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Journal of Forestry Research 2024年第3期35卷 175-188页

作者： Niu Zhu Jinniu Wang Dongliang Luo Xufeng Wang Cheng Shen Ning Wu Ning Zhangg Binghui Tian Aihong Gai Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041People's Republic of China College of Resources and Environmental Sciences Gansu Agricultural UniversityLanzhou 730070People's Republic of China Mangkang Ecological Monitoring Station Tibet Ecological Security Barrier Ecological Monitoring NetworkQamdo 854500People's Republic of China Northwest Institute of Eco Environmental Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China

Evapotranspiration is an important parameter used to characterize the water cycle of ecosystems.To under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qinghai-Tibet Plateau,an open-path eddy covariance system was set up to monitor the forest from November 2020 to October 2021 in a core area of the Three Parallel Rivers in the Qing-hai-Tibet Plateau.The results show that the evapotranspira-tion peaked daily,the maximum occurring between 11:00 and 15:00.Environmental factors had significant effects on evapotranspiration,among them,net radiation the greatest(R^(2)=0.487),and relative humidity the least(R^(2)=0.001).The energy flux varied considerably in different seasons and sensible heat flux accounted for the main part of turbulent energy.The energy balance ratio in the dormant season was less than that in the growing season,and there is an energy imbalance at the site on an annual time scale.

关键词： Evapotranspiration energy balance Subalpine forest Three Parallel Rivers region Southeast Qinghai-Tibet Plateau

Comparison of mesophilic and thermophilic anaerobic digestions of thermal hydrolysis pretreated swine manure: Process performance,microbial communities and energy balance

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Journal of Environmental Sciences 2023年第4期126卷 222-233页

作者： Xiaohui Liu Changmin Lee Jae Young Kim Department of Civil and Environmental Engineering Seoul National UniversitySeoul 08826Korea

Anaerobic digestion (AD) of swine manure (SM) commonly shows low biogas output and unsatisfactory economic performance. In this study, thermophilic AD (TAD, 50±1℃) was combined with thermal hydrolysis pretreatment (THP, 170℃/10 bar), to investigate its potential for maximizing biogas yield, securing successful digestion and microbial diversity, as well as improving energy balance. Four lab-scale continuously stirred tank reactors were operated for 300 days and compared with each other, i.e., reactor 1 (raw SM fed in mesophilic AD:RSM-MAD), reactor 2 (THP-treated SM fed in MAD:TSM-MAD), reactor 3 (RSM-TAD),and reactor 4 (TSM-TAD). The results showed that THP was efficient to increase methane production of SM, TSM-TAD mode led to the highest methane yield (129.8±40.5 mL-CH_(4)/gVS/day) among the tests (p 700 mg/L) or volatile fatty acids (> 6000 mg/L) accumulation compared with MAD in start-up phase, TSM-TAD treatment mode behaved a sustainable digestion process in a long-term operation. For TSM-TAD scenario, higher Shannon–Weaver (3.873) and lower Simpson index (0.061) indicated this mode ensured and enlarged the diversity of bacteria communities. Phylum Bathyarchaeota was dominant (59.3%-90.0%) in archaea community,followed by Euryarchaeota in the four reactors. RSM-MAD treatment mode achieved the highest energy output (4.65 GJ/day), TSM-TAD was less effective (-17.38 GJ/day) due to increased energy demands. Thus improving the energetic efficiency of THP units is recommended for the development of TSM-TAD treatment mode.

关键词： Thermal hydrolysis pretreatment Digestion temperature Process performances Microbial communities energy balance

Lycium barbarum Polysaccharides Promotes Mitochondrial Biogenesis and energy balance in NAFLD Cell Model

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Chinese Journal of Integrative Medicine 2022年第11期28卷 975-982页

作者： ZHANG Yan-nan GUO Yi-qiong FAN Yan-na TAO Xiu-juan GAO Qing-han YANG Jian-jun School of Public Healthand Management Ningxia Medical UniversityYinchuan(750004)China NingxiaKey Laboratory of Environmental Factors and Chronic Disease Control Yinchuan(750004)China Xi'an Chang'an South Road Community Health Service Center Xi'anYanta Hospital of Chinese MedicineXi'an(710000)China

Objective:To explore the protective effect and underlying mechanism of Lycium barbarum polysaccharides(LBP)in a non-alcoholic fatty liver disease(NAFLD)cell model.Methods:Normal human hepatocyte LO2 cells were treated with 1 mmol/L free fatty acids(FFA)mixture for 24 h to induce NAFLD cell model.Cells were divided into 5 groups,including control,model,low-,medium-and high dose LBP(30,100and 300μg/mL)groups.The monosaccharide components of LBP were analyzed with high performance liquid chromatography.Effects of LBP on cell viability and intracellular lipid accumulation were assessed by cell counting Kit-8 assay and oil red O staining,respectively.Triglyceride(TG),alanine aminotransferase(ALT),aspartate aminotransferase(AST),adenosine triphosphate(ATP)and oxidative stress indicators were evaluated.energy balance and mitochondrial biogenesis related mRNA and proteins were determined by quantitative real-time polymerase chain reaction and Western blot,respectively.Results:Heteropolysaccharides with mannose and glucose are the main components of LBP.LBP treatment significantly decreased intracellular lipid accumulation as well as TG,ALT,AST and malondialdehyde levels(Penergy balance in NAFLD cell model.

关键词： Lycium barbarum polysaccharides non-alcoholic fatty liver disease mitochondrial biogenesis energy balance Chinese medicine

Stability Improvement for One Cycle Controlled Boost Converters Based on energy balance Principle

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Chinese Journal of Electronics 2023年第6期32卷 1293-1303页

作者： WANG Lei WU Qinghua MA Wei TANG Wenhu Guangzhou Maritime University South China University of Technology (SCUT) Chongqing University of Science and Technology

Boost converters with one cycle control(OCC) are prone to exhibit oscillations as the Hopf bifurcation, which may degrade performances and limit the parameter stable region of converters. This work proposed a novel control strategy for suppressing such bifurcations and enlarging the parameter stability region of the boost system on the basis of the principle of energy balance in the circuit. Through analyzing of the stability and bifurcation condition, the results reflect that, the energybased OCC can adjust the poles of the system transfer function, which ensures the stable operation of the system in an extended range of circuit parameters. Moreover,the orders of the transfer function will not be increased by such adjustments, thus the computational complexity of the transfer function will be increased. The theoretical analysis demonstrates the ability of the energy-based OCC for suppressing the bifurcations and enlarging the stable region of the system parameters. The results by simulation and experiment further prove the effectiveness of the proposed control strategy.

关键词： Boost converter Dynamic average-value model Bifurcation energy balance

energy balance in DC Arc Plasma Melting Furnace

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Plasma Science and Technology 2009年第2期11卷 206-210页

作者：赵鹏孟月东遇鑫遥陈龙威江贻满倪国华陈明周 Institute of Plasma Physics Chinese Academy of Sciences

In order to treat hazardous municipal solid waste incinerator＇s （MSWI） fly ash, a new DC arc plasma furnace was developed. Taking an arc of 100 V/1000 A DC as an example, the heat transfer characteristics of the DC arc plasma, ablation of electrodes, heat properties of the fly ash during melting, heat transfer characteristics of the flue gas, and heat loss of the furnace were analyzed based on the energy conservation law, so as to achieve the total heat information and energy balance during plasma processing, and to provide a theoretical basis for an optimized design of the structure and to improve energy efficiency.

关键词： DC arc thermal plasma fly ash energy balance

Attribution of Biases of Interhemispheric Temperature Contrast in CMIP6 Models

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Advances in Atmospheric Sciences 2024年第2期41卷 325-340页

作者： Shiyan ZHANG Yongyun HU Jiankai ZHANG Yan XIA Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China School of Systems Science Beijing Normal UniversityBeijing 100875China

One of the basic characteristics of Earth's modern climate is that the Northern Hemisphere(NH) is climatologically warmer than the Southern Hemisphere(SH). Here, model performances of this basic state are examined using simulation results from 26 CMIP6 models. Results show that the CMIP6 models underestimate the contrast in interhemispheric surface temperatures on average(0.8 K for CMIP6 mean versus 1.4 K for reanalysis data mean), and that there is a large intermodel spread, ranging from -0.7 K to 2.3 K. A box model energy budget analysis shows that the contrast in interhemispheric shortwave absorption at the top of the atmosphere, the contrast in interhemispheric greenhouse trapping, and the crossequatorial northward ocean heat transport, are all underestimated in the multimodel mean. By examining the intermodel spread, we find intermodel biases can be tracked back to biases in midlatitude shortwave cloud forcing in AGCMs. Models with a weaker interhemispheric temperature contrast underestimate the shortwave cloud reflection in the SH but overestimate the shortwave cloud reflection in the NH, which are respectively due to underestimation of the cloud fraction over the SH extratropical ocean and overestimation of the cloud liquid water content over the NH extratropical continents.Models that underestimate the interhemispheric temperature contrast exhibit larger double ITCZ biases, characterized by excessive precipitation in the SH tropics. Although this intermodel spread does not account for the multimodel ensemble mean biases, it highlights that improving cloud simulation in AGCMs is essential for simulating the climate realistically in coupled models.

关键词： interhemispheric temperature contrast energy balance shortwave cloud forcing ITCZ CMIP6 AGCM

Effect of reduced energy density of close-up diets on dry matter intake,lactation performance and energy balance in multiparous Holstein cows

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Journal of Animal Science and Biotechnology 2015年第1期6卷 47-54页

作者： Wenming Huang Yujia Tian Yajing Wang Aminamu Simayi Amingguli Yasheng Zhaohai Wu Shengli Li Zhijun Cao State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University

energy intake prepartum is critically important to health, milk performance, and profitability of dairy cows. The objective of this study was to determine the effect of reduced energy density of dose-up diets on dry matter intake （DMI）, lactation performance and energy balance （EB） in multiparous Holstein cows which were housed in a free-stall barn and fed for ad libitum intake. Thirty-nine dry cows were blocked and assigned randomly to three groups fed a high energy density diet [HD, n = 13; 6.8 MJ of net energy for lactation （NEL）/kg; 14.0% crude protein （CP） ], or a middle energy density diet （MD, n = 13; 6.2 MJ NEh/kg; 14.0% CP）, or a low energy density diet （LD, n = 13; 5.4 MJ NEh/kg; 14.0% CP） from d 21 before expected day of calving. After parturition, all cows were fed the same lactation diet to d 70 in milk （DIM）. The DMI and NEE intake prepartum were decreased by the reduced energy density diets （P 〈 0.05）. The LD group consumed 1.3 last 24 h before calving. The milk yield and the postpartum kg/d （DM） more diet compared with HD group in the DMI were increased by the reduced energy density diet prepartum （P 〈 0.05）. The changes in BCS and BW prepartum and postpartum were not affected by prepartum diets HD group had higher milk fat content and lower lactose content compared with LD group during the first 3 wk of lactation （P 〈 0.05）. The energy consumption for HD, MD and LD groups were 149.8%, 126.2% and 101.1 % of their calculated energy requirements prepartum （P 〈 0.05）, and 72.7%, 73.1% and 7.5.2% during the first 4 wk postpartum, respectively. In conclusion, the low energy density prepartum diet was effective in controlling NF_L intake prepartum, and was beneficial in increasing DMI and milk yield, and alleviating negative EB postpartum.

关键词： Dietary energy density Dry matter intake energy balance Lactation performance Transition cow

Effects of changes in precipitation on energy and water balance in a Eurasian meadow steppe

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Ecological Processes 2019年第1期8卷 225-239页

作者： Jingyan Chen Changliang Shao Shicheng Jiang Luping Qu Fangyuan Zhao Gang Dong Institute of Loess Plateau Shanxi UniversityTaiyuan 030006China National Hulunber Grassland Ecosystem Observation and Research Station&Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Vegetation Ecology Ministry of EducationNortheast Normal UniversityChangchun 130024China Forestry Post-Doctoral Station Forest Ecology Stable Isotope CenterForestry CollegeFujian Agriculture and Forestry UniversityFuzhou350002China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China School of Life Science Shanxi UniversityTaiyuan 030006China.

Introduction:Water such as precipitation is the most critical environment driver of ecosystem processes and functions in semi-arid regions.Frequency and intensity of drought and transient waterlogging are expected to increase in the meadow steppe in northeastern China.Using a 4-year dataset of eddy covariance flux measurements,ground measurements of biomass,phenology,and meteorological conditions,we investigated the changes in energy fluxes at multiple temporal scales and under different precipitation regimes.Results:The meadow steppe was latent heat(LE)dominated when soil water content was>0.3 m3 m−3,but switched to sensible heat(H)dominated status when soil water content fell below 0.3 m3 m−3.LE dominated the energy exchange of the meadow grasslands on a yearly basis.Intensive precipitation had a profound impact on water-energy balance that could reduce the damages of drought by elevating deep soil moisture.The influence of LE on waterlogging depended on timing,with increased LE at the beginning of growing season and decreased LE after waterlogging.Spring and summer droughts resulted in different energy partitioning between latent and sensible heat energies,with spring drought dramatically decreased the LE fraction due to the change in water.In contrast,summer drought had little impact on LE due to the sufficient water input from large precipitation events at the beginning of the growing season.Conclusions:There existed great seasonal and interannual variabilities in energy balance and partitioning in the meadow steppe over the 4-year study period,which were strongly influenced by changes in precipitation.The water loss through latent heat was more sensitive to spring drought than to summer drought,while summer drought had negligible impact on LE.Waterlogging contributed to LE by enhancing its values during and after the waterlogged periods at the beginning of the growing season in a dry year,but lowering its value after the waterlogged periods in growing season.

关键词： energy balance energy partition Precipitation change Eddy covariance Drought

The energy balance of Plasma in a Coaxial Plasma Opening Switch

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Plasma Science and Technology 2006年第6期8卷 656-660页

作者：徐翔王友年 State Key Lab of Materials Modification by Electron Ion and Laser BeamsDepartment of PhysicsDalian University of TechnologyDalian 116023China

The two-dimensional energy balance in a coaxial plasma opening switch （POS） is studied based on the single-fluid magnetohydrodynarnic （MHD） equations coupled with the generalized Ohm＇s law. The energy transfers between the plasma and the magnetic field are considered during the penetration of the magnetic field as the Ohmic heating is included in the energy-balance equation. The focus is on the energy partition between the magnetic-field energy and the dissipated magnetic-field energy in a high-density POS with different rise-in-time electric currents at the generator boundary. The simulation code is tested in two cases： the constant-in-time current case and the linear rise-in-time current case. For the sinusoidally rise-in-time current similar to that of the experiments, it is shown that at the end of the conduction phase the dissipated magnetic-field energy is 36.5% of the input electromagnetic energy, which is consistent with the experimental results.

关键词： plasma opening switch energy balance magnetohydrodynamic （MHD） simulation

A Rendezvous Mechanism for energy balance and Link Quality in WSNs

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Wuhan University Journal of Natural Sciences 2018年第2期23卷 103-110页

作者： ZHU Yujun MEI Jie ZHAO Dadong FANG Qun School of Mathematics & Computer Science Anhui Normal University

Quorum System is a good method to assist the design of sensors of the wake-up scheduling mechanism. However, there are some problems about idle rendezvous and poor link quality when the sensor performs a sensing task according to the Quorum System. In order to improve the efficiency of the sensors and reduce energy consumption, a new rendezvous mechanism is proposed. The use of energy and the link quality between sensors are considered from a global perspective. It can not only ensure the rendezvous opportunity among sensors, but also balance the residual energy of the sensors, so it can improve the energy-saving efficiency of traditional Quorum System. According to the simulation, compared with the traditional Quorum System scheduling mechanism, the rendezvous mechanism proposed in this paper can effectively reduce the number of time-slots when the sensor is idle. Moreover, it also realizes the balance of the residual energy of the sensor and the link quality, which prolongs the life cycle of the wireless sensor network and improves the communication quality.

关键词： wireless sensor networks energy balance quorumsystem rendezvous link quality