1,561 research outputs found
Theoretical and Experimental Investigations of the Corrosion Inhibition Action of Piliostigma Thonningii Extract on Mild Steel in Acidic Medium
Communication in Physical Science 2018, 3(1):27-42
Theoretical and Experimental Investigations of the Corrosion Inhibition Action of Piliostigma Thonningii Extract on Mild Steel in Acidic Medium
Received 05 July 2018/Accepted September 2018
The search for green corrosion inhibitor for mild steel in solution of HCl was implemented in this work by using electrochemical polarization, gravimetric and thermometric techniques to investigate the corrosion inhibition efficiency of ethanol extract of Piliostigma thonningiil leaf. Results obtained from weight loss and thermometric measurements indicated that the inhibition efficiency of ethanol extract of Piliostigma thonningii leaf ranged from 65.12 to 79.55 % and from 73.61 to 88.16 % respectively. The ranges for inhibition efficiencies from, linear and potentiodynamic polarization measurements were 66.40 to 89.97 % and 51.29 to 85.53 % respectively Active components of the extracts that synergistically cooperated to enhance their adsorption on mild steel surface (and hence corrosion inhibition) were identified through GCMS analysis and they included 1,1,7-trimethyl-4-methylenedecahydro-1H-cyclopropa[e]azulene; hydroquinone; 3-tridecene; 3,5-bis(1,1-dimethylethyl)-phenol; Pentadecanoic acid; 1- ethenyl-1-methyl-2,4-bis(1-methylethenyl)-cyclohexane and 9-oxa-bicyclo[3,3,1]nona-3,6- dien-2-one. Results from quantum chemical calculations revealed that these compounds (apart from meeting the basic requirements for corrosion inhibition) are characterized by frontier molecular energy values that are unique for well-known corrosion inhibitors
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Wire Position Monitoring with FPGA based Electronics
This fall the first Tesla-style cryomodule cooldown test is being performed at Fermilab. Instrumentation department is preparing the electronics to handle the data from a set of wire position monitors (WPMs). For simulation purposes a prototype pipe with a WMP has been developed and built. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The wire is stretched along the pipe with a tensioning load of 9.07 kg. The WPM consists of four 50 {Omega} striplines spaced 90{sup o} apart. FPGA based digitizer scans the WPM and transmits the data to a PC via VME interface. The data acquisition is based on the PC running LabView. In order to increase the accuracy and convenience of the measurements some modifications were required. The first is implementation of an average and decimation filter algorithm in the integrator operation in the FPGA. The second is the development of alternative tool for WPM measurements in the PC. The paper describes how these modifications were performed and test results of a new design. The last cryomodule generation has a single chain of seven WPMs (placed in critical positions: at each end, at the three posts and between the posts) to monitor a cold mass displacement during cooldown. The system was developed in Italy in collaboration with DESY. Similar developments have taken place at Fermilab in the frame of cryomodules construction for SCRF research. This fall preliminary cryomodule cooldown test is being performed. In order to prepare an appropriate electronic system for the test a prototype pipe with a WMP has been developed and built, figure 1. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The 0.5 mm diameter Cu wire is stretched along the pipe with a tensioning load of 9.07 kg and has a length of 1.1 m. The WPM consists of four 50 {Omega} striplines spaced 90{sup o} apart. An FPGA based digitizer collects the WPM data and transmits it to the VME controller. The VME front-end processes the raw data to calculate positions and perform FFT. It is also provides the raw data to LabView running on a PC upon request. In order to increase the accuracy and convenience of the measurements some modifications were required. The first is connected with realization of average and decimation filter algorithm in the integrator operation in the FPGA. The second is connected with development of alternative tool for WPM measurements in the PC. We will discuss how these modifications were performed and test results of a new design
Pengembangan Aplikasi Bimbingan Tugas Akhir Mahasiswa Berbasis Website pada Program Studi Pendidikan Guru Sekolah Dasar Fkip Universitas Riau
This research is research of application development of final project of student based on website at Prodi PGSD FKIPUniversitas Riau by using waterfall model. The formulation of the problem in this research are: (1) how the design ofdeveloping the final project application of student based on the website of Prodi PGSD FKIP Universitas Riau? and (2)whether the program designed to assist the final project guidance on Prodi PGSD FKIP University of Riau ?. The purpose ofthis research is (1) to design a system that can assist the process of guidance of final assignment of students to Prodi PGSDFKIP Universitas Riau and (2) to know the response about the use of application of final student task based on the website ofProdi PGSD FKIP Universitas Riau. This research is a development research with waterfall model. Development stage isdone in four stages, namely: (1) stage study of literature; (2) needs analysis phase; (3) application design; and (4)application testing phase and conclusion. The result of the research stated that the application of the final assignment of thestudents based on the website of PGSD Study Program of FKIP Universitas Riau is valid with four references, namely: (1)correctness aspect (truth); (2) reliability (reliability) aspect; (3) integrity; and (4) USAbility (USAge). Based on the results ofeffectiveness test on the students obtained data that the application of the final project-based student guidance websiteincluded in the category of very effective average percentage is 84.89% with very effective category. It is marked by theacquisition: 1) the correctness (truth) of 84.93% with very effective category; 2) reliability (reliability) of 86.37% with veryeffective category; 3) integrity (integration) equal to 86,08% with very effective category; and 4) USAbility (USAge) of 82.17%with very effective category. The average percentage is 84.89% with very effective category. So it can be concluded that theapplication development of final student task based on the website Prodi PGSD FKIP University of Riau has been declaredeffective and has been widely used
Kemampuan Mahasiswa Pgsd Fkip Universitas Riau dalam Menulis Surat Resmi
The research is descriptive quantitative research conducted to look at the ability of students in the class of 2014 to write a formal letter, a technique in data collection in the form of observation results by student writing an official letter PGSD FKIP Riau University class of 2014 instrument validity of his research has been validated through expert judgment. The sample in this study as masy as 46 students of primary school teaching force in 2014 the Faculty of Education, University of Riau. The ability of students PGSD FKIP Riau University after analyzed using categories, from 12 aspects outlined in the instrument observation sheets, getting the results that the completeness aspect predicate section of the letter simply by percentage (65, 76%), while the writing aspect letterhead good predicate with percentage (79,89%), while the aspect of writing an official letter dated sufficient predicate with percentage (54, 35%), while the aspect of writing about the letter predicate less by percentage (35, 87%), while the writing aspect of the destination address with sufficient predicate persentage (59, 78%), while the aspect of writing greeting predicate simply by percentage (54,35%), while the contents of the letter writing aspect predicate simply by percentage (63,04%), while the writing aspect regards predicate cover less by percentage (42, 93%), while in writing the name of the sender predicate very well with percentage (98, 91%), while the use of indonesioan predicate either by percentage (71, 74%), while in the aspect of the preparation of sufficient premises sentence predicate percentage (58,15%) and on aspects of the form or neatness letter predicate simply by percentage (58, 15%). From the results, the average overall percentage of 61, 91% is obtained with neough categories, this suggests that the ability of students PGSD class of 2014 FKIP University of Riau still low in writing a formal letter
Analisis Teks Puisi dalam Buku Pegangan Guru Buku Penilaian Autentik Penerbit Erlangga di Kelas V Sekolah Dasar
This study, entitled Analysis of the poem text in teacher handbooks, book publishers authentic assessment v erlangga in primary school classroom. In the 2013 curriculum learning poetry still be learned in elementary school therefore collection of poems in which there are some poems which will be analyzed in order to understand the meaning of the poem. The method used in this research is descriptive method through literature. Descriptive research method can be interpreted as a troubleshooting procedure investigated by describing or depicting the state of the subject or object at the present time based on facts that appear or as it is. Poems contained in the book authentic assessment fifth grade elementary school publisher grants the use of figurative language, there are 6 kinds of figurative language that is personification, sinekdot, allegorical, parable epics, metonymy, metaphor and hipalase while in some poetry still use the meaning of denotation as in poetry entitled Lingkunganku and Negeriku
Penerapan Model Pembelajaran Kooperatif Tife Dua Tinggal ( Two Stay Two Stray ) Untuk Meningkatkan Hasil Belajar IPS Siswa Kelas IV SD Negeri 40 Pekanbaru
Backgroun in this research were teachers still use the lecture method and assignments are give students soas to make the students guickly bored with the result that less than the maximum.It is visible symptoms on student attitudes, play in learning and less responds to a question or an explanation of from the teacher. Fot it needs to be done research of learning model two stay two stray. In this leaning students learning with two stay two stray in place group form of this research is classroom action research (PTK). This research aims to improve learning outcomes IPS of cassl IV elementary school 40 pekanbaru. The data obtained is guantitative data. The formulation of problem is”is the implementation cooperative learning model two stay two stray can improve learning outcomes IPS of class IV elementary school 40 Pekanbaru?. Quantitative data such as test results of student outcomes through repetition cycle. Increase in outcomes IPS students of the average value of basic score is 63,5 increased to 79,82 at the end of repetition cycle I with a large increased is 25,70%. The next value of average basic score 63,5 increased to 83,93 at the end of repetition cycle II with a large increased is 32,17%. And the next value of the average basic score 63,5 increased to 89,64 at the and repetition cycle III with a large increased is 41,16%
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