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901.
Osman Sagdic Ismet Ozturk Hasan Cankurt Fatih Tornuk 《Food and Bioprocess Technology》2012,5(8):2964-2971
In this study, effect of ellagic acid (EA), gallic acid (GA), grape seed extract (GSE), pomegranate peel extract (PPE), and peppermint essential oil (PEO) supplementation on sensorial and antioxidative properties of ice cream was determined. Additionally, survival of Lactobacillus casei Shirota in ice cream and its interaction with the supplements were also investigated. All the supplements increased total phenolic content of ice creams significantly (P?<?0.05). DPPH radical scavenging activities of ice creams supplemented with EA, GA, PPE, or GSE were higher than that of control group. Moreover, PPE made the best contribution to phenolic content and antiradical activity of ice cream. L. casei Shirota was highly adapted to ice cream media and survived with high numbers (7.21?log?cfu/mL) during the storage period for 60?days. Supplementation of ice creams provided lower decrease in bacterial number, and the best bacterial behaviors were observed in the ice creams supplemented with GA or PPE. All ice cream samples tested in this study had generally acceptable sensorial scores. In conclusion, EA, GA, PPE, GSE, and PEO could be used to enhance the phenolic content of ice cream and to gain antioxidant property, and there was a good interaction between L. casei and these phenolic compounds. Additionally, PPE supplementation provided the best result for all concerns. 相似文献
902.
The effects of two irradiation doses (2.5 and 5 kGy) on nucleotide breakdown compounds in sea bass stored in ice were investigated. Nucleotide degradation was slower in sea bass irradiated at 2.5 and 5 kGy than untreated samples. Irradiated samples had lower hypoxanthine and inosine content than the control group. Significant differences (p < 0.05) in K and related values were found between control groups and irradiated samples (2.5 and 5 kGy). H and G values showed a good correlation with storage time (r2 ? 0.98) while linear regressions of K and Ki ranged from 0.95 and 0.93 to 0.98 and 0.97, respectively. A dose of 5 kGy seemed to be more effective than that of 2.5 kGy to reduce nucleotide breakdown in sea bass. The best linear correlation was obtained from G and H values; thus, they might be used as freshness indicators for non-irradiated and irradiated sea bass. 相似文献
903.
Bishnoi SW Rozell CJ Levin CS Gheith MK Johnson BR Johnson DH Halas NJ 《Nano letters》2006,6(8):1687-1692
We show that an Au nanoshell with a pH-sensitive molecular adsorbate functions as a standalone, all-optical nanoscale pH meter that monitors its local environment through the pH-dependent surface-enhanced Raman scattering (SERS) spectra of the adsorbate molecules. Moreover, we also show how the performance of such a functional nanodevice can be assessed quantitatively. The complex spectral output is reduced to a simple device characteristic by application of a locally linear manifold approximation algorithm. The average accuracy of the nano-"meter" was found to be +/-0.10 pH units across its operating range. 相似文献
904.
Vallhov H Qin J Johansson SM Ahlborg N Muhammed MA Scheynius A Gabrielsson S 《Nano letters》2006,6(8):1682-1686
We investigated the effect of spherical gold nanoparticles on immature dendritic cells (DCs). Conventionally produced nanoparticles had a maturating effect on the DCs--a result of lipopolysaccharide (LPS) contamination. By modification of the production process, low-LPS particles were obtained, which had practically no effect on phenotypic maturation or cytokine production of the DCs. Our findings emphasize the importance of high purity in the production of nanoparticles, since possible contaminants may interfere with the assessment of biological/medical effects. They also highlight that nanoparticles can function as carriers of immune modulating contaminants. 相似文献
905.
Fatih Onur Hocaoğlu Ömer Nezih Gerek Mehmet Kurban 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(8-9):472-481
Modeling the wind speed data has important implications in wind studies, providing valuable insight and parametric quantities for further engineering analysis. The classical modeling approach is to fit the probability distribution to a known model and estimate statistical parameters like mean and variance. Such models lack the time variation properties and ignore cross-dependencies between other meteorological data. In this paper a procedure is developed to model the wind speed data using a dependent process of atmospheric pressure in the form of hidden Markov models (HMMs). Consequently, the inherent dependencies between the wind speed and pressure are exploited. HMMs relate the two quantities in a framework which eliminates the necessity of direct sample-wise correlations, and avoid direct time-series analysis complications of the stochastic wind speed data at a marginal expense of easy pressure measurements. The experimental data were obtained from recordings of hourly atmospheric pressure and wind speed values for two cities in Turkey, namely Izmir and Kayseri. Model details and numerical results are presented. 相似文献
906.
The aim of this paper is to perform an exploratory spatial data analysis on the growth and development level of the 76 Turkish regions over 1995–2001. While our choropleth maps indicate that the Western part of the country is significantly more developed than the East, the tools of spatial statistics reveal the presence of spatial dependence across provinces. The presence of heterogeneity is reflected in the distribution of Local Indicators of Spatial Association statistics. Overall, our results shed new light on the distribution of growth across Turkish regions and its relation with public investments and human capital, two indicators of development. 相似文献
907.
This work determines quality properties and fatty acids content of Nile tilapia (Oreochromis niloticus) stored in ice for 21 d. The quality properties consist of thiobarbituic acid (TBA), total volatile basic nitrogen (TVB‐N), trimethylamine (TMA), and microbiological analysis (total viable count (TVC), total coliform, Salmonella and Staphylococcus aureus) and determination of biogenic amines content (histamine, cadaverine, putrescine, spermine, spermidine, 2‐phenylethylamine, agmatine, tyramine, and ammonia). Moreover, the fat, moisture, and ash composition as well as fatty acids profile have also been analyzed. The TBA, TVB‐N, and biogenic amines analysis showed rather low levels of spoilage even after 21 d of storage. The microbiological analysis, however, showed that tilapia was unsuitable for consumption after just 10 d. The fat, ash, moisture, and fatty acids profile analysis showed that tilapia is not a good source of n?3 fatty acids. The research indicated that the microbiological analysis was the best method to establish spoilage of tilapia stored in ice, of all analytical methods performed in this study. 相似文献
908.
Mustafa Umit Irkilmez Mehmet Başlar Osman Sağdiç Muhammet Arici Mustafa Fatih Ertugay 《Sensing and Instrumentation for Food Quality and Safety》2017,11(2):380-387
This study examined the effects of ultrasound on several quality parameters of plum nectars, such as turbidity, microbial load, PPO activity, phenolic content, and physicochemical quality. The ultrasonic treatment was applied to the plum nectars at different treatment temperatures (40, 50, 60, and 70?°C) and durations (2.5, 5, 7.5, and 10 min). Ultrasound processing caused a significant increase in the turbidity level and stability of the plum nectars, which were correlated with increases in treatment temperature and duration. Similar effects were also observed in reduction of microbial load. Ultrasonic treatments at 7.5 min at 60?°C and 5 min at 70?°C reduced the total yeast and mold counts (<?1 log cfu/mL). The total mesophilic-aerobic microorganism (TMAB) count was also reduced by up to 2 log. The maximum inactivation of polyphenol oxidase (PPO) was ~46?% at 70?°C. No dramatic trends were observed for the pH, brix, and the total phenolic compound content of the plum nectar, while the flavonoid content dramatically increased. The ultrasonic treatment caused a slight positive color change by increasing the L* value of the plum nectars. In conclusion, the ultrasonic treatment was important process for increasing the turbidity quality and for inactivation of yeasts and molds, but it was not effective at inactivating the PPO enzyme. 相似文献
909.
A study of removal of Copper and Zinc from acidic mine effluents by means of chelating ion exchange resins has been carried out. The effluents having pH ranging from 1.7 to 1.9, contain mainly iron, copper and zinc and some other elements at much lower concentrations. The study includes chemical characterisation of effluents samples, the assessment of chelating resins and their selectivity for the separation of copper and zinc. Chelating resins containing either carboxylic, phosphoric or/and amine groups have been employed. The results obtained are correlated to the specific metal-complexing group attached to the polymer matrix. Resins containing carboxylate groups were found to provide most selective copper/zinc separations. A conceptual flowsheet of the separation process based on the data obtained for treating the effluents with different resins is presented. 相似文献
910.
Lindokuhle Precious Magagula Clinton Michael Masemola Muhammed Asad Ballim Zikhona Nobuntu Tetana Nosipho Moloto Ella Cebisa Linganiso 《International journal of molecular sciences》2022,23(8)
Rapid population and economic growth, excessive use of fossil fuels, and climate change have contributed to a serious turn towards environmental management and sustainability. The agricultural sector is a big contributor to (lignocellulosic) waste, which accumulates in landfills and ultimately gets burned, polluting the environment. In response to the current climate-change crisis, policymakers and researchers are, respectively, encouraging and seeking ways of creating value-added products from generated waste. Recently, agricultural waste has been regularly appearing in articles communicating the production of a range of carbon and polymeric materials worldwide. The extraction of cellulose nanocrystals (CNCs) and carbon quantum dots (CQDs) from biomass waste partially occupies some of the waste-recycling and management space. Further, the new materials generated from this waste promise to be effective and competitive in emerging markets. This short review summarizes recent work in the area of CNCs and CQDs synthesised from biomass waste. Synthesis methods, properties, and prospective application of these materials are summarized. Current challenges and the benefits of using biomass waste are also discussed. 相似文献