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Neutron transmission imaging with a portable D-T neutron generator

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Radiation Detection Technology and Methods 2022年第2期6卷 234-243页

作者： Phillip Kerr Nerine Cherepy Jennifer Church Gary Guethlein jim Hall Colby McNamee Sean o'Neal Kyle Champley Andy Townsend Mayuki Sasagawa Anthony Hardy Saphon Hok Lawrence Livermore National Laboratory LivermoreCA 94550USA

Purpose A portable fast-neutron imaging system is being developed to provide complementary information to field X-ray *** include inspection of vehicles and infrastructure for corrosion,measurement of material levels in containers,and inspection of munitions and suspicious *** fast-neuron imaging generally provides lower imaging resolution compared to X-rays,fast-neutron interaction cross-sections have a weak dependence on material *** enables imaging of low-Z materials inside high-Z ***,we discuss the limitations and current improvements in fast-neuron *** Limitations in portable fast-neutron imaging systems include low D-T neutron generator output,low light pro-duction in ZnS(Cu)imaging scintillators,low resolution due to scintillator thickness and D-T spot size,and digital-panel darknoise that varies in time and position and that can be 100×larger than the neutron *** have made improvements in these areas through development of a segmented high light yield scintillator,panel noise mitigation techniques,and testing of new high-output,small spot size D-T neutron *** The segmented high light yield fast-neutron scintillator demonstrated 5×increase in light compared to ZnS(Cu).An additional 2×improvement in signal-to-noise was demonstrated with panel-noise mitigation *** MCNP calculations also show good agreement with neutron imaging results Conclusions We have demonstrated improvements in fast-neutron imaging through development of a segmented high light yield neutron scintillator,mitigation of digital panel noise,and preliminary testing with new high-output,small spot size D-T neutron *** have also demonstrated good results modeling fast-neutron images and scatter effects using MCNP.

关键词： Fast-neutron radiography Portable neutron imaging Neutron scintillators Monte Carlo simulation

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中文版word 97轻松入门

Wear modes in open porosity titanium matrix composites with TiC addition processed by spark plasma sintering

丛书名：当代计算机职业培训系列教程

1997年

作者：（美）（奥谢）jim o'Shea 杨富玉等译

175 p. : 图 ; 26cm 磁盘

ISBN: (纸本)7111057554

175 p. : 图 ; 26cm 磁盘

关键词：汉字处理软件系统基本知识

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Transactions of Nonferrous Metals Society of China 2019年第8期29卷 1653-1664页

作者： I. FARíAS L. oLMoS o. jiméNEZ M. FLoRES A. BRAEM J. VLEUGELS Departamento de Ingeniería de Proyectos Universidad de Guadalajara 45100 Zapopan Jalisco México Instituto de Investigaciones en Ciencias de la Tierra - INICIT Universidad Michoacana de San Nicolás de Hidalgo 58060 Morelia Michoacán México KU Leuven Department of Materials Engineering Kasteelpark Arenberg 44 B-3001 Heverlee Belgium

This work focused on the influence of TiC reinforcing particles on the tribological properties of titanium matrix composites(TMCs)with open porosity,processed by spark plasma sintering(SPS).Materials composed of an equimolar mixture of Ti and TiH2 with 0,3,10 and 30 vol.% of TiC were sintered at 850 ℃.Nanoindentation and wear tests were carried out to assess the nanohardness and the wear resistance in a tribometer with a reciprocating sliding ball-on-flat *** showed a nanohardness increment from 5 to 14 GPa with increasing TiC *** coefficient of friction(CoF)showed a minimum of 0.2 for 10% TiC grade,which also showed the lowest wear *** the low TiC content sample,adhesive wear with severe plastic deformation was ***,medium content TiC sample showed a mechanical mixed layer(MML),whereas high TiC content composite showed abrasive as the main wear *** conclusion,the wear mechanisms,CoFs and wear volume changed with TiC content.

关键词： porous titanium spark plasma sintering wear titanium matrix composites

Modeling susceptibility to deforestation of remaining ecosystems in North Central Mexico with logistic regression

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Journal of Forestry Research 2012年第3期23卷 345-354页

作者： L.Miranda-Aragón E.J.Trevi o-Garza J.jiménez-Pérez o.A.Aguirre-Calderón M.A.González-Tagle M.Pompa-García C.A.Aguirre-Salado Facultad de Ciencias Forestales Universidad Autónoma de NuevoLeón67700Linares NLMexico Facultad de Ciencias Forestales Universidad Juárez del Estado deDurango34120Durango DgoMexico Facultad de Ingeniería Universidad Autónoma de San Luis Potosí78290San Luis Potosi SLPMexico

Determining underlying factors that foster deforestation and delineating forest areas by levels of susceptibility are of the main challenges when defining policies for forest management and planning at regional scale. The susceptibility to deforestation of remaining forest ecosystems （shrubland, temperate forest and rainforest） was conducted in the state of San Luis Potosi, located in north central Mexico. Spatial analysis techniques were used to detect the deforested areas in the study area during 1993-2007. Logistic regression was used to relate explana- tory variables （such as social, investment, forest production, biophysical and proximity factors） with susceptibility to deforestation to construct predictive models with two focuses： general and by biogeographical zone In all models, deforestation has positive correlation with distance to rainfed agriculture, and negative correlation with slope, distance to roads and distance to towns. other variables were significant in some cases, but in others they had dual relationships, which varied in each biogeographi- cal zone. The results show that the remaining rainforest of Huasteca region is highly susceptible to deforestation. Both approaches show that more than 70% of the current rainforest area has high and very high levels of susceptibility to deforestation. The values represent a serious concern with global warming whether tree carbon is released to atmos- phere. However, after some considerations, encouraging forest environ- mental services appears to be the best alternative to achieve sustainableforest management.

关键词： GIS land use change proximity factors statistical modeling RoC curve regional forest planning

Sound art : beyond music, between categories

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2007年

作者： Alan Licht foreword by jim o'Rourke.

ISBN: (纸本)9780847829699

over the past century, an art form has emerged that draws from the worlds of visual art and music. Sound art’s roots can be found in the experimental work of Italian Futurism, Dada, and later the Fluxus group and the pioneering efforts of the American composer and artist John Cage. In the wake of this groundbreaking work, sound art began to mature into a movement, and artists explored the interact

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中文版Access 97轻松入门

Heterogeneous fenton oxidation of methylene blue with Fe-impregnated biochar catalyst

丛书名：当代计算机职业培训系列教程

1997年

作者：（美）（J.奥谢）jim o'Shea 启智翻译组译

本书内容包括创建表来存储数据,查找和编辑表记录,创建和使用查询来操作表中的数据等.

ISBN: (纸本)711105752X

本书内容包括创建表来存储数据,查找和编辑表记录,创建和使用查询来操作表中的数据等.

关键词：基本知识数据库管理系统,Access

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Biochar 2020年第2期2卷 164-175页

作者： Jong‑Hwan Park jim J.Wang Ki Hun Park Dong‑Cheol Seo Divison of Applied Life Science(BK21 Plus)and Institute of Agriculture and Life Science Gyeongsang National UniversityJinju 52828South Korea School of Plant Environmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLA 70803USA

Fe-impregnated biochar(Fe-BC)as high-efficiency heterogeneous Fenton catalyst was synthesized and evaluated in detail for its catalytic activity,stability and reusability under various *** optimal conditions for the Fenton oxidation of methylene blue(MB)as model dye were determined as 0.075 g/L H_(2)o_(2),0.5 g/L Fe-BC for 0.1 g/L MB,which resulted in optimum Dye:Fe_(cat):H_(2)o_(2) ratio of 1:5:0.75(on g/L basis)or[Dye]:[Fe_(total)]:[H_(2)o_(2)]molar ratio of 1:6.2:7.0 *** effective degradation of MB was identified over a wider pH range,and even after four consecutive runs Fe-BC maintained above 95%MB removal rate within 3 min of treatment with low Fe release,indicating strong stability and *** the optimum Dye:Fe_(cat):H_(2)o_(2)(g/L)condition at initial pH 4,the Fe-BC achieved 99.9%removal efficiency of MB within 3 min in heterogeneous Fenton reaction(HEFR)with much less H_(2)o_(2) concentration and low catalyst dosage,demonstrat-ing its efficiency and cost-effectiveness compared to other Fenton reaction *** removal velocity of MB showed two rate steps:a fast first stage followed by a slow stage with the rate in the order of H_(2)o_(2)/Fe-BC⋙H_(2)o_(2)/biochar>biochar>H_(2)o_(2).overall,the developed Fe-BC is more economical with strong stability and recyclability for use in HEFR for treating recalcitrant pollutants.

关键词： Fe-impregnated biochar catalyst Heterogeneous fenton reaction Impregnation and pyrolysis Removal velocity Methylene blue Sugarcane residue

An interactive tool for visualization and prediction of solar radiation and photovoltaic generation in Colombia

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Big Earth Data 2023年第3期7卷 904-929页

作者： Gabriel Narvaez Luis Felipe Giraldo Michael Bressan Camilo A.Guillen María A.Pabón Nicolás Díaz Manuel Felipe Porras Brayan Herney Medina Fernando jiménez Guillermo jiménez-Estévez Andres Pantoja Corinne Alonso Department of Electrical and Electronic Engineering Universidad de Los AndesBogotáColombia Laboratory for Analysis and Architecture of Systems ToulouseFrance Department of BiomedicalEngineering Universidad de Los AndesBogotáColombia Department of Systems Engineering Corporacion Universitaria del HuilaNeivaColombia Department of Electronic Engineering Universidad deNariñoPastoColombia

This paper presents the building process of an interactive instrument called the Colombian Solar Atlas able to easily visualize meteorological data but also assess the current and future potentials of solar photovoltaic generation throughout the whole territory of Colombia,South *** new tool is based on two different meteorological *** first one is done with historical data extracted from satellite imagery information,and the other one corresponds to data issues from regional-scale climate change projection *** satellite database was validated with different in-situ *** Colombian Solar Atlas uses basic and advanced photovoltaic generation models to estimate the generation of a custom solar *** this tool,a user selects a point on the map and can have directly pertinent information to search for an optimal location with a spatial resolution of 4 *** tool is the first open interactive online tool particularly adapted to study the photovoltaic power potential in Colombia,considering the country’s needs and native language.

关键词： Solar atlas PV power potential climate change Colombia data validation

Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in North Central Mexico

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Journal of Arid Land 2014年第1期6卷 80-96页

作者： Carlos A AGUIRRE-SALADo Eduardo J TREVIo-GARZA oscar A AGUIRRE-CALDERóN Javier jimNEZ-PREZ Marco A GoNZLEZ-TAGLE José R VALDZ-LAZALDE Guillermo SNCHEZ-DíAZ Reija HAAPANEN Alejandro I AGUIRRE-SALADo Liliana MIRANDA-ARAGóN Faculty of Forest Sciences Autonomous University of Nuevo Leon Faculty of Engineering Autonomous University of San Luis Potosi Forestry Program Postgraduate College Haapanen Forest Consulting Faculty of Agronomy and Veterinary Autonomous University of San Luis Potosí

As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest ***,national governments are interested in developing forest-monitoring strategies using geospatial *** statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical *** derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the *** of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out *** results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).our results are in agreement with those reported in the *** findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).

关键词： k-nearest neighbor Mahalanobis most similar neighbor MoDIS BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation