Natthaphong Konkhunthot, Patcharanut Buranapima, Patipan Boonnitee, M. Masae, P. Kongsong
{"title":"Enhanced Surface Hardness of Commercially Pure Titanium by Pack Carburization with Rubberwood Charcoal and Rubberwood Ash","authors":"Natthaphong Konkhunthot, Patcharanut Buranapima, Patipan Boonnitee, M. Masae, P. Kongsong","doi":"10.48048/wjst.2021.20632","DOIUrl":"https://doi.org/10.48048/wjst.2021.20632","url":null,"abstract":"In the present work, pack carburization with rubberwood charcoal and rubberwood ash at 925 °C for 6, 12, and 24 h was carried out to improve the surface hardness of commercially pure titanium (CP-Ti). X-ray diffraction and energy dispersive spectrometer analyses revealed the formation of titanium carbide (TiC) and the existence of oxygen diffusion in the carburized surface. The surface hardness of most optimized conditions has remarkably increased by 481 % as compared to untreated CP-Ti (from 175 HV to 1016 HV) due to the TiC surface layer, while the hardened oxygen diffusion layer of about 300 μm in-depth, as clearly seen in the microhardness profiles is useful for increased load-bearing capacity. Consequently, pack carburization with rubberwood charcoal and rubberwood ash is a promising surface modification technique, which can significantly enhance the surface hardness and increase the load-bearing capacity of CP-Ti for biomedical and tribological applications. \u0000HIGHLIGHTS \u0000 \u0000Rubberwood charcoal and ash are a new carbon source to fabricate the TiC layer on CP-Ti. \u0000Formation of the TiC layer remarkably enhances the surface hardness of CP-Ti by 481 %. \u0000The hardened oxygen diffusion layer is beneficial to load-bearing and anti-wear capacity. \u0000 \u0000GRAPHICAL ABSTRACT","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"152 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120871481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Resource Management for Minimizing Energy and Cost of Geo-Distributed Data Centers","authors":"Moh Moh Than","doi":"10.48048/wjst.2021.9619","DOIUrl":"https://doi.org/10.48048/wjst.2021.9619","url":null,"abstract":"Geo-distributed data centers (GDCs) house computing resources and provide cloud services across the world. As cloud computing flourishes, energy consumption and electricity cost for powering servers of GDCs also soar high. Energy consumption and cost minimization for GDCs has become the main challenge for the cloud service providers. This paper proposes a resource management framework that accomplishes resource demand prediction, ensuring service level objective (SLO), electricity price prediction, and energy-efficient and cost-effective resource allocation through GDCs. This paper also proposes an energy-efficient and cost-effective resource allocation (EECERA) algorithm which deploys energy efficiency factors and incorporates the electricity price diversity of GDCs. Extensive evaluations were performed based on real-world workload traces and real-life electricity price data of GDC locations. The evaluation results showed that the resource demand prediction model could predict the right amount of dynamic resource demand while achieving SLO, and also, the electricity price prediction model could provide promising accuracy. The performances of resource allocation algorithms were evaluated on CloudSim. This work contributes to minimizing the energy consumption and the average turnaround time taken to complete the task and offers cost-saving.\u0000HIGHLIGHTS\u0000\u0000SLO guaranteed, energy-efficient and cost-effective resource management framework\u0000Energy-efficient and cost-effective resource allocation (EECERA) algorithm\u0000Extensive evaluations based on real-world workload traces and real-life electricity price data of GDC locations\u0000Performances of resource allocation algorithms evaluated on CloudSim\u0000Minimizing the energy consumption and the average turnaround time taken to complete the task and also cost-saving\u0000\u0000GRAPHICAL ABSTRACT","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122583990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Lesbani, T. Taher, N. Palapa, R. Mohadi, M. Mardiyanto, M. Miksusanti, F. Arsyad
{"title":"Removal of Malachite Green Dye using Keggin Polyoxometalate Intercalated ZnAl Layered Double Hydroxide","authors":"A. Lesbani, T. Taher, N. Palapa, R. Mohadi, M. Mardiyanto, M. Miksusanti, F. Arsyad","doi":"10.48048/WJST.2021.9414","DOIUrl":"https://doi.org/10.48048/WJST.2021.9414","url":null,"abstract":"The ZnAl Layered double hydroxides (LDHs) have been successfully synthesized by the coprecipitation method, followed by intercalation using Keggin ion of α-dodecatungstosilicic acid [α-SiW12O40]4- to form ZnAl-[α-SiW12O40] LDHs. The prepared ZnAl-[SiW12O40] LDHs were characterized by using X-Ray, FTIR, and BET surface area analyses, which were, then, used as adsorbents of malachite green dye from aqueous solution. The synthesized ZnAl LDH showed a typical diffraction peak of the layered compound at 11o (003) with an interlayer space of 8.59 Å. After intercalation, it was recorded that the interlayer space of ZnAl-[SiW12O40] LDH increased to 10.65 Å. Moreover, the specific surface area of the intercalated LDH increased from 1.9685 to 14.0422 Å. The adsorption study revealed that the adsorption capacity of ZnAl-[SiW12O40] LDH toward malachite green dye was higher (37.514 mg.g-1) than the pristine ZnAl LDH (32.845 mg.g-1). The adsorption kinetics study showed that malachite green adsorption onto both pristine and intercalate LDH followed the pseudo-2nd-order model. The adsorption thermodynamic investigation indicated that adsorption of malachite green onto ZnAl-[SiW12O40] LDH was a spontaneous process and was classified as physical adsorption with activation energy ranging from 10.074 to 15.476 kJ.mol-1.\u0000HIGHLIGHTS\u0000\u0000ZnAl LDH intercalated by Keggin ion has been successfully synthesized by facile coprecipitation followed by ion exchange method\u0000The basal spacing of the intercalated ZnAl LDH increased up to 10.65 A\u0000The intercalated ZnAl LDH exhibited higher adsorption capacity for malachite green dye removal compared with the original ZnAl LDH\u0000","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116474566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. A. Naeem, Ahmed Saadoun Jaloot, M. N. Owaid, R. F. Muslim
{"title":"Green Synthesis of Gold Nanoparticles from Coprinus comatus, Agaricaceae, and the Effect of Ultraviolet Irradiation on Their Characteristics","authors":"G. A. Naeem, Ahmed Saadoun Jaloot, M. N. Owaid, R. F. Muslim","doi":"10.48048/WJST.2021.9396","DOIUrl":"https://doi.org/10.48048/WJST.2021.9396","url":null,"abstract":"The present research aims to produce gold nanoparticles (AuNPs) from the aqueous extract of locally isolated mushroom Coprinus comatus from Hit city, Iraq. Its properties were studied using the optical vision, UV-Vis, EDX, XRD, FTIR, AFM, and Zetasizer analyses. The exposure of the colloidal solution of AuNPs to UV radiation was investigated for 1, 2, and 3 h. The results showed the color change of the interaction mixture from light yellow to purple after 25 min. The lambda max of the absorbance reached 530 nm using UV-Visible spectrum as evident in the formation of AuNPs. FTIR spectra revealed the presence of functional groups related to peptides, proteins, flavonoids, monosaccharides, and phenolic compounds, which reduced gold ions. The EDX technique showed that the formed nanoparticles were AuNPs. XRD results showed that AuNPs have a face-centered cubic (fcc) crystal. The UV irradiation at different times led to an increase in the intensity of absorbance and sizes of AuNPs from 17.39 nm before the irradiation and switched to 58.16, 59.13, and 47.35 nm after 1, 2, and 3 h, respectively, but their sizes remained within the nanoscale range (less than 100 nm). In conclusion, the best result was observed after about an hour on the effects of UV irradiation on sizes of AuNPs, which reached smaller nanoparticles compared with times 2 and 3 h.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129048780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Patcharee Kammarnjassadakul, Watcharin Rangsipanuratn, Methee Sriprapun, Popchai Ngamsakulrungruj, T. Palaga, K. Sritunyalucksana, A. Chindamporn
{"title":"Cytochrome Oxidase 2 (COX2), β-Tubulin (TUB) and Chitin Synthase Subunit 2 (CHS2) Expression in Pythium insidiosum Thai Strains","authors":"Patcharee Kammarnjassadakul, Watcharin Rangsipanuratn, Methee Sriprapun, Popchai Ngamsakulrungruj, T. Palaga, K. Sritunyalucksana, A. Chindamporn","doi":"10.48048/WJST.2021.9433","DOIUrl":"https://doi.org/10.48048/WJST.2021.9433","url":null,"abstract":"This study aimed to investigate the real-time fluctuation of temperature-sensitive gene expression in a Pythium insidiosum growing at human body temperature (37 ºC) when it can cause life-threatening disease, whereas its natural habitat is in agricultural water sources with lower temperature. Genes encoding cytochrome oxidase 2 (COX2), β-tubulin (TUB), and chitin synthase subunit 2 (CHS2) were tested for their expression at the infection temperature (37 ºC) and natural habitat temperature (27 ºC) using real-time RT-PCR. Sixteen strains of P. insidiosum, representing 3 phylogeographic preferences, were analyzed. The subculturing process at 27 ºC was repeated at least 2 - 3 cycles. The results showed that at 37 ºC, the COX2 was expressed 2.5-fold higher than that of 27 ºC (p = 0.0347) while the level of TUB and CHS2 mRNA disclosed indistinguishable profiles. These results suggested that these genes were suitable to be used as housekeeping genes for temperature-susceptible gene expression studies. This work was likely to be the 1st study examining the gene expression levels of the Thai strain of P. insidiosum under thermal stress conditions. Follow-up studies for the COX2 genes may useful to provide valuable insight into the pathogenesis, diagnostic, or therapeutic targets for further investigation.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"39 24","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113936020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experiencing Moral Distress in Mental Health Nursing in Thailand","authors":"R. Upasen, Weeraphol Saengpanya","doi":"10.48048/WJST.2021.9240","DOIUrl":"https://doi.org/10.48048/WJST.2021.9240","url":null,"abstract":"Mental health nurses have to confront distressing situations in caring for patients and families, in which several predicaments can lead to moral distress. This study explored moral distress experienced by mental health nurses. A qualitative narrative inquiry was used to gain a better understanding of moral distress Together with purposive sampling and snowball methods. The data were collected from 41 mental health nurses who met the inclusion criteria through in-depth interviews and then, the data were analyzed by using content analysis. This narrative study revealed that experiences from keeping the patient safe is a significant core theme among mental health nurses, involving five themes: (1) frustration in giving best work performance, (2) concerning the patient safe, (3) being stressed at work, (4) experiencing self-condemnation, and (5) sleeping difficulty. Support needed to face moral distress was also presented in this study. The stories of moral distress from this study may contribute to the understanding of health professionals concerning how it occurs and what attributes are involved. Situations leading to moral distress and support needed can shed light on the development of policy that can prevent and help relieve moral distress among mental health nurses for a greater quality of healthcare in Thailand.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131238755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Jeenkeawpieam, Supachai Yodkeeree, S. Roytrakul, M. Pongpom
{"title":"Antifungal Properties of Protein Extracts from Thai Medicinal Plants to Opportunistic Fungal Pathogens","authors":"J. Jeenkeawpieam, Supachai Yodkeeree, S. Roytrakul, M. Pongpom","doi":"10.48048/WJST.2021.9045","DOIUrl":"https://doi.org/10.48048/WJST.2021.9045","url":null,"abstract":"Antifungal proteins or peptides (AFPs) are the natural products produced by several life forms including plants as the first-line defenses to infections. The AFPs from Thai plants can be used as new therapeutic agents in the world with growing resistance to conventional antifungals. This study determined the antifungal activities of protein extracts from Thai medicinal plants against important human opportunistic fungi, Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, and Talaromyces marneffei. Total crude protein supernatants and their precipitated proteins from 10 Thai medicinal plants with the historical usage for treatment of fungal infection were prepared. Most of the protein extracts showed antifungal activities to the tested fungi. The most effective reactivity found in the extracts from Rhinacanthus nasutus, Andrographis paniculata, and Psidium guajava by showing highest activity to T. marneffei ATCC200051 (yeast phase), followed by C. neoformans ATCC90112, C. albicans ATCC90028, T. marneffei ATCC200051 (mold phase), and A. fumigatus NCPF7367. The precipitated proteins from R. nasutus and A. paniculata containing antifungal properties were selected for partial purification by size cut-off membrane centrifugation and tested for antifungal activities. A colorimetric broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) to anti-T. marneffei. The partially purified fractions from A. paniculata, and R. nasutus showed anti-T. marneffei activity with the MIC and MFC values ranged from 2 to 128 μg/mL and 16 to >128 μg/mL, respectively. Therefore, A. paniculata and R. nasutus can be further subjected to the study of the therapeutic antifungals.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123594732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Total RNA Extraction from the Aromatic Phalaenopsis bellina, Endemic Orchid in Sabah, Borneo","authors":"Ahmad Asnawi Mus, J. Gansau, N. A. Rusdi","doi":"10.48048/WJST.2021.6553","DOIUrl":"https://doi.org/10.48048/WJST.2021.6553","url":null,"abstract":"Phalaenopsis bellina is an attractive orchid due to its unique appearance and distinctive floral fragrance. Many past studies on this plant focused on the plant at the molecular level; however, this requires sufficient quantities of high-quality P. bellina RNA. RNA is more delicate to manipulate than DNA due to its structural instability and its vulnerability to various secondary metabolites, such as polyphenols and polysaccharides. Therefore, in this study, 4 RNA isolation methods, a modified phenol-chloroform method and 3 commercial kits (Vivantis, Novogene, and Analytik Jena) were used on the leaves and flowers of P. bellina for comparison. The yield and purity of the total RNA were determined using spectrophotometry. The results showed that the total RNA isolated using the modified phenol-chloroform method had the highest yield (1223.75±68.51 ng/µL) and purity compared to the 3 commercial kits, with an OD260/280 value of 2.07 and an OD260/230 value of 2.26, respectively. In particular, the isolated RNA did not show any detectable genomic DNA contamination or other impurities. The RNA isolated using the phenol-chloroform method was also evaluated by electrophoresis, reverse transcription, and PCR. The results indicated that the phenol-chloroform method appears to be superior for total RNA extraction. Thus, this developed method is proven to be suitable for the RNA extraction of plants rich in polysaccharides and polyphenols and is amenable for future molecular studies on P. bellina.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124089123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Imjai, M. Setkit, Reyes Garcia, P. Sukontasukkul, S. Limkatanyu
{"title":"Seismic Strengthening of Low Strength Concrete Columns using High Ductile Metal Strap Confinement: A Case Study of Kindergarten School in Northern Thailand","authors":"T. Imjai, M. Setkit, Reyes Garcia, P. Sukontasukkul, S. Limkatanyu","doi":"10.48048/wjst.2020.10738","DOIUrl":"https://doi.org/10.48048/wjst.2020.10738","url":null,"abstract":"The 2014 Chaing Rai earthquake (Thailand) caused extensive damage in many reinforced concrete (RC) buildings built before the introduction of modern seismic design guidelines. Much of the damage on these buildings was attributed to the inadequate capacity and/or ductility of columns. As a result, suitable and cost-effective strengthening techniques for such substandard elements are necessary. This article presents a case study on the seismic strengthening of a one-story RC kindergarten school located in Ampor Pan, Chaing Rai province. The building was partially damaged during the afore-mentioned earthquake, which led to cracking in walls, columns, and beam-column joints. As part of the initial assessment, innovative repair solutions were sought to minimize construction time, labor, and material cost. Accordingly, an innovative strengthening technique that uses Post-tension Metal Strapping (PTMS) was proposed to strengthen the damaged RC elements. This article presents details of the structural assessment performed on the building, as well as details of the PTMS strengthening strategy, which was applied for the first time in a real full-scale structure. This article contributes towards the validation and application of the PTMS strengthening on real structures, which had not been possible until now.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"52 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120927904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Setkit, T. Imjai, U. Chaisakulkiet, Reyes Garcia, Komsan Dangyem, Katipoj Sanupong, Weerasit Chamnankit
{"title":"Torsional Strengthening of Low-Strength RC Beams with Post-Tensioned Metal Straps: An Experimental Investigation","authors":"M. Setkit, T. Imjai, U. Chaisakulkiet, Reyes Garcia, Komsan Dangyem, Katipoj Sanupong, Weerasit Chamnankit","doi":"10.48048/wjst.2020.11908","DOIUrl":"https://doi.org/10.48048/wjst.2020.11908","url":null,"abstract":"This article investigates the behaviour of low-strength reinforced concrete beams under pure torsion with and without strengthening. Four beams were cast and tested in torsion: i) a control beam without vertical reinforcement, ii) two beams with internal stirrups designed for shear and torsion demands using different stirrup spacing (50 and 100 mm), and iii) a beam having steel stirrups with a spacing of 100 mm strengthened using high ductile post-tensioned metal straps (PTMS). The main objective of the PTMS strengthening solution was to investigate the enhancement of torsional strength confined along the beam. The failure modes, torsional capacities, rotation, and strengthening performance in torsion are discussed in in this study. The experimental results indicate that the PTMS improved the cracking torque capacity by up to 15 % compared to the control beam. Moreover, the PTMS also increased the ultimate torque by up to 19 % compared to the unstrengthened beam. Current code equations to predict the torsional capacity of RC beams are also compared with the experimental results. It is found that the predictions obtained by current ACI equation gives a good agreement and yield in general conservative values compared to the experimental ones.","PeriodicalId":255195,"journal":{"name":"Walailak Journal of Science and Technology (WJST)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114274949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}