Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment impro...Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment improvement in winter was investigated by carrying out field experiments in Heqingyuan residential area in Beijing,and after that,numerical simulation with SPOTE(simulation platform for outdoor thermal environment) experiments for outdoor thermal environment of vegetation was adopted for comparison.The conclusions were summarized as follows:1) By comparing the experimental data with simulation results,it could be concluded that the wind field simulated was consistent with the actual wind field,and the flow distribution impacted by vegetation could be accurately reflected;2) The wind velocity with vegetation was lower than that without vegetation,and the wind velocity was reduced by 46%;3) By adjusting arrangement and types of vegetation in the regions with excessively large wind velocity,the pedestrian-level wind velocity could be obviously improved through the simulation and comparison.展开更多
The present study was conducted to evaluate minimally invasive tube cystostomy technique in goats and calves suffering from obstructive urolithiasis having intact and ruptured urinary bladder. This clinical study was ...The present study was conducted to evaluate minimally invasive tube cystostomy technique in goats and calves suffering from obstructive urolithiasis having intact and ruptured urinary bladder. This clinical study was carried out on 84 clinical cases （61 goats and 23 calves） based on the history, clinical signs and physical examination along with common laboratory techniques at the Chittagong Veterinary and Animal Sciences University during January 2015-December 2016. Physical parameters like heart rate, respiratory rate, rectal temperature and dehydration status of animals were noted and corrected abnormality before surgery. Some cases had slightly higher haemoglobin （Hb）, packed cell volume （PCV） and uric acid and epithelial casts in urine. The study revealed that abnormal calcium-phosphorus ratio was predisposing the animals to urolithiasis. It was found that young ruminants （3-5 months） were most commonly affected in both species. All affected animals were male in this study, in which calves were not castrated but in goats 95.08% animals were castrated. Rupture of bladder was more common in calves as compared to goats. Postoperatively all cases were administered with broad-spectrum antibiotic, anti-inflammatory agent and caliculolytic agents like ammonium chloride. Tube cystostomy with Foley’s catheter was the most satisfactory technique for the management of obstructive urolithiasis in small ruminants. Postoperative complications were recorded only in four animals and remaining 80 animals had a normal recovery from tube cystostomy. Tube cystostomy is a simple, inexpensive and very effective procedure for the treatment of urolithiasis in ruminants.展开更多
C. piaropi （Cercospora piaropi） and A. zonatum （Acremonium zonatum） have proved to be effective in reducing water hyacinth growth. However, efficacy of these fungi in field is limited by the effect of solar UV （u...C. piaropi （Cercospora piaropi） and A. zonatum （Acremonium zonatum） have proved to be effective in reducing water hyacinth growth. However, efficacy of these fungi in field is limited by the effect of solar UV （ultraviolet） light and desiccation. In this study, three compounds used as sunscreens and one seed plant that produce mucilage were tested for their effects on the infection produced by C. piaropi and A. zonatum inoculum under laboratory and field conditions. In laboratory conditions, TiO2 （titanium dioxide） and metamucil did not inhibit C. piaropi and A. zonatum viability. Moreover, the addition of TiO2 and metamucil to the inoculum suspension increased fungi infection. The protective effect of TiO2 and metamucil was more evident when the inoculum suspension was applied 4 h before sunset. These results suggest that addition of TiO2 and metamucil provides necessary humidity and solar protection for increasing C piaropi and A. zonatum infection on water hyacinth plants.展开更多
The researches were carried out in 2007, 2008 and 2009 at Cluj-Napoca （Romania）, in laboratory and field conditions （grassland ecosystems）, in four experiments. Our purpose was to study and use some ecological pes...The researches were carried out in 2007, 2008 and 2009 at Cluj-Napoca （Romania）, in laboratory and field conditions （grassland ecosystems）, in four experiments. Our purpose was to study and use some ecological pest control methods based on indirect and direct strategies： （1） the harmful fauna monitoring in grassland ecosystems and useful fauna identification （by visual control, manually collecting, striking method on a tarpaulin）; （2） the use of some physico-mechanical and biotechnical methods （use of barriers-vessels, repellents, attractant traps-alimentary, visual） to control the pests. The researches concerning the indirect strategies, carried out from Mars 2007 to September 2009. There were identified 28 pest species and 29 useful ones. The direct strategies to control the pests consisted of 3 experiments. The use of colored traps with water （August 2008） on a meadow with ryegrass and clover, in 6 variants （white, silver, orange, green, blue and red） ＋ control （yellow）, recorded a very good efficacy at all variants excepting the red trap （variant 6）. The use of repellents （August 2008）, absinth decoction （against aphids and ants）, bracken extract （against aphids and snails）, common tansy decoction （against ants and soil pests） and kaolinite （against a large amount of pests）, recorded good results removing the pests. The attractant traps with alimentary baits （beer）, meant the use of 10 vessels on a 1000 m2 area, which captured 200 slugs （August 2009）. All three methods recorded a good efficacy against the pests.展开更多
该文提出了1种半透明光伏窗太阳得热系数(Solar heat gain coefficient,SHGC)的简易室外测试方法。首先通过室外实验研究了不同运行状态下半透明光伏窗的SHGC,实验结果表明,光伏窗开路(Open circuit,OC)状态下的SHGC显著高于最大功率点(...该文提出了1种半透明光伏窗太阳得热系数(Solar heat gain coefficient,SHGC)的简易室外测试方法。首先通过室外实验研究了不同运行状态下半透明光伏窗的SHGC,实验结果表明,光伏窗开路(Open circuit,OC)状态下的SHGC显著高于最大功率点(Maximum power point,MPP)状态下的SHGC,两者的SHGC差异最高可达11.5%;其次,通过理论分析研究了电池覆盖率对不同运行状态下光伏窗SHGC的影响,同时探究了不同类型光伏窗在上述2种运行状态下的SHGC差异。该文的分析结果将为更准确地评价光伏窗的热工性能和空调负荷计算提供指导,并推动光伏建筑一体化技术发展。展开更多
The modal analysis of piping system in air conditioner (AC) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model f...The modal analysis of piping system in air conditioner (AC) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model for vibration behaviour prediction, the AC piping elastic end support characterization has been explored. The axial and radial stiffness variables (ka, kr1, kr2) of the compressor-piping mounting are obtained and represented by dynamic stiffness of compressor grommet. They are obtained from dynamic load deflection test based on compressor operating condition such as excitation frequency and amplitude. The unknown stiffness variables of the other tube end (chassis-piping mounting) are determined by parameter fine tuning. An experimental modal analysis using impact hammer test has also been employed to determine the vibration properties such as natural frequencies, mode shapes and damping ratio of the piping structures. The modal parameters acquisition using SCADAS mobile acquisition system and LMS Impact Testing software is compared with the corresponding simulated modal properties using Abaqus. Most of the simulated natural frequencies achieve good correlation with the measured frequencies and it is reasonably a good prediction model to predict vibration behaviour of AC piping structures.展开更多
基金Project(50878111) supported by the National Natural Science Foundation of China
文摘Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment improvement in winter was investigated by carrying out field experiments in Heqingyuan residential area in Beijing,and after that,numerical simulation with SPOTE(simulation platform for outdoor thermal environment) experiments for outdoor thermal environment of vegetation was adopted for comparison.The conclusions were summarized as follows:1) By comparing the experimental data with simulation results,it could be concluded that the wind field simulated was consistent with the actual wind field,and the flow distribution impacted by vegetation could be accurately reflected;2) The wind velocity with vegetation was lower than that without vegetation,and the wind velocity was reduced by 46%;3) By adjusting arrangement and types of vegetation in the regions with excessively large wind velocity,the pedestrian-level wind velocity could be obviously improved through the simulation and comparison.
文摘The present study was conducted to evaluate minimally invasive tube cystostomy technique in goats and calves suffering from obstructive urolithiasis having intact and ruptured urinary bladder. This clinical study was carried out on 84 clinical cases （61 goats and 23 calves） based on the history, clinical signs and physical examination along with common laboratory techniques at the Chittagong Veterinary and Animal Sciences University during January 2015-December 2016. Physical parameters like heart rate, respiratory rate, rectal temperature and dehydration status of animals were noted and corrected abnormality before surgery. Some cases had slightly higher haemoglobin （Hb）, packed cell volume （PCV） and uric acid and epithelial casts in urine. The study revealed that abnormal calcium-phosphorus ratio was predisposing the animals to urolithiasis. It was found that young ruminants （3-5 months） were most commonly affected in both species. All affected animals were male in this study, in which calves were not castrated but in goats 95.08% animals were castrated. Rupture of bladder was more common in calves as compared to goats. Postoperatively all cases were administered with broad-spectrum antibiotic, anti-inflammatory agent and caliculolytic agents like ammonium chloride. Tube cystostomy with Foley’s catheter was the most satisfactory technique for the management of obstructive urolithiasis in small ruminants. Postoperative complications were recorded only in four animals and remaining 80 animals had a normal recovery from tube cystostomy. Tube cystostomy is a simple, inexpensive and very effective procedure for the treatment of urolithiasis in ruminants.
文摘C. piaropi （Cercospora piaropi） and A. zonatum （Acremonium zonatum） have proved to be effective in reducing water hyacinth growth. However, efficacy of these fungi in field is limited by the effect of solar UV （ultraviolet） light and desiccation. In this study, three compounds used as sunscreens and one seed plant that produce mucilage were tested for their effects on the infection produced by C. piaropi and A. zonatum inoculum under laboratory and field conditions. In laboratory conditions, TiO2 （titanium dioxide） and metamucil did not inhibit C. piaropi and A. zonatum viability. Moreover, the addition of TiO2 and metamucil to the inoculum suspension increased fungi infection. The protective effect of TiO2 and metamucil was more evident when the inoculum suspension was applied 4 h before sunset. These results suggest that addition of TiO2 and metamucil provides necessary humidity and solar protection for increasing C piaropi and A. zonatum infection on water hyacinth plants.
文摘The researches were carried out in 2007, 2008 and 2009 at Cluj-Napoca （Romania）, in laboratory and field conditions （grassland ecosystems）, in four experiments. Our purpose was to study and use some ecological pest control methods based on indirect and direct strategies： （1） the harmful fauna monitoring in grassland ecosystems and useful fauna identification （by visual control, manually collecting, striking method on a tarpaulin）; （2） the use of some physico-mechanical and biotechnical methods （use of barriers-vessels, repellents, attractant traps-alimentary, visual） to control the pests. The researches concerning the indirect strategies, carried out from Mars 2007 to September 2009. There were identified 28 pest species and 29 useful ones. The direct strategies to control the pests consisted of 3 experiments. The use of colored traps with water （August 2008） on a meadow with ryegrass and clover, in 6 variants （white, silver, orange, green, blue and red） ＋ control （yellow）, recorded a very good efficacy at all variants excepting the red trap （variant 6）. The use of repellents （August 2008）, absinth decoction （against aphids and ants）, bracken extract （against aphids and snails）, common tansy decoction （against ants and soil pests） and kaolinite （against a large amount of pests）, recorded good results removing the pests. The attractant traps with alimentary baits （beer）, meant the use of 10 vessels on a 1000 m2 area, which captured 200 slugs （August 2009）. All three methods recorded a good efficacy against the pests.
文摘该文提出了1种半透明光伏窗太阳得热系数(Solar heat gain coefficient,SHGC)的简易室外测试方法。首先通过室外实验研究了不同运行状态下半透明光伏窗的SHGC,实验结果表明,光伏窗开路(Open circuit,OC)状态下的SHGC显著高于最大功率点(Maximum power point,MPP)状态下的SHGC,两者的SHGC差异最高可达11.5%;其次,通过理论分析研究了电池覆盖率对不同运行状态下光伏窗SHGC的影响,同时探究了不同类型光伏窗在上述2种运行状态下的SHGC差异。该文的分析结果将为更准确地评价光伏窗的热工性能和空调负荷计算提供指导,并推动光伏建筑一体化技术发展。
文摘The modal analysis of piping system in air conditioner (AC) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model for vibration behaviour prediction, the AC piping elastic end support characterization has been explored. The axial and radial stiffness variables (ka, kr1, kr2) of the compressor-piping mounting are obtained and represented by dynamic stiffness of compressor grommet. They are obtained from dynamic load deflection test based on compressor operating condition such as excitation frequency and amplitude. The unknown stiffness variables of the other tube end (chassis-piping mounting) are determined by parameter fine tuning. An experimental modal analysis using impact hammer test has also been employed to determine the vibration properties such as natural frequencies, mode shapes and damping ratio of the piping structures. The modal parameters acquisition using SCADAS mobile acquisition system and LMS Impact Testing software is compared with the corresponding simulated modal properties using Abaqus. Most of the simulated natural frequencies achieve good correlation with the measured frequencies and it is reasonably a good prediction model to predict vibration behaviour of AC piping structures.
