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741.
Previously successfully applied polyalkenyl-poly(maleic-anhydride)-ester/amide type additives synthesized in laboratory scale have gone through selection steps then the selected coupling additives were produced in industrial scale process. Additives have been applied for treating the surfaces of glass fibres with and then mechanical properties of the laminated polyester and vinyl–ester based composites have been determined. Results have been focussed on the effect of the size increasing of additive production on the final properties of the laminates. The structures of the additives have been compared based on their FT-IR spectra. Improvement of mechanical properties of composites treated by coupling additives has been found manufactured in industrial scale either. Tensile properties could be improved by 3.2–51.3% with additives from industrial scale related to the same properties of untreated laminates. The Charpy impact strength of laminates treated with coupling agents from industrial scale was higher than that of from lab scale. Fibre–matrix interaction has been studied on SEM micrographs of the fractured faces of the composites. Similarly, the unfavourable results had been caused by the fibres slipping out of the ester matrix.  相似文献   
742.
The mycotoxin ochratoxin A (OTA) is known to be heterogeneously distributed both intrinsically (from one individual food item to the next) as well as distributionally (throughout a sample of individual food items) in cereals and cereal-based foods. Therefore, proper sampling and sample comminution are special challenges, but are prerequisites for obtaining sound analytical data. This paper outlines the issue of the sampling process for cereals and cereal-based foods, starting with the planning phase, followed by the sampling step itself and the formation of analytical samples. The sampling of whole grain and retail-level cereal-based foods will be discussed. Furthermore, possibilities to reduce sampling variance are presented.  相似文献   
743.
Ion-selective microelectrodes can be employed as tips in scanning electrochemical microscopy (SECM) for chemical imaging of corrosion processes. They present higher chemical selectivity than conventional amperometric microdisks, and may be the only effective option to visualize the dissolution of metals with negative redox potentials in aqueous environments when the use of Pt microelectrodes is limited by the onset of oxygen reduction and hydrogen evolution reactions. A robust micro-sized ion selective electrode has been developed which allows the spatial distribution of Zn2+ during galvanic corrosion of a model Fe/Zn couple to be investigated using SECM. Owing to the low internal contact potential achieved with the novel design, the resistance of the micropipette electrodes is only fractions of the resistance of conventional micropipette electrodes of the same size. As a result, no special shielding of the microelectrodes is required and higher scanning rate can be used for scanning in the potentiometric modes using these micropipette tips. Concentration profiles over corroding surfaces measured with this technique will be presented.  相似文献   
744.
杨莉莉 《门窗》2007,(1):51-54
木窗,包括纯木窗,铝包木窗和木铝复合窗,作为一种相对新兴的窗型,近些年在国内发展迅速.而作为一种成熟产品,木窗在欧洲已经存在完整的生产和安装标准.我们可以借鉴国外的成熟技术加速自身完善.  相似文献   
745.
A pathological increase of the permeability of the mitochondrial membranes may culminate in the irreversible rupture of the mitochondrial outer membrane. Such a permeability transition is lethal because it results in the release of death-inducing molecules from mitochondria and/or metabolic failure. Current methods to assess this outer membrane damage are mostly indirect or scarcely representative of the overall mitochondrial population. Here we present an analytical and preparative approach using free flow electrophoresis to directly distinguish rat liver mitochondria that have undergone the permeability transition from unaffected organelles or from organelles that are damaged to a minor degree. Mitochondrial populations, which considerably differ in outer membrane integrity or cytochrome c content, were separated by this means. We further show that the relative abundance of each population depends on the dose of the permeability transition inducer and the duration of the treatment time. Finally, we have employed this approach to investigate the impairment of mitochondria that were isolated from livers subjected to ischemia/reperfusion damage.  相似文献   
746.
747.
The objective was to study the effect of feeding diets varying in rumen undegradable protein on DMI, growth, feed efficiency, and carcass composition in Holstein calves from birth to 25 wk of age. Sixty Holstein calves were assigned in a randomized complete block design to one of three dietary treatment groups that differed in rumen undegradable protein as a percentage of total protein. Protein undegradabilities of the TMR fed for ad libitum intake for period 1 (wk 1 to 12 of age) were 33, 37, and 46% and for period 2 (wk 14 to 25 of age) were 30, 34, and 38%. Intake was not different among diets during period 1. During period 2, animals fed the highest and lowest levels of undegradable protein diet consumed less DM, and those animals on the highest undegradable diet had the least amount of crude protein intake. Feed efficiency was increased with increasing rumen undegradable protein for period 2. Carcass composition was not affected by dietary treatment for either 9-10-11 rib section or the half carcass. Prediction equations for carcass protein and fat were calculated for 25-wk Holstein calves using urea space and live weight. These results indicate that the amount of undegradable intake protein currently recommended for growing dairy replacements may not be justified when intake is ad libitum. In the present study, urea space was not found to be beneficial over live weight for predicting carcass protein and fat in intact male or female Holstein calves.  相似文献   
748.
The objective of this study was to monitor the viability during storage of Lactobacillus acidophilus LA-5 (A), Bifidobacterium animalis ssp. lactis BB-12 (B), and Streptococcus thermophilus CHCC 742/2130 (T) in probiotic cultured dairy foods made from pasteurized camel, cow, goat, and sheep milks fermented by an ABT-type culture. The products manufactured were stored at 4°C for 42 d. Microbiological analyses were performed at weekly intervals. Streptococcus thermophilus CHCC 742/2130 was the most numerous culture component in all 4 products both at the beginning and at the end of storage. The viable counts of streptococci showed no significant decline in fermented camel milk throughout the entire storage period. The initial numbers of Lb. acidophilus LA-5 were over 2 orders of magnitude lower than those of Strep. thermophilus CHCC 742/2130. With the progress of time, a slow and constant decrease was observed in lactobacilli counts; however, the final viability percentages of this organism did not differ significantly in the probiotic fermented milks tested. The cultured dairy foods made from cow, sheep, and goat milks had comparable B. animalis ssp. lactis BB-12 counts on d 0, exceeding by approximately 0.5 log10 cycle those in the camel milk-based product. No significant losses occurred in viability of bifidobacteria in fermented camel, cow, and sheep milks during 6 wk of refrigerated storage. In conclusion, all 4 varieties of milk proved to be suitable raw materials for the manufacture of ABT-type fermented dairy products that were microbiologically safe and beneficial for human consumption. It was suggested that milk from small ruminants be increasingly used to produce probiotic fermented dairy foods. The development of camel milk-based probiotic cultured milks appears to be even more promising because new markets could thus be conquered. It must be emphasized, however, that further microbiological and sensory studies, technology development activities, and market research are needed before such food products can be successfully commercialized.  相似文献   
749.
In this paper we argue that it is necessary to apply economic impact models in smart specialization policy in order to come up with reliable economic impact estimations. Solutions suggested in the smart specialization (S3) literature for economic impact assessments cover the economic effects only partially. To estimate the impacts in the industrial, regional and national dimensions in their entirety the application of specifically designed economic models becomes necessary. We extended the geographic macro and regional (GMR)-Hungary policy impact model with additional features to make this model applicable for S3 economic impact estimations. In our policy simulations we illustrate how the application of this model helps policy-makers in the prioritization process.  相似文献   
750.
The impact of minimal heat-processing of juices on the activities of endogenous pectin methylesterase (PE) and peroxidase (POD) was compared between Citrus species. Mono-cultivar juices were produced from three orange (Citrus sinensis (L.) Osbeck cvs. ‘Navelina’, ‘Salustiana’, and ‘Navelate’), two lemon (Citrus limon (L.) Burm. f. cvs. ‘Verna’ and ‘Primofiori’), and two Clementine mandarin varieties (Citrus reticulata Blanco cvs. ‘Marisol’ and ‘Clemenules’). Two mandarin hybrids (cvs. ‘Ortanique’ and ‘Clemenvilla’) were likewise used. The freshly squeezed juices were subjected to continuous treatments at six different temperatures (42–92 °C) with subsequent re-cooling on the pilot plant scale. In fresh Citrus juice, POD activities notably varied between 0.2 and 7.5 nkat g−1 of juice, whereas PE activities were more uniform (0.4–1.5 PE units g−1). In all juices, except ‘Ortanique’ juice, heating ≥42 °C for 12 s reduced POD activity below 4.3% of the maximum activity in fresh Citrus juice. Thermal tolerance of the thermo-labile PE fraction was overall much higher, but varied among juices during heating at temperatures ≤62 °C. Overall thermal resistance of PE was though comparable, with deactivation exceeding 84%, mostly even 90%, after thermal treatments ≥72 °C. Unlike POD, total PE activity proved to be an indicator of freshness that is universally applicable to Citrus juices derived from orange, mandarin, and lemon or blends thereof. Freshly squeezed juices can analytically be distinguished from cold-stored, minimally processed products that display an almost completely inactivated thermo-labile PE fraction and thus extended shelf life.  相似文献   
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