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排序方式: 共有472条查询结果,搜索用时 15 毫秒
461.
Tantalum oxynitride (TaOxN1−x) fibers were synthesized and evaluated for their electrocatalytic hydrogen activity using an in-house developed centrifugal spinning setup. By tailoring the composition of the spinning solution and optimizing collector distance and rotation speed of the spinneret, bead-free TaOxN1−x fibers with a diameter of 800 nm were obtained. The fibers were structurally characterized through phase and elemental analysis, confirming the formation of monoclinic TaOxN1−x with clear splitting of the X-ray photoelectron spectroscopy peaks indicating Ta was in +5 oxidation state. The resulting oxynitride fibers exhibited superior electrocatalytic performance with low overpotentials (250 mV) to generate 10 mA/cm2 compared to Ta2O5 oxide fibers. Interestingly, the enhanced activity of oxynitride fibers was observed to be suppressed in basic medium due to the high oxophilicity of tantalum ions and a negative Gibbs adsorption-free energy, leading to poisoning of the active sites. This work demonstrates a facile pathway for the fabrication of high-performance electrocatalysts, based on TaOxN1−x fibers, from a cost-effective and energy-efficient centrifugal spinning technique.  相似文献   
462.
Gupta  Abhinav  Rai  Manish Kumar  Pandey  Amit Kumar  Pandey  Digvijay  Rai  Sanjeev 《SILICON》2022,14(13):7577-7584
Silicon - The double gate junctionless transistor (DG-JLT) has become the most promising device in sub nano-meter regime. DGJLT based circuits have improved performance and simpler fabrication than...  相似文献   
463.
Severe hyperlipidemia is a risk factor for cardiovascular disease. Children with chronic kidney disease and end stage renal disease are at risk for development of hyperlipidemia. In this report, we describe a 7-month-old male infant with Denys–Drash syndrome who was found to have a “milky-layer” floating on the deaerator of the hemodialysis machine. Investigations showed severe hypertriglyceridemia of >1000 mg/dl. The patient had been on chronic continuous manual peritoneal dialysis until 6 months of age and recently had been switched to hemodialysis. Management included lowering of caloric intake and addition of medium chain triglyceride with reduction of the serum triglyceride levels to 300–400 mg/dl. Close monitoring of serum lipids and timely intervention is important to prevent serious complications associated with dyslipidemia. Observation of the “milky layer” in the deaerator of the hemodialysis machine may be an interesting visual clue of underlying severe hypertriglyceridemia.  相似文献   
464.
Antibiotic resistance has emerged as a global threat due to the ability of bacteria to quickly evolve in response to the selection pressure induced by anti-infective drugs. Thus, there is an urgent need to develop new antibiotics against resistant bacteria. In this review, we discuss pathways involving bacterial protein biogenesis as attractive antibacterial targets since many of them are essential for bacterial survival and virulence. We discuss the structural understanding of various components associated with bacterial protein biogenesis, which in turn can be utilized for rational antibiotic design. We highlight efforts made towards developing inhibitors of these pathways with insights into future possibilities and challenges. We also briefly discuss other potential targets related to protein biogenesis.  相似文献   
465.
International Journal of Information Security - Rapid growth of network technologies necessitates the evolution and reconfiguration of network policies. The rigid nature of legacy networks is a...  相似文献   
466.
Gupta  Abhinav  Rai  Sanjeev  Kumar  Nitish  Sigroha  Deepak  Kishore  Arunabh  Pathak  Varnika  Rahman  Ziya Ur 《SILICON》2022,14(3):1005-1012
Silicon - It is a well-known fact that the gate stacking is used to improve the electrostatic behavior of Si0.5Ge0.5 Junctionless Gate-All-Around (JL-GAA) MOSFETs. In gate stacking, the high-k...  相似文献   
467.
Kumar  Nitish  Awasthi  Himanshi  Purwar  Vaibhav  Gupta  Abhinav  Dubey  Sarvesh 《SILICON》2022,14(6):2679-2686
Silicon - Silicon-based Nanotube Junction-less Double-Gate-All-Around (NJL-DGAA) MOSFETs has become a promising solution to high-speed ULSI chip design. However, the change in surrounding...  相似文献   
468.
The present study is focused on a medical problem called stenosed carotid artery. The problem is formulated with the help of a two-phase blood flow model. The non-Newtonian nature of blood is considered that hold power law. Physical quantities were expressed in tensorial form. Analytical and numerical methods are used to solve equations under given boundary conditions. The effects of various parameters on blood flow like stenosis size, flow flux, resistance, haematocrit, pressure drop, etc. were studied and shown through various graphs. Parameter k , which ensures that the fluid is Newtonian or non-Newtonian; its impact on pressure drop; resistance to flow; and flow flux were obtained during the disease and presented through the graph. A relationship between pressure drop and haematocrit was obtained, which was helpful to predict fluctuation in blood flow during stenosis. We have also given a medical use for this model with the help of pathological data. We also analyzed steady and laminar flow in a carotid artery for different heights of stenosis. The study of various physiological parameters has been performed on the basis of blockage percentage and concentration of haematocrit. The nature of the red blood corpuscle (RBC) phase is considered liquid packets in a semi-permeable membrane, which makes this model close to reality.  相似文献   
469.
The Internet of Everything (IoE) based cloud computing is one of the most prominent areas in the digital big data world. This approach allows efficient infrastructure to store and access big real-time data and smart IoE services from the cloud. The IoE-based cloud computing services are located at remote locations without the control of the data owner. The data owners mostly depend on the untrusted Cloud Service Provider (CSP) and do not know the implemented security capabilities. The lack of knowledge about security capabilities and control over data raises several security issues. Deoxyribonucleic Acid (DNA) computing is a biological concept that can improve the security of IoE big data. The IoE big data security scheme consists of the Station-to-Station Key Agreement Protocol (StS KAP) and Feistel cipher algorithms. This paper proposed a DNA-based cryptographic scheme and access control model (DNACDS) to solve IoE big data security and access issues. The experimental results illustrated that DNACDS performs better than other DNA-based security schemes. The theoretical security analysis of the DNACDS shows better resistance capabilities.  相似文献   
470.
Sodium-ion batteries are becoming potential solutions for replacement of batteries due to the abundance of sodium reserves and high recycling costs of lithium-based batteries. Sodium-based layered oxides are being widely explored as positive electrode material for sodium-ion battery due to their high capacities and high energy densities. However, oxide-based systems do suffer from thermal stability issues and exhibit low power density. On the other hand, polyanionic-based compounds and Prussian blue analogues demonstrate appreciable thermal stabilities and are useful in high power density applications. This article reviews recent trends of these cathode materials.  相似文献   
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