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91.
This study evaluated a novel use of the traditional Asian herb Anoectochilus formosanus. This plant is a traditional food item, generally used for the treatment of liver disorder, hepatitis, hypertension, diabetes, cardiovascular disorder, etc. In this study, the root, stem, and leaf of A. formosanus were used as substrates for lactic fermentation. The fermentation products were analyzed for their total antioxidant activity, reducing power, and scavenging effect on superoxide anion radicals and hydrogen peroxide. The pH of the fermentation medium reached its lowest value, 3.5, at the 35th hour of fermentation. Antioxidant activity of A. formosanus was found to be 61-78%. Lactobacillus longum-led fermentation exhibited the greatest reducing power with an average of 0.3. The products of fermentations utilizing the three plant parts as substrates exhibited a similar scavenging activity (27-30%) on free radicals. This study may suggest a novel use of lactic-fermenting A. formosanus in the production of functional food.  相似文献   
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Fabrication of micro-electrodes by multi-EDM grinding process   总被引:1,自引:0,他引:1  
In this study, a multi-EDM grinding process is adapted to fabricate micro-electrodes. Equipments such as a wire EDM machine and a traditional CNC-EDM machine are used for machining micro-electrodes. Rod electrodes of copper with diameter 3.0 mm were cut to be 0.15 mm on wire-EDM machine at first step. EDM grinding process was used to grind micro-electrodes to fine diameter bellow 20 μm on a CNC-EDM machine at second step. For EDM grinding, rotating mechanisms are mounted on both the WEDM machine and the CNC-EDM machine. A CCD camera is provided for viewing and for on-line dimensional controlling, when micro-electrodes were cutting. Fine electrodes could be processed to a smaller size using proposed two-steps EDM grinding process. Higher L/D ratio could be also achieved by this method. The processed fine electrodes can be used for drilling micro-holes, micro-deep holes, micro-milling, micro-punching, and manufacturing of micro-nozzles.  相似文献   
95.
This paper presents an experimental investigation of the cyclic responses of thin-walled structural steel members under an earthquake-induced, coupled three-dimensional load. Nine thin-walled structural steel members were tested under various load combinations to investigate the correlation among bending, axial load and torsion. Bending capacities of tested members were compared to distinguish the effects of torsion, axial load and their combination in affecting a member's bending performance. Test results show that members' bending strength is reduced when axial load is applied. Further reduction in member performance is exhibited when coupled torsion and axial load are both present; this reduction demonstrates the necessity for including torsion in calculating a member's bending strength when buildings are designed to be earthquake-resistant.  相似文献   
96.
BACKGROUND: Myricetin is a naturally occurring flavonoid that is found in many fruits, vegetables, teas and medicinal herbs. It has been demonstrated to have anti‐inflammatory properties, but, to date, no studies have described the immunomodulatory effects of myricetin on the functions of dendritic cells (DCs). The aim of this study was to evaluate the potential for myricetin to modulate lipopolysaccharide (LPS)‐stimulated activation of mouse bone marrow‐derived DCs. RESULTS: Our experimental data showed that treatment with myricetin up to 10 µg mL−1 does not cause cytotoxicity in cells. Myricetin significantly decreased the secretion of tumour necrosis factor‐α, interleukin‐6 and interleukin‐12p70 by LPS‐stimulated DCs. The expression of LPS‐induced major histocompatibility class II, CD40 and CD86 on DCs was also inhibited by myricetin, and the endocytic and migratory capacity of LPS‐stimulated DCs was blocked by myricentin. In addition, LPS‐stimulated DC‐elicited allogeneic T‐cell proliferation was reduced by myricetin. Moreover, our results confirmed that myricetin attenuates the responses of LPS‐stimulated activation of DCs via suppression of IκB kinase/nuclear factor‐κB and mitogen‐activated protein kinase‐dependent pathways. CONCLUSION: Myricetin has novel immunopharmacological activity, and modulation of DCs by myricetin may be an attractive strategy for the treatment of inflammatory and autoimmune disorders, and for transplantation. Copyright © 2012 Society of Chemical Industry  相似文献   
97.
In this paper, a sliding-mode speed controller based on a new switching surface is proposed for induction motor systems. With this variable structure control switching surface, the exponential stability is guaranteed for the speed servo control and insensitivity to uncertainties and disturbances are obtained as well. Moreover, an adaptive variable structure speed control is studied to relax the need for the bound of disturbance in variable structure control. The insensitivity or robustness of the proposed method for general speed servo systems is maintained, and the dynamic performances are improved as well. Finally, the validity of proposed scheme is demonstrated by computer simulations and experimentations  相似文献   
98.
Summary The effects of pH (2, 7 and 10), NaCl concentrations (0, 1, 3 and 5% w/w), and temperatures (−20, 25 and 100 °C) on the physical properties of nata, a bacteria cellulose produced by Acetobacter aceti ssp. xylinum , were evaluated in this study. The addition of NaCl was found to increase the hardness of nata but to decrease the water-holding capacity; however, no effect of NaCl on the hardness of nata was found when nata was acidified or alkalized. Compared to the texture properties of nata at 25 °C, freezing at −20 °C for 24 h gave a more elastic texture, but heating at 100 °C for 3 h had no significant effect on the textural properties. The results of this study indicated that acidification or alkalization was necessary to prepare salted nata products without increasing their hardness.  相似文献   
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100.
The polymerization reaction of a bone cement (standard Surgical Simplex-P Radiopaque) upon heating has been investigated by differential scanning calorimetry (DSC). The effects of the addition of tricalcium phosphate (TCP) on the rate and the heat of polymerization during DSC heating were evaluated. The rate and polymerization heat (ΔH) were characterized by the initial curing temperature (Ti), peak temperature (Tp), completing curing temperature (Tf), the curing range (ΔT = Tf ? Ti) and the area of the DSC exotherm. It was found that Ti, Tp, Tf, ΔT, and ΔH all increase with increasing heating rate. Increasing TCP content also induced increases in Ti, Tp, Tf, ΔT, and ΔH. From the kinetic analysis, the polymerization of acrylic bone cement was found to be a first order reaction. The effects of heating rate and TCP contents on the rate and the heat of polymerization could be explained based on the frequency factor and the activation energy extracted from the kinetic analysis. Increases in both heating rate and TCP content depressed the frequency factor and the activation energy.  相似文献   
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