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太赫兹大气遥感技术

中国光学 2017年第5期10卷 656-665页

作者：胡伟东季金佳刘瑞婷王雯琦 leo p.ligthart 北京理工大学信息与电子学院北京100081 荷兰代尔夫特理工大学

由于其独特的大气敏感特性,太赫兹波在大气遥感领域起着越来越重要的作用。国际上太赫兹大气遥感技术发展方兴未艾。2004年,美国NASA发射AURA卫星,探测仪器中包括了具有两种极化的2.5 THz辐射计;2007年,欧空局ESA研制了Marschals外差式... 详细信息

由于其独特的大气敏感特性,太赫兹波在大气遥感领域起着越来越重要的作用。国际上太赫兹大气遥感技术发展方兴未艾。2004年,美国NASA发射AURA卫星,探测仪器中包括了具有两种极化的2.5 THz辐射计;2007年,欧空局ESA研制了Marschals外差式光谱仪,采用临边探测方式探测气体成分在亚毫米波段热辐射的高光谱。我国在轨气象卫星风云三号已经具备毫米波段辐射计,风云四号卫星是世界上首颗搭载太赫兹遥感仪的地球静止轨道气象卫星。针对我国大气遥感的现状,在概述国内外太赫兹遥感应用和技术的基础上,提出发展自主知识产权的大气遥感技术的思路;大力发展自主知识产权的太赫兹关键器件、太赫兹探测仪系统集成,研究太赫兹大气探测的新原理和反演新方法,整体提升我国在大气遥感领域的技术水平。

关键词：太赫兹大气遥感云粒子辐射计

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94GHz/220GHz双频喇叭天线设计

94GHz/220GHz双频喇叭天线设计

伴随“风云四号”闪耀星河的太赫兹大气遥感技术

2017年全国天线年会

作者：胡伟东王先南邓长江吕昕 leo p.ligthart 北京理工大学北京市毫米波与太赫兹技术重点实验室代尔夫特理工大学

本文设计了一种工作于94GHz和220GHz的双频喇叭天线。高频段采用双模过渡结构控制辐射方向图,低频段采用轴向波纹环控制辐射方向图,且波纹结构对高频段辐射特性不产生明显影响。馈电网络采用双频分路的正交模耦合器网络,实现了高端口隔... 详细信息

本文设计了一种工作于94GHz和220GHz的双频喇叭天线。高频段采用双模过渡结构控制辐射方向图,低频段采用轴向波纹环控制辐射方向图,且波纹结构对高频段辐射特性不产生明显影响。馈电网络采用双频分路的正交模耦合器网络,实现了高端口隔离度。天线在两个频段的辐射方向图均对称,且天线方向图副瓣电平小于-20d B,可以作为双频反射面天线的良好馈源。

关键词：双频极化正交太赫兹天线喇叭天线

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科技纵览 2020年第11期 60-64页

作者：胡伟东张铣宸陈实 leo p.ligthart 北京理工大学毫米波与太赫兹技术北京重点实验室首都师范大学太赫兹光电子学教育部重点实验室工业与信息化部无线电频率规划专家组北京理工大学荷兰代尔夫特理工大学

风云四号气象卫星作为洞悉风云变化的“慧眼”,搭载了许多先进的观测仪器,其中北京理工大学毫米波与太赫兹技术北京市重点实验室胡伟东研究团队参与研制的多通道毫米波太赫兹探测仪载荷助力风云四号闪耀星河,也将中国星载太赫兹大气探... 详细信息

风云四号气象卫星作为洞悉风云变化的“慧眼”,搭载了许多先进的观测仪器,其中北京理工大学毫米波与太赫兹技术北京市重点实验室胡伟东研究团队参与研制的多通道毫米波太赫兹探测仪载荷助力风云四号闪耀星河,也将中国星载太赫兹大气探测仪的研发和应用水平提升到了新的高度。

关键词：北京理工大学太赫兹探测重点实验室大气遥感观测仪器风云变化太赫兹技术风云四号

Covid-19 vaccination in pregnancy and placental pathology

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Asian pacific Journal of Reproduction 2024年第2期13卷 76-79页

作者： leo Simanjuntak Department of Obstetrics and Gynecology Faculty of MedicineUniversitas HKBP NommensenMedanIndonesia

Objective:To describe and determine the association between Covid-19 vaccination in pregnancy and placental ***:Conducted in a tertiary hospital in Medan,Indonesia,from April 30th 2022 to June 30th 2022,this single-center cross-sectional study involved Covid-19 vaccinated and unvaccinated women with singleton full-term pregnancies delivering live fetuses via cesarean *** characteristics,placental pathologies,and the placental index were documented at *** association between Covid-19 vaccination status and placental pathology was ***:The study enrolled 200 pregnant women,including 110 vaccinated women and 90 unvaccinated *** significant differences were observed in birthweight(p=0.48),placental index(p=0.48),and placental pathology findings[intervillous bleeding(p=0.20),increased syncytial knots(p=0.83),chorangiosis(p=0.13),villous stromal edema(p=0.13),vascular dilation and congestion(p=0.13),and vascular wall thrombus(p=0.71)]between the vaccinated and unvaccinated ***:This study revealed no statistically significant association between Covid-19 vaccination and placental *** findings support the safety of Covid-19 vaccination during pregnancy,in regards to changes of the placental pathology.

关键词： Covid-19 Vaccination pregnancy Women placenta

Impact of indoor heat load and natural ventilation on thermal comfort of radiant cooling system:An experimental study

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Energy and Built Environment 2023年第5期4卷 543-556页

作者： K Dharmasastha D.G.leo Samuel S.M.Shiva Nagendr M.p.Maiya Department of Mechanical Engineering Indian Institute of Technology MadrasChennaiTamil Nadu 600036India Barghest Building performance pte.Ltd. 118535Singapore Department of Civil Engineering Indian Institute of Technology MadrasRefrigeration and Air ConditioningChennai 600036India Department of Building Enivironment and Energy Engineering The Hong Kong Polytechnic UniversityHong Kong

Construction and operation of buildings are responsible for about 20%of the global energy *** embodied energy of conventional buildings is high due to the utilization of energy-intensive construction mate-rials and traditional construction *** operational energy is attributed to the usage of power-consuming conventional air-conditioning ***,moving to an energy-efficient cooling technology and eco-friendly building material can lead to significant energy savings and CO 2 emission *** the present study,an energy-efficient thermally activated building system(TABS)is integrated with glass fiber rein-forced gypsum(GFRG),an eco-friendly building *** proposed hybrid system is termed the thermally activated glass fiber reinforced gypsum(TAGFRG)*** system is not only energy-efficient and eco-friendly but also provides better thermal *** experimental room with a TAGFRG roof is constructed on the premises of the Indian Institute of Technology Madras(IITM),Chennai,located in a tropical wet and dry climate *** influence of indoor sensible heat load and the impact of natural ventilation on the thermal comfort of the TAGFRG system are *** increase in internal heat load from 400 to 700 W deteriorates the thermal comfort of the indoor *** is evident from the increases in operative temperatures from 29.8 to 31.5℃ and the predicted percentage of dissatisfaction from 44.5%to 80.9%.Natural ventilation increases the diurnal fluctuation of indoor air temperature by 1.6 and 1.9℃ for with and without cooling cases,*** reduces the maximum indoor CO 2 concentration from 912 to 393 ppm.

关键词： Thermally activated building system Air-conditioning Natural ventilation Thermal comfort Indoor air quality

The “mitochondrial stress responses”: the “Dr. Jekyll and Mr. Hyde” of neuronal disorders

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Neural Regeneration Research 2022年第12期17卷 2563-2575页

作者： Simone patergnani Giampaolo Morciano Marianna Carinci Sara leo paolo pinton Alessandro Rimessi Department of Medical Sciences Section of Experimental MedicineLaboratory for Technologies of Advanced TherapiesUniversity of FerraraFerraraItaly Center of Research for Innovative Therapies in Cystic Fibrosis University of FerraraFerraraItaly

Neuronal disorders are associated with a profound loss of mitochondrial functions caused by various stress conditions,such as oxidative and metabolic stress,protein folding or import defects,and mitochondrial DNA *** engage in different coordinated responses to safeguard mitochondrial *** this review,we will explore the contribution of mitochondrial stress responses that are activated by the organelle to perceive these dangerous conditions,keep them under control and rescue the physiological condition of nervous *** the sections to come,particular attention will be dedicated to analyzing how compensatory mitochondrial hyperfusion,mitophagy,mitochondrial unfolding protein response,and apoptosis impact human neuronal ***,we will discuss the relevance of the new concept:the“mito-inflammation”,a mitochondria-mediated inflammatory response that is recently found to cover a relevant role in the pathogenesis of diverse inflammatory-related diseases,including neuronal disorders.

关键词： Alzheimer’s disease apoptosis mitochondrial dynamics mito-inflammation mitophagy multiple sclerosis neurodegeneration parkinson’s disease UpRmt

Absence of complementary sex determination in two Leptopilina species(Figitidae,Hymenoptera)and a reconsideration of its incompatibility with endosymbiont-induced thelytoky

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Insect Science 2022年第3期29卷 900-914页

作者： Fangying Chen Martijn Schenkel Elzemiek Geuverink Louis van de Zande leo W.Beukeboom Groningen Institute for Evolutionary Life Sciences University of GroningenP.O.Box 11103 Groningen9700 CCthe Netherlands

Complementary sex determination(CSD)is a widespread sex determination mechanism in haplodiploid *** CSD,sex is determined by the allelic state of one or multiple CSD *** at one or more loci leads to female development,whereas hemizygosity of haploid eggs and homozygosity of diploid eggs results in male ***(arrhenotokous)reproduction normally yields haploid male and diploid female *** asexual reproduction(thelytoky),diploidized unfertilized eggs develop into *** is often induced by bacterial endosymbionts that achieve egg diploidization by gamete *** gamete duplication leads to complete homozygosity,endosymbiont-induced thelytokous reproduction is presumed to be incompatible with CSD,which relies on heterozygosity for female ***,we excluded CSD in four Asobara(Braconidae)species and proposed a two-step mechanism for Wolbachia-induced thelytoky in Asobara ***,we conclusively reject CSD in two cynipid wasp species,Leptopilina heterotoma and Leptopilina *** further show that thelytoky in *** depends on Wolbachia titer but that diploidization and feminization steps cannot be separated,unlike in *** discuss what these results reveal about the sex determination mechanism of *** and the presumed incompatibility between CSD and endosymbiont-induced thelytoky in the Hymenoptera.

关键词： arrhenotoky haplodiploidy inbreeding sex determination thelytoky Wolbachia bacteria

Supplementing oat hulls to the diet of suckling piglets altered their intestinal tract and colonic microbiota development

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Animal Nutrition 2023年第1期12卷 284-296页

作者： Hubèrt M.J.van Hees Koen Chiers leo A.den Hartog Theo A.T.G.van Kempen Dominiek Maes Sam Millet Geert p.J.Janssens Department of Veterinary and Biosciences Ghent UniversityMerelbekeBelgium Trouw Nutrition Research and Development Amersfoortthe Netherlands Department of pathology Ghent UniversityMerelbekeBelgium Animal Nutrition Wageningen University and ResearchWageningenthe Netherlands Department of Animal Science North Carolina State UniversityRaleighNCUSA Department of Reproduction Obstetrics and Herd HealthGhent UniversityMerelbekeBelgium ILVO(Flanders Research Institute for Agriculture Fisheries and Food)MelleBelgium

Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling *** hulls(OH)were selected as a model feedstuff,rich in cellulose,lignin,and insoluble dietary *** experimental supplemental diets were formulated:a finely ground,low fibre and nutrient dense diet served as control(CON).For the 2 high fibre diets,15%heat-treated starch in CON was exchanged with OH,either finely(OH-f)or coarsely ground(OH-c).Litters of 10 primi-and multiparous sows(mean litter size 14.6±0.84)were *** a litter,experimental diets were allotted to triplets of 4 *** approximately 12 d of age,piglets’individual feed intakes were recorded 2 times per day when separated from their dam for 70 *** could suckle with their dam for the remainder of the *** d 24 and 25,from the total pool of 120 piglets,seven healthy well-eating piglets per treatment were selected for post-mortem evaluation,resulting in 14 replicates per *** of OH-c and OH-f did not impede clinical health and production performance of *** full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate(p=0.083).Supplementing OH significantly increased ileal villus height and caecal dry matter concentration(pproteobacteria count and proportion(ppecifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and ***,OH-c reduced colonic crypt depth when compared to OH-f(p=0.018).In conclusion,supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial *** effects were largely independent from the particle size of the OH.

关键词： Oat hull Insoluble fibre Gastrointestinal development Suckling piglet

Superhydrophobic pVDF/TiO_2-SiO_2 Membrane with Hierarchical Roughness in Membrane Distillation for Water Recovery from phenolic Rich Solution Containing Surfactant

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Chinese Journal of polymer Science 2019年第6期37卷 609-616页

作者： N.Hamzah C.p.leo B.S.Ooi School of Chemical Engineering Engineering Campus Universiti Sains Malaysia

Superhydrophobic poly(vinylidene fluoride)(pVDF) membrane incorporated with nanoparticles was applied in membrane distillation to recover water from phenolic rich solution containing surfactant. The membranes coated on woven support were fabricated using phase inversion with dual bath coagulation and post-modified using silane. The membranes incorporated with TiO_2, SiO_2, or a mixture of TiO_2-SiO_2 nanoparticles achieved the water contact angle higher than 160°. The addition of TiO_2-SiO_2 mixture into pVDF matrix further enhanced the hierarchical roughness of membrane. Hence, pVDF/TiO_2-SiO_2 membrane achieved the highest permeation flux and rejected 99.9% of gallic acid in the feed(100 g/L). pVDF/TiO_2-SiO_2 membrane also maintained a relative flux(J/J0) higher than0.9 after 8 h of operation. Even with the presence of surfactant in phenolic rich solution, pVDF/TiO_2-SiO_2 membrane was able to exhibit relative flux above 0.8. The significant changes on the hydrophobicity and chemical properties of pVDF/TiO_2-SiO_2 membrane due to fouling were not observed after 50 h of static adsorption test.

关键词： Superhydrophobic pVDF Nano particles Roughness Membrane distillation