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排序方式: 共有3143条查询结果,搜索用时 10 毫秒
991.
Rajeev Sharma Sujata Pandey Shail Bala Jain 《Journal of Computational Electronics》2011,10(1-2):201-209
A two dimensional analytical model for nanoscale fully depleted double gate SOI MOSFET is presented. Green??s function solution technique is adopted to solve the two dimensional Poisson??s equation using Dirichlet??s and Neumann??s boundary conditions at silicon-silicon di-oxide interface. Based on the derived 2D potential distribution, surface potential distributions in the Si film are analytically obtained. The calculated minimum surface potential is used to develop an analytic threshold voltage model. Simulation is done using ATLAS simulator for a 65?nm device and the results obtained are compared with the proposed 2D model. The model results are found to be in good agreement with the simulated data and other published results. 相似文献
992.
Silicon - In this paper, through TCAD simulations, we show that the introduction of a thin paraelectric (PE) layer between the ferroelectric (FE) and dielectric (DE) layers in an MFIS structure,... 相似文献
993.
Satish Kumar Singh Abhijit Maiti Aaditya Pandey Nishant Jain Chhaya Sharma 《应用聚合物科学杂志》2023,140(2):e53295
The scarcity of freshwater is one of the major challenges to the civilized community around the World. So, the various engineered processes have been developed for the remediation of this problem such as osmotic pressure-driven processes (OPDPs). OPDPs includes forward osmosis and pressure retarded osmosis, which have gained enormous attention and becoming a flexible membrane-based technology for desalination and wastewater treatment. The most significant components of the OPDPs to be efficient are the membranes and the draw solution. Although numerous studies highlighted the membrane fouling and concentration polarization are one of the critical parameters to assess the system efficiency in the OPDPs and other pressure driven membrane processes. This study delivers an up-to-date review of the OPDPs in terms of concentration polarization, membrane fouling (organic, inorganic, and biofouling), foulant interactions, remedial strategies, monitoring and characterization techniques, and future directions of research. Numerous foulant interactions are also elaborated for the OPDPs in the field of the membrane separation technique. State of the art in antifouling membrane fabrication methods are critically reviewed along with different remedial strategies for fouled membranes in OPDPs. 相似文献
994.
This article reports the synthesis and characterisation of Barium titanate (BaTiO3) nanocomposite and its application as opto-electronic humidity sensor. Titanium tetrachloride and barium hydroxide were mixed in molar ratio 1?:?1 in deionised water under continuous stirring at room temperature. Later, sodium hydroxide solution was added to above solution with continuous stirring. Finally, BaTiO3 gel was obtained. The synthesised nano-composite material was characterised using a scanning electron microscope, X-ray diffraction (XRD) and UV-Visible spectrophotometer. SEM image of the composite film shows that the film is porous having uniform grains. From XRD the minimum crystallite size of BaTiO3 was found to be 8?nm using Debye–Scherer formula. UV-Visible absorption spectroscopy was used for optical characterisation of the film. It was found that the optical band gap of the composite material was 3.50?eV. Barium titanate thin film was deposited on the base of an equilateral prism using sol–gel spin coating process at 4000?rpm. The humidity sensing properties of the film was investigated at different angles of incidence. It was observed that the intensity of reflected light increased with an increase in relative humidity (%RH) in the range 5–95% at a particular angle of incidence. Sensing element has maximum sensitivity ~6?µW/%RH, which is quite significant for sensor fabrication purposes. 相似文献
995.
The monodispersion of magnetic nanoparticles in conducting polymer is the prerequisite to make a high quality composite for tunable electromagnetic interference (EMI) shielding. To meet this challenge, we have designed and synthesized ferrofluid based nanoarchitectured polypyrrole composites containing Fe3O4 (8–12 nm) via in situ oxidative polymerization. To tune the microwave signals, polypyrrole composites (PFF) with different monomer/ferrofluid weight ratios have been prepared and characterized in microwave frequency domain. A maximum shielding effectiveness value of SEA(max) = 20.4 dB (∼99% attenuation) due to the absorption of microwave has been observed in the frequency range of 12.4–18 GHz and attenuation level varied with ferrofluid loading. The electrical conductivity of PFF composite is of the order of 10−2 S cm−1 order and having superparamagnetic nature with saturation magnetization (Ms) of 5.5 emu g−1. The lightweight PFF composites with high attenuations can provide full control over the atomic structure and are favorable for the practical EMI shielding application for commercial electronic appliances. 相似文献
996.
In this work, Copper Indium disulfide (CIS) nanoparticles of size ∼ 5 nm were prepared via solvothermal approach in ethanol under the nitrogen atmosphere using copper chloride, indium chloride and thiourea (Tu) as starting materials, without any assistance through organic ligands at the reaction temperature of 150 °C. The factors which might affect the morphology, structure, phase of the product during the synthesis were discussed. It was found that the products were significantly affected by the reaction time and solvent. The morphology, structure, phase constituents and optical properties of the as prepared CIS powders were characterized by X-ray diffraction (XRD), Energy dispersive Spectroscopy (EDS), scanning electron microscopy (SEM) and ultraviolet–visible (UV–Vis) spectrometry respectively. The result shows that the CIS nanoparticles can be synthesized by solvothermal method at a reaction time of 2 h and shows that when the reaction time was increased from 2 h to 48 h, CIS porous flower like nanoparticles were obtained as we increase the reaction time. We also observed that in this process, the phase selection of WZ-CIS or CH-CIS is greatly influence by solvent. We also observed that, in this process sulfur source did not influence the phase but participated in the growth of the nanoparticles. 相似文献
997.
Transient Electronics: Dissolvable Metals for Transient Electronics (Adv. Funct. Mater. 5/2014) 下载免费PDF全文
998.
Lan Yin Huanyu Cheng Shimin Mao Richard Haasch Yuhao Liu Xu Xie Suk‐Won Hwang Harshvardhan Jain Seung‐Kyun Kang Yewang Su Rui Li Yonggang Huang John A. Rogers 《Advanced functional materials》2014,24(5):645-658
Reactive dissolution and its effects on electrical conduction, morphological change and chemical transformation in thin films of Mg, AZ31B Mg alloy, Zn, Fe, W, and Mo in de‐ionized (DI) water and simulated body fluids (Hanks’ solution pH 5–8) are systematically studied, to assess the potential for use of these metals in water‐soluble, that is, physically "transient", electronics. The results indicate that the electrical dissolution rates in thin films can be much different that traditionally reported corrosion rates in corresponding bulk materials. Silicon metal oxide field effect transistors (MOSFETs) built with these metals demonstrate feasibility for use in transient electronics. 相似文献
999.
Image denoising by supervised adaptive fusion of decomposed images restored using wave atom,curvelet and wavelet transform 总被引:1,自引:0,他引:1
This paper presents an efficient image denoising method that adaptively combines the features of wavelets, wave atoms and curvelets. Wavelet shrinkage is used to denoise the smooth regions in the image while wave atoms are employed to denoise the textures, and the edges will take advantage of curvelet denoising. The received noisy image is firstly decomposed into a homogenous (smooth/cartoon) part and a textural part. The cartoon part of the noisy image is denoised using wavelet transform, and the texture part of the noisy image is denoised using wave atoms. The two denoised images are then fused adaptively. For adaptive fusion, different weights are chosen from the variance map of the denoised texture image. Further improvement in denoising results is achieved by denoising the edges through curvelet transform. The information about edge location is gathered from the variance map of denoised cartoon image. The denoised image results in perfect presentation of the smooth regions and efficient preservation of textures and edges in the image. 相似文献
1000.
Abhishek Kumar Jain Khoa Dang Pham Jin Cui Suhaib A. Fahmy Douglas L. Maskell 《Journal of Signal Processing Systems》2014,77(1-2):61-76
Emerging hybrid reconfigurable platforms tightly couple capable processors with high performance reconfigurable fabrics. This promises to move the focus of reconfigurable computing systems from static accelerators to a more software oriented view, where reconfiguration is a key enabler for exploiting the available resources. This requires a revised look at how to manage the execution of such hardware tasks within a processor-based system, and in doing so, how to virtualize the resources to ensure isolation and predictability. This view is further supported by trends towards amalgamation of computation in the automotive and avionics domains, where such properties are essential to overall system reliability. We present the virtualized execution and management of software and hardware tasks using a microkernel-based hypervisor running on a commercial hybrid computing platform (the Xilinx Zynq). The CODEZERO hypervisor has been modified to leverage the capabilities of the FPGA fabric, with support for discrete hardware accelerators, dynamically reconfigurable regions, and regions of virtual fabric. We characterise the communication overheads in such a hybrid system to motivate the importance of lean management, before quantifying the context switch overhead of the hypervisor approach. We then compare the resulting idle time for a standard Linux implementation and the proposed hypervisor method, showing two orders of magnitude improved performance with the hypervisor. 相似文献