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Energy harvesting of PZT/PMMA composite flexible films
No full textPolymer/lead zirconate titanate {[Pb(Zrx, Ti1-x)O3], PZT, x = 0.40} flexible composite films are prepared by solvent evaporation technique. Carbon tape used as a top and bottom electrodes for fabricating flexible PZT composite films. The phase purity and functional groups of PZT and polymer humps are confirmed by XRD and FTIR respectively. XPS analysis showed that PMMA contains carbon (C) and oxygen (O). Carbon (C), oxygen (O), lead (Pb), zirconium (Zr) and titanium (Ti) are present in PZT/PMMA composite films. The chemical states of Pb, Zr and Ti ions are 2+, 4+ and 4+ respectively confirmed by XPS. The higher forefinger bending motion of the film is found to reveal greater output voltage (5.2 V) than the output voltage (1.6 V) for slight bending motion of the forefinger. Therefore, based on the results human mechanical forces induce compressive stress on PZTs ferroelectric based composite films and are excellent candidate for energy harvester
Design and development of polybenzoxazine�POSS hybrid materials from renewable starting materials for low k and low surface free energy applications
No full textAbstract
The introduction of nano-sized polyhedral oligomeric silsesquioxane (POSS) derivatives into polymer matrices have received significant interest in recent years mainly because of the inherent properties of
POSS which include low coefficient thermal expansion, low density, low thermal conductivity, low dielectric constant, high oxidation resistance, and low surface free energy. In view of this, an attempt
has been made to develop thermally stable, flame retardant, low dielectric, and lower surface free energy polybenzoxazine-POSS (PBz-POSS) hybrid prepared using renewable agro-waste (cardanol,
furfurylamine and stearylamine) as starting materials. A new approach involving thiol-ene click reaction has been adopted to introduce mercapto functional POSS (SH-POSS) into cardanol
benzoxazines(Bz-C-F and Bz-C-S). The thermal, dielectric, flame-retardant, and contact angle studies of the prepared PBz-POSS hybrids were investigated using modern characterization techniques. The results from thermal, flame, dielectric and water contact angle studies clearly indicate that the developed renewable, cost-effective and eco-friendly PBz-POSS hybrid materials can be exploited as coatings and sealants as well as for low dielectric microelectronic applications to substitute the currently used petroleum-based raw material
Phosphorene: Current status, challenges and opportunities
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The field of 2-dimensional (2D) materials has
witnessed a sharp growth since its inception and can
majorly be attributed to the substantial technical and
scientific developments, leading to significant improve�ments in their syntheses, characterization and applications.
In the list of 2D materials, the relatively newer addition is
phosphorene, which ideally consists of a single layer of
black phosphorous. Keeping in mind the past, and ongoing
research activities, this short account offers a brief
overview of the present status and the associated
challenges in the field of phosphorene-related research,
with special emphasis on their syntheses, properties,
applications and future opportunitie
Experimental studies of machining parameters on surface roughness, flank wear, cutting forces and work piece vibration in boring of AISI 4340 steels: modeling and optimization approach
No full textThe statistical mathematical models are developed to investigate the infuence of cutting parameters on surface roughness, tool wear, cutting force, tangential force and the work piece vibration in boring of AISI 4340 steels. A full factorial
design of experiments is used to conduct 27 experiments on AISI 4340 as the work piece material and TiCN–Al2O3–TiN
multi-layered coated carbide inserts. Online data acquisition of cutting forces on the cutting tool and the work piece
vibrations are measured by using piezo-electric dynamometer and laser Doppler vibrometer, respectively. This paper
proposes optimization method using grey relational analysis (GRA) and predictive models like support vector machine
and response surface method are used to predict the GRG values and optimize the machining parameters. The GRA is
used for converting multi response optimization problem into optimization of single objective of grey relational grade
(GRG). Finally confrmation test was performed and also optimized the machining parameters to minimize the surface
roughness (Ra), tool wear (VB), cutting force (Fx), tangential force (Fz) and work piece vibration (VA
Bio-inspired Weighed Quantum Particle Swarm Optimization and Smooth Support Vector Machine ensembles for identification of abnormalities in medical data,
No full textKnowledge mining is an emerging feld where various patterns, rules, etc. can be generated which helps us in the analysis of the result. Medical information systems in modern hospitals and medical institutions become larger and larger, it causes great difculties in extracting useful information for decision support. Especially, when traditional manual data analysis has become inefcient and methods for efcient computer-based analysis are indispensable. Decision support system is a suitable tool for medical application which helps in the extraction of useful data. A new hybrid model, weighted-quantum particle swarm optimization (WQPSO) for data clustering in sequence with smooth support vector machine (SSVM) is proposed for classifcation. The parameters considered to evaluate the clustering methods are intercluster distance, intra-cluster distance, and validation index. Experiments are performed in MATLAB and the performance analysis, comparisons are made with real-world datasets that are retrieved from UC Irvine Machine Learning Repository. The proposed approach overcomes the drawbacks of existing algorithms in terms of accuracy, performance and complexity. To validate the proposed algorithm, experiments are conducted on two data sets, i.e., liver disorders dataset and Wisconsin Breast Cancer Diagnosis (WBCD) dataset. The accuracy of proposed WQPSO-SSVM classifcation methodology is 83.76% for liver disorder, 98.42% for WBCD, 95.21% of mammography mass data. Among the considered algorithms such as WPSO-SVM, fuzzy, K-means, and fuzzy C-means methods, WQPSO-SSVM is found to yield a better convergence and provide an improved optimal solutio
Development and characterization of chicken feather rachis, sawdust and HDPE hybrid composite material
No full textThis paper presents the properties of the high- density polyethylene based hybrid composite made with two natural fibers: chicken feather and sawdust. The composites were
produced and fabricated with the aid of two processes they are extrusion and injection molding. These composites were produced with different chicken feather and sawdust ratios
(80H-10CF-10SD, 80H-5CF-15SD, and 80H-15CF-5SD). Tensile and Flexural tests were performed using a Universal Testing Machine (UTM) and impact strength was tested with
notched Izod impact test method. Results showed that there is an improvement in the different mechanical properties such as tensile, flexural and impact strength because of the addition of
chicken feather and sawdust
Novel Z-scheme composite Ag2CrO4/NG/polyimide as high performance nano catalyst for photoreduction of CO2: Design, fabrication, characterization and mechanism
No full textThe evolution of new Z-scheme composites aids to solve the increasing energy demand via artificial photosynthesis.
This research introduced novel Z-scheme nanocomposite, Ag2CrO4/nitrogen-doped graphene /Polyimide
(Ag2CrO4/NG/PI), and its photocatalytic activity in CO2 reduction under simulated sunlight irradiation. The
nanocomposite was prepared with ultrasound-assisted in-situ deposition of different amounts of Ag2CrO4-NPs on NG/
PI and completely characterized using various techniques such as AFM, FE-SEM, XPS, XRD, FT-IR, DRS and PL
which confirmed the presence of Ag2CrO4, NG and PI in the composite structure. The photocatalytic investigations
showed a significant promotion for light absorption ability of Ag2CrO4 on NG and PI. The high performance
photocatalytic activity of Ag2CrO4/NG/PI can be interpreted by the gap of EHPs in the photocatalyst as a Z-scheme
due to the construction of hetero-linkage structure between Ag2CrO4 and PI. Meanwhile, the presence of the pyridinic
N as an unique selective site toward CO generation, can reduce the free energy barrier for the potential-limiting step
to compose important intermediates which lead to high-efficiency photocatalyst activity. The optimal Ag2CrO4/NG/PI
(25AN) photocatalyst presented a CO2 photoreduction rate of 352.1 μmol·h-1 ·gcat -1 , which was higher than previously reported works under similar condition. This investigation introduces a novel photocatalyst nanocomposite
of the, Ag2CrO4/NG/PI, in concurrent natural resources conservation and green productivit
OPTIMIZATION OF PROCESS PARAMETERS IN REMOVAL OF LEAD FROM AQUEOUS SOLUTION THROUGH RESPONSE SURFACE METHODOLOGY
No full textThis article investigation was done on removal of lead from aqueous solution onto Tamarind fruit shell powder (Tamarinus Indica. L), a biosorbent of a low cost, easily available, agricultural waste using biosorption. The optimum operating parameters like agitation time, biosorbent dose, initial lead concentration, and pH have been studied with batch process and validated by Response Surface Methodology. The maximum percentage removal of lead is 83.5 at optimum conditions of agitation time is 33.11 min, biosorbent dosage is 0.99 g, initial ion concentration is 26.44 mg/l and pH is 6.98 using RSM. The experimental data were evaluated using adsorption isotherms. The given data are best suited to Freundlich model. Kinetic and thermodynamic data were tested with pseudo-first-order and pseudo-second-order models and well correlated to pseudo-second order equation. The results revealed that Tamarindus Indica. L was a favorable biosorbent to remove lead and zinc
Effect of graphene oxide on microstructure and strengthened properties of fly ash and silica fume based cement composites
No full textNow a day’s utilization of nano materials have been increased for enhancing the ultrahigh performance cementitious composites. Accordingly, graphene oxide (GO) was found as one of the nanomaterials, which represents an unprecedented range properties with a potential to enhance the strength and toughness of cement based composites. GO is also an appropriate material to react with binder particles as it
consists a range of reactive oxygen operational chemical groups. This paper investigates the effect of graphene oxide (GO) on microstructure and strengthened properties of fly ash and silica fume based cement composites, by determining the characteristics of cement composites through mechanical and micro structural studies (SEM and XRD analysis). The Scanning Electron Microscope (SEM) images exhibited that, graphene oxide (GO) converted the structural nature of cement composite from a porous nature to a considerably pore filled nature with the improved mechanical properties. XRD technique was
assisted in identifying the crystalline materials and studying the phase composition of cement composites. This significant extensive research provides a new pathway for achieving high performance cement composites
Novel 1,3,4-Thiadiazole Linked Amide Derivatives of Pteridone: Synthesis and Study of Anticancer Activities
No full textCancer is a second leading cause of death after heart attack, in developing as well as undeveloped countries. It is caused by unregulated growth and metastasis of the abnormal cancer cells. Cancer can be cured by radiation, immunotherapy and chemotherapy, among them; chemotherapy is a good treatment for cancer, in which chemotherapeutic drug is used. The anticancer activity of newly synthesized compounds (13a-j) was carried out on four different types of human cancer cell lines like MCF-7 (breast), A549 (lung), Colo-205 (colon) and A2780 (ovarian) by the MTT method, and compared to etoposide used as a positive control. Among them, compound 13g with electron-withdrawing (3,5-dinitro) group, exhibited more promising activity in all cell lines (MCF-7 = 0.10±0.076 µM, A549 = 0.17±0.039 µM, Colo-205= 0.13±0.022 µM and A2780 = 0.87±0.027µM). This compound may act as lead drug in cancer chemotherapy. In future, this compound can be examined for clinical studies