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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 52-66页

作者： Tharwat Mahmoud el-sherbini Physics Department Faculty of Science Cairo University Cairo Egypt

A model for a dual universe is proposed, based on the assumption that simultaneously with our universe an anti-matter counterpart was initiated immediately following the Big Bang. At the heart of the model is a primordial anti-particle that differentiates itself from its counterpart, a previously hypothesized s-particle responsible for the formation of our own universe, through its course of rotation. The angular rotation of the anti-particle, in accordance with space-time rotation, together with the counter rotation of the s-particle, resulted in a time difference in the formation processes of both universes and consequently led to a large distance between the spatial locations occupied by our universe and its dual counterpart in the same space-time continuum. The existence of this anti-matter universe might solve the present mystery of matter anti-matter asymmetry and thus explain why hardly any free anti-matter can be observed in our universe. Moreover, the model implicates the possibility of the presence of a repulsive gravitational force exerted by the clusters of anti-particles in the anti-matter universe upon our universe. The repulsive gravitational force from the clusters of antiparticles in the dual universe as a whole upon our universe is completely different from the electrostatic repulsive force between similarly charged particles. It is also different from that due to possible gravitational or anti-gravitational interaction between individual matter and antimatter or particle and its antiparticle that might violate the CPT invariance, the theory of general relativity or the law of energy conservation. It is rather, a kind of negative gravity that affects our universe as a whole, due to the opposite course of rotation of the dual anti-universe relative to ours. The effect of this opposite rotation of the dual universe can cause anti-gravitational waves that penetrate our universe interacting with the space-time mesh around the galaxies in our universe a

关键词： Cosmology Antimatter High Energy Astrophysics Particle Physics

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Combining ability of Egyptian cotton(Gossypium barbadense L.)reveals genetic potential for improved yield and fiber quality

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Journal of Cotton Research 2024年第2期7卷 109-122页

作者： abdelghany Ahmed M. el-Banna Aly A.A. lamlom sobhi F el-sorady Gawhara A. s.lama Ehab A.A. Ren Honglei shaibu abdulwahab s. Yehia Waleed M.B. Crop science Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt Plant Production Department Faculty of Agriculture Saba BashaAlexandria UniversityAlexandria 21531Egypt Agricultural Botany Department Faculty of Agriculture Saba BashaAlexandria UniversityAlexandria 21531Egypt Heilongjiang Academy of Agricultural sciences Soybean Research InstituteHarbin 150086China Department of Agronomy Bayero University KanoKano 700001Nigeria Cotton Breeding Department Cotton Research InstituteAgriculture Research CenterGizaEgypt

Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber *** this study,the general combining ability(GCA)and specific combining ability(sCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were *** The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied ***,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality *** F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality *** analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton *** component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic *** This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton.

关键词： Gossypium barbadense L. Combining ability seed cotton yield Fiber quality Cluster analysis Path analysis

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Physical studies of some Hydrazinobenzoic Acid Complexes

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Journal of Materials science & Technology 2005年第1期21卷 140-144页

作者： M.G.abd el Wahed s.abd el Wanees M.el Gamel s.abd el Haleem Faculty of science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig Egypt

The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (Ⅱ), Cu (Ⅱ), Zn (Ⅱ), Cd (Ⅱ), and Hg (Ⅱ) were determined potentiometricaIly at different temperatures. The thermodynamic parameters, △G0, △H0, and △s0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are M:L and M:2L. The structure of the prepared solid complexes was characterized using IR, 1H NMR, 13C NMR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

关键词： Potentiometric titration stability constants Thermodynamic parameters structure of metal complexes

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Energy Design and Optimization of Greenhouse by Natural Convection

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1903-1913页

作者： H.Benzzine H.Labrim Aouatif saad Y.Achour D.Zejli R.el Bouayadi Advanced systems Engineering Laboratory(Aselab) National School of Applied SciencesIbn Tofail UniversityKenitraMorocco

This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural *** primary objective of this study is to evaluate various ventilation strategies to enhance energy efficiency and optimize crop production in agricultural *** advanced numerical simulation tools,the study conducts a comprehensive assessment of natural ventilation’s effectiveness under real-world *** results underscore the crucial role of the stack effect and strategic window positioning in greenhouse cooling,providing valuable insights for greenhouse *** findings shed light on the significant benefits of optimized ventilation and also offer practical implications for improving greenhouse design,ensuring sustainable and efficient agricultural *** study demonstrated energy savings in cooling from November to April,with a maximum saving of 680 kWh in March,indicating the effectiveness of strategically positioning windows to leverage the stack *** approach enhances plant growth and reduces the need for costly cooling systems,thereby improving overall energy efficiency and lowering operational expenses.

关键词： Energy greenhouse cooling natural ventilation simulation temperature

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Evaluating Ignition and Combustion Performance with Al-Metal- Organic Frameworks and Nano-Aluminum in HTPB Fuel

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火炸药学报 2024年第5期47卷 413-421,I0003页

作者： sri Nithya Mahottamananda Yash Pal Yarravarapu sai sriram subha s Djalal Trache Department of Aerospace Engineering B S Abdur Rahman CrescentInstitute of Science and TechnologyChennai-600048India school of Aeronautical science Hindustan Institute of Technologyand ScienceChennai-603103India Energetic Materials Laboratory(EMLab) Teaching and ResearchUnit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria

Incorporating aluminum metal-organic frameworks(Al-MOFs)as energetic additives for solid fuels presents a promising avenue for enhancing combustion *** study explores the potential benefits of Al-MOF(MIL-53(Al))energetic additive on the combustion performance of hydroxyl-terminated polybutadiene(HTPB)*** HTPB-MOF fuel samples were manufactured using the vacuum-casting technique,followed by a comprehensive evaluation of their ignition and combustion properties using an opposed flow burner(OFB)setup utilizing gaseous oxygen as an *** gauge the effectiveness of Al-MOFs as fuel additives,their impact is compared with that of nano-aluminum(nAl),another traditional additive in HTPB *** results indicate that the addition of 15%(mass fraction)nAl into HTPB resulted in the shortest ignition delay time(136 ms),demonstrating improved ignition performance compared to pure HTPB(273 ms).The incorporation of Al-MOF in HTPB also reduced ignition delay times to 227 ms and 189 ms,***,under high oxidizer mass flux conditions(79—81 kg/(m^(2)s)),HTPB fuel with 15%nAl exhibited a substantial 83.2%increase in regression rate compared to the baseline HTPB fuel,highlighting the positive influence of nAl on combustion *** contrast,HTPB-MOF with a 15%Al-MOF additive showed a 32.7%increase in regression rate compared to pure *** results suggest that HTPB-nAl outperforms HTPB-MOF in terms of regression rates,indicating a more vigorous and rapid burning behavior.

关键词： ignition combustion enhancement MOF HTPB regression rate

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Planning Target Volume Margin in Linac-Based stereotactic Radiosurgery for Brain Metastases

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Journal of Cancer Therapy 2024年第7期15卷 265-272页

作者： Hany s. Attallah Radwa M. Hamed Khaled M. el-shahat Aliaa Mahmoud Mahmoud abdallah Ibraheem Haggag Emad Moustafa Adel Yassin Department of Radiation Oncology International Medical Center (IMC) Cairo Egypt Department of Radiation Oncology Armed Forces Medical Collogue (AFCM) Cairo Egypt Department of Medical Physics Al Azhar University Cairo Egypt Department of Medical Physics International Medical Center (IMC) Cairo Egypt Department of Medical Physics Department of Clinical Oncology Faculty of Medicine Zagazig University Zagazig Egypt

Background: The treatment of brain metastases with radiotherapy has shifted to the use of stereotactic Radio-surgery (sRs). The technical issue of expanding the treatment volume around the Gross Tumor Volume (GTV) is a current debate. Radiotherapy centers use variable GTV-PTV margins, ranging from one to 2 mm. Material and Methods: We performed a dosimetric comparison in plans of twenty patients using three margins: PTV zero, PTV1, and PTV2. We also developed imaginary Peel volumes. These volumes are described as follows: Peel1 = PTV1 − GTV, Peel2 = PTV2 − GTV. Results: Our results showed that the mean PTV volume differed significantly across the different margins (p = 0.000). The V12 of the brain significantly varied as a function of PTV margin (p = 0.000). The target coverage and plan quality indices were not significantly different. The Peel volume dosimetric analysis showed that the mean dose was significantly higher in the nearby normal brain tissue: Peel1 (p = 0.022) and Peel 2 (p = 0.013). Conclusion: According to our dosimetric analysis, expanding the GTV into a PTV by 1 mm margin is more convenient than 2 mm.

关键词： sRs Brain Metastases PTV

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study of Hygrothermal Behavior of Bio-sourced Material Treated Ecologically for Improving Thermal Performance of Buildings

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Journal of Renewable Materials 2024年第5期12卷 1007-1027页

作者： soumia Mounir Miloudia slaoui Youssef Maaloufa Fatima Zohra el Wardi Yakubu Aminu Dodo sara Ibn-elhaj abdelhamid Khabbazi National school of Architecture Agadir New Complex Ibn Zohr AgadirHay dakhla80000Morocco EMDD CERNE2DUniversity Mohammed V in RabatEst SaléSaléMedinaMorocco Physics Department LPMAT LaboratoryFaculty of Sciences Ain ChockHassan II UniversityCasablancaMorocco Architectural Engineering Department College of Engineering Najran UniversityNajran66426Saudi Arabia The Centre of scientific and Engineering Research Najran UniversityNajranSaudi Arabia

Creating sustainable cities is the only way to live in a clean environment,and this problem can be solved by using bio-sourced and recycled *** this purpose,the authors contribute to the valuation of sheep wool waste as an eco-friendly material to be used in *** paper investigates the thermal,hygrothermal,and biological aspects of sheep wool by testing a traditional *** biological method of aerobic mesophilicﬂora has been *** X was used to determine the chemical composition of the materials ***,thermal characterization has been *** thermal conductivity is above 0.046(W·m^(-1)·K^(-1))and the thermal diffusivity is 1.56.10^(-6) m^(2)·s^(-1).Besides,the energy efﬁciency of using sheep wool in buildings was ***,its humidity behavior was evaluated in different aspects in both winter and *** of biological analyses show the efﬁciency of the treatment by removing the majority of the microorgan-isms:the value of yeast and mildew was reduced from 38.10^(2) to 2.10^(2)(UFC·g^(-1)).In addition to that,sheep wool permits obtaining a low thermal transmittance on the scale of the walls and low cooling needs on the scale of the building with a gain of 45%and 52%,respectively.

关键词： sustainability sheep wool biological treatment hygrothermal wool behavior hot wire method

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Effect of Conductive Fillers on the Cyclic stress-strain and Nano-scale Free Volume Properties of silicone Rubber

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Chinese Journal of Polymer science 2014年第5期32卷 558-567页

作者： M.H.abd-el s.lam s.el-Gamal M.Mohsen D.M.abd el-Maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDMs） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALs）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DsC）. Tm and the degree of crystallinity （χc） of PDMs composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDMs loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALs. Moreover, the hysteresis in PDMs-CB composites was more pronounced than in PDMs-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDMs composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume si-rubber Composite Cyclic mechanical properties.

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Analysis of cerium substitution in Co-sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： Laura Khudaysh Inas A.Ahmed syeda Rabia Ejaz sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.el-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in solid state Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

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Physio-biochemical and nutrient constituents of peanut plants under bentazone herbicide for broad-leaved weed control and water regimes in dry land areas

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Journal of Arid Land 2020年第4期12卷 630-639页

作者： Hani s sAUDY Ibrahim M el–METWALLY Goma A abd el–sAMAD Agronomy Department Faculty of AgricultureAin Shams University68–Hadayek Shoubra 11241CairoEgypt Botany Departments National Research CentreEl–Behos St.Dokki 12622CairoEgypt

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels(I_(50), I_(75) and I_(100), representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices(bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I_(50) significantly equaled with its counterpart under I_(75) or I_(100). Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I_(100) in both growing seasons as well as hoeing twice under I_(75) in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I_(75) recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I_(50), I_(75) and I_(100), respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

关键词： biochemical traits drought nutritional status peanut productivity weed growth

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