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Advances in Chem.cal Engineering and Science 2014年第3期4卷 300-307页

作者： isaac m. cohen Sandra Siri m.ria C. Fornaciari Iljadica Centro Atom.co Ezeiza Comision Nacional de Energia Atomica Ezeiza Argentina Centro Atóm.co Ezeiza Comisión Nacional de Energía Atómica Ezeiza Argentina Facultad Regional Avellaneda Universidad Tecnológica Nacional Avellaneda Argentina

The studies perform.d in the fram. of a project destined for the search of new (t,n) and (p,n) reactions of interest in nuclear reactors are described. Experim.ntal evidences of the observations of the reactions: 46Ti(t,n)48V, 48Ti(p,n)48V, 52Cr(t,n)54m., 56Fe(p,n)56Co, 72Ge(t,n)74As and 74Ge(p,n)74As, are presented. Additional data on som. secondary reactions, already characterised for the production of 7Be, 56Co, 58Co, 65Zn and 88Y, were also obtained. The significance of these data is discussed.

关键词： Nuclear Reactions Nuclear Reactors Tritons Recoil Protons

m.tion of charged particles in bright squeezed vacuum

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Light(Science & Applications) 2024年第2期13卷 347-353页

作者： m.tan Even Tzur Oren cohen Solid State Institute and Physics Departm.nt Technion-Israel Institute of TechnologyHaifa3200003Israel

The m.tion of laser-driven electrons quivers with an average energy term.d ponderm.tive *** explore electron dynam.cs driven by bright squeezed vacuum.BSV),finding that BSV induces width oscillations,akin to electron quivering in laser light,with an equivalent ponderom.tive *** identify closed and open trajectories of the electronic width that are associated with high harm.nic generation and above-threshold ionization,respectively,sim.larly to trajectories of the electron position when its m.tion is driven by coherent *** the case of bound electrons,the width oscillations m.y lead to ionization with noisy sub-cycle *** results are foundational for strong-field and free-electron quantum.optics,as they shed light on ionization,high harm.nic generation,and nonlinear Com.ton scattering in BSV.

关键词： structure vacuum ionization

m.them.tical m.deling of the Co-Infection Dynam.cs of HIV and Tuberculosis Incorporating Inconsistency in HIV Treatm.nt

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Journal of Applied m.them.tics and Physics 2024年第5期12卷 1744-1768页

作者： Sr m.ry Nyam.ura m.angi Virginia m. Kitetu isaac O. Okwany Departm.nt of m.them.tics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

A non-linear HIV-TB co-infection has been form.lated and analyzed. The positivity and invariant region has been established. The disease free equilibrium.and its stability has been determ.ned. The local stability was determ.ned and found to be stable under given conditions. The basic reproduction num.er was obtained and according to findings, co-infection dim.nishes when this num.er is less than unity, and persists when the num.er is greater than unity. The global stability of the endem.c equilibrium.was calculated. The im.act of HIV on TB was established as well as the im.act of TB on HIV. Num.rical solution was also done and the findings indicate that when the rate of HIV treatm.nt increases the latent TB increases while the co-infected population decreases. When the rate of HIV treatm.nt decreases the latent TB population decreases and the co-infected population increases. Encouraging com.unities to prioritize the consistent treatm.nt of HIV infected individuals m.st be em.hasized in order to reduce the scourge of HIV-TB co-infection.

关键词： Co-Infection m.deling HIV-TB Co-Infection m.them.tical m.deling Reproduction Num.er Inconsistent Treatm.nt

m.them.tical m.deling of HIV Investigating the Effect of Inconsistent Treatm.nt

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Journal of Applied m.them.tics and Physics 2024年第4期12卷 1063-1078页

作者： Sr m.ry Nyam.ura m.angi Virginia m. Kitetu isaac O. Okwany Departm.nt of m.them.tics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

HIV is a retrovirus that infects and im.airs the cells and functions of the im.une system. It has caused a great challenge to global public health system. and leads to Acquired Im.unodeficiency Syndrom. (AIDS), if not attended to in good tim.. Antiretroviral therapy is used for m.naging the virus in a patient’s lifetim.. Som. of the sym.tom. of the disease include lean body m.ss and m.ny opportunistic infections. This study has developed a SIAT m.them.tical m.del to investigate the im.act of inconsistency in treatm.nt of the disease. The arising non-linear differential equations have been obtained and analyzed. The DFE and its stability have been obtained and the study found that it is locally asym.totically stable when the basic reproduction num.er is less than unity. The endem.c equilibrium.has been obtained and found to be globally asym.totically stable when the basic reproduction num.er is greater than unity. Num.rical solutions have been obtained and analyzed to give the trends in the spread dynam.cs. The inconsistency in treatm.nt uptake has been analyzed through the num.rical solutions. The study found that when the treatm.nt rate of those infected increases, it leads to an increase in treatm.nt population, which slows down the spread of HIV and vice versa. An increase in the rate of treatm.nt of those with AIDS leads to a decrease in the AIDS population, the reverse happens when this rate decreases. The study recom.ends that the com.unity involvem.nt in advocating for consistent treatm.nt of HIV to curb the spread of the disease.

关键词： HIV m.deling m.them.tical m.deling Reproduction Num.er Inconsistent Treatm.nt

Colorful facial m.rkings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish

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Current Zoology 2024年第1期70卷 70-78页

作者： Brett m.Culbert Jam.s B.Barnett isaac Y.Ligocki m.tthew G.Salena m.rian Y.L.Wong Ian m.Ham.lton Sigal Balshine Departm.nt of Integrative Biology University of GuelphGuelphOntarioCanada Departm.nt of Psychology Neuroscience&BehaviourMcMaster UniversityHamiltonOntarioCanada Departm.nt of Evolution Ecologyand Organismal BiologyThe Ohio State UniversityColumbusOHUSA Departm.nt of Biology Millersville UniversityMillersvillePAUSA School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia Departm.nt of m.them.tics The Ohio State UniversityColumbusOHUSA

m.ny anim.ls use color to signal their quality and/or behavioral *** signals have been well studied in the contexts of com.eti-tion and m.te choice;however,the role of these signals in nonsexual,affiliative relationships is not as well ***,we used wild social groups of the cichlid fish Neolam.rologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dom.nance,and/or 3)affiliative *** with larger patches spent m.re tim. foraging and tended to perform.m.re aggressive acts against conspecific territory *** did not find any evidence that the size of these yellow patches was related to social rank or body size,but dom.nant m.les tended to have larger patches than dom.nant ***,patch size had a rank-specific relationship with the num.er of affiliative interactions that individuals engaged *** m.les with large patches received fewer affiliative acts from.their groupm.tes com.ared to dom.nant m.les with sm.ll ***,subordinates with large patches tended to receive m.re affiliative acts from.their groupm.tes while perform.ng fewer affiliative acts *** together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer som. of the first evidence that colorful signals m.y shape affiliative relationships withinwildsocialgroups.

关键词： affiliation foraging Lake Tanganyika Neolam.rologus pulcher visual signals

Photoelectrochem.cal Iron-Catalyzed C(sp^(3))-H Borylation of Alkanes in a Position-Selective m.nner

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CCS Chem.stry 2024年第6期6卷 1430-1438页

作者： Wen Wei Bin Wang Sim.n L.Hom.lle Jinbin Zhu Yanjun Li Tristan von m.nchow isaac m.ksso Lutz Ackerm.nn Institut für Organische und Biom.lekulare Chem.e Georg-August-Universität Göttingen37077 Göttingen

Catalytic C-H borylation is of prim. topical im.ortance,since easily available feedstock chem.cals can thereby be transform.d into valuable transient functional groups in the absence of directing ***,we disclose an iron-catalyzed C(sp^(3))-H borylation of sim.le,non-prefunctionalized alkanes,providing access to value-added products in a single step by m.ans of *** power of m.rging photo-and electrochem.stry was m.rrored by am.le scope and exceedingly m.ld reaction ***,an outstanding position-selectivity in favor of prim.ry C(sp^(3))-H proved viable within the photoelectrochem.cal borylation through a chem.-selective anodic overoxidation *** ferro-photoelectrochem.stry strategy avoids toxic precious transition m.tals,enabling C(sp^(3))-H borylations in a site-selective fashion.

关键词： photoelectrocatalysis C(sp^(3))-H borylation iron catalysis position-selectivity chlorine radical

Etching-free pixel definition in InGaN green m.cro-LEDs

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Light(Science & Applications) 2024年第8期13卷 1655-1665页

作者： Zhiyuan Liu Yi Lu Haicheng Cao Glen isaac m.ciel Garcia Tingang Liu Xiao Tang Na Xiao Raul Aguileta Vazquez m.ngtao Nong Xiaohang Li Advanced Sem.conductor Laboratory Electrical and Computer Engineering ProgramCEMSE DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia

The traditional plasm. etching process for defining m.cro-LED pixels could lead to significant sidewall *** near sidewall regions act as non-radiative recom.ination centers and paths for current leakage,significantly deteriorating device *** this study,we dem.nstrated a novel selective therm.l oxidation(STO)m.thod that allowed pixel definition without undergoing plasm. dam.ge and subsequent dielectric *** annealing in am.ient air oxidized and reshaped the LED structure,such as p-layers and InGaN/GaN m.ltiple quantum.***,the pixel areas beneath the pre-deposited SiO_(2)layer were selectively and effectively *** was dem.nstrated that prolonged therm.l annealing tim. enhanced the insulating properties of the oxide,significantly reducing LED leakage ***,applying a thicker SiO_(2)protective layer m.nim.zed device resistance and boosted device efficiency *** the STO m.thod,InGaN green m.cro-LED arrays with 50-,30-,and 10-μm.pixel sizes were m.nufactured and *** results indicated that after 4 h of air annealing and with a 3.5-μm.SiO_(2)protective layer,the 10-μm.pixel array exhibited leakage currents density 1.2×10^(-6)A/cm.(2)at-10 V voltage and a peak on-wafer external quantum.efficiency of~6.48%.This work suggests that the STO m.thod could becom. an effective approach for future m.cro-LED m.nufacturing to m.tigate adverse LED efficiency size effects due to the plasm. etching and im.rove device ***-LEDs fabricated through the STO m.thod can be applied to m.cro-displays,visible light com.unication,and optical interconnect-based *** planar pixel geom.try will provide m.re possibilities for the m.nolithic integration of driving circuits with ***,the STO m.thod is not lim.ted to m.cro-LED fabrication and can be extended to design other III-nitride devices,such as photodetectors,laser diodes,high-electron-m.bility transistors

关键词： annealing protective quantum

System.tic Radio Telescope Alignm.nt Using Portable Fringe Projection Profilom.try

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Nanom.nufacturing and m.trology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong isaac Pim.enta Rachel Ball Wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook Kim Jam.s C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Departm.nt of Astronom. at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever im.ge of a black hole event *** are now aim.ng for higher angular resolutions of distant targets,like black holes,to understand m.re about the fundam.ntal laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilom.ter Array(SKA)require building hundreds of telescopes with diam.ters greater than 10 m. over the next *** has a twofold *** telescope surfaces need to be m.re accurate to operate at higher frequencies,and the logistics involved in m.intaining a radio telescope need to be sim.lified to support them.properly in large *** of these problem. can be solved with im.roved m.thods for surface m.trology that are faster and m.re accurate with a higher *** leads to faster and m.re accurate panel alignm.nt and,therefore,a m.re productive *** this paper,we present the use of binocular fringe projection profilom.try as a solution to this problem.and dem.nstrate it by aligning two panels on a 3-m.radio telescope *** m.asurem.nt takes only 10 m.n and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： m.trology Fringe projection profilom.try Off-axis alignm.nt Radio astronom. Radio antenna

Design and Developm.nt of a Parabolic Trough Solar Air Heater for a Greenhouse Dryer

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Journal of Power and Energy Engineering 2024年第9期12卷 1-18页

作者： Eric King’ori isaac N. Sim.te Departm.nt of m.chanical Engineering The University of Zambia Lusaka Zambia Departm.nt of Agricultural Engineering The University of Zambia Lusaka Zambia

Design and Developm.nt of a Parabolic Trough Solar Air Heater (PTSAH) for a Greenhouse Dryer (GD) was done to im.rove the dryer’s perform.nce. The m.terials used for the fabrication of the PTSAH included galvanized sheets covered with alum.nium.foil, an absorber tube m.de of GI pipe painted m.tt black to increase heat absorbance at the focal line, m.ld steel square tubes, shutter plywood, and an axial fan to push air through the absorber tube. Key geom.trical param.ters used for the design of the PTSAH were a rim.angle of 98 degrees, focal length of 0.2608 m. height of 0.3451 m. length of 2 m. and an aperture width of 1.2 m. The PTSAH’s total aperture surface area was 2.4 m., while its absorber tube surface area was 0.1587 m.. The PTSAH was experim.ntally tested to establish its therm.l perform.nce. It was found that the am.ient air recorded an average value of 31.1˚C and that the air heater could increase the air tem.erature by 45.6˚C above am.ient with a therm.l efficiency of 5.3%. It can, therefore, be concluded that the PTSAH can significantly im.rove the perform.nce of a GD by supplying the GD with air at a higher tem.erature than am.ient.

关键词： Solar Air Heater Greenhouse Dryer Parabolic Trough Therm.l Perform.nce

基于TROPOm. NO_(2)、CO及HCHO重构数据的近地面O_(3)浓度估算研究

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遥感学报 2024年第9期28卷 2348-2361页

作者：陈小娟秦凯 cohen Jason 何秦中国矿业大学环境与测绘学院徐州221116

以TROPOm.大气成分产品为代表的卫星遥感数据在近地面臭氧(O_(3))浓度估算中表现出很好的潜力。由于云及反演算法局限性等原因,TROPOm.的大气成分产品存在一定的数据缺失,使得基于此的近地面O_(3)浓度估算数据覆盖度较低。为此,本文采... 详细信息

以TROPOm.大气成分产品为代表的卫星遥感数据在近地面臭氧(O_(3))浓度估算中表现出很好的潜力。由于云及反演算法局限性等原因,TROPOm.的大气成分产品存在一定的数据缺失,使得基于此的近地面O_(3)浓度估算数据覆盖度较低。为此,本文采用经验正交函数分解插值法(DINEOF)对TROPOm. NO_(2)、CO、HCHO原始数据产品进行缺失像元重构,并基于重构数据产品采用极限梯度提升算法(XGBoost)估算了中国大陆地区2019年—2021年高覆盖度的日最大8 h平均O_(3)浓度(m.A8 O_(3))。对比研究了DINEOF方法对TROPOm. NO_(2)、CO、HCHO原始数据产品的缺失像元进行重构后再建模估算O_(3)的方法(方案1),使用TROPOm. NO_(2)、CO、HCHO原始数据产品并对其缺失像元赋空值并输入其他特征变量来建模估算O_(3)的方法(方案2),有TROPOm. NO_(2)、CO、HCHO原始数据产品的建模结果和无TROPOm. NO_(2)、CO、HCHO原始数据产品,只有其他特征变量的建模结果相结合的方法(方案3),均可提升O_(3)模型估算结果的覆盖度。实验表明:方案1的结果最好,其十折交叉验证R^(2)=0.86,Rm.E=15.86μg/m.(3),模型精度和方案2基本一致且高于方案3,在重构区域的模型精度最高(训练集R^(2)=0.82,Rm.E=15.57μg/m.(3)),且当重构区域出现O_(3)重污染时(浓度大于160μg/m.(3)),能明显改善模型高值低估现象,结果的空间分布更合理。方案1估算的2019年—2021年近地面m.A8 O_(3)的平均覆盖度从33.6%提升到97.2%,使用TROPOm. NO_(2)、CO、HCHO重构数据产品建模估算O_(3)可提升模型性能和模型结果的覆盖度。

关键词：遥感近地面O_(3) TROPOm. DINEOF XGBoost 数据重构