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The use of cheese whey and probiotic cultures in the production of dairy beverages has been highly attractive; nonetheless, whey-based goat beverages tend to be poor and watery when compared to fermented milks. The addition of fruits and fibre ingredients might improve texture and mouthfeel of this kind of product. Fermented whey-based goat beverages prepared using Streptococcus thermophilus TA-40 as starter culture, with added guava or soursop pulps, and with or without addition of partially hydrolysed galactomannan from Caesalpinia pulcherrima seeds (PHGM), showed to be good vehicles for Bifidobacterium animalis subsp. lactis BB-12 and Lactobacillus rhamnosus Lr-32, maintaining their viability above 7 log CFU/ml during 21 days. PHGM increased the dietary fibre content and enhanced the instrumental texture and sensory features of both guava and soursop dairy beverages, especially texture, appearance, and overall acceptability. The PHGM might be recommended to improve nutritional and sensory quality of fermented probiotic beverages produced with goat milk and cheese whey. 相似文献
74.
C��ssio L. Rodrigues Karina R. G. da Silva Henrique N. Cunha Jorge C. A. de Figueiredo Dalton D. S. Guerrero Elmar Melcher 《Design Automation for Embedded Systems》2011,15(3-4):225-245
During the functional verification, complex interactions between multiple blocks that compose an Intellectual Property (IP) core can reveal hard-to-find bugs. Functional verification specifications must be precise to assure these interactions occur during the simulation. In this work, we are proposing a technique for improving the functional verification specification of individual blocks, preserving the occurrence of these interaction scenarios in the composition phase. Our approach was implemented for the VeriSC methodology, a SystemC-based functional verification methodology. After each block that composes the IP core was stand-alone verified, we exploit the composition phase using set theory to increase the coverage numbers and to justify why some of these numbers cannot, or need not, reach 100%. By applying our approach in a MPEG 4 video decoder design, we show how our work can save functional verification time during the hierarchical composition. Using mutation based-tests, we demonstrate that our work can contribute to error detection. Furthermore, we demonstrate the effectiveness of our approach with regard to traditional structural coverage metrics, such as line coverage and branch coverage. 相似文献
75.
Sampaio KL Garruti DS Franco MR Janzantti NS Da Silva MA 《Journal of the science of food and agriculture》2011,91(10):1801-1809
BACKGROUND: There is a considerable loss of volatile compounds during the thermal concentration of cashew apple juice, damaging product quality, and as yet there is little research on the subject. Thus the purpose of this research was to identify the aroma volatiles evaporated off from cashew apple juice and recovered in the water phase during concentration of this beverage in an industrial plant. Water phase volatiles were extracted using dichloromethane, concentrated under a nitrogen flow, separated by gas chromatography (GC) and identified by GC‐mass spectrometry. In order to determine the contribution of each volatile to the cashew aroma, five trained judges evaluated the GC effluents using the Osme GC‐olfactometry technique. RESULTS: 71 volatiles were identified; of these, 47 were odour active. Alcohols were preferentially recovered in the cashew water phase, notably heptanol, trans ‐3‐hexen‐1‐ol and 3‐methyl‐1‐butanol, representing 42% of the total chromatogram area and imparting green grass and fruity aroma notes to the water phase. Esters represented 21% of the total chromatogram area, especially ethyl 2‐hydroxyhexanoate, ethyl trans ‐2‐butenoate and ethyl 2‐methylbutanoate, and were responsible for the fruity/cashew‐like aroma of the water phase. On the other hand, 3‐methylbutanoic and 2‐methylbutanoic acids were the volatiles that presented the greatest odour impact in the GC effluents of the water phase. CONCLUSION: Overall, the results of the present study strongly indicated that further concentration of the esters recovered in the water phase, either by partial distillation or by alternative technologies such as pervaporation, could generate a higher‐quality natural cashew apple essence. Copyright © 2011 Society of Chemical Industry 相似文献
76.
The effect of thermal treatment on the catalyst structure and the CO oxidation performance of a Au/TiO2 catalyst supported on a carbon composite material has been studied. X-ray absorption spectroscopy shows that the carbon composite stabilises the TiO2 and prevent agglomeration of the particles. The activity measurements show that both Au and TiO2 need to be present in order to obtain catalytic activity. The catalytic performance was found to be strongly affected by thermal treatments of the active phase prior to the reaction. The thermal treatments have an effect on the ordering of the TiO2 structure, and on the CO oxidation activity. Heat treatment after Au deposition has a positive effect on the CO oxidation performance. This is attributed to the introduction of a stronger interaction between the oxide and Au which improves the catalytic activity. This also indicates that the TiO2 support and the Au–TiO2 interface play important roles in the CO oxidation reaction. 相似文献
77.
Rodrigo Araya Karina Araus Khriscia Utria Mario Toledo 《International Journal of Hydrogen Energy》2014
The effect of adding steam during filtration combustion of natural gas–air mixtures was studied with the aim to evaluate the optimization of hydrogen production. Temperature, velocity, chemical products of combustion waves, and conversion from fuel to H2 and CO were evaluated in the range of equivalence ratio (φ) from stoichiometric (φ = 1.0) to φ = 3.0 and steam content in the mixture from 0% to 39%, at filtration velocities from 12 to 25 cm/s. Numerical simulation was carried out using GRI-MECH 3.0. Results suggest that H2 and CO concentrations, dominant for rich and ultrarich combustion, are products from partial oxidation and steam natural gas reforming processes. Experimental and numerical results show that hydrogen yield increase with an increase of steam content in the natural gas–air mixtures. 相似文献
78.
A common method for the production of hydrogen and syngas is solid fuel gasification. This paper discusses the experimental results obtained from the combustion of lean natural gas–air mixtures in a porous medium composed of aleatory alumina spheres and wood pellets, called hybrid bed. Temperature, velocity, and chemical products (H2, CO, CO2, CH4) of the combustion waves were recorded experimentally in an inert bed (baseline) and hybrid bed (with a volume wood fraction of 50%), for equivalence ratios (φ) from 0.3 to 1.0, and a constant filtration velocity of 15 cm/s. Upstream, downstream and standing combustion waves were observed for inert and hybrid bed. The maximum hydrogen conversion in hybrid filtration combustion is found to be ∼99% at φ = 0.3. Results demonstrate that wood gasification process occurs with high temperature (1188 K) and oxygen available, and the lean hybrid filtration process can be used to reform solid fuels into hydrogen and syngas. 相似文献
79.
Virginia Melo-Ruiz Yomas Quirino-Barreda Concepcion Calvo-Carrillo Karina Sanchez-Herrera Horacio Sandoval-Trujillo 《化学与化工:英文版》2013,(12):1181-1187
Edible insects, escamoles ant eggs of the Formicidae family are consumed by cultural tradition at rural communities and by sensory characteristics at high class restaurants of Mexico; however, people ignore the importance of insect consumption in the nutrition of humans. Laboratory spectroscopy methods in food analysis represent benefits in time and precision. The aim of this study is to assess macronutrients and micronutrients of escamoles and eggs by spectroscopic methods to inform population the benefits they provide in health and to mention the advantage in the use of these techniques at laboratory work. Samples were gather the second week of March and April 2012, at Hidalgo State and analyze moisture and macronutrients by AOAC (Association of Official Analytical Chemistry) methods, amino acids by cation exchange chromatography, tryptophan was determined by a colorimeter method, fatty acids by GC (gas chromatography) using helium as a carrier (AOAC), fat soluble vitamins A, D and E by HPLC (high performance liquid chromatography), and minerals by atomic absorption spectrophotometers and phosphorus by colorimeter (AOAC). Data showed high amount in proteins, lipids and minerals; low in fiber and soluble carbohydrates; contained all essential amino acids. Fatty acids contain monounsaturated and polyunsaturated. Fat soluble vitamins A, D and E. Minerals: sodium, phosphorus, potassium, magnesium, calcium and manganese. Escamoles ant eggs include polyunsaturated fatty acids essential for mental development, vitamin A to prevent eye diseases, vitamin E as antioxidant and vitamin D involved in calcium absorption that low intake, impair grow and bone health. Iron and zinc contained anemia. Regarding the laboratory benefits, needs less expensive chemicals, testing is clean, rapid and easy results of multiple samples, but it is required to handle by qualified chemists. In conclusion, data may change according to biotic and abiotic conditions of the environment; however, escamoles have all nutrients in adequate balance to improve human health; and provide faster and precise results. 相似文献
80.
Antonio Vega-Gálvez Kong Ah-HenMarcelo Chacana Judith VergaraJavier Martínez-Monzó Purificación García-SegoviaRoberto Lemus-Mondaca Karina Di Scala 《Food chemistry》2012,132(1):51-59
The aim of this work was to study the effect of temperature and air velocity on the drying kinetics and quality attributes of apple (var. Granny Smith) slices during drying. Experiments were conducted at 40, 60 and 80 °C, as well as at air velocities of 0.5, 1.0 and 1.5 m s−1. Effective moisture diffusivity increased with temperature and air velocity, reaching a value of 15.30 × 10−9 m2 s−1 at maximum temperature and air velocity under study. The rehydration ratio changed with varying both air velocity and temperature indicating tissue damage due to processing. The colour difference, ΔE, showed the best results at 80 °C. The DPPH-radical scavenging activity at 40 °C and 0.5 m s−1 showed the highest antioxidant activity, closest to that of the fresh sample. Although ΔE decreased with temperature, antioxidant activity barely varied and even increased at high air velocities, revealing an antioxidant capacity of the browning products. The total phenolics decreased with temperature, but at high air velocity retardation of thermal degradation was observed. Firmness was also determined and explained using glass transition concept and microstructure analysis. 相似文献