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171.
This article looks at the applications and benefits of ceramic membranes. It covers crossflow technologies, membrane elements and modules and recent developments in this segment of membrane technology. Also presented are examples that demonstrate the ability of ceramic membranes to concentrate process streams, recover valuable products, and increase yields — making them a cost-effective and often preferred method of filtration. 相似文献
172.
173.
G. S. Sailaja S. Velayudhan M. C. Sunny K. Sreenivasan H. K. Varma P. Ramesh 《Journal of Materials Science》2003,38(17):3653-3662
Chitosan (CHI) has been complexed with polyacrylic acid (PAA) in the presence of hydroxyapatite (HAP) to prepare composites intended for bone substitute applications. Thermogravimetric analysis of the composite showed that the presence of HAP had little effect on the degradation profile of the polyelectrolyte complex (PEC), except for the onset of degradation. Optimum compressive strength was observed for 70-weight percentage HAP filled PEC. The morphological analysis revealed that the HAP particles were uniformly distributed in the PEC matrix. The results indicate that HAP filled PEC of CHI and PAA could be prepared following the proposed simple route. 相似文献
174.
Padmaja R. Jonnalagadda Pratima Rao Ramesh V. Bhat & A. Nadamuni Naidu 《International Journal of Food Science & Technology》2004,39(2):125-131
The type and extent of colours added to ready‐to‐eat (RTE) foods prepared in the non‐industrial sector of India was investigated. Of the 545 RTE foods analysed, 90% contained permitted colours, 2% contained a combination of permitted and non‐permitted colours and 8% contained only non‐permitted colours. However in RTE foods with permitted colours, 73% exceeded 100 ppm, as prescribed by the Prevention of Food Adulteration Act of India, and 27% were within the prescribed levels. Among the permitted colours, tartrazine was the most widely used colour followed by sunset yellow. The maximum concentration of colours was detected in sweet meats (18 767 ppm), non‐alcoholic beverages (9450 ppm), miscellaneous foods (6106 ppm) and hard‐boiled sugar confectioneries (3811 ppm). Among the non‐permitted colours found, rhodamine was most commonly used. Some of the foods, such as savouries and miscellaneous foods like sugar coated aniseed and almond milk, are not supposed to contain colours as per the Prevention of Food Adulteration Act, but were found to contain colours. 相似文献
175.
SOL (Secure Operations Language) is a synchronous programming language for implementing reactive systems. The utility of SOL hinges upon the fact that it is a secure language, i.e., most programs in SOL are amenable to fully automated static analysis techniques, such as automatic theorem proving using decision procedures or model checking. Among the unique features of SOL is the ability to express a wide class of enforceable safety and security policies (including the temporal aspects of software component interfaces) in the language itself, thereby opening up the possibility of eliminating runaway computations and malicious code, such as worms and viruses. 相似文献
176.
Smita H. Panda Samir K. Naskar Paramasivan Sethuraman Sivakumar & Ramesh C. Ray 《International Journal of Food Science & Technology》2009,44(2):288-296
Sweet potato (SP) is an important root crop grown all over the world and consumed as a vegetable, boiled, baked or often fermented into food and beverages. The grated SP roots [non- boiled and fully boiled (boiled in water at 100 °C for 15 min) were treated with 0.05% of commercial pectinase enzyme (Pectinex, Novoenzyme) in order to extract the juice. The fresh juice was inoculated with Lactobacillus plantarum MTCC 1407 culture at 28 ± 2 °C for 48 h to produce lacto-juice (LJ). The anova analysis of analytical data revealed that there was significant effect of boiling conditions (fully boiled and non-boiled) on pH [ F (1, 4) = 220.5, P < 0.001), TA [ F (1, 4) = 78.89, P < 0.01], starch [ F (1, 4) = 26.63, P < 0.01), total sugar [ F (1, 4) = 61.36, P < 0.01) and anthocyanin [ F (1, 4) = 32.86, P < 0.01) but not on reducing sugar [ F (1, 4) = 2.48, P = 0.19). Sensory evaluation rated the SP LJ acceptable based on texture, taste, aroma, flavour and after taste. LJ prepared from fully boiled roots with 10% cane sugar was most preferred by a consumer's panelist based on Linear Discriminant Analysis. Principal component analyses (PCA) reduced the seven original analytical variables to three independent components (factors), which accounted for 99.9% of the total variations. Similarly, six original sensory variables were reduced to two independent components, which accounted for 65.7% of the total variations. 相似文献
177.
Discharge Relation for Cutthroat Flume under Free-Flow Condition 总被引:2,自引:0,他引:2
Vivek L. Manekar Prakash D. Porey Ramesh N. Ingle 《Canadian Metallurgical Quarterly》2007,133(5):495-499
A cutthroat flume is commonly used as flow measuring device for open-channel flow due to ease of fabrication and installation. In most of the cases it is difficult to calibrate the flume in the field. Therefore, accurate relation between discharge and upstream head applicable for all sizes of cutthroat flume is needed. Seven different sizes of cutthroat flumes, having different length to throat width ratios, are fabricated and tested in the laboratory under free-flow condition. Selecting groups of different variables describing flow through a cutthroat flume number of dimensionless parameters are formed. Regression analysis of experimental data is carried out between all possible combinations of pairs of dimensionless parameters and the pair giving the best correlation is selected. Using the selected pair, relation between dimensionless parameters of discharge and head is developed. The relation is simple and convenient to use and, at the same time, more accurate compared to methods available in literature for prediction of discharge. 相似文献
178.
Wojciech Fabianowski Ralph Jaccodine Ramesh Kodnani Raymond Pearson Piotr Smektala 《Advanced functional materials》1995,5(4):199-213
Two polymeric coatings, a silicone gel (Dow Corning 6646) and an epoxy resin (Dexter FP 4402), were glob-top coated onto representative microelectronic circuits, AT&T Triple Track Testers (TTTs), and subjected to the Pressure Cooker Test (PCT). Coupling monolayers were self- assembled on the TTTs prior to encapsulation to improve the moisture protection capabilities of the coatings. Leakage current measurements were made to evaluate the effect of applied monolayers on the moisture protection capability. The moisture protection capability was assessed in short-term and long-term leakage current measurements. MHDA (16-mercaptohexadecanoic acid) and APS (gamma-aminopropyltriethoxysilane) monolayers, in combination with silicone gel and epoxy resin respectively, exhibited very good moisture protection performance. 相似文献
179.
Use of microwaves for the synthesis and processing of materials 总被引:3,自引:0,他引:3
An overview of the synthesis of materials under microwave irradiation has been presented based on the work performed recently.
A variety of reactions such as direct combination, carbothermal reduction, carbidation and nitridation have been described.
Examples of microwave preparation of glasses are also presented. Great advantages of fast, clean and reduced reaction temperature
of microwave methods are emphasized. The example of ZrO2-CeO2 ceramics has been used to show the extraordinarily fast and effective sintering which occurs in microwave irradiation. 相似文献
180.
Ramesh M. Gohil 《应用聚合物科学杂志》1994,52(7):925-944
Morphology–property relationships for simultaneously biaxially stretched films and heatset with fixed dimensions in the temperature range of 100–240°C have been studied. The observed transition in various properties at 180°C can be explained on the basis of microstructural changes caused by competition among several processes, such as crystallization, solid-state thickening, melting, and molecular relaxation as well as by melting and recrystallization. The resulting structures and, thereby, the properties are different in temperature Regime-II (Tg to Tmax) and Regime-III (Tmax to Tm). In Regime-II, the high rate of crystallization compared to the rate of molecular relaxation develops a constrained amorphous phase, whereas the predominant melting and recrystallization process in Regime-III generates the relaxed amorphous phase. The structural reorganization during heat treatment is almost the same for uniaxially oriented film, fibers, and biaxially oriented films prepared under similar processing conditions. © 1994 John Wiley & Sons, Inc. 相似文献