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本书中有两个发现和十七个成果。其中有十二个成果是关于当代数学的,另外的五个是解决了五个公元前250-550年之间的历史难题。发现之一是:本书系统地研究了不可分量(实数的空集合)及其性质。发现之二是:本书发现了标准微积分学的新模型-欧弥伽连续统模型。为了说清楚关于当代数学的十二个成果,令R代表实数集合且r∈R是任意的,这十二个成果是:Ⅰ.本书证明了实数集合不能填满一条建立了固定标架的欧几里德直线;Ⅱ.对确定了标架的Euclid直线L进行了完整的微分分拆,即L={-∞的右单子∪r的左单子∪r∪r的右单子∪∞的左单子}=欧弥伽连续统ΩΠ,并对无穷小量的积分建立了三条公理;Ⅲ.令ω代表r的左单子和r的右单子的共同测度,在标准数学中证明了ω是R之外的正无穷小;Ⅳ.对若当,卡拉特欧多里和勒贝格测度论中的两条公理给出了宇观的、宏观的和微观的反例,并给出了欧弥伽极限协调性测度的新概念;Ⅴ.由单个自然数的测度为零证明了自然数集合N的测度也等于零;并且由单个实数的测度为零证明了实数集合R的测度等于零;Ⅵ.在ΩΠ中定义了序和算术运算;Ⅶ.把外尔斯特拉斯极限改进为欧弥伽极限;Ⅷ.把狄特金分割改进为欧弥伽分割;Ⅸ.把康托连续统改进为欧弥伽连续统;Ⅹ.在ΩΠ中给出了欧弥伽定积分的定义;Ⅺ.对于一个实数 相似文献
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Experimental evidence of concurrent compositional and structural instabilities leading to ω precipitation in titanium-molybdenum alloys 总被引:1,自引:0,他引:1
A. DevarajS. Nag R. SrinivasanR.E.A. Williams S. BanerjeeR. Banerjee H.L. Fraser 《Acta Materialia》2012,60(2):596-609
The ω phase is commonly observed in many commercial β or near-β titanium alloys on rapidly cooling from the single β phase field and also during subsequent isothermal annealing. However, the crystallographic formation mechanism for the ω particles is hitherto unclear/under discussion. The present study primarily focuses on ω precipitation within the β (body-centered cubic (bcc)) matrix of simple model binary titanium-molybdenum (Ti-Mo) alloys. It provides direct experimental evidence of the formation of ω-like embryos from competing compositional and structural instabilities arising in the bcc lattice of Ti-Mo alloys during rapid cooling from the high-temperature single β phase field. The displacive partial collapse of the {1 1 1} planes of the parent bcc structure within compositionally phase-separated regions containing several at.% less of Mo, forming ω-like embryos, has been conclusively shown by coupling aberration-corrected high-resolution scanning transmission electron microscopy with atom probe tomography observations. Growth and coarsening of these ω-like embryos take place during subsequent isothermal annealing, accompanied with both a completion of the collapse of the {1 1 1} β planes leading to a fully developed ω structure as well as rejection of Mo from these precipitates, resulting in near-equilibrium compositions. 相似文献
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Incorporation of Alpha‐Linolenic Acid and Enhancement of n‐3 Fatty Acids in Nile Tilapia: a Factorial Design
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![点击此处可从《Journal of the American Oil Chemists](/ch/ext_images/free.gif)
Vanessa Vivian Almeida Schneider Fabiana Carbonera Paula Fernandes Montanher Ana Paula Lopes Makoto Matsushita Jesuí Vergílio Visentainer 《Journal of the American Oil Chemists' Society》2015,92(5):693-700
A 22 factorial design (two factors at two levels, in triplicate) was performed to investigate the influence of factors A (time of treatment, 15 and 30 days) and B (chia oil content in a supplemented diet, at 2.1 and 4.2 %) in three responses of interest referring to: (a) the incorporation of alpha‐linolenic acid (LNA) in lipids of Nile tilapia fillet; (b) the enhancement of n‐3 fatty acids; and (c) the decrease in the omega‐6/omega3 (n‐6/n‐3) ratio in fish. Factors A and B were significant in the three regression models obtained and the interaction AB was a significant contributor to the LNA and n‐6/n‐3 ratio. Analysis of variance suggested three significant and predictive mathematical models. Response surfaces analyses from designs indicated higher LNA and n‐3 contents and a lower n‐6/n‐3 ratio using both factors A and B in the higher levels (30 days of treatment and 4.2 % of chia oil in the diet for fish) chosen for this study. 相似文献
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Effect of addition of Agaricus blazei mushroom residue to milk enriched with Omega‐3 on the prevention of lipid oxidation and bioavailability of bioactive compounds after in vitro gastrointestinal digestion
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![点击此处可从《International Journal of Food Science & Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ana Carolina P. Vital Camila Croge Sandra Maria Gomes‐da‐Costa Paula T. Matumoto‐Pintro 《International Journal of Food Science & Technology》2017,52(6):1483-1490
The residue from a hydroalcoholic extract of the mushroom Agaricus blazei (MAR) was evaluated for phenolic compounds, flavonoids and antioxidant activity. The ability of MAR to slow the oxidation of Omega‐3 resulting from light exposure in milk matrix, and its bioavailability after in vitro digestion was investigated. MAR presented phenolic compounds and flavonoids and showed antioxidant activity. At each concentration, addition of MAR to Omega‐3‐supplemented milk inhibited the production of conjugated dienes and malonaldehyde compared with samples without MAR. The bioavailability assay showed that polyphenols were still present after in vitro digestion and had antioxidant activity. 相似文献
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The consumption of omega‐3 polyunsaturated fatty acids (n‐3 PUFA) is associated with a reduced risk of breast cancer. Studies in animals and in vitro have demonstrated mechanisms that could explain this apparent effect, but clinical and epidemiological studies have returned conflicting results on the practical benefits of dietary n‐3 PUFA for prevention of breast cancer. Effects are often only significant within a population when comparing the highest n‐3 PUFA consumption group to the lowest n‐3 group or highest n‐6 group. The beneficial effects of n‐3 PUFA eicosapentaenoic and docosahexaenoic on the risk of breast cancer are dose dependent and are negatively affected by total n‐6 consumption. The majority of the world population, including the most highly developed regions, consumes insufficient n‐3 PUFA to significantly reduce breast cancer risk. This review discusses the physiological and dietary context in which reduction of breast cancer risk may occur, some proposed mechanisms of action and meaningful recommendations for consumption of n‐3 PUFA in the diet of developed regions. 相似文献
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