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Use Of Binary Surfactant Formulations In Low Ift Foam And Surfactant Flood, Sorrawit Tantipalakul
Use Of Binary Surfactant Formulations In Low Ift Foam And Surfactant Flood, Sorrawit Tantipalakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Viscous fingering and early breakthrough are the main problems observed during the water flooding. These problems could be overcome by using foam flooding by coinjection of surfactant solution and nitrogen gas as a mobility control in a porous media to help improve the sweep efficiency. To gain the maximum benefits of foam flooding, ultra-low interfacial tension foam was studied to obtain a foaming system with high sweep efficiency and at the same time high oil solubilization to help mobilize the oil phase from reservoir rock. In this work, mixed surfactant systems between sodium dioctylsulfosuccinate (AOT) and internal olefin sulfonate (IOS) …
Development Of A Determinant Scale Of PharmacistS Care For Herbal And Dietary Supplement Users, Mohd Shahezwan Abd Wahab
Development Of A Determinant Scale Of PharmacistS Care For Herbal And Dietary Supplement Users, Mohd Shahezwan Abd Wahab
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objective: There is a lack of instrument that is valid and reliable to measure the determinant of pharmacist's care (PCare) for herbal and dietary supplement (HDS) users. The present study aimed to develop scales to measure the determinant of PCare for HDS users and to quantify the practices. The study utilized qualitative and quantitative approaches. Methods: Three scales were developed: Direct TPB scale based on a modified Theory of Planned Behaviour (m-TPB) framework, Indirect TPB scale based on the m-TPB and beliefs elicited from community pharmacists (CPs), and PCare-HDS scale based on findings from the qualitative study. This study involved …
Taxonomy And Secondary Metabolites Of Selected Endophytic Actinomycete Strains, Nattakorn Kuncharoen
Taxonomy And Secondary Metabolites Of Selected Endophytic Actinomycete Strains, Nattakorn Kuncharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
A total of 50 endophytic actinomycetes isolated from fourteen plant species collected from six provinces of Thailand including Bangkok, Chachoengsao, Chiang Mai, Nakhon Pathom, Prachinburi and Suphan Buri were taxonomically studied relied on their phenotypic and chemotaxonomic characteristics, and the 16S rRNA gene sequence analysis. The isolates were identified as members of the family Streptomycetaceae involving Streptomyces (22 isolates), and the family Micromonosporaceae including Micromonospora (25 isolates), Plantactinospora (1 isolate) and Polymorphospora (1 isolate). Based on phenotypic characteristics, whole genome sequence analysis and DNA-DNA hybridization, 5 novel actinomycete species were proposed consisting of Micromonospora globbae (strain WPS1-2T), Micromonospora azadirachtae (strain …
Neuroprotective Effects Of The Standardized Extract Of Centella Asiatica Eca233 In Rotenone-Induced ParkinsonS Disease Model, Narudol Teerapattarakan
Neuroprotective Effects Of The Standardized Extract Of Centella Asiatica Eca233 In Rotenone-Induced ParkinsonS Disease Model, Narudol Teerapattarakan
Chulalongkorn University Theses and Dissertations (Chula ETD)
The standardized extract of Centella asiatica ECa233 consists of asiaticoside and madecassoside. Previous studies reported various pharmacological effects of, ECa233, especially in the central nervous system disorders. The present study aimed to investigate the neuroprotective effects and protective mechanisms of ECa233 against rotenone-induced neurotoxicity in rats and in neuroblastoma SH-SY5Y cells. In animal study, male Wistar rats were divided into five experimental groups (n=10); control, PD, PD-ECa10, PD-ECa30, and PD-EC100. On days 1-20, control and PD rats received 0.5% carboxymethylcellulose (CMC) (1 mL/kg, p.o.) while ECa233 10, 30 and 100 mg/kg (p.o.) were given to PD-ECa10, PD-ECa30, and PD-EC100, respectively. …
Involvement Of Nucleus Raphe Magnus In Neuronal Excitability Of Long Term Paracetamol-Treated Rats, Prangtip Potewiratnanond
Involvement Of Nucleus Raphe Magnus In Neuronal Excitability Of Long Term Paracetamol-Treated Rats, Prangtip Potewiratnanond
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study examined an involvement of nucleus raphe magnus (NRM) on neuronal excitability at cortex and trigeminal nucleus caudalis (TNC) of chronic paracetamol-treated rats. Male Wistar rats were separated into two main groups. The rats in paracetamol-treated group were intraperitoneally injected with 200 mg/kg paracetamol while 0.9% NaCl was injected in control rats for 30 days. In the first experiment, cortical spreading depression (CSD) event was initiated and direct current (DC) shift was recorded for 2 hours. Thirty minutes after CSD induction, the rats were injected with glutamate, muscimol or saline at NRM and continued signal recording. In the second …
Effect Of Citric Acid On Color Stability And Surface Roughness Of Translucent Monolithic Zirconia With Different Staining Techniques, Panisa Rinthong
Effect Of Citric Acid On Color Stability And Surface Roughness Of Translucent Monolithic Zirconia With Different Staining Techniques, Panisa Rinthong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background and rationale: Translucent monolithic zirconia is developed to solve the problem of esthetic in the conventional generation of zirconia with high opacity. When these materials are used for anterior restoration in the oral cavity, they can contact with foods and beverages that are acidic, which may affect the color stability and surface roughness of the material at different levels. Objective: The objective of this study was to determine the effects of citric acid on color stability and surface roughness of translucent monolithic zirconia with different staining techniques. Materials and Methods: A total of 80 disc specimens of VITA YZ® …
Knowledge, Attitude And Practice Towards Rational Use Of Antibiotics Among Bangladeshi Medical Tourist In Bangkok, Thailand., Kazi Sabina Arju
Knowledge, Attitude And Practice Towards Rational Use Of Antibiotics Among Bangladeshi Medical Tourist In Bangkok, Thailand., Kazi Sabina Arju
Chulalongkorn University Theses and Dissertations (Chula ETD)
Antibiotics are special drugs used for the prevention and treatment of bacterial infections. Antibiotic resistance tends to increase medical expenses, prolonged hospital stays, and increased death rate. Nowadays, antibiotic resistance is one of the most challenges to global public health. Excessive and inappropriate use of antibiotics plays an important role in increasing antibiotic resistance. Antibiotic resistance is becoming a global health problem, because the ease of international travel may increase the rapid spread of resistant microorganisms around the world. The aim of this study to strengthen the research gap and to describe the socio-demographic factor and to assess the level …
Prevalence And Factors Associated With Safe Sex Behaviors Among Adolescent Vocational Students In Nakhon Ratchasima Province, Thailand, Maneebongkot Chaumaroeng
Prevalence And Factors Associated With Safe Sex Behaviors Among Adolescent Vocational Students In Nakhon Ratchasima Province, Thailand, Maneebongkot Chaumaroeng
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: Premature sexual intercourse among adolescent can be linked to HIV and sexual transmitted diseases and unintended pregnancy. This study aimed to determine the prevalence and factors associated with safe sex behaviors among adolescent vocational students in Nakhn Ractchasima province, Thailand. Methods: A cross-sectional analytical study(n=332) was conducted from August-October 2018 by using self-administered questionnaire. Bivariate (Chi-square test) and multivariate analysis ( logistic regression) were performed to identified the factors associated with safe sex behaviors among adolescent vocational students in Nakhon Ratchasima province, Thailand. Results: finding revealed that the participants were male 57.8% and female 42.2%with an average age of …
Sexual Risk Behaviors And Sexual Harassment Among Female Beer Promoters In Chiang Mai Province, Thailand, Mathudara Phaiyarom
Sexual Risk Behaviors And Sexual Harassment Among Female Beer Promoters In Chiang Mai Province, Thailand, Mathudara Phaiyarom
Chulalongkorn University Theses and Dissertations (Chula ETD)
Beer promoters can be found throughout the country and Chiang Mai after alcohol drinks advertising was illegal according to Alcohol Beverage Control Act. From their working conditions, they are faced with sexual harassment and encourage to drink with clients which probably leads to sexual risk behaviors. There are few evidence-based researches about their sexual risk behaviors and sexual harassment so it is hard to solve these situations. This study aimed to determine their demographic data, sexual activities, attitudes, working conditions, sexual risk behaviors, and sexual harassment female beer promoters in Chiang Mai. Moreover, it aimed to find the association between …
Trends And Factors Associated With Breastfeeding In Thailand : A Secondary Analysis Of The Multiple Indicator Cluster Survey 2005-2016, Yuanpei Chen
Chulalongkorn University Theses and Dissertations (Chula ETD)
This cross-sectional study was based on secondary data of Thailand Multiple Indicator Cluster Survey (MICS round 3, 4 and 5) between 2005 and 2016 and aimed to identify trends and factors associated with breastfeeding in Thailand. Subjects were selected from the three MICS surveys and then pooled together to form final weighted samples of 9757 children under 2 years for studying early initiation of breastfeeding and 2568 children under 6 months for exclusive breastfeeding. Univariate and multivariate logistic regression analyses were applied to identify trends and factors. Results indicated that the overall breastfeeding rates were low in spite of an …
Education And Identity Of Myanmar Migrant Children In Samut Sakhon Province, Shan Li
Education And Identity Of Myanmar Migrant Children In Samut Sakhon Province, Shan Li
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of this research is to explore the educational status and identity of Myanmar migrant children in Samut Sakhon Province and to analyze the different roles and influences of formal and informal educational models on these children's identity. For Myanmar migrant children who live in Thailand, due to their living environment are different from their parents, they seem to face identity challenges. The analysis of the identifying characteristics of Myanmar migrant children is not only contributing to the understanding of the current situation of Myanmar migrant children in Thailand but also can broaden the understanding about the factors that …
From “Burmese Brides” To Burmese Wives : Analyzing Transnational Marriages Of Women From Myanmar To Chinese Men Along The Myanmar-Yunnan Frontier, Xuanyi Luo
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since around 2000, there has a growth of Myanmar women who have married men in Yunnan, China. Media reports from China, Myanmar and the West typically call these women "Burmese brides" and link them to human trafficking, fake marriages, HIV-AIDS, among other issues. This gives the public a negative impression of these women, and views them as mostly vulnerable victims caught in a faceless transnational marriage process. This thesis seeks to correct this limited view and provide a fuller picture of these women and to stress the role of their choice or "agency" in forming their transnational marriages beyond the …
New Chinese Migrants Enterpruner In Thailand: The Case Study Of Jong-Thai Jianming Eiw Ea (Group) Co., Ltd., Yuge Liu
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study of the overseas Chinese in Thailand has been broadly conducted by many scholars. However, such have mainly focused on the overseas Chinese who came from the southeastern part of China, as they were the major part of the Chinese migrants to the Southeast Asian region from the ancient to modern times, and today they still play a great role in this region. Major themes in these studies include the identification of the Chinese migrants (who they were or where they had come from), various Chinese associations, big families of Chinese entrepreneurs and etc. On the contrary, the study …
The Role Of Consumer Determinants In The Relationship Between Brand Equity And Behavioral Intentions, Hanh Tran Thi My
The Role Of Consumer Determinants In The Relationship Between Brand Equity And Behavioral Intentions, Hanh Tran Thi My
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of this study is to examine the relationship between brand equity and behavioral intentions (i.e., repurchase, recommend) as well as the moderating role of consumer determinants (i.e., trust, satisfaction, perceived electronic word-of-mouth) in this relationship within hedonic and utilitarian high-involvement product settings. The study employs a quantitative approach in which the cross-sectional survey was made to collect the data in Bangkok, Thailand. A total of 423 target samples aged from 18 to 25, studying and/or working in inner areas, were collected. The findings illustrate that brand equity is positively related to behavioral intentions in both contexts. Additionally, trust, …
Personal Branding Strategies Of Influential Youtubers And Perceptions Of Thai Millennials Toward Them, Chanamon Phansab
Personal Branding Strategies Of Influential Youtubers And Perceptions Of Thai Millennials Toward Them, Chanamon Phansab
Chulalongkorn University Theses and Dissertations (Chula ETD)
Personal branding—how individuals establish and communicate their unique traits and skills to facilitate their life goals—has become a topic of interest for many scholars and practitioners alike. One of the most widely used channels through which personal branding is executed is YouTube. There are several YouTubers, as we speak, who strive to promote their channel—their personal brand—by establishing their online identity and communicating such identity to their target audience. The studies have shown that the main target audience on YouTube, whose rising influence boosts the popularity of online video content viewing, is the millennials, especially Thai millennials as Thailand is …
The Relationship Between Facebook Users' Motivation On Environmental Issues, Environmental Awareness And Behavioral Tendency In Vietnam, Linh Nguyen Ba Tue
The Relationship Between Facebook Users' Motivation On Environmental Issues, Environmental Awareness And Behavioral Tendency In Vietnam, Linh Nguyen Ba Tue
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objectives of this research were to study the Facebook users' motivation on environmental issues, their environmental awareness and behavioral tendency in Vietnam and to explore the relationship among these three variables. Three social media influencers who had more than 10,000 followers on their Facebook profiles, demonstrated open, explicit environmentally-friendly lifestyle and achieved certain media recognition were invited to join in-depth interviews. Four hundred and fifty eight Vietnamese male and female respondents, aged between 18 and 45 years old and currently residing in Vietnam, were asked to complete an online and offline questionnaire survey. The results depicted that the respondents …
Impacts Of Communication Technology And Social Media On Intergenerational Relationships In Bangkok, Marie-Helene Thomas
Impacts Of Communication Technology And Social Media On Intergenerational Relationships In Bangkok, Marie-Helene Thomas
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objective of this research is to explore how communication technology and social media affects the intergenerational relationships between older persons and their adult children in Bangkok. Using Bengston and Schrader's (Bengtson and McChesney 1998) measurement framework for intergenerational relationships, this study examines how communication technology, namely the smart phone and its accompanying applications, Line and Facebook, has impacted the relationship between thirty older persons and their adult children. Purposive sampling was used to select participants from three elderly associations located in different neighbourhoods around Bangkok, data was collected using semi-structured interviews and data was analysed via thematic analysis. The …
The Role Of Ancestral Halls And Ancestral Worship In Chinese Clan Associations In Thailand As Forms Of Cultural Integration In The Age Of Globalization, Ying Zhang
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation focuses on studying the relationship between the ancestral hall and ancestral worship of Thai-Chinese clan associations in the context of contemporary Thai society, Thai local culture and the era of globalization. The research data mainly derives from the journals of the Thai-Chinese communities, news reports, on-site investigations and interviews. This study indicates that the Thai-Chinese had been living in Thai society and they had established Chinese traditional cultural practices in Thailand and enriched the culture of Thailand. With the development of contemporary Thai society, Thai-Chinese community associations have been transformed into non-governmental organizations and have become part of …
Genome Characterization Of Quinolone Resistance Associated Genes Of Flavobacterium Columnare Isolated From Columnaris Diseased Asian Sea Bass (Lates Calcarif)Er), Putita Chokmangmeepisarn
Genome Characterization Of Quinolone Resistance Associated Genes Of Flavobacterium Columnare Isolated From Columnaris Diseased Asian Sea Bass (Lates Calcarif)Er), Putita Chokmangmeepisarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Flavobacterium columnare is Gram negative bacteria which caused columnaris disease in various kinds of freshwater fishes. This study is the first report of F. columnare infection in freshwater culturing Asian sea bass in Thailand. Phenotypic characterization, antimicrobial susceptibility test and quinolone resistant-associated genes of F. columnare were performed. A total 15 of F. columnare were isolated from diseased fishes and phylogenetic analysis revealed that these isolates were belonged to genetic group 2 and 4. From disk diffusion test results, 5 and 6 isolates were resistant to oxolinic (OA) and nalidixic acid (NA) respectively. The highest MIC values to OA and …
Surveillance Of Influenza A Viruses In A Live Bird Market, Yangon, Myanmar During 2017-2018, Khin Thurain
Surveillance Of Influenza A Viruses In A Live Bird Market, Yangon, Myanmar During 2017-2018, Khin Thurain
Chulalongkorn University Theses and Dissertations (Chula ETD)
Live bird markets play a significant role in highly pathogenic avian influenza (HPAI) virus spread and transmission. In Myanmar, the first HPAI-H5N1 outbreak was reported in 2006. Since 2014, routine influenza A virus surveillance in LBMs have been conducted in Myanmar by the Livestock Breeding and Veterinary Department in cooperation with FAO. However, there is limited information on virus characterization and evolution of influenza viruses in Myanmar. The objectives of this thesis were to detect influenza virus subtypes circulating in different poultry species from Mingalar-Taung-Nyunt live bird market (MTN-LBM) and to determine genetic characteristics and genetic diversity of influenza A …
Appropriate Campylobacter Detection Method And Genetic Variation Of Campylobacter Jejuni In Broilers, Natnicha Phetsri
Appropriate Campylobacter Detection Method And Genetic Variation Of Campylobacter Jejuni In Broilers, Natnicha Phetsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Campylobacter has been known as an important cause of gastroenteritis in humans. The primary source is raw or undercooked poultry meat. Previous study showed that Campylobacter isolated from slaughterhouses were associated with Campylobacter isolated from broiler farms. Thus, detection of Campylobacter flock status and sorting flocks prior to slaughtering processes may help prevent Campylobacter contamination between Campylobacter-positive and negative flocks during slaughtering processes. Unfortunately, appropriate sample type and isolation method have not been clearly specified for Campylobacter detection at the farm level. Because Campylobacter are fastidious bacteria, improper detection method can attribute to false negative results. Therefore, the objectives of …
Phenotypic And Genotypic Characteristics Of Extended-Spectrum Β-Lactamase (Esbl) Production And Colistin-Resistance In Salmonella Enterica And Escherichia Coli Isolated From Pigs And Their Meat Products In The Border Provinces Between Thailand And Cambodia, Lao Pdr And Myanmar, Kyaw Phyoe Sunn
Chulalongkorn University Theses and Dissertations (Chula ETD)
A total of 809 samples of pig rectal swab from slaughterhouses (n=441) and pork from retail market (n=368) were collected in the border provinces among Thailand, Cambodia, Lao PDR and Myanmar between October 2016 and March 2017. The objective of this study was to determine resistance to extended-spectrum ß-lactams (ESBLs) and colistin in Salmonella enterica and Escherichia coli. A total of Salmonella (n=463) and E. coli (n=767) were collected and determined for the ESBL-production and for the Minimum Inhibitory Concentrations (MICs) of colistin and; the presence of ESBL gene and mcr gene. The results showed that the prevalence of Salmonella …
Genome Characterization Of Hahella Chejuensis Strain Hn01, A Pathogen Of Red Egg Disease In Tilapia (Oreochromis Sp.), Putu Cri Devischa Gallantiswara
Genome Characterization Of Hahella Chejuensis Strain Hn01, A Pathogen Of Red Egg Disease In Tilapia (Oreochromis Sp.), Putu Cri Devischa Gallantiswara
Chulalongkorn University Theses and Dissertations (Chula ETD)
Red eggs disease is an emerging disease occurred in Tilapia hatcheries which caused by a Gram-negative bacterium called Hahella chejuensis HN01. The disease infects to all the stage of fish eggs and reduces the hatchability. However, there are limited study about the bacterial pathogenicity. In this study, we analyzed the phylogenetic relationship and characterized the virulence traits of Hahella chejuensis by using genomic approach. The bacterial genome was sequenced using Illumina Miseq platform. The phylogenetic tree based on several housekeeping genes confirmed that the bacterium was belong to Genus Hahella and species chejuensis. the Average Nucleotide Identity calculation with the …
Detection Of Antimicrobial Resistance Determinants In Vibrio Parahaemolyticus Isolated From Cultivated Oysters And Estuarine Waters, Winn Khant
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, we aimed to detect antimicrobial resistance determinants and virulence factor genes in V. parahaemolyticus isolates from cultivated oysters and estuarine waters in southern Thailand. A total of 594 V. parahaemolyticus isolates were collected from pooled oysters (n=361) and estuarine waters (n=233). The samples were collected monthly between March 2016 and February 2017 from Thap Put district, Phang Nga province in southern Thailand. Confirmation of V. parahaemolyticus was carried out by PCR assay detecting species-specific (tlh) gene and the presence of virulence genes (tdh and trh). Antimicrobial susceptibility test was performed in eight antimicrobials, and the occurrence of …
Biomechanical And Biological Properties Of Cryopreserved Canine Amniotic Membrane, Nathawan Withavatpongtorn
Biomechanical And Biological Properties Of Cryopreserved Canine Amniotic Membrane, Nathawan Withavatpongtorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Amniotic membrane (AM) is the innermost fetal membrane. Due to its many known properties, human AM is a favorable corneal graft. Cryopreservation at -80ºC maintains most of biological properties. Due to shortage of supply, AM of other species are studied. The objective of this study is to explore the biomechanical and biological properties of canine AM (CAM) after cryopreservation for 7 and 30 days. CAMs were collected from healthy bitches undergoing cesarean sections. After preservation, they were tested for tensile strength by Universal Testing Machine, transparency by spectrophotometer, sterility by microbial culture, cell viability by trypan blue staining, and histological …
The Efficiency Of Pcso-524 On Feline Osteoarthritis Associated With Chronic Kidney Disease, Pemika Dulyapraphant
The Efficiency Of Pcso-524 On Feline Osteoarthritis Associated With Chronic Kidney Disease, Pemika Dulyapraphant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Twenty-six osteoarthritic cats concurrent with chronic kidney disease (CKD) enrolled in this study. All cats were divided randomly into 2 groups; control group (n=12) received placebo and treatment group (n=14) received PCSO-524 for 60 days. Cats had verified stable CKD stage II and had treated and followed up for CKD more than 3 months were included in our study. Before starting the study (day 0), all cats were taken the coxofemoral joint radiographic imaging. Only cats with the radiographic osteoarthritic lesion(s) were recruited. All of them had blood profile check-up, urinalysis, blood pressure measurement, lameness score assessment, acute and chronic …
Micro-Scale Flood Hazard Assessment In Phnom Penh, Cambodia, Naichy Sea
Micro-Scale Flood Hazard Assessment In Phnom Penh, Cambodia, Naichy Sea
Chulalongkorn University Theses and Dissertations (Chula ETD)
Water-related disasters in urban area, especially urban floods have become more frequent and severe. This leads to loss of life, infrastructure damage, business interruption as well as difficulties in conducting daily activities. Phnom Penh, the capital city of Cambodia, has frequently experienced significant rainfall-flood events during rainy season. Without proper prevention and mitigation and management of urban drainage system, Phnom Penh is expected to confront with the current and future challenge of water-related disaster. To address this urban flood issue, flood modeling could be used to assess flood severity and make a visual representation of the urban flood hazard as …
การเตรียมฟิล์มพอลิพิร์โรลบนแผ่นทองแดงโดยวิธีการพอกพูนด้วยไฟฟ้า, ธิดา คุณสมบัติ
การเตรียมฟิล์มพอลิพิร์โรลบนแผ่นทองแดงโดยวิธีการพอกพูนด้วยไฟฟ้า, ธิดา คุณสมบัติ
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ศึกษาการเตรียมฟิล์มพอลิพิร์โรล (Polypyrrole) บนแผ่นทองแดงโดยเทคนิคการพอกพูนด้วยกระแสไฟฟ้า (Electrodeposit) เพื่อทดสอบผลต่อความสามารถในการป้องกันการกัดกร่อนและค่าการนำไฟฟ้าของแผ่นทองแดงที่ผ่านการเคลือบ ศึกษาตัวแปร คือ ค่าความหนาแน่นกระแสไฟฟ้า เวลาในการพอกพูน และปริมาณผงคาร์บอน รวมถึงขนาดและรูปแบบของช่องทางการไหลของแก๊ส พบว่าชิ้นงานที่เคลือบด้วยฟิล์มพอลิพิร์โรลที่ได้จากการเตรียมในสารละลายอิเล็กโทรไลต์โดยใช้กรดโดเดซิลเบนซีนซัลโฟนิก และพอลิพิร์โรล ความเข้มข้น 0.05 และ 0.15 โมลต่อลิตร ตามลำดับ ที่ภาวะต่างกัน พบว่าที่ภาวะความหนาแน่นกระแสไฟฟ้าที่ 12.7 มิลลิแอมแปร์ต่อตารางเซนติเมตร เป็นระยะเวลา 10 นาที มีประสิทธิภาพการป้องกันการกัดกร่อนและค่าการนำไฟฟ้าที่ได้ดีที่สุด แต่เมื่อมีการเติมคาร์บอนวัลแคน 13.3 มิลลิกรัมต่อลิตร พบว่าสามารถนำไฟฟ้าได้มากขึ้นถึง 338 ซีเมนต์ต่อเซนติเมตร และป้องกันการกัดกร่อนได้ดีขึ้นถึง 0.030 มิลลิเมตรต่อปี และมีค่าความต้านทานเชิงสัมผัสเท่ากับ 0.090 มิลลิโอห์มตารางเซนติเมตร หลังจากนั้นศึกษาการเคลือบพอลิพิร์โรลบนแผ่นทองแดงที่เซาะร่อง 2 รูปแบบ คือ รูปแบบขนาน และรูปตัวยู พบว่ากระบวนการเคลือบนี้สามารถเคลือบแผ่นทองแดงที่มีการเซาะร่องได้ทั้งสองแบบรูปแบบ โดยประสิทธิภาพการป้องกันการกัดกร่อนของแผ่นทองแดงเคลือบดีขึ้น แต่ค่าการนำไฟฟ้าลดลง โดยเฉพาะการเซาะร่องแบบตัวยู
การแยกแก๊สผสมไนโตรเจน/เฮกเซน/1-บิวทีนด้วยเมมเบรนคอมพอสิตไคโตซาน, ภาณุวัฒน์ ภาวิไล
การแยกแก๊สผสมไนโตรเจน/เฮกเซน/1-บิวทีนด้วยเมมเบรนคอมพอสิตไคโตซาน, ภาณุวัฒน์ ภาวิไล
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ได้ศึกษาการแยกแก๊สผสมไนโตรเจน/เฮกเซน/1-บิวทีนด้วยเมมเบรน คอมพอสิตไคโตซานที่ผสมผสานเทคนิคการเตรียม 4 รูปแบบ ได้แก่ 1) การเติมอนุภาคซีโอไลต์ชนิด 4A ปริมาณร้อยละ 0, 1 และ 5 โดยน้ำหนักของไคโตซาน 2) การปรับความหนาของชั้นฟิล์มไคโตซาน 100 และ 50 ไมครอน 3) การใช้วัสดุฐานรองเป็นผ้าสปันบอนด์ชนิดพอลิโพรพิลีนและพอลิเอสเตอร์ และ 4) การเชื่อมขวางเมมเบรนคอมพอสิตด้วยสารละลายกรดซัลฟิวริก นอกจากนั้นยังได้ศึกษาผลการสะสมของตัวเร่งปฏิกิริยาชนิดไตรเอทิลอลูมินัม (TEAL) ที่ใช้ในกระบวนการผลิตพอลิเอทิลีนด้วยเทคโนโลยี CX บนเมมเบรนคอมพอสิตไคโตซานต่อสมรรถนะการแยกแก๊ส จากการศึกษาพบว่าเมมเบรนคอมพอสิตไม่เชื่อมขวางที่มีความหนาของชั้นฟิล์มไคโตซานหนา 100 ไมครอน ผสมผงซีโอไลต์ 4A ปริมาณร้อยละ 1 โดยน้ำหนัก และใช้วัสดุฐานรองผ้าสปันบอนด์ชนิดพอลิโพรพิลีน มีค่าแฟกเตอร์การแยกแก๊สสูงถึง 2.08±0.06 สำหรับคู่แก๊สไนโตรเจน/เฮกเซน และ 1.28±0.10 สำหรับคู่แก๊สไนโตรเจน/1-บิวทีน ในขณะที่ค่าความสามารถในการซึมผ่านแก๊สเท่ากับ 5127±745 แบร์เรอร์ เมื่อใช้อุณหภูมิดำเนินการ 10 องศาเซลเซียส ความดันแก๊สผสมขาเข้า เมมเบรน 4 บาร์ ความดันฝั่งเพอมิเอตเป็นความดันบรรยากาศ (1 บาร์) ความเข้มข้นเฮกเซนและ 1-บิวทีน ในแก๊สผสมเป็นร้อยละ 0.50 และ 4.50 โดยปริมาตร ตามลำดับ แต่ประสิทธิภาพในการแยกแก๊สของเมมเบรนจะลดลงเมื่อได้รับ TEAL และสูญเสียความสามารถในการแยกแก๊สเมื่อถูกแช่ในสารละลาย TEAL ที่ความเข้มข้นร้อยละ 5 โดยน้ำหนัก เป็นเวลา 24 ชั่วโมง
การพัฒนารูปแบบคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันโดยใช้การเรียนรู้ด้วยปัญหาเป็นฐานและเทคนิคซินเนคติกส์เพื่อเสริมสร้างความสามารถทางนวัตกรรมของนักศึกษาปริญญาบัณฑิต, โกศวัต รัตโนทยานนท์
การพัฒนารูปแบบคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันโดยใช้การเรียนรู้ด้วยปัญหาเป็นฐานและเทคนิคซินเนคติกส์เพื่อเสริมสร้างความสามารถทางนวัตกรรมของนักศึกษาปริญญาบัณฑิต, โกศวัต รัตโนทยานนท์
Chulalongkorn University Theses and Dissertations (Chula ETD)
การวิจัยในครั้งนี้มีวัตถุประสงค์เพื่อ 1) เพื่อศึกษาสภาพของนิสิต นักศึกษาด้านความรู้ ทักษะ ประสบการณ์ในการใช้คอมพิวเตอร์ อินเตอร์เน็ต สภาพการเรียนการสอนในปัจจุบันและสภาพที่มุ่งหวัง 2) เพื่อสร้างรูปแบบคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันโดยใช้การเรียนรู้ด้วยปัญหาเป็นฐานและเทคนิคซินเนคติกส์เพื่อเสริมสร้างความสามารถทางนวัตกรรมของนักศึกษาปริญญาบัณฑิต 3) เพื่อศึกษาผลการใช้รูปแบบ 4) เพื่อนำเสนอรูปแบบ ตัวอย่างที่ใช้ในการพัฒนารูปแบบ คือ ผู้เชี่ยวชาญ จำนวน 7 คน นิสิต นักศึกษาระดับปริญญาบัณฑิตจากสถาบันอุดมศึกษาภาครัฐบาลและเอกชนจำนวน 400 คน เครื่องมือที่ใช้ในการวิจัย ได้แก่ 1) แบบสอบถามความคิดเห็นของนิสิต/นักศึกษาเกี่ยวกับคุณลักษณะของผู้เรียนด้านความรู้ ทักษะและประสบการณ์ในการใช้คอมพิวเตอร์และอินเทอร์เน็ตและสภาพการเรียนการสอนในปัจจุบัน 2) แบบประเมินโดยใช้เกณฑ์ประเมินความสามารถทางนวัตกรรมแบบรูบริค 3) แบบประเมินรับรองรูปแบบ 4) แบบสอบถามความพึงพอใจของนักศึกษาที่เรียนจากรูปแบบ โดยกลุ่มตัวอย่างได้แก่ นักศึกษาระดับปริญญาบัณฑิตจำนวน 30 คน เครื่องมือที่ใช้ในการวิจัย ได้แก่ 1) ระบบคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันฯ และ 2) เกณฑ์วัดและประเมินความสามารถทางนวัตกรรมแบบรูบริค ใช้ระยะเวลาทดลอง 8 ครั้ง วิเคราะห์ข้อมูลด้วยค่าความถี่ ร้อยละ ค่าเฉลี่ย ส่วนเบี่ยงเบนมาตรฐาน ใช้การวิเคราะห์ค่า ANOVA รูปแบบการวิเคราะห์ความแปรปรวนแบบวัดซ้ำ (Repeated Measures Designs) ผลการวิจัยสรุปได้ว่า 1. รูปแบบคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันโดยใช้การเรียนรู้ด้วยปัญหาเป็นฐานและเทคนิคซินเนคติกส์เพื่อเสริมสร้างความสามารถทางนวัตกรรมของนักศึกษาปริญญาบัณฑิต ประกอบด้วย 6 องค์ประกอบ ได้แก่ 1) วิธีการเรียนการสอน 2) เนื้อหา 3) แหล่งทรัพยากรเรียนรู้ 4) การวัดและประเมิน 5) ผู้อำนวยความสะดวก 6) เครื่องมือคอมพิวเตอร์สนับสนุนการเรียนรู้ร่วมกันและสื่อ โดยมี 8 ขั้นตอน ได้แก่ 1) การรับรู้และให้คำนิยามของปัญหา 2) การวิเคราะห์ 3) การอภิปราย 4) การกำหนดแนวทางแก้ปัญหา 5) การค้นคว้าและเก็บรวบรวมข้อมูล 6) การแก้ปัญหา 7) การแบ่งปัน และ 8) การวัดและประเมินผล 2. …