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61.
Yanru Shen Yongqi Tong Yuhao Zhao Lin Zhang Shi Bu Weigang Xu Chenye Pan Hong Ding Zhengjun Yang 《Advanced Powder Technology》2021,32(6):1858-1868
Aiming at the problems of low collection efficiency of fine particulate matter and large area occupied by existing electrostatic precipitators (ESP), a new type of horizontal electrode ESP is proposed. It has the advantages of accelerating turbulent coalescence, increasing the effective dust collecting area and increasing the particle driving speed. The performance of the new type of ESP is systematic studied through simulation and experiment at the same time, and the results matches well. By comparing the dust removal effect of the horizontal electrode ESP and the conventional ESP, it can be concluded that the horizontal electrode ESP has a better dust removal efficiency, and can still maintain a better dust removal effect under high air velocity. The dust removal efficiency of new ESP can reach above 98% under the experimental conditions. 相似文献
62.
Zhengyuan Zhang Yuqi Xu Meng Wu Bifu Luo Jinhui Hao Weidong Shi 《International Journal of Hydrogen Energy》2021,46(21):11652-11663
Rational design of highly conductive and hydrophilic electrocatalysts are extremely important to promote their oxygen evolution reaction (OER). In this work, a homogeneously dispersed carbon-based cobalt/iron catalyst (Co/Fe–C) with abundant oxygen vacancies and favorable hydrophilicity is fabricated via a facile metal-polyphenol complexes strategy. The tannic acid (TA) and fulvic acid (FA) derived 0.3 Co/Fe–C catalysts show greatly similar morphologies, as well as the performance optimization process of electrocatalytic OER. Specifically, the TA-derived 0.3 Co/Fe–C catalyst exhibits an overpotential of 284 mV at 10 mA cm?2 for OER in alkaline electrolyte. Combined a series of characterization techniques suggest that abundant oxygen vacancies and favorable surface hydrophilicity can improve electronic conductivity of the catalyst and accelerate reactant adsorption and charge transfer rate on the catalyst surface, thus promoting OER activity of the catalysts. This study might provide a new perspective to construct advanced electrocatalysts with oxygen vacancies and hydrophilic surface for electrocatalytic applications. 相似文献
63.
Zhenwei Wang Haibin Sun Jiao Li Xue Guo Qiangqiang Hu Zanzhong Yang Fangyong Yu Guochang Li 《International Journal of Hydrogen Energy》2021,46(44):22932-22941
Aiming to lower the activation energy and expedite the oxygen reduction reaction (ORR) process of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathodes for application in intermediate-temperature solid oxide fuel cells (IT-SOFCs), Er0.4Bi1.6O3 (ESB) modified LSCF was prepared by infiltrating using organic solvents. The infiltration of ESB dramatically reduces the polarization resistances of LSCF cathodes (from 0.27 to 0.11 Ω cm2 at 700 °C, from 0.58 to 0.25 Ω cm2 at 650 °C), and lowers their activation energy (from 100.28 to 97.15 kJ mol?1). Also, ESB makes the rate-limiting step of LSCF cathodes at high frequency change from the charge transfer process on the cathode to the adsorption and diffusion of oxygen on cathode surface. The single cell with ESB infiltrated LSCF cathodes shows a peak power density of 469 mW cm?2 at 700 °C using humid hydrogen and air as fuels and oxidants, respectively, as well as a good short-term stability for 50 h. 相似文献
64.
65.
Weixuan Dong Hongbo Zhou Baodong Mao Zhengyuan Zhang Yashu Liu Yanhong Liu Fenghua Li Dongqi Zhang Dongxu Zhang Weidong Shi 《International Journal of Hydrogen Energy》2021,46(18):10773-10782
The synergistic achievement of low-cost earth-abundant electrocatalysts and high efficiency to meet renewable energy need is highly desirable yet challenging. Here, we developed a simple Ni foam self -templating route for V-doped Ni3S2 nanosheet arrays through in situ formation of metal-organic frameworks (MOFs) combined with subsequent conversion. The as-prepared MOF-V-Ni3S2/NF catalyst delivers outstanding electrocatalytic performance in the alkaline solution, which requires low overpotentials of 118.1 mV @10 mA cm?2 and 268 mV @10 mA cm?2 for hydrogen evolution reaction and oxygen evolution reaction, respectively. The V-doping and MOF-derived 3D hieratical nanostructure play a vital role in the catalytic process, which provides efficient active sites and large surface areas. Furthermore, an alkaline electrolyzer was assembled with two pieces of MOF-V-Ni3S2/NF, which achieves efficient water splitting at 1.58 V @10 mA cm?2. This strategy opens up new channels to synthesize MOF-based bifunctional electrocatalysts toward overall water spitting. 相似文献
66.
Haibin Sun Xue Guo Jiao Li Guochang Li Zanzhong Yang Hao Ding Weilu Yan Shuai Qi Peng Wang Youjie Song 《Ceramics International》2019,45(1):622-626
In order to clarify the effect of grain size on the electrical performance of BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) solid electrolytes with addition of NiO, microcrystalline (~1.5?µm) and ultrafine-grained (~280?nm) BZCYYb electrolytes (with 1?wt% NiO) were fabricated by the conventional and two-step sintering method, respectively. The results show that compared with microcrystalline electrolytes, the ultrafine-grained electrolytes have similar grain-interior conductivities, but much lower grain-boundary conductivities, illustrating that the grain boundary is not conducive for ionic transport. As a result, the electrical conductivity of microcrystalline electrolytes (1.9?×?10?2 S?cm?1 at 600?°C in wet air) is higher than that of ultrafine-grained electrolytes (1.1?×?10?2 S?cm?1 at 600?°C in wet air). In addition, the OCV (open-circuit voltage) values of electrolyte-supported single cells show that the undesired electronic conduction exists in the electrolytes due to the BaY2NiO5 impurity formed by the reaction of NiO and BZCYYb. The ultrafine-grained electrolytes show lower OCV values than that of microcrystalline ones, due to the prolonged electronic transport paths. Therefore, large-grained or grain boundary-free microstructure are necessary for improving the electrical performance of BZCYYb electrolytes. 相似文献
67.
Neutron capture therapy with Sulfur-33, similar to boron neutron capture therapy with Boron-10, is effective in treating some types of tumors including ocular melanoma. The key point in sulfur neutron capture therapy is whether the neutron beam flux and the resonance capture cross section of ~(33)S(n;α)~(30) Si reaction at 13.5 keV can achieve the requirements of radiotherapy. In this research,the authors investigated the production of 13.5 keV neutron production and moderation based on an accelerator neutron source. A lithium glass detector was used to measure the neutron flux produced via near threshold~7 Li(p,n)~7 Be reaction using the time-of-flight method. Furthermore, the moderation effects of different kinds of materials were investigated using Monte Carlo simulation. 相似文献
68.
Dr. Ma Su Dr. Yan Shi Minghui Wang Ruixuan Gao Jianfeng Wu Hai Xu Chuanwu Xi Prof. Jianfeng Cai 《ChemMedChem》2019,14(23):1963-1967
Host Defense Peptides (HDPs) have gained considerable interest due to the omnipresent threat of bacterial infection as a serious public health concern. However, development of HDPs is impeded by several drawbacks, such as poor selectivity, susceptibility to proteolytic degradation, low-to-moderate activity and requiring complex syntheses. Herein we report a class of lipo-linear α/urea-γ-AApeptides with a hybrid backbone and low molecular weight. The heterogeneous backbone not only enhances chemodiversity, but also shows effective antimicrobial activity against Gram-positive bacteria and is capable of disrupting bacterial membranes and killing bacteria rapidly. Given their low molecular weight and ease of access via facile synthesis, they could be practical antibiotic agents. 相似文献
69.
Zhuo Shi Ningning Dong Dingfeng Zhang Xiaofang Jiang Guanxin Du Shichao Lv Jiejie Chen Jun Wang Shifeng Zhou 《Journal of the American Ceramic Society》2019,102(7):3965-3971
The construction of nonlinear optical materials featuring asymmetric transmission of light is of great technological importance for various applications, including optical switching and optical power limiting. A significant challenge is the scalable fabrication of material candidates with good photochemical stability, high optical transmittance, and excellent optical limiting performance. Here, we present a nanocrystallization avenue for constructing hybrid optical limiting materials that exhibit ultrafast and robust optical limiting performance. The experimental results show that the controllable relaxation of a niobate glass may lead to the clustering of Nb-O units and contracting of the bandgap. It results in the notable improvement in nonlinear optical properties, including the enhanced saturation irradiance (380 GW/cm2), doubly increased nonlinear coefficient, and decreased limiting threshold (200 GW/cm2). Our results suggest a promising material that exhibits promising applications for protecting eyes and sensitive components from laser-induced damage. 相似文献
70.
Dongsheng Chen Longkai Shi Gaoxiang Song 《Journal of the American Oil Chemists' Society》2019,96(12):1315-1326
Soybean oil gums and soapstocks are important by-products that may potentially be contaminated by persistent organic pollutants (POP) such as polycyclic aromatic hydrocarbons (PAH) and phthalic acid esters (PAE), thus lowering the value when using them as starting materials to produce animal feed additives, food industry ingredients, and pharmaceutical products. In the present work, PAH and PAE distributions in these two types of by-products were detected using solvent extraction–solid phase extraction purification coupled with gas chromatography–mass spectrometry. Total PAH and PAE amounts in the soapstocks were significantly higher than those in the gums, thus indicating that neutralization showed much higher removal efficiency than degumming in terms of PAH and PAE eliminations. Meanwhile, the results proved that the concentrations of these two kinds of contaminants in the soybean oil gums and soapstocks were much higher than those in the soybean oils, suggesting that further investigations were needed and that the contents of PAH and PAE in soybean oil refining by-products should be carefully monitored and regulated. 相似文献