Micromixing efficiency of viscous media in Y-type micro-channel reactor was studied by using iodide-iodate test reaction as working system.Experiments were carried out in water-glycerin mixtures with 7 different visco...Micromixing efficiency of viscous media in Y-type micro-channel reactor was studied by using iodide-iodate test reaction as working system.Experiments were carried out in water-glycerin mixtures with 7 different viscosities.The experimental results showed that segregation index of the micro-channel reactor increases with the decrease of volumetric flow rate and the increase of solution viscosity.Based on the incorporation model,the micromixing time tm of the micro-channel reactor was estimated in the range of 10-4-10-3s at different viscosities,which indicated that the micro-channel reactor possesses a much better micromixing performance compared to the stirred tank(tm=0.02-0.2s).展开更多
In 2012, an infestation of Asian Longhomed Beetle （ALB） was detected in Winterthur （Canton Zurich, Switzerland）. With more than 140 adult beetles and several hundred eggs and larvae, the infestation was by far the...In 2012, an infestation of Asian Longhomed Beetle （ALB） was detected in Winterthur （Canton Zurich, Switzerland）. With more than 140 adult beetles and several hundred eggs and larvae, the infestation was by far the most extensive in Switzerland. Based on long-term experiences made in Braunau （Austria）, where the first ALB infestation in Europe occured, the beetle was fought with extensive actions： removal of all infested trees, preventive removal of potential host trees and installation of a focus- and a buffer zone. Transport of plant material out of these zones was banned and a close monitoring regime including specialised dogs put in place. As a result of these efforts, there were no adult beetles and only a few living larvae detected 2013. Neither larvae nor beetles were found in 2014. However, costs are high： 700,000 Swiss francs were spent in 2012 alone, not including hundreds of working hours spent by employees of the Canton Zurich. The previewed monitoring programme between 2013 and 2017 is estimated to cost another 2.8 million Swiss francs, if no more living beetles are detected. The experiences from Winterthur thus show that elimination of a relatively small ALB infestation with determined actions is likely possible in short time. However, the high costs demonstrate the need for strong boarder controls or alternative packaging materials for imports from infested regions （China）. In addition, a concept for small communities with limited resources is needed.展开更多
Development of gas turbine oils that can be used in higher temperature conditions remains the greatest technological challenge. Though the maximum operating temperature of conventional lubricating oils is generally se...Development of gas turbine oils that can be used in higher temperature conditions remains the greatest technological challenge. Though the maximum operating temperature of conventional lubricating oils is generally set around 100 ℃, or 140 ℃ for scavenged oils, it is predicted that the future will require oils to function at 200 ℃ or above. To find a clue to developing oils that can be used at higher temperatures, this study attempted to estimate service lives and operating temperature ranges of certain oils, including oils conforming to MIL-PRF-23699, which are deemed promising candidates for high-temperature applications, by analyzing their reaction rates of degradation and degeneration by oxidation. Among a number of methods used in the analyses of reaction rates, this study chose thermo-gravimetry （TG）, with which estimations can be made relatively easily.展开更多
In this article, the authors give an overview of different logistics concepts for operation and maintenance of OWPP （offshore wind power plants）. These can be generally classified into onshore based and offshore bas...In this article, the authors give an overview of different logistics concepts for operation and maintenance of OWPP （offshore wind power plants）. These can be generally classified into onshore based and offshore based concepts. The operation of OWPPs can still be improved as research has shown that the availability of OWPPs is low compared to onshore wind power plants. There are a few tools to calculate operating costs and to evaluate the different concepts. However, most tools have a weak focus on logistics although logistics account for a big share of the costs. The tool the authors are introducing in this article focuses on the logistics processes. It is first explained and then tested with an OWPP scenarin展开更多
基金Supported by the National-Natural Science Foundation of China （20821004, 20806004） and the National High Technology Research and Development Program of China （2007AA030207, 2006AA030202, 2006AA030203）.
文摘Micromixing efficiency of viscous media in Y-type micro-channel reactor was studied by using iodide-iodate test reaction as working system.Experiments were carried out in water-glycerin mixtures with 7 different viscosities.The experimental results showed that segregation index of the micro-channel reactor increases with the decrease of volumetric flow rate and the increase of solution viscosity.Based on the incorporation model,the micromixing time tm of the micro-channel reactor was estimated in the range of 10-4-10-3s at different viscosities,which indicated that the micro-channel reactor possesses a much better micromixing performance compared to the stirred tank(tm=0.02-0.2s).
文摘In 2012, an infestation of Asian Longhomed Beetle （ALB） was detected in Winterthur （Canton Zurich, Switzerland）. With more than 140 adult beetles and several hundred eggs and larvae, the infestation was by far the most extensive in Switzerland. Based on long-term experiences made in Braunau （Austria）, where the first ALB infestation in Europe occured, the beetle was fought with extensive actions： removal of all infested trees, preventive removal of potential host trees and installation of a focus- and a buffer zone. Transport of plant material out of these zones was banned and a close monitoring regime including specialised dogs put in place. As a result of these efforts, there were no adult beetles and only a few living larvae detected 2013. Neither larvae nor beetles were found in 2014. However, costs are high： 700,000 Swiss francs were spent in 2012 alone, not including hundreds of working hours spent by employees of the Canton Zurich. The previewed monitoring programme between 2013 and 2017 is estimated to cost another 2.8 million Swiss francs, if no more living beetles are detected. The experiences from Winterthur thus show that elimination of a relatively small ALB infestation with determined actions is likely possible in short time. However, the high costs demonstrate the need for strong boarder controls or alternative packaging materials for imports from infested regions （China）. In addition, a concept for small communities with limited resources is needed.
文摘Development of gas turbine oils that can be used in higher temperature conditions remains the greatest technological challenge. Though the maximum operating temperature of conventional lubricating oils is generally set around 100 ℃, or 140 ℃ for scavenged oils, it is predicted that the future will require oils to function at 200 ℃ or above. To find a clue to developing oils that can be used at higher temperatures, this study attempted to estimate service lives and operating temperature ranges of certain oils, including oils conforming to MIL-PRF-23699, which are deemed promising candidates for high-temperature applications, by analyzing their reaction rates of degradation and degeneration by oxidation. Among a number of methods used in the analyses of reaction rates, this study chose thermo-gravimetry （TG）, with which estimations can be made relatively easily.
文摘In this article, the authors give an overview of different logistics concepts for operation and maintenance of OWPP （offshore wind power plants）. These can be generally classified into onshore based and offshore based concepts. The operation of OWPPs can still be improved as research has shown that the availability of OWPPs is low compared to onshore wind power plants. There are a few tools to calculate operating costs and to evaluate the different concepts. However, most tools have a weak focus on logistics although logistics account for a big share of the costs. The tool the authors are introducing in this article focuses on the logistics processes. It is first explained and then tested with an OWPP scenarin
