Enhancing YBCO performance through fundamental process evaluation and characterization

The main goal of the program is to develop a fundamental understanding of the mechanisms that result in defects when thick YBCO films are prepared on multi-layered buffered, metal substrates

Development of practical high temperature superconducting wire for electric power application

The technology of high temperature superconductivity has gone from beyond mere scientific curiousity into the manufacturing environment. Single lengths of multifilamentary wire are now produced that are over 200 meters long and that carry over 13 amperes at 77 K. Short-sample critical current densities approach 5 x 104 A/sq cm at 77 K. Conductor requirements such as high critical current density in a magnetic field, strain-tolerant sheathing materials, and other engineering properties are addressed. A new process for fabricating round BSCCO-2212 wire has produced wires with critical current densities as high as 165,000 A/sq cm at 4.2 K and 53,000 A/sq cm at 40 K. This process eliminates the costly, multiple pressing and rolling steps that are commonly used to develop texture in the wires. New multifilamentary wires with strengthened sheathing materials have shown improved yield strengths up to a factor of five better than those made with pure silver. Many electric power devices require the wire to be formed into coils for production of strong magnetic fields. Requirements for coils and magnets for electric power applications are described

Impact of Real-time Assessment on the Training of Trainers for the Introduction of Rotavirus Vaccine in India

Background and aim: The introduction of rotavirus vaccine (RVV) in the universal immunization program of India is a big feat as it became the first nation in the World Health Organization (WHO) Southeast Asia region to do so. The involvement of huge numbers of frontline workers in introducing new vaccines in India and the underlined deficits in skills and knowledge require efficient capacity building programs. In view of this, limited research is available on the effectiveness of capacitybuilding interventions for healthcare workers. There is a dearth of studies from India measuring the “on-spot” impact of immunization trainings on healthcare workers. This study aims to assess the effectiveness of training in RVV introduction in enhancing the knowledge of the participants. Methods: The study was conducted among the participants attending two training workshops for the introduction of RVV: a state workshop in Pune and a regional workshop in Guwahati. The participants who attended the workshops and participated in both the pre- and post-test were included in the study. Real-time data was collected via Google forms pre- and post-training sessions. Results: In both workshops, a comparison of pre- and post-test scores of all questions taken together showed a significant increase in the knowledge level of theparticipants (p < 0.05). In Guwahati, the knowledge of the participants regarding doses of RVV, inadequate dosing, vaccine vial monitor (VVM), open vial policy, operationalization of RVV and monetary incentive increased significantly. In Pune, the knowledge of the participants regarding doses of RVV, bundling approach, schedule and dose, storage temperature for RVV, VVM, open vial policy, vaccine delivery and operationalization of RVV increased significantly after the training. Conclusion: A pre-planned and well-designed knowledge assessment tool can be used to understand the impact of training workshops in enhancing the knowledge and practical skills of the participants prior to the introduction of a new vaccine.&nbsp

Impact of Real-time Assessment on the Training of Trainers for the Introduction of Rotavirus Vaccine in India

Background and aim: The introduction of rotavirus vaccine (RVV) in the universal immunization program of India is a big feat as it became the first nation in the World Health Organization (WHO) Southeast Asia region to do so. The involvement of huge numbers of frontline workers in introducing new vaccines in India and the underlined deficits in skills and knowledge require efficient capacity building programs. In view of this, limited research is available on the effectiveness of capacity-building interventions for healthcare workers. There is a dearth of studies from India measuring the “on-spot” impact of immunization trainings on healthcare workers. This study aims to assess the effectiveness of training in RVV introduction in enhancing the knowledge of the participants. Methods: The study was conducted among the participants attending two training workshops for the introduction of RVV: a state workshop in Pune and a regional workshop in Guwahati. The participants who attended the workshops and participated in both the pre- and post-test were included in the study. Real-time data was collected via Google forms pre- and post-training sessions. Results: In both workshops, a comparison of pre- and post-test scores of all questions taken together showed a significant increase in the knowledge level of the participants (p < 0.05). In Guwahati, the knowledge of the participants regarding doses of RVV, inadequate dosing, vaccine vial monitor (VVM), open vial policy, operationalization of RVV and monetary incentive increased significantly. In Pune, the knowledge of the participants regarding doses of RVV, bundling approach, schedule and dose, storage temperature for RVV, VVM, open vial policy, vaccine delivery and operationalization of RVV increased significantly after the training. Conclusion: A pre-planned and well-designed knowledge assessment tool can be used to understand the impact of training workshops in enhancing the knowledge and practical skills of the participants prior to the introduction of a new vaccine

Impact of Real-time Assessment on the Training of Trainers for the Introduction of Rotavirus Vaccine in India

Background and aim: The introduction of rotavirus vaccine (RVV) in the universal immunization program of India is a big feat as it became the first nation in the World Health Organization (WHO) Southeast Asia region to do so. The involvement of huge numbers of frontline workers in introducing new vaccines in India and the underlined deficits in skills and knowledge require efficient capacity building programs. In view of this, limited research is available on the effectiveness of capacitybuilding interventions for healthcare workers. There is a dearth of studies from India measuring the “on-spot” impact of immunization trainings on healthcare workers. This study aims to assess the effectiveness of training in RVV introduction in enhancing the knowledge of the participants. Methods: The study was conducted among the participants attending two training workshops for the introduction of RVV: a state workshop in Pune and a regional workshop in Guwahati. The participants who attended the workshops and participated in both the pre- and post-test were included in the study. Real-time data was collected via Google forms pre- and post-training sessions. Results: In both workshops, a comparison of pre- and post-test scores of all questions taken together showed a significant increase in the knowledge level of theparticipants (p < 0.05). In Guwahati, the knowledge of the participants regarding doses of RVV, inadequate dosing, vaccine vial monitor (VVM), open vial policy, operationalization of RVV and monetary incentive increased significantly. In Pune, the knowledge of the participants regarding doses of RVV, bundling approach, schedule and dose, storage temperature for RVV, VVM, open vial policy, vaccine delivery and operationalization of RVV increased significantly after the training. Conclusion: A pre-planned and well-designed knowledge assessment tool can be used to understand the impact of training workshops in enhancing the knowledge and practical skills of the participants prior to the introduction of a new vaccine.&nbsp

Carbon Nanotubes for Space Photovoltaic Applications

Carbon nanotubes (CNTs) can be envisioned as an individual graphene sheet rolled into a seamless cylinder (single-walled, SWNT), or concentric sheets as in the case of a multi-walled carbon nanotube (MWNT) (1). The role-up vector will determine the hexagonal arrangement and "chirality" of the graphene sheet, which will establish the nanotube to be metallic or semiconducting. The optoelectronic properties will depend directly on this chiral angle and the diameter of the SWNT, with semiconductor types exhibiting a band gap energy (2). Characteristic of MWNTs are the concentric graphene layers spaced 0.34 nm apart, with diameters from 10-200 nm and lengths up to hundreds of microns (2). In the case of SWNTs, the diameters range from 0.4 - 2 nm and lengths have been reported up to 1.5 cm (3). SWNTs have the distinguishable property of "bundling" together due to van der Waal's attractions to form "ropes." A comparison of these different structural types is shown in Figure 1. The use of SWNTS in space photovoltaic (PV) applications is attractive for a variety of reasons. Carbon nanotubes as a class of materials exhibit unprecedented optical, electrical, mechanical properties, with the added benefit of being nanoscale in size which fosters ideal interaction in nanomaterial-based devices like polymeric solar cells. The optical bandgap of semiconducting SWNTs can be varied from approx. 0.4 - 1.5 eV, with this property being inversely proportional to the nanotube diameter. Recent work at GE Global Research has shown where a single nanotube device can behave as an "ideal" pn diode (5). The SWNT was bridged over a SiO2 channel between Mo contacts and exhibited an ideality factor of 1, based on a fit of the current-voltage data using the diode equation. The measured PV efficiency under a 0.8 eV monochromatic illumination showed a power conversion efficiency of 0.2 %. However, the projected efficiency of these junctions is estimated to be > 5 %, especially when one considers the enhanced absorption (from nanotubes whose bandgap is tailored to illumination) and electromagnetic coupling in a network of nanotubes

Review of Graphene Technology and Its Applications for Electronic Devices

Graphene has amazing abilities due to its unique band structure characteristics defining its enhanced electrical capabilities for a material with the highest characteristic mobility known to exist at room temperature. The high mobility of graphene occurs due to electron delocalization and weak electron–phonon interaction, making graphene an ideal material for electrical applications requiring high mobility and fast response times. In this review, we cover graphene’s integration into infrared (IR) devices, electro-optic (EO) devices, and field effect transistors (FETs) for radio frequency (RF) applications. The benefits of utilizing graphene for each case are discussed, along with examples showing the current state-of-the-art solutions for these applications

Development and fabrication of a Bi-2223 racetrack coil for generator applications

The development and fabrication of a layer-wound, epoxy-impregnated Bi-2223 high-temperature superconducting (HTS) racetrack coil which generates 40,000 ampere-turns of magnetomotive force (MMF) at 25 K is described. The coil was wound using Ag-sheathed Bi-2223 tape conductor laminated with copper foils for strength enhancement and insulated using a paper-wrap method. After epoxy impregnation, the coil was tested over a range of 16--25 K in a vacuum dewar using a closed-cycle helium refrigeration system. Descriptions of the tape lamination and insulation processing, the coil winding and impregnation, and the experimental test setup are given