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Climate change, social unrest and dynastic transition in ancient China

Science Bulletin 2005年第2期50卷 137-144页

作者： jim Chiyung,LEE Fung Department of Geography University of Hong Kong Hong Kong China Department of Geography University of Hong Kong Hong Kong China

The evident connection between human evolu- tion and climatic changes has been concurred by scientists. Although many people are trying to forecast the impacts of climatic changes on our future society, there are not any studies to quantitatively scrutinize the interrelation between climatic changes and social developments by using historical data. In line with this knowledge gap, this study adopted a scientific approach to compare the paleoclimatic records with the historical data of wars, social unrests, and dynastic transitions in China spanned from the late Tang to Qing Dy- nasties. Results showed that war frequency in cold phases was much higher than that in mild phases. Besides, 70%— 80% of war peaks and most of the dynastic transitions and nationwide social unrests in China took place in cold phases. This phenomenon could be attributed to the diminishing thermal energy input in cold phases resulting in the fall of land-productivity and hence, the deficiency of livelihood re- sources across society. Accompanied with certain social cir- cumstances, this kind of ecological stress was transformed into wars and social unrests, followed by dynastic transitions in most of the cases. By closer examination, it was even found that war frequency was negatively correlated with tempera- ture anomaly series. As land carrying capacities vary from one climatic zone to another, the magnitude of war-tempera- ture association also differed among different geographic regions. It is suggested that climatic change was one of the most important factors in determining the dynastic cycle and alternation of war and peace in ancient China.

关键词： climatic change war social unrest dynastic cycle temperature anomaly.

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A new method for deriving broad-band polar motion geodetic excitations

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Geodesy and Geodynamics 2024年第5期 453页

作者： Wei Chen Jiesi Luo jim Ray Jiancheng Li

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A Novel Edge Computing Based Area Navigation Scheme

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Computers, Materials & Continua 2020年第12期65卷 2385-2396页

作者： Jianzhong Qi Qingping Song jim Feng School of Information Science and Technology North China University of TechnologyBeijing100144China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Science and Technology on Information Systems Engineering Laboratory Beijing Institute of Control and Electronic TechnologyBeijing100038China Amphenol Global Interconnect Systems San JoseCA 95131USA

The area navigation system,discussed in this paper,is composed of ground responders and a navigation terminal and can position a high-velocity aircraft and measure its *** navigation system is silent at ordinary *** sends out a request signal when positioning is required for an aircraft,and then the ground responders send a signal for resolving the *** the direct sequence spread spectrum and frequency hopping,the concealed communication mode is used in the whole communication process,with short communication pulses as much as possible,so the system has strong concealment and anti-interference *** the transmission delay is apparent in the response communication mode,there is a big error where the common navigation algorithm is used for the positioning and velocity measurement of a high-velocity *** this paper,a new algorithm is proposed,which can eliminate the influence of response communication delay on the positioning of a high-velocity moving target to realize the precise positioning and velocity measurement of a high-velocity aircraft.

关键词： Navigation pseudo-noise code ranging positioning velocity measurement edge computing

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Multivariate adaptive regression splines analysis for 3D slope stability in anisotropic and heterogenous clay

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 1052-1064页

作者： jim Shiau Van Qui Lai Suraparb Keawsawasvong School of Civil Engineering and Surveying University of Southern QueenslandToowoombaQueensland4350Australia Faculty of Civil Engineering Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet StreetDistrict 10Ho Chi Minh CityViet Nam Vietnam National University Ho Chi Minh City(VNU-HCM) Linh Trung WardThu Duc DistrictHo Chi Minh CityViet Nam Department of Civil Engineering Thammasat School of EngineeringThammasat UniversityPathumthaniBangkok12120Thailand

Little research can be found in relation to the stability of anisotropic and heterogenous soils in three *** this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and heterogenous clay using advanced upper and lower bounds finite element limit analysis(FELA).The obtained stability solutions are normalized,and presented by a stability number that is a function of three geometrical ratios and two material ratios,*** ratio,length ratio,slope angle,shear strength gradient ratio and anisotropic strength *** results are compared with experimental data in the literature,and charts are presented to cover a wide range of design *** the multivariate adaptive regression splines(MARS)analysis,the respective influence and sensitivity of each design parameter on the stability number and the failure mechanism are *** empirical equation is also developed to effectively estimate the stability number.

关键词： 3D undrained slope Limit analysis Anisotropy Heterogeneity

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Incineration of kitchen waste with high nitrogen in vortexing fluidized-bed incinerator and its NO emission characteristics

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Journal of Environmental Sciences 2013年第9期25卷 1841-1846页

作者： Feng Duan Chiensong Chyang Jiaruei Wen jim Tso School of Metallurgy and Resource Anhui University of Technology Department of Chemical Engineering Chung Yuan Christian University Research and Development Center for Environmental Technology Chung Yuan Christian University

Some municipal solid waste （MSW） can be used as the fuel. Combustion of MSW with high nitrogen content is successfully conducted in a lab-scale vortexing fluidized-bed incinerator （VFBI）. Pigskin with 16.5 wt.% nitrogen content was used to simulate the high nitrogen content kitchen waste, and silica sand was used as the bed material. The effects of operating conditions, such as the bed temperature, freeboard temperature, excess oxygen ratio, and static bed height on the CO and NO concentrations at the exit of combustor and cyclone were investigated. The experimental results show that the freeboard temperature is the most important factor for CO emission. The order of operating conditions impact on the NO emission is：（1） excess oxygen ratio; （2） bed temperature; （3） freeboard temperature; and （4） static bed height. Utilizing cyclone can significantly reduce the CO emission concentration when the CO concentration released from the freeboard is higher than 50 ppm. On the other hand, the cyclone has no significant effect on the NO emission. Despite having high nitrogen content, a low conversion from fuel-N to NO was attained. Compared with other types of combustors, VFBI reduces the CO and NO emission concentrations much better when burning MSW with high nitrogen content.

关键词： incineration high nitrogen content vortexing fluidized bed pollutant emission

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An integrated approach to improve the performance of lean–electrolyte lithium–sulfur batteries

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Journal of Energy Chemistry 2022年第4期31卷 585-592页

作者： Hualin Ye Jianguo Sun Yun Zhao jim Yang Lee Department of Chemical and Biomolecular Engineering National University of Singapore119260Singapore Department of Mechanical Engineering National University of Singapore117575Singapore

While the sulfur conversion reaction kinetics in Li–S batteries is nowadays improved by the use of appropriate electrocatalysts,it remains a challenge for the batteries to perform well under the lean electrolyte condition where polysulfide shuttle,electrode passivation and the loss of electrolyte due to side reactions,are *** challenges are addressed in this study by the tandem use of a polysulfide conversion catalyst and a redox–targeting mediator in a gel sulfur ***,the gel cathode reduces the polysulfide mobility and hence the polysulfide shuttle and the passivation of the lithium anode by the crossover *** redox mediator restrains the deposition of inactive sulfur species in the cathode thereby enabling the Fe–N and Co–N co–doped carbon catalyst to prolong its catalytic ***,the integrated catalytic system is able to increase the discharge capacity of high–loading (6.8 mg cm^(-2)) lean–electrolyte (4.0μL mg^(-1)) Li–S batteries from~630 to~1316 m Ah g^(-1),concurrently with an improvement of the cycle life (600 cycles with 46%capacity retention at 1.0 m A cm^(-2)).Redox mediator assisted catalysis in a gel cathode is therefore an effective strategy to extend the application of the sulfur conversion catalyst in lean electrolyte Li–S batteries.

关键词： Redox mediators Gel electrolytes Polysulfide catalysis Lean electrolyte Lithium–sulfur batteries

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Evaluation of fiber optic methane sensor using a smoke chamber

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International Journal of Mining Science and Technology 2018年第6期28卷 969-974页

作者： Mingming Li Thomas Dubaniewicz Heather Dougherty jim Addis National Institute for Occupational Safety and Health Pittsburgh Mining Research Division

This report presents the results of experiments to evaluate a prototype fiber optic methane monitor exposed to smoke using a smoke chamber to simulate atmospheric conditions in an underground coal mine after a fire or explosion. The experiments were conducted using test fires of different combustible sources commonly found in mines —douglas-fir wood, SBR belt, and Pittsburgh seam coal. The experiments were designed to assess the response of the fiber optic methane sensor to different contaminants,different contaminant levels and different contaminant durations produced from the test fires. Since the prototype methane monitor detects methane by measuring absorption at a specific wavelength, optical power at the absorption wavelength(1650 nm) was measured as a function of smoke concentration and duration. The other sensor response parameter-methane response times-were measured between smoke tests to assess the impact of soot accumulation on the sensor. Results indicate that the sensor screen effectively prevented smoke from obscuring the optical beam within the sensor head, with minimal impact on the system optical power budget. Methane response times increased with smoke exposure duration, attributed to soot loading on the protective screen.

关键词： Fiber optic Methane sensor Fires Optical power Response time

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Population Diversity of Puccinia graminis is Sustained Through Sexual Cycle on Alternate Hosts

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Journal of Integrative Agriculture 2014年第2期13卷 262-264页

作者： Yue Jin Matt Rouse jim Groth USDA-ARS Cereal Disease LaboratoryUniversity of MinnesotaSt.PaulMN 55108USA Colville WA 99114USA

A high degree of virulence diversity has been maintained in the population of Puccinia graminis f. sp. tritici （Pgt） in northwestern United States. Although Berberis vulgaris is present in the region and Pgt has been isolated from aecial infections on B. vulgaris, the population is too diverse to be explained by the limited presence of B. vulgaris alone. Since 2008, we have isolated P. graminis from aecial infections on fruits of Mahonia repens and Mahonia aquifolium from northwestern United States. These two native woody shrub species, widely distributed in western North America, were once classified as resistant to P. graminis based on artificial inoculations. By isolating P. graminis from aecia, we established that M. repens and M. aquifolium along with B. vulgaris （albeit infrequent） serve as the alternate hosts ofP. graminis in the region. The isolates of P. graminis from Mahonia of North America had diverse virulence patterns and most of the isolates could be differentiated on Morocco, Line E, Chinese Spring, Little Club, LMPG-6, Rusty, and other genotypes that are considered to be universally susceptible to most Pgt isolates. This discovery explained the persistence of virulence diversity of Pgt observed in isolates derived from uredinia on cereal crops in the region. In addition to cereal crops, uredinial stage of the P. graminis population is sustained by wild grasses, especially Elymus glaucus, a native grass sharing the same habitat with the rusted Mahonia spp. Although virulence to some important stem rust resistance genes was observed in some isolates derived from Mahonia of North America when tested against single stem rust resistance gene stocks, the overall virulence is very limited in these isolates. This is likely a result of limited selection pressure on the rust population. In contrast to northwestern United Sates, the Pgt population in east of the Rocky Mountains of North America has declined steadily with a single race, QFCSC, being predominant

关键词： Puccinia graminis f. sp. tritici wheat stem rust alternate host Mahonia aquifolium M. repens Berberis vulgaris

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Role of surfactant in the paradigm of ALI/ARDS

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Acta Pharmacologica Sinica 2003年第12期 164-165页

作者： jim LEWIS Canada Lawson Health Research Institute/St. Joseph’s Health Center London/Ontario N6A4V2 University of Western Ontario

ALI/ARDS is a devastating complication occurring in critically ill patients, and despite extensive research ettects over the last 30 years, current mortality remains unacceptably high at approxjmately 30% to 40%. Although several different insults can ultimately lead to ALI/ARDS, the clinical definition of this syndrome is relatively simple, and involves commmon physiologic criteria. Indeed, it was these criteria(hypoxemia and decreased lung compliance without heart failure) together with the pathologic similarities to infants with

关键词： Role of surfactant in the paradigm of ALI/ARDS In as on ALI of in

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Distinct strengths of mTORC1 control T-cell memory via transcriptional FOXO1 and metabolic AMPKα1 pathways in linear cell differentiation and asymmetric cell division models

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Cellular & Molecular Immunology 2022年第10期19卷 1073-1076页

作者： Junqiong Huang Scot Leary jim Xiang Cancer Research Cluster Saskatchewan Cancer AgencySaskatoonSKCanada Department of Oncology College of MedicineUniversity of SaskatchewanSaskatoonSKCanada Department of Blood Transfusion Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhouChina Department of Biochemistry Microbiology and ImmunologyCollege of MedicineUniversity of SaskatchewanSaskatoonSKCanada

CD8^(+)effector T(T_(E))cells play a critical role in immunity against *** response to a pathogenic stimulus,antigenpresenting cells(APCs)deliver three signals[via T-cell receptor(TCR),costimulation,and cytokines]to naive CD8^(+)T cells,stimulating their entry into a developmental program characterized by T-cell expansion followed by a contraction *** the contraction phase,90-95%of IL-7R^(-)CD62L^(-)KLRG1^(+)T_(E)cells undergo cell apoptosis.

关键词： FOXO1 immunity stimulation

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