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141.
Summary Considerable improvements were made to the original Rankine method. Replacement of aspiration with an injection system contributed a great deal to the simplification of procedure, being accompanied with an increase in reproducibility. Air (flow rate 1.01/min) was used for injection because the use of inert gas gave little increase in recovery rate.Sodium bisulphite (free sulphite) and three kinds of combined sulphite compound (bisulphite adducts of acetaldehyde, pyruvic acid and D-mannose) were used to find the most suitable conditions for the separate determination of free and combine sulphites.Free sulphite was expelled from the sample by bubbling at 0 °C for 30 min. It was confirmed that no combined sulphite was dissociated under these conditions. The phosphoric acid concentration had an important role in the liberation of sulphite. When 25% phosphoric acid was used, more than 99% of free sulphite was expelled by cold bubbling and more than 99% of combined sulphite was recovered by heating afterwards for 10 min.The scope of the modified Rankine method was also extended to the determination of sulphite in concentrated orange juice.
Verwendung der modifizierten Rankine-Methode zur getrennten Bestimmung von Sulfiten in Lebensmitteln. III
Zusammenfassung Die Rankine-Methode wurde bedeutend verbessert. Ein Umtausch der Aspiration mit Blasensystem trug beträchtlich zur Vereinfachung des Bestimmungsverfahrens bei, und die Reproduzierbarkeit wurde verbessert. Luft (Fließrate 1,01/min) wurde als Blasengas benutzt, da der Gebrauch von Inertgas für die Wiederfindungsrate unbedeutend ist.Natriumhydrogensulfit (freies Sulfit) und drei Arten gebundener Sulfite (Acetaldehydhydrogensulfit, Pyruvathydrogensulfit undd-Mannosehydrogensulfit) dienten dazu, die geeignetsten Bedingungen für die getrennte Bestimmung der freien und gebundenen Sulfite zu ermitteln.Freies Sulfit wurde bei 0 °C durch 30 min Durchblasen vertrieben. Hierbei ging kein gebundenes Sulîit verloren. Die Phosphorsäurekonzentration war wichtig für die Freisetzung des Sulfites. Wenn man 25%ige Phosphorsäure verwendet, werden > 99% freien Sulfites beim Durchblasen in der Kälte vertrieben, während > 99% gebundenen Sulfites durch nachheriges 10 min langes Erhitzen wiedergewonnen werden.Die modifizierte Rankine-Methode wurde weiterhin für konzentrierte Säfte verwendet.


Studies on the Analyses of Sulphites in Foods (III)  相似文献   
142.
Managers' tasks have two aspects: to monitor (control) business activities and to plan the future based upon the monitored results. Thus a decision Support System (DSS) must have two kinds of databases appropriate for its needs.A management database, i.e., one for monitoring activities, is constructed mainly from the existing operational databases. A data cube should be employed for the logical data structure of the management database so that managers can share it and access it in multiple ways.Planning databases, i.e., those for planning activities, are constructed mostly from the management database. A table form should be employed for its logical data structure so that managers will find it easy to use.The management and planning databases should be connected through DSS's system architecture [1]. This makes the operational data (indicating business activities) directly and immediately available for management decision making.We have previously presented the DSS architecture. This paper discusses the management and planning databases from the viewpoint of it.  相似文献   
143.
Electrical and magnetic properties of the solid solutions LnV1?xMxO3 (Ln:La, Gd or Y, M:Cr or Fe) were studied in the temperature range 77–1000K. These solid solutions were all semiconductors. Their conductivity at room temperature decreased with Cr3+ or Fe3+ ion concentrations. The solid solutions LaV1?xMxO3 and YV1?xMxO3 (M:Cr or Fe) revealed an antiferromagnetism with a weak ferromagnetism and their ordering temperature increased with x. Most of the gadolinium-containing compounds were paramagnets in the measured temperature range. YV0.4Fe0.6O3 showed a thermal hysteresis at high temperatures.  相似文献   
144.
This paper proposes a quantum nondemolition measurement of the photon number in a Josephson-junction cavity. Under a current-biased Josephson junction with small capacitance, the Josephson phase fluctuates quantum-mechanically around its classical value due to the charging effect, and it couples to the photons in the junction cavity nonlinearly, which is necessary for the quantum nondemolition measurement. We show that the photon number in the junction cavity can be nondestructively measured by detecting the fluctuation of Josephson supercurrent through the junction.  相似文献   
145.
146.
Founded at the turn of the century, Japan’s steel industry ranks sixth in world production. This article, written exclusively for Journal of Metals, tells of this historical development, as well as the current problems and achievements of the Japanese steel industry.  相似文献   
147.
148.
Various functional metal-oxide coatings on glass substrate have the possibility to be used for many applications in these days. For keeping the high performance of these applications, it is very important to understand the adsorption property on those coating surfaces. However, there are few reports about such properties of metal-oxide film surface in vacuum state, especially the carbon adsorption property on fluorine-doped tin oxide (SnO2:F) film in vacuum.In this study, we have investigated the chemical state on SnO2:F film in vacuum with XPS analysis. From the results of the SnO2:F film surface analysis, the adsorbed carbon (C1s orbit) on the SnO2:F film surface and the adsorbed carbon dependence of heat treatment in vacuum were observed. Also, it was found that the adsorbed carbon distribution on the SnO2:F film existed after the heat treatment at low temperature in vacuum, uniformly spread in large area with UV light irradiation. Besides, the influence of UV light irradiation with respect to the carbon contents in the SnO2:F film was observed by SIMS analysis. As the result, it was implied that the carbon state in the SnO2:F film remained unchanged under UV light irradiation and the carbon adsorption and desorption occurred only on the surface of the SnO2:F film.  相似文献   
149.
The polymeric semiconducting carbon films are grown on silicon and quartz substrates by excimer (XeCl) pulsed laser deposition (PLD) technique using fullerene C60 precursor. The substrate temperature is varied up to 300 °C. The structure and optical properties of the films strongly depend on the substrate temperature. The grain size is increased and uniform polymeric film with improved morphology at higher temperature is observed. The Tauc gap is about 1.35 eV for the film deposited at 100°C and with temperature the gap is decreased upto 1.1 eV for the film deposited at 250 °C and increased to about 1.4 eV for the film deposited at 300 °C. The optical absorption properties are improved with substrate temperature. Raman spectra show the presence of both G peak and D peak and are peaked at about 1590 cm 1 and 1360 cm 1, respectively for the film deposited at 100 °C. The G peak position remains almost unchanged while D peak has changed only a little with temperature might be due to its better crystalline structure compared to the typical amorphous carbon films and might show interesting in device such as, optoelectronic applications.  相似文献   
150.
A safety analysis for the design of International Thermonuclear Experimental Reactor (ITER) in the Conceptual Design Activity stage was performed by the GEMSAFE methodology, and its results were compared with those of Fusion Experimental Reactor (FER), a Japan's facility planned next to JT-60. The objectives of this study are to confirm the applicability of GEMSAFE to ITER and to select design basis events of ITER and identify R&D items with comparison to FER. Function-Based Safety Analyses (FBSA) were carred out to select 19 and 25 design basis events for FER and ITER, respectively. The major reason for the difference is that ITER has a class-2 RI source, e.g., tritium of 7.5 × 105 Ci in mobile form, in the coolant for the first wall and blankets as well as a class-3 RI source, e.g., the immobile tritium of 2.2×107 Ci absorbed in first wall and dust.  相似文献   
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