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91.
Four strains of lactic acid bacteria were used as pure or mixed cultures to investigate the texture-promoting capacity and exopolysaccharides (EPS) formation in three different oat-based, non-dairy milk products, Adavena G40, Adavena M40 (both with a dry matter content of 20%) and Mill Milk (with a dry matter content of 10%). Viscosity was measured at two different shear rates during 2 min of shear thinning. The highest viscosity was measured at a shear rate of 129 s-1 when a mixed culture consisting of Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772 and Lactobacillus brevis DSM 1269 was grown at 30 °C in the medium containing mostly glucose as the carbohydrate source (Adavena G40). The mixed culture consisting of Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772 and Streptococcus thermophilus DSM 20259 gave the highest viscosity when using the medium with a dry matter content of 20% and maltose as the main carbohydrate source (Adavena M40). The EPS formation in the Adavena G40 medium was confirmed by isolating the soluble polymer fraction after fermentation. A higher yield of polymer dry mass was obtained from the samples with higher viscosity. The study shows that the co-operative growth that occurs when using mixed cultures also influences the EPS formation and final viscosity in the different oat-based media. This knowledge is of importance when strains are selected for the development of new kinds of fermented, oat-based, non-dairy products. 相似文献
92.
93.
Mahrer Alvin R.; Dessaulles André; Nadler Wayne P.; Gervaize Patricia A.; Sterner Irit 《Canadian Metallurgical Quarterly》1987,24(1):7
10 clinical psychologists applied a twelvefold category system of good and very good moments of client movement, progress, improvement, process, or change to 2 consecutive middle sessions of experiential psychotherapy. Findings show (1) a large proportion of good and very good moments in both sessions, (2) the distribution of these moments into a distinctive subset of the 12 categories, and (3) the occurrence of series and phases of good moments rather than discrete events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
A compact heterojunction bipolar transistor (HBT) model was employed to simulate the high frequency and high power performances of SiC-based bipolar transistors. Potential 6H-SiC/3C-SiC heterojunction bipolar transistors (6H/3C-HBT's) at case temperatures of 27°C (300 K) through 600°C (873 K) were investigated. The high frequency and high power performance was compared to AlGaAs/GaAs HBT's. As expected, the ohmic contact resistance limits the high frequency performance of the SiC HBT. At the present time, it is only possible to reliably produce 1×10-4 Ω-cm2 contact resistances on SiC, so an fT of 4.4 GHz and an fmax of 3.2 GHz are the highest realistic values. However, assuming an incredibly low 1×10-6 Ω-cm2 contact resistance for the emitter, base, and collector terminals, an fT of 31.1 GHz and an fmax of 12.7 GHz can be obtained for a 6H/3C-SiC HBT 相似文献
95.
Lifetime distribution functions and current network age data can be combined to provide an assessment of the future replacement needs for drinking water distribution networks. Reliable lifetime predictions are limited by a lack of understanding of deterioration processes for different pipe materials under varied conditions. An alternative approach is the use of real historical data for replacement over an extended time series. In this paper, future replacement needs are predicted through historical data representing more than one hundred years of drinking water pipe replacement in Gothenburg, Sweden. The verified data fits well with commonly used lifetime distribution curves. Predictions for the future are discussed in the context of path dependence theory. 相似文献
96.
97.
M. Mosihuzzaman M. Fazlul Hoque Tofail A. Chowdhury Olof Theander Lennart N. Lundgren 《Journal of the science of food and agriculture》1988,42(2):141-147
Fresh and retted bark and stem of the Corchorus capsularis and Corchorus olitorius species of jute plant were analysed for their phenolic acid contents. Free and bound phenolic acids were identified and quantitatively determined by means of HPLC. Ferulic and p-coumaric acids were the main components, whereas p-hydroxybenzoic, protocatechuic, vanillic and caffeic acids were present in varying amounts in different jute fractions. The stem contained more free phenolic acids than the bark, and the differences were very pronounced in the retted samples. On the other hand, the bark from all four samples contained more extractable ester-bound phenolic acid than the stem. The stem of fresh C. olitorius and retted bark (fibre) of both species contained more non-extractable bound phenolic acids, in particular p-coumaric acid, than the other fractions. 相似文献
98.
99.
Olof J. Staffans 《Systems & Control Letters》1996,29(3):69
The standard state space solution of the finite-dimensional continuous time quadratic cost minimization problem has a straightforward extension to infinite-dimensional problems with bounded or moderately unbounded control and observation operators. However, if these operators are allowed to be sufficiently unbounded, then a strange change takes place in one of the coefficients of the algebraic Riccati equation, and the continuous time Riccati equation begins to resemble the discrete time Riccati equation. To explain why this phenomenon must occur we discuss a particular hyperbolic PDE in one space dimension with boundary control and observation (a transmission line) that can be formulated both as a discrete time system and as a continuous time system, and show that in this example the continuous time Riccati equation can be recovered from the discrete time Riccati equation. A particular feature of this example is that the Riccati operator does not map the domain of the generator into the domain of the adjoint generator, as it does in the standard case. 相似文献
100.
The equilibrium distribution ratio of phosphorus between BaO-BaF2-MnO slags and Mn(62–73%)-Fe-Csat-P melts has been determined for different slag compositions, oxygen partial pressures and at 1573–1673 K. The results showed that with a certain content of BaO in the slags, the phosphorus distribution ratio increased with increasing oxygen partial pressure up to about 10?17 atm. A high oxygen partial pressure resulted in a substantial oxidation of manganese from metal to slag. The phosphate capacity of BaO-BaF2-MnO slags increased with the BaO content and decreased with the MnO content in the investigated slag composition range. A high temperature resulted in a low phosphorus distribution ratio. For a BaO(50%)-BaF2(47%)-MnO(3%) slag, the effect of temperature on the phosphate capacity in the range of 1573–1673 K could be expressed as: (1) The heat of reaction: (2) was estimated to be ?1107 kJ/mole. 相似文献