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971.
In this work we calculate the mass spectrum of strangeonium up to the 3D multiplet within a nonrelativistic linear potential quark model.Furthermore,using the obtained wave functions,we also evaluate the strong decays of the strangeonium states with the ^3P_0 model.Based on our successful explanations of the well established states φ(1020) , φ(1680) , h_1(1415) , f'_2(1525) ,and φ_3(1850) ,we further discuss the possible assignments of strangeonium-like states from experiments by combining our theoretical results with observations.It is found that some resonances,such as f_2(2010) and f_2(2150) ,listed by the Particle Data Group,and X(2062) and X(2500) ,newly observed by BESIII,may be interpreted as strangeonium states.The possibility of φ(2170) as a candidate for φ(3S) or φ(2D) cannot be excluded.We expect our results to provide useful references for looking for the missing s\bar{s} states in future experiments. 相似文献
972.
Haipeng Wang Liang Hu Wenjun Xie Jian Chang Chenhui Zheng Mingxing Li Qing Wang Hui Liao Dingnan Liu Bingbo Wei 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(15):e202400312
The metastable liquid properties and chemical bonds beyond 2000 K remain a huge challenge for ground-based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb−Si and Zr−V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338 K exhibited an extreme undercooling of 437 K, approaching the 0.2TE threshold for homogeneous nucleation of liquid-solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid-solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances. 相似文献
973.
974.
975.
MXenes,a new family of functional two-dimensional(2 D) materials,have shown great potential for an extensive variety of applications within the last decade.Atomic defects and functional groups in MXenes are known to have a tremendous influence on the functional properties.In this review,we focus on recent progress in the characterization of atomic defects and functional group chemistry in MXenes,and how to control them to directly influence various properties(e.g.,electron transport,Li+ adsorption,hydrogen evolution reaction(HER) activity,and magnetism) of 2 D MXenes materials.Dynamic structural transformations such as oxidation and growth induced by atomic defects in MXenes are also discussed.The review thus provides perspectives on property optimization through atomic defect engineering,and bottom-up synthesis methods based on defect-assisted homoepitaxial growth of MXenes. 相似文献
976.
Jiqian Liu Lijuan Han Wenzheng Han Linsheng Gui Zhenzhen Yuan Shengzhen Hou Zhiyou Wang Baochun Yang Sayed Haidar Abbas Raza Abdulaziz Faisal Saleh Alowais Alaa Ahmed Alraddadi Anwar Mohammed Alanazi 《Molecules (Basel, Switzerland)》2023,28(1)
There are limited reports about the effect of different heat treatments on the quality and flavor of Black Tibetan sheep meat. The current study examined the effect of pan-frying, deep-frying, baking, and boiling treatment on the quality of Black Tibetan sheep meat; the amino acid, fatty acid, and volatile flavor compounds (VFCs) were investigated by a texture analyzer, ultra-high-performance liquid chromatography (UHPLC), gas chromatography (GC), and headspace-gas chromatography-ion mobility (HS-GC-IMS). The key VFCs were identified through orthogonal partial least squares discrimination analysis (OPLS-DA), and variable importance projection (VIP) values. In addition, Pearson’s correlations between meat quality parameters and key VFCs were examined. The sensory scores, including texture, color, and appearance, of baked and pan-fried meat were higher than those of deep-fried and boiled meat. The protein (40.47%) and amino acid (62.93 µmol/g) contents were the highest in pan-fried meat (p < 0.05). Additionally, it contained the highest amounts of monounsaturated and polyunsaturated fatty acids, such as oleic, linoleic, and α-linolenic acids (p < 0.05). Meanwhile, pan-fried and deep-fried meat had higher amounts of VFCs than baked meat. The OPLS-DA similarity and fingerprinting analyses revealed significant differences between the three heat treatment methods. Aldehydes were the key aroma compounds in pan-fried meat. Importantly, 3-methylbutyraldehyde and 2-heptanone contents were positively correlated with eicosenoic, oleic, isooleic, linoleic, α-Linolenic, and eicosadiene acids (p < 0.05). To sum up, pan-fried Black Tibetan sheep meat had the best edible, nutritional, and flavor quality. 相似文献
977.
W波段扩展互作用速调管电子光学系统由皮尔斯电子枪与均匀永磁聚焦系统组成,用于电子注的产生与传输。利用Vaughan迭代综合法及数值模拟优化设计了皮尔斯电子枪,并按照电子注传输特性要求研制了均匀永磁聚焦结构。根据电子光学系统的三维模拟,导流系数0.21 P,注电流大于0.5 A,注平均半径小于0.3 mm,射程大于11 mm。永磁聚焦磁场约0.33 T,传输距离大于50 mm,电子注通过率达到100%。电子枪与聚焦系统已加工完毕并通过测试,技术指标满足要求。 相似文献
978.
Dr. Huilin Zhang Dr. Yang Chen Dr. Wei Hua Wenjun Gu Dr. Hongjun Zhuang Dr. Huiyan Li Dr. Xingwu Jiang Prof. Ying Mao Prof. Yanyan Liu Prof. Dayong Jin Prof. Wenbo Bu 《Angewandte Chemie (International ed. in English)》2023,62(15):e202300356
Sustained signal activation by hydroxyl radicals (⋅OH) has great significance, especially for tumor treatment, but remains challenging. Here, a built-in electric field (BIEF)-driven strategy was proposed for sustainable generation of ⋅OH, thereby achieving long-lasting chemodynamic therapy (LCDT). As a proof of concept, a novel Janus-like Fe@Fe3O4−Cu2O heterogeneous catalyst was designed and synthesized, in which the BIEF induced the transfer of electrons in the Fe core to the surface, reducing ≡Cu2+ to ≡Cu+, thus achieving continuous Fenton-like reactions and ⋅OH release for over 18 h, which is approximately 12 times longer than that of Fe3O4−Cu2O and 72 times longer than that of Cu2O nanoparticles. In vitro and in vivo antitumor results indicated that sustained ⋅OH levels led to persistent extracellular regulated protein kinases (ERK) signal activation and irreparable oxidative damage to tumor cells, which promoted irreversible tumor apoptosis. Importantly, this strategy provides ideas for developing long-acting nanoplatforms for various applications. 相似文献
979.
Jiayi Chen Dr. Dashuai Wang Xiaoxuan Yang Wenjun Cui Prof. Dr. Xiahan Sang Zilin Zhao Dr. Liguang Wang Dr. Zhongjian Li Dr. Bin Yang Prof. Dr. Lecheng Lei Prof. Dr. Jinyang Zheng Prof. Dr. Liming Dai Prof. Dr. Yang Hou 《Angewandte Chemie (International ed. in English)》2023,62(10):e202215406
Cu-based catalysts have been widely applied in electroreduction of carbon dioxide (CO2ER) to produce multicarbon (C2+) feedstocks (e.g., C2H4). However, the high energy barriers for CO2 activation on the Cu surface is a challenge for a high catalytic efficiency and product selectivity. Herein, we developed an in situ *CO generation and spillover strategy by engineering single Ni atoms on a pyridinic N-enriched carbon support with a sodalite (SOD) topology (Ni-SOD/NC) that acted as a donor to feed adjacent Cu nanoparticles (NPs) with *CO intermediate. As a result, a high C2H4 selectivity of 62.5 % and an industrial-level current density of 160 mA cm−2 at a low potential of −0.72 V were achieved. Our studies revealed that the isolated NiN3 active sites with adjacent pyridinic N species facilitated the *CO desorption and the massive *CO intermediate released from Ni-SOD/NC then overflowed to Cu NPs surface to enrich the *CO coverage for improving the selectivity of CO2ER to C2H4. 相似文献
980.
Dr. Xiao‐Na Li Dr. Xiao‐Nan Wu Dr. Xun‐Lei Ding Bo Xu Prof. Dr. Sheng‐Gui He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(35):10998-11006
Vanadium–silver bimetallic oxide cluster ions (VxAgyOz+; x=1–4, y=1–4, z=3–11) are produced by laser ablation and reacted with ethane in a fast‐flow reactor. A reflectron time of flight (Re‐TOF) mass spectrometer is used to detect the cluster distribution before and after the reactions. Hydrogen atom abstraction (HAA) reactions are identified over VAgO3+, V2Ag2O6+, V2Ag4O7+, V3AgO8+, V3Ag3O9+, and V4Ag2O11+ ions, in which the oxygen‐centered radicals terminally bonded on V atoms are active sites for the facile HAA reactions. DFT calculations are performed to study the structures, bonding, and reactivity. The reaction mechanisms of V2Ag2O6++C2H6 are also given. The doped Ag atoms with a valence state of +1 are highly dispersed at the periphery of the VxAgyOz+ cluster ions. The reactivity can be well‐tuned gradually by controlling the number of Ag atoms. The steric protection due to the peripherally bonded Ag atoms greatly enhances the selectivity of the V–Ag bimetallic oxide clusters with respect to the corresponding pure vanadium oxide systems. 相似文献