Development of ZnTe:Cu Contacts for CdTe Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-08-320

The main focus of the work at NREL was on the development of Cu-doped ZnTe contacts to CdTe solar cells in the substrate configuration. The work performed under the CRADA utilized the substrate device structure used at NREL previously. All fabrication was performed at NREL. We worked on the development of Cu-doped ZnTe as well as variety of other contacts such as Sb-doped ZnTe, CuxTe, and MoSe2. We were able to optimize the contacts to improve device parameters. The improvement was obtained primarily through increasing the open-circuit voltage, to values as high as 760 mV, leading to device efficiencies of 7%

Development of UV Spectrophotometric Method for Estimation of Barberin in Bulk and Pharmaceutical Dosage Form

A simple, accurate, precise spectrophotometric method was developed for the estimation of barberin (BRN). The optimum condition for the analysis of the BRN was studied. BRN was subjected to stress degradation under different conditions like acidic, alkali, neutral, oxidation, photolytic, and thermal degradation as per recommended by the International Conference on Harmonization (ICH). The samples thus prepared were used for degradation studies by with the developed method. The lambda max i.e. absorption maxima found at 348 nm and calibration curve linear over the range of 0-40 µg /ml. The standard regression equation and correlation coefficient fond to be y = 0.02x - 0.0189 R² = 0.9982 respectively. % RSD found to be less than one. The accepted limits of accuracy (recovery) were found to be 97.75% and all observed data are within required range which indicates good recovery value. LOD and LOQ found to be 0.0529 µg /ml and 0.2167 µg /ml respectively by developed UV spectroscopic method

Fire hazard and other safety concerns of photovoltaic systems

Photovoltaic (PV) modules are usually considered safe and reliable. But in case of grid-connected PV systems that are becoming popular, the issue of fire safety of PV modules is becoming increasingly important due to the employed high voltages of 600 to 1000 V. The two main factors, i.e., open circuiting of the dc circuit and of the bypass diodes and ground faults that are responsible for the fire in the PV systems, have been discussed in detail along with numerous real life examples. Recommendations are provided for preventing the fire hazards such as designing the PV array mounting system to minimize the chimney effect, having proper bypass and blocking diodes, and interestingly, having an ungrounded PV system

An efficient CDMA system based on Reed Solomon Code (RS code)

Accurate Error control is a necessary constraint for the design of Celluar Code Division Multiple Access ( CDMA ) systems. The Block codes can correct twice as many erasures as errors , the coded performance can be improved . In this paper , We propose ‘ An efficient Error correcting coding in CDMA systems. The system performance is improved using FEC based on Walsh code and PN sequence. The power consumption of transrecevier is the requirement for low power communication systems such as wireless personal area networks , low data rate networks. The FEC schemes are selected based on its performance. To improve communication robustness , the correcting capabilities shall be seen to determine the transmit power. The probability of incorrect Decoding can be significantly improved using RS codes.

Computation of photovoltaic parameters under lunar temperature variation

Photovoltaic (PV) arrays with regenerative-fuel-cell energy storage is a prime, power-system candidate for lunar photo-power. The PV module performance decreases at higher temperatures. Surface temperature variations of the moon are extreme, the maximum (noon) temperature being 384 K. The present work utilizes detailed computations of photovoltaic parameters with computer program developed earlier for the computation of optimum bandgaps of single- and two-junction solar cells at different temperatures, and calculates the power output of single and two-junction solar modules under different configurations which constitutes an improvement over the assumption of a linear variation of efficiency with temperature. The program also calculates the necessary PV-array size to satisfy stipulated levels of day- and night-time power consumption

Device for detailed analysis of leakage current paths in photovoltaic modules under high voltage bias

High voltages used in photovoltaic (PV) systems are known to induce long-term power loss in PV modules due to leakage current flowing through the module packaging materials. It has been difficult to identify the specific materials and interfaces responsible for degradation based on an analysis of only the total leakage current. A detailed investigation of the leakage current paths within the PV modules, under high voltage bias, is carried out by utilizing a device that measures the independent contributions of various paths in real-time. Knowledge about dominant leakage current paths can be used to quantify the physical and chemical changes occurring within the module packaging materials

Influenza Vaccine Production Capacity Building in Developing Countries: Example of the Serum Institute of India

AbstractIt is predicted that in case of an influenza pandemic, there will be a significant gap between potentially available vaccine supply and international demand. This paved the way for a WHO Global Pandemic Influenza Action Plan (GAP) aiming at increasing the world's production capacity for pandemic vaccine. In November 2006, six developing country manufacturers were awarded grants either to develop processes for production of inactivated or live attenuated seasonal and/or H5N1 influenza vaccines or for establishing filling facilities using imported antigens. In April 2009, spread of a new H1N1 influenza virus was identified which took a pandemic form. This paper gives an overview of influenza vaccine capacity building of developing country's manufacturers identified in WHO's GAP. Further, an account of developments at Serum Institute of India Limited (SIIL), one of recipients of WHO grant to develop pandemic influenza vaccine, are presented as a case study. Such initiatives have strengthened developing country vaccine manufacturers ability to respond to a pandemic situation in the future

High Throughput, Low Toxic Processing of Very Thin, High Efficiency CIGSS Solar Cells: Final Report, December 2008

The work carried out during this project presents the use of diethylselenium or other organometallic precursors as low-toxicity alternative selenium sources for preparing a high-quality absorber