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Chinese Chemical Letters 2011年第2期22卷 201-204页

作者： hassan Ali Zamani Department of Applied Chemistry Quchan BranchIslamic Azad UniversityQuchanIran

In this research,a new poly（vinyl chloride）（PVC） membrane sensor for Ho^3＋ ion based on N-phenyl-2-（thiophen-2- ylmethylene）hydrazinecarbothioamide（PHC） as an ionophore was *** sensor demonstrated good selectivity and sensitivity towards the holmium ion in comparison with variety of cations,including alkali,alkaline earth,transition and heavy metal *** effect of membrane composition and pH on the response properties of the electrode was *** detail,the suggested sensor exhibited a Nernstian behavior（with a slope of 20.4±0.3 mV decade^-1） in the range of 1.0×10^-6 to 1.0×10^-2 mol/L with a detection limit of 6.2×10^-7 mol/*** response time was relatively quick in the whole concentration range（～5 s）.The sensor usage was found to be at least 10 weeks in a pH range of *** was successfully applied in determination of fluoride ions in mouth wash preparations.

关键词： Sensor PVC membrane Ion-selective electrode Potentiometry

Erbium(Ⅲ) PVC membrane sensor based on N-(benzyloxycarbonyloxy)succinimide as a new neutral ionophore

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Chinese Chemical Letters 2011年第3期22卷 346-349页

作者： hassan Ali Zamani Department of Applied Chemistry Quchan BranchIslamic Azad UniversityQuchanIran

In this study,a new Er^3＋ sensor based on N-（benzyloxycarbonyloxy）succinimide（BCS） as a neutral carrier has been constructed. The sensor exhibits potential linear response with a Nernstian slope of 20.5±0.4 mV/decade in the concentration range of 1.0×10^-6to 1.0×10^-2mol/L of Er^3＋.It has a very short response time（10 s）,detection limit of 6.3×10^-7 mol/L and a good selectivity relative to a wide variety of other metal ions including common alkali,alkaline earth,heavy,and transition metal *** can be used in the pH range of 2.5-10.6 without any considerable divergence in *** proposed sensor was successfully applied for the recovery of Er^3＋ ions spiked in tap and river water samples.

关键词： Sensor Potentiometry Ion-selective electrode PVC membrane

Dynamic Improvement of DC Microgrids Using a Dual Approach Based on Virtual Inertia

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 667-677页

作者： Mehran Jami Qobad Shafiee hassan Bevrani College of Science HealthEngineeringand EducationMurdoch UniversityWA6150Australia

In this paper,inspired by the concept of virtual inertia in alternating current(AC)systems,a virtual impedance controller is proposed for the dynamic improvement of direct current microgrids(DCMGs).A simple and inexpensive method for injecting inertia into the system is used to adjust the output power of each distributed generation unit without using additional *** proposed controller consists of two components:a virtual capacitor and a virtual *** virtual components can change the rate of change of the DC bus voltage and also improve the transient response.A small-signal analysis is carried out to verify the impact of the proposed control *** simulation studies validate the effectiveness of the proposed solution for increasing the inertia of DCMGs.

关键词： DC microgrid dynamic response virtual impedance virtual inertia

Aerodynamic investigation of twist angle variation based on wing smarting for a flying wing

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Chinese Journal of Aeronautics 2021年第2期34卷 201-216页

作者： Ruhollah KARIMI KELAYEH Mohammad hassan DJAVARESHKIAN Department of Mechanical Engineering Ferdowsi University of MashhadMashhadIran

In this paper, the effects of twist angle variation on aerodynamic coefficients and flow field on the wing with wing smarting approach are studied using numerical simulation. The simulation was performed using incompressible Reynolds-Averaged Navier-Stokes(RANS) equations based on the two-equation k-x Shear Stress Transport(SST) turbulent model for flow speed30 m/s and a Reynolds number of 69000. Investigations have been carried out for several twist angles and at a specific range of angles of attack. The twist applied is the type of geometric twist(wash-out), which is linearly distributed along the span. The test case is a lambda-shaped tailless aircraft with a wing fracture on the trailing edge, and a sweep angle 56°. The results show that with increasing twist angle, the aerodynamic efficiency improves over a wide range of angles of attack,but at 0° angle of attack it will decrease significantly. By increasing the angle of attack, the effect of twist on the flow field and aerodynamic coefficients will gradually decrease;hence, at a certain amount of angle of attack, the effect of twist will stop, that angle is called the neutral brink *** stability analysis shows that by growing the twist angle, the conditions required for longitudinal stability are satisfied, and the pitch-up phenomenon will be delayed.

关键词： Aerodynamics Flying wing Twist Wing smarting Numerical simulation

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

Application of rock mass classification systems to rock slope stability assessment:A case study

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 993-1009页

作者： hassan Basahel Hani Mitri Department of Mining and Materials Engineering McGill UniversityMontrealH3A 0E8Canada

The stability of rock slopes is considered crucial to public safety in highways passing through rock cuts, as well as to personnel and equipment safety in open pit mines. Slope instability and failures occur due to many factors such as adverse slope geometries, geological discontinuities, weak or weathered slope materials as well as severe weather conditions. External loads like heavy precipitation and seismicity could play a significant role in slope failure. In this paper, several rock mass classification systems developed for rock slope stability assessment are evaluated against known rock slope conditions in a region of Saudi Arabia, where slopes located in rugged terrains with complex geometry serve as highway road cuts. Selected empirical methods have been applied to 22 rock cuts that are selected based on their failure mechanisms and slope materials. The stability conditions are identified, and the results of each rock slope classification system are compared. The paper also highlights the limitations of the empirical classification methods used in the study and proposes future research directions.

关键词： Rock mass classification Graphical slope mass rating Continuous slope mass rating Rock slope stability

Steel rings as seismic fuses for enhancing ductility of cross braced frames

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 1103-1117页

作者： Farhad Behnamfar Saeid Arman hassan Zibasokhan Department of Civil Engineering Isfahan University of TechnologyIsfahan ***Iran Department of Civil Engineering Kermanshah University of TechnologyKermanshah ***Iran

A new remedy is proposed in this study to increase the ductility of cross-braced frames to a level comparable with ductile moment *** suggested system consists of one or two concentric steel rings installed in the cross-braced bay *** steel rings are designed such that they fail in bending sooner than failure of the braces in *** the rings act as seismic fuses with multiple bending plastic *** nonlinear static analysis,it is shown that the proposed system can be designed to behave like cross-braced frames with regard to stiffness and strength,and like special moment frames with regard to *** design factors for the proposed system are recommended based on nonlinear pushover and cyclic analysis studies.

关键词： cross brace special moment frame steel ring seismic fuse ductility

On a New Version of Weibull Model:Statistical Properties,Parameter Estimation and Applications

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2219-2241页

作者： hassan Okasha Mazen Nassar Department of Statistics Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azhar UniversityNasr CityCairo11884Egypt Department of Statistics Faculty of CommerceZagazig UniversityZagazig44519Egypt

In this paper,we introduce a new four-parameter version of the traditional Weibull *** is able to provide seven shapes of hazard rate,including constant,decreasing,increasing,unimodal,bathtub,unimodal then bathtub,and bathtub then unimodal *** basic characteristics of the proposedmodel are studied,including moments,entropies,mean deviations and order statistics,and its parameters are estimated using the maximum likelihood *** on the asymptotic properties of the estimators,the approximate confidence intervals are also taken into consideration in addition to the point *** examine the effectiveness of the maximum likelihood estimators of the model’s parameters through simulation *** on the simulation findings,it can be concluded that the provided estimators are consistent and that asymptotic normality is a good method to get the interval *** actual data sets for COVID-19,engineering and blood cancer are used to empirically demonstrate the new distribution’s usefulness inmodeling real-world *** analysis demonstrates the proposed distribution’s ability in modeling many forms of data as opposed to some of its well-known sub-models,such as alpha powerWeibull distribution.

关键词： Weibull distribution alpha power transformation method maximum likelihood entropy order statistics

Mineralogy, Geochemistry and Geotectonic of Plagiogranites from Shahre-Babak Ophiolite, Zagros Zone, Iran

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Journal of Earth Science 2016年第3期27卷 507-518页

作者： Fatemeh Sepidbar hassan Mirnejad Department of Geology University of Tehran Department of Earth and Environmental Earth Sciences Miami University

Shahre-Babak ophiolite is a part of the inner Zagros ophiolite belt in Iran. Major parts of intrusive masses of Share-Babak ophiolite are gabbro and plagiogranite. The SiO2 versus Na2O＋K2O diagram shows that the palgiogranites are related to calk-alkaline series. Rare earth elements exhibit relatively similar pattern that indicates these rocks are syngenetic. Also, REE patterns display an enrichment of LREE compared to HREE, and are characterized by flat to slightly concaveup patterns from Gd to Yb. Such patterns contrast sharply with those of plagiogranites in more complete ophiolite sequences, such as the Semail ophiolite, Oman, or the Troodos ophiolite, Cyprus, and Neyriz, where patterns are much flatter and slightly LREE-depleted. The slightly LREE-enriched patterns of the Shahre-Babak plagiogranites support a partial melting origin for them. The low TiO2, Nb, Ta content and high LREE concentrations of the Shahre-Babak plagiogranites indicate that the rocks were likely derived from the anatexis of amphibolites, which were related to hydrothermal alteration of gabbros in intra-oceanic back-arc basin.

关键词： plagiogranite back-arc basin Share-Babak ophiolite Neo-Tethys Iran

Containment Problem for Quasi Star Configurations of Points in P^2

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Algebra Colloquium 2018年第4期25卷 661-670页

作者： hassan Haghighi Mohammad Mosakhani Faculty of Mathematics K.N.Toosi University of TechnologyTehranIran

In this paper,the containment problem for the defining ideal of a special type of zero-dimensional subscheme of P^2,the so-called quasi star configuration,is *** sharp bounds for the resurgence of these types of ideals are *** an application of this result,for every real number 0<ε<1/2,we construct an infinite family of homogeneous radical ideals of points in K[P^2]such that their resurgences lie in the interval[2-ε,2).Moreover,the Castelnuovo-Mumford regularity of all ordinary powers of defining ideal of quasi star configurations are *** particular,it is shown that all of these ordinary powers have a linear resolution.

关键词： symbolic power resurgence Waldschmidt constant quasi star configuration containment problem