全文获取类型
收费全文 | 996篇 |
免费 | 56篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 8篇 |
综合类 | 8篇 |
化学工业 | 235篇 |
金属工艺 | 16篇 |
机械仪表 | 11篇 |
建筑科学 | 47篇 |
能源动力 | 29篇 |
轻工业 | 146篇 |
水利工程 | 12篇 |
石油天然气 | 2篇 |
无线电 | 131篇 |
一般工业技术 | 173篇 |
冶金工业 | 84篇 |
原子能技术 | 13篇 |
自动化技术 | 138篇 |
出版年
2023年 | 11篇 |
2022年 | 12篇 |
2021年 | 23篇 |
2020年 | 12篇 |
2019年 | 16篇 |
2018年 | 21篇 |
2017年 | 27篇 |
2016年 | 20篇 |
2015年 | 25篇 |
2014年 | 39篇 |
2013年 | 35篇 |
2012年 | 55篇 |
2011年 | 57篇 |
2010年 | 46篇 |
2009年 | 47篇 |
2008年 | 30篇 |
2007年 | 45篇 |
2006年 | 33篇 |
2005年 | 32篇 |
2004年 | 27篇 |
2003年 | 29篇 |
2002年 | 21篇 |
2001年 | 14篇 |
2000年 | 16篇 |
1999年 | 16篇 |
1998年 | 33篇 |
1997年 | 26篇 |
1996年 | 24篇 |
1995年 | 19篇 |
1994年 | 12篇 |
1993年 | 16篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 8篇 |
1989年 | 10篇 |
1988年 | 5篇 |
1987年 | 10篇 |
1986年 | 12篇 |
1985年 | 18篇 |
1984年 | 16篇 |
1983年 | 10篇 |
1982年 | 11篇 |
1981年 | 18篇 |
1980年 | 14篇 |
1978年 | 9篇 |
1977年 | 14篇 |
1976年 | 13篇 |
1975年 | 6篇 |
1974年 | 3篇 |
1973年 | 4篇 |
排序方式: 共有1053条查询结果,搜索用时 15 毫秒
1.
2.
Werner Strohmaier Henning Klostermeyer Paul Deuritz Erich Windhab 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(6):531-535
Summary Current texture-measuring instruments and a recently developed measuring method (two-dimensional measuring of the force necessary to spread a sample) were compared in measuring the spreadability of processed cheese. How far subjective assessment by a qualified panel correlates with the instrumental results in determining spreadability and firmness was also investigated. Samples of processed cheese with various consistencies were measured by an Universal testing machine, a buttermeasuring instrument (DIN 10331), a rotational-type rheometer (oscillation mode) and a two-dimensional force measuring instrument. The evaluation of the results shows that an oscillating rheometer is most suitable to measure the spreadability of processed cheese; the correlation coefficient (r) between the dynamic Weissenberg number, calculated from parameters of the rheometer, and the subjective judgement by the panel wasr=0.91. For the determination of firmness the two-dimensional force measuring instrument is most suitable. The correlation coefficient between the parameter tangential energy (S
t) and the sensorially evaluated firmness wasr=0.95.
Vergleich verschiedener Bestimmungsmethoden für die Streichfähigkeit und Festigkeit von Schmelzkäse
Zusammenfassung Verschiedene gebräuchliche Meßinstrumente und ein neu entwickeltes Gerät zur zweidimensionalen Messung der Kräfte, die zum Ausstreichen einer Probe erforderlich sind, wurden vergleichend zur Charakterisierung der Streichfähigkeit von Schmelzkäse erprobt. Dabei wurde auch geprüft, inwieweit die subjektiven Beurteilungen eines qualifizierten Prüferpanels mit den Meßwerten für Streichfähigkeit und Festigkeit korrelierten. Gemessen wurde mit einer Universalprüfmaschine, dem Butterprüfgerät (DIN 10331), einem Rotationsrheometer und mit dem zweidimensional registrierenden Kraftmeßgerät. Dabei zeigte sich, daß das Rheometer im oscillierenden Modus die Streichfähigkeit am besten zu charakterisieren vermag. Die Korrelation zwischen den Rheometerwerten, berechnet als dynamische Weissenbergzahl, und den sensorisch ermittelten Werten für die Streichfähigkeit betrugr=0,91. Zur Bestimmung der Festigkeit ist das zweidimensional registrierende Kraftmeßgerät am besten geeignet, was sich in einem Korrelationskoeffizienten vonr=0,95 zwischen dem ParameterS t und den im Sensoriktest ermittelten Werten für dieFestigkeit ausdrückt.相似文献
3.
TIBER II is designed to be a minimum size and cost candidate for an international Engineering Test Reactor. High-current density Nb3Sn superconducting magnets with radiation-tolerant polymide insulation is combined with a minimum thickness tungsten inbored shield and a common, external vacuum boundary to minimize the inner radial build of the tokamak core. This results in a major radius of 3 m, compared to 5 m for previous ETR designs such as INTOR, with correspondingly lower costs expected. Cyclic stress fatigue limits the number of pulses so that steady-state current drive, based on a combination of neutral beams, lower hybrid and ECH, is designed to achieve reactor-relevant nuclear testing conditions (Fluence 3MW yr/m2, rwall > 1 MW/m2 in steady state).This report is abstracted from a more complete information document UCID-20863 with numerous authors. See Ref. l for complete credits. 相似文献
4.
Activated carbon is a suitable adsorbent for removal of hydrogen sulphide from natural, synthesis or other product gases. The process depends predominantly on physical adsorption, though catalytic oxidation is also involved. During catalytic oxidation the H2S is converted in the presence of oxygen to elemental sulphur, which is adsorbed onto the internal surface of the activated carbon, thus leading to a sulphur load of up to 120% by weight. The oxidation rate depends on the partial pressure of both reactants, H2S and O2 and is largely controlled by the characteristics of the activated carbon. The activity of the catalyst can be improved by impregnating the activated carbon with promoters such as iron and iodine. The regeneration of spent carbon is currently carried out using hot gas desorption methods at temperatures around 450 °C. 相似文献
5.
Justifying security expenditures in difficult economic times is problematic at best, career ending at worst. This article provides a methodology to improve the probability of budget success based on risk assessment techniques, proven project management skills, and economics. 相似文献
6.
L.J. Zeballos O.D. Quiroga G.P. Henning 《Engineering Applications of Artificial Intelligence》2010,23(2):229-248
This contribution presents an integrated constraint programming (CP) model to tackle the problems of tool allocation, machine loading, part routing, and scheduling in a flexible manufacturing system (FMS). The formulation, which is able to take into account a variety of constraints found in industrial environments, as well as several objective functions, has been successfully applied to the solution of various case studies of different sizes. Though some of the problem instances have bigger sizes than the examples reported to date in literature, very good-quality solutions were reached in quite reasonable CPU times. This good computational performance is due to two essential characteristics of the proposed model. The most significant one is the use of two sets of two-index variables to capture manufacturing activities instead of having just one set of four indexes. Thus, dimensionality is greatly reduced. The other relevant feature is the fact that the model relies on an indirect representation of tool needs by means of tool types, thus avoiding the consideration of tool copies. 相似文献
7.
Arnaud Grasset Philippe Millet Philippe Bonnot Sami Yehia Wolfram Putzke-Roeming Fabio Campi Alberto Rosti Michael Huebner Nikolaos S. Voros Davide Rossi Henning Sahlbach Rolf Ernst 《International journal of parallel programming》2011,39(3):328-356
Reconfigurable computing offers a wide range of low cost and efficient solutions for embedded systems. The proper choice of the reconfigurable device, the granularity of its processing elements and its memory architecture highly depend on the type of application and their data flow. Existing solutions either offer fine grain FPGAs, which rely on a hardware synthesis flow and offer the maximum degree of flexibility, or coarser grain solutions, which are usually more suitable for a particular type of data flow and applications. In this paper, we present the MORPHEUS architecture, a versatile reconfigurable heterogeneous System-on-Chip targeting streaming applications. The presented architecture exploits different reconfigurable technologies at several computation granularities that efficiently address the different applications needs. In order to efficiently exploit the presented architecture, we implemented a complete software solution to map C applications to the reconfigurable architecture. In this paper, we describe the complete toolset and provide concrete use cases of the architecture. 相似文献
8.
9.
Fujio Takahashi Ernst -H. Reimerdes Henning Klostermeyer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,164(3):163-166
Summary In casein-containing agarose gels, pepsin and chymosin form radial diffusion zones; the diameters of these zones show rectilinear correlations with the logarithm of the enzyme concentration at constant time. The sensitivity for both enzymes is below 1 g. Addition of the inhibitor pepstatin A to these enzymes causes a reduction of the diameters of the diffusion zones, with large differences for both the enzymes. With this procedure, the pepsin/chymosin ratio in rennet preparations was assayed with an accuracy of ±5%. Identification of the inhibitors allows the determination of amounts in the namomole range. This method is a simple technique for the evaluation of proteinases and their inhibitors in screening systems.
Geldiffusion — eine einfache und empfindliche Technik für den Nachweis von Proteinaseinhibitoren und die Anwendung für die Bestimmung von Proteinasen in Gemischen
Zusammenfassung In caseinhaltigen Agarosegelen erzeugen sowohl Pepsin wie Chymosin radiale Diffusionszonen, deren Durchmesser bei gegebener Zeit dem Logarithmus der Enzymmenge proportional ist. Die Bestimmungsgrenze liegt für beide Enzyme unter 1 g. Bei Zugabe des Inhibitors Pepstatin A zu den Proteinasepräparaten werden die Diffusionszonen beider Proteinasen verkleinert, aber in unterschiedlichem Ausmaße. Auf dieser Basis kann in technischen Labpräparaten das Mengenverhältnis Pepsin/Chymosin mit einer Genauigkeit von ±5% bestimmt werden. Bei Umkehr der Reaktion zum Nachweis des Inhibitors sind Mengen im Bereich von 10–9 Mol sicher erfaßbar. Die Methodik ist verallgemeinerungsfähig als Screening-Test für Proteinaseinhibitoren.相似文献
10.
Bernd-Michael Neumann Hans-Georg Henning Dieter Gloyna Margit Bandlow 《Advanced Synthesis \u0026amp; Catalysis》1976,318(5):823-834
Sydnone Ethylenes. I Stereoselective Synthesis of Sydnone Ethylenes from Sydnone Aldehydes Sydnones are formylated in 4-position by the VILSMEIER -HAAK reaction. N(3)-Methyl- and N(3)-(p-Anisyl)-sydnone-(4)-carboxaldehyde react stereoselectively to sydnone ethylenes with diethyl ethoxycarbonylmethanephosphonate by HORNER reaction and with arylmethylphosphonium salts by WITTIG reaction in the presence of strong bases. In the latter case, especially in the absence of lithium cations, Z-selectivity is observed which is explained by electronic interaction between the sydnone cyclus and the aromatic substituent of the phosphine ylid in the first step of the reaction. The configuration of the obtained Z- and E-sydnone ethylenes is determined by means of 1H-NMR- and IR-spectra. 相似文献