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排序方式: 共有833条查询结果,搜索用时 281 毫秒
91.
Konstantina Lambrinou Wout Maurissen Paresh Limaye Bart Vandevelde Bert Verlinden Ingrid De Wolf 《Journal of Electronic Materials》2009,38(9):1881-1895
This work addresses a new mode of brittle failure that occurs in the bulk of tin-based lead-free solder joints, unlike the
typical brittle failures that occur in the interfacial intermetallics. Brittle failures in the joint bulk result from the
low-temperature ductile-to-brittle transition in the fracture behavior of β-tin. The bulk embrittlement of these joints is
discussed by referring to the results of impact tests performed on both solder joints and bulk solder specimens. The mechanism
of bulk embrittlement is largely explained based on the results of a fractography study performed on the bulk joint failures
using scanning electron microscopy. 相似文献
92.
Charles M.A.P. Franz Ingrid Specht Gyu-Sung Cho Volker Graef Mario R. Stahl 《Food Control》2009,20(12):1103-1107
A novel UV-C irradiation device in laboratory scale was tested for its potential to inactivate bacteria in naturally cloudy apple juice. In this device, liquid flows through a helically wound tubing wrapped around a quartz glass tube containing a 9 W UV lamp with an irradiation intensity of 60 W/m2 at 254 nm. The equipment was capable of reducing numbers of inoculated Escherichia coli and Lactobacillus brevis from an initial concentration of approximately 106 CFU/ml or 104 CFU/ml to below detectable limits in commercial naturally cloudy apple juice at a flow rate of 2 l/h, and to well below 1 × 102 also at higher flow rates of 4 and 8 l/h. Numbers of Saccharomyces cerevisiae could be reduced from an initial level of ca. 1 × 104–1 × 102 CFU/ml or less at flow rates of 2 and 4 l/h. Although E. coli could be effectively inactivated also in self-extracted, as well as industrially processed apple juice, contaminating yeast and lactic acid bacteria were not completely eliminated. 相似文献
93.
94.
Ingrid Aguil-Aguayo ngel Sobrino-Lpez Robert Soliva-Fortuny Olga Martín-Belloso 《Innovative Food Science and Emerging Technologies》2008,9(4):455-462
The influence of high-intensity pulsed electric field (HIPEF) parameters, pulse frequency, pulse width and pulse polarity in strawberry juice lipoxygenase (LOX) and β-glucosidase (β-GLUC) was studied using a response surface methodology. The studied parameters affected on both residual enzymatic activities at unchanging electric field strength of 35 kV/cm and treatment time for 1000 μs. The contour plots showed a minimum defined space where residual activity of LOX remained at 65% and 70% in monopolar and bipolar mode, respectively. Low pulse frequencies (up to 61.6 Hz) in monopolar treatments as well as pulse frequencies and widths higher than 218 Hz and 5.4 μs in bipolar treatments did not have any effect on LOX inactivation. On the other hand, the higher the pulse frequency and pulse width, the higher the β-GLUC inactivation obtained. Moreover, when the HIPEF treatment was applied in monopolar mode, an enhancement in β-GLUC activity was observed in most of the experimental range. HIPEF treatments have demonstrated adequately that can reduce activity of enzymes that are involved in the formation of desirable flavor compounds, helping processors to obtain juices that keep their fresh flavor.
Industrial relevance
High-intensity pulsed electric fields (HIPEF) have proved to be effective in the interaction of microorganisms and enzymes in juices, maintaining their quality and freshness.HIPEF juice processing has demonstrated to have some advantages with regard to conventional thermal treatment. HIPEF treatments can reduce adequately enzymes that are involved in the formation of desirable flavor or color compounds. Thus, HIPEF technology can help processors to obtain juices that keep their fresh flavor by achieving optimal inactivation of related enzymes. This would prevent the product from undesirable off-flavor formation, which in turn would result in greater acceptability by consumers. 相似文献95.
Ingrid Lessa Leal Yasmin Carolino da Silva Rosa Josenai da Silva Penha Paulo Romano Cruz Correia Pollyana da Silva Melo Danilo Hansen Guimarães Josiane Dantas Viana Barbosa Janice Izabel Druzian Bruna Aparecida Souza Machado 《应用聚合物科学杂志》2019,136(43):48150
In this study, formulations of cassava starch and poly(butylene adipate-co-terephthalate) flexible films were developed, with glycerol, coconut nanocellulose, annatto, and citric acid in different concentrations, as well as the effectiveness of the selected materials in fresh-cut mangoes storage was evaluated. The tensile strength of the different formulations varied from 1.90 (E4) to 6.65 MPa (E3c), and the strain varied from 206.31 (E1c) to 278.41% (E8); this variation was dependent on the percentage of the polymer matrix incorporated. The aw values of the formulations ranged from 0.396 (E2) to 0.569 (E3c). The Formulations E4 and E7 (with additives) presented good properties and were selected to condition mangoes. The micrographs of these films showed regions of micropores that can facilitate the diffusion of water from the packaged product to the surface, allowing decreases in moisture and aw, which is associated with higher color maintenance during fruit storage. E7 presented better barrier properties than E4 (lower values of WVP and water solubility) which may have influenced in a positive way to maintain the stability of the package in the studied period. E7 can be considered as a viable alternative for minimally processed mango storage. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48150. 相似文献
96.
Ingrid D. Santaren Richard P. Bazinet Zhen Liu Luke W. Johnston John L. Sievenpiper Adria Giacca Ravi Retnakaran Stewart B. Harris Bernard Zinman Anthony J. Hanley 《Lipids》2019,54(10):617-627
Circulating fatty acids (FA) derived largely from dairy consumption have most commonly been measured in total human serum or phospholipid (PL) fractions, and have been used as validated biomarkers of dairy intake in a growing number of epidemiological studies. Nevertheless, measurement and characterization of a wider spectrum of FA biomarkers of dairy across the four major serum lipid fractions is lacking. This study aimed to (1) quantify FA biomarkers of dairy in PL, triacylglycerol (TAG), cholesteryl ester (CE), and unesterified fatty acid (FFA) serum lipid fractions; and (2) identify potential demographic and metabolic factors that may modify the proportions of these FA across serum fractions. Baseline data from 444 adults in the PROMISE cohort were analyzed. FA biomarkers, 15:0, t16:1n-7, 18:2-c9,t11, and t18:1n-7 were quantified from serum. Dairy intake was estimated using the validated Canadian Diet History Questionnaire. Our results show that t18:1n-7 was the most abundant FA biomarker in all fractions except CE, where 18:2-c9,t11 was the most abundant. Positive correlations within fractions, and across FA in the PL, CE, and FFA fractions were found, however, TAG FA were negatively correlated with the other fractions. PL and CE FA were positively associated with dairy intake, and negatively associated with markers of dysmetabolism while, in contrast, these markers were predictors of higher TAG dairy FA. This study is the first to demonstrate distinct proportions of dairy FA in different serum lipid fractions. PL and CE FA marked dairy intake in this cohort, while TAG FA appeared to be markers of dysmetabolism. 相似文献
97.
Docherty KS Stone EA Ulbrich IM DeCarlo PF Snyder DC Schauer JJ Peltier RE Weber RJ Murphy SM Seinfeld JH Grover BD Eatough DJ Jimenez JL 《Environmental science & technology》2008,42(20):7655-7662
Ambient sampling was conducted in Riverside, California during the 2005 Study of Organic Aerosols in Riverside to characterize the composition and sources of organic aerosol using a variety of state-of-the-art instrumentation and source apportionmenttechniques. The secondary organic aerosol (SOA) mass is estimated by elemental carbon and carbon monoxide tracer methods, water soluble organic carbon content, chemical mass balance of organic molecular markers, and positive matrix factorization of high-resolution aerosol mass spectrometer data. Estimates obtained from each ofthese methods indicate that the organic fraction in ambient aerosol is overwhelmingly secondary in nature during a period of several weeks with moderate ozone concentrations and that SOA is the single largest component of PM1 aerosol in Riverside. Average SOA/OA contributions of 70-90% were observed during midday periods, whereas minimum SOA contributions of approximately 45% were observed during peak morning traffic periods. These results are contraryto previous estimates of SOAthroughout the Los Angeles Basin which reported that, other than during severe photochemical smog episodes, SOA was lower than primary OA. Possible reasons for these differences are discussed. 相似文献
98.
99.
Tomás Lafarga Silvia Villaró Gloria Bobo Joan Simó Ingrid Aguiló-Aguayo 《International Journal of Food Science & Technology》2019,54(5):1816-1823
The aim of this study was to evaluate the bioaccessibility of polyphenols and antioxidant activity in cooked pulses and to study the effect of cooking on their total phenolic content (TPC) and antioxidant capacity. Cooked faba beans showed the highest TPC, followed by soybeans and lentils or peas. TPC ranged from 10.4 ± 0.2 to 52.9 ± 0.3 mg/100 g and was positively correlated with antioxidant activity. Cooking resulted in increased TPC and antioxidant activity of the methanolic extracts, caused by cell disruption and improved extraction of polyphenols. Although polyphenols were lost in the cooking water, boiled legumes had more polyphenols than those resulting cooking broths. In vitro gastrointestinal digestion resulted in increased TPC and antioxidant capacity of the extracts. Soybeans showed the highest amount of bioaccessible polyphenols. The release of phenolics from cooked legumes was mainly achieved during the intestinal phase. Literature data may underestimate the TPC and antioxidant capacity of pulses. 相似文献
100.
Giuseppina Luzzi Marco Steffens Ingrid Clawin‐Rdecker Wolfgang Hoffmann Charles M A P Franz Jan Fritsche Peter Chr Lorenzen 《International Journal of Dairy Technology》2020,73(3):502-512
Lactose solutions of up to 50% (w/v) were incubated with lactases and glucose isomerases for subsequent implementation in dairy product samples to enhance sweetness. A degree of hydrolysis of >90% and of isomerisation of 50% were attainable. The sensory sweetening power of lactose in solutions of up to 50% (w/v) can be enhanced 2–3 times. Based on sensory experiments, application of this bi‐enzymatic system in yoghurt and pudding samples allowed for a 10–20% (w/w) reduction in the total sugar content, whilst retaining equal sweetness. The growth of yoghurt starter cultures was not affected, yet furosine formation more than doubled in high heated, enzyme‐modified milk. 相似文献