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Characterisation of Zinc Oxide and Cadmium Oxide Nanostructures Obtained from the Low Temperature Thermal Decomposition of Inorganic Precursors  [PDF]
K. Kalpanadevi,C. R. Sinduja,R. Manimekalai
ISRN Inorganic Chemistry , 2013, DOI: 10.1155/2013/823040
Abstract: Low temperature syntheses of zinc oxide and cadmium oxide nanoparticles are reported in this paper. The inorganic precursor complexes were prepared and characterised by hydrazine and metal analyses, infrared spectral analysis, and thermal analysis. Using appropriate annealing conditions, zinc oxide and cadmium oxide nanoparticles of average particle sizes around 13?nm and 30?nm were synthesised from the precursors by a simple thermal decomposition route. The synthesised nanoparticles were characterised for their size and structure using X-Ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and scanning electron microscopy (SEM) techniques. 1. Introduction This century has witnessed a tremendous escalation in the field of science and technology, for which the contribution of nanotechnology is much substantial. In the past decade, nanoscale research has opened revolutionary opportunities for a wide number of technological applications. Due to their special optical, magnetic, electrical, and catalytic properties and improved physical properties like mechanical hardness, thermal stability, or chemical passivity [1], metal oxide nanostructures are extensively used as paint pigments, cosmetics, pharmaceuticals, medical diagnostics, catalysts and supports, membranes and filters, batteries and fuel cells, electronics, magnetic and optical devices, flat panel displays, biomaterials, structured materials, and protective coatings [2]. Nanostructures based on zinc oxide and cadmium oxide are particularly interesting because of their n-type conductivity with a wide band gap (3.3?eV and 2.2?eV, resp.) which makes these materials more suitable for modern technologies. ZnO and CdO have promising applications in catalysts [3, 4], gas sensors [5, 6], solar cells [7, 8], paint pigments, and so on. There are several accepted techniques for the preparation of ZnO and CdO nanoparticles such as sol-gel method [9, 10], microemulsion method [11, 12], precipitation method, thermal decomposition [13], hydrothermal method [14, 15], chemical coprecipitation method [16], and thermal evaporation [17]. One of the simplest methods to obtain ZnO and CdO nanoparticles is the thermal decomposition of a suitable precursor. In this context, we have attempted to synthesise ZnO and CdO nanoparticles by the thermal decomposition route from the corresponding inorganic precursor M(cin)2·(N2H4)2 (M = Zn/Cd, cin = cinnamic acid) which involves low temperature, low cost, and low time consumption. 2. Experimental 2.1.
Iron oxide deposits associated with the ectosymbiotic bacteria in the hydrothermal vent shrimp Rimicaris exoculata
L. Corbari,M.-A. Cambon-Bonavita,G. J. Long,F. Grandjean
Biogeosciences Discussions , 2008,
Abstract: The Rimicaris exoculata shrimp is considered a primary consumer that dominates the fauna of most Mid-Atlantic Ridge (MAR) hydrothermal ecosystems. These shrimps harbour in their gill chambers an important ectosymbiotic community of chemoautotrophic bacteria associated with iron oxide deposits. The structure and elemental composition of the minerals associated with these bacteria have been investigated by using X-ray microanalyses, light microscopy, and transmission, environmental scanning and scanning transmission electron microscopy. The nature of the iron oxides in shrimps obtained from the Rainbow vent field at 36°14.0' N, has also been determined by M ssbauer spectroscopy. This multidisciplinary approach has revealed that the three step-levels of mineral crust found in the Rimicaris exoculata shrimps consist of heavy concretions formed by nanoparticles of two-line ferrihydrite intermixed with minor inorganic SiO2, (Ca,Mg)SO4, and (Ca,Mg)3(PO4)2 minerals that may stabilise the ferrihydrite form of iron oxides. Morphological observations on the bacteria have revealed their close interactions with these minerals and, thus, indicate the biogenic origin of the iron oxide deposits. The evolution of the bacterial density in the three mineral crust levels is related to the amount of the iron deposits and it is proposed that the lower crust level is the most likely region for the location of the iron-oxidizing bacteria.
The full nonrigid group theory for trimethylamine
Masood Hamadanian,Ali Reza Ashrafi
International Journal of Mathematics and Mathematical Sciences , 2003, DOI: 10.1155/s0161171203205159
Abstract: The nonrigid molecule group theory (NRG) in which the dynamical symmetry operations are defined as physical operations is a new field in chemistry. Smeyers in a series of papers applied this notion to determine the character table of restricted NRG of some molecules. In this note, a simple method is described by means of which it is possible to calculate character tables for the symmetry group of molecules consisting of a number of methyl groups attached to a rigid framework. We study the full NRG of trimethylamine N(CH3)3 and prove that it is a group of order 1296 with 28 conjugacy classes. The method can be generalized to apply to other nonrigid molecules. The full nonrigid (f-NRG) molecule group theory is seen to be used advantageously to study the internal dynamics of such molecules.
Iron oxide deposits associated with the ectosymbiotic bacteria in the hydrothermal vent shrimp Rimicaris exoculata
L. Corbari, M.-A. Cambon-Bonavita, G. J. Long, F. Grandjean, M. Zbinden, F. Gaill,P. Compère
Biogeosciences (BG) & Discussions (BGD) , 2008,
Abstract: The Rimicaris exoculata shrimp is considered as a primary consumer that dominates the fauna of most Mid-Atlantic Ridge (MAR) hydrothermal ecosystems. These shrimps harbour in their gill chambers an important ectosymbiotic community of chemoautotrophic bacteria associated with iron oxide deposits. The structure and elemental composition of the mineral concretions associated with these bacteria have been investigated by using LM, ESEM, TEM STEM and EDX microanalyses. The nature of the iron oxides in shrimps obtained from the Rainbow vent field has also been determined by M ssbauer spectroscopy. This multidisciplinary approach has revealed that the three layers of mineral crust in the Rimicaris exoculata shrimps consist of large concretions formed by aggregated nanoparticles of two-line ferrihydrite and include other minor elements as Si, Ca, Mg, S and P, probably present as silicates cations, sulphates or phosphates respectively that may contribute to stabilise the ferrihydrite form of iron oxides. TEM-observations on the bacteria have revealed their close interactions with these minerals. Abiotic and biotic precipitation could occur within the gill chamber of Rimicaris exoculata, suggesting the biologically-mediated formation of the iron oxide deposits. The difference of the bacterial density in the three-mineral crust layers could be correlated to the importance of the iron oxide concretions and suggest that the first mineral particles precipitates on the lower layer which could be considered as the most likely location of iron-oxidizing bacteria.
Trimethylamine Formation in Fillets of Yellowfin Tuna as an Index of Freshness: Variation With Storage Time and Temperature  [cached]
G. Esparaz,G. J. B. Cajipe
Science Diliman , 1983,
Abstract: Trimethylamine in fillets of yellowfin tuna was determined qualitatively by paper chromatography and quantitatively by monitoring the absorbance of the trimethylamine picrate salt at 410 mm. The results show that the concentration of trimethylamine increase with storage time and temperature.
Decomposition of hexachlorobenzene over Al2O3 supported metal oxide catalysts

ZHANG Lifei,ZHENG Minghui,ZHANG Bing,LIU Wenbin,GAO Lirong,BA Te,REN Zhiyuan,SU Guijin,

环境科学学报(英文版) , 2008,
Abstract: Decomposition of hexachlorobenzene (HCB) was investigated over several metal oxides (i.e., MgO, CaO, BaO, La2O3,CeO2, MnO2, Fe2O3 and Co3O4) supported on Al2O3, which was achieved in closed system at a temperature of 300℃. Catalysts were prepared by incipient wetness impregnation with different metal oxides loading and impregnating solvents. The decomposition efficiency of different catalysts for this reaction depends on the nature of the metal oxide used, and Al2O3 supported La2O3 was found to be the most active one. Pentachlorobenzene (PeCB), and all tetrachlorobenzene (TeCB), trichlorobenzene (TrCB), and dichlorobenzene (DCB) isomers were detected after the decomposition reaction, indicating that the decomposition was mainly a dechlorination process. The detection of all lower chlorinated beazenes suggested the complexity of decomposition and the presence of more than one dechlodnation pathway.
A Comparative Investigation of Lead Sulfate and Lead Oxide Sulfate Study of Morphology and Thermal Decomposition  [PDF]
S. A. A. Sajadi
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.22024
Abstract: The compound lead oxide sulfate PbSO4.PbO was prepared in our laboratory. The Thermal behavior of PbSO4 was studied using techniques of Thermogravimetry under air atmosphere from 25 to 1200°C. The identity of both compounds was confirmed by XRD technique. Results obtained using both techniques support same decomposition stages for this compound. The electron microscopic investigations are made by SEM and TEM. The compound is characterized by XRD and the purity was determined by analytical Methods. Also a series of thermogravimetric analysis is made and the ideal condition is determined to convert this compound to pure lead oxide.
Development of QCM Trimethylamine Sensor Based on Water Soluble Polyaniline  [PDF]
Guang Li,Junbao Zheng,Xingfa Ma,Yu Sun,Jun Fu,Gang Wu
Sensors , 2007, DOI: 10.3390/s7102378
Abstract: A rapid, sensitive, low-cost device to detect trimethylamine was presented in thispaper. The preparation of water soluble polyaniline was firstly studied. Then the polyanilinewas characterized via Fourier transform infrared spectroscopy (FTIR), UV-visiblespectroscopy and scanning electron microscopy (SEM). Based on the water solublepolyaniline film, a quartz crystal microbalance (QCM) sensor for trimethylamine detectionwas fabricated and its characteristics were examined. The sensor consisted of one quartzcrystal oscillator coated with the polyaniline film for sensing and the other one forreference. Pretreated with trimethylamine, the QCM sensor had an excellent linearsensitivity to trimethylamine. Easily recovered by N2 purgation, the response of the sensorexhibited a good repeatability. Responses of the sensor to trimethylamine, ethanol and ethylacetate were compared, and the results showed that the response was related to the polarityof the analyte vapor. Experimental result also showed that the sensitivity of the sensor wasrelatively stable within one month. The simple and feasible method to prepare and coat thepolyaniline sensing film makes it promising for mass production.
尿素/氧化三甲胺混合溶剂影响单壁碳纳米管内部水合性质的分子动力学模拟
Molecular Dynamic Simulations of the Effects of Trimethylamine-N-oxide/Urea Mixture on the Hydration of Single-Walled Carbon Nanotube Interiors
 [PDF]

杨立江,高毅勤,()
- , 2016, DOI: 10.3866/PKU.WHXB201512161
Abstract: 尿素是早已被人们认识的蛋白质变性剂,而氧化三甲胺则是最常用的蛋白质结构保护剂。虽然多年来被广泛应用在生物实验中,但是它们是如何在蛋白质结构形成中起作用,特别是氧化三甲胺是如何在高浓度尿素环境中起到抑制尿素蛋白变性作用的分子机制,至今仍然没有得到圆满解答。本文以单壁碳纳米管为模型疏水体系,采用分子动力学模拟研究尿素/氧化三甲胺混合溶液中纳米管内部水合性质,结果表明氧化三甲胺更易与水分子和尿素分子形成较强相互作用从而稳定了水溶液结构,这一结果亦表明了氧化三甲胺可以通过间接机制抵消尿素分子对于碳纳米管内部水合性质的影响。
Urea is known for protein denaturation.The counteracting effect of trimethylamine-N-oxide (TMAO) against urea-induced protein denaturation is also well established.However, what is largely unknown is the mechanism TMAO counteracts urea.In this article, the hydration of the interior of a simple single-walled carbon nanotube in a urea/TMAO mixture is studied as a model system for hydrophobic hydration using molecular dynamic simulations.The results show that TMAO counteracts the hydration effect of urea to the nanotube interior through strong interactions among TMAO, water, and urea.The strong interactions of TMAO and water stabilize the water structure, which counteracts the effects of urea indirectly
Modelling the behaviour of microbulk Micromegas in Xenon/trimethylamine gas  [PDF]
E. Ruiz-Choliz,D. Gonzalez-Diaz,A. Diago,J. Castel,T. Dafni,D. C. Herrera,F. J. Iguaz,I. G. Irastorza,G. Luzon,H. Mirallas, O. Sahin,R. Veenhof
Physics , 2015, DOI: 10.1016/j.nima.2015.07.062
Abstract: We model the response of a state of the art micro-hole single-stage charge amplication device (`microbulk' Micromegas) in a gaseous atmosphere consisting of Xenon/trimethylamine at various concentrations and pressures. The amplifying structure, made with photo-lithographic techniques similar to those followed in the fabrication of gas electron multipliers (GEMs), consisted of a 100 um-side equilateral-triangle pattern with 50 um-diameter holes placed at its vertexes. Once the primary electrons are guided into the holes by virtue of an optimized field configuration, avalanches develop along the 50 um-height channels etched out of the original doubly copper-clad polyimide foil. In order to properly account for the strong field gradients at the holes' entrance as well as for the fluctuations of the avalanche process (that ultimately determine the achievable energy resolution), we abandoned the hydrodynamic framework, resorting to a purely microscopic description of the electron trajectories as obtained from elementary cross-sections. We show that achieving a satisfactory description needs additional assumptions about atom-molecule (Penning) transfer reactions and charge recombination to be made.
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