• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.57-60
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• 1991

Benzosilacyclobutenes were prepared from the reactions of 1,1-dichlorobenzosilacyclobutene with Grignard reagents or t-butyllithium. In the thermal reactions with alcohols, benzosilacyclobutenes underwent both benzyl-silicon and aryl-silicon bond rupture to yield (dialkyl)alkoxy-o-tolylsilanes and (dialkyl)alkoxybenzylsilanes, respectively. The photochemical reactions, however, produced only the former products via o-silaquinone methides.

• 대한화학회지
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• 제18권6호
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• pp.447-452
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• 1974

多數의 熱共重合 反應組들에 對하여 pseudo molecular complex 形成이 可能한가를 理論的으로 調査하였던바 例外없이 pseudo molecular complex 形成이 가능하였다. 卽, pseudo molecular complex 形成이 共重合反應組들의 共通性임을 발견하였다. 그래서 熱共重合反應은 pseudo molecular complex를 경유하여 反應이 進行하는 하나의 可能한 開始機構를 提案하였다.

• Bulletin of the Korean Chemical Society
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• 제20권7호
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• pp.801-804
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• 1999

Thermal and photoinduced silylallylation reactions of organic halides with 3-stannyl-2-(silylmethyl)propene are explored. Silylallylations occur in moderate to high yields, producing various functionalized allylsilane products in which halide carbon is bonded to the terminal alkenic carbon of allylsilane with the removal of tributyltin group. The reactions, which tolerate functional groups such as carbonyl, ester, nitrile, acetal, and ketal, hold synthetic potential for the construction of functionalized allylsilanes.

• 대한지리학회지
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• 제32권2호
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• pp.129-140
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• 1997

본 논문에서는 인간 생리 및 생활에 가장 기본이 되는 온도, 상대습도를 기초로 하여 인간의 열긴장도를 측정하여 우리나라의 열감분포의 특성을 파악하였다. 연구 방법은 열지수 분석을 중심으로 하였다. 열지수는 습도계산도에서, 월별 열지수 및 연누적 열지수를 계산하여 한국의 연누적 열지수 분포도를 작성하였다. 연누적 열지수 분포의 분석 결과는 우리 나라의 대부분 지역이 한랭긴장도가 나타나는 지역이고 남쪽에서 북쪽으로, 해안에서 내륙으로 갈수록 한랭긴장도가 높아지고 있다. 특히 삼지연. 풍산, 장진을 중심으로 한 개마고원 지역이 높은 한랭긴장도 지역이고, 제주와 서귀포룰 포함한 제주도 지역이 가장 낮은 긴장도를 보이고 있다. 전자는 겨울에 시베리아 기단의 영향을 직접 받고. 고도가 매우 높은 내륙 산지 지역이기 때문이고, 후자는 위도와 바다의 영향으로 특히 겨울에 온화한 지역이기 때문이다.

• 대한화학회지
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• 제11권2호
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• pp.70-76
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• 1967

Structural changes attending polyacrylonitrile(PAN) upon heating and treating with nucleophilic reagents have been studied for some time and a few authors have studied on the thermal degradation, particularly on the characterization of degradation products in PAN. It is the purpose of this paper to report the kinetic study on the thermal degradation above $250^{\circ}C$ and make some suggestions as to the degradation process and mechanism in PAN. The degradation process in PAN is considered that three reactions are combined in two steps. Random chain scission accompanying the naphthylidine-type ring formation is the first step and the degradation of naphthylidine-type ring occurred as the next step. The reactions in the first step are competitive so that the maximum weight loss on pyrolysis of PAN, under such a condition that the degradation of naphthylidine-type ring is negligible, is depended on the relative reaction rate of these two competitive reactions.

• Bulletin of the Korean Chemical Society
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• 제6권4호
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• pp.206-209
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• 1985

The gas phase reactions of the photochemically generated t-butoxy radicals with phosphine ($PH_3$) were studied in the temperature range of $35-80^{\circ}C.$ We found the significant differences between high temperature thermal reactions and low temperature photo reactions. In comparison with the reactions of t-butoxy radicals with other hydrogen donors, some possible mechanistic suggestions were made for the explanation of the results.

• Journal of Photoscience
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• 제9권1호
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• pp.1-4
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• 2002

This brief review deals with the thermal or photochemical synthesis and reactions of silacyclopropene or 1-sila-1,2-propadiene. The novel intramolecular reactions of silacyclopropene or 1-sila-1,2-propadiene are also discussed.

• Fibers and Polymers
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• 제4권4호
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• pp.195-198
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• 2003

Epoxidized polybutadiene (EPB) was prepared by polybutadiene (PB) with m-chloroperbenzoic acid (MCPBA) in homogeneous solution. EPB was blended with poly(3-hydroxybutyrate) (PHB) up to 30 wt% by solution-precipitation procedure. The thermal decomposition of PHB/EPB blends was studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and differential thermal analysis (DTA). The thermograms of PHB/EPB blends contained a two-step degradation process, while that of pure PHB sample exhibited only one-step degradation process. This degradation behavior of PHB/EPB blends, which have a higher thermal stability as measured by maximum decomposition temperature and residual weight, is probably due to crosslinking reactions of the epoxide groups in the EPB component with the carboxyl chain ends of PHB fragments during the degradation process, and the occurrence of such reactions can be assigned to the exothermic peaks in their DTA thermograms.

• 한국안전학회지
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• 제25권3호
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• pp.61-65
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• 2010

Most of the chemical reactions performed in the chemical industry are exothermic, meaning that thermal energy is released during the reaction. It is also important to understand the thermal hazards such as thermal stabilities and runaway reactions, which are governed by thermodynamics and reaction kinetics of the mixed materials. The paper was described the evaluation of thermal behavior caused by an exothermic batch process in manufacture of the vinyl acetate resin. The aim of the study was to evaluate the thermal stabilities of raw materials with operating conditions such as a reaction inhibitor, heating rate, reaction atmosphere and the mount of methanol charged in the vinyl acetate polymerization process. The experiments were performed in the differential scanning calorimeter(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). It was suggested that we should provide the thermal characteristics for raw materials to present safe precautions with operating conditions in the vinyl acetate polymerization process.

• Journal of Electrochemical Science and Technology
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• 제7권2호
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• pp.179-184
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• 2016

The interface between the surface of a cathode material and the electrolyte gives rise to surface reactions such as solid electrolyte interface (SEI) and chemical side reactions. These reactions lead to increased surface resistance and charge transfer resistance. It is consequently necessary to improve the electrochemical characteristics by suppressing these reactions. In order to suppress unnecessary surface reactions, we coated cathode material using polypropylene (PP). The PP coating layer effectively reduced the SEI film that is generated after a 4.3 V initial charging process. By mitigating the formation of the SEI film, the PP-coated Li[(Ni_0.6Co_0.1Mn_0.3)_0.36(Ni_0.80Co_0.15Al0.05)_0.64)]O₂(NCS) electrode provided enhanced transport of Li⁺ ions due to reduced SEI resistance (R_SEI) and charge transfer resistance (R_ct). The initial charge and discharge efficiency of the PP-coated NCS electrode was 96.2 % at a current density of 17 mA/g in a voltage range of 3.0 ~ 4.3 V, whereas the efficiency of the NCS electrode was only 94.7 %. The presence of the protective PP layer on the cathode improved the thermal stability by reducing the generated heat, and this was confirmed via DSC analysis by an increased exothermic peak.