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1.
The efficiency of areas of science was evaluated using the DEA method. Areas achieving a maximum orientation or regard of international publication are rated as efficient. The areas of reproductive medicine, organic and inorganic chemistry in the former Federal Republic can thus be regarded as efficient areas of science. No area of scientific research in the former East Germany was able to achieve the optimum. The determinant in this connection is the adverse situation with respect to international orientation whilst no substantial difference in regard for further research could be detected between East and West German research.  相似文献   
2.
This study aims to describe the procedures and practices used in local production of raw milk butter. The demand for local products is increasing; hence, there is a need to describe the practices used in the artisanal production of raw milk butter. Therefore, a survey of 147 raw milk butter producers was carried out. The results from the survey indicate that there is not one single way to produce butter at artisanal level. In terms of maturation, six temperature sequences were distinguished. Attention is required at every step of production starting from breeding.  相似文献   
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A Mixed-Mode BIST Scheme Based on Folding Compression   总被引:1,自引:0,他引:1       下载免费PDF全文
In this paper a new scheme of mixed mode scan-based BIST is presented with complete fault coverage,and some new concepts of folding set and computing are introduced.This scheme applies single feedback polynomial of LFSR for generation pseudo-random patterns as well as for compressing and extending seeds of folding sets and an LFSR, where we encode seed of folding set as an initial seed of LFSR .Moreover these new techniques are 100% compatible with scan design .Experimental results show that the proposed scheme outperforms previously published approaches based on the reseeding of LFRSRs.  相似文献   
5.
Plants emit a wide range of volatile organic compounds in response to damage by herbivores, and many of the compounds have been shown to attract the natural enemies of insect herbivores or serve for inter- and intra-plant communication. Most studies have focused on volatile emission in the laboratory while little is known about emission patterns in the field. We studied the emission of volatiles by Trifolium pratense (red clover) under both laboratory and field conditions. The emission of 24 compounds was quantified in the laboratory, of which eight showed increased emission rates after herbivory by Spodoptera littoralis caterpillars, including (E)-β-ocimene, the most abundant compound, (Z)-β-ocimene, linalool, (E)-β-caryophyllene, (E,E)-α-farnesene, 4,8-dimethyl-1,3,7-nonatriene (DMNT), 1-octen-3-ol, and methyl salicylate (MeSA). While most of these compounds have been reported as herbivore-induced volatiles from a wide range of plant taxa, 1-octen-3-ol seems to be a characteristic volatile of legumes. In the field, T. pratense plants with varying herbivore damage growing in established grassland communities emitted only 13 detectable compounds, and the correlation between herbivore damage and volatile release was more variable than in the laboratory. For example, the emission of (E)-β-ocimene, (Z)-β-ocimene, and DMNT actually declined with damage, while decanal exhibited increased emission with increasing herbivory. Elevated light and temperature increased the emission of many compounds, but the differences in light and temperature conditions between the laboratory and the field could not account for the differences in emission profiles. Our results indicate that the release of volatiles from T. pratense plants in the field is likely to be influenced by additional biotic and abiotic factors not measured in this study. The elucidation of these factors may be important in understanding the physiological and ecological functions of volatiles in plants.  相似文献   
6.
This paper presents the analysis and validation of a real-time AC drive simulator. Real-time simulation has been used for over a decade in power systems engineering to test controllers thoroughly, efficiently, and safely. The development and testing of large DC drives could benefit from this type of simulation, but real-time power system simulators have modeling restrictions preventing stable and accurate simulation of isolated drives switching at high frequencies. These restrictions can be overcome by combining in a single model both the power converter and motor models. After discussing the salient issues related to the real-time simulation of DC drives, a prototype real-time simulator for drives is described. Its ability to accurately emulate the behavior of large drives is demonstrated through two case studies. A first case study demonstrates the feasibility of simulating a drive of typical complexity in real-time. The second case study demonstrates how the controller for a PWM VSI fed induction motor, switching at 4 kHz, is designed, implemented in a microcontroller and tested in real-time using a simulated inverter, motor and load. Comparisons against results obtained with another simulation tool, which uses extremely accurate variable-step integration algorithms, demonstrates the validity of our approach.  相似文献   
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Within the scope of the characterization of a commercial pectate lyase (PAL) the pattern of substrate degradation by that enzyme was investigated with oligogalacturonic acids as well as pectins with various degrees of esterification as substrates. For this purpose an analytical size exclusion chromatographie method (HPSEC) was elaborated in order to evaluate the reaction products of the degraded substrates over the whole range of molecular weight with the main interest lying in the emerging oligogalacturonic acids. The degradation of polygalacturonic acid by PAL was additionally investigated by means of thin-layer chromatography (TLC) and viscosimetry. Furthermore spontaneous depolymerization and deesterification of the substrates occurring under the chosen conditions were examined. The PAL showed to be anendo-enzyme both by means of TLC and HPSEC. Polygalacturonic acid was broken down, mainly generating unsaturated tri- and digalacturonic acid; the corresponding monomer was not found. The mode of cleavage is discussed.  相似文献   
9.
Blei in Pilzen     
Zusammenfassung Der Bleigehalt von 222 Arten (494 Proben) wildgewachsener Speise- und Giftpilze aus süddeutschen Gegenden ohne crhöhte Bleibelastung wurde durch flammenlose Atomabsorptionsspektroskopie in einer Graphitrohrküvette bestimmt. Er lag zwischen <2,0 und 40,5 mg/kg Trokkensubstanz, entsprechend <0,1 und 3,0 mg/kg Frischpilz, im Mittel bei 10,6 mg/kg Trockensubstanz = 1,06 mg/kg Frischpilz.
Lead in mushrooms
Summary The lead content of 222 species of wild mushrooms, either edible or poisonous, was determined by graphite furnace atomic absorption spectroscopy. Altogether 494 samples, grown in rural regions of southern Germany, were tested. The lead content was between < 2.0 and 40.4, on the average 10.6 mg/kg dry weight, equivalent to < 0.1 and 3.0, on the average 1.06 mg/kg fresh weight.


Mit Unterstützung der Deutschen Forschungsgemeinschaft  相似文献   
10.
First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high‐efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti‐reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two‐step fine‐line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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