Enhancing the photovoltaic performance and stability of QDSSCs using surface reinforced Pt nanostructures with controllable morphology and superior electrocatalysis <i>via</i> cost-effective chemical bath deposition

Srinivasa Rao, S.,Durga, Ikkurthi Kanaka,Kang, Tae-Su,Kim, Soo-Kyoung,Punnoose, Dinah,Gopi, Chandu V. V. M.,Eswar Reddy, Araveeti,Krishna, T. N. V.,Kim, Hee-Je The Royal Society of Chemistry 2016 Dalton Transactions Vol.45 No.8

<P>To make quantum-dot sensitized solar cells (QDSSCs) competitive, photovoltaic parameters such as the power conversion efficiency (PCE) and fill factor (FF) must become comparable to those of other emerging solar cell technologies. In the present study, a novel strategy has been successfully developed for a highly efficient surface-modified platinum (Pt) counter electrode (CE) with high catalytic activity and long-term stability in a polysulfide redox electrolyte. The reinforcement of the Pt surface was performed using a thin passivating layer of CuS, NiS, or CoS by simple chemical bath deposition techniques. This method was a more efficient method for reducing the electron recombination in QDSSCs. The optimized Pt/CuS CE shows a very low charge transfer resistance of 37.01 Omega, which is an order of magnitude lower than those of bare Pt (86.32 Omega), Pt/NiS (53.83 Omega), and Pt/CoS (73.51 Omega) CEs. Therefore, the Pt/CuS CEs show much greater catalytic activity in the polysulfide redox electrolyte than Pt, Pt/NiS and Pt/CoS CEs. As a result, under one-sun illumination (AM 1.5G, 100 mW cm(-2)), the Pt/CuS CE exhibits a PCE of 4.32%, which is higher than the values of 1.77%, 2.95%, and 3.25% obtained with bare Pt, Pt/CoS, and Pt/NiS CEs, respectively. The performance of the Pt/CuS CE was enhanced by the improved current density, Cu vacancies with increased S composition, and surface morphology, which enable rapid electron transport and lower the electron recombination rate for the polysulfide electrolyte redox couple. Electrochemical impedance spectroscopy and Tafel polarization revealed that the hybrid CEs reduce interfacial recombination and exhibit better electrochemical and photovoltaic performance compared with a bare Pt CE. The Pt/CuS CE also shows superior stability in the polysulfide electrolyte in a working state for over 10 h, resulting in a long-term electrode stability than Pt CE.</P>

Processing Polymers from ASR/ESR: Separation of Poly Vinyl Chloride (PVC) by Froth Flotation after Microwave Assisted Surface Modification

( Srinivasa Reddy Mallampati ),( Chi-hyeon Lee ),( Nguyen Thi Thanh Truc ),( Byeong-kyu Lee ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 3RINCs초록집 Vol.2015 No.-

One of the major problems in incineration for thermal recycling or heat melting for material recycling is the polyvinyl chloride (PVC) contained in ASR/ESR plastics. This is due to the production of hydrogen chloride, chlorine gas, dioxins, and furans originated from PVC. Therefore, the separation of PVC from ASR/ESR waste plastics is necessary before recycling. The separation of heavy polymers (PVC 1.42, PMMA 1.12, PC 1.22 and PET 1.27 g/cm³) from light ones (PE and PP 0.99 g/cm³) can be achieved on the basis of their density in wet gravity separation. However it is difficult to separate PVC from other heavy polymers basis of density. There are no simple and inexpensive techniques to separate PVC from other plastics. If hydrophobic the PVC surface is selectively changed into hydrophilic, where other polymers still have hydrophobic surface, flotation process can separate PVC from others. In the present study, the selective surface hydrophilization of polyvinyl chloride (PVC) by microwave treatment after alkaline/acid washing and with activated carbon was studied as the pre-treatment of its separation by the following froth flotation. In presence of activated carbon as absorbent, the microwave treatment could selectively increase the hydrophilicity of the PVC surface (i.e. PVC contact angle decreased about 19°) among other plastics mixture. At this stage, 100% PVC separation from other plastics could be achieved by the combination of the pre- microwave treatment with activated carbon and the following froth floatation. The hydrophilization of PVC by surface analysis would be due to the hydrophilic groups produced by microwave treatment with activated carbon. The effect of optimum condition and detailed mechanism onto separation efficiency in the froth floatation was also investigated.

Prevalence of diffuse idiopathic skeletal hyperostosis among elderly subjects referred for radiological investigation in tertiary hospital at Oman

Srinivasa Rao Sirasanagandla,Humoud Al Dhuhli,Ahmed Al Abri,Ahmed Salmi,Sathish Kumar Jayapal,Crosetto Sara,Sanjay Jaju 대한해부학회 2018 Anatomy & Cell Biology Vol.51 No.3

Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by calcification of different entheseal sites including the anterior longitudinal ligament of the spine. There is no documented information about DISH in Oman. This study determined the prevalence of DISH and associated factors among elderly subjects in a national tertiary care referral hospital in Oman. This retrospective study reviewed chest X-rays of all patients aged more than 50 years, referred to the radiology department of Sultan Qaboos University Hospital in the year 2016, based on the Resnick s criteria. The prevalence was expressed as proportions across age groups and sex. Chi-square test and logistic regression analysis was done to determine the association of the age and sex with DISH. A total of 1305 chest X-rays of patients were reviewed. The overall prevalence of DISH was 10%, with male to female ratio of 1.56:1. The odds ratio for males and increasing age were 1.63 (95% confidence interval [CI], 1.12‒2.3; P<0.05) and 1.34 (95% CI, 1.14‒1.58; P<0.001) respectively. The prevalence increased with age to maximum of 13% in the age group of ≤80. The pre-stage DISH prevalence was 9.3% and more frequently observed among males. Prevalence of DISH in the national tertiary care referral center in Oman is lower than in Jewish population, almost similar to Japanese, but higher than in Koreans. DISH prevalence is positively associated with age and sex. It is necessary to take appropriate precautionary measures to target the ageing population in Oman, especially elderly males.

A Zero Sequence Voltage Injection Method for Cascaded H-bridge D-STATCOM

Srinivasa Rao Yarlagadda,Mukesh Kumar Pathak 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

Load variations on a distribution line result in voltage fluctuations at the point of common coupling (PCC). In order to keep the magnitude of the PCC voltage constant at its rated value and obtain zero voltage regulation (ZVR), a D-STATCOM is installed for voltage correction. Moreover, the ZVR mode of a D-STATCOM can also be used to balance the source current during unbalanced loading. For medium voltage and high power applications, a D-STATCOM is realized by the cascaded H-bridge topology. In the ZVR mode, the D-STATCOM may draw unbalanced current and in this process is required to handle different phase powers leading to deviations in the cluster voltages. Zero sequence voltage needs to be injected for ZVR mode, which creates circulating power among the phases of the D-STATCOM. The computed zero sequence voltage and the individual DC capacitor balancing controller help the DC cluster voltage follow the reference voltage. The effectiveness of the control scheme is verified by modeling the system in MATLAB/SIMULINK. The obtained simulations are further validated by the experimental results using a dSPACE DS1106 and five-level D-STATCOM experimental set up.

China-Japan-Korea FTA: A Dual Track Approach to a Trilateral Agreement

( Srinivasa Madhur ) 세종대학교 경제통합연구소 2013 Journal of Economic Integration Vol.28 No.3

This paper argues that a China-Japan-Korea Free Trade Agreement (CJK FTA) will have large benefits to the three Northeast Asian countries and significant implications for global multilateral trade. However, several hurdles seem to make an expeditious completion of a CJK FTA, or even bilateral FTAs between Japan and China or between Japan and Korea extremely difficult. Thus, a pragmatic approach would be to follow a dual-track approach in which China and Korea fast-track the completion of a bilateral FTA between them and the three countries continue their negotiations for a trilateral FTA on a steady track. Neither of these attempts should, however, deter these countries from joining the larger multilateral deals they are pursuing such as the Regional Comprehensive Economic Partnership (RCEP) or the Transpacific Partnership (TPP).

Poster Session : PS 0066 ; Cardiology : Short Term Follow-Up of Acute Myocardial Infarction in Rural South Indian Population: Incidence of Sudden Death and Predictors of Mortality

( Srinivasa Raghavan Madhavan ),( Harikrishna Tandri ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: The mortality due to Coronary Artery Disease (CAD) in India is estimated to more than double from 13 million in the year 2000 to 30 million in 2015. Sudden cardiac death (SCD), defi ned as sudden unexpected death occurring within 1 hour of onset of symptoms, is a common initial manifestation of CAD. The primary objective of this study was to elicit the factors predicting mortality following Myocardial Infarction (MI), the secondary objective was to look at the incidence and factors predicting SCD. Methods: Patients with newly diagnosed MI, admitted to a tertiary care hospital in southern India, with no previous MI or cancer were eligible to participate. A case worker was assigned to each patient who contacted the patient every 3 months. Multivariate COX proportional hazard regression model was used to predict survival. Results: A total of 1027 participants were enrolled and followed for a mean 10.7(±7.45) months. Mean Age was 56(±12) years. During this period of time, 62 participants died and among those 26 deaths were adjudicated as SCD. While adjusting for other risk factors, age greater than 50 years, medication noncompliance and left ventricular ejection fraction (LVEF) < 30%, were signifi cant predictors of mortality (HR 3.48 (p 0.004), 14.32 (p <0.0001) and 2.58 (p 0.05) respectively). Conclusions: The overall one year mortality post MI in this rural south Indian population was around 6%, SCD accounted for more than half of the deaths. Medication noncompliance, age greater than 50 years and LVEF<30% were found to be good predictors of overall mortality. Follow up strategies, aimed at increasing compliance of patients in using medications post MI, would improve the mortality post MI.

Economic Analysis of Power Transmission Lines using Interval Mathematics

Srinivasa Kishore Teegala,Sunil Kumar Singal 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.4

A major portion of the capital costs in the present day power transmission systems are due to the cost of equipment and construction process. Transmission utilities in the recent years are drawing greater attention towards performing life cycle costing studies for cost management and decision making. However, the data involved in these studies are highly uncertain and the effect of these uncertainties cannot be directly included in the study process, resulting in inaccurate solutions. Interval mathematics provides a method for including these uncertainties throughout the cost analysis and provides final solution range in the form of intervals. In this regard, it is essential and extremely important that significant research has to be carried out in understanding the principles of life cycle costing methodology and its applicability to cost analysis of transmission lines along with uncertainties involved in the cost assessment process. In this paper, economic analysis of power transmission lines using interval mathematics has been studied. Life cycle costing studies are performed using net present value analysis on a range transmission lines used in India and the results are analyzed. A cost break even analysis considering right of way costs was carried out to determine the point of economy indifference.

Anatomy teaching in Saudi medical colleges- is there necessity of the national core syllabus of anatomy

Srinivasa Rao Bolla,Radi Ali Al Saffar 대한해부학회 2022 Anatomy & Cell Biology Vol.55 No.3

Curricular updates in medicine resulted in changes in gross anatomy teaching. We aim to find the trends and methods of gross anatomy teaching in medicine programs in Saudi Arabia. Further, examine whether the data would help to discuss whether a core Anatomy syllabus is required. A survey questionnaire based on the earlier studies, was sent to the anatomy faculty of 25 medical colleges to collect the data on the pedagogic and dissection/laboratory approaches, inclusion of radiological, clinical, surface anatomy sessions, and the total number of hours allocated for anatomy education. A total of 15 responses were received from different medical colleges of which nine provided complete details. A wide variation in the component and mode of delivery of anatomy was observed. The number of hours for the anatomy course ranged from 89 to 388 hours. These data will provide an update on gross anatomy teaching approaches, which will help in making informed decisions in course revisions and adopting the best practices. The variations in anatomy course with short duration raises concern about whether the essential learning outcomes are achieved to prepare a skillful and safe clinician? do we require a core syllabus of Anatomy to be adopted at the national level to achieve the essential learning outcomes? The AnatomicalSociety, UK has developed core syllabi of Anatomy for undergraduate medical, dental, nursing, and pharmacy students, which can serve as a guide in developing the core syllabus of Anatomy for medicine in Saudi.

Hybrid selective surface wettability separation of chlorinated plastics from E-waste shredder residue

( Srinivasa Reddy Mallampati ),( Min Hee Park ),( Je Haeng Heo ) 한국폐기물자원순환학회(구 한국폐기물학회) 2016 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2016 No.-

The presence of chlorinated/brominated halogenated plastics in automobile and electronic waste shredder residue (ASR/ESR), can contribute to the formation of hazardous chlorinated/brominated dioxins when subjected to incineration or thermal recycling. Treatment by a nanometallic Ca/CaO composite has been found to selectively hydrophilize the surface of polyvinyl chloride (PVC), enhancing its wettability and thereby promoting its separation from E-waste plastics by means of froth flotation. The treatment considerably decreased the water contact angle of PVC, by about 18°. The SEM images of the PVC plastic after treatment displayed significant changes in their surface morphology compared to other plastics. The SEM-EDS results reveal that a markedly decrease of [Cl] concentration simultaneously with dramatic increase of [O] on the surface of the PCV samples. XPS results further confirmed an increase of hydrophilic functional groups on the PVC surface. Froth flotation at 100 rpm mixing speed was found to be optimal, separating 100% of the PVC into a settled fraction of 96.4% purity even when the plastics fed into the reactor were of nonuniform size and shape. The total recovery of PVC-free plastics in E-waste reached nearly 100% in the floated fraction, significantly improved from the 20.5 wt% of light plastics that can be recovered by means of conventional wet gravity separation. The reagent employed during treatment is very small, and further surface contaminant removal on recycled E-waste plastics surfaces makes the developed process simple, effective and green.

Unilateral duplication of vas deferens: a cadaveric case report

Srinivasa Rao Sirasanagandla,Satheesha B. Nayak,Raghu Jetti,Kumar M. R. Bhat 대한해부학회 2013 Anatomy & Cell Biology Vol.46 No.1

Duplication of vas deferens is a rare congenital anomaly. All previously reported cases of this rare anomaly were identified during procedures such as orchiepexy, inguinal hernia repair, vasectomy, varicocoelectomy, and radical prostatectomy. Here, we report a case of unilateral duplicated vas deferens noted in an adult cadaver during regular dissection for medical students. The right spermatic cord contained 2 separate and completely developed cord-like structures. Both cords communicated separately with the tail of the epididymis. When traced cranially, both traversed the inguinal canal as content of the spermatic cord and finally fused at the level of the deep inguinal ring. No other variations were found in the testis or epididymis, and no variations were seen in the left spermatic cord. In addition, no associated renal abnormalities were noted.