Transient heat transfer analysis of functionally graded CNT reinforced cylinders with various boundary conditions

Rasool Moradi-Dastjerdi,Gholamhassan Payganeh 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.24 No.3

In this work, transient heat transfer analysis of functionally graded (FG) carbon nanotube reinforced nanocomposite (CNTRC) cylinders with various essential and natural boundary conditions is investigated by a mesh-free method. The cylinders are subjected to thermal flux, convection environments and constant temperature faces. The material properties of the nanocomposite are estimated by an extended micro mechanical model in volume fraction form. The distribution of carbon nanotube (CNT) has a linear variation along the radial direction of axisymmetric cylinder. In the mesh-free analysis, moving least squares shape functions are used for approximation of temperature field in the weak form of heat transform equation and the transformation method is used for the imposition of essential boundary conditions. Newmark method is applied for solution time depended problem. The effects of CNT distribution pattern and volume fraction, cylinder thickness and boundary conditions are investigated on the transient temperature field of the nanocomposite cylinders.

Novel Zero-Voltage-Switching Bridgeless PFC Converter

Rasool Haghi,Mohammad Reza Zolghadri,Reza Beiranvand 전력전자학회 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.1

In this paper, a new zero-voltage-switching, high power-factor, bridgeless rectifier is introduced. In this topology, an auxiliary circuit provides soft switching for all of the power semiconductor devices. Thus the switching losses are reduced and the highest efficiency can be achieved. The proposed converter has been analyzed and a design procedure has been introduced. The control circuit for the converter has also been developed. Based on the given approach, a 250 W, 400 Vdc prototype converters has been designed at 100 kHz for universal input voltage (90-264 Vrms) applications. A maximum efficiency of 94.6% and a power factor correction over 0.99 has been achieved. The simulation and experimental results confirm the design procedure and highlight the advantages of the proposed topology.

Gender-Related Differences in Reliability of Thorax, Lumbar, and Pelvis Kinematics During Gait in Patients With Non-specific Chronic Low Back Pain

Rasool Bagheri,Ismail Ebrahimi Takamjani,Mehdi Dadgoo,Amir Ahmadi,Javad Sarrafzadeh,Mohammad Reza Pourahmadi,Amir-Salar Jafarpisheh 대한재활의학회 2018 Annals of Rehabilitation Medicine Vol.42 No.2

Objective To evaluate test-retest reliability of trunk kinematics relative to the pelvis during gait in two groups (males and females) of patients with non-specific chronic low back pain (NCLBP) using three-dimensional motion capture system. Methods A convenience sample of 40 NCLBP participants (20 males and 20 females) was evaluated in two sessions. Participants were asked to walk with self-selected speed and kinematics of thorax and lumbar spine were captured using a 6-infrared-cameras motion-analyzer system. Peak amplitude of displacement and its measurement errors and minimal detectable change (MDC) were then calculated. Results Intraclass correlation coefficients (ICCs) were relatively constant but small for certain variables (lower lumbar peak flexion in female: inter-session ICC=0.51 and intra-session ICC=0.68; peak extension in male: intersession ICC=0.67 and intra-session ICC=0.66). The measurement error remained constant and standard error of measurement (SEM) difference was large between males (generally ≤4.8°) and females (generally ≤5.3°). Standard deviation (SD) was higher in females. In most segments, females exhibited higher MDCs except for lower lumbar sagittal movements. Conclusion Although ICCs were sufficiently reliable and constant in both genders during gait, there was difference in SEM due to difference in SD between genders caused by different gait disturbance in chronic low back pain. Due to the increasing tendency of measurement error in other areas of men and women, attention is needed when measuring lumbar motion using the method described in this study.

Amine-Based Interfacial Engineering in Solution-Processed Organic and Perovskite Solar Cells

Rasool, Shafket,Khan, Nasir,Jahankhan, Muhammad,Kim, Da Hun,Ho, Thuy Thi,Do, Ly Thi,Song, Chang Eun,Lee, Hang Ken,Lee, Sang Kyu,Lee, Jong-Cheol,So, Won-Wook,Moon, Sang-Jin,Shin, Won Suk American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.18

<P>Solution-processed organic solar cells (OSCs) and hybrid perovskite solar cells (PvSCs) generally require appropriate transparent electrode with a low work function, which improves the electron extraction, increases the built-in potential, and suppresses charge recombinations. Hence, interfacial modifiers between the cathode and the photoactive layer play a significant role in OSCs and PvSCs, as they provide suitable energy-level alignment, leading to desirable charge carrier selectivity and suppressing charge carrier recombinations at the interfaces. Here, we present a comprehensive study of the energy-level mapping between a transparent electrode and photoactive layers to enhance the electron-transport ability by introducing amine-based interfacial modifiers (ABIMs). Among the ABIMs, polyethylenimine ethoxylated (PEIE) incorporating inverted OSCs shows enhanced power conversion efficiencies (PCEs) from 0.32 to 9.83% due to large interfacial dipole moments, leading to a well-aligned energy level between the cathode and the photoactive layer. Furthermore, we explore the versatility of the PEIE ABIM by employing different photoactive layers with fullerene derivatives, a nonfullerene acceptor, and a perovskite layer. Promisingly, inverted nonfullerene OSCs and planar n-i-p PvSCs with PEIE ABIM show outstanding PCEs of 11.88 and 17.15%, respectively.</P> [FIG OMISSION]</BR>

Preparation and Nutritional Evaluation of Hatchery Waste Meal for Broilers

Rasool, S.,Rehan, M.,Haq, A.,Alam, M.Z. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.4

Hatchery waste including infertile eggs, dead embryos in shell, dead or low grade chicks was cooked at $100^{\circ}C$ for 15 minutes and then oven dried and ground. Hatchery waste meal (HWM) thus prepared contained 44.25% protein, 4,573 kcal/kg gross energy, 3,600 kcal/kg metabolizable energy, 30% ether extract, 1.9% fibre, 14% ash, 9.8% nitrogen free extract, 7.26% Ca, 0.84%P, 1.86% lysine and 0.66% methionine with no Salmonella and E. coli. In biological evaluation trial, significantly higher weight gain was observed in ration containing 12% HWM compared with that containing similar amount of fish meal. Protein efficiency ratio on the two rations was 3.96 vs 2.85; protein digestibility, 86.02 vs 71.9; net protein utilization, 64.9 vs 42.37 and biological value, 75.37 vs 58.84, respectively, indicating better balance of amino acids in HWM compared with fish meal. Growth performance trial on broiler chicks also revealed better weight gain and feed efficiency on ration containing 12% HWM than that containing similar level of fish meal.

Wave propagation in functionally graded composite cylinders reinforced by aggregated carbon nanotube

Rasool Moradi-Dastjerdi 국제구조공학회 2016 Structural Engineering and Mechanics, An Int'l Jou Vol.57 No.3

This work reports wave propagation in the nanocomposite cylinders that reinforced by straight single-walled carbon nanotubes based on a mesh-free method. Moving least square shape functions have been used for approximation of displacement field in weak form of motion equation. The straight carbon nanotubes (CNTs) are assumed to be oriented in specific or random directions or locally aggregated into some clusters. In this simulation, an axisymmetric model is used and also the volume fractions of the CNTs and clusters are assumed to be functionally graded along the thickness. So, material properties of the carbon nanotube reinforced composite cylinders are variable and estimated based on the Eshelby-Mori-Tanaka approach. The effects of orientation, aggregation and volume fractions of the functionally graded clusters and CNTs on dynamic behavior of nanocomposite cylinders are studied. This study results show that orientation and aggregation of CNTs have significant effects on the effective stiffness and dynamic behaviors.

Buckling analysis of plates reinforced by Graphene platelet based on Halpin-Tsai and Reddy theories

Rasool Javani,Mahmood Rabani Bidgoli,Reza Kolahchi 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.31 No.4

In this paper, buckling analyses of composite plate reinforced by Graphen platelate (GPL) is studied. The Halphin- Tsai model is used for obtaining the effective material properties of nano composite plate. The nano composite plate is modeled by Third order shear deformation theory (TSDT). The elastic medium is simulated by Winkler model. Employing nonlinear strains-displacements, stress-strain, the energy equations of plate are obtained and using Hamilton’s principal, the governing equations are derived. The governing equations are solved based on Navier method. The effect of GPL volume percent, geometrical parameters of plate and elastic foundation on the buckling load are investigated. Results showed that with increasing GPLs volume percent, the buckling load increases.

On Zeros of Polynomials with Restricted Coefficients

RASOOL, TAWHEEDA,AHMAD, IRSHAD,LIMAN, AB Department of Mathematics 2015 Kyungpook mathematical journal Vol.55 No.4

Let $P(z)={\limits\sum_{j=0}^{n}}a_jz^j$ be a polynomial of degree n and Re $a_j={\alpha}_j$, Im $a_j=B_j$. In this paper, we have obtained a zero-free region for polynomials in terms of ${\alpha}_j$ and ${\beta}_j$ and also obtain the bound for number of zeros that can lie in a prescribed region.

Association of a VDR Gene Polymorphism with Risk of Colorectal Cancer in Kashmir

Rasool, Sabha,Kadla, Showkat Ahmad,Khan, Tanzeela,Qazi, Falak,Shah, Nisar Ahmad,Basu, Javed,Khan, Bilal Ahmad,Ahktar, Qulsum,Sameer, Aga Syed,Ganai, Bashir Ahmad Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Roles of the vitamin D receptor in etiology of cancers, including colorectal cancer, have been repeatedly stressed in different parts of the world. A case control study aimed to evaluate the relationship between the two was therefore initiated in Kashmir, known both for its increasing incidence of gastrointestinal cancers and deficiency of micro-nutrients especially vitamin D. The study included a total of 617 subjects (312 colorectal cancer cases and 305 controls), with sampling carried out over a period of 5 years. DNA samples from the blood of the subjects were analyzed for start codon Fok I VDR polymorphism. We obtained a 1.3 fold increased risk among individuals homozygous for f variants as compared to subjects homozygous for F allele (odds ratio OR 1.3, 95%CI, 0.861-1.65). Our study also showed statistically significant results when dwelling and tumor location characteristics were stratified with Fok I polymorphism, all of which suggests a possible role of Fok I polymorphism in the etiology of CRC in Kashmir.

Enhanced photostability in polymer solar cells achieved with modified electron transport layer

Rasool, Shafket,Van Doan, Vu,Lee, Hang Ken,Lee, Sang Kyu,Lee, Jong-Cheol,Moon, Sang-Jin,So, Won Wook,Song, Chang Eun,Shin, Won Suk Elsevier 2019 THIN SOLID FILMS - Vol.669 No.-

<P><B>Abstract</B></P> <P>Photostability of the polymer solar cells (PSCs) remains a challenge to attain, as number of factors including the electron transport layers contribute to the degradation of PSCs when they are tested under 1 sun illumination, along with heat and humidity. Especially electron transport layers (ETLs) have considerable contribution to the overall degradations in these solar cells. Most studied ETL into the fabrication of inverted PSCs is zinc oxide (ZnO) yet the photostability of these PSCs is limited. This degradation most probably occurred due to the direct contact of zinc metal with the photoactive layer. This interface between ZnO and photoactive layer results in the initiation of degradations in PSCs. Keeping in view of this issue, we have modified the ZnO ETL by mixing ZnO nano particles with ethoxylated polyethyleneimine (PEIE) and then passivating this modified ZnO (m-ZnO) with ultrathin PEIE buffer layer. The power conversion efficiency is not affected by this approach, but when PSCs were subjected to 1 sun illumination, these m-ZnO/PEIE based PSCs have shown the enhanced light soaking (LS) stability. These findings indicate that optimizing the interface between the photoactive layer and the electron transport layer can lead to enhanced LS stability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ethoxylated polyethylenimine (PEIE) passivated ZnO (m-ZnO) as electron transport layer (ETL). </LI> <LI> The direct contact of ZnO with photoactive layer is avoided. </LI> <LI> The m-ZnO/PEIE layer help in enhanced light soaking (LS) stability. </LI> <LI> The m-ZnO/PEIE layer has nitrogen enriched surface. </LI> <LI> The nitrogen enriched ETL surface contributes to enhanced LS stability. </LI> </UL> </P>