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81.
82.
Reaction of fused 3-(2-bromoethyl)pyrimidin-4(3H)-ones with primary alkylamines gave abnormal fused 3-alkyl-4-alkyliminopyrimidines via a new rearrangement, as well as normal substituted 3-(2-alkylaminoethyl) derivatives. Antidepressive evaluation of these compounds was performed by antireserpine action and one compound exhibited the positive activity comparable to imipramine. 相似文献
83.
Mari Hashimoto Shunichi Fujii Hiroaki Imoto Kensuke Naka 《Journal of polymer science. Part A, Polymer chemistry》2019,57(22):2260-2266
We first time prepared main‐chain type cage octasilsesquioxane (T8) containing coordination polymers based on transition metal complexes with a bis‐Schiff base T8 ligand ( bis‐SA‐T 8 ), which was prepared from para‐bis(3‐aminopropyl)hexaisobutyl‐substituted T8 cage ( bis‐T 8 ) with salicylaldehyde. A mono‐Schiff base T8 ligand ( SA‐T 8 ) was prepared from 3‐aminopropylheptaisobutyl‐substituted T8 cage ( mono‐T 8 ) with salicylaldehyde. Coordination of bis‐SA‐T 8 with Cu2+ and Zn2+ in a solution as well as the film state was confirmed by the d–d transition appearing as broad shoulder on the longer wavelength at around 600 nm and the fluorescence at around 440–470 nm, respectively. The resulting metallosupramolecular polymers gave optically transparent films in the visible region by a casting method. However, opaque green and whitish films were obtained in the case of the Cu2+ and Zn2+ complexes with SA‐T 8 , respectively. The thermal stabilities of the metallosupramolecular polymers were higher than those of the corresponding metal complexes of SA‐T 8 . © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2260–2266 相似文献
84.
Dr. Hiroaki Imoto Prof. Dr. Kensuke Naka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(8):1883-1894
Organoarsenic chemistry was actively studied until the middle of 20th century. Although various properties of organoarsenic compounds have been computationally predicted, for example, frontier orbital levels, aromaticity, and inversion energies, serious concern to the danger of their synthetic processes has restricted experimental studies. Conventional synthetic routes require volatile and toxic arsenic precursors. Recently, nonvolatile intermediate transformation (NIT) methods have been developed to safely access functional organoarsenic compounds. Important intermediates in the NIT methods are cyclooligoarsines, which are prepared from nonvolatile inorganic precursors. In particular, the new approach has realized experimental studies on conjugated arsenic compounds: arsole derivatives. The elucidation of their intrinsic properties has triggered studies on functional organoarsenic chemistry. As a result, various kinds of arsenic-containing π-conjugated molecules and polymers have been reported for the last few years. In this minireview, progress of this recently invigorated field is overviewed. 相似文献
85.
Koichi Kamiya Kensuke Miura Dr. Hiroaki Itoh Prof. Dr. Masayuki Inoue 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):1088-1093
Yaku′amide B ( 1 ) inhibits cancer cell growth through a unique mechanism of action. Compound 1 binds to mitochondrial FoF1-ATP synthase, inhibits ATP production, and enhances ATP hydrolysis. The presence of one (E)- and two (Z)-α,β-dehydroisoleucines (ΔIle) in the linear 13-mer sequence is the most unusual structural feature of 1 . To uncover the biological importance of these residues, we synthesized 1 and its seven E/Z isomers 2 – 8 by devising a new divergent solid-phase strategy. Both the (E)- and (Z)-ΔIle residues were stereoselectively constructed by traceless Staudinger ligation on resin to ultimately deliver 1 – 8 . All isomers 2 – 8 displayed effects on the inhibition of cell growth and ATP production, and enhanced ATP hydrolysis, thus indicating that 2 – 8 share the same mode of action as 1 . The least potent isomer, 8 , was isomeric at three ΔIle residues of the most potent 1 . These findings together indicate that the E/Z stereochemistry of the three ΔIle residues controls the magnitude of the biological functions of 1 . 相似文献
86.
Matsumoto Yutaka Takeo Yoko Egawa Satoru Yamaguchi Gota Yokomae Shunya Takei Masashi Yumoto Hirokatsu Koyama Takahisa Ohashi Haruhiko Tono Kensuke Yabashi Makina Mimura Hidekazu Kimura Takashi 《Optical Review》2022,29(1):7-12
Optical Review - A microfluidic device was developed for coherent diffraction imaging using an X-ray free-electron laser (XFEL-CDI). Liquid samples, which are separately packed in reservoirs of the... 相似文献
87.
The H(2)C=CD isotopic species of vinyl radical produced in a supersonic jet expansion by ultraviolet laser photolysis was studied by millimeter-wave spectroscopy. Due to the tunneling motion of the α deuteron, the ground state is split into two components, 0(+) and 0(-). Tunneling-rotation transitions connecting the lower (0(+)) and upper (0(-)) components of the tunneling doublet were observed in the frequency region of 184-334 GHz, including three R- and two Q-branch transitions. Three and two pure rotational transitions in the K(a)=0 and 1 stacks, respectively, were also observed for each of the 0(+) and 0(-) states in the frequency region of 52-159 GHz. Least-squares analysis of the observed frequencies for the tunneling-rotation and pure rotational transitions with well resolved hyperfine structures yielded a set of precise molecular constants, among which the tunneling splitting in the ground state was determined to be ΔE(0)=1187.234(17)?MHz, which is 1/14 that for H(2)C=CH. The potential barrier height derived from the observed tunneling splitting by an analysis of the tunneling dynamics using a one-dimensional model is 1545?cm(-1), consistent with the value 1568?cm(-1) obtained for the normal vinyl. The observed spectrum was found to be perturbed by a hyperfine interaction connecting ortho and para levels. The constant for the interaction, which we call the ortho-para mixing Fermi contact interaction, has been determined to be δa(F) ((β))=68.06(53)?MHz. This is believed to be the first definite detection of such an interaction. By this interaction the ortho and para states of H(2)C=CD are mixed up to about 0.1%. The constant is more than 1000 times larger than spin-rotation interaction constants that cause ortho-para mixing in closed shell molecules and suggests extremely rapid conversion between the ortho and para nuclear spin isomers of H(2)C=CD. 相似文献
88.
Dr. Akihiro Ito Kazuhira Hata Kensuke Kawamoto Dr. Yasukazu Hirao Prof. Dr. Kazuyoshi Tanaka Dr. Motoo Shiro Dr. Ko Furukawa Prof. Dr. Tatsuhisa Kato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(35):10866-10878
para‐Phenylene‐bridged spirobi(triarylamine) dimer 2 , in which π conjugation through four redox‐active triarylamine subunits is partially segregated by the unique perpendicular conformation, was prepared and characterized by structural, electrochemical, and spectroscopic methods. Quantum chemical calculations (DFT and CASSCF) predicted that the frontier molecular orbitals of 2 are virtually fourfold degenerate, so that the oxidized states of 2 can give intriguing electronic and magnetic properties. In fact, the continuous‐wave ESR spectroscopy of radical cation 2 .+ showed that the unpaired electron was trapped in the inner two redox‐active dianisylamine subunits, and moreover was fully delocalized over them. Magnetic susceptibility measurements and pulsed ESR spectroscopy of the isolated salts of 2 , which can be prepared by treatment with SbCl5, revealed that the generated tetracation 2 4+ decomposed mainly into a mixture of 1) a decomposed tetra(radical cation) consisting of a tri(radical cation) moiety and a trianisylamine radical cation moiety (≈75 %) and 2) a diamagnetic quinoid dication in a tetraanisyl‐p‐phenylendiamine moiety and two trianisylamine radical cation moieties (≈25 %). Furthermore, the spin‐quartet state of the tri(radical cation) moiety in the decomposed tetra(radical cation) was found to be in the ground state lying 30 cal mol?1 below the competing spin‐doublet state. 相似文献
89.
The mechanism by which the ribosome catalyze peptide bond formation remains controversial. Here we describe the synthesis of dinucleotides that can be used in kinetic isotope effect experiments to assess the transition state of ribosome catalyzed peptide bond formation. These substrates are the isotopically labeled dinucleotide cytidylyl-(3′-5′)-3′-amino-3′-deoxy-3′-l-phenylalanyl-N6,N6-dimethyladenosine (Cm6ANPhe-NH2) and cytidylyl-(3′-5′)-3′-amino-3′-deoxy-3′-(l-2-hydroxy-3-phenylpropionyl)-N6,N6-dimethyladenosine (Cm6ANPhe-OH). These substrates are active in peptide bond formation and can be used to measure kinetic isotope effects in ribosome catalyzed protein synthesis. 相似文献
90.
Synthesis of gold nanoparticles modified with ionic liquid based on the imidazolium cation 总被引:6,自引:0,他引:6
The synthesis and processing of nanoparticles consisting of metallic nanocrystal cores and organic monolayer shells promise interesting technological applications. Here, we report the synthesis of gold nanoparticles modified with ionic liquids based on the imidazolium cation. Aggregation-induced color changes of the gold nanoparticles in an aqueous solution were used as an optical sensor for anions via anion exchange of ionic liquid moiety. We also demonstrated the phase transfer of the gold nanoparticles from aqueous media to ionic liquid. 相似文献