Micro-CT Characterization of Wellbore Cement Degradation in SO42-–Bearing Brine under Geological CO2 Storage Environment

In order to explore the process of acid- and CO2-induced degradation of wellbore cement and the development of pre-existing leakage channels in wellbore cement under sulfate-rich geological CO2 storage conditions, wellbore cement samples were immersed in SO42--bearing brine solution for 7 days, and the samples after reacting with the low and circumneutral pH solutions were scanned by a micro-CT scanner. HCl+Na2SO4 solution was used to simulate the low-pH condition in deep formation waters and the possible existence of high sulfate ion content in deep formation waters. The acidification and carbonation results were compared, and the results given different pH values and different curing conditions were compared as well. The results show that the degradation of cement was related to the pH value of the reaction solution. There was a significant dissolution in the exterior of the cement sample after exposure to the low-pH solution, but the dissolution surrounding a penetrating borehole at the center of the sample (mimicking a leakage pathway within the wellbore cement in geological CO2 storage environment) was limited. Comparison between acidification and carbonation results in this study shows formation of a thick carbonate layer due to cement carbonation, and this layer was not observed in the acidification result. As for different curing conditions of cement samples, no significant difference in cement alteration depth was observed for the acidification case. For the carbonation case, precipitations in the borehole occurred in the cement sample cured at ambient pressure, while the cement sample cured at high pressure did not produce any precipitation in the borehole. This study provides valuable information on how low pH-induced corrosion and HCO3--induced cement carbonation contribute to structure evolution of wellbore cement in SO42--bearing brine under geological CO2 storage environment.

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Influence of Fibers and Curing Conditions on the Pore Morphology in Plain and Fiber-Reinforced High-Performance Concrete through the Use of Computed Tomography Scan Technology

Applied Sciences ◽

10.3390/app10124286 ◽

2020 ◽

Vol 10 (12) ◽

pp. 4286

Author(s):

Dorys C. González ◽

Mohammad Rahman ◽

Jesús Mínguez ◽

Miguel A. Vicente ◽

Riyadh Hindi

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Pore Morphology ◽

Micro Ct ◽

Fiber Reinforced ◽

Ct Scanner ◽

Curing Conditions ◽

Concrete Mixtures ◽

The One ◽

Tomography Scan

This paper analyzes the pore morphology of two different concrete mixtures (plain and fiber-reinforced) under two different curing conditions, through the use of a CT scanner and post-processing software. Twelve cylinders of 45.2 mm in diameter and 50 mm in height were cast. Half of the specimens were kept in a humidity-controlled room, at 20 °C and 60% humidity, and the rest in a curing room, at 20 °C and 100% humidity. All the specimens were scanned at the age of 28 days, using a micro CT scanner. The results reveal that the presence of fibers substantially modifies the pore morphology in the way of increasing the volume of voids and the pore-size, reducing the shape factor of the voids and reorienting the voids toward a direction more aligned to the one showed by the fibers. In general, the curing conditions do no exhibit a great impact on the results.

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Evaluation of Organ Dose and Image Quality Metrics of Pediatric CT Chest-Abdomen-Pelvis (CAP) Examination: An Anthropomorphic Phantom Study

Applied Sciences ◽

10.3390/app11052047 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2047

Author(s):

Nor Azura Muhammad ◽

Zunaide Kayun ◽

Hasyma Abu Hassan ◽

Jeannie Hsiu Ding Wong ◽

Kwan Hoong Ng ◽

...

Keyword(s):

Image Quality ◽

Multidetector Ct ◽

Organ Dose ◽

Quality Metrics ◽

Ct Scanner ◽

Image Quality Metrics ◽

Tube Current ◽

Significant Difference ◽

Noise Ratio ◽

The Impact

The aim of this study is to investigate the impact of CT acquisition parameter setting on organ dose and its influence on image quality metrics in pediatric phantom during CT examination. The study was performed on 64-slice multidetector CT scanner (MDCT) Siemens Definition AS (Siemens Sector Healthcare, Forchheim, Germany) using various CT CAP protocols (P1–P9). Tube potential for P1, P2, and P3 protocols were fixed at 100 kVp while P4, P5, and P6 were fixed at 80 kVp with used of various reference noise values. P7, P8, and P9 were the modification of P1 with changes on slice collimation, pitch factor, and tube current modulation (TCM), respectively. TLD-100 chips were inserted into the phantom slab number 7, 9, 10, 12, 13, and 14 to represent thyroid, lung, liver, stomach, gonads, and skin, respectively. The image quality metrics, signal to noise ratio (SNR) and contrast to noise ratio (CNR) values were obtained from the CT console. As a result, this study indicates a potential reduction in the absorbed dose up to 20% to 50% along with reducing tube voltage, tube current, and increasing the slice collimation. There is no significant difference (p > 0.05) observed between the protocols and image metrics.

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A Study of Wideband Energy Reflectance in Patients with Otosclerosis: Data from a Chinese Population

BioMed Research International ◽

10.1155/2019/2070548 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Suju Wang ◽

Wenyang Hao ◽

Chunxiao Xu ◽

Daofeng Ni ◽

Zhiqiang Gao ◽

...

Keyword(s):

Resonance Frequency ◽

Racial Differences ◽

Chinese Population ◽

Ambient Pressure ◽

Control Group ◽

Age And Gender ◽

Significant Difference ◽

And Gender ◽

And Control ◽

Peak Pressures

Objective(s). The purpose of this study was to explore the effectiveness of wideband acoustic immittance (WAI) in the diagnosis of otosclerosis by comparing the differences in the energy reflectance (ER) of WAI between patients with otosclerosis and age- and gender-matched normal hearing controls in the Chinese population. Methods. Twenty surgically confirmed otosclerotic ears were included in the otosclerotic group. The ER of WAI at ambient and peak pressures, resonance frequency, and 226-Hz tympanogram were collected prior to surgery using a Titan hearing test platform (Interacoustics A/S, Middelfart, Denmark). All diagnoses of otosclerosis in the tested ear were confirmed by surgery after the measurements. Thirteen normal adults (26 ears) who were age- and gender-matched with the otosclerotic patients were included as the control group. Results. At peak pressure, the ERs of otosclerotic patients were higher than those of the control group for frequencies less than 4,000Hz and were lower for frequencies greater than 4,000Hz. In addition, within the analyzed frequencies, the differences observed at 2,520Hz was statistically significant (p<0.05/16=0.003, Bonferroni corrected). At ambient pressure, the differences observed at 1,260 and 6,350Hz were statistically significant (p<0.05/16=0.003, Bonferroni corrected). Although the differences between the otosclerotic and control groups exhibited similar trends to those in studies implemented in Caucasian populations, the norms in the present study in the control group were different from those in the Caucasian populations, suggesting racial differences in WAI test results. Regarding the middle ear resonance frequency, no significant difference was observed between the two groups (P>0.05). Conclusion. WAI can provide valuable information for the diagnosis of otosclerosis in the Chinese population. Norms and diagnostic criteria corresponding to the patient’s racial group are necessary to improve the efficiency of WAI in the diagnosis of otosclerosis.

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Degradation of methylene blue by natural manganese oxides: kinetics and transformation products

Royal Society Open Science ◽

10.1098/rsos.190351 ◽

2019 ◽

Vol 6 (7) ◽

pp. 190351 ◽

Cited By ~ 3

Author(s):

Shuangxi Zhou ◽

Zhiling Du ◽

Xiuwen Li ◽

Yunhai Zhang ◽

Yide He ◽

...

Keyword(s):

Methylene Blue ◽

Manganese Oxides ◽

Ph Value ◽

Low Cost ◽

Reaction System ◽

Transformation Products ◽

Low Ph ◽

Initial Concentration ◽

Environmental Material ◽

High Redox Potential

In this study, natural manganese oxides (MnO x ), an environmental material with high redox potential, were used as a promising low-cost oxidant to degrade the widely used dyestuff methylene blue (MB) in aqueous solution. Although the surface area of MnO x was only 7.17 m 2 g −1 , it performed well in the degradation of MB with a removal percentage of 85.6% at pH 4. It was found that MB was chemically degraded in a low-pH reaction system and the degradation efficiency correlated negatively with the pH value (4–8) and initial concentration of MB (10–50 mg l −1 ), but positively with the dosage of MnO x (1–5 g l −1 ). The degradation of MB fitted well with the second-order kinetics. Mathematical models were also built for the correlation of the kinetic constants with the pH value, the initial concentration of MB and the dosage of MnO x . Furthermore, several transformation products of MB were identified with HPLC-MS, which was linked with the bond energy theory to reveal that the degradation was initiated with demethylation.

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Heterotrophic Bacteria Play an Important Role in Endemism of Cephalostachyum pingbianense (Hsueh & Y.M. Yang ex Yi et al.) D.Z. Li & H.Q. Yang, 2007, a Full-Year Shooting Woody Bamboo

Forests ◽

10.3390/f13010121 ◽

2022 ◽

Vol 13 (1) ◽

pp. 121

Author(s):

Tize Xia ◽

Lushuang Li ◽

Bin Li ◽

Peitong Dou ◽

Hanqi Yang

Keyword(s):

Bacterial Community ◽

Soil Microbes ◽

Heterotrophic Bacteria ◽

Ph Value ◽

Germplasm Conservation ◽

Plant Distribution ◽

Soil Bacterial Diversity ◽

Significant Difference ◽

Woody Bamboos ◽

Soil Bacterial

The previous studies show soil microbes play a key role in the material and nutrient cycles in the forest ecosystem, but little is known about how soil microbes respond to plant distribution, especially in the soil bacterial community in woody bamboo forests. Cephalostachyum pingbianense (Hsueh & Y.M. Yang ex Yi et al.) D.Z. Li & H.Q. Yang, 2007 is known as the only bamboo species producing shoots all year round in natural conditions. Endemic to the Dawei mountain in Yunnan of China, this species is a good case to study how soil bacteria respond to plant endemic distribution. In this work, we assayed the soil chemical properties, enzyme activity, changes in the bacterial community along the distribution range of the C. pingbianense forest. The results showed that soil nutrients at the range edge were nitrogen-rich but phosphorus-deficient, and soil pH value and soil urease activity were significantly lower than that of the central range. No significant difference was detected in soil bacterial diversity, community composition, and function between the central and marginal range of C. pingbianense forest. Notably, the relative abundance of heterotrophy bacteria, such as Variibacter and Acidothermus, in the soil of the C. pingbianense forest was significantly higher than that of the outside range, which may lead to a higher soil organic carbon mineralization rate. These results imply that abundant heterotrophy bacteria were linked to the endemism and full-year shooting in C. pingbianense. Our study is amongst the first cases demonstrating the important role of heterotrophy bacteria in the distribution formation of endemic woody bamboos in special soil habitats, and provides insight into germplasm conservation and forest management in woody bamboos.

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PENGARUH KONSENTRASI STARTER BAKTERI Lactobacillus plantarum TERHADAP BEBERAPA KOMPONEN MUTU TEPUNG PORANG (Amorphophallus oncophyllus)

Pro Food ◽

10.29303/profood.v6i2.136 ◽

2021 ◽

Vol 6 (2) ◽

pp. 673

Author(s):

Ade Irma Juliana ◽

Moegiratul Amaro ◽

Nazaruddin Nazaruddin

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Protein Content ◽

Lactobacillus Plantarum ◽

Analysis Of Variance ◽

Ph Value ◽

Significance Level ◽

Randomized Design ◽

Significant Difference ◽

Polynomial Orthogonal

ABSTRACT This study aims to determine the effect of Lactobacillus plantarum bacterial starter concentration on some quality of the porang flour. This study used experimental design one-factor Completely Randomized Design (CRD) consisted of BAL concentration (KB) of Lactobacillus plantarum with 6 treatments which is 0%, 5%, 10%, 15%, 20% and 25%. Each of treatment were repeated three times to obtain 18 unit samples. Data from observations were analyzed using analysis of variance (Analysis of Variance) at 5% significance level using Co-stat software. If there are significant differences, a further Polynomial Orthogonal and Honestly Significant Difference (BNJ) test is performed at a level of 5%. The parameters observed included pH value, protein content, water content, yield, total lactic acid bacteria, organoleptic parameters of color and aroma (hedonic and scoring). The results showed that the concentration of Lactobacillus plantarum bacterial 20% was the best treatment in producing porang flour, pH value 5.72, protein content 6.49%, yield 9.33%, total lactic acid bacteria 6.66 log CFU / g and color rather brown and slightly acidic aroma and somewhat preferred by panelists. Keywords: Porang flour, starter concentration, Lactobacillus plantarum ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi starter bakteri Lactobacillus plantarum terhadap beberapa komponen mutu tepung porang. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan satu faktor yakni konsentrasi BAL (KB) jenis Lactobacillus plantarum dengan 6 perlakuan yaitu 0%, 5%, 10%, 15%, 20% dan 25%. Masing-masing perlakuan diulang sebanyak 3 kali sehingga diperoleh 18 unit percobaan. Data hasil pengamatan dianalisis menggunakan analisis keragaman (Analysis of Variance) pada taraf nyata 5% menggunakan software Co-stat. Apabila terdaapat beda nyata, dilakukan uji lanjut Polynomial Orthogonal dan Beda Nyata Jujur (BNJ) pada taraf 5%. Adapun parameter yang diamati meliputi nilai pH, kadar protein, kadar air, rendemen, total bakteri asam laktat, parameter organoleptik warna dan aroma (hedonik dan scoring). Hasil penelitian menunjukkan bahwa konsentrasi strater bakteri Lactobacillus plantarum 20% merupakan perlakuan terbaik dalam menghasilkan tepung porang nilai pH 5,72, kadar protein 6,49%, rendemen 9,33%, total bakteri asam laktat 6,66 log CFU/g serta warna agak coklat dan aroma agak asam serta agak disukai panelis. Kata Kunci: Tepung porang, konsentrasi starter, Lactobacillus plantarum

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Comparison of the Hounsfield Unit Values Obtained From Cone-Beam Computed Tomography (CBCT) and Multidetector Computed Tomography (MDCT) Images for Different Bone Densities

Journal of Contemporary Medical Sciences ◽

10.22317/jcms.v7i2.943 ◽

2021 ◽

Vol 7 (2) ◽

Author(s):

Atefeh Khavid ◽

Mojgan Sametzadeh ◽

Mostafa Godiny ◽

Mohammad Mehdi Moarrefpour

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Pearson Correlation ◽

Hounsfield Unit ◽

Cone Beam ◽

Ct Scanner ◽

Significance Level ◽

Dental Practitioners ◽

Significant Difference ◽

The Mean

Background and objective: In recent years, cone-beam computed tomography (CBCT) has become a key diagnostic tool in dentistry. CBCT can provide 3D images of the maxillofacial area to help dental practitioners in diagnosis and treatment, especially implant placement and treatment of pathogenic lesions. This study aimed to compare the Hounsfield Unit (HU) values obtained from CBCT images for bones of different densities with the corresponding HU values from MDCT images. Materials and methods: cube-shaped bone blocks of identical size were cut from the middle section of the cow ribs and femur area such that they had a layer of cortical bone in their buccal, lingual, and top surfaces and trabecular bone in the middle. MDCT scans were performed using a Somatom Sensation Ct Scanner. After determining HU from the results of these scans, nine suitable specimens from different ranges of HU were chosen for comparison. HU of the CBCT images was computed by the dedicated software of the CBCT machine. Finally, HU values obtained from MDCT and CBCT were compared. Data analysis was performed using SPSS version 25 at the 0.05 significance level. Results: The results showed a statistically significant difference between the mean HU from MDCT images and the mean HU from CBCT images (P<0.05). For similar specimens, CBCT produced higher mean HU values than MDCT. The Pearson correlation test detected a significant direct relationship between the HU values of specimens in MDCT and CBCT (P<0.05). Conclusion: For the tools and software used in this study, there was no significant difference between the HU values obtained from MDCT and CBCT, but the mean HU obtained from CBCT was higher than that from MDCT.

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Bacteriocin Activity of Lactic Acid Bacteria Isolated from Rumen Fluid of Thin Tail Sheep

Buletin Peternakan ◽

10.21059/buletinpeternak.v43i3.36837 ◽

2019 ◽

Vol 43 (3) ◽

Author(s):

Okti Widayati ◽

Zaenal Bachruddin ◽

Chusnul Hanim ◽

Lies Mira Yusiati ◽

Nafiatul Umami

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Ph Value ◽

Heating Temperature ◽

Rumen Fluid ◽

Bacteriocin Activity ◽

Significant Difference ◽

Sheep Rumen ◽

The Stability ◽

Range Test

The objective of this study was to determine the activity and the stability of bacteriocin from lactic acid bacteria (BAL) isolated from rumen fluid of thin-tail sheep under the temperature (80, 100, and 121°C), pH (3, 7, and 10), and the length of storage (for 2 weeks under the temperature -8, 11, and 29°C). Lactic acid bacteria obtained by isolation, selection, and identification of thin-tailed sheep rumen fluid were used for bacteriocin production. The crude bacteriocin was partially purified using 70% ammonium sulfate, then was dialysis for 12 hours. The obtained bacteriocin then tested its inhibitory activity against E.coli (representing Gram-negative) and S. aureus (representing Gram-positive) under temperature (80, 100, and 121°C), pH (3, 7, and 10), and the length of storage (for 2 weeks under the temperature -8, 11, and 29°C). The data of bacteriocin activity based on pH, temperature, and the length of storage were analyzed with factorial, then when there was a significant difference of variable because treatment was continued with Duncan's Multiple Range Test (DMRT) test. The results showed that the bacteriocin activity of the three types of BAL against S.aureus is greater than E.coli. The highest activity was shown in pH 3, while the lowest activity was shown at pH 10 (P<0.01). The highest activity was shown at a heating temperature of 100°C, while the lowest activity was shown at a heating temperature of 80°C (P<0.01). The activity of bacteriocin produced by BAL 0 A, BAL 1 A, and BAL 4 C tended to be stable to the heating temperature of 80, 100, and 121°C but decreased with increasing pH value (pH 3, 7, and 10). The best of bacteriocin activity was found at pH 3 (acid), heating at 100°C, and stored at -8°C for 14 days.

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KONSENTRASI KARAGENAN TERHADAP FISITOKIMIA DAN ORGANOLEPTIK JELYDRINK KRAI

Jurnal Litbang Provinsi Jawa Tengah ◽

10.36762/litbangjateng.v16i2.761 ◽

2019 ◽

Vol 16 (2) ◽

pp. 153-164

Author(s):

Eny Hari Widowati ◽

Dewi Larasati

Keyword(s):

Water Content ◽

Research Methods ◽

Ph Value ◽

Dry Season ◽

Added Value ◽

Assessment Criteria ◽

Cattle Feed ◽

Significant Difference

Krai is a group of vegetables that are widely planted by the community in Kasreman Village, Rembang Regency, Krai is planted every dry season with abundant production. the production of abundant krai and sold in fresh form causes low prices of krai even used as cattle feed, this is because krai does not have added value. Krai has the potential to be processed into various food preparations. one of them is processed jelly drink because of the typical water content in vegetables and aroma. Processing of jelly drinks with krai has not been done so that the use of carrageenan needs to be known for its concentration to be accepted by consumers. Research methods: experiment with simple RAK with carrageenan concentration: K1:2%; K2:4%; K3:6%; K4:8%. For organoleptics use student panelists who are accustomed to organoleptic tests with assessment criteria ˃2-3: Dislike; ˃3-4%: Enough Likes; ˃4-5%: Like; ˃5-6%: Very Like. Results:i) Carrageenan concentration against pH: There are significant differences between treatments. The highest pH was found in treatment K4 (4.26) Increase in carrageenan concentration followed by an increase in pH value;ii) Carrageenan Concentration Against Viscosity there is a very significant difference between treatments The less carrageenan concentration, the lower the viscosity or runny; iii) Carrageenan Concentration Against Sineresis: the carrageenan concentration given had a significant effect on the value of sineresis. The syneresis analysis of roasted jelly drink drinks ranged from 4.51 - 13.47 mg / minute The highest synergy was found in treatment K1. iv) The preferred concentration of texture, taste, aroma is concentration at 0.6%.

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