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171.
172.
Abstract Polarographic reduction and electrolytically initiated anionic polymerization of various monomers have been investigated with tetra-n-butylammonium perchlorate in dimethoxyethane. 相似文献
173.
The reactions of some diorganonickel(II) complexes with N-bromosuccinimide (NBS) resulted in facile bromine for hydrogen substitution in aromatic, alkynyl or alkenyl substituents, or in the addition of NBS to CC bonds. 相似文献
174.
Ilhyong Ryu Membo Ryang Ilsong Rhee Haruo Omura Shinji Murai Noboru Sonoda 《合成通讯》2013,43(12):1175-1179
An improved and convenient procedure for symmetrical aliphatic ketone synthesis is described, which employs the reaction of alkylmercuric bromides with nickel carbonyl in the presence of potassium iodide. 相似文献
175.
Yann Molard Dr. Frederick Dorson Konstantin A. Brylev Dr. Michael A. Shestopalov Yann Le Gal Stéphane Cordier Dr. Yuri V. Mironov Dr. Noboru Kitamura Prof. Christiane Perrin Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(19):5613-5619
The embedding of functional inorganic entities into polymer matrices has become an intense field of investigation in which the main challenges are to keep the added value of the inorganic entities while preventing their self‐aggregation within the organic matrix. We present a simple way to obtain a homogeneous highly red‐NIR luminescent hybrid copolymer that contains covalently bonded nanometric‐sized {Re6} octahedral clusters. The [Re6Sei8(OH)a6]4? cluster complexes are primarily functionalized in two steps with tert‐butylpyridine (TBP) and methacrylic acid (MAC) to give neutral [Re6Se8(TBP)4(MAC)2] building blocks that are copolymerized with methyl methacrylate (MMA) either in solution or in bulk in the presence of azobisisobutyronitrile as an initiator. Several samples containing 0, 0.025, 0.05, and 0.1 wt % of functionalized {Re6} clusters were prepared. As the {Re6} cluster/MMA ratio is very low, the obtained copolymers keep the entire processability of pure poly(methyl methacrylate) (PMMA), as demonstrated by differential scanning calorimetry and thermogravimetric analysis. Voltammetric and luminescence studies also indicate that the intrinsic properties of the clusters are preserved within the polymer matrix. All the samples show a bright (emission quantum yield=0.07), broad, and structureless emission band, which extends from λ=600 nm to more than λ=950 nm, with the maximum wavelength centered around λem=710 nm either in solution or in the solid state. Moreover, the high stability of the incorporated inorganic phosphors prevents the material from photobleaching, and thus the luminescence properties are kept entirely even after nine months of ageing. 相似文献
176.
Yabushita A Kanda D Kawanaka N Kawasaki M Ashfold MN 《The Journal of chemical physics》2006,125(13):133406
The photodissociation dynamics of amorphous solid water (ASW) films and polycrystalline ice (PCI) films at a substrate temperature of 100 K have been investigated by analyzing the time-of-flight (TOF) mass spectra of photofragment hydrogen atoms at 157 and 193 nm. For PCI films, the TOF spectrum recorded at 157 nm could be characterized by a combination of three different (fast, medium, and slow) Maxwell-Boltzmann energy distributions, while that measured at 193 nm can be fitted in terms of solely a fast component. For ASW films, the TOF spectra measured at 157 and 193 nm were both dominated by the slow component, indicating that the photofragment H atoms are accommodated to the substrate temperature by collisions. H atom formation at 193 nm is attributed to the photodissociation of water species on the ice surface, while at 157 nm it is ascribable to a mixture of surface and bulk photodissociations. Atmospheric implications in the high latitude mesopause region of the Earth are discussed. 相似文献
177.
Tetsuya Kida Atsunori Yamasaki Noboru Yamazoe 《Journal of solid state chemistry》2010,183(10):2426-2431
We carried out the partial substitution of the B-site in BaFeO3−δ perovskite with divalent cations to develop novel oxygen-permeable materials. We demonstrated that the partial substitution of Cu or Ni by more than 10% resulted in the stabilization of the cubic perovskite structure even at room temperature in a highly oxygen-permeable phase, as revealed by the X-ray diffraction (XRD) analysis. The Cu substitution was more effective for the stabilization, because the introduction of Cu in the lattice more effectively made the Goldschmidt tolerance factor (t) close to 1.0. Ni- and Cu-substituted BaFeO3−δ membranes showed higher oxygen permeabilities than their parent BaFeO3−δ membranes particularly at lower temperatures around 600-700 °C owing to the stabilization of the cubic phase. Among the fabricated membranes, a BaFe0.85Cu0.15O3−δ membrane (1.0 mm thickness) showed the highest oxygen permeation flux (1.8 cm3 min−1 cm−2 at 930 °C) under an air/He gradient. The results indicated that Cu-substituted BaFeO3-δ is promising as a material for Co-free membranes with high oxygen permeabilities. 相似文献
178.
Noboru Mataga Yoshikane Kawasaki Yoshikazu Torihashi 《Theoretical chemistry accounts》1964,2(2):168-176
The results of systematic experimental studies on the hydrogen bonding and proton transfer reactions between excited naphthol molecule and aliphatic amine molecule in nonhydroxylic solvents are described and interpreted.The mechanism of the proton transfer process is discussed on the basis of the - interaction in the hydroxy group of naphthol and the charge transfer interaction between the proton acceptor and the donor in the excited electronic state.
Zusammenfassung Die Ergebnisse systematischer experimenteller Untersuchungen über Wasserstoffbrückenbindung und Protonenaustausch zwischen angeregten Naphtholmolekülen und aliphatischen Aminen werden beschrieben und interpretiert. Es werden Lösungsmittel ohne Hydroxylgruppen benutzt.Der Mechanismus der Protonenaustauschreaktion wird diskutiert auf der Basis einer --Wechselwirkung in der Hydroxylgruppe des Naphtholmoleküls und einer charge-transfer-Wechselwirkung zwischen Protonen-Akzeptor und -Donor. Dabei befindet sich der Donor in einem angeregten Elektronenzustand.
Résumé Les résultats d'études systématiques expérimentales sur la liaison hydrogène et les réactions de transfert de proton entre des molécules de naphtol excitées et des amines aliphatiques sont décrits et interprétés. Des solvants non-hydroxyliques sont employés.Le mécanisme du transfert de proton est discuté sur base d'une interréaction - dans la groupe hydroxyle du naphtol et d'un transfert de charge entre l'accepteur et le donneur du proton, le donneur étant en état excité.相似文献
179.
180.
The picosecond time-resolved absorption spectra of water and some alcohols were measured by means of 266 nm multiphoton photolysis. The formation time 相似文献