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In a bid to expand the amount of information available on glass systems and their potential applications for radiation shielding design, glass samples with the compositions (30-x)SrO-xAl2O3–68B2O3–2V2O5(x = 5, 7.5, 10, 12.5&15 mol %) coded as SABV0 - 4 were prepared by the melt-quenching technique and analyzed for their optical, structural, physical, and radiation shielding features. The glassy (amorphous) nature of the SABV glass samples was affirmed by broad peaks of X-ray diffraction spectra. Calculated values of density and molar volume shown opposite behavior and the variation of these values were discussed as structural modifications in the glass matrix. From recorded optical absorption spectra optical band gap energy (Eg)-indirect transition, Urbach energy and optical basicity were estimated. FTIR spectra were recorded for all the samples in the range 400 cm−1 to 4000 cm−1. The FTIR absorbance spectra unveiled the SABV network structure mainly incorporating of BO3 and BO4 units. Raman spectroscopy is achieved to detect the structural changes and at higher wavenumber, B–O stretching modes in [BO3] observed with one or two NBO's. The results of ESR spectra of glasses have indicated the highly covalent environment of vanadium ions. Analysis of the photon shielding parameters of the glasses which were obtained primarily from FLUKA Monte Carlo simulations and XCOM computations revealed photon energy and glass chemical composition dependence. The mass attenuation coefficient and effective atomic number ranged from 0.2668 to 0.3385 cm2g-1 and 12.98–15.93 accordingly as the weight fraction of Sr increased from 16.06 to 26.72% in the glasses. Generally, photon shielding ability of the SABV glasses follows the trend: SABV0 > SABV1 > SABV2 > SABV3 > SABV4. The thermal neutron total cross section follows the same trend with values fluctuating between 71.9553 and 80.6268 cm−1. However, SABV1 showed superior fast neutron moderating capacity among the glasses. The present SABV glasses showed outstanding photon shielding ability compared to common shields. The prepared glasses are thus suitable candidates for radiation protection applications.

The Transmission part of the power sector is very much important as it deals with the huge losses of the complete power sector. Transmission substations play a key role in the power transmission process since the power generation at the power plants to the final stage at the consumer end utilization. The utmost care should be taken to protect these transmission substations as same as the care is taken to reduce the losses. The substation needs to be protected from blackouts which is the big problem of substations. For this, the substation high voltage equipment’s like GIS & Power Transformers are to be properly installed & energized according to the standards & care is taken for its maintenance. So, during the commissioning process which is after installation & before energization, there are different tests which are performed on high voltage equipment’s, especially the Gas Insulated Switchgear, in which the High Voltage & Partial discharge has huge impact as the ageing and the life time of GIS can be easily assessed & the GIS can be saved from the damage, tripping and the blackout of a substation. The procedure of the high voltage test and the partial discharge tests are clearly explained in this paper.

The PFBBF-x glasses with the chemical structure xPbF2 − (99.5 − x)(Bi2O3 + B2O3) − 0.5Fe2O3 (where x changes from 0 to 50 in the steps of 10) were prepared using melt quenching method. The concentration of PbF2 is increased gradually in the steps of 10 mol% at the cost of Bi2O3–B2O3, where the Bi2O3 and B2O3concentrations are reduced in 20:80 ratios. The prepared PFBBF glasses were investigated using XRD, UV–Visible, FTIR, Raman and Radiation shielding feature for their potential use in the optical applications and as shielding materials. With the excess of PBF2,we found an increase in percentage of the density to be 38.Moreover,the optical bandgap Eopt values for the PFBBF glasses rose from 2.826 eV (PFBBF-0) to 3.090 eV (PFBBF-50) while their Urbach energy (∆E) were less than 0.179 eV. Furthermore, refractive index (n) values for the glasses reduced from 2.4456 for PFBBF-0 glass to 2.3733 for PFBBF-50 glass. On the other hand, the Monte Carlo method was utilized to estimate the radiation shielding performance of our prepared PFBBF glasses. Analysis of linear ( $$\mu )$$ and mass attenuation ( $$\frac{\mu }{\rho })$$ coefficient showed that $$\mu {\text{and}} (\frac{\mu }{\rho })$$ decay from their maximum values 25.758 cm−1(4.146 cm2/g) at 0.1 MeV to 0.160 cm−1(0.036 cm2/g) at 6 MeV while values of effective atomic number varies from 14.44 to 75.16 for PFBBF-0–PFBBF-50, respectively. Generally, total mass stopping power and projected range of electron, proton, α-particle, and carbon ion varied according to the trend: PFBBF-0 > PFBBF-10 > PFBBF-20 > PFBBF-30 > PFBBF-40 > PFBBF-50. The increase in the concentration of PbF2was found to have a strong influence on the slow/thermal, and fast neutron transmission and cross sections in the glasses. A breakdown of obtained shielding parameters highlighted the superior shielding ability of the PFBBF glasses as against some previously investigated glasses and conventional radiation shields.

Decentralized distributed generation technologies based on renewable energy resources like Photo Voltaic (PV) or/and Wind Turbine Generators (WTG) address the above barriers to large extent and are...

Glasses of composition Al2O3–NaBr–B2O3 doped with copper ions prepared using melt quenching method. The effect of sodium bromide on alumino-borate glasses is investigated using various physical and spectroscopic methods. The increase in NaBr content decreased the density values of the samples nonlinearly which is attributed to replacement of relatively higher ionic radii of bromide ions (1.96 A) in the place of lower ionic radii of oxygen ions (1.4 A). At optical wavelengths, optical properties of the samples like band gap, Urbach energy, refractive index, etc., were evaluated and explained. Spin-Hamiltonian parameters (SHP) (gII, g⊥, AII and A⊥) were calculated from EPR spectra. The SHP values suggested the Cu2+ ion is in the ligand field surrounded by tetragonally contorted in octahedral locations with $${d}_{{x}^{2}-{y}^{2}}$$ as lowest energy state. The bonding coefficient ( $$\alpha^{2} ,\beta^{{2}} \,{\text{and}}\,\beta_{1}^{2}$$ ) values were also determined using broad absorption band in UV–visible spectra and EPR. A deconvoluted spectrum is used to get exact band positions in the FTIR spectra. Residual graph is drawn to know the percentage difference in experimental and simulated curves. FTIR spectra confirmed that the structure of the glass is build up of AlO3, AlO4, BO3 and BO4 units.

The current manuscript explains the significance of cadmium oxide (CdO) in the field of radiation shielding materials (RSM). The effect of CdO in lead boro-tellurite glasses studied using the essential properties (density, thickness, structural studies, etc.) for RSM. The glasses with the combination of CdO–PbO–TeO2–B2O3–CuO glasses with various concentrations of CdO were prepared using melt quenching method. The incorporation of PbO and CdO enhances the density of boro-tellurite glasses, which is the most important property of RSM. The increase in density is assigned to the creation of BO4 units in the glass matrix. Absorption spectra have shown a broad absorption band in near IR region, which is the characteristic of copper-doped glasses. Optical bandgap and Urbach energy evaluated from the spectra and refractive index, molar refraction, and electronic polarizability also calculated using the spectra and the density values. Smaller values in Urbach energy values suggested the less disorder in the glasses. Spin-Hamiltonian and bonding parameter values were calculated from EPR spectra. These parameters suggested that Cu2+-surrounded ligand environment is distorted tetragonally with octahedral sites and found that all the bondings are moderately ionic in nature. A deconvoluted spectrum is used to get exact band positions in the FTIR spectra. Residual graph is drawn to know the percentage difference in experimental and simulated curves. FTIR spectra confirmed the creation of BO4 units and the presence of BO3, BO4, TeO3, and TeO4 structural units.

Background: Hypertension is a chronic condition and has got significant role in the development of coronary heart disease, stroke and other vascular complications. To prevent some of the complications of hypertension regular intake of the prescribed treatment in the form of medicines (pills) is essential. Objectives: 1.To knows about the compliance of medication among hypertensive individuals of urban area of Eluru. 2. To find the demographic variables and other factors association with compliance in the study population. Materials and Methods: The present community based cross sectional study was conducted at Ashoknagar area of Eluru during the period from June 2013 to August 2013. Medication compliance (adherence) was calculated as the proportion of days covered for filled prescriptions of antihypertensive drugs. A total of 132 individuals were selected from Ashoknagar area of Eluru using simple random method. Importance of the study was explained to the participants and informed consent was taken. Results were analyzed and necessary statistical tests like proportions and chi square tests were applied. Results: Out of 132 individuals, no one of already diagnosed individuals in the age group of 20-30 years in our study. Compliance among hypertensive individuals was 74%. Compliance criteria in our study was those who taken medicines regularly 6 days out of 7 days in a week. Compliance was good among female sex and house wives and this association was statistically significant (P

Background: With respect to a multimedia presentation, style refers both to the style of the writing and to the appearance of the slides. Nowadays many faculty members are using different varieties of presentations through power point to many students. Really what extent it is useful for improving their knowledge level, effectiveness of the method and suggestions for improvement. Hence, this study was designed to conduct among medical students. Objectives: 1. To find the opinions of medical students about faculty presentations during lecture. Materials and Methods: The present institutional based cross sectional study was conducted at Alluri Sita Ramaraju Academy of Medical Sciences, Eluru, Andhra Pradesh, during the period from April 2016 to June 2016. A total of 125 individuals were selected from the one of the batch of Final MBBS, part-1 and randomly picked up this batch. Results were analysed and necessary statistical tests were applied. Results: Out of 125 study population, 58.4% were females and 41.6% were males. In the study population Only 46/125 (36.8%) students were opined faculty created interest during listening the class. Out of 125 students, 78 students opined that faculty members presented > 25 slides in their class. But there was no statistical difference was observed between number of slides and eye contact (P-0.32). About 90.4% students given opinion faculty taught relevant subject in their class. Very less proportion of faculty (25.6%) given mental breaks in the class during lecture. Conclusions: Based on the above study results, time taken by faculty is adequate, content delivered in the lecture is also good. But, only number of slides per class is more and mental breaks in the class is also less. In addition to regular practice, these changes also to be incorporated in their classes will give better output of the students in the areas of learning.

We report the method of tuning the thermal conductivity through the composition of multiwall carbon nanotube (MWCNT) dispersed ethylene glycol based nanofluids. The structure and properties of the MWCNTs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy and thermogravimetric analysis. A parallel plate thermal conductivity (PPTC) set up was fabricated and used for measurement of thermal conductivity of the nanofluids. We have prepared ethylene glycol based nanofluids containing 0.05, 0.1, 0.15, 0.20, 0.25 and 0.35 wt% of MWCNTs. The thermal conductivities of these fluids were measured by keeping them between the two (parallel) plates, referred as the hot and the cold plates, of the sample holder in the PPTC apparatus. The lower plate was water-cooled and the upper plate was heated. The temperature of the hot plate was varied between 35 and 80 °C. The thermal conductivity of the fluids was calculated using the one-dimensional heat conduction equation. According to our observation, an efficient heat transfer occurs through the nanofluids with an optimum concentration of 0.20 wt% of CNTs. Our work demonstrates the importance of the composition of the nanofluids and their structural defects in heat transfer.

High-strength bainitic wheel steels based on a new steel composition, namely MS2 [0.47% C, 0.87% Mn, 0.51% Si, 0.02% Mo, 0.03%Cu, 0.031% S, 0.033% P and rest Fe (weight percent)], were prepared by austempering treatment at 400 °C for 10, 30, 60 and 120 min. Corrosion behavior of the bainitic MS2 steels and normalized ferritic–pearlitic MS2 steel was studied and compared with that of the conventional ferritic–pearlitic wheel steel. Immersion test, electrochemical polarization and salt fog tests were carried out in 3.5% NaCl. Bainitic steels prepared with higher holding duration during austempering exhibited improved corrosion resistance on salt fog exposure. In contrast, bainitic steels prepared with lower holding duration during austempering resulted in better corrosion resistance on electrochemical polarization test. Salt fog test revealed gradual improvement in corrosion resistance for the bainitic steels with the successive holding. Improved corrosion behavior for the bainitic steel was related to the tiny and uniform spreading of iron carbide in the ferritic matrix resulting in the uniform coverage of the protective oxide layer on the steel surface. The enrichment of Si on the corroded surface of bainitic steel favored the formation of supermagnetic α-FeOOH of smaller particle size, improving the protective character of the rust against corrosion. Corrosion mechanisms for the ferritic–pearlitic and bainitic wheel steels were put forward.

A field experiment was conducted at the Agricultural College farm, Bapatla, during kharif and rabi 2017-18 and 2018-19. The experiment was conducted with variety BPT-5204 in a Randomized Block Design with ten treatments and three replications. The maximum plant height and drymatter production and seed yield were recorded with soil test based fertilizer recommendation with 10 t ha-1 FYM application which was at par with soil test based fertilizer recommendation alone and 7.5tha-1 targeted yield recommendation along with FYM (T5 and T10) and RDF with FYM (T6). seed yield of blackgram was significantly higher with soil test based fertilizer recommendation with 10 t ha-1 FYM application which was statistically at par with soil test based fertilizer recommendation alone (T2) and 7.5 t ha-1 targeted yield fertilizer recommendation with FYM (T10) compared to the rest of the treatments.

The increasing evidences of chronic surgical wounds and its associated complications in association with bacterial resistance to conventional antibiotics. Therefore, current antibiotic resistance crisis ultimately calls for the need of alternative antibacterial options and nanotechnology could be a solution. Furthermore, nano-antibiotics combinations will provide synergy with reducing the dosage of both agents, which can enhance biocompatibility and may aid in limiting the global crisis of emerging multidrug resistance. Specifically, in the context of cytotoxicity of nanoparticles, in the present study, green synthesized nanoparticles (Ag NPs, ZnO NPs) are used for the combination with antibiotic neomycin to investigate in-vivo wound healing activity to facilitate the tissue repair with minimized toxicity. Our results showed that, in-vivo potent synergetic wound healing effectiveness and faster wound contraction of prepared gel formulations from the green synthesized nanoparticles combinations with neomycin compared with neomycin or nanoparticles alone. These results point to the opportunity provided by this approach to realize the unmet needs and future directions with lustrous prospects in combinational herbal nanomedicine to combat the multi drug resistant bacteria.

We fabricated a new series of sodium tetraborate (Na2B4O7) containing TeO2, CaF2, and CuO for advanced performance in optical and radiation applications. PHILIPS (Xpert PRO) X-ray diffractometer was employed at room temperature (RT) to investigate the fabricated specimens' amorphous nature. Furthermore, UV–visible spectra and EPR spectra (~9.7 GHz and field modulation 100 kHz) were also achieved for the involved glass system. Moreover, FLUKA Monte Carlo simulations were successfully designed to describe the gamma transmission properties through the fabricated glass specimens. The results reveal that the optical band gap (Eg) decreased from 3.079 to 2.605 eV as the CaF2 content increased from 0 to 50 mol %. In the EPR spectra, fourth parallel hyperfine splittings in the high field are merged with the perpendicular hyperfine splitting's resulting in a single intense line. The gamma transmission studies show that the gamma absorption in the present glasses were highest at the least energy with the value of within the range: 0.0789–0.0229, 0.0789–0.0232, 0.0790–0.0236, 0.0790–0.0241, 0.0791–0.0246, and 0.0792–0.0253 cm2g−1 for CaF2 content of 0, 10, 20, 30, 40, and 50 mol %, respectively. It can be concluded that the present fabricated glass system has excellent and promising properties to use for optical and radiation applications.

A field experiment was conducted at the Agricultural College farm, Bapatla, during kharif and rabi seasons of 2017-18 and 2018-19. The experiment was conducted with blackgram variety BPT-5204 in a Randomized Block Design with ten treatments and three replications. The maximum grain yield, soil NPK status at post-harvest of rice and gross returns net returns, returns per rupee investment were recorded with soil test based fertilizer recommendation with 10 t ha-1 farm yard manure (FYM) application which was at par with soil test based fertilizer recommendation alone and 7.5 tha-1 targeted yield recommendation along with FYM and recommended dose of fertilizers (RDF) with FYM. Grain yield of rice was significantly higher with soil test based fertilizer recommendation with 10 t ha-1 FYM application which was statistically at par with soil test based fertilizer recommendation alone and 7.5 t ha-1 targeted yield fertilizer recommendation with FYM compared to the rest of the treatments.

The customer relationship management is playing vital role in engaging the customer in a competitive world especially in service sector. The present study has made an attempt to examine the CRM practices impact on the customer loyalty. The study has considered the BSNL as the sampling telecom company. The study adopted the convenient sampling method to collect the primary data. The study framed the two objectives and applied the various statistical tools. The study has considered the bivariate correlation to know the CRM practices relationship with the customer loyalty and the result indicated significant relation exists. The structure equation model has been applied and the result reveals that the impact of CRM practices on the customer loyalty has been observed. The study indicated that the service quality and brand image are having the significant effect on the loyalty of the customer in telecom sector (BSNL). This paper is useful to the telecom companies, TRAI and academic researchers.

A unique in-situ synthesis approach of formation-deformation-reformation routes lead to high crystalline core-shell Calcium Fluoride (CaF2) nanoparticles. They were tuned by the solvothermal process to achieve superior antireflection property (>95%) in the broadband region (400–1500 nm) after fabricating films by a dip coating method. These nanoparticles capped by cetyltrimethylammonium bromide (CTAB), to increase the porosity in single layer antireflective (AR) film to reduce the refractive index. This efficient antireflection layer with glass implemented on the c-Si solar cell to measure the efficiency and found out to be an improved performance (>5.7% net enhancement) compared to uncoated glass. In addition, the AR coatings exhibited a good mechanical strength which gives us the direction of future development for practical applications like highly transparent window coatings, optical and solar energy conversion applications.

An attempt was made to synthesis Al-5083alloy through high energy ball milling and densification through ECAP. The elemental powders consisting of Al5083 was milled for 5, 10 and 15 hrs using Retsch high energy ball mill (PM400). The physical and structural properties of mechanically alloyed particulates were characterised by diffraction methods and electron microscopy. The 15hrs nanocrystalline structured particulates of Al5083 alloy shows crystallite size of 15nm. Scanning Electron Microscope (SEM) reveals the morphology of alloy which is irregular shaped. The size of alloyed particulates also measured using SEM and found to be 7μm for 15hrs of milling. The 15hr milled alloy particulates were densified by ECAP through 90o die channel angle. Maximum densification of 92% and highest hardness of 63HRB was achieved for sample consolidated with route-A for two passes along with sintering.

The effect of milling time on consolidation of Al5083-5wt. % nanoyttrium oxide powders which are milled from 0-35 hours using planetary ball mill. nanocrystalline structure was observed after 10hours of milling. X-ray diffraction results reveals the formation of 57nm and 31nm for 20hr and 35hr of milling with increase in lattice strain. Circular and Elliptical morphology of milled powders were confirmed through SEM with decrease in particle size. The 90o die channel angle ECAP die was used to consolidate 20hr and 35hr milled powder aided with and without back pressure. The optical micrographs reveal the formation of fine grains. The35hr milled powder shows the maximum densification of 96% and 20hr milled powder shows maximum hardness of 82HRB was observed in 20hr milled powder. Both are consolidated for two passes in route-A and sintered at 430°C for one hour.