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951.
A sequential one‐pot synthesis of N‐sulfonylcyclothioureas from N‐monosulfonyl diamines, CS2 and chloroacetic acid at room temperature in water is described. In the absence of highly toxic thiophosgene and organic solvents, this method is environmentally benign. Simple reaction conditions, easy purification of the products, good yields and thioglycolic acid as the useful byproduct are also important attributes of this methodology. The plausible mechanism including tandem reactions is proposed. 相似文献
952.
M. Mouyane M. Womes J.C. Jumas J. Olivier-Fourcade P.E. Lippens 《Journal of solid state chemistry》2011,184(11):2877-2886
Calcium stannate (CaSnO3) and malayaite (CaSnSiO5) were synthesized by means of a high temperature solid-state reaction. Their crystal structures and morphologies were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy; their electrochemical properties were analyzed by galvanostatic tests. The amorphization of the initial electrode materials was followed by XRD. The first discharge of the oxides CaSnO3 and CaSnSiO5 shows a plateau at low potential, which is due to the progressive formation of Li–Ca–Sn and/or Li–Sn alloys as shown by 119Sn Mössbauer spectroscopy. The results reveal similar electrochemical mechanisms for CaSnO3 and CaSnSiO5 but they completely differ from those related to SnO2. 相似文献
953.
Dr. Xing Yuan Prof. Xiaojun Zhao Shuting Qiu Yizhuo Song 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(50):12807-12814
Phase engineering of the electrode materials in terms of designing heterostructures, introducing heteroatom and defects, improves great prospects in accelerating the charge storage kinetics during the repeated Li+/Na+ insertion/deintercalation. Herein, a new design of Li/Na-ion battery anodes through phase regulating is reported consisting of F-doped SnO2-SnS2 heterostructure nanocrystals with oxygen/sulfur vacancies (VO/VS) anchored on a 2D sulfur/nitrogen-doped reduced graphene oxide matrix (F-SnO2-x-SnS2-x@N/S-RGO). Consequently, the F-SnO2-x-SnS2-x@N/S-RGO anode demonstrates superb high reversible capacity and long-term cycling stability. Moreover, it exhibits excellent great rate capability with 589 mAh g−1 for Li+ and 296 mAh g−1 at 5 A g−1 for Na+. The enhanced Li/Na storage properties of the nanocomposites are not only attributed to the increase in conductivity caused by VO/VS and F doping (confirmed by DFT calculations) to accelerate their charge-transfer kinetics but also the increased interaction between F-SnO2-x-SnS2-x and Li/Na through heterostructure. Meanwhile, the hierarchical F-SnO2-x-SnS2-x@N/S-RGO network structure enables fast infiltration of electrolyte and improves electron/ion transportation in the electrode, and the corrosion resistance of F doping contributes to prolonged cycle stability. 相似文献
954.
Here, we propose a new strategy that employs a functional separator composed of radical scavenging agents for removal of radical species in the cell. In detail, a radical scavenger, trimesitylborane (TRMSB), is embedded on the surface of nano-sized tungsten oxide (WO3) by a simple one-step process and the resulting nanoparticles are coated onto conventional separators by a dip-coating process. Our screening test performed by chemical reaction of TRMSB with a radical indicator (2,2-diphenyl-1-picrylhydrazyl, DPPH) confirms that TRMSB effectively scavenges radical species via a chemical reaction, implying that the use of a WO3-TRMSB–functionalized separator would be effective for decreasing radical concentrations during electrochemical processes. In our electrochemical tests, the cell cycled with a WO3-TRMSB–functionalized separator exhibit showed both improved cycling retention compared to a cell cycled with a bare separator and improved physical and mechanical properties. 相似文献
955.
The challenging requirements of high safety, low-cost, all-climate and long lifespan restrict most battery technologies for grid-scale energy storage. Historically, owing to stable electrode reactions and robust battery chemistry, aqueous nickel–hydrogen gas (Ni–H2) batteries with outstanding durability and safety have been served in aerospace and satellite systems for over three decades ever since their first development in the 1970s. Despite their satisfactory performances, this technology has difficulty to be applied for grid-scale energy storage primarily because of their high cost resulting from the utilization of expensive platinum as anode hydrogen catalyst. In recent years, with the extensive exploration of inexpensive hydrogen evolution/oxidation reaction catalysts, advanced Ni–H2 batteries have been revived as promising battery chemistry for grid-scale energy storage applications. This mini-review provides an overview of the development activities of Ni–H2 batteries and highlights the recent advances in the application of advanced Ni–H2 batteries for grid-scale energy storage. New cost-effective hydrogen evolution/oxidation reactions catalysts, novel cathode materials, and advanced Ni–H2 battery designs toward further development of Ni–H2 batteries are discussed. The renaissance of advanced Ni–H2 battery technology is particularly attractive for future grid-scale energy storage applications. 相似文献
956.
Bing Li Tiankuo Wang Dr. Xin Wang Dr. Xin Wu Chenyu Wang Prof. Feng Miao Prof. Meng Qin Prof. Wei Wang Prof. Yi Cao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(34):7991-7997
Aqueous ultrasonic exfoliation by using proteins as dispersants allows for the simultaneous production and biofunctionalization of single- or few-layered 2D materials for biomedical applications. However, the production yield and quality are always a concern. Here, the production of stable, low-defect, and biofunctionalized 2D flakes of graphene by using bifunctional chimeric polyproteins as dispersants is shown. The chimeric polyproteins contain an amphiphilic protein, hydrophobin (HFBI), to serve as the anchoring point that strongly binds to graphene layers and tandem repeats of a globular protein, GB1, to respond and transmit the ultrasonic force for efficient mechanical exfoliation. For this reason, the production yield is much higher than those obtained by using HFBI alone. Moreover, the yield, lateral size and number of layers can be fine-tuned by the number of GB1 repeats. Other 2D materials, such as MoS2 and WS2, can also be exfoliated in the same manner, demonstrating the versatility of this approach. 相似文献
957.
958.
Federico Danzi Rui Martim Salgado Joana Espain Oliveira Albertino Arteiro Pedro Ponces Camanho Maria Helena Braga 《Molecules (Basel, Switzerland)》2021,26(8)
Structural power composites stand out as a possible solution to the demands of the modern transportation system of more efficient and eco-friendly vehicles. Recent studies demonstrated the possibility to realize these components endowing high-performance composites with electrochemical properties. The aim of this paper is to present a systematic review of the recent developments on this more and more sensitive topic. Two main technologies will be covered here: (1) the integration of commercially available lithium-ion batteries in composite structures, and (2) the fabrication of carbon fiber-based multifunctional materials. The latter will be deeply analyzed, describing how the fibers and the polymeric matrices can be synergistically combined with ionic salts and cathodic materials to manufacture monolithic structural batteries. The main challenges faced by these emerging research fields are also addressed. Among them, the maximum allowable curing cycle for the embedded configuration and the realization that highly conductive structural electrolytes for the monolithic solution are noteworthy. This work also shows an overview of the multiphysics material models developed for these studies and provides a clue for a possible alternative configuration based on solid-state electrolytes. 相似文献
959.
Yao-Yao Wang Wan-Yue Diao Dr. Chao-Ying Fan Prof. Xing-Long Wu Prof. Jing-Ping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(38):8975-8981
Lithium-ion batteries (LIBs) are one of the most significant energy storage devices applied in power supply facilities. However, a huge number of spent LIBs would bring harmful resource waste and environmental hazards. In this study, a benign hydrometallurgical method using phytic acid as precipitant is proposed to recover useful metallic Mn ions from spent LiMn2O4 batteries. Besides Mn-based cathodes, this recovery process is also applicable for other commercial batteries. More importantly, for the first time, the as-obtained manganous complex is employed as a nanofiller in a polyethylene oxide matrix to largely improve Li+ conductivity and transference number. As a result, when applied in all-solid-state lithium batteries, high capacity and outstanding cyclic stability are achieved with capacity retention of 86.4 % after 60 cycles at 0.1 C. The recovery of spent lithium batteries not only has benefits for the environment and resources, but also shows great potential application in all-solid-state lithium batteries, which opens up a costless and efficient circulation pathway for clean and reliable energy storage systems. 相似文献
960.
Qian Li Mingqi Xu Tong Wang Haijun Wang Prof. Jingwen Sun Prof. Jingquan Sha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(20):e202200207
To address the poor cycling stability and low rate capability of MoS2 as electrode materials for lithium-ion batteries (LIBs), herein, the CoS2/MoS2/PDDA-rGO/PMo12 nanocomposites are constructed via a simple hydrothermal process, combining the advantages of all three, namely, CoS2/MoS2 heterojunction and polyoxometalates (POMs) provide abundant catalytically active sites and increase the multi-electron transfer ability, and the positively charged poly(diallyldimethylammonium chloride) modified reduced graphene oxide (PDDA-rGO) improve electronic conductivity and effectively prevent the aggregation of MoS2, meanwhile stabilize the negatively charged [PMo12O40]3−. After the electrochemical testing, the resulting CoS2/MoS2/PDDA-rGO/PMo12 nanocomposite achieved 1055 mA h g−1 initial specific capacities and stabilized at 740 mA h g−1 after 150 cycles at 100 mA g−1 current density. And the specific capacities of MoS2, MoS2/PDDA-rGO, CoS2/MoS2, and CoS2/MoS2/PDDA-rGO were 201, 421, 518, and 589 at 100 mA g−1 after 150 cycles, respectively. The fact of the greatly improving capacity of MoS2-based nanocomposites suggests its potential for high performance electrode materials of LIBs. Moreover, the lithium storage mechanism of CoS2/MoS2/PDDA-rGO/PMo12 has been discussed on the basis of cyclic voltammetry with different scan rates. 相似文献