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This research delves into the slurry erosion behavior of Ni-Al and Fe-Cr coatings, applied using arc wire spraying (AWS) on hydro machinery SS316 steel. The surface and cross-section microstructures were analyzed using backscattered-scanning electron microscopy, Vickers microhardness, porosity percentage, and surface roughness testing, and bonding strength. Furthermore, slurry erosion tests were also performed to evaluate the mass loss for the coated and uncoated samples. Subsequent slurry erosion testing, under diverse parameters, unveiled the exceptional erosion resistance of Ni-Al coatings across varying jet velocities, slurry concentrations, and impingement angles. Moreover, analysis of the eroded surface was done with the assistance of FESEM images to evaluate the type and severity of the erosion. The analysis of erosion mechanisms, such as ploughing, cratering, micro-cutting, ductile failure, delamination, and roughened surfaces, provides nuanced insights into coatings responses to abrasive slurry particles. [ABSTRACT FROM AUTHOR]

The study focuses on the characterization of Aluminum (Al-6061) coated with RF-sputtered Zinc Oxide (ZnO) thin film, aiming to understand the complex interactions between microstructure, wettability, cavitation resistance, and corrosion performance. The study involves the use of various analytical techniques such as Field Emission Scanning Electron Microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and water contact angle (WCA) measurements. The cavitation erosion testing has been conducted under various factors namely jet velocity (m/s), impingement angle (°), and stand-off distance (cm), respectively, and that too at various levels. Further, with the use of RSM, the study also contributes to the interplay in between factors and acquiring optimized results. Moreover, the findings of the study provide valuable insights into the effectiveness of the ZnO coating in enhancing corrosion resistance and reducing mass loss due to cavitation erosion. The study's results offer significant implications for the engineering and design of protective coatings for Aluminum surfaces, with the potential to enhance durability and performance in various industrial applications. [ABSTRACT FROM AUTHOR]

This work presents a novel insight into slurry erosion behavior of thin layer of carbon fiber–epoxy-based composite adhered on 16Cr5Ni steel (adhesive coating) to evaluate its viability as a feasible candidate for slurry erosion applications. Experiments were conducted on a laboratory-developed slurry erosion test rig under accelerated conditions to study the effect erosion parameters namely slurry concentration, impact angle, and impact velocity. Under all the experimental conditions, adhesive coating showed better slurry erosion resistance in comparison with bare 16Cr5Ni steel specimens. Scanning electron microscopy analysis revealed that in the case of bare 16Cr5Ni steel; ploughing, micro-cutting, crater, plastic deformation, and lip formation were identified as main mechanism responsible for slurry erosion, whereas in the case of adhesive coating; pitting, cracking, fracturing, and shearing-off were found to be mainly responsible for material loss. It implies that adhesive coating showed a brittle mode of failure under slurry erosion conditions, whereas 16Cr5Ni steel exhibited a ductile mode of erosion. [ABSTRACT FROM AUTHOR]

Cavitation erosion (CE) poses a significant challenge in the operation and maintenance of hydropower turbines, leading to substantial economic and operational losses. This study addresses this issue by investigating the effectiveness of plasma-sprayed coatings in mitigating CE on SS316 steel. Si3N4+TiC + VC and Cr-Ni based coatings were applied using a plasma spraying process. The research encompasses a comprehensive analysis of the coatings' characteristics, including microhardness, surface roughness, porosity percentage, and coating thickness. Furthermore, CE tests were conducted under various conditions, considering factors such as impingement angle, stand-off distance, and jet velocity. The eroded surfaces were analyzed using scanning electron microscopy (SEM) to gain insights into the failure modes. The findings demonstrate that the Si3N4+TiC + VC and Cr-Ni based coatings significantly enhance the resistance of SS316 steel to CE. [ABSTRACT FROM AUTHOR]

Parasite of genus Leishmania viz. L. donovani and L. infantum cause visceral leishmaniasis (VL) or Kala-azar, systemic disease with significant enlargement of the liver and spleen, weight loss, anemia, fever and immunosuppression. The silent expansion of vectors, reservoir hosts and resistant strains is also of great concern in VL control. Considering all these issues, the present study focused on in vitro and in vivo antileishmanial screening of ellagic acid (EA) against L. donovani. The in vitro study was performed against the protozoan parasite L. donovani and a 50% inhibitory concentration was calculated. The DNA arrest in the sub-G0/G1 phase of the cell cycle was studied. In vivo studies included the assessment of parasite burden and immunomodulation in response to treatment of ellagic acid in BALB/c mice. The levels of Th1 and Th2 cytokines and isotype antibodies were assessed in different groups of mice. EA showed in vitro parasiticidal activity with IC50 18.55 µg/mL and thwarted cell-cycle progression at the sub-G0/G1 phase. Administration of ellagic acid to the BALB/c mice reported diminution of splenic and hepatic parasite burden coupled with an expansion of CD4+ and CD8+ T lymphocytes. EA further potentiated a protective immune response with augmentation of Th1 type immune response evidenced by elevation of serum IgG2a levels and DTH response. EA was reported to be safe and non-toxic to the THP-1 cell line as well as to the liver and kidneys of mice. These findings endorse the therapeutic potential of EA with significant immunomodulation and can serve as a promising agent against this debilitating parasitic disease. [ABSTRACT FROM AUTHOR]

To solve various issues, encountered in single phase power system, In this paper, Impedance Matching Transformer as a Balance Traction transformer is proposed. The main components of the proposed scheme are Impedance Matching Transformer with a three phase full bridge converter (FBC) as controller. The balance transformer is used to supply to the two single phase electrical railway traction load with 27.5 kV and low level three voltages converter. Hence, there is no need of additional auxiliary transformer to match the voltage of the converter. The method has low cost and less area requirement. The paper elaborates the operating principles of Impedance matching transformer and shows the current transforming relationship, the compensating principle, mathematical model. Simulation results on MATLAB are presented to authenticate the performance of the traction transformer. [ABSTRACT FROM AUTHOR]

The traditional heating, ventilation, and air conditioning (HVAC) system depends on wired mechanical thermostats and regulators deployed at various points in the industrial environment for temperature monitoring. Due to ineffective dynamic changes according to the environment, the traditional HVAC system consumes more electrical energy. Next-generation wireless network (NGWN) systems play a vital role in improving the overall efficiency of the system by continuous monitoring and analysis. A small-scale industry using HVAC systems needs an active smart energy saver technique for maintaining an economical budget. This work uses MATLAB software to simulate and analyze the utilization of fuzzy-based NGWN to reduce the energy consumption requirements of small-scale manufacturing. In the model, a fuzzy rule is designed and applied to a small-scale enterprise divided into five sectors, one of which is temperature sensitive, with the goal of lowering the energy bill. The model employs fuzzy rules to enhance the NGWN, which minimizes the energy usage cost by 30% as compared with the traditional existing HVAC systems. [ABSTRACT FROM AUTHOR]

Looming drug resistance cases of leishmaniasis infection are an undeniably serious danger to worldwide public health, also jeopardize the efficacy of available drugs. Besides this, no successful vaccine is available till date. Since the ancient era, many plants and their parts have been used as medicines against various ailments. Hence, the importance of drug development for new molecules against Leishmania infection is significant that is a cost-effective and safer drug preferably from the natural herbal resources. We evaluated the GC–MS screening and efficacy of Putranjiva roxburghii (PR) against the sensitive and resistant promastigotes of L. donovani. GC–MS profiling revealed that the extract was rich in myo-inositol-4-C-methyl, azulene and desulphosinigrin. Quantitative investigation of phytoconstituents confirmed that PR was rich in phenols, flavonoids and terpenoids. We found an IC50 25.61 ± 0.57 µg/mL and 29.02 ± 1.21 µg/mL of PR against sodium stibogluconate sensitive and resistant strain respectively. It was found to be safer in cytotoxicity assay and generated ROS mediated oxidative stress in the parasitic cells which was evidenced by the increased and decreased levels of superoxide radicals, lipid peroxidation products, lipid bodies and levels of thiol, plasma membrane integrity respectively. Therefore, our results support the importance of P. roxburghii as a medicinal plant against L. donovani and showed potential for exploration as an antileishmanial agent. [ABSTRACT FROM AUTHOR]

Honey bee glue (HBG) or propolis is produced by honey bees and used as cementing material for sealing within the hive which is considered as a waste by the beekeepers. Due to its umpteen biological properties, it is having the potential for drug development against infectious diseases. The management of leishmaniasis relied wholly on injectable chemotherapeutic agents with a lengthy regimen and no vaccine is available. Moreover, the growing drug resistance alarming the entire community about the upcoming menace. Hence, it is of utmost importance to discover and explore new compounds against Leishmania infection, which are effective, safe, and cheaper. The present study was aimed to evaluate the efficacy of Indian honey bee glue (HBG), a natural, resinous by-product of the apiculture industry against the promastigote and amastigote forms of the sensitive and resistant strains of Leishmania donovani. HBG was characterized through GC-MS screening and phytochemical (qualitative and quantitative) analysis was done. In vitro (anti-promastigote) and ex vivo (anti-amastigote) activities against sensitive and resistant strains of L. donovani were assessed. Cytotoxicity, ROS (reactive oxygen species) generation, cell membrane integrity, and cell cycle analysis were evaluated. Chemical characterization by GC-MS revealed the presence of different biologically active components in honey bee glue (HBG). Our results showed the activity of HBG with an IC50 of 27.95 ± 1.53 μg/mL and 29.43 ± 1.54 μg/mL against the sensitive and resistant L. donovani promastigotes respectively. An IC50 of 20.93 ± 1.35 μg/mL and 20.22 ± 1.53 μg/mL was observed against the sensitive and resistant amastigotes of L. donovani. Moreover, the cytotoxicity test against the human cell line showed a CC50 value of 811.30 ± 73.44 μg/mL. In addition to this, it enhanced the ROS production and oxidative stress exhibited by the altered levels of lipid peroxidation, superoxide radicals, lipid bodies, and cell membrane integrity within the parasitic cells and mediated their killing by arresting the DNA in the sub-G0/G1 phase of the cell cycle. The antiparasitic action together with GC-MS data revealed the importance of this by-product from the apiary industry. Therefore, HBG can be a good option to develop a new drug molecule against the deadly infection of Leishmania eventually. [ABSTRACT FROM AUTHOR]

The menace of the enfeebling disease leishmaniasis prevails due to the inaccessibility of effective vaccine and chemotherapy. Hence in the pursuit of finding novel alternative options with reasonable efficacy, immunomodulation, leishmanicidal activity and fewer side effects, screening of compounds from natural sources is needed. This study was focused on in vitro and in vivo antileishmanial screening of gallic acid (GA) against Leishmania donovani infection in BALB/c mice. GA showed in vitro parasiticidal activity and IC50 value of 19.59 ± 0.74 µg/ml and is able to arrest cell cycle at the sub‐G0/G1 phase. The therapeutic potential of gallic acid was assessed in the L. donovani‐infected BALB/c mice. GA reported a reduction in parasite burden and augmentation of CD4+ and CD8+ T lymphocytes. Also, the polarization of mouse immune status to protective Th1 response was evidenced by increased delayed‐type hypersensitivity response and levels of IgG2a, reactive oxygen species and nitric oxide. GA was reported to be safe and non‐toxic to human cell line THP‐1 and also to the liver and kidney of mice. Hence, the findings of the present study indicate the possible role of GA in the strengthening of host immune system and thus facilitating the clearance of leishmanial infection and conferring protection. [ABSTRACT FROM AUTHOR]

Due to advantages such as being economical, environment friendly and taking less time to reach destination, electrified railway traction system is used widely around the world as a significant means of mass and public transportation. With the development of electrified railway system, the power quality of traction grid becomes more serious. The electric power to railway trains is supplied through the transformer. Traction transformer is one of best solution to improve power quality related to electrical railway traction Power system. For this purpose, different traction transformer like Scott transformer, V-V transformer, YN/VD transformer, YD and Impedance matching transformer are studied, modeled and analyzed using MATLAB Simulink/Software. In this paper, a number of traction transformers are considered in the electrified railway traction power system. Due to the single phase & non-linear load behavior of electrical railways traction system, it has many issues of power quality like reactive power, Grid unbalance currents, harmonics etc. This problem can be solved by implementation a two single phase electrified railway traction system with a suitable traction transformer YD along with full bridge Converter. The full bridge converter (FBC) is used to transfer active power and suppressing the harmonics. The simulation results verify the effectiveness of the traction transformer. [ABSTRACT FROM AUTHOR]

To foster sustainable, low-emission development, renewable energy is the best solution for electricity supply, however solar and wind energy are more variable and uncertain than conventional sources. The demand of electricity can be compensated by involving these into power system planning and operations. Grid integration is the efficient ways to deliver variable renewable energy to the grid. Renewable energy is increasing in popularity worldwide. Since renewable energy is intermittent, the integration of renewable energy resources into the power grid infrastructure is a challenging task because the requirements for a power-electronic interface are not just the renewable energy source itself but also its effect on the operation of the power structure, particularly if an intermittent power source is used. This paper discusses the definition, challenges and possible solutions of Renewable Energy Sources (RES) based network incorporation into the energy system. The history of RES with its environmental implications and implementation is also being addressed with a study for primary use of RES and of non-RES in India. [ABSTRACT FROM AUTHOR]

In this work, high velocity oxy fuel (HVOF) method based spray coatings namely Cr3C2-25NiCr and WC-10Co-4Cr have been deposited on AISI304 turbine steels. An attempt has been made to analyze the coatings under accelerated slurry erosion conditions by employing a laboratory-developed slurry erosion testing set-up. The testing has been performed under varied conditions of slurry concentration, impact velocity and impact angle using the Taguchi approach. The microstructure of coating powder, erodent particles and deposited coatings have been studied using a scanning electron microscope (SEM) analysis. Erosion tests indicated that HVOF-spray Cr3C2-25NiCr and WC-10Co-4Cr coatings have been deposited on AISI304 steel exhibited significant improvements in the erosion resistance of AISI304 steel. The possible reason for such behaviour could be higher microhardness of HVOF-spray coatings in comparison with AISI304 bare steel. From SEM images of the samples taken prior and post slurry erosion tests, it has been observed that Cr3C2-25NiCr coating exhibited mixed (ductile and brittle) behaviour, though the WC-10Co-4Cr coating mostly demonstrated ductile behavior under conditions for erosion from the slurry. Apart from that, an attempt has been made to develop a functional equation based on the regression approach which could be employed to assess the erosion wear rate under a set of conditions. The predicted erosion wear results under varied conditions are in close relationship to experimental values. [ABSTRACT FROM AUTHOR]

In the present study, in-depth characterization of the high-velocity oxy-fuel (HVOF)-spray WC-Co-Cr and CoNiCrAlY coatings deposited on CA6NM turbine steel was done using scanning electron microscope (SEM), x-ray diffraction (XRD), roughness tester, microhardness tester, and optical image analyzer. Further, these coatings were tested under accelerated slurry erosion conditions using a high-speed erosion test rig. The effects of three different parameters related to actual operating conditions, namely erodent velocity relative to target surface, average erodent particle size, and slurry concentration on erosion behavior of these coatings, were investigated. SEM images on the specimen surface taken before and after erosion tests were carefully examined to understand the possible erosion mechanism. The study revealed that HVOF-sprayed WC-Co-Cr coating was found to impart higher erosion resistance in comparison with CoNiCrAlY coating under all the slurry erosion conditions. The reason for this behavior may be attributed to the higher hardness of HVOF-sprayed WC-10Co-4Cr coating in comparison with CoNiCrAlY coating. [ABSTRACT FROM AUTHOR]