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SEIRS model for malaria transmission dynamics incorporating seasonality and awareness campaign

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Infectious Disease Modelling 2024年第1期9卷 84-102页

作者： francis Oketch Ochieng Department of Pure and Applied Mathematics Jomo Kenyatta University of Agriculture and TechnologyNairobi62000-00200Kenya

Malaria,a devastating disease caused by the Plasmodium parasite and transmitted through the bites of female Anopheles mosquitoes,remains a significant public health concern,claiming over 600,000 lives annually,predominantly among *** tools,including the application of Wolbachia,are being developed to combat malaria-transmitting *** study presents a modified susceptible-exposed-infectious-recovered-susceptible(SEIRS)compartmental mathematical model to evaluate the impact of awareness-based control measures on malaria transmission dynamics,incorporating mosquito interactions and *** the next-generation matrix approach,we calculated a basic reproduction number(R0)of 2.4537,indicating that without robust control measures,the disease will persist in the human *** model equations were solved numerically using fourth and fifth-order Runge-Kutta *** model was fitted to malaria incidence data from Kenya spanning 2000 to 2021 using least squares curve *** fitting algorithm yielded a mean absolute error(MAE)of 2.6463 when comparing the actual data points to the simulated values of infectious human population(Ih).This finding indicates that the proposed mathematical model closely aligns with the recorded malaria incidence *** optimal values of the model parameters were estimated from the fitting algorithm,and future malaria dynamics were projected for the next *** research findings suggest that social media-based awareness campaigns,coupled with specific optimization control measures and effective management methods,offer the most cost-effective approach to managing malaria.

关键词： SEIRS model Malaria transmission dynamics Model fitting Basic reproduction number Stability analysis Seasonality Awareness campaign Runge–Kutta method

Synthesis of nanostructured zinc oxide and its composite with carbon dots for DSSCs applications using flexible electrode

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Materials Reports(Energy) 2024年第3期4卷 77-83页

作者： Habtamu Fekadu Etefa francis Birhanu Dejene Department of Physics Walter Sisulu UniversityPrivate Bag X-1Mthatha5117South Africa

ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods *** were also characterized and applied for dye sensitized solar cells(DSSCs).The effects of C-dots on ZnO NWs and ZnO NPs have been *** C-dots were used at a mole ratio of citric acid(CA)to ethylene diamine(EDA)of 1:*** C-dots were found to enhance the performance of the flexible electrode *** the addition of C-dots,the power conversion efficiency(PCE)of ZnO NPs was boosted to be two times higher than that of ZnO NPs DSSCs without ***,the ultraviolet(UV)-band revealed a blue shift,resulting in a lower band gap and a reduced charge transfer resistance,which can enhance the PCE of *** loaded quantity on the flexible electrode substrate made of polyethylene terephthalate(PET)was optimized(50 mg).For DSSCs,the PET flexible electrode conductive polymer has produced positive *** ZnO NWs and ZnO NWs@C-dots,the PCE values were 1.45%and 4.25%;while for ZnO NPs and ZnO NPs@C-dots,they were 2.34%and 5.81%,*** work achieved remarkable and competitive performance when compared to solid(indium tin oxides/glass)-based substrate.

关键词： ZnO NWs@C-dots ZnO NPs@C-dots PET DSSCs Flexible electrode

The Potential Game-Changer:A Concept-to-Proof Study on D:A Heterojunction-Free Organic Photovoltaics

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Chinese Journal of Chemistry 2024年第3期42卷 252-258页

作者： Lijian Zuo Sae Byeok Jo Xueliang Shi francis Lin Alex Jen State Key Laboratory of Silicon and Advanced Semiconductor Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Department of Materials Science and Engineering University of WashingtonSeattleWAUSA School of Chemical Engineering Sungkyunkwan University (SKKU)Suwon16419 Republic of Korea School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062 China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of Chemistry City University of Hong KongKowloonHong KongChina Hong Kong Institute for Clean Energy Hong KongChina

Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关键词： Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component

Doped low-density parity-check codes

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Digital Communications and Networks 2024年第1期10卷 217-226页

作者： Yong Li Rui Liu Xianlong Jiao Youqiang Hu Zhen Luo francis C.M.Lau College of Computer Science Chongqing UniversityChongqing400044China School of Automation Chongqing UniversityChongqing400044China College of Electronic and Information Engineering Southwest UniversityChongqing400715China Future Wireless Networks and IoT Focusing Area Department of Electronic and Information EngineeringHong Kong Polytechnic UniversityHong KongChina

In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-Check(LDPC)*** doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LDPC ***,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is *** results demonstrate that the proposed doped LDPC code achieves up to 2.0 dB gain compared with the original LDPC code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LDPC Codes.

关键词： LDPC codes Doped LDPC codes Tanner graph Quadratic residue codes Trapping sets

Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： francis Levi A.DURANO Jon Marx SARMIENTO Larry N.DIGAL Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting

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International Journal of Extreme Manufacturing 2024年第1期6卷 340-351页

作者： Yang Sha Menghui Zhu Kun Huang Yang Zhang francis Moissinac Zhizhou Zhang Dongxu Cheng Paul Mativenga Zhu Liu Department of Materials School of Natural SciencesThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Laser Processing Research Centre Department of MechanicalAerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom National Graphene Institute The University of ManchesterOxford RoadManchester M139PLUnited Kingdom Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Research Centre for Laser Extreme Manufacturing Ningbo Institute of Materials Engineering and TechnologyChinese Academy of SciencesNingboPeople’s Republic of China

Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water *** address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of ***,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE *** electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·*** the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially *** addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water *** combination exhibits excellent durability under industrial current *** energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal *** LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production.

关键词： electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate

Hybrid ionic/electronic interphase enabling uniform nucleation and fast diffusion kinetics for stable lithium metal anode

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Chinese Chemical Letters 2024年第2期35卷 626-633页

作者： Lun Li Pengxia Ji Meng Huang Zixin Zhang Hong Wang francis Verpoort Jinlong Yang Daping He State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Guangdong Research Center for Interfacial Engineering of Functional Materials College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China Sanya Science and Education Innovation Park of Wuhan University of Technology Sanya 572000China Hubei Engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

Lithium(Li)dendrite issue,which is usually caused by inhomogeneous Li nucleation and fragile solid electrolyte interphase(SEI),impedes the further development of high-energy Li metal ***,the integrated construction of a high-stable SEI layer that can regulate uniform nucleation and facilitate fast Li-ion diffusion kinetics for Li metal anode still falls ***,we designed an artificial SEI with hybrid ionic/electronic interphase to regulate Li deposition by in-situ constructing metal Co clusters embedded in LiF *** generated Co and LiF both enable fast Li-ion diffusion kinetics,meanwhile,the lithiophilic properties of Co clusters can serve as Li-ion nucleation sites,thereby contributing to uniform Li nucleation and non-dendritic *** a result,a dendrite-free Li deposition with a low overpotential(16.1 mV)is achieved,which enables an extended lifespan over 750 h under strict *** full cells with high-mass-loading LiFePO_(4)(11.5 mg/cm^(2))as cathodes exhibit a remarkable rate capacity of 84.1 mAh/g at 5 C and an improved cycling performance with a capacity retention of 96.4%after undergoing 180 cycles.

关键词： Lithium metal anode Hybrid ionic/electronic interphase Solid electrolyte interphase Fast diffusion kinetics Dendritic growth of lithium

Understanding the catalysis of chromium trioxide added magnesium hydride for hydrogen storage and Li ion battery applications

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Journal of Magnesium and Alloys 2024年第3期12卷 1117-1130页

作者： D.Pukazhselvan IhsanÇaha Catarina de Lemos Sergey M.Mikhalev francis Leonard Deepak Duncan Paul Fagg Department of Mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal Nanostructured Materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRD)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO *** free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EDS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt *** is also convincing ground to consider that MgO rock salt accommodates Cr in the *** observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.

关键词： Hydrogen storage Rechargeable batteries Binary hydrides Metal oxides Catalytic mechanism.

Modelling and Characterization of Basalt/Vinyl Ester/SiC Micro-and Nano-hybrid Biocomposites Properties Using Novel ANN–GA Approach

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Journal of Bionic Engineering 2024年第2期21卷 938-952页

作者： Yesudhasan Thooyavan Lakshmi Annamali Kumaraswamidhas Robinson Dhas Edwin Raj Joseph Selvi Binoj Bright Brailson Mansingh Antony Sagai francis Britto Alamry Ali Department of Mechanical Engineering Indian Institute of Technology Dhanbad(ISM)DhanbadJharkhand826004India Gati Shakti Vishwavidyalaya(GSV-A Central University Funded By GoI in the Ministry of Railways) LalbaugVadodaraGujarat390004India Institute of Mechanical Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(SIMATS)Saveetha UniversityChennaiTamilnadu602105India Metal Joining Research Centre Department of Mechanical EngineeringSri Ramakrishna Engineering CollegeCoimbatoreTamilnadu641022India Department of Mechanical Engineering Rohini College of Engineering and TechnologyPalkulamTamil Nadu629401India Department of Mechanical Engineering College of Engineering in Al-KharjPrince Sattam Bin Abdulaziz University11942Al-KharjSaudi Arabia

Basalt fiber reinforcement in polymer matrix composites is becoming more and more popular because of its environmental friendliness and mechanical qualities that are comparable to those of synthetic *** fiber strengthened vinyl ester matrix polymeric composite with filler addition of nano-and micro-sized silicon carbide(SiC)element spanning from 2 weight percent to 10 weight percent was studied for its mechanical and wear *** application of Artificial Neural Network(ANN)to correlate the filler addition composition for optimum mechanical properties is required due to the non-linear mechanical and tribological features of *** stuffing blend and composition of the composite are optimized using the hybrid model and Genetic Algorithm(GA)to maximize the mechanical and wear-resistant *** predicted and tested ANN–GA optimal values obtained for the composite combination had a tensile,flexural,impact resilience,hardness and wear properties of 202.93 MPa,501.67 MPa,3.460 J/s,43 HV and 0.196 g,respectively,for its optimum combination of filler and *** can be noted that the nano-sized SiC filler particle enhances most of the properties of the composite which diversifies its *** predicted mechanical and wear values of the developed ANN–GA model were in closer agreement with the experimental values which validate the model.

关键词： Hybrid polymer composite Prediction Process modelling Artificial neural networks Genetic algorithm