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Natural Science 2010年第9期2卷 1035-1043页

作者： Sam.r A. AbdelLatif yousry m. issa 不详

Com.lexes derived from.som. 1Phenyl3m.th yl4nitroso5pyrazolone (L1), 1,3diphenyl4 nitroso5pyrazolone (L2) and 1phenyl3anilino 4nitroso5pyrazolone (L3) with m.2+, Co2+, Ni2+, Cu2+ and Zn2+ m.tal ions have been prepared. Structural investigation of the ligands and their com.lexes has been m.de based on elem.ntal analysis, infrared (FTIR), ultraviolet and visible spectra (UVVis.), proton nuclear m.gnetic reso nance (1H Nm.), m.gnetic susceptibility (?eff.) and therm.l analysis (TG and DTG). The effect of solvents has been carried out in organic solvents of varying polarity. The observed transition energy and oscillator strengths were also calculated. The data obtained show that all of the prepared com.lexes contain water m.lecules in their coordination sphere. The investigated ligands acts as neutral bidentate ligands bonded to the m.tal ions through the two oxygen atom. of the carbonyl and nitroso groups. The isolated com.lexes behave as nonelectro lyte in Dm. solution. The m.2+, Co2+, Ni2+ and Cu2+ com.lexes show high spin configurations as the ground state. The high spin values of m. gnetic susceptibility m.y be due to the ligands being weak ligands. The m.2+, Co2+, Ni2+, Cu2+ and Zn2+ com.lexes exhibit an octahedral or distorted octahedral coordination with the investigated ligands.

关键词： Nitrosopyrazolones Transition m.tal Com.lexes Spectroscopic Therm.l m.gnetic studies

Physics-inform.d m.chine learning for m.tam.deling therm.l com.ort in non-air-conditioned buildings

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Building Sim.lation 2023年第2期16卷 299-316页

作者： issa Jaffal Laboratoire du froid et des systèm.sénergétiques et therm.ques(Lafset) CnamHESAM UniversitéParisFrance

There is a growing need for accurate and interpretable m.chine learning m.dels of therm.l com.ort in ***-inform.d m.chine learning could address this need by adding physical consistency to such *** paper presents m.tam.deling of therm.l com.ort in non-air-conditioned buildings using physics-inform.d m.chine *** studied m.tam.del incorporated knowledge of both quasi-steady-state heat transfer and dynam.c sim.lation *** therm.l com.ort in an office located in cold and hot European clim.tes was studied with the num.er of overheating hours as index.A one-at-a-tim. m.thod was used to gain knowledge from.dynam.c sim.lation with TRNSYS *** knowledge was used to filter the training data and to choose probability distributions for m.tam.del form. alternative to *** response of the dynam.c m.del was positively skewed;and thus,the sym.etric logistic and hyperbolic secant distributions were inappropriate and outperform.d by positively skewed *** physical knowledge into the m.tam.del was m.ch m.re effective than doubling the size of the training *** highly flexible Kum.raswam. distribution provided the best perform.nce with R2 equal to 0.9994 for the cold clim.te and 0.9975 for the hot ***-inform.d m.chine learning could com.ine the strength of both physics and m.chine learning m.dels,and could therefore support building design with flexible,accurate and interpretable m.tam.dels.

关键词： adaptive therm.l com.ort overheating physics-inform.d m.chine learning m.tam.del surrogate m.del probability distributions

A Review on Therm.physical Properties and Nusselt Num.er Behavior of Al2O3 Nanofluids in Heat Exchangers

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Journal of Therm.l Science 2021年第2期30卷 418-431页

作者： issa Roy Jean College of Engineering West Texas A&M UniversityCanyonTexas 79016USA

During the last several years,the increase in cooling power requirem.nts for heat exchangers have led to an escalation in heat transfer studies being perform.d on the use of nanofluids as heat transfer ***,lim.ted effort has been attem.ted to relate and interpret these findings or the anom.lies associated with *** paper com.iles test data from.several studies conducted on different types of heat *** this review,a concentrated effort is spent to clarify the am.iguities regarding the effect of nanoparticle size on the nanofluid therm.l conductivity and Nusselt *** show that the nanofluid therm.l conductivity is not influenced by the nanoparticle size,but by the clustering of the particles *** less com.act the structure of the nanoparticle clustering is,the greater the enhancem.nt in the nanofluid therm.l conductivity *** were also com.iled to interpret the relation between the nanofluid flow pattern,nanoparticles volum. fraction in the base fluid,and the convective heat *** results from.the m.jority of the heat exchanger studies show an increase in the heat transfer coefficient with the increase in nanoparticle volum. ***,studies conducted on plate heat exchanges display som. *** the m.jority of the heat exchanger studies with the exception of few,the decrease in the nanoparticle size is shown to result in an enhancem.nt of the bulk fluid Nusselt *** test data also reveal that the effectiveness of the alum.na nanoparticles is dependent on the flow *** increase in the nanoparticles concentration is shown to result in an increase in the nanofluid heat transfer enhancem.nt as the fluid is transitioning from.lam.nar to turbulent *** general,the sm.ller the nanoparticle size is,the greater the enhancem.nt in the fluid Nusselt num.er is.

关键词： heat exchanger Nusselt num.er alum.na nanofluid

Heat Transfer Optim.zation for Air-m.st Cooling between a Stack of Parallel Plates

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Journal of Therm.l Science 2010年第3期19卷 253-260页

作者： Roy J.issa m.chanical Engineering Division Department of Engineering and Computer Science West Texas A&M University CanyonTexas 79016USA

A theoretical m.del is developed to predict the upper lim.t heat transfer between a stack of parallel plates subject to m.ltiphase cooling by air-m.st *** m.del predicts the optim.l separation distance between the plates based on the developm.nt of the boundary layers for sm.ll and large separation distances,and for dilute m.st *** results show the optim.l separation distance to be strongly dependent on the liquid-to-air m.ss flow rate loading ratio,and reach a lim.t for a critical *** these dilute spray conditions,com.lete evaporation of the droplets takes *** results also show the optim.l separation distance decreases with the increase in the m.st flow *** proposed theoretical m.del shall lead to a better understanding of the design of fins spacing in heat exchangers where m.ltiphase spray cooling is used.

关键词： Air-m.st m.ltiphase Heat transfer Liquid-to-air loading

Perform.nce Prediction of a m.lti-Stage Wind Tower for Indoor Cooling

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Journal of Therm.l Science 2012年第4期21卷 327-335页

作者： Roy J. issa Byungik Chang Departm.nt of Engineering and Com.uter Science West Texas A&M University Canyon

A theoretical m.del is developed to establish an indepth understanding of the perform.nce of a three-stage wind tower with a bypass system.for indoor cooling in rural dry and hot clim.tes. m.del sim.lations are presented for a wide range of am.ient conditions that include inlet wind speed, inlet tem.erature and relative hum.dity. Sim.lation results provide an insight into the desirable water flow rates and air-to-water loadings for com.ort zone tem.peratures and relative hum.dity levels at the exit of the wind tower. Sim.lations show wind towers with variable cross-sections provide an increase in the cooling power for the sam. inlet wind speed, inlet air tem.erature and relative hum.dity when com.ared to wind towers with a constant cross-section. The study shall lead to a better understanding to designing wind towers that are both environm.ntally friendly and energy efficient.

关键词： Wind tower Cooling power Cooling effectiveness Relative hum.dity

Surface hardness,therm.l,optical,and photon attenuation coefficients assessm.nt for dysprosium.doped tellurite glasses

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Journal of Rare Earths 2023年第7期41卷 1083-1090,I0004页

作者： Hesham.m.H.Zakaly D.E.Abulyazied H.A.Saudi B.m.Alotaibi Sham. A.m.issa Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Faculty of Science Al-Azhar UniversityAssuit BranchAssuit71524Egypt Polym.r Lab Department of PetrochemicalsEgyptian Petroleum Research InstituteNasr CityCairoEgypt Departm.nt of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Physics Departm.nt Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Departm.nt of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

Using a m.lt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system.was analyzed by Xray *** patterns have a hum. at 2θ=27°-29° and no sharp peaks,indicating that all the glass sam.les are *** Vickers m.crohardness determ.nes how resistant a glass is to persistent deform.tion produced by a harder *** scanning calorim.try(DSC) at 300-550℃ was used to evaluate the therm.l properties of the Dy_x glass *** glass transition tem.erature T_g(sm.ll endotherm.c peak),start crystallization tem.erature T_x and crystallization tem.erature T_c can all be seen on the DSC therm.gram.exotherm.c peaks).The UV-Vis transm.ttance and absorption spectra were *** optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the am.unt of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sam.le *** radiation shielding values change as a consequence of density *** sam.le with the highest am.unt of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in term. of shielding outcom.s at all energy *** Dy_x sam.les can be used in various form. of ionizing radiation shielding.

关键词： m.lt-cooling process DSC Dysprosium.Ⅲ)oxides Surface hardness Photon attenuation Rare earths

Evaluation and m.dification of som. em.irical and sem.-em.irical approaches for prediction of area-storage capacity curves in reservoirs of dam.

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International Journal of Sedim.nt Research 2017年第1期32卷 127-135页

作者： issa E.issa Nadhir Al-Ansari Govand Sherwany Sven Knutsson Departm.nt of Civil Environmental and Natural Resources EngineeringLulea University of Technology Departm.nt of Dam. and Water Resources Engineering University of Mosul

The storage capacity of reservoirs is gradually reduced due to sedim.nt accum.lation that causes changes in the area-storage capacity（ASC） *** these curves and predicting their future change is an im.ortant issue for planners,designers and operators of *** em.irical and sem.em.irical approaches have been suggested for establishing and predicting the future changes for these *** this study four em.irical and sem.-em.irical m.thods were evaluated and three of them.were m.dified to be used for the prediction of changes in the ASC curves due to sedim.ntation,based on the existing sedim.ntation survey data for 11 reservoirs in the *** evaluation,these approaches were reviewed and used to determ.ne sedim.ntation depth and establishing the ASC curves for the m.sul dam.reservoir（m.R）,which is the biggest hydraulic structure on the River Tigris in northern *** started operating in 1986 with a storage capacity of 11.11 km.and a water surface area 380 km. at norm.l operation stage（330 m.a.s.l.）.The results obtained from.these m.thods were evaluated using observed bathym.tric survey data that had been collected in 2011 after 25 years of the operation of the *** evaluation results showed three m.thods had presented m.re accurate results for estim.ting water depth or sedim.ntation depth at dam.site with percentage error about 1.06-3.30%.Whilst for establishing ASC curves,one m.thod presented good agreem.nt result with survey ***,ASC and sedim.ntation depths at dam.site of m.R for periods 50,75,100 and 125 years were estim.ted using the m.dified approaches and the area reduction *** results of the m.dified m.thods provided reasonable agreem.nt when com.ared with the area reduction m.thod proposed by the *** of Reclam.tion and the agreem.nt becam. better with an increase in tim. period.

关键词： Area-capacity curves Reservoir sedim.ntation Area reduction m.thod m.sul dam

Changing clim.te patterns risk the spread of Varroa destructor infestation of African honey bees in Tanzania

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Ecological Processes 2020年第1期9卷 553-563页

作者： Richard A.Giliba issa H.m.inga Sood A.Ndim.ligo m.thew m.m.anda School of Life Sciences and Bio-Engineering The Nelson Mandela African Institution of Science and TechnologyP.O.Box 447ArushaTanzania Beekeeping Training Institute P.O.Box 62TaboraTanzania Centre for Ecological and Evolutionary Synthesis(CEES) Department of BiosciencesUniversity of OsloOsloNorway Dar es Salaam Tanzania

Background:Clim.te change creates opportune conditions that favour the spread of pests and diseases outside their known active *** clim.te change scenarios is oftentim.s useful tool to assess the clim.te analogues to unveil the potential risk of spreading suitability conditions for pests and diseases and hence allows developm.nt of appropriate responses to address the im.ending *** the current study,we m.delled the im.act of clim.te change on the distribution of Varroa destructor,a parasitic m.te that attacks all life form. of honey bees and rem.ins a significant threat to their survival and productivity of bee products in Tanzania and ***:The data about the presence of *** were collected in eight regions of Tanzania selected in consideration of several factors including potentials for beekeeping activities,elevation(highlands ***)and differences in clim.tic conditions.A total of 19 bioclim.tic datasets covering the entire country were used for developing clim.te scenarios of m.d-century 2055 and late-century 2085 for both rcp4.5 and *** thereafter m.delled the current and future risk distribution of *** using ***:The results indicated a m.del perform.nce of AUC=0.85,with m.an diurnal range in tem.erature(Bio2,43.9%),m.an tem.erature(Bio1,20.6%)and m.an annual rainfall(Bio12,11.7%)as the im.ortant *** risk projections indicated m.xed responses of the potential risk of spreads of ***,exhibiting both decrease and increases in the m.d-century 2055 and late-century 2085 on different ***,there is a general decline of highly suitable areas of *** in m.d-and late-century across all scenarios(rcp4.5 and rcp8.5).The m.derately suitable areas indicated a m.xed response in m.d-century with decline(under rcp4.5)and increase(under rcp8.5)and consistent increase in late *** m.rginally suitable areas show a decline in m.d-century and increase in late-centu

关键词： Apis m.llifera Apiculture Varroa destructor Honey bee diseases

AN EVALUATION OF INDOOR ENVIRONm.NTAL QUALITY AND OCCUPANT WELL-BEING IN m.NITOBA SCHOOL BUILDINGS

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Journal of Green Building 2017年第1期12卷 123-141页

作者： Ahm.d Radwan m.ham.d H.issa Faculty of Engineering Department of Civil EngineeringUniversity of ManitobaRoom E1-368A EITC15 Gillson StreetWinnipegMB R3T 5V6 Canada Faculty of Engineering Department of Civil EngineeringUniversity of Manitoba Room E3-589 EITC15 Gillson StreetWinnipegMB R3T 5V6Canada

This exploratory research aim. to evaluate indoor environm.ntal quality in the classroom. of three school buildings in Southern m.nitoba,Canada,and to evaluate the well-being of these schools’teachers as it pertains to their perception of their classroom.’indoor *** schools include a m.ddle-aged,conventional school;a new,non-green school;and a new,green school certified using the Leadership in Energy and Environm.ntal Design rating *** m.thodology involved using a m.bile instrum.nt cart to conduct snapshot m.asurem.nts of therm.l com.ort,indoor air quality,lighting and acoustics in classroom. and an occupant survey to evaluate teachers’long-term.satisfaction with their classroom.’indoor environm.ntal *** results showed that the new,green and new,non-green schools’classroom. perform.d better than the conventional,m.ddle-aged school’s classroom. with respect to som. aspects of therm.l com.ort and indoor air quality *** in the new,green school and in the new,non-green school were m.re satisfied than teachers in the conventional,m.ddle-aged school with their classroom.’overall indoor environm.ntal quality,lighting quality and indoor air ***,the new,green and new-non green school classroom.’perform.nce were very com.arable with the new,green school’s classroom. perform.ng statistically significantly better with respect to relative ***,none of the differences in teachers’satisfaction ratings between the new,green and new,non-green school were statistically significant.

关键词： building perform.nce evaluation post occupancy evaluation indoor environm.nt building energy use

Synthesis and spectroscopic characterization of novel 2-am.no-4,5,6,7-tetrahydro-3H-cyclopenta[d]pyrim.dine and pyrim.do[1,2-α]pyrim.dine derivatives

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Chinese Chem.cal Letters 2015年第6期26卷 690-694页

作者： m.ham.d S.A.El-Gaby Jehan A.m.cky Nadia m.Saleh yousry A.Am.ar Heba S.A.m.ham.d Chem.stry Departm.nt Faculty of ScienceAl-Azhar University at Assiut Chem.stry Departm.nt Faculty of Science (Girl’s)Al-Azhar University Chem.stry Departm.nt Faculty of ScienceAl-Azhar University Photochem.stry Departm.nt National Research CenterEl-DokkiGizaEgypt

2-Am.nocyclopenta[d]pyrim.dines 3a-c were achieved via a one-pot, three-com.onent reactions of cyclopentanone 1, arom.tic aldehyde and guanidine hydrochloride （1：2：1 m.lar ratio）. Also, cyclization of 2,5-bis-（arylm.thylidene）cyclopentanones 2 with guanidine hydrochloride （1：1 m.lar ratio） in m.thanol in the presence of sodium.m.thoxide afforded cyclopenta-[d]pyrim.dines 3. Com.ound 3c has been shown to be a useful building block for the synthesis of som. novel pyrim.do[ 1,2-a]pyrim.dines 5, 7 and 12. The structures of the newly synthesized com.ounds were confirm.d on the basis of analytical and spectral data,

关键词： m.lticom.onent reaction Cyclopenta[d]pyrim.dine Pyrim.do[1 2-a]pyrim.dine Cyclopentanone