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991.
选用服装厂常用的6种雪纺织物,测定其基本参数,采用正交试验方法,分析线迹密度、机针、缝纫线3种缝纫参数对缝口强度的影响及雪纺织物性能与缝口强度的相关性。试验结果表明:对于较薄的雪纺织物,缝口破坏形式为纱线滑脱,线迹密度的影响最为显著,缝口强度与线迹密度成负相关;对于较厚的雪纺织物,缝口破坏形式为缝纫线断裂,缝纫线的影响最为显著,缝口强度与线迹密度、缝纫线粗细成正相关;而机针对缝口强度的影响最小。 相似文献
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993.
通过PCR检测食用油中内源性DNA是鉴定食用植物油品种真实属性,检测食用油掺假的一种有效方法。然而由于精炼的食用油中DNA含量极低,如何有效富集食用油中的DNA是实现PCR鉴别粮油的关键。因此,作者研究了磁珠法富集食用油中的DNA并通过实时荧光PCR检测芝麻油、菜籽油、稻米油的内源基因。结果表明经过5次乳化后和磁珠进一步富集水相中的DNA,实时荧光PCR成功检测到了食用油中的内源性基因,琼脂糖凝胶电泳分析进一步证明实现了上述3种食用植物油的定性鉴定。 相似文献
994.
Meizhu Wang Yu Cao Maoning Xia Abdullah M.S. Al-Hatmi Weizheng Ou Yanyan Wang Andriy A. Sibirny Liang Zhao Chenggang Zou Wanqing Liao Fengyan Bai Xie Zhi Sybren de Hoog Yingqian Kang 《Yeast (Chichester, England)》2019,36(5):363-373
A set of 185 strains of Candida albicans from patients with vulvovaginal candidiasis (VVC) and from non-VVC clinical sources in southwest China was analysed. Strains were subjected to genotyping using CAI microsatellite typing and amplification of an intron-containing region of the 25S rRNA gene. Microsatellite genotypes of strains from non-VVC sources showed high polymorphism, whereas those of VVC were dominated by few, closely similar genotypes. However, among non-VVC strains, two genotypes were particularly prevalent in patients with lung cancer. 25S rDNA genotype A was dominant in VVC sources (86.7%), whereas genotypes A, B, and C were rather evenly distributed among non-VVC sources; known genotypes D and E were not found. In an experimental mouse model, isolates from lung cancer and AIDS patients proved to have higher virulence than VVC strains. Among 156 mice infected with C. albicans, 19 developed non-invasive urothelial carcinoma. No correlation could be established between parameters of virulence, source of infection, and incidence of carcinoma. C. albicans strains from VVC were less susceptible to itraconazole than the strains from non-VVC sources, whereas there was small difference in antifungal susceptibility between different 25S rDNA genotypes of C. albicans tested against amphotericin B, itraconazole, fluconazole, and flucytosine. 相似文献
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996.
Yueyu Zou Kehan Pei Xichun Peng Weibin Bai Caihuan Huang Shiyi Ou 《International Journal of Food Science & Technology》2016,51(4):1002-1009
This work aimed to investigate the reactivity of hydroxymethylfurfural (HMF) with selected amino acids, to identify the produced adducts and to clarify whether or not the adducts release HMF after their digestion under gastric conditions. Results showed that cysteine, glycine and lysine can deplete the added HMF, and their reactivity increased with increasing pH and temperature. Cysteine (25 μmol mL?1) depleted 91.0% of the added HMF (315.3 μg mL?1) at 40 °C in 15 min, lysine did not eliminate HMF until 80 °C, and glycine started to eliminate HMF at 100 °C. Four adducts for cysteine, three adducts for lysine and only one adduct for glycine were identified through HPLC–MS–MS after they reacted with HMF. The adducts formed from the reaction mixture of cysteine, lysine and glycine with HMF only released 1.7%, 2.6% and 10.5% of eliminated HMF, respectively, after their digestion in simulated gastric conditions. 相似文献
997.
Shumin Liu Shiyi Ou Huihua Huang 《International Journal of Food Science & Technology》2016,51(6):1537-1543
To investigate two‐sided functions of tea polyphenols (TP) in antinutrition and energy balance modulation, TP were extracted from Chinese green tea and used to complex porcine pancreas α‐amylase (PPA). Changes of PPA in activity and secondary conformations were analysed. Porcine pancreas α‐amylase was found sensitive to TP treatment. Tea polyphenols exhibited IC50 at 0.41 mg mL?1 against PPA and maximum inhibitory rate (98.17%) at 3.0 mg mL?1. Tea polyphenols inhibition was concluded as noncompetitive pattern based on its unchanged Km value (0.98 mg mL?1) for soluble starch substrate. Tea polyphenols inhibition arose from pH 1.5 to 10.14, covering gastric and intestinal environments inside body. Circular dichroism spectra analysis revealed regular changes of PPA in secondary conformations (increased proportions of α‐helix and β‐sheet) prior to its inactivation at low TP concentrations. Tea polyphenols‐inhibited PPA had distinct double‐negative peaks at 204 nm and 208 nm. Porcine pancreas α‐amylase was inactivated by TP in ways of complexation and modification of secondary conformations. 相似文献
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1000.
5-羟甲基糠醛(5-HMF)是食品热加工过程中易产生的内源性有害物,目前对其研究普遍集中于面包、饼干等西式食品,对传统中式点心的研究甚少。本文分析了市售蓝莓酥和凤梨酥产品,发现蓝莓含量高的酥馅料中5-HMF水平显著高于凤梨酥馅料和蓝莓配料含量低的样品。通过实验室制备蓝莓酥与凤梨酥,分析馅料中5-HMF的形成规律,发现5-HMF主要产生于酥馅炒制过程,焙烤对其影响较小;且5-HMF在蓝莓馅料中的产生量是凤梨馅料的4倍。成分分析发现:造成蓝莓酥馅料5-HMF含量高于凤梨酥的因素有:1)蓝莓酥馅料的低pH值环境有利于5-HMF生成;2)蓝莓馅料中以己糖为主,葡萄糖和果糖含量分别是凤梨馅料的2.2倍和3.3倍,且加工过程中蔗糖降解严重,而凤梨馅料以蔗糖为主,酸性条件下己糖脱水是形成5-HMF的主要途径;3)蓝莓馅料中氨基酸含量(主要为丝氨酸和谷氨酸)较凤梨馅料高,促进美拉德反应形成5-HMF。以上结果提示:蓝莓作为配料添加于果酥等热加工食品制作中,有促进内源性有害物如5-HMF形成的风险。本文为中式糕点中内源性有害物的形成与控制提供了数据参考。 相似文献