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81.
Since vitamin A deficiency is prevalent in many developing countries, we sought to focus research on local, affordable and well-accepted sources of provitamin A carotenoids. As dessert bananas are consumed fresh round the year and processed as products, this study investigated whether post-climacteric biochemical changes are linked to carotenoid degradation in four Indian varieties, one commercial (Cavendish, AAA), one Red banana (genome AAA) and two locally-important ones (genome AAB). Despite large differences in their ripening characteristics, textural loss was lesser in AABs than AAAs. High levels of carotenoids (21.0 μg/g FW), β-carotene (9.14 μg/g FW) and α-carotene (9.32 μg/g FW) were found in Red banana accounting for retinol activity equivalent of 114 μg/100 g FW. The carotenoid levels were lower in two local varieties and lowest in Cavendish, with no post-climacteric loss. Dry grits, prepared using Red banana pulp, milk powder and sugar, retained about 70% carotenoids and appeared useful in confectionaries.  相似文献   
82.
Amorphous silicon oxycarbides are known to be an effective anode material for lithium-ion batteries. Despite their exceptional properties and high charge capacities, however, their practical uses are limited by their significant first-cycle loss, considerable hysteresis, and low cyclic ability. Comparatively, SiOC/metal oxide materials have demonstrated increased rate capability and cyclic stability. This study utilized a liquid precursor-derived ceramic method to modify SiOC with titanium (IV) butoxide precursor to synthesize SiOC/TiOxCy. X-ray diffractograms confirmed the amorphous nature of SiOC/TiOxCy. The elemental composition and bonding properties were investigated using X-ray photoelectron spectroscopy, and electron microscopy was used to explore morphological features. In the first cycle, the reversible capacity of pyrolyzed SiOC/TiOxCy was 520 mAh g−1, which then increased to 736 mAh g−1 for the 1200°C annealed SiOC/TiOxCy due to the increased free carbon network and TiC conductive phases. The irreversible capacity of the first cycle was 568 mAh g−1, which was lower than the annealed SiOC irreversible capacity of 695 mAh g−1. Interestingly, the rate stability of the pyrolyzed SiOC/TiOxCy performed more stability than the annealed sample. Localized carbothermal reactions between amorphous SiOC/TiOxCy and free carbon at annealing temperatures resulted in loss of structure stability.  相似文献   
83.
The biotransformation potential of six nitrosamines and their precursor secondary amines by a mixed methanogenic culture was investigated. Among the six nitrosamines tested, N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), and N-nitrosopyrrolidine (NPYR) were almost completely degraded but only when degradable electron donors were available. On the contrary, N-nitrosodiethylamine (NDEA), N-nitrosodipropylamine (NDPA), and N-nitrosodibutylamine (NDBA) were not degraded. Three precursor secondary amines, corresponding to the three biodegradable nitrosamines, were also completely utilized even with very low levels of available electron donors. The secondary amine precursors of the three, nonbiodegradable nitrosamines were also recalcitrant. A bioassay conducted to elucidate the biotransformation pathway of NDMA in the mixed methanogenic culture using H(2) as the electron donor showed that NDMA was utilized as an electron acceptor and transformed to dimethylamine (DMA), which in turn was degraded to ammonia and methane. The H(2) threshold concentration for NDMA bioreduction ranged between 0.0017 and 0.031 atm. Such a high H(2) threshold concentration suggests that in mixed methanogenic cultures, NDMA reducers are weak competitors to other, H(2)-consuming microbial species, such as homoacetogens and methanogens. Thus, complete removal of nitrosamines in anaerobic digestion systems, where the H(2) partial pressure is typically below 10(-4) atm, is difficult to achieve.  相似文献   
84.
Maleated bitumen was prepared by the reaction of penetration grade bitumen (80/100) with maleic anhydride at 150°C for 2 h under nitrogen atmosphere. The effectiveness of maleation was assessed in bitumen–recycled low‐density polyethylene (LDPE) blends in terms of their softening point and elastic recovery. It was observed that the softening point and elastic recovery of the blends increased after maleation of the base bitumen owing to the formation of an asphaltene‐linked‐LDPE system. To obtain the desired elasticity, a recoverable composition was worked out with the help of maleated bitumen, recycled LDPE and styrene–butadiene–styrene. The storage stability of the blends was assessed in terms of their difference in softening points, rheological parameters, and microstructure of the top and bottom portions of test tube samples. The difference in softening point of the recoverable maleated bitumen blend was 5°C as compared to 60°C for the base bitumen blend. The phase angle was also reduced to 7.4° at 70°C compared with the 44.30° for the base bitumen blend. Scanning electron micrographs indicate that polymers existed in both the top and the bottom portions of the aged test tube maleated blend samples. The stability of the blend was further improved when LDPE is colloidal milled with maleic anhydride in the blend preparation. Roofing bitumen was also made with maleated bitumen containing 9 wt % recycled LDPE content. Based on the rheological data, it was found that the maleated bitumen–LDPE blend exhibited superior time‐/temperature‐dependent response and higher creep recovery compared with the base bitumen blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013  相似文献   
85.
Sintering behavior of nano-sized titanium diboride (TiB2) powder prepared by a self-propagating high-temperature synthesis (SHS) technique was compared with that of the commercially available powder. The SHS-made powder showed excellent sinterability at low temperatures and a maximum of 97% densification was achieved at 2223 K, whereas the identically sintered commercial powder could only be densified to ∼86% at 2223 K. The estimated activation energies for sintering of 35±0.07 kJ/mole and 46±0.7 kJ/mole for the SHS and commercial powder, respectively, indicated the possibility of a different mechanism during sintering.  相似文献   
86.
Compared to other vegetable oils, rice bran oil (RBO) has a characteristic dark color which further deepens upon heating or frying of foods in the oil. Darkening of the oil during heating has been studied. The dark color‐causing material in crude, chemically refined and physically refined rice bran oils was separated using a silica gel column for a hexane‐eluted oil fraction and a methanol eluted fraction. The methanol eluted fraction for all the above three types of RBO produced a dark color upon heating, hence the physically refined RBO methanol fraction was investigated further and contained monoglycerides (23.4 %) and diglycerides (67.4 %) of linoleic + linolenic acids in its methanol fraction as analyzed by column chromatography and HPLC which decreased in concentration after heating. The linoleic acid level of 37.7 % in the methanol fraction was reduced significantly to 18 % after heating (52.3 % reduction). The IR and NMR spectra were similar to those of a monoglyceride/diglyceride with NMR spectra indicating a lower amount of olefinic protons for the heated sample. These results showed that the darkening of RBO was due to the oxidation and polymerization of monoglycerides/diglycerides containing linoleic acid/linolenic acid.  相似文献   
87.
Indian economy includes the major contribution provided by agriculturally driven activities. There is need to provide the agricultural stakeholders an appropriate, reliable, local, fast, ‘round-the-clock, and precise knowledge, possibly in their native language, in order that they can enhance their decision-making capacity to improve the agricultural productivity. This can be achieved by using mobile phones. Mobile phones are becoming part of the daily routine of farmers and can be used to disseminate this appropriate, multilingual, localized knowledge right at the location of use. In this article, an improved fuzzy rule promotion-based technique to infer advice to farmers has been presented. Using this technique, an Android-based mobile phone application named mAgIDS has been developed. This application uses a Global Positioning System (GPS) for localized inference and local language selected by the user. The application was tested on the dataset of a disease diagnosis of a paddy crop. The chi-square (χ2) test was used to match the result of the mAgIDS system with the experts’ inferences. It was found that the results of the system and experts match with an accuracy of 95.84% at a 5% level of significance. Twenty-two scientists, working at various locations within Punjab state in India, were contacted for validation of the system, with 15 relevant parameters. It was found that the proposed system is statistically valid. The real-time implementation of the system provides immense and timely help to the farmers in making appropriate decisions for their crop production.  相似文献   
88.
The effects of feeding Wistar rats with blended and interesterified oils of coconut (CO):groundnut (GNO) or CO:olive (OLO) on liver antioxidant enzyme activities and susceptibility of LDL to oxidation were studied. The hepatic lipid peroxidation (LPO) levels in the rats fed CO:GNO blend and interesterified oils were increased by 31% and 21%, when compared to the rats given CO. The superoxide dismutase activity was increased by 31% and 28%, and catalase (CAT) activity was increased by 37% and 39%, respectively, in rats given blends and interesterified oils of CO:GNO, as compared to those given CO. The activities of glutathione peroxidase (GPx) were increased by 17% and 20% in rats given CO:GNO blend and interesterified oils. Glutathione transferase (GST) level was also found to be increased by 26% and 31% after feeding blended and interesterified oils of CO:GNO, compared to those given CO. The LDL oxidation, which was elevated by feeding GNO, was found to be reduced by 10% and 14%, respectively, in the groups fed blended and interesterified oils of CO:GNO. Similarly, CO:OLO blended oils enhanced SOD, CAT, GPx and GST activities by 34%, 43%, 27% and 23%, respectively, compared to the rats given CO-containing diets. The corresponding increases in theses antioxidant enzyme activities when CO:OLO interesterified oils were fed to rats were 38%, 50%, 28% and 26%, respectively, when compared to rats given CO-containing diets. There was a significant reduction in hepatic LPO as well as oxidation of LDL, when blended and interesterified oils of CO:OLO were fed to rats. The results demonstrated that blended and interesterified oils of CO with GNO or OLO enhance hepatic antioxidant enzymes, decreased lipid peroxidation in liver and reduced the susceptibility of LDL to oxidation.  相似文献   
89.
Conjugated linoleic acid (CLA) that is commonly found in dairy and ruminant fats, is geometrical and positional isomer of linoleic acid (LA). Edible oils are not good sources of CLA. Attempts have been made to generate CLA in edible oils through photoisomerization procedures. CLA isomers have several proven health benefits. This article reviews procedures for producing CLA containing edible oils by photoisomerization approach and applications of photoisomerized oils for food uses. The article reviews (1) the photoisomerized production of CLA containing oils on lab scale, with customized equipment, at pilot plant scale; (2) the effects of iodine content, photoisomerization time, refining, interference from minor components of oils, efficacy of different edible oils containing LA, interference from antioxidants; (3) the chemical kinetics, oxidative stability; and (4) photoisomerized oils for frying oils and as drying oils.The review also briefly covers methods of measurement of CLA.  相似文献   
90.
Glycosylated variants of ß-lactoglobulin (BLG) wereproduced in the methylotrophic yeast Pichia pastoris to mimicthe glycosylation pattern of glycodelin, a homologue of BLGfound in humans. Glycodelin has three sites for glycosylation,corresponding to amino acids 63–65 (S1), 85–87 (S2)and 28–30 (S3) of BLG. These three sites were engineeredinto BLG to produce the variants S2, S12 and S123, which carriedone, two and three glycosylation sites, respectively. The oligosaccharideson these BLG variants ranged from (mannose)9(N-acetylglucosamine)2(Man9GN2) to Man15GN2 and were of the  相似文献   
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