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61.
62.
Techniques are described for assessing the effectiveness with which lipids may be protected against ruminal degradation. A simple in vitro test was developed using pancreatic lipase, and this test may have application in quality control of the commercial production of protected lipid supplements, as it is applicable to supplements containing polyunsaturated or saturated lipids. All the in vitro tests overestimate the actual in vivo biological effectiveness, and this is probably due to mastication and greater microbial activity in vivo than in vitro. The poor biological response of some protected lipid supplements is most probably due to the incomplete entrapment of lipid droplets in the protein matrix.  相似文献   
63.
An analytical model of the fluid permeability of glass ribbon-reinforced organic matrix composites is presented. The analysis indicates that such composites, with ribbon aspect ratios in the range 50 to 200 offer 100 to 1000 fold improvement in permeation resistance over fibre glass composites. This is pertinent to the application of composites for storage containers, pressure vessels, and pipelines. Permeation characteristics of glass ribbon composites were determined experimentally through mass spectrographic measurements of helium penetration. These measurements qualitatively supported the analytical model.  相似文献   
64.
The authors report on the clinical data, operating technique, postoperative complications, and late results in a series of 31 epidermoid and 21 dermoid cysts of the central nervous system.  相似文献   
65.
Nineteen organosulphur solvents have been studied by gas chromatography as potential solvents for the extraction of aromatics. The activity coefficients of nine typical hydrocarbon solutes have been determined in these solvents at three temperatures. From the activity coefficient data, the selectivities of all the solvents have been calculated for benzene with respect to each of the other hydrocarbons in order to screen them for extraction studies. Solvent losses in the g.c. column were also studied.  相似文献   
66.
Periodic seasonal variations in infusion quality of orthodox Kangra tea over various growth flushes are reported. Theaflavins, thearubigins and caffeine recorded maximum content during early flush and gradual decline with progress in season, showing a minimum during main flush and slight improvement through backend flush. Flavour profile analysis also revealed qualitative and quantitative seasonal variations in aroma complex. High proportions of provisionally identified flavour components, linalool, geraniol, β-ionone, methyl salicylate, phenyl acetaldehyde, trans -2-hexenal, and several unidentified components with typical Kangra notes recorded during early flush exhibited comparatively lower contents or even total loss through main flush. Flavour quality also registered slight improvement in backend flush over main flush. Results suggest increasing crop productivity during early and backend flushes could enhance profitability.  相似文献   
67.
A study of bacterial surface oligosaccharides were investigated among different strains of Neisseria gonorrhoeae to correlate structural features essential for binding to the MAb 2C7. This epitope is widely expressed and conserved in gonococcal isolates, characteristics essential to an effective candidate vaccine antigen. Sample lipooligosaccharides (LOS), was prepared by a modification of the hot phenol-water method from which de-O-acetylated LOS and oligosaccharide (OS) components were analyzed by ES-MS-CID-MS and ES-MSnin a triple quadrupole and an ion trap mass spectrometer, respectively. Previously documented natural heterogeneity was apparent from both LOS and OS preparations which was admixed with fragments induced by hydrazine and mild acid treatment. Natural heterogeneity was limited to phosphorylation and antenni extensions to the alpha-chain. Mild acid hydrolysis to release OS also hydrolyzed the beta(1-->6) glycosidic linkage of lipid A. OS structures were determined by collisional and resonance excitation combined with MS and multistep MSn which provided sequence information from both neutral loss, and nonreducing terminal fragments. A comparison of OS structures, with earlier knowledge of MAb binding, enzyme treatment, and partial acid hydrolysis indicates a generic overlapping domain for 2C7 binding. Reoccurring structural features include a Hepalpha(1-->3)Hepbeta(1-->5)KDO trisaccharide core branched on the nonreducing terminus (Hep-2) with an alpha(1-->2) linked GlcNAc (gamma-chain), and an alpha-linked lactose (beta-chain) residue. From the central heptose (Hep-1), a beta(1-->4) linked lactose (alpha-chain), moiety is required although extensions to this residue appear unnecessary.  相似文献   
68.
The importance of open and unbuilt neighborhood spaces in residential developments has been established by numerous scholars. Having a diverse nomenclature in varied contexts, these areas are indispensable yet often neglected and designated as leftovers in contemporary planning practice. With their usefulness in the Indian context of socially active and sometimes even intrusive communities, such spaces are rapidly losing their place in present-day residential environments due to the pressure of providing for the rapidly growing population coupled with mass migratory patterns. These neighborhood spaces that impart physical, psychological, and perceptual comfort to residents have been present in spontaneously developed traditional Indian cities due to their inherent order and integrity. Moreover, some contemporary housing environments by eminent designers have also utilized the virtues of well-designed neighborhood environments. This study is a comparative analysis of three selected projects, which aspire to devise suitable methods for contemporary Indian context and achieve neighborhood comfort and an overall sense of belongingness among residents.  相似文献   
69.
This study examined the influence of a crisis on relational perceptions and the role of an empathetic response from stakeholders by investigating students’ perceptions of their relationship with a university following an on‐campus shooting. Findings show that despite the generally positive relationship, the university maintains with its students, the crisis had a negative impact on the students’ perceptions of their relationship with the university. Furthermore, results show how emotions, especially empathy, about an organization in a crisis situation can influence stakeholder relationships. This research helps provide nuance to the extant scholarship on crisis and emotions by introducing stakeholder empathy as a theoretical construct. Results also demonstrate that crisis managers who invest in relationship building before a crisis may elicit empathy more than blame in a crisis and may emerge with less relational damage.  相似文献   
70.
As the world’s population and demand for fresh water increases, new water resources are needed. One commonly overlooked aspect of the water cycle is fog, which is an important part of the hydrology of coastal, high-altitude, and forested regions. Fog water harvesting is being investigated as a sustainable alternative water resource for drinking water and reforestation. Fog water harvesting involves using mesh nets to collect water as fog passes through them. The materials of these nets, along with environmental factors such as wind speed, influence the volume of water collected. In this article, a review of current models for fog collection, designs, and applications of fog water harvesting is provided. Aspects of fog water harvesting requiring further research and development are identified. In regions with frequent fog events, fog water harvesting is a sustainable drinking water resource for rural communities with low per capita water usage. However, an analysis of fog water harvesting potential for the coastal areas of northern California (USA) showed that fog yields are too small for use as domestic water in areas with higher household water demands. Fog water shows particular promise for application in reforestation. Fog water irrigation can increase growth rates and survivability of saplings in reforestation efforts in regions with frequent fog events. Using fog collectors, denuded areas once dependent on natural fog drip can be restored, benefiting local hydrology and ecosystem recovery. Improvement in fog collector designs, materials, and models to increase collection efficiency, perhaps by inclusion of ideas from natural systems, will expand the regions where fog harvesting can be applied.  相似文献   
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