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81.
82.
红外图像技术在野生动物毛发识别中的应用 总被引:1,自引:0,他引:1
提出了红外图像在动物毛发识别中的应用和动物保护,尤其是国家濒危野生动物保护的重要意义,同时比较了目前动物毛发鉴定中使用的三种技术,分析了三种技术的利弊,建议组建野生动物毛发标准红外光谱图像数据库。 相似文献
83.
In the leek moth, Acrolepiopsis assectella, the male, stimulated by a calling female, produces a sexual pheromone that is active on the female. The male-produced pheromone blend contains eight alkanes previously isolated from the male hair-pencils. We used EAG techniques to study the effect of the pheromone on females reared on leek or on artificial diet and on males reared on leek. The optimal stimulation duration appeared to be 1.6 sec exposure to the pheromone or components. The concentrations tested on the antenna were of the order of 1012 molecules/cm3. The hair-pencil extract tested was of an estimated concentration of around 109 molecules/cm3. The antennal responses are expressed relative to responses to a standard, amyl acetate, but also as an absolute value. Generally, females reared on artificial diet and males reared on leek responded better than females reared on leek. Of the alkanes tested, those present in hair-pencils gave higher responses, with hexadecane always giving the strongest response. A possible inhibiting activity of male leek moth pheromone on the sexual behavior of conspecific males was investigated. The behavior of sexually stimulated males was observed in the presence of other males, hair-pencil extracts, and different compounds either pure or in a mixture. The experiments established that in this species, male pheromone inhibits wing fluttering duration of conspecific males. This inhibition was obtained not only with fluttering males as a source of pheromone but also with all the alkanes tested. The inhibition was due to hair-pencil chemicals, particularly if these were perceived by olfaction plus contact. Wing fluttering increased the inhibitory activity of male-derived alkanes. 相似文献
84.
对兔毛纤维的基本性能进行测试、分析研究,选择适当的混纺比和纺纱工艺路线,将兔毛与腈纶、锦纶、芦荟纤维进行混纺,在电脑横机上分别采用3种不同混纺比的兔毛混纺纱编织纬平组织,最后对织物的外观、基本物理性能及服用性能进行对比研究。 相似文献
85.
Huishan Zhang Shoubing Zhang Huashan Zhao Jingqiao Qiao Shuang Liu Zhili Deng Xiaohua Lei Lina Ning Yujing Cao Yong Zhao Enkui Duan 《International journal of molecular sciences》2015,16(8):17779-17797
Hair follicle stem cells (HFSCs) possess fascinating self-renewal capacity and multipotency, which play important roles in mammalian hair growth and skin wound repair. Although HFSCs from other mammalian species have been obtained, the characteristics of ovine HFSCs, as well as the methods to isolate them have not been well addressed. Here, we report an efficient strategy to obtain multipotent ovine HFSCs. Through microdissection and organ culture, we obtained keratinocytes that grew from the bulge area of vibrissa hair follicles, and even abundant keratinocytes were harvested from a single hair follicle. These bulge-derived keratinocytes are highly positive for Krt15, Krt14, Tp63, Krt19 and Itga6; in addition to their strong proliferation abilities in vitro, these keratinocytes formed new epidermis, hair follicles and sebaceous glands in skin reconstitution experiments, showing that these are HFSCs from the bulge outer root sheath. Taken together, we developed an efficient in vitro system to enrich ovine HFSCs, providing enough HFSCs for the investigations about the ovine hair cycle, aiming to promote wool production in the future. 相似文献
86.
Ultra‐structural hair alterations in Friedreich's ataxia: A scanning electron microscopic investigation
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F. Pinar Turkmenoglu U. Baran Kasirga H. Hamdi Celik 《Microscopy research and technique》2015,78(8):731-736
Friedreich's ataxia (FRDA) is an autosomal recessive inherited disorder involving progressive damage to the central and peripheral nervous systems and cardiomyopathy. FRDA is caused by the silencing of the FXN gene and reduced levels of the encoded protein, frataxin. Frataxin is a mitochondrial protein that functions primarily in iron‐sulfur cluster synthesis. Skin disorders including hair abnormalities have previously been reported in patients with mitochondrial disorders. However, to our knowledge, ultra‐structural hair alterations in FRDA were not demonstrated. The purpose of this study was to determine ultra‐structural alterations in the hairs of FRDA patients as well as carriers. Hair specimen from four patients, who are in different stages of the disease, and two carriers were examined by scanning electron microscope. Thin and weak hair follicles with absence of homogeneities on the cuticular surface, local damages of the cuticular layer, cuticular fractures were detected in both carriers and patients, but these alterations were much more prominent in the hair follicles of patients. In addition, erosions on the surface of the cuticle and local deep cavities just under the cuticular level were observed only in patients. Indistinct cuticular pattern, pores on the cuticular surface, and presence of concavities on the hair follicle were also detected in patients in later stages of the disease. According to our results, progression of the disease increased the alterations on hair structure. We suggest that ultra‐structural alterations observed in hair samples might be due to oxidative stress caused by deficient frataxin expression in mitochondria. Microsc. Res. Tech. 78:731–736, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
87.
Health risk assessment of inorganic arsenic intake of Cambodia residents through groundwater drinking pathway 总被引:3,自引:0,他引:3
Kongkea Phan Suthipong Sthiannopkao Kyoung-Woong Kim Ming Hung Wong Jamal Hisham Hashim Syed Mohamed Aljunid 《Water research》2010,44(19):5777-5788
In order to compare the magnitudes and health impacts of arsenic and other toxic trace elements in well water, groundwater and hair samples were collected from three areas with different arsenic exposure scenarios in the Mekong River basin of Cambodia. Ampil commune in Kampong Cham province was selected as an uncontaminated area, Khsarch Andaet commune in Kratie province was selected as a moderately contaminated area, and Kampong Kong commune in Kandal Province was selected as an extremely contaminated area. Results of ICP-MS analyses of the groundwater samples revealed that As, Mn, Fe and Ba concentrations were significantly different among the three study areas (Kruskal-Wallis test, p < 0.0001). Out of 46 observed wells in the Kandal province study area, 100% detected As > 50 μg L−1 and Fe > 300 μg L−1; 52.17% had Mn > 400 μg L−1 and 73.91% found Ba > 700 μg L−1. In the Kratie province study area (n = 12), 25% of wells showed elevated arsenic levels above 10 μg L−1 and 25% had Mn > 400 μg L−1, whereas samples from Kampong Cham province study area (n = 18) were relatively clean, with As < 10 μg L−1. A health risk assessment model derived from the USEPA was applied to calculate individual risks resulting from drinking groundwater. Computational results indicated that residents from Kandal Province study area (n = 297) confronted significantly higher non-carcinogenic and carcinogenic risks than those in Kratie (n = 89) and Kampong Cham (n = 184) province study areas (Kruskal-Wallis test, p < 0.0001). 98.65% of respondents from the Kandal province study area were at risk for the potential non-cancer effect and an average cancer risk index was found to be 5 in 1000 exposure. The calculations also indicated that, in the Kratie province study area, 13.48% of respondents were affected by non-cancer health risks and 33.71% were threatened by cancer, whereas none of respondents in the Kampong Cham province study area appeared to have non-carcinogenic effect. Positively significant correlations of the arsenic content in scalp hair (Ash) with both arsenic levels in groundwater (Asw) (rs (304) = 0.757, p < 0.0001) and individual average daily doses (ADD) of arsenic (rs (304) = 0.763, p < 0.0001) undoubtedly indicated that arsenic accumulation in the bodies of Cambodia residents in the Mekong River basin was mainly through a groundwater drinking pathway. To the best of our knowledge, this is the first comprehensive report comparing individual health risk assessments of arsenic exposure through a groundwater drinking pathway to enriched arsenic levels from groundwater in the Mekong River basin, Cambodia. This study indicates that elevated arsenic concentrations in groundwater may lead to thousands of cases of arsenicosis in the near future if mitigating actions are not taken. 相似文献
88.
结合实际总结了目前家庭室内设计存在的一些问题,鉴于此提出住宅室内设计要虚实结合、充分利用空间,并应注重考虑风格、形式,进而明确了住宅室内设计与装修的关系。 相似文献
89.
针对当前部分建筑形象丧失了作为人类生存内在基础的意义深度,淡漠了建筑初始含义的现状,通过对中国建筑现象进行分析,提出了重新建立建筑审美观的思路,进而还原建筑作为实体最初的美学意义。 相似文献
90.
拉伸-定形处理对人发强伸性能的影响 总被引:2,自引:0,他引:2
人发及羊毛等角蛋白纤维经拉伸一定形处理后,其强伸性能发生了一定的变化。文中系统地研究了拉伸处理及拉伸一定形处理对人发强伸性能的影响。结果表明,毛发拉伸保护剂对人发纤维具有明显地保护作用,从而使该拉伸改性工艺在较短的时间内得到较高的定形效果和较好的综合机械性能。 相似文献