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Chemically treated short cellulosic fibers (jute and sisal) reinforced heat-treated silanized fly ash-dispersed hybrid polymer composites were synthesized by a compression molding technique. The 35 wt.% filler loading unsaturated polyester matrix-based composites were fabricated. The mechanical behavior of the unsaturated polyester matrix and unsaturated polyester-based composites was successfully assessed at the sub-micron length scale using the nanoindentation or depth-sensing instrumented indentation technique. It was observed that along with filler addition, the mechanical properties at the sub-micron scale improved significantly. A successful attempt to investigate the effect of filler inclusion within the unsaturated polyester matrix through various nanoindentation-derived parameters, namely, nanohardness, reduced modulus, elastic recovery, residual depth, wear rate as well the dynamic mechanical properties was also executed in the current investigation. [ABSTRACT FROM AUTHOR]

Alkali treated (5 wt. % alkali was used on the total weight of the alkali solution and the treatment time was 2 h) discontinuous cellulosic fiber (jute and sisal were used as cellulosic fibers and 35 wt. % filler content was incorporated) reinforced chemically modified ZrO2 (ZrO2 was used as 10 wt. % of total filler content. In this context, it is worthwhile to mention that when both fillers were used, the fiber content was taken in the weight ratio of 1:1.) dispersed hybrid unsaturated polyester composites were fabricated by a compression molding technique. The mechanical behavior of the fabricated composites was evaluated at the sub-micron scale by nanoindentation (indentation with an applied load on the composites surface at the nano-metric range) or depth-sensing instrumented indentation technique. The significant effect of incorporation of the dispersing phases within the unsaturated polyester matrix with respect to mechanical properties at microstructural length scale was observed. A marked improvement in the nanoindentation-derived parameters viz., nanohardness, reduced modulus, elastic recovery, and indentation creep was observed which may be attributed due to the influence of fillers inclusion within the unsaturated polyester matrix. An extensive effort was laid to analyze the dynamic mechanical properties using the sinus indentation mode associated with nanoindentation measurements to further correlate the influence of fillers addition with the indentation-derived parameters. [ABSTRACT FROM AUTHOR]

Alkali-treated sisal fibre-incorporated silanized ZrO2 dispersed unsaturated polyester composites were fabricated with a filler loading of 5, 15, 25, 35, 45 wt%, respectively. The mechanical characterization of the composites was suitably executed at the sub-micron scale using the nanoindentation technique. Various mechanical properties were derived from the standard nanoindentation measurements namely, nanohardness, reduced modulus, recovery index, residual depth, wear rate and indentation creep, respectively. A marked improvement in the mechanical properties of the unsaturated polyester matrix due to the incorporation of the fillers (sisal and/or ZrO2) was observed through indentation-derived parameters namely, nanohardness (∼186%), reduced modulus (∼175%), recovery index (∼62%), wear rate (∼63%) and indentation creep (∼33%), respectively. A simulated dynamic mechanical analysis was performed using the sinus mode of the nanoindentation technique. A similar enhancement in the dynamic mechanical properties of the matrix was further observed through dynamic mechanical analysis as storage modulus (∼71%), loss modulus (∼60%), loss factor (∼150%) and specific damping coefficient (∼200%), respectively. [ABSTRACT FROM AUTHOR]

Alkali treated jute fibre incorporated silanized ZrO2 based unsaturated polyester composites were synthesized using compression moulding technique. The filler loading was adopted with a progressive wt. %, of 5, 15, 25, 35 and 45 respectively. These samples were further subjected to structural investigation using scanning electron microscope and X-ray diffraction technique to observe the morphological features and crystalline nature of the matrix. The mechanical characterization was accomplished at the microstructural length scale from macro to submicron range. It was observed that the composite with 35 wt. % filler loading resulted in the best properties among the lot. [ABSTRACT FROM AUTHOR]

National cardiac life support training program initiated in October 2016, it is a systematic approach to management of a victim of cardiac arrest. The program aimed to address the training needs of a junior physician such as the one undergoing postgraduate medical education and other health-care professionals. It is a 2-day "hands-on" course that recommends an instructor-candidate ratio of 1:6 and limits the number of candidates to 30 per session to maintain adequate mentee-mentor interaction, monitoring, and evaluation. This program is developed in collaboration with Society for Emergency Medicine in India, Indian College of Anesthesiologists, Indian College of Cardiology, and Association of Healthcare Providers India. In addition, this program has been endorsed by West Bengal University and National Board of Examinations, New Delhi. Currently, The Simulation Society which deals with online teaching simulation has lent its support by endorsing this program. [ABSTRACT FROM AUTHOR]

Hydrothermally synthesized undoped and Sr-doped hydroxyapatite-dispersed polyether ether ketone composites has been fabricated by using hot isostatic pressing technique with 5, 10, 15, and 20 wt.% as the dispersoids content. The detailed structural investigation of the fabricated composites has been performed by scanning electron microscope, high-resolution transmission electron microscope, and X-ray diffraction technique that confirmed the uniform dispersion of the dispersoids with the polyether ether ketone matrix. The microindentation measurements show that the mechanical properties of the polyether ether ketone matrix improved remarkably with incorporation of the hydroxyapatite (HAp) particles. The nondestructively evaluated elastic modulus so obtained for the matrix and composites were further validated through finite element analysis. Moreover, the in vitro cytotoxic of the fabricated nanocomposites were also evaluated to assess its potential as a bioactive material. [ABSTRACT FROM AUTHOR]

Sisal fiber along with ZrO2 particles dispersed unsaturated polyester (UP) composites were fabricated by compression molding technique. The filler contents were varied from 5 to 45 wt% with a gradual increase of 10%. The structural investigation was done using Scanning electron microscopy, X‐ray diffraction, and Fourier transform infrared spectroscopy. Mechanical testing was performed through microhardness tester, tensile, flexural, and Izod impact test. The optimum mechanical properties were obtained at 35 wt% of filler incorporation within UP matrix followed by a slight deterioration at 45 wt%. Fractographic images of the composites display the phenomena of fiber pull‐out, debonding and breakage. The water absorption test was performed both at room temperature and boiling water temperature conditions. The thermal insulation measurement was performed by Kawabata method. POLYM. COMPOS., 40:2790–2801, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Jute fiber along with Cu particle dispersed unsaturated polyester composites having different filler (both Jute and Cu were in equal wt%) loading viz. 2, 5, 10, and 15 wt% were fabricated by compression molding technique. In the present investigation, it is observed that with fillers (Jute and Cu) incorporation the microhardness increases and reaches its maximum at 10 wt% of fillers content followed by slight deterioration at 15 wt%. Structural investigation through X‐ray diffraction, Fourier transforms infrared spectroscopy, and scanning electron microscopy confirms the presence and dispersion of filler. It is observed that with filler addition the crystallinity (%) of the matrix increases which is obtained from X‐ray diffraction pattern. Fourier transform infrared spectroscopy ensured the bonding of fillers with the matrix and detected the presence of moisture. The mechanical testing viz., tensile, flexural, and Izod impact test shows the strength and modulus increase monotonically upto 10 wt% filler addition followed by slight decreases at 15 wt% filler content. The scratch result shows the optimization of strength and toughness of the composites. Thermo‐gravimetric analysis and differential thermo‐gravimetric analysis showed that the thermal stability, degradation temperature, and residual mass significantly increased with fillers addition. The water absorption test (room temperature and boiling temperature) predict a variation in weight with time. POLYM. COMPOS., 39:E1315–E1330, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract: Jute fiber along with Al particle‐reinforced unsaturated polyester composites having different filler (Jute and Al) loading viz. 2, 5, 10, and 15 wt.% were fabricated by compression molding technique. In the present investigation, it was observed that with fillers incorporation, the microhardness increases and becomes optimum at 10 wt.% filler content followed by slight deterioration at 15 wt.%. Scanning electron microscopy confirms the dispersion of the fillers. An improvement of crystallinity with filler addition was observed from X‐ray diffraction pattern. Fourier transform infrared spectroscopy pattern ensured the bonding between filler and matrix. Flexural and Izod impact tests show that the strength and modulus increase monotonically up to 10 wt.% filler addition followed by slight decreases at 15 wt.%. Thermogravimetric analysis and Differential Thermogravimetric analysis show that the thermal stability, degradation temperature, and residual mass significantly increase with fillers addition. The thermal insulation of the composites decreases, whereas the electrical conductivity of the composites increases with the addition of the filler. The water absorption at room and boiling temperature suggests swelling and deterioration in strength of the swelled composites. [ABSTRACT FROM AUTHOR]

Enhancement in toughness without reducing its mechanical property is a serious issue in context of application of the biocomposites. Therefore, in this study, the effect of incorporation of Al2O3 and ZrO2 particles in the polymer matrix on the mechanical properties of jute fiber reinforced unsaturated polyester biocomposites were investigated. Reinforcements with fibers were carried out in different weight proportions (5–25%) and with varied fiber lengths. The biocomposites were fabricated using hand lay‐up method. Overall 20 wt % filler content (18 wt% fiber and 2 wt% metal oxide particles) was selected as the optimized composition. The fibers were treated with NaOH solution for better compatibility with matrix whereas the particles were treated with silane for better adherence with the matrix. Microhardness, tensile, flexural, and impact properties of the biocomposites were evaluated as per standard. Fractography of the biocomposites were done using scanning electron microscope. It was found that the ZrO2 particle incorporated bicomposites show better mechanical properties than the Al2O3 dispersed bicomposites. POLYM. COMPOS., 39:E101–E112, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]