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Advances Treatment Technologies in Chemical Industry Wastewater
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作者 Mengyi Xie Tao Yu Zhang Meng 《Expert Review of Chinese Chemical》 2024年第1期27-33,共7页
The main treatment methods of chemical wastewater were reviewed.Physical,chemical,and biochemical treatment technologies effective for removing those pollutants were presented with their applicability,effectiveness an... The main treatment methods of chemical wastewater were reviewed.Physical,chemical,and biochemical treatment technologies effective for removing those pollutants were presented with their applicability,effectiveness and advantages.The problems facing the wastewater treatment in the petroleum chemical industry and coal chemical industry were introduced.In the end,the new progress and trend of the processes were overviewed. 展开更多
关键词 chemical wastewater treatment technique research progress
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Deterioration of equivalent thermal conductivity of granite subjected to heating-cooling treatment 被引量:1
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作者 Mohua Bu Peng Zhang +3 位作者 Pingye Guo Jiamin Wang Zhaolong Luan Xin Jin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4229-4246,共18页
Understanding the thermal conductivity of granite is critical for many geological and deep engineering applications.The heated granite was subjected to air-,water-,and liquid nitrogen(LN2-)coolings in this context.The... Understanding the thermal conductivity of granite is critical for many geological and deep engineering applications.The heated granite was subjected to air-,water-,and liquid nitrogen(LN2-)coolings in this context.The transient hot-wire technique was used to determine the equivalent thermal conductivity(ETC)of the granite before and after treatment.The deterioration mechanism of ETC is analyzed from the meso-perspective.Finally,the numerical model is used to quantitatively study the impact of cooling rate on the microcrack propagation and heat conduction characteristics of granite.The results show that the ETC of granite is not only related to the heating temperature,but also affected by the cooling rate.The ETC of granite decreases nonlinearly with increasing heating temperature.A faster cooling rate causes a greater decrease in ETC at the same heating temperature.The higher the heating temperature,the stronger the influence of cooling rate on ETC.The main explanation for the decrease in ETC of granite is the increase in porosity and microcrack density produced by the formation and propagation of pore structure and microcracks during heating and cooling.Further analysis displays that the damage of granite at the heating stage is induced by the difference in thermal expansion and elastic properties of mineral particles.At the cooling stage,the faster cooling rate causes a higher temperature gradient,which in turn produces greater thermal stress.As a result,it not only causes new cracks in the granite,but also aggravates the damage at the heating stage,which induces a further decrease in the heat conduction performance of granite,and this scenario is more obvious at higher temperatures. 展开更多
关键词 Equivalent thermal conductivity(ETC) GRANITE Heating-cooling treatment Pore structure MICROCRACK Grain-based model
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Recent progresses in thermal treatment of β-Ga_(2)O_(3) single crystals and devices
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作者 Yuchao Yan Zhu Jin +1 位作者 Hui Zhang Deren Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1659-1677,共19页
In recent years,ultra-wide bandgap β-Ga_(2)O_(3) has emerged as a fascinating semiconductor material due to its great potential in power and photoelectric devices.In semiconductor industrial,thermal treatment has bee... In recent years,ultra-wide bandgap β-Ga_(2)O_(3) has emerged as a fascinating semiconductor material due to its great potential in power and photoelectric devices.In semiconductor industrial,thermal treatment has been widely utilized as a convenient and effective approach for substrate property modulation and device fabrication.Thus,a thorough summary of β-Ga_(2)O_(3) substrates and devices behaviors after high-temperature treatment should be significant.In this review,we present the recent advances in modulating properties of β-Ga_(2)O_(3) substrates by thermal treatment,which include three major applications:(ⅰ)tuning surface electrical properties,(ⅱ)modifying surface morphology,and(ⅲ)oxidating films.Meanwhile,regulating electrical contacts and handling with radiation damage and ion implantation have also been discussed in device fabrication.In each category,universal annealing conditions were speculated to figure out the corresponding problems,and some unsolved questions were proposed clearly.This review could construct a systematic thermal treatment strategy for various purposes and applications of β-Ga_(2)O_(3). 展开更多
关键词 β-gallium oxide thermal treatment SUBSTRATES DEVICES
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Effect of Processing and Cultivar on Thermo-Chemical Properties of Australian-Grown Hemp Hurd(Cannabis sativa L.)
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作者 Johannes Fehrmann Benoit Belleville +2 位作者 Barbara Ozarska Maya Ismayati Wahyu Dwianto 《Journal of Renewable Materials》 EI CAS 2024年第8期1475-1493,共19页
This study explored the thermo-chemical properties of industrial hemp hurd with different provenances,maturity stages,and retting protocols.The findings were then compared to hemp hurd used in the fabrication of citri... This study explored the thermo-chemical properties of industrial hemp hurd with different provenances,maturity stages,and retting protocols.The findings were then compared to hemp hurd used in the fabrication of citric acid-bonded ultra-low-density hemp hurd particleboard.Pyrolysis-gas chromatography-mass spectrometry(Py-GC/MS),Fourier-transform infrared spectroscopy(FTIR),and thermogravimetric analysis(TGA)were employed to document the variability of the hurd and comprehend the potential impact on biobased composite applications.The choice of cultivar,maturity stage,and processing modality significantly influenced the chemical composition,presence of functional groups,and thermal stability of the hurd.Py-GC/MS revealed substantial variations in the lignin-to-carbohydrate(L/C)ratio,along with the absence of fatty acids in certain cultivars.While FTIR signals confirmed consistent functional groups,differences in peak intensities were indicative of carbohydrate variations associated with maturity and retting duration,impacting the availability of hydroxyl groups for,i.e.,interparticle bonding in citric acid-based bio-composites.Furthermore,it was observed that shorter retting durations initially enhanced the thermal resistance,but prolonged retting led to accelerated degradation,significantly reducing the hurd’s residual mass.The findings indicated notable differences among the samples,emphasizing the importance of investigating variables such as provenance/cultivar,maturity,and processing modality.This assessment is essential to ensure effective agronomic practices that align the raw material characteristics with the specific requirements of intended applications,such as the fabrication of biobased hemp hurd composites. 展开更多
关键词 Hemp hurd material characterization chemical analysis thermal analysis
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Progress of Electrocatalytic Technology in Treating Organic Chemical Wastewater
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作者 Lun Deng Hemei Wang 《Expert Review of Chinese Chemical》 2024年第1期9-14,共6页
In recent years,extensive research has been conducted on the preparation of high catalytic performance electrodes and the development of electrocatalytic water treatment processes.This article introduces the basic pri... In recent years,extensive research has been conducted on the preparation of high catalytic performance electrodes and the development of electrocatalytic water treatment processes.This article introduces the basic principles of electrochemical water treatment,the preparation of electrode materials,and the research progress of electrocatalytic technology for degrading organic chemical wastewater.It analyzes the problems faced by electrocatalytic degradation of organic chemical wastewater and looks forward to the development trend of electrocatalytic technology in the field of organic chemical wastewater treatment. 展开更多
关键词 ELECTROCATALYSIS electrode preparation organic chemical wastewater water treatment
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Effects of Chemical Treatments on Thermal Expansion Properties of Cordierite Ceramics 被引量:3
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作者 白佳海 郭露村 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第3期100-102,共3页
Cordierite honeycomb ceramics was treated with 1.5 M HNO3 , followed with 1.5 M NaOH at 93 ℃. The combination of acid treatment with alkali treatment significantly diminished the rebounding of coefficient of thermal ... Cordierite honeycomb ceramics was treated with 1.5 M HNO3 , followed with 1.5 M NaOH at 93 ℃. The combination of acid treatment with alkali treatment significantly diminished the rebounding of coefficient of thermal expansion (CTE) caused by heat treatment, a phenomenon observed in samples treated solely with acid. Inductively coupled plasma (ICP) analysis results reveal that the alkali treatment preferentially dissolved "free" SiO2 left in the acid-treated samples, which is considered to be a key factor responsible for the CTE rebounding. 展开更多
关键词 CORDIERITE alkali treatment coefficient of thermal expansion (CTE)
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Hydrogeochemical Study of Northern Algeria Hot Springs for Thermal Treatments
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作者 Mébrouk Benziada 《Journal of Chemistry and Chemical Engineering》 2019年第1期40-47,共8页
Thermal medicine offers an original approach to health that is not only based on treating symptoms. The major advantage of thermal medicine is based on the overall support of the disease, providing prevention, allevia... Thermal medicine offers an original approach to health that is not only based on treating symptoms. The major advantage of thermal medicine is based on the overall support of the disease, providing prevention, alleviation and treatment of many diseases (rheumatism, bronchitis, skin diseases, etc). In order to get the best possible results by thermal treatments, regular and accurate analysis of the thermal waters of the hot springs is often necessary. This article has a scientific objective for the development of fundamental knowledge needed to better control the hydrogeochemical hot springs in northern Algeria. This study will be addressed by conventional chemical analysis of major chemical elements found at water points (hot springs) in northern Algeria. The results are obtained in the form of semi-logarithmic graphs (Schoeller and Berkallof) and rhombic (Piper). 展开更多
关键词 Hydrogeochemical HOT SPRING NORTHERN Algeria thermal MEDICINE water MINERALIZATION chemical analysis
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Influence of Thermophoresis and Brownian Motion of Nanoparticles on Radiative Chemically-Reacting MHD Hiemenz Flow over a Nonlinear Stretching Sheet with Heat Generation 被引量:1
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作者 S.Mohammed Ibrahim P.Vijaya Kumar G.Lorenzini 《Fluid Dynamics & Materials Processing》 EI 2023年第4期855-868,共14页
In this study,a radiative MHD stagnation point flow over a nonlinear stretching sheet incorporating thermophoresis and Brownian motion is considered.Using a similarity method to reshape the underlying Partial differen... In this study,a radiative MHD stagnation point flow over a nonlinear stretching sheet incorporating thermophoresis and Brownian motion is considered.Using a similarity method to reshape the underlying Partial differential equations into a set of ordinary differential equations(ODEs),the implications of heat generation,and chemical reaction on the flow field are described in detail.Moreover a Homotopy analysis method(HAM)is used to interpret the related mechanisms.It is found that an increase in the magnetic and velocity exponent parameters can damp the fluid velocity,while thermophoresis and Brownian motion promote specific thermal effects.The results also demonstrate that as the Brownian motion parameter is increased,the concentration values become smaller. 展开更多
关键词 Hiemenz flow MHD thermal radiation nonlinear stretching chemical reaction HAM
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Chemical stability, thermal behavior, and shelf life assessment of extruded modified double-base propellants 被引量:4
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作者 Sherif Elbasuney Ahmed Fahd +2 位作者 Hosam E.Mostafa Sherif F.Mostafa Ramy Sadek 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第1期70-76,共7页
Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammo... Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammonium perchlorate/Aluminum), and energetic nitramines(HMX) offered enhanced thrust as well as combustion characteristics. This study is devoted to evaluate the impact of such energetic additives on thermal behavior, chemical stability, and shelf life. Extruded MDB formulations were manufactured by extrusion process. Artificial aging at 80℃ for 28 days was conducted. Shelf life assessment was performed using Van't Hoff's equation. Quantification of evolved NOxgases with aging time was performed using quantitative stability tests. MDB formulation based on HMX demonstrated extended service life of 16 years compared with(AP/Al)-MDB which demonstrated 9 years. This finding was ascribed to the reactivity of AP with nitroglycerin with the formation of perchloric acid. Thermal behavior of aged MDB, exhibited an increase in heat released with time; this was ascribed to the autocatalytic thermal degradation during artificial aging. The increase in released heat by 31% was found to be equivalent to evolved NOx gases of 6.2 cm^3/5 g and 2.5 cm^3/1 g for Bergmann-Junk test, and Vacuum stability test respectively. This manuscript shaded the light on a novel approach to quantify evolved NOx gases to heat released with aging time. MDB based on HMX offered balanced ballistic performance,chemical stability, and service life. 展开更多
关键词 Double-base chemical stability thermal behavior Artificial AGING SHELF life ASSESSMENT
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Petro-chemical wastewater treatment by biological process 被引量:6
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作者 Guan, Wei-Sheng Lei, Zi-Xue Zhu, Jun-Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第2期95-99,共5页
In order to study the feasibility of treating petro chemical wastewater by the combination of anaerobic and aerobic biological process, a research of treating wastewater in UASB reactor and aeration basin has been co... In order to study the feasibility of treating petro chemical wastewater by the combination of anaerobic and aerobic biological process, a research of treating wastewater in UASB reactor and aeration basin has been conducted. The test results shows that under moderate temperature, with 5\^2 kgCOD/(m\+3·d) volumetric load of COD Cr in the UASB reactor and 24h of HRT, 85% removal rate of BOD 5 and 83% of COD \{Cr\} and 1\^34 m\+3/(m\+3·d) volumetric gas production rate can be obtained respectively. The aerobic bio degradability can be increased by 20%—30% after the petro chemical wastewater has been treated by anaerobic process. As Ns=0\^45 kgCOD/(kgMLSS·d), HRT=4h in the aeration tank, 94% removal rate of BOD 5, 93% of COD \{Cr\}, 98\^8% total removal rate of COD \{Cr\} and 99% removal rate of BOD 5 can be reached. 展开更多
关键词 anaerobic aerobic process petro chemical wastewater wastewater treatment CLC number: X703 Document code: A
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Heat strain in chemical protective clothing in hot-humid environment:Effects of clothing thermal properties 被引量:6
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作者 ZHANG Chuan-kun CHEN Ying +3 位作者 LIANG Guo-jie WANG Xin-bo ZHENG Xiao-hui DING Song-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第12期3654-3665,共12页
Heat strain experienced by individuals wearing chemical protective clothing(CPC)is severe and dangerous especially in hot-humid environment.The development of material science and interdisciplinary studies including e... Heat strain experienced by individuals wearing chemical protective clothing(CPC)is severe and dangerous especially in hot-humid environment.The development of material science and interdisciplinary studies including ergonomics,physiology and heat transfer is urgently required for the reduction of heat strain.The aim of this paper was to study the relationship among clothing thermal properties,physiological responses and environmental conditions.Three kinds of CPC were selected.Eight participants wore CPC and walked(4 km/h,two slopes with 5%and 10%)on a treadmill in an environment with(35±0.5)℃ and RH of(60±5)%.Core temperature,mean skin temperature,heart rate,heat storage and tolerance time were recorded and analyzed.Physiological responses were significantly affected by the clothing thermal properties and activity intensity in hot-humid environment.The obtained results can help further development of heat strain model.New materials with lower evaporative resistance and less weight are necessary to release the heat strain in hot-humid environments. 展开更多
关键词 heat strain chemical protective clothing thermal insulation evaporative resistance hot-humid environment
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Numerical investigation of variable viscosities and thermal stratification effects on MHD mixed convective heat and mass transfer past a porous wedge in the presence of a chemical reaction 被引量:2
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作者 I. Muhaimin R. Kandasamy Azme B. Khamis 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1353-1364,共12页
An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid... An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid past a porous wedge in the presence of a chemical reaction. The wall of the wedge is embedded in a uniform nonDarcian porous medium in order to allow for possible fluid wall suction or injection. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically with finite difference methods. Numerical calculations up to the thirdorder level of truncation are carried out for different values of dimensionless parameters. The results are presented graphically, and show that the flow field and other quantities of physical interest are significantly influenced by these parameters. The results are compared with those available in literature, and show excellent agreement. 展开更多
关键词 variable viscosity chemical reaction non-Darcy flow mixed convection thermal stratification magnetic effect
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Effect of a synthesized anionic fluorinated surfactant on wettability alteration for chemical treatment of near-wellbore zone in carbonate gas condensate reservoirs 被引量:3
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作者 Iman Nowrouzi Amir H.Mohammadi Abbas Khaksar Manshad 《Petroleum Science》 SCIE CAS CSCD 2020年第6期1655-1668,共14页
The pressure drop during production in the near-wellbore zone of gas condensate reservoirs causes condensate formation in this area.Condensate blockage in this area causes an additional pressure drop that weakens the ... The pressure drop during production in the near-wellbore zone of gas condensate reservoirs causes condensate formation in this area.Condensate blockage in this area causes an additional pressure drop that weakens the effective parameters of production,such as permeability.Reservoir rock wettability alteration to gas-wet through chemical treatment is one of the solutions to produce these condensates and eliminate condensate blockage in the area.In this study,an anionic fluorinated surfactant was synthesized and used for chemical treatment and carbonate rock wettability alteration.The synthesized surfactant was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.Then,using surface tension tests,its critical micelle concentration(CMC)was determined.Contact angle experiments on chemically treated sections with surfactant solutions and spontaneous imbibition were performed to investigate the wettability alteration.Surfactant adsorption on porous media was calculated using flooding.Finally,the surfactant foamability was investigated using a Ross-Miles foam generator.According to the results,the synthesized surfactant has suitable thermal stability for use in gas condensate reservoirs.A CMC of 3500 ppm was obtained for the surfactant based on the surface tension experiments.Contact angle experiments show the ability of the surfactant to chemical treatment and wettability alteration of carbonate rocks to gas-wet so that at the constant concentration of CMC and at 373 K,the contact angles at treatment times of 30,60,120 and 240 min were obtained 87.94°,93.50°,99.79°and 106.03°,respectively.However,this ability varies at different surfactant concentrations and temperatures.The foamability test also shows the suitable stability of the foam generated by the surfactant,and a foam half-life time of 13 min was obtained for the surfactant at CMC. 展开更多
关键词 Condensate blockage chemical treatment Wettability alteration Gas-wetting Fluorinated surfactant Surface tension
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Ablation properties of C/C composites with various needled preforms prepared by isothermal chemical vapor infiltration 被引量:5
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作者 汤素芳 王道岭 +2 位作者 邓景屹 刘文川 杨柯 《Journal of Central South University of Technology》 EI 2007年第1期13-18,共6页
The ablation properties of C/C composites with four different needled preforms prepared by isothermal chemical vapor infiltration (ICVI), which are super-thin mat lay-up, 0°/90° weftless fabric lay-up, 0&#... The ablation properties of C/C composites with four different needled preforms prepared by isothermal chemical vapor infiltration (ICVI), which are super-thin mat lay-up, 0°/90° weftless fabric lay-up, 0°/45° weftless fabric lay-up and 0°/45° twill fabric lay-up, were quantitatively evaluated by performing the ablation tests with an engine torch. And their ablation discrepancies were analyzed according to the surface characteristic, porosity and thermal diffusivity. The results show that the 0°/45° weftless composite has a fiat eroded surface with no obvious macroscopic pits. Its thickness and mass erosion rates are decreased by about 46.8% and 34.8%, 25.0% and 27.5%, and 17.5% and 19.4% compared with those of the mat, the 0°/90° weftless and the 0°/45° twill composites, respectively. The ablation properties are mainly controlled by the thermo-chemical effect (oxidation), and a little by the thermo-mechanical effect (mechanical denudation). The needling fiber bundles play an important role in accelerating the ablation process and resulting in the heterogeneous ablation. 展开更多
关键词 C/C composites ablation fiber architecture isothermal chemical vapor infiltration thermal diffusivity
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DFT Studies on Thermal Stabilities,Electronic Structures,and ^(13)C Chemical Shifts of C_(24)O_2 Based on Fullerene C_(24)(D_6) 被引量:2
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作者 王振 张静 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第5期666-671,共6页
Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 (D6) and C24O have been performed using density functional theory (DFT) method. The geometric and electronic ... Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 (D6) and C24O have been performed using density functional theory (DFT) method. The geometric and electronic structures as well as the relative energies and thermal stabilities of various C24O2 isomers at the ground state have been calculated at the B3LYP/6-31G(d) level of theory. And the 1,4,2,5-C24O2 isomer was found to be the most stable geometry where two oxygen atoms were added to the longest carbon-carbon bonds in the same pentagon from a thermodynamic point of view. Based on the optimized neutral geometries, the vertical ionization potential and vertical electron affinity have been obtained. Meanwhile, the vibrational frequencies, IR spectrum, and 13C chemical shifts of various C24O2 isomers have been calculated and analyzed. 展开更多
关键词 C24O2 thermal stabilities 13C chemical shifts B3LYP/6-31G(d)
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Study of Physical, Chemical and Morphological Alterations of Smectite Clay upon Activation and Functionalization via the Acid Treatment 被引量:4
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作者 Mahmood Torabi Angaji Amir Zamani Zinali Nader Taheri Qazvini 《World Journal of Nano Science and Engineering》 2013年第4期161-168,共8页
The present study was carried out on the effect of acid leaching on the modification and structure alteration of montmorillonite. A nanostructured, activated material was prepared by selective leaching of pure smectit... The present study was carried out on the effect of acid leaching on the modification and structure alteration of montmorillonite. A nanostructured, activated material was prepared by selective leaching of pure smectite clay with different concentrations of sulfuric acid (1 - 10 N/L) at 85°C for 120 min using a solid/liquid ratio of 1:20 and a reflux system. The Fourier transform infrared (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-Ray diffraction (XRD) techniques were used for the characterization and study of the acid-treated montmorillonite clay. Chemical structure of specimens was distinguished by FTIR. The results showed that the formation of Si-OH bonds and leaching of Al3+ ions increased progressively with severity of the acid treatment. As the FTIR studies indicated, acid treatment led to the removal of the octahedral Al3+ cations and an increase in the Si-OH bonds. The morphological alteration of the untreated and treated montmorillonite was investigated by using TEM and SEM. X-ray fluorescence (XRF) analysis revealed a considerable decrease in the relative content of Al by increasing the acid strength. Moreover, the XRD results showed that the treatment using highly concentrated acid resulted in the formation of an amorphous silica phase. 展开更多
关键词 MONTMORILLONITE Acid treatment chemical ACTIVATION Morphology NANOMATERIAL Clay
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Structural Change of Wood Molecules and Chemorheological Behaviors during Chemical Treatment 被引量:1
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作者 XieManhua ZhaoGuangjie 《Forestry Studies in China》 CAS 2004年第3期55-62,共8页
It is very important to clarify the relationship of changes of molecular combinations in wood cell walls and the chemical rheological behavior during various chemical reagent treatments, for it would be helpful to dev... It is very important to clarify the relationship of changes of molecular combinations in wood cell walls and the chemical rheological behavior during various chemical reagent treatments, for it would be helpful to develop new wood modification technologies and to enrich the theory of chemical rheology of wood. Based on previous investigations on the chemorheological properties of wood by chemical treatments and the applied methods in chemical rheology of wool fibers, this paper proposes the study of various additional reagents to wood saturated in water for long periods of time in order to investigate the chemical rheology of wood, which can provide information about the character of combinations between wood molecules and the structural changes of molecules and further put forward the idea of modifying wood in a decrystallized state. 展开更多
关键词 WOOD molecular combination chemical treatment chemical rheology
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The Thermal Decomposition Mechanism and the Quantum Chemical Calculation of[Mg(H2O)6](NTO)2·2H2O 被引量:3
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作者 MAHai-xia SONGJi-rong +2 位作者 XUKang-zhen HURong-zu WENZhen-yi 《含能材料》 EI CAS CSCD 2004年第3期158-160,164,M004,共5页
[Mg(H2O)6](NTO)2·2H2O Was prepared by adding magnesium carbonate hydroxide to the aqueous solution of 3-nitro-1,2,4-triazol-5-one(NTO).Its thermal decomposition mechanism was studied by DSC,TG/DTGand IR.The... [Mg(H2O)6](NTO)2·2H2O Was prepared by adding magnesium carbonate hydroxide to the aqueous solution of 3-nitro-1,2,4-triazol-5-one(NTO).Its thermal decomposition mechanism was studied by DSC,TG/DTGand IR.The quantum chemical calculation on the title complex as a structure unit with the experimental geometry as atartmg values was carried out at B3LYP level with 6-31G basis set.The results show that the bonds between the coordinate waters and the Mgatom have certain extent covalent character.The net charges on nitrogen atoms of the NTO ring appear to be negative while the nitrogen atom on the nitro group(—NO2)appears to be positive which indicates—NO2 will lost first when the complex is heated to some uniform temperature and this result is in agreement with that of the thermal decomposition experiment. 展开更多
关键词 physical CHEMISTRY 3-nitro-1 2.4-triazol-5-one(NTO) magnesium complex thermal decomposition mechanism quantum chemical investigation
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Growth of 4" diameter polycrystailine diamond wafers with high thermal conductivity by 915 MHz microwave plasma chemical vapor deposition 被引量:1
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作者 A F POPOVICH V G RALCHENKO +6 位作者 V K BALLA A K MALLIK A A KHOMICH A P BOLSHAKOV D N SOVYK E E ASHKINAZI V Yu YUROV 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第3期93-97,共5页
Polycrystalline diamond(PCD) films 100 mm in diameter are grown by 915 MHz microwave plasma chemical vapor deposition(MPCVD) at different process parameters,and their thermal conductivity(TC) is evaluated by a l... Polycrystalline diamond(PCD) films 100 mm in diameter are grown by 915 MHz microwave plasma chemical vapor deposition(MPCVD) at different process parameters,and their thermal conductivity(TC) is evaluated by a laser flash technique(LFT) in the temperature range of230-380 K.The phase purity and quality of the films are assessed by micro-Raman spectroscopy based on the diamond Raman peak width and the amorphous carbon(a-C) presence in the spectra.Decreasing and increasing dependencies for TC with temperature are found for high and low quality samples,respectively.TC,as high as 1950 ± 230 W m-1 K-1 at room temperature,is measured for the most perfect material.A linear correlation between the TC at room temperature and the fraction of the diamond component in the Raman spectrum for the films is established. 展开更多
关键词 thermal conductivity polycrystalline diamond microwave plasma chemical vapordeposition Raman spectroscopy
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Entropy analysis in electrical magnetohydrodynamic(MHD) flow of nanofluid with effects of thermal radiation,viscous dissipation,and chemical reaction 被引量:5
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作者 Yahaya Shagaiya Daniel Zainal Abdul Aziz +1 位作者 Zuhaila Ismail Faisal Salah 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2017年第4期235-242,共8页
The unsteady mixed convection flow of electrical conducting nanofluid and heat transfer due to a permeable linear stretching sheet with the combined effects of an electric field, magnetic field, thermal radiation, vis... The unsteady mixed convection flow of electrical conducting nanofluid and heat transfer due to a permeable linear stretching sheet with the combined effects of an electric field, magnetic field, thermal radiation, viscous dissipation, and chemical reaction have been investigated. A similarity transformation is used to transform the constitutive equations into a system of nonlinear ordinary differential equations.The resultant system of equations is then solved numerically using implicit finite difference method.The velocity, temperature, concentration, entropy generation, and Bejan number are obtained with the dependence of different emerging parameters examined. It is noticed that the velocity is more sensible with high values of electric field and diminished with a magnetic field. The radiative heat transfer and viscous dissipation enhance the heat conduction in the system. Moreover, the impact of mixed convection parameter and Buoyancy ratio parameter on Bejan number profile has reverse effects. A chemical reaction reduced the nanoparticle concentration for higher values. 展开更多
关键词 Entropy generation MHD nanofluid thermal radiation Bejan number chemical reaction Viscous dissipation
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