This paper will present several passive-cooling technologies and design features that can be adopted to reduce building heat gain without the need of excess energy consumption. A typical residential unit will be selec...This paper will present several passive-cooling technologies and design features that can be adopted to reduce building heat gain without the need of excess energy consumption. A typical residential unit will be selected as case study and a three basic passive cooling strategies were selected to enhance the building envelop, as well as using appropriate shading devices and green roofing system that prove to be a good environment quality improver. IES energy simulation software will be used to evaluate the performance of the building. The study revealed a number of significant findings in reducing the energy consumption and enhancing the tenants＇ thermal comfort. American Society of Heating Refrigerating and Airconditioning Engineer （ASHRAE） standards specially via improving the performance of building envelop because it is the interface between internal and external environment. Moreover, improving the building envelope has recorded that overall energy and chiller energy consumption can be reduced up to 10.8% and 21.6% respectively, Therefore, it is anticipated that further reductions can be achieved via applying more passive cooling strategies. Finally, it could argue that the results of this paper will not only be applicable to Bahrain but also many countries that have similar climatic and environmental context.展开更多
Photocatalytic activity of TiO2 nanopowders of anatase modification with various particle sizes and specific surface areas has been studied in the process of photocatalytic decolorization of aqueous solutions of methy...Photocatalytic activity of TiO2 nanopowders of anatase modification with various particle sizes and specific surface areas has been studied in the process of photocatalytic decolorization of aqueous solutions of methylene blue and direct blue 2C azodyes. By means of scanning electron microscopy and low-temperature N2 adsorption method, it was found that TiO2 nanopowders have the particles size of 5-120 nm with the specific surface area of 15-120 m2·g^-1. The used TiO2 samples are characterized by mesoporous structures with average pore size of 4.3-14.9 nm. The photocatalytic activity of TiO2 was evaluated via decolorization of azodyes solutions. It was shown that the efficiency of decolorization symbatically changes with the dye adsorption value on TiO2 surface and the degree of decolorization rises when the surface area of TiO2 nanopowders increases. It was found that TiO2 photocatalytic activity essentially depends on adsorption interactions between the dye molecules and catalytic active centers on TiO2 surface, and these interactions, in turn, are greatly affected by pH of the solution.展开更多
To investigate the effect of moderate hypothermia on respon ses of axonal cytoskeleton to axonal injury in the acute stage of injury. Methods: Of fifteen adult guinea pigs, twelve animals were subj ected to stretch in...To investigate the effect of moderate hypothermia on respon ses of axonal cytoskeleton to axonal injury in the acute stage of injury. Methods: Of fifteen adult guinea pigs, twelve animals were subj ected to stretch injury to the right optic nerves and divided into the normother mic group (n=6) in which the animals core temperature was maintained at 36.0 37.5℃ and the hypothermia group (n=6) in which the core temperature was red uced to 32.0 32.5℃ after stretch injury. Remaining three animals sustained no injury to the right optic nerves and served as control group. Half of injure d animals (n=3) of either normothermic group or hypothermic group were killed at either 2 hours or 4 hours after injury. The ultrastructural changes of axonal c ytoskeleton of the right optic nerve fibers from the animals were examined under a transmission electron microscope and analyzed by quantitative analysis with a computer image analysis system. Results: At 2 hours after stretch injury, there was a significa nt reduction in the mean number of microtubules (P< 0.001 ), and a significant increase in the mean intermicrotubule spacing (P< 0.05 or P< 0.01 ) in axons of all siz es in normothermic animals. The mean number of neurofilaments also decreased sta tistically (P< 0.01 ) in large and medium subgroups of a xons in the same experimental group at 2 hours. By 4 hours, the large subgroup o f axons in normothermic animals still demonstrated a significant decline in the mean number of microtubules (P< 0.01 ) and an increase i n the mean intermicrotubule spacing (P< 0.05 ), while th e medium and small subgroups of axons displayed a significant increase in the me an number of neurofilaments (P< 0.05 ) and reduction in the mean interneurofilament spacing (P< 0.05 ). On the c ontrary, either the mean number of microtubules and the mean intermicrotubule sp acing, or the mean number of neurofilaments and interneurofilament spacing in ax ons of all sizes in hypothermic stretch injured animals was not significant dif ferent from the mean values of sham operated animals. Conclusions: Posttraumatic moderate hypothermia induced immedia tely after axonal injury results in substantial protection of axonal cytoskeleto n and ameliorates axonal damage.展开更多
In this paper,we carried out a series of experiments on fouling characteristics of 6 kinds of spiral-grooved tubes to investigate the impact of hardness,temperature and structure parameters of cold water on fouling ch...In this paper,we carried out a series of experiments on fouling characteristics of 6 kinds of spiral-grooved tubes to investigate the impact of hardness,temperature and structure parameters of cold water on fouling characteristics of spiral-grooved tube.Experimental results showed that when cold-water temperature decreased,fouling resistance of spiral-grooved tube also decreased.Asymptotic fouling resistance increased accompanied with increase of cold-water hardness.However,the asymptotic fouling resistance appeared to reduce when hardness increased to some extent.Geometric parameters of spiral-grooved tubes had remarkable effect on fouling resistance,which showed a tendency of decrease with increase of groove depth and decrease of pitch.In this study,the minimum asymptotic fouling resistance was observed in the spiral-grooved tube with small pitch and large groove depth.展开更多
文摘This paper will present several passive-cooling technologies and design features that can be adopted to reduce building heat gain without the need of excess energy consumption. A typical residential unit will be selected as case study and a three basic passive cooling strategies were selected to enhance the building envelop, as well as using appropriate shading devices and green roofing system that prove to be a good environment quality improver. IES energy simulation software will be used to evaluate the performance of the building. The study revealed a number of significant findings in reducing the energy consumption and enhancing the tenants＇ thermal comfort. American Society of Heating Refrigerating and Airconditioning Engineer （ASHRAE） standards specially via improving the performance of building envelop because it is the interface between internal and external environment. Moreover, improving the building envelope has recorded that overall energy and chiller energy consumption can be reduced up to 10.8% and 21.6% respectively, Therefore, it is anticipated that further reductions can be achieved via applying more passive cooling strategies. Finally, it could argue that the results of this paper will not only be applicable to Bahrain but also many countries that have similar climatic and environmental context.
文摘Photocatalytic activity of TiO2 nanopowders of anatase modification with various particle sizes and specific surface areas has been studied in the process of photocatalytic decolorization of aqueous solutions of methylene blue and direct blue 2C azodyes. By means of scanning electron microscopy and low-temperature N2 adsorption method, it was found that TiO2 nanopowders have the particles size of 5-120 nm with the specific surface area of 15-120 m2·g^-1. The used TiO2 samples are characterized by mesoporous structures with average pore size of 4.3-14.9 nm. The photocatalytic activity of TiO2 was evaluated via decolorization of azodyes solutions. It was shown that the efficiency of decolorization symbatically changes with the dye adsorption value on TiO2 surface and the degree of decolorization rises when the surface area of TiO2 nanopowders increases. It was found that TiO2 photocatalytic activity essentially depends on adsorption interactions between the dye molecules and catalytic active centers on TiO2 surface, and these interactions, in turn, are greatly affected by pH of the solution.
文摘To investigate the effect of moderate hypothermia on respon ses of axonal cytoskeleton to axonal injury in the acute stage of injury. Methods: Of fifteen adult guinea pigs, twelve animals were subj ected to stretch injury to the right optic nerves and divided into the normother mic group (n=6) in which the animals core temperature was maintained at 36.0 37.5℃ and the hypothermia group (n=6) in which the core temperature was red uced to 32.0 32.5℃ after stretch injury. Remaining three animals sustained no injury to the right optic nerves and served as control group. Half of injure d animals (n=3) of either normothermic group or hypothermic group were killed at either 2 hours or 4 hours after injury. The ultrastructural changes of axonal c ytoskeleton of the right optic nerve fibers from the animals were examined under a transmission electron microscope and analyzed by quantitative analysis with a computer image analysis system. Results: At 2 hours after stretch injury, there was a significa nt reduction in the mean number of microtubules (P< 0.001 ), and a significant increase in the mean intermicrotubule spacing (P< 0.05 or P< 0.01 ) in axons of all siz es in normothermic animals. The mean number of neurofilaments also decreased sta tistically (P< 0.01 ) in large and medium subgroups of a xons in the same experimental group at 2 hours. By 4 hours, the large subgroup o f axons in normothermic animals still demonstrated a significant decline in the mean number of microtubules (P< 0.01 ) and an increase i n the mean intermicrotubule spacing (P< 0.05 ), while th e medium and small subgroups of axons displayed a significant increase in the me an number of neurofilaments (P< 0.05 ) and reduction in the mean interneurofilament spacing (P< 0.05 ). On the c ontrary, either the mean number of microtubules and the mean intermicrotubule sp acing, or the mean number of neurofilaments and interneurofilament spacing in ax ons of all sizes in hypothermic stretch injured animals was not significant dif ferent from the mean values of sham operated animals. Conclusions: Posttraumatic moderate hypothermia induced immedia tely after axonal injury results in substantial protection of axonal cytoskeleto n and ameliorates axonal damage.
基金supported by the Special Funds for Major State Basic Research Projects of China ("973" Program) (Grant No. 2007CB206904)
文摘In this paper,we carried out a series of experiments on fouling characteristics of 6 kinds of spiral-grooved tubes to investigate the impact of hardness,temperature and structure parameters of cold water on fouling characteristics of spiral-grooved tube.Experimental results showed that when cold-water temperature decreased,fouling resistance of spiral-grooved tube also decreased.Asymptotic fouling resistance increased accompanied with increase of cold-water hardness.However,the asymptotic fouling resistance appeared to reduce when hardness increased to some extent.Geometric parameters of spiral-grooved tubes had remarkable effect on fouling resistance,which showed a tendency of decrease with increase of groove depth and decrease of pitch.In this study,the minimum asymptotic fouling resistance was observed in the spiral-grooved tube with small pitch and large groove depth.
