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961.
Yousefzadeh Shahrouz Rajabi Hamid Ghajari Navid Sarafraz Mohammad Mohsen Akbari Omid Ali Goodarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2779-2803
Journal of Thermal Analysis and Calorimetry - The main purpose of this research is the numerical modeling of laminar mixed convection heat transfer inside an open square cavity with different heat... 相似文献
962.
Wenli Zhang Zhen Cao Wenxi Wang Eman Alhajji Abdul‐Hamid Emwas Pedro M. F. J. Costa Luigi Cavallo Husam N. Alshareef 《Angewandte Chemie (International ed. in English)》2020,59(11):4448-4455
The limited potassium‐ion intercalation capacity of graphite hampers development of potassium‐ion batteries (PIB). Edge‐nitrogen doping is an effective approach to enhance K‐ion storage in carbonaceous materials. One shortcoming is the lack of precise control over producing the edge‐nitrogen configuration. Here, a molecular‐scale copolymer pyrolysis strategy is used to precisely control edge‐nitrogen doping in carbonaceous materials. This process results in defect‐rich, edge‐nitrogen doped carbons (ENDC) with a high nitrogen‐doping level (up to 10.5 at %) and a high edge‐nitrogen ratio (87.6 %). The optimized ENDC exhibits a high reversible capacity of 423 mAh g?1, a high initial Coulombic efficiency of 65 %, superior rate capability, and long cycle life (93.8 % retention after three months). This strategy can be extended to design other edge‐heteroatom‐rich carbons through pyrolysis of copolymers for efficient storage of various mobile ions. 相似文献
963.
Khaleghi Abbasabadi Masoud Khodabakhshi Saeed Esmaili Zand Hamid Reza Rashidi Alimorad Gholami Pooya Sherafati Zahra 《Research on Chemical Intermediates》2020,46(10):4447-4463
Research on Chemical Intermediates - In the present research, piperazine grafted-reduced graphene oxide RGO-N-(piperazine) was synthesized through a three-step reaction and employed as a highly... 相似文献
964.
Ahmad Reza Oliaey Asadollah Boshra Sharifah Bee Abdul Hamid 《Heteroatom Chemistry》2015,26(2):150-160
We modeled and studied three types of novel B12C24N12 cages. The structure of these cages was inspired by those of BC2N nanotubes and the B24N24 fulborene skeleton. Density functional theory was used to investigate the various properties of the cages. All three isomers of B12C24N12 were vibrationally stable. The highest occupied molecular orbital‐lowest unoccupied molecular orbital band gap was dependent on the BC2N cage type. The B12C24N12‐II cage was the most favorable nanocage and exhibited a large electric dipole moment. Natural bonding orbital (NBO) analysis confirmed the existence of lone pairs and unoccupied orbitals in the B12C24N12 cages. New donor–acceptor interactions of natural MOs (Molecular Orbitals) were observed in BC2N nanocages. The NBO and atomic polar tensor charges appeared to be fairly well correlated, showing that atomic charges can be obtained at a lower computational cost in this way. 相似文献
965.
Ali Souldozi Seyed Hamid Reza Shojaei Ali Ramazani Katarzyna lepokura Tadeusz Lis 《结构化学》2013,32(1):82-88
The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573(3), b = 19.533(7), c = 9.876(3), β = 92.35(4)°, V = 1845.2(10)3, T = 85(2) K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections withI>2σ(I). 相似文献
966.
Mahmood Tajbaksh Maryam Farhang Hamid Reza Mardani Rahman Hosseinzadeh Yaghoub Sarrafi 《催化学报》2013,34(12):2217-2222
A one pot three‐component coupling reaction of phenylacetylene, aldehyde, and amine derivatives in the presence of Cu(II) Salen complex as an efficient heterogeneous catalyst under solvent‐free conditions is reported. The catalyst displayed high activity and afforded the corresponding propargylamines in good to excellent yields. This method provides a wide range of substrate applicability. The catalyst was reused several times without significant loss of its catalytic activity. 相似文献
967.
The UV–Vis spectra for 1:2 complexation of four different para‐substituted meso‐tetraphenylporphyrin (H2t(4‐X)pp) and meso‐tetraphenylporphyrins (H2tpp) with trimethylsilyl chloride (TMSC) displayed large and different redshifts (28–32.4 nm) of Soret and (15–41.7 nm) Q(0‐0) bands, whereas 1:2 complexation of the less flexible tetramesitylporphyrin (H2tmp) with TMSC led to rather small redshift (24.8 nm) of the Soret band and blueshift (−7.4 nm) of the Q(0‐0) band. The varying spectral behavior for the porphyrins complexation seems to essentially reflect the different extent of π‐interactions between the meso‐aryl groups and the presumably saddled porphyrin macrocycle, through their relative coplanarity. The observed order of the rate constants for the complexation of various para‐substituted porphyrins, H2t(4‐OCH3)pp (9.27 ± 0.03) × 10−3 > H2t(4‐CH3)pp (6.68 ± 0.05) × 10−3 > H2tpp (3.2 ± 0.05) × 10−3 > H2t(4‐Cl)pp (8.36 ± 0.06) × 10−4, clearly demonstrated a higher reaction rate for the porphyrins containing para‐substituents with stronger electron donor ability. The calculated order for porphyrins (0.9 ± 0.1) and for TMSC (1.0 ± 0.1) suggests rate = K[Por][TMSC] for the complexation. Attempts were made to explain the absence of spectral evidence for the presence of an intermediate 1:1 (TMSC) Por adduct in terms of its high reactivity and/or relative instability. © 2007 Wiley Periodicals, Inc. 39: 231–235, 2007 相似文献
968.
基于3S的塔里木河中游景观格局变化特征分析 总被引:1,自引:0,他引:1
景观格局变化研究,是目前景观生态学的研究热点.本文把生态环境脆弱与人类活动的影响比较强烈的塔里木河中游选为研究靶区,利用遥感的手段获取试验区1973、1992和2000年景观格局的基础数据,在3S技术和景观生态学方法支持下,对塔里木河中游近30年土地利用和景观结构的时空变化特征进行了研究,对该地区的开发利用和生态环境保护提供科学依据. 相似文献
969.
970.