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991.
Raquel Martín-Venegas M.Teresa Brufau Ana Maria Guerrero-Zamora Yves Mercier Pierre-André Geraert Ruth Ferrer 《Food chemistry》2013
dl-2-hydroxy-(4-methylthio)butanoic acid (HMTBA) is a source of dietary methionine (Met) that is widely used in poultry nutrition. We have previously shown that HMTBA is preferentially diverted to the transsulfuration pathway, which gives antioxidant metabolites such as taurine and glutathione. Therefore, here we hypothesize that this Met source can protect epithelial barrier function in an in vitro model of intestinal inflammation of Caco-2 cells. The results show that HMTBA prevents the increase in paracellular permeability induced by H2O2 or tumour necrosis factor-α. This effect can be attributed to the increased production of taurine and reduced glutathione. Similar results were obtained for dl-Met, although the protective role of the amino acid was less pronounced than that of the hydroxy analogue. In conclusion, the diversion to the transsulfuration pathway means that this Met precursor is of greater value than previously thought, due to its capacity to improve intestinal homeostasis and the quality of poultry products destined for human consumption. 相似文献
992.
993.
Hongbin Pu Lian Lin Da‐Wen Sun 《Comprehensive Reviews in Food Science and Food Safety》2019,18(4):853-866
Hyperspectral imaging (HSI) techniques play an important role in the food industry for providing rapid, nondestructive, and chemical‐free detection method, whereas a microscope can provide detailed information about the microstructure of a food item. As an emerging imaging spectroscopy technique, hyperspectral microscope imaging (HMI) technique combines the advantages of HSI with microscopic imaging and has been gradually applied in the food industry. This review introduces the principles of different kinds of HMI techniques, such as fluorescence HMI, visible/near‐infrared HMI, Raman HMI, and infrared HMI. Moreover, detailed applications of HMI techniques are summarized, including evaluation of structures of nutrients, and detection of microorganisms and residues. On the other hand, some challenges and future trends in the applications of these techniques are also discussed. It is concluded that by integrating HSI with microscopy, HMI can not only provide both spectral and spatial information about food substances but also provide their chemical information at the molecular or cellular level. Therefore, HMI techniques have great potentials in nondestructive evaluation of structures of nutrients, and detection of microorganisms and residues for the food industry. 相似文献
994.
Tatiana Koutchma 《Food and Bioprocess Technology》2009,2(2):138-155
A negative, public reaction is growing over the addition of chemical preservatives to liquid foods and beverages to extend
their shelf life and to protect against foodborne pathogens. As a physical method, ultraviolet light (UV) irradiation has
a positive consumer image and is of interest to the food industry as a low cost non-thermal method of preservation. Recent
advances in the science and engineering of UV light irradiation have demonstrated that this technology holds considerable
promise as an alternative to traditional thermal pasteurization for liquid foods and ingredients, fresh juices, soft drinks,
and beverages. However, its use for treating foods is still limited due to low UV transmittance of liquid foods. The goal
of this review is to provide a summary of the basic principles of UV light generation and propagation with emphasis on its
applications for liquid food processing. The review includes information on critical product and process factors that affect
UV light inactivation and consequently the delivery of a required scheduled process in liquids foods; measuring and modeling
of UV inactivation, and the important effects of UV light on overall quality and nutritional value of liquid foods. The commercially
available UV light sources and UV reactor designs that were used for liquid foods treatment are reviewed. The research priorities
and challenges that need to be addressed for the successful development of UV technology for liquid foods treatment are discussed. 相似文献
995.
针对红外与微光图像配准的特殊性,
为了减少配准计算量,提出了一种从主方向确定和特征点描述
两方面加以改进的加速鲁棒特征(Speeded Up Robust Feature, SURF)配
准算法。首先检测微光图像和红外图
像的边缘,然后用改进型SURF算法提取两种图像边缘上的特征
点,并采用最近邻距离法对原始特征点进行筛选。在得到较高精
度的特征点后进行粗匹配。接着用随机抽样一致
性(RANdom SAmple Consensus, RANSAC)算法对一次筛选后的
特征点进行精匹配。最后利用精确的特征点建立变换模型,并
将重采样后的待配准图像与参考图像实现配准。实验结果表明,
该算法不仅可以解决红外与微光图像的配准问题,而且在匹配精度和
算法运算时间等方面的表现均优于原始SURF算法。 相似文献
996.
扩展青霉 (Penicillium expansum)和指状青霉(Penicillium digitatum)是两种典型采后致病菌,其中扩展青霉能够引起苹果、梨、猕猴桃、樱桃等水果的采后贮藏期腐烂,指状青霉则是引起柑橘类水果采后及贮藏期间腐烂的主要致病菌之一。为明确两株青霉菌生长及产酸的适宜环境条件,本试验对不同营养、温度、pH值、光照等条件下青霉菌的生长情况进行了研究。结果表明,在实验给定的条件下,最适宜扩展青霉生长和产酸的培养基为马铃薯葡萄糖琼脂培养基,温度分别为25℃和20℃,pH分别为4和10,均为黑暗环境;最适宜指状青霉生长和产酸的培养基为马铃薯葡萄糖琼脂培养基,温度均为20℃,pH分别为4和8,均为黑暗环境。这为后续对两株菌株产酸及致病性的探究提供科学依据。 相似文献
997.
介绍了双向反射分布函数的测量原理和方法,搭建了双向反射分布函数的测量装置。该装置可以测量可见光和红外两个波段的双向反射分布函数。在可见光波段采用卤钨灯作为光源,采用光纤光谱仪作为光接收器,以10 nm的波长间隔测量双向反射分布函数。在红外波段采用碳化硅作为红外光源,采用热释电探测器作为光接收器,采用标准板相对定标的方法测量待测样板的双向反射分布函数。可见光波段双向反射分布函数的测量重复性不大于1.5%;3μm~5μm红外波段双向反射分布函数的测量重复性分别小于或等于2.5%、8μm~12μm波段的小于或等于3.0%。测量结果表明,该测量装置的有效性较高。 相似文献
998.
999.
The effect of ultraviolet processing (10.6 and 63.7 kJ m(-2)) on selected properties of egg white (absorbance, particle size, protein fractions, free sulfhydryl content, immunoreactivity, viscosity, gelling and foaming properties) was investigated. Ultraviolet exposure induced the development of browning, the formation of large protein aggregates by disulfide exchange, and protein backbone cleavage. However, egg white proteins were differently sensitive to UV radiation. No changes in immunoreactivity, gelling temperature and gel firmness were observed. Independently on the UV dose, light treated egg white produced foams with higher stability. This effect was attributed to protein aggregates jamming in the fluid interstices between bubbles and/or to the higher viscosity of the aqueous phase. The latter was also associated to higher foam volume. 相似文献
1000.