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941.
Dr. Tsukuru Minamiki Dr. Riku Kubota Yui Sasaki Koichiro Asano Prof. Tsuyoshi Minami 《ChemistryOpen》2020,9(5):573-581
Artificial receptor-based protein assays have various attractive features such as a long-term stability, a low-cost production process, and the ease of tuning the target specificity. However, such protein sensors are still immature compared with conventional immunoassays. To enhance the application potential of synthetic sensing materials, organic field-effect transistors (OFETs) are some of the suitable platforms for protein assays because of their solution processability, durability, and compact integration. Importantly, OFETs enable the electrical readout of the protein recognition phenomena of artificial receptors on sensing electrodes. Thus, we believe that OFETs functionalized with artificial protein receptors will be a powerful tool for the on-site analyses of target proteins. In this Minireview, we summarize the recent progress of the OFET-based protein assays including the rational design strategies for devices and sensing materials. 相似文献
942.
Palladium/Copper Dual Catalysis for the Cross‐Coupling of Aryl(trialkyl)silanes with Aryl Bromides 下载免费PDF全文
Takeshi Komiyama Dr. Yasunori Minami Yuki Furuya Prof. Dr. Tamejiro Hiyama 《Angewandte Chemie (International ed. in English)》2018,57(7):1987-1990
Whereas aryl(trialkyl)silanes are considered to be ideal organometallic reagents for cross‐coupling reactions owing to their stability, low toxicity, solubility, and easy accessibility, they are generally inert under typical cross‐coupling conditions. Disclosed herein is a palladium/copper catalytic system that enables the cross‐coupling of trimethyl, triethyl, tert‐butyldimethyl, and triisopropyl aryl silanes with aryl bromides. This process is applicable to the sequential C?H and C?Si bond arylation of thiophenes and the synthesis of poly(thiophene–fluorene)s. 相似文献
943.
Cyclic compounds have been consistently key components in organo functional molecules. To construct cycles, a catalytic two CH bond-cleaving annulation is one of the most ideal and straightforward methods with atom and step economies. Recently, many patterns of such annulation reactions have been developed, which construct a variety of cyclic compounds consisted of from simple to complex frameworks. This Digest focuses a recent progress in two or more than three CH bond-cleaving annulation reactions and is outlined as follows: (1) intramolecular annulation, (2) intermolecular annulation via double CH bond cleavages in one molecule, and (3) intermolecular annulation via double CH bond cleavages in two molecules. 相似文献
944.
The electronic structure of simple silicate and phosphate clusters, which are assumed to exist in rapidly quenched Li2O---SiO2 and Li2O---P2O5 glasses, has been calculated by the discrete variational (DV)-Xα molecular orbital method. The calculations have been carried out for several sizes of clusters, namely, tetrahedral units (SiO44− and PO43−), dimers (Si2O76− and P2O74−), and trimers (Si3O96− and P3O93−). For both systems the valence electronic state is characterized by an occupied valence band, with O 2p components, and an unoccupied band of Si or P orbitals, separated by an energy gap. The energy gap between the highest occupied molecular orbital (HOMO) and the loest unoccupied molecular orbital (LUMO) decreases with increasing cluster size. A mulliken population analysis show that the negative effective charge on the non-bridging oxygens is decreased with decreasing energy gap. The bond order of the Si---O and P---O bonds, and thus the strength of these bonds, is increased with increasing cluster size. 相似文献
945.
Zr---Al metallo-organic compounds (zircoaluminates), having (CH2)4COOH, (CH2)12CH3 and (CH2)2NH2 as the organofunctional groups, were treated preliminary by (1) spray-drying, (2) gelation of addition of 10% NH4OH aqueous solution followed by spray-drying and (3) rotary evaporation under a reduced pressure. After the treatment they were heated in air to prepare ZrO2---Al2O3 composite powders. The IR and DTA profiles for the treated compounds indicated that the procedures modified the structures for the zircoaluminates. The stability of tetragonal ZrO2 for the ZrO2---Al2O3 composite powder were dependent on the modification in the structure for the zircoaluminates. Balloon shaped particles, 0.5–2 μm in diameter, were obtained through procedure (1) and spherical particles, 1–4 μm in diameter, through (2). Tetragonal ZrO2 grains, 0.1–0.2 μm in diameter, were dispersed in the particles when heated at 1400°C. 相似文献
946.
T. R. Saito E. Kim D. Nakajima C. Rappold S. Bianchin O. Borodina V. Bozkurt M. Kavatsyuk Y. Ma F. Maas S. Minami B. Özel-Tashenov K. Yoshida 《Few-Body Systems》2013,54(7-10):1211-1214
The HypHI Phase 0 experiment with 6Li projectiles at 2 AGeV on a carbon target has been performed at GSI in order to demonstrate the feasibility of hypernuclear spectroscopy with induced reaction of heavy ion beams. Current data analyses have shown peaks in invariant mass distributions of p + π ? for Λ, 3He+ π ? for 3 Λ H and 4He + π ? for 4 Λ H. Lifetime values for the corresponding peaks have been also deduced, which are in good agreement with the former known values. 相似文献
947.
Sumikazu Ogata Hideyuki Tagaya Jun-Ichi Kadokawa Koji Chiba 《Molecular Crystals and Liquid Crystals》2013,570(2):419-424
Abstract A new preparation method of the fibrous organic-inorganic nanohybrids was established by the reaction of Zn(OH)2 with various organic carboxylic acids. Interlayer spacings of the reaction products of Zn(OH)2 with benzoic acid and p-phenyl azobenzoic acid were 1.46 and 2.04 nm, and these reaction products have layered structure. In IR spectra, new peaks of RCOO-Zn band appeared at around 1400 cm?1 and 1550 cm?1 indicating that hydroxyl groups reacted with organic carboxylic acids. SEM images of these reaction products showed fibrous morphology. The TEM image showed that the layer structure was constructed along the fiber direction. 相似文献
948.
Kazunori Kuwana Kozo Sekimoto Takeaki Minami Takahiro Tashiro Kozo Saito 《Proceedings of the Combustion Institute》2013,34(2):2625-2631
A fire whirl, observed during a wildland fire in Brazil in 2010, occurred over a narrow but long line fire and moved along the line fire at nearly a constant speed. There appeared to be no mountains, tall buildings or trees near the scene, indicating that the fire whirl was generated merely by the interaction between the line fire and background wind. Scale-model experiments having different line fire configurations were designed and performed to reconstruct the above-mentioned Brazil fire whirl. Moving fire whirls were successfully reconstructed during the scale-model experiments, the mechanism and conditions of which are discussed herein. 相似文献
949.
Norio Kashiwa Tomoaki Matsugi Shin-Ichi Kojoh Hideyuki Kaneko Nobuo Kawahara Shingo Matsuo Tadahito Nobori Jun-Ichi Imuta 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3657-3666
The control of hydroxylated polyethylene (PE) structures was investigated in the copolymerization of ethylene with allyl alcohol or 10-undecen-1-ol with a specific metallocene, methylaluminoxane, and trialkyl aluminum catalyst system through changes in the copolymerization conditions. The incorporation of allyl alcohol into the PE backbones was controllable through changes in the trialkyl aluminum, leading to terminally hydroxylated PE or a copolymer possessing hydroxyalkyl side chains. The copolymerization of ethylene with 10-undecen-1-ol gave copolymers with hydroxyalkyl side chains of various contents with a variety of molecular weights through changes in the copolymerization conditions. The obtained copolymers were useful as macroinitiators that allowed polar polymer segments to grow on the PE backbones, leading to the creation of graft copolymers that possessed PE and polar polymer segments. In this way, polyethylene-g-poly(propylene glycol) (PE-g-PPG) and polyethylene-g-poly(ϵ-caprolactone) (PE-g-PCL) were synthesized. The 13C NMR analysis of PE-g-PPG suggested that all the hydroxyl groups were consumed for propylene oxide polymerization, and transmission electron microscopy demonstrated nanoorder phase separation and indistinct phase boundaries. 13C NMR and gel permeation chromatography analyses indicated the formation of PE-g-PCL, in which 36–80 mol % of the hydroxyl groups worked as initiators for ϵ-caprolactone polymerization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3657–3666, 2003 相似文献
950.
Morphological studies of a hydrogen-bonded LC polymer obtained by photopolymerization in LC solvents 总被引:1,自引:0,他引:1
Hideyuki Kihara Toshiaki Miura Ryoichi Kishi Takashi Yoshida Mitsuhiro Shibata Ryutoku Yosomiya 《Liquid crystals》2003,30(7):799-809
Anisotropic morphologies and the phase behaviour of a hydrogen-bonded LC polymer obtained by photopolymerization in two kinds of LC solvent are discussed. The hydrogen-bonded LC monomer, 4-(6-acryloyloxyhexyloxy) benzoic acid (A6OBA), was photopolymerized in 4-cyano-4'-hexyloxybiphenyl (6OCB) and in 4-cyano-4'-undecyloxybiphenyl (11OCB), which show a nematic phase and a smectic A phase, respectively. After photo-polymerization, the LC media were removed by extraction and the pure polymer was observed by scanning electron microscopy. SEM images showed that the polymer possessed fibrous morphology with a fibre diameter of a few micrometers, based on polymerization-induced phase separation. The overall geometries reflected typical LC characteristics such as schlieren and focal-conic fan textures. It was found that the hydrogen bond between benzoic acid groups in the monomer was rigid enough to fix the anisotropic phase-separated structure forming during the early stage of phase separation; however, it could not permanently maintain the fibre structure due to dissociation at elevated temperature. X-ray measurements revealed that a well developed layer structure of the hydrogen-bonded mesogen existed in the polymer obtained from the smectic phase of 11OCB, whereas a polymer layer structure could develop only partially from the nematic phase of 6OCB. 相似文献