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31.
This study was undertaken to determine the effect of dietary supplementation of sunflower seed in cows on the chemical composition of milk and dairy products. Cream, butter and butter oil were prepared from milk produced by cows fed a control diet (control products) or diet supplemented with 11.2% sunflour seed (CLA-rich products). Milk samples collected were determined for lactose. A sample of CLA-rich or control product was determined for fatty acid profile as well as fat, protein and ash contents. The index of atherogenicity (IA) and the index of thrombogenicity (IT) were also calculated. Results revealed that there was no effect of the inclusion of sunflower seed in the diet on the lactose content in milk and total fat, protein and ash contents in the dairy products. Average contents of conjugated linoleic acid (CLA) and transvaccenic acid (TVA), expressed as g/100g total fatty acid were 0.54 and 1.6, respectively in the control products, and 2 and 6.4, respectively in the CLA-rich products. The content of either CLA or TVA was approximately four fold higher in the latter products. Moreover, CLA-rich products showed considerably low IA and IT, which were, respectively, 38.4 and 25.0% less than those from control products. Fatty acid profiles were unaffected during processing, which demonstrates that CLA is a stable component in the dairy products analyzed. It was concluded that dietary supplementation of sunflower seed in cows increases the CLA and TVA contents in milk, which may contribute to the reduction of the risk of cardiovascular diseases in humans.  相似文献   
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The kojibiose phosphorylase (KP) gene and trehalose phosphorylase (TP) gene from Thermoanaerobacter brockii ATCC35047 were intracellularly hyper-expressed under the control of the Bacillus amyloliquefaciens alpha-amylase promoter in Bacillus subtilis. The production yields were estimated to be 2.1 g of KP and 4.9 g of TP per liter of medium. Selaginose, non-reducing trisaccharide, was synthesized from trehalose utilizing the recombinant KP and TP from B. subtilis. Selaginose was not hydrolyzed by salivary amylase, artificial gastric juice, pancreatic amylase, or small intestinal enzymes.  相似文献   
34.
Oleic acid esters of phytosterols (PSs) and triterpene alcohols (TAs), derived from rice bran, were synthesized using lipases under mild conditions. Some lipases, especially from Candida rugosa, type VII, showed very high substrate specificity towards both PSs and TAs, when a mixture of PS and TA (PS/TA mixture) was used as the substrate source. The maximum yield of PS esters was ca. 80 % in each case; however, the maximum yield of TA esters was much lower when the reaction was continued for 7 days. Due to the difficulty in purifying the esters obtained when the PS/TA mixture was used as source of substrate, free PSs and TAs were separated from the PS/TA mixture by silica-gel and reverse-phase chromatography prior to esterification. The pure PSs or TAs were esterified with oleic acid to obtain the corresponding esters with high purity. Differential scanning calorimetric analysis of the resulting esters revealed that their melting points ranged from 7.0 to 42 °C. These values were at least 100 °C lower than those of the free PSs and TAs.  相似文献   
35.
AC module technology has become popular and a number of AC module types are commercially available. Although their specifications are clear, it seems that their technological meaning has not yet been well developed. Therefore, the authors tried to create the total concepts of PV systems composed of AC modules. They are abbreviated AC module-composed PV system or ACM-PV. In the paper, the possible structural configurations of simple AC modules and battery integrated ones are classified in principle. System categories are also classified to show their total concept. Necessary electrical terminals and interfaces, voltage matching method between inverter and PV part, and AC module testing methods are also discussed.  相似文献   
36.
With the increasing speed of computers and communication links, and the successful convergence of both fields, computers connected by high speed links now represent an enormously large distributed computing system. At the same time, communication between man and machine is also becoming more diverse and personalized. Networking issues such as evolution of user services, seamless communication between hosts, failure recovery and integration of new technologies arise daily. Problem-specific approaches and corresponding solutions are available at considerable cost. However, a common requirement is adaptability of the computer network to a variety of changes. In this paper, we propose Flexible Computer Communication Networks (FN) as a uniform solution to most of these networking problems. The framework of Flexible Networks can be considered as an intelligent shell enclosing existing networking architectures. An agent-oriented implementation of a flexible network is outlined. The conversion of existing networks to flexible networks is shown to be incremental, and therefore practicable.  相似文献   
37.
Phosphate coupling agents, i.e., alkyl dihydrogenphosphates containing functional groups such as olefinic, chloro, methacryloxy, and mercapto, were synthesized and allowed to react with calcium carbonate filler suspended in an aqueous medium. The modification provided the filler with good dispersibility in mineral oil. Physical properties of the vulcanized rubbers loaded with the modified fillers were found to be influenced by the functional group introduced. For example, in peroxidecured ethylene–propylene–diene rubber (EPDM), the methacryloxy group was most effective, and the mercapto group significantly enhanced the physical properties of sulfur-cured styrene–butadiene rubber (SBR), while a saturated aliphatic phosphate was ineffective in both curing systems. Deposition of the coupling agent as calcium salt onto calcium carbonate surface was observed by scanning electron micrography. The novel approach for the surface modification of calcium carbonate filler is descussed in relation to the reinforcing effects on rubbery materials.  相似文献   
38.
The effects of ferulic acid (FA) and gamma-oryzanol (OZ) supplementation on cultured red sea bream were examined. Commercial brown fish meal diets supplemented with FA (0.01-0.5%) or OZ (0.05-0.5%) were given to zero-year, cultured red sea bream for 98 days. After the experiment, the brightness of the integument color ("L" value) of FA- and OZ-administrated fish was higher than that of control fish. Furthermore, 2-Thiobarbituric acid reactive substances (TBARS) in the liver of FA- and OZ-administrated fish was lower than in control fish. These results indicate that FA and OZ suppressed not only dark-color pigmentation but also oxidative stress in cultured red sea bream.  相似文献   
39.
The effects of nonlinearity of strength envelopes on 3D slope stability analysis are investigated.A power relation for the nonlinear envelope is employed to derive the 3D factor of safety equations of an extended Spencer method hich satisfies boty force equilibrium and moment equilibrium.Then,a search procedure is presented based on dynamic programming to determine the 3D critical slip surface for a general slope,Linear and nonlinear strength envelopes used for slope stability computations are obtained by fitting curves to the 103 strength data of consolidated-undrained(CU)triaxial compression tests for compacted Israeli clay.Results of a typical 3D problem show that a linear approximation of the nonlinear strength envelope may lead to a significant overestimation of calculated safety factors.  相似文献   
40.
Hirono T  Yoshikuni Y 《Applied optics》2007,46(9):1514-1524
The fourth-order finite-difference time-domain (FDTD) method using a symplectic integrator propagator can calculate the propagation of the electromagnetic waves with very low dispersion error in the region of a constant or smoothly varying index profile. An additional technique is required for the problem with the discontinuous dielectric interfaces. We derived the third-order effective permittivities at dielectric interfaces for the fourth-order FDTD method in the case of 2D TE polarization. As the required accuracy level is increased, the memory resources used by the fourth-order FDTD method with the effective permittivities are reduced severalfold or more compared with the standard FDTD method. The accurate performance of the proposed method is demonstrated through numerical examples.  相似文献   
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