检索结果-南通市图书馆

concentrations of Heavy Metals in Suburban Horticultural Soils and Their Uptake by Artemisia selengensis

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2015年第6期25卷 878-887页

作者： cUI Xu SUN Xulei hu Pengjie YUAN cheng LUO Yongming WU Longhua peter cHRISTIE Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences University of chinese Academy of Sciences college of Resources and Environment Shanxi Agricultural University Key Laboratory of coastal Zone Environmental Processes Yantai Institute of Coastal Zone ResearchChinese Academy of Sciences

A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from roots to different plant parts in a representative vegetable production area in the Baguazhou Island, a suburb of Nanjing city, East china. The arithmetic mean values of total cd, cr,cu, Ni, Pb, and Zn concentrations in the soils were 0.314, 133, 41.0, 58.0, 31.8, and 114 mg kg-1, respectively. All of these values were above the topsoil background values in the Nanjing area. Multivariate and geostatistical analyses showed that soil cd contamination was derived mainly from agricultural practices. In contrast, cu and Zn were derived mainly from soil parent materials and Pb from atmospheric deposition from highway gasoline stations. Artemisia selengensis, a locally important specialty vegetable, accumulated heavy metals primarily in the edible leaves. The general distribution of heavy metal concentrations in this plant species showed that the highest occurred in the leaves, intermediate in the stems and lowest in the roots. cd had the highest concentration factor(root-to-soil ratio) and may pose increased health risks in the future to the local population through the consumption of contaminated vegetables.

关键词： concentration factor plant uptake pollution source spatial distribution translocation factor vegetable

Parameter identification and generality analysis of photovoltaic module dual-diode model based on artificial hummingbird algorithm

在线全文

学校读者我要写书评

暂无评论

clean Energy 2023年第6期7卷 1219-1232页

作者： Zhen Li Jianke hu Yifeng Han Hefeng Li Jun Wang peter D.Lund Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology School of Energy&EnvironmentSoutheast UniversityNanjing 210096China Powerchina huadong Engineering corporation Limited No.201 Gaojiao RoadHangzhou 311122China School of Science Aalto UniversityFI-00076Aalto(Espoo)Finland

The aim of this study is to propose a photovoltaic(PV)module simulation model with high accuracy under practical working conditions and strong applicability in the engineering field to meet various PV system simulation *** previous model-building methods,this study combines the advantages of analytical and metaheuristic ***,the applicability of various metaheuristic algorithms is comprehensively compared and the seven parameters of the PV cell under standard test conditions are extracted using the double diode model,which verifies that the artificial hummingbird algorithm has higher accuracy than other ***,the seven parameters under different conditions are corrected using the analytical *** terms of the correc-tion method,the ideal factor correction is added on the basis of previous methods to solve the deviation between simulated data and measured data in the non-linear ***,the root mean squared error between the simulated current data and the measured current data of the proposed model under three different temperatures and irradiance is 0.0697,0.0570 and 0.0289 A,respectively.

关键词： photovoltaic modules dual-diode model parameter identification metaheuristic algorithms parameter correction

Quasi-variable Discount Rates and Market Volatility: An Empirical Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2023年第5期32卷 515-530页

作者： Pengju Zhao Wei Zhang Xi Wu peter c.coyte Economics and Management School Zhongyuan University of TechnologyZhengzhou450007China Economics and Management School Tianjin UniversityTianjin300072China Economics and Management School System and Industrial Engineering Research CentreZhongyuan University of TechnologyZhengzhou450007China Institute of Health Policy Management and Evaluation(HPME)School of Public HealthUniversity of TorontoTorontoM5R 0A3Canada

This paper proposes an assumption of quasi-variable discount rates to explain the excess volatility puzzle of stock market. Under the assumption, the ARMAX model is derived based on the ccAPM model and cRRA utility function to describe the linear relationship between the discount rate and the consumption growth rate. We conducted empirical research on this model using historical data of the US stock market. The results confirm a significantly negative relationship between consumption growth rate and discount rate. Subsequently, the results of Monte carlo simulation show that given the risk preference coefficient and dividend sequence, the rational expectations price fluctuation obtained under the assumption of quasivariable discount rate is the largest.

关键词： Stochastic discount factor market volatility dividend discount model ARMAX

Runx2 regulates peripheral nerve regeneration to promote Schwann cell migration and re-myelination

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第7期19卷 1575-1583页

作者： Rong hu Xinpeng Dun Lolita Singh Matthew c.Banton School of Traditional chinese Medicine Department of Traditional Chinese MedicineNanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina The co-innovation center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Faculty of Health University of PlymouthPlymouthUK

Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea ***,we analyzed Runx2expression following injury and found that it was specifically up-regulated in Schwann ***,using Schwann cell-specific Runx2 knocko ut mice,we studied peripheral nerve development and regeneration and found that multiple steps in the regeneration process following sciatic nerve injury were *** observed in Runx2 knoc kout mice include increased prolife ration of Schwann cells,impaired Schwann cell migration and axonal regrowth,reduced re-myelination of axo ns,and a block in macrophage clearance in the late stage of *** together,our findings indicate that Runx2 is a key regulator of Schwann cell plasticity,and therefore peripheral nerve ***,our study shows that Runx2 plays a major role in Schwann cell migration,re-myelination,and peripheral nerve functional recovery following injury.

关键词： macrophage clearance migration peripheral nerve injury regeneration re-myelination Runx2 Schwann cells

Evaluation of Haney-Type Surface ThermalBoundary conditions Using a coupledAtmosphere and Ocean Model

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2001年第3期18卷 355-375页

作者： peter c. chu 陈玉春吕世华 Department of Oceanography Naval Postgraduate School

A coupled atmosphere-ocean model developed at the Institute for Space Studies at NASA Goddard Space Flight center (Russell et al., 1995) was used to verify the validity of Haney-type surface thermal boundary condition, which linearly connects net downward surface heat fluxQ to air/sea temperature difference ΔT by a relaxation coefficientk. The model was initiated from the National centers for Environmental Prediction (NcEP) atmospheric observations for 1 December 1977, and from the National Ocean Data center (NODc) global climatological mean December temperature and salinity fields at 1°x 1° resolution. The time step is 7.5 minutes. We integrated the model for 450 days and obtained a complete model-generated global data set of daily mean downward net surface fluxQ, surface air temperatureT A, and sea surface temperatureT O. Then, we calculated the cross-correlation coefficients (ccc) betweenQ and ΔT. The ensemble mean ccc fields show (a) no correlation betweenQ and ΔT in the equatiorial regions, and (b) evident correlation (ccc≥0.7) betweenQ and ΔT in the middle and high latitudes. Additionally, we did the variance analysis and found that whenk=120 W m?2K?1, the two standard deviations, σQ and σκδT , are quite close in the middle and high latitudes. These results agree quite well with a previous research (chu et al., 1998) on analyzing the NcEP re-analyzed surface data, except that a smaller value ofk (80 W m?2K?1) was found in the previous study. Key words Air-sea coupled system - Ocean surface fluxes - Surface thermal boundary condition

关键词： Air-sea coupled system Ocean surface fluxes Surface thermal boundary condition

Microstructure evolution and interface structure of Al-40 wt% Si composites produced by high-energy ball milling

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第4期35卷 512-519页

作者： Yuanyuan chen Zhangping hu Yifei Xu Jiangyong Wang peter Schützendübe Yuan huang Yongchang Liu Zumin Wang School of Materials Science and Engineering Tianjin University Department of Physics Shantou University Max Planck Institute for Intelligent Systems

High silicon content Al-Si composites with a composition of Al-40 wt% Si were fabricated via a highenergy ball milling method. The microstructure evolution of Al-40 wt% Si milled powders and sintered composites has been thoroughly studied by scanning electron microscopy, X-ray diffraction, energydispersive spectrometry and high-resolution transmission electron microscopy. The mechanism of ball milling Al-40 wt% Si powders has been disclosed in detail: fracture mechanism dominating in the early stages, followed by the agglomeration mechanism, finally reaching the balance between the fragments and the agglomerates. It has been found that the average particle sizes of mixed Al-Si powders can be refined to the nanoscale, and the crystallite sizes of Al and Si have been reduced to 10nm and 62nm upon milling for 2h–50h, respectively. The finally formed Al-Si interfaces after ball milling for 50h are wellcohesive. A dense and homogenous Al-40 wt% Si composite have been achieved by solid-state sintering at550?c. The results thus provide an effective support for producing bulk nanostructured Al-Si composites.

关键词： Al-Si composites Interface structure High-energy ball milling Nanocrystalline powders

AN ANALYSIS FOR DIFFRAcTION OF FLEXURAL WAVES AND DYNAMIc STRESS cONcENTRATIONS IN THIcK PLATES WITH A cAVITY

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 1997年第2期10卷 167-178页

作者： hu, c Ma, XR huang, WH Liu, DK HARBIN INST TEcHNOL HARBIN 150001PEOPLES R CHINA HARBIN ENGN UNIV HARBIN 150001PEOPLES R CHINA

By using the complex variable method and conformal mapping, the diffraction of flexural waves and dynamic stress concentrations in thick plates with a cavity have been studied. A general solution of the stress problem of the thick plate satisfying the boundary conditions on the contour of an arbitrary cavity is obtained. By employing the orthogonal function expansion technique, the dynamic stress problem can be reduced to the solution of an infinite algebraic equation series. As an example, the numerical results for the dynamic stress concentration factor in thick plates with a circular, elliptic cavity are graphically presented. The numerical results are discussed.

关键词： thick plate diffraction of flexural waves dynamic stress concentration complex variable method conformal mapping

Role of inflammation and infection in the pathogenesis of human acute liver failure: clinical implications for monitoring and therapy

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2016年第26期22卷 5958-5970页

作者： Mhairi c Donnelly peter c Hayes Kenneth J Simpson Department of Hepatology and Scottish Liver Transplant Unit Royal Infirmary of Edinburgh

Acute liver failure is a rare and devastating clinical condition. At present, emergency liver transplantation is the only life-saving therapy in advanced cases, yet the feasibility of transplantation is affected by the presence of systemic inflammation, infection and resultant multiorgan failure. The importance of immune dysregulation and acquisition of infection in the pathogenesis of acute liver failure and its associated complications is now recognised. In this review we discuss current thinking regarding the role of infection and inflammation in the pathogenesis of and outcome in human acute liver failure, the implications for the management of such patients and suggest directions for future research.

关键词： Inflammation Neuroinflammation Acute liver failure Biomarker Infection

Fifty Years of Water Sensitive Urban Design, Salisbury, South Australia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2017年第4期11卷 63-72页

作者： John c. Radcliffe Declan Page Bruce Naumann peter Dillon cSIRO Land and Water Private Bag 2 Glen Osmond South Australia 5064 Australia city of Salisbury 12 James St Salisbury South Australia 5108 Australia

Australia has developed extensive policies and guidelines for the management of its water. The city of Salisbury, located within metropolitan Adelaide, South Australia, developed rapidly through urbanisation from the 1970s. Water sensitive urban design principles were adopted to maximise the use of the increased rim-off generated by urbanisation and ameliorate flood risk. Managed aquifer recharge was introduced for storing remediated low-salinity stormwater by aquifer storage and recovery （ASR） in a brackish aquiter for subsequent lrngatlon. Ibis paper outlines now a municipal government has progressively adopted principles of Water Sensitive Urban Design during its development within a framework of evolving national water policies. Salisbury＇s success with stormwater harvesting led to the formation of a pioneering w aterbusiness that includes linking projects from nine sites to provide a non-potable supply of 5 ×10^6 m^3 year. These installations hosted a number of applied research projects addressing well configuration, water quality, reliability and economics and facilitated the evaluation of its system as a potential potable water source. The evaluation showed that while untreated stonnwater contained contaminants, subsurface storage and end-use controls were sufficient to make recovered water sale for public open space irrigation, and with chlorination acceptable lbr third pipe supplies. Drinking water quality could be achieved by adding microfiltration, disinfection with UV and chlorination. The costs that would need to be expended to achieve drinking water safety standards were found to be considerably less than the cost of establishing dual pipe distribution systems. The full cost of supply was determined to be AUD$1.57 m ＂ for non-potable water for pubhc open space lrngatlon much cheaper than mares water, AUD $3.45 m at that time. Producing and storing potable water was found to cost AUDS1.96 to $2.24 m .

关键词： Managed Aquifer Recharge (MAR) Stormwater harvesting Water recycling drinking water Low impact development Water sensitive urban design