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The clutch size,incubation behavior of Reeves’s Pheasant(Syrmaticus reevesii) and their responses to ambient temperature and precipitation
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作者 Ting Jin Shuai Lu +7 位作者 Yunqi Wang Junqin Hua Zhengxiao Liu Qian Hu Yating Liu Yuze Zhao Jianqiang Li Jiliang Xu 《Avian Research》 SCIE CSCD 2024年第1期72-80,共9页
Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conserv... Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conservation.Reeves’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only incubation.However,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this species.Using satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,China.We explored their clutch size and incubation behavior,as well as their responses to ambient temperature and precipitation.Clutch size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding attempts.Throughout the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:00.Furthermore,females rarely left nests when daily precipitation was high.Recess duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of incubation.Additionally,there was a positive correlation between clutch size and recess duration.These results contribute valuable insights into the lifehistory features of this endangered species. 展开更多
关键词 ambient temperature Clutch size Incubation behavior PRECIPITATION Reeves’s Pheasant
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Awake rabbit model of ischemic spinal cord injury with delayed paraplegia:The role of ambient temperature
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作者 Wang Yang Qian-qian Wu +8 位作者 Lu Yang Yu-jie Chen Ren-qing Jiang Ling Zou Qing-shan Liu Guang-you Shi Jiang Cao Xiao-chao Yang Jian Sun 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第5期732-739,共8页
Background:Paraplegia after spinal cord ischemia is a devastating condition in the clinic.Here,we develop an awake rabbit model of spinal cord ischemia with delayed paraplegia and explore the influence of ambient temp... Background:Paraplegia after spinal cord ischemia is a devastating condition in the clinic.Here,we develop an awake rabbit model of spinal cord ischemia with delayed paraplegia and explore the influence of ambient temperature on the outcomes after injury.Methods:A total of 47 male rabbits were involved in the present study.Transient spinal cord ischemia was induced by occluding the infrarenal abdominal aorta of awake rabbits at different ambient temperatures.To find the optimal conditions for developing delayed paraplegia,hindlimb motor function after ischemia was evaluated between experiments.Results:The onset and magnitude of ischemic injury varied with the ambient temperature maintained during the peri-i schemia period.More serious spinal cord injury occurred when ischemia was induced at higher temperatures.At 18°C,25-minute ischemia resulted in 74%of rabbits developing delayed paraplegia.At a temperature of 28°C or higher,most of the animals developed acute paraplegia immediately.While at 13°C,rabbits usually regained normal motor function without paraplegia.Conclusion:This awake rabbit model is highly reproducible and will be helpful in future studies of delayed paraplegia after spinal cord ischemia.The ambient temperature must be considered while using this model during investigation of therapeutic interventions. 展开更多
关键词 ambient temperature delayed paraplegia rabbit model spinal cord injury spinal cord ischemia
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Association between Low Ambient Temperature and the Severity of Acute Ischemic Stroke
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作者 Xinyi Huang Liming Shu +5 位作者 Su Xiao Qiuhong Jiang Shiliang Yang Hualiang Liang Hua Hong Liang Luo 《Journal of Clinical and Nursing Research》 2024年第5期83-94,共12页
Objective:To explore the relationships among ambient temperature,ischemic stroke severity,and blood pressure.Methods:Meteorological data(2005–2015)were collected from the Guangzhou Meteorological Data Service.Ischemi... Objective:To explore the relationships among ambient temperature,ischemic stroke severity,and blood pressure.Methods:Meteorological data(2005–2015)were collected from the Guangzhou Meteorological Data Service.Ischemic stroke patients from the Department of Neurology of the First Affiliated Hospital,Sun Yat-sen University were retrospectively evaluated,each winter from 2005 to 2015.Patient demographics,baseline measurements,and National Institute of Health Stroke Scale(NIHSS)score were evaluated.Results:Three hundred sixty-two patients were included.The median latency from symptom onset to admission was 2 d(IQR:1–3 d).During recruitment,the highest and lowest temperatures were 39℃and 1.3℃,respectively.Hypertension was the most common comorbidity(75.1%).NIHSS scores at admission and discharge were higher in the cold-exposed group than in the controls regardless of the average temperature at admission.In addition,systolic and diastolic blood pressure values at admission were higher in the cold-exposed group than in the controls.When stratified by hypertensive status,the average and minimum temperatures at admission were negatively associated with systolic and diastolic blood pressure values in hypertensive patients.Reductions in the average and minimum temperatures at symptom onset were associated with more severe stroke.Conclusion:Ischemic stroke patients with symptom onset in winter had higher systolic blood pressure values and more serious neurologic deficits upon admission. 展开更多
关键词 Low ambient temperature STROKE Blood pressure SEVERITY
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Ambiently fostering solid electrolyte interphase for low-temperature lithium metal batteries 被引量:3
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作者 Jia-Yue Duan Jin-Xiu Chen +7 位作者 Fang-Fang Wang Jin-Hao Zhang Xiao-Zhong Fan Liping Wang Yingze Song Wei Xia Yusheng Zhao Long Kong 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期473-478,I0012,共7页
Despite being a leading candidate to meet stringent energy targets,lithium(Li) metal batteries(LMBs)face severe challenges at low temperatures such as dramatic increase in impedance,capacity loss and dendrite growth.U... Despite being a leading candidate to meet stringent energy targets,lithium(Li) metal batteries(LMBs)face severe challenges at low temperatures such as dramatic increase in impedance,capacity loss and dendrite growth.Unambiguously fingerprinting rate-limited factors of low-temperature LMBs would encourage targeted approaches to promote performances.Herein,the charge transfer impedance across solid electrolyte interphase(SEI) is identified to restrict battery operation under low temperature,and we propose a facile approach on the basis of ambiently fostering SEI(af-SEI) to facilitate charge transfer.The concept of af-SEI stems from kinetic benefits and structural merits to construct SEI at ambient temperature over low temperature developed SEI that is temporally consuming to achieve steady state and that is structurally defective to incur dendrite growth.The af-SEI allows ionically conductive and morphologically uniform layer on the anode surface,which exhibits a lower resistance and induces an even deposition of Li in the subsequent low temperature battery operation.Armed with af-SEI,the LMBs deliver the improved rate performance and prolonged cycle life when subjected to low temperature cycling.This work unveils the underlying causes that limit low temperature LMB performances,and enlightens the facile test protocols to build up favorable SEI,beyond scope of material and morphology design. 展开更多
关键词 Li matel batteries ambiently fostering SEI Charge transfer impedance Low temperature kinetics
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The impact of low ambient temperature on cardiovascular health
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作者 Guoqing Zhang Cuiqing Liu Qinghua Sun 《Frigid Zone Medicine》 2023年第3期167-175,共9页
Extreme weather events and climate change have witnessed a substantial increase in recent years,leading to heightened concerns.The rise in abnormal ambient temperatures,both in intensity and frequency,directly and ind... Extreme weather events and climate change have witnessed a substantial increase in recent years,leading to heightened concerns.The rise in abnormal ambient temperatures,both in intensity and frequency,directly and indirectly impacts cardiovascular health.While the impact of high ambient temperatures on cardiovascular response is a common concern in the context of global warming,the significance of low temperatures cannot be overlooked.The challenges posed by low temperatures contribute to increased cardiovascular morbidity and mortality,posing a significant threat to global public health.This review aims to provide an overview of the relationship between low ambient temperature and cardiovascular health,encompassing the burden of cardiovascular outcomes and underlying mechanisms.Additionally,the review explores strategies for cold adaptation and cardioprotection.We posit that to optimize cold adaptation strategies,future research should delve deeper into the underlying mechanisms of cardiovascular health in response to low ambient temperature exposure. 展开更多
关键词 low ambient temperature cardiovascular health cold adaptation
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Low ambient temperature and air pollution are associated with hospitalization incidence of coronary artery disease:Insights from a cross-sectional study in Northeast China
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作者 Rui Jiang Lingling Xu +4 位作者 Yue Liu Guangna Zhao Chun Xing Youyuan Li Yongchen Wang 《Frigid Zone Medicine》 2023年第4期232-241,I0007-I0013,共17页
Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for asso... Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes,especially in cold regions.This study aimed to systematically investigate the relationship between exposure to meteorological changes,air pollutants,and hospitalization for CAD in cold regions.Methods:We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1,2009,and December 31,2019.Poisson regression analysis,based on generalized additive models,was applied to estimating the influence of hospitalization for CAD.Results:Significant associations were found between low ambient temperature[-10℃,RR=1.65;95%CI:(1.28-2.13)]and the incidence of hospitalization for CAD within a lag of 0-14 days.Furthermore,O_(3)[95.50μg/m^(3),RR=12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.Furthermore,O_(3)[95.50μg/m^(3),RR=1.12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO_(2)and O_(3)concentrations were higher,with a pronounced effect at 7 days,dissipating by lag 14 days.No significant associations were observed between exposure to PM,SO_(2),air pressure,humidity,or wind speed and hospitalization incidences due to CAD and its subtypes.Conclusion:Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants(O_(3)and NO_(2))and hospitalizations for CAD,STEMI,and NSTEMI.These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events. 展开更多
关键词 meteorological changes ambient temperature air pollution coronary heart disease Poisson regression analysis
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Influence of Ambient Temperature on the Thermal Safety of Fireworks Products in Civil Aviation Transportation
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作者 Lingling Ji 《Proceedings of Business and Economic Studies》 2023年第2期45-54,共10页
Fireworks products are energy-containing materials and are hazardous during production,storage,transportation,and use.By analyzing the range of civil aviation ground ambient temperature and civil aviation cabin ambien... Fireworks products are energy-containing materials and are hazardous during production,storage,transportation,and use.By analyzing the range of civil aviation ground ambient temperature and civil aviation cabin ambient temperature in storage and ground operation as well as establishing a spontaneous combustion mathematical model for cylindrical fireworks products based on the spontaneous combustion theory,we identified the critical temperature for spontaneous combustion of a single spray and analyzed the thermal safety of fireworks products under the civil aviation ambient temperature by example to provide theoretical support for the feasibility study of transporting fireworks products by civil aviation. 展开更多
关键词 Civil aviation ambient temperature FIREWORKS Spontaneous combustion theory Thermal safety
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Study on Desulfurization Efficiency and Products of Ce-Doped Nanosized ZnO Desulfurizer at Ambient Temperature 被引量:13
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作者 李芬 闫波 +4 位作者 张杰 姜安玺 邵纯红 孔祥吉 王新 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第3期306-310,共5页
Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfur... Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly,compared to nanosized ZnO desulfurizer.Nanosized Ce-ZnO desulfurizer was characterized by XRD,TPD-MS,XPS,and TEM.The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product.There were adsorption complexes of HS and S on the surface of desulfurizer as well.Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization. 展开更多
关键词 nanosized ZnO Ce-doped desulfurization at ambient temperature rare earths
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Degradation of phenol in an upflow anaerobic sludge blanket(UASB) reactor at ambient temperature 被引量:3
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作者 KEShui-zhou SHIZhou +1 位作者 ZHANGTong HerbertH.P.FANG 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期525-528,共4页
A synthetic wastewater containing phenol as sole substrate was treated in a 2 8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were disc... A synthetic wastewater containing phenol as sole substrate was treated in a 2 8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were discussed, microbial population in the UASB sludge was identified based on DNA cloning, and pathway of anaerobic phenol degradation was proposed. Phenol in wastewater was degraded in an UASB reactor at loading rate up to 18 gCOD/(L·d), with a 1:1 recycle ratio, at 26±1℃, pH 7 0—7 5. An UASB reactor was able to remove 99% of phenol up to 1226 mg/L in wastewater with 24 h of hydraulic retention time(HRT). For HRT below 24 h, phenol degradation efficiency decreased with HRT, from 95 4% at 16 h to 93 8% at 12 h. It further deteriorated to 88 5% when HRT reached 8 h. When the concentration of influent phenol of the reactor was 1260 mg/L(corresponding COD 3000 mg/L), with the HRT decreasing(from 40 h to 4 h, corresponding COD loading increasing), the biomass yields tended to increase from 0 265 to 3 08 g/(L·d). While at 12 h of HRT, the biomass yield was lower. When HRT was 12 h, the methane yield was 0 308 L/(gCOD removed), which was the highest. Throughout the study, phenol was the sole organic substrate. The effluent contained only residual phenol without any detectable intermediates, such as benzoate, 4 hydrobenzoate or volatile fatty acids(VFAs). Based on DNA cloning analysis, the sludge was composed of five groups of microorganisms. Desulfotomaculum and Clostridium were likely responsible for the conversion of phenol to benzoate, which was further degraded by Syntrophus to acetate and H 2/CO 2. Methanogens lastly converted acetate and H 2/CO 2 to methane. The role of epsilon Proteobacteria was, however, unsure. 展开更多
关键词 ambient temperature anaerobic degradation PHENOL UASB DNA WASTEWATER
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Partial Nitrification from Domestic Wastewater by Aeration Control at Ambient Temperature 被引量:11
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作者 彭永臻 高守有 +1 位作者 王淑莹 白璐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期115-121,共7页
The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational param... The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater. There was a prolgrammed decrease of the airflow rate to 28L·h^-1, the corresponding average dissolved oxygen (DO) was 0.32mg·h^-1, and the average nitrite accumulation rate increased to 92.4% in 3 weeks. Subsequently, further increase in the airflow rate to 48L·h^-1 did not destroy the partial nitrification to nitrite, with average DO of 0.60mg·h^-1 and nitrite accumulating rate of 95.6%. The results showed that limited airflow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction. 展开更多
关键词 partial nitrification oxygen-limiting condition ambient temperature domestic wastewater
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Theoretical analysis of the surface temperature regulation of an infrared false target subjected to periodical ambient conditions 被引量:2
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作者 Shi-min LI Hong YE Qi-zhao LIN 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第5期360-366,共7页
Infrared false target is an important mean to induce the infrared-guided weapons,and the key issue is how to keep the surface temperature of the infrared false target to be the same as that of the object to be protect... Infrared false target is an important mean to induce the infrared-guided weapons,and the key issue is how to keep the surface temperature of the infrared false target to be the same as that of the object to be protected.One-dimensional heat transfer models of a metal plate and imitative material were established to explore the influences of the thermophysical properties of imitative material on the surface temperature difference(STD) between the metal plate and imitative material which were subjected to periodical ambient conditions.It is elucidated that the STD is determined by the imitative material’s dimensionless thickness(dim*,) and the thermal inertia(Pim).When dim* is above 1.0,the STD is invariable as long as Pim is a constant.And if the dimensionless thickness of metal plate(d,m*) is also larger than 1.0,the STD approaches to zero as long as Pimis the same as the thermal inertia of metal plate(Pm).When dim* is between 0.08 and 1,the STD varies irregularly with Pim and dim*.However,if dm* is also in the range of 0.08-1,the STD approaches to zero on condition that Pim=Pm and dim*= dm*.If dim*,is below 0.08,the STD is unchanged when Pimdim* is a constant.And if dm* is also less than 0.08,the STD approaches to zero as long as Pimdim* = Pmdm*.Furthermore,an applicationoriented discussion indicates that the imitative material can be both light and thin via the application of the phase change material with a preset STD because of its high specific heat capacity during the phase transition process. 展开更多
关键词 Infrared false target Surface temperature Periodical ambient conditions Thermal inertia Dimensionless thickness
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Ambient Temperature and Outpatient Visits for Acute Exacerbation of Chronic Bronchitis in Shanghai: A Time Series Analysis 被引量:8
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作者 HUANG Fang ZHAO Ang +2 位作者 CHEN Ren Jie KAN Hai Dong KUANG Xing Ya 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第1期76-79,共4页
The association between ambient temperature and acute exacerbation of chronic bronchitis (AECB) was still unknown. Therefore, we performed an epidemiological study in a large hospital of Shanghai to explore the rela... The association between ambient temperature and acute exacerbation of chronic bronchitis (AECB) was still unknown. Therefore, we performed an epidemiological study in a large hospital of Shanghai to explore the relationship about temperature and outpatient visit for AECB. We adopted a quasi-Poisson generalized additive models and distributed lag nonlinear models to estimate the accumulative effects of temperature on AECB across multiple days. We found significant non-linear effects of cold temperature on hospital visits for AECB, and the potential effect of cold temperature might last more than 2 weeks. The relative risks of extreme cold (first percentiles of temperature throughout the study period) and cold (10th percentile of temperature) temperature over lags 0-14 d were 2.98 [95% confidence intervals (CI): 1.77, 5.04] and 1.63 (95% Ch 1.21, 2.19), compared with the 25th percentile of temperature. However, we found no positive association between hospital visits and hot weather. This study showed that exposure to both extreme cold and cold temperatures were associated with increased outpatient visits for AECB in a large hospital of Shanghai. 展开更多
关键词 AECB ambient temperature and Outpatient Visits for Acute Exacerbation of Chronic Bronchitis in Shanghai
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Improving tree health assessment accuracy at low temperatures:considering the effect of trunk ice content on electrical resistance and stress wave tomography
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作者 Jiaxing Guo Peng Wang +1 位作者 Yuting Wang Huadong Xu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1503-1510,共8页
Accurate decay detection and health assessment of trees at low temperatures is an important issue for forest management and ecology in cold areas.Low temperature ice formation on tree health assessment is unknown.Beca... Accurate decay detection and health assessment of trees at low temperatures is an important issue for forest management and ecology in cold areas.Low temperature ice formation on tree health assessment is unknown.Because electric resistance tomography and stress wave tomography are two widely used methods for the detection of tree decay,this study investigated the effect of ice content on trunk electrical resistance and stress wave velocity to improve tree health assessment accuracy.Moisture content,trunk electrical resistance and stress wave velocity using time domain reflectometry were carried out on Larix gmelinii and Populus simonii.Ice content is based on moisture content data.The ice content of both species showed a trend of increasing and then decreasing.This was opposite with ambient temperatures.With the decrease of temperatures,daily average ice content increased,but the range narrowed gradually and both electrical resistance and stress wave velocity increased.Both increased rapidly near 0℃,mainly caused by ice formation(phase change and freezing of free water)in live trees.In addition,both are positively correlated with ice content.The results suggest that ice content should be considered for improving the accuracy of tree decay detection and health evaluation using electric resistance tomography and stress wave velocity methods under low temperatures. 展开更多
关键词 Cross-section electrical resistance Cross-section stress wave velocity ambient temperatures Ice content Wood decay detection Tree heath
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Cerium (IV) Ammonium Nitrate (CAN) Mediated Reactions IV. A Highly Efficient Synthesis of N,N’-Diarylsubstituted Formamidines in Water at Ambient Temperature 被引量:2
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作者 Kamal Usef Sadek Abdulaziz Alnajjar +2 位作者 Ramadan Ahmed Mekheimer Nasr Kamel Mohamed Haney A. Mohamed 《Green and Sustainable Chemistry》 2011年第3期92-97,共6页
A green, simple and highly efficient synthesis of N,N-diarylsubstituted formamidines has been developed employs reaction of triethylorthoformate (TEO) with aromatic amines catalyzed by cerium (IV) ammonium nitrate (CA... A green, simple and highly efficient synthesis of N,N-diarylsubstituted formamidines has been developed employs reaction of triethylorthoformate (TEO) with aromatic amines catalyzed by cerium (IV) ammonium nitrate (CAN) in water at ambient temperature. This method offers the advantages of proceeding under environmentally friendly technique with high yields and simplicity either in conducting the reaction or handling the products. 展开更多
关键词 CAN Triethylorthoformate AROMATIC AMINES WATER ambient temperature
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Effects of low ambient temperatures and dietary vitamin C supplementation on pulmonary vascular remodeling and hypoxic gene expression of 21-d-old broilers 被引量:1
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作者 ZENG Qiu-feng YANG Xia +7 位作者 ZHENG Ping ZHANG Ke-ying LUO Yu-heng DING Xue-mei BAI Shi-ping WANG Jian-ping XUAN Yue SU Zhuo-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期183-190,共8页
The objective of this study was to evaluate the effects of low ambient temperature (LAT) and dietary vitamin C (VC) sup- plementation on pulmonary vascular remodeling (PVR) and the relative expression of hypoxia... The objective of this study was to evaluate the effects of low ambient temperature (LAT) and dietary vitamin C (VC) sup- plementation on pulmonary vascular remodeling (PVR) and the relative expression of hypoxia inducible factor-la (HIF-la), vascular endothelial growth factor (VEGF) and its receptor 2 (VEGFR-2) mRNA of lungs in 21-d-old broilers. 400 1-d-old male Cobb broilers were assigned randomly to 4 treatments as follows for 21 d: 1 ) LAT and a basal diet; 2) LAT and a basal diet supplemented with 1 000 mg kg-1 VC (LAT+VC); 3) normal ambient temperature (NAT) and a basal diet; 4) NAT and a basal diet supplemented with 1 000 mg kg-1 VC (NAT+VC). Each treatment was composed of 10 replicates of 10 birds per replicate. Samples of lung were collected after the broilers were killed at d 21. LAT increased the ratio of vessel wall area to vessel total area (WA/TA, %) and mean media thickness in pulmonary arterioles (mMTPA, %) (P〈0.05). Dietary VC supplementation decreased mMTPA (P〈0.05), but had no effect on the WA/TA. LAT increased (P〈0.05) the relative mRNA expression of HIF-la, VEGF and VEGFR-2, while adding VC to the diet could decrease (P〈0.05) their relative mRNA expression. A significant positive correlation existed between the level of VEGF mRNA expression and the value of WA/WT (P〈0.05) or mMTPA (P〈0.05). These results suggested LAT resulted in pulmonary vascular remodeling, and the increase of HIF-la, VEGF and VEGFR-2 mRNA expression, and dietary VC supplementation can alleviate pulmonary vascular remodeling in broiler by affecting these gene expression. 展开更多
关键词 BROILER hypoxia inducible factor-la low ambient temperature pulmonary vascular remodeling vitamin C
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Influence of the ambient air temperature on the electrical contact reliability of electromagnetic relay 被引量:2
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作者 YAO Fang ZHENG Jian-rong HUANG Zhang-wu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期485-489,共5页
The dynamic contact resistances of HH52P electromagnetic relays are measured under different ambient air tem- perature. Their diagnostic parameters are extracted and determined. It is found that the ambient air temper... The dynamic contact resistances of HH52P electromagnetic relays are measured under different ambient air tem- perature. Their diagnostic parameters are extracted and determined. It is found that the ambient air temperature obviously influ- ences some parameters. In order to research its influence on the electrical contact reliability of electromagnetic relay, the statistic analysis is applied to study the static contact resistance, the max of the dynamic contact resistance and the bounce time. It is found that the ambient air temperature regularly influences the three parameters. Thoroughly, the phenomenon is studied and analyzed in the point of material science so as to probe into the essential matter of it. 展开更多
关键词 ambient air temperature Electromagnetic relay Electrical contact reliability Contact resistance Bounce time
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Novel-structured Mo-Cu-Fe-O composite for catalytic air oxidation of dye-containing wastewater under ambient temperature and pressure 被引量:3
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作者 Yin Xu Henan Shao +1 位作者 Fei Ge Yun Liu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第10期1719-1725,共7页
A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐progr... A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐programmed reduction by H2,cyclic voltammetry,and temperature‐programmed desorption by O2.The results showed that Mo6+diffused into the Cu‐Fe‐O crystal lattice and then formed a new crystalline phase of CuMoO4.The Mo‐Cu‐Fe‐O catalyst had redox properties,and its surface contained active sites for oxygen adsorption.In addition,the catalytic activity of the Mo‐Cu‐Fe‐O composite was evaluated by the degradation of Cationic Red GTL,Crystal Violet,and Acid Red in catalytic wet air oxidation(CWAO)at ambient temperature and pressure.The Mo‐Cu‐Fe‐O catalyst showed excellent activity at basic conditions for the degradation of Cationic Red GTL.High removal efficiencies of91.5%and92.8%were achieved for Cationic Red GTL and Crystal Violet,respectively,in wastewater,and the efficiency remained high after seven cycles.However,almost no degradation of Acid Red occurred in the CWAO process.Furthermore,hydroxyl radicals were formed in the CWAO process,which induced the decomposition of the two cationic dyes in wastewater,and the toxicity of their effluents was decreased after degradation.The results indicate that the Mo‐Cu‐Fe‐O composite shows excellent catalytic activity for the treatment of wastewater contaminated with cationic dyes. 展开更多
关键词 Mo‐Cu‐Fe‐O catalyst ambient temperature and pressure Dye wastewater Hydroxyl radical Oxidative degradation
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Effects of high ambient temperature on lipid metabolism in finishing pigs 被引量:2
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作者 WU Xin LI Ze-yang +4 位作者 JIA An-feng SU Hong-guang HU Chun-hong ZHANG Min-hong FENG Jing-hai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期391-396,共6页
In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ ... In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ with ad libitum access to feed(HT;n=8) and(2) ambient temperature of 22℃ and fed the average amount consumed by eight pigs in HT group on the previous day(PF;n=8).After 21 days of constant exposure to different environmental conditions,all the pigs were euthanized,and blood and tissue samples were obtained.High ambient temperature increased the proportion of backfat(P=0.04,+21.6%)and flare fat(P〈0.01,+43.3%).Compared with pair-fed pigs,the activities of fatty acid synthase(FAS) and malic enzyme in backfat and flare fat were lower(P〈0.05) in heat-stressed pigs,as were the amounts of acetyl-CoA-carboxylase and FAS in the longissimus muscle(LM),the amount of FAS in backfat(P〈0.01),and FAS activity in the liver(P〈0.01).Ambient temperature did not affect the amount of hormone-sensitive lipase in different tissues.The amount of lipoprotein lipase in flare fat tended to be higher(P=0.09,+28.3%),and the activities of β-hydroxyacyl coenzyme A dehydrogenase in front and back of LM were lower(P〈0.01,-48.3 and-49.8%,respectively) at 30℃ than at 22℃.The plasma concentration of high-density lipoprotein tended to be lower(P=0.08),but the plasma concentrations of very low-density lipoprotein(VLDL)(P=0.09,+50.0%) and nonestesterified fatty acid(NEFA)(P=0.04,+44.2%) were higher in heat-stressed pigs.We concluded that high ambient temperature depressed de novo fatty acid synthesis in both adipose tissues and the liver.However,β-oxidation of fatty acid in skeletal muscles was also inhibited in the high-temperature environment.As a result,more plasma NEFAs were used to synthesize VLDLs in the liver and were absorbed by adipose tissues.This may be one reason that high ambient temperature enhances the accumulation of backfat and flare fat in finishing pigs. 展开更多
关键词 β-hydroxyacyl coenzyme A dehydrogenase lipoprotein lipase lipogenesis finishing pigs high ambient temperature
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Ambient temperature cured TiB_2 cathode coating for aluminum electrolysis 被引量:4
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作者 赖延清 李庆余 +1 位作者 杨建红 李劼 《中国有色金属学会会刊:英文版》 CSCD 2003年第3期704-707,共4页
The concept of ambient temperature curable TiB 2 cathode coating was put forward, and the ambient temperature curable TiB 2 cathode coating was prepared successfully. Differing from the previous TiB 2 cathode coating ... The concept of ambient temperature curable TiB 2 cathode coating was put forward, and the ambient temperature curable TiB 2 cathode coating was prepared successfully. Differing from the previous TiB 2 cathode coating solidified approximately at 200 ℃,the ambient temperature curable TiB 2 cathode coating can be solidified at room temperature, so the heating equipment is not necessary, which simplifies the preparation process and facilitates the industrial application of TiB 2 cathode coating. Many kinds of resin and curing agent were investigated. On the above mentioned basis, the ambient temperature curable TiB 2 cathode coating was prepared with furan resin 5 500 mixed with complex resins B as carbon binder and DXG1 as curing agent in 24 h. The results show that the properties of prepared coating are excellent, the electrical resistivity is 29.8 μΩ·m, the compressive strength is 33.6 MPa, which are all better than the relevant properties of partially graphitized cathode carbon block for aluminum electrolysis prescribed by the GB 8744 88. SEM morphologies show that the section morphology of the TiB 2 coating is unaltered during the electrolysis test, the TiB 2 coating can be used in aluminum electrolysis industry to save energy and prolong the life of aluminum electrolysis cell. 展开更多
关键词 炼铝 电解 环境温度 二硼化钛 阴极涂层
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Evaluation of the Influence of Ambient Temperature on the Performance of the Trans-Amadi Gas Turbine Plant 被引量:1
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作者 Emughiphel Nelson Igoma Barinaada Thaddeus Lebele-Alawa John Sodiki 《Journal of Power and Energy Engineering》 2016年第11期19-31,共13页
This paper examines the effects of ambient temperature on the Trans-Amadi gas turbine power station Phase II. The investigation took thirteen (13) months (January 2012 to January 2013) during which plant data were mon... This paper examines the effects of ambient temperature on the Trans-Amadi gas turbine power station Phase II. The investigation took thirteen (13) months (January 2012 to January 2013) during which plant data were monitored and operational Logsheets like turbine logsheets, plant—auxiliaries’ logsheets and generator logsheets were studied. The gas turbine (GT) that was under investigation was GT-2: MS5001 Nuovopignone with designed installed capacity of 25.0 Megawatts (MW). The result of the study shows that a 1℃ rise of the ambient temperature is responsible for the following: 0% - 0.12% decrease in the power output, 0% - 0.12% increase in the power differential, 0% - 1.17% decrease in the thermal efficiency, 0% - 27.18% increase in the heat rate and 0% - 3.57% increase in the specific fuel consumption. An ambient temperature of 30℃ is found to yield minimal fuel consumption. 展开更多
关键词 ambient temperature PERFORMANCE Gas Turbine Power and Thermal Efficiency
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