International Journal of Material and Mechanical Engineering
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Open Access journal
ISSN (Print) 2162-0695 - ISSN (Online) 2164-280X
Published by Science and Engineering Publishing Company [49 journals]
- A Facile Electrochemical Biosensor for the Detection of microRNA Based on
Abstract: A Facile Electrochemical Biosensor for the Detection of microRNA Based on Graphene Sheets/Polyaniline/AuNPs
Author Xueping ChenDandan ZhouHuawei ShenWenli FengHui ChenGuoming Xi
A facile, highly sensitive electrochemical biosensor was designed to determine microRNA based on graphene sheets/polyaniline/AuNPs (GS/PANI/AuNPs) nanocomposites. Firstly, GS/PANI/AuNPs was synthesized using a one-step and green approach by polymerizing aniline with chloroaurate acid as the oxidant. Then, GS/PANI/AuNPs was re-suspended in chitosan (CS) solution and fabricated onto the surface of glassy carbon electrode (GCE) to enhance the conductivity and immobilize hairpin capture probe (S). In the presence of target RNA, the RNA hybridized with the loop of S, followed by covalently binding of streptavidin-alkaline phosphatase (SA-ALP). Current signal was gained by differential pulse voltammetry (DPV) in the working buffer containing 1-naphthyl phosphate (1-NP). The biosensor exhibited high sensitivity toward microRNA, resulting in a wide linear range from 1.25×10 -12 M to 5×10 -8 M with a detection limit of 0.25 pM (S/N = 3).
- A One-Dimensional Lumped-Mass Model for a Rubber Bushing and Its
Application to the Calculation of Dissipation Energy
Abstract: A One-Dimensional Lumped-Mass Model for a Rubber Bushing and Its Application to the Calculation of Dissipation Energy
Author Zhengui ZhangHaiyan H Zhan
Modal analysis is employed in this paper using hammer impact testing to characterize the dynamic response of rubber bushing. Based on multi-body dynamic analysis and acceleration transfer function, the rubber core is decomposed into three pieces, which are joined by spring and dashpot considering the large deformation and damping properties. Parameters of mass, stiffness and damping coefficients are identified through fitting against the Bode plot of the transfer function. With those parameters, the stability of this structure can be evaluated by exploring the critical excitation frequency range, which attributes the failure mechanism of rubber to thermal effect. The dissipation energy in each piece of the rubber core is calculated to demonstrate the accumulation of energy in rubber bushing. This paper successfully employs multi-body analysis to predict the dissipation energy of rubber components.
- 3D Flexible, Conductive and Wearable Fabric Strain Sensors
Abstract: 3D Flexible, Conductive and Wearable Fabric Strain Sensors
Author Bingang XuJianfeng LiXiaoming TaoHong H
3D fabrics are flexible and wearable substrates for making functional apparels and relevant medical equipments with many distinguished qualities. This paper proposes an easily-fabricated method for 3D fabric pressure sensor based on carbon black coated 3D textile fabrics. The as-made sensor is flexible, conductive and stable even after many times of cyclic compressions. It can measure external pressure ranging from 0 to 33 kPa. During the compression process of the sensor, its electrical resistance would decrease due to conductive structure deformation. The sensor has the potential to transfer pressure information into the change of electrical resistance of the sensor, which is more easily acquirable and readable. This property of the sensor can find promising applications in many fields.
- Stability of Grain Yield of Maize Hybrids in Eight Environments in Mali
Abstract: Stability of Grain Yield of Maize Hybrids in Eight Environments in Mali
Author Coulibaly Mamadou MoryNiaba TemeEssie BlayVernon GracenLate the Charle
Maize is produced in varying environment dictating yield performance and stability in Mali. To validate yield and stability performance, 78 hybrids and 2 checks were tested across eight environments at six sites in Mali during the rainy season of 2011. Two planting dates were used in Sotuba and Siramana locations to create additional environments. The hybrids were evaluated in Randomized Complete Block Design with two replications for one year. The objectives were (1) to study the nature and the magnitude of the genotype x environment interaction and (2) the grain yield stability within and across environments. Sotuba 1, Sotuba 2, Kebila and Kafara were high yielding environments characterized by better performance and very high yield. Siramana 1, Siramana 2, Tamala, and Koulikoro were low yielding environments which was determined with GGE biplot analysis. Nine hybrids were stable across the high yielding environments. Across the low yielding sites, twenty two hybrids exhibited stable performance. Seven Inbred lines showed positive GCA in high yielding environments indicating a predominance of additive gene action. The best SCAs were obtained with P43SRC9FS100-1- 1-8/V481-73, CML442/87036 and (KU1403x1368)/CML505. The hybrid with the best SCA value P43SRC9FS100-1-1- 8/V481-73 was from parents exhibiting the highest GCA values.