Based on the simulated laboratory experiment of pressure balance for fire ex- tinguishing,the pressure regulating technology was summarized for the fire district in Meiyukou Coal Mine.The technology includes three mea...Based on the simulated laboratory experiment of pressure balance for fire ex- tinguishing,the pressure regulating technology was summarized for the fire district in Meiyukou Coal Mine.The technology includes three measures for air pressure regulation, namely applying the pressure regulating chamber to balance the air pressure of fire district, increasing the air pressure of the working face,and filling the ground surface fractures.A good effect was obtained to prevent and extinguish the fire.When the measures fail to in- crease the pressure of working face or to regulate that of air chamber,the measure to fill the ground surface fractures will play an important role.展开更多
In this paper, co-doping method is used to improve the current efficiency of solution-processed organic light-emitting diodes(OLEDs). By changing the ratio of two thermally activated delayed fluorescent(TADF) emitters...In this paper, co-doping method is used to improve the current efficiency of solution-processed organic light-emitting diodes(OLEDs). By changing the ratio of two thermally activated delayed fluorescent(TADF) emitters, we studied the performance of device and its mechanism. A solution processed OLED with a structure of indium tin oxide(ITO, 150 nm)/PEDOT:PSS(30 nm)/CBP:4 Cz IPN-x%:4 Cz PN-y%(30 nm)/TPBi(40 nm)/Li F(1 nm)/Al(100 nm) was fabricated. The current efficiencies of 26.6 cd/A and 26.4 cd/A were achieved by the devices with dopant ratio of 6% 4 Cz IPN:2% 4 Cz PN and 2% 4 Cz IPN:6% 4 Cz PN in emitting material layer(EML), respectively. By investigating the tendency of current density change in devices with different doping ratio, we suggested that the enhancement of the current efficiency should be due to the charge transport balance improvement induced by assist dopant in EML.展开更多
Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too ...Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.展开更多
Hanging glaciers hold the absolute dominant number in West China and their changes had important influences on local hydrology,sea-level rise and natural hazards(snow/ice avalanches).However,logistic and operational d...Hanging glaciers hold the absolute dominant number in West China and their changes had important influences on local hydrology,sea-level rise and natural hazards(snow/ice avalanches).However,logistic and operational difficulties have resulted in the lack of in-situ-measured data,leaving us with poor knowledge of the changing behaviors of this type of glacier.Here,we presented the spatiotemporal pattern of seasonal and annual mass changes of a mid-latitude hanging glacier in the Tien Shan based on repeated terrestrial laser scanning(TLS)surveys during the period 2016-2018.The distributed glacier surface elevation changes exhibited highly spatiotemporal variability,and the winter elevation changes showed slight surface lowering at the upper elevations and weak thickening at the glacier terminus,which was contrary to altitudinal elevation changing patterns at the summer and annual scales.Mass balance processes of the hanging glacier mainly occurred during summer and the winter mass balance was nearly balanced(-0.10±0.15 m w.e.).The glacier exhibited more rapid mass loss than adjacent other morphological glacier and the estimated response time of the glacier to climate change was very short(6-9 years),indicating hanging glaciers will experience rapid wastage and disappearance in the future even with climate change mitigation.展开更多
基金the Natural Science Foundation of Liaoning Province(20060390)
文摘Based on the simulated laboratory experiment of pressure balance for fire ex- tinguishing,the pressure regulating technology was summarized for the fire district in Meiyukou Coal Mine.The technology includes three measures for air pressure regulation, namely applying the pressure regulating chamber to balance the air pressure of fire district, increasing the air pressure of the working face,and filling the ground surface fractures.A good effect was obtained to prevent and extinguish the fire.When the measures fail to in- crease the pressure of working face or to regulate that of air chamber,the measure to fill the ground surface fractures will play an important role.
基金supported by the National High Technology Research and Development Program of China (No.2012AA011901)the National Program on Key Basic Research Project of China (No.2012CB723406)+2 种基金the National Natural Science Foundation of China (No.51573036)the Fundamental Research Funds for the Central Universities of China (No.JD2016JGPY0007)the Industry-University-Research Cooperation Project of Aviation Industry Corporation of China (No.CXY2013HFGD20)。
文摘In this paper, co-doping method is used to improve the current efficiency of solution-processed organic light-emitting diodes(OLEDs). By changing the ratio of two thermally activated delayed fluorescent(TADF) emitters, we studied the performance of device and its mechanism. A solution processed OLED with a structure of indium tin oxide(ITO, 150 nm)/PEDOT:PSS(30 nm)/CBP:4 Cz IPN-x%:4 Cz PN-y%(30 nm)/TPBi(40 nm)/Li F(1 nm)/Al(100 nm) was fabricated. The current efficiencies of 26.6 cd/A and 26.4 cd/A were achieved by the devices with dopant ratio of 6% 4 Cz IPN:2% 4 Cz PN and 2% 4 Cz IPN:6% 4 Cz PN in emitting material layer(EML), respectively. By investigating the tendency of current density change in devices with different doping ratio, we suggested that the enhancement of the current efficiency should be due to the charge transport balance improvement induced by assist dopant in EML.
基金Financial support from the following projects and organisa- tions are acknowledged： the China One Thousand Talent Scheme, the National Natural Science Foundation of China （NNSFC） under its Major Research Scheme of Meso-scale Mechanism and Control in Multi-phase Reaction Processes （project reference： 91434126）, the Natural Science Foundation of Guangdong Province （project reference： 2014A030313228）, the UK Engineering and Physical Sciences Research Council （EPSRC） for the projects of Shape （EP/C009541） and StereoVision （EP/E045707）, and the Technology Strategy Board （TSB） for the project of High Value Manufacturing CGM （TP/BD059E）.
文摘Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.
基金This research was supported by the National Natural Science Foundation of China(42001067)the Natural Science Foundation of Gansu Province(21JR7RA059)+3 种基金the National Cryosphere Desert Data Center(20D03)the State Key Laboratory of Cryospheric Science(SKLCS-ZZ-2021)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0201)the National Natural Science Foundation of China(41771077).
文摘Hanging glaciers hold the absolute dominant number in West China and their changes had important influences on local hydrology,sea-level rise and natural hazards(snow/ice avalanches).However,logistic and operational difficulties have resulted in the lack of in-situ-measured data,leaving us with poor knowledge of the changing behaviors of this type of glacier.Here,we presented the spatiotemporal pattern of seasonal and annual mass changes of a mid-latitude hanging glacier in the Tien Shan based on repeated terrestrial laser scanning(TLS)surveys during the period 2016-2018.The distributed glacier surface elevation changes exhibited highly spatiotemporal variability,and the winter elevation changes showed slight surface lowering at the upper elevations and weak thickening at the glacier terminus,which was contrary to altitudinal elevation changing patterns at the summer and annual scales.Mass balance processes of the hanging glacier mainly occurred during summer and the winter mass balance was nearly balanced(-0.10±0.15 m w.e.).The glacier exhibited more rapid mass loss than adjacent other morphological glacier and the estimated response time of the glacier to climate change was very short(6-9 years),indicating hanging glaciers will experience rapid wastage and disappearance in the future even with climate change mitigation.
