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从BRDF到BPDF:遥感反演基础模型的演进初探

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中国科学:信息科学 2024年第8期54卷 2001-2020页

作者：尚可晏磊张飞舟褚君浩杨彬刘思远 kevin TANSEY 贾秀萍 Oleg DUBOVIK 张子晗李飞北京大学地球与空间科学学院遥感与地理信息系统研究所北京大学空间信息集成与3S工程应用北京市重点实验室中国科学院上海技术物理研究所红外物理国家重点实验室湖南大学电气与信息工程学院中国兵器工业导航与控制技术研究所 School of Geography Geology and the Environment University of Leicester School of engineering and Technology The University of New South Wales Laboratoire d'Optique Atmosphérique CNRS/Université Lille

光的本质是横波电磁波矢量,以双向反射分布函数BRDF (bidirectional reflectance distribution function)为基础模型的标量遥感体系只利用植被反射光的整体强度信息,无法进一步区分反射辐射蕴含的叶表、叶内和冠层结构信息;在标量遥感... 详细信息

光的本质是横波电磁波矢量,以双向反射分布函数BRDF (bidirectional reflectance distribution function)为基础模型的标量遥感体系只利用植被反射光的整体强度信息,无法进一步区分反射辐射蕴含的叶表、叶内和冠层结构信息;在标量遥感基础上考虑垂直于电磁波传播方向的二维偏振矢量特性(强度+方向)就能深化为矢量遥感体系,从而有望精确刻画反射光中蕴含的多种信息,提升植被参数反演精度.刻画偏振反射空间分布的双向偏振分布函数BPDF目前存在精度低、泛化性差等问题,因此进一步探索矢量遥感基础理论,构建通用性强的植被矢量遥感基础模型具有迫切的现实需求.本文旨在利用光子与植被元素的相互作用构建通用性较强的植被BPDF物理模型.首先基于光子–植被元素相互作用的光谱不变原理,提出基于方向逃逸概率的植被BPDF物理模型基础形式,并基于植被单次反射的辐射传输理论推导模型解析表达;随后通过考虑叶片散射随干物质含量的变化,提出光谱不变原理优化表达并推导模型通用表达式;最后分别利用三维矢量辐射传输模型和多尺度实测数据实现模型的正演直接验证和间接验证.结果表明,本文构建的BPDF物理模型的解析表达和通用表达在不同植被场景下,对偏振反射率的正演均方根误差可达0.001以内,与矢量辐射传输模型正演结果在半球空间内具有很强一致性,在多尺度实测数据也简洁验证了模型关系的稳定性,模型R2普遍高于0.9.相比于现存植被偏振反射模型,本文构建的模型兼具物理机理、简洁形式、可接受的参数化方案、较高精度和较强泛化能力,对浓密植被具备通用性,为在BRDF一维标量遥感的基础上进一步考虑BPDF二维偏振特性从而形成矢量遥感体系这一转变过程提供了理论基础和探索性方案.

关键词：植被 BPDF 矢量遥感物理模型偏振

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Interfacial engineering through lead binding using crown ethers in perovskite solar cells

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Journal of Energy Chemistry 2024年第5期92卷 263-270页

作者： Sun-Ju Kim YeonJu Kim Ramesh Kumar Chitumalla Gayoung ham Thanh-Danh Nguyen Joonkyung Jang hyojung Cha Jovana Milić Jun-ho Yum kevin Sivula Ji-Youn Seo Department of Nano Fusion Technology Pusan National UniversityBusan 46241Republic of Korea Laboratory for Molecular engineering of Optoelectronic Nanomaterials Institute of Chemical Sciences and EngineeringÉcole Polytechnique Fédérale de Lausanne(EPFL)1015 LausanneSwitzerland Department of Energy Convergence and Climate Change Kyungpook National UniversityDaegu 41566Republic of Korea Department of hydrogen and Renewable Energy Kyungpook National UniversityDaegu 41566Republic of Korea Adolphe Merkle Institute University of FribourgCH-1700 FribourgSwitzerland

In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative *** study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial *** ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material *** ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation *** crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial *** devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial *** techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative ***,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative *** research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.

关键词： Perovskite solar cells Interfacial passivation Crown ether materials Stability

Poisoning effect of polyvinyl chloride on the catalytic pyrolysis of mixed plastics over zeolites

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Science China Chemistry 2024年第7期67卷 2265-2273页

作者： Jiangchun Yuan Wenjie Wang Weixiao Sun Zhirong Yang Yueqiang Cao Wenyao Chen Xiaohu Ge Gang Qian Xiang Feng Xuezhi Duan Xinggui Zhou kevin M.Van Geem Jing Zhang State Key Laboratory of Chemical engineering East China University of Science and TechnologyShanghai 200237China School of Chemical engineering Zhengzhou UniversityZhengzhou 450001China Laboratory for Chemical Technology(LCT) Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering&ArchitectureGhent UniversityZwijnaarde B-9052Belgium State Key Lab of heavy Oil Processing China University of PetroleumQingdao 266580China

Nowadays,the chemical recycling is applied for only 1%of total waste plastics,largely due to contaminants in plastic waste and difficulty in product *** the major contaminant,polyvinyl chloride(PVC)often forms corrosive hydrogen chloride(hCl)during the chemical recycling,which may cause severe catalyst deactivation and equipment ***,the investigation on catalytic pyrolysis(the major route for plastics chemical recycling)of the PVC containing mixed plastics has been rarely ***,catalytic co-pyrolysis of PVC and polyethylene(PE)was studied over an aromatization catalyst,Pt/ZSM-5,since the basic building block aromatics are desired products from plastics chemical *** poisoning effect of PVC vapor on the catalyst stability was explored by collective efforts of thorough product analysis and catalyst *** was found that the hCl evolving from PVC has an autocatalytic effect that promotes the scission of dehydrochlorinated PVC,resulting in the high yield of benzene and acetylene from *** the other hand,the presence of PVC suppressed the aromatics formation from PE,largely due to the poisoning effect of PVC-derived hCl on the Pt/*** deactivation is irreversible as evidenced by the decreased zeolite crystallinity and the loss of strong acid sites that are key to the aromatization,possibly due to the removal of framework Al upon the interaction with *** modification with octadecylphosphonic acid only slightly alleviated the PVC poisoning *** insights on the PVC poisoning of zeolite catalysts provided in this work may guide the process design of chemical recycling of PVC containing waste plastics.

关键词： polyvinyl chloride polyethylene zeolite aromatics deactivation

Tensorial tomographic Fourier ptychography with applications to muscle tissue imaging

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Cognitive function among military veterans with STEM occupations

Advanced Photonics 2024年第2期6卷 50-60页

作者： Shiqi Xu Xi Yang Paul Ritter Xiang Dai Kyung Chul Lee Lucas Kreiss kevin C.Zhou Kanghyun Kim Amey Chaware Jadee Neff Carolyn Glass Seung Ah Lee Oliver Friedrich Roarke horstmeyer Duke University DurhamNorth CarolinaUnited States Friedrich-Alexander University ErlangenGermany UC San Diego La JollaCaliforniaUnited States Yonsei University SeoulRepublic of Korea UC Berkeley BerkeleyCaliforniaUnited States Duke University Medical Center DurhamNorth CarolinaUnited States

We report tensorial tomographic Fourier ptychography(T^(2)oFu),a nonscanning label-free tomographic microscopy method for simultaneous imaging of quantitative phase and anisotropic specimen information in *** upon Fourier ptychography,a quantitative phase imaging technique,T^(2)oFu additionally highlights the vectorial nature of *** imaging setup consists of a standard microscope equipped with an LED matrix,a polarization generator,and a polarization-sensitive *** tensors of anisotropic samples are computationally recovered from polarized intensity measurements across three *** demonstrate T^(2)oFu’s efficiency through volumetric reconstructions of refractive index,birefringence,and orientation for various validation samples,as well as tissue samples from muscle fibers and diseased heart *** reconstructions of healthy muscle fibers reveal their 3D fine-filament structures with consistent ***,we demonstrate reconstructions of a heart tissue sample that carries important polarization information for detecting cardiac amyloidosis.

关键词： computational imaging three-dimensional imaging phase retrieval microscopy polarization-sensitive imaging labelfree imaging

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Military Medical Research 2024年第2期11卷 308-310页

作者： Justin T.McDaniel kevin N.hascup Erin R.hascup Ugochukwu G.Ezigbo Amanda M.Weidhuner harvey henson David L.Albright Dale and Deborah Smith Center for Alzheimer's Research and trEatment(CARE) Southern Illinois University School of MedicineSpringfieldIL 62794USA STEM Education Research Center Southern Illinois UniversityCarbondaleIL 62901USA Department of Political Science The University of AlabamaTuscaloosaAL 35487USA

Dear Editor,There is limited research on the relationship between science,technology,engineering,and mathematics(STEM)occupational history and cognitive function in later life,especially among military veterans,who may be at greater risk for later-life cognitive *** study examines a nationally representative sample of military veterans to address this gap in knowledge.

关键词： Alzheimer's disease Veterans Science technology engineering and mathematics(STEM) Animal fluency test Dementia

Direct anterior compared to posterior approach for hip hemiarthroplasty following femoral neck fractures

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World Journal of Orthopedics 2024年第6期15卷 605-607页

作者： kevin A Wu Alexandra N Krez Albert T Anastasio Department of Orthopaedic Surgery Duke University HospitalDurhamNC 27710United States Department of Orthopaedic Surgery Duke University School of MedicineDurhamNC 27710United States

The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully ***,a severe complication associated with increased mortality and often requiring additional surgery,may occur less frequently with the direct anterior approach compared to the posterior *** consideration of patient demographics is essential when planning the surgical *** research in this area should focus on robust randomized controlled trials involving elderly patients recovering from femoral neck fractures.

关键词： Direct anterior approach Posterior approach hemiarthroplasty Femoral neck fractures Arthroplasty Dislocation Surgical technique

Epidemiologic investigation of pediatric distal humerus fractures: An American insurance claims database study

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World Journal of Orthopedics 2024年第1期15卷 52-60页

作者： Kyle Jay Klahs Jake E Dertinger Grant T Mello kevin Thapa Alexis B Sandler E'Stephan J Jesus Garcia Nata Parnes Department of Orthopaedic Surgery Texas Tech University Health Sciences-El PasoEl PasoTX 79905United States Medical School California Health Sciences University College of Osteopathic MedicineClovisCA 93611United States Undergraduate School Binghampton UniversityVestalNY 13902United States Department of Orthopaedic Surgery William Beaumont Army Medical CenterFort BlissTX 79918United States Department of Orthopaedic Surgery Carthage Area HospitalCarthageNY 13619United States

BACKGROUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(ME)*** To evaluate the epidemiology of pediatric distal humerus fractures(SC,LC,and ME)from an American insurance claims *** A retrospective review was performed on patients 17 years and younger with the ICD 9 and 10 codes for SC,LC and ME fractures based on the IBM Truven MarketScan®Commercial and IBM Truven MarketScan Medicare Supplemental *** from 2015 to 2020 were queried for treatments,patient age,sex,length of hospitalization,and *** A total of 1133 SC,154 LC,and 124 ME fractures were *** fractures had the highest percentage of operation at 83%,followed by LC(78%)and ME fractures(41%).Male patients were,on average,older than female patients for both SC and ME *** In the insurance claims databases used,SC fractures were the most reported,followed by LC fractures,and finally ME *** was identified to be a factor for how a pediatric distal humerus fractures,with patients with SC and LC fractures being younger than those with ME *** peak age per injury per sex was similar to reported historic central tendencies,despite reported trends for younger physiologic development.

关键词： Supracondylar humerus fracture Lateral condyle fracture Medial epicondyle fracture Pediatric elbow Truven Epidemiology

Psychiatric comorbidities in children with conduct disorder:a descriptive analysis of real-world data

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General Psychiatry 2024年第2期37卷 301-305页

作者： Tashalee R Brown Anita S Kablinger Robert Trestman Eraka Bath Cynthia Rogers Binx Yezhe Lin kevin Young Xu University of California Los Angeles David Geffen School of Medicine Los AngelesCaliforniaUSA Department of Psychiatry and Behavioral Medicine Virginia Tech Carilion School of MedicineRoanokeVirginiaUSA Washington University in St Louis School of Medicine St LouisMissouriUSA Clinical Research Center for Mental Disorders Chinese-German Institute of Mental HealthShanghai Pudong New Area Mental Health CenterSchool of MedicineTongji UniversityShanghaiChina Department of Psychosomatic Medicine Shanghai East HospitalTongji University School of MedicineShanghaiChina Department of Psychiatry Washington University School of Medicine in Saint LouisSt LouisMissouriUSA

To the editor:Two recent advisories from the US surgeon general have underscored the unprecedented public health crisis in youth mental health and emphasised the need for“timely data collection and research to identify and respond to youth mental health needs more rapidly”.1 Increased rates of suicidal behaviour,depression and anxiety symptoms and substance use.

关键词： morbid Psychiat editor

Asbestos Exposure during Gasket Removal from Aircraft engine

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Occupational Diseases and Environmental Medicine 2024年第2期12卷 59-67页

作者： Charles L. Blake kevin M. Guth Raymond D. harbison Apex Companies Marietta USA Center for Environmental and Occupational Risk Analysis and Management College of Public Health University of South Florida Tampa USA

We have previously evaluated asbestos exposure associated with various maintenance procedures on light aircraft. The purpose of this study was to evaluate asbestos exposure during engine maintenance on light aircraft. This test was designed to evaluate the potential for asbestos exposure to mechanics and others who remove asbestos-containing engine gaskets from reciprocating style aircraft engines. Utilized in this test was an air cooled, horizontally opposed, aviation gasoline burning engine, assembled during 1986 and operated intermittently up into 2015, having accumulated 1680 hours run time. Nearly 75% of the asbestos-containing gaskets installed during 1986 were still in place at the time of testing. Chrysotile asbestos contents of such gaskets ranged from 55% to 60% by area, for those of sheet style and 5% by area, for the spiral wound metal/asbestos style. Despite the levels of effort required to effect gasket removals, the professional aircraft mechanic was not exposed to airborne asbestos fibers at the lower limits of sampling and analytical detection achieved;all of which were substantially less than the current Occupational Safety and health Administration Permissible Exposure Limits for asbestos. The results of this testing indicate an absence of gasket related asbestos exposure risk to mechanics who work with light aircraft engines, including those having asbestos-containing gaskets. These results are consistent with the findings of Mlyarek and Van Orden who studied the asbestos exposure risk occasioned during overhaul of larger radial style reciprocating aircraft engines [1].

关键词： Asbestos Exposure Gaskets Aircraft engine Friction Materials