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21.
A Comparative Study on Changes and Relationships of Kernel Biochemical Components in Different Types of Maize 下载免费PDF全文
Fatih Kahrıman Cem Ömer Egesel Başak Egesel 《Journal of the American Oil Chemists' Society》2015,92(10):1451-1459
A great deal of genetic variability and breeding efforts have yielded a number of specialty maize types. Little is known about how the off‐target traits in specialty maize kernel have changed and how they compare to those of standard maize genotypes. In this study, we compared the normal (NORMAL), high‐oil (HOM) and high‐protein maize (HPM) genotypes in terms of oil, protein, fatty acids and some mineral components. We also investigated the relationships among the evaluated traits in different kernel types. We detected a significant variation among the maize types for all of the investigated traits. Specialty maize genotypes had a superior performance for the traits they were specifically bred for, as well as kernel mineral content over the normal genotypes. HOM and HPM had similar values in terms of their fatty acid composition. However, they were different from the standard genotypes, with higher oleic and lower linolenic acid levels, which indicates that the specialty maize genotypes possess a better oil quality. Correlation analysis revealed that only three pairs of correlations out of 46 values had the same sign and a similar level of significance in different types. Such similarities or differences in correlation values for different types should be taken into account in the efforts for developing high quality maize genotypes. 相似文献
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Zhi‐Gang Luo Xiong Fu Qun‐Yu Gao Shu‐Juan Yu 《International Journal of Food Science & Technology》2011,46(2):429-435
Maize starches with different amylose contents (0%, 23% and 55%) were treated in anhydrous methanol, ethanol, 2‐propanol, 1‐butanol with 0.36% HCl at 25 °C for 5 days. Results showed that the extent of change in physicochemical properties increased from methanol to butanol. Treated waxy maize starch showed higher than 65% solubility at above 75 °C. The diffraction peak at 2θ = 5.3° of amylomaize V starch disappeared after treatment in ethanol, 2‐propanol and 1‐butanol. Acid–alcohol treatment decreased the gelatinisation temperature of normal (from 64.5 to 61.9 °C) and waxy maize (from 68.1 to 61.1 °C) starches, while it increased that of amylomaize V (from 68.7 to 72.3 °C) starch. The extent of the decrease in the pasting viscosity followed the following order: amylomaize V < normal maize < waxy maize. This study indicated that acid–alcohol treatment degraded preferentially the amorphous regions and the different changes depended on the crystal structure and amylose content of starch. 相似文献
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Valentina V Semenčenko Ljiljana V Mojović Aleksandra P Đukić‐Vuković Milica M Radosavljević Dušanka R Terzić Marija S Milašinović Šeremešić 《Journal of the science of food and agriculture》2013,93(4):811-818
BACKGROUND: Bioethanol is mostly produced from starchy parts of the corn grain kernel leaving significant amounts of valuable by‐products such as dried distillers' grains with solubles (DDGS) which can be used as a substitute for traditional feedstuff. The suitability of six maize hybrids from Serbia was investigated for bioethanol and DDGS production. The correlation between physical and chemical characteristics of the grain, bioethanol yield and quality of the corresponding DDGS was assessed. RESULTS: All hybrids had very different chemical composition and physical characteristics which could allow various applications. The highest bioethanol yield (94.5% of theoretical) and volumetric productivity (2.01 g l?1 h?1) were obtained with hybrid ZP 434 and the lowest with ZP 611k. Regarding chemical composition, all DDGS samples manifested good properties as feed components. Their protein content was higher compared to the kernel. In addition, the samples showed high digestibility and high mineral content, especially of calcium and phosphorus. CONCLUSION: A hybrid ZP 434 was selected as the most promising bioethanol producer. This property is attributed to the highest level of soft endosperm which is more susceptible to starch‐hydrolysing enzymes. A high yield potential per hectare makes it the best candidate for commercial bioethanol production. © 2012 Society of Chemical Industry 相似文献
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M.E. Lyn R.M. Zablotowicz B.J. Johnson 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(3):381-387
While soil application of a competitive non-toxigenic Aspergillus flavus strains is successful in reducing aflatoxin contamination in certain crops, direct application to aerial reproductive structures could be more effective for maize. A sprayable, clay-based water-dispersible granule formulation was developed to deliver non-toxigenic A. flavus strain K49 directly to maize ears. The efficacy of the K49 water-dispersible granule in mitigating aflatoxin in maize (Zea mays L.) was evaluated. Field studies were conducted to compare K49 colonization and effectiveness in reducing aflatoxin contamination when applied either as a soil inoculant or as a directed spray in plots infested with toxigenic strain F3W4. Fifty percent of non-toxigenic A. flavus was recovered from non-treated controls and from plots soil inoculated with K49 on wheat. In spray treatments with formulated or unformulated K49 conidia, over 90% of A. flavus recovered was non-toxigenic. Soil-applied K49 reduced aflatoxin contamination by 65% and spray applications reduced contamination by 97%. These findings suggest direct spray application of non-toxigenic A. flavus strains may be better than soil inoculation at controlling maize aflatoxin contamination and that a water-dispersible granule is a viable delivery system for maintaining viability and efficacy of the biological control agent, K49. 相似文献
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Zhou Bo Liao Renkuan Li Yunkai Gu Tao Yang Peiling Feng Ji Xing Weimin Zou Zhichao 《应用聚合物科学杂志》2012,126(2):423-435
Adding inorganic materials in SAPs to synthesize organic–inorganic composite superabsorbent polymers (OICSAPs) can effectively improve salt‐tolerance, gel strength, thermal stability, and water retention. However, most researches mainly focus on synthesizing process optimization and new multifunctional products, lacking reports on how ions affected water‐absorption characteristics and mechanism of OICSAPs and its influence on summer maize root growth. On the basis of these, we set up laboratory experiments and field cultivation experiment, using environmental scanning electron microscopy (ESEM) and fractal theory to study the questions above. Results show that OICSAPs have better salt‐tolerance, while cations and concentration affected its water‐absorption characteristics significantly. With higher cation valence, larger ionic radius, and concentration, its water‐absorption rate reduced remarkably as Na+ < K+ < Mg2+ < Ca2+ < Fe2+ < Fe3+ < Al3+ < Cu2+, while the effects of anions could be neglected. The OICSAPs presented typical honeycomb membrane‐like 3D crosslinked network structure, but Ca2+, Mg2+, Fe2+, Fe3+, Al3+, and Cu2+ would damage the structure (Cu2+ with the most significant effect) in local microdomain, and changed the complexity of pores. In the experiment, higher concentration could reduce water‐absorption rate without changing micromorphological characteristics. Applying OICSAPs will reduce total length, surface area, and volume of summer maize root, while promoting absorbing and transmitting ability by larger root diameter and the proportion of root <0.5 cm. All these results will provide a theoretical basis on application, marketing, and product development of OICSAPs. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Catherine Grard Paul Colonna Alain Bulon Vronique Planchot 《Journal of the science of food and agriculture》2001,81(13):1281-1287
Starches from single and double maize mutants were subjected to enzymatic degradation by porcine pancreatic α‐amylase. The maize mutants covered a broad range of macromolecular composition and crystalline structure relative to fractional crystallinity level (from 0.19 to 0.48) and polymorphic type (with various proportions of A‐, B‐ and V‐type allomorphs). Regardless of amylose content or crystallinity level, starches with a predominant B‐crystalline type were more resistant to amylolysis than others, and initial rates of hydrolysis were lower for B‐type than A‐type starches. Final hydrolysis extents were less than 35% for predominant B‐type starches, 60% for C‐type ones and more than 70% for predominant A‐ or V‐type ones. Dangling chains or crystal defects also appeared to increase initial hydrolysis rates, although lower initial rates and final hydrolysis extents were mainly related to the amount of B‐type crystallites. Unexpectedly, hydrolysis residues were composed of both amorphous and B‐type crystalline regions. These observations suggest that resistance to amylolysis is related to the distribution of B‐type crystallites within the granule rather than to the relative proportion of B‐type crystallites. © 2001 Society of Chemical Industry 相似文献
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Jean‐Pierre Guyot 《International Journal of Food Science & Technology》2012,47(6):1109-1114
Cereal‐based fermented foods are major contributors to energy intake in developing countries (DC). Their microbiota is dominated by lactic acid bacteria and has been extensively investigated. Diversity studies have been facilitated by molecular methods enabling genotyping of isolates; the rapid development of ‘omics’ approaches should facilitate more comprehensive studies to describe the relation between microbial diversity, cell physiology and product characteristics. Also, the link between the food microbiota and health benefits, in particular in nutrition, should be investigated. There is a need to encourage researches in the field of DC cereal‐based foods in direction of more mechanistic approaches. 相似文献