Natural & Applied Sciences

Natural & Applied Sciences Research Papers/Topics

Emerging Business Models for Open Source Hardware

The rise of Free and Open Source models for software development has catalyzed the growth of Free and Open Source Hardware (also known as " Libre Hardware "). Libre hardware is gaining significant traction in the scientific hardware community, where there is evidence that open development creates both technically superior and far less expensive scientific equipment than proprietary models. In this article, the evidence is reviewed and a collection of examples of business models is developed t...

Power and Energy Potential of Mass-Scale Photovoltaic Noise Barrier Deployment: A Case Study for the U.S.

Solar photovoltaic (PV) systems have the greatest potential to meet the scale of sustainable energy demands, yet large surface areas beyond rooftop areas are required. One source of additional surface area that avoids conflict with food production while scaling with population density is noise barriers, which provide dual use of land area both as noise abatement and energy generation. This paper provides a method to quantify the potential of mass scale deployment of photovoltaic noise barrier...

Energy Payback Time of a Solar Photovoltaic Powered Waste Plastic Recyclebot System

The growth of both plastic consumption and prosumer 3-D printing are driving an interest in producing 3-D printer filaments from waste plastic. This study quantifies the embodied energy of a vertical DC solar photovoltaic (PV) powered recyclebot based on life cycle energy analysis and compares it to horizontal AC recyclebots, conventional recycling, and the production of a virgin 3-D printer filament. The energy payback time (EPBT) is calculated using the embodied energy of the materials maki...

Technical Solar Photovoltaic Potential of Scaled Parking Lot Canopies: A Case Study of Walmart U.S.A.

Solar photovoltaic (PV) technology can provide sustainable power for the growing global population in cities, but it demands considerable land area. This is a challenge for densely populated cities. However, the stranded assets of non-productive parking lots areas can be converted to solar farms with PV canopies, enabling sustainable electricity generation while preserving their function to park automobiles. This study provides a method for determining the technical and economic potential for...

Inhibition of growth of S. epidermidis by hydrothermally synthesized ZnO nanoplates

The antibacterial effect of zinc oxide (ZnO#1) as prepared and annealed (ZnO#2) at 400 o C, Cu doped ZnO (CuZnO), and Ag doped ZnO (AgZnO) nanoplates on Staphylococcus epidermidis was investigated for the inhibition and inactivation of cell growth. The results shows that pure ZnO and doped ZnO samples exhibited antibacterial activity against S. epidermidis as compared to tryptic soy broth (TSB). Also it is observed that S. epidermidis was extremely sensitive to treatment with ZnO nanoplates a...

Factors Effecting Real Time Optical Monitoring of Fused Filament 3-D Printing

This study analyzes a low-cost reliable real-time optimal monitoring platform for fused filament fabrication-based open source 3-D printing. An algorithm for reconstructing 3-D images from overlapping 2-D intensity measurements with relaxed camera positioning requirements is compared with a single camera solution for single side 3-D printing monitoring. The algorithms are tested for different 3-D object geometry and filament colors. The results showed that both of the algorithms with a single...

Fabricating ordered 2-D nano-structured arrays using nanosphere lithography

Recent advances in the use of plasmonic metamaterials to improve absorption of light in thin-film solar photovoltaic devices has created a demand for a scalable method of patterning large areas with metal nanostructures deposited in an ordered array. This article describes two methods of fabricating ordered 2D nanosphere colloidal films: spin coating and interface coating. The two methods are compared and parameter optimization discussed. The study reveals that: For smaller nanosphere sizes, ...

Micro­Raman Scattering of Nanoscale Silicon in Amorphous and Porous Silicon

Thesize effect of nanoscale silicon in both amorphous and porous silicon was investigated with micro­Raman spectroscopy. Silicon nanostructers in amorphous silicon were deposited on quartz substrates by plasma enhanced chemical vapor deposition (PECVD) with deposition powers of 15, 30 and 50W. Micro­Raman spectra of the nanostructured silicon show the T 2g Raman active mode shifting from the 521 cm ­1 crystalline Si Raman line to 494, 499 and 504 cm ­1 as deposition power increased. Large...

Ambient-dependent Agglomeration and Surface-Enhanced Raman Spectroscopy Response of Self-Assembled Silver Nano-particles for Plasmonic Photovoltaic Devices

The agglomeration/dewetting process of thin silver films provides a scalable method of obtaining self-assembled nanoparticles (SANPs) for plasmonics based thin-film solar photovoltaic (PV) devices. Here, we show the effect of annealing ambiance on silver SANP average size, particle/cluster finite shape, substrate area coverage/particle distribution and how these physical parameters influence optical properties and surface-enhanced Raman scattering (SERS) responses of SANPs. Statistical analys...

General Design Procedure for Free and Open-Source Hardware for Scientific Equipment

Distributed digital manufacturing of free and open-source scientific hardware (FOSH) used for scientific experiments has been shown to in general reduce the costs of scientific hardware by 90–99%. In part due to these cost savings, the manufacturing of scientific equipment is beginning to move away from a central paradigm of purchasing proprietary equipment to one in which scientists themselves download open-source designs, fabricate components with digital manufacturing technology, and the...

Open-source Parametric 3-D Printed Slot Die System for Thin Film Semiconductor Processing

Slot die coating is growing in popularity because it is a low operational cost and easily scaled processing technique for depositing thin and uniform films rapidly, while minimizing material waste. The complex inner geometry of conventional slot dies require expensive machining that limits accessibility and experimentation. In order to overcome these issues this study follows an open hardware approach, which uses an open source 3-D printer to both fabricate the slot die and then to functional...

Development of a Resilient 3-D Printer for Humanitarian Crisis Response

Rapid manufacturing using 3-D printing is a potential solution to some of the most pressing issues for humanitarian logistics. In this paper, findings are reported from a study that involved development of a new type of 3-D printer. In particular, a novel 3-D printer that is designed specifically for reliable rapid manufacturing at the sites of humanitarian crises. First, required capabilities are developed with design elements of a humanitarian 3-D printer, which include, (1) fused filament ...

Micromorphology analysis of sputtered indium tin oxide fabricated with variable ambient combinations

Micromorphology analysis of sputtered indium tin oxide fabricated with variable ambient combinations. Abstract This study experimentally investigates the fractal nature of the 3-D surface morphology of sputtered indium tin oxide (ITO) fabricated with five sets of ambient combinations. The samples were prepared on glass substrates by DC magnetron sputtering using argon, argon with oxygen, argon with oxygen and nitrogen, argon with oxygen and hydrogen and argon with oxygen, nitrogen and hydroge...

Effects of silver catalyst concentration in metal assisted chemical etching of silicon

A systematic investigation is performed to determine the effects of the concentration of silver on metal assisted chemical etching (MaCE) on nanostructure formation mechanisms on silicon as well as their resultant optical properties. Silver nitrate concentrations of 0.008M, 0.004M, 0.003M and 0.002M with hydrogen fluoride were used for the preparation of p-type silicon nanostructures. Experimentally it is observed that when the catalysis molarity concentration is decreased in the etching proc...

Properties of Al-Doped Zinc Oxide and In-Doped Zinc Oxide Bilayer Transparent Conducting Oxides towards Solar Cell Applications

Novel aluminum and indium doped zinc oxide bilayer transparent conducting oxide thin films have been developed by simple sol gel spin coating and annealed at 500 C for an hour under nitrogen ambient towards solar cell applications. The structural, electrical and optical properties of both the as deposited and annealed bilayer thin films are characterized. X-ray diffraction studies showed a hexagonal wurtzite-type structure of ZnO with (002) orientation, which was enhanced with annealing. In a...


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