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1.
Elucidation of the structure of naturally existing or synthesized substances is an important criterion in the study of materials to predict the application of the substance. In this study, polylactide was doped with nano-aluminium oxide and nano-cupric oxide with 1 and 3 mg of concentration variants. The interaction between the polymer matrix and the nanoparticles has been studied using Fourier transform infrared. Successful doping of the polymer has been observed. Attention has been drawn to check the intermolecular bonding in films having varying thicknesses, films prepared at higher sonication temperatures, and chemical homogeneity of the doped polymer films.  相似文献   
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A low-power low-voltage analog signal processing circuit has been designed, fabricated, and tested. The circuit is capable of processing an analog sensor current and producing an ASK modulated digital signal with modulating signal frequency proportional to the sensor current level. An on-chip regulator has been included to stabilize the supply voltage received from an external RF power source. The circuit can operate with a power supply as low as 1 V and consumes only about 20 μW of power, which is therefore very suitable for implantable biomedical applications. The whole chip was laid out and fabricated in a 0.35 μm bulk CMOS technology. Experimental results show good agreement with the simulation results.  相似文献   
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A model has been introduced for a polycrystalline thin film silicon p-n junction solar cell with preferential doping along the grain boundaries. Detailed numerical calculations have been done for the effect of doping depths along the grain boundaries, for different grain sizes, on the performance of the cell under AM1 conditions. The results indicate that preferential doping of grain boundaries leads to significant improvement of the cell performance.  相似文献   
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Based on a multiscale model for fabric materials, dynamic simulations of the fabric ballistic performance were implemented. Through parameter research, it was found that the ballistic performance and mechanical behavior of the fabric materials are determined by a combination of factors and conditions rather than by the material properties alone. The material mechanical properties reflect the inherent strength of the fabric; the fabric weaving structure, boundary conditions, material orientation, and projectile shape also play important roles and have a significant influence on the ballistic performance of the fabric. The multiscale material model incorporates not only the membrane‐like properties of the fabric but also the underlying weaving structure, yarn interaction, and yarn composition. The simulations results show good agreement with the experimental data. Various physical phenomena can be observed in the simulations, such as yarn decrimping, material anisotropy, and two types of damage modes. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Two studies were conducted during which 23 patients with chronic migraine were exposed to pulsing electromagnetic fields over the inner thigh. In an open study, 11 subjects kept a 2-week headache log before and after 2 to 3 weeks of exposure to pulsing electromagnetic fields for 1 hour per day, 5 days per week. The number of headaches per week decreased from 4.03 during the baseline period to 0.43 during the initial 2-week follow-up period and to 0.14 during the extended follow-up which averaged 8.1 months. In a double-blind study, 9 subjects kept a 3-week log of headache activity and were randomly assigned to receive 2 weeks of real or placebo pulsing electromagnetic field exposures as described above. They were subsequently switched to 2 weeks of the other mode, after which they kept a final 3-week log. Three additional subjects in the blind study inadvertently received half-power pulsing electromagnetic field exposures. The 6 subjects exposed to the actual device first showed a change in headache activity from 3.32 per week to 0.58 per week. The 3 subjects exposed to only half the dose showed no change in headache activity. Large controlled studies should be performed to determine whether this intervention is actually effective.  相似文献   
7.
Using previously reported methods of sample preparation an essence of garden cress was obtained which proved to contain only 11 components. Eight have been identified, all glucosinolate degradation products (isothiocyanates and nitriles), and provide over 95% of the sample. Benzyl derivatives, from glucotropaeolin, are the most abundant. No thiocyanates were obtained.  相似文献   
8.
Using previously reported methods of sample preparation an essence of coriander leaf was obtained which proved to contain over 25 components. Most of these have been identified, with aliphatic aldehydes providing nearly 90% of the sample. C12 aldehydes are the most abundant.  相似文献   
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Processing of maize (Zea mays L fresh and dry) for the production of various traditional products results in the loss of phytic acid. Fresh mature corn contains less phytic acid (1·71 g kg?1) than dry corn (7·15–7.60 g kg?1). The loss of phytic acid varies from 18·1 to 46·7% for fresh maize and from 11·5 to 52·6% for dry maize respectively among the heat treatments given. From a nutritional viewpoint, consumption of maize as chapati and after roasting in a sand bath or on charcoal will improve the availability of minerals.  相似文献   
10.
Garlic is a popular spice added to several edible preparations and is a remedy for a variety of ailments. Epidemeological as well as laboratory studies have shown that garlic consumption reduces certain cancer incidences in the stomach, colon, mammary, cervical, etc. This article focuses on the general chemistry, metabolism, anticarcinogenic properties, mechanism of action behind the anticarcinogenic effects, functional foods based on garlic; and future areas of research. Garlic has been shown to metabolized into N-aceryl-S-allyl cysteine, allyl mercaptan, diallyl disulfide, diallyl sulfide, diallyl sulfoxide, diallyl sulfone, and allyl methyl sulfide. Garlic has been thought to bring about its anticarcinogenic effect through a number of mechanisms, such as the scavenging of radicals, increasing gluathione levels, increasing the activities of enzymes such as glutathione S-transferase, catalase, inhibition of cytochrome p4502E1, DNA repair mechanisms, prevention of chromosomal damage etc. Future research should standardize the dosage of garlic and type, ie., whether it should be taken fresh, cooked, or aged. The formulation of odorless functional foods with the retention of anticarcinogenic activity should be further studied.  相似文献   
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