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41.
V2O5/AC具有很好的烟气同时脱硫脱硝能力,脱硫过程包括其对烟气中SO2的吸附、吸附饱和后SO2从其上的脱附(再生)及脱附出SO2的资源化。考察了同时脱硫脱硝后的V2O5/AC在含NH3气氛中的再生和硫资源化的耦合过程。研究了NH3注入量、再生温度、再生时间和尾气循环流量对再生效率、硫回收率及二次脱硫脱硝活性的影响。结果表明,再生温度和再生时间主要影响SO2的脱附,因而影响再生效率和二次脱硫脱硝活性;NH3注入量不影响SO2的脱附,但明显影响硫回收率和二次脱硫脱硝活性;尾气循环模式是提高硫回收率的重要方法,但在研究的条件下循环流量对再生效率、硫回收率和二次脱硫脱硝活性的影响不大。 相似文献
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YBCO线圈的交流损耗直接关系到YBCO设备的运行成本及稳定性。实现对YBCO线圈交流损耗的快速、准确测量,对于开展YBCO涂层导体的应用研究具有重要的意义。文中采用电测量法,在77K、零场和不同频率条件下,对YBCO线圈通以不同运行电流时产生的交流传输损耗进行测量。构建了YBCO线圈交流损耗的数值计算模型,对YBCO线圈交流损耗进行理论研究,最后将实验数据与理论计算结果进行比较,两者结果基本一致。可以发现,YBCO线圈在频率低于75Hz时,交流传输损耗随频率的增大而减小,当频率从75Hz增加到195Hz时,交流传输损耗随频率的增大而增加。 相似文献
44.
The peak effect (PE) in the critical current density in both low and high temperature superconductors has been the subject
of a large amount of experimental and theoretical work in the last few/several years. In the case of YBCO, crucial discussions
describing a dynamic or a static picture are not settled. In that region of field and temperature the mobility of the vortex
lattice (VL) is found to be dependent on the dynamical history. Recently we reported evidence that the VL reorganizes and
accesses to robust VL configurations (VLCs) with different effective pinning potential wells arising in response to different
system histories. One of the keys to understand the nature of the PE is to investigate the VL behavior in the vicinity of
the various VLCs in the region of the PE. The stability of these VLCs was investigated and it was found that they have distinct
characteristic relaxation times, which may be related to elastic or plastic creep processes. In this paper we review some
of these results and propose a scenario to describe the PE in YBCO crystals. 相似文献
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AC Conduction and Time–Temperature Superposition Scaling in a Reduced Graphene Oxide–Zinc Sulfide Nanocomposite
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Koushik Chakraborty Poulomi Das Sankalpita Chakrabarty Dr. Tanusri Pal Dr. Surajit Ghosh 《Chemphyschem》2016,17(10):1518-1523
We report, herein, the results of an in depth study and concomitant analysis of the AC conduction [σ′(ω): f=20 Hz to 2 MHz] mechanism in a reduced graphene oxide–zinc sulfide (RGO–ZnS) composite. The magnitude of the real part of the complex impedance decreases with increase in both frequency and temperature, whereas the imaginary part shows an asymptotic maximum that shifts to higher frequencies with increasing temperature. On the other hand, the conductivity isotherm reveals a frequency‐independent conductivity at lower frequencies subsequent to a dispersive conductivity at higher frequencies, which follows a power law [σ′(ω)∝ωs] within a temperature range of 297 to 393 K. Temperature‐independent frequency exponent ′s′ indicates the occurrence of phonon‐assisted simple quantum tunnelling of electrons between the defects present in RGO. Finally, this sample follows the “time–temperature superposition principle”, as confirmed from the universal scaling of conductivity isotherms. These outcomes not only pave the way for increasing our elemental understanding of the transport mechanism in the RGO system, but will also motivate the investigation of the transport mechanism in other order–disorder systems. 相似文献
48.
《应用有机金属化学》2017,31(12)
In this study, the potential application of copper nanowires loaded on activated carbon for simultaneous removal of Disulfine blue (DB), Crystal violet (CV) and Sunset yellow (SY) has been described. The relation between adsorption properties with variables such as solution pH, adsorbent value, contact time and initial dyes concentration was investigated and optimized. A three‐layer artificial neural network (ANN) model was utilized to predict dyes removal (%) by adsorbent following conduction of experiments. The training of network at above mention experimental data confirms its ability to forecast the removal performance with a linear transfer function (purelin) at output layer. The Levenberg–Marquardt algorithm and tangent sigmoid transfer function (tansig) with 16 neurons at the hidden layer was applied. Parameters were optimized by central composite design (CCD) combined with response surface methodology (RSM) and desirability function. The accuracy of ANN was judged according to both MSE and AAD% at optimal conditions and results indicate its superiority to RSM model in term of higher R2 and lower AAD% values. This observation was also corroborated by the parity plots between the predicted and experimental values. The ANN model was better in both data fitting and prediction capability in comparison to RSM model. 相似文献
49.
Shen Ting-gen Zhou Yue-qun Ge Jun Yu Feng-chao Ji Pei-lai Wang Gang 《Journal of Russian Laser Research》2008,29(3):255-261
The method of finite-difference-time domain (FDTD) was used to study the characteristics of the patch antenna based on drilling
air holes in the PBG substrate. The results obtained show that the waves propagating along the substrate surface can be suppressed
by the drilled photonic crystal band gap (PBG) structure due to the influence of its forbidden band. The energy of the electromagnetic
waves is concentrated mainly in the substrate. As a result, patch antennas based on drilling air holes in the PBG substrate
have lower return losses (S11) in comparison with the conventional patch antennas; thus, a high gain is reached and the performance
is improved. Due to such the advantages, the use of patch antennas can be extended to such fields as mobile communication,
satellite communication, aviation, etc. 相似文献
50.
New phase formation at the La0.9Sr0.1MnO3/YSZ interface and its effects on the cathodic performances were studied at 900 °C in air. The resistance caused by the interfacial product layer kept increasing with time to reach up to 40% of the total resistance after 500 h. The interfacial product was identified as La2Zr2O7 by XRD measurement. The electrical conductivity of La2Zr2O7 (2.4 × 10−5 S cm−1 at 1000 °C), measured by AC impedance and current interruption methods, was 4 to 7 orders of magnitude smaller than those of La0.9Sr0.1MnO3 electrode or YSZ electrolyte. Either the electronic conductivity or the electrochemical O2 reduction activity of La2Zr2O7 was negligible. Combining these results, a conclusion was made that the cathodic degradation comes mainly from the growth of interfacial product layer and its contribution to the cell resistance increment is ohmic in nature. 相似文献