Improving the capacity,redox activities of Li-ion batteries through Si3N4@MoS2 hetero-structure design

Journal of Materials Science - To develop advanced anode materials for Li-ion batteries (LIB), an extensive research effort is being employed. The effort focuses much on silicon-based anodes due to...     

Investigation of appropriateness of coated steel piston for aluminium alloy piston for small engines

ABSTRACT

Materials substitution is an imperative research area. The aim of this research is cost reduction, improved performance on its physical, chemical or mechanical properties like improved strength, reduced weight or in terms of performances. The objective of this paper is to investigate the possibilities to use the steel piston in place of the aluminium alloy piston for small engine applications like portable generator. Aluminium alloy piston, uncoated steel piston, nickel-coated steel piston and hard chrome-coated steel piston are considered. Steel pistons plated had standard thickness and were physically experimented. The thermal analysis like thermal deformation, total and directional heat flux analysis were carried out in ANSYS software. For the outperformed piston, the CFD analyses on contoured particles were carried out with help of ANSYS Fluent software. The CFD analysis on contoured particles includes the static pressure, velocity as well as directional velocity components and path line of contoured particles.     

Identifying the miRNA Signature Association with Aging-Related Senescence in Glioblastoma

Glioblastoma (GBM) is the most common malignant brain tumor and its malignant phenotypic characteristics are classified as grade IV tumors. Molecular interactions, such as protein–protein, protein–ncRNA, and protein–peptide interactions are crucial to transfer the signaling communications in cellular signaling pathways. Evidences suggest that signaling pathways of stem cells are also activated, which helps the propagation of GBM. Hence, it is important to identify a common signaling pathway that could be visible from multiple GBM gene expression data. microRNA signaling is considered important in GBM signaling, which needs further validation. We performed a high-throughput analysis using micro array expression profiles from 574 samples to explore the role of non-coding RNAs in the disease progression and unique signaling communication in GBM. A series of computational methods involving miRNA expression, gene ontology (GO) based gene enrichment, pathway mapping, and annotation from metabolic pathways databases, and network analysis were used for the analysis. Our study revealed the physiological roles of many known and novel miRNAs in cancer signaling, especially concerning signaling in cancer progression and proliferation. Overall, the results revealed a strong connection with stress induced senescence, significant miRNA targets for cell cycle arrest, and many common signaling pathways to GBM in the network.     

Neurochemicals measured by 1H-MR spectroscopy: putative vulnerability biomarkers for obsessive compulsive disorder

Object

Obsessive compulsive disorder (OCD) is the fourth most common psychiatric disorder characterized by recurrent, intrusive thoughts and repetitive, ritualistic behaviors that are debilitating to the patient. Despite its high prevalence and the attendant morbidity, the pathophysiology of OCD remains unclear. Magnetic resonance spectroscopy (MRS) provides a noninvasive method to characterize the molecular biochemistry that may contribute to the pathophysiology of OCD. This study aimed to identify alterations in neurochemical measures that are specific to OCD using in vivo proton (¹H) MRS of the caudate nucleus, anterior cingulate cortex, and medial thalamus in these patients, and to identify their role as vulnerability markers by comparing them with the healthy first degree relatives of these patients and healthy controls.

Materials and methods

Appropriate psychometric instruments were applied in the study population followed by ¹H- MRS. The absolute neurochemical measures were quantified using a linear combination model.

Results

Significant differences in neurochemical measures were demonstrated in two of the three candidate regions (except the medial thalamus) between the three study groups.

Conclusions

Our results lend support to the neurodegenerative hypothesis of OCD, and also raise the possibility of exploring these neurochemical measures (as measured by MRS) as putative vulnerability biomarkers in OCD that may aid in early identification and devising early prevention or management strategies for the population vulnerable to OCD.     

The influence of bio additive on the compression ignition engine with diesel and Jatropha methyl ester biodiesel

The present experimental investigation evaluates the effects of using blends of diesel fuel with 20% concentration of Methyl Ester of Jatropha biodiesel blended with bio additive. Both the diesel and biodiesel fuel blend was injected at 23° Before Top Dead Centre to the combustion chamber. The experiment was carried out with three different ratios of bio additive. Biodiesel was extracted from Jatropha oil; 20% (B20) concentration is found to be best blend ratio from the earlier experimental study. The bio additive was added to B20MEOJ at various concentrations of 1?ml, 2?ml and 3?ml, respectively. The main objective is to obtain minimum specific fuel consumption, better efficiency and lesser Emission using bio additive blends. The results concluded that full load shows an increase in efficiency when compared with diesel, and highest efficiency is obtained with B20MEOJBA 3?ml bio additive blend. It is noted that there is an increase in thermal efficiency as the blend ratio increases. Biodiesel blend has a performance closer to that of diesel, but emission is reduced in all blends of B20MEOJBA 3?ml compared to that in diesel. Thus the work marks for the suitability of biodiesel blends as an alternate fuel in diesel engines.     

Scheduling of machines and automated guided vehicles in FMS using differential evolution

This paper addresses the problem of simultaneous scheduling of machines and two identical automated guided vehicles (AGVs) in a flexible manufacturing system (FMS). For solving this problem, a new meta-heuristic differential evolution (DE) algorithm is proposed. The problem consists of two interrelated problems, scheduling of machines and scheduling of AGVs. A simultaneous scheduling of these, in order to minimise the makespan will result in a FMS being able to complete all the jobs assigned to it at the earliest time possible, thus saving resources. An increase in the performance of the FMS under consideration would be expected as a result of making the scheduling of AGVs as an integral part of the overall scheduling activity. The algorithm is tested by using problems generated by various researchers and the makespan obtained by the algorithm is compared with that obtained by other researchers and analysed.     

In-situ fabrication of three dimensional nickel nanobeads by electron beam induced transformation

We report an in-situ transmission electron microscope method for the fabrication of three dimensional nickel nanobeads. Conversion of nickel fluoride into a three dimensional porous, partially fluorine depleted aggregate is shown as intermediate state, followed by transformation into metallic beads. The bead size ranges from 10-600 nm and can be controlled via materials thickness and beam intensity. The material is found sensitive for the formation of nickel dots, rings and lines by focused exposure with various beam shapes.     

Electrochemical Behavior of Biomedical Titanium Alloys Coated with Diamond Carbon in Hanks’ Solution

Biomedical implants in the knee and hip are frequent failures because of corrosion and stress on the joints. To solve this important problem, metal implants can be coated with diamond carbon, and this coating plays a critical role in providing an increased resistance to implants toward corrosion. In this study, we have employed diamond carbon coating over Ti-6Al-4V and Ti-13Nb-13Zr alloys using hot filament chemical vapor deposition method which is well-established coating process that significantly improves the resistance toward corrosion, wears and hardness. The diamond carbon-coated Ti-13Nb-13Zr alloy showed an increased microhardness in the range of 850 HV. Electrochemical impedance spectroscopy and polarization studies in SBF solution (simulated body fluid solution) were carried out to understand the in vitro behavior of uncoated as well as coated titanium alloys. The experimental results showed that the corrosion resistance of Ti-13Nb-13Zr alloy is relatively higher when compared with diamond carbon-coated Ti-6Al-4V alloys due to the presence of β phase in the Ti-13Nb-13Zr alloy. Electrochemical impedance results showed that the diamond carbon-coated alloys behave as an ideal capacitor in the body fluid solution. Moreover, the stability in mechanical properties during the corrosion process was maintained for diamond carbon-coated titanium alloys.     

Effect of interfacial contact forces in single layer cable assemblies

The mechanical behaviour of cables and ropes used in engineering applications, though studied for the past three decades, varies widely depending on the numerical models adopted. Though these models predict the global response reasonably well, they differ widely in modelling the local contact conditions, the frictional effects at the interfaces and predicting the loss of stiffness of the cable assemblies. Three modes of contact can exist among the wires in a stranded cable assembly, i.e. the contact among the wires in the same layer (known as hoop or lateral contact), the contact among the wires in adjoining layers (radial contact) and the combined contact of all the wires (combined lateral and radial contact). The cables are hitherto modelled on the assumption of the presence of one of the contact modes only, though in reality the contact of modes change from one to the other, depending on the loading and the nature of contraction of the wires. The behaviour of the cable can be well understood if the appropriate mode of contact prevalent at every stage of loading is adopted in the model. This paper analyses the contact modes present in a single layer cable assembly and considers its response under an axial tensile load and an axial twisting moment. Based on the initial geometry, the contact mode is determined and depending on successive loading, the contraction of all the wires in the radial and lateral directions are ascertained and the threshold limits at which the contact modes change from one to the other are established. The overall response of the cables under the cascading effects of the presence of different contact modes, is compared with the works of the other authors who have adopted one type of contact mode only during their study. This has resulted in an overall reduction in the stiffness of the cable assembly, compared to the existing models. The force and moments in the individual wires are studied and the contact forces and the resulting contact stresses are established as a function of applied loads. The effect of the friction and the associated slip of the wires have been included. Apart from consideration of the radial contraction of the wires due to the Poisson effect, as accounted by few authors, this paper considers the radial deformation due to contact forces, as a special feature. This has resulted in refined expressions for the curvatures and twist of the wire and the associated forces in the normal and binormal directions. The predictions with these inclusions are compared with the existing works and the importance of the refinements to the cable designers are highlighted.