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Abundance of general aerobic heterotrophic bacteria in the Bering Sea and Chukchi Sea and their adaptation to temperature 被引量:4
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作者 陈皓文 高爱国 +1 位作者 孙海青 矫玉田 《Chinese Journal of Polar Science》 2004年第1期39-46,共8页
The abundance of general aerobic heterotrophic bacteria(GAB) from the water and sediment in the Bering Sea and the Chukchi Sea was determined by using petri dish cultivation and counting method. The abundance of GAB a... The abundance of general aerobic heterotrophic bacteria(GAB) from the water and sediment in the Bering Sea and the Chukchi Sea was determined by using petri dish cultivation and counting method. The abundance of GAB among the different sea areas, sampling sites, layers of sediments surveyed and adaptability to differential temperatures was studied. The result obtained showed that: the occurrence percentage of GAB in the surface water was higher than that in sediment, but the abundance was only 0.17% of sediment. The occurrence percentage of GAB in surficial layer of sediment was higher than that in the other layers. The occurrence percentage of GAB in surficial layer of sediment was higher than that in the other layers. The occurrence percentage, abundance and its variation of GAB in the Bering Sea were higher than that in the Chukchi Sea respectively. The average value of the abundance in the all sediment surveyed was 3166.3×10 2 CFU·g -1(wet.). The abundance of GAB in sediment showed a trend: roughly higher in the lower latitudinal area than higher latitude. The results from temperature test mean that: the majority of bacteria tested were cold-adapted ones, minority might be mesophilic bacteria. The results indicated that, Arctic ocean bacteria had a stronger adaptability to environmental temperature. 展开更多
关键词 ARCTIC marine general aerobic heterotrophic bacteria ABUNDANCE adaptability to temperature.
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Thermally Dependent Behaviour of Cold-Blooded Animals: Overcoming Two Temperature Barriers on the Way to Warm-Blooded
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作者 Yulia S. Mednikova Sergei N. Kalabushev 《Journal of Behavioral and Brain Science》 CAS 2023年第5期95-112,共18页
Background: The temperature preferences of cold-blooded animals are different for different groups of animals and are closely related to their evolutionary status and level of adaptive capabilities. The range of prefe... Background: The temperature preferences of cold-blooded animals are different for different groups of animals and are closely related to their evolutionary status and level of adaptive capabilities. The range of preferred temperatures for reptiles (28°C - 32°C) coincides with the zone of temperature-dependent increase in the rate of the M-cholinergic reaction in the brain, which was previously found in warm-blooded neurons. The growth of the M-cholinergic process contributes to the transition of adaptive behavior to a higher level. Of the cold-blooded, only reptiles actively use thermoregulatory behavior as a tool to achieve a temperature optimum. This paper is devoted to the study of the behavior of red-eared turtles aimed at reaching the range of preferred temperatures. Temperature conditions necessary for the survival of different groups of cold-blooded animals are compared and the reason for temperature preferences is discussed. Methods: The behavior of turtles was studied under conditions of variable solar radiation and in a 3-section terrarium with gradual temperature ranges: 23°C - 24°C;28°C - 31°C and 45°C - 50°C. Results: It was found that prolonged (up to 1.5 hours) heating at a temperature of 45°C - 50°C was the best way to achieve the preferred temperatures. This method of heating results in increasing the temperature of the shell to an average of 37°C, followed by a very slow decrease during 4 - 6 hours within the limits that closely coincided with the preferred level. Conclusion: The results obtained demonstrate that the main function of the turtle shell is to accumulate heat and keep it for a long time in a variable climate. The preferred temperature achieved in this case is necessary for the temperature-dependent transition of the rate of the M-cholinergic reaction in the brain to a higher level, which creates more significant adaptive capabilities. The temperature range of the M-cholinergic process has two inflection points at 27°C - 29°C and 34°C - 36°C. In accordance with these values, the temperature preferences of cold-blooded animals are divided into three groups: 0°C - 28°C (fish and amphibians);28°C - 32°C (reptiles) and 34°C - 36°C (dinosaurs). Different ranges of preferred temperatures correspond to three stages of adaptive development. 展开更多
关键词 Preferred temperatures adaptive Capabilities TURTLES Shell Ice-Free Era Permian Period Mesozoic Era
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Ethylene purification in a metal–organic framework over a wide temperature range via pore confinement
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作者 Xue-Qian Wu Peng-Dan Zhang +4 位作者 Xin Zhang Jing-Hao Liu Tao He Jiamei Yu Jian-Rong Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1703-1710,共8页
The separation of C2H4from C_(2)H_(6)/C_(2)H_(4)mixture is of great importance but difficult and energy intensive. Adsorptive separation provides an alternative approach to ameliorate this situation. Here, we report a... The separation of C2H4from C_(2)H_(6)/C_(2)H_(4)mixture is of great importance but difficult and energy intensive. Adsorptive separation provides an alternative approach to ameliorate this situation. Here, we report a microporous metal–organic framework(MOF) BUT-315-a as a C_(2)H_(6)-selective adsorbent for the separation of C2H6/C2H4gas mixture. BUT-315-a combines good IAST selectivity of 2.35 with high C_(2)H_(6)uptake of 97.5 cm^(3)g^(-1), giving superior high separation potential ΔQ(2226 mmol L^(-1)) for equimolar C_(2)H_(6)/C_(2)H_(4) at 298 K. Impressively, such excellent performance can be preserved at higher temperatures of 313 and 323 K to accommodate industrial conditions. Efficient dynamic separation performance of BUT-315-a has been demonstrated by column breakthrough experiments under varied temperatures and gas ratios. Theoretical calculations further reveal multiple synergistic interactions between C_(2)H_(6) and the framework. This work highlights a new benchmark material for C_(2)H_(6)/C_(2)H_(4)separation and provides guidance for designing adsorbent for separation applications. 展开更多
关键词 Metal–organic framework Adsorptive separation Ethylene purification temperature adaptability Pore confinement
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Adaptive FEM Analysis of the Temperature Field of Pistons in Diesel Engines and Their Thermal Stress and Deformation Calculation 被引量:1
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作者 覃文洁 张儒华 左正兴 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期418-421,共4页
The adaptive FEM analysis of the temperature field of the piston in one diesel engine is given by using the ANSYS software. By making full use of the post results provided by the software, the posteriori error estimat... The adaptive FEM analysis of the temperature field of the piston in one diesel engine is given by using the ANSYS software. By making full use of the post results provided by the software, the posteriori error estimation and adaptive accuracy meshing algorithm is developed. So the blindness of the mesh design through experiences can be avoided, and the accuracy requirement is adapted to the relative temperature gradient distribution across the entire domain. Therefore the meshes and solutions can be obtained at the same time. Based on the temperature field analysis, the thermal stress and deformation fields are calculated as well. The results show that the stress concentrates on the edge of the piston pin boss and the inside surface of the first ring groove, and the deformation of the head of the piston is greatest. But the difference between the long and short axes of the bottom cross section is greatest. 展开更多
关键词 adaptive analysis temperature field thermal structural analysis PISTON
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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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SOFC temperature evaluation based on an adaptive fuzzy controller 被引量:1
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作者 Xiao-juan WU Xin-jian ZHU +1 位作者 Guang-yi CAO Heng-yong TU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期688-694,共7页
The operating temperature of a solid oxide fuel cell (SOFC) stack is a very important parameter to be controlled, which impacts the performance of the SOFC due to thermal cycling. In this paper, an adaptive fuzzy cont... The operating temperature of a solid oxide fuel cell (SOFC) stack is a very important parameter to be controlled, which impacts the performance of the SOFC due to thermal cycling. In this paper, an adaptive fuzzy control method based on an affine nonlinear temperature model is developed to control the temperature of the SOFC within a specified range. Fuzzy logic systems are used to approximate nonlinear functions in the SOFC system and an adaptive technique is employed to construct the controller. Compared with the traditional fuzzy and proportion-integral-derivative (PID) control, the simulation results show that the designed adaptive fuzzy control method performed much better. So it is feasible to build an adaptive fuzzy controller for temperature control of the SOFC. 展开更多
关键词 Solid oxide fuel cell (SOFC) temperature control adaptive fuzzy controller Affine temperature model
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Evidences on adaptive mechanisms for cardiorespiratory diseases regarding extreme temperatures and air pollution:A comparative systematic review
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作者 Helena Madureira Maria Pacheco +3 位作者 Carlos Sousa Ana Monteiro Francesca De’-Donato Manuela De-Sario 《Geography and Sustainability》 2021年第3期182-194,共13页
The negative cardiorespiratory health outcomes due to extreme temperatures and air pollution are widely stud-ied,but knowledge about the effectiveness of the implementation of adaptive mechanisms remains unclear.The o... The negative cardiorespiratory health outcomes due to extreme temperatures and air pollution are widely stud-ied,but knowledge about the effectiveness of the implementation of adaptive mechanisms remains unclear.The objective of this paper is to explore the evidence of adaptive mechanisms for cardiorespiratory diseases regard-ing extreme temperatures and air pollution by comparing the results of two systematic literature review(SLR)processes sharing the same initial research question but led by two research groups with different academic back-grounds working in the same multidisciplinary team.We start by presenting the methodological procedures and the results of the SLR triggered by the research group mainly composed by researchers with a background in ge-ography(named geographical strategy).We then compare these results with those achieved in the SLR led by the research group with a background in epidemiology(named epidemiological strategy).Both SLR were developed under the EU Horizon 2020 Project“EXHAUSTION”.The results showed:1)the lack of evidence regarding the effectiveness of adaptation measures,namely due to the limited number of studies about the topic,the prepon-derance of studies dedicated to heat extremes or the unbalance between different adaptation measures;2)that the choice of search terms in the geographical strategy,despite being more comprehensive at first sight,ended up retrieving less results,but it brought new studies that can complement the results of the epidemiological strategy.Therefore,it is suggested that to strengthen the empirical evidence of the effectiveness of adaptation measures,powerful multidisciplinary teams should work together in the preparation of SLR in topics of great complexity,such as the one presented in this paper. 展开更多
关键词 Cardiopulmonary diseases Extreme temperatures Air pollution adaptation Planning Systematic literature review(SLR)
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Adaptive output-feedback power-level control for modular high temperature gas-cooled reactors
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作者 董哲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期2092-2097,共6页
Small modular reactors(SMRs) are beneficial in providing electricity power safely and viable for specific applications such as seawater desalination and heat production. Due to its inherent safety feature, the modular... Small modular reactors(SMRs) are beneficial in providing electricity power safely and viable for specific applications such as seawater desalination and heat production. Due to its inherent safety feature, the modular high temperature gas-cooled reactor(MHTGR) is considered as one of the best candidates for SMR-based nuclear power plants. Since its dynamics presents high nonlinearity and parameter uncertainty, it is necessary to develop adaptive power-level control, which is beneficial to safe, stable, and efficient operation of MHTGR and is easy to be implemented. In this paper, based on the physically-based control design approach, an adaptive outputfeedback power-level control is proposed for MHTGRs. This control can guarantee globally bounded closedloop stability and has a simple form. Numerical simulation results show the correctness of the theoretical analysis and satisfactory regulation performance of this control. 展开更多
关键词 High temperature gas-cooled reactor Power-level regulation adaptive control
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Effects of High Temperature on Activities of Some Protective Enzymes in Mononychellus tanajoa
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作者 卢芙萍 经福林 +4 位作者 赖开枕 郑友枫 徐雪莲 卢辉 陈青 《Agricultural Science & Technology》 CAS 2012年第3期672-677,共6页
[Objective] Mononychellus tanajoa is a mite speices recently invaded into China in 2008. Temperature is one of the most important ecological factors affecting the growth and reproduction of M. tanajoa. The objective o... [Objective] Mononychellus tanajoa is a mite speices recently invaded into China in 2008. Temperature is one of the most important ecological factors affecting the growth and reproduction of M. tanajoa. The objective of the current study was to reveal the effects of high temperature incubation on the activities of some protective enzymes in M. tanajoa at different growth stages. The results would contribute to the understanding of the adaptable distribution of M. tanajoa after its invasion into China, the mechanisms in its invasion, diffusion and ecological adaptation, and the monitor- ing, early warning and effective prevention of its damage. [Method] Six protective enzymes, Le. polyphenol oxidase (PPO), peroxidase (POD), ascorbate oxidase (AsA- POD), catalase (CAT), superoxide dismutase (SOD) and esterase (EST), were cho- sen to study their activities after the mites at different growth stages were incubated at a extremely high temperature of 42 ~C for a certain period of time up to 24 h. The activities were measured by spectrophotometric endpoint assay method. [Results] Enzyme activities in M. tanajoa were affected by the high temperature incubation. However, differences in enzyme activity changes were found among different protec- tive enzymes and among different growth stages of M. tanajoa. Activities of PPO, POD, AsA-POD and CAT were significantly increased in the larval mites and female adult mites of M. tanajoa. CAT activity was significantly decreased in protonymph and deutonymph of M. tanajoa. Activities of PPO, POD and AsA-POD in protonymph and deutonymph showed no obvious difference from the control. [Conclusion] The activity changes of some protective enzymes in M. tanajoa following high-temperature treatment are part of its anti-stress reaction mechanism. In mite protonymph and deutonymph, activities of PPO, POD and AsA-POD are similar to the untreated con- trol which may be associated with the thermostability of M. tanajoa. It is concluded that, the long-time stress of extreme temperature may result in the increase of the thermostability of mite individuals, the enhancement of the population thermal stability and subsequently lead to rapid expansion of the population. 展开更多
关键词 Mononychellus tanajoa High temperature Protective enzyme Ther-mostability Ecological adaptability
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Assessing the energy saving potential of using adaptive setpoint temperatures:The case study of a regional adaptive comfort model for Brazil in both the present and the future
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作者 Daniel Sánchez-García David Bienvenido-Huertas +1 位作者 Carlos Rubio-Bellido Ricardo Forgiarini Rupp 《Building Simulation》 SCIE EI CSCD 2024年第3期459-482,共24页
It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy conservation.Recent studies using adaptive setpoint temperatures incorporate... It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy conservation.Recent studies using adaptive setpoint temperatures incorporate international models from ASHRAE Standard 55 and EN16798-1.This study,however,has instead considered a regional Brazilian adaptive comfort model.This study investigates the energy demand arising from the use of a local Brazilian comfort model in order to assess the energy implications from the use of the worldwide ASHRAE Standard 55 adaptive model and various fixed setpoint temperatures.All of Brazil’s climate zones,full air-conditioning,mixed-mode building operating modes,present-day climate change scenarios,and future scenarios—specifically Representative Concentration Pathways(RCP)2.6,4.5,and 8.5 for the years 2050 and 2100—have all been taken into account in building energy simulations.The use of adaptive setpoint temperatures based on the Brazilian local model considering mixed-mode has been found to significantly reduce energy consumption when compared to static setpoint temperatures(average energy-saving values ranging from 52%to 58%)and the ASHRAE 55 adaptive model(average values ranging from 15%to 21%).Considering climate change and the mixed-mode Brazilian model,the overall energy demand for the three groups of climatic zones(annual average outdoor temperatures≤21℃,>21 and≤25℃and>25℃)ranged between 2%decrease and 5%increase,4%and 27%increase,and 13%and 45%increase,respectively.It is concluded as a consequence that setting setpoint temperatures based on the Brazilian local adaptive comfort model is a very efficient energy-saving method. 展开更多
关键词 adaptive thermal comfort building energy simulation energy efficiency climate change adaptive setpoint temperatures local comfort mode
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Three dimensional numerical simulation of welding temperature fields in stainless steel 被引量:9
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作者 董志波 魏艳红 +1 位作者 刘仁培 董祖珏 《China Welding》 EI CAS 2004年第1期11-15,共5页
Three kinds of mathematical models representing welding heat sources are presented. Among them, Gaussian model and double ellipsoidal model are used to analyze the thermal distributions with finite element method. At ... Three kinds of mathematical models representing welding heat sources are presented. Among them, Gaussian model and double ellipsoidal model are used to analyze the thermal distributions with finite element method. At the same time, this paper analyzed the influences of the heat source models, the latent heat and the welding parameters on the temperature distributions. The comparisons between the simulated results and the experiments show double ellipsoidal model is good for three-dimensional numerical simulations. Furthermore, the adaptive mesh technique is applied in the three-dimensional model which greatly reduces the number of nodes and elements in the simulation. 展开更多
关键词 double ellipsoidal model adaptive mesh technique welding temperature field stainless steel
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Effects of Low Temperature on Physiological Responses of Two White Clover Cultivars 被引量:1
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作者 Li Xun Wang Peng +5 位作者 Xie Fu-chun Sun Hua-shan Liu Ke-meng Guan Tong Fu Zhen-xuan Chen Ya-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第2期13-19,共7页
In order to explore the effects of low temperature on the two different genotypes of white clover, electrical conductivity (EC), soluble sugar, malondialdehyde (MDA) and some other physiological indexes of plants ... In order to explore the effects of low temperature on the two different genotypes of white clover, electrical conductivity (EC), soluble sugar, malondialdehyde (MDA) and some other physiological indexes of plants were compared under laboratory conditions. Seedlings of Longping No.1 and Koala were undergone a series of degrading temperatures set in turn 25℃, 10℃, 5℃, 0℃, –5℃ and –10℃. The results showed that the activities of superoxide dismutase (SOD), electrical conductivity, soluble sugar, free proline and MDA increased obviously with the decrease of stress temperature, while the content of starch decreased, and the content of soluble protein increased first and then decreased during the process. Comprehensive assessments on physiological responses to low temperature stress indicated that the cultivar Longping No.1 had stronger cold resistance than that of cultivar Koala. 展开更多
关键词 low temperature stress soluble sugar malondialdehyde (MDA) physiological adaptability
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Auto-Test on Motor Temperature Rising in Electric Vehicles with Mutual MRAS 被引量:1
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作者 王志福 张承宁 《Journal of Beijing Institute of Technology》 EI CAS 2008年第4期395-399,共5页
A new method to calculate the motor temperature rising in electric vehicle (EV) is proposed based on the stator resistance identification. The measure theory of the motor temperature rising with the stator resistanc... A new method to calculate the motor temperature rising in electric vehicle (EV) is proposed based on the stator resistance identification. The measure theory of the motor temperature rising with the stator resistance is discussed at first. An enhanced magnetism motor dynamic math model is built which is the research object. Then the resistance identification system model is built on the mutual model reference adaptive,system (MRAS) theory. The simulation diagram of the mutual MRAS model is constructed and the resistance identification performance is studied in different motor states. Simulation results indicate that the stator resistance identification model with the mutual MRAS is effective. At the same time, the identification of motor temperature rising is possible with the identification of the stator resistance. 展开更多
关键词 electric vehicle (EV) motor's temperature rising model reference adaptive system (MARS) resistance identification
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Simulation on an optimal combustion control strategy for 3-D temperature distributions in tangentially pc-fired utility boiler furnaces
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作者 WANGXi-fen ZHOUHuai-chun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期305-308,共4页
The control of 3-D temperature distribution in a utility boiler furnace is essential for the safe, economic and clean operation of pc-fired furnace with multi-burner system. The development of the visualization of 3-... The control of 3-D temperature distribution in a utility boiler furnace is essential for the safe, economic and clean operation of pc-fired furnace with multi-burner system. The development of the visualization of 3-D temperature distributions in pc-fired furnaces makes it possible for a new combustion control strategy directly with the furnace temperature as its goal to improve the control quality for the combustion processes. Studied in this paper is such a new strategy that the whole furnace is divided into several parts in the vertical direction, and the average temperature and its bias from the center in every cross section can be extracted from the visualization results of the 3-D temperature distributions. In the simulation stage, a computational fluid dynamics(CFD) code served to calculate the 3-D temperature distributions in a furnace, then a linear model was set up to relate the features of the temperature distributions with the input of the combustion processes, such as the flow rates of fuel and air fed into the furnaces through all the burners. The adaptive genetic algorithm was adopted to find the optimal combination of the whole input parameters which ensure to form an optimal 3-D temperature field in the furnace desired for the operation of boiler. Simulation results showed that the strategy could soon find the factors making the temperature distribution apart from the optimal state and give correct adjusting suggestions. 展开更多
关键词 tangentially-fired boilers combustion control three-dimensional temperature distributions adaptive genetic algorithm
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The environmental adaptability and reproductive properties of invasive green alga Codium fragile from the Nan'ao Island,South China Sea
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作者 Lanping Ding Xulei Wang +2 位作者 Bingxin Huang Weizhou Chen Shanwen Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第3期70-75,共6页
It has been widely recognized that biological invasion has become one of the greatest threats to the ecosystem.Codium fragile is an invasive species which exhibits a variety of attributes like parthenogenesis,winter f... It has been widely recognized that biological invasion has become one of the greatest threats to the ecosystem.Codium fragile is an invasive species which exhibits a variety of attributes like parthenogenesis,winter fragment,and vegetative reproduction;and therefore,it has become a successful invader,colonizing most subtropical regions.In China’s southeast coastal aquaculture waters,the green algal bloom caused by C.fragile will probably become a serious problem.In order to understand more details about the species,an experiment focused on its reproductive characteristics was conducted using culture established from a sample collected in the aquaculture raft of the Nan’ao Island in the South China Sea.The results showed that there were two types of gametes resembling aplanospores and zoospores respectively,both of which were able to germinate.During the gametes liberation,a long mucilage tube was formed out of the mouth of the gametangium assisting dispersal of gametes away from the parent plant.This tube was adapted not only to its surrounding flowing water environment but also to its parent plant’s outer gelatinous structure.In general,the optimum temperature for gametes release and germination was 15-20℃ and 15℃,respectively,which corresponded to the local offshore marine water.The plant was observed to produce vegetative buds under favourable reproductive conditions which were called propagules.They were capable of developing into filamentous thalli.The results will provide some scientific evidences for revealing the biological mechanism of bloom and control strategies of invasive green algae. 展开更多
关键词 Codium fragile GAMETES PROPAGULES mucilage tube temperature environmental adaptation
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Study on changes of plasmalemma permeability and some primary inorganic ions of Antarctic ice microalgae (Chlamydomonas sp. ICE-L) in the low-temperature stress 被引量:1
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作者 郑洲 缪锦来 +2 位作者 陈豪 张波涛 李光友 《Chinese Journal of Polar Science》 2006年第1期20-29,共10页
The changes of plasmalemma permeability and some primary inorganic ions of Antarctic ice microalgae ( Chlamydomonas sp. ICE-L) in the low-temperature stress were examined. The plasmalemma of 1CE-L could maintain the... The changes of plasmalemma permeability and some primary inorganic ions of Antarctic ice microalgae ( Chlamydomonas sp. ICE-L) in the low-temperature stress were examined. The plasmalemma of 1CE-L could maintain the stability at the freezing condition of -6 ℃. That signifies that it could maintain the proper function of plasmalemma and stability of the intracellular environment during sea ice formation. The function of inorganic ions on low-temperature adaptation of ICE-L was investigated by using the X-ray microanalysis method. Low temperature (0 - -6 ℃ ) induces Ca^2 + concentration increment of cytoplasm, but after 24 h the content decrease quickly to normal value. As a matter of fact, Ca^2 + plays an important role as the second messenger in the low temperature adaptation of ICE-L. In addition, low temperature also influences on the other primary inorganic ions transfer and the cell maintains activity by keeping ratio balance among different ions. Above all, it is necessary for Antarctic ice microalgae to survive and breed by maintaining the stability of K^ + content and the balance of Na^ +/Cl^ -. 展开更多
关键词 Antarctic ice microalga X-ray microanalysis inorganic ions low-temperature adaptation.
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Exploring the Nexus between Climate Hazards and Conflict in Lamu County: Implications for Community Adaptation Action Plans
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作者 Misiani Zachary Simeon Mwadiga +5 位作者 Mohamed Abubakar Hindada Boneya Onyango Linet Amos Okello Mohamed Rashid Dirie Monica Orero 《Journal of Environmental Protection》 2023年第12期984-1005,共22页
This paper investigated the complex relationship between climate change and security in Lamu County, with focus on community perceptions, vulnerabilities, and adaptation strategies. The study utilized a participatory ... This paper investigated the complex relationship between climate change and security in Lamu County, with focus on community perceptions, vulnerabilities, and adaptation strategies. The study utilized a participatory approach involving Focus Group Discussions (FGDs) and Key Informant Interviews (KIIs) to gather insights from diverse community members. Results revealed a growing recognition of climate change as a significant factor amplifying security risks, including resource-based conflicts, food and water insecurity, pest and disease outbreaks, and rising sea levels. The analysis of historical climate data indicated shifts in rainfall patterns and rising temperatures, exacerbating these hazards. Furthermore, it underscores the need to mainstream climate change actions across various sectors for sustainable development and human security. Lamu County in Kenya faces a myriad of security challenges stemming from climate change, with the community perceiving droughts, pests, diseases, and conflicts as prominent hazards. These climatic impacts have led to crop failures, livestock losses, water scarcity, property damage, displacement, and instability. Local adaptation strategies have shown varying degrees of effectiveness, highlighting the need for community-specific and sustainable solutions. The study identified local adaptation strategies and emphasized the importance of early warning systems, informed decision-making, and mainstreaming climate change actions across sectors to enhance human security and sustainable development. However, it also acknowledges limitations in community participation and suggests future research avenues to ensure the inclusion of marginalized voices in such studies. 展开更多
关键词 Kenya Climate Changes and adaptation Pollution Climate Hazards CONFLICT Security temperature Rainfall Sea Level Lamu County
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基于子循环自适应串行交错时间匹配算法的油浸式变压器绕组瞬态温升计算 被引量:3
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作者 刘刚 郝世缘 +2 位作者 胡万君 刘云鹏 李琳 《电工技术学报》 EI CSCD 北大核心 2024年第4期1185-1197,共13页
针对传统算法存在的步长调整及耦合点选择问题,该文提出基于子循环自适应串行交错(SCAS)的时间匹配算法。首先,在步长调整方面,通过加入自适应(ATS)-启发式(HTS)混合变步长算法,解决步长无法实时调整的问题;然后,针对耦合点选择问题,该... 针对传统算法存在的步长调整及耦合点选择问题,该文提出基于子循环自适应串行交错(SCAS)的时间匹配算法。首先,在步长调整方面,通过加入自适应(ATS)-启发式(HTS)混合变步长算法,解决步长无法实时调整的问题;然后,针对耦合点选择问题,该文在传统常规串行交错(CSS)时间匹配算法及现有改进方案子循环常规串行交错(SCSS)的基础上,提出SCAS时间匹配算法,采用自适应方案确定计算时间窗及预定耦合点,并引入指数平滑法对其精度进行保证;最后,该文基于110 kV油浸式电力变压器建立二维瞬态单分区分匝绕组模型,并将所提算法与其他传统方法进行对比分析。结果表明:在精度方面,与传统CSS算法相比SCAS算法的流场及温度场最大平均相对误差均不超过0.45%,在可接受误差范围内;在效率方面,SCAS算法总体计算效率较CSS算法提高了近20倍。同时,为了说明所提算法的工程价值,该文搭建基于110 kV变压器绕组模型的温升实验平台,将SCAS时间匹配算法应用于该模型中,实验结果表明:在精度方面,SCAS算法与实验达到稳态时最大绝对误差为2.7 K;在计算效率上,本文所提算法的计算效率较传统算法提升约46倍,计算步数约为传统的1/47,减少了计算冗余。 展开更多
关键词 子循环自适应串行交错 混合变步长 二维瞬态流热耦合问题 快速计算方法 温升实验
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基于动态模态分解-自适应变步长油浸式电力变压器绕组瞬态温升快速计算方法 被引量:1
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作者 刘刚 郝世缘 +2 位作者 朱章宸 高成龙 刘云鹏 《电工技术学报》 EI CSCD 北大核心 2024年第12期3895-3906,共12页
为了改善当前油浸式电力变压器绕组瞬态温升计算过慢的问题,该文结合动态模态分解法和自适应变步长法提出了一种动态模态分解(DMD)-自适应变步长(ATS)快速计算方法。首先,该方法引入了动态模态分解算法,利用动态系统中前若干时步提取得... 为了改善当前油浸式电力变压器绕组瞬态温升计算过慢的问题,该文结合动态模态分解法和自适应变步长法提出了一种动态模态分解(DMD)-自适应变步长(ATS)快速计算方法。首先,该方法引入了动态模态分解算法,利用动态系统中前若干时步提取得到的变化特征,近似拟合其后一段时间内的系统变化,并通过选取主模态降低计算时间。其次,为了提高DMD算法性能,进一步提出结合ATS方法,通过自适应调整计算步长,提高瞬态计算效率;为了验证算法的计算精度和效率,建立了八分区分匝绕组数值传热模型并在此基础上将该文所提算法与仿真软件Fluent的计算结果进行对比,结果表明,在计算精度方面,二者结果几乎一致,计算误差最大不超过0.3 K;对于计算效率,该文算法的总计算时间为5.99 s,仅为Fluent总计算时间的1/89,且算法时间步数仅为Fluent的4.7%。最后,为了验证DMD-ATS算法的工程实用性,基于产品级油浸式电力变压器绕组结构搭建温升实验平台,并将所提算法计算结果与实验结果进行对比,结果表明所提算法在各测量线饼的误差均处在可接受的范围内,最大误差仅为4.57 K,且包含预处理时间在内的计算时间仅为69.14 s,计算时步仅需17步,较当前主流的计算方法效率有明显提高。综合算法的精度和效率,充分说明所提算法具有一定工程价值。 展开更多
关键词 动态模态分解 自适应变步长 主模态选取 瞬态温升问题
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严寒地区混合垂直通风猪舍环境质量评价 被引量:1
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作者 王朝元 马晓春 +3 位作者 党昊昱 方志伟 梁超 王钰 《农业工程学报》 EI CAS CSCD 北大核心 2024年第11期204-211,共8页
为探究垂直通风系统(屋顶与粪坑混合排风)在寒区猪舍中的适应性,该研究在秋冬季节对内蒙古某规模化猪舍的热湿与空气质量环境进行了实时连续监测,并根据测试结果对猪舍环境质量进行评价。结果表明:1)测试期间,舍内平均温度、相对湿度以... 为探究垂直通风系统(屋顶与粪坑混合排风)在寒区猪舍中的适应性,该研究在秋冬季节对内蒙古某规模化猪舍的热湿与空气质量环境进行了实时连续监测,并根据测试结果对猪舍环境质量进行评价。结果表明:1)测试期间,舍内平均温度、相对湿度以及氨气(NH_(3))、二氧化碳(CO_(2))、总悬浮颗粒物(total suspended particulate, TSP)浓度分别为22.7℃、59.6%、6.5 mg/m^(3)、2 200 mg/m^(3)、2 915μg/m^(3),舍内通风量为0.34~0.39 m^(3)/(h·kg),各环境指标基本满足生产环境阈值要求;保育期间舍内有效环境温度范围为27.1~30.7℃,存在轻度热应激情况,占总监测时间的12.9%;2)舍内温度、相对湿度与NH_(3)、CO_(2)、TSP浓度空间分布不均匀系数分别为0.01、0.15、0.45、0.03、0.15,各环境参数空间分布均较为均匀;3)试验单元(U1、U3)猪的平均日增质量、料重比与死淘率分别842和818 g/d、2.68和2.79、1.68%和1.31%,生产性能良好。综上,不设吊顶的侧墙进风,屋顶与粪坑混合排风的垂直通风系统,总体上能够满足严寒地区猪舍秋冬季热湿环境与空气质量调节需求,保证良好的生产性能。 展开更多
关键词 通风 温度 相对湿度 猪舍 适应性 热湿环境 空气质量
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