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51.
利用烧杯试验研究了一种新型磁性离子交换树脂(MIEX)对水中溴离子的去除效能,并考察了水中常见阴离子及有机物对其去除效果的影响。试验结果表明,MIEX可以有效去除纯水中的溴离子,投加量为10 mL/L和20 mL/L时其对溴离子去除率均在90%以上,且达到交换平衡时间分别为5 min和3 min。水中常见的其它带负电物质会在一定程度上影响溴离子的去除效果,在常见的含量条件下10 mL/L的MIEX对溴离子的去除率一般在50%以上。阴离子含量以及MIEX的选择性是影响其对溴离子去除效果的主要因素。有机物的存在使MIEX对溴离子的去除率明显下降,去除率在70%左右。MIEX对有机物、阴离子的去除过程存在差异:10 mL/L的MIEX去除阴离子的反应平衡时间在5 min左右,而去除有机物的平衡时间则较长,其对2种表征有机物含量的指标(UV 254、DOC)的去除稳定时间均在20 min以上。 相似文献
52.
负离子功能整理剂及用于家居的整理织物,会持续发生负离子,中和空气中正离子,起到净化空气、促进血液循环、抗菌除臭、远红外蓄热等作用.探讨了负离子远红外整理剂的制备及在纺织上的应用. 相似文献
53.
In this work, a fundamental study of ionic liquids (ILs) is shown. The main goal was to establish relationships between rheological and tribological properties of ILs and to understand how these properties are linked to the molecular structure of ILs. Of particular interest were the effects occurring to a frictional system due to variations of the anions and the alkyl chain length of the imidazolium‐based cations. Tribological experiments were performed using a reciprocating ball‐on‐disc test machine. To understand the effects resulting from a variation of the structural characteristics of the used ILs on the rheological properties, studies were performed using a rheometer. The results obtained are very promising in terms of improving friction and wear behaviour by using ILs as lubricants. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
54.
The template effect controlling the structure and morphology of ultrafine particles was described. Ni(OH)2 powders were prepared by NH3 coordination-precipitation method. The effects of SO
4
2−
, NO
3
−
, Cl−, NH3, pH value on Ni(OH)2 structure and morphology were investigated experimentally, explained with the theoretical model that the growth units were
the polyhedral structure of coordination anions. The results showed that the structure and morphology of Ni(OH)2 were effectively controlled by the growth units, the dimensions and the linking patterns of the growth units vary with the
changes of physical and chemical conditions in the aqueous solution.
Foundation item: The National Natural Science Foundation of China(No.59774018)
Biography of the first author: LIU Zhi-hong, professor, born in 1963, majoring in hydrometallurgical technology and control of structure and morphology
of powders. 相似文献
55.
用姐妹染色单体交换(SCE)作为指标,研究了~(60)Coγ射线辐照及NADH-PMS(吩嗪硫酸甲酯)系统中产生的超氧阴离子自由基(0_2~(·-))对胎儿脐血淋巴细胞染色体的损伤作用,及活性氧清除剂SOD和甘露醇的保护作用。结果显示γ射线及0_2~(·-)都能诱发细胞SCE频率显著升高,且存在一定的剂量-效应关系。SOD及甘露醇对0_2~(·-)诱发的损伤有明显的保护作用。 相似文献
56.
磷是一种不可再生资源。为解决现有磷污染以及磷资源流失等问题,通过油浴与热化学还原相结合的方法,成功制备出一种NiFe-LDH/rGO电活性杂化膜材料。使用电化学方法,在氧化还原电位的控制下,Ni、Fe(Ⅱ/Ⅲ)双金属发生核外电子的跃迁,高价态的Ni、Fe(Ⅲ)与 发生内球络合作用,实现 的选择性置入-置出。实验获得270 mg·g-1的高 吸附容量及85%以上的再生效率。此外,该杂化膜材料在共存离子存在的复杂水体中,对 具有优异的选择性,为磷石膏渗滤液以及各种含磷废水污染等问题的解决提供有效的理论技术支撑,具有广阔的应用前景。 相似文献
57.
58.
在SiO2-Al2O3-K2O-DAH-H2O(1,6-己二胺,DAH)体系中,研究水热合成条件对ZSM-22沸石相对结晶度和相纯度的影响。采用X射线衍射(XRD)和电感耦合等离子体(ICP)技术表征合成产物的结构、物相及化学组成。结果表明,合成胶n(SiO2)/n(Al2O3)在80~110,n(OH-)/n(SiO2)在0.33~0.35和433~438K条件下,合成出系列相纯度较高的ZSM-22沸石。产物相对结晶度和相纯度依赖于合成胶硅铝物质的量比、碱度和晶化温度。适当升高晶化温度有利于提高产物的相纯度和相对结晶度;n(SiO2)/n(Al2O3)在80~110之外,合成胶硅铝物质的量比的降低或提高分别导致ZSM-5或方石英相分率的逐渐增加。此外,纯ZSM-22骨架n(Si)/n(Al)分布于41.8~53.4;与n(SiO2)/n(Al2O3)关联可知,n(Si)/n(Al)比值向该区间中心呈收敛趋势。 相似文献
59.
It is well known that the studies of the evolution of biased movement along a resource gradient could create very interesting phenomena. This paper deals with a general two-species Lotka–Volterra competition model for the same resources in an advective nonhomogeneous environment, where the individuals are exposed to unidirectional flow (advection) but no individuals are lost through the boundary. It is assumed that the two species have the same population dynamics but different diffusion and advection rates. It is shown that at least five scenarios can occur (i) If one with a very strong biased movement relative to diffusion and the other with a more balanced approach, the species with much larger advection dispersal rate is driven to extinction; (ii) If one with a very strong biased movement and the other is smaller compare to its diffusion, the two species can coexist since one species mainly pursues resources at places of locally most favorable environments while the other relies on resources from other parts of the habitat; (iii) If both of the species random dispersal rates are sufficiently large (respectively small), two competing species coexist; (iv) If one with a sufficiently large random dispersal rate and the other with a sufficiently small one, two competing species still coexist; (v) If one with a sufficiently small random dispersal rate and the other with a suitable diffusion, which causes the extinction of the species with smaller random movement. Where (iii), (iv) and (v) show the global dynamics of (5) when both of the species dispersal rates are sufficiently large or sufficiently small. These results provide a new mechanism for the coexistence of competing species, and they also imply that selection is against excessive advection along environmental gradients (respectively, random dispersal rate), and an intermediate biased movement rate (respectively, random dispersal rate) may evolve. Finally, we also apply a perturbation argument to illustrate the evolution of these rates. 相似文献
60.
目视法检测阴离子用显色剂的研究进展 总被引:2,自引:1,他引:2
评述了以超分子化学分子识别为基础发展起来的新型阴离子目视显色剂,内容主要包括显色剂对选择性阴离子的显色属性以及显色属性和显色剂结构的关系. 相似文献