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Atmospheric Corrections Using MODTRAN for TOA and Surface BRDF Characteristics from High Resolution Spectroradiometric/ Angular Measurements from a Helicopter Platform

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Advances in Atmospheric Sciences 2001年第5期18卷 984-1004页

作者： Yaping Zhou, Ken C. Rutledge Analytical Service & Material, Inc, Hampton, va, USA Thomas P. Charlock Atmospheric Sciences Division, NASA Langley Research Center Hampton, va, USA Norman G. Loeb, Seiji Kato Hampton University, Hampton, va, USA Analytical Service & Material Inc Hampton USA Atmospheric Sciences Division NASA Langley Research Center Hampton USA Hampton University Hampton USA

High-resolution spectral radiance measurements were taken by a spectral radiometer on board a heli- copter over the US Oklahoma Southern Great Plain near the Atmospheric Radiation Measurements (ARM) site during August 1998. The radiometer has a spectral range from 350 nm to 2500 nm at 1 nm resolution The measurements covered several grass and cropland scene types at multiple solar zenith angles. Detailed atmospheric corrections using the Moderate Resolution Transmittance (MODTRAN) radiation model and in-situ sounding and aerosol measurements have been applied to the helicopter measurements in order to re- trieve the surface and top of atmosphere (TOA) Bidirectional Reflectance Distribution Function (BRDF) characteristics. The atmospheric corrections are most significant in the visible wavelengths and in the strong water vapor absorption wavelengths in the near infrared region Adjusting the BRDF to TOA requires a larger correction in the visible channels since Rayleigh scattenng contributes significantly to the TOA reflectance. The opposite corrections to the visible and near infrarred wavelengths can alter the radiance dif- ference and ratio that many remote sensing techniques are based on, such as the normalixed difference vege- tation index (NDVI). The data show that surface BRDFs and spectral albedos are highly sensitive to the veg- etation type and soldr zenith angle while BRDF at TOA depends more on atmospheric conditions and the vi ewing geometry. Comparison with the Clouds and the Earth's Radiant Energy System (CERES) derived clear sky Angular Distribution Model (ADM) for crop and grass scene type shows a standard deviation of 0.08 in broadband anisotropic function at 25°solar zenith angle and 0.15 at 50° solar zenith angle, respectively.

关键词： BRDF Radiative transfer Atmospheric correction

Petrophysical Characteristics of Silurian Mudstones from Central Taurides in Southern Turkey

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Journal of Earth Science 2021年第4期32卷 778-798页

作者： Zeynep Döner Qinhong Hu Mustafa Kumral Md Golam Kibria Hongguo Qiao Mengdi Sun Department of Geological Engineering Faculty of MinesIstanbul Technical UniversityIstanbul 34469Turkey Department of Earth and Environmental Sciences The University of Texas at ArlingtonArlington TX 76019USA Shandong Provincial Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China

This study used a range of integrated and complementary experiments to examine porestructure,fluid-shale wetting characteristics,sample size-dependent porosity towards different fluids,and imbibition behavior,as well as the relationships between these properties and the mineralogy of Silurian mudstones in the Central Taurides of Turkey.Working with different sample-sizes,the experiments consisted of helium pycnometry,low-pressure nitrogen physisorption isotherm,mercury intrusion porosimetry,fluid immersion porosimetry,liquid displacement,fluid droplet wettability and contact angle measurements,and spontaneous imbibition of fluids;four fluids with different hydrophilicity were used to assess the characteristics of fluid-shale interaction and its influence on porestructure.Results show that studied mudstones can be grouped into three rock types:siliceous,carbonate-dominated,and mixed mudstones.Siliceous and mixed mudstones have higher porosities,pore-throat diameters,surface areas and tortuosities than the carbonate-dominated mudstones,regardless of sample sizes and fluids used.With low permeabilities and medium pore-throat sizes for the siliceous and mixed mudstones,the wettability and imbibition results show that these mudstones are both oil-wet and moderately-to-high water-wet.In contrast,the carbonate-dominated mudstones exhibit oil-wet characteristics.These results indicate that studied siliceous and mixed mudstones in the Central Taurides seem to have appropriate petrophysical properties in the context of reservoir quality.

关键词： Silurian mudstones Central Taurides of Turkey petrophysical properties pore structure connectivity fractal dimension

Bericht ber die Reise nach China

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德语人文研究 2001年第3期 49-52页

作者： Bianca Hauβner

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核子电磁形状因子振荡行为的新视角（英文）

Science Bulletin 2023年第22期 2729-2733+2669页

作者：杨勤鹤郭棣戴凌云 Johann Haidenbauer 康现伟 Ulf-G. Mei?ner School of Physics and Electronics Hunan University Hunan Provincial Key Laboratory of High-Energy Scale Physics and Applications Hunan University Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron Physics Forschungszentrum Jülich Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and Technology Beijing Normal University Institute of Radiation Technology Beijing Academy of Science and Technology Helmholtz Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universit?t Bonn Tbilisi State University

本文研究了质子和中子的类时电磁形状因子.作者基于手征有效场论,通过求解李普曼-施温格方程得到了核子-反核子对散射振幅.以此为输入,利用扭曲波恩近似方法描述了核子末态相互作用,计算了正负电子湮灭到正反核子对的过程.通过拟合相移...

本文研究了质子和中子的类时电磁形状因子.作者基于手征有效场论,通过求解李普曼-施温格方程得到了核子-反核子对散射振幅.以此为输入,利用扭曲波恩近似方法描述了核子末态相互作用,计算了正负电子湮灭到正反核子对的过程.通过拟合相移、截面以及微分截面等实验数据,定下了有效场论的未知耦合常数.进一步研究发现,可以利用两个分数振荡振子来描述核子电磁类时形状因子的振荡行为:一个表现为过阻尼振荡,在阈值附近占主导地位;另一个类似于欠阻尼振荡,在高能区起到重要作用.这种振荡行为对理解硬光子诱导的核子内部极化电荷的分布起着至关重要的作用.

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Pressure Slip Casting of Graded Coarse Grained Oxide Ceramics for Refractory Applications

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China's Refractories 2016年第3期25卷 17-24页

作者： Stefan SCHAFFner Martin THALHEIM Lisa FREITAG Jana HUBLKOV Christos G.ANEZIRIS TU Bergakademie Freiberg

In the present study the fabrication of graded coarse grained ceramic bodies for refractory applications was investigated using a pressure filtration cell,which uses pressurized air as the pressure medium. The pressure filtration cell was used to examine the influence of different ceramic raw materials,two dispersants,and of the particle size distribution on the filtration behavior and on the filter cake surface quality. Pressure slip casting of spinel based slips resulted in crack-free filter cakes,while alumina based slips resulted in filter cakes,which always stuck on the used PMMA filter medium. Furthermore,citric acid as an electrostatic dispersant resulted in a much lower filtration cake resistance and hence shorter filtration times than an electrosteric dispersant. A broader particle size distribution with a higher addition of the finest particle fraction caused an increase in the filter cake resistance but also yielded much better surface qualities. Finally,graded filter cakes with three layers of alumina rich magnesium aluminate spinel with a maximum grain size of 3 mm,1 mm,and 0. 5 mm,respectively,were fabricated. The computed X-ray analyzes indicated a perfect bonding between the three layers,which is a significant improvement to previous studies. However,the graded filter cakes exhibited frequently cracks at the bottom,which was probably caused by tensile stresses from the friction of the filter cakes with the pressure filtration cell. This will be further investigated in subsequent studies. The achieved results demonstrate thefeasibility to produce coarse grained oxide ceramics for refractory applications by pressure slip casting,which eventually allows the production of composites with tailored compositions,microstructure and functionality.

关键词： refractories composites pressure slipcasting X-ray computed tomography spinels

Effects of cadmium and copper on sialic acid levels in blood and brain tissues of Cyprinus carpio L.

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Journal of Coastal Life Medicine 2014年第9期2卷 673-678页

作者： Utku Güner Elvan Bakar Trakya University Faculty of ScienceDepartment of BiologyBalkan CampusEdirneTurkey Trakya University Faculty of PharmacyBalkan CampusEdirneTurkey

Objective:To investigate the effects of cadmium(Cd)and copper(Cu)on sialic acid levels of brain and blood tissues of Cyprinus carpio.Methods:Adult carps were exposed to 0.1,0.5 mg/L Cu,0.1,0.5 and 1.0 mg/L Cd and 0.1 mg/L Cu+0.1 mg/L Cd under static experiment conditions for 1 week.At the end of exposure period,heavy metal accumulations and sialic acid levels in blood and brain tissues of the test animals were analyzed.Results:Cu and Cd accumulated in tissues in a dramatically increasing dose-dependent manner.Sialic acids level of the fish exposed to 0.1,0.5 and 1.0 mg/L Cu and Cd and control grups for 1 week were 0.834,1.427,0.672,0.934,2.968,4.714 mg/mL respectively.The results also showed that Cu has an antagonistic effect on tissue sialic acid level.Conclusions:We propose that Cd and Cu make a complex with sialic acids of membranes in the tissues researched.This complex between metal ions and sialic acid migth account for the cellular toxicity based on Cu and Cd.

关键词： Carp Cyprinus carpio Copper Cadmium Sialic acid Blood Brain Metal accumulation

Neutron-antineutron oscillations in the deuteron studied with NN and ■N interactions based on chiral effective field theory

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Chinese Physics C 2020年第3期44卷 28-32页

作者： Johann Haidenbauer Ulf-G.Meiβner Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität Bonn53115 BonnGermany Tbilisi State University 0186 TbilisiGeorgia

Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and Wise.Possible reasons for the difference are discussed.

关键词： neutron-antineutron oscillations chiral effective field theory NN interaction antinucleon-nucleon interaction

Crescentic glomerulonephritis in children:a single centre experience

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世界儿科杂志:英文版 2016年第2期12卷 225-230页

作者： Sare GülfemÖzlü AysunÇaltık Özlem Aydoğ Mehmet Bülbül Gülay Demircin EvrimÇakıcı Nilüfer Arda AyşeÖner Department of Pediatric Nephrology Dr Sami Ulus Childrens and Maternity HospitalAnkaraTurkey Department of Pathology Sami Ulus Childrens and Maternity HospitalAnkaraTurkey

Background:Crescentic glomerulonephritis(CsGN)is characterized by crescents in 50%or more of glomeruli and clinically by a sudden and progressive decline in renal function.Methods:We evaluated the etiology,clinical features,prognostic factors and long-term outcome of CsGN.Between January 2000 and December 2010,45 children(26 girls,19 boys)with biopsy-proven CsGN(>50%crescents)were investigated retrospectively.Results:The mean age of the patients was 130.86±33.77 months.The mean duration of symptoms prior to diagnosis was 26±12 days(4-40 days).Most of the children had hypertension(62.2%),macroscopic hematuria(73.3%),oligoanuria(44.4%),edema(51.1%)and purpuric rash(40%)at presentation.The final clinical status of the patients was complete remission(n=21),partial remission(n=5)or chronic kidney disease(n=19).Adverse outcomes were significantly associated with a long duration between the onset of symptoms and treatment(P=0.038),the presence of oligoanuria(P=0.006),a severe decreased glomerular filtration rate(GFR75%)(P=0.03),and the ratio of fi brous crescents(P=0.015).Conclusion:The outcome of CsGN in children continues to be poor,and it should be treated as a renal emergency.

关键词： glomerulonephritis renal biopsy renal failure

Does Stem Cell Implantation Have an Effect on Severity of Retinitis Pigmentosa: Evaluation with a Classification System?

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Open Journal of Ophthalmology 2021年第1期11卷 36-48页

作者： Ayşe Öner Neslihan Sinim Kahraman Ophthalmology Department Acibadem Kayseri Hospital Kayseri Turkey

Background: Cell replacement therapies have been evaluated in recent years as an alternative for various retinal pathologies to evaluate the therapeutic efficacy of cell therapy, it is important to measure the severit... 详细信息

rong>Background:rong> Cell replacement therapies have been evaluated in recent years as an alternative for various retinal pathologies to evaluate the therapeutic efficacy of cell therapy, it is important to measure the severity of the disease. The aim of this study was to evaluate the effect of umbilical cord derived Mesenchymal Stem Cell (UC-MSC) implantation on severity of Retinitis Pigmentosa (RP). rong>Methods:rong> This single-center, clinical study included data of 138 eyes of 92 patients who had a confirmed diagnosis of RP and received stem cell implantation to the suprachoroidal area with a surgical procedure. Patients were evaluated before and 1 year after the surgery regarding to the outcome measures of Best Corrected Visual Acuity (BCva), Optical Coherence Tomography (OCT) and Visual Field (VF) tests. BCva, VF width and ellipsoid zone (EZ) width on OCT were recorded for each patient and a scoring criterion was established for each variable varying from 0 to 5 depending on its distribution. The cumulative score (from 0 to 15) was used to classify disease severity from grade 0 to 5. rong>Results:rong> All of the patients completed 12-month follow-up period. The median age of the patients was 40.8 years, 46% were female, 77% had been diagnosed within 10 years and 41% had a family history. 79% of the patients with family history had autosomal recessive inheritance pattern. There were statistically significant improvements in the mean BCva and VF scores during the study (p roved after the treatment (p va improvement and scoring and grading of the disease. rong>Conclusions:rong> This study demonstrated beneficial effect of suprachoroidally applied UC-MSCs on BCva, VF and the severity score and grade of the disease during 12-month follow-up period. Cell mediated therapy based on the secretion of Growth Factors (GFs) seems to be an effective and safe option for the

关键词： Cell Mediated Therapy Retinitis Pigmentosa Suprachoroidal Implantation Umbilical Cord Derived Mesenchymal Stem Cell Visual Function Classification