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ABSTRACT

In recent years, the exploration of a practical strategy for novel energetic molecules with high energy and low sensitivity is very desirable but highly challenging. Novel ionic energetic molecules have attracted much attention in this area due to their prominent advantages including low sensitivities, high thermal stability, and excellent energy performances. Herein, five different ionic energetic molecules based on new monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties with enhanced oxygen balance have been synthesized, characterized and evaluated as potential high-energy materials. Thermal stability, sensitivities and energy output test were measured and studied in detail. The heats of formation and energetic parameters were calculated by using Gaussian 09 suite of programs and EXPLO 5 code. The results suggest that all as-prepared new molecules exhibit good thermal stability with high decomposition temperature (3, 231°C; 5, 160°C; 6, 185°C; 7, 180°C; 8, 213°C), and relative low sensitivity (IS > 20 J, FS = 324 N). Inheriting the significant oxygen content of monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties, they also possess good energy properties (v D = 8238 ~ 9208 m s?1, P = 26.8 ~ 36.7 GPa, V o = 481.8 ~ 959.4 L kg?1), which make them competitive high-energy materials.  相似文献   
4.
Li  Zhenxing  Gong  Yixuan  Zhang  Xin  Wen  Yangyang  Yao  Jiasai  Hu  Mingliang  He  Miao  Liu  Jiahao  Li  Rui  Wang  Fuqiang  Zhang  Chuanxin 《Nano Research》2020,13(10):2812-2818

Carbon-carbon (C-C) coupling reactions represent one of the most powerful tools for the synthesis of complex natural products, bioactive molecules developed as drugs and agrochemicals. In this work, a multifunctional nanoreactor for C-C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8 (Cu@Ni@ZIF-8). In this nanoreactor, Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center, and Cu core was in situ heating source for the catalyst by absorbing the visible light. Moreover, benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8, the absorption range of nanoreactor was widened and the utilization rate of visible light was enhanced. Most importantly, the microporous structure of ZIF-8 provided shape-selective of reactant. This composite was used for the highly shape-selective and stable photocatalysed C-C coupling reaction of boric acid under visible light irradiation. After five cycles, the nanoreactor still remained high catalytical activity. This Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C-C coupling reactions with shape-selectivity.

  相似文献   
5.
ABSTRACT

Here, a novel cryogenic rolling plus intercritical annealing process was applied to a transformation-induced plasticity (TRIP) steel with a low chemical composition of carbon and manganese. Compared with traditional cold rolling, obvious grain refinement was observed, due to a high amount of dislocations retained. In addition, austenite volume fraction was increased, because of a unique nucleation mechanism. Subjected to cryogenic rolling, strength and ductility were increased, due to the enhanced austenite stability, which provided continuous and active TRIP effect. Consequently, tensile strength was increased to 1030?MPa, and elongation was increased to 38.2%. Thus, a great mechanical combination was obtained in a steel with a relatively low chemical composition with carbon and manganese, only by cryogenic rolling process.  相似文献   
6.
关于资源补偿费计算方法的探讨   总被引:3,自引:0,他引:3  
胡贵  汪应宏 《矿业快报》2007,23(11):4-7
在分别讨论了矿产资源价值、资源税、权利金和资源补偿费的基础上,明确了资源补偿费的基本内涵,并对1994颁布的《矿产资源补偿费征收管理规定》中的资源补偿费计算公式进行了分析、转换,提出矿产资源补偿费的理论计算方法。  相似文献   
7.
研究了以氧化镁和磷酸二氢钾反应所得的镁质磷酸盐水泥胶凝材料(MKP)为结合剂的高铝质浇注料的性能及影响该浇注料性能的诸因素。探索性研究发现:硅灰的用量是该浇注料体系850℃和1 100℃强度的主要影响因素,MKP胶凝体系的用量是110℃强度的主要决定因素,而1 100℃的线收缩率的主要影响因素是氧化镁和磷酸二氢钾的摩尔比值。并且此浇注料的强度不但与煅烧温度有关,而且还和氧化镁的活性有关,因此可以通过调节硼砂的量和氧化镁的活性来调节体系的可作业时间。  相似文献   
8.
现在大多数是建筑师和室内设计师分工协作,在一个空间设计中,两者谁占主导位置,其最后的空间感觉也就相应的偏向那一方,就设计本身而言没有什么对和错,好与坏,只要是适用的设计那就是合理的。  相似文献   
9.
This essay begins with a reflection on what has been taught in architectural design since the turn of the twentieth century. I shall trace back to the two disciplinary foundations of the French École des Beaux-Arts — parti and poché — in the education of an architect in the eighteenth and nineteenth centuries. I shall then attempt to superimpose parti and poché on a modern disciplinary framework, say that of mathematics, which leads to musings on a series of architectural problems that include pattern versus type, stability versus mobility, orthogonal versus oblique, confinement versus transparency, and aging versus metallic sheen. These paradoxes, I suggest, demand the education of an architect to address both the instrumental pattern of a building configuration and the ambient felt qualities of a room, rather than vision alone.  相似文献   
10.
The grain handling and transportation system (GHTS) has been a defining component of the western Canadian economy since the early part of the last century. Only two major railways serve the grain handling industry, so the potential for the exercise of market power in transportation appears to be significant. In fact, spatially oriented regulations applicable to railways exist in Canada to mitigate this, but to date they have not often been used by shippers. While the reasons for this are not completely clear, we suggest that the regulations are now inadequate for the current state of the GHTS. Using a unique data set from the year 2000, we assess the effect on the grain handling industry of modifications to these regulations, and find that significant gains for shippers from these modifications are possible. These gains are computed to be on the order of C$10–15 million per year for grain shippers alone. We would like to thank conference and presentation participants (Transportation Research Board, Canadian Agricultural Economics Society, University of British Columbia, University of Leeds and California State University, Long Beach) as well as the anonymous reviewers who commented on the earlier versions of this paper. We would also like to acknowledge support from the Saskatchewan Department of Highways.  相似文献   
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