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Abstract The beet armyworm, Spodoptera exigua (Hubner) (Lepidoptera: Noctuidae), has become a significant pest of chickpea in recent years. The polyphagous nature allows it to survive on various hosts during the off-season, creating a great menace to the crop in the following season. To assess the incidence and document the alternate hosts of S. exigua, a rapid roving survey was conducted in 11 chickpea-growing areas of Prakasam district, Andhra Pradesh, India. Additionally, the life history traits of S. exigua were studied on major alternate host plants under laboratory conditions (27 ± 1 °C and 70 ± 2% RH) to understand the survival, life expectancy and potential contribution to future populations. The results show that, among the different crops surveyed, the maximum larval incidence was noticed in maize (1.93 larvae/plant), cowpea (1.73 larvae/plant), and sunflower (1.68 larvae/plant) during the off-season. Life history studies of S. exigua showed that highest larval survival percentage was observed on chickpea (83.6%), while the lowest was on maize (44.5%). The mean developmental time for larvae was longest on maize (27.1 days) and shortest on chickpea (14.9 days). Larvae did not develop beyond the third instar when fed with chilli. The growth index statistics showed chickpea (9.2) was the most suitable host plant, whereas maize (0.9) was the least suitable host. The age-stage-specific survival rate (Sxj) varied across developmental stages, and the survival curves overlapped, indicating different growth rates among individuals. The life expectancy (exj) at age zero was highest on groundnut (37.06 days). The intrinsic rate of increase (r) of S. exigua was lowest on maize (0.10 ± 0.0013) and highest on chickpea (0.22 ± 0.0010). Similarly, the net reproductive rate (R0) was highest on chickpea (846.39 ± 18.22) and lowest on maize (59.50 ± 2.06). The population doubled every 3.08 ± 0.011 days on chickpea compared to 7.22 ± 0.80 days on maize. The study conclusively indicates that chickpea and sunflower, primarily cultivated during the rabi season in India, are the most preferred hosts for S. exigua. In contrast, maize and cotton, mainly grown during the kharif season, are less preferred and merely support the pest's survival. Consequently, S. exigua switches hosts between different crops growing seasons, so effective management of S. exigua during the kharif season can help prevent pest outbreaks during the rabi season.

Abstract The present work examines the physical, thermal tensile, and chemical properties of wood skin fibers obtained from second generation Bitter Albizia (BA) tree skin. Chemical characterization of BA fibers showed the presence of various chemical contents such as cellulose of 74.89 wt. %, hemicellulose of 14.50 wt. %, wax of 0.31 wt. %, lignin of 12.8 wt. %, moisture of 11.71 wt. %, and ash of 19.29 wt. %. The density of BA fibers (BAFs) was showed 1285 kg/m3. XRD analysis of BAFs showed a crystallinity index (CI) of 57.20% and size of crystallite of 1.68 nm. Tensile strength and strain to failure of BAFs examined through tensile test were 513–1226 MPa and 0.8–1.37% respectively. TGA portrayed the thermal steadiness of BAFs as 339 °C with 55.295 kJ/mol kinetic activation energy, its residual mass was 23.35% at 548 °C. BAFs with high CI, less wax content, and better tensile strength make more suitable for making polymer matrix composites. SEM images of the BAFs surface depicted that the fiber outer surface has more rough which shows that they can contribute to hige fiber-matrix adhesion during composites preparation.

In recent scenario, women are suffering from breast cancer disease across the world. Mammography is one of the important methods to detect breast cancer early; that to reduce the cost and workload of radiologists. Medical image processing is a tremendous technique used to determine the disease in advance to reduce the risk factor. To predict the disease from 2-D mammography images for diagnosing and detecting based on advanced soft computing paradigm. Still, to get more accuracy in all coordinate axes, 3-D mammography imaging is used to capture depth information from all different angles. After the reconstruction of this process, a better quality of 3D mammography is obtained. It is useful for the experts to identify the disease in well advance. To improve the accuracy of disease findings, deep convolution neural networks (CNN) can be applied for automatic feature learning, and classifier building. This work also presents a comparison of the other state of art methods used in the last decades.

Wireless Sensor Network is easy to configure and deployment of network is also simple. It is very useful in gathering the information. As sensor device are small in size and it is operated by the battery which once die is not rechargeable, so minimizing energy consumption and node death rate is challenging issues in WSN. Once node die it can’t take part in information gathering which is not good for the overall system performance. Making cluster is a way to reduce the energy consumption in WSN by making cluster head which only communicate with base station and rest of the node communicate with cluster head, because distance is major factor for energy consumption in transmission of data. Wireless Sensor Network need more improvement and hence proposed intra and inter-cluster communication with sleep/active rate of node in WSN. Author establish a tradeoff between active node and energy consumption because if more node in sleep state then for achieving the target packet failure probability or error free communication all node take more energy take part in Sub-cluster head communication or more hop-distance communication with more energy. Result in terms of network life time, energy consumption, node decay rate and communication overhead shows that presented work performed well when compare with existing technique.

Abstract Basalt-based natural fiber hybrid composites with fillers are always the most anticipated composite material candidates for lightweight structural applications. Current work focusses on the preparation, characterization and testing of Basalt (B)/Hibiscus vitifolius (HV) based epoxy biocomposites with and without cashew nutshell fillers. Individual fiber reinforced composites (with 40 vol% of fibers) and hybrid composites (with 40 vol% of fibers in the ratio 1:1) filled with 10–30 vol% of fillers were manufactured using compression moulding techniques. The X-ray diffraction spectrum showed the crystal size and crystallinity index for all biocomposites. It showed a monoclinic crystal structure with an irregular surface of the fiber and filler. The FTIR spectrum showed the chemical composition presented in the biocomposites. The presence of filler and fibers was confirmed by different spectral peaks. Hybrid biocomposites were then subjected to mechanical and thermal investigations. The mechanical properties of the biocomposites showed that the tensile, flexural, and impact strength of the biocomposites varies with the concentration of the cashew nutshell filler. The surface morphology of the fractured sample showed the presence of fabric layer, fiber fracture and pull out, and homogenous dispersion of the fillers in the biocomposites. Thermal degradation curves showed that the thermal stability of biocomposites is improved by adding filler up to 20 vol% because the filler acted as a barrier element for the thermal degradation of biocomposites. From the results, it could be understood that these biocomposites find their applications probably in lightweight structures.

Ti-6Al-4 V is an extensively used and highly versatile titanium alloy. It is renowned for its lightweight-to-strength ratio, excellent biocompatibility, and corrosion resistance. The pursuit of advanced materials with enhanced mechanical strength, and wear resistance has led to the exploration of high entropy alloys (HEA) as particle reinforcements. This study combines Ti-6Al-4 V with AlCoCrFeNi HEA at different weight compositions (0 %, 2 %, 4 %, 6 %, 8 %) to create novel composites with tailored properties. The composites were subjected to density, microhardness, tensile, and pin-on-disc tests to evaluate mechanical and tribological properties. Microstructural analysis revealed that microwave sintering has enhanced densification and resulted in uniform dispersion of HEA particles within the Ti-6Al-4 V matrix. The XRD and EBSD analysis revealed the presence of BCC structure in the composite. 8 wt%-AlCoCrFeNi/Ti-6Al-4 V sample exhibited an impressive 81.66 % increase in microhardness and 21.23 % in yield strength, compared to the base sample. Furthermore, noteworthy reductions of 45 % in wear rate and 40 % in coefficient of friction (COF) when subjected to tribological analysis. The worn surface revealed the presence of oxide layer formation at elevated sliding velocity and distance which resulted in reduced wear rate.

A consistent research attempt to develop newer lightweight-high strength materials facilitates the automobile sector to excel in product efficiency. The present research is another endeavour to anchor the automobile industries by exploring novel composite. The different earth elements SiC and Y2O3 are utilised for the hybrid reinforcement of Al 5052 alloy in four different weight proportions. Friction Stir Processing (FSP) is employed to fabricate composites. The microstructure analysis conducted through the optical microscope reveals the formation of fine grain size at the nugget zone. The effect of dynamic recrystallization and particulate strengthening is reflected in the inflated tensile strength of Al-3SiC-1Yo. The microhardness test results manifest the higher hardness at the nugget zone and descending to the Heat Affected Zone (HAZ) through the Thermo Mechanically affected zone (TMAZ). The post-tensile fracture morphological observation through Scanning Electron Microscopy (SEM) explores the particulate strengthening mechanisms offered by the piled-up dislocation densities. The hybrid hard particle inclusion in the matrix helps to achieve 63.87 %, 50 % and 35 % improvement in tensile strength, hardness and impact toughness of SiC and Y2O3 reinforced FSPed Al alloy. Further, a higher level of inclusion of Y2O3 beyond 0.5 % is found to dent the properties due to the agglomeration effect of Y2O3 particles.

Always, the environment in which humans live needs to be saved from various calamities, and one such calamity is usage of petroleum-based products. Petroleum-based products are derived from various synthetic processes that adversely affect the environment. It may not reflect immediately, but it affects in the near future. They are non-environmentally friendly and cannot progress toward the sustainability factor. The alternative to metallic or synthetic fibers is natural fibers that are derived from plant sources. The demerits of using natural fiber is its less strength; however, this strength can be enhanced by incorporating it as a strengthening component in polymer matrix composite (PMC) materials. Still, the major advantage of using metal is its ability to withstand higher temperatures, whereas PMCs fail in these characteristics. The use of nanoparticles as fillers in the natural fiber–reinforced PMCs is a probable solution to the above problem. This review assesses the thermal characteristics of various nanoparticle-filled natural fiber–based polymer composites. It can be seen from most of the research that the filled polymer composites exhibit better thermal behavior compared with non-filled polymer composites. This consolidation would be useful for researchers to further accelerate their research in this domain.

Summary: The main aim of this work is to enhance the wear performance of the direct metal laser sintered (DMLS) alloy 718 by solution treatment aging (STA) method at room temperature (RT) (28°C) and 400°C in dry sliding conditions. The effect of microstructure, phase analysis, and microhardness on the wear behavior and the influence of STA on the specimen at elevated temperatures were studied. The microstructure revealed the presence of melt pool boundary (MPB) in untreated DMLS alloy while recrystallized grains were observed in the STA-treated alloy. The wear results elucidated that STA-treated alloy exhibited better wear resistance than as-built alloy due to high hardness at both conditions. Severe wear loss occurred at high temperatures caused by the delamination of the brittle oxide glazing layer, while oxidation and adhesive wear were the predominant wear mechanisms. Results also portrayed that the test temperature and STA treatment equally influenced the wear behavior of alloy 718.

Material requirements and design optimization are two parallel verticals for the ever-growing material-based demands. The demand for enhanced properties of the materials can be satisfied by developing composite materials. The capability of additive manufacturing (AM) to handle complex geometries with ease has opened many avenues in topological optimization and lightweight structural design. In the current work, the drone frame has been modeled using Fusion 360 software and topological optimization was carried out to obtain a structural design with maximum load-carrying capacity with minimum material. Subsequently, PLA-Zn filament (with an 80:20 ratio) was used to develop composite specimens through the fused deposition modeling (FDM) 3D printing technique. The effect of various infill patterns on the 3D printed PLA-Zn specimens on the mechanical properties such as tensile, compressive, and impact strength and hardness were evaluated. All the tests were carried out as per ASTM standards. The results showed that the infill patterns such as octet and cubic exhibited higher mechanical properties with 0.56 kN tensile strength, 60.58 MPa compressive strength, 4.84 J/cm2 impact strength, and 80 shore D hardness. Subsequently, the drone frame was printed using the topologically optimized model with the infill pattern which exhibited maximum mechanical properties. The drone frame was also tested in real time for its mechanical strength. The topologically optimized 3D-printed drone frame with a cubic infill pattern can be used as a low-cost replacement for the currently used conventional frame.