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Studies on the Internal Ballistics of Composite Solid Rocket Propellants Incorporating Nano-Structured Catalysts

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Advances in Aerospace Science and Technology 2017年第4期2卷 48-72页

作者： Mukesh R. Sivasubramaniyam R. Elangovan R. R. Abhinaya Sree R. Harish R. Rajashree D. Satish Kumar Kanhar Department of Aeronautical Engineering A.C.S College of Engineering Bangalore India Department of Mechanical Engineering A.C.S College of Engineering Bangalore India

This paper deals with the analysis of burn rate using various catalysts of Iron Oxide and determining which gives the higher burn rate with low pressure variation. The Ammonium Perchlorate (AP) was obtained and ground into fine powder with the particle size ranging from 63 to 125 μm. The propellant strands were prepared with proportions by mixing AP with the binder (hydroxyl Terminated Polybutadiene), the catalyst (Iron Oxide), curing agent (Isophorone diisocyanate) and the plasticizer (Dioctyladipate). The prepared propellant mixture was cured at around 63 deg C to get various propellant strands. The first strand was prepared with the absence of a catalyst to set an initial base of comparison with other Iron Oxide catalysts, namely, Flower Shaped, Micro and Nano, based on the size of the particles. The combustion process was carried out in a strand burner, which was in turn connected to a data acquisition system. The obtained output was analysed in the form of graphs. The burn rate was achieved by calculating the slope of the graph i.e . by calculating the difference between the highest and the lowest peak of the graph and dividing the total time by the answer. The experiment was repeated with the different catalyst types, as mentioned above, at different pressures. It was observed that the Nano shaped Iron Oxide exhibits better burning characteristics when compared to the rest with the pressure index of 0.792. In this paper, the various experiments carried out along with their procedures are explained in detail. The results obtained and the techniques used are also elaborately described in this paper.

关键词： Ammonium Perchlorate Dioctyladipate hydroxyl Terminated

Treatment of M.aeruginosa contaminated water by plasma discharge

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Science Foundation in China 2015年第1期23卷 20-20页

Recently,Prof.Huang Qing’s group at the Institute of Technical Biology&.Agriculture Engineering(Hefei Institutes of Physical Science,Chinese Academy of Sciences)have utilized non-thermal plasma discharge to treat was... 详细信息

关键词： contaminated utilized Hefei dissolved hydroxyl untreated cytometry challenge concerned collide

Electrochemical analysis mechanism on different crystal phases of nano-Fe_2O_3 revealed by EXAFS

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Science Foundation in China 2016年第2期24卷 16-16页

With the support by the National Natural Science Foundation of China,the National Basic Research Program of China,and the National High Technology Research and Development Program of China,the research group led by Prof.Huang Xingjiu(黄行九)at the Institute of Intelligent Machines,Chinese Acade-myof Sciences(CAS)cooperated with Prof.

关键词：行九 Figure adsorbed pursuit crystalline octahedral sorption hydroxyl complexes corrected

Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton Process

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American Journal of Analytical Chemistry 2014年第8期5卷 500-517页

作者： Sondos Dbira Ahmed Bedoui Nasr Bensalah Department of Chemistry and Earth Sciences College of Arts and Sciences Qatar University Doha Qatar Department of Chemistry Faculty of Sciences of Gabes University of Gabes Gabes Tunisia

In this work, the degradation of 2-chloro-4,6-diamino-1,3,5-triazine in aqueous solutions by photo-Fenton process has been investigated. The preliminary results have shown that the degradation of 2-chloro-4,6-diamino-1,3,5-triazine by photo-Fenton process is more rapid and more effective than Fenton and UV/H2O2 processes. The effects of certain experimental parameters on kinetics and efficiency of the degradation of 2-chloro-4,6,-diamino-1,3,5-triazine by photo-Fenton process, have been evaluated. Under optimal conditions, photo-Fenton process achieved more than 90% of chloride release and about 30% of nitrate formation. The results of total organic carbon (TOC) and total Kjeldahl nitrogen (TKN) analyses have shown that no carbon dioxide and ammonia are formed during photo-Fenton treatment of aqueous solutions containing 40 mg/L triazine. These results indicate that only substituent groups of triazine ring are released;however, nitrogen atoms of triazine ring remain unaffected. A simple mechanism of degradation of 2-chloro-4,6-diamino-1,3,5-triazine has been proposed. The degradation starts by a rapid release of chlorine atoms as chloride ions to form 2-hydroxy-4,6-diamino-1,3,5-triazine. The amino groups of 2-hydroxy-4,6-diamino-1,3,5-triazine undergo are oxidized into nitro groups by hydroxyl radicals to form 2-hydroxy-4,6-dinitro-1,3,5-triazine which undergoes a slow release of nitro groups and their substitution with hydroxyl groups to form cyanuric acid and nitrate ions. The degradation of cyanuric acid by photo-Fenton process has also been investigated. The results of TOC and TKN analyzes show that no carbon dioxide is formed during the treatment.

关键词： Photo-Fenton Process hydroxyl Radicals s-Triazine Herbicides Degradation Cyanuric Acid

Removal of 17β-Estradiol by Electro-Fenton Process

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Materials Sciences and Applications 2012年第12期3卷 880-886页

作者： I. Naimi N. Bellakhal Department of Chemistry and Biology National Institute of Applied Sciences and Technology Tunis Tunisia

The Electrochemical advanced oxidation method “Electro-Fenton” has been applied to remove 17β-estradiol (17β)- estra-1,3,5(10)-triéne-3,17-diol) in aqueous-acetonitrile mixture. This endocrine disrupting is a steroid hormone, releases from humans, animals and residual pharmaceuticals into the environmental water and usually causes suspected undesirable effects in aquatic organisms. The degradation of this organic compound by Electro-Fenton process was showed using a carbon felt cathode and platinum anode. The evolution of the concentration during treatment was followed up by high performance liquid chromatography (HPLC). The influence of operating conditions on the degradation of 17β-estradiol by Electro-Fenton step, such as initial concentration and catalyst concentration, has been investi- gated and discussed. We showed that the degradation reaction obeyed apparent first-order reaction kinetics, with absolute rate constant determined as 5.12 × 109 M–1 s–1 by competitive kinetics method taking Benzoic Acid as reference compound. The results confirm the efficiency of the Electro-Fenton process to degrade organic pollutant in aqueous-acetonitrile mixture.

关键词： 17β-Estradiol Endocrine Disrupting Chemicals Electro-Fenton hydroxyl Radicals Degradation

Carcinogenesis of asbestos switched on by inducing cross-linkage between DNA complementary pair bases

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Chinese Science Bulletin 2002年第13期47卷 1086-1091页

作者： DAI Qianhuan CHEN Sha LI Yingxia Center of Environmental Science Peking UniversityBeijing 100871China Center for Chemistry and Bioengineering of Cancer Beijing Polytechnic UniversityBeijing 100022China

Since the beginning of the 1980s, Dai Qianhuan predicted based upon his di-region theory that the carcino-genesis switched on by the so-called physical carcinogenic factors including radiation, asbestos and foreign matter implantation, is just initiated through the cross-linking between DNA complementary pair bases induced by them. In this note, it was evidenced with the DNA filter elution method that the oxygenase activated by asbestos induces the cross-linking between DNA inter-strands and DNA-protein with dosage correlation, in which over 80% of DNA inter-strand cross-link ratio account for the total cross-link ratio. Obviously, both of the cross-linkages are just induced by hydroxyl free radical, HO·, because the ferrous ion increased the cross-link ratios up to several times through Fenton reaction and vitamin C inhibited the cross-link ratios with factors of 8-9 by destroying the hydroxyl radical. Non-carcinogen but with lower free radical formation energy, pyrene, by culturing with asbestos

关键词： asbestos mechanism of carcinogenesis di-region theory hydroxyl free radical DNA interstrand cross-link Fenton reaction AM1 molecular orbital calculation.

Effect of the Pre-Treatment Severity on the Antioxidant Properties of Ethanol Organosolv Miscanthus x giganteus Lignin

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Natural Resources 2012年第2期3卷 29-34页

作者： Roland El Hage Dominique Perrin Nicolas Brosse Centre des Matériaux de Grande Diffusion (CMGD) Ecole des Mines d’Alès France Laboratoire d’Etude et de Recherche sur le MAteriau Bois Faculté des Sciences et Techniques Nancy-Université Boulevard des Aiguillettes France Laboratoire d’Etude et de Recherche sur le MAteriau Bois Faculté des Sciences et Techniques Nancy-Université Boulevard des Aiguillettes France.

The effect of the severity of an organosolv treatment of Miscanthus x giganteus on antioxidant capacity of the obtained lignin was studied. Four organosolv lignins extracted with different severity conditions were chosen and tested. Results obtained using the methyl linoleate method have shown a correlation between oxygen uptake index and the combined severity. It was found that lignin extracted at higher severity pre-treatment and with a higher phenolic hydroxyl content, lower aliphatic hydroxyl content, molecular weight and polydispersity has the highest antioxidant capacity.

关键词： Miscanthus x giganteus Organosolv Lignin Antioxidant Combined Severity Molecular Weight Phenolic and Aliphatic hydroxyl

STUDIES ON KINETICS OF DESORPTION OF CO_2 FROM HOT CARBONATED POTASH SOLUTION WITH DETA (DIETHYLENETRIAMINE) AS A CATALYST

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Chinese Journal of Chemical Engineering 1989年第1期 59-72页

作者：李道棠涂晋林施亚钧 Shanghai Jiao Tong University Shanghai East China Institute of Chemical Technology Shanghai

Under atmosphe（）e press（）ne, rates of deseption of CO（） from unmod（）ed carbonated potash solutior （27 wt%）and modified carbonated potash solution（27 wt%） containing DETA as a catalyst, have been measured in a laboratory stirred reactor. Experiments were carried out with concentrations of DETA from 0—40g/L and temperatures from 90—104℃The results, show that the desorption of CO2 from hot carbonated solutions with and without the addition of DETA, may be considered a pseudo-first order reversible reaction, and that the desorption of CO2 from carbonated potash solution calalysed by DEIA is in agreement with the mechanism of simultancous reactions of CO2 with amine molecules and with hydroxyl ions in solution. Mathematical models for desorptions rate cocflicient have been cstablished, and optimum concentration of DETA is proposed.

关键词： DETA desorption hydroxyl reversible stirring volatile removed boiling maintained deviation

EFFECT OF WATER ON THE OXIDATION OF METHANOL OVER ELECTROLYTIC SILVER

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分子催化 1990年第S1期4卷 85-89页

作者： Zhou Qinwei and Deng Jingfa(Chemistry Department, Fudan University, Shanghai, China)

The mechanism of methanol adsorption induced by oxygen and the effect of water on the methanol oxidation on electrolytic silver have been studied by ultra-high vacuum temperature programmed reaction spectroscopy(TPRS), transient response method and isotopic exchange experiment. It has been found that oxygen adsorbed on silver can greatly promote methanol adsorption and can also react with methanol to produce water. Experimental results show that oxygen in the water comes from the adsorbed oxygen and hydrogen from the methyl and the hydroxyl in methanol. It has also been found that there exists competitive adsorption between water and oxygen on silver and water can increase the selectivity of methanol oxidation to formaldehyde. This result is consistent with the catalytic activities.

关键词： methanol formaldehyde silver competitive adsorbed selectivity electrolytic suddenly programmed hydroxyl