北京理加联合科技有限公司

LICA United Technology Limited

服务热线: 13910499761 010-51292601
企业邮箱
应用支持 Technical
News 应用支持
土壤水力参数,如田间持水量(FC)和永久萎蔫点(PWP),在灌溉管理、干旱风险评估和土地利用规划等方面发挥着重要作用。这些水力特性是动态的,随土壤类型、作物类型和生长季而变化。传统方法估算大尺度水力特性费时费力,而土壤传递函数(PTF)作为一种替代方法,已被用于使用易测量的土壤特性(如土壤粒级、有机碳和容重)来估计土壤水力特性。这些预测参数在很大程度上受各种内在土壤特性如土壤质地、结构、有机质、容重和孔隙度的影响。随着光谱技术的不断发展,因其快速、低成本和无损测量,许多研究者已经利用可见近红外(Vis-NIR)光谱预测了土壤特性,而使用光谱数据绘制印度土壤类型水力特性的研究非常有限。基于此,在本研究中,一组研究团队在印度卡纳塔克邦高原北部地区收集了558个土壤样本,在实验室中测量了其FC, PWP和土壤含水量,并利用ASD FieldSpec光谱仪测量土壤光谱反射率。通过支持向量机、随机森林和偏最小二乘回归三个模型预测FC和PWP。其中,2/3的数据集用于校准(368个样品),1/3的数据集用于验证(190个样品)。本研究目标为通过不同统计技术检验实验室Vis-NIR光谱数据估算水力参数的有用性。研究区域图【结果】卡纳塔克邦高原北部土壤光谱反射率分布(平均值和标准偏差)(N = 558)。FC和PWP预测模型的性能(50 次迭代)验证集FC和PWP预测值和观测值散点图(RF方法)(变性土-绿点,淋溶土-红点,弱育土-蓝点,新成土-黄点)。传统PTF方法预测验证集FC和PWP含水量的性能。【结论】验证结果表明,与PLSR模型相比,RF和SVM性能较好。与田间持水量(R2=0.66-0.69和RMSE=7.25-7.51%)相比,永久萎蔫点预测良好(R2=0.70-0.74,RMSE=5.44-5.74%)。在土纲中,Vis-NIR光谱(R2=0.34&0.42)对变性...
发布时间: 2022 - 11 - 18
浏览次数:2
Measurement of extremely 2H-enriched water samples by laser spectrometry: application to batch electrolytic concentration of environmental tritium samples国际原子能机构(International Atomic Energy Agency -- IAEA)研究人员应用LGR水同位素分析仪测量高2H富集水样(备注:该文章是IAEA的研究人员独立发表的文章,具有权威性、客观性和独立性,亦可广泛使用。)IAEA的研究人员发表了一篇应用LGR水同位素分析仪(912-0032)测量高2H富集水样的文章,文章有2个目的:(1)论证基于OA-ICOS技术的水同位素分析仪可以快速获得高准确性和高精度的自然丰度水样和氘富集水样(delta_2H ~ +57,000‰)的δ2HVSMOW-SLAP   数值;(2)随后论证基于激光技术2H富集方法测量水样的效能,以促进进行批处理3H电解富集的环境氚水实验室的生产力。文章中还简要说明了应用CRDS分析仪测量高2H富集水样的情况(CRDS水同位素分析仪可测量数值约为750‰的δ2HVSMOW-SLAP样品,但两个样品之间需要大于20次以上的注射才可去除显著...
发布时间: 2016 - 01 - 18
浏览次数:68
UNSW researchers have used a new water-tracing technology in the Sydney Basin for the first time to determine how groundwater moves in the different layers of rock below the surface.新南威尔士大学(UNSW)研究人员在悉尼盆地首次应用新的水源示踪技术监测地表下不同岩层下的地下水运动 http://newsroom.unsw.edu.au/news/science-tech/new-water-tracing-technology-help-protect-sydney-basin-groundwater
发布时间: 2016 - 01 - 15
浏览次数:29
LGR的二氧化碳同位素分析仪帮助中国科学院的科学家监测“新鲜有机物的质量对土壤有机物的启动和微生物底物利用率模式的影响” Quality of fresh organic matter affects priming of soil organic matter and substrate utilization patterns of microbesHui Wang1, 2 , Thomas W. Boutton3 , Wenhua Xu1 , Guoqing Hu1, 2 , Ping Jiang1 , Edith Bai1 AbstractChanges in biogeochemical cycles and the climate system due to human activities are expected to change the quantity and quality of plant litter inputs to soils. How changing quality of fresh organic matter (FOM) might influence the priming effect (PE) o...
发布时间: 2015 - 10 - 16
浏览次数:58
Rapid, Online Quantification of H2S in JP-8 Fuel Reformate Using Near-Infrared Cavity-Enhanced Laser Absorption Spectroscopy应用LGR激光痕量气体分析仪快速在线量化JP-8(特级航空材料)中的H2SFeng Dong†, Christian Junaedi‡, Subir Roychoudhury‡, and Manish Gupta*†† Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, California 94041, United States‡ Precision Combustion, Inc., 410 Sackett Point Road, North Haven, Connecticut 06473, United StatesAnal. Chem., 2011, 83 (11), pp 4132–4136DOI: 10.1021/ac200300tPublication Date (Web): May 3, 2011Copyright © 2011 American Chemical SocietyAbstractOn...
发布时间: 2015 - 10 - 10
浏览次数:61
Ecosystem carbon (CO2 and CH4) fluxes of a Populus dettoides plantationin subtropical China during and post clear-cutting Shenghua Gao a, Jiquan Chen b, Yuxi Tang c, Jing Xie d, Rui Zhang e, Jie Tang c, Xudong Zhang a,*a State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, Chinab Center for Global Change and Earth Observations (CGCEO) and Department of Geography, Michigan State University, East Lansing, MI 48823, USAc Hunan Academy of Forestry, Chang...
发布时间: 2015 - 09 - 15
浏览次数:42
HYPERSPECTRAL REMOTE SENSING FOR DETECTION OF RHIZOCTONIA CROWN AND ROOT ROT IN SUGARBEETGregory J. Reynolds1, Carol E. Windels2, Ian V. MacRae3, and Soizik Laguette4Graduate Student, Professor, Associate Professor, and Assistant Professor, respectively1University of Minnesota, Department of Plant Pathology, St. Paul2University of Minnesota, Department of Plant Pathology and Northwest Research & Outreach Center, Crookston3University of Minnesota, Department of Entomology and Northwest Research & Outreach Center, Crookston4University of North Dakota, Department of Earth System Science a...
发布时间: 2015 - 08 - 11
浏览次数:45
DETECTION OF SUGARCANE AFRICAN STALK BORER ELDANASACCHARINA WALKER (LEPIDOPTERA: PYRALIDAE) USINGHYPERSPECTRAL REMOTE SENSING (SPECTRORADIOMETRY)应用ASD地物光谱仪检测蛀虫ELDANA SACCHARINA(鳞翅目:螟蛾科)对非洲甘蔗茎部的危害程度MOKHELE TA1, AHMED F1 and CONLONG DE2,31School of Environmental Sciences, University of KwaZulu-Natal, Durban, 4041, South Africa2South African Sugarcane Research Institute, Private Bag X02, Mount Edgecombe 4300, South Africa3School of Biological and Conservation Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, South AfricaAbstractThe South African sugar industry i...
发布时间: 2015 - 08 - 06
浏览次数:61
LGR氧化亚氮同位素分析仪测量水中硝酸盐成功案例:Analytical Chemistry 文章:Combining Denitrifying Bacteria and Laser Spectroscopy for Isotopic Analyses (δ15N, δ18O) of Dissolved Nitrate通过反硝化细菌和激光同位素分析仪测定溶解硝酸盐中的δ15N和δ18ODavid X. Soto *†, Geoff Koehler †, and Keith A. Hobson †† Environment Canada, 11 Innovation Boulevard, Saskatoon, Saskatchewan, Canada, S7N 3H5AbstractWe present a novel approach for nitrogen (δ15N) and oxygen (δ18O) isotopic analysis of nitrate in water based on the isotopic analysis of N2O produced from the conversion of NO3– by cultured denitrifying bacteria and off-axis integrated cavity output ...
发布时间: 2015 - 07 - 21
浏览次数:57
Nature 发表文章:In-situ unsaturated zone stable water isotope (2H and 18O) measurements in semi-arid environments using tunable o-axis integrated cavity output spectroscopy科学家应用LGR液态水同位素分析仪在半干旱环境下原位测量不饱和带水中2H和18O同位素比值M. Gaj1,2,  M. Beyer1,  P. Koeniger1,  H. Wanke3,  J. Hamutoko3,  and T. Himmelsbach11 Federal Institue for Geosciences and Natural Resources (BGR), Stilleweg 2, Hannover, Germany2 Chair of Hydrology, Faculty of Environment and Natural Resources, University of Freiburg, Fahnenbergplatz, 79098 Freiburg, Germany3Universit...
发布时间: 2015 - 07 - 07
浏览次数:42
Inter- and intraindividual correlations of background abundances of 2H, 18O and 17O in human urine and implications for DLW measurements科学家应用LGR同位素分析仪测定人体尿液中的2H,18O和17O丰度间的相互作用对DLW测量方法的影响E S F Berman, E L Melanson, T Swibas, S P Snaith and J R SpeakmanBackground/Objectives:The method of choice for measuring total energy expenditure in free-living individuals is the doubly labeled water (DLW) method. This experiment examined the behavior of natural background isotope abundance fluctuations within and between individuals over time to assess possible methods of accounting for varia...
发布时间: 2015 - 07 - 01
浏览次数:33
148页次9/15首页上一页...  45678910111213...下一页尾页
Copyright ©2018-2023 北京理加联合科技有限公司
犀牛云提供企业云服务

北京理加联合科技有限公司

地址:北京市海淀区安宁庄东路18号光华创业园5号楼(生产研发)
          光华创业园科研楼四层
电话:13910499761 13910499762 010-51292601
传真:010-82899770-8014
邮箱:info@li-ca.com
邮编:100085

 

地址:深圳市宝安区创业二路玖悦雅轩商业裙楼3层瑞思BEEPLUS 3029室 手机:13910499772

 


 


  • 您的姓名:
  • *
  • 公司名称:
  • *
  • 地址:
  • *
  • 电话:
  • *
  • 传真:
  • *
  • 电子邮箱:
  • *
  • 邮政编码:
  • *
  • 留言主题:
  • *
  • 详细说明:
  • *
在线留言
关注我们
  • 官方微信
  • 官方手机端
友情链接:
X
1

QQ设置

3

SKYPE 设置

4

阿里旺旺设置

等待加载动态数据...

等待加载动态数据...

5

电话号码管理

  • 010-51292601
6

二维码管理

等待加载动态数据...

等待加载动态数据...

展开