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131.
In order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students. Fifteen (15.3%) of the 98 students were sensitized to SEA and/or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p < 0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p < 0.05), and a negative correlation (p < 0.001) was recognized between the neutrophil and the lymphocyte rates.  相似文献   
132.
The purpose of this study is to investigate the vascular wall with a thermally self-regulating, cylindrical stent made of a low Curie temperature ferromagnetic alloy. Physiologic saline was circulated in the silicone model vessel implanted with the stent. The stent-temperature remained nearly constant for variable saline flows, saline temperatures, and magnetic flux densities. Stent implants of this type in human blood vessels could potentially enable thermotherapy and temperature determination without catheterization.  相似文献   
133.
The demand for effective and inexpensive adsorbents is to increase in response to the widespread recognition of the deleterious health effects of arsenic exposure through drinking water. A novel adsorbent, aluminum-loaded Shirasu-zeolite P1 (Al-SZP1), was prepared and employed for the adsorption and removal of arsenic(V) (As(V)) ion from aqueous system. The process of adsorption follows first-order kinetics and the adsorption behavior is fitted with a Freundlich isotherm. The adsorption of As(V) is slightly dependent on the initial pH over a wide range (3-10). Al-SZP1 was found with a high As(V) adsorption ability, equivalent to that of activated alumina, and seems to be especially suitable for removal of As(V) in low concentration. The addition of arsenite, chloride, nitrate, sulfate, chromate, and acetate ions hardly affected the As(V) adsorption, whereas the coexisting phosphate greatly interfered with the adsorption. The adsorption mechanism is supposed as a ligand-exchange process between As(V) ions and the hydroxide groups present on the surface of Al-SZP1. The adsorbed As(V) ions were desorbed effectively by a 40 mM NaOH solution. Continuous operation was demonstrated in a column packed with Al-SZP1. The feasibility of this technique to practical utilization was also assessed by adsorption/desorption multiple cycles with in situ desorption/regeneration operation.  相似文献   
134.
Two optical methods, cavity ring-down spectroscopy and photoacoustic spectroscopy, are applied to the measurement of the isotope ratio 18O/16O in water-vapor samples with a Nd3+:YAG pumped-dye laser. The combination band of (2v1 + v3) in the 960-nm region of water molecules is investigated for two standard water samples, the Vienna Standard Mean Ocean Water and the Standard Light Antarctic Precipitation. The results demonstrate that the two methods have the potential of compact systems for in-situ measurements of H2O isotope ratio in the environment.  相似文献   
135.
The behaviour of 4 He impurities has been investigated through positive ion mobility measurements in liquid 3 He at milliKelvin temperatures. In spite of the enormous surface area of the cell, the influence of 4 He lasted for hundreds of hours at temperatures of 20 mK. However below 10 mK, the 4 He impurities were quickly frozen out on the cell walls and we were free from the impurity problem. Nevertheless the multiple ion signal occasionally appeared even at a few mK, although it disappeared for a number of ionization pulses.  相似文献   
136.
The anisotropic scattering effect to keff is studied for UO2 and MOX fueled BWR assemblies. The anisotropic scattering effect increases the assembly k by 0.44% Δk for the UO2 assembly with 0% void fraction, and by 0.21% Δk for the MOX assembly with 0% void fraction. This is because the anisotropic scattering effect flattens the intra-assembly thermal flux, and the absorption rate in the surrounding water gap is decreased, but the absorption rates in the MOX fuel rods are increased compared to the UO2 rods. Therefore, the total decrease in absorption rates in the UO2 assembly is relatively large, and the k is increased in the UO2 assembly. The dependence of the anisotropic scattering effect on the void fraction is investigated, and the significant difference of 0.62% Δk/k is found for the 0% and the 80% void fractions. The BWR assemblies with Gd rods are also considered. Furthermore, the usefulness of the transport cross section is investigated, and it is found that the transport cross section gives reasonable anisotropic scattering effect, though not satisfactory.  相似文献   
137.
Abstract— The synthesis of carbon‐nanotube (CNT) field emitters for FEDs by thermal chemical vapor deposition (CVD) and their structural and emission characterization are described. Multi‐walled nanotubes (MWNTs) were grown on patterned metal‐base electrodes by thermal CVD, and the grown CNTs formed a network structured layer covering the surfaces of the metal electrode uniformly, which realized uniform distribution of electron emission. A technique for growing narrow MWNTs was also developed in order to reduce the driving voltage. The diameter of MWNT depends on the growth temperature, and it has changed from 40 nm at the low temperature (675°C) to 10–15 nm at the high temperature (900–1000°C). Moreover, narrower MWNTs were grown by using the metal‐base electrode covered with a thin alumina layer and a metal catalyst layer. Double‐walled nanotubes (DWNTs) were also observed among narrow MWNTs. The emission from the narrow CNTs showed a low turn‐on electric field of 1.5 V/μm at the as‐grown layer.  相似文献   
138.
We present a phrase-based statistical machine translation approach which uses linguistic analysis in the preprocessing phase. The linguistic analysis includes morphological transformation and syntactic transformation. Since the word-order problem is solved using syntactic transformation, there is no reordering in the decoding phase. For morphological transformation, we use hand-crafted transformational rules. For syntactic transformation, we propose a transformational model based on a probabilistic context-free grammar. This model is trained using a bilingual corpus and a broad-coverage parser of the source language. This approach is applicable to language pairs in which the target language is poor in resources. We considered translation from English to Vietnamese and from English to French. Our experiments showed significant BLEU-score improvements in comparison with Pharaoh, a state-of-the-art phrase-based SMT system.  相似文献   
139.
介绍一种具有感觉系统、能够四足步行的仿生人造牲畜。该仿生人造牲畜具有12个自由度,关节采用滑块摆杆机械,由伺服电机驱动,其感觉系统由身体上的姿势传感器、脚上的力传感器以及与伺服电机同轴安装的轴角编码器构成。该仿生人造牲畜的步行由计算机进行控制。  相似文献   
140.
This paper proposes a novel low power dissipation technique for a low voltage OTA. A conventional low power OTA with a class AB input stage is not suitable for a low voltage operation (±1.5 V supply voltages), because it uses composite transistors (referred to CMOS pair) which has a large threshold voltage. On the other hand, the tail-current type OTA needs a large tail-current value to obtain a sufficient input range at the expense of power dissipation. Therefore, the conventional tail-current type OTA has a trade-off between the input range and the power dissipation to the tail-current value. The trade-off can be eliminated by the proposed technique. The technique exploits negative feedback control including a current amplifier and a minimum current selecting circuit. The proposed technique was used on Wang's OTA to create another OTA, named Low Power Wang's OTA. Also, SPICE simulations are used to verify the efficiency of Low Power Wang's OTA. Although the static power of Low Power Wang's OTA is 122 W, it has a sufficient input range, whereas conventional Wang's OTA needs 703 W to obtain a sufficient input range. However, we can say that as the input signal gets larger, the power of Low Power Wang's OTA becomes larger.  相似文献   
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