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51.
The quantitative and qualitative distribution of carotenoids in different body components of four species of shrimp (Penaeus monodon, Penaeus indicus, Metapenaeus dobsonii and Parapenaeopsis stylifera) harvested from shallow waters off the Indian coast was assessed. The highest total carotenoid contents were observed in the head (153.1 µg g?1) and carapace (104.7 µg g?1) of P stylifera, while the body components of P indicus showed the lowest carotenoid levels. Astaxanthin and its mono‐ and diesters were the major carotenoids (63.5–92.2% of total carotenoids) present in the carotenoid extracts from the shrimps, while the extracts contained low levels of β‐carotene and zeaxanthin. The major fatty acids in the carotenoid extracts were palmitic, heptadecanoic, palmitoleic, stearic and oleic acids. Copyright © 2004 Society of Chemical Industry  相似文献   
52.
Methods are presented for mathematically determining dispersal of a vapor in still air, in turbulent air of zero average velocity, and in turbulent or laminar air currents of constant, nonzero average velocity. The methods are combined with several assumptions about insect behavior to derive an insect attraction model that predicts: (1) In a warehouse a searching insect is likely to be attracted to a calling insect if it comes within an attraction sphere, 0.4–2.5 m in radius. (2) The attraction spaces of typical sex pheromone-baited traps that emit pheromone at rates greater than 0.01 ng/sec extend beyond the boundaries of a 10 × 10 × 10-m warehouse. (3) The searching behavior of an attracted insect is likely to be altered from an extensive to an intensive pattern if it comes within an altered-behavior sphere, 6–60 cm from a calling insect or within 10 m of a trap emitting 0.76 ng/sec. (4) Pheromone does not sink unless it is emitted along with a large amount of a high-vapor pressure solvent. The model is used in support of several hypotheses, including: (1) The effect of an adsorptive surface on the vapor concentration after an extended period of emission is negligible except at positions near the surface. (2) Sex pheromone-baited traps with sources of small dimensions have greater trapping efficiency than otherwise identical traps with sources of large dimensions.  相似文献   
53.
Moisture sorption data are useful in choosing suitable packaging material having a desirable water vapour barrier property in addition to determining the stability of the product. The sorption isotherms of milk burfi, one of the important Indian traditional milk-based sweets, using sugar and sugar substitutes were determined. The product was prepared replacing sugar with sorbitol, maltodextrin (MD)+polydextrose (PD), and PD alone, along with aspartame to give an equi-sweetness level compared to sugar. The isotherms followed typical sigmoidal shape, characteristic of sugar-rich products. The curve for burfi with sorbitol shifted to the left compared to that of sugar, whereas for those prepared with MD+PD or PD, the curves are similar to that of burfi made with sugar. Several models were chosen to fit sorption behaviour and the Guggenheim-Anderson-De Boer model showed a better fit compared to other models.  相似文献   
54.
Evolutionary trends in the technologies related to Indian Space Research Organisation (ISRO) satellites, both past and present, are outlined. The issues related to the developmental complexities of different spacecraft subsystems are discussed in the context of the needs of the current generation operational spacecraft like the Indian Remote Sensing Satellite (IRS) and the Indian National Satellite (INSAT) II. Considerations pertinent to reliability and long-life requirements, crucial to operational satellites, are also highlighted.  相似文献   
55.
Fatty acid compositions of fish oil extracted from different parts of Indian mackerel (Rastrelliger kanagurta) using various techniques of supercritical carbon dioxide (SC-CO2) at optimised conditions (35 MPa, 60 °C, 2 ml/min) were analysed and compared to the results of Soxhlet extraction. The amount of polyunsaturated fatty acids (PUFA) recovered (as a percentage of total extracted fatty acids) were within the ranges of 73.24–74.68% in the skin, 68.36–69.37% in the flesh, 56.20–57.3% in the viscera and 61.21–62.09% in the heads. The greatest amount of the ω-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were found in fish skin followed by flesh, heads and viscera. The greatest amounts of EPA (9–12%) and DHA (10–14%) were obtained using the soaking and pressure swing techniques. The pressure swing and soaking techniques are the most effective techniques for extracting the ω-3 family of fatty acids from fish samples.  相似文献   
56.
The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH4-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg− 1 dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.  相似文献   
57.
近红外光谱法快速鉴别涪陵榨菜品牌的研究   总被引:1,自引:1,他引:0  
刘冰  杨季冬 《食品工业科技》2011,(8):397-399,403
提出了一种基于近红外漫反射光谱技术快速鉴别涪陵榨菜品牌的方法。应用近红外漫反射光谱技术对市场上6种典型品牌涪陵榨菜提取光谱,并对获得的原始光谱数据进行平滑、一阶导数以及矢量归一化等预处理后,采用因子法计算样品间的光谱距离,通过ward’salgorithm方法进行聚类分析。并与判别分析的实验结果进行了对比,结果显示聚类分析和判别分析对6种涪陵榨菜品牌均能很好地鉴别。  相似文献   
58.
Overlapping community detection has become a very hot research topic in recent decades, and a plethora of methods have been proposed. But, a common challenge in many existing overlapping community detection approaches is that the number of communities K must be predefinedmanually. We propose a flexible nonparametric Bayesian generative model for count-value networks, which can allow K to increase as more and more data are encountered instead of to be fixed in advance. The Indian buffet process was used to model the community assignment matrix Z, and an uncollapsed Gibbs sampler has been derived.However, as the community assignment matrix Z is a structured multi-variable parameter, how to summarize the posterior inference results and estimate the inference quality about Z, is still a considerable challenge in the literature. In this paper, a graph convolutional neural network based graph classifier was utilized to help to summarize the results and to estimate the inference quality about Z. We conduct extensive experiments on synthetic data and real data, and find that empirically, the traditional posterior summarization strategy is reliable.  相似文献   
59.
Scientists and engineers’ social background, cultural upbringing, educational training, and world outlook influence how they perform the work and interact with their colleagues. We conducted a study on Indian immigrant scientists and engineers employed in the US industrial sector. We interviewed 40 Indian immigrant scientists and engineers, some of whom came for higher studies and found employment after graduation, while others came directly from India to work. Findings show that the overwhelming majority of interviewees (n = 35) noted significant cultural differences with their colleagues in the workplace; only a small number of interviewees (n = 5), believed that their foundation in professionalism eliminated significant impacts from cultural dissimilarities. Interviewees identified cultural differences in the areas of social interactions, work-related practices, intercultural communication, and management. When immigrant scientists and engineers from developing countries join industrial organizations, they do not leave their cultural practices at home. A conversation with Indian immigrant scientists and engineers shows how Indian culture manifests itself in the workplace.  相似文献   
60.
A membrane-based process to produce protein isolates from seeds of oriental mustard (Brassica juncea) was developed by modifying a method originally developed for rapeseed. The optimized process consisted of extraction at pH 11, ultrafiltration with concentration factor 4, diafiltration with diavolume 3, and precipitation at pH 5. The process, based on defatted oriental mustard seed containing 45–50% protein, recovered 81% of the protein in useful products: 47.3% in precipitated protein isolate (PPI), 3.8% in soluble protein isolate (SPI), and 13% in meal residue. Mass yields were 21.9% in PPI, 2.8% in SPI, and 38.4% in meal residue. The losses in the system included ∼10% loss of nonprotein nitrogen, and <9% into permeate and transfer losses. The PPI compared favorably with soy protein isolate in typical meat products in terms of color, texture, and flavor. The work confirms that oriental mustard is a potentially useful source of edible protein.  相似文献   
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