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Bayesian Regularization Neural Networks for Prediction of Austenite Formation Temperatures(A_(c1) and A_(c3))

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Journal of Iron and Steel Research International 2014年第2期21卷 246-251页

作者： Masoud RAKHSHKHORSHID sayyed-Amin TEIMOURI SENDESI Department of Mechanical Engineering Birjand University of Technology Department of Mechanical Engineering Roudbar BranchIslamic Azad University

A neural network with a feed forward topology and Bayesian regularization training algorithm is used to predict the austenite formation temperatures （At1 and A13） by considering the percentage of alloying elements in chemical composition of steel. The data base used here involves a large variety of different steel types such as struc- tural steels, stainless steels, rail steels, spring steels, high temperature creep resisting steels and tool steels. Scatter diagrams and mean relative error （MRE） statistical criteria are used to compare the performance of developed neural network with the results of Andrew% empirical equations and a feed forward neural network with ＂gradient descent with momentum＂ training algorithm. The results showed that Bayesian regularization neural network has the best performance. Also, due to the satisfactory results of the developed neural network, it was used to investigate the effect of the chemical composition on Ac1 and At3 temperatures. Results are in accordance with materials science theories.

关键词： Bayesian regularization neural network steel chemical composition Ac1 Ae3

Fabrication of Bulk (Fe,Cr)_3Al/Al_2O_3 Intermetallic Matrix Nanocomposite Through Mechanical Alloying and Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 911-919页

作者： sayyed Erfan Aghili Mohammad Hossein Enayati Fathallah Karimzadeh Department of Materials Engineering Isfahan University of Technology

In the present study, （Fe,Cr）3Al/20 vol% A1203 nanocomposite was prepared through mechanochemical reactions during ball milling and successfully bulked using a combination of cold isostatic press and sintering at 1400℃ for 1 h. Two processing approaches were utilized to produce （Fe,Cr）3A1/A1203 nanocomposite： The first was milling of Fe, Cr, AI and Fe203, while the second one was milling of Fe, Cr, Al and Cr203, both in stoichiometric condition, to synthesize （Fe,Cr）3Al/20 vol% Al2O3. Structural changes of powder particles during mechanical alloying were studied by X-ray diffraction. The microstructure and the morphology of powder particles and bulk samples were also studied by scanning electron microscopy and transmission electron microscopy. Microstructural analysis showed that mechanochemical reactions took place during milling, and nanometric Al2O3 was uniformly distributed in the matrix. The results also showed that the second approach required a considerably higher milling time to produce （Fe,Cr）3Al/Al2O3 nanocomposite, as compared to the first one. For this reason, bulk samples were produced from the synthesized nanocomposite in the first approach. The microstructure of the sintered samples consisted of a network structure of （Fe,Cr）3Al and Al2O3 phases with superior mechanical properties.

关键词： Iron aluminide Mechanical alloying Nanocomposite Mechanochemical treatment

Design of an Optical Water Pollution Sensor Using a Single-Layer Guided-Mode Resonance Filter

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Photonic Sensors 2013年第3期3卷 224-230页

作者： Edward SADER Abdallah sayyed-AHMAD Department of Physics Birzeit University Birzeit Palestine

The optical characteristics of a simple, planar, single layer, dielectric Mg-based guided mode resonance filter （GMRF） were investigated by means of rigorous-coupled wave analysis （RCWA）. This filter has great potential for real-life applications, especially as bio- and environmental sensors. The structure of the proposed sensor is compact, and all of its layers can be grown in a single process. In this paper, we present results on the design of a water pollution sensor in the violet region of the visible spectrum. The spectral and angular sensitivities of the sensor for both the transverse electric （TE） and transverse magnetic （TM） polarization modes were estimated and compared for various regions in the violet spectrum. A spectral response characterized with a narrow bandwidth and low reflection side bands was realized by carrying out extensive parameter search and optimization. Optimal spectral and angular sensitivities were found for the sensor with a grating thickness of 100nm in the TM polarized mode where we found them to be 100nm and 40 degrees, per index refraction unit, respectively.

关键词： Diffractive optics guided waves filters sensors spectral sensitivity angular sensitivity

Allantoin attenuates deficits of behavioural and motor nerve conduction in an animal model of cisplatin-induced neurotoxicity in rats

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Animal Models and Experimental Medicine 2019年第2期2卷 114-120页

作者： Vindya N S aqib Mohamad Rema Razdan Department of Pharmacology Al-Ameen College of Pharmacy

Background: The aim of the present study was to evaluate the neuroprotective effect of allantoin in cisplatin‐induced toxicity in rats. Methods: Adult male Wistar rats weighing 160‐200 g were used. Neuropathy was induced by injecting cisplatin (2 mg/kg, ip, twice a week for 6 weeks) and the rats were concurrently treated with allantoin (200 and 400 mg/kg, po) for 8 weeks. At the end of the study, body weight and hemogram were measured. Behavioural tests were performed, including tests for cold and hot hyperalgesia, motor co‐ordination, locomotor activity, mechano‐tactile allodynia and mechanical hyperalgesia. The rats were then sacrificed and sciatic nerve conduction velocity was determined. The antioxidant enzyme and nitric oxide levels in sciatic nerve homogenates were measured. Results: In this study, allantoin restored the motor nerve conduction velocity deficits induced by cisplatin, and the allantoin‐treated rats showed improvement in cold and thermal hyperalgesia, mechano‐tactile allodynia, and mechanical hyperalgesia. Allantoin treatment also improved the rats’ hematological status, increasing haemoglobin, platelet and RBC counts compared to the cisplatin‐treated group. Allantoin treatment also mitigated the functional abnormalities seen in the cisplatin neuropathy group, protecting neurons from the neurotoxic effects of cisplatin. Conclusion: Allantoin shows promise for use as an adjuvant drug in cancer treatment to protect against cisplatin‐induced neuropathy.

关键词： allantoin cisplatin neurotoxicity rats

Response of basement wall in tall buildings foundation under lateral loading

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Frontiers of Structural and Civil Engineering 2022年第11期16卷 1415-1423页

作者： Irfan JAMIL Irshad AHMAD Aqeel Ur REHMAN aqib AHMED Ameer HAMZA Wali ULLAH Department of Civil Engineering University of Engineering and TechnologyPeshawar 25000Pakistan

With increasing population and limitation of availability of land,tall buildings supported on piled raft foundations are increasingly used in the modern *** increase the ratio of floor area to height,and to fulfill storage and parking facilities requirements,these tall buildings usually have more than one basement ***,during the foundation design,engineers have not considered the basement wall contribution to resisting lateral load induced by earthquake or wind and this can result in an uneconomical construction of *** this research work,an experimental study was performed on small-scale models,in order to study basement wall contribution,and the raft contribution including for piled raft foundations,to resisting lateral *** configurations of piles in 2×2,2×3,and 3×3 patterns were tested as a pile group,piled raft and piled raft with a basement *** show that when a basement wall is present,the lateral displacement decreases and the demand on each pile *** piled raft design can become more economical for tall buildings if the basement’s walls are taken into account.

关键词： basement wall lateral load displacement piled raft

Remarkably Improved Gas Separation Performance of Polyimides by Forming“Bent and Battered”Main Chain Using Paracyclophane as Building Block

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高分子科学:英文版 2023年第10期41卷 1617-1628页

作者： Lu-Jun Huang Ya-Tao Weng aqib Raiz Zhi-Jie Mao Xiao-Hua Ma State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin300387China School of Materials Science and Engineering Tiangong UniversityTianjin300387China Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science&Technology Normal UniversityNanchang330013China

The design and development of highly permeable,selective and stable polymer membranes are great challenges in the gas separation ***,we constructed two intrinsic microporous polyimides(6FPCA and 6FMCA)derived from two isometric diamines(PCA and MCA),which were synthesized by palladium catalyzed C—N coupling *** PCA and MCA diamines contain a hollow beaded structure of 2,2′-paracyclophane as a building block with a specified window size of 3.09Å.The chemical structures of monomers,polyimides were confirmed by NMR,FTIR,and elementary analysis.6FPCA and 6FMCA exhibit good solubility,excellent thermal stability,and mechanical properties.6FPCA exhibits much larger microporosity(434 versus 120 m2·g−1),FFV(0.22 versus 0.15),d-spacing(6.9 versus 5.9Å),and over 10 times higher permeability with a very little decrease in selectivity than the corresponding polyimide(6FpA)with a plane structure,which remarkably increased their separation performance from far below the 2008 Robeson Upper bounds to reach these limitations for O2/N2 and CO2/***,the 6FPCA also demonstrates good plasticization resistance,moderate aging properties,and high CO2/CH4 mixed-gas separation *** results indicate that paracyclophane subunit can be successfully incorporated into polymers to enhance their ultra-microporosity and separation properties,which open a new avenue for developing high performance gas separation membranes with topological ultra-micropores.

关键词： Polyimide of intrinsic microporosity 2,2'-Paracyclophane Molecular intrinsic microporosity Gas separation Permeability/selectivity trade-off

Deactivation studies of nano-structured iron catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第3期19卷 333-340页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi University of Mashhad Research Institute of Petroleum Industry of National Iranian Oil Company

A nano-structured iron catalyst for syngas conversion to hydrocarbons in Fischer-Tropsch synthesis（FTS） was prepared by micro-emulsion *** of bulk iron phase and phase transformations of carbonaceous species during catalyst deactivation in FTS reaction were characterized by temperature-programmed surface reaction with hydrogen（TPSR-H 2 ）,and XRD *** carbonaceous species on surface and bulk of the nano-structured iron catalysts were completely identified by combined TPSR-H 2 and XRD spectra and which were compared with those recorded on conventional co-precipitated iron *** results reveal that the catalyst deactivation results from the formation of inactive carbide phases and surface carbonaceous species like graphite,and it will be increased when the particle size of iron oxides was reduced in FTS iron catalyst.

关键词： Fischer-Tropsch synthesis iron-based catalyst catalyst deactivation nano-size particles

Fischer-Tropsch synthesis by nano-structured iron catalyst

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Journal of Natural Gas Chemistry 2010年第3期19卷 284-292页

Effects of nanoscale iron oxide particles on textural structure,reduction,carburization and catalytic behavior of precipitated iron catalyst in Fischer-Tropsch synthesis（FTS） are *** iron catalysts were prepared by microemulsion method in two ***,Fe2O3 ,CuO and La2O3 nanoparticles were prepared separately and were mixed to attain Fe/Cu/La nanostructured catalyst（sep-nano catalyst）;Secondly nanostructured catalyst was prepared by co-precipitation in a water-in-oil microemulsion method（mix-nano catalyst）.Also,conventional iron catalyst was prepared with common co-precipitation *** characterizations of the catalysts were performed by TEM,XRD,H2 and CO-TPR *** size of iron oxides for sep-nano and mix-nano catalysts,which were determined by XRD pattern（Scherrer equation） and TEM images was about 20 and 21.6 nm,*** evaluation was conducted in a fixed-bed stainless steel reactor and compared with conventional iron *** results revealed that FTS reaction increased while WGS reaction and olefin/paraffin ratio decreased in nanostructured iron catalysts.

关键词： Fischer-Tropsch synthesis iron-based catalyst nano-particle

Effect of nano-particle size on product distribution and kinetic parameters of Fe/Cu/La catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第2期19卷 107-116页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi University of MashhadP.O.Box 91775-1436MashhadIran Research Institute of Petroleum Industry of National Iranian Oil Company P.O.Box 14665-137TehranIran

Effects of nano-particle size on hydrocarbon production rates and distributions for precipitated Fe/Cu/La catalysts in Fischer-Tropsch synthesis were ***-structured iron catalyst was prepared by micro-emulsion *** concept of two superimposed AndersonSchulz-Flory （ASF） distributions has been applied for the representation of the effects of reaction conditions and nano-particles size on kinetics parameters and product *** results reveal that by reducing the particle size of catalyst,the break in ASF distributions was *** useful different kinetics equations for synthesis of C3 to C9 and C10 to C22 were determined by using α1 and α2 chain growth probabilities.

关键词： chain length distribution Fischer-Tropsch synthesis iron-based catalyst nano-particle size