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Annealing High Resistivity CdZnTe Wafers under Controlled Cd/Zn Partial Pressures
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作者 Wanwan LI, Wenbin SANG, Bin ZHANG, Jiahua MIN and Fang YUSchool of Material Science and Engineering, Jiading Campus, Shanghai University, Shanghai 201800, ChinaInstitute of Composites Materials, Shanghai Jiao Tong University, Shanghai 200030, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第6期703-706,共4页
In order to improve the performances of CdZnTe 7-ray detector, it is key issue to get the crystal with high quality. Equilibrium partial pressures, pCd and pZn, over Cd1-xZnx melt were estimated based on thermodynamic... In order to improve the performances of CdZnTe 7-ray detector, it is key issue to get the crystal with high quality. Equilibrium partial pressures, pCd and pZn, over Cd1-xZnx melt were estimated based on thermodynamic relationship and then Cd0.9Zn0.1Te wafers were annealed under controlled Cd/Zn partial pressures provided by Cd1-xZnx alloy reservoir. The experimental results show that when CdZnTe wafers are annealed under the equilibrium partial pressures provided by Cd0.99Zn0.01 alloy reservoir for 5 days or more at 1073 K, the resistivity of the wafer can be raised by 6 times and IR transmittance raised by 10% or more, the size and density of Te precipitates are greatly reduced. Moreover, losing of Zn from the surface can be avoided, which Ieads to improvement of the Zn radial distribution. In addition, the relationship between the electrical performances of the wafers and different controlled pressures is also discussed. 展开更多
关键词 CdZnTe annealing partial pressures over Cd_1-xZn_x γ-ray detector
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Thermokinetic and conductivity analyzes of the high CO2 chemisorption on Li5AlO4 and alkaline carbonate impregnated Li5AlO4 samples:Effects produced by the use of CO2 partial pressures and oxygen addition
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作者 Pedro Sánchez-Camacho J.Francisco Gómez-García Heriberto Pfeiffer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第5期919-926,共8页
The effect of COpartial pressure was evaluated during the COchemisorption in penta lithium aluminate(LiAlO), using different COand Opartial pressures in the presence or absence of alkaline carbonates. Results showed... The effect of COpartial pressure was evaluated during the COchemisorption in penta lithium aluminate(LiAlO), using different COand Opartial pressures in the presence or absence of alkaline carbonates. Results showed that using low PO(0.1) did not affect the kinetic and final COchemisorption process. Moreover, small additions of oxygen(PO= 0.05) into the mixture flue gas, seemed to increase the COchemisorption. Additionally, the presence of alkaline carbonates modified the COcapture temperature range. COchemisorption kinetic parameters were determined assuming a double exponential model where direct COchemisorption and COchemisorption controlled by diffusion processes are considered.Finally, ionic diffusion was analyzed by ionic conduction analysis, where all the gravimetric and ionic measurements were in good agreement showing different diffusion processes depending on temperature.Finally, the oxygen and alkaline carbonate additions have positive effects during the COchemisorption process in LiAlO, and a possible reaction mechanism is presented. 展开更多
关键词 CO2 capture Thermogravimetric analysis partial pressure Ionic conduction
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Analysis of metabolic alterations in Arabidopsis following changes in the carbon dioxide and oxygen partial pressures 被引量:2
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作者 Alexandra Florian Stefan Timm +4 位作者 Zoran Nikoloski Takayuki Tohge Hermann Bauwe Wagner L.Araujo Alisdair R.Fernie 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2014年第9期941-959,共19页
As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative ... As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas composition.However,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in general.Moreover,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains unknown.To address these questions,plants Arabidopsis thaliana(Arabidopsis) ecotype Columbia(Col-O) grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this transition.The results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite levels.The results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription. 展开更多
关键词 Carbon dioxide partial pressures gene expression metabolic profiling oxygen partial pressures
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Kinetics and rate-limiting mechanisms of dolomite dissolution at various CO_2 partial pressures 被引量:5
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作者 刘再华 DreybrodtWolfgang 《Science China Chemistry》 SCIE EI CAS 2001年第5期500-509,共10页
Techniques of rotating-disk and catalyst were used in investigating the kinetics of dolomite dissolution in flowing CO2-H2O system. Experiments run in the solutions equilibrated with various CO2 partial pressures (PCO... Techniques of rotating-disk and catalyst were used in investigating the kinetics of dolomite dissolution in flowing CO2-H2O system. Experiments run in the solutions equilibrated with various CO2 partial pressures (PCO2) from 30 to 100000 Pa. It shows that dissolution rates ofdolomite are related with rotating speeds at conditions far from equilibrium. This was explained by modified diffusion boundary layer (DBL) model. In addition, the dissolution rates increase after addition of carbonic anhydrase (CA) to solutions, where the CA catalyzes CO2 conversion. However, great differences occur among various CO2 partial pressures. The experimental observations give a conclusion that the modified DBL model enables one to predict dissolution rates and their behaviour at various PCO2 with satisfactory precision at least far from equilibrium. 展开更多
关键词 DOLOMITE dissolution rate diffusion boundary layer CO2 conversion CO2 partial pressure
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"Partial pressures" of humid air in wide pressure and temperature ranges 被引量:1
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作者 Zidong WANG Hanping CHEN Shilie WENG 《Frontiers in Energy》 SCIE CSCD 2013年第4期511-517,共7页
"Partial pressure" in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the "partial pressures" of the water ... "Partial pressure" in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the "partial pressures" of the water vapor and dry air in humid air. The results obtained by the proposed method are quite different from that obtained by Dalton's partial pressure law. The fundamental behaviors of water vapor and dry air are studied in depth in wide pressure and temperature ranges. Semi-permeable membrane models are proposed and applied for both saturated and unsaturated humid air. "Improvement factors" are developed to quantitatively describe the magnitude of the interaction between dissimilar molecules. One discovery is that the "partial pressure" of the water vapor in saturated humid air equals Ps, rather than (f.Ps) which was formerly believed. The other is that the interaction between dissimilar molecules may be omitted when temperature is above "cutting-off temperature" for unsaturated humid air. This paper satisfactorily answers the quest of "partial pressures" in humid air from a new perspective. 展开更多
关键词 partial pressure Dalton's partial pressure law humid air saturated UNSATURATED
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Oxidation of Fe-Cr-Ni Alloys in a Low Oxygen Partial Pressure Atmosphere to Mitigate Coke Formation
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作者 Wang Hongxia Wang Guoqing +3 位作者 Zhang Lijun Wang Shenxiang Jia Jingsheng Cui Lishan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第3期49-59,共11页
Anti-coking oxide films were prepared on a 25Cr35Ni and 35Cr45Ni alloy surface under the low oxygen partialpressure atmosphere of a H2-H2O mixture. The composition and phase structure of the oxide films were analyzed ... Anti-coking oxide films were prepared on a 25Cr35Ni and 35Cr45Ni alloy surface under the low oxygen partialpressure atmosphere of a H2-H2O mixture. The composition and phase structure of the oxide films were analyzed by energydispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The anti-cokingperformance of a mini tube made of a HP40 (25Cr35Ni) alloy was evaluated on a bench scale pyrolysis and coking test unit.The results showed that the surface Fe and Ni content decreased after the oxidation of the two alloys in a low oxygen partialpressure atmosphere. The oxide films were mainly composed of MnCr_(2)O_(4) and Cr_(2)O_(3). The average mass of coke in the minitube with oxide film decreased by 87% relative to that of a tube without an oxide film when the cracking temperature was 900℃. The ethylene, propylene, and butadiene yields in the pyrolysis tests were almost the same for the mini tubes withand without an oxide film. The oxide film on the alloy surface effectively inhibited catalytic filamentous coke formation.An industrial test showed that the run length of the cracking furnace with the in-situ coating technology was significantlyextended. 展开更多
关键词 Fe-Cr-Ni alloy low oxygen partial pressure oxide film ANTI-COKING ethylene cracking furnace in-situ coating
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Effect of N_(2) partial pressure on comprehensive properties of antibacterial TiN/Cu nanocomposite coating
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作者 Hui Liu Yanhui Zhao +10 位作者 Chuanshi Sui Yi Li Muhammad Ali Siddiqui Susu Li Tong Li Shuyuan Zhang Hai Wang Tao Jin Ling Ren Ke Yang Ning Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期131-143,共13页
Foreign body reactions to the wear debris and corrosion products from the implants,and bacterial infections are the main factors leading to the implant failures.In order to resolve these problems,the antibacterial TiN... Foreign body reactions to the wear debris and corrosion products from the implants,and bacterial infections are the main factors leading to the implant failures.In order to resolve these problems,the antibacterial TiN/Cu nanocomposite coatings with various N_(2) partial pressures were deposited on 304 stainless steels(SS)using an arc ion plating(AIP)system,named TiN/Cu-x(x=0.5,1.0,1.5 Pa).The results of X-ray diffraction analysis,energy-dispersive X-ray spectroscopy,and scanning electron microscopy showed that the N_(2) partial pressures determined the Cu contents,surface defects,and crystallite sizes of TiN/Cu nanocomposite coatings,which further influenced the comprehensive abilities.And the hardness and wear resistances of TiN/Cu coatings were enhanced with increase of the crystallite sizes.Under the co-actions of surface defects,crystallite sizes,and Cu content,TiN/Cu-1.0 and TiN/Cu-1.5 coatings possessed excellent corrosion resistance.Besides,the biological tests proved that all the TiN/Cu coatings showed no cytotoxicity with strong antibacterial ability.Among them,TiN/Cu-1.5 coating significantly promoted the cell proliferation,which is expected to be a novel antibacterial,corrosion-resistant,and wear-resistant coating on the surfaces of medical implants. 展开更多
关键词 N_(2)partial pressure TiN/Cu coating wear resistance corrosion behavior antibacterial ability CYTOCOMPATIBILITY
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Carbon dioxide partial pressure and its diffusion flux in karst surface aquatic ecosystems:a review
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作者 Xingxing Cao Qixin Wu +1 位作者 Wanfa Wang Pan Wu 《Acta Geochimica》 EI CAS CSCD 2023年第5期943-960,共18页
Carbon dioxide(CO_(2))emissions from aquatic ecosystems are an important component of the karst carbon cycle process and also a key indicator for assessing the effect of karst carbon sinks.This paper reviewed the CO_(... Carbon dioxide(CO_(2))emissions from aquatic ecosystems are an important component of the karst carbon cycle process and also a key indicator for assessing the effect of karst carbon sinks.This paper reviewed the CO_(2)partial pressure(pCO_(2))and its diffusion flux(FCO_(2))in karst surface aquatic ecosystems,mainly rivers,lakes,and reservoirs,and their influencing factors summarized the methods for monitoring CO_(2)emissions in karst aquatic ecosystems and discussed their adaptation conditions in karst areas.The pCO_(2)and FCO_(2)decreased in the order of rivers>reservoirs>lakes,and the values in karst lakes were eventually significantly lower than those in global lakes.The pCO_(2)and FCO_(2)of karst aquatic ecosystems had patterns of variation with diurnal,seasonal,water depth and hydrological cycles,and spatial and temporal hetero-geneity.The sources of CO_(2)in karst waters are influenced by both internal and external sources,and the key spatial and temporal factors affecting the CO_(2)emissions from karst rivers,lakes,and reservoirs were determined in terms of physicochemical indicators,biological factors,and bio-genic elements;additionally,the process of human activity interference on CO_(2)emissions was discussed.Finally,a conceptual model illustrating the impacts of urban devel-opment,agriculture,mining,and dam construction on the CO_(2)emissions at the karst surface aquatic ecosystem is presented.Meanwhile,based on the disadvantages existing in current research,we proposed several important research fields related to CO_(2)emissions from karst surface aquatic ecosystems. 展开更多
关键词 Karst area RIVER LAKE RESERVOIR partial pressure of CO_(2) CO_(2)diffusion flux
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Efficacy of Huangma Ding or autologous platelet-rich gel for the diabetic lower extremity arterial disease patients with foot ulcers
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作者 Xue-Qin Wang Dan-Lan Pu +8 位作者 Wei-Ling Leng Xiao-Tian Lei Jiang Juan Zou La Ding Yao Jia-Zhuang Xi Li Jian Teng Miao Qi-Nan Wu 《World Journal of Diabetes》 SCIE 2024年第5期923-934,共12页
BACKGROUND Diabetes foot is one of the most serious complications of diabetes and an important cause of death and disability,traditional treatment has poor efficacy and there is an urgent need to develop a practical t... BACKGROUND Diabetes foot is one of the most serious complications of diabetes and an important cause of death and disability,traditional treatment has poor efficacy and there is an urgent need to develop a practical treatment method.AIM To investigate whether Huangma Ding or autologous platelet-rich gel(APG)treatment would benefit diabetic lower extremity arterial disease(LEAD)patients with foot ulcers.METHODS A total of 155 diabetic LEAD patients with foot ulcers were enrolled and divided into three groups:Group A(62 patients;basal treatment),Group B(38 patients;basal treatment and APG),and Group C(55 patients;basal treatment and Huangma Ding).All patients underwent routine follow-up visits for six months.After follow-up,we calculated the changes in all variables from baseline and determined the differences between groups and the relationships between parameters.RESULTS The infection status of the three groups before treatment was the same.Procalcitonin(PCT)improved after APG and Huangma Ding treatment more than after traditional treatment and was significantly greater in Group C than in Group B.Logistic regression analysis revealed that PCT was positively correlated with total amputation,primary amputation,and minor amputation rates.The ankle-brachial pressure and the transcutaneous oxygen pressure in Groups B and C were greater than those in Group A.The major amputation rate,minor amputation rate,and total amputation times in Groups B and C were lower than those in Group A.CONCLUSION Our research indicated that diabetic foot ulcers(DFUs)lead to major amputation,minor amputation,and total amputation through local infection and poor microcirculation and macrocirculation.Huangma Ding and APG were effective attreating DFUs.The clinical efficacy of Huangma Ding was better than that of autologous platelet gel,which may be related to the better control of local infection by Huangma Ding.This finding suggested that in patients with DFUs combined with coinfection,controlling infection is as important as improving circulation. 展开更多
关键词 Diabetic foot ulcer Huangma Ding Autologous platelet-rich gel Ankle-brachial index Transcutaneous oxygen partial pressure
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Influence of oxygen partial pressure on properties of N-doped ZnO films deposited by magnetron sputtering 被引量:5
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作者 王金忠 E.ElANGOVAN +4 位作者 N.FRANCO A.ALVESE A.REGO R.MARTINS E.FORTUNATO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2326-2330,共5页
N-doped ZnO films were radio frequency(RF)sputtered on glass substrates and studied as a function of oxygen partial pressure(OPP)ranging from 3.0×10-4 to 9.5×10-3 Pa.X-ray diffraction patters confirmed the p... N-doped ZnO films were radio frequency(RF)sputtered on glass substrates and studied as a function of oxygen partial pressure(OPP)ranging from 3.0×10-4 to 9.5×10-3 Pa.X-ray diffraction patters confirmed the polycrystalline nature of the deposited films.The crystalline structure is influenced by the variation of OPP.Atomic force microscopy analysis confirmed the agglomeration of the neighboring spherical grains with a sharp increase of root mean square(RMS)roughness when the OPP is increased above 1.4×10-3 Pa.X-ray photoelectron spectroscopy analysis revealed that the incorporation of N content into the film is decreased with the increase of OPP,noticeably N 1s XPS peaks are hardly identified at 9.5×10-3 Pa.The average visible transmittance(380-700 nm) is increased with the increase of OPP(from~17%to 70%),and the optical absorption edge shifts towards the shorter wavelength.The films deposited with low OPP(≤3.0×10-4 Pa)show n-type conductivity and those deposited with high OPP(≥9.0×10-4 Pa)are highly resistive(>105Ω·cm) 展开更多
关键词 ZNO oxygen partial pressure magnetron sputtering TRANSMITTANCE
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THE EFFECTS OF PULSE BIAS VOLTAGE AND N_2 PARTIAL PRESSURE ON TiAlN FILMS OF ARC ION PLATING (AIP) 被引量:4
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作者 M.S. Li, S.L. Zhu, Fuhui Wang, C. Sun and L.S. Wen (Institute of Metal Research, The Chinese Academy of Sciences, Shenyang l10016, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第6期520-524,共5页
Owing to the characteristics of arc ion plating(AIP) technique, the structure and composition of TiAlN films can be tailored by controlling of various parameters such as compositions of target materials, N2 partial pr... Owing to the characteristics of arc ion plating(AIP) technique, the structure and composition of TiAlN films can be tailored by controlling of various parameters such as compositions of target materials, N2 partial pressure, substrate bias and so on. In this study, several titanium aluminum nitride films were deposited on 1Cr11Ni2W2MoV steel for compressor blade of areo-engine under different d.c pulse bias voltage and nitrogen partial pressure. The effects of substrate pulse bias and nitrogen partial pressure on the deposition rate, droplet formation, microstruture and elemental component of the films were investigated. 展开更多
关键词 TiAlN film pulse bias voltage nitrogen partial pressure arc ion plating
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Carbon dioxide partial pressure and carbon fluxes of air-water interface in Taihu Lake, China 被引量:2
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作者 范成新 胡维平 +3 位作者 Phillip W. Ford 陈宇炜 瞿文川 张路 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期29-38,共10页
To obtain carbon dioxide (CO2) flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide par... To obtain carbon dioxide (CO2) flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide partial pressures (pCO2) at air-water interface in the lake were calculated using alkalinity, pH, ionic strength, active coefficient, and water temperature. The carbon fluxes at different sublakes and areas were estimated by concentration gradient between water and air in consideration of Schmidt numbers of 600 and daily mean windspeed at 10 m above water surface. The results indicated that the mean values of pCO2 in Wuli Lake,Meiliang Bay, hydrophyte area, west littoral zone, riverine mouths, and the open lake areas were 1 807.8±1 071.4(mean±standard deviation)μatm (latm=1.013 25×10^5pa), 416.3±217.0μatm, 576.5±758.8μatm, 304.2±9.43.5μatm, 1 933.6±1 144.7 μatm, and 448.5±202.6μatm, respectively. Maximum and minimum pCO2 values were found in the hypertrophic (4 053.7μatm) and the eutrophic (3.2 μatm) areas. The riverine mouth areas have the maximum fluxes (82.0±62.8 mmol/m^2a). But there was no significant difference between eutrophic and mesotrophic areas in pCO2 and the flux of CO2. The hydrophyte area, however, has the minimum (--0.58±12.9mmol/m^2a). In respect to CO2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. For example, the annual mean CO2 flux in Zhihugang River estuary was 19 times of that in Meiliang Bay, although the former is only a part of the latter. The sites in the body of the lake show a clear seasonal cycle with pCO2 higher than atmospheric equilibrium in winter, and much lower than atmospheric in summer due to CO2 consumption by photosynthesis. The CO2 amount of the net annual evasion that enters the atmosphere is 28.42×10^4 t/a, of which those from the west littoral zone and the open lake account for 53.8% and 36.7%, respectively. 展开更多
关键词 carbon dioxide partial pressure air-water interface carbon flux trophic area river input Taihu Lake
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A new dynamic method for measuring hydrogen partial pressure in molten aluminum alloy 被引量:3
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作者 Sun Qian Li Dayong +1 位作者 Wang Lihua Zhang Jianlei 《China Foundry》 SCIE CAS 2011年第1期1-4,共4页
Hydrogen partial pressure is an important parameter to calculate hydrogen concentration levels in molten aluminum alloy. A new dynamic method for measuring hydrogen partial pressure in molten aluminum alloy is studied... Hydrogen partial pressure is an important parameter to calculate hydrogen concentration levels in molten aluminum alloy. A new dynamic method for measuring hydrogen partial pressure in molten aluminum alloy is studied. Dynamic and rapid measurement is realized through changing the volume of the vacuum chamber and calculating the pressure difference ΔP between the theoretical and measured pressures in the vacuum chamber. Positive ΔP indicates hydrogen transmits from melt to vacuum chamber and negative ΔP means the reverse. When ΔP is equal to zero, hydrogen transmitted from both sides reached a state of dynamical equilibrium and the pressure in the vacuum chamber is equal to the hydrogen partial pressure in the molten aluminum alloy. Compared with other existing measuring methods, the new method can significantly shorten the testing time and reduce measuring cost. 展开更多
关键词 molten aluminum alloy hydrogen partial pressure dynamic measurement rapid measurement
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The Effect of Oxygen Partial Pressure during Active Layer Deposition on Bias Stability of a-InGaZnO TFTs 被引量:2
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作者 黄晓明 武辰飞 +3 位作者 陆海 任芳芳 朱洪波 王永进 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期171-174,共4页
The effect of oxygen partial pressure (Po2) during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) is investigated. As Po2 increases fr... The effect of oxygen partial pressure (Po2) during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) is investigated. As Po2 increases from 10% to 30%, it is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on the x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies (Or) within the a-IGZO layer is suppressed by increasing Po2. Meanwhile, the low-frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops with increasing Po2. Therefore, the improved interface quality with increasing Po2 during the channel layer deposition can be attributed to the reduction of interface Ov-related defects, which agrees with the enhanced bias stress stability of the a-IGZO TFTs. 展开更多
关键词 TFT The Effect of Oxygen partial Pressure during Active Layer Deposition on Bias Stability of a-InGaZnO TFTs
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Effect of N_2-Gas Partial Pressure on the Structure and Properties of Copper Nitride Films by DC Reactive Magnetron Sputtering
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作者 刘祖黎 李兴鳌 +3 位作者 左安友 袁作彬 杨建平 姚凯伦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第2期147-151,共5页
Copper nitride thin films were deposited on glass substrates by reactive direct current (DC) magnetron sputtering at various N2-gas partial pressures and room temperature. Xray diffraction measurements showed that t... Copper nitride thin films were deposited on glass substrates by reactive direct current (DC) magnetron sputtering at various N2-gas partial pressures and room temperature. Xray diffraction measurements showed that the films were composed of Cu3N crystallites and exhibited a preferential orientation of the [111] direction at a low nitrogen gas (N2) partial pressure. The film growth preferred the [111] and the [100] direction at a high N2 partial pressure. Such preferential film growth is interpreted as being due to the variation in the Copper (Cu) nitrification rate with the N2 pressure. The N2 partial pressure affects not only the crystal structure of the film but also the deposition rate and the resistivity of the Cu3N film. In our experiment, the deposition rate of Cu3N films was 18 nm/min to 30 nm/min and increased with the N2 partial pressure. The resistivity of the Cu3N films increased sharply with the increasing N2 partial pressure. At a low N2 partial pressure, the Cu3N films showed a metallic conduction mechanism through the Cu path, and at a high N2 partial pressure, the conductivity of the Cu3N films showed a semiconductor conduction mechanism. 展开更多
关键词 Cu3N film DC magnetron sputtering N2-gas partial pressure RESISTIVITY
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Effect of Oxygen Partial Pressure on Epitaxial Growth and Properties of Laser-Ablated AZO Thin Films
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作者 王传彬 LUO Sijun +1 位作者 SHEN Qiang 张联盟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期27-30,共4页
Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well a... Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well as the electrical and optical properties of the films was investigated.The structure characterizations indicated that the as-grown films were single-phased with a wurtzite ZnO structure,showing a significant c-axis orientation.The films were well crystallized and exhibited better crystallinity and denser texture when deposited at higher P_(O2).At the optimum oxygen partial pressures of 10- 15 Pa,the AZO thin films were epitaxially grown on c-sapphire substrates with the(0001) plane parallel to the substrate surface,i e,the epitaxial relationship was AZO(000 1) // A1_2O_3(000 1).With increasing P_(O2),the value of Hall carrier mobility was increased remarkably while that of carrier concentration was decreased slightly,which led to an enhancement in electrical conductivity of the AZO thin films.All the films were highly transparent with an optical transmittance higher than 85%. 展开更多
关键词 AZO thin films epitaxial growth laser ablation oxygen partial pressure electrical and optical properties
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Partially Diffusive Helium-Silica Compound under High Pressure
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作者 Cong Liu Junjie Wang +7 位作者 Xin Deng Xiaomeng Wang Chris J.Pickard Ravit Helled Zhongqing Wu Hui-Tian Wang Dingyu Xing Jian Sun 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期52-57,共6页
Helium is the second most abundant element in the universe, and together with silica, they are important components of giant planets. Exploring the reactivity and state of helium and silica under high pressure is cruc... Helium is the second most abundant element in the universe, and together with silica, they are important components of giant planets. Exploring the reactivity and state of helium and silica under high pressure is crucial for understanding of the evolution and internal structure of giant planets. Here, using first-principles calculations and crystal structure predictions, we identify four stable phases of a helium-silica compound with seven/eight-coordinated silicon atoms at pressure of 600–4000 GPa, corresponding to the interior condition of the outer planets in the solar system. The density of He Si O2 agrees with current structure models of the planets.This helium-silica compound exhibits a superionic-like helium diffusive state under the high-pressure and hightemperature conditions along the isentropes of Saturn, a metallic fluid state in Jupiter, and a solid state in the deep interiors of Uranus and Neptune. These results show that helium may affect the erosion of the rocky core in giant planets and may help to form a diluted core region, which not only highlight the reactivity of helium under high pressure but also provide evidence helpful for building more sophisticated interior models of giant planets. 展开更多
关键词 RED partially Diffusive Helium-Silica Compound under High Pressure
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Preparation of ultrafine rhenium powders by CVD hydrogen reduction of volatile rhenium oxides 被引量:9
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作者 白猛 刘志宏 +2 位作者 周乐君 刘智勇 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期538-542,共5页
A novel CVD process for the preparation of ultrafine rhenium powders was investigated using ammonium perrhenate as starting materials. In the process, volatile rhenium oxides, such as ReO4 and Re2O7, were vaporized un... A novel CVD process for the preparation of ultrafine rhenium powders was investigated using ammonium perrhenate as starting materials. In the process, volatile rhenium oxides, such as ReO4 and Re2O7, were vaporized under a controlled oxidizing atmosphere via the pyrolysis of ammonium perrhenate, and carried into reduction zone by carrier gas, and there reduced into rhenium powders by hydrogen gas. Thermodynamic calculations indicated that Re207 could be prevented from further decomposition through controlling the oxygen partial pressure higher than 10 1.248 Pa in the pyrolysis of ammonium perrhenate. This result was further validated via DSC-TGA analysis of ammonium perrhenate. The typical rhenium powders prepared by the CVD method proposed show irregular polyhedron morphology with particle size in the range of 100-800 nm and a Ds0 of 308 nm. The specific surface area and oxygen content were measured to be 4.37 m^2/g and 0.45%, respectively. 展开更多
关键词 ultrafme rhenium powders ammonium perrhenate chemical vapor decomposition oxygen partial pressure
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Formation mechanism and oxidation behavior of MoSi_2-SiC protective coating prepared by chemical vapor infiltration/reaction 被引量:5
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作者 何子博 李贺军 +2 位作者 史小红 付前刚 吴恒 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2100-2106,共7页
In order to protect C/C composites from oxidation, SiC-MoSi2 composite coating was synthesized by chemical vapor infiltration /reaction (CVI/CVR) technology. A porous Mo layer was prefabricated on SiC coated C/C com... In order to protect C/C composites from oxidation, SiC-MoSi2 composite coating was synthesized by chemical vapor infiltration /reaction (CVI/CVR) technology. A porous Mo layer was prefabricated on SiC coated C/C composites, and then MoSi2 and SiC were subsequently prepared in a CVI /CVR process using methyltrichlorosilane (MTS) as precursor. The deposition and reaction mechanism of the MoSi2-SiC composite coating was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The oxidation behavior of SiC-MoSi2 coated specimens was tested. The results show that the porous Mo layer can be densified with SiC phase decomposed from MTS, and transformed into SiC-MoSi2 by reacting with MTS as well. A dense composite coating was prepared with optimized deposition parameters. The coated specimen exhibits a good oxidation resistance with a little mass loss of 1.25% after oxidation at 1500 °C for 80 h. 展开更多
关键词 MoSi2-SiC coating deposition temperature initial partial pressure of MTS oxidation resistance
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Oxidation behavior of C/C composites with SiC/ZrSiO_4-SiO_2 coating 被引量:3
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作者 李杨 肖鹏 +2 位作者 李专 罗威 周伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期397-405,共9页
A SiC/ZrSiO4?SiO2 (SZS) coating was successfully fabricated on the carbon/carbon (C/C) composites by pack cementation, slurry painting and sintering to improve the anti-oxidation property and thermal shock r... A SiC/ZrSiO4?SiO2 (SZS) coating was successfully fabricated on the carbon/carbon (C/C) composites by pack cementation, slurry painting and sintering to improve the anti-oxidation property and thermal shock resistance. The anti-oxidation properties under different oxygen partial pressures (OPP) and thermal shock resistance of the SZS coating were investigated. The results show that the SZS coated sample under low OPP, corresponding to the ambient air, during isothermal oxidation was 0.54% in mass gain after 111 h oxidation at 1500 ° C and less than 0.03% in mass loss after 50 h oxidation in high OPP, corresponding to the air flow rate of 36 L/h. Additionally, the residual compressive strengths (RCS) of the SZS coated samples after oxidation for 50 h in high OPP and 80 h in low OPP remain about 70% and 72.5% of those of original C/C samples, respectively. Moreover, the mass loss of SZS coated samples subjected to the thermal cycle from 1500 ° C in high OPP to boiling water for 30 times was merely 1.61%. 展开更多
关键词 C/C composite SiC/ZrSiO4-SiO2 coating oxygen partial pressure ANTI-OXIDATION thermal shock residual compressive strength
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