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71.
J. Xing Z. -C. Tan Q. Shi B. Tong S. -X. Wang Y. -S. Li 《Journal of Thermal Analysis and Calorimetry》2008,92(2):375-380
Three different nitrocellulose (NC) samples produced from linters were investigated. DSC studies on the NC+sym-diethyldiphenylurea (C1) mixtures were carried out. The influence of storage time on their pore structures was examined using
thermoporometry. The results led to conclusion that large pores are multiples of small ones. The parameter n was used to characterize the number of C1 molecules equivalent to NC ring. Its value for short storage time was about 9 but
for longer time reached the value of 3. The influence of thermal history on the phase transition and porosity of the different
nitrocellulose samples was different. 相似文献
72.
蟹,虾壳微观形貌与结构研究 总被引:7,自引:0,他引:7
用X射线衍射与扫描电镜研究了蟹壳,虾壳的形貌与微观结构,蟹壳中以方解石晶型存在的碳酸钙分布在网状结构的有机质中,网孔的尺寸约5~25μm有机基质脱去蛋白后留下的甲壳质呈片层状结构,它的重复距离为0.96nm。 相似文献
73.
74.
Wang T Sha R Birktoft J Zheng J Mao C Seeman NC 《Journal of the American Chemical Society》2010,132(44):15471-15473
We describe the self-assembly of a DNA crystal that contains two tensegrity triangle molecules per asymmetric unit. We have used X-ray crystallography to determine its crystal structure. In addition, we have demonstrated control over the colors of the crystals by attaching either Cy3 dye (pink) or Cy5 dye (blue-green) to the components of the crystal, yielding crystals of corresponding colors. Attaching the pair of dyes to the pair of molecules yields a purple crystal. 相似文献
75.
低温等离子体与MnO_x/γ-Al_2O_3协同催化降解正己醛 总被引:2,自引:0,他引:2
研究了在低温等离子体和催化剂共同作用下低浓度正己醛的降解反应.结果表明,等离子体与γ-Al2O3之间产生了很好的催化协同作用,在低放电功率(2.8W)和低温(80℃)下,干燥空气气氛中,γ-Al2O3对0.12%正己醛的去除率为87.1%;当γ-Al2O3负载7.5%MnOx后,正己醛去除率达到96.5%,其效果与Pt/γ-Al2O3相当.7.5%MnOx/γ-Al2O3在实验条件下连续使用50h,其催化活性未见下降. 相似文献
76.
The mesoporous carbon material with large pore volume and high surface area by a simple situ MgO template method is synthesized, which is utilized as cathode to assemble a high performance lithium ion capacitor. 相似文献
77.
Abstract The zinc(II) complex with 2-(2-hydroxyphenyl)benzimidazole, namely [Zn(2-(2-hydroxyphenyl)benzimidazolate)2]·C2H5OH (1 · C2H5OH) has been synthesized and characterized by X-ray crystallography and photoluminescent analysis. The complex crystallizes
in monoclinic space group P21/c with cell parameters a = 10.156(1) ?, b = 25.771(3) ?, c = 9.674(1) ?, α = 90°, β = 103.641(2)°, γ = 90°, Z = 4, V = 2460.4(4) ?3. The central Zn(II) is four-coordinate and has a tetrahedral geometry. The steady-state and time-resolved photoluminescent
spectra for the title compound have also been studied. The emission property can be ascribed to ligand-centered charge-transfer
transition (LCCT) with π → π* property.
Index Abstract
A new co-crystal of Zn(II) complex of 2-(2-hydroxylphenyl)benzimidazole with ethanol solvate has been prepared, characterized
by X-ray crystallography and fluorescent studies.
相似文献
78.
为研究不同颗粒度对Al-teflon反应行为的影响,以颗粒度25μm、1μm和20~200 nm的Al粉和微米级Teflon粉混合制备的反应材料为研究对象,基于脉冲激光烧蚀实验,结合ICCD相机和光谱仪对反应过程中的自发光成像和发射光谱进行瞬态观测。研究结果表明,Al-teflon反应材料在激光烧蚀下的反应行为体现出典型的二次反应特征,具有持续燃烧特征和明显的后燃效应,也具有较长的能量释放时间;同时,其反应行为与Al粉颗粒度密切相关:初始阶段,反应随Al粉颗粒度的降低加剧,随着反应的进行,纳米级Al粉对应的反应材料后续反应能力逐渐下降,反应强度和反应时间都小于1μm铝粉对应的反应材料。 相似文献
79.
Weifeng Zhang Gaocai Li Rongjin Luo Jie Lei Yu Song Bingjin Wang Liang Ma Zhiwei Liao Wencan Ke Hui Liu Wenbin Hua Kangcheng Zhao Xiaobo Feng Xinghuo Wu Yukun Zhang Kun Wang Cao Yang 《Experimental & molecular medicine》2022,54(2):129
Low back pain (LBP) is a major musculoskeletal disorder and the socioeconomic problem with a high prevalence that mainly involves intervertebral disc (IVD) degeneration, characterized by progressive nucleus pulposus (NP) cell death and the development of an inflammatory microenvironment in NP tissue. Excessively accumulated cytosolic DNA acts as a damage-associated molecular pattern (DAMP) that is monitored by the cGAS-STING axis to trigger the immune response in many degenerative diseases. NLRP3 inflammasome-dependent pyroptosis is a type of inflammatory programmed death that promotes a chronic inflammatory response and tissue degeneration. However, the relationship between the cGAS-STING axis and NLRP3 inflammasome-induced pyroptosis in the pathogenesis of IVD degeneration remains unclear. Here, we used magnetic resonance imaging (MRI) and histopathology to demonstrate that cGAS, STING, and NLRP3 are associated with the degree of IVD degeneration. Oxidative stress induced cGAS-STING axis activation and NLRP3 inflammasome-mediated pyroptosis in a STING-dependent manner in human NP cells. Interestingly, the canonical morphological and functional characteristics of mitochondrial permeability transition pore (mPTP) opening with the cytosolic escape of mitochondrial DNA (mtDNA) were observed in human NP cells under oxidative stress. Furthermore, the administration of a specific pharmacological inhibitor of mPTP and self-mtDNA cytosolic leakage effectively reduced NLRP3 inflammasome-mediated pyroptotic NP cell death and microenvironmental inflammation in vitro and degenerative progression in a rat disc needle puncture model. Collectively, these data highlight the critical roles of the cGAS-STING-NLRP3 axis and pyroptosis in the progression of IVD degeneration and provide promising therapeutic approaches for discogenic LBP.Subject terms: Cell death, Diseases 相似文献
80.
As a typical screening apparatus,the elliptically vibrating screen was extensively employed for the size classification of granular materials.Unremitting effort... 相似文献