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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.
Christian Wolf Martin Prechtl René Bauer Michael Dinkel Fabian Beck Leopold Franz Viktor Neumeyer 《真空研究与实践》2023,35(1):35-39
To mark our anniversary, we are presenting articles that have been particularly appreciated by readers of our online edition once again in print. Here: 3D-Printing for High Vacuum Applications 3D printing technology has made the leap from a home-based private practice to industrial manufacturing. Due to the increasing reliability of printers and increasing material diversity, especially in the metal sector, double-digit percentage growth rates are possible in the coming years. This thesis deals with the manufacture of parts made by 3D printing for high vacuum application. Different components are printed and examined for their vacuum compatibility. As shown furthermore, conventionally made standard components can be vacuum sealed to printed parts, which enables cost-effective production of more complex components, such as e.g. a vacuum chamber allows. In addition, functional components can already be realized in the manufacturing process. The integration of a system of flow channels directly into the wall of a chamber is just one example. Thus, such a chamber can be heated during evacuation and effectively cool in later operation. 相似文献
3.
4.
梁华国 《计算机科学技术学报》2002,17(2):0-0
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.
Rose N. Kigathi Sybille B. Unsicker Michael Reichelt Jürgen Kesselmeier Jonathan Gershenzon Wolfgang W. Weisser 《Journal of chemical ecology》2009,35(11):1335-1348
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.
Champagne R. Dessaint L.-A. Fortin-Blanchette H. Sybille G. 《Power Electronics, IEEE Transactions on》2004,19(2):336-345
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
7.
8.
Sybille Neidhart Achim Gessler Christa Hannak Hans -Ulrich Endreß Karlheinz Gierschner 《European Food Research and Technology》1994,198(4):317-324
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.
Ruth Seeger Else Meyer und Sybille Schönhut 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1976,162(1):7-10
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.
Mit Unterstützung der Deutschen Forschungsgemeinschaft 相似文献
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.
Kristine Drew Sybille Hopman Matthias Hrteis Stefan W. Glunz Filip Granek 《Progress in Photovoltaics: Research and Applications》2011,19(3):253-259
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