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Experimental investigation of flow and distortion mitigation by mechanical vortex generators in a coupled serpentine inlet-turbofan engine system

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Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： iman MAGHSOUDI Mohammad Ali VAZIRY Mostafa MAHMOODI Department of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Department of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The performance of compact,aggressive ducts in advanced propulsion systems is limited by the internal flow separation coupled with the formation of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experimental investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynamic Interface Plane (AIP) distortion in a serpentine air inlet *** were performed by a turbofan engine at several Engine Operating Points (EOPs) from 56%(idle) to 100%(max).A large total pressure deficit region arose at the upper part of the AIP,which was associated with the upper surface flow *** the new mechanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were diminished at the upper part of the duct and *** VG2 arrangement attained the maximum reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P metrics,*** the next step of the study,some unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachment points were determined by the standard deviation of static pressure on the upper *** AIP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dominated by the maximum ***,the PSD diagram of several probes at AIP revealed the vortex shedding frequency and its higher harmonics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the improvement of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

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Chinese Journal of Chemical Engineering 2022年第4期35卷 253-259页

作者： iman farirzadeh Majid Riahi Samani Davood Toghraie Department of Civil Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous *** tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were *** results showed that all composites were more efficient in lead removal compared to the fruit peels *** highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene *** composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and freundlich models,but the Langmuir model was more fitted than ***,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(fTIR analysis),were studied.

关键词： Adsorption Banana peel Composites Pollution Polyaniline

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam based on experimental and numerical analyses

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frontiers of Structural and Civil Engineering 2020年第3期14卷 675-689页

作者： iman fATTAHI Hamid Reza MIRDAMADI Hamid ABDOLLAHI Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial *** this article,equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite *** this model,both displacement and strain fields are decomposed into cross-sectional and longitudinal components,called consistent geometric decomposition ***,the model is discretized using finite clement *** local coordinate systems and a global one are defined to decouple mechanical degrees of ***,from the viewpoint of consistent geometric decomposition theorem,the transformation and element mass matrices for those systems are introduced here for the first *** same decomposition idea can be used for developing element stiffiness ***,comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam dynamic finite element degrees of freedom coupling experimental validation numerical validation

Development of the applicability of simplified Henry’s method for skewed multicell box-girder bridges under traffic loading conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 915-925页

作者： iman MOHSENI A.R.Khalim RASHID Department of Civil Engineering Universiti Kebangsaan Malaysia(National University of Malaysia)

Concrete precast multicell box-girder(MCB) bridges combine aesthetics with torsional stiffness *** analytical studies indicate that currently available specifications are unable to consider the effect of the twisting moment(torsional moment) on bridge *** straight bridges the effect of torsion is negligible and the transverse reinforced design is governed by other ***,in the case of skewed bridges the effect of the twisting moment should be ***,an in-depth study was performed on 90 concrete MCB bridges with skew angles ranging from 0° to 60°.for each girder the bridge actions were determined under the American Association of State Highway and Transportation Officials(AASHTO) live load *** analytical results show that torsional stiffness and live load positions greatly affected the bridges' *** addition,based on a statistical analysis of the obtained results,several skew correction factors are proposed to improve the precision of the simplified Henry's method,which is widely used by bridge engineers to predict bridge *** relationship between the bending moment and secondary moments was also investigated and it was concluded that all secondary actions increase with an increase in skewness.

关键词： Distribution factor Live loads Skewed bridges Grillage analysis

A convenient one-pot synthesis of new chromeno[3,4-c]chromene and chromeno[3,4-c]pyridine derivatives in the presence of high surface area of magnesium oxide

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Chinese Chemical Letters 2012年第12期23卷 1327-1330页

作者： iman Mohammadzadeh Hassan Sheibani University of Applied Science and Technology of Kerman Department of Chemistry Shahid Bahonar University of Kerman

In this investigation a new strategy involves the one-pot, three-component reaction of malononitrile, salycilaldehyde and phenol derivatives in the presence of high surface area of MgO is extended to the formation of chromeno[3,4-c]ehromene derivatives in good to excellent yields in a short reaction time. Also, the three component reactions of an aldehyde such as salycilaldehyde and ketones with malononitril for the formation of chromeno[3,4-c]pyridines are investigated.

关键词： Salycilaldehyde Chromeno[3,4-c]chromenes 2-Amino-4-aryl pyddylcyanides malononitrile

Annexin A2 as a biomarker for hepatocellular carcinoma in Egyptian patients

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World Journal of Hepatology 2017年第9期9卷 469-476页

作者： Mohamed K Shaker Hanzada I Abdel fattah Ghada S Sabbour iman f Montasser Sara M Abdelhakam Eman el Hadidy Rehab Yousry Ahmed K el Dorry Department of Tropical Medicine Faculty of MedicineAin Shams University Department of Clinical Pathology Faculty of MedicineAin Shams University Department of Radiodiagnosis and Inter-ventional Radiology Faculty of MedicineAin Shams University

AIM To investigate the clinical utility of serum annexin A2(ANXA2) as a diagnostic marker for early hepatocellular carcinoma(HCC).METHODS This study was performed in HCC Clinic of Ain Shams University Hospitals, Cairo, Egypt and included: Group 1: fifty patients with early stage HCC(Barcelona Clinic Liver Cancer stage A); Group 2: Twenty five patients with chronic liver disease; and Control Group: fifteen healthy, age-and sex-matched subjects who were seronegative for viral hepatitis markers. The followinglaboratory investigations were done: Viral hepatitis markers [hepatitis B surface antigen and hepatitis C virus(HCV) antibodies], HCV RNA in HCV antibody-positive patients, serum alpha fetoprotein(AfP), and serum ANXA2 *** In this study, 88% of HCC patients(n = 44) were HCVpositive, while HBV infection represented only 8% of all HCC patients(n = 4); and two patients were negative for both viral markers. A highly significant difference was found between patients with HCC and chronic liver disease as well as controls with regard to serum ANXA2 levels(130, IQR 15-240; 15, IQR 15-17; and 17, IQR 15-30 ng/m L, respectively). The area under the curve of ANXA2 was 0.865; the cut-off value was established to be 18 ng/mL with a diagnostic sensitivity of 74% and a specificity of 88%, while the sensitivity and specificity of AfP at the cut-off value of 200 ng/dL were 20% and 100%, *** Serum ANXA2 may serve as a biomarker for the early detection of HCC.

关键词： Hepatocellular carcinoma Hepatitis C virus Annexin A2 Alpha-fetoprotein Tumor markers

Identification of pulse-like ground motions using artificial neural network

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 899-912页

作者： Ahed Habib iman Youssefi Mehmet M.Kunt Department of Civil Engineering Eastern Mediterranean University99628 FamagustaNorth Cyprusvia Mersin 10Turkey

for more than 20 years,the concept of near-fault pulse-like ground motion has been a topic of great interest due to its distinct characteristics,particularly due to directivity or fling effects,which are hugely influenced by the rupture *** unexpected characteristics,along with their effective frequency,energy rate,and damage indices,create a near-fault,pulse-like ground motion capable of causing severe damage to *** of the most common approaches for identifying these ground motions is done by conducting wavelet decomposition of the ground motion time history to extract a pulse signal and eventually categorize an earthquake by comparing the original signal to the residual ***,to overcome the intensive calculations required in this approach,this study proposes using artificial neural networks to identify pulse-like ground motions through classification to predict their pulse period by means of regression ***,the study is intended to evaluate the reliability and accuracy of various artificial neural networks in identifying pulse-like ground motions and predicting their pulse *** general,the results of the study have shown that the artificial neural network can identify pulse-like earthquakes and reliably predict their pulse period.

关键词： pulse-like ground motions near-fault artificial neural network identification

The effect of ZIf-90 particle in Pebax/Psf composite membrane on the transport properties of CO2,CH4 and N2 gases by Molecular Dynamics Simulation method

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2267-2284页

作者： Ali Hatami iman Salahshoori Niloufar Rashidi Danial Nasirian Department of Chemical Engineering Science and Research BranchIslamicAzad UniversityTehranIran Department of Chemical Engineering Shahreza BranchIslamicAzad UniversityIsfahanIran

Nowadays,mixed matrix membranes(MMMs)have considered by many researchers to overcome the problems of polymeric *** addition,molecular dynamics(MD)and Monte Carlo(MC)simulation Methods are suitable tools for studying transport properties and morphology in *** this purpose,in this study using material studio 2017(MS)software,the transport properties of CO2,CH4 and N2 in Pebax,Psf neat Pebax/Psf composite and Pebax/Psf composite filled with ZIf-90 particles have been *** adding Psf to Pebax matrix,the selectivity of CO2/CH4 and CO2/N2 gases has significantly *** addition,adding ZIf-90 particles to the Pebax/Psf composite increased the permeability of CO2,CH4 and N2 compared to neat and composite *** morphological properties of the membranes,such as the fractional free volume(ffV),radial distribution function(RDf),glass transition temperature(TG),X-ray diffraction(XRD)and equilibrium density have calculated and acceptable results have obtained.

关键词： Separation Mixed Matrix Membranes Molecular Dynamics Monte Carlo Pebax 1656/Psf ZIf-90

Production of Railwayscape in urban environment:Analysing railway heritage tourism potential in Siliguri City,India

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Regional Sustainability 2023年第1期4卷 1-12页

作者： iman BANERJEE Department of Geography Banaras Hindu UniversityVaranasi221005India

for a long time,it has been argued that the theories and practices devoted to urban planning and management should conform to the fundamental role of planning policies in the production of urban space,but not merely the spatial distribution of the produced *** this wider connotation,this study introduces the notion of Railwayscape,grounded on the theory of‘The Production of Space’,to examine the role of railway station districts as catalysts of urban development through the social production of urban *** present research sets out to establish the notion of Railwayscape and apply it in a railway heritage,i.e.,the Darjeeling Himalayan Railway(DHR)and its point of inception,Siliguri City,***,a criteria-based evaluation of four railway station districts(New Jalpaiguri,Siliguri Town,Siliguri Junction,and Sukna)in Siliguri and its surroundings was *** information regarding the selected four railway station districts is obtained through field observation and key informant consultation,supplemented by published literature and remote sensing *** evaluation is succeeded by the strengths,weaknesses,opportunities and threats(SWOT)analysis accentuating the potential strengths,weaknesses,opportunities and threats associated with the selected four railway station districts and their prospects to become the potential *** results of this research show that there is no railway station district in Siliguri that can fully meet the demands of the locals and tourists,therefore,relfecting a lack of awareness of the historical values of these *** results also indicate that there are significant differences in the relative potentials of railway station districts to become the Railwayscape in urban *** outcomes of this research,therefore,are expected to encourage policy-making insitutions and practitioners to realise the‘place value’of some railway station districts and their potentials to yield better econom

关键词： Railwayscape Darjeeling Himalayan Railway(DHR) The production of space Siliguri city Railway heritage tourism potential