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81.
Multistage interconnection networks (MINs) are widely used for reliable data communication in a tightly coupled large-scale multiprocessor system. High reliability of MINs can be achieved using fault tolerance techniques. The fault tolerance is generally achieved by disjoint paths available through multiple connectivity options. The gamma interconnection network (GIN) is a class of fault tolerant MINs providing alternate paths for source–destination node pairs. Various 2-disjoint and 3-disjoint GIN architectures have been presented in the literature. In this paper, two new designs of 4-disjoint paths multistage interconnection networks, called 4-disjoint gamma interconnection networks (4DGIN-1 and 4DGIN-2) are proposed. The proposed 4DGINs provide four disjoint paths for each source–destination pair and can tolerate three switches/link failures in intermediate interconnection layers. Proposed designs are highly reliable GIN with higher fault-tolerant capability than other gamma networks at low cost. Terminal pair reliabilities of proposed designs and various other 2-disjoint and 3-disjoint GINs are evaluated, analyzed and compared. Reliability values of proposed designs are found higher.  相似文献   
82.
Analysis of saponins by thin layer chromatography (TLC) is reported. The solvent system was n-butanol:water:acetic acid (84:14:7). Detection of saponins on the TLC plates after development and air-drying was done by immersion in a suspension of sheep erythrocytes, followed by washing off the excess blood on the plate surface. Saponins appeared as white spots against a pink background. The protocol provided specific detection of saponins in the saponins enriched extracts from Aesculusindica (Wall. ex Camb.) Hook.f., Lonicera japonica Thunb., Silene inflata Sm., Sapindusmukorossi Gaertn., Chlorophytum borivilianum Santapau & Fernandes, Asparagusadscendens Roxb., Asparagus racemosus Willd., Agave americana L., Camellia sinensis [L.] O. Kuntze. The protocol is convenient, inexpensive, does not require any corrosive chemicals and provides specific detection of saponins.  相似文献   
83.
Nowadays, the development of refined image processing and software editing tools has finish the exploitation of digital images easily and invisible the image to the normal eyes and this process known as image fakery. Image security is one of the key issues in any field that makes use of digital images. Copy-move forgery (CMF) is the most effective and simple scheme to create forged digital images. In general, the methodologies based on Scale Invariant Feature Transform (SIFT) are widely used to detect CMF. Unfortunately, the detection performance of all SIFT based CMF detection approaches are extremely dependent on the selection of feature vectors. The values of these parameters are often determined through experience or some experiments on a number of forgery images. However, these experience parameter values are not applicable to every image thereby offers a limited usefulness. This paper deals the CMF problem using improved Relevance Vector Machine technique. The key idea of the IVRM is to apply Biorthogonal Wavelet Transform based scheme on image for feature extraction. The feature vectors are then stored lexicographically and similarity of vectors is decided using Minkowski distance and threshold value. The simulation results of proposed technique show a significant improvement in accuracy, sensitivity, and specificity rates over others existing schemes.  相似文献   
84.
3,6-diarylcarbazole derivatives, 3,6-di-(p-cyanophenyl)-N-hexylcarbazole (CNHC) and 3,6-di-(p-acetylphenyl)-N-hexylcarbazole (ANHC) were synthesized, characterized and energy levels determined. Steady state fluorescence of these molecules showed blue emission in thin films. Blends of these molecules with N,N′-diphenyl-N,N′-(bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD) showed exciplex emission as the dominant one. Single layer organic light emitting devices (OLEDs) of CNHC, ANHC and their blends with TPD were fabricated using ITO as anode and Ca as cathode. The blend film devices showed pure exciplex electroluminescence.  相似文献   
85.
This paper presents the mechanical and tribological characteristics of the NiTi shape memory alloy (SMA) fabricated by powder metallurgy. This material has prominent applications in micro-electromechanical systems, medical implants, actuator, space and aerospace industries, etc. In every field, wear characteristics plays a dominating role. In present work dry-abrasion wear behavior is determined for NiTi alloy by varying binder percentage. With increasing binder percentage from 2.5 to 15 %, density decreases from 6.5 to 5.3 g/cm3 while porosity increases from 19 % to 51 %. Increasing rotational speed and binder percentage at a constant load the wear rate increases in the NiTi alloy. Due to the presence of hard particles, NiTi exhibits a very small wear rate. The coefficient of friction is also computed for the alloys in present research work. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction were used for the investigation of surface morphology and phases in the NiTi alloy.  相似文献   
86.
Calcium chloride is an essential calcium channel agonist which plays an important role in the contraction of muscles by triggering calcium channel. First time hypothesized about its role in the treatment of GER (gastro-esophageal reflux) and vomiting disorder due to its local action. There are two objectives covered in this study as first, the development and optimization of floating formulation of calcium chloride and another objective was to evaluate optimized formulation through gamma scintigraphy in human subjects. Gastro retentive formulation of calcium chloride was prepared by direct compression method. Thirteen tablet formulations were designed with the help of sodium chloride, HPMC-K4M, and carbopol-934 along with effervescing agent sodium bicarbonate and citric acid. Formulation (F8) fitted best for Korsmeyer–Peppas equation with an R2 value of 0.993. The optimized formulation was radiolabelled with 99mTc-99?m pertechnetate for its evaluation by gamma scintigraphy. Gastric retention (6?h) was evaluated by gamma scintigraphy in healthy human subjects and efficacy of present formulation confirmed in GER positive human subjects. Gamma scintigraphy results indicated its usefulness in order to manage GERD. Stability studies of the developed formulation were carried out as per ICH guidelines for region IV and found out to be stable for 24?months.  相似文献   
87.
Security considerations in ad hoc sensor networks   总被引:1,自引:0,他引:1  
In future smart environments, ad hoc sensor networks will play a key role in sensing, collecting, and disseminating information about environmental phenomena. As sensor networks come to be wide-spread deployment, security issues become a central concern. So far, the main research focus has been on making sensor networks feasible and useful, and less emphasis has been placed on security. This paper analyzes security challenges in wireless sensor networks and summarizes key issues that need be solved for achieving security in an ad hoc network. It gives an overview of the current state of solutions on such key issues as secure routing, prevention of denial-of-service, and key management service.  相似文献   
88.
The effects of nonpozzolanic (marble dust) and pozzolanic (rice husk ash) mineral admixtures on the hydration behavior and mechanical properties of ordinary Portland cement (OPC) have been investigated. The blending of both marble dust (20-60%) and rice husk ash (10-30%) in OPC accelerate the setting as compared to control (OPC). Marble dust addition decreases the strength of OPC and the maximum strength of 54.5 MPa has been achieved on 28 days of curing with 20% of marble dust (CM20). Addition of rice husk ash increases the strength and maximum strength of 65.9 MPa has been observed with 20% of RHA (CR20) blended cement. The formation of various crystalline phases and their effects on hydration behavior of mineral admixtures blended cement were examined by X-ray diffraction (XRD). The changes in microstructure of the hydrated samples were also studied using scanning electron microscope (SEM).  相似文献   
89.
This article describes the experimental results of the polyvinylidene fluoride (PVDF)/Potassium nitrate (KNO3), composite films. To explain the nature of ferroelectric phase (phase III) of potassium nitrate (KNO3), we have prepared the composite films of poly (vinylidene fluoride)/potassium nitrate in the relative amount of 50–50 wt.% by using simple melt pressing. The results of the temperature dependence of the capacitance and conductance of the composite films have been carried out. The current vs. voltage (I-V) characteristics exhibit the polarization current, which is the nature of ferroelectricity in the composite films. Capacitance vs. voltage (C-V) measurements have been performed to identify the ferroelectric properties of the composite films.  相似文献   
90.
Metal nanoparticles have generated great interest due to their excellent optical and chemical properties. The widely used chemical method for synthesising nanoparticles involves capping agents for colloidal stability. However, there are scarce reports on the application of metal nanoparticles synthesised without using capping agents. Hence, there is a need to develop pristine nanoparticles devoid of capping that can be used for translational research. Here, the authors developed a facile and rapid method for synthesising bare metal nanoparticles (platinum/silver/gold) that are chemically reactive and stable for a month upon storage. They synthesised bare metal nanoparticles of sub‐15 nm and characterised using standard techniques (UV–VIS‐NIR/DLS/zeta//TEM/XRD). They assessed the safety of the synthesised nanoparticles on the liver carcinoma cell line (HepG2). Bare gold and platinum nanoparticles were non‐toxic in comparison to bare silver nanoparticles. Bare metal nanoparticles were also checked for metal detection wherein antimony, mercury and chromium were detected using bare gold and silver nanoparticles. The spectroscopic shifts of the nanoparticles when bound to metals resulted in blue and red shifting of the plasmon band, indicating the sensing of metals. These results show that bare metal nanoparticles have the potential to emerge as a promising candidate for biomedical and sensing applications.Inspec keywords: ultraviolet spectra, electrokinetic effects, liver, cellular biophysics, nanoparticles, cancer, toxicology, gold, platinum, X‐ray diffraction, silver, colloids, transmission electron microscopy, plasmonics, visible spectra, nanomedicineOther keywords: bare plasmonic metal nanoparticles, liver carcinoma cell line, capping agents, pristine nanoparticles, bare metal nanoparticles, synthesised nanoparticles, platinum nanoparticles, silver nanoparticles, XRD, TEM  相似文献   
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