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311.
YBa2Cu3O7?δ /Ag thin film is prepared through pulsed laser deposition. The presence of Ag brings about significant inter- and intragranular modification in the microstructure of the composites. The resistive broadening in the tail part is suggested to be associated with the link between the grains and to be extremely sensitive to magnetic fields. It is assumed that the zero resistance state at the T c0 region of the above high temperature superconductor is governed by the excitations in the weak link network. Invoking Beans critical state model, enhancement in critical current density J c is observed. 相似文献
312.
N. Rajesh Mathivanan J. Jerald Puspita Behera 《The International Journal of Advanced Manufacturing Technology》2011,52(5-8):433-441
Fiber reinforced sandwich structures typically respond very poorly to transverse impact events. This paper is an attempt to investigate the impact response of sandwich panels subjected to low-velocity impact. Experimental investigations were carried out on the influence of three design factors: height of fall, core thickness, and impactor mass, which are the most relevant parameters to be considered for deflection. The study of behavior of the mentioned response was done by using Design of Experiments tool. Response surface methodology (RSM), a sequential experimentation strategy for model building, is used to model the response in order to determine the most significant factor among the influential factors. In this case, full factorial face-centered central composite design was chosen due to the number of factors and their levels in the study. The specimen consisted of face sheets made up of bi-woven glass fiber cloth with polyurethane foam as core material. The parametric analysis reveals that deflection increases steadily with an increase in the height of fall when compared with the impactor mass and the core thickness. The reason for this study is imperative for the next generation aircraft, marine, road, and rail vehicles with improved lightweight stiff materials that can absorb higher impact energy with higher resistance to deflection. 相似文献
313.
314.
In this paper, a three-level inverter-fed induction motor drive operating under Direct Torque Control (DTC) is presented.
A triangular wave is used as dither signal of minute amplitude (for torque hysteresis band and flux hysteresis band respectively)
in the error block. This method minimizes flux and torque ripple in a three-level inverter fed induction motor drive while
the dynamic performance is not affected. The optimal value of dither frequency and magnitude is found out under free running
condition. The proposed technique reduces torque ripple by 60% (peak to peak) compared to the case without dither injection,
results in low acoustic noise and increases the switching frequency of the inverter. A laboratory prototype of the drive system
has been developed and the simulation and experimental results are reported. 相似文献
315.
Ramesh C. Srivastava Sheelabhadra Mohanty Ramlal B. Singandhuppe Rajiv K. Mohanty Madhu S. Behera Lala I. P. Ray Deepika Sahoo 《Water Resources Management》2010,24(12):3017-3032
India has one of the largest and most ambitious irrigation programme in the world with net irrigated area exceeding 47 million
hectares. However, the overall project efficiency from the headwork to the farmer’s field has been quite low which leads to
not only poor utilization of irrigation potential created at huge cost, but also aggravates the degradation of soil and water
resources and thereby endangers the sustainability of agricultural production system. As the cost of creating additional irrigation
potential in terms of financial, human and environmental aspects has increased tremendously, need of the hour is to increase
the irrigation efficiency of existing projects and use saved water for irrigating new areas or meeting the demand of non-agricultural
sector. The contribution of application efficiency to poor irrigation efficiency is quite high and therefore increasing application
efficiency by a shift in application method from surface to pressurized system has potential of vastly improving irrigation
efficiency. To evaluate feasibility of this concept, a pilot study was initiated at Water Technology Centre for Eastern Region,
Bhubaneswar, on one outlet of a minor irrigation command. The system has been designed in such a way that it provides pipe
conveyance and surface irrigation for rice cultivation during monsoon season and pressurized irrigation during post monsoon
period through a hybrid system of sprinkler and drip with four outlets for sprinkler irrigating 2.8 ha area and two outlets
for drip irrigating 1.9 ha area. The system is also capable of providing irrigation through drip to part of a command during
summer for third crop using water stored in service reservoir after the canal is closed in first week of April. To take care
of sediment in the canal water, there are three stages of filtration: first by hydrocyclone filter which filters heavy suspended
materials viz. sand, silt, etc., then by the sand filter and finally by the screen filter. The filtration at three stages
reduces the turbidity to the desired level. It has been found that three-stage filtration reduced the turbidity to two NTU
which is within permissible limit. Considering the cost of water saved, a benefit-cost ratio of the system was found out to
be 1.126. This B: C ratio can be further increased by increasing the productivity of the fish and papaya in service reservoir
area and better crop management during summer season. 相似文献
316.
Heine JJ Behera M 《Journal of the Optical Society of America. A, Optics, image science, and vision》2006,23(4):806-815
An automated method is presented for analyzing signal-dependent noise. Signal-dependent noise is present in many types of data-acquisition processes and has been investigated by other researchers with various methods. Regardless of the noise analysis methods, often the starting point is based on a particular signal-dependent noise model, which also forms the basis for our study. The approach determines whether the estimated noise variance is dependent on the signal by approximating the functional relation within the constraints of the assumed signal-noise model. The method relies on the Fourier attributes of the signal and noise and uses the wavelet expansion for separating these components. The technique does not rely on the underlying noise and signal probability distributions. Two-dimensional simulations as well as mammography data are used to illustrate the merits of the approach. 相似文献
317.
Laxmidhar Rout Sridhar Regati Cong‐Gui Zhao 《Advanced Synthesis \u0026amp; Catalysis》2011,353(18):3340-3346
Efficient methods for the direct arylation and deacylative arylation of β‐ketophosphonates with iodoarenes in presence of a copper(I) or a copper(II) salt as the catalysts have been developed. The corresponding α‐arylphosphonates were obtained in high yields. A tentative mechanism for the deacylative arylation reaction was proposed on the basis of the experimental data. 相似文献
318.
Pooja Bhardwaj Rajni Kant Sthita Pragnya Behera Gaurav Raj Dwivedi Rajeev Singh 《International journal of molecular sciences》2022,23(11)
The early management, diagnosis, and treatment of emerging and re-emerging infections and the rising burden of non-communicable diseases (NCDs) are necessary. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas system has recently acquired popularity as a diagnostic tool due to its ability to target specific genes. It uses Cas enzymes and a guide RNA (gRNA) to cleave target DNA or RNA. The discovery of collateral cleavage in CRISPR-Cas effectors such as Cas12a and Cas13a was intensively repurposed for the development of instrument-free, sensitive, precise and rapid point-of-care diagnostics. CRISPR/Cas demonstrated proficiency in detecting non-nucleic acid targets including protein, analyte, and hormones other than nucleic acid. CRISPR/Cas effectors can provide multiple detections simultaneously. The present review highlights the technical challenges of integrating CRISPR/Cas technology into the onsite assessment of clinical and other specimens, along with current improvements in CRISPR bio-sensing for nucleic acid and non-nucleic acid targets. It also highlights the current applications of CRISPR/Cas technologies. 相似文献
319.
Satish Ranjan Pradhan Vishwa Mohan Behera Sushil Kumar Rathore Jnana Ranjan Senapati 《亚洲传热研究》2023,52(2):1754-1777
The present numerical study reports the combined effect of natural convection and radiation heat from a vertical cylinder with annular fins. The study involves simulation for laminar as well as turbulent regimes. For the present study, Rayleigh's number is varied in the range , emissivity in the range , and the fin spacing ratio (s/d) in the range . The radiation heat transfer has been found to share a considerable amount in the total heat transfer of the system for the laminar regime, but in the turbulent regime, its effect is minimal and can be neglected. When the fin spacing ratio is reduced, the total heat transfer increases for both the turbulent and laminar flow conditions. But the radiation heat increases with a reduction in fin spacing ratio for laminar and in case of turbulent flow radiation heat rate reduces with a reduction in s/d ratio. For the range of Rayleigh numbers considered in the present study, the Nusselt number increases with the increment of the fin spacing ratio. Thus, it can be concluded that there is a remarkable enhancement in the heat transfer rate in laminar cases with the fins. For turbulent cases, the fin efficiency lies between 40% and 50%. 相似文献
320.
Patankar Mahesh Kumar Kasinathan M. Behera R. P. Jayanthi T. Dhara Sandip 《SILICON》2022,14(7):3307-3315
Silicon - SiC is a well known wide band gap semiconductor explored for realizing the piezoresistive micro-electro-mechanical systems (MEMS) pressure sensors for harsh environments. In this work a... 相似文献