199 research outputs found

    Doctor of Philosophy

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    dissertationCu(In,Ga)Se2 (CIGSe), CuZnSn(S,Se)4 (CZTSSe), etc., are the potential chalcogenide semiconductors being investigated for next-generation thin film photovoltaics (TFPV). While the champion cell efficiency of CIGSe has exceeded 20%, CZTSSe has crossed the 10% mark. This work investigates the effect of laser annealing on CISe films, and compares the electrical characteristics of CIGSe (chalcopyrite) and CZTSe (kesterite) solar cells. Chapter 1 through 3 provide a background on semiconductors and TFPV, properties of chalcopyrite and kesterite materials, and their characterization using deep level transient spectroscopy (DLTS) and thermal admittance spectroscopy (TAS). Chapter 4 investigates electrochemical deposition (nonvacuum synthesis) of CISe followed by continuous wave laser annealing (CWLA) using a 1064 nm laser. It is found that CWLA at ~ 50 W/cm2 results in structural changes without melting and dewetting of the films. While Cu-poor samples show about 40% reduction in the full width at half maximum of the respective x-ray diffraction peaks, identically treated Cu-rich samples register more than 80% reduction. This study demonstrates that an entirely solid-phase laser annealing path exists for chalcopyrite phase formation and crystallization. Chapter 5 investigates the changes in defect populations after pulse laser annealing in submelting regime of electrochemically deposited and furnace annealed CISe films. DLTS on Schottky diodes reveal that the ionization energy of the dominant majority carrier defect state changes nonmonotonically from 215±10 meV for the reference sample, to 330±10 meV for samples irradiated at 20 and 30 mJ/cm2, and then back to 215±10 meV for samples irradiated at 40 mJ/cm2. A hypothesis involving competing processes of diffusion of Cu and laser-induced generation of In vacancies may explain this behavior. Chapter 6 compares the electrical characteristics of chalcopyrite and kesterite materials. Experiments reveal CZTSe cell has an order of magnitude higher net carrier concentration and saturation current density, whereas five times smaller shunt resistance and depletion width at equilibrium compared to CIGSe. The TAS measurements suggest that the dielectric freezeout occurs at relatively higher temperatures (~ 150 K) and lower frequencies (< 1 MHz) for CZTSe cell. Both sample types show a broad DLTS signal, possibly indicating a parallel recombination process with carrier emissions

    Pulsed and continuous wave solid phase laser annealing of electrodeposited CuInSe2 thin films

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    pre-printCu(In,Ga)Se2 (CIGS) thin film photovoltaic absorber layers are primarily synthesized by vacuum based techniques at industrial scale. In this work, we investigate non-vacuum film synthesis by electrochemical deposition coupled with pulsed laser annealing (PLA) and or continuous wave laser annealing (CWLA) using 1064 nm laser. PLA results indicate that at high fluence (≥100 mJ/cm2) CuInSe2 films melt and dewet on both Mo and Cu substrates. In the submelt PLA regime (≤70 mJ/cm2) no change in XRD results is recorded. However CWLA at 50 W/cm2 for up to 45 s does not result in melting or dewetting of the film. XRD and Raman data indicate more than 80% reduction in full width at half maximum (FWHM) in their respective main peaks for annealing time of 15 s or more. No other secondary phases are observed in XRD or Raman spectrum. These results might help us in setting up the foundation for processing CIGS through an entirely non-vacuum process

    A study of HPLC patterns in patients of sickle cell anemia with analysis of red cell parameters

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    Background: Sickle cell disease (SCD) and its variants are genetic disorders resulting from the presence of a mutated form of hemoglobin, hemoglobin S (HbS). In this study we want to profile various types of haemoglobins and their relative percentage in sickle cell cases. Also, we will analyse RBC indices such as Hb, HCT, MCV, MCH, MCHC and RDW-CV.Methods: We analysed blood from 200 patients suspected to have Sickle cell hemoglobinopathies and subjected it to Sickling screening test. All positive cases will be subjected to HPLC to separate constituent haemoglobins and CBC analysis was done to check RBC indices.Results: In sickle cell trait (SCT) patients, there is a significantly higher level of HbA2 and HbS and significantly lower level of HbA. In sickle cell disease patients, there were significantly higher levels of HbA2, HbF and HbS and significantly lower levels of HbA. Both sickle cell trait and sickle cell disease patients had significantly lower levels of haematocrit, MCH and higher RDW CV.Conclusions: While analysing HPLC patterns, appearance of HbS, low levels of HbA and high levels of HbF and HbA2 should raise a suspicion for presence of Sickle cell hemoglobinopathy. There was statistical difference in levels of Hb, HCT, MCH and RDW-CV between cases and controls. High index of suspicion should be maintained when these parameters are on lower side, especially in population who is prone to have sickle cell disorders

    Genetic Algorithm Based for Identification of Heart Disease Risk Factors

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    The purpose of this thesis was to examine heart disease Angina risk factors. In particular, this Thesis was organized around the central theme of adiposity, which is a prevalent Complication following SCI. Study focused on understanding the relationships between activities of daily living (ADL) and risk factors including central adiposity, lipoproteins, and triglycerides. Using genetic algorithm, while controlling for pertinent covariates such as sex, age, and leisure time physical activity (LTPA), it was found that Mobility ADL (wheeling and transferring) were negatively associated with total and LDL-cholesterol. Study also examined whether individuals who considered themselves to be overweight subsequently had less favorable subjective well-being, and were more likely to report specific secondary complications than individuals who did not consider themselves to be overweight. In summary, the findings suggest that a) participation in specific types of ADL (i.e. Mobility ADL) are associated with a lower risk and should be further explored) elevated perceived adiposity is associated with specific secondary complications and lower subjective well-being. Overall thesis findings support the overwhelming evidence of the benefits of daily physical activity and maintaining a healthy bodyweight in the SCI population DOI: 10.17762/ijritcc2321-8169.150512

    Implementation Of 5S Quality Tool In Manufacturing Company: A Case Study

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    Abstract: 5S system is a technique which maintains the quality of working conditions in the organization. Amongst various available Lean resources, 5S is a powerful technique that can bolster objectives of the organization to get continuous improvement in performance and productivity. This paper presents the implementation of 5S in a manufacturing company &amp; 5S rating system was used to audit all changes in the company which enhanced the efficiency of the workers &amp; ultimately the productivity of the company is enhanced to 91 %

    Evaluation of the impact of the voucher and accreditation approach on improving reproductive behaviors and status in Cambodia

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    Background: Cost of delivering reproductive health services to low-income populations will always require total or partial subsidization by government and/or development partners. Broadly termed “demand-side financing” or “output-based aid,” these strategies include a range of interventions that channel government or donor subsidies to the user rather than the service provider. Initial pilot assessments of reproductive health voucher programs suggest that they can increase access, reduce inequities, and enhance program efficiency and service quality. However, there is a paucity of evidence describing how these programs function in different settings for various reproductive health services. Methods/Design: Population Council, funded by the Bill and Melinda Gates Foundation, intends to generate evidence around the “voucher and accreditation” approaches to improving the reproductive health of low-income women in Cambodia. The study comprises four populations: facilities, providers, women of reproductive age using facilities, and women and men who have been pregnant and/or used family planning within the previous 12 months. The study will be carried out in a sample of 20 health facilities that are accredited to provide maternal and newborn health and family planning services to women holding vouchers from operational districts in three provinces: Kampong Thom, Kampot, and Prey Veng and a matched sample of non-accredited facilities in three other provinces. Health facility assessments will be conducted at baseline and endline to track temporal changes in quality of care, client out-of-pocket costs, and utilization. Facility inventories, structured observations, and client exit interviews will be used to collect comparable data across facilities. Health providers will also be interviewed and observed providing care. A population survey of about 3,000 respondents will also be conducted in areas where vouchers are distributed and similar non-voucher locations. Discussion: A quasi-experimental study will investigate the impact of the voucher approach on improving reproductive health behaviors, reproductive health status, and reducing inequities at the population level and assess effects on access, equity, and quality of care at the facility level. If the voucher scheme in Cambodia is found effective, it may help other countries adopt this approach for improving utilization and access to reproductive health and family planning services

    Fermentative production of 2,3-Butanediol using bread waste – A green approach for sustainable management of food waste

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    Bread is Europe’s most wasted food, and the second most wasted food after potatoes in UK. Bread waste (BW) is a clean source of high-quality fermentable sugars. In this study, the potential of Enterobacter ludwigii to accumulate 2,3-butanediol (BDO) from BW was evaluated. Initially, the optimal inoculum size and yeast extract concentration were determined, followed by extraction of sugars from BW using acid and enzymatic hydrolysis. A glucose yield of 330–530 g/kg BW was obtained, and the sugars released were utilised for BDO production by E. ludwigii. The fed-batch cultivation using pure glucose and glucose rich hydrolysates from acid and enzymatic hydrolysis resulted in BDO titres of 144.5, 135.4, and 138.8 g/L, after 96 h, with yield of 0.47, 0.42 and 0.48 g/g yield, respectively. The innovation of the work is valorisation of BW to BDO with a circular biorefining approach and thus, reducing BW disposal and associated environmental burden

    Surgical and Trauma Capacity Assessment in Rural Haryana, India

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    Background: Trauma is a major global health problem and majority of the deaths occur in low- and middle-income countries (LMICs), at even higher rates in the rural areas. The three-delay model assesses three different delays in accessing healthcare and can be applied to improve surgical and trauma healthcare delivery. Prior to implementing change, the capacities of the rural India healthcare system need to be identified. Objective: The object of this study was to estimate surgical and trauma care capacities of government health facilities in rural Nanakpur, Haryana, India using the Personnel, Infrastructure, Procedures, Equipment and Supplies (PIPES) and International Assessment of Capacity for Trauma (INTACT) tools. Methods: The PIPES and INTACT tools were administered at eight government health facilities serving the population of Nanakpur in June 2015. Data analysis was performed per tool subsection, and an overall score was calculated. Higher PIPES or INTACT indices correspond to greater surgical or trauma care capacity, respectively. Findings: Surgical and trauma care capacities increased with higher levels of care. The median PIPES score was significantly higher for tertiary facilities than primary and secondary facilities [13.8 (IQR 9.5, 18.2) vs. 4.7 (IQR 3.9, 6.2), p = 0.03]. The lower-level facilities were mainly lacking in personnel and procedures. Conclusions: Surgical and trauma care capacities at healthcare facilities in Haryana, India demonstrate a shortage of surgical resources at lower-level centers. Specifically, the Primary Health Centers were not operating at full capacity. These results can inform resource allocation, including increasing education, across different facility levels in rural India

    SOSAS Study in Rural India: Using Accredited Social Health Activists as Enumerators

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    Background: Global estimates show five billion people lack access to safe, quality, and timely surgical care. The wealthiest third of the world’s population receives approximately 73.6% of the world’s total surgical procedures while the poorest third receives only 3.5%. This pilot study aimed to assess the local burden of surgical disease in a rural region of India through the Surgeons OverSeas Assessment of Surgical Need (SOSAS) survey and the feasibility of using Accredited Social Health Activists (ASHAs) as enumerators. Material and Methods: Data were collected in June and July 2015 in Nanakpur, Haryana from 50 households with the support of Indian community health workers, known as ASHAs. The head of household provided demographic data; two household members provided personal surgical histories. Current surgical need was defined as a self-reported surgical problem present at the time of the interview, and unmet surgical need as a surgical problem in which the respondent did not access care. Results: One hundred percent of selected households participated, totaling 93 individuals. Twenty-eight people (30.1%; 95% CI 21.0–40.5) indicated they had a current surgical need in the following body regions: 2 face, 1 chest/breast, 1 back, 3 abdomen, 4 groin/genitalia, and 17 extremities. Six individuals had an unmet surgical need (6.5%; 95% CI 2.45%–13.5%). Conclusions: This pilot study in Nanakpur is the first implementation of the SOSAS survey in India and suggests a significant burden of surgical disease. The feasibility of employing ASHAs to administer the survey is demonstrated, providing a potential use of the ASHA program for a future countrywide survey. These data are useful preliminary evidence that emphasize the need to further evaluate interventions for strengthening surgical systems in rural India
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