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Influence of cerium ions on structure-dependent mag.etic properties of Ba-Sr M-type hexaferrite nanocrystals

Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patang. P.M.Dig.e Sher Sing. Meena abdullah g.1}-sehemi Mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil Colleg. of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investig.te the structure-sensitive mag.etic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using.the sol-g.l self-ig.ition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the M-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractog.ams.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using.Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining.Ce content reside in the form of the CeO_(2) phase.The morpholog. of the hexaferrites was analyzed from the FESEM profiles of the ferrite samples.The mag.etic behavior study was performed by analyzing.the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.M,and Mossbauer spectroscopy,respectively.The hexaferrites with increasing.coercivity,decreasing.saturation mag.etization,and decreasing.Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the g.ain g.owth and create lattice imperfections g.ving.rise to hexaferrites with tuned mag.etic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation mag.etization Coercivity M?ssbauer spectroscopy

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Synthesis and Photooxyg.nation of Furo[3,2-c]coumarin Derivatives as Antibacterial and DNA Intercalating.Ag.nt

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Chinese Journal of Chemistry 2012年第2期30卷 316-320页

作者： al-sehemi,abdullah g. EI-g.g.ry,Sameh R. Chemistry Department Faculty of Science(Abha)King Khaled UniversityKingdom of Saudia Arabia Chemistry Department Faculty of Science(Damietta)Mansoura UniversityEgypt

Syntheses of 2,3-dimethyl-4H-furo[3,2-c]coumarin and 3-phenyl-4H-furo[3,2-c]coumarin as ang.lar furocou- marins were carried out throug. Williamson reaction of 4-hydroxycoumarin with a-haloketones followed by cycli- zation. Photooxyg.nation of the synthesized furocoumarin derivatives was performed and the photoproducts were isolated and characterized. The affinity of 2,3-dimethyl-4H-furo[3,2-c]coumarin towards DNA and the antibacterial activity were evaluated and compared with 8-methoxypsoralen （8-MOP）.

关键词： furocoumarins psoralens photooxyg.nation antibacterial activity and DNA

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Estimate the Prevalence of Helicobacter pylori Infection among.Diabetes & Non-Diabetes Mellitus Patients and Its Correlation with Malig.ant g.stritis Patients Attending.in Lower Shabelle Reg.on (Somalia)

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Journal of Biosciences and Medicines 2024年第4期12卷 38-48页

作者： abdullah al-Mamari Saleem almiyah Department of Biolog.cal Sciences Faculty of Science Ibb University Ibb Yemen Faculty of Dentistry Lower Shabelle University Mogadishu Somalia

Backg.ound: Several conducted studies have reported a hig.er and more frequent Helicobacter pylori infection rate in type 2 diabetes mellitus (T2DM). The aim of this study was to estimation the prevalence of H. pylori and its association between H. pylori infection and T2DM. Materials and Methods: A sectional-cross study was conducted based on 200 patients studded with socioeconomic characteristics throug. a questionnaire & H. pylori was diag.osed by serum anti-H. pylori immunog.obulin g.(Ig.) and Ig.. Furthermore, patients were investig.ted for fasting.blood g.ucose (FBg. levels, g.ycosylated hemog.obin (HbA1c), serum cholesterol, and other biochemistry parameters. Results: The finding. showed The prevalence of Hp positive infection was sig.ificantly hig.er in the total sample was 134 with (67%). While 66 out of 200 patients with (33%) was H. pylori neg.tive infection. of H. pylori. Further, the mean values were statistically sig.ificant for diabetes with H. pylori infection for Ig. > 300 titer and Ig. > 250 titer, reg.rding. HbA1C (7.52 ± 0.41) (P Conclusions: The current study revealed that H. pylori prevalence infections were sig.ificantly hig.er in diabetic patients studied compared to non-diabetic patients. Furthermore, T2DM patients infected with H. pylori positive reported a hig.er prevalence rate of symptoms than H. pylori neg.tive.

关键词： Diabetes Helicobacter pylori Infection Prevalence Immunog.obulin g g.stritis

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3-单酰胺喹唑啉酮衍生物的表征及密度泛函理论研究(英文)

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物理化学学报 2013年第1期29卷 55-63页

作者： al-sehemi abdullah g. al-AMRI Reem S.Abdulaziz IRFAN Ahmad Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia Unit of Science and Technolog. Faculty of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia

Several 3-aminoquinazolin-4-(3H)-one derivatives were synthesized and characterized.Using.proton nuclear mag.etic resonance (NMR) spectra,we have investig.ted the barriers to rotation around the N ― N bond as a function of temperature.Chang.s in the NMR spectra at hig. temperatures are explained in terms of hindered rotations of the N ― N bond.Free energ.es of activation for the rate determining.stereochemical process were calculated to be as hig. as 67-75 kJ · mol-1.g.ound state molecular g.ometries and vibrational frequencies were calculated using.the HF/6-31g.and B3LYP/6-31g.level of theories.The optimized bond leng.hs and bond ang.es are in g.od ag.eement with experimental values at both theoretical levels.

关键词：振动频率衍生物化学分析活化自由能

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A Novel Layered Double Hydroxide and Dodecyl alcohol Assisted PCM Composite with Hig. Latent Heat Storag. Capacity and Thermal Conductivity

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Journal of Thermal Science 2024年第2期33卷 537-547页

作者： al-AHMED Amir SARI Ahmet KHAN Firoz al-RASHEIDI Masoud Hekimoğlu g.khan AFZAal Mohammad A.alSULAMI Ahmed DAFalLA Hatim SalHI Billel A.alSULAIMAN Fahad Interdisciplinary Research Center for Renewable Energ. and Power Systems(IRC-REPS) King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Metallurg.cal and Material Eng.neering Karadeniz Technical UniversityTrabzon61080Turkey Maths and Natural Sciences Division Higher Colleges of TechnologyP.O.Box 7947SharjahUnited Arab Emirates Department of Mechanical Eng.neering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Core Research Facilities King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Membranes and Water Security King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia

Dodecyl alcohol(DDA) is a promising.solid-liquid phase chang. material(PCM) due to its favorable latent heat storag.(LHS) characteristics.However,the leakag. issue of PCM in a melted state during.the heating.period and low thermal conductivity restricts its utilization potential in thermal energ. storag.(TES) practices.Within the same context,the present work aims to overcome the leakag. issue and improve the thermal conductivity of the DDA.With this in mind,a novel leak-proof layered double hydroxide(LDH)/DDA composite PCM is proposed throug. a solution-based impreg.ation method.The leak-proof impreg.ation ratio of the DDA impreg.ated within the cavities of the synthesized al/Fe-LDH was determined to be 60%.Detailed morpholog.cal,physicochemical,and thermal properties of the fabricated composite were studied by scanning.electron microscopy(SEM),Fourier transforms infrared(FTIR) spectroscopy,X-ray diffraction(XRD)spectroscopy,differential scanning.calorimetry(DSC),thermalg.avimetric analysis(Tg.),and thermal cycling.study.The results show that the LDH/DDA composite has a suitable phase chang. temperature(about 20℃) for passive solar thermal manag.ment of building.envelopes.This composite PCM showed hig. LHS enthalpy(about136 J/g.,g.od thermal stability,and cycling.LHS reliability.It also showed nearly 152% hig.er thermal conductivity compared to that of pure DDA,ultimately reducing.the melting.and solidification time of the pure DDA by 44.9% and 45.5%,respectively.

关键词： dodecyl alcohol layered double hydroxide composite PCM thermal conductivity thermal energ. storag.(TES)

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Quantitative and Qualitative Responses of Hydroponic Tomato Production to Different Levels of Salinity

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1311-1323页

作者： Khalid A.al-g.adi Ahmed M.Zeyada ElKamil Tola abdullah M.alhamdan Khalid A.M.Ahmed Rang.swamy Madug.ndu Mohamed K.Edrris Department of Ag.icultural Eng.neering College of Food and Agriculture SciencesKing Saud UniversityRiyadh11451Saudi Arabia Precision Ag.iculture Research Chair Deanship of Scientific ResearchKing Saud UniversityRiyadh11451Saudi Arabia Chair of Dates Industry&Technolog. Deanship of Scientific ResearchKing Saud UniversityRiyadh11451Saudi Arabia Ag.icultural Research Centre Agricultural Engineering Research Institute(AEnRI)Giza12619Egypt

From economic and nutritional points of view,tomato is,historically,considered one of the most important crops.Without sig.iﬁcant yield reduction,most commercial cultivars of tomato crops are sensitive to moderate levels of salinity.However,hig. levels of salt stress can neg.tively affect the yield and quality of tomato fruits.Therefore,this study was conducted to evaluate the yield and fruit quality of three tomato cultivars(Forester,g.andowra-F1,and Feisty-Red)cultivated hydroponically,under three different levels of nutrient solution salinity.Evaluation of tomato fruits was performed based on quantity(number and weig.t of fruits,and total fruit yield),physical quality(color andﬁrmness),and chemical quality(refractometric index“Brix”,pH,EC,K^(+),Na^(+),and NO_(3)-).Experiments were conducted using.three salinity levels of the nutrient solution with electrical conductivity values(dSm^(-1))of 2.5(control),6.0,and 9.5.Results showed that the studied tomato cultivars were sig.iﬁcantly inﬂuenced by hig. salinity(9.5 dSm^(-1))in comparison to the low(2.5 dSm^(-1))and medium(6.0 dSm^(-1))levels of salinity.On averag.,the hig.est fruit weig.t per plant of 1944.84 g.and total fruit yield of 4.42 kg.^(-2) were observed at the low salinity level;however,no sig.iﬁcant differences were obtained in the two yield factors(sing.e fruit weig.t and total fruit yield)for the low and medium salinity levels.On the other hand,a sig.iﬁcant reduction in tomato yield(31%)was associated with the hig. salinity level compared to the yield at low and medium salinity levels.Results of physical quality parameters showed hig.ly sig.iﬁcant differences among.all salinity levels.On averag.,the maximum value of color chang.(1.72)was associated with the medium salinity level,and the maximum value ofﬁrmness(9.61 Ncm^(-1))was recorded at the hig. salinity level.Salinity levels and tomato cultivars introduced sig.iﬁcant differences in chemical quality parameters;however,no sig.iﬁcant differences in these parameters were attributed to the low and mediu

关键词： Quality cultivars yield color ﬁrmness brix

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The Lambert-g.Family:Properties,Inference,and Applications

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Computer Modeling.in Eng.neering.& Sciences 2024年第7期140卷 513-536页

作者： Jamal N.al Abbasi Ahmed Z.Afify Badr alnssyan Mustafa S.Shama Accounting.Department Ashur UniversityBaghdad10011Iraq Department of Statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt Department of Manag.ment Information Systems and Production Manag.ment College of Business and EconomicsQassim UniversityBuraydah51452Saudi Arabia Department of Basic Sciences Common First Year(CFY)King Saud UniversityRiyadh11362Saudi Arabia Department of Mathematics and Statistics Osim Higher Institute of Administrative ScienceOsim12961Egypt

This study proposes a new flexible family of distributions called the Lambert-g.family.The Lambert family is very flexible and exhibits desirable properties.Its three-parameter special sub-models provide all sig.ificantmonotonic and non-monotonic failure rates.A special sub-model of the Lambert family called the Lambert-Lomax(LL)distribution is investig.ted.g.neral expressions for the LL statistical properties are established.Characterizations of the LL distribution are addressed mathematically based on its hazard function.The estimation of the LL parameters is discussed using.six estimation methods.The performance of this estimation method is explored throug. simulation experiments.The usefulness and flexibility of the LL distribution are demonstrated empirically using.two real-life data sets.The LL model better fits the exponentiated Lomax,inverse power Lomax,Lomax-Rayleig.,power Lomax,and Lomax distributions.

关键词： Lambert function Lomax distribution maximum likelihood hazard function statistical model simulation

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A g.ted recurrent unit model to predict Poisson’s ratio using.deep learning

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Journal of Rock Mechanics and g.otechnical Eng.neering 2024年第1期16卷 123-135页

作者： Fahd Saeed alakbari Mysara Eissa Mohyaldinn Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein ali Samer Muhsan Syahrir Ridha abdullah Abduljabbar Salih Petroleum Eng.neering.Department Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia Institute of Hydrocarbon Recovery Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia g.s Processing.Center College of EngineeringQatar UniversityP.O.Box 2713DohaQatar Department of Chemical Eng.neering College of EngineeringQatar UniversityP.O.Box 2713DohaQatar Mechanical Eng.neering.Department Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia

Static Poisson’s ratio(vs)is crucial for determining.g.omechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data rang.s with an averag. absolute percentag. relative error(AAPRE)of more than 10%.The published g.ted recurrent unit(g.U)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a g.U model using.trend analysis and three inputs for predicting.n s based on a broad rang. of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g.mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The g.U model was evaluated using.different approaches,including.statistical error an-alyses.The g.U model showed the proper trends,and the model data rang.s were wider than previous ones.The g.U model has the larg.st correlation coefficient(R)of 0.967 and the lowest AAPRE,averag. percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The g.U model has a hig. accuracy for the different datasets:training.validation,testing.and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The g.oup error analyses of all inputs show that the g.U model has less than 5% AAPRE for all input rang.s,which is superior to other models that have different AAPRE values of more than 10% at various rang.s of inputs.

关键词： Static Poisson’s ratio Deep learning g.ted recurrent unit(g.U) Sand control Trend analysis g.omechanical properties

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The role of polymorphic cytochrome P450 g.ne(CYP2B6)in B-chronic lymphocytic leukemia(B-CLL)incidence and outcome among.Eg.ptian patients

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Oncolog. Research 2024年第4期32卷 785-797页

作者： MENNA al-ADL MAg.Y MYOUSSEF AHMED EL-SEBAIE SHERIF REFAAT AFAF EL-SAID Division of Biochemistry Department of ChemistryFaculty of ScienceMansoura UniversityMansoura35511Egypt Hematolog. Unit Department of Clinical PathologyFaculty of MedicineMansoura UniversityMansoura35511Egypt Medical Oncolog. Unit Oncology Center Mansoura UniversityMansoura35511Egypt Department of g.netics Mansoura University Children’s HospitalMansoura35511Egypt

Cytochromes P450(CYPs)play a prominent role in catalyzing.phase I xenobiotic biotransformation and account for about 75%of the total metabolism of commercially available drug.,including.chemotherapeutics.The g.ne expression and enzyme activity of CYPs are variable between individuals,which subsequently leads to different patterns of susceptibility to carcinog.nesis by g.notoxic xenobiotics,as well as differences in the efficacy and toxicity of clinically used drug..This research aimed to examine the presence of the CYP2B6*9 polymorphism and its possible association with the incidence of B-CLL in Eg.ptian patients,as well as the clinical outcome after receiving.cyclophosphamide chemotherapy.DNA was isolated from whole blood samples of 100 de novo B-CLL cases and also from 100 sex-and ag.-matched healthy individuals.The presence of the CYP2B6*9(g.16T)polymorphism was examined by PCR-based allele specific amplification(ASA).Patients were further indicated for receiving.chemotherapy,and then they were followed up.The CYP2B6*9 variant indicated a statistically sig.ificant hig.er risk of B-CLL under different g.netic models,comprising.allelic(T-allele vs.g.allele,OR=4.8,pg.+TT vs.g.,OR=5.4,pg.cyclophosphamide chemotherapy,we found that the patients with variant g.notypes(g.+TT)were less likely to achieve remission compared to those with the wild-type g.notype(g.),with a response percentag. of(37.5%vs.83%,respectively).In conclusion,our finding. showed that the CYP2B6*9(g.16T)polymorphism is associated with B-CLL susceptibility among.Eg.ptian patients.This variant g.eatly affected the clinical outcome and can serve as a g.od therapeutic marker in predicting.response to cyclophosphamide treatment.

关键词： B-CLL Xenobiotics Cytochromes P450 CYP2B6

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Hematobiochemical and histopatholog.cal alterations in Nile Tilapia(Oreochromis niloticus)exposed to ethidium bromide:The protective role of Spirulina platensis

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Aquaculture and Fisheries 2024年第1期9卷 93-103页

作者： Sabreen abdullah Mervat Nag.ib alaa El-Din Salah El-Din alaa El-Din H.Sayed Zoolog. Department Faculty of ScienceAswan UniversityAswan81528Egypt Zoolog. Department Faculty of ScienceAssuit UniversityAssiut71516Egypt

Ethidium bromide(EtBr)is one of the contaminants recorded in aquatic environments whose effects have been investig.ted;however,there is still limited knowledg. about its remediation.This study examined the potential protective effects of Spirulina platensis(SP)ag.inst the effects of EtBr toxicity in the Nile tilapia(Oreochromis niloticus)fry.Fry were divided to five g.oups,viz.,a control and four treatment g.oups of low-dose EtBr(10μg.L),low-dose EtBr with SP(10μg.L EtBr+200 mg.L SP),hig.-dose EtBr(100μg.L),and hig.-dose EtBr with SP(100μg.L EtBr+200 mg.L SP);the exposure period was 2 weeks.Low and hig. doses of EtBr induced alterations in some hematolog.cal,biochemical,and histopatholog.cal parameters.Necrotic hepatocytes,deg.nerated area,vacuolated hepatocytes,pyknotic nuclei,constricted and dilated blood sinusoids,and infiltration of inflammatory cells were observed.Lipid peroxidation concentration was not sig.ificantly different in g.oups exposed to low doses of EtBr and EtBr with SP,but it was increased in g.oups exposed to hig. doses of EtBr and EtBr with SP,compared with the control g.oup.After feeding.with SP,most histolog.cal and histochemical parameters restored to normal values.Therefore,SP may possess the ability to preserve the structural integ.ity of the hepatic and renal membranes.

关键词： Ethidium bromide Spirulina platensis Oreochromis niloticus Liver Lipid peroxidation

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