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Journal of Materials Science & Technology 2015年第8期31卷 828-833页

作者： Abbas Sadeghzadeh Attar Zahra hassani Department of Metallurgy and Materials Engineering University of Kashan Department of Materials Institute of Science and High Technology and Environmental SciencesGraduate University of Advanced Technology

TiO2 nanowire arrays were successfully fabricated by liquid-phase deposition method using porous alumina templates. The obtained TiO2 nanowires were characterized using Raman spectroscopy, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, field emission scanning electron microscopy （FE- SEM）, transmission electron microscopy （TEM）, and selected area electron diffraction （SAED） analysis. Results of electron microscopic observations indicated that the nanowires were smooth and uniform with a diameter of about 50-80 nm and several micrometers in length. SAED, Raman, and XRD mea- surements showed that TiO2 nanowires were single-crystalline with a pure rutile structure after heating at 800 ~C for 10 h. In this situation, the nanowire constituents grew preferentially along the 〈001〉 direction. Furthermore, the formation process and mechanistic study of the Ti02 nanowire arrays were proposed and discussed in detail. The nanowires are clearly produced by the deposition of TiO2 particles on the inner wall of the template nanochannels.

关键词： TiO2 nanowire arrays Single crystal Rutile phase Liquid-phase deposition process

Iterative Selection of GOB Poles in the Context of System Modeling

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International Journal of Automation and computing 2019年第1期16卷 102-111页

作者： Anis Khouaja hassani Messaoud High Institute of Applied Science and Technology National Engineering School of Monastir (ENIM)

This paper is concerned with the problem of system identification using expansions on generalized orthonormal bases(GOB). Three algorithms are proposed to optimize the poles of such a basis. The first two algorithms determine a GOB with optimal real poles while the third one determines a GOB with optimal real and complex poles. These algorithms are based on the estimation of the dominant mode associated with a residual signal obtained by iteratively filtering the output of the process to be modelled. These algorithms are iterative and based on the quadratic error between the linear process output and the GOB based model output. They present the advantage to be very simple to implement. No numerical optimization technique is needed, and in consequence there is no problem of local minima as is the case for other algorithms in the literature. The convergence of the proposed algorithms is proved by demonstrating that the modeling quadratic error between the process output and the GOB based model is decreasing at each iteration of the algorithm. The performance of the proposed pole selection algorithms are based on the quadratic error criteria and illustrated by means of simulation results.

关键词： Generalized orthonormal bases(GOB) Laguerre functions Kautz functions pole estimation modelling identification

Microstructural evolution and intermetallic formation in Al-8wt% Si-0.8wt% Fe alloy due to grain refiner and modifier additions

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 739-746页

作者： Amir hassani Khalil Ranjbar Sattar Sami Faculty of Materials Science and Engineering University of Semnan Semnan Iran Materials Department Faculty of Engineering Shahid Chamran University Ahwaz Iran

An alloy of A1-8wt% Si-0.8wt% Fe was cast in a metallic die, and its microstrucmral changes due to Ti-B refiner and Sr modifier additions were studied. Apart from usual refinement and modification of the microstructure, some mutual influences of the additives took place, and no mutual poisoning effects by these additives, in combined form, were observed. It was noticed that the dimensions of the iron-rich intermetallics were influenced by the additives causing them to become larger. The needle-shaped intermetallics that were obtained from refiner addition became thicker and longer when adding the modifier. It was also found that a-Al and eutectic silicon phases preferentially nucleate on different types of intermetallic compounds. The more iron content of the intermetallic compounds and the more changes in their dimensions occurred. Formation of the shrinkage porosities was also observed.

关键词： aluminum alloys metal casting grain refinement modification metallographic microstructure intermetallics

Stresses induced by post-tensioned anchor in jointed rock mass

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Journal of Central South University 2015年第4期22卷 1463-1476页

作者： Alan Showkati Parviz Maarefvand Hossein hassani Faculty of Mining and Metallurgical Engineering Amirkabir University of Technology

A new analytical study on stresses around a post-tensioned anchor in rocks with two perpendicular joint sets is presented. The assumptions of orthotropic elastic rock with plane strain conditions are made in derivation of the formulations. A tri-linear bond-slip constitutive law is used for modeling the tendon-grout interface behavior and debonding of this interface. The bearing plate width is also considered in the analysis. The obtained solutions are in the integral forms and numerical techniques that have been used for evaluation. In the illustrative example given, the major principal stress is compressive in the anchor free zone and compressive stress concentrations of 815 k Pa and 727 k Pa(for the anchor load of 300 k N) are observed under the bearing plate and the bond length proximal end, respectively. However, large values of tensile stresses with the maximum of-434 k Pa are formed at the bond length distal end. The results obtained using the proposed solution are compared very those of numerical method(FEM).

关键词： post-tensioned anchor jointed rock stress distribution analytical solution tri-linear bond-slip model bond length bearing plate

Advanced development in upstream of petroleum industry using nanotechnology

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1483-1491页

作者： Sedigheh Sadegh hassani Maryam Daraee Zahra Sobat Catalysis research Division Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran

Nowadays,energy supply is one of the most important issues due to limitation of oil,gas and coal *** of rapid population,civilization and energy consumption growth,the improved technologies to make optimal use of the sources,solving related problems and finding new energy sources are *** than 10 years ago,nanotechnology as one of the most important technologies has also been applied to progress in the oil and gas industry(upstream,midstream and downstream).The experience of these years has shown that application of nanotechnology in the oil industry improves the exploration of crude oil and natural gas(underground or deep water),drilling and bringing the crude oil or raw natural gas to the surface,as well as transportation,storage,processing and purifying *** with high specific surface area,pore volume and small size show unique physical and chemical properties,which could be applied in several *** this regard,many researchers have been focused on various nanoparticles for upstream industries and studied their potential in oil exploration,drilling,production and enhanced oil recovery(EOR).Also,in downstream and midstream which involve refining of crude oil,processing and purifying of raw natural gas,transportation and storage of crude or refined petroleum products,the nanomaterials have been used to improve the quality of oil and make it appropriate for the *** sulfur gasoline,enhancing the octane number and coating the transportation system are among the goals that have been achieved successfully using *** this work,various types of nanoparticles such as metallic,metal oxide,hybrid nanoparticles,carbon nanomaterials,nano-composites and their applications in oil upstream industry are ***,their usage in different types of oil upstream processes is discussed.

关键词： Nanotechnology Oil exploration Oil drilling Nanoparticles Enhanced oil recovery

Invasive Procedures for Prenatal Diagnosis in Salmaniya Medical Complex in Bahrain:A Retrospective Cross-Sectional Descriptive Study

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The Incidence and Risk Factors of Third- and Fourth-Degree Perineal Tears in Ministry of Health in Bahrain over 5 Years

Open Journal of Obstetrics and Gynecology（妇产科期刊） 2024年第7期 1046页

作者： Basma Alsayegh Bayan Ahmed Fatema Ahmed Amal hassani

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Open Journal of Obstetrics and Gynecology（妇产科期刊） 2024年第7期 1060页

作者： Fatema Ahmed Basma Alsayegh Bayan Ahmed Amal hassani

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Journal of Systems Science & Complexity 2014年第1期27卷 3-20页

作者： hassani Hossein ABDOLLAHZADEH Majid IRANMANESH Hossein MIRANIAN Arash Executive Business Centre Bournemouth University Bournemouth 89 Holdenhurst Road BH8 8EB UK. Department of Mechanical Engineering Pard@ Branch Islamic Azad University Pardis new city TehranIran. Department of Industrial Engineering College of Engineering University of Tehran Iran Institute of Inter-national Energy Studies ( IIES) Tehran Iran. Department of Mechanical Engineering Pardis Branch Islamic Azad University Pardis New City TehranIran.

This paper proposes a selfsimilar local neurofuzzy （SSLNF） model with mutual informati onbased input selection algorithm for the shortterm electricity demand forecasting. The proposed self similar model is composed of a number of local models, each being a local linear neurofuzzy （LLNF） model, and their associated validity functions and can be interpreted itself as an LLNF model. The proposed model is trained by a nested local liner model tree （NLOLIMOT） learning algorithm which partitions the input space into axisorthogonal subdomains and then fits an LLNF model and its associated validity function on each subdomain. Furthermore, the proposed approach allows different input spaces for rule premises （validity functions） and consequents （local models）. This appealing property is employed to assign the candidate input variables （i.e., previous load and temperature） which influence shortterm electricity demand in linear and nonlinear ways to local models and validity functions, respectively. Numerical results from shortterm load forecasting in the New England in 2002 demonstrated the accuracy of the SSLNF model for the STLF applications.

关键词： Mutual information self-similar local neuro-fuzzy model short-term load forecasting.

Influence of vanadium and chromium additions on the wear resistance of a gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 602-607页

作者： A.hassani A.Habibollahzadeh S.Sadeghinejad Materials Science and Engineering Faculty Semnan University

A low-alloy gray cast iron containing hard carbide-forming elements, such as vanadium and chromium, was cast by sand mould casting. Its wear resistance was compared with that of an untreated gray cast iron. Three different loading conditions were tested under a con- stant speed. It was observed that this alloy could reduce the wear loss of standard gray cast iron by up to 89%, which was much greater than what was achieved in previous reports. Scanning electron microscopy （SEM） was used to determine the predominant wear mechanism of both the alloys. In a mild wear regime, the oxidative mechanism was predominant; however, in a severe wear regime, this mechanism was not predominant and the adhesive mechanism was involved. EDX analysis was conducted to evaluate the quantitative amounts of elements in the tribochemical films formed on the wear tracks.

关键词： cast iron wear resistance carbides vanadium chromium

An application of intuitionistic fuzzy sets in medicine

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International Journal of Biomathematics 2016年第3期9卷 81-95页

作者： Bijan Davvaz Elham hassani Sadrabadi Department of MathematicsYazd University Yazd Iran

Intuitionistic fuzzy sets have many applications in different sciences. In this paper we verify one of the applications of intuitionistic fuzzy sets in medical diagnosis according to the ideas of Shannon et al., Wang and Xin, Grzregorzewski, Hung and Yang, and Yang and Chiclana. Actually by using the relationships between intuitionistic fuzzy sets and symptoms of patient we determine the kind of illness and finally we compare the methods.

关键词： Fuzzy set intuitionistic fuzzy set intuitionistic fuzzy relation intuitionisticmedical diagnosis.