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Compositions,Proportions,and Equilibrium Temperature of Coexisting Two-feldspar in Crystalline Rocks 被引量:1
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作者 MA Hongwen YANG Jing +1 位作者 SU Shuangqing YAO Wengui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期875-881,共7页
Compositions, proportions, and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis. Crystalline rocks are... Compositions, proportions, and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis. Crystalline rocks are usually composed of 4-6 minerals (phases), depending on their independent chemical components and the equilibrium temperature of crystallizations. In general, number of mineral phases can be determined by the "Phase Rule". According to the mass balance principle, bulk composition of coexisting two-feldspar could be evaluated from the bulk chemistry of a rock, provided that the compositions of the coexisting mafic mineral phases containing calcium, sodium, and potassium oxides are determined, e.g., by microprobe analysis. The compositions, proportions, and temperature of two-feldspar in equilibrium can thus be simultaneously resolved numerically from bulk composition of the rock, by incorporating the activity/composition relations of the ternary feldspars with the mass balance constraints. Upon the numerical approximation method presented in this paper, better-quality, internally consistent data on feldspar group could usually be obtained, which would be expected more realistic and accurate in consideration of thermodynamic equilibria in the system of crystalline rocks, as well as bulk chemistry of a rock and the composing minerals. 展开更多
关键词 crystalline rocks mass balance principle feldspar proportion activity equation equilibrium temperature
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Fe^(2+)SITE OCCUPANCY IN CUMMINGTONITEGRUNERITE AND ESTIMATION OF EQUILIBRIUM TEMPERATURE
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作者 应育浦 李幼琴 孙传敏 《Chinese Science Bulletin》 SCIE CAS 1989年第23期1975-1979,共5页
One of the important applications of M?ssbauer effect in mineralogy is the measurement of cation site occupancy in minerals. The combination of M?ssbauer effect and infrared Spectrum will be a more effective method fo... One of the important applications of M?ssbauer effect in mineralogy is the measurement of cation site occupancy in minerals. The combination of M?ssbauer effect and infrared Spectrum will be a more effective method for Fe and Mg order-disorder measurement of amphibole. Some results of studies on cummingtonite-grunerite by this method 展开更多
关键词 Mossbauer spectrum CUMMINGTONITE Fe^(2+)site occupancy equilibrium temperature
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DENSITY, EQUILIBRIUM HEAT OF FUSION AND EQUILIBRIUM MELTING TEMPERATURE OF NYLON 1010
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作者 冯金华 莫志深 陈东霖 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第1期61-68,共8页
The density, equilibrium heat of fusion and equilibrium melting temperature of Nylon 1010 were determined by means of infrared spectrum, differential scanning calorimetry, wide angle X-ray diffraction and density meas... The density, equilibrium heat of fusion and equilibrium melting temperature of Nylon 1010 were determined by means of infrared spectrum, differential scanning calorimetry, wide angle X-ray diffraction and density measurement techniques. According to Starkweatber' s method crystalline density ρ_c and amorphous density ρ_a were estimated to be 1.098 and 1.003 g/cm^3 respectively by extrapolating the straight lines of the IR absorbanee against density to zero intensity. Owing to the less intense in absorbance and less sensitive to the change in crystallinity of the amorphors band the thus obtained ρ_c was too low in value. Thereby the value of the ratio ρ_c /ρ_a is far less than generally accepted mean value for most crystalline polymers. Accordingly, traditional X-ray diffraction method was used through determining thc crystalline dimension(a=4.9, b=5.4, c=27.8, α=49° β=77.0°, γ=63.5°), and a rather correct value of ρ_c or the crystal density 1.13 g/cm^3 was obtained. The equilibrium heat of fusion △H_m^0 was estimated to be 244.0 J/g piotting △H_m 's of specimens with different crystallinity against their corre sponding specific volumes_(sp), and extrapolating to completely crystalline condition (_(sp)~c= 1/ρ_c) As to the equilibrium melting temperature T_m^0, because of the easiness of recrystallization of melt crystallized Nylon 1010 specimen, the well-known Hoffman's T_m-T_c method failed in determining this value and an usually rarely used Kamide double extrapolation method was adopted. The so obtained value of T_m^0 487 seems to be fairly reasonable. 展开更多
关键词 Nylon 1010 Crystalline and amorphous densities Equilibrirm heat of fusion equilibrium melting temperature.
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Effect of particle gradation of aluminum on the explosion field pressure and temperature of RDX-based explosives in vacuum and air atmosphere 被引量:9
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作者 Fan Jiang Xiao-feng Wang +4 位作者 Ya-feng Huang Bo Feng Xuan Tian Yu-lei Niu Kun Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第6期844-852,共9页
To optimize the energy output and improve the energy utilization efficiency of an aluminized explosive,an explosion device was developed and used to investigate the detonation pressure and temperature of R1(A16)alumin... To optimize the energy output and improve the energy utilization efficiency of an aluminized explosive,an explosion device was developed and used to investigate the detonation pressure and temperature of R1(A16)aluminum powder and the aluminum powder particle gradation of R2(Al6+Al13),R3(Al6+Al24)and R4(Al6+AI flake)in a confined space.By using gas chromatography,quantitative analysis and calculations were carried out to analyze the gaseous detonation products.Finally,the reaction ratios of the aluminum powder and the explosion reaction equations were calculated.The results show that in a confined space,the quasi-static pressures and equilibrium temperature of the aluminum powder in air are higher than in vacuum.In vacuum,the quasi-static pressures and equilibrium temperatures of the samples in descending order are R1>R3>R4>R2 and R3>R4>R1>R2,respectively.In air,the quasi-static pressures and equilibrium telperatures of the samples in descending order are R1>R2>R4>R3 and R1>R4>R2>R3,respectively.R4(Al6+AI flake)and R3(Al6+A124)have relatively higher temperatures after detonation,which shows that the particle gradation method can enhance the reaction energy output of aluminum during the initial reaction stage of the explosion and increase the reaction ratio by10.6%and 8.0%,respectively.In air,the reaction ratio of AI6 aluminum powder can reach as high as 78.16%,and the reaction ratio is slightly reduced after particle gradation.Finally,the reaction equations of the explosives in vacuum and in air were calculated by quantitative analysis of the explosion products,which provides a powerful basis for the study of RDX-based explosive reactions. 展开更多
关键词 Particle gradation Quasi-static pressure equilibrium temperature Reaction ratio
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Isotopic Compositions of Sulfur in the Jinshachang Lead–Zinc Deposit, Yunnan, China, and its Implication on the Formation of Sulfur-Bearing Minerals 被引量:9
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作者 BAI Junhao HUANG Zhilong +2 位作者 ZHU Dan YAN Zaifei ZHOU Jiaxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1355-1369,共15页
The Jinshachang lead-zinc deposit is mainly hosted in the Upper Neoproterozoic carbonate rocks of the Dengying Group and located in the Sichuan-Yunnan-Guizhou (SYG) Pb-Zn-Ag multi- metal mineralization area in China... The Jinshachang lead-zinc deposit is mainly hosted in the Upper Neoproterozoic carbonate rocks of the Dengying Group and located in the Sichuan-Yunnan-Guizhou (SYG) Pb-Zn-Ag multi- metal mineralization area in China. Sulfides minerals including sphalerite, galena and pyrite postdate or coprecipitate with gangue mainly consisting of fluorite, quartz, and barite, making this deposit distinct from most lead-zinc deposits in the SYG. This deposit is controlled by tectonic structures, and most mineralization is located along or near faults zones. Emeishan basalts near the ore district might have contributed to the formation of orebodies. The j34S values of sphalerite, galena, pyrite and barite were estimated to be 3.6‰-13.4‰, 3.7‰-9.0‰, -6.4‰ to 29.2‰ and 32.1‰34.7‰, respectively. In view of the similar δ34S values of barite and sulfates being from the Cambrian strata, the sulfur of barite was likely derived from the Cambrian strata. The homogenization temperatures (T ≈ 134--383℃) of fluid inclusions were not suitable for reducing bacteria, therefore, the bacterial sulfate reduction could not have been an efficient path to generate reduced sulfur in this district. Although thermochemical sulfate reduction process had contributed to the production of reduced sulfur, it was not the main mechanism. Considering other aspects, it can be suggested that sulfur of sulfides should have been derived from magmatic activities. The δ34S values of sphalerite were found to be higher than those of coexisting galena. The equilibrium temperatures calculated by using the sulfur isotopic composition of mineral pairs matched well with the homogenization temperature of fluid inclusions, suggesting that the sulfur isotopic composition in ore-forming fluids had reached a partial equilibrium. 展开更多
关键词 sulfur isotopic composition thermochemical sulfate reduction homogenization temperature equilibrium temperature Jinshachang lead-zinc deposit
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Equilibrium Crystallization Temperature of Syndiotactic Polystyrene γ Form
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作者 Hai Wang Chun-Ji Wu +1 位作者 Dong-Mei Cui Yong-Feng Men 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第6期749-755,共7页
The crystallization behavior of syndiotactic polystyrene(s PS) γ form undergoing annealing at various temperatures was investigated using the thermodynamic phase diagram based on Strobl's crystallization theory. O... The crystallization behavior of syndiotactic polystyrene(s PS) γ form undergoing annealing at various temperatures was investigated using the thermodynamic phase diagram based on Strobl's crystallization theory. On the basis of the differential scanning calorimetric results, it was observed that γ form melt-recrystallization occurred at a higher temperature with the increasing lamellar thickness, which resulted from the pre-annealing at the elevating temperature after acetone induced crystallization. Further temperature dependent small-angle X-ray scattering(SAXS) measurement revealed the evolution of the γ form lamellae upon heating until phase transition, involving three different regimes: lamellae stable region(25-90 °C), melt-recrystallization region(90-185 °C) and pre-phase transition region(185-195 °C). As a result, recrystallization line, equilibrium recrystallization line and melting line were developed for the s PS γ form crystallization process. Since the melt of γ form involved a γ-to-α/β form phase transition, the melting line was also denoted as the phase transition line in this special case. Therefore, the equilibrium crystallization temperature and melting(phase transition) temperatures were determined at around 390 and 220 °C on the basis of the thermodynamic phase diagram of the s PS γ form. 展开更多
关键词 Syndiotactic polystyrene γ form Crystallization behavior equilibrium crystallization temperature equilibrium melting temperature
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A Mechanical and Experimental Study on the Heat Loss of Solar Evacuated Tube 被引量:1
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作者 赵惠忠 刘震炎 +3 位作者 张敏 黄晨 王丽慧 邹志军 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第1期52-57,共6页
The experimental system of heat loss of all-glass evacuated solar collector tubes(evacuated tube) is firstly designed and constructed,which uses electric heater as thermal resource.The equilibrium temperatures are les... The experimental system of heat loss of all-glass evacuated solar collector tubes(evacuated tube) is firstly designed and constructed,which uses electric heater as thermal resource.The equilibrium temperatures are less than±1℃during the test.and the temperature differences of up/middle/low node in the tube are less than 1℃,3℃,and 7℃respectively.The heat loss of evacuated tube increases about 2.7%with vacuum state of 0.01--1 mPa,and it has the best performance at tube temperature of 20--280℃.The invalidation tube(>200 mPa) has the biggest heat loss that increases linearly with the tube temperature.The evacuated tubes with the vacuum of 0.01-1 mPa are suitable for most solar adsorption refrigeration. 展开更多
关键词 all-glass evacuated solar collector tube adsorption refrigeration vacuum state heat loss equilibrium temperature
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Experimental investigation of eutectic point in Al-rich Al-La, Al-Ce, Al-Pr and Al-Nd systems 被引量:4
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作者 曹祖军 孔纲 +2 位作者 车淳山 王彦启 彭浩棠 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第10期1022-1028,共7页
In order to confirm the eutectic composition, eutectic temperature and phases of Al-rich Al-RE(La, Ce, Pr, Nd) binary systems, the eutectic Al-RE alloys with the controversial compositions were investigated. The sca... In order to confirm the eutectic composition, eutectic temperature and phases of Al-rich Al-RE(La, Ce, Pr, Nd) binary systems, the eutectic Al-RE alloys with the controversial compositions were investigated. The scanning electron microscopy/energy dispersive spectroscopy(SEM/EDS), differential scanning calorimetric(DSC) and cooling curve tests analysis indicated that a similar eutectic composition(~12 wt.% RE) on the Al-rich region was observed in the Al-La, Al-Ce, Al-Pr and Al-Nd alloys, and the eutectic structure of the alloys was consisted of α-Al and α-Al11RE3 phases by combining with X-ray diffraction(XRD) tests. In addition, the eutectic temperatures determined by DSC and cooling curve tests were very close and around 645 oC. 展开更多
关键词 aluminum-rare earth alloys eutectic composition eutectic temperature equilibrium phase
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