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Kinetic Energy Budgets during the Rapid Intensification of Typhoon Rammasun (2014)
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作者 Xin QUAN Xiaofan LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期78-94,共17页
In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the ... In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the typhoon,the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere.The increase in the symmetric rotational kinetic energy in the mid and upper troposphere resulted from the upward transport of symmetric rotational kinetic energy from the lower troposphere.In the outer area,both typhoon and Earth’s rotation played equally important roles in the conversion from symmetric divergent kinetic energy to symmetric rotational kinetic energy in the lower troposphere.The decrease in the symmetric rotational kinetic energy in the upper troposphere was caused by the conversion to asymmetric rotational kinetic energy through the collocation of symmetric tangential rotational winds and the radial advection of asymmetric tangential rotational winds by radial environmental winds. 展开更多
关键词 Typhoon Rammasun(2014) rapid intensification kinetic energy budget symmetric and asymmetric winds divergent and rotational circulations environmental flows
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Influence of Climate and Daylength on the Activity Budgets of Feral Goats (Capra hircus) on the Isle of Rum, Scotland 被引量:5
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作者 石建斌 Robin Dunbar +1 位作者 李迪强 肖文发 《Zoological Research》 CAS CSCD 北大核心 2006年第6期561-568,共8页
Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainf... Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainfall) and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats' activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats. 展开更多
关键词 WEATHER Activity budget DAYLENGTH Feral goat Rum Island
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Diurnal activity rhythms and time budgets of captive Qinling golden takin(Budorcas taxicolor bedfordi) in the Qinling Mountains,Shaanxi,China 被引量:2
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作者 陈炜 申琦 +2 位作者 马清义 潘广林 雷初朝 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期149-152,共4页
In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00... In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00 am to 4:00 pm in July). The behavioral ethnogram was identified through observation at the sampling site, with the behaviors of golden takin recorded at 5 min interval using instantaneous scannable sampling method. The results indicated that the resting of golden takin took an important part in the daylight activities. Meanwhile, drinking and urinating and defecating were 1.92 and 0.54 and 0.92 times per head per day. Ambient temperature had a strong effect on the diurnal activity rhythms of golden takin. The diurnal activity rhymes were affected by ages of the animals effectively, which was expressed through differentiation of the time budgets. Moreover, different individuals in the same population showed some non-synchronously activity rhythms. 展开更多
关键词 CAPTIVITY Diurnal activity rhythm Golden takin Budorcas taxicolor bedfordi Time budget
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Pumping-induced Well Hydraulics and Groundwater Budget in a Leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties
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作者 ZHUANG Chao LÜChenyang +5 位作者 YAN Long LI Yabing ZHOU Zhifang WANG Jinguo DOU Zhi Walter A.ILLMAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期477-490,共14页
In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is... In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical analysis.Analytical investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard depletion.Locations of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater budget.In the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer drawdown.When using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage. 展开更多
关键词 HYDROGEOLOGY AQUITARD vertical heterogeneity semi-analytical solution well hydraulics groundwater budget
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Westerlies Affecting the Seasonal Variation of Water Vapor Transport over the Tibetan Plateau Induced by Tropical Cyclones in the Bay of Bengal
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作者 Xiaoli ZHOU Wen ZHOU +3 位作者 Dongxiao WANG Qiang XIE Lei YANG Qihua PENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期881-893,共13页
This study investigates the activity of tropical cyclones(TCs)in the Bay of Bengal(BOB)from 1979 to 2018 to discover the mechanism affecting the contribution rate to the meridional moisture budget anomaly(MMBA)over th... This study investigates the activity of tropical cyclones(TCs)in the Bay of Bengal(BOB)from 1979 to 2018 to discover the mechanism affecting the contribution rate to the meridional moisture budget anomaly(MMBA)over the southern boundary of the Tibetan Plateau(SBTP).May and October–December are the bimodal phases of BOB TC frequency,which decreases month by month from October to December and is relatively low in May.However,the contribution rate to the MMBA is the highest in May.The seasonal variation in the meridional position of the westerlies is the key factor affecting the contribution rate.The relatively southern(northern)position of the westerlies in November and December(May)results in a lower(higher)contribution rate to the MMBA.This mechanism is confirmed by the momentum equation.When water vapor enters the westerlies near the trough line,the resultant meridional acceleration is directed north.It follows that the farther north the trough is,and the farther north the water vapor can be transported.When water vapor enters the westerlies from the area near the ridge line,for Type-T(Type-R)TCs,water vapor enters the westerlies downstream of the trough(ridge).Consequently,the direction of the resultant meridional acceleration is directed south and the resultant zonal acceleration is directed east(west),which is not conducive to the northward transport of water vapor.This is especially the case if the trough or ridge is relatively south,as the water vapor may not cross the SBTP. 展开更多
关键词 tropical cyclone Tibetan Plateau Bay of Bengal moisture budget weste
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A tensile wearable SHF antenna with efficient communication in defense beacon technology
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作者 Pooja Naresh Bhatt Rashmi Pandhare 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期198-210,共13页
The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture wi... The study projects a flexible and compact wearable pear-shaped Super High Frequency(SHF)antenna that can provide detailed location recognition and tracking applicable to defense beacon technology.This mini aperture with electrical dimensions of 0.12λ_(0)×0.22λ_(0)×0.01λ_(0)attains a vast bandwidth over 3.1-34.5 GHz Super High Frequency(SHF)frequency band at S_(11)≤-10 dB,peak gain of 7.14 dBi and proportionately homogeneous radiation pattern.The fractional bandwidth(%BW)acquired is 168%that envelopes diversified frequency spectrum inclusive of X band specifically targeted to all kinds of defense and military operations.The proposed antenna can be worn on a soldier's uniform and hence the Specific Absorption Rate simulation is accomplished.The Peak SAR Value over 1 g of tissue is 1.48 W/kg and for 10 g of tissue is 0.27 W/kg well under the safety standards.The flexibility is proven by analyzing the full electromagnetic simulations for various bending conditions.Time response analysis is attained with its Fidelity Factor and Group Delay.Communication excellence is determined using Link Budget Analysis and it is seen that margin at 100 Mbps is 62 m and at 200 Mbps is 59 m.Prototype is fabricated along with experimental validation.All the results show harmony in shaping the antenna to provide critical situational awareness and data sharing capabilities required in defense beacon technology for location identification. 展开更多
关键词 COMPACT Defense beacon technology Link budget SAR Time domain WEARABLE
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Ultra-low loss silicon nitride becomes even cooler
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作者 Dawn T.H.Tan Xavier X.Chia 《Light(Science & Applications)》 SCIE EI CSCD 2024年第10期1997-1999,共3页
Ultra-low loss silicon nitride realized using deuterated precursors and low thermal budgets well within backend-of-line CMOS processing may accelerate widespread proliferation of their use.
关键词 low BUDGET NITRIDE
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Description of the Cover Picture
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《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第1期I0001-I0001,共1页
The cover picture is taken from the article “Improved scatter search algorithm for multi-skilled personnel scheduling of ship block painting ”. Ship painting operation has very strict processing time requirements,wh... The cover picture is taken from the article “Improved scatter search algorithm for multi-skilled personnel scheduling of ship block painting ”. Ship painting operation has very strict processing time requirements,which play a very important role in shipbuilding. Focuses on the optimization method for multi-skilled painting personnel scheduling,the budget working time analysis is carried out considering the influence of operating area,difficulty of spraying area,multi-skilled workers. 展开更多
关键词 PAINTING FOCUS BUDGET
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Freshening of the Intermediate Waters in the Northern South China Sea over the Past Six Decades
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作者 陈栩洋 王东晓 +2 位作者 舒业强 成里京 范双双 《Journal of Tropical Meteorology》 SCIE 2024年第1期42-50,共9页
The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the... The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the long-term changes in the intermediate water in the SCS have not been thoroughly studied due to limited data,particularly in relation to its thermodynamic variations.This study utilized reanalysis data products to identify a 60-year trend of freshening in the intermediate waters of the northern South China Sea(NSCS),accompanied by an expansion of low-salinity water.The study also constructed salinity budget terms,including advection and entrainment processes,and conducted an analysis of the salinity budget to understand the impacts of external and internal dynamic processes on the freshening trend of the intermediate water in the NSCS.The analysis revealed that the freshening in the northwest Pacific Ocean and the intensification of intrusion through the Luzon Strait at intermediate levels are the primary drivers of the salinity changes in the NSCS.Additionally,a weakened trend in the intensity of vertical entrainment also contributes to the freshening in the NSCS.This study offers new insights into the understanding of regional deep sea changes in response to variations in both thermodynamics and oceanic dynamic processes. 展开更多
关键词 freshening South China Sea salinity of the intermediate water salinity budget analysis Luzon Strait transport
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Roaming Where He Wants To Becoming a digital nomad in Bangkok
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作者 Huang Jiangqin 《China Report ASEAN》 2024年第5期50-53,共4页
What makes an ideal life?For many,it’s escaping crowded and expensive big cities and the accompanying long,exhausting commutes to settle in a beautiful,warm,and budget-friendly city,or hitting the road and going else... What makes an ideal life?For many,it’s escaping crowded and expensive big cities and the accompanying long,exhausting commutes to settle in a beautiful,warm,and budget-friendly city,or hitting the road and going elsewhere anytime you want.No alarm clocks,no punching in for work,no pressure from bosses-do a little work and then enjoy your life.This is the life for many digital nomads. 展开更多
关键词 beautiful BUDGET settle
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Link Budget and Enhanced Communication Distance for Ambient Internet of Things
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作者 YANG Yibing LIU Ming +2 位作者 XU Rongtao WANG Gongpu GONG Wei 《ZTE Communications》 2024年第1期16-23,共8页
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t... Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m. 展开更多
关键词 ambient IoT(AIoT) B5G backscatter communication link budget low-noise amplifier(LNA) Release 19 tag chip sensitivity upper bounds
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Optimization Analysis of Comprehensive Budget Management from the Perspective of Digital Restructuring:Taking a Water Company as an Example
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作者 Zhongjie Wang 《Proceedings of Business and Economic Studies》 2024年第4期23-31,共9页
This article takes water enterprises as the research object,exploring the organic combination of comprehensive budget management under the trend of digitalization and digital technology in the new era,as well as the p... This article takes water enterprises as the research object,exploring the organic combination of comprehensive budget management under the trend of digitalization and digital technology in the new era,as well as the process of management system reform.Introduce the current status of its budget management work,comprehensively analyze the architecture and operation mode of the current comprehensive budget management system of water enterprises,and evaluate and analyze the overall situation and shortcomings of its budget management system based on financial data such as budget formulation and execution.From the perspective of digital restructuring and upgrading of comprehensive budget management work,corresponding countermeasures are proposed to make up for the shortcomings and suggestions for the future development of the enterprise’s comprehensive budget. 展开更多
关键词 DIGITIZATION Comprehensive budget ACHIEVEMENTS Water company
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Discussion on Construction Project Cost Budget Settlement Review
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作者 Hongfeng Liu Yumin Yuan 《Journal of Architectural Research and Development》 2024年第1期43-48,共6页
Construction project cost control involves many complex contents,forming a large amount of data information.If the processing method is unreasonable,it will likely affect the cost control efficiency.Therefore,in the c... Construction project cost control involves many complex contents,forming a large amount of data information.If the processing method is unreasonable,it will likely affect the cost control efficiency.Therefore,in the current construction project management,the review of project cost budget settlement is the focus to solve the cost management problems of construction projects and promote the development of the construction industry.This article mainly analyzes the influencing factors and current situation of construction project cost budget settlement review,and based on this,it explores the project cost budget settlement review strategy to promote the healthy development of construction project cost work. 展开更多
关键词 Construction project COST Budget settlement Review strategy
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Analysis of Hospital Budget Management Control Based on Smart Hospital
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作者 Yuqi Chen 《Journal of Clinical and Nursing Research》 2024年第5期169-173,共5页
Hospitals are crucial healthcare facilities where patients seek treatment,and effective budget management within hospitals significantly impacts their operational efficiency and financial performance.In the age of inf... Hospitals are crucial healthcare facilities where patients seek treatment,and effective budget management within hospitals significantly impacts their operational efficiency and financial performance.In the age of information technology and advanced healthcare solutions,the emergence of smart hospitals represents a new trend in the medical industry’s evolution.Leveraging modern information technology can enhance the development of hospital IT systems and drive budget management toward greater intelligence.This paper begins by analyzing the influence of smart hospitals on hospital budget control.It then examines the current state of budget management control within smart hospitals.Finally,it proposes several strategies for budget management control in smart hospitals,aiming to provide guidance for relevant stakeholders. 展开更多
关键词 Smart hospital Hospital management Budget management Financial control Control strategies
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Discussion on Cost Budgeting and Cost Control Strategies for Prefabricated Construction Projects
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作者 Congzi Cheng 《Journal of Architectural Research and Development》 2024年第4期17-23,共7页
In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of... In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of the prefabricated construction industry is constantly accelerating.To effectively ensure the economic benefits of engineering projects,it is necessary to comprehensively strengthen cost budgeting and cost control.This article analyzes the cost budget of prefabricated construction projects,introduces the application advantages of prefabricated construction,and proposes specific cost budgeting and cost control measures,hoping to provide some reference for relevant researchers. 展开更多
关键词 Prefabricated building Engineering cost budget Cost control
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Differences between Convective and Stratiform Precipitation Budgets in a Torrential Rainfall Event 被引量:5
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作者 Yongjie HUANG Yaping WANG Xiaopeng CUI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第5期495-509,共15页
Differences in rainfall budgets between convective and stratiform regions of a torrential rainfall event were investigated using high-resolution simulation data produced by the Weather Research and Forecasting(WRF) mo... Differences in rainfall budgets between convective and stratiform regions of a torrential rainfall event were investigated using high-resolution simulation data produced by the Weather Research and Forecasting(WRF) model. The convective and stratiform regions were reasonably separated by the radar-based convective–stratiform partitioning method, and the threedimensional WRF-based precipitation equation combining water vapor and hydrometeor budgets was further used to analyze the rainfall budgets. The results showed that the magnitude of precipitation budget processes in the convective region was one order larger than that in the stratiform region. In convective/stratiform updraft regions, precipitation was mainly from the contribution of moisture-related processes, with a small negative contribution from cloud-related processes. In convective/stratiform downdraft regions, cloud-related processes played positive roles in precipitation, while moisture-related processes made a negative contribution. Moisture flux convergence played a dominant role in the moisture-related processes in convective or stratiform updraft regions, which was closely related to large-scale dynamics. Differences in cloud-related processes between convective and stratiform regions were more complex compared with those in moisture-related processes.Both liquid-and ice-phase microphysical processes were strong in convective/stratiform updraft regions, and ice-phase processes were dominant in convective/stratiform downdraft regions. There was strong net latent heating within almost the whole troposphere in updraft regions, especially in the convective updraft region, while the net latent heating(cooling) mainly existed above(below) the zero-layer in convective/stratiform downdraft regions. 展开更多
关键词 CONVECTIVE RAINFALL STRATIFORM RAINFALL precipitation BUDGET UPDRAFT REGION downdraft REGION
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Activity budgets in a group of Sichuan snub-nosed monkeys in Shennongjia Nature Reserve,China 被引量:3
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作者 Yiming LI 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第3期173-179,共7页
We examined time allocation by Sichuan snub-nosed monkeys Rhinopithecus roxellana in the montane, temperate and highly seasonal forests of the Shennongjia Nature Reserve in China, in order to improve our understanding... We examined time allocation by Sichuan snub-nosed monkeys Rhinopithecus roxellana in the montane, temperate and highly seasonal forests of the Shennongjia Nature Reserve in China, in order to improve our understanding of the ecological and social influences on monkey behavior. We collected data on activity budgets in relation to food availability in a group of monkeys from July 2003 to September 2004 (except February 2004), using instantaneous scan samples. The monkeys spent 36.21% of daytime moving ( n = 21, 269 records), 24.39% foraging, 9.33% inactive, 11,7% performing social behaviors, and 18.38% performing other behaviors. There were seasonal and annual variations in the proportions of time devoted to some activities. These variations were largely attributed to seasonal or annual fluctuations in the distribution and quality of food resources. Adult males spent more time moving, searching, and displaying other behaviors, but less time feeding and performing social behaviors than adult females. Adults performed other behaviors more often and moving less often than juveniles. These differences in activity budgets may reflect fundamental differences in reproductive biology, parental investment, and development among the different age/sex classes [ Current Zoology 55 (3) : 173 - 179, 2009] . 展开更多
关键词 Activity budgets Seasonal food availability Age/sex classes Sichuan snub-nosed monkeys Rhinopithecus roxellana
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Historic changes in flux of matter and nutrient budgets in the Bohai Sea 被引量:3
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作者 LIU Sumei ZHANG Jing +1 位作者 GAO Huiwang LIU Zhe 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第5期81-97,共17页
Over the past four periods ( 1959--1960, 1982--1983, 1992--1993, and 1998--1999), the ecosystem of the Bohai Sea changed due to both a significant decrease of river water discharge from the Huanghe River and a reduc... Over the past four periods ( 1959--1960, 1982--1983, 1992--1993, and 1998--1999), the ecosystem of the Bohai Sea changed due to both a significant decrease of river water discharge from the Huanghe River and a reduction of precipitation. The shifts in nutrient chemistry could result in changes in the phytoplankton composition with an increased potential for non-diatom algal blooms. Simple box model was used to estimate the water - mass balance and nutrient budgets for the Bohai Sea. Water budgets indicate that the residual flow changed from out of the Bohai Sea before 1993, but became inflow to the Bohai Sea after then. The nutrient budgets developed indicate that the Bohai Sea was a sink for nutrients except for phosphate in 1959--1960 and 1982-- 1983 and for silicate in 1982--1983. Net water flow transports nutrients out of the Bohai Sea in 1959--1960, 1982--1983 and 1992--1993, but into the sea in 1998--1999 due to climate changes, such as precipitation and subsequent freshwater discharge. The residual fluxes of nutrients are minor relative to atmospheric deposition and riverine inputs. Conversions of phosphate values to carbon by stoichiometric ratios were used to predict that the system was net heterotrophic before 1982--1983 and net autotrophic after then. Nutrient budgets can explain the change of nutrient concentrations in the Bohai Sea except nitrates, which should include the surface runoff. 展开更多
关键词 freshwater discharge precipitation NUTRIENTS atmospheric deposition BUDGET Bohai Sea
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RO_(x) Budgets and O_(3) Formation during Summertime at Xianghe Suburban Site in the North China Plain 被引量:3
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作者 Min XUE Jianzhong MA +5 位作者 Guiqian TANG Shengrui TONG Bo HU Xinran ZHANG Xinru LI Yuesi WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第7期1209-1222,共14页
Photochemical smog characterized by high concentrations of ozone(O_(3)) is a serious air pollution issue in the North China Plain(NCP)region,especially in summer and autumn.For this study,measurements of O_(3),nitroge... Photochemical smog characterized by high concentrations of ozone(O_(3)) is a serious air pollution issue in the North China Plain(NCP)region,especially in summer and autumn.For this study,measurements of O_(3),nitrogen oxides(NO_(x)),volatile organic compounds(VOCs),carbon monoxide(CO),nitrous acid(HONO),and a number of key physical parameters were taken at a suburban site,Xianghe,in the NCP region during the summer of 2018 in order to better understand the photochemical processes leading to O_(3)formation and find an optimal way to control O_(3)pollution.Here,the radical chemistry and O_(3)photochemical budget based on measurement data from 1−23 July using a chemical box model is investigated.The daytime(0600−1800 LST)average production rate of the primary radicals referred to as RO_(x)(OH+HO2+RO2)is 3.9 ppbv h−1.HONO photolysis is the largest primary RO_(x)source(41%).Reaction of NO2+OH is the largest contributor to radical termination(41%),followed by reactions of RO2+NO2(26%).The average diurnal maximum O_(3)production and loss rates are 32.9 ppbv h−1 and 4.3 ppbv h−1,respectively.Sensitivity tests without the HONO constraint lead to decreases in daytime average primary RO_(x)production by 55%and O_(3)photochemical production by 42%,highlighting the importance of accurate HONO measurements when quantifying the RO_(x)budget and O_(3)photochemical production.Considering heterogeneous reactions of trace gases and radicals on aerosols,aerosol uptake of HO2 contributes 11%to RO_(x)sink,and the daytime average O_(3)photochemical production decreases by 14%.The O_(3)-NO_(x)-VOCs sensitivity shows that the O_(3)production at Xianghe during the investigation period is mainly controlled by VOCs. 展开更多
关键词 photochemical smog RO_(x)budgets O_(3)production rate O_(3)chemical regime
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COMPARATIVE STUDIES ON NITROGEN BUDGETS OF CLOSED SHRIMP POLYCULTURE SYSTEMS 被引量:3
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作者 齐振雄 李德尚 +1 位作者 张曼平 董双林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第3期233-242,共10页
April to October, 1997 comparative studies on the nitrogen budgets of closed shrimp polyculture systems showed that, in all the studied polyculture systems, nitrogen from feeds and fertilizers were the main input item... April to October, 1997 comparative studies on the nitrogen budgets of closed shrimp polyculture systems showed that, in all the studied polyculture systems, nitrogen from feeds and fertilizers were the main input items, which comprised 70.7%-83.9% of the total input nitrogen, 3.2%-7.4% of which was provided by nitrogen fixation. It was in monoculture enclosures (Y 4, Y 11 and Y 12) that the percentage reached the maximum value. The output nitrogen in harvested products comprised 10.8%-24.6% of total input nitrogen, and the highest percentage, 24.6%, was found in shrimp fish tagelus polyculture systems. In shrimp monoculture and shrimp fish polyculture systems, they were 19.1% and 21.9%, respectively. The nitrogen utilization efficiency was different and varied from 12.2% to 20.1%. The highest, 20.1%, was found in shrimp fish tagelus polyculture systems, and the average of 20.0% was found in shrimp tagelus polyculture systems. The lowest, 12.2%, was found in shrimp monoculture systems. All the nitrogen utilization efficiencies in shrimp fish systems or shrimp scallop systems seemed to be higher than that of the monoculture system, but they showed little statistical difference. The main outputs of nitrogen were found in sediment mud, and comprised 48.2%-60.8% of the total input, the lowest percentage was found in shrimp fish tagelus polyculture systems, and the highest percentage in shrimp scallop systems. During the experiment, nitrogen lost through denitrification and ammonia volatilization comprised 1.9%-6.2%, averaged 2.8%, of the total input, and the loss through seepage comprised 5.9%-8.9% of the total. The estimated nitrogen attached to the enclosure wall comprised 3.7%-13.3% of the total, and was highest in shrimp monoculture systems. Compared with the classic shrimp farming industry, the closed shrimp polyculture systems may improve the nitrogen utilization efficiency, and hence reduce the environmental impacts on coastal waters. The nitrogen discharging rates for all the studied polyculture systems ranged from 3.0% to 6.0% of total input nitrogen. 展开更多
关键词 nitrogen budget shrimp culture polyculture system
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