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121.
Poly(vinyl chloride)/poly(ethyl methacrylate)-based polymer blend electrolytes comprising propylene carbonate as a plasticizer and a lithium salt LiX (X = BF4, ClO4, CF3SO3) are prepared by a solvent casting technique. The electrolytes are subjected to characterization by ionic conductivity, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetic/differential thermal analysis. The electrolytes that contain LiBF4 exhibit maximum conductivity and are thermally stable up to 254 °C.  相似文献   
122.
Microprocessor controlled transdermal delivery of anticancer drugs 5-Fluorouracil (5-FU) and 6-Mercaptopurine (6-MP) was developed and in vitro evaluation was done. Drugs were loaded based on the pharmacokinetics parameters. In vitro diffusion studies were carried at different current density (0.0, 0.1, 0.22, 0.50 mA/cm2). The patches were evaluated for the drug content, thickness, weight, folding endurance, flatness, thumb tack test and adhesive properties all were well with in the specification of transdermal patches with elegant and transparent in appearance. In vitro permeation studies through human cadaver skin showed, passive delivery (0.0 mA/cm2) of 6-MP was low. As the current density was progressively increased, the flux also increased. the flux also increased with 0.1 mA/cm2 for 15–20 min, but it was less than desired flux, 0.2 mA/cm2 for 30 min showed better flux than 0.1 mA/cm2 current, but lag time was more than 4 h, 0.5 mA/cm2 current for more than 1 h, flux was >159 µg/cm2 h which was desired flux for 6-MP. 5-FU flux reached the minimum effective concentration (MEC) of 54 μg/cm2 h with 0.5 mA/cm2 current for 30–45 min, drug concentration were within the therapeutic window in post-current phase. We concluded from Ohm’s Law that as the resistance decreases, current increases. Skin resistance decrease with increase in time and current, increase in the drug permeation. Interestingly, for all investigated current densities, as soon as the current was switched off, 5-FU and 6-MP flux decreased fairly, but the controlled drug delivery can be achieved by switching the current for required period of time.  相似文献   
123.
The problem of plane strain deformation in an orthotropic micropolar generalized thermoelastic half-space subjected to an arbitrary point heat source is solved. Closed-form solutions for spatial distributions of displacements, stresses, and temperature are derived by using the Fourier transform. A numerical inversion technique has been applied to obtain the solution in the physical domain. Numerical results are obtained and presented graphically along with a comparison of the ones for concentrated and distributed, as well as mechanical and thermal, sources.  相似文献   
124.
125.
The research reported in this paper is concerned with gaining a better understanding of human factors issues in machining and the automation of manufacturing tasks. Mismatches between operators' performance and the requirements of machining tasks were experimentally studied with respect to the relationships with various human characteristics, including skill, age, work experience, self-confidence and trust. Twelve hypotheses concerning interrelationships between these characteristics were evaluated and important relationships established. It is considered that this increased knowledge of the rate of mismatches and an understanding of the causes is essential for the successful design of new working environments, machines and tasks. Much of this change to the working environment is likely to involve some degree of automation of the operators' tasks and so a second and important aspect of the study was designed to establish the extent to which preferred levels of automation were related to the same human characteristics. Four further hypotheses relating preferred levels of automation to skill, age, work experience, self-confidence and trust were tested with results that, in some cases, were unexpected and in others contradict the findings of previous research.  相似文献   
126.
Little is known about the effect of vitamin E on brain function. Therefore, in this study we evaluated the effect of tocotrienol rich fraction (TRF) on behavioral impairment and oxidative stress in aged rats. Thirty-six male Wistar rats (young: 3-months-old; aged: 21-months-old) were treated with either the control (olive oil) or TRF (200 mg/kg) for 3 months. Behavioral studies were performed using the open field test and Morris water maze (MWM) task. Blood was taken for assessment of DNA damage, plasma malondialdehyde (MDA) and vitamin E, and erythrocyte antioxidant enzyme activity. Brains were also collected to measure vitamin E levels. Results showed that aged rats exhibited reduced exploratory activity, enhanced anxiety and decreased spatial learning and memory compared with young rats. DNA damage and plasma MDA were increased, and vitamin E levels in plasma and brain were reduced in aged rats. Aged rats supplemented with TRF showed a markedly reduced level of anxiety, improved spatial learning and memory, reduced amount and severity of DNA damage, a reduced level of MDA, and increased levels of antioxidant enzyme activity and plasma/brain vitamin E compared with age-matched controls. In conclusion, TRF supplementation reverses spatial learning and memory decline and decreases oxidative stress in aged rats.  相似文献   
127.
The ability to manufacture a product using different metal combinations greatly increases flexibility in design and production. Joining of dissimilar metal combinations like Copper-to-Stainless Steel (Cu-to-SS) is, however, a challenging task owing to the large differences in physical and chemical properties. The application of electromagnetic (EM) impact technique is demonstrated for welding copper (Cu) to stainless steel (SS) sheets. The welding Cu-to-SS is accomplished by using Al drivers to accelerate Cu and SS work sheets. The tensile shear strength test and the metallographic studies are carried out for Cu-to-SS EM welds.  相似文献   
128.
The aim of the study was to evaluate the impact of environmental contaminants on oxidative stress biomarkers in hepatocytes of Indian estuarine water grey mullet, Mugil cephalus collected from unpolluted Kovalam and polluted Ennore estuaries. Initially, a comparison was made between the general water chemistry and environmental pollutants like heavy metals to identify the ecotype of the estuaries. Biomarker responses and bioaccumulation of metals were determined along with histological studies of fish hepatocytes to assess contamination impact. Water chemistry data with higher temperature, salinity, pH, biochemical oxygen demand, chemical oxygen demand and low dissolved oxygen and environmental pollutants with higher metal concentration (p < 0.05) were observed at Ennore than Kovalam indicating its polluted environment. A significant increase (p < 0.05) in lipid and protein oxidation markers, decrease (p < 0.05) in thiol status and antioxidant enzyme activities were observed in the Ennore fish hepatocytes compared to Kovalam counterpart. Bioaccumulation of heavy metals was significantly higher (p < 0.05) in fish from Ennore. Hepatocytes from Ennore also featured extensive lipid-type vacuolation, increased size and membrane disruption. All the findings highlighted the value of oxidative stress biomarkers and membrane disruption as the sensitive parameters of environmental pollutant contamination and their importance in biomonitoring of aquatic ecosystems. This is also the first such attempt reported at the cellular level from South India stressing the importance of biomarkers in biomonitoring programmes using fish hepatocytes as the model system.  相似文献   
129.
Objective: To estimate the prevalence and the socioeconomic and demographic correlates of tobacco consumption in India.

Design: Cross sectional, nationally representative population based household survey.

Subjects: 315 598 individuals 15 years or older from 91 196 households were sampled in National Family Health Survey-2 (1998–99). Data on tobacco consumption were elicited from household informants.

Measures and methods: Prevalence of current smoking and current chewing of tobacco were used as outcome measures. Simple and two way cross tabulations and multivariate logistic regression analysis were the main analytical methods.

Results: Thirty per cent of the population 15 years or older—47% men and 14% of women—either smoked or chewed tobacco, which translates to almost 195 million people—154 million men and 41million women in India. However, the prevalence may be underestimated by almost 11% and 1.5% for chewing tobacco among men and women, respectively, and by 5% and 0.5% for smoking among men and women, respectively, because of use of household informants. Tobacco consumption was significantly higher in poor, less educated, scheduled castes and scheduled tribe populations. The prevalence of tobacco consumption increased up to the age of 50 years and then levelled or declined. The prevalence of smoking and chewing also varied widely between different states and had a strong association with individual's sociocultural characteristics.

Conclusion: The findings of the study highlight that an agenda to improve health outcomes among the poor in India must include effective interventions to control tobacco use. Failure to do so would most likely result in doubling the burden of diseases—both communicable and non-communicable—among India's teeming poor. There is a need for periodical surveys using more consistent definitions of tobacco use and eliciting information on different types of tobacco consumed. The study also suggests a need to adjust the prevalence estimates based on household informants

  相似文献   
130.
In the present study, skill of an extended range forecast system has been evaluated for identifying droughts over central India 20-days in advance. Rainfall forecasts from 44 ensemble members of the forecast system developed Indian Institute of Tropical Meteorology (IITM), Pune have been used to prepare probabilistic rainfall forecasts. It is seen that the uncertainties in the forecasts (in terms of ensemble spread) increases from day-5 to day 20. As the focus of the study is for drought predictions, forecasts in the bins 0-5 mm/5 day and 5-25 mm/5 day (no rain or less rain) were studied in detail. It is found that the modeling system has a tendency to over-forecast rainfall probabilities. With bias correction, the forecasts become more reliable. Various drought indices were computed using the mean of the forecast distribution up to 20-days in advance. Standardized precipitation index (SPI) computed using Gamma and Pearson type-III distributions are similar in the study region. It was found that these are in reasonable agreement with those from observations. Probabilistic forecasts of standardized precipitation index (SPI) were made and the relative operating characteristics (ROC) scores indicate that the forecasted SPI values are suitable for application.  相似文献   
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