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21.
Kanal+允许VCR记录由STB和TV获取的音频和视频信号,无须改变TV、STB和VCR背板的SCART连接。这里介绍的Kanal+支持功能允许在不改变TV背板连接的条件下,VCR能够Kanal+允许VCR记录由STB和TV获取的音频和视频信号,无须改变TV、STB和VCR背板的SCART连接。这里介绍的Kanal+支持功能允许在不改变TV背板连接的条件下,VCR能够记录由TV获取的音频和视频信号。使用这种方案,TV把音频和视频信号发送回STB;待机模式下,STB再把这些信号发给VCR。  相似文献   
22.
Concentrations of trans-resveratrol, catechin and epicatechin were analyzed in musts and wines produced from seven red and four white grape cultivars from various wine growing regions of Turkey. Phenolics were quantified using an HPLC method optimized for the separation of wine phenolics. Wine samples contained higher phenolics levels than the corresponding musts. With the exception of Semillion, white wines and musts contained lower concentrations of phenolics than red wines and musts. However, the white cultivar Semillion had the highest concentrations of catechin and epicatechin among all wine and must samples. Semillion wine catechin and epicatechin were 13.7 and 11.8 mg/L, respectively. The highest level of trans-resveratrol among the white cultivars was found in Narince wine (1.93 mg/L). Within the red wine and must cultivars, Bo?azkere, Öküzgozü, and Cabernet contained the highest concentrations of flavan-3-ols and trans-resveratrol. Catechin was the major phenolic in all wines and most musts. Epicatechin was the major phenolic in 6 of the 11 must samples, but none of the wine samples. trans-Resveratrol was generally found in lowest concentrations in both wines and musts.  相似文献   
23.
The rate of hydrogen evolution from a photocatalytic process depends not only on the activity of a photocatalyst, but also on photoreactor design. Ideally, a photoreactor should be able to absorb the incident light, promoting photocatalytic reactions in an effective manner with minimal photonic losses. There are numerous technical challenges and cost related issues when designing a large-scale photoreactor for hydrogen production. Active stirring of the photocatalyst slurry within a photoreactor is not practical in large-scale applications due to cost related issues. Rather, the design should allow facile self-mixing of the flow field within the photoreactor. In this paper two types of photocatalytic reactor configurations are studied: a batch type design and another involving passive self-mixing of the photolyte. Results show that energy loss from a properly designed photoreactor is mainly due to reflection losses from the photoreactor window. We describe the interplay between the reaction and the photoreactor design parameters as well as effects on the rate of hydrogen evolution. We found that a passive self-mixing of the photolyte is possible. Furthermore, the use of certain engineering polymer films as photoreactor window materials has the potential for substantial cost savings in large-scale applications, with minimal reduction of photon energy utilization efficiency. Eight window materials were tested and the results indicate that Aclar™ polymer film used as the photoreactor window provides a substantial cost saving over other engineering polymers, especially with respect to fused silica glass at modest hydrogen evolution rates.  相似文献   
24.
Knowledge and Information Systems - This work studies the location-privacy preserving location update in the context of data-centric people mobility applications. The mobility model involves an...  相似文献   
25.
Recent achievements and future opportunities for the design of 2D, 3D, and 4D materials using photochemical reactions are summarized. Light is an attractive stimulus for material design due to its outstanding spatiotemporal control, and its ability to mediate rapid polymerization under moderate reaction temperatures. These features have been significantly enhanced by major advances in light generation/manipulation with light-emitting diodes and optical fiber technologies which now allows for a broad range of cost-effective fabrication protocols. This combination is driving the preparation of sophisticated 2D, 3D, and 4D materials at the nano-, micro-, and macrosize scales. Looking ahead, future challenges and opportunities that will significantly impact the field and help shape the future of light as a versatile and tunable design tool are highlighted.  相似文献   
26.
Background At the University of Michigan, qualified first‐year students who place out of the first‐semester calculus course may enroll in either the regular second‐semester calculus course or Applied Honors Calculus II. Students who enroll in Applied Honors Calculus II show higher academic performance than students enrolling in the Regular Calculus II. Purpose (Hypothesis ) The study addressed the question: does enrollment in Applied Honors Calculus II have a positive causal impact on subsequent academic performance for engineering students at the University of Michigan? Design /Method We acquired seven years of institutional data for engineering students who entered the University of Michigan from 1996 through 2003 and who qualified to enroll in Applied Honors Calculus II. Using regression analyses, we tested a causal model of impact of Applied Honors Calculus II on four measures of subsequent academic performance: grade in Physics II and average grade in all subsequent physics, mathematics, and engineering courses. Results After controlling for students' personal characteristics and prior academic achievement, the impact of Applied Honors Calculus II on students' academic performance was not statistically significant. In particular Advanced Placement scores accounted for the higher performance observed in Applied Honors Calculus II students. Conclusions We recommend including Advanced Placement scores in models that predict academic performance. Future research should also include measures of socioeconomic status (SES) and explore interactions between SES and academic background. Finally, in evaluations of specific curricula, the treatment effect—measured as treatment group mean minus control group mean, after controlling for covariates—is unlikely to be large if the control group receives high quality instruction.  相似文献   
27.
A 35 year old man with a fatal Campylobacter jejuni infection is described. He had HbE/beta zero thalassaemia and had undergone splenectomy nine months previously for hypersplenism; he also had chronic hepatitis C infection. He presented with high grade fever but no gastrointestinal symptoms and rapidly progressed to septicaemic shock and hepatic encephalopathy despite treatment with penicillin, gentamicin, and, later, chloramphenicol and ceftazidime. Only one case of Campylobacter jejuni septicaemia occurring post-splenectomy has been reported previously, also in an iron overloaded thalassaemia patient. Unusual Gram negative bacilli must be covered by the chosen antibiotic regimen when splenectomised thalassaemic patients present with high grade fever.  相似文献   
28.
In this work, density functional theory calculations on the structural, mechanical, lattice dynamical, and thermodynamical properties of YB2 in AlB2-type and monoclinic (C2/m) structures are reported. The local density approximation has been used for modeling exchange–correlation effects. We have predicted the lattice constants, bulk modulus, elastic constants, shear modulus, Young’s modulus, Poison’s ratio, Debye temperature, and sound velocities. Furthermore, the phonon dispersion curves, corresponding phonon density of states, some thermodynamical quantities such as internal energy, entropy, heat capacity, and their temperature-dependent behaviors are presented. Our structural and some other results are in agreement with the available experimental and theoretical data.  相似文献   
29.
Nutritional intake appears to be an important factor contributing to aging. In the present study we describe changes in physical health related to nutritional intake among elderly persons in a 10-y longitudinal study. Among 304 healthy elderly participants (median age 72 y on entry into the study in 1980), 97 (34.2%) are still in good health 10 y later in 1990, 74 (26.5%) have become frail or sick, 54 (19.1%) have died, and 57 (20.1%) have dropped out of the study. Women with lower or higher energy intakes (in 1980 and 1981) than the current Recommended Daily Allowance (RDA; between 25 and 30 kcal/kg) were more likely to become frail or sick or to die in 1990 than those with energy intake in the midrange (below RDA, odds ratio (OR) = 3.3, confidence interval (CI) = 1.2-8.6; above RDA, OR = 3.4, CI: 1.1-10.7). Moreover, women with protein intakes greater than the midrange of 0.8-1.2 g/kg of body weight (1.20-1.76 g/kg in 1980 and 1981) tended to have fewer health problems over the next 10 y than those with protein intakes < 0.8 g/kg, suggesting that the mean protein requirement in elderly adults is greater than that established by the 1985 joint World Health Organization/ FAO/UNU Expert Committee. Moreover, a decrease in energy intake was greater in elderly persons who died or dropped out of the study because of illness.  相似文献   
30.
A retrospective clinical trial was performed to review the management and discuss the outcome of cataract extraction in eyes with complicated cataract due to ocular Beh?et's disease (BD) (n = 55) and idiopathic uveitis (IU) (n = 43). The aim was to find the best method of treatment in each pathology. The surgical methods were intracapsular cataract extraction (ICCE), extracapsular cataract extraction (ECCE), ECCE + intraocular lens (ECCE + IOL), and ECCE + trabeculectomy (ECCE + T). The postoperative visual prognosis was found to be significantly worse in eyes with ocular BD, than in those with IU because of the severe posterior segment complications of ocular BD, particularly optic atrophy (p < 0.05). When the outcome was evaluated with regard to the individual surgical techniques, the prognosis was found to be significantly better in eyes with IU undergoing ECCE than in those with BD undergoing the same operation (p < 0.05). No significant differences were observed between the groups with regard to the other surgical treatment modalities (p < 0.05).  相似文献   
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