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Articles 60631 - 60660 of 197988

Full-Text Articles in Engineering

Nothing But A Number: A Closer Look At Stall Speed, Nihad E. Daidzic Mar 2020

Nothing But A Number: A Closer Look At Stall Speed, Nihad E. Daidzic

Aviation Department Publications

CFIS REPEAT IT LIKE A MANTRA: An airplane can stall at any airspeed, in any pitch attitude. Your trainer’s wing always stalls when it exceeds its critical angle of attack—and that can happen even if the airplane is pointed straight down and approaching VNE. So what do the stall speeds published in the pilot’s operating handbook mean? These only apply for the stated conditions: often level flight, maximum gross weight, and most forward center of gravity, with flaps retracted (VS1) or in the landing configuration (VS0). Factors such as total weight, load factor, power, and center of gravity location affect …

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New Constraint-Driven Mission Construct For Small Satellites And Constrained Missions, Lee Jasper, Barbara Braun, Lauren Hunt Mar 2020

New Constraint-Driven Mission Construct For Small Satellites And Constrained Missions, Lee Jasper, Barbara Braun, Lauren Hunt

Space Dynamics Laboratory Publications

Small satellites, though increasingly prevalent in the industry today, tend to not follow traditional development paths, technically or programmatically. In contrast to traditional requirements-driven missions, where meeting requirements is the primary metric of success, small satellite missions tend to be constraints-driven, where mission scope is tradable to maintain cost and schedule constraints.

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Clean, Robust Alkali Sources By Intercalation Within Highly Oriented Pyrolytic Graphite, Rudolph N. Kohn Jr., Matthew S. Bigelow, Mary Spanjers, Benjamin K. Stuhl, Brian L. Kasch, Spencer E. Olson, Eric A. Imhof, David A. Hostutler, Matthew B. Squires Mar 2020

Clean, Robust Alkali Sources By Intercalation Within Highly Oriented Pyrolytic Graphite, Rudolph N. Kohn Jr., Matthew S. Bigelow, Mary Spanjers, Benjamin K. Stuhl, Brian L. Kasch, Spencer E. Olson, Eric A. Imhof, David A. Hostutler, Matthew B. Squires

Space Dynamics Laboratory Publications

We report the fabrication, characterization, and use of rubidium vapor dispensers based on highly oriented pyrolytic graphite (HOPG) intercalated with metallic rubidium. Compared to commercial chromate salt dispensers, these intercalated HOPG (IHOPG) dispensers hold an order of magnitude more rubidium in a similar volume, require less than one-fourth the heating power, and emit less than one-half as many impurities. Appropriate processing permits exposure of the IHOPG to atmosphere for over ninety minutes without any adverse effects. Intercalation of cesium, potassium, and lithium into HOPG has also been demonstrated in the literature, which suggests that IHOPG dispensers may also be made …

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Banning Carbon Nanotubes Would Be Scientifically Unjustified And Damaging To Innovation, Daniel A. Heller, Prakrit V. Jena, Matteo Pasquali, Kostas Kostarelos, Lucia G. Delogu, Rachel E. Meidl, Slava V. Rotkin, David A. Scheinberg, Robert E. Schwartz, Mauricio Terrones, Yu Huang Wang, Alberto Bianco, Ardemis A. Boghossian, Sofie Cambré, Laurent Cognet, Simon R. Corrie, Philip Demokritou, Silvia Giordani, Tobias Hertel, Tetyana Ignatova, Mohammad F. Islam, Nicole M. Iverson, Anand Jagota, Dawid Janas, Junichiro Kono, Sebastian Kruss, Markita P. Landry, Yan Li, Richard Martel, Shigeo Maruyama, Anton V. Naumov, Maurizio Prato, Susan J. Quinn, Daniel Roxbury, Michael S. Strano, James M. Tour, R. Bruce Weisman, Wim Wenseleers, Masako Yudasaka Mar 2020

Banning Carbon Nanotubes Would Be Scientifically Unjustified And Damaging To Innovation, Daniel A. Heller, Prakrit V. Jena, Matteo Pasquali, Kostas Kostarelos, Lucia G. Delogu, Rachel E. Meidl, Slava V. Rotkin, David A. Scheinberg, Robert E. Schwartz, Mauricio Terrones, Yu Huang Wang, Alberto Bianco, Ardemis A. Boghossian, Sofie Cambré, Laurent Cognet, Simon R. Corrie, Philip Demokritou, Silvia Giordani, Tobias Hertel, Tetyana Ignatova, Mohammad F. Islam, Nicole M. Iverson, Anand Jagota, Dawid Janas, Junichiro Kono, Sebastian Kruss, Markita P. Landry, Yan Li, Richard Martel, Shigeo Maruyama, Anton V. Naumov, Maurizio Prato, Susan J. Quinn, Daniel Roxbury, Michael S. Strano, James M. Tour, R. Bruce Weisman, Wim Wenseleers, Masako Yudasaka

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In a recent correspondence, the Swedish non-profit organization ChemSec announced the addition of carbon nanotubes to the SIN (‘Substitute It Now’) list1. Carbon nanotubes were added as an entire material class that “should be restricted or banned in the EU.” We believe that this recommendation confuses researchers and the public as it is based on evidence from a very narrow subset of data. Such a designation will likely hinder innovations that could lead to safe and effective applications of carbon nanotubes. Furthermore, this line of reasoning could damage other fields of science and technology, if applied similarly. We have worked …

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Improved Demo Of Granular Flow, Said Shakerin Mar 2020

Improved Demo Of Granular Flow, Said Shakerin

All Faculty Articles - School of Engineering and Computer Science

No abstract provided.

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Cal Poly Supermileage Dynamometer, Jacob Randall, Nate Deffenbaugh, Kyle Milgram Mar 2020

Cal Poly Supermileage Dynamometer, Jacob Randall, Nate Deffenbaugh, Kyle Milgram

Mechanical Engineering

Our senior project involves designing a chassis dynamometer capable of simulating variable loads for the Cal Poly Supermileage Vehicle (SMV) team. The chassis dynamometer we are developing uses an alternator to develop additional resistance that the vehicle will have to overcome while testing. To implement a control system for the variable load, we use an Arduino Nano paired with multiple sensors and drivers. This control system allows the user to select different levels of resistance that correlate with different road grades. We designed a custom Printed Circuit Board (PCB) that will contain all the electrical components needed for the control …

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Interoperable Ads-B Confidentiality, Brandon C. Burfeind Mar 2020

Interoperable Ads-B Confidentiality, Brandon C. Burfeind

Theses and Dissertations

The worldwide air traffic infrastructure is in the late stages of transition from legacy transponder systems to Automatic Dependent Surveillance - Broadcast (ADS-B) based systems. ADS-B relies on position information from GNSS and requires aircraft to transmit their identification, state, and position. ADS-B promises the availability of high-fidelity air traffic information; however, position and identification data are not secured via authentication or encryption. This lack of security for ADS-B allows non-participants to observe and collect data on both government and private flight activity. This is a proposal for a lightweight, interoperable ADS-B confidentiality protocol which uses existing format preserving encryption …

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Identifying And Positively Addressing Real And Perceived Barriers To Inclusion In Construction, Lisa Breitenfield Mar 2020

Identifying And Positively Addressing Real And Perceived Barriers To Inclusion In Construction, Lisa Breitenfield

The Professional Constructor

The construction industry is facing difficulties in recruiting and training new skilled workers. My essay will identify some methods companies and the AGC can use to attract new employees. Some potential solutions involve encouraging schools to expose students to the construction industry, recognizing and assisting working parents with childcare issues, companies offering employees personalized career advancement schedules, and recruiting students focused on the arts and history for detail oriented roles in the industry. The Associated General Contractors can help by advising individual companies on attracting employees and facilitate greater mentorship programs between companies and educational institutions.

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Current State Of The Employee Assessment Process In The Construction Industry For Southeast United States, Dhaval Gajjar, Shima Clarke, Cayla Anderson Mar 2020

Current State Of The Employee Assessment Process In The Construction Industry For Southeast United States, Dhaval Gajjar, Shima Clarke, Cayla Anderson

The Professional Constructor

The employee assessment process (EAP) is a formal evaluation system used by an employer to evaluate employee’s performance and behavior within a company. The objective of this paper is to determine the current state of the most common used practices for EAP in the construction industry; specifically in Southeast United States. Existing literature was reviewed to understand the historical context and the current documentation of existing EAP processes in other industries and within the construction industry. Literature revealed that there is no formal standardized process documented for EAP practice within the United States construction industry. Based on the literature findings …

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State Department Of Transportation Suas Program Development And Operational Deployment, Dennis Bausman, Joseph Burgett, Ajay Jadhav, Scott Shaffer, Eric Stuckey Mar 2020

State Department Of Transportation Suas Program Development And Operational Deployment, Dennis Bausman, Joseph Burgett, Ajay Jadhav, Scott Shaffer, Eric Stuckey

The Professional Constructor

Over the past several years small unmanned aircraft systems (sUAS) have gained popularity in the private sector. Recent studies have shown an increasing interest from state DOTs in the U.S. for the use of drone technology. However, most of the studies did not fully investigate the depth of program integration or application. This study combines the findings of recent studies to identify state DOTs with the most extensive sUAS operational experience. The drone champions for the six states identified, were interviewed to gain substantive insight regarding program initiation and organization, the spectrum of agency use, perceived benefits, and the DOT’s …

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Increasing Diversity And Inclusion Through Mentoring Underrepresented Groups, Corban Williams Mar 2020

Increasing Diversity And Inclusion Through Mentoring Underrepresented Groups, Corban Williams

The Professional Constructor

The Construction Industry historically has struggled to gain traction with underrepresented groups, such as women, African-Americans, and the Hispanic/ Latinx community. To combat this, industry-wide action is necessary to increase diversity and inclusion. Underrepresented communities have misconceptions about the construction industry including a lack of knowledge about the wide range of possible careers. By the AGC establishing a mentoring program with career goals and psychological attributes for grades 6-12 and college students, a positive dialog about the industry would be established. Visibility and promotion of the program would encourage students of underrepresented communities to consider a career in the construction …

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Perspectives On Diversity And Inclusion In Construction, Anna A. Pasha Mar 2020

Perspectives On Diversity And Inclusion In Construction, Anna A. Pasha

The Professional Constructor

The construction industry is rapidly growing and contractors are optimistic about the immediate and long-term growth of the industry. As demand increases, the construction industry faces a projected labor shortage crisis. As the construction industry grows, it must rise to meet the challenge of solving this labor shortage by diversifying and widening its labor pool and strategically attracting new talent. This essay offers a detailed solution that includes a redefinition of approaches to diversity, ideas for short-term policies and creative long-term policies, and a lasting vision for the industry that will guide us to continue growing progressively and avoiding crises …

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Examining The Pre-Construction Professional: Career Evolution, Responsibilities And Skilles, Aaron D. Sauer, Hariharan Naganathan, Kevin M. Hubbard Mar 2020

Examining The Pre-Construction Professional: Career Evolution, Responsibilities And Skilles, Aaron D. Sauer, Hariharan Naganathan, Kevin M. Hubbard

The Professional Constructor

The construction industry is constantly evolving to meet the needs of clients in light of significant technological and regulatory change. The Pre-Construction Professional is one example of a new career path that has emerged in response to changing market conditions. This study investigated the Pre-Construction Professional in an effort to define when the career path emerged and why it was needed. The researchers also sought to describe the role of the Pre-Construction Professional and document their requisite knowledge and skills. The research design was based on extensive interviews with working Pre-Construction Professionals and supported by available literature. The findings of …

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Assessing The Equity Gap In Construction Education, Jared M. Burgoon, John Killingsworth, Jonathan W. Elliott, Molly M. Weisshaar Mar 2020

Assessing The Equity Gap In Construction Education, Jared M. Burgoon, John Killingsworth, Jonathan W. Elliott, Molly M. Weisshaar

The Professional Constructor

There is a documented demand for an educated construction management workforce. To help meet this demand, construction education programs at numerous post-secondary institutions have established objectives and goals to recruit, train, and graduate high-quality students; and, many of these programs are charged with providing educational opportunities to students who have been traditionally underserved in higher education (e.g., female, minority, first generation students, etc.). This study compared the enrollment and retention rates, interdepartmental migration patterns, and student satisfaction and graduation success outcomes of undergraduate students enrolled in a CM program at a public university as a means of identifying trends and …

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Use Of Body Composition Imaging To Calculate 3-D Inertial Parameters For Inverse Dynamic Analysis Of Youth Pitching Arm Kinetics, Dalton James Jennings Mar 2020

Use Of Body Composition Imaging To Calculate 3-D Inertial Parameters For Inverse Dynamic Analysis Of Youth Pitching Arm Kinetics, Dalton James Jennings

Master's Theses

The objectives of this study were to 1) calculate participant-specific segment inertial parameters using dual energy X-ray absorptiometry (DXA) data (referred to as full DXA-driven parameters) and compare the pitching arm kinetic predictions using full DXA-driven inverse dynamics vs scaled, DXA mass-driven (using DXA masses but scaled centers of mass and radii of gyration), and DXA scaled inverse dynamics(ID) (using the full DXA-driven inertial parameters averaged across all participants), 2) examine associations between full DXA-driven kinetics and body mass index (BMI) and 3) examine associations between full DXA-driven kinetics and segment mass index (SMI). Eighteen 10- to 11- year-olds pitched …

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Subject-Specific Finite Element Models Of The Human Knee For Transtibial Amputees To Analyze Tibial Cartilage Pressure For Gait, Cycling, And Elliptical Training, Jonathon Stearns Mar 2020

Subject-Specific Finite Element Models Of The Human Knee For Transtibial Amputees To Analyze Tibial Cartilage Pressure For Gait, Cycling, And Elliptical Training, Jonathon Stearns

Master's Theses

It is estimated that approximately 10-12% of the adult population suffers from osteoarthritis (OA), with long reaching burdens personally and socioeconomically. OA also causes mild discomfort to severe pain in those suffering from the disease. The incidence rate of OA for individuals with transtibial amputations is much than average in the tibiofemoral joint (TF). It is well understood that abnormal articular cartilage stress, whether that be magnitude or location, increases the risk of developing OA. Finite element (FE) simulations can predict stress in the TF joint, many studies throughout the years have validated the technology used for this purpose. This …

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Design And Implementation Of Stewart Platform Robot For Robotics Course Laboratory, Trent R. Peterson Mar 2020

Design And Implementation Of Stewart Platform Robot For Robotics Course Laboratory, Trent R. Peterson

Master's Theses

A Stewart Platform robot was designed, constructed, and programmed for use in Cal Poly’s ME 423 Robotics: Fundamentals and Applications laboratory section. A Stewart Platform is a parallel manipulator robot with six prismatic joints that has six degrees of freedom, able to be defined in both position and orientation. Its purpose is to supplement parallel robot material covered in lecture. Learning objectives include applying and verifying the Stewart Platform inverse kinematics and investigating the Stewart Platform’s operation, range of motion, and limitations. The Stewart Platform geometry and inverse kinematics were modeled and animated using MATLAB. The platform was then built …

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Over Height Impact Avoidance And Incident Detection System, Suvash Chapain, Aly Mousaad Aly Mar 2020

Over Height Impact Avoidance And Incident Detection System, Suvash Chapain, Aly Mousaad Aly

Faculty Publications

During the construction and repair of bridges, work platforms or construction-related containment may result in restricted vertical clearances at a work location. Some tractor-trailer combinations are prone to over-height collisions at these locations. Collisions are a hazard to all drivers, and repair of the damage typically causes traffic delays. Appropriate solutions to this problem will focus on the prevention of collisions by detecting over-height vehicles and directing the drivers to take an alternate safe route. This presentation addresses the design and functionality of smart detection/alert systems that can be set up well in advance of a known vertical clearance restriction …

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Effect Of Fiber Reinforced Polymer Tubes Filled With Recycled Materials And Concrete On Structural Capacity Of Pile Foundations, Visar Farhangi, Moses Karakouzian Mar 2020

Effect Of Fiber Reinforced Polymer Tubes Filled With Recycled Materials And Concrete On Structural Capacity Of Pile Foundations, Visar Farhangi, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

This paper deals with analyzing the structural responses of glass-fiber-reinforced polymer (GFRP) tubes filled with recycled and concrete material for developing composite piles, as an alternative to traditional steel reinforced piles in bridge foundations. The full-scale GFRP composite piles included three structural layers, using a fiber-oriented material that was inclined longitudinally. Almost 60% of the fibers were orientated at 35° from the longitudinal direction of the pile and the rest 40 percent were oriented at 86° from the horizontal axis. The segment between the inner and outer layers was inclined 3° from the hoop direction in the tube. The behavior …

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Optimizing Llrf Parameters In The Electron-Ion Collider, William M. Bjorndahl Mar 2020

Optimizing Llrf Parameters In The Electron-Ion Collider, William M. Bjorndahl

Physics

To improve particle interaction in the future Electron-Ion Collider (EIC), we investigated different feedback implementations to control the accelerating voltage and examined the power and beam phase for each instance. Using MATLAB, we studied three feedback mechanisms: Direct, One Turn, and Feedforward. Enacting feedforward yielded the best performance. To minimize the klystron power consumption, we analyzed different Low-Level Radio Frequency (LLRF) parameters such as detuning. Combining theory and simulated results, we found the optimal detuning value that minimizes klystron power consumption.

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Residual Strength Of Franciscan-Derived Clay, Yingyi Xu Mar 2020

Residual Strength Of Franciscan-Derived Clay, Yingyi Xu

Master's Theses

In February of 2017 after a period of heavy rainfall, a slope destabilized behind Fremont Hall on the campus of Cal Poly San Luis Obispo. The geology of this slope stability failure is the Franciscan Complex. The Franciscan Complex, when weathered in place, results in clay soil that makes up the typical soil mantle on the hills throughout the region. Peak strength is the typical parameter tested to assess the strength of the soil. For the Franciscan-derived clay, the residual strength is the focus of this study to understand slope failure since the clay is the weakest portion of the …

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Lip Thrust Apparatus, Ian M. Wilson, Alvin K. Cheong Mar 2020

Lip Thrust Apparatus, Ian M. Wilson, Alvin K. Cheong

Mechanical Engineering

This document contains the background information, defined scope of work, preliminary design philosophy, conceptual design development, and final design choices along with its corresponding manufacturing and design verification plans. It also includes the preliminary testing and prototyping necessary in bringing our verification prototype to its final configuration for delivery. Finally, it includes the entire manufacturing process followed in creating the final project and the extensive testing performed to ensure it meets the defined engineering specifications. The aerodynamic phenomenon being analyzed and demonstrated in our final deliverable can be seen in a scenario where when a propeller is enclosed in a …

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An Economic And Ecological Analysis Of Three Land Building Approaches Using Mississippi River Sediment, Madison Hasenkampf Mar 2020

An Economic And Ecological Analysis Of Three Land Building Approaches Using Mississippi River Sediment, Madison Hasenkampf

Honors Capstones

No abstract provided.

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Diy Incubator, Aryan Zia, Grace Spurlock, Garrett Janney Mar 2020

Diy Incubator, Aryan Zia, Grace Spurlock, Garrett Janney

Biomedical Engineering

This project report provides detailed information on designing and building a DIY Incubator. The device is indicated for growing and maintaining BSL-1 mammalian or bacterial cell culture with a temperature control in the range of 25-45°C ± 1°C. The device is made fully programmable via an Arduino, and is structurally designed to fit two T75 cell culture flasks at a time. The device is able to return to a specified temperature set point within 10 minutes and maintains 5% CO2 partial pressure conditions. The incubator has a small physical footprint, with an overall dimension of 22in x 16in x 15.5in …

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Selection Of Blowing Agent For Metal Foam Production: A Review, Ankur Bisht, Brijesh Gangil, Vinay Kumar Patel Mar 2020

Selection Of Blowing Agent For Metal Foam Production: A Review, Ankur Bisht, Brijesh Gangil, Vinay Kumar Patel

Journal of Metals, Materials and Minerals

Metal foams are cellular solids in which gas is uniformly distributed throughout the metal matrix. One of the cheapest ways of evolving the gas is introducing the blowing agent in parent metal in liquid state. A blowing agent is defined as a material that decomposes under the presence of heat and releases gas which then propels the foaming process. The quality of final foam is influenced by several parameters such as composition, size and volume fraction of the blowing agent used. Different chemicals which can evolve gases such as carbonates and metal hydrides fit into the description of blowing agent. …

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An Approach To Search The Potentiality Of Node In Bamboo Strip Reinforced Composites, Mohammad Irfan Iqbal, Rashed Al Mizan, Ayub Nabi Khan Mar 2020

An Approach To Search The Potentiality Of Node In Bamboo Strip Reinforced Composites, Mohammad Irfan Iqbal, Rashed Al Mizan, Ayub Nabi Khan

Journal of Metals, Materials and Minerals

Bamboo has recently entered the composite sector with some attractive labels such as 'green'. The current commercial manufacturing method of bamboo composite removes the node's portion of bamboo culm during bamboo processing. This method generates a high amount of solid waste materials along with processing complexity and the scientific merit of this practice is also questionable. This research investigates the effects of culm nodes on bamboo based composite properties. In this study an approach to produce bamboo strips reinforced epoxy composites and their mechanical properties (e.g. tensile, flexural and impact properties) were reported. It was demonstrated that mechanical properties of …

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Preparation And Characterization Of Lake Pigments From Sappan Wood Using Thai Local Clays, Jitnapa Sirirak, Nattawan Worawannotai, Cheewita Suwanchawalit, Supanee Chayabutra Mar 2020

Preparation And Characterization Of Lake Pigments From Sappan Wood Using Thai Local Clays, Jitnapa Sirirak, Nattawan Worawannotai, Cheewita Suwanchawalit, Supanee Chayabutra

Journal of Metals, Materials and Minerals

Thai local clays: Munpoo clay (MC) and Dindang clay (DC) were utilized as the adsorbents for preparation of the lake pigments from sappan wood. The lake pigment which was prepared by using MC as the adsorbent (L-MC) appeared reddish-brown while a deeper reddish-brown color of the lake pigment (L-DC) was obtained by using DC as the adsorbent. Characterization of MC, DC, L-MC, and L-DC was accomplished by XRD, SEM, FT-IR, BET, TGA and UV-Vis DRS. The effects of adsorbent dosage, pH of sappan wood extract and time on the adsorption were also investigated. The results revealed that silicon oxide and …

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Poly(Ester Urethane)-Crosslinked Carboxymethylchitosan As A Highly Water Swollen Hydrogel, Nunthiya Deepuppha, Apiwat Kadnaim, Boonjira Rutnakornpituk, Metha Rutnakornpituk Mar 2020

Poly(Ester Urethane)-Crosslinked Carboxymethylchitosan As A Highly Water Swollen Hydrogel, Nunthiya Deepuppha, Apiwat Kadnaim, Boonjira Rutnakornpituk, Metha Rutnakornpituk

Journal of Metals, Materials and Minerals

This work focused on the synthesis and characterization of carboxymethylchitosan (CMC)-based hydrogels modified with polyester-containing polyurethane (PU). The polyester was first synthesized from the condensation between 1,6-hexane diol and malonic acid, then reacted with an excess of 1,6-hexamethylene diisocyanate (HDI), and followed by the reaction with ethylene glycol as a chain extender to gain PU. CMC was chemically crosslinked with a water soluble crosslinker in the presence of 1-60 wt% of PU to obtain highly water swollen CMC hydrogels. Upon addition of PU, the CMC hydrogel showed excellent water swellability (up to 400 times of the dried weight), and it …

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The Luminescence, Optical, And Structural Properties Of Srmoo4:Ce3+ Phosphor For Photonics Material Applications, Eakgapon Kaewnuam, Nuanthip Wantana, Sasithorn Saikaew, Jakrapong Kaewkhao Mar 2020

The Luminescence, Optical, And Structural Properties Of Srmoo4:Ce3+ Phosphor For Photonics Material Applications, Eakgapon Kaewnuam, Nuanthip Wantana, Sasithorn Saikaew, Jakrapong Kaewkhao

Journal of Metals, Materials and Minerals

SrMoO4:Ce3+ phosphors with different Ce2O3 concentration were studied in the structure, optical and luminescence properties. The phosphor powders were synthesized by a solid-state reaction to investigate with the XRD, FTIR, absorption and emission spectra measurement. The XRD patterns confirm the tetragonal crystalline structure of SrMoO4 host composition. The FTIR spectra show the dominant vibrations of tetrahedral [MoO4]2- unit in powders. These phosphors absorb photons in the range of ultraviolet and visible light proved by the absorption spectra. The emission spectra represent the strongest emission at 421 nm wavelength of phosphors under 266 nm excitation. This emission occurred under the transition …

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Defects Of The Steel Billet In Continuous Casting, Anh-Hoa Bui, Van-Hung Nguyen Mar 2020

Defects Of The Steel Billet In Continuous Casting, Anh-Hoa Bui, Van-Hung Nguyen

Journal of Metals, Materials and Minerals

In continuous casting process, defects of the steel billet (e.g. crack, pinhole, blowhole, central shrinkage, slag entrapment and appearance deviation, etc.) negatively affect the quality and the yield of rolled products. This research has been carried out to investigate some defects which often occurred in Vietnamese steel plants. The experimental work was conducted in an industrial 4-strands continuous casting machine with the billet's cross-section of 130×130 mm2 . The position, generating cause identification of these defects and proper measures have been discussed. A change in the steel compositions and the water distribution during secondary cooling was applied to improve the …

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