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91.
In the present study we report the electrodeposition and characterization of CIS and CIGS thin films and a post-deposition thermal processing in vacuum to improve the film stoichiometry by incorporating additional In, Ga and Se. Different kinds of analyses showed that CIS as well as CIGS possess a very thin In-rich surface n-layer. The formation and characterization of solar cell structures from the electrodeposited precursor with the configuration glass/Cr/Mo/CIS(CIGS)/CdS/ZnO/MgF2 is also reported. The optoelectronic properties such as Voc, Isc, FF, η etc. of the cells are presented.  相似文献   
92.
Chemical, rheological and parotta-making characteristics of wheat-milling flour streams were studied with the main aim of developing a speciality flour for parotta. Important quality characteristics such as ash, flour colour, dry gluten content, sedimentation value, free and bound lipid content, farinograph and alveograph characteristics of the mill streams were determined. The studies showed an increase in ash, gluten content and sedimentation value with increasing numbers of breaks in the flour streams. An increase in percentage whiteness and bound lipids was observed in the first five reduction passages (C1 to C5). The alveograph characteristics indicated that the average abscissa at rupture (L) length of the curve increased with increasing reduction streams from C1 to C5, and also that the curves were better balanced when compared to 1 BK to 5 BK. The parottas made from the first five break passages had a decreased spread ratio, dull brown colour, and fused layers and lower overall quality score (43–79). The initial reduction streams (C1 to C5) produced good quality parottas in terms of appearance, spread, layers and texture. The shear force values indicating the texture of the product ranged from 1,120 to 1,250 g. The speciality flour made by combining C1 to C5 streams had 0.45% ash, 9.63% dry gluten, 45 ml sodium dodecyl sulphate sedimentation value, 0.7% free lipid and 1.8% bound lipid and produced parottas having creamish white colour, excellent pliability, thin, transparent and distinct layers, soft texture and moderate chewiness. In the mouth the parottas broke down easily, without leaving any residue. The overall quality score of parotta was highest (93.5) for the speciality flour when compared to break and reduction streams (43–77 and 56–92 respectively).  相似文献   
93.
This paper examines microalloyed steels—steels which develop their properties in the as-received condition without requiring further heat treatment, such as quenching and tempering. Microalloyed steel bars and forgings offer a clear cut potential for cost reduction and energy savings. The metallurgy for producing high strength microalloyed bars and forgings is in place. However, significant improvement in the notch toughness of these materials is necessary, and the metallurgy required to achieve this toughness improvement exists. With application of the necessary metallurgical techniques in rolling mills and forge shops, the utilization of high strength microalloyed steel bars and forgings will increase greatly.  相似文献   
94.
The rheological properties and physical stability of mangosteen (Garcinia mangostana L.) extract in oil-in-water (MIO/W) emulsions were investigated. Rheological study on the emulsions exhibited Newtonian flow behavior. The 20?wt.% emulsion showed higher apparent viscosity than 10?wt.% MIO/W sample. The effects of salt (NaCl) concentration (0, 50, 100, and 200?mM) and heat treatment (70?°C) on the stability of the emulsions were also examined. Heat (70?°C)- and NaCl (100 and 200?mM)-treated emulsions showed creaming and droplet aggregation on storage for a period of 60?days. The 10?wt.% MIO/W emulsions stored at 4?°C showed a homogeneous distribution of oil droplets with good stability to creaming and viscosity independent of shear stress (i.e., a Newtonian liquid).  相似文献   
95.
Effect of replacement of wheat flour with a combination of soy protein isolate, oat bran and chickpea flour (SPOBCP) at the levels of 20%, 40% and 60% and addition of combination of additives such as fungal ??-amylase, dry gluten powder, sodium stearoyl-2-lactylate, hydroxypropylmethylcellulose (CA) on the rheological and nutritional characteristics of bread was studied. Use of SPOBCP decreased farinograph dough stability, increased pasting temperature, decreased cold paste viscosity and overall quality score of bread. Scanning electron microscopy images showed higher degree of disruption of protein matrix in bread dough with 60% SPOBCP than 20% and 40% SPOBCP. Addition of 60% SPOBCP resulted in flat, uneven shaped bread with an overall quality score of 38 when compared with 54, 81 and 91 for breads with 40%, 20% and 0% SPOBCP, respectively. However, use of CA increased the strength of the dough and improved the overall quality of bread with 40% SPOBCP. Nutritional profile of bread with 40% SPOBCP?+?CA showed higher protein, in vitro protein digestibility, total dietary fibre, resistant starch, ??-glucan and lower starch hydrolysis index than control bread.  相似文献   
96.
Studies were carried out on the replacement of sugar with stevioside and liquid sorbitol (SO); addition of hydrocolloids, emulsifiers with and without 10% debittered fenugreek seed powder (DFSP) to a mixture of stevioside and SO on the rheological, microstructural and quality characteristics of cake. Experimental data showed that addition of sugar increased the amylograph viscosity of wheat flour paste during heating and cooling while SO at different percentages decreased these viscosities, however addition of combination of hydrocolloid (xanthan, XA) and emulsifier (polysorbate-60, PS-60) increased the viscosity of wheat flour paste with 100% SO. Addition of combination of XA + PS-60 improved distribution pattern of air cells, increased batter viscosity, cohesiveness, overall quality score of cake with 100% SO and allowed incorporation of DFSP to improve the functional characteristics of cake. Evaluation of composition of developed cake showed negligible sucrose content, perceptible fenugreek flavor and increased dietary fiber as against cake with sugar.  相似文献   
97.
Austenite stainless steels (316L, 317L, and 349™) have been coated with 0.6 μm thick SnO2:F by low-pressure chemical vapor deposition and investigated in simulated polymer electrolyte membrane fuel cell (PEMFC) environments. The results showed that substrate steel has a significant influence on the behavior of the coating. Coated 316L showed a steadily increasing anodic current in PEMFC environments, indicating that it is not suitable for this alloy/coating combination. Coated 349™ showed a cathodic current in the PEMFC anode environment, demonstrating its stability in the PEMFC cathode environment. Coated 317L exhibited a stable anodic current after a current peak (at ca. 14 min) in the PEMFC anode environment, and showed an extremely stable low current in PEMFC cathode environment, suggesting the possibility of using SnO2:F coated 317L for PEMFC bipolar plate applications.  相似文献   
98.
Price volatility analysis has been reported in the literature for most competitive electricity markets around the world. However, no studies have been published yet that quantify price volatility in the Ontario electricity market, which is the focus of the present paper. In this paper, a comparative volatility analysis is conducted for the Ontario market and its neighboring electricity markets. Volatility indices are developed based on historical volatility and price velocity concepts, previously applied to other electricity market prices, and employed in the present work. The analysis is carried out in two scenarios: in the first scenario, the volatility indices are determined for the entire price time series. In the second scenario, the price time series are broken up into 24 time series for each of the 24 h and volatility indices are calculated for each specific hour separately. The volatility indices are also applied to the locational marginal prices of several pricing points in the New England, New York, and PJM electricity markets. The outcomes reveal that price volatility is significantly higher in Ontario than the three studied neighboring electricity markets. Furthermore, comparison of the results of this study with similar findings previously published for 15 other electricity markets demonstrates that the Ontario electricity market is one of the most volatile electricity markets world-wide. This high volatility is argued to be associated with the fact that Ontario is a single-settlement, real-time market.  相似文献   
99.
The paper presents the experimental results showing that the crystalline phase of the nano-particles, synthesized in a DC transferred arc thermal plasma reactor, critically depend on the operating pressure in the reaction zone. The paper reports about the changes in crystalline phases of three different compounds namely: aluminium oxide (Al2O3), aluminium nitride (AlN) and iron oxide (FexOy) synthesized at 760 Torr and 500 Torr of operating pressures. The major outcome of the present work is that the phases having higher defect densities are more probable to form at the sub-atmospheric operating pressures. The variations in the crystalline structures are discussed on the basis of the change in the temperature during the nucleation process, prevailing at the boundary of the plasma, on account of the ambient pressures. The as-synthesized nano-particles were examined by X-ray diffraction analysis and transmission electron microscopy. In addition, the confirmatory analysis of the crystalline phases of iron oxides was carried out with the help of Mössbauer spectroscopy.  相似文献   
100.
This correspondence proposes two novel control schemes with variable state-feedback gain to stabilize a Takagi-Sugeno (T-S) fuzzy system. The T-S fuzzy model is expressed as a linear plant with nonlinear disturbance terms in both schemes. In controller I, the T-S fuzzy model is expressed as a linear plant around a nominal plant arbitrarily selected from the set of linear subsystems that the T-S fuzzy model consists of. The variable gain then becomes a function of a gain parameter that is computed to neutralize the effect of disturbance term, which is, in essence, the deviation of the actual system dynamics from the nominal plant as the system traverses a specific trajectory. This controller is shown to stabilize the T-S fuzzy model. In controller II, individual linear subsystems are locally stabilized. Fuzzy blending of individual control actions is shown to make the T-S fuzzy system Lyapunov stable. Although applicability of both control schemes depends on the norm bound of unmatched state disturbance, this constraint is relaxed further in controller II. The efficacy of controllers I and II has been tested on two nonlinear systems  相似文献   
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