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Review of regional carbon counting methods for the Chinese major ecological engineering programs

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Journal of Forestry Research 2016年第4期27卷 727-738页

作者： Ji Zheng Xiaohua Wei Yuanqiu Liu Guohua Liu Weifeng Wang Wenfei Liu College of Forestry Jiangxi Agricultural UniversityNanchang 330045 China University of British Columbia (Okanagan Campus) Kelowna BC V1V1VT Canada State Key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesBeijing 100085 China Inner Mongolia Academy of Forestry Science Hohhot 010010 China Research Institute of Ecology & Environmental Sciences Nanchang Institute of Technology Nanchang 330099 China

In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland Conversion Program, the Desertification Combating Program, and the Protection Forest System Construction Program. There is a growing need to quantify the contributions of these programs to regional carbon ***, the lack of widely accepted, robust methods is one of the key obstacles to quantification. The objective of this study was to review existing methods for quantifying regional carbon stocks and then recommend suitable ones for the Chinese ecological engineering programs. We expect that the recommended methods can be applied to elsewhere in the world where there are similar characteristics and objectives.

关键词： programs elsewhere vegetation contributions stocks Conversion forests obstacles biomass expect

Thermal activation of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height

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Chinese Physics B 2010年第9期19卷 548-558页

作者：茹国平俞融蒋玉龙阮刚 State Key laboratory of ASIC and System Department of MicroelectronicsFudan University

This paper investigates the thermal activation behaviour of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height by numerical simulation. The analytical Gaussian distribution model predicted that the I-vt curves may intersect with the possibility of the negative thermal activation of current, but may be contradictory to the thermionic emission mechanism in a Schottky diode. It shows that the cause of the unphysical phenomenon is related to the incorrect calculation of current across very low barriers. It proposes that junction voltage Vj, excluding the voltage drop across series resistance from the external bias, is a crucial parameter for correct calculation of the current across very low barriers. For correctly employing the thermionic emission model, Vj needs to be smaller than the barrier height Ф. With proper scheme of series resistance connection where the condition of Vj 〉 Ф is guaranteed, I-V T curves of an inhomogeneous Schottky diode with a Gaussian distribution of barrier height have been simulated, which demonstrate normal thermal activation. Although the calculated results exclude the intersecting possibility of I-V T curves with an assumption of temperature-independent series resistance, it shows that the intersecting is possible when the series resistance has a positive temperature coefficient. Finally, the comparison of our numerical and analytical results indicates that the analytical Gaussian distribution model is valid and accurate in analysing I-V-T curves only for small barrier height inhomogeneity.

关键词： Schottky diode barrier height inhomogeneity I-V-T thermal activation

Corrosion Behavior of AZ31 Magnesium Alloy in Highly Alkaline Environment

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 367-375页

作者： Somi Doja Lukas Bichler Simon Fan School of Engineering University of British ColumbiaOkanagan 3333 University Way Kelowna BC V1V 1VTCanada ZincNyx Energy Solutions Vancouver BC V6P 6T3 Canada

Industrial components made with a magnesium-aluminum alloy AZ31 are often used in diverse engineering applications where component weight, strength, and durability are critical. Similarly as other Mg alloys, however, the AZ31 is susceptible to corrosion in alkaline environments. In this work, corrosion of commercial grade AZ31 alloy plate was examined in potassium hydroxide （KOH） using immersion and potentiodynamic studies. The results suggest that the concentration of A1 and Mn in the alloy may govern the kinetics of micro-galvanic corrosion and the initiation of corrosion pits. Further, trace amounts of Ni in the AZ31 alloy were seen to enable formation of Ni（OH）2 surface layer, which may have further accelerated alloy corrosion due to its cracking and void coalescence. The effect of pH on the corrosion behavior of AZ31 was studied with reference to Pourbaix diagrams.

关键词： Magnesium alloy AZ31 KOH

A Semi-Random Multiple Decision-Tree Algorithm for Mining Data Streams

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Journal of Computer Science & Technology 2007年第5期22卷 711-724页

作者：胡学钢李培培吴信东吴共庆 School of Computer Science and Information Engineering Hefei University of Technology Hefei 230009China School of Computer Science and Information Engineering Hefei University of Technology Hefei 230009China Department of Computer ScienceUniversity of VermontBurlingtonVT 50405U.S.A.

Mining with streaming data is a hot topic in data mining. When performing classification on data streams, traditional classification algorithms based on decision trees, such as ID3 and C4.5, have a relatively poor efficiency in both time and space due to the characteristics of streaming data. There are some advantages in time and space when using random decision trees. An incremental algorithm for mining data streams, SRMTDS （Semi-Random Multiple decision Trees for Data Streams）, based on random decision trees is proposed in this paper. SRMTDS uses the inequality of Hoeffding bounds to choose the minimum number of split-examples, a heuristic method to compute the information gain for obtaining the split thresholds of numerical attributes, and a Naive Bayes classifier to estimate the class labels of tree leaves. Our extensive experimental study shows that SRMTDS has an improved performance in time, space, accuracy and the anti-noise capability in comparison with VFDTc, a state-of-the-art decision-tree algorithm for classifying data streams.

关键词： data streams Naive Bayes random decision trees

From landslide characterization to nature reserve management:The“Scialimata Grande di Torre Alfina”landslide Geosite(Central Apennines,Italy)

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Journal of Mountain Science 2023年第3期20卷 585-606页

作者： Gianluca TRONTI Francesca VERGARI Irene Maria BOLLATI Filippo BELISARIO Maurizio DELMONTE Manuela PELFINI Paola FREDI Earth Sciences Department"Ardito Desio" University La StataleMilan 20133(MI)Italy Monte Rufeno Nature Reserve Acquapendente 01021(VT)Italy Earth Sciences Department University La SapienzaRome 00185(RM)Italy

Italy is characterized by widespread geomorphological instability,among which landslides leave impressive marks on the ***,landslide bodies may represent key sites for thematic and educational itineraries,especially in protected areas,where their management becomes an important *** study focuses on the"Monte Rufeno Nature Reserve"(Central Apennines,Italy),where iconic landslides are ***,the"Scialimata Grande di Torre Alfina"landslide(SGTA)is listed in the regional Geosite *** work aims to propose a multiscale procedure for landslide analysis,in terms of both hazard sources but also educational and geoheritage enhancement opportunities in natural *** performing a Landslide Susceptibility conditional Analysis(LSA)for the reserve territory,attention was focused on the SGTA,to define properly its features and morphodynamics.A multi-disciplinary approach was adopted,by applying both remote sensing(UAV structure from motion,Photointerpretation)and field survey(geomorphological and GPS monitoring).From the LSA,based on drainage density,curvature,and slope triggering factors,the road and trail susceptibility maps were derived,as base tools for future risk assessments and trail paths management within the *** the SGTA scale,the monitoring showed a displacement of up to 23 m during the time interval between 2015 and *** landslide dynamics seem to be driven by alternating dry and extremely wet periods;moreover,leaks from the aqueduct in the detachment area and piping effects through clays may have also decreased the substrate *** SGTA complex influence on the Paglia River valley geometry was also hypothesized,underlining the action of landslide through different spatial scales(on-site and off-site)and on different environment features(sediment connectivity,hydrology).Finally,the SGTA appears highly representative of the geomorphic dynamics within the Nature Reserve(i.e.,scientific value)and it could be

关键词： Landslides Geoheritage Geosites Nature reserves management UAV structure from motion Landslides conditional analyses

Aboveground resilience to species loss but belowground resistance to nitrogen addition in a montane plant community

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Journal of Plant Ecology 2018年第3期11卷 351-363页

作者： Quentin D.Read Jeremiah A.Henning Aimée T.Classen Nathan J.Sanders Department of Ecology and Evolutionary Biology University of Tennessee569 Dabney HallKnoxvilleTN 37996USA Rocky Mountain Biological laboratory PO Box 615Crested ButteCO 81224USA Center for Macroecology Evolutionand ClimateNatural History Museum of DenmarkUniversity of CopenhagenUniversitetsparken 152100 CopenhagenDenmark Rubenstein School of Environment and Natural Resources University of VermontBurlingtonVT 05405USA

Aims Decades of empirical work have demonstrated how dominant plant species and nitrogen fertilization can influence the structure and function of plant *** recent studies have examined the interplay between these factors,but few such studies use an explicit trait-based *** this study,we use an explicit trait-based approach to identify potential mechanisms for community-level responses and to test ecological niche *** We experimentally manipulated plant communities(control,−dom-inant species,−random biomass)and nitrogen(N)inputs(control,+organic N,+inorganic N)in a fully factorial *** predicted that traits related to plants’ability to take up different forms of soil N would differ between dominant and subordinate species,resulting in interactive effects of dominant species loss and N fertilization on plant community structure and *** study took place in a montane meadow in the Rocky Mountains,Colorado,*** Findings After four years,the plant community in removal plots converged toward a species composition whose leaf and root functional traits resembled those of the previously removed dominant *** productivity generally increased with N addition:soil carbon efflux was~50%greater when either form of N was added,while inorganic N addition increased aboveground biomass pro-duction by~60%relative to *** increase in production was mediated by increased average height,leaf mass:area ratio and leaf dry matter content in plant communities to which we added inorganic *** to our predictions,there were no interactive effects of N fertilization and dominant species loss on plant com-munity structure or ecosystem *** plant community com-position in this study exhibited resistance to soil N addition and,given the functional convergence we observed,was resilient to spe-cies ***,our results indicate that the ability of species to compensate functionally for species loss confers

关键词： dominant species fertilization functional trait removal experiment resilience

Using Gamma Emissions to Identify Cycles in the Lower Cambrian Monkton Formation (NW Vermont): Implications for Identifying Sea Level Variation on the Iapetus Margin

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Open Journal of Geology 2019年第2期9卷 89-108页

作者： Henry Maguire Charlotte Mehrtens Jonathan Kim Edwin Romanowicz Department of Geology University of Vermont Burlington VT USA Vermont State Geological Survey Montpelier VT USA Department of Earth and Environmental Science SUNY Plattsburgh Plattsburgh NY USA

The Monkton Formation is described as a Lower Cambrian regressive sandstone unit containing shallowing-up cycles, called parasequences, which record tidal flat progradation. Spatial variation and limited outcrops of continuous stratigraphy have made it difficult to characterize how cycles change in architecture and thickness through the entirety of the Monkton Formation. This study seeks to identify stratigraphic trends in the parasequence architecture and thickness from the successful recognition of facies in the subsurface, information that will clarify how the sea level changes and impacts accommodation space. New geophysical data allow this research project to explore the stratigraphy of the Monkton at higher levels of resolution than previously achieved. Initial statistical study of gamma ray data from a well through the Monkton suggests that meter-scale parasequences are identifiable in geophysical logs. Using continuous gamma log data, this work identified clastic carbonate ratios from a 1034’ deep geothermal well drilled at Champlain College in Burlington, vt. Although cycles were identified in the gamma log, the spatial variation, complexity and variety of parasequence types within the Monkton made it difficult to correlate the sequences with specific environments or changes in sea level. To see if specific architectural elements of parasequences and lithologies could be characterized by gamma values, outcrops of the Monkton were surveyed containing both parasequences and lithologies that were useful paleobathymetric indicators. The survey determined gamma ray patterns and relative values of a common Monkton parasequence representing tidal flat progradation and a carbonate lithology indicating an abrupt sea level rise. Gamma data from a second well on the University of Vermont campus, along with accompanying borehole camera video, confirmed that the outcrop survey results could be useful in subsurface interpretations of the Monkton. Intervals representing t

关键词： Cambrian Sequence Stratigraphy Parasequence Vermont Sedimentary Sequence and Monkton

Advances in Inflammatory Bowel Disease

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Advances in Inflammatory Bowel Disease

Spectral Characteristics of CN Radical(B→X)and Its Application in Determination of Rotational and Vibrational Temperatures of Plasma

第十届全国儿童消化系统疾病学术会议

作者： Richard B.Colletti University of Vermont College of Medicine Burlington vt

Crohn’s disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases that can affect the entire gastrointestinal tract from mouth to anus in CD or the colon in UC. CD is mucosal and transmural disease that can progress to penetrating disease (fistula and abscess) and strictures;UC is mucosal disease. Both are associated with extra-intestinal manifestations, including primary sclerosing cholangitis, erythema

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Chinese Physics Letters 2011年第4期28卷 137-140页

作者： PENG Zhi-Min DING Yan-Jun ZHAI Xiao-Doug YANG Qian-Suo JIANG Zong-Lin State Key laboratory of Power Systems Department of Thermal EngineeringTsinghua UniversityBeijing 100084 laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190

The aim is to resolve the difficulties of measurement of temperature at several thousands of Celsius degrees for some unstable non-equilibrium gas *** on the molecular spectroscopy theory and inherent molecular structure characteristics of the CN radical,the dependence of the spectral profile on the rotational temperature(RT),vibrational temperature(vt)and optical apparatus function are numerically explored within some certain ***,by comparing the numerically calculated spectra with the experimental spectra of the CN radical,the corresponding RT and vt of the plasma induced by the interaction of the laser pulse from an oscillated Nd:YAG laser with the coal target are determined,*** addition,a short discussion on the thermodynamic state and the energy transfer process of the CN radical is also given.

关键词： Nd:YAG unstable apparatus