scholarly journals PENGUKURAN KETULENAN EMAS MENGGUNAKAN KAEDAH UJIAN TANPA MUSNAH: SUATU ULASAN PERBANDINGAN

2021 ◽  
Vol 9 (2) ◽  
pp. 91-106
Author(s):  
FAZRUL MOHD NOR ◽  
ABD RAHMAN TAMURI ◽  
ABD KHAMIM ISMAIL ◽  
MOHD ERFY ISMAIL ◽  
MOHD HASRIL AMIRUDDIN
Keyword(s):  
Test Method ◽  
X Ray ◽  
Destructive Test ◽  
The Difference ◽  
Gold Industry ◽  
Non Destructive ◽  
And Tungsten

AbstrakPenentuan ketulenan jongkong emas dengan kaedah ujian tanpa musnah adalah perkara yang paling mencabar dalam industri emas terutama jika jongkong emas dipalsukan dengan cara meletakkan tungsten di dalamnya. Instrumen yang sedia ada mempunyai keterbatasan untuk menentukan ketulenan jongkong emas dan sukar untuk mengesan tungsten di dalamnya kerana tungsten mempunyai ketumpatan yang hampir sama dengan emas. Kajian ini mengemukakan keterbatasan instrumen kaedah ujian tanpa musnah seperti densimeter, alat timbangan, sinar-x pendarfluor dan ultrasonik. Dalam kajian ini menemui kesukaran untuk mengenal pasti emas palsu menggunakan instrumen kaedah ujian tanpa musnah seperti ultrasonik dan x-ray fluorescence (XRF) kerana instrumen ini mempunyai batasan. Setakat ini tiada lagi kajian yang berkaitan pemalsuan jongkong emas kerana harganya yang mahal untuk dijadikan sebagai sampel kajian. Masalah jongkong emas palsu dapat diselesaikan jika ketepatan instrumen yang digunakan untuk mengukur ketumpatan dapat ditingkatkan lagi sehingga 0.01 g/ml. Ini kerana perbezaan antara ketumpatan emas dan tungsten adalah 0.05 g/ml. Pemalsuan emas dengan mencampurkan tungsten akan dapat dikesan jika ada instrumen yang mempunyai ketepatan sekurang-kurangnya 0.01 g/ml. Manakala instrumen lain seperti XRF digunakan untuk mengesahkan ketulenan emas di bahagian permukaan sahaja. Oleh itu, bagi pengujian yang lebih menyeluruh masalah jongkong emas palsu ini perlu diselesaikan dengan menggabungkan kedua-dua kaedah ini.   Abstract Determination of the gold bar purity by non-destructive method remains one of the most challenging in gold industry especially when the tungsten is inside the gold bar. The existing instruments have limitations in their accuracy to determine the purity of gold when tungsten also inside the gold bar since both tungsten and gold have almost similar densities. This study presents the limitations of the non-destructive test method instruments such as densimeter, weighing balance, x-ray fluorescence (XRF) and ultrasonic in determining the purity of gold. In this study found the difficulty in identifying counterfeit gold using non-destructive test method instruments such as ultrasonic and XRF due to some limitations. So far, there are no studies related to the counterfeiting of gold bars due to its expensive price to be used as a study sample. The problem of counterfeit gold bars can be solved if the accuracy of the instrument used to measure the density can be further increased up to 0.01 g/ml. This is because the difference between the density of gold and tungsten is 0.05 g/ml. Gold counterfeiting by mixing tungsten will be detectable if there is an instrument that has an accuracy of at least 0.01 g/ml. While other instruments such as XRF will be used to verify the purity of gold on the surface only. Therefore, for more thorough testing the problem of fake gold ingots needs to be solved by combining these two methods.

Determination of Effective Cable Stayed Bridge Link Pin Non-Destructive Test Method

2001 ◽  
Vol 84 (10) ◽  
pp. 33-40
Author(s):  
Woo-Jin Kim ◽  
Ju-Yeob Kim ◽  
Chang-Soo Park ◽  
Theodor Krauthammer ◽  
Jung-Ho Won ◽  
...  
Keyword(s):  
Test Method ◽  
Destructive Test ◽  
Cable Stayed Bridge ◽  
Non Destructive

In Situ Determination of the Elastic Modulus of Concrete by Means of Ultrasonic Pulse Method

2018 ◽  
Vol 272 ◽  
pp. 70-75
Author(s):  
Petr Cikrle ◽  
Dalibor Kocáb ◽  
Barbara Kucharczyková ◽  
Ondřej Anton
Keyword(s):  
Elastic Modulus ◽  
Pulse Method ◽  
Ultrasonic Pulse ◽  
In Situ Measurements ◽  
Test Method ◽  
Destructive Test ◽  
Non Destructive ◽  
Thick Layers

The paper deals with the in-situ determination of the modulus of elasticity on the bridge elements using ultrasonic pulse method. This non-destructive test method was chosen for the measurement because of its undisputed advantages that allow the measurement of relatively thick layers of material. For the purpose of the elastic modulus verification the direct measurement was used, in which a pair of transducers (transmitter and receiver) were placed directly opposite to each other. The results of performed in-situ measurements as well as the results of verification tests performed in the laboratory are presented in the paper. The article also discusses the issue of evaluation and interpretation of the results obtained by in-situ measurements using non-destructive test method.

Stoichiometric Determination of Graphite Intercalation Compounds Using Rutherford Backscatiering Spectrometry

1983 ◽  
Vol 27 ◽  
Author(s):  
L. Salamanca-Riba ◽  
B.S. Elman ◽  
M.S. Dresselhaus ◽  
T. Venkatesan
Keyword(s):  
Experimental Error ◽  
Rutherford Backscattering Spectrometry ◽  
Rutherford Backscattering ◽  
Intercalation Compounds ◽  
Graphite Intercalation Compounds ◽  
X Ray ◽  
Donor And Acceptor ◽  
Graphite Intercalation ◽  
Non Destructive

ABSTRACTRutherford backscattering spectrometry (RBS) is used to characterize the stoichiometry of graphite intercalation compounds (GIC). Specific application is made to several stages of different donor and acceptor compounds and to commensurate and incommensurate intercalants. A deviation from the theoretical stoichiometry is measured for most of the compounds using this non-destructive method. Within experimental error, the RBS results agree with those obtained from analysis of the (00ℓ) x-ray diffractograms and weight uptake measurements on the same samples.

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