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821.
S. P. Solodovnikov E. G. Gal'pern I. V. Stankevich A. L. Chistyakov 《Russian Chemical Bulletin》1999,48(7):1246-1249
Electronic structure of the C120
·+ radical cation and the paramagnetic C120O2+ dication and C120O2− dianion in the triplet state was calculated by the MNDO/PM3 method in the valence approximation. The density distributions
of the unpaired electrons in these systems were found and the ESR spectra of the above species were interpreted.
Translated fromIzvestiya Akademii Nauk Seriya Khimicheskaya, No. 7, pp. 1257–1260, July, 1999. 相似文献
822.
Dr. Anzhela Galstyan Dr. Yogesh Kumar Maurya Dr. Halina Zhylitskaya Youn Jue Bae Dr. Yi-Lin Wu Prof. Dr. Michael R. Wasielewski Prof. Dr. Tadeusz Lis Prof. Dr. Ulrich Dobrindt Prof. Dr. Marcin Stępień 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(37):8262-8266
Free base, zinc and palladium π-extended porphyrins containing fused naphthalenediamide units were employed as photosensitizers in antimicrobial photodynamic therapy (aPDT). Their efficacy, assessed by photophysical and in vitro photobiological studies on Gram-positive bacteria, was found to depend on metal coordination, showing a dramatic enhancement of photosensitizing activity for the palladium complex. 相似文献
823.
824.
深紫外光刻照明系统扩束单元设计 总被引:2,自引:2,他引:0
在曝光线宽为90nm的投影光刻机中,准分子激光光源发出的矩形截面光束,需要进行一维扩束,以获得光束整形单元所需的正方形截面分布。现有的这类扩束单元分别存在严重的相干散斑效应和严格的装调公差等不足。基于此,提出了多组元平行反射扩束镜组。通过求解各组元透射率值的线性方程组,得到若干种扩束单元结构,其中的四组元扩束单元每个组元只有一种透射率,有效降低了镀膜的工艺成本。分别从公差分析、系统透射率和出射光束均匀性等方面对各类扩束单元结构进行综合比较,并通过建模仿真,验证了设计的四组元扩束单元的散斑效应和装调公差灵敏度都明显降低,而且出射光束较均匀,有利于提高照明均匀性。 相似文献
825.
826.
827.
828.
Biomass pyrolysis kinetics: A comparative critical review with relevant agricultural residue case studies 总被引:5,自引:0,他引:5
John E. White W. James Catallo Benjamin L. Legendre 《Journal of Analytical and Applied Pyrolysis》2011,91(1):1-33
Biomass pyrolysis is a fundamental thermochemical conversion process that is of both industrial and ecological importance. From designing and operating industrial biomass conversion systems to modeling the spread of wildfires, an understanding of solid state pyrolysis kinetics is imperative. A critical review of kinetic models and mathematical approximations currently employed in solid state thermal analysis is provided. Isoconversional and model-fitting methods for estimating kinetic parameters are comparatively evaluated. The thermal decomposition of biomass proceeds via a very complex set of competitive and concurrent reactions and thus the exact mechanism for biomass pyrolysis remains a mystery. The pernicious persistence of substantial variations in kinetic rate data for solids irrespective of the kinetic model employed has exposed serious divisions within the thermal analysis community and also caused the broader scientific and industrial community to question the relevancy and applicability of all kinetic data obtained from heterogeneous reactions. Many factors can influence the kinetic parameters, including process conditions, heat and mass transfer limitations, physical and chemical heterogeneity of the sample, and systematic errors. An analysis of thermal decomposition data obtained from two agricultural residues, nutshells and sugarcane bagasse, reveals the inherent difficulty and risks involved in modeling heterogeneous reaction systems. 相似文献
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830.
Phosphine Sulfide-Based Bipolar Host Materials for Blue Phosphorescent Organic Light-Emitting Diodes
Gaozhan Xie Jiangchao Wang Yang Cao Xudong Xue Xiao Zhang Chang Liu Huanhuan Li Ye Tao Runfeng Chen 《Molecules (Basel, Switzerland)》2021,26(13)
Three phosphine sulfide-based bipolar host materials, viz CzPhPS, DCzPhPS, and TCzPhPS, were facilely prepared through a one-pot synthesis in excellent yields. The developed hosts exhibit superior thermal stabilities with the decomposition temperatures (Td) all exceeding 350 °C and the melting temperatures (Tm) over 200 °C. In addition, their triplet energy (ET) levels are estimated to be higher than 3.0 eV, illustrating that they are applicable to serve as hosts for blue phosphorescent organic light-emitting diodes (PhOLEDs). The maxima luminance, current efficiency (CE), power efficiency (PE), and external quantum efficiency (EQE) of 17,223 cd m−2, 36.7 cd A−1, 37.5 lm W−1, and 17.5% are achieved for the blue PhOLEDs hosted by CzPhPS. The PhOLEDs based on DCzPhPS and TCzPhPS show inferior device performance than that of CzPhPS, which might be ascribed to the deteriorated charge transporting balance as the increased number of the constructed carbazole units in DCzPhPS and TCzPhPS molecules would enhance the hole-transporting ability of the devices to a large extent. Our study demonstrates that the bipolar hosts derived from phosphine sulfide have enormous potential applications in blue PhOLEDs, and the quantity of donors should be well controlled to exploit highly efficient phosphine sulfide-based hosts. 相似文献