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991.
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

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992.
993.
Regioregular poly(3-hexylthiophene) has been successfully incorporated into various poly(N,N-dimethylamino-2-ethyl methacrylate)-based block copolymers, i.e., P3HT-b-PDMAEMA, via Grignard metathesis (GRIM) method and atom transfer radical polymerization (ATRP) reactions. The structure of the diblock copolymers was fully confirmed by FT-IR, 1H NMR spectroscopy, gel permeation chromatography (GPC), and ultraviolet–visible spectroscopy (UV–vis). The recovered copolymers could be treated by protonation of the pending tertiary amine functions and depending on the relative content in PDMAEMA, the copolymers could be solubilized in more polar solvents where P3HT alone proved to be totally insoluble.  相似文献   
994.
We built new hybrid devices consisting of chemical vapor deposition (CVD) grown carbon nanotube (CNT) transistors, decorated with TbPc(2) (Pc = phthalocyanine) rare-earth based single-molecule magnets (SMMs). The drafting was achieved by tailoring supramolecular π-π interactions between CNTs and SMMs. The magnetoresistance hysteresis loop measurements revealed steep steps, which we can relate to the magnetization reversal of individual SMMs. Indeed, we established that the electronic transport properties of these devices depend strongly on the relative magnetization orientations of the grafted SMMs. The SMMs are playing the role of localized spin polarizer and analyzer on the CNT electronic conducting channel. As a result, we measured magneto-resistance ratios up to several hundred percent. We used this spin valve effect to confirm the strong uniaxial anisotropy and the superparamagnetic blocking temperature (T(B) ~ 1 K) of isolated TbPc(2) SMMs. For the first time, the strength of exchange interaction between the different SMMs of the molecular spin valve geometry could be determined. Our results introduce a new design for operable molecular spintronic devices using the quantum effects of individual SMMs.  相似文献   
995.
By using mixing intensification involving high solids concentration as a means to achieve process intensification for the mineral process industry is discussed here. Improving agitator energy efficiency is essential for operating at high solids concentrations. It is shown that improved agitator energy efficiency can be achieved by removing baffles and using higher power number impellers at high solids loadings. Power consumption (50–80%) reductions were demonstrated in the experiments. It is also suggested that slurry stratification in tanks can be used to boost either solids residence time or slurry mass flow. Basic equations related to solids residence time and solids throughput are presented for guidance toward minerals process intensification. An example on doubling throughput via intensification is presented. © 2010 American Institute of Chemical Engineers AIChE J, 2011  相似文献   
996.
Cr2AlC compounds were synthesized by a powder metallurgical route and corrosion tested at 900, 1000, 1100 and 1200 °C for up to 150 h under an Ar/1% SO2 gas atmosphere. The compounds were resistant to corrosion because a thin ??-Al2O3 barrier layer quickly formed on the surface which suppressed sulfidation. Virtually no sulfur was detected inside the scale except during the initial corrosion stage. The superior corrosion resistance of Cr2AlC originated from the high affinity of Al for oxygen to form the thermodynamically stable Al2O3. Unlike Al, Cr was not active because Cr was strongly bound to carbon as Cr2C layers in Cr2AlC. The small amount of Cr2O3 that had formed was dissolved in the Al2O3 layer. The corrosion of Cr2AlC resulted in the formation of an ??-Al2O3 layer and an underlying Cr7C3 layer.  相似文献   
997.
Nguyen TD  Dinh CT  Do TO 《Nanoscale》2011,3(4):1861-1873
A conventional and general route has been exploited to the high yield synthesis of many kinds of highly crystalline metal oxide and mixed oxide nanocrystals with different morphologies including belt, rod, truncated-octahedron, cubic, sphere, sheet via the hydrothermal reaction of inorganic precursors in aqueous solution in the presence of bifunctional 6-aminohexanoic acid (AHA) molecules as a capping agent. This method is a simple, reproducible and general route for the preparation of a variety of high-crystalline inorganic nanocrystals in scale-up. The shape of inorganic nanocrystals such as CoWO(4), La(2)(MoO(4))(3) can be controlled by simply adjusting the synthesis conditions including pH solution and reaction temperature. Further, by tuning precursor monomer concentration, the mesocrystal hierarchical aggregated microspheres (e.g., MnWO(4), La(2)(MoO(4))(3)) can be achieved, due to the spontaneous assembly of individual AHA-capped nanoparticles. These obtained AHA-capped nanocrystals are excellent supports for the synthesis of a variety of hybrid metal/oxide nanocrystals in which noble metal particles are uniformly deposited on the surface of each individual nanosupport. The photocatalytic activity of Ag/TiO(2) nanobelts as a typical hybrid photocatalyst sample for Methylene Blue degradation was also studied.  相似文献   
998.
Thin films of FeCoHfN were fabricated by co-sputtering technique with the deposition angles varied. Their dynamic magnetic properties were characterized and discussed in conjunction with an analysis based on Landau-Lifshitz-Gilbert equation. High ferromagnetic resonance frequency beyond 6 GHz was achieved by adjusting the deposition angle. A discrepancy between static and magnetic anisotropy was observed and discussed within the framework of Hoffmann's ripple theory. Also, the variations of frequency linewidth, damping factor, and permeability with the change of deposition angle were presented and discussed.  相似文献   
999.
The citrus pock caterpillar, Prays endocarpa (Yponomeutidae; Praydinae), is a pest of pomelo (Citrus grandis L.) in Vietnam. Gas chromatography-mass spectrometry analyses of pheromone gland extracts from female moths identified three monoenyl compounds, (Z)-7-tetradecenal (Z7-14:Ald), (Z)-7-tetradecenyl acetate (tentatively identified, Z7-14:OAc), and (Z)-7-tetradecen-1-ol (Z7-14:OH), in a ratio of about 10:3:10. In the field, traps baited with synthetic Z7-14:Ald (0.5 mg) caught male P. endocarpa. The other two compounds, either alone or when added to Z7-14:Ald, did not elicit increases in trap catch (relative to the appropriate treatment). Synthetic Z7-14:Ald was used to monitor and control this species in pomelo orchards in Vinh Long Province. Monitoring revealed that adults were present throughout the year with discernible peaks in December, March, and April. A mass-trapping trial, using 20 traps in a 0.1 ha pomelo orchard, effectively suppressed fruit damage to levels similar to that achieved by an insecticide (Karate 2.5EC). Mating disruption trials, using polyethylene-tube dispensers, each filled with 80 mg of Z7-14:Ald at a rate of 200 or 400 dispensers/ha, also controlled damage by this pest to levels below that achieved by an insecticide treatment. This work demonstrates the potential for pheromone-based control of this pest in Vietnam.  相似文献   
1000.
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