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In the present research, glass and basalt fiber-reinforced polypropylene composites' behaviour in quasi-static and dynamic conditions is studied. Composites were fabricated by vacuum assisted Compression molding method. Composites failure under quasi-static tension and compressive conditions was studied along with its failure behaviour under low-velocity impact and super-sonic shock loading under dynamic conditions. The study results showed that basalt fiber-reinforced polypropylene (Basalt/PP) composite's tensile and compressive strength is higher than glass fiber-reinforced polypropylene (Glass/PP). The Basalt/PP showed no penetration against low velocity impact (LVI) with negligible deformations till 50 J. However, the Glass/PP perforated at 50 J with various failure patterns occurring at back side. The fiber-matrix interface adhesion plays an important role in super-sonic shock loading by absorbing shock wave energy due to ductile nature of polypropylene and the two composites absorbed energy via matrix and fibers failure, no brittle failure of laminates occurred under shock loading. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the performance of thirty-six Basmati rice genotypes for yield and its related traits under direct-seeded rice (DSR), system of rice intensification (SRI), chemical-free cultivation (CFC), and conventional transplanted rice (TPR).The genotypes were evaluated for two years at two locations in randomized block design with three replications. Genotype Pusa Basmati 1121 scored highest ~22% yield increase in system of rice intensification method over transplanted rice followed by Pusa Basmati 1 (~20%) genotypes HKR 11-447 (~18 %). Genotype Pusa Basmati 1, Pusa Basmati 1637-2-8-20-5 and Pusa Basmati1734-8-3-85 produced 8-16 % higher yield in chemical-free cultivation in comparison to TPR. Genotypes HKR 98-476, CSR 30, PAU 6297-1 yielded equally in DSR as well as in TPR. All the genotypes under study showed earlier flowering and maturity in DSR followed by SRI and TPR=CFC. Pusa Basmati 1509recordedthe earliest flowering across the environments. Most of the genotypes showed an increase in panicle weight, number of tillers per plant, number of spikelets per panicle, percent filled spikelets, Biological yield, and grain yield under SRI over other methods of rice crop establishment. Among different methods, SRI was found best than TPR, CFC, and DSR (wet). [ABSTRACT FROM AUTHOR]

Urbanization and industrialization enhance the degradation of the groundwater quality due to the discharge of domestic and industrial effluents in the aquatic bodies or on the surface of ground either in treated or untreated form. Therefore, the present study was carried out to assess the groundwater quality at the Laksar block of district Haridwar in Uttarakhand. Groundwater samples (SS-1-10) were collected from the hand pumps of the study area. The sampling site (SS-1) was taken as control. The distance of all sampling sites from control site ranged from 6.3Km to 18.3Km. The samples were analyzed for various physicochemical parameters viz Temperature, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Solids (TS), pH, Dissolved Oxygen (DO), Total Hardness (TH), Calcium Hardness (CaH), Chloride (Cl), Sulphate (SO4 --), Nitrate (NO3 ---), Acidity, and Iron (Fe) for two years (2017 to 2019). The data obtained after analysis was simplified using Water quality index (WQI). The maximum concentration of TDS, TS, TH, CaH, and Fe was observed at SS-6 that may be due to the direct industrial discharge of Sugar mill effluent on the ground. Based on WQI value, SS-6 (WQI value-150.27) was found most polluted site. Hardness was found above the standard limit (250mg/l) at SS-6 to SS-10. The Fe was also found above the standard limit of WHO and BIS (0.3mg/l) at SS-6 to SS-10. The study may be useful for managing the groundwater quality of the study area. [ABSTRACT FROM AUTHOR]

• High hardness steel (HHS) sheet with UHMWPE composite backing were tested against a hardened steel core projectile. • The projectile core was eroded by the HHS sheet and stopped in UHMWPE composite. • It is observed that only a core eroded to a certain length and weight by armor system can be defeated. • In numerical modeling core failure strain was determined from the residual weight of cores. • The numerical model can be used to evolve armor design. Thin high hardness steel sheets can be an alternative to expensive ceramic armor systems designed to defeat hardened core projectiles. A thin high hardness steel sheet backed with UHMWPE fiber-reinforced composite was ballistically tested against a 7.62 × 39 mm hardened steel core projectile in a single-stage gas gun. Thin steel sheets of 530 BHN hardness were adhesively bonded with UHMWPE fiber-reinforced composite to fabricate armor plates. Armor plates were able to defeat the projectile showing considerable potential. Tensile strength of steel sheet and UHMWPE-fiber reinforced ply was also determined. A detailed numerical simulation of the impact event was also performed to understand the phenomenon of defeat and penetration in greater detail. The numerical model was calibrated from the recovered projectile's core after the ballistic test. [ABSTRACT FROM AUTHOR]

Material systems capable of handling both the ballistic impact and blast waves are necessary for security forces. In this study, the high strain rate performance of monolithic and bonded ultra‐high molecular weight polyethylene (UHMWPE) with high‐temperature resistant basalt/polyetherimide (B/PEI) composite is presented. Individual composite laminates were fabricated using vacuum‐assisted compression molding. Subsequently, cylindrical test coupons were cut using a high‐pressure waterjet. A suitable adhesive grade was used for the bonding of two different composite types. The dynamic compression studies were conducted on a split‐Hopkinson pressure bar (SHPB). For identical incident energies, the range of strain rates attained by monolithic UHMWPE, B/PEI and bonded composites differed significantly. Monolithic UHMWPE achieved the highest rates of loading, whereas higher stresses were recorded for the B/PEI composite. Yet, monolithic UHMWPE, owing to higher constant stress plastic flow, results in higher toughness. Bonded composites revealed hybrid properties with delamination of UHMWPE as the primary failure mode. High‐speed imaging exposed severe deformation of UHMWPE during dynamic compression. SEM micrographs revealed fiber pull‐out and deforming behavior of UHMWPE and brittle failure of B/PEI composite. B/PEI in a bonded composite system never failed under dynamic compression within the experimental range, thus providing a window of opportunity to tailor‐make better ballistic and blast protection materials. [ABSTRACT FROM AUTHOR]