
A convenient reagent for active ester synthesis --N,N′-disucinimidyl carbonate-- was prepared. This reagent was useful for the preparation of active esters and peptides in stead of dicyclohexylcarbodiimide. 相似文献
108.
Kamada A Sasaki A Kitazawa N Okabe T Nara K Hamaoka S Araki S Hagiwara H 《Chemical & pharmaceutical bulletin》2004,52(1):79-88
New types of selective estrogen receptor modulators (SERMs) were synthesized and evaluated for their binding affinity and biological effect on reproductive cells. A proposed lead structure (B) was derivatized to provide compounds 30 and 44, which showed good estrogen-receptor binding affinity (K(i) values: 6.3 and 10 nM, respectively), as well as minimal impact on mammary and uterine carcinoma cells. Introduction of an alkyl group in the core structure considerably enhanced receptor-binding affinity of the compounds tested. Synthesis and structure-activity relationships of these compounds are described. 相似文献
109.
Koishi T Yoo S Yasuoka K Zeng XC Narumi T Susukita R Kawai A Furusawa H Suenaga A Okimoto N Futatsugi N Ebisuzaki T 《Physical review letters》2004,93(18):185701
We report large-scale atomistic simulation of midrange nanoscale hydrophobic interaction, manifested by the nucleation of nanobubble between nanometer-sized hydrophobes at constrained equilibrium. When the length scale of the hydrophobes is greater than 2 nm, the nanobubble formation shows hysteresis behavior resembling the first-order transition. Calculation of the potential of mean force versus interhydrophobe distance provides a quantitative measure of the strength of the nanoscale hydrophobic interaction. 相似文献
110.
We introduce the notion of hyper-self-duality for Bose-Mesner algebras as a strengthening of formal self-duality. Let
denote a Bose-Mesner algebra on a finite nonempty set X. Fix p X, and let
and
denote respectively the dual Bose-Mesner algebra and the Terwilliger algebra of
with respect to p. By a hyper-duality of
, we mean an automorphism of
such that
for all
; and
is a duality of
.
is said to be hyper-self-dual whenever there exists a hyper-duality of
. We say that
is strongly hyper-self-dual whenever there exists a hyper-duality of
which can be expressed as conjugation by an invertible element of
. We show that Bose-Mesner algebras which support a spin model are strongly hyper-self-dual, and we characterize strong hyper-self-duality via the module structure of the associated Terwilliger algebra. 相似文献