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by the National Fire Protection Association (NFPA) [ 7 ]. We investigated the thermokinetic parameters for CHP, DTBP, and TBPB by differential scanning calorimetry (DSC) [ 8 ]. The activation energy ( E a ) for CHP, DTBP, and TBPB at different

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examined using a thermal dynamic calorimeter (differential scanning calorimetry, DSC) and isothermal microcalorimeter (thermal activity monitor III, TAM III) to evaluate basic exothermic decomposition and various thermokinetic parameters. Furthermore

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Abstract  

Information about the kinetics and thermal decomposition of hydrogen peroxide (H2O2) has been required for safety reasons, due to its broad applications in many chemical industries. To determine the inherent hazards during H2O2 manufacturing, transportation, disposal, usage, and so on, this study deliberately selected various H2O2 concentrations and analyzed them by differential scanning calorimetry (DSC). In addition, thermokinetic parameters were not only established for each of these reactions, but also aimed at comprehensive, kinetic models with various tests conducted at different heating rates. To build up a comprehensive kinetic model, various tests were conducted by heating rates of 1, 2, 4, 10C min–1, respectively. According to dynamic DSC tests, the experimental curves show that H2O2 decomposition has one exothermic peak and may start to decompose under 47–81C. The total heat of decomposition is about 192–1079 J g–1. Not only can these results prevent accidents caused by H2O2 during storage and transportation, but also assess its inherent hazards and thereby design procedures for emergency response while runaway reactions occurring.

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are not well understood. Due to the hazardous consequences of decomposition of BTBPC and its extensive use in the industry, we made efforts to understand the runaway reaction phenomena by evaluating the thermokinetic parameters. In this study

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goals of this study were to obtain reliably accurate thermokinetic parameters that can be applied to industrial manufacturing processes and incompatible reactions to avoid a reaction disaster. The thermal activity monitor III (TAM III) [ 8 , 9

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Abstract  

Pooling lauroyl peroxide (LPO) with nitric acid, we used differential scanning calorimetry (DSC) to assess the thermokinetic parameters, such as exothermic onset temperature (T 0), heat of decomposition (ΔH d), frequency factor (A), and the other safety parameters. When LPO was contaminated with nitric acid (HNO3), we found the exploder 1-nitrododecane. Obvious products were sensitive and hazardous chemicals. Concentration reaching 1–12 N HNO3 emitted a large amount of heat. This study combined with curve-fitting method to elucidate its unsafe characteristics and thermally sensitive structure to help prevent runaway reactions, fires and explosions in the process environment. According to the findings and the concept of inherently safer design, LPO runaway reactions could be adequately prevented in the relevant plants.

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Exploring antibiotic resistant mechanism by microcalorimetry II

Determination of thermokinetic parameters of imipenem hydrolysis with metallo-β-lactamase ImiS

Journal of Thermal Analysis and Calorimetry
Authors: Xia Yang, Lei Feng, Kang-Zhen Xu, Hui-Zhou Gao, Chao Jia, Cheng-Cheng Liu, Jian-Min Xiao, Le Zhai, Li-Sheng Zhou, and Ke-Wu Yang

determination of the differential heat of adsorption [ 11 ], and Yang et al. explored inhibition of two cephalosporins on E. coli [ 12 ]. Recently, we reported the determination of thermokinetic parameters of penicillin G hydrolysis catalyzed by MβL L1 from

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Abstract  

Cumene hydroperoxide (CHP) and its derivatives have caused many serious explosions and fires in Taiwan as a consequence of thermal instability, chemical contamination, and even mechanical shock. It has been employed in polymerization for producing phenol and dicumyl peroxide (DCPO). Differential scanning calorimetry (DSC) was used to analyze the thermal hazard of CHP in the presence of sodium hydroxide (NaOH), sulfuric acid (H2SO4), and sodium bisulfite (Na2SO3). Thermokinetic parameters for decomposition, such as exothermic onset temperature (T 0), maximum temperature (T max), and enthalpy (ΔH), were obtained from the thermal curves. Isothermal microcalorimetry (thermal activity monitor, TAM) was employed to investigate the thermal hazards during CHP storage and CHP mixed with NaOH, H2SO4, and Na2SO3 under isothermal conditions in a reactor or container. Tests by TAM indicated that from 70 to 90 °C an autocatalytic reaction was apparent in the thermal curves. According to the results from the TAM test, high performance liquid chromatography (HPLC) was, in turn, adopted to analyze the result of concentration versus time. By the Arrhenius equation, the activation energy (E a) and rate constant (k) were calculated. Depending on the process conditions, NaOH was one of the incompatible chemicals or catalysts for CHP. When CHP is mixed with NaOH, the T 0 is induced earlier and the reactions become more complex than for pure CHP, and the E a is lower than for pure CHP.

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Exploring antibiotic resistant mechanism by microcalorimetry

Determination of thermokinetic parameters of metallo-β-lactamase L1 catalyzing penicillin G hydrolysis

Journal of Thermal Analysis and Calorimetry
Authors: Hui-Zhou Gao, Qi Yang, Xiao-Yan Yan, Zhu-Jun Wang, Ji-Li Feng, Xia Yang, Sheng-Li Gao, Lei Feng, Xu Cheng, Chao Jia, and Ke-Wu Yang

understand the procedure of β-lactam containing antibiotics hydrolysis catalyzed by MβLs, this paper first reports the determination of thermokinetic parameters of penicillin G hydrolysis catalyzed by MβL L1 from Stenotrophomonas maltophilia by

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Abstract  

Multi-walled carbon nanotubes (MWCNTs) have remarkable properties. However, their thermal stability characteristics, which may represent potential hazards during the production or utilization stage, concern unsafe or unknown properties researches. Our aim was to analyze the thermokinetic parameters of different heating rates by differential scanning calorimetry (DSC) and thermogravimetric analyzer (TG), and then to compare thermal decomposition energy parameters under various conditions by well-known kinetic equations. MWCNTs were acidified via nitric acid (HNO3) in various concentrations from 3 to 15 N and were characterized by means of Fourier transform infrared (FTIR) spectrometry. For original and modified MWCNTs, we further identified the thermal degradation characteristics of the functional group by TG-FTIR. Finally, we established an effective and prompt procedure for receiving information on thermal decomposition characteristics and reaction hazard of MWCNTs that could be applied as an inherently safer design during normal or upset operation.

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