Vol 5 Issue 4 October 2017-December 2017

Abstract: This paper represents the analysis and design of two-stage operational transconductance amplifier (OTA) used in switched-capacitor (SC) circuits. The existing design methods for two-stage OTAs often lead to sub optimal solutions because they decouple inter-related metrics like noise and settling performance. In this approach, the cadence tool is used to analysis the transient response, AC response and phase plot of the OTA and also the settling time has been observed on the simulation. For the optimization routine, there is no need to interface with a circuit simulator because all significant devices parasitic are included in the tool. The simulation results show that a 90-nm prototype amplifier achieves the settling time of 1.5 ns with reduced integrated noise while consuming 2.3 mW from a 1.1V power supply with phase plot for 174 degree.

Keywords: Two stage OTA, transient response, settling time, power, cadence tool.

Title: Analysis and Design of Operational Transconductance Amplifier (OTA) using Cadence tool

Author: S.Hari Krishnan, H.Hemavathi

International Journal of Engineering Research and Reviews    

ISSN 2348-697X (Online)

Research Publish Journals

Abstract: The comminution and leaching unit operations play a vital role in the extraction process of valuable minerals from ores. Historical research efforts have focused more on optimizing these two unit operations individually rather than as an entire integrated process. The approach employed in modern day research is now driven by the process intensification philosophy. Process intensification detects that developing an integrated approach to mineral processing systems and flow sheets leads to improved efficiency of the overall process and can help attain optimum recovery and a reduction in energy and material costs. In this article, we present laboratory scale batch grinding and leaching profiles of a mono-sized gold ore sample (-1700 + 850 μm). The sample was obtained from a run-of-mine (ROM) ore of one the leading gold processing plants in South Africa. Various combinations of grinding media fill level and ball size were investigated, showing that breakage is more pronounced for the larger ball sizes tested.  We also found that using a higher media filling (J = 30%) and a larger media size (30 mm) consumed more energy with less gold recovered during a 24 hour leaching period, compared to when a smaller J of 15% and 20 mm media was used. Our results show that efficient application of energy is vital and maximum profit is a complex function of energy usage and particle size.       

Keywords: gold, Historical research, mineral processing, energy, material costs.

Title: Determining Optimum Wet Milling and Leaching Parameters for Maximum Recovery of Gold

Author: Nkosikhona Hlabangana, Nonhlanhla G. Mguni, Siboniwe Bhebhe, Gwiranai Danha, Joel Tshuma

International Journal of Engineering Research and Reviews

ISSN 2348-697X (Online)

Research Publish Journals

Abstract: Research and development play a crucial role in innovation processes. R+D is an investment in the future, resulting in new products, processes and services through the transformation of newly developed technologies and thus far unexploited potential. This document provides an overview of the stages and outcomes of the research and development process in question. INFONIA Foundation was entrusted with complex research tasks in the project entitled Piac_13-1-2013-0242 automated cable standardization technology research. The main task of the research institute was to prepare and support the Client’s decisions, in the Piac_13-1-2013-0242 Automated cable customization technology research for VLG Ltd.

Keywords: smart cable, research report, R+D development, case study.

Title: Case Study: Researching a Smart Cable

Author: Árpád Rab

International Journal of Engineering Research and Reviews    

ISSN 2348-697X (Online)

Research Publish Journals

Abstract: Polyurethane (PU) is a dressing agent with high absorption and moisture permeability and has excellent wound healing effects. Silk fibroin (SF) is an attractive biomaterial as per clinical studies. In this study, a novel PU series was synthesized using bio-based isosorbide and SF at different ratios. The successful synthesis of the PU-SF series was confirmed by Fourier transform-infrared spectroscopy. The wettability of the polymer surface was evaluated based on the contact angle. The thermal properties were determined by thermogravimetric analysis to evaluate the thermal stability. The mechanical properties of the PU-SF series were evaluated using an Instron universal testing machine. The addition of SF significantly improved the tensile properties of the PU-based material. The mouse myoblast cell line C2C12 was used as a model for in vitro experiments with the PU-SF series to ensure biocompatibility and non-toxicity; the cell response improved with increasing SF content. The PU-SF series shows significant potential for specific regenerative medicine applications due to its biocompatibility and good physical properties, including in wound dressing.

Keywords: Polyurethane, silk fibroin, wound dressing, isosorbide, biocompatibility.

Title: Preparation and Properties of Biocompatible Polyurethane based on Isosorbide and Silk Fibroin

Author: Sarah Kim, Jong-Wan Kim, Jae-Ryung Cha

International Journal of Engineering Research and Reviews

ISSN 2348-697X (Online)

Research Publish Journals