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1.
The rapid development of the petrochemical industry of Taiwan over the past four decades has resulted in a booming economy in Taiwan that drives derived industries to develop progressively. However, it has also caused many runaway reaction accidents, such as toxic gas release, fire, and explosion. It is crucial to eliminate those potential hazard factors which can induce consequent runaway reaction accidents during the life span of the manufacturing process. In response to this crucial issue, we performed a thermokinetic parameter analysis for 1,1-bis-(tert-butylperoxy)-3,3,5-trimethylcyclohexane at isothermal conditions to conduct a thermal safety assessment of chemical materials. The five isothermal temperatures, 90, 100, 110, 120, 130, and 140 °C, measured by DSC, were adopted in this study to calculate process safety parameters, including TMRad, T NR, and SADT, which can be employed in process safety parameters for the manufacturing process. A novel, green kinetic approach accompanied with non-isothermal DSC results is used to derive thermokinetic parameters in safety protocol in this study.  相似文献   
2.
通过水热合成的方法制得具有三维超分子结构的2种配位聚合物{[Zn(L)(bpa)0.5(H2O)2]·2.25H2O}n1)和{[Cd(L)(H2O)]·2H2O}n2),其中,H3LCl为氯化5-(4-羟基吡啶基甲基)间苯二甲酸,bpa为1,2-二(4-吡啶基)乙烷。这2种化合物的结构通过单晶X射线衍射、红外光谱(IR)、元素分析、热重分析(TG)等方法进行了表征。结构解析表明:化合物1是一种梯型链式结构,并通过链间氢键作用延伸成了3D超分子网络;化合物2为含有大量一维隧道空腔的2D配位网络。此外,研究了这2种化合物的荧光性质。  相似文献   
3.
The problem of testing for umbrella alternatives in a one-way layout with right-censored survival data is considered. Testing procedures based on the two-sample weighted Kaplan-Meier statistics suggested by Pepe and Fleming (1989, Biometrics, 45, 497–507; 1991, J. Roy. Statist. Soc. Ser. B, 53, 341–352) are suggested for both cases when the peak of the umbrella is known or unknown. The asymptotic relative efficiency of the weighted Kaplan-Meier test and the weighted logrank test proposed by Chen and Wolfe (2000, Statist. Sinica, 10, 595–612) is computed for the umbrella peak-known setting where the piecewise exponential survival distributions have the proportional or crossing hazards, or the related hazards differ at early or late times. Moreover, the results of a Monte Carlo study are presented to investigate the level and power performances of the umbrella tests. Finally, application of the proposed procedures to an appropriated data set is illustrated.  相似文献   
4.
This report examines reactions of a series of Ir complexes supported by the diarylboryl/bis(phosphine) PBP pincer ligand with ethylene: (PBP)IrH4 (1), (PBP)IrH2(CO) (2), and (PBP)Ir(CO)2 (3). The outcomes of these reactions differ from those typical for Ir complexes supported by other pincer ligands and do not give rise to simple ethylene adducts or products of insertion of Ir into the C–H bond of ethylene. Instead, the elements of ethylene are incorporated into the molecules to result in B–C bonds. In the case of 2 and 3, ethylene addition results in the formation of B/Ir bridging ethylidene complexes 5 and 6. For 6, the addition of ethylene (and the analogous addition of 1-hexene) is shown to be partially reversible. Addition of ethylene to 2 and 3 is remarkable because they are saturated at Ir and yet the net outcome is such that ethylene binds without replacing any ligands already present. A mechanistic inquiry suggests that dissociation of CO from 3 or 6 is necessary in order for the addition or loss of ethylene to proceed.

(PBP)Ir pincer complexes containing a boryl-iridium linkage reversibly bind ethylene as an ethylidene bridging B and Ir.  相似文献   
5.
N3染料对F-的高选择性光学传感性质   总被引:1,自引:0,他引:1  
采用紫外-可见吸收光谱和荧光光谱滴定方法研究了N3染料, cis-Ru(H2dcbpy)2(NCS)2 (H2dcbpy=4,4’-二羧酸-2,2’-联吡啶), 在二甲基亚砜(DMSO)溶液中对F-、Cl-和Br-的识别行为. 结果表明, F-能引起N3的吸收光谱和荧光光谱的明显变化, 能作为高选择性的荧光和比率色度F-传感器. N3与F-相互作用产生一个大的荧光增强因子40, 在已报道的基于Ru(II)配合物的F-传感器中较为罕见.  相似文献   
6.
采用水热合成的方法,在以5-(4-羟基吡啶基甲基)间苯二甲酸(H2L)作主配体、4,4’-联吡啶(4,4’-bpy)和1,2-二(4-吡啶基)乙烯(bpe)作辅配体的条件下,得到2种新颖的Zn(Ⅱ)配位聚合物{[Zn(L)(4,4’-bpy)0.5]·2H2O}n1)和{[Zn(L)(bpe)0.5]·2H2O}n2)。配合物通过单晶X射线衍射的方法进行了结构分析,并进一步通过红外光谱(IR)、元素分析、PXRD和热重分析(TG)的方法进行了表征。结构分析表明配合物1展现出的是一种三维三重互穿网络;聚合物2为二维双层结构,并进一步组合成了三重平行互穿的2D→3D的空间网络。此外,研究了配合物的荧光性质。  相似文献   
7.
8.
Yu BY  Kuo CH  Wang WB  Yen GJ  Iida S  Chen SZ  Lin WC  Lee SH  Kao WL  Liu CY  Chang HY  You YW  Chang CJ  Liu CP  Jou JH  Shyue JJ 《The Analyst》2011,136(4):716-723
The nanostructure of the light emissive layer (EL) of polymer light emitting diodes (PLEDs) was investigated using force modulation microscopy (FMM) and scanning time-of-flight secondary ion mass spectrometry (ToF-SIMS) excited with focused Bi(3)(2+) primary beam. Three-dimensional nanostructures were reconstructed from high resolution ToF-SIMS images acquired with different C(60)(+) sputtering times. The observed nanostructure is related to the efficiency of the PLED. In poly(9-vinyl-carbazole) (PVK) based EL, a high processing temperature (60 °C) yielded less nanoscale phase separation than a low processing temperature (30 °C). This nanostructure can be further suppressed by replacing the host polymer with poly[oxy(3-(9H-9-carbazol-9-ilmethyl-2-methyltrimethylene)] (SL74) and poly[3-(carbazol-9-ylmethyl)-3-methyloxetane] (RS12), which have similar chemical structures and energy levels as PVK. The device efficiency increases when the phase separation inside the EL is suppressed. While the spontaneous formation of a bicontinuous nanostructure inside the active layer is known to provide a path for charge carrier transportation and to be the key to highly efficient polymeric solar cells, these nanostructures are less efficient for trapping the carrier inside the EL and thus lower the power conversion efficiency of the PLED devices.  相似文献   
9.
Journal of Thermal Analysis and Calorimetry - 1,1-Bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane (TMCH), an industrial initiator and cross-linking agent comprising two active peroxy bonds,...  相似文献   
10.
Shih WC  Chen WC  Lai YC  Yu MS  Ho JJ  Yap GP  Ong TG 《Organic letters》2012,14(8):2046-2049
We have disclosed a new mode of a chemically regioselective switch for C-H bond functionalization of benzimidazole derivatives via a cooperative effect invoked by Ni-Al bimetallic catalysis to create a steric requirement for obtaining the linear product of styrene insertion. Yet, excluding the AlMe(3) cocatalyst switches the reaction toward branch selectivity.  相似文献   
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