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Journal of Rare Earths 2023年第1期41卷 140-148页

作者： Shimaa m.Ali Khadija m.Emran Fedaa m.m.Alrashedee Department of Chemistry Faculty of ScienceCairo University.Giza12613Egypt Department of Chemistry Faculty of ScienceTaibah UniversityMadinah30002Saudi Arabia

A series of undoped and lanthanide doped mIL-53(Fe)/Ln-Fe_(3)O_(4)(Ln=La,Nd,or Gd) metal-organic frameworks(mOFs) were prepared by the solvothermal *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Brunauer-Emmett-Teller(BET) measurements,scanning electron microscopy(SEm),and thermal *** and FT-IR results ascertain the successful mOF formation for all prepared ***-53(Fe)/La-Fe_(3)O_(4) has the smallest particle size of 8.6 nm,the largest BET surface area of 54.2 m^(2)/g,and the highest *** and different lanthanide doped mIL-53(Fe) we re employed as sorbents for the removal of methylene blue(mB)dye from aqueous solutions to examine the doping benefit and the effect of the dopant size on the sorption *** causes mOFs to act as pH-independent sorbents,which make it applicable at any *** follows pseudo-second-order kinetic model,and doped sorbents attain equilibrium *** isotherms are followed,except for mIL-53(Fe)/La-Fe_(3)O_(4).The adsorption capacity increases with increasing the dopant ion size,100.5 mg/g for La-doped mOF,which is about four times higher than that of undoped *** adsorption mechanism involves chemical interactions between Lewis acid in magnetite mIL-53(Fe) series and Lewis base in mB.

关键词： Lanthanide metal organic framework Adsorption Doping Organic dyes Rare earths

Dye-sensitized solar cells based on Cr-doped TiO2 nanotube photoanodes

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Rare metals 2017年第11期36卷 865-871页

作者： m. m. momeni Department of Chemistry Isfahan University of TechnologyIsfahan 84156-83111 Iran

The effect of chromium doping on the photo- voltaic efficiency of dye-sensitized solar cells （DSSCs） with anodized TiO2 nanotubes followed by an annealing process was investigated. Cr-doped TiO2 nanotubes （CrTNs） with different amounts of chromium were obtained by anodizing of titanium foils in a single-step process using potassium chro- mate as the chromium source. Film features were investigated by scanning electron microscopy （SEm）, X-ray diffraction （XRD）, energy-dispersive X-ray spectroscopy （EDX）, and ultraviolet-visible （UV-Vis） spectroscopy. It is clearly seen that highly ordered TiO2 nanotubes are formed in an anodizing solution free of potassium chromate, and with a gradual increase in the potassium chromate concentration, these nanotube structures change to nanoporous and compact films without porosity. The photovoltaic efficiencies of fabricated DSSCs were characterized by a solar cell measurement sys- tem via the photocurrent-voltage （l-V） curves. It is found that the photovoltaic efficiency of DSSCs with CrTNsl sample is improved by more than three times compared to that of DSSCs with undoped TNs. The energy conversion efficiency increases from 1.05 % to 3.89 % by doping of chromium.

关键词： Dye-sensitized solar cell Photoanodes Nanotubes Anodization

New ordered mAX phase mo_2 TiAlC_2: Elastic and electronic properties from first-principles

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Chinese Physics B 2016年第10期25卷 323-329页

作者： m A Hadi m S Ali Department of Physics University of Rajshahi Department of Physics Pabna University of Science and Technology

First-principles computation on the basis of density functional theory(DFT) is executed with the CASTEP code to explore the structural, elastic, and electronic properties along with Debye temperature and theoretical Vickers’ hardness of newly discovered ordered mAX phase carbide mo2TiAlC2. The computed structural parameters are very reasonable compared with the experimental results. The mechanical stability is verified by using the computed elastic constants. The brittleness of the compound is indicated by both the Poisson’s and Pugh’s ratios. The new mAX phase is capable of resisting the pressure and tension and also has the clear directional bonding between atoms. The compound shows significant elastic anisotropy. The Debye temperature estimated from elastic moduli(B, G) is found to be 413.6 K. The electronic structure indicates that the bonding nature of mo2TiAlC2is a mixture of covalent and metallic with few ionic characters. The electron charge density map shows a strong directional mo–C–mo covalent bonding associated with a relatively weak Ti–C *** calculated Fermi surface is due to the low-dispersive mo 4d-like bands, which makes the compound a conductive *** hardness of the compound is also evaluated and a high value of 9.01 GPa is an indication of its strong covalent bonding.

关键词： new ordered mAX phase density functional theory calculations Debye temperature Vickers hardness

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血脂的合理检测和分析

德国医学 1995年第2期12卷 103-104页

作者： W.Krone D.müller-wieland 宋玉娥 Klinik Ⅱ und Poliklinik für Innere medizin der Universitat zu Koln Joseph-Stelzmann-Straβe 9D-50924 KolnGermany 同济医科大学附属同济医院

高胆固醇、高血压、吸烟、糖尿病及进食富含饱和脂肪酸和胆固醇的食物被认为是冠心病的危险因素。此外,大多数专家认为,高密度脂蛋白胆固醇(HDL-Ch)降低,同样是冠心病的危险因素。其他危险因素还有血浆纤维蛋白原和α脂蛋白升高、高胰... 详细信息

高胆固醇、高血压、吸烟、糖尿病及进食富含饱和脂肪酸和胆固醇的食物被认为是冠心病的危险因素。此外,大多数专家认为,高密度脂蛋白胆固醇(HDL-Ch)降低,同样是冠心病的危险因素。其他危险因素还有血浆纤维蛋白原和α脂蛋白升高、高胰岛素血症、超重、运动少和不良社会精神因素等。有血脂异常的患者是否需要治疗,如何治疗取决于以下两方面:1.总的心血管危险因素。2.脂质代谢障碍的类型及原因。下列临床资料有助于诊断。病史中应了解有无冠心病或其他心血管疾病,是否有高血压、糖尿病或脂质代谢障碍,心血管病的家族史,烟酒习惯。女性患者要了解妊娠史、绝经期和激素水平。有无肝脏、胰腺疾病、甲状腺或肾脏疾病。体检包括身高、体重、体脂分布、血压及有无脂质代谢障碍所致的肝肿大。

关键词：血脂高脂血症检测诊断

INVESTIGATION OF THE THICKNESS VARIABILITY AND mATERIAL HETEROGENEITY EFFECTS ON FREE VIBRATION OF THE VISCOELASTIC CIRCULAR PLATES

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Acta mechanica Solida Sinica 2013年第1期26卷 83-98页

作者： m.Shariyat A.A.Jafari m.m.Alipour Faculty of mechanical Engineering K.N.Toosi University of Technology

The present study deals with free vibration analysis of variable thickness viscoelastic circular plates made of heterogeneous materials and resting on two-parameter elastic foundations in addition to their edge conditions. It is assumed that the viscoelastic material properties vary in the transverse and radial directions simultaneously. The complex modulus approach is employed in conjunction with the elastic-viscoelastic correspondence principle to obtain the solution. The governing equations are solved by means of a power series solution. Finally, a sensitivity analysis including evaluation of effects of various edge conditions, thickness variations, coefficients of the elastic foundation, and material loss factor and heterogeneity on the natural frequencies and modal loss factors is accomplished.

关键词： viscoelastic variable thickness circular plate natural frequencies elastic foundation material heterogeneity power series solution

Nuclear radiation shielding effectiveness and corrosion behavior of some steel alloys for nuclear reactor systems

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Defence Technology（防务技术） 2019年第4期15卷 621-628页

作者： m.m. Sadawy R.m. El Shazly mining and Petroleum Engineering Department Al-Azhar University Nasr City Cairo 11371 Egypt Physics Department Faculty of Science Al-Azhar University Nasr City Cairo 11884 Egypt

Different types of nuclear parameters and corrosion behavior were deduced for carbon steel(AISI 1018),austenitic(304 SS),and duplex(2507 SS)stainless steel *** types of neutron energies as well as nine gamma ray energy lines(121.78-1407.92 keV)were used to evaluate the macroscopic neutron cross-sections(∑,cm^-1)and mass attenuation coefficients[σ,cm^2·g^-1)of gamma ray *** corrosion behavior was investigated using different electrochemical *** results showed that the stainless-steel alloys had a good attitude than that of carbon steel alloy for neutron and gamma ray parameters,especially the duplex stainless *** calculated values of mass attenuation coefficient using WinXcom computer program(Version 3.1),exhibited a very good agreement with the experimental values of that ***,the results indicated that duplex stainless-steel exhibited corrosion resistance higher than 304 SS and AISI 1018 steel alloys.

关键词： Steel alloys macroscopic cross-section mass attenuation coefficient Passive film Pitting

丙型肝炎——诊断与治疗的准则德国肝炎协作组在第9届病毒性肝炎和肝病研讨会的专家发言

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德国医学 1997年第3期14卷 140-142页

作者： E.wieland 郝连杰 Tiergartenstr.17 D-69121 HeidelbergGermany 同济医科大学附属同济医院

根据迄今的资料丙型肝炎是一全球分布的疾病,现在已是新发病毒性肝炎中最常见的类型。在慢性病毒性肝炎中丙型肝炎病毒感染起着主导地位,占70％～80％。在德国至少有500000人遭受丙型肝炎病毒感染。一般人群中的感染率为0.05％,每年疫... 详细信息

根据迄今的资料丙型肝炎是一全球分布的疾病,现在已是新发病毒性肝炎中最常见的类型。在慢性病毒性肝炎中丙型肝炎病毒感染起着主导地位,占70％～80％。在德国至少有500000人遭受丙型肝炎病毒感染。一般人群中的感染率为0.05％,每年疫情报告约有2000～3000HCV新感染者。

关键词：肝炎丙型肝炎诊断治疗

Study of magnetic and optical properties of Zn1-xTmxTe(Tm = mn,Fe,Co,Ni) diluted magnetic semiconductors：First principle approach

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Chinese Physics B 2017年第2期26卷 452-460页

作者： Q mahmood m Hassan m A Faridi Department of Physics University of the Punjab Quaid-e-Azam Campus-54590 Lahore Pakistan Centre for High Energy Physics University of the Punjab Lahore Pakistan

We present structural,magnetic and optical characteristics of Zn_（1-x）Tm_xTe（Tm = mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） *** optimization of the crystal structures have been done to compare the ferromagnetic（Fm） and antiferromagnetic（AFm） ground state energies,to elucidate the ferromagnetic phase stability,which further has been verified through the formation and cohesive ***,the estimated Curie temperatures T_c have demonstrated above room temperature ferromagnetism（RTFm） in Zn_（1-x）Tm_xTe（Tm =mn,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that mn- and Co-doped ZnTe behave as ferromagnetic semiconductors,while half-metallic ferromagnetic behaviors are observed in Fe- and Ni-doped *** presence of ferromagnetism is also demonstrated to be due to both the p-d and s-d hybridizations between the host lattice cations and Tm *** calculated band gaps and static real dielectric constants have been observed to vary according to Penn＇s *** evaluated band gaps lie in near visible and ultraviolet regions,which make these materials suitable for various important device applications in optoelectronic and spintronic.

关键词： magnetic semiconductors density functional theory optical and dielectric properties electron density of states and band structure of crystalline solids

Finite deformation swelling of a temperature-sensitive hydrogel cylinder under combined extension-torsion

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Applied mathematics and mechanics(English Edition) 2020年第3期41卷 409-424页

作者： m.SHOJAEIFARD m.BAGHANI College of Engineering University of TehranTehran ***Iran

The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAm) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytical solution is proposed for general combined loading. A finite element(FE) analysis is conducted, subjecting a hydrogel cylinder to the combined extension-torsion and the varied temperature to evaluate the validity and accuracy of the solution. A user-defined UHYPER subroutine is developed and verified under free and constrained swelling conditions. The FE results illustrate excellent agreement with the semi-analytical solution. Due to the complexity of the problem, some compositions and applied loading factors are analyzed. It is revealed that for larger cross-linked density and larger ending temperature, the cylinder yields higher stresses and smaller radial swelling deformation. Besides, the radial and hoop stresses increase by applying larger twist and axial stretch. The hoop stresses intersect at approximately R/Rout = 0.58, where the hoop stress vanishes. Besides, the axial force has direct and inverse relationships with the axial stretch and the twist, respectively. However, the resultant torsional moment behavior is complex, and the position of the maximum point varies significantly by altering the axial stretch and the twist.

关键词： extension-torsion of the circular cylinder temperature variation finite element(FE)analysis temperature-sensitive poly-N-isopropylacrylamide(PNIPAm)hydrogel semi-analytical solution

mF-DFA Analysis of Turbulent Transport measured by a multipurpose Probe

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Chinese Physics Letters 2015年第10期32卷 76-79页

作者： Lafouti m Ghoranneviss m Department of Physics Damavand Branch Islamic Azad University Damavand Iran Plasma Physics Research Center Science and Research Branch Islamic Azad University Tehran Iran

The effect of time of applied bias on the edge turbulent transport is analyzed by the multi-fractal detrend fluctu- ation analysis （mF-DFA） method in the IR-Tl tokamak. The generalized Hurst exponents and the multifractal spectrum are computed by this method. The mF-DFA method is applied to the fluctuation of gradient of float- ing potential time series collected by a multipurpose probe. Tile monofractality or multifractality of the time series can be detected by generalized exponent. The multifractal spectrum describes the singularity content of the process. The results show that with applying bias to the plasma at different times （t = 15 ms, 18ms and 22ms）, the degree of multifractality changes. It reaches the minimum when the bias is applied at t = 18 ms. The multifractality source of data is investigated by the surrogate method （phase randomization techniques）. The surrogate method can destroy the different types of correlations in all the sizes of fluctuations. The results show that the long-range correlation contributes more to multifractality than the fat tail distribution.

关键词： Time series