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11.
Excess amounts of redox stress and failure to regulate homeostatic levels of reactive species are associated with several skin pathophysiologic conditions. Nonmalignant cells are assumed to cope better with higher reactive oxygen and nitrogen species (RONS) levels. However, the effect of periodic stress on this balance has not been investigated in fibroblasts in the field of plasma medicine. In this study, we aimed to investigate intrinsic changes with respect to cellular proliferation, cell cycle, and ability to neutralize the redox stress inside fibroblast cells following periodic redox stress in vitro. Soft jet plasma with air as feeding gas was used to generate plasma-activated medium (PAM) for inducing redox stress conditions. We assessed cellular viability, energetics, and cell cycle machinery under oxidative stress conditions at weeks 3, 6, 9, and 12. Fibroblasts retained their usual physiological properties until 6 weeks. Fibroblasts failed to overcome the redox stress induced by periodic PAM exposure after 6 weeks, indicating its threshold potential. Periodic stress above the threshold level led to alterations in fibroblast cellular processes. These include consistent increases in apoptosis, while RONS accumulation and cell cycle arrest were observed at the final stages. Currently, the use of NTP in clinical settings is limited due to a lack of knowledge about fibroblasts’ behavior in wound healing, scar formation, and other fibrotic disorders. Understanding fibroblasts’ physiology could help to utilize nonthermal plasma in redox-related skin diseases. Furthermore, these results provide new information about the threshold capacity of fibroblasts and an insight into the adaptation mechanism against periodic oxidative stress conditions in fibroblasts.  相似文献   
12.
A fibre‐enriched, reduced‐calorie biscuit [formulated biscuit (FB)] was evaluated for its antidiabetic and antilipidaemic potential in streptozotocin‐induced diabetes in Wistar rats against control biscuit (CB) having high calorie and low fibre content. Animals were allocated into five groups: a control group fed with synthetic diet, two diabetes‐induced groups (CBD and FBD) and two nondiabetic groups (CBND and FBND). CBD and CBND were fed with synthetic diet + CB while FBD and FBND were fed with synthetic diet + FB. After 6 weeks of feeding, the change in weight of nondiabetic group fed with FB (+16.20%) was nonsignificantly lower compared to control (+33.01%) and CB‐fed (+34.55%) group. Nonsignificant loss in body weight was observed among diabetic group fed with FB (?11.76%) or CB (?36.88%). Feeding of FB led to a significant decrease in fasting and postprandial blood glucose levels, total cholesterol, triglycerides, LDL‐C, VLDL‐C and atherosclerotic index and increase the HDL‐C. Histological examination showed that feeding of FB was able to partially recover the destroyed β‐cell in STZ‐induced diabetic rats.  相似文献   
13.
In this paper, a new differential input CMOS transconductor circuit for VHF filtering application is introduced. The new circuit has a very high frequency bandwidth, large linear differential mode input range and good common mode signal rejection capability. Using 0.35 m CMOS technology with 3 V power supply, the transconductor has a ±0.9 V linear differential input range with a –54 dB total harmonic distortion (THD) and more than 1 GHz – 3 dB bandwidth. The large signal DC analysis and small signal ac analysis derived by compact equations are in line with SpectreS simulation. A 3rd order elliptic low pass g m-C filter with a cutoff frequency of 150 MHz is demonstrated as an application of the new transconductor.  相似文献   
14.
Millimeter-wave (mm-wave) bandpass filters are presented using the standard 0.18-mum CMOS process. Without any postprocessing steps, thin film microstrip (TFMS) structure is properly constructed on the low-resistivity silicon substrate, aiming at reducing the substrate loss and crosstalk to a large extent. Using the broadside-coupled scheme, a tight coupling is achieved so as to make up a class of low-loss and broadband TFMS bandpass filters in the mm-wave range. To achieve a small size, one-stage and two-stage filters with sinuous-shaped resonators are designed and fabricated. A good agreement between the predicted and measured results has been observed up to 110 GHz  相似文献   
15.
Sun  S. Shi  J. Zhu  L. Rustagi  S.C. Kang  K. Mouthaan  K. 《Electronics letters》2007,43(25):1433-1434
Presented is a compact millimetre-wave bandpass filter using a thin-film microstrip meander line on standard 0.18 mum CMOS silicon substrate without any post-processing step yet still reducing the substrate loss and crosstalk to a large extent. To miniaturize overall circuit size, a half-wavelength resonator is constructed in meander-line configuration and its resonant frequency is designed to be 40 GHz. The prototype single-resonator bandpass filter occupies a circuit area of 210 times 210 mum on silicon. Measured insertion loss is 2.5 dB, which agrees well with the design value in the simulations.  相似文献   
16.
A computer program has been developed to exploit the multimedia capabilities of a personal computer for a new design of sodar (sonic detection and ranging) data acquisition and control system with minimized hardware elements. Advantages include trouble-free, cost-effective and user-friendly sodar data acquisition using any standard computer. The new design overcomes limitations due to using an add-on data acquisition card with conventional computer-controlled sodar. The data can be processed to produce online display of the dynamics of prevailing atmospheric boundary layer thermal structures and inversion/mixing depth for environmental applications.  相似文献   
17.
Chemical oxidative polymerization of aniline using peroxydisulfate oxidant in aqueous pH 2.5–10.0 buffers yields electrically insulating brown powders that are believed to be mixtures of Michael-type adducts of benzoquinone monoimine and aniline at various stages of hydrolysis. A spectroscopically similar product is formed when solid 1,4-benzoquinone is added to an aqueous solution of aniline at room temperature in the absence of peroxydisulfate. This suggests that the peroxydisulfate oxidant in the aniline/S2O82? system provides a pathway for the formation of benzoquinone monoimine as an intermediate. Benzoquinone monoimine intermediate could be formed as a result of a Boyland–Sims rearrangement of aniline proceeding via the intermediacy of p-aminophenyl sulfate. Benzoquinone monoimine undergoes a series of conjugate 1,4-Michael-type addition/reoxidation/coupling steps with aniline or p-aminophenyl sulfate yielding the oligoaniline product. The precipitate that is isolated is also in the midst of two simultaneous pH dependent hydrolysis reactions: (i) hydrolysis of the imine groups to quinone, and (ii) hydrolysis of arylsulfates to phenols. The ratio of hydrolysis in each case was determined by the C/N ratio and sulfur elemental analysis values yielding analytical data that is consistent with experimentally determined values and also with our proposed reaction scheme. These findings offer a rationale for the high C/N ratios (>6.0) frequently observed in these systems while tracing the genesis of the residual sulfur in the product to unhydrolyzed arylsulfate. The oligoaniline product has previously been reported to have a novel poly-aza structure consisting of continuously linked –N–N–N– bonds, and alternately also reported to consist of phenazine-type linkages. This study is consistent with the latter and describes a pathway to phenazine coupling through a second and third stage hydrolysis of the arylsulfate and reoxidation with peroxydisulfate. There is no pathway for the formation of linear –N–N–N– linkages in the aniline/benzoquinone adduct and the striking similarity between its spectroscopic properties and the aniline/S2O82? adduct suggests that it is not a preferred pathway under these experimental conditions.  相似文献   
18.
Bulletin of Engineering Geology and the Environment - The present study identified groundwater depletion–induced land subsidence by spaceborne differential interferometric SAR (DInSAR)...  相似文献   
19.
Artificially soiled test fabrics are widely used to study the cleaning performance of detergents formulations. In this study, artificial soiled cotton test fabrics were prepared in the laboratory using carbon black as a model soil. Design of experiments was used to optimise the concentration of detergent ingredients for stain removal. A multi‐factorial analysis of variance was used to model the effect of sodium dodecylbenzene sulfonate, nonylphenol ethoxylate, sodium silicate, sodium citrate and sodium carbonate as builders on soil removal. A colourimetric evaluation using the CIELAB system was used to measure soil removal. In general, performance increases with increasing concentration of surfactant, silicate and soda ash.  相似文献   
20.
Polymersomes are vesicles whose membranes are comprised of self-assembled block co-polymers. We recently showed that co-encapsulating conjugated multi-porphyrin dyes in a polymersome membrane with ferritin protein in the aqueous lumen confers photo-lability to the polymersome. In the present study, we illustrate that the photo-lability can be extended to vesicles containing dextran, an inert and inexpensive polysaccharide, as the luminal solute. Here we explore how structural features of the polymersome/porphyrin/dextran composite affect its photo-response. Increasing dextran molecular weight, decreasing block copolymer molecular weight, and altering fluorophore-membrane interactions results in increasing the photo-responsiveness of the polymersomes. Amphiphilic interactions of the luminal encapsulant with the membrane coupled with localized heat production in the hydrophobic bilayer likely cause differential thermal expansion in the membrane and the subsequent membrane rupture. This study suggests a general approach to impart photo-responsiveness to any biomimetic vesicle system without chemical modification, as well as a simple, bio-inert method for constructing photo-sensitive carriers for controlled release of encapsulants.  相似文献   
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