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41.
The glucose is considered to affect the quality of the dried egg products; therefore the statistical optimization of desugarization process parameters of Liquid whole egg (LWE) was carried out in this study. The fermentation of Liquid whole egg (LWE) was done using compressed baker’s yeast. A polynomial model was regressed between reducing sugar & desugarization conditions. The coefficient of determination (R2) of 0.998 (P < 0.0001) for the regressed model indicated about the adequacy of the model, which implies the model was significant to predict reducing sugar content at different fermentation conditions. Optimum conditions for complete desugarization of Liquid whole egg (LWE) were found to be time 6.49 h, temperature 28 °C, pH 6.40 and yeast concentration 3.8 g/L and confirmed by conducting actual experiments at these conditions.  相似文献   
42.
We introduce two extremely low quiescent current (I Q ) low-dropout (LDO) voltage regulators. The Low I Q -LDO (LI Q -LDO) uses 13 μA of total quiescent current and is designed for a maximum load current of 50 mA. The Micro I Q -LDO (MI Q -LDO) uses only 1.2 μA of total quiescent current and is designed for a maximum load current of 5 mA. Detailed pole/zero analysis is performed to aid in the design of the LDOs. Two LHP zeros cancel the two non-dominant poles which extend the bandwidth and improve transient response. Both designs are fully integrated, stabilized with an on-chip capacitive load of 100 pF. In load transient, the total variation in output voltage for LI Q -LDO and MI Q -LDO is 1 V and 950 mV, respectively, and the total line transient variation is 668 and 599 mV, respectively. Both designs occupy an area of 0.26 mm2 in a 0.5-μm CMOS process. Two process-independent figures of merit are proposed to compare LI Q -LDO and MI Q -LDO with other published work.  相似文献   
43.
Three Himalayan medicinal plants (Habenaria intermedia, H. edgeworthii, and Roscoea procera), widely used in vitality strengthening Ayurvedic formulations in India, were assessed for nutritional phytochemical constituents, and antioxidant activity. These target species emerged as a good source of minerals and possessed important micro elements. Individually, H. intermedia contained a high content of total phenols, thiamins, tannins, and calcium; R. procera was rich in potassium and iron content; and H. edgeworthii emerged as a good source of sodium. While various antioxidant assays provided evidences on the antioxidant potential of target species, greater antioxidant potential of H. intermedia as compared to the other two species was revealing. This study, therefore, highlighted the possibilities of harnessing nutritional and antioxidant potential of these species.  相似文献   
44.
In the present work, we report the preparation of lanthanum-modified lead zirconate titanate (PLZT) thin films in pure perovskite phase by RF magnetron sputtering. For this purpose, a 3-in. diameter target of PLZT (8/60/40) was prepared by conventional solid-state reaction route. The chemical composition of PLZT target was determined using gravimetric analysis followed by UV–vis and flame atomic absorption spectrometry. Various deposition parameters such as target-to-substrate spacing, deposition temperature, post-deposition annealing temperature and time have been optimized to obtain PLZT films in pure perovskite phase. The films prepared in pure argon at 100 W RF power without external substrate heating exhibited pure perovskite phase after rapid thermal annealing (RTA) as confirmed by X-ray diffraction (XRD). Compositional analysis of the PLZT film was performed by secondary ion mass spectroscopy (SIMS) using PLZT target as standard sample. Depth profile of the film shows very good stoichiometric uniformity of all elements of PLZT.  相似文献   
45.
S. cremoris produced highest growth and amine production in 24 h at 30°C. The optimum pH for the synthesis of histamine, tyramine and tryptamine by S. cremoris was observed at pH 5·5. Maximum production of different amines was obtained in the absence of NaCl. As the rate of incorporation of NaCl in the basal medium was increased beyond 0·5%, the level of amine production was considerably suppressed with concomitant decrease in cell growth.  相似文献   
46.
Approximately 1.5-2.5 μm thick nanocomposite coatings of TiAlCrYN were deposited using a four-cathode reactive unbalanced pulsed direct current magnetron sputtering system from the sputtering of Ti, Al, Cr, and Y targets in Ar + N2 plasma. The TiAlCrYN nanocomposite coatings were deposited on various substrates such as high speed steel (HSS) drill bits, mild steel and silicon. TiAlCrYN coatings with almost similar mechanical properties but with different Ti, Al, Cr and Y contents were prepared to study their thermal stability and machining performance. The structural and mechanical properties of the coatings were characterized using X-ray diffraction and nanoindentation technique, respectively. The elemental composition, bonding structure, surface morphology and cross-sectional data were studied using energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy and field-emission scanning electron microscopy, respectively. Nanoscratch tests were performed to determine the adhesive strength of the coatings. The corrosion behavior of TiAlCrYN nanocomposite coatings on mild steel substrate was studied using potentiodynamic polarization in a 3.5% NaCl solution. Micro-Raman spectroscopy was used to characterize the structural changes as a result of heating of the nanocomposite coatings in air (600-1000 °C). TiAlCrYN coatings prepared at 17 at.% Ti, 13 at.% Al, 21 at.% Cr and 1 at.% Y exhibited thermal stability as high as 900 °C in air (denoted as Sample 3). For the performance evaluation, the TiAlCrYN coated HSS drill bits were tested under accelerated machining conditions. With a drill speed of 800 rpm and a feed rate of 0.08 mm/rev the TiAlCrYN coated HSS drill bits (Sample 3) averaged 657 holes, while drilling a 12 mm thick 304 stainless steel plate under dry conditions, before failure. Whereas, the uncoated drill bits failed after drilling 50 holes under the same machining conditions. Results indicated that for the HSS drill bits coated with TiAlCrYN, the tool life increased by a factor of more than 12.  相似文献   
47.
The synthesis conditions and oxygen stoichiometry were determined using a thermogravimetric analyser. The kinetics of oxygenation at different temperatures and at different atmospheres were studied. The oxygenation kinetics were found to be sensitive to porosity of the material. The appropriate oxygenation temperature was found to be 400 °C. For oxygenation temperatures below 400 °C, the oxygenation occurs by a nucleation and growth process, whereas for higher temperatures it is diffusion limited.  相似文献   
48.
A High Data Rate (HDR) system has been proposed for providing downlink wireless packet service by using a channel-aware scheduling algorithm to transmit to users in a time-division multiplexed manner. In this paper, we propose using multiple antennas at the transmitter and/or at the receiver to improve performance of an HDR system. We consider the design tradeoffs between scheduling and multi-antenna transmission/detection strategies and investigate the average Shannon capacity throughput as a function of the number of antennas assuming ideal channel estimates and rate feedback. The highest capacities are achieved using multiple antennas at both the transmitter and receiver. For such systems, the best performance is achieved using a multi-input multi-output capacity-achieving transmission scheme such as BLAST (Bell Labs Layered Space-Time) in which the transmitted signal is coded in space and time, and the receive antennas are used to resolve the spatial interference. In the second part of the paper, we discuss practical transmitter and receiver architectures using BLAST for approaching the theoretical gains promised by the capacity analysis. Because the terminal receivers will be portable devices with limited computational and battery power, we perform a computational complexity analysis of the receiver and make high-level assessments on its feasibility. We conclude that the overall computational requirements are within the reach of current hardware technology.  相似文献   
49.
Phytol was chemically transformed into fifteen semi‐synthetic derivatives, which were evaluated for their antibacterial and drug resistance reversal potential in combination with nalidixic acid against E. coli strains CA8000 and DH5α. The pivaloyl ( 4 ), 3,4,5‐trimethoxybenzoyl ( 9 ), 2,3‐dichlorobenzoyl ( 10 ), cinnamoyl ( 11 ), and aldehyde ( 14 ) derivatives of phytol ((2E,7R,11R)‐3,7,11,15‐tetramethyl‐2‐hexadecen‐1‐ol) were evaluated by using another antibiotic, tetracycline, against the MDREC‐KG4 clinical isolate of E. coli. Derivative 4 decreased the maximal inhibitory concentration (MIC) of the antibiotics by 16‐fold, while derivatives 9 , 10 , 11 , and 14 reduced MIC values of the antibiotics up to eightfold against the E. coli strains. Derivatives 4 , 9 , 10 , 11 , and 14 inhibited the ATP‐dependent efflux pump; this was also supported by their in silico binding affinity and down‐regulation of the efflux pump gene yojI, which encodes the multidrug ATP‐binding cassette transporter protein. This study supports the possible use of phytol derivatives in the development of cost‐effective antibacterial combinations.  相似文献   
50.
BACKGROUND: The genus Fusarium comprises a diverse group of fungi including several species that produce mycotoxins in food commodities. In the present study, a multiplex PCR was standardised for the group‐specific detection of fumonisin‐producing and trichothecene‐producing strains of Fusarium species. Primers for genus‐level recognition of Fusarium spp. were designed from the internal transcribed spacer regions 1 and 2 of rDNA. Primers for group‐specific detection were designed from the tri5 and tri6 genes involved in trichothecene biosynthesis and the fum1 and fum13 genes involved in fumonisin biosynthesis. RESULTS: Among the various genera and their strains tested, all the 85 confirmed Fusarium strains were positive for rDNA gene and the rest stayed negative. From among the Fusarium strains, 15 had amplification for trichothecene‐ and 20 for fumonisin‐encoding genes. All PCR positive trichothecene chemotypes of Fusarium species tested were positive for chemical analysis but in the case of fumonisins, of the 20 PCR positive cultures, only 13 showed positive for chemical analysis by HPTLC. CONCLUSION: The assay described here provided a rapid and reliable detection of trichothecene‐ and fumonisin‐producing Fusarium directly from natural food grains and the results were always comparable with a conventional HPTLC detection method. It can, therefore, be used by the food industry to monitor quality and safety. Copyright © 2011 Society of Chemical Industry  相似文献   
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