Widely used charcoal analysis method in paleo studies involving NaOCl results in loss of charcoal formed below 400°C

The Holocene ◽  
2021 ◽  
pp. 095968362110417
Author(s):  
Mark Constantine ◽  
Scott Mooney
Keyword(s):  
Image Analysis ◽  
High Temperature ◽  
Fire History ◽  
Total Surface Area ◽  
Dilute Solution ◽  
Charcoal Analysis ◽  
Analysis Method ◽  
Low Intensity ◽  
Before And After ◽  
Non Destructive

This study investigated the effects a dilute solution of bleach (4% sodium hypochlorite), has on charcoal. We were particularly interested in considering if charcoal formed under different conditions of pyrolysis was differentially affected by this treatment, which is commonly used for the quantification of charcoal in sediments. We first produced a series of charcoal samples, under laboratory conditions (at temperatures between 250°C and 800°C and under oxygen limited conditions) and then measured total surface area of charcoal before and after treatment in a solution of 4% bleach. We found that charcoal formed ⩽400°C showed nearly complete bleaching after 24 h, while high temperature charcoal (>400°C) was much more resistant. These results indicate this treatment bleaches charcoal formed at lower temperatures: this means particles charred at low temperature may not be quantified in common optical counting or image analysis methods. This could have serious ramifications for sediment-based paleofire research as low intensity fire may be lost from a record, and the resulting fire history biased towards high intensity (high temperature) fires. Our findings suggest the need for a new, non-destructive method for extracting charcoal from sediment.

scholarly journals The ultrasonic and image analysis method for non-destructive quantification of the thermal shock damage in refractory specimens

2009 ◽  
Vol 30 (8) ◽  
pp. 3338-3343 ◽  
Author(s):  
M. Posarac ◽  
M. Dimitrijevic ◽  
T. Volkov-Husovic ◽  
J. Majstorovic ◽  
B. Matovic
Keyword(s):  
Image Analysis ◽  
Thermal Shock ◽  
Analysis Method ◽  
Image Analysis Method ◽  
Non Destructive

scholarly journals An investigation of using grey scale image analysis for predicting the amount of deposited electrospun nanofibres

2019 ◽  
Vol 13 (1) ◽  
pp. 4679-4692
Author(s):  
A. H. Nurfaizey ◽  
F. C. Long ◽  
M. A. M. Daud ◽  
N. Muhammad ◽  
M. R. Mansor ◽  
...  
Keyword(s):  
Image Analysis ◽  
Deposition Time ◽  
Control Method ◽  
Analysis Method ◽  
Image Analysis Method ◽  
Grey Scale ◽  
Significant Area ◽  
Electrospun Nanofibres ◽  
Weighing Method ◽  
Non Destructive

When electrospinning, the amount of electrospun fibres deposited is difficult to determine due to the extremely small size and light weight of the fibres.  Several methods have been used to predict the amount of deposited fibres including weighing, imaging and direct measurement. Yet, these methods have drawbacks that make them unsuitable for commercial scale process control. In this study, an image analysis method is used to predict the amount of deposited fibres over a significant area. When images of electrospun fibres are converted into grey scale images, it is suggested that the amount of fibres deposited can be predicted by measuring the grey scale intensity. Weighing method was used to validate the image analysis results. Weighing method was found wanting when the deposition time was short (p>0.05) due to the insignificant fibre masses compared to the variation of substrates. The results suggest that image analysis method could be used to predict the amount of deposited electrospun nanofibres. Test on different polymers and substrates showed that the method was still capable to distinguish the samples. The developed method has the potential to be applied as an in-line non-destructive quality control method for electrospun fibre manufacture.

scholarly journals Image analysis on disintegrated concrete at the post-heating stage

2020 ◽  
Vol 10 (2) ◽  
pp. 219-229
Author(s):  
A. H. Akca ◽  
N. Özyurt
Keyword(s):  
Compressive Strength ◽  
Image Analysis ◽  
High Temperature ◽  
Crack Growth ◽  
High Temperature Exposure ◽  
Single Lens ◽  
Temperature Exposure ◽  
Extent Of Damage ◽  
Damage In Concrete ◽  
Non Destructive

The relation between crack growth and reduction in the compressive strength after high temperature exposure and after air re-curing was investigated in this study. Concrete specimens were heated to 1000 ºC and they were subjected to air re-curing for 28 days. During re-curing period, their heated surfaces were monitored by using a digital single-lens reflex camera and the images were analyzed by using image analysis software. After cooling, the maximum reduction in the compressive strength of concrete was 49.5% and that of air re-cured concrete was 66.8%. Image analyses showed high correlations between crack growth and reduction in the compressive strength. This non-destructive method has the potential to represent the extent of damage in concrete after high temperature exposure.

ANALISIS PENGARUH PEMBANGUNAN JALAN LAYANG JANTI TERHADAP PERKEMBANGAN TATA RUANG KAWASAN JANTI STUDI KASUS : KAWASAN JANTI, DESA CATURTUNGGAL, KABUPATEN SLEMAN, D. I. YOGYAKARTA

2017 ◽  
Vol 11 (3) ◽  
pp. 255
Author(s):  
Jeky El Boru
Keyword(s):  
Road Network ◽  
Open Space ◽  
Qualitative Description ◽  
Analysis Method ◽  
Open Spaces ◽  
The Road ◽  
Before And After ◽  
Linkage Method ◽  
The Impact ◽  
Parking Place

Abstract: This research aims to analyze the impact of Janti Flyover Construction toward the growth of layout at Janti Urban Area, including structured space, open space, and linkage. Method used for data collecting are observation, air photograph monitoring, and interview, whereas the analysis method is qualitative description, which is the superimposed method of two layers, that are the layout condition before and after flyover construction. The result shows that the impact of Janti Flyover construction can be seen on building mass (solid), the increasing number of open spaces, including the road network, parking place, and park, whereas the relation between spaces, visually and structurally, can be seen on the growth of buildings which have new shapes and styles, therefore the performance of the overall building does not have a proportional shape. Considering Janti Street at the collective relation, its role is getting stronger as the main frame road network.Keywords: Flyover construction, layout changing, Janti AreaAbstrak: Penelitian ini bertujuan untuk menganalisis pengaruh pembangunan Jalan Layang Janti terhadap perkembangan tata ruang Kawasan Janti, meliputi ruang terbangun, ruang terbuka, serta hubungan antar ruang (“linkage”). Metode pengumpulan data dilakukan melalui observasi, pengamatan foto udara, dan wawancara; sedangkan metode analisis melalui deskripsi secara kualitatif yang berupa “superimposed method” dari dua lapisan kondisi lahan, yakni kondisi tata ruang sebelum dan sesudah pembangunan jalan layang. Hasil penelitian menunjukkan bahwa pengaruh pembangunan Jalan Layang Janti terdapat pada massa bangunan (“solid”), pertambahan ruang terbuka yang berupa jaringan jalan, parkir, dan taman; sedangkan pada hubungan antar ruang ̶ secara visual dan struktural ̶ yakni tumbuhnya bangunan dengan bentuk dan gaya baru, sehingga bentuk tampilan bangunan secara keseluruhan tidak proporsional. Pada hubungan kolektif, Jalan Janti semakin kuat perannya sebagai kerangka utama jaringan jalan.Kata kunci : Pembangunan jalan layang, tata ruang, Kawasan Janti

Print Media and the Political Reform in Ethiopia

2019 ◽  
Vol 14 ◽  
pp. 3356-3371
Author(s):  
Negesse Gessese
Keyword(s):  
Social Changes ◽  
Analysis Method ◽  
Sources Of Information ◽  
Attribution Of Responsibility ◽  
Societal Issues ◽  
Content Selection ◽  
Period 2 ◽  
Content Analysis Method ◽  
Before And After ◽  
Issue Frames

This research examines the agenda and frames used by the Reporter newspaper editorial coverage of issues and actors before and after the reform in Ethiopia. The study applies a quantitative content analysis method and examined 99 (Period 1 = 57 and Period 2 = 42) editorials in all periods. The source of data and the period of data collection were purposely selected. The results indicated that societal issues, government, and party issues were frequent in both periods. The professional journalist was the only Author in both periods. More government criticism and more reforms were mentioned before the reform. Compared with editorials published before and after the reform, noticeable changes were observed in government critique, attribution of responsibility frames, human interest frames and economic issue frames. However, content selection, sources of information, mentioned reforms, conflict relationship frames, and ideological frames didn’t have relationship with the date of publication. Finally, the Reporter editorials coverage did change significantly in many respects, although it is difficult to determine the causes of the changes—economic factors, reduced political control, social changes or globalization forces.

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