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Atef W Idriss Mohammad S El‐Habbab 《Journal of the science of food and agriculture》2014,94(10):1922-1927
Food safety and quality assurance are increasingly a major issue with the globalisation of agricultural trade, on the one hand, and intensification of agriculture, on the other. Consumer protection has become a priority in policy‐making amongst the large economies of the Middle East and North Africa (MENA) countries following a number of food safety incidents. To enhance food safety, it is necessary to establish markets underpinned by knowledge and resources, including analysis of international rejections of food products from MENA countries, international laboratory accreditation, improved reporting systems and traceability, continued development and validation of analytical methods, and more work on correlating sensory evaluation with analytical results. MENA countries should develop a national strategy for food safety based on a holistic approach that extends from farm‐to‐fork and involves all the relevant stakeholders. Accordingly, food safety should be a regional programme, raising awareness among policy‐ and decision‐makers of the importance of food safety and quality for consumer protection, food trade and economic development. © 2014 Society of Chemical Industry 相似文献
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Flexible manufacturing cells (FMC) may be considered the most significant development in small-batch manufacturing. Setting-up and operating costs of FMC prove to be the most major hindrance to their large-scale implementation and use, particularly by small and medium size industries. Incompatibilities between the different components constituting the cells and the lack of a unified language/approach to programming and coordinating them are cited as the cause of the complexity of setting up and subsequently operating the cells. In order to eliminate these difficulties, a new philosophy for setting-up, programming and control of FMC has been developed. This paper reports the effort to develop this new unified manufacturing instruction set and its environment, called here “UniSet”, its philosophy and some of the components of the UniSet environment. UniSet has been developed as a non-exclusive unified manufacturing instruction set, based on comparisons of the prevailing machine tool and programming primitives. UniSet allows programmers to deal with only one instruction set, if they so desire, in a single coherent environment, rather than numerous machine programming languages. The software system is coded in an object-oriented programming (OOP) language, Smalltalk, and derives its paradigm from the OO philosophy. Test results are also included to demonstrate the applicability of the approach employed. 相似文献
45.
Adel Abdelrazek Abdelazim Mohdaly Mohamed Atef Sarhan Awad Mahmoud Mohamed Fawzy Ramadan Iryna Smetanska 《Food chemistry》2010
The antioxidant properties of potato peels and sugar beet pulp, in comparison with synthetic antioxidant, were investigated. The bioactive materials were extracted with methanol and examined for their antioxidant activity under accelerated oxidation conditions, using sunflower and soybean oils as oxidation substrates at different concentrations for 72 h at 70 °C. Inverse relationships were noted between peroxide values and oxidative stabilities and also between secondary oxidation products, measured by p-anisidine value and stabilities at termination of the storage. Absorptivity at 232 nm and 270 nm increased gradually with the increase in time, due to the formation of conjugated dienes and polyenes. The order of oxidative stability was as follow: TBHQ > potato peels > BHT = sugar beet pulp > BHA. The predominant phenolic compounds identified by thin-layer chromatography in potato peels and sugar beet pulp were chlorogenic and gallic acids. The results of different antioxidant parameters demonstrated that potato peels and sugar beet pulp are potent sources of natural antioxidants that might be explored to prevent oxidation of vegetable oils. 相似文献
46.
Several substituted titanates of formula Li4−xMgxTi5−xVxO12 (0 ≤ x ≤ 1) were synthesized (and investigated) as anode materials in rechargeable lithium batteries. Five samples labeled as S1–S5 were calcined (fired) at 900 °C for 10 h in air, and slowly cooled to room temperature in a tube furnace. The structural properties of the synthesized products have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transmission infrared (FTIR). XRD explained that the crystal structures of all samples were monoclinic while S1 and S3 were hexagonal. The morphology of the crystal of S1 was spherical while the other samples were prismatic in shape. SEM investigations explained that S4 had larger grain size diameter of 15–16 μm in comparison with the other samples. S4 sample had the highest conductivity 2.452 × 10−4 S cm−1. At a voltage plateau located at about 1.55 V (vs. Li +), S4 cell exhibited an initial specific discharge capacity of 198 mAh g−1. The results of cyclic voltammetry for Li4−xMgxTi5−xVxO12 showed that the electrochemical reaction was based on Ti4+/Ti3+ redox couple at potential range from 1.5 to 1.7 V. There is a pair of reversible redox peaks corresponding to the process of Li+ intercalation and de-intercalation in the Li–Ti–O oxides. 相似文献
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This research pertains to solar photovoltaic (PV) pumping for aeration of aquaculture ponds and evaluates it economically. A stand-alone photovoltaic aeration system based on recycling of water at 10 cm under the water surface, at the surface (0 cm) and above the surface (30 cm) on a perforated tray was evaluated. The effect of pump discharges (35, 50, 65 L/min) on standard oxygen transfer rate (SOTR) and standard aeration efficiency (SAE) was investigated. Results revealed that the daily averages of PV energy output, PV efficiency and load energy were 0.844 kWh/d, 9.87% and 0.615 kWh/d, respectively, at 65 L/min and 42.7°C PV temperature. Water flow upward at 30 cm over the perforated tray in the radial direction proved to be better since it gave an opportunity for the exchange of gaseous between the water and the atmosphere. The SOTR and SAE for the third position were 0.025 kgO2/h and 0.1 kgO2/kW h, respectively. 相似文献
48.
Radhouane Masmoudi Abdelmonem Masmoudi Mongi Ben Ouezdou Atef Daoud 《Construction and Building Materials》2011,25(2):486-493
Eighty pull-out specimens were used to study the effect of temperature ranging from 20 °C to 80 °C in dry environment on bond properties between Glass Fiber Reinforced Polymer (GFRP) bars and concrete. The pullout-test specimens were subjected during 4 and 8 months to high temperatures up to 80 °C and then compared to untreated specimens (20 °C). Experimental results showed no significant reduction on bond strength for temperatures up to 60 °C. However, a maximum of 14% reduction of the bond strength was observed for 80 °C temperature after 8 months of thermal loading. For treated specimens, the coefficient β in the CMR model, which predicts the bond–stress–displacement behavior, seems to be dependant with the temperature. 相似文献
49.
An acid dyeable acrylic fabric has been obtained by the pretreatment with cationic aqueous polyurethane, containing different amounts of quaternary nitrogen. Cationic polyurethane has the ability to interact with the carboxylic groups in the acrylic fabrics, as well as providing basic sites suitable for acid dyeing. The prepared polyurethane has been identified with FTIR, and the effect of the pretreatment conditions on the dyeability and printability of the fabrics has been investigated. The color strength values and the fastness properties of the dyed and printed samples, reveal the ionic interaction between the sulphonic groups in the acid dye molecules and the quaternary nitrogen on the fabrics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
50.
Four different Aspergilli (Aspergillus oryzae, A. parasiticus, A. terreus and A. versicolor) were grown on wheat grains underdifferent degrees of relative humidity 14, 50, 74, 80 and 90%. Samples of wheat grains were taken monthly for a period of six months and examined for mycotoxin production. A. oryzae was found to produce aflatoxins B1, B2, zearalenone, DON and T-2 toxins under elevated degrees of humidity and prolonged periods of storage. A. parasiticus produced aflatoxins B1, G1, NIV, DON and T-2 toxins in high concentrations during a period of not more than three months storage at 14% relative humidity; at an increased level of relative humidity of 74% ochratoxin A, zearalenone and sterigmatocystin were also produced at high levels. The isolate was drastic in toxin production. A. terrus produced toxins at 14% relative humidity (aflatoxin G2 and DON) at levels much higher than any other prevalent degrees of humidity. A. versicolor is highly sensitive to relative humidity and grain moisture content It produced aflatoxins B1, G1, NIV and DON at a relative humidity of 50% and another toxins (aflatoxin G2, ochratoxins A, B and zearalenone) at 74%. The microorganism can be considered a trichothecene producer under suitable relative humidity. 相似文献