One of the best ways to make progress with English is to read.Readind text in English can help students in many aspects of their learning.When they read in English they learn new words and grammar strucures.If the stu...One of the best ways to make progress with English is to read.Readind text in English can help students in many aspects of their learning.When they read in English they learn new words and grammar strucures.If the students repeatedly see that new vocabulary they’ll learn it by heart and then they’ll be able to use it when writing or speaking in English.展开更多
The electrification of building heating is an effective way to meet the global carbon target. As a clean and sustainable electrified heating technology, air-source heat pumps (ASHPs) are widely used in areas lacking c...The electrification of building heating is an effective way to meet the global carbon target. As a clean and sustainable electrified heating technology, air-source heat pumps (ASHPs) are widely used in areas lacking central heating. However, as a major component of space heating, heating terminals might not fit well with ASHP in order to achieve both intermittency and comfort. Therefore, this study proposes a novel radiation-adjustable heating terminal combined with an ASHP to achieve electrification, intermittency, and better thermal comfort. Radiant terminals currently suffer from three major problems: limited maximum heating capacity, inability to freely adapt, and difficulty with combining them with ASHPs. These problems were solved by improving the structural design of the novel terminal (Improvement A–E). Results showed that the maximum heating capacity increased by 23.6% and radiation heat transfer ratio from 10.1% to 30.9% was provided for users with the novel terminal. Further, new flat heat pipe (FHP) design improved stability (compressor oil return), intermittency (refrigerant thermal inertia), and safety (refrigerant leakage risk) by reducing the length of exposed refrigerant pipes. Furthermore, a new phased operation strategy was proposed for the novel terminal, and the adjustability of the terminal was improved. The results can be used as reference information for decarbonizing buildings by electrifying heating terminals.展开更多
Identification and enumeration of both dendritic Ia^+ epi-dermal cells (Ia^+DECs) and dendritic Thy-1^+ epidermalcells (Thy-1^+DECa) from various parts of the body wereexamined by using epidermal sheets of C3H/He inbr...Identification and enumeration of both dendritic Ia^+ epi-dermal cells (Ia^+DECs) and dendritic Thy-1^+ epidermalcells (Thy-1^+DECa) from various parts of the body wereexamined by using epidermal sheets of C3H/He inbred miceof different age groups and indirect immunofluorescent tech-nique. A significant decline of both Ia^+DECs and Thy-1^+DECs in the mice of the aged group was demonstrated anddifferent densities and different distribution patterns betweenIa^+DECs and Thy-1^+DECs were obserged. These findingsmay imply that the decline of both Ia^+DECs and Thy-1^+DECs in the aged group may reflect the alterations of im-mune response in aging.展开更多
With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw pl...With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut rock and weakly impr egnated diamonds in weakly impregnated layer make segment expose, then design a new type of layered segment for diamond saw plate.展开更多
文摘One of the best ways to make progress with English is to read.Readind text in English can help students in many aspects of their learning.When they read in English they learn new words and grammar strucures.If the students repeatedly see that new vocabulary they’ll learn it by heart and then they’ll be able to use it when writing or speaking in English.
基金supported by the National Science Foundation for Distinguished Young Scholars of China(51825802).
文摘The electrification of building heating is an effective way to meet the global carbon target. As a clean and sustainable electrified heating technology, air-source heat pumps (ASHPs) are widely used in areas lacking central heating. However, as a major component of space heating, heating terminals might not fit well with ASHP in order to achieve both intermittency and comfort. Therefore, this study proposes a novel radiation-adjustable heating terminal combined with an ASHP to achieve electrification, intermittency, and better thermal comfort. Radiant terminals currently suffer from three major problems: limited maximum heating capacity, inability to freely adapt, and difficulty with combining them with ASHPs. These problems were solved by improving the structural design of the novel terminal (Improvement A–E). Results showed that the maximum heating capacity increased by 23.6% and radiation heat transfer ratio from 10.1% to 30.9% was provided for users with the novel terminal. Further, new flat heat pipe (FHP) design improved stability (compressor oil return), intermittency (refrigerant thermal inertia), and safety (refrigerant leakage risk) by reducing the length of exposed refrigerant pipes. Furthermore, a new phased operation strategy was proposed for the novel terminal, and the adjustability of the terminal was improved. The results can be used as reference information for decarbonizing buildings by electrifying heating terminals.
文摘Identification and enumeration of both dendritic Ia^+ epi-dermal cells (Ia^+DECs) and dendritic Thy-1^+ epidermalcells (Thy-1^+DECa) from various parts of the body wereexamined by using epidermal sheets of C3H/He inbred miceof different age groups and indirect immunofluorescent tech-nique. A significant decline of both Ia^+DECs and Thy-1^+DECs in the mice of the aged group was demonstrated anddifferent densities and different distribution patterns betweenIa^+DECs and Thy-1^+DECs were obserged. These findingsmay imply that the decline of both Ia^+DECs and Thy-1^+DECs in the aged group may reflect the alterations of im-mune response in aging.
文摘With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut rock and weakly impr egnated diamonds in weakly impregnated layer make segment expose, then design a new type of layered segment for diamond saw plate.
