A Density Functional Theory Study On Using Montmorillonite To Reduce Air Pollution,
2020
Nuclear Physics and Biophysics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung 40132, Indonesia
A Density Functional Theory Study On Using Montmorillonite To Reduce Air Pollution, Triati Dewi Kencana Wungu, Meqorry Yusfi, Suprijadi Suprijadi
Makara Journal of Technology
In this study, density functional theory (DFT) method is used to investigate the possibility of using a smectite clay mineral called montmorillonite (MMT) in reducing heavy metals, such as Cd, through Cd adsorption. The mechanism of Cd adsorption in MMT is observed theoretically, and the tetrahedrally isomorphic substitution on the upper layer of MMT is considered to observe the role of Al and Fe in strengthening Cd adsorption. Two types of MMT are modeled in this study: Al-MMT and Fe-MMT. The Al-MMT means that Al substitutes one atom in the upper tetrahedral layer of MMT, while Fe-MMT means that Fe …
Ionic Conductiviy Of Alginate-Nh4cl Polymer Electrolyte,
2020
Ionic Materials Team, Faculty of Industrial Science & Technology, Universiti Malaysia, Pahang 26300, Malaysia
Ionic Conductiviy Of Alginate-Nh4cl Polymer Electrolyte, Nurhasniza Mamajan Khan, Noor Saadiah Mohd Ali, Ahmad Faizrin Ahmad Fuzlin, Ahmad Salihin Samsudin
Makara Journal of Technology
This study aims to produce a solid biopolymer electrolyte (SBE) by doping ammonium chloride (NH4Cl) into alginate. Solution casting was used to prepare the alginate–NH4Cl SBE system. Electrical impedance spectroscopy was performed to analyze the electrical properties of the SBE under the applied frequency range of 50 Hz–1 MHz. The incorporation of 8 wt.% NH4Cl enhances the ionic conductivity of the SBE up to 3.18 × 10-7 S/cm at ambient room temperature. Fourier transform infrared spectroscopy shows that complexation occurs between the hydroxyl (-OH), carboxylate (COO-) and ether linkage (C-O-C) functional groups due to the formation of inter- and intra-molecular …
Use Of Viscoplastic Damper For Improving The Resistance Of Steel Frames To Blast Loading,
2020
Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol 47148-71167, Iran
Use Of Viscoplastic Damper For Improving The Resistance Of Steel Frames To Blast Loading, Gholamreza Abdollahzadeh, Hadi Faghihmaleki, Hamed Hamidi Jamnani, Atefeh Ebrahimi Bardar
Makara Journal of Technology
In this paper, we evaluated the effect of viscoplastic dampers on the response of steel frames under blast loading. We used SAP2000 software and link elements to investigate the responses of nine-story steel frames with and without dampers. The proposed viscoplastic damper is a new type of viscous damper. The application of this damper is based on the availability of its constituent materials. The damper acts as a viscoelastic damper at low levels of vibration, but it acts as a combination of viscoelastic operator and metal-yielding device at extreme levels of vibration. With respect to the height of the structure, …
Influence Of Lithium Bromide On Electrical Properties In Bio-Based Polymer Electrolytes,
2020
Ionic Materials Team, Faculty of Industrial Sciences & Technology, Universiti Malaysia Pahang, Pahang 26300, Malaysia
Influence Of Lithium Bromide On Electrical Properties In Bio-Based Polymer Electrolytes, Ahmad Faizrin Fuzlin, Bouchta Sahraoui, Ahmad Salihin Samsudin
Makara Journal of Technology
This research presents the influence of lithium bromide (LiBr) on the electrical properties of alginate in bio-based polymer electrolytes (BBPEs) system. Bio-based alginate was prepared using the solution casting technique with various LiBr compositions. The ionic conductivity and electrical properties of the prepared BBPEs samples were studied using electrical impedance spectroscopy over a frequency range of 50 Hz–1 MHz. A maximum ionic conductivity of 7.46 × 10−5 S cm-1 was obtained for a sample containing 15 wt. % lithium bromide-doped alginate BBPEs at ambient temperature (303 K). The electrical analysis revealed that the most conductive sample based on alginate-LiBr BBPEs …
Mechanical Alloying-Assisted Coating Of Fe–Al Powders On Steel Substrate,
2020
Nano Center Indonesia, PUSPIPTEK, Banten 15314, Indonesia
Mechanical Alloying-Assisted Coating Of Fe–Al Powders On Steel Substrate, Alfian Noviyanto, Sri Harjanto, Wahyu Bambang Widayatno, Agus Sukarto Wismogroho, Muhamad Ikhlasul Amal, Nurul Taufiqu Rochman
Makara Journal of Technology
The coating layer of Fe–Al powders on the steel substrate was prepared by mechanical alloying at room temperature. Fe, Al, and the steel substrates were milled with high-energy ball milling for 32 h with a ball-to-powder ratio of 8 in an argon atmosphere to prevent oxidation during milling. Although mechanical alloying was performed for 32 h, no new phases were observed after mechanical alloying, as analyzed by X-ray diffraction. However, the crystallite size of the milled powders for 32 h decreased by factor two compared with the initial powders. Scanning electron micrographs showed that the coating layers formed >8 h …
Performance Of Free-Space Optical Communication Systems Using Optical Amplifiers Under Amplify-Forward And Amplify-Received Configurations,
2020
Informatics Engineering, Faculty of Information and Communications Technology, Universitas Nasional, Jakarta 12520, Indonesia
Performance Of Free-Space Optical Communication Systems Using Optical Amplifiers Under Amplify-Forward And Amplify-Received Configurations, Ucuk Darusalam, Arockia Bazil Raj, Fitri Yuli Zulkifli, Purnomo Sidi Priambodo, Eko Tjipto Rahardjo
Makara Journal of Technology
With the growth of digital technology in the stage of industrial revolution 4.0, the demand for broadcasting large amounts of information to last mile users has increased. Free-space optical (FSO) communication is one of the telecommunication platforms that has shown immense potential in meeting the demand for information broadcasting. In this work, the performance of FSO communication based on wavelength division multiplexing with a data rate of 80 Gbps is investigated through simulations. The configuration of optical amplifiers in the FSO system is set up on the basis of the amplify-forward and amplify-received configurations to expand the network. The investigation …
Iso 9001:2015 Risk-Based Thinking: A Framework Using Fuzzy-Support Vector Machine,
2020
Electronics Engineering Technology, Technological University of the Philippines, Manila 1000, Philippines
Iso 9001:2015 Risk-Based Thinking: A Framework Using Fuzzy-Support Vector Machine, Ralph Sherwin A. Corpuz
Makara Journal of Technology
Risk-based thinking (RBT) is one of the distinct new features of the International Organization for Standardization 9001:2015. Interestingly, the standard does not prescribe any tools. Hence, organizations are puzzled as to the extent of conformance. Some organizations have adopted formal tools. However, these tools seem insufficient in linking the standard into an evidence-based decision support system. To resolve gaps in RBT implementation, this paper proposes a framework based on fuzzy inference system (FIS) and support vector machine (SVM) to automate risk analysis and evaluation, proposal and verification of action plans, and prediction of the feasibility of risks and opportunities according …
Ccfss Technical Bulletin Fall 2020, Vol. 21, Number 2,
2020
Missouri University of Science and Technology
Ccfss Technical Bulletin Fall 2020, Vol. 21, Number 2, Wei-Wen Yu Center For Cold-Formed Steel Structures
CCFSS Technical Bulletins (1993 - 2020)
No abstract provided.
Ccfss Technical Bulletin Fall 2020, Vol. 21, Number 1,
2020
Missouri University of Science and Technology
Ccfss Technical Bulletin Fall 2020, Vol. 21, Number 1, Wei-Wen Yu Center For Cold-Formed Steel Structures
CCFSS Technical Bulletins (1993 - 2020)
No abstract provided.
Experimental Testing Of A Lightly Reinforced Concrete Shear Wall,
2020
California Polytechnic State University, San Luis Obispo
Experimental Testing Of A Lightly Reinforced Concrete Shear Wall, Jerry Hue Truong Luong, Rory Sebastian De Sevilla
Architectural Engineering: Graduate Reports
This project report summarizes the findings of a half-scale laboratory test on a slender lightly reinforced concrete (LRC) shear wall subjected to cyclic loading. LRC shear walls, specifically those of pre-1980’s type design, have longitudinal and horizontal reinforcement ratios near the code minimum, while often lacking confinement in the wall end-zones. These walls are thought to exhibit brittle compressive failure mechanisms such as rebar buckling or concrete crushing based on observations from past earthquakes. Non-ductile concrete buildings are a large contributor to earthquake losses around the globe, as noted in the San Fernando (1971) and Christchurch (2011) earthquakes, to name …
Wei-Wen Yu Center For Cold-Formed Steel Structures (1990-2020),
2020
Missouri University of Science and Technology
Wei-Wen Yu Center For Cold-Formed Steel Structures (1990-2020), Roger A. Laboube, Wei-Wen Yu
American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)
Final Report: Wei-Wen Yu Center For Cold-Formed Steel Structures
Seismic Loading Effects Within Orthogonally Connected Steel Lateral Force Resisting Systems,
2020
University of Arkansas, Fayetteville
Seismic Loading Effects Within Orthogonally Connected Steel Lateral Force Resisting Systems, Alhussin Faraj Aliwan
Graduate Theses and Dissertations
Steel buildings located within seismically active regions require special design considerations to ensure public safety and prevent collapse during an extreme seismic event. Two commonly used steel systems are special moment frames (SMFs) and buckling-restrained braced frames (BRBFs). When two seismic systems share a common column in an orthogonal configuration (such as at a building corner), design specifications currently consider a 100+30 rule wherein the shared column is designed for 100% fuse demand in one direction, plus 30% fuse demand from the other direction. While this rule has been shown to be reasonable for elastic building response, a few studies …
Using Bcsa Cement To Repair Waterway Transportation Structures,
2020
University of Arkansas, Fayetteville
Using Bcsa Cement To Repair Waterway Transportation Structures, Anazaria Johanis Ortega Gonzalez
Graduate Theses and Dissertations
Many maritime structures (e.g., locks, dams, ports) in the US are either reaching or are past their design lives, and there are limited funds for the necessary maintenance activities which can lead to repairs that requires closures. These structures are not easy to detour and often require dewatering before repairs can be made, closures can cause delays and business-related losses which can have a large effect on the nation’s economy. Thus, it is advantageous to reduce the repair time for maritime structures. BCSA (belitic calcium sulfoaluminate) cement is a promising material to perform this type of repair due to its …
Comparison Of Additively Manufactured And Wrought 17-4 Ph Stainless Steels In Ultra Low Cycle Fatigue,
2020
University of Arkansas, Fayetteville
Comparison Of Additively Manufactured And Wrought 17-4 Ph Stainless Steels In Ultra Low Cycle Fatigue, Timothy Strasser
Graduate Theses and Dissertations
Additive manufacturing (AM) processes allow for creation of complex geometries that are otherwise impractical to fabricate with traditional subtractive methods. AM technology has potential to improve the optimization of seismic lateral force resisting components which dissipate seismic energy through large plastic strains; however, the ultra low-cycle fatigue performance of AM metals are not yet well understood. Void formation during the AM fabrication process has potential to affect performance. This study compares the performance of heat-treated and non-heat-treated AM and wrought 17-4PH stainless steel in Ultra Low Cycle Fatigue. To understand ULCF performance differences between the AM and wrought specimens, post …
Behavior Of Concrete Structures Reinforced With High Strength Steel,
2020
University of Arkansas, Fayetteville
Behavior Of Concrete Structures Reinforced With High Strength Steel, Rahman S. Kareem
Graduate Theses and Dissertations
The structural strength and corrosion resistance of concrete members are improved when A1035 steel is used as the main reinforcement. The enhancement of A1035 is achieved by the modification of the composition and microstructure of the steel. Therefore, the behavior of concrete structures reinforced with high-performance steel (A1035) is different from those reinforced with the regular steel (A615). Concrete bridge decks reinforced with different amounts of A1035 were studied in this research program. The structural behavior of twelve concrete bridge decks reinforced with A615 Grade 420 (60 ksi) and A1035 Grade 830 (120 ksi) steel was investigated at both service …
Moisture Monitoring Of A Clt Structure In A Southern Climate,
2020
University of Arkansas, Fayetteville
Moisture Monitoring Of A Clt Structure In A Southern Climate, Elizabeth Poblete
Graduate Theses and Dissertations
Understanding of moisture behavior in cross laminated timber (CLT) is critical to the widespread use of CLT in construction in the United States. Currently, very little data exists on the long-term impact of moisture on CLT. The objective of this research is to collect data regarding the long-term moisture variation in the CLT panel at the University of Arkansas Adohi Hall residence hall. The climate of Northwest Arkansas is different from previously monitored buildings, as they were in the Pacific Northwest. Comparatively, Northwest Arkansas has a warmer climate with higher average annual precipitation. Waterproofing efforts are usually employed to prevent …
Innovative Approach To Repair Corroded Steel Piles Using Ultra-High Performance Concrete,
2020
Missouri University of Science and Technology
Innovative Approach To Repair Corroded Steel Piles Using Ultra-High Performance Concrete, Binod Shrestha, Ahmed Gheni, Mohanad M. Abdulazeez, Mohamed Elgawady
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Steel H-piles are a common structural system in existing bridges. Many steel H-piles have been corroded as a result of severe weather and acid/alkaline salt exposures, causing a reduction in the axial load capacity. This paper experimentally investigates the use of ultra-high performance concrete (UHPC) encasement as a novel repair method for corroded steel H-pile. UHPC displays better tensile strength, early compressive strength, workability, and durability compared with conventional concrete. The proposed repair is used to bridge the corroded section in H-pile using either a cast-in-place or precast UHPC elements. A series of push-out tests was conducted on eight full-scale …
Bond Behavior Between Steel Fiber Reinforced Polymer (Srp) And Concrete,
2020
Missouri University of Science and Technology
Bond Behavior Between Steel Fiber Reinforced Polymer (Srp) And Concrete, Xingxing Zou, Lesley Sneed
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Steel fiber reinforced polymer (SRP) composite materials, which consist of continuous unidirectional steel wires (cords) embedded in a polymeric matrix, have recently emerged as an effective solution for strengthening of reinforced concrete (RC) structures. SRP is bonded to the surface of RC structures by the same matrix to provide external reinforcement. Interfacial debonding between the SRP and concrete is a primary concern in this type of application. This study aimed to investigate the bond characteristics between SRP and concrete determined by single-lap direct shear tests with different composite bonded lengths and fiber sheet densities (cord spacings). Specimens with medium density …
Tensile Behavior Of Frp Anchors Made From Cfrp Ropes Epoxy-Bonded To Uncracked Concrete For Flexural Strengthening Of Rc Column,
2020
Portland State University
Tensile Behavior Of Frp Anchors Made From Cfrp Ropes Epoxy-Bonded To Uncracked Concrete For Flexural Strengthening Of Rc Column, Yasir Saeed, Wisam Amer Aules, Franz N. Rad, Anis M. Raad
Civil and Environmental Engineering Faculty Publications and Presentations
One of the major problems with using fiber reinforced polymer (FRP) in strengthening reinforced concrete (RC) structures is FRP premature debonding. Anchoring FRP materials to concrete has become associated with most of the strengthening techniques. One of the anchoring techniques is using handmade anchors made from FRP materials. In previous studies, most FRP anchors were made from rolling pre-cut FRP sheets and had short embedment (mm) as they were used for flexural or shear strengthening of RC beams. In the present study, FRP anchors were made from carbon fiber reinforced polymer (CFRP) ropes and had long embedment to be used …
Tanzanian Concrete Masonry Walls,
2020
California Polytechnic State University, San Luis Obispo
Tanzanian Concrete Masonry Walls, Edward J. Kaminski
Architectural Engineering
Walls that replicate masonry walls used in Tanzania are constructed and tested. The results from testing was compared with the respective predictions made using code guidelines from ASCE 7 and TMS 402.
