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81.
82.
Russian Journal of Organic Chemistry - The alkylation of 2,2′-(methylenedisulfanediyl)- and 2,2′-(ethane-1,2-diyldisulfanediyl)bis-(1,3-benzothiazoles) with 1-iodopropan-2-one involves...  相似文献   
83.
84.

The solvent-free reaction of 1-iodomethyl-1,1,3,3,3-pentamethyldisiloxane with 1,2,4-triazole derivatives and 1,2,3-benzotriazole afforded organylcyclosiloxane iodides and triiodides. The reactions involved alkylation of pyridine and pyrrole nitrogens and cleavage of the siloxane bonds mediated by hydrogen iodide generated upon the reaction.

  相似文献   
85.
The thermal decomposition of corrugated cardboard has been studied in inert and oxidative (non-flaming) atmospheres under a range of radiant heat fluxes relevant to fire conditions in warehouse storage applications. Experiments were performed in a Fire Propagation Apparatus (FPA) on double-wall corrugated cardboard at heat flux levels of 20, 60, and 100 kW/m2. Pyrolysis data comprised of gasification rates and surface temperatures were collected for tests carried out in ambient atmospheres consisting of 100% N2 as well as 2%, 6%, 8%, 10%, and 14% (mol) O2 in balance nitrogen. It is shown that the presence of oxygen has an appreciable effect at all heat flux levels; however, it is most prevalent at low heat fluxes. Analyses are presented in an effort to gain further understanding of char oxidation processes. Results show that the maximum heat evolved in oxidative environments is relatively constant and similar for all conditions tested. Furthermore this heat release rate is found to be comparatively small relative to the high radiant fluxes tested; this explains the experimentally observed behavior. This study provides a comprehensive dataset that may be used in conjunction with approaches recently adopted in the fire community in which optimization procedures are employed to generate material properties for pyrolysis models used in CFD fire simulations.  相似文献   
86.
Changes in the structure and optical and electrical properties of Apical brand polyimide films under the action in air of accelerated electrons with an energy of 0.5 MeV and absorbed dose varied in the range 1–300 MGy were studied.  相似文献   
87.
Solvent-free reactions of 1,2,3-benzotriazole with 1-iodopropan-2-one and 1,3-diiodopropan-2-one in the absence of a catalyst involved alkylation of the heteroring at the N1 atom and subsequent quaternization at the N3 atom with formation of 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium triiodide which is a new conducting ionic liquid. The reaction of 1,2,3-benzotriazole with 1,3-diiodopropan-2-one was accompanied by reductive deiodination of the iodomethyl groups in the initial ketone with hydrogen iodide liberated by N1-alkylation. Triiodide ion readily exchanges for nitrate ion by the action of AgNO3 to produce 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium nitrate. The reaction of 1,2,3-benzotriazole with 2-iodo-1-phenylethan-1-one in melt resulted in the formation of 1,3-bis(2-oxo-2-phenylethyl)-1H-1,2,3-benzotriazolium triiodide.  相似文献   
88.
TeO2–WO3 (TW), TeO2–WO3–La2O3 (TWL), TeO2–WO3–La2O3–Bi2O3 (TWLB) and TeO2–ZnO–Na2O–Bi2O3 (TZNB) glasses were produced by high-purity oxide mixtures melting in platinum or gold crucible at 800 °C in the atmosphere of purified oxygen. The total content of Cu, Mn, Fe, Co and Ni impurities was not more than 0.1–0.5 ppm wt in the initial oxides and glasses. The stability of TZNB glasses to crystallization, characterized by (Tx ? Tg) value more than 150 °C, was demonstrated by DSC measurements at heating rate 10 K/min. In the case of La2O3-containing glasses the thermal effects of both crystallization and fusion of the crystallized phases were not observed. The hydroxyl groups absorption coefficients of pure tellurite glasses at the maximum of the absorption band (λ ~ 3 μm) were in the region of 0.012–0.001 cm?1. The optical absorption losses, measured by the laser calorimetry method at λ = 1.56 and 1.97 μm, did not exceed 100 dB/km.  相似文献   
89.
Russian Journal of Organic Chemistry - 2,2′-(Disulfanediyl)- and 2,2′-[alkanediylbis(sulfanyl)]-bisbenzimidazoles react with aliphatic, aromatic, and heterocyclic α-iodoketones in...  相似文献   
90.
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