In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obta...In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obtained to release the strain caused by the lattice and thermal mismatch between a-GaN and r-sapphire.We find that the thickness of InGaN has a great influence on the growth of a-GaN.The surface morphology and crystalline quality both are first improved and then deteriorated with increasing the thickness of the InGaN interlayer.When the InGaN thickness exceeds a critical point,the a-GaN epilayer peels off in the process of cooling down to room temperature.This is an attractive way of lifting off a-GaN films from the sapphire substrate.展开更多
A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,th...A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,the formation water and rock components in the Tahe Oilfield,the long-term thermal stability,salt tolerance and the ability to change the wettability,interfacial activity and oil washing efficiency of the mixed surfactant system were studied.The system contains the anionic surfactant SDB and another cationic surfactant SDY.When the total mass concentration of the SS solution is 0.15 wt%,m(SDB)/m(SDY)ratio is 1 to 1,and excellent efficiencies are achieved for oil washing for five kinds of Tahe Oilfield crude oils(more than 60%).In addition,after adding cationic surfactant,the adsorption capacity of the surfactant is further reduced,reaching 0.261 mg/g.The oil displacement experiments indicate that under a temperature of 150°C and a salinity of 24.6×104 mg/L,the SS system enhances the oil recovery by over 10%after water flooding.The SS anionic–cationic surfactant system is first presented in the open literature that can be successfully applied to obtain predictions of Tahe Oilfield carbonate reservoirs with a high temperature and high salinity.展开更多
This paper describes the platformisation of the mobile services domain,which in recent years has become a successful strategy for some hardware manufacturers and software companies.While having different platform stra...This paper describes the platformisation of the mobile services domain,which in recent years has become a successful strategy for some hardware manufacturers and software companies.While having different platform strategies and business models,they have succeeded in creating a demand for mobile software and content with end-users.This paper proposes a way to determine the optimum platform-charging mode that an operator should adopt to play a meaningful role in the mobile service domain and with respect to content with end-users.Four charging modes employed by mobile application stores are studied in this paper,namely the one-sided paid-by-users charging mode,the one-sided paid-by-advertisers charging mode,the two-sided differential paid charging mode and the two-sided paid and free access charging mode.Furthermore,a comparative analysis of the four modes is also presented.展开更多
We report the effect of the GaAs spacer layer thickness on the photoluminescence （PL） spectral bandwidth of InAs/GaAs self-assembled quantum dots （QDs）. A PL spectral bandwidth of 158 nm is achieved with a five-la...We report the effect of the GaAs spacer layer thickness on the photoluminescence （PL） spectral bandwidth of InAs/GaAs self-assembled quantum dots （QDs）. A PL spectral bandwidth of 158 nm is achieved with a five-layer stack of InAs QDs which has a 11-nm thick GaAs spacer layer. We investigate the optical and the structurM properties of the multilayer-stacked InAs/GaAs QDs with different GaAs spacer layer thicknesses. The results show that the spacer thickness is a key parameter affecting the multi-stacked InAs/GaAs QDs for wide-spectrum emission.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.91233111,61274041,and 11275228)the Special Funds for Major State Basic Research Project of China(Grant No.2012CB619305)+1 种基金the National High Technology R&D Program of China(Grant Nos.2014AA032603 and2014AA032609)the Guangdong Provincial Special Fund for LED Industrial Development,China(Grant No.2012A080302003)
文摘In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obtained to release the strain caused by the lattice and thermal mismatch between a-GaN and r-sapphire.We find that the thickness of InGaN has a great influence on the growth of a-GaN.The surface morphology and crystalline quality both are first improved and then deteriorated with increasing the thickness of the InGaN interlayer.When the InGaN thickness exceeds a critical point,the a-GaN epilayer peels off in the process of cooling down to room temperature.This is an attractive way of lifting off a-GaN films from the sapphire substrate.
基金The support from the China National High Technology Research and Development Program(No.2013AA064301)the National Natural Science Foundation of China(51274210)the Research Start-up Fund of Karamay Campus of China University of Petroleum-Beijing(XQZX20200013)is greatly appreciated.
文摘A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,the formation water and rock components in the Tahe Oilfield,the long-term thermal stability,salt tolerance and the ability to change the wettability,interfacial activity and oil washing efficiency of the mixed surfactant system were studied.The system contains the anionic surfactant SDB and another cationic surfactant SDY.When the total mass concentration of the SS solution is 0.15 wt%,m(SDB)/m(SDY)ratio is 1 to 1,and excellent efficiencies are achieved for oil washing for five kinds of Tahe Oilfield crude oils(more than 60%).In addition,after adding cationic surfactant,the adsorption capacity of the surfactant is further reduced,reaching 0.261 mg/g.The oil displacement experiments indicate that under a temperature of 150°C and a salinity of 24.6×104 mg/L,the SS system enhances the oil recovery by over 10%after water flooding.The SS anionic–cationic surfactant system is first presented in the open literature that can be successfully applied to obtain predictions of Tahe Oilfield carbonate reservoirs with a high temperature and high salinity.
基金supported by the National Natural Science Foundation of China under Grant No.61071077
文摘This paper describes the platformisation of the mobile services domain,which in recent years has become a successful strategy for some hardware manufacturers and software companies.While having different platform strategies and business models,they have succeeded in creating a demand for mobile software and content with end-users.This paper proposes a way to determine the optimum platform-charging mode that an operator should adopt to play a meaningful role in the mobile service domain and with respect to content with end-users.Four charging modes employed by mobile application stores are studied in this paper,namely the one-sided paid-by-users charging mode,the one-sided paid-by-advertisers charging mode,the two-sided differential paid charging mode and the two-sided paid and free access charging mode.Furthermore,a comparative analysis of the four modes is also presented.
基金Project supported by the National Basic Research Program of China (Grant No. 2006CB604904)the National Natural Science Foundation of China (Grant Nos. 60976057,61274072,and 60776037)
文摘We report the effect of the GaAs spacer layer thickness on the photoluminescence （PL） spectral bandwidth of InAs/GaAs self-assembled quantum dots （QDs）. A PL spectral bandwidth of 158 nm is achieved with a five-layer stack of InAs QDs which has a 11-nm thick GaAs spacer layer. We investigate the optical and the structurM properties of the multilayer-stacked InAs/GaAs QDs with different GaAs spacer layer thicknesses. The results show that the spacer thickness is a key parameter affecting the multi-stacked InAs/GaAs QDs for wide-spectrum emission.
