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61.
为了探究典型长寿区大米有机硒的赋存形态与人体硒营养水平的关系,本文分析了江西典型长寿区大米中有机硒、谷蛋白硒、硒代蛋氨酸(Selenomethionine, SeMet)等的组成特征,并运用胃肠体外模拟法对大米硒的生物可利用度及其与各有机硒组分之间的相关关系进行了研究。结果表明,大米中的硒主要以有机形式(78.67 ± 13.52%)赋存,其中,53.73 ± 8.27%的有机硒为谷蛋白硒,且65%以上的谷蛋白硒可酶解消化为SeMet。大米硒的生物可利用度为55.58 ± 10.53%。大米谷蛋白中SeMet比例相对较高且易于被人体吸收利用,这可能与当地居民的健康长寿关系密切。不过,SeMet与大米可利用硒的相关系数仅为0.55。因此,未来有必要对大米中不同硒蛋白的代谢产物(如SeMet)进行研究。 相似文献
62.
63.
食品硒源的生物学研究进展 总被引:35,自引:1,他引:34
硒是人体必需的微量元素,对人类健康有重要意义,机体硒的来源主要是食品,本文概述了食品硒源的地域性,硒含量及硒形态差异,并对硒的代谢、生物利用度、组织细胞分布、膳食硒的适宜范围,硒的营养状态评价和富硒功能性食等生物学研究进展进行了综述。 相似文献
64.
介绍了一种含硒丰富的啤酒——12Bx富硒红啤酒的研制方法,主要是利用富硒红曲米和麦芽,通过糖化、发酵等手段而制成。 相似文献
65.
本文利用原子吸收仪氢化物检测器与原子荧光检测不同类别的几种食品中的硒含量,通过对检测方法的对比试验,结果表明:通过试验两台仪器的加标收率都在标准允许的范围之内,说明我所两台仪器是稳定可靠的。通过比对试验说明,我所多年来使用的氢化物原子吸收方法检测食品中硒含量的检测方法数据是稳定可靠的,数据再现性较强。通过数据比较可以看出我所氢化物原子吸收检测食品中硒含量,数据的稳定性优于我所刚刚购置的原子荧光光度计。 相似文献
66.
Márcia G. Ventura Vekoslava Stibilj Maria do Carmo Freitas Adriano M.G. Pacheco 《Food chemistry》2009
The selenium content in fruit and vegetable samples from two regions in Portugal were analysed using hydride generation atomic fluorescence spectrometry (HG-AFS) and radiochemical nuclear activation analysis (RNAA) – two analytical methods with very low limits of detection. The lower detection limits of HG-AFS, 3 μg kg−1 and 8 μg kg−1 (according to conditions used for digestion), and for RNAA, 10 μg kg−1, meant that it was possible to determine selenium in samples previously analysed using the replicate sample instrumental nuclear activation analysis (RSINAA) with a higher detection limit associated. 相似文献
67.
Emese Kápolna Peter R. Hillestrøm Kristian H. Laursen Søren Husted Erik H. Larsen 《Food chemistry》2009
Carrot (Daucus carota) shoots were enriched by selenium using foliar application. Solutions of sodium selenite or sodium selenate at 10 and 100 μg Se ml−1, were sprayed on the carrot leaves and the selenium content and uptake rate of selenium were estimated by ICP–MS analysis. Anion and cation exchange HPLC were tailored to and applied for the separation of selenium species in proteolytic extracts of the biological tissues using detection by ICP–MS or ESI–MS/MS. Foliar application of solutions of selenite or selenate at 100 μg Se ml−1 resulted in a selenium concentration of up to 2 μg Se g−1 (dry mass) in the carrot root whereas the selenium concentration in the controls was below the limit of detection at 0.045 μg Se g−1 (dry mass). Selenate-enriched carrot leaves accumulated as much as 80 μg Se g−1 (dry mass), while the selenite-enriched leaves contained approximately 50 μg Se g−1 (dry mass). The speciation analyses showed that inorganic selenium was present in both roots and leaves. The predominant metabolised organic forms of selenium in the roots were selenomethionine and γ-glutamyl-selenomethyl-selenocysteine, regardless of which of the inorganic species were used for foliar application. Only selenomethionine was detected in the carrot leaves. The identity of selenomethionine contained in carrot roots and leaves was successfully confirmed by HPLC–ESI–MS/MS. 相似文献
68.
Takashi Kitaguchi Yasumitsu Ogra Yuji Iwashita Kazuo T. Suzuki 《European Food Research and Technology》2008,227(5):1455-1460
Buckwheat (Fagopyrum esculentum Moench) and quinoa (Chenopodium quinoa Willdenow) are widely used as food ingredients. The nutritional characteristics of these plants, i.e., high contents of proteins
and amino acids suggest that selenium (Se) is preserved as selenoamino acid derivatives, in particular, selenomethionine (SeMet)
in proteins, similar to selenized yeast. Therefore, buckwheat and quinoa are expected to be a good nutritional source of Se.
Selenized buckwheat and quinoa were cultivated on Se-fortified soil using sparingly soluble Se salts, such as barium selenate
and barium selenite. Se concentration in the edible parts of these plants was determined, and Se extraction efficiency with
enzyme or alkali was evaluated. In addition, the chemical species of Se in the low molecular weight fraction of these plants
were determined by HPLC-ICP-MS. Total Se concentrations in the edible parts of selenized buckwheat and quinoa were 170.4 ± 2.9 μg/g
and 102.7 ± 2.4 μg/g wet weight, respectively. Thus, these selenized seeds were found to be Se accumulators. The results indicate
that Se in selenized buckwheat exists mainly as SeMet, while Se in selenized quinoa exists not only as SeMet but also as selenate
(Se(VI)) and non-protein forms. 相似文献
69.
70.
敏捷开发模式的盛行掀起了自动化测试的一轮热潮,测试和开发合作越来越密切。本文研究的自动化测试框
架,将BDD 的敏捷开发理念与软件测试相融合,通过统一的Gherkin 语言定义验收测试标准,帮助业务人员、测试人员和开发
人员形成对需求明确统一的认识,然后通过web driver 测试代码实现可执行的验收测试,以TDD 的方式实现产品代码。该框
架使用Specflow、Selenium 和MsTest 等测试工具,真正实现了自动化测试,大大减少了手工测试的压力,促进开发测试过程中
软件开发涉众之间的沟通,及时得到用户反馈,满足快速发布产品的需求,提升产品质量。 相似文献