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Advances in Atmospheric Sciences 1996年第3期13卷 349-358页

作者： S.M ei shazly Department of Physics.Faculty of Science South Valley UniversityQenaA.R.Egypt

The performance of two models,Jam and Baig,based on the modified version of Gaussian distribution function in estimating the daily total of global solar radiation and its distribution through the hours of the day from sunrise to sunset al any clear day is evaluated with our own measured data in the period from June 1992 to May 1993 in Qena Egypt The results show a high relative deviation of calculated values from measured ones,especially for Jain model,in the most hours of the day,except for those near to local *** misfit behavior is quite obvious in the early morning and late afternoon A new approach has been proposed in this paper to estimate the daily and hourly global solar radiation This model performs with very high accuracy on the recorded data in our *** validity of this approach was verified with new measurements in some clear days in June and August *** resultant very low relative deviation of the calculated values of global solar radiation from the measured ones confirms the high performance of the approach proposed in this work

关键词： Glohal solar radiation,. Measurements Models Gaussian distribution function Statistical treatment

Progressive collapse of 2D reinforced concrete structures under sudden column removal

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1387-1402页

作者： ei Houcine MOURID Said MAMOURI Adnan IBRAHIMBEGOVIC Mechanics of Structures Laboratory MechanicsModeling and Experimentation Laboratory.Department of Mechanical EngineeringUniversity of Tahri Mohamed-Bechar Bechar 08000Algeria Roberal Mechanics laboratory Alliance Sorbonne UniversiyCompiegne 60203France

Once a column in building is removed due to gas explosion,vehicle impact,terrorist attack,earthquake or any natural disaster,the loading supported by removed column transfers to neighboring structural *** these elements are unable to resist the supplementary loading,they continue to fail,which leads to progressive collapse of *** this paper,an efficient strategy to model and simulate the progressive collapse of multi-story reinforced concrete structure under sudden column removal is *** strategy is subdivided into several connected steps including failure mechanism creation,MBS dynamic analysis and dynamic contact simulation,the latter is solved by using conserving/decaying scheme to handle the stiff nonlinear dynamic *** effect of gravity loads,structure-ground contact,and structure-structure contact are accounted for as *** main novelty in this study consists in the introduction of failure function,and the proper manner to control the mechanism creation of a frame until its total ***,this contribution pertains to a very thorough investigation of progressive collapse of the structure under sudden column *** proposed methodology is applied to a six-story frame,and many different progressive collapse scenarios are *** results ilustrate the efficiency of the proposed strategy.

关键词： failure mechanism MBS dynamic analysis gravity loads structure-ground contact structure-structure contact energy conserving decaying scheme

Assessing the Suitability of Various Physiological Traits to Screen Wheat Genotypes for Salt Tolerance

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Journal of Integrative Plant Biology 2007年第9期49卷 1352-1360页

作者： Salah E. ei-Hendawy Yuncai Hu Urs Schmidhalter Chair of Plant Nutrition Technical University Munich D-85350 Freising-Weihenstephan Germany Agronomy Department Faculty of Agriculture Suez Canal University Ismalia Egypt

Success of improving the salt tolerance of genotypes requires effective and reliable screening traits in breeding programs. The objective was to assess the suitability of various physiological traits to screen wheat genotypes for salt tolerance. Thirteen wheat genotypes from Egypt, Germany, Australia and India were grown in soil with two salinity levels （control and 150 mmol/L NaCI） in a greenhouse. The physiological traits （ion contents in leaves and stems, i.e. Na^＋, Cl^-, K^＋, Ca^2＋）, the ratios of K^＋/Na^＋ and Ca^＋/Na^＋ in the leaves and stems, net photosynthesis rate, stomatal conductance, transpiration rate, chlorophyll content （SPAD value）, and leaf water relations, were measured at different growth stages. The physiological traits except for Na^＋ and Cl^- in stems and the leaf transpiration rate at 150 mmol/L NaCI showed a significant genotypic variation, indicating that the traits that have a significant genotypic variation may be possibly used as screening criteria. According to the analysis of linear regression of the scores of the physiological traits against those of grain yield, however, the physiological traits of Ca^2＋ and Ca2^＋/Na^＋ at 45 d and final harvest with the greatest genotypic variation were ranked at the top. From a practical and economic point of view, SPAD value should be considered to be used as screening criteria and/or there is a need to develop a quick and practical approach to determine Ca^2＋ in plant tissues.

关键词： physiological traits salinity screening wheat genotypes.

^14CO2 Fixation and Translocation of Photoassimilates as Selection Criteria of Egyptian Taro Genotypes

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Journal of Integrative Plant Biology 2006年第5期48卷 563-566页

作者： Helal Ragab Moussa Afaf Abd ei-Kader Salem Radioisotopes Department Atomic Energy Authority Cairo Egypt Horticultural Research Institute Agriculture Research Center Giza Egypt

The growth characterlstlcs, different physlological parameters, photosynthetic activity （^14CO2 fixation）, and the translocatlon rate of photoassimllates In different taro （Colocasia esculenta L. Schott） genotypes was studled In order to determlne the posslble use of these parameters as selectlon crlterla for dlfferent wldely used genotypes of taro （Delta No. 9, 15, 20, 21, and balady）. The results obtalned suggest that Delta No. 21 shows the most slgnlflcant increase In all parameters tested compared wlth the control （balady）, followed by Delta No. 9, 15, and 20, respectively. The results show a positive correlation between photosynthetlc actlvlty, translocatlon efflclency, and total yield. The selected clone Delta No. 21 Is recommended for cultlvatlon In the delta reglon of Egypt.

关键词： ^14CO2 fixation taro (Colocasia esculenta) translocation rate.

On large scale CFD-DEM simulation for gas-liquid-solid,three-phase flows

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Particuology 2021年第6期19卷 2-15页

作者： Kimiaki Washino ei L.Chan Tetsushi Kaji Yoshiaki Matsuno Toshitsugu Tanaka Department of Mechanical Engineering Osaka UniversitySuitaOsaka 565-0871Japan

Particulate flows in a mixture of gas and liquid,***-liquid-solid three-phase flows,are frequently encountered both in nature and *** such flows,complex interactions between multiple phases,***-particle interactions,fluid-particle interactions and interfacial interactions(such as surface tension and particle wetting),play a crucial *** literature,simulations of three-phase flows are sometimes performed by incorporating interface capturing methods(*** method)into the CFD-DEM coupling ***,it is practically impossible to perform large(industrial)scale simulation because of the high computational *** of the strategies often employed to reduce the computational cost in CFD-DEM is to upscale particle size,which is applied mainly to particle single-phase and fluid-solid two-phase *** present work is focused on the scaled-up particle model for gas-liquid-solid three-phase *** interaction forces between multiple phases are scaled using the general criteria derived from the continuum assumption of particulate flow.A colour function based interface-capturing method with improved interface smoothness is developed,and the diffusion based coarse graining is employed to ensure sufficient space resolution in CFD even when particle size is *** is shown that the model developed is capable of predicting the both particles and fluid behaviour in the original system.

关键词： CFD-DEM Three-phase flow Scaled-up particle Surface tension and wetting

Feeding Habits of the Copper Shark, Carcharhinus brachyurus （Gunther, 1870） from Ain ei-Ghazala Lagoon, Eastern Libya during the Period from February till June 2013

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Journal of Life Sciences 2015年第8期9卷 347-355页

作者： Raft, Esam Mahmoud Khamis ei-Mor, Mohammad E1-Sayed ei-Sayed Marine biology Branch Zoology Department Faculty of Science Omar A I-Mukhtar University El-Bieda P. O Box 919 Libya Department of Marine Science Faculty of Science Suez Canal University Ismailia 41611 Egypt

The feeding habits of 140 specimens of Carcharhinus brachyurus （Fam. Carcharhinidae） inhabiting Ain-ei-Ghazala lagoon on the Mediterranean Sea, eastern Libya were studied monthly from February to June 2013. The annual diet composition, monthly variations in the diet composition, the variations of diet with length and the intensity of feeding were studied. Carcharhinus brachyurus feed on a wide variety of prey types： Pelagic bony fishes （54.5%）, benthic bony fishes （36.4%）, Cephalopods （6.8%）, Cartilaginous fishes （1.7%） and Fish parts （0.6%）. The Pelagic bony fishes and benthic bony fishes were the major food items during the study period in question, and they were found in all length groups. According to the results that were gleamed from this study, when the size of the sharks increased, the proportion of pelagic bony fishes within the sharks＇ stomachs grew in size, while the benthic bony fishes and Cephalopods decreased in size. The feeding intensity was quite high during the winter, spring and summer, this study is the first to study the Elasmobranchs in Libya, and it will be good base to study another species, specifically.

关键词： Feeding habits Carcharhinus brachyurus Ain-ei-Ghazala lagoon eastern coast Mediterranean Sea Libya.

A mathematical model for preventing HIV virus from proliferating inside CD4 T brownian cell using Gaussian jump nanorobot

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International Journal of Biomathematics 2019年第7期12卷 71-94页

作者： Mohamed Abd Allah ei-Hadidy Alaa A.Alzulaibani Mathematics and Statistics Department College of Science Taibah UniversityYanbuKingdom of Saudi Arabia Mathematics Department Faculty of Science Tanta UniversityTantaEgypt

We present a statistical distribution of a nanorobot motion inside the *** distribution is like the distribution of A and B particles in continuous time random walk scheme inside the fAuid reactive anomalous transport with stochastic waiting time depending on the Gaussian distribution and a Gaussian jump length which is detailed in Zhang and Li[***,Published Online with doi:10.1007/s10955-018-2185-8,2018].Rather than estimating the length parameter of the jumping distance of the nanorobot,we normalize the Probability Density Function(PDF)and present some reliability properties for this *** addition,we discuss the truncated version of this distribution and its statistical properties,and estimate its length *** use the estimated distance to study the conditions that give a finite expected value of the first meeting time between this nanorobot in the case of nonlinear flow with independent d-dimensional Gaussian jumps and an independent d-dimensional CD4 T Brownian cell in the blood(d-space)to prevent the HIV virus from proliferating within this cell.

关键词： Stochastic waiting time CD4 T Brownian cell nanorobot distribution uni-formly integrable functions

Effects of Cadmium on Polar Lipid Composition and Unsaturation in Maize(Zea mays) in Hydroponic Culture

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Journal of Integrative Plant Biology 2007年第12期49卷 1693-1702页

作者： Radhouane Chaffai Tinni Nouhou Seybou Brahim Marzouk Ezzedine ei Ferjani Laboratoire de Bio-Physiologie Cellulaires Vegetales Faculte des Sciences de Bizerte 7021 Zarzouna-BizerteTunisie Laboratoire ERTAC Physiologie et Genetique Vegetales 63177 AubiereClermont FerrandFrance Laboratoire d'Adaptation et d'Amelioration des Plantes Institut National de la Recherche Scientifique et Technique(INRST)BP 95-2050 Hammam-LifTunisie

This study aimed to evaluate the effect of Cd exposure （100 μmol/L） on polar lipid composition, and to examine the level of fatty acid unsaturation in maize （Zea mays L.）. In roots, the level of 16：0 and monounsaturated fatty acids （16：1 ＋ 18：1） decreased in phosphatidylcholine （PC） and phosphatidylethanolamine （PE）. In contrast, the proportion of unsaturated 18-C fatty acid species showed an opposite response to Cd. The content, on the other hand, of PC, PE, digalactosyldiacylglycerol （DGDG）, and steryl lipids increased in roots （2.9-, 1.6-, 5.3-, and 1.7-fold increase, respectively）. These results suggest that a more unsaturated fatty acid composition than found in control plants with a concomitant increase in polar lipids may favor seedling growth during Cd exposure. However, the observed increase in the steryl lipid （SL）： phospholipid （PL） ratio （twofold）, the decrease in monogalactosyldiacylglycerol （MGDG）： DGDG ratio, as well as the induction of lipid peroxidation in roots may represent symptoms of membrane injury. In shoots, the unsaturation level was markedly decreased in PC and phosphatidylglycerol （PG） after Cd exposure, but showed a significant increase in sulfoquinovosyldiacylglycerol （SQDG）, MGDG and DGDG. The content of PG and MGDG was decreased by about 65%, while PC accumulated to higher levels （4.4-fold increase）. Taken together, these changes in the polar lipid unsaturation and composition are likely to be due to alterations in the glycerolipid pathway. These results also support the idea that the increase in overall unsaturation plays some role in enabling the plant to withstand the metal exposure.

关键词： cadmium fatty acids heavy metal stress lipid peroxidation polar lipids unsaturation level Zea mays.

FeO-rich silicates and Ca, Al-rich inclusions in Qingzhen andYamato 691 (EH3) meteorites: Evidence for migration of mass in the solar nebula

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Chinese Science Bulletin 2002年第2期47卷 150-153页

作者： LIN Yangting OUYANG Ziyuan A.ei Goresy Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China Max-Planck-Institut fur Chemie

The Qingzhen and Yamato 691 (EH3) enstatite chondrites, which formed under extremely reducing condi-tions, are studied using the scanning electron microscope and electron probe microanalyzer. Both meteorites contain FeO-rich silicates and minor Ca, Al-rich inclusions. Most FeO-rich silicates are Ca-poor pyroxenes and occur as frag-ments in matrix. A few grains of FeO-rich silicates were found in chondrules, and FeO-rich olivine is rare. In Qingzhen, FeO-rich silicates commonly contain abundant dust-like Ni-poor metals, which probably formed through reduction of FeO. In contrast, only a few fragments of FeO-rich silicates in Yamato 691 enclose dust-like metals. This difference is consistent with a more reducing condition of Qingzhen than Yamato 691. Ca, Al-rich inclusions have similar modal compositions and mineral chemistry as their counterparts in carbonaceous chondrites. We suggest that (1) the FeO-rich silicates probably formed in oxidized regions of the solar nebula, and then moved into the

关键词： solar nebula meteorite enstatite chondrite reduction migration.

Characteristics in naturally and experimentally shocked chondrites: A clue to P-T conditions of impacted asteroids

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Science China Earth Sciences 2000年第5期43卷 480-486页

作者：谢先德陈鸣戴诚达 A.ei Goresy Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Max-Planck-Institute fur Chemie Mainz 55128 Germany

The aim of this study is to compare the experimentally shock-induced features with those in naturally shocked chondrites and to test the feasibility of experimentally calibrating naturally induced features in shocked H- and L-chondrites. Samples of the Jilin chondrite (H5) were experimentally shock-loaded at the following peak pressures: 12, 27, 39, 53, 78, 83, 93 and 133 GPa respectively. Chondritic melts were first obtained at P>78 GPa and more than 60% melting was achieved at P^133 GPa. No high-pressure phases were observed in any of the shocked samples, neither in the deformed nor in the molten regions. Textural relations and mineral assemblages of the shocked samples are comparable to those encountered in the heavily shocked H-chondrite Yanzhuang but differ considerably from those found in heavily shocked L6 chondrites. Shock melt veins in L6 chondrites contain high-pressure polymorphs of olivine and pyroxene and high pressure liquidus phases. Scaling from shock experiments on millimeter-sized samples to natural shock features on kilometer-sized asteroids poses considerable problems in quantifying the P-T conditions during natural shock events on asteroids.

关键词： chondrite experiment shock characteristics asteroid P-T condition.