A two-layer implicit difference scheme is employed in the present study to determine the temperature distribution in an asphalt pavement.The calculation of each layer only needs four iterations to achieve convergence....A two-layer implicit difference scheme is employed in the present study to determine the temperature distribution in an asphalt pavement.The calculation of each layer only needs four iterations to achieve convergence.Furthermore,in order to improve the calculation accuracy a swarm intelligence optimization algorithm is also exploited to inversely analyze the laws by which the thermal physical parameters of the asphalt pavement materials change with temperature.Using the basic cuckoo and the gray wolf algorithms,an adaptive hybrid optimization algorithm is obtained and used to determine the relationship between the thermal diffusivity of two types of asphalt pavement materials and the temperature.As shown by the results,the prediction accuracy achievable with this approach is higher than that of the linear model.展开更多
目的:描述国内6所综合性儿童医院儿科重症监护室(Pediatric Intensive Care Unit,PICU)在中心静脉导管维护证据应用过程中评估及识别障碍因素的现状。方法:以“PICU中心静脉维护证据应用的多中心研究项目”的6个证据应用场所(PICU)障碍...目的:描述国内6所综合性儿童医院儿科重症监护室(Pediatric Intensive Care Unit,PICU)在中心静脉导管维护证据应用过程中评估及识别障碍因素的现状。方法:以“PICU中心静脉维护证据应用的多中心研究项目”的6个证据应用场所(PICU)障碍因素分析报告为研究对象,采用i-PARIHS理论框架中“变革”层面7个条目、“变革接受者”层面17个条目以及“组织环境”9个条目的3个评估清单,以单个证据应用场所评估内容完成率、单个条目评估完成率进行评价。结果:6个PICU对“变革”层面评估内容完成率、单个条目评估完成率均为100%,“变革接受者”层面的评估内容完成率为41.2%~82.4%,“组织环境”为11.1%~66.7%。所有的证据应用场所在“变革接受者”层面有3个条目、“组织环境”层面有2个条目均未作评估。结论:PICU中心静脉导管维护证据应用的障碍因素评估缺乏全面性和系统性,应采取有效的策略克服障碍因素以促进证据在临床的成功应用。展开更多
An accelerated decay test and a natural decay test were conducted synchronically to explore the strength degradation of decaying wood members under long-term exposure to natural environment.A natural decay test was ca...An accelerated decay test and a natural decay test were conducted synchronically to explore the strength degradation of decaying wood members under long-term exposure to natural environment.A natural decay test was carried out to measure the bending strength,compressive strength parallel to grain and modulus of elasticity of the wood members,with 6 groups of specimens decayed in natural environment for 3 to 18 months respectively.To compare with corresponding decay test,in which 6 other groups of specimens were measured under accelerated conditions.The experimental data collected were evaluated by Pearson productmoment for the correlation.The results indicate that the mechanical properties of the accelerated decay were highly correlated with those in natural environment,both of which decreased in the same trend.Under the given test conditions,the mean value of the accelerated decay test data were curve-fitted to achieve the time-dependent degradation model of the bending strength,the compressive strength parallel to grain,as well as the modulus of elasticity.Due to the high correlation,the acceleration shift factors(ASF)of the two tests were derived,where the bending strength of 2.934,the compressive strength parallel to grain of 2.519 and the elastic modulus of 2.346 were employed to formulate the strength degradation models in the long-term natural environment.The results verify that the exponential functionσ=σ0e^(-βt)enables to exactly capture the degradation of the mechanical properties of wood members decayed in natural environment.展开更多
[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction an...[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction and conventional extraction method, were used to prepare E. adenophorum extracts, and the herblcidal activity of E. adenophorum extracts extracted by 3 methods was studied by seed germination method. [ Result] The extraction rate of Soxhlet extraction was the highest of （22.54 ± 0.48 ）%, and the herbicidal activities of E. adenophorum extracted by Soxhlet extraction was relatively stronger. [ Conclusion] Soxhlet extraction was the better extraction method for herbicidal active substances of E. adenophorum.展开更多
For mistakes taken in pesticide bioassays, teaching experimental design is improved in the paper, so as to let students explore and analyze in teaching experiments to get a deeper understanding of theoretical knowledg...For mistakes taken in pesticide bioassays, teaching experimental design is improved in the paper, so as to let students explore and analyze in teaching experiments to get a deeper understanding of theoretical knowledge, thereby effectively avoiding frequently-taken mistakes in pesticide bioassays.展开更多
[ Objective ] The paper was to study the rooting promotion activity of plant extracts, so as to lay the foundation for development of natural source of roo- fing reagent with high efficiency, safety and environment fr...[ Objective ] The paper was to study the rooting promotion activity of plant extracts, so as to lay the foundation for development of natural source of roo- fing reagent with high efficiency, safety and environment friendship. [Method] Using mung bean rooting method, the rooting promotion effects of 33 plant extracts on mung bean section were studied. [Result] When the concentration was 1 mg/mL, Eupatorium adenophorum （stem and leaf）, Cryptomeriafortunei （stem and leaf）, Pinus yunnanensis （stem）, Pinus yunnanensis （leaf）, Rhododendron simsii （leaf）, Pinus armandii （leaf）, Litchi chinensis （pericarp）, P/nus armandiifruit （fruit） and Alnus cremastogyne （leaf） showed strong promotion effect on rooting of mung bean sections, and the rooting promotion rate reached over 100% ; the roo- ting promotion effect ofE. adenophorum （stem and leaf） was the strongest, reaching（1068.42 ＋7.87）%, which was extremely higher than the extracts of other plants. [Conclusion] E. adenophorum （stem and leaf）, C. fortunei （stem and leaf）, P. yunnanens/s （stem）, P. yurmanens/s （leaf）, R. simsii （leaf）, P. armandii （leaf）, L. chinensis （pericarp）, P. armandiifruit （fruit） and A. cremastogyne （leaf） all contained substances with st/ong rooting promotion effect, which could be further used for development of natural rooting reagent.展开更多
文摘A two-layer implicit difference scheme is employed in the present study to determine the temperature distribution in an asphalt pavement.The calculation of each layer only needs four iterations to achieve convergence.Furthermore,in order to improve the calculation accuracy a swarm intelligence optimization algorithm is also exploited to inversely analyze the laws by which the thermal physical parameters of the asphalt pavement materials change with temperature.Using the basic cuckoo and the gray wolf algorithms,an adaptive hybrid optimization algorithm is obtained and used to determine the relationship between the thermal diffusivity of two types of asphalt pavement materials and the temperature.As shown by the results,the prediction accuracy achievable with this approach is higher than that of the linear model.
文摘目的:描述国内6所综合性儿童医院儿科重症监护室(Pediatric Intensive Care Unit,PICU)在中心静脉导管维护证据应用过程中评估及识别障碍因素的现状。方法:以“PICU中心静脉维护证据应用的多中心研究项目”的6个证据应用场所(PICU)障碍因素分析报告为研究对象,采用i-PARIHS理论框架中“变革”层面7个条目、“变革接受者”层面17个条目以及“组织环境”9个条目的3个评估清单,以单个证据应用场所评估内容完成率、单个条目评估完成率进行评价。结果:6个PICU对“变革”层面评估内容完成率、单个条目评估完成率均为100%,“变革接受者”层面的评估内容完成率为41.2%~82.4%,“组织环境”为11.1%~66.7%。所有的证据应用场所在“变革接受者”层面有3个条目、“组织环境”层面有2个条目均未作评估。结论:PICU中心静脉导管维护证据应用的障碍因素评估缺乏全面性和系统性,应采取有效的策略克服障碍因素以促进证据在临床的成功应用。
基金supported by a grant from the National Natural Science Foundation of China(No.51208399)Natural Science Foundation of Hubei province of China(No.2018CFB645)Hubei Key Laboratory of Roadway Bridge and Structure Engineering(Wuhan University of Technology)(No.DQJJ201706).
文摘An accelerated decay test and a natural decay test were conducted synchronically to explore the strength degradation of decaying wood members under long-term exposure to natural environment.A natural decay test was carried out to measure the bending strength,compressive strength parallel to grain and modulus of elasticity of the wood members,with 6 groups of specimens decayed in natural environment for 3 to 18 months respectively.To compare with corresponding decay test,in which 6 other groups of specimens were measured under accelerated conditions.The experimental data collected were evaluated by Pearson productmoment for the correlation.The results indicate that the mechanical properties of the accelerated decay were highly correlated with those in natural environment,both of which decreased in the same trend.Under the given test conditions,the mean value of the accelerated decay test data were curve-fitted to achieve the time-dependent degradation model of the bending strength,the compressive strength parallel to grain,as well as the modulus of elasticity.Due to the high correlation,the acceleration shift factors(ASF)of the two tests were derived,where the bending strength of 2.934,the compressive strength parallel to grain of 2.519 and the elastic modulus of 2.346 were employed to formulate the strength degradation models in the long-term natural environment.The results verify that the exponential functionσ=σ0e^(-βt)enables to exactly capture the degradation of the mechanical properties of wood members decayed in natural environment.
基金Supported by Youth Fund Project of Yunnan Agricultural University
文摘[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction and conventional extraction method, were used to prepare E. adenophorum extracts, and the herblcidal activity of E. adenophorum extracts extracted by 3 methods was studied by seed germination method. [ Result] The extraction rate of Soxhlet extraction was the highest of （22.54 ± 0.48 ）%, and the herbicidal activities of E. adenophorum extracted by Soxhlet extraction was relatively stronger. [ Conclusion] Soxhlet extraction was the better extraction method for herbicidal active substances of E. adenophorum.
基金Supported by Construction Project of " National Teaching Team of Plant Protection" in 2008Construction Project of National " Plant Protection Specialty"( TS11138)Provincial Excellent Course Construction Project of Pesticide Science in Yunnan Province
文摘For mistakes taken in pesticide bioassays, teaching experimental design is improved in the paper, so as to let students explore and analyze in teaching experiments to get a deeper understanding of theoretical knowledge, thereby effectively avoiding frequently-taken mistakes in pesticide bioassays.
基金Supported by The Natural Science Foundation Project of Yunnan Province ( No. 2010CD056)
文摘[ Objective ] The paper was to study the rooting promotion activity of plant extracts, so as to lay the foundation for development of natural source of roo- fing reagent with high efficiency, safety and environment friendship. [Method] Using mung bean rooting method, the rooting promotion effects of 33 plant extracts on mung bean section were studied. [Result] When the concentration was 1 mg/mL, Eupatorium adenophorum （stem and leaf）, Cryptomeriafortunei （stem and leaf）, Pinus yunnanensis （stem）, Pinus yunnanensis （leaf）, Rhododendron simsii （leaf）, Pinus armandii （leaf）, Litchi chinensis （pericarp）, P/nus armandiifruit （fruit） and Alnus cremastogyne （leaf） showed strong promotion effect on rooting of mung bean sections, and the rooting promotion rate reached over 100% ; the roo- ting promotion effect ofE. adenophorum （stem and leaf） was the strongest, reaching（1068.42 ＋7.87）%, which was extremely higher than the extracts of other plants. [Conclusion] E. adenophorum （stem and leaf）, C. fortunei （stem and leaf）, P. yunnanens/s （stem）, P. yurmanens/s （leaf）, R. simsii （leaf）, P. armandii （leaf）, L. chinensis （pericarp）, P. armandiifruit （fruit） and A. cremastogyne （leaf） all contained substances with st/ong rooting promotion effect, which could be further used for development of natural rooting reagent.
