Enhanced interlaminar shear and impact performance of woven carbon/epoxy composites interleaved with needle punched high performance polyethylene fiber nonwoven

In this study, high-performance polyethylene (HPPE) fiber-based needle punched nonwovens were interleaved in cross-plied woven carbon fabric/epoxy composite laminates to enhance their interlaminar and impact properties. The placement of needle punched nonwoven interleaves exhibited considerable enhancement in interlaminar shear strength (ILSS), impact damage tolerance, and compression after impact (CAI) strength of laminates as evidenced by higher interlaminar strength, less absorbed energy, higher elastic energy, reduced damage degree, reduced out-of-plane deformation, higher load-bearing capacity, and higher residual compressive strength as compared to control sample. In particular, the composite laminate with placement of interleaves in alternating sequence between carbon plies resulted in 205.76% increase in ILSS and 129, 103 and 85% increase in CAI at 10, 25, and 40 J impact energy, respectively. Moreover, damaged surface area and out-of-plane deformation reduced to 38.75% and 62.5%, respectively for the same specimen impacted at 40 J energy. These results suggest that the HPPE fiber-based needle punched nonwoven interleaving can be adopted as a simple and low-cost approach compared with other interleaving techniques, to enhance the resistance to delamination, impact performance, and damage tolerance of traditional structural laminates.     

The role of surface micro-cracks in cementitious materials responsible for the Pickett effect

Mechanics of Time-Dependent Materials - The Pickett theory for the development of drying creep has been discussed by many authors to explain creep-induced shrinkage strains and the development of...     

Impact of ceria over WO3–ZrO2 supported Ni catalyst towards hydrogen production through dry reforming of methane

ZrO₂ supported Nickel catalyst, 9 wt%WO₃ -91 wt%ZrO₂ supported Nickel catalyst and ceria promoted 9 wt%WO₃-91 wt%ZrO₂ supported Nickel catalyst (5NixCe/WZr catalyst) is synthesized via wet impregnation and characterized by XRD, UV–vis, CO₂ -TPD, H₂ TPR-CO₂ TPD-H₂ TPR cycle, TPH, TPH followed by O₂ -TPO and CO₂ -TPD followed by O₂ -TPO. Due to limitation in surface re-oxidizing capability and shading of catalytic active sites by thermally stable carbonates; catalytic activity of unpromoted catalyst system is less. 5NixCe/WZr catalyst has extended CH₄ decomposition sites, additional basic sites (during the reaction) for CO₂ adsorption and excellent redox accompany (Ce ⁺⁴/Ce ⁺³, W+⁶/W ⁺⁴) for carbon oxidation and re-oxidizing capability of surface up to the pristine level. 2.5 wt% Ceria promotional addition is resulted into 78% H₂ yield constantly up to 420 min TOS. The carbon deposit over ceria promoted system (up to 2.5 wt%) is amorphous type, more easily/moderately reducible, oxidizable and removable.     

Rice bran nutraceutics: A comprehensive review

Agro-industry yields ample quantity of several byproducts with considerable importance. These byproducts are mostly under-utilized, often used as animal feed or rejected as waste; hence their true potential is not harnessed. The use of such superfluous resources is of not only economic significance but also a form of commercial recycling. Rice bran is an important byproduct of rice milling industry with a global potential of 29.3 million tons annually. It is gaining great attention of the researchers due to its nutrient-rich composition, easy availability, low cost, high antioxidant potential, and promising effects against several metabolic ailments. Bioactive components of rice bran, mainly γ-oryzanol, have been reported to possess antioxidant, anti-inflammatory, hypocholesterolemic, anti-diabetic, and anti-cancer activities. Rice bran oil contains appreciable quantities of bioactive components and has attained the status of “Heart oil” due to its cardiac-friendly chemical profile. Nutraceutics have successfully been extracted from rice bran using several extraction techniques such as solvent extraction, supercritical fluid extraction, microwave-, and ultrasonic-assisted extraction. Current paper is an attempt to highlight bioactive moieties of rice bran along with their extraction technologies and health benefits.     

Evaluation of multiple satellite rainfall products over the rugged topography of the Tekeze-Atbara basin in Ethiopia

Satellite rainfall products are an important source of rainfall data in un-gauged catchments. However, these products need to be validated as their accuracy can be affected by geographical position, topography, climate and embedded algorithms. Eight satellite rainfall products such as African Rainfall Climatology (ARC2), Climate Hazards Group InfraRed Precipitation with Stations (CHIRPs), Global Precipitation Climatology Project GPCP), CPC Morphic technique (CMorph), Atmospheric Administration Climate Prediction Center (NOAA-CPC) merged analysis (CMap), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), African Rainfall Estimation Algorithm version 2 (RFEv2) and Tropical Rainfall Measurement Mission (TRMM) were evaluated against ground observations over the complex topography of the upper Tekeze-Atbara basin in Ethiopia. The accuracy of the datasets was evaluated at different temporal and larger spatial scales over the period 2002–2015. The results show that the rainfall data of CHIRPS outperformed all other products at all temporal and spatial scales. Next to CHIRPS, estimates from RFEv2, 3B42v7, and PERSIANN products are closest to the measurements at rain gauges for all spatiotemporal scales: daily, monthly and seasonal, and both at point and spatial scales. The percentage bias (PBias) and correlation coefficient (r) of these products were within ±25% and >0.5 for all scales. The remaining products performed poorly with PBias up to 200% and lower r (<0.5) at all scales. However, the performance of all products improved as the temporal scale increased to month and season at all spatial scales. Compared to low altitudes <2000 m above sea level (m.a.s.l.), the PBias at high altitude (>3000 m.a.s.l.) increased by 35% whilst r dropped by 28%. CHIRPS and 3B42v7 products showed best agreement in mountainous terrains. However, all datasets show no consistency of the error sign. CMorph and 3B42v7 consistently overestimate rainfall relative to all rain gauges during the pixel-to-point rainfall comparison approach and at lowland areas during the areal averaged rainfall comparison. The other six products showed a clear underestimation at all spatial scales. In summary, the results show that rainfall estimates by CHIRPS, RFEv2 and 3B42v7 have a consistently better agreement with ground rainfall at all spatiotemporal scales. Considering the complex topography and limited gauges, the performance of CHIRPS, RFEv2 and 3B42v7 indicates that these products can be used for hydrological and overall water management applications in the region.     

A Study on Thermal Response of Nanoparticles in External Magnetic Field

Journal of Superconductivity and Novel Magnetism - Hyperthermia has become an important area of research for cancer treatment throughout the world. Choosing appropriate magnetic nanoparticles for...     

Prediction of Time Series Empowered with a Novel SREKRLS Algorithm

For the unforced dynamical non-linear statespace model, a new Q1 and efficient square root extended kernel recursive least square estimation algorithm is developed in this article. The proposed algorithm lends itself towards the parallel implementation as in the FPGA systems. With the help of an ortho-normal triangularization method, which relies on numerically stable givens rotation, matrix inversion causes a computational burden, is reduced. Matrix computation possesses many excellent numerical properties such as singularity, symmetry, skew symmetry, and triangularity is achieved by using this algorithm. The proposed method is validated for the prediction of stationary and non-stationary MackeyGlass Time Series, along with that a component in the x-direction of the Lorenz Times Series is also predicted to illustrate its usefulness. By the learning curves regarding mean square error (MSE) are witnessed for demonstration with prediction performance of the proposed algorithm from where it’s concluded that the proposed algorithm performs better than EKRLS. This new SREKRLS based design positively offers an innovative era towards non-linear systolic arrays, which is efficient in developing very-large-scale integration (VLSI) applications with non-linear input data. Multiple experiments are carried out to validate the reliability, effectiveness, and applicability of the proposed algorithm and with different noise levels compared to the Extended kernel recursive least-squares (EKRLS) algorithm.     

Joining and testing of alumina fibre reinforced YAG-ZrO2 matrix composites

Alumina (Nextel? 610) fibre reinforced YAG-ZrO₂ matrix composites were successfully joined by using different brazing alloys, metallic interlayers and a glass-ceramic. All joints were mechanically stable and free of cracks. Three commercial brazing alloys and a new alloy based on Ti/Cu/Al interlayers were selected to join these composites for applications in a non-oxidizing environment. A glass-ceramic based on SiO₂-Al₂O₃-CaO-MgO was developed in case the joined component needs to be oxidation resistant. To evaluate the thermal stability, all joined composites were aged up to 100 h in air at 550 °C for brazing joints or 850 °C and 930 °C for glass-ceramic joints. The mechanical strength was measured using single lap and four point bending tests before and after ageing. Four point bending tests on glass-ceramic joined samples showed an average joint strength of about 70 MPa which is 35% of as-received composites.     

Silicon Coating on Maize Seed Mitigates Saline Stress in Yermosols of Southern Punjab

Silicon - Silicon (Si) has been identified as a key nutrient in plants to lower the pressures of environmental stress. In pot experiment, seeds of different maize hybrids (Pioneer-1543,...