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51.
52.
Gels were made from recombined milks containing 0, 1.5 or 3.5% fat that were heated at 75, 80 or 90°C for 30 min, followed by acidification with glucono-8-lactone at 30°C. The rheological and microstructural properties of acid gels were investigated using dynamic low-amplitude oscillatory rheology and confocal scanning laser microscopy (CSLM). Heating milks, at temperatures ≥80°C, increased the storage moduli (G′) and decreased the gelation time. Recombined milks containing high fat (3.5%) had higher G′ than gels made from low-fat or skim milk. Milk heat treatment resulted in gels with a cross-linked microstructure. Recombined fat globules appeared to be embedded in the protein matrix.  相似文献   
53.
Corporate Strategy in the Intelligent Island: the Case of Singapore Telecom   总被引:1,自引:0,他引:1  
This paper focuses on the major telecommunications policiesand corporate strategies that have allowed Singapore to achievea high degree of success in designing and implementing a modernand high-quality telecommunications infrastructure. This successhas been achieved with a specific type of industry structurethat is marked by a single public organization protected frommarket competition by government regulations.  相似文献   
54.
This paper describes the experimental studies carried out on cracked austenitic stainless steel pipe and pipe welds under bending loads. Pipe welds were produced by gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW). Fracture resistance curves for pipe and pipe welds were compared. Results indicate that the fracture resistance of pipe and pipe weld (GTAW) is comparable but that of pipe weld (GTAW+SMAW) is inferior. Cracks do not deviate from their original plane during propagation as observed in the cases of carbon steel pipe and pipe welds. The fracture resistance of pipe welds does not depend on the loading histories to which it has been subjected prior to fracture test. Initiation and crack propagation were observed prior to the maximum moment. An existing limit load expression is applicable for the pipe base material but gives non‐conservative results for the pipe welds. Multiplication factors have been suggested for the pipe welds for evaluation of limit loads using the existing expression. Fracture resistance for the pipe and compact tension specimens have also been compared for base material and welds.  相似文献   
55.
In this paper, a novel digital watermarking scheme using fractional M-band dual tree complex wavelet transform (Fr-M-band-DT-CWT) is proposed. High frequency channels have wide bandwidth and low frequency channels have narrow bandwidth. These characteristics are suitable for analysing low frequency signal, but not for relatively high frequency signal. The images often contain many edges, which may cause rich middle and high frequency components in the 2-band wavelet domain. Therefore, the ordinary 2-band dual tree complex wavelet transform (DT-CWT) is not well-suited for analysing the image. So, the M-band DT-CWT with the FrFT called Fr-M-band-DT-CWT is proposed in this paper to address this problem. Further, we integrate the Fr-M-Band-DT-CWT with singular value decomposition (SVD) in order to enhance the performance. Experimental results of the proposed watermarking scheme are compared with the previously available watermarking algorithms, fractional Fourier transform (FrFT), fractional wavelet transform (FrWT). Further, the proposed watermark extraction scheme is also tested on different attacks. The results of the present investigations show that the proposed watermarking scheme is superior as compared to other existing watermarking schemes.  相似文献   
56.
AMIT KOHLI  HARI SINGH 《Sadhana》2011,36(2):141-152
In this paper, an effective procedure of response surface methodology (RSM) has been utilized for finding the optimal values of process parameters while induction hardening of AISI 1040 under two different conditions of the material i.e., rolled and normalized. Various process parameters, such as feed rate (speed at which the induction coil moves, which is measured in mm/sec), current, dwell time (time after which heat intensity starts to heat work piece in seconds) and gap between the work piece and induction coil have been explored by experiments. Hardness at two different conditions has been considered as performance characteristic. The experiment plan was based on rotatable, central composite design (CCD). The experimental results showed that the proposed mathematical models suggested could describe the performance indicators within the limits of the factors being investigated. The obtained optimal process parameters have been predicted and verified by confirmation experiments. Microstructure and SEM (scanning electron microscope) analyses were also done for justification of the work.  相似文献   
57.
An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident electromagnetic wave considering the effect of collisions in plasma layers. The dispersion relation is derived by using the transfer matrix method and the boundary conditions based on electromagnetic theory. The dispersion curves are plotted for both the normal photonic band gap structure and the absorption photonic band gap structure. It is found that the increase in the angle of incidence shifts the photonic band gap toward higher frequencies. Also, the cutoff frequency is independent of collisions.  相似文献   
58.
Outer layers of cotyledons of pigeonpea cultivar C 11 were successively scarified using a Tangential Abrasive Dehulling Device (TADD). Scarification for 0; 2, 4, 8, and 12 min resulted in the removal of 0, 6.7, 12.7, 25.3, and 36.9%, respectively, of powder fractions. The cotyledons and powder fractions at each level of scarification were analyzed for chemical composition, including minerals and trace elements, protein fractions, amino acid composition, and trypsin inhibitor acitivity (TIA). Protein, soluble sugars and ash of the dhal fraction (scarified cotyledons) decreased with increasing scarification time, while starch content increased. Considerable amounts of calcium (about 20%) and iron (about 30%) were removed by scarification for 4 min, but the process did not adversely affect protein quality in terms of amino acids. Trypsin inhibitors were not removed substantially by scarification.  相似文献   
59.
Residence times of 1.0-2.0 cm potato cubes with 0.4-1.2% aqueous solutions of sodium carboxymethyl cellulose flowing at 453-599 mli sec were investigated in a vertical scraped surface heat exchanger rotating at 60 160 rpm. Minimum and maximum normalized particle residence times (NPRTs) standard deviation of mean NPRTs, and characteristic parameter for tanks-in-series models were not significantly affected by particle concentration. Mean NPRT for 40% particle concentration was significantly higher than those of single particle - 20% particle concentrations. Mean NPRTs were significantly influenced by process parameters and 2-way interactions.  相似文献   
60.
The roles of electrolyte composition and surface treatments in the phenomenon of asymmetric polarization in sodium β"-alumina ceramics are investigated. The results indicate that Asymmetric polarization is only displayed by electrolyte compositions containing 80 vol%β"-alumina phase and that a chemical treatment utilizing phosphoric acid, or a water treatment, is effective in circumventing the asymmetric polarization via removal of the asymmetric-polarization-causing resistive surface film. The surface film is soda rich, 20 to 40 nm thick, and there is a considerable concentration gradient from the surface into the bulk of an as-sintered sodium β"-alumina electrolyte.  相似文献   
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