Gas transport mechanisms can be categorized into viscous flow and mass diffusion,both of which may coexist in a porous media with multiscale pore sizes.To determine the dominant transport mechanism and its contributio...Gas transport mechanisms can be categorized into viscous flow and mass diffusion,both of which may coexist in a porous media with multiscale pore sizes.To determine the dominant transport mechanism and its contribution to gas transport capacity,the gas viscous flow and mass diffusion processes are analyzed in single nanoscale pores via a theoretical method,and are simulated in 3D nanoporous media via pore-scale lattice Boltzmann methods.The apparent permeability from the viscous flow and apparent diffusivity from the mass diffusion are estimated.A dimensionless parameter,i.e.,the diffusion-flow ratio,is proposed to evaluate the dominant transport mechanism,which is a function of the apparent permeability,apparent diffusivity,bulk dynamic viscosity,and working pressure.The results show that the apparent permeability increases by approximately two orders of magnitude when the average Knudsen number(Kn_(avg))of the nanoporous media or Knudsen number(Kn)of single nanoscale pores increases from 0.1 to 10.Under the same conditions,the increment in the apparent diffusivity is only approximately one order of magnitude.When Kn<0.01,the apparent permeability has a lower bound(i.e.,absolute permeability).When Kn>10,the apparent diffusivity has an upper bound(i.e.,Knudsen diffusivity).The dominant transport mechanism in single nanoscale pores is the viscous flow for 0.01<Kn<100,where the maximum diffusion-flow ratio is less than one.In nanoporous media,the dominant transport relies heavily on Kn_(avg) and the structural parameters.For nanoporous media with the pore throat diameter of 3 nm,Kn_(avg)=0.2 is the critical point,above which the mass diffusion is dominant;otherwise,the viscous flow is dominant.As Kn_(avg) increases to 3.4,the mass diffusion is overwhelming,with the maximum diffusion-flow ratio reaching ~4.展开更多
Selective targeting of drugs to the proposed site of action provides therapeutic advantages such as reduced toxicity and smaller dose levels. Despite a huge progress made in drug design and delivery systems, many chal...Selective targeting of drugs to the proposed site of action provides therapeutic advantages such as reduced toxicity and smaller dose levels. Despite a huge progress made in drug design and delivery systems, many challenges still have to be solved. Small therapeutic drugs always have the potential to pass into the kidneys and be excreted from the body. The use of macromolecular constructs (carriers) that allow longer circulation times, contribute to improved chemical functionality and more precise drug delivery is an attractive alternative option. Bioadhesive systems which will utilize intense contact to increase the drug concentration gradient could be an attractive approach. Because of their specific carbohydrate-binding, lectins can interact with glycoconjugates present on the epithelial cells that line all of the organs exposed to the external environment. The unique carbohydrate specificities of plant lectins can facilitate mucoadhesion and cytoadhesion of drugs. As immunostimulatory molecules with an adjuvant effect plant lectins can also be employed in vaccine development.展开更多
Overabundant and unbalanced input of nutritional elements to soil has a negative effect to the yield and quality of lettuce. Accumulation of nitrates and harmful effects of the chloride ion are the reasons why there i...Overabundant and unbalanced input of nutritional elements to soil has a negative effect to the yield and quality of lettuce. Accumulation of nitrates and harmful effects of the chloride ion are the reasons why there is a need to establish an optimal quantity and relation of nutrients in lettuce nourishment. In the experiment which was carried out during years 2010 and 2011 on the farm of Secondary Agricultural Boarding School in Futog, nitrate content in a fresh mass of lettuce （mg NO3/kg） was obesrved, in dependence on applied compound fertilizers produced by different technologies at different quantities of nitrate and potassium fertilizers. The results of the research show that in a technological ripeness, the highest average lettuce yield has been obtained in the treatment where the highest dosage of nitrate fertilizers was used in spring, in a combination with complex fertilizers in autumn. The lowest average yield has been obtained on the control plot. The highest average nitrate concentration in a fresh lettuce mass has been recorded in using technology of applying mixed fertilizers and the smallest in using a technology of complex fertilizers. At the moment of harvest, the highest nitrogen content in a dry mass of a plant has been recorded when complex fertilizers of phosphorus and potassium were used by the technology of mixed fertilizers.展开更多
In recent years, the energy sector has undergone an important transformation as a result of technological progress and socio-economic development. The continuous integration of renewable energy sources forces a gradua...In recent years, the energy sector has undergone an important transformation as a result of technological progress and socio-economic development. The continuous integration of renewable energy sources forces a gradual transition from the traditional business model based on a reduced number of large power plants to a more decentralized energy production. The decentralization and the increased number of energy sources lead to a series of new challenges in the energy sector. This paper presents an approach to determine the optimal energy supply mix for small and medium sized buildings or installations. The optimization algorithm considers the electricity and heat demand and determines the optimal combination of energy sources by minimizing an economic index. The optimization problem can be solved for multiple demand profiles and takes into account the possibility to integrate accumulator systems. The proposed approach provides a high degree of flexibility and can be used to study the influence of the energy prices on the optimal energy supply mix. The performance of the proposed optimization approach is illustrated by the results obtained from a simulation example.展开更多
The anisotropic absorption and emission from semiconductor CdSe/CdS quantum rods(QRs)provide extra benefits among other photoluminescence nanocrystals.Using photo-induced alignment technique,the QRs can be oriented in...The anisotropic absorption and emission from semiconductor CdSe/CdS quantum rods(QRs)provide extra benefits among other photoluminescence nanocrystals.Using photo-induced alignment technique,the QRs can be oriented in liquid crystal polymer matrix at a large scale.In this article,a 2D Dammann grating pattern,within“SKL”characters domains aligned QRs in composite film,was fabricated by multi-step photo exposure using several photo masks,and a continuous geometric lens profile pattern aligned QRs was realized by the single step polarization converting holographic irradiation method.Both polarized optical microscope and fluorescence microscope are employed to determine the liquid crystal director profiles and QRs anisotropic excitation properties.We have been able to orient the QRs in fine binary and continuous patterns that confirms the strong quantum rod aligning ability of the proposed method.Thus,the proposed approach paves a way for photoinduced flexible QRs alignments to provide a highly specific and difficult-to-replicate security application at a large scale.展开更多
Unidirectionally aligned nanorods(NRs)are of great importance for different applications,including displays,lighting,and photodetectors.Recently,many alignment techniques were studied to align quantum rods(QRs).Howeve...Unidirectionally aligned nanorods(NRs)are of great importance for different applications,including displays,lighting,and photodetectors.Recently,many alignment techniques were studied to align quantum rods(QRs).However,the brightness of these films,due to the limited concentration of aligned quantum rods in the film,is not enough for their implementation as brightness enhancement films(BEFs)in displays.This can be ascribed to the poor miscibility of quantum rods in polymer and strong concentration dependence of the polarized emission.The ligands of NR are very important for the alignment and brightness.In this article,we proposed a ligand combination comprising T-shape promesogenic phosphonic acid,which on being photoaligned provides mutually parallel alignment of the quantum rods.The T-shape ligands enable the fabrication of hybrid films with a QRs concentration as high as 10 wt.%–20 wt.%retaining high brightness and luminescence polarization property.Later,we used these films in the in-plane switching(IPS)display backlight that shows the color gamut up to 121%of national television system committee(NTSC)(CIE1931),liquid-crystal display(LCD)efficiency up to 7.9%,power efficacy 103±2 nits/W,and the high brightness of~550±10 nits.Thus,the proposed ligands can be used for the alignment of a variety of nanorods.展开更多
基金supported by the National Science Foundation for Distinguished Young Scholars(52025065)the China Scholarship Council(201906280349)for its financial support during her study at The University of Texas at Austin.
文摘Gas transport mechanisms can be categorized into viscous flow and mass diffusion,both of which may coexist in a porous media with multiscale pore sizes.To determine the dominant transport mechanism and its contribution to gas transport capacity,the gas viscous flow and mass diffusion processes are analyzed in single nanoscale pores via a theoretical method,and are simulated in 3D nanoporous media via pore-scale lattice Boltzmann methods.The apparent permeability from the viscous flow and apparent diffusivity from the mass diffusion are estimated.A dimensionless parameter,i.e.,the diffusion-flow ratio,is proposed to evaluate the dominant transport mechanism,which is a function of the apparent permeability,apparent diffusivity,bulk dynamic viscosity,and working pressure.The results show that the apparent permeability increases by approximately two orders of magnitude when the average Knudsen number(Kn_(avg))of the nanoporous media or Knudsen number(Kn)of single nanoscale pores increases from 0.1 to 10.Under the same conditions,the increment in the apparent diffusivity is only approximately one order of magnitude.When Kn<0.01,the apparent permeability has a lower bound(i.e.,absolute permeability).When Kn>10,the apparent diffusivity has an upper bound(i.e.,Knudsen diffusivity).The dominant transport mechanism in single nanoscale pores is the viscous flow for 0.01<Kn<100,where the maximum diffusion-flow ratio is less than one.In nanoporous media,the dominant transport relies heavily on Kn_(avg) and the structural parameters.For nanoporous media with the pore throat diameter of 3 nm,Kn_(avg)=0.2 is the critical point,above which the mass diffusion is dominant;otherwise,the viscous flow is dominant.As Kn_(avg) increases to 3.4,the mass diffusion is overwhelming,with the maximum diffusion-flow ratio reaching ~4.
文摘Selective targeting of drugs to the proposed site of action provides therapeutic advantages such as reduced toxicity and smaller dose levels. Despite a huge progress made in drug design and delivery systems, many challenges still have to be solved. Small therapeutic drugs always have the potential to pass into the kidneys and be excreted from the body. The use of macromolecular constructs (carriers) that allow longer circulation times, contribute to improved chemical functionality and more precise drug delivery is an attractive alternative option. Bioadhesive systems which will utilize intense contact to increase the drug concentration gradient could be an attractive approach. Because of their specific carbohydrate-binding, lectins can interact with glycoconjugates present on the epithelial cells that line all of the organs exposed to the external environment. The unique carbohydrate specificities of plant lectins can facilitate mucoadhesion and cytoadhesion of drugs. As immunostimulatory molecules with an adjuvant effect plant lectins can also be employed in vaccine development.
文摘Overabundant and unbalanced input of nutritional elements to soil has a negative effect to the yield and quality of lettuce. Accumulation of nitrates and harmful effects of the chloride ion are the reasons why there is a need to establish an optimal quantity and relation of nutrients in lettuce nourishment. In the experiment which was carried out during years 2010 and 2011 on the farm of Secondary Agricultural Boarding School in Futog, nitrate content in a fresh mass of lettuce （mg NO3/kg） was obesrved, in dependence on applied compound fertilizers produced by different technologies at different quantities of nitrate and potassium fertilizers. The results of the research show that in a technological ripeness, the highest average lettuce yield has been obtained in the treatment where the highest dosage of nitrate fertilizers was used in spring, in a combination with complex fertilizers in autumn. The lowest average yield has been obtained on the control plot. The highest average nitrate concentration in a fresh lettuce mass has been recorded in using technology of applying mixed fertilizers and the smallest in using a technology of complex fertilizers. At the moment of harvest, the highest nitrogen content in a dry mass of a plant has been recorded when complex fertilizers of phosphorus and potassium were used by the technology of mixed fertilizers.
文摘In recent years, the energy sector has undergone an important transformation as a result of technological progress and socio-economic development. The continuous integration of renewable energy sources forces a gradual transition from the traditional business model based on a reduced number of large power plants to a more decentralized energy production. The decentralization and the increased number of energy sources lead to a series of new challenges in the energy sector. This paper presents an approach to determine the optimal energy supply mix for small and medium sized buildings or installations. The optimization algorithm considers the electricity and heat demand and determines the optimal combination of energy sources by minimizing an economic index. The optimization problem can be solved for multiple demand profiles and takes into account the possibility to integrate accumulator systems. The proposed approach provides a high degree of flexibility and can be used to study the influence of the energy prices on the optimal energy supply mix. The performance of the proposed optimization approach is illustrated by the results obtained from a simulation example.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030009)the National Natural Science Foundation of China(Nos.62005180,61935013)+2 种基金the Zhejiang Lab Open Research Project(No.K2022MG0AB01)RGC of Hong Kong S.A.R.(No.26202019)the State Key Laboratory of Advanced Displays and Optoelectronics Technologies(HKUST)(No.ITC-PSKL12EG02)。
文摘The anisotropic absorption and emission from semiconductor CdSe/CdS quantum rods(QRs)provide extra benefits among other photoluminescence nanocrystals.Using photo-induced alignment technique,the QRs can be oriented in liquid crystal polymer matrix at a large scale.In this article,a 2D Dammann grating pattern,within“SKL”characters domains aligned QRs in composite film,was fabricated by multi-step photo exposure using several photo masks,and a continuous geometric lens profile pattern aligned QRs was realized by the single step polarization converting holographic irradiation method.Both polarized optical microscope and fluorescence microscope are employed to determine the liquid crystal director profiles and QRs anisotropic excitation properties.We have been able to orient the QRs in fine binary and continuous patterns that confirms the strong quantum rod aligning ability of the proposed method.Thus,the proposed approach paves a way for photoinduced flexible QRs alignments to provide a highly specific and difficult-to-replicate security application at a large scale.
基金supported by the RGC of Hong Kong SAR,China(No.26202019)the funding for The State Key Laboratory of Advanced Displays and Optoelectronics Technologies.
文摘Unidirectionally aligned nanorods(NRs)are of great importance for different applications,including displays,lighting,and photodetectors.Recently,many alignment techniques were studied to align quantum rods(QRs).However,the brightness of these films,due to the limited concentration of aligned quantum rods in the film,is not enough for their implementation as brightness enhancement films(BEFs)in displays.This can be ascribed to the poor miscibility of quantum rods in polymer and strong concentration dependence of the polarized emission.The ligands of NR are very important for the alignment and brightness.In this article,we proposed a ligand combination comprising T-shape promesogenic phosphonic acid,which on being photoaligned provides mutually parallel alignment of the quantum rods.The T-shape ligands enable the fabrication of hybrid films with a QRs concentration as high as 10 wt.%–20 wt.%retaining high brightness and luminescence polarization property.Later,we used these films in the in-plane switching(IPS)display backlight that shows the color gamut up to 121%of national television system committee(NTSC)(CIE1931),liquid-crystal display(LCD)efficiency up to 7.9%,power efficacy 103±2 nits/W,and the high brightness of~550±10 nits.Thus,the proposed ligands can be used for the alignment of a variety of nanorods.
