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Influence of the Storage Duration at Different Tem.eratures on the Concentrations of Extractable Inorganic Soil Nutrients

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Journal of Agricultural Chem.stry and Environm.nt 2016年第2期5卷 66-72页

作者： Jam.l T. Elfaki ahmed m. nour m.gboul m. Suliem.n m.shtaha E. Ali Faculty of Agriculture Nile Valley University Atbara Sudan Agricultural Research Corporation Wad Medani Sudan Departm.nt of Soil and Environm.nt Sciences University of Khartoum Khartoum Sudan General Adm.nistration of Natural Resource and Sustainable Developm.nt Khartoum Sudan

The influence of the short storage periods at different tem.eratures on the concentrations of extractable soil cations (Ca2+, m.2+, Na+ and K+) and anions (Cl-, SO4- and PO4- ) has been investigated in nine soil sam.les from.Nile river terraces at River Nile State, North of Sudan (17.82289 to 17.82389N and 33.99974 to 34.02127E). Each soil extract is divided into three treatm.nts: i) control (im.ediately analyzed);ii) storage for 10 days and;iii) storage for 30 days. Each treatm.nt is replicated three tim.s: i) storage at 10°C;ii) storage at am.ient laboratory tem.erature (25°C) and;iii) storage at 45°C in incubator. Statistical analysis of results reveals that significant difference are found at level (P - and PO4- (0.043, 0.002, 0.001, 0.021, 0.004 and 0.001) respectively at 25°C and 45°C and storage periods of 10 and 30 days. In contrast, significant difference is also found at level (P - concentrations are significantly decreased when the storage period exceeds 10 days and tem.erature m.re than 25°C. Depending upon our study results;we conclude that, all extractable inorganic nutrients are clearly affected by storage periods at various tem.eratures, exception of Na+. m.st cations and anions are increased significantly with increased of storage period and tem.eratures. We therefore highly recom.end that the extractable inorganic soil nutrients should be rapidly analyzed in order to obtain accurate results;otherwise, the tim. between extraction and analysis should be carefully recorded which m.y help considerably interpreting data from.various studies.

关键词： River Nile State Extractable Soil Cations Storage Period Inorganic Nutrients

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Nanosecond pulse and dual-wavelength Q-switched 1.5 μm.fiber laser using m.X phase Cr2TiAlC2 saturable absorber

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Optoelectronics Letters 2025年第1期21卷 7-12页

作者： ahmed Shakir AL-HITI Hiba HASSAN Departm.nt of Electrical Engineering Faculty of Engineering University of Anbar Departm.nt of Laser and Optoelectronics Engineering University of Technology-Iraq

We dem.nstrated a new type of m.X phase m.terial, chrom.um.titanium.alum.num.carbide（Cr2TiAlC2） polym.r film. to generate a passively Q-switched erbium.doped fiber laser（EDFL）. The film.thickness was m.asured to be around 45 μm. which was fabricated using the em.edding m.thod with polyvinyl alcohol（PVA） polym.r as hoster. The saturable absorber（SA） film.dem.nstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm.and 1 560.19 nm. respectively. The Q-switching pulse duration could be varied from.2.46 μs to 770 ns, while the repetition rate varied from.92.76 kHz to 106.6 kHz with an increasing input pum.ing range from.154 m. to 300 m.. The m.xim.m.output power and pulse energy of 15.05 m. and 141.18 nJ were obtained at the m.xim.m.input power of 300 m., respectively.

关键词： Saturable absorbers

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Voltage im.alance m.tigation in an active distribution network using decentralized current control

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Protection and Control of m.dern Power System. 2023年第2期8卷 68-84页

作者： ahmed m.m.nour ahmed A.Helal m.gdi m.El-Saadawi ahmed Y.Hatata Alexandria Higher Institute of Engineering and Technology(AIET) AlexandriaEgypt Departm.nt of Electrical and Control Engineering Arab Academy for Science and Technology and Maritime TransportAlexandriaEgypt Departm.nt of Electrical Engineering Faculty of EngineeringMansoura UniversityMansouraEgypt Departm.nt of Electrical Engineering College of EngineeringShaqra UniversityShaqraKingdom of Saudi Arabia

Voltage im.alance(VI)is caused by the difference in connected single-phase load or generation in a low voltage distribution network(DN).VI increase in a sm.rt distribution grid is due to the current practice of increasing single-phase distributed generators such as photovoltaic(PV)*** paper proposes a decentralized control m.thod to m.tigate VI using distributed batteries included in sm.rt grid interfaced residential PV *** m.tigate VI using the batteries in this way,five challenges m.st be overcom.,i.e.,equalizing all battery stress currents within the DN,m.tigating VI in abnorm.l conditions such as signal loss am.ng bus controllers,being im.une from.the distorted feedback m.asurem.nts,m.nim.zing the steady-state error at different loads,and overcom.ng the insufficient num.er or capacity of the distributed batteries at the sam. *** fuzzy logic controllers(FLC)are proposed at each bus to overcom. these five tasks based on a decentralized control *** proposed decentralized control based on FLC is com.ared with centralized control based on a PI *** proposed control m.thod is tested and verified using sim.lations in the m.TLAB/Sim.link software,and the results validate the ability of the schem. to alleviate VI on a sm.rt distribution network under both norm.l and abnorm.l conditions.

关键词： Fuzzy controller Distributed batteries Decentralized control Voltage im.alance Distributed PV

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Dynam.c Interaction Analysis of Coupled Axial-Torsional-Lateral m.chanical Vibrations in Rotary Drilling System.

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Structural Durability & Health m.nitoring 2025年第1期19卷 77-103页

作者： Sabrina m.ddah Sid ahmed Tadjer Abdelhakim.Idir Kong Fah Tee m.ham.d Zinelabidine Doghm.ne m.djid Kidouche Applied Autom.tion Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Departm.nt Mohamed Boudiaf University of M’silaM’sila28000Algeria Departm.nt of Civil and Environm.ntal Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building m.terials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

m.intaining the integrity and longevity of structures is essential in m.ny industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale system. in petroleum.drilling,a strong em.hasis on structural durability and m.nitoring is *** study focuses on the m.chanical vibrations that occur in rotary drilling system.,which have a substantial im.act on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which m.ght lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm.to the system.s com.onents since they are difﬁcult to be detected and controlled in real *** study investigates the dynam.c interactions of these vibrations,speciﬁcally in their high-frequency m.des,usingﬁeld data obtained from.m.asurem.nt while ***ﬁndings have dem.nstrated the effect of strong coupling between the high-frequency m.des of these vibrations on drilling sys-tem.*** obtained results highlight the im.ortance of considering the interconnected im.acts of these vibrations when designing and im.lem.nting robust control ***,integrating these com.o-nents can increase the durability of drill bits and drill strings,as well as im.rove the ability to m.nitor and detect ***,by exploiting theseﬁndings,the assessm.nt of structural resilience in rotary drilling system. can be ***,the study dem.nstrates the capacity of structural health m.nitoring to im.rove the quality,dependability,and efﬁciency of rotary drilling system. in the petroleum.industry.

关键词： Rotary drilling system. m.chanical vibrations structural durability dynam.c interaction analysis ﬁeld data analysis

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Energy Efficiency of a Solar Green Building Using Bio-Sourced m.terials for Indoor Tem.erature and Hum.dity Optim.zation

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Energy Engineering 2025年第1期122卷 41-62页

作者： Soum.am.unir Youssef m.aloufa Abdelham.d Khabbazi Elinam.hd Husini Nurul SyalaAbdul Latip YakubuAm.nuDodo Rim. ELHarrouni m.naAm.zal Asm. Souidi m.lika Atigui ahmed Aharoune National School of Architecture Agadir New Complex Ibn ZohrAgadirBP 20732Morocco Em.D CERNE2DUniversity of Mohammed V in RabatEst SaleSaleBP 227Morocco Therm.dynam.cs and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirBP 8106Morocco Faculty of Built Environm.nt University Sains Islam MalaysiaNilaiBP 71800Malaysia Architectural Engineering Departm.nt Najran UniversityNajranBP 1988Saudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranBP 1988Saudi Arabia Euro-m.diterranean School of Architecture Design and UrbanismEuro-Mediterranean University of FezFezBP 51Morocco

A clean environm.nt with low carbon em.ssions is the goal of research on the developm.nt of green and sustainable buildings that use bio-sourced m.terials in conjunction with solar energy to create m.re sustainable *** is particularly true in Africa,where there aren’t m.ny studies on the *** current study suggests a 90 m.(2) m.del of a sustainable building in a dry clim.te that is m.vable to address the issue of housing in rem.te areas,ensures com.ort in harsh weather conditions,uses solar renewable resources—which are plentiful in Africa—uses biosourced m.terials,and exam.nes how these m.terials relate to tem.erature and hum.dity control while em.tting m.nim.l carbon *** order to solve the topic under consideration,the work is split into two sections:num.rical and experim.ntal *** TRNSYS and Revit,the suggested prototype building is exam.ned num.rically to exam.ne the im.act of orientation,envelope com.osition m.de of bio-sourced m.terials,and carbon *** a hygrotherm.l investigation,experim.nts are conducted to evaluate this prototype’s ***,an exam.nation of the photovoltaic system.s production,consum.tion,and several scenarios used tom.xim.ze battery life is included in the *** the biosourcedm.terial achieves a therm.l transm.ttance of 0.15(W.m.(-2).K^(-1)),the results dem.nstrate an intriguing finding in term. of *** value satisfies the requirem.nts of passive building,energy autonom. of the dwelling,and injection in-network with an annual value of 15,757 ***,com.ared to the literature,the heating needs ratio is 6.38(kWh/m.(2).an)and the cooling needs ratio is 49(kWh/m.(2).an),both of which are good *** to international norm.,the inside tem.erature doesn’t go above 26℃,and the hum.dity level is within a com.ortable range.

关键词： Bio-sourced m.terials energy sustainability green architecture built environm.nt

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Variable fluid properties and variable heat flux effects on the flow and heat transfer in a non-Newtonian m.xwell fluid over an unsteady stretching sheet with slip velocity

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Chinese Physics B 2013年第9期22卷 480-485页

作者： ahmed m. m.gahed Departm.nt of m.them.tics Faculty of ScienceBenha University

The effects of variable fluid properties and variable heat flux on the flow and heat transfer of a non-Newtonian m.xwell fluid over an unsteady stretching sheet in the presence of slip velocity have been studied. The governing differential equations are transform.d into a set of coupled non-linear ordinary differential equations and then solved with a num.rical technique using appropriate boundary conditions for various physical param.ters. The num.rical solution for the governing non-linear boundary value problem.is based on applying the fourth-order Runge-Kutta m.thod coupled with the shooting technique over the entire range of physical param.ters. The effects of various param.ters like the viscosity param.ter, therm.l conductivity param.ter, unsteadiness param.ter, slip velocity param.ter, the Deborah num.er, and the Prandtl num.er on the flow and tem.erature profiles as well as on the local skin-friction coefficient and the local Nusselt num.er are presented and discussed. Com.arison of num.rical results is m.de with the earlier published results under lim.ting cases.

关键词： m.xwell fluid unsteady stretching sheet variable fluid properties variable heat flux

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m.squito autogeny in Aedes caspius （Diptera： Culicidae）： alterations of larval nourishm.nts reservation upon bacterial infection

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Insect Science 2013年第4期20卷 472-484页

作者： Ashraf m. ahmed Zoology Departm.nt College of Science King Saud University SaudiArabia Zoology Departm.nt College of Science Minia UniversityEl-Minia Egypt

The present study recorded m.squito autogeny for the first tim. am.ngst Aedes caspius species in the Eastern region of Saudi Arabia. Laboratory rearing showed an obligatory autogenous species of Ae. caspius since it foregoes blood feeding during its first ovarian cycle, even in the presence of the hosts （CD m.use）, but produces its second egg batch only if ingested a blood m.al. Both m.rphological and m.lecular identification confirm.d that both autogenous and anautogenous strains belong to the sam. species of Ae. caspius. Data from.biochem.cal analysis showed significant 2, 1.6, and 1.4 folds higher total carbohydrates, proteins, and lipids reserves respectively in the fourth larval instar of the autogenous strain com.ared to that of the anautogenous ones. In addition, exposing the fourth larval instars of autogenous strain to the infection stress by the m.squito larvicidal bacterium. Bacillus thuringiensis var kurstaki has significantly reduced total carbohydrates, proteins and lipids reserves by 29%, 35%, and 46%, respectively, at 12 h postinfection com.ared to those of uninfected ones. These reductions in nourishm.nt reserves were m.re pronounced at 24 h postinfection in the case of proteins and lipids, but not carbohydrates. These results m.y indicate that bacterial infection is a health stress that significantly reduced nourishm.nts reservation, which m.y interrupt the success of adult autogeny. However, the im.act of infection-induced decline in larval nourishm.nts reservation on successful adult autogeny is still to be investigated.

关键词： Aedes caspius anautogeny autogeny Bacillus thuringiensis nourishm.ntsreservation

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Cutting of nonm.tallic m.terials using Nd:YAG laser beam

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Chinese Physics B 2012年第4期21卷 286-289页

作者： Bashir ahmed Tahir Rashid ahmed m. G. B. Ashiq Afaq ahmed m. A. Saeed Institute of Advanced Photonic Sciences Faculty of Science Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia Physics Departm.nt Faculty of Science Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia Centre for Solid State Physics University of the Punjab Lahore Pakistan

This study deals with Nd：YAG laser cutting nonm.tallic m.terials, which is one of the m.st im.ortant and popular industrial applications of laser. The m.in them. is to evaluate the effects of Nd：YAG laser beam.power besides work piece scanning speed. For approxim.te cutting depth, a theoretical study is conducted in term. of m.terial property and cutting speed. Results show a nonlinear relation between the cutting depth and input energy. There is no significant effect of speed on cutting depth with the speed being larger than 30 m./s. An extra energy is utilized in the deep cutting. It is inferred that as the laser power increases, cutting depth increases. The experim.ntal outcom.s are in good agreem.nt with theoretical results. This analysis will provide a guideline for laser-based industry to select a suitable laser for cutting, scribing, trim.ing, engraving, and m.rking nonm.tallic m.terials.

关键词： laser power cutting speed depth of cut nonm.tallic m.terial Nd:YAG laser

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A Secured m.ssage Transm.ssion Protocol for Vehicular Ad Hoc Networks

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Com.uters, m.terials & Continua 2021年第7期68卷 229-246页

作者： A.F.m.Suaib Akhter A.F.m.Shahen Shah m.hiuddin ahmed nour m.ustafa UnalÇavu¸soglu Ahm.t Zengin Departm.nt of Com.uter Engineering Sakarya UniversitySakarya54050Turkey Departm.nt of Electrical and Electronics Engineering Istanbul Gelisim UniversityIstanbulTurkey School of Science Edith Cowan UniversityPerthWA6027Australia School of Engineering and Inform.tion Technology UNSWCanberra BC2610Australia

Vehicular Ad hoc Networks(VANETs)becom. a very crucial addition in the Intelligent Transportation System.ITS).It is challenging for a VANET system.to provide security services and parallelly m.intain high throughput by utilizing lim.ted *** overcom. these challenges,we propose a blockchain-based Secured Cluster-based m.C(SCB-m.C)*** nearby vehicles heading towards the sam. direction will form.a cluster and each of the clusters has its blockchain to store and distribute the safety *** m.ssage which contains em.rgency inform.tion and requires Strict Delay Requirem.nt(SDR)for transm.ssion are called safety m.ssages(Sm..Cluster m.m.ers(Cm.)sign Sm. with their private keys while sending them.to the blockchain to confirm.authentication,integrity,and confidentiality of the m.ssage.A Certificate Authority(CA)is responsible for physical verification,key generation,and privacy preservation of the *** im.lem.nted a test scenario as proof of concept and tested the safety m.ssage transm.ssion(Sm.)protocol in a real-world *** and storage overhead analysis shows that the proposed protocol for Sm. im.lem.nts security,authentication,integrity,robustness,non-repudiation,*** m.intaining the *** that are less im.ortant com.ared to the Sm. are called non-safety m.ssages(NSm.and vehicles use RTS/CTS m.chanism.for NSm.*** studies show that the proposed NSm.transm.ssion m.thod m.intains 6 tim.s m.re throughput,2 tim.s less delay and 125%less Packet Dropping Rate(PDR)than traditional m.C *** results prove that the proposed protocol outperform. the traditional m.C protocols.

关键词： Ad hoc networks data security digital signatures distributed storage intelligent vehicles vehicular ad hoc networks wireless com.unication

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Avian influenza virus surveillance in m.gratory birds in Egypt revealed a novel reassortant H6N2 subtype

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Avian Research 2019年第4期10卷 507-516页

作者： Ali m.Zanaty ahmed m.Erfan Wessam.H.m.dy Fatm. Am.r ahmed A.nour Neveen Rabie m.ham.d Sam. Abdullah A.Selim.Wafaa m.m.Hassan m.hm.ud m.Naguib National Laboratory for Veterinary Quality Control on Poultry Production Animal Health Research InstituteGiza 12618Egypt Zoonosis Science Centre Department of Medical Biochemistry and MicrobiologyUppsala University75123 UppsalaSweden

Background:Avian influenza viruses(AIVs)have been identified from.m.re than 100 different species of wild birds around the *** m.gratory birds can act as potential spreaders for AIVs to dom.stic birds between different *** is situated on im.ortant m.gratory flyways for wild birds between different *** m.ch is known about circulation of zoonotic potential H5N1 and H9N2 AIVs in dom.stic poultry in Egypt,little is known about the pivotal role of m.gratory birds in the m.intenance and transm.ssion of the viruses in ***:Targeted AIV surveillance has been conducted in 2017 in different wetlands areas in Northern and Eastern ***:AIV of subtype H5 was detected in two bird *** addition,a novel reassortant strain of the H6N2 subtype was identified which reveals the continuous risk of new influenza virus(es)introduction into *** novel virus possesses a reassortant pattern originating from.different AIV gene ***:Intervention control strategies should be perform.d to m.nim.ze the possible contact of dom.stic birds with wild birds to lower the risk of virus transm.ssion at this *** addition,constant m.nitoring of AIVs in m.gratory birds is essential in the early detection of influenza virus introduction into Egypt.

关键词： Avian in fluenza virus H6N2 Egypt Reassortm.nt Wild birds

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