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Study of Zwitterionic Homopolymer Polysulfobetaine and Gel Properties in Various Solutions of Different Anion Species and Cation Valences
Get PDFZwitterionic homopolymer polysulfobetaine (PBET) gels were synthesized using free radical polymerization. The effect of temperatures on adsorption behavior of the gel and transition temperature of the polymer in various solutions of LiCl, KCl, NaCl, Al(NO3)3, Zn(NO3)2, and NaNO3 were studied. The tendency of poly(BET)s transition temperature in Cl solutions very identical. All of poly(BET) solution resulted in Upper Critical Temperature (UCST). Its number increased along with the elevation of salt concentration. The number declined again when the concentration was too high. BET gel successfully adsorbed various ions with the amount of adsorption tendency of LiCl < NaCl < KCl
Pemanfaatan Ekstrak Kulih Buah Langsat sebagai Inhibitor Organik Korosi Pada Baja ST 37 dalam Media IM H2S04
Get PDFKorosi adalah kerusakan atau kehancuran yang disebabkan oleh reaksi kimiawi material di lingkungannya.Salah satu cara untuk mengurangi laju korosi yaitu dengan penggunaan inhibitor organik. Penghambat korosi adalahzat kimia yang bila ditambahkan ke lingkungan dapat mengurangi laju korosi logam di lingkungan. Kulit buah langsat(Lansium domesticum var. Pubescens) adalah inhibitor yang akan digunakan. Dalam penelitian ini menggunakan bajaST 37 dengan media H2SO4 1M dengan variasi konsentrasi 0, 3, 5 dan 11 mg. Metode ekstraksi yang digunakan adalahmetode maserasi. Pada uji Tafel nilai laju korosi sebesar 3,3738 mmpy tanpa inhibitor dan dengan inhibitor mencapai1,7471 mmpy serta dihasilkan juga efisiensi inhibisinya sebesar 48,21%. Menghasilkan efisiensi pengujian weight lossinhibisi sebesar 53,9
Risk Management in the Metal Casting Industry: Case in Ceper Klaten
Get PDFThis study investigates the implementation of risk management in the metal casting industry. Previous research examines risk management in the production process, while this research identifies risk management in business processes. The research sample is 68 companies incorporated in Batur Jaya cooperatives, Ceper Klaten. This research uses survey method. Business risk management consists of four dimensions: business strategic risk, operational risk, reporting risk and regulatory risk. The results showed that the implementation of business strategic risk, operational risk and reporting risk were good enough. The implementation of regulatory risk management is the lowest compared to the other three risk management dimensions
Effect of HAp on Characterization of MgZn-xHAp Biocomposites
Get PDFResearch on Mg as biodegradable materials in orthopedics has been carry out intensively in the 17 years. Various studies conducted to produce material that is superior in mechanical properties and corrosion resistance. One of the developments carry out is to make Mg-based composite. This study aims to see the effect of HAp on Mg6ZnHAp composites. The biocomposites were synthesized by mixing the HAp powder on the Mg6Zn powder mixture with the composition of 5%, 7% and 9% using ball milling for 30 minutes. The material is sintered at 350 oC and held for one hour. Biocomposites were characterized by SEM/EDS, X-ray diffraction (XRD) and Potentiostat. The SEM/EDS results showed that the larger the HAp composition resulted in the smaller grain size. The crystallite size of the material decreases with increasing HAp composition in the material. The presence of HAp in the material also affects the corrosion rate. The greater HAp composition in the material will result in better corrosion resistance.
Effect of Main Engine Placement and Propeller Shaft Inclination on Ship Performance
Get PDFPlacement of the ship propulsion system components might also affect the value of the ship's resistance and thrust. Included in the placement of the ship's propulsion system components are the placement of the main engine and propeller shaft inclination. Changes in the placement of the main engine will affect the location of the center of gravity of the ship which affects the trim and the amount of resistance of the ship. While propeller shaft inclination will affect the direction of thrust produced by the propeller. In this research, an analysis of how big the effect of the placement of the main engine and the propeller shaft inclination on various angles for the 60 GT fishing vessel on the ship's performance by using simulation. Simulations were performed with Numeca Fine Marine software using the Actuator Disk Propeller method. Propeller shaft inclination variations are 1⁰, 2⁰, 3⁰, and 4⁰. At each propeller shaft inclination, there are two variations of the placement of the main engine at a distance of 4m-6.5m from the AP and 5.5m-8m from the AP. Based on the results of the simulation that has been done, the greater the angle of the propeller shaft inclination, the more resistance value will be even smaller, and the thrust produced is also smaller. When the main engine is shifted towards FP, the resistance value will be greater, and the thrust generated is also greater. The most optimal conditions are on the rake of the propeller shaft 4⁰ and the main engine position 4m-6.5m from the AP, the total resistance value of the ship = 9648.97 N and the thrust = 16520.66, torque = 1867.46, KT = 0.1569, KQ = 0.0177, J = 0.2827 and propulsion efficiency = 0.3991. This configuration was chosen because to make the ship move at the same speed, the configuration requires less power
Analysis of Noise and Vibration on Single Cylinder Four Stroke Engine with Green Diesel Fuel Based on Simulations
Get PDFOne of the alternative and renewable energies is green diesel. Despite the fact that both use the same raw material, vegetable oil, the processes for producing green diesel and biodiesel are somewhat different. Green diesel is generated via the hydrotreating process, which involves injecting hydrogen gas into an oil to remove oxygen. The combustion process in the engine is influenced by the nature of the fuel. Green diesel fuel has a higher yield of material than biodiesel fuel. High pressure caused by combustion in the engine combustion chamber affects the vibrations and noises of diesel engines. By varying engine speed and load, this study compares noise and vibration produced by green diesel fuel to biodiesel B30 using a simulation process. The results showed that green diesel fuel produces more noise and vibration than biodiesel B30 fuel and that this is directly proportional to the pressure and power produced in the combustion chamber by the green diesel fuel combustion process. As the pressure in the combustion chamber rises, the explosion becomes more powerful, resulting in increased diesel engine noise and vibration
KPI Selection Using The AHP Method on SOE X
Get PDFPT X (Persero), a state-owned enterprise under the Ministry of Indonesia SOEs (KBUMN), is required to set up the Key Performance Indicators (KPI) Regulations based on the Assessment Criteria for Performance Excellence (KPKU). The re-weighting of KPIs using the Analytical Hierarchy Process (AHP) method is conducted by selecting performance indicators based on five perspectives. Based on the study results, selected performance measures for financial and market perspectives are cash position, cash-to-cash time cycle, income, and financial operations efficiency. Selected performance measures for customer focus perspective are customer complaints, complaint management, effective complaint resolution, and warranty claims; customer satisfaction and dissatisfaction; and retention, acquisition, and loss of customers and customer accounts. Selected performance measures for product and process effectiveness perspective are product performance, work system performance, improved performance of administrative functions and other supporting functions; and indicators of internal responsiveness. Selected performance measures for the perspective of workforce focus are turnover and effectiveness of training, retraining, or cross-functional training. Selected performance measures for leadership, governance, and community responsibility perspectives are the company's contribution to social welfare, achievements worthy of note in this field; and environmental, legal, and regulatory compliance
Improvement Design for The Effectiveness of Tracer Studies Process in Bandung’s Private University
Get PDFA concrete step to obtain information is to have a good management information system. For universities, one of the most important information is about alumni or graduate’s feedback. However, the actual management information system in several Bandung’s private university cannot provide the information desired by the department and the tracer studies response rate is far from good. Which means the tracer study process needs to be re-engineered. Thus, this research aims to redesign the business processes by analyzing the “As-Is”. This research found that a good tracer study system needs to build a good relationship with the alumni. So that, this research proposes the key success factor for the effectiveness of tracer studies in Bandung’s private universities. Since the response rate is one of the key indicators of tracer studies, supposed that in order to increasing the response rate. The universities should create good relationships with the alumni since they were in sophomore year with their guardian lecturer and thesis’ promotor. Thus, this reengineered process should be useful in order to increase the tracer studies process productivity that measured by response rate to supports national data collection and comparisons for better education curriculum evaluations
Financial Distress Prediction Models in Property Sector Companies Listed in Indonesia Stock Exchange
Get PDFAlong with the unstable national and global economic conditions, investors and consumers defend themselves to invest in the property sector. Companies go public in obtaining capital markets as a means to obtain sources of funds. Investors and creditors will see the financial condition required before the company will increase financial distress (financial distress) or not before investing their capital. Therefore, analysis and prediction of a company's financial problems is very important. This study uses the Financial Distress model by using discriminant analysis. The independent variables used are financial ratios which are divided into 4 categories (1) Liquidity Ratios, (2) Solvency Ratios, (3) Activity Ratios, (4) Profitability Ratios. This research uses quantitative with the Multivariate Discriminant Analysis (MDA) model. The sample data used in this study includes property, real estate, and construction sector companies listed on the Indonesia Stock Exchange in the 2014-2018 period. This study produces a financial distress model Z-score = -3,569 + 6,910DTA -1.107DTE + 7,515ROE + 3,573OPM with a cut-off value of -3,521. When the z-score of the company -3,521, the company is included in the non-financial pressure group
Implementation of Risk-Based Inspection (RBI) in Condensate Separator and Storage Vessel: A Case Study
Get PDFIn the processing of oil and gas, a pressure vessel is an important piece of equipment. It needs a method to prevent the failure of the pressure vessel. The Risk-Based Inspection (RBI) is a systematic approach to the inspection management method for equipment based on the level of risk. RBI is expected to provide sufficiently accurate recommendations to prevent equipment failures. In this research, the objects to be carried out are the 10V2102 condensate separator and the 10V2103 condensate storage vessel. According to RBI analysis, the risk category of the current RBI date is low risk for the condensate separator 10V2102 and condensate storage vessel 10V2103. Meanwhile, the inspection date of Condensate Separator 10V2102 is 2 April 2026 and 11 February 2027 for Condensate Storage Vessel 10V2103 and selected inspection methods are Visual Testing, Ultrasonic Testing (UT), Radiography Test (RT), Eddy Current Test, and Magnetic Particle Inspection