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Numerical simulation for symmetric diffraction patterns of 8-hydroxyquinolin-1-ium 4-aminobenzenesulfonate

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Optoelectronics Letters 2022年第5期18卷 283-287页

作者： A.Ghanem m.D.Zidan m.S.EL-Daher A.Allahham Higher Institute for Laser Research and Applications Damascus UniversiySyria Department of Physics AECP.O.Box 6091DamascusSyria

We reported the formation of diffraction ring patterns induced by transmitted Gaussian laser beam through 8-hydroxyquinolin-1-ium 4-aminobenzenesulfonate(8 HQABS) solution as absorbing medium. Theoretical model depending on the Fresnel-Kirchhoff diffraction(FKD) theory was used to generate diffraction rings with respect to the sample position. Analysis of the generated diffraction rings shows a reasonable agreement between the features of the experimental and numerical diffraction rings. Our results are considered to be useful to understand the way of propagation and interaction of laser beam with liquid absorbing medium.

关键词： benzene rings absorbing

Optimal Bandgap of Double Perovskite La-Substituted Bi2FeCrO6 for Solar Cells:an ab initio GGA+U Study

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Chinese Physics Letters 2017年第1期34卷 81-85页

作者： B.merabet H.Alamri m.Djermouni A.Zaoui S.Kacimi A.Boukortt m.Bejar Electrotechnics Department Faculty of TechnologyMustapha Stambouli UniversityMascara 29000Algeria Computational materials Physics Laboratory UDL-SBA 22000Algeria Physics Department-University College Umm Ai-Qura UniversityMakkahSaudi Arabia Centre Universitaire Ahmed Zabana Relizane 48000Algeria Elaboration Characterization Physico-mechanics of materials and metallurgical Lboratory ECP3m Faculty of Sciences and TechnologyAbdelhamid Ibn Badis University of MostaganemMostaganem 27000Algeria Laboratoire de Physique Appliquee Faculte des SciencesUniversite de SfaxSfax 3000Tunisie

The ab initio generalized gradient approximation (GGA)+U study of multiferroic (La Bi )2FeCrO6 in pnma structure and ferri-magnetic order, including Hubbard corrections ( eV) for transition metal/rare earth d-electrons with 20 atoms cell, shows optimum local magnetic moments of (Cr , Fe equal to (−2.56, 4.14) μB and an ideal spin-down band gap of 1.54 eV. Tuned-band gap La-substituted double oxide perovskites BFCO should exhibit enhanced visible-light absorption and carrier mobility, thus could be convenient light absorbers and then efficient alternatives to wide-gap chalcopyrite absorber-based solar cells failing to achieve highest power conversion efficiencies, and even compete with their metal-organic halide perovskites counterparts.

关键词： Cr La Optimal Bandgap of Double Perovskite La-Substituted Bi2FeCrO6 for Solar Cells:an ab initio GGA+U Study Fe Bi GGA

Distribution and characterization of C_(31) sterane from cretaceous sediments and oils,Songliao Basin,China

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Chinese Science Bulletin 1999年第6期44卷 560-563页

作者： J. m. moldowan Department of Geological and Environmental Science Stanford University

Relatively high abundance of C31 steranes has been identified from cretaceous source rocks and crude oils in the Songliao Basin, China. C31 steranes which occur as ten isomers were tentatively identified as 4, 22, 23, 24-tetrametyhlcholestane based on their retention time and mass *** bear a lower thermal stability and occur as important components in the immature oils of Chaochang region because they have three-methyl groups in their side chain. The relatively high abundance of C31 steranes in the samples can indicate the source input of some special algae in the brackish and saline environment. Therefore they can be used as very useful biomarkers for organic facies analysis and oil correlation. Their biological source perhaps related to the dinoflagellate such as G. foliaceum and P. foliaceum. The gorgostanol are considered as possible precursors for the putative C314methyl sterane which formed in the stage of diagenesis.

关键词： C31 sterane ancient environment algae oil correlation.

A new design approach for the established flow region of vertical,dilute-phase pneumatic conveyors

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Particuology 2022年第7期20卷 10-20页

作者： John m.Wheeldon Jan Baeyens Shuo Li Yimin Deng European Powder and Process Technology Longfellow DriveKetteringUnited Kingdom KU Leuven Department of Chemical EngineeringProcess and Environmental Technology LabJ.De Nayerlaan 52860 Sint-Katelijne-WaverBelgium Beijing University of Chemical Technology Beijing Advanced Centre of Smart Matter Science and EngineeringBeijingChina

An analysis has been completed for a comprehensive set of vertical,dilute-phase pneumatic conveying pressure drop data from an investigation by *** data were collected in the established flow region for eight different materials conveyed in 0.05-,0.10-,0.20-m internal diameter,20-m tall steel *** velocities derived from the pressure drop data were used to develop an equation of motion that includes terms for pipe diameter,terminal velocity,coefficient of restitution,and particle *** best data fit was achieved using the actual gas density and the actual gas velocity adjusted for *** the terminal velocity for voidage,an approach recommended by many investigators,did not improve the fit for reasons identified by the present *** the equation of motion,particle velocities were predicted and used to calculate total pressure drops that are within±15%of the measured *** calculated values also produce the characteristic trough-shaped total pressure drop curves allowing the minimum pressure drop gas velocity to be determined without recourse to a separate correlation.A comparison with other studies using shorter risers indicates that data from these studies likely include acceleration effects.A separate study will investigate this observation further.

关键词： Dilute-phase Vertical Pneumatic conveying Design equations Pressure drops

Evaluation of antihyperglycemic activity of methanolic Tecomaria capensis Thunb.(Bignoniaceae) leaves extract in alloxan induced hyperglycemic rats

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Asian Pacific Journal of Tropical medicine 2012年第12期5卷 945-948页

作者： Neeraj Kumar Saini Singhal m Department of Pharmacology School of Pharmaceutical SciencesJaipur National University

Objective:To evaluate the antihyperglycemic activity of Tecomaria aipensis(***) Thunb. (Bignoniaceae) methanolic leaves extract(TCLE) using blood glucose level in normal fasted rats, glucose tolerance test and alloxan induced hyperglycemia ***:TCLE(100,300, 1 000 and 2 000 mg/kg body wt.) was given to rats orally to observe acute toxicity,and observed for 14 *** 200 and 400 mg/kg,and glibenclamide 0.6 mg/kg were given orally in all models. Results:Results demonstrated that the no mortality was reported even after 14 *** indicates that the methanol extract is safe up to a single dose of 2 000 mg/kg body ***(200 and 400 mg/kg p.o.) exhibited remarkable blood glucose lowering effect in blood glucose level in normal fasted rats,glucose tolerance and alloxan induced hyperglycemia *** and triglyceride also decreased in alloxan induced hyperglycemia ***:The results of this study exhibites that methanol extract of *** possesses antihypergycemic activity and it may prove to be effective for the treatment of hyperglycemia.

关键词： Antidiabatic Diabeties Alloxan Oral glucose tolerance

Anticancer property of sediment actinomycetes against mCF-7 and mDA-mB-231 cell lines

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Asian Pacific Journal of Tropical Biomedicine 2012年第2期2卷 92-96页

作者： Ravikumar S Fredimoses m Gnanadesigan m School of marine Sciences Department of Oceanography and Coastal Area StudiesAlagappa UniversityThondi CampusThondi-623 409Ramanathapuram District Department of Biotechnology K.S.Rangasamy College of Arts & ScienceThiruchengodu- 637209Namakkal District

ObjectiveTo investigate the anticancer property of marine sediment actinomycetes against two different breast cancer cell *** vitro anticancer activity was carried out against breast (mCF-7 and mDA-mB-231) cancer cell lines. Partial sequences of the 16s rRNA gene, phylogenetic tree construction, multiple sequence analysis and secondary structure analysis were also carried out with the actinomycetes *** the selected five actinomycete isolates, ACT01 and ACT02 showed the IC50 value with (10.13±0.92) and (22.34±5.82) μg/mL concentrations, respectively for mCF-7 cell line at 48 h, but ACT01 showed the minimum (18.54±2.49 μg/mL) level of IC50 value with mDA-mB-231 cell line. Further, the 16s rRNA partial sequences of ACT01, ACT02, ACT03, ACT04 and ACT05 isolates were also deposited in NCBI data bank with the accession numbers of GQ478246, GQ478247, GQ478248, GQ478249 and GQ478250, respectively. The phylogenetic tree analysis showed that, the isolates of ACT02 and ACT03 were represented in group I and III, respectively, but ACT01 and ACT02 were represented in group II. The multiple sequence alignment of the actinomycete isolates showed that, the maximum identical conserved regions were identified with the nucleotide regions of 125 to 221st base pairs, 65 to 119th base pairs and 55, 48 and 31st base pairs. Secondary structure prediction of the 16s rRNA showed that, the maximum free energy was consumed with ACT03 isolate (-45.4 kkal/mol) and the minimum free energy was consumed with ACT04 isolate (?7.6 kkal/mol).ConclusionsThe actinomycete isolates of ACT01 and ACT02 (GQ478246 and GQ478247) which are isolated from sediment sample can be further used as anticancer agents against breast cancer cell lines.

关键词： Actinomycetes Breast cancer mCF–7 mDA–mB–231 Phylogenetic tree Anticancer property multiple sequence analysis Secondary structure analysis Sediment Anticaner agent Cell line

Sequence stratigraphic evaluation for the Abu madi Formation,Abu madi/El Qar'a/Khilala gas fields,onshore Nile Delta,Egypt

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Petroleum Research 2023年第4期8卷 514-523页

作者： Farouk I.metwalli Amir Ismail m.S.metwally Ibrahim m.El Shafei Geology Department Faculty of ScienceHelwan UniversityCairoEgypt Desert Research Center CairoEgypt Petrobel Oil Company CairoEgypt

The present study aims to integrate a large set of geological and geophysical data into a comprehensive model describing the depositional features of the Abu madi/El Qar'a/Khilala gas *** model is based on the sequence stratigraphic framework of the Abu madi Formation defined using cores,well logs,and time-migrated seismic *** trace attribute sections and relative acoustic impedance sections are also used.A possible depositional pattern for the main Level Ill is established,based on the lithological and petrophysical information derived from the seismic data *** Abu madi For-mation can be regarded as a depositional sequence recording the progressive drowning of the incised *** sequence is bounded at the base by an erosional unconformity,created by a drop in the level of the Late messinian Sea,and at the top by a drowning unconformity related to the Early Pliocene *** bottom of Level II divides the Abu madi sequence into two smaller *** both sequences,gas-bearing traps can be found in the Lowstand Systems Tracts,represented by the fluvial Level Ill and fluvial-deltaic Level Il,respectively.

关键词： Abu madi gas field El Qar'a area Khilala area Sequence stratigraphy analysis Onshore Nile Delta Abu madi Formation

marsh persistence under sea-level rise is controlled by multiple,geologically variable stressors

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Ecosystem Health and Sustainability 2017年第10期3卷 22-38页

作者： m.mitchell J.Herman D.m.Bilkovic C.Hershner Virginia Institute of marine Science College of William&MaryGloucester PointVAUSA

Introduction:marshes contribute to habitat and water quality in estuaries and coastal *** importance to continued ecosystem functioning has led to concerns about their ***:Concurrent with sea-level rise,marshes are eroding and appear to be disappearing through ponding in their interior;in addition,in many places,they are being replaced with shoreline stabilization *** examined the changes in marsh extent over the past 40 years within a subestuary of Chesapeake Bay,the largest estuary in the United States,to better understand the effects of sea-level rise and human pressure on marsh ***:Approximately 30 years ago,an inventory of York River estuary marshes documented the historic extent of *** were resurveyed in 2010 to examine shifts in tidal marsh extent and *** change varied spatially along the estuary,with watershed changes between a 32%loss and an 11%gain in marsh *** of marsh was apparent in high energy sections of the estuary while there was marsh gain in the upper/riverine section of the estuary and where forested hummocks on marsh islands have become *** showed little change in the small tributary creeks,except in the creeks dominated by fringing marshes and high shoreline ***:Differential resilience to sea-level rise and spatial variations in erosion,sediment supply,and human development have resulted in spatially variable changes in specific marsh extents and are predicted to lead to a redistribution of marshes along the estuarine gradient,with consequences for their unique communities.

关键词： Chesapeake Bay climate change coastal resilience marsh change salt marsh sea-level rise tidal wetlands

mechanical properties of SWNT X-Junctions through molecular dynamics simulation

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International Journal of Smart and Nano materials 2012年第1期3卷 33-46页

作者： B.A.Stormer N.m.Piper X.m.Yang J.Tao Y.Fu m.Kirca A.C.To Department of mechanical Engineering and materials Science&Department of Civil and Environmental Engineering University of PittsburghPittsburghPAUSA Department of Power Engineering North China Electric Power UniversityBaoding 071003China

The mechanical behavior of seven different carbon nanotube(CNT)X-junctions with a varying number of bonds was investigated through molecular dynamics *** X-junctions are composed of two(6,0)single-walled carbon nanotubes(SWNTs)created via vibration-assisted heat *** junctions,containing anywhere between one and seven bonds,are subject to uniaxial tensile,shear and torsional strain,and then the stiffness values are determined for each *** subjected to tensile and shear strain,both the arrangement and orientation of bonds are found to affect the stiffness of junctions more substantially than the number of bonds,bond length or bond ***,anisotropic shear behavior is observed in the X-junctions,which can be attributed to the junction’s bond ***,the stiffness of X-junctions tested under an applied torque(torsion)differs from the stiffness under tensile and shear strain,however,in that it is more substantially affected by the number of bonds present in the junction than by any other property.

关键词： carbon nanotube molecular dynamics X-junction stiffness