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121.
Inside Cover: Uniaxial Movements of a Metal–Cyanide Framework Switched by Weak Interactions through Dehydration and Rehydration (Chem. Eur. J. 27/2014)
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122.
The First Five‐Membered‐Heterocycle‐Fused Subphthalocyanine Analogues: Chiral Tri(benzo[b]thiopheno)subporphyrazines
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Hong Shang Luyang Zhao Dr. Dongdong Qi Chao Chen Prof. Dr. Jianzhuang Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16266-16272
Two tri(benzo[b]thiopheno)subporphyrazine regioisomers with C3 and C1 molecular symmetry have been isolated from the cyclotrimerization of benzo[b]thiophene‐2,3‐dicarbonitrile as the first five‐membered‐heterocycle‐fused subphthalocyanine analogues. Optical resolution of both regioisomers was achieved by using a chiral HPLC technique, affording the first chiral subphthalocyanine analogues. 相似文献
123.
Chemical and Toxicological Investigations of a Previously Unknown Poisonous European Mushroom Tricholoma terreum
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Xia Yin Dr. Tao Feng Prof. Jian‐Hua Shang Yun‐Li Zhao Fang Wang Zheng‐Hui Li Ze‐Jun Dong Prof. Dr. Xiao‐Dong Luo Prof. Dr. Ji‐Kai Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):7001-7009
The established tradition of consuming and marketing wild mushrooms has focused attention on mycotoxicity, which has become a global issue. In the present study, we describe the toxins found in a previously unknown poisonous European mushroom Tricholoma terreum. Fifteen new triterpenoids terreolides A–F ( 1 – 6 ) and saponaceolides H–P ( 8 – 16 ) were isolated from the fruiting bodies of the toxic mushroom T. terreum. Terreolides A–C ( 1 – 3 ) possessed a unique 5/6/7 trioxaspiroketal system, whereas terreolides D–F ( 4 – 6 ) possessed an unprecedented carbon skeleton. Two abundant compounds in the mushroom, saponaceolide B ( 7 ) and saponaceolide M ( 13 ), displayed acute toxicity, with LD50 values of 88.3 and 63.7 mg kg?1 when administered orally in mice. Both compounds were found to increase serum creatine kinase levels in mice, indicating that T. terreum may be the cause of mushroom poisoning ultimately leading to rhabdomyolysis. 相似文献
124.
Exceedingly Fast Copper(II)‐Promoted ortho CH Trifluoromethylation of Arenes using TMSCF3
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Ming Shang Shang‐Zheng Sun Dr. Hong‐Li Wang Dr. Brian N. Laforteza Prof. Dr. Hui‐Xiong Dai Prof. Dr. Jin‐Quan Yu 《Angewandte Chemie (International ed. in English)》2014,53(39):10439-10442
The direct ortho‐trifluoromethylation of arenes, including heteroarenes, with TMSCF3 has been accomplished by a copper(II)‐promoted C? H activation reaction which completes within 30 minutes. Mechanistic investigations are consistent with the involvement of C? H activation, rather than a simple electrophilic aromatic substitution (SEAr), as the key step. 相似文献
125.
The Divergent Synthesis of Nitrogen Heterocycles by Rhodium(II)‐Catalyzed Cycloadditions of 1‐Sulfonyl 1,2,3‐Triazoles with 1,3‐Dienes
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Dr. Hai Shang Yuanhao Wang Dr. Yu Tian Juan Feng Prof. Dr. Yefeng Tang 《Angewandte Chemie (International ed. in English)》2014,53(22):5662-5666
The first rhodium(II)‐catalyzed aza‐[4+3] cycloadditions of 1‐sulfonyl 1,2,3‐triazoles with 1,3‐dienes have been developed, and enable the efficient synthesis of highly functionalized 2,5‐dihydroazepines from readily available precursors. In some cases, the reaction pathway could divert to formal aza‐[3+2] cycloadditions, thus leading to 2,3‐dihydropyrroles. In this context, the titled reaction represents a capable tool for the divergent synthesis of two types of synthetically valuable aza‐heterocycles from common rhodium(II) iminocarbene intermediates. 相似文献
126.
Yingrui Shang Jing Zhao Jingqing Li Zhonghua Wu Shichun Jiang 《Colloid and polymer science》2014,292(12):3205-3221
The influence of annealing on the microstructure and mechanical properties of β-form isotactic polypropylene (iPP) was investigated via in situ synchrotron small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC). Transition of β-iPP to α-iPP was investigated via recrystallization at high annealing temperatures (T a?>?120 °C). And crystallinity, crystal sizes, and long period of ordered structure increased with increasing annealing temperature. Abrupt changes were found in both mechanical properties and structural features at the same T a range (~120 °C). The in situ synchrotron SAXS and WAXD shows that the destruction of b phase at yielding and after yielding should account for the ductility of β-iPP. The thermodynamics and kinetics of annealing were investigated with DSC and X-ray synchrotron experiments. A characteristic annealing time was investigated, which measures the rate of phase evolution in annealing of β-iPP. Eventually, a hypothesized model can be used to describe the property/structure relations during this process. 相似文献
127.
超级电容器具有功率密度高、充放电速度快、循环寿命长和维护成本低的特点,在电动车动力电池领域具有潜在的应用前景。超级电容器性能主要由其电极材料所决定。聚苯胺易合成、理论比容量高,而且导电性能优异,作为超级电容器电极材料有很高的应用价值。但是,在长期使用过程中,它的体积容易发生膨胀或收缩,循环寿命差。为了解决这个问题,将聚苯胺与石墨烯复合可以扬长避短,充分利用两者之间的协同效应,赋予复合材料优异电化学电容性能。本文综述了超级电容器用石墨烯-聚苯胺复合材料的制备方法,包括原位聚合法、油水界面合成法、电化学合成法、层层自组装法等;提出了三维网状石墨烯和对石墨烯-聚苯胺复合材料进行改性来提高复合材料的电化学电容性能的思路。 相似文献
128.
建立了测定白酒中6种邻苯二甲酸酯类增塑剂的真空离心浓缩/气相色谱-质谱联用(GC-MS)分析方法。样品经真空离心浓缩,正己烷提取,取上层正己烷,4000r/min离心5min,采用GC-MS测定,外标法定量。在0.10~5.00μg/mL范围内,相关系数r20.992,样品在0.10~2.00 mg/kg范围内加标,平均回收率在88.83%~111.67%之间,相对标准偏差(RSD)为4.85%~11.35%,检出限(LOD)在0.02~0.05 mg/kg之间。采用该方法对16个白酒样品进行测定,结果表明该法简便、快速、结果准确可靠、灵敏度高,能够满足白酒中6种邻苯二甲酸酯增塑剂检测需求。 相似文献
129.
Inorganic-organic or hybrid perovskite materials, which are the complementary counterparts of pure inorganic perovskites, can provide many new opportunities in the researches of phase transitions, critical phenomena, and relevant properties, as they combine the characteristics of inorganic and organic components. Therefore, the hybrid perovskites of ammonium metal formate framework are very promising, and their properties have been found to be strongly dependent on the characteristics of the constituent metal ions and/or ammonium ions. Herein, we used solid solution strategies, borrowed from solid state chemistry, to investigate the anisotropic diluted magnetic hybrid perovskite system of [CH3NH3][CoxZn1-x(HCOO)3], wherein the B-sites are occupied by the mixed metal ions of Co2+ and Zn2+. The solid solution compounds of this series in the range x = 0–1 (or the molar percent Co% = 0–100%) were successfully prepared using conventional solution chemistry methods. The resulting compounds were demonstrated to be iso-structural by using both single-crystal and powder X-ray diffraction analyses. The solid solution crystals belong to the orthorhombic space group Pnma, with the cell parameters being a = 8.3015(2)–8.3207(3) Å, b = 11.6574(4)–11.6811(5) Å, c = 8.1315(3)–8.1427(4) Å, and V = 787.89(5)–790.98(7) Å3. The perovskite structure consists of a simple cubic anionic metal-formate framework and CH3NH3+ cations which are located in the framework cavities, with N―H···O hydrogen bonds formed between the framework and the cation. The members of this series showed negligible changes (< 0.4%) in their respective lattice and structural parameters. Thus, the prepared solid solution compounds constitute good molecule-based examples for the study of magnetic dilution under almost the same structural parameters and molecular geometries. Upon dilution, the magnetization per mole of Co at low temperatures and low fields was suppressed by the magnetic anisotropy of Co2+ and gradual destruction of the large spin canting between coupled Co2+ ions, in contrast to the magnetization enhancement observed in the isotropic diluted system of [CH3NH3][MnxZn1-x(HCOO)3] with the same perovskite structure. The percolation limit was estimated as (Co%)P = 27(1)% (or xP = 0.27(1)) from the magnetic data, which was slightly lower than that predicted by the percolation theory for a simple cubic lattice (31%); this trend was due to the strong magnetic anisotropy of the present system. In addition, rare incommensurate phase transitions were primarily detected below ~120 K for the pure Co and Zn members, which may also affect the magnetic properties of the materials. 相似文献
130.
The synchronization of diagnosis and treatment is a new trend in cancer treatment. Photoacoustic imaging (PAI) and photothermal therapy (PTT) are recognized as one of the perfect combinations. The autocatalytic polymerization of selenium/polypyrrole (Se@PPy) nanocomposites with a wide-absorption band at near-infrared region (NIR, 800 nm) has been developed in this paper. The wide optical absorption characteristics enable Se@PPy nanocomposites to achieve multi-spectral PAI. Ex vivo experiments show desirable photoacoustic ability of the Se@PPy nanocomposites at wavelengths ranging from 700 nm to 900 nm, which is better than that of commercial indocyanine green (ICG). Se@PPy nanocomposites have high photothermal conversion efficiency up to 36.3% as well as excellent photo-thermal stability. In vitro cytotoxicity test demonstrates that the Se@PPy nanocomposites have good bio-safety. Furthermore, the feasibility of Se@PPy nanocomposites for enhancing multi-spectral PAI guided PTT was verified on 4T1 tumor-bearing nude mice. Our results indicate that Se@PPy nanocomposites could be used as an effective theranostic agent for near-infrared light-mediated PAI and PTT of tumor. 相似文献