Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captur...Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captured by closely and circularly headspace way in adsorbent tubes and ATD-GC/MS on 29 April in Wanbailin Ecological Garden, China. VOCs from high altitude tree are more than low altitude in sunny site, and floral volatile constituents from upslope branches are less than downslope of the same tree on high altitude. Special floral VOCs were alpha-dimethyl-benzenemethanol, isopropyl palmitate, ethylbenzene, p-xylene, acetophenone, 3-ethyl-2-methyl-Heptane on sunny slope, and propylene glycol, decanal, hexadecane on shady slope. Dominant VOCs founded during 8 temporal quanta were toluene, hexane, 2-ethyl-1-hexanol, dodecane, pentadecane. Floral VOCs’ number from sunny slope was significantly negative correlated with flower-visiting insect community richness, abundance, diversity on sunny or shady slope, which from shady slope was significantly positive correlated with flower-visiting insect community parameters on both slopes tried dividing insects visiting floral branches from Prunus persica in sunny site with n/2 + 1 or n/2 - 1, and shady site with n/2 before sampled volatiles day. On sampled volatiles day, 2-ethyl-1-hexanol from sunny slope was significantly positive correlated with flower-visiting insect community parameters on shady slope (P Prunus persica on sunny slope, and even floral branches kept on shady slope.展开更多
Traditional outage model for the power equipment usually focus on the behavior of the equipment under random factors,and the availability of the power equipment in system analysis is usually confined to the steady val...Traditional outage model for the power equipment usually focus on the behavior of the equipment under random factors,and the availability of the power equipment in system analysis is usually confined to the steady value.However,this model may be inaccurate in the short term analysis,where the transient process of availability has not ended yet.Furthermore,the power equipment in the short term analysis might be influenced by both random factors and deterministic factors,yet the impact of deterministic factors cannot be completely reflected in the traditional outage model.Based on the above issues,a Markov-based transient outage model is proposed in this paper,which describes the deterioration and repair process of an equipment.Both the corrective maintenance and preventive maintenance are concerned in the model.The preventive maintenance in the model is considered as deterministic event,in which the start time and duration are both scheduled.Meanwhile the corrective maintenance and the unexpected failure are modeled as random events.The transient state probability and availability of equipment under preventive maintenance is derived.The effect of deterministic events on the availability of equipment is analyzed on numerical tests.The proposed model can be used in the short-term reliability assessment and maintenance scheduling in actual systems.展开更多
文摘Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captured by closely and circularly headspace way in adsorbent tubes and ATD-GC/MS on 29 April in Wanbailin Ecological Garden, China. VOCs from high altitude tree are more than low altitude in sunny site, and floral volatile constituents from upslope branches are less than downslope of the same tree on high altitude. Special floral VOCs were alpha-dimethyl-benzenemethanol, isopropyl palmitate, ethylbenzene, p-xylene, acetophenone, 3-ethyl-2-methyl-Heptane on sunny slope, and propylene glycol, decanal, hexadecane on shady slope. Dominant VOCs founded during 8 temporal quanta were toluene, hexane, 2-ethyl-1-hexanol, dodecane, pentadecane. Floral VOCs’ number from sunny slope was significantly negative correlated with flower-visiting insect community richness, abundance, diversity on sunny or shady slope, which from shady slope was significantly positive correlated with flower-visiting insect community parameters on both slopes tried dividing insects visiting floral branches from Prunus persica in sunny site with n/2 + 1 or n/2 - 1, and shady site with n/2 before sampled volatiles day. On sampled volatiles day, 2-ethyl-1-hexanol from sunny slope was significantly positive correlated with flower-visiting insect community parameters on shady slope (P Prunus persica on sunny slope, and even floral branches kept on shady slope.
基金supported by the Key Technologies Research and Development Program of China(No.2013BAA01B03)the National Natural Science Foundation of China(No.51177080,No.51321005)the Program for New Century Excellence Talents in University(No.NCET-11-0281)
文摘Traditional outage model for the power equipment usually focus on the behavior of the equipment under random factors,and the availability of the power equipment in system analysis is usually confined to the steady value.However,this model may be inaccurate in the short term analysis,where the transient process of availability has not ended yet.Furthermore,the power equipment in the short term analysis might be influenced by both random factors and deterministic factors,yet the impact of deterministic factors cannot be completely reflected in the traditional outage model.Based on the above issues,a Markov-based transient outage model is proposed in this paper,which describes the deterioration and repair process of an equipment.Both the corrective maintenance and preventive maintenance are concerned in the model.The preventive maintenance in the model is considered as deterministic event,in which the start time and duration are both scheduled.Meanwhile the corrective maintenance and the unexpected failure are modeled as random events.The transient state probability and availability of equipment under preventive maintenance is derived.The effect of deterministic events on the availability of equipment is analyzed on numerical tests.The proposed model can be used in the short-term reliability assessment and maintenance scheduling in actual systems.
