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Spatial analysis of Dengue through the reproduction numbers relating to socioeconomic features:Case studies on two Brazilian urban centers

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Infectious Disease Modelling 2024年第1期9卷 142-157页

作者： Ana T.C.Silva Rejane C.Dorn lívia R.Tomás leonardo B.l.Santos lacita M.Skalinski Suani T.R.Pinho Departamento de Física Universidade Estadual de Feira de SantanaAv.Transnordestinas/n.Novo HorizonteFeira de Santana44036-900BABrazil Instituto de Física Universidade Federal da BahiaRua Barão de Jeremoabo s/nCampus Universitário de OndinaSalvador40170-115BABrazil Centro Nacional de Monitoramento e Alertas de Desastres Naturais(CEMADEN) Estrada Dr.Altino Bondensan500São Josédos Campos12247-016SPBrazil Universidade Estadual de Santa Cruz Campus Soane Nazaréde AndradeRodovia Jorge AmadoKm 16SalobrinhoIlhéus45662-900BABrazil Instituto de Saúde Coletiva Universidade Federal da BahiaR.Basílio da Gamas/n-CanelaSalvador40110-140BABrazil Instituto Nacional de Ciência e Tecnologia-Sistemas Complexos Virtual InstitutionBrazil

The study of the propagation of infectious diseases in urban centers finds a close connection with their population's social characteristics and *** work performs a spatial analysis of dengue cases in urban centers based on the basic reproduction numbers,R0,and incidence by planning areas(PAs),as well as their correlations with the Human Development Index(HDI)and the number of *** analyzed dengue epidemics in 2002 at two Brazilian urban centers,Belo Horizonte(BH)and Rio de Janeiro(RJ),using PAs as spatial *** results reveal heterogeneous spatial scenarios for both cities,with very weak correlations between R0 and both the number of trips and the HDI;in BH,the values of R0 show a less spatial heterogeneous pattern than in *** BH,there are moderate correlations between incidence and both the number of trips and the HDI;meanwhile,they weakly correlate for ***,the absence of strong correlations between the considered measures indicates that the transmission process should be treated considering the city as a whole.

关键词： Dengue Mathematical mode lbasic reproduction number Urban mobility Urban indices

高选择性H_(2)O_(2)光合成:ba原子注入面内高度有序结晶结构的g-C_(3)N_(4)纳米棒

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Chinese Journal of Catalysis 2024年第5期60卷 231-241页

作者：孟爱云马辛源温达钟威周双苏耀荣深圳技术大学新材料与新能源学院广东深圳518118

过氧化氢(H_(2)O_(2))是一种重要的绿色氧化剂,在医疗、军工、食品和绿色化学合成等领域有着广泛应用.然而,传统蒽醌法合成H_(2)O_(2)存在能耗高、污染严重等问题.光催化合成H_(2)O_(2)技术,利用来源丰富的太阳能实现氧气的两电子还原,... 详细信息

过氧化氢(H_(2)O_(2))是一种重要的绿色氧化剂,在医疗、军工、食品和绿色化学合成等领域有着广泛应用.然而,传统蒽醌法合成H_(2)O_(2)存在能耗高、污染严重等问题.光催化合成H_(2)O_(2)技术,利用来源丰富的太阳能实现氧气的两电子还原,被认为是替代蒽醌工艺的理想方案.石墨相氮化碳(g-C_(3)N_(4))因具有成本低、化学性质稳定和电子结构易调等优点,在光催化合成H_(2)O_(2)方面展现出很大潜力.但传统g-C_(3)N_(4)的面内结晶度低,且对两电子氧还原反应的选择性差,这极大地限制了其光合成H_(2)O_(2)效率.为解决这一难题,本文合理设计了一种新策略:将钡(ba)原子注入面内高度有序结晶结构的g-C_(3)N_(4)纳米棒(BI-CN),在增强g-C_(3)N_(4)的面内结晶度的同时,进一步提高其对两电子氧还原反应的选择性.本文采用baCl2诱导的面内聚合策略,实现了ba原子注入的面内高度有序结晶结构g-C_(3)N_(4)纳米棒的可控合成.在合成过程中,三聚氰胺分子选择性地吸附在baCl2的(200)晶面,并与暴露在baCl2表面的ba原子形成ba-N键.这种强相互作用诱导了三嗪结构单元的定向富集和聚合,从而形成面内有序结晶结构的g-C_(3)N_(4)结构.同时,ba原子通过ba-N键稳定地锚定在g-C_(3)N_(4)结构中,构建了ba原子注入的面内高度有序结晶结构的g-C_(3)N_(4)纳米棒.实验和理论计算结果表明,由于ba原子和N原子的电负性差异,电子从ba原子迁移到N原子,形成缺电子的ba活性位点.注入的ba原子起到正电荷中心的作用,氧气分子以Pauling构型稳定地吸附在ba原子上,该吸附构型使得O-O键不易断裂并增强了*OOH中间体的稳定性,从而抑制了四电子氧还原生成水的反应,有效地提高了两电子氧还原的选择性,最终实现高效的光催化H_(2)O_(2)合成.其中,最优的BI-CN3(三聚氰胺和baCl2质量比为9:2)光催化生成H_(2)O_(2)的速率达到353μmol l^(-1) h^(-1),是原始g-C_(3)N_(4)的6.1倍,且表现出良好的光催化循环使用性能.同时,BI-CN3光催化剂表现出更强的表面光电压信号、光电流信号以及更低的荧光强度,表明其具有更强的光生电荷分离和迁移效率.综上,本文不仅为构建具有面内高结晶度和原子级活性位点的g-C_(3)N_(4)光催化剂提供了一种新策略,还为提高两电子氧还原反应的选择性提供了新思路,可为光催化H_(2)O_(2)的高效、绿色合成提供了参考.

关键词： H_(2)O_(2)光合成石墨相氮化碳 ba原子注入高选择性两电子氧还原面内高结晶度

拉盖尔-高斯模叠加而成的部分相干光的相干涡旋

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物理学报 2007年第5期56卷 2623-2628页

作者：刘普生吕百达四川大学激光物理与化学研究所成都610064

对Bogatyryova等人近来提出的一种可分离位相的部分相干光的相干涡旋作了详细研究.这类新的光束由相同角向指数的拉盖尔-高斯(lG)模非相干叠加而成.研究表明,叠加lG模式的模指数,权重因子和参考点位置的选择都会影响圆刃型位错出现的位... 详细信息

对Bogatyryova等人近来提出的一种可分离位相的部分相干光的相干涡旋作了详细研究.这类新的光束由相同角向指数的拉盖尔-高斯(lG)模非相干叠加而成.研究表明,叠加lG模式的模指数,权重因子和参考点位置的选择都会影响圆刃型位错出现的位置,使得涡旋消失或出现多个相干涡旋.而且,lG模叠加而成的位相不可分离的部分相干光也存在相干涡旋.

关键词：奇点光学一类新的部分相干光束相干涡旋圆刃型位错

Why Sustainable Porous Carbon Should be Further Explored as Radar-Absorbing Material? A Comparative Study with Different Nanostructured Carbons

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Journal of Renewable Materials 2024年第10期12卷 1639-1659页

作者： Alan F.N.Boss Manuella G.C.Munhoz Gisele Amaral-labat Rodrigo G.A.lima leonardo I.Medeiros Nila C.F.l.Medeiros Beatriz C.S.Fonseca Flavia l.Braghiroli Guilherme F.B.lenz e Silva Department of Metallurgical and Materials Engineering University of de São PauloAvenida Mello MoraesCidade UniversitáriaSão PauloSP 05508-030Brazil Coordination of Applied Research and Technological Development National Institute for Space ResearchAvenida dos AstronautasJardim da GranjaSão Josédos CamposSP 12227-010Brazil Department of Exact and Technological Sciences Santa Cruz State UniversityRodovia Jorge Amadokm16IlhéusBA 45662900Brazil Institut de recherche sur les forêts Universitédu Québec en Abitibi-TémiscamingueRouyn-Noranda445 Bd de l’UniversitéRouyn-NorandaQC J9X 5E4Canada

Radar Absorbing Materials(RAM)are a class of composites that can attenuate incident electromagnetic waves to avoid radar *** carbon allotropes that have the potential to be used as RAM are either carbon nano-tubes(CNTs),graphene,carbon black(CB)and ultimately,sustainable porous carbon(SPC).Here,black wattle bark waste(following tannin extraction)was used as a sustainable source to produce SPC made from biomass *** was characterized and used as aﬁller for a silicone rubber matrix to produce aﬂexible *** elec-tromagnetic performance of this composite was compared with composites made with commercial CB and CNT through reﬂection loss(Rl),where-10 dB is equivalent to 90%of *** composites were evaluated in single-layer,double-layer,and as radar absorbing structures(RAS)with the aim of improving their effective absorption bandwidth(EAB)performances and a reduction in *** CNT composite presented a Rl of-26.85 dB at 10.89 GHz and an EAB of 2.6 GHz with a 1.9 mm thickness,while the double-layer structures using CNT and SPC provided a Rl of-19.74 dB at 10.75 GHz and an EAB of 2.51 ***,the double-layer structures are~42%cheaper than the composite using only CNT since less material is ***,the largest EAB was achieved with a RAS using SPC,reaching~2.8 GHz and a Rl of-49.09 dB at 10.4 ***,SPC made of black wattle bark waste can be a competitive,alternative material for use as RAM and RAS since it is cheaper,sustainable,and suitable for daily life uses such as absorbers for anechoic chambers,sensors,and elec-tromagnetic interference shields for electronics,wallets,vehicles,and others.

关键词： Microwave absorption material tannin waste dielectric constant carbon composite reﬂectivity

Somatic embryogenesis and plant regeneration in Betula platyphalla

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Journal of Forestry Research 2021年第3期32卷 937-944页

作者： Jingli Yang da Yang Wanqiu lü Xin Zhang Miaomiao Ma Guifeng liu Jing Jiang Chenghao li State Key laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China

Betula platyphylla is a native tree species in northern China that has high economic and medicinal *** developed an efficient protocol for the induction of somatic embryogenesis in *** from immature zygotic embryos and assessed the effects of explant type,genotype,and plant growth regulators(PGRs)on embryogenic callus *** the various explants evaluated,embryogenic callus was only produced from mature and immature zygotic embryos on medium with added 2,4-dichlorophenoxyacetic acid(2,4-D).Supplementation of 2,4-D-containing medium with cytokinins increased the frequency of embryogenic callus *** the 20 days after pollination,immature zygotic embryos that had been collected in mid-May yielded embryogenic tissue at the highest frequency(16.8%)when cultured on half-strength MS medium supplemented with 2.0 mg l^(-1)2,4-D and 0.2 mg l^(-1)6-benzylaminopurine(6-ba).The process of proliferation of embryogenic callus,somatic embryo formation,and subsequent plantlet conversion occurred under optimal culture *** regenerated plants weretransplanted to soil,95%of them developed normally and grew *** somatic embryogenesis system required 3–4 months for the regeneration of *** plantlets from immature zygotic embryos.

关键词： Betula platyphalla Somatic embryo Embryogenic callus Immature embryo

激光增材制造316l不锈钢退火过程中微观组织演变和力学性能

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金属热处理 2024年第4期49卷 66-77页

作者：郑磊徐达鲁宇杰廖文超殷安民陈候宁波大学机械工程与力学学院浙江宁波315211 浙江省零件轧制成形技术研究重点实验室浙江宁波315211

利用扫描电镜(sem)、电子背散射衍射(EBSD)、拉伸试验机研究了激光增材制造316 l不锈钢退火过程中的微观组织演变和力学性能。结果表明:在700℃退火后,鱼鳞状熔池形貌开始随着温度的升高逐渐转变为不规则长条状形貌,在750℃退火后,熔池... 详细信息

利用扫描电镜(sem)、电子背散射衍射(EBSD)、拉伸试验机研究了激光增材制造316 l不锈钢退火过程中的微观组织演变和力学性能。结果表明:在700℃退火后,鱼鳞状熔池形貌开始随着温度的升高逐渐转变为不规则长条状形貌,在750℃退火后,熔池内胞状和长条柱状亚结构转变为球形亚结构组织和三角形的点状凹坑形组织。随着退火温度的升高,晶粒尺寸先减小后增大,位错密度重新排序,胞状亚结构的溶解,亚结构组织,变形组织和大小角度晶界的演变反映着位错密度的降低,导致强度的下降和塑性的增强。在600℃×120 min退火时屈服强度为484.2 MPa,抗拉强度为665.6 MPa,伸长率为47.7%,在850℃×120 min退火时屈服强度为410.4 MPa,抗拉强度为639.1 MPa,伸长率为59.7%;随着保温时间的延长,变形组织转变为亚结构组织;在650℃温度下保温时间由30 min增加到120 min时,亚结构组织由24.1%增多到82.3%;在850℃温度下保温时间由30 min增加到120 min时,亚结构组织由24.9%增多到59.2%。

关键词：激光增材制造 316l不锈钢退火处理微观组织力学性能

Intensive peatland wildfires during the Aptian-Albian oceanic anoxic event 1b:Evidence from borehole SK-2 in the Songliao basin,NE China

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Journal of Palaeogeography 2022年第3期11卷 448-467页

作者： Zhi-Hui Zhang da-Wei lü Tian-Tian Wang Dong-Zhao An Hai-Yan liu Dong-Dong Wang Cheng-Shan Wang Shandong Provincial Key laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Institute of Earth Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Chinese Academy of Geological Sciences Beijing 100037China

The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock *** mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial ***,our understanding is still limited on changes in wildfire activity during OAE1b ***,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao basin,Northeast *** negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of ***,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that *** addition,Sr/ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of *** climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich *** results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.

关键词： lower Cretaceous OAEs Peatland Wildfire Coals

Near-UV light assisted green reduction of graphene oxide films through l-ascorbic acid

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International Journal of Smart and Nano Materials 2021年第1期12卷 20-35页

作者： Jaime Regis Sebastian Vargas Andrea Irigoyen Elsa Bramasco-Rivera Jose l.bañuelos luis C.Delfin Anabel Renteria Ulises Martinez Tommy RockwardYirong lin Department of Mechanical Engineering The University of Texas at El PasoEl PasoTX USA W.M.Keck Center for 3D Innovation the University of Texas at El PasoEl PasoTX USA Department of Physics The University of Texas at El PasoEl PasoTX USA Materials Physics and Applications Los Alamos National LaboratoryLos AlamosNM USA Department of Mechanical Engineering The University of Texas At El Paso 500 W.University Ave.El Paso TX 79968United States

Recent studies have highlighted the effects of various stimuli on the chemical reduction of graphene oxide(GO)through green reductant l-ascorbic acid(l-AA);however,the combination of near ultraviolet(NUV)light to increase the reduction rate has yet to be thoroughly *** this study,drop-casted GO films were subjected to chemical reduction through l-AA with various levels of exposure under 405 nm NUV *** structure and uniformity of GO stackings that form the film were characterized through scanning electron microscopy(sem)and wide-angle x-ray scattering(WAXS).Additionally,WAXS was used to track the removal of oxygen-containing functional groups along with Fourier-transform infrared(FT-IR)spectroscopy and x-ray photoelectron spectroscopy(XPS)as a function of l-AA and NUV light exposure *** results demonstrated that the interaction between l-AA and NUV exposure has a significant effect on the reduction of ***,the results that yielded the highest reduction(C-C bond concentration of 60.7%)were the longest l-AA and NUV light exposure times(48 hours and 3 hours,respectively).This report provides a study on the effects of NUV on the green reduction of GO films through l-AA with potential application in solar energy and chemical sensing applications.

关键词： Graphene Oxide Films Green Reduction Near Ultraviolet light l-Ascorbic Acid Wide-Angle X-Ray Scattering

baTiO_(3)/g-C_(3)N_(4)复合材料的制备及压电光催化性能研究

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陶瓷学报 2024年第1期45卷 117-124页

作者：邢子翱赵慧珍庆达王建省曾雄丰华北理工大学材料科学与工程学院河北省无机非金属材料实验室河北唐山063210 河北省(唐山)陶瓷产业技术研究院河北唐山063007

采用ba(OH)_(2)·8H_(2)O、TiO_(2)通过水热—煅烧法制备四方相baTiO_(3)。以三聚氰胺为前驱体,热缩聚法制备g-C_(3)N_(4)。简单研磨制备不同质量分数baTiO_(3)/g-C_(3)N_(4)压电光催化复合材料。采用X射线衍射(XRD)、扫描电镜(sem)、... 详细信息

采用ba(OH)_(2)·8H_(2)O、TiO_(2)通过水热—煅烧法制备四方相baTiO_(3)。以三聚氰胺为前驱体,热缩聚法制备g-C_(3)N_(4)。简单研磨制备不同质量分数baTiO_(3)/g-C_(3)N_(4)压电光催化复合材料。采用X射线衍射(XRD)、扫描电镜(sem)、紫外—可见漫反射吸收光谱(UV-Vis)对样品结构、形貌、光学性能进行表征。在模拟太阳光与超声波作用下降解罗丹明(Rh B),研究了复合材料的压电光催化性能。结果表明:10%baTiO_(3)/g-C_(3)N_(4)光吸收性能最好,压电光催化性能最优,100 min内对Rh B降解率为97.81%,是g-C_(3)N_(4)降解速率的1.48倍。捕获剂实验表明,压电光催化条件下·OH与·O_(2)^(-)为主要活性物种。

关键词：钛酸钡类石墨相氮化碳压电光催化