จำนวน Repository ( 77 )
Development of bone replacement material via nanohydroxyapatite crystal growth on silk fibroin fiber
The objective of this research is to propose a new way to fabricate a composite material for future bone replacement development via growing apatite crystal on silk fibroin fiber. Apatite crystallization on silk fibroin fiber was prepared by precipitation reaction between Ca(NO3)2 solution and (NH4)2HPO4 solution adjusted pH by NH4OH solution. In this work Effect of solution concentration and initial pH values was investigated on apatite crystals. Chicken eggshells were used as calcium source by heating sufficiently powdered eggshells at 1300 °C for 4 h to acquire CaO powders made Ca(NO3)2 solution by dissolving in 65% HNO3 solution. Prepared Ca(NO3)2 solutions were adjusted concentration as 3 levels and were adjusted different pH values of 7 8 and 9 respectively. For processing of apatite crystallization silk fibroin fibers were immersed in Ca(NO3)2 solutions for 30 min. After that (NH4)2HPO4 solutions were added in silk fibroin fibers immersed in Ca(NO3)2 solutions. Reaction time was fixed about 1 min before cleaning to remove impurity precipitates on surface of silk fibroin fiber. Finally apatite crystallization on silk fibroin fibers occurred. The obtained result can conclude morphologies of apatite crystals on silk fibroin fibers was sheets sphere and flower. Solution concentrations and initial pH values directly influenced on Ca/P ratio of obtained apatite crystals by Ca/P ratio increases as increased solution concentrations or increased pH values. Finally research silk fibroin fibers were woven as two patterns of plain weave and twill weave and they were investigated Young’s modulus and tensile strength. The result indicates that Young’s modulus of silk fibroin fiber sheets woven as twill weave and as plain weave were about 616 MPa and 425 Mpa and tensile strengths of them weave were about 40 Mpa and 72 Mpa respectively. The optimum condition of growing apatite crystals on silk fibroin fibers was sample of CP19. Design of silk fibroin fiber with plain weave was an optimum pattern for future biomedical applicaions.
Enhancement quality of rice seed by using bio-extract fermented from pig placenta and by using wood vinegar
This study was undertaken to determine effect of bio-extract fermented from pig placenta and effect of wood vinegar solutions on seed germination percentage and speed of germination of 2 rice cultivars Chai Nat 1 and Sang Yod Phattalung. The experiment was conducted in factorial in completely randomized design with 2 factors and 4 replications. The first factor was ratios of the solutions to water and the second was duration for seed incubation. The results demonstrated that wood vinegar showed more positive effect on rice seed germination performances than that of bio-extract. Speed of germination was affected by an inter-action between the dilutions of the solutions and the duration for seed incubation. In Chai nat 1 experiment the seed soaked in 20 times dilution of bio-extract and subsequently incubated for 24 hrs increased speed of germination of the seed. While soaking the seed in 400 times dilution of wood vinegar and incubated for 24 hrs could enhance both percentage and speed of the seed germination. In Sang Yod Phattalung experiment soaking the seed in 50 times dilution of bio-extract and subsequently incubated for 48 hrs or soaking the seed in 300 times dilution of wood vinegar and incubated for 48 hrs could enhance both percentage and speed of seed germination. According to the results we concluded that soaking rice seed in bio-extract of pig placenta fermentation or in wood vinegar solutions could enhance the seed quality.
Preparation of polymer blends fiber between poly (lactic acid) and poly (butylene succinate) for textile applications
Biodegradable polymer blend fibers were prepared by melt spinning technique. Poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) were blended in a twin screw extruder at various contents of PBS at 0-50 wt%. PLA/PBS blends were melt spun using a single screw extruder equipped with multifilaments spinnerette. The effect of PBS contents on morphology thermal properties and mechanical performance of PLA/PBS blend fiber was investigated. SEM micrographs indicated that the addition of PBS at 10 wt% showed miscibility of PLA/PBS blends while the other contents of PBS exhibited phase separation of the blends. The incorporation of PBS affected on the declination of crystallinity in the blends. It can be noted that the addition of PBS could enhance the elasticity of PLA/PBS blend fibers.
Problem of vacational knowledge and abilities job. training of hospitality according to the workplaces notice : a case study of students, faculty of .liberal arts, Rajamagala University of Technology srivijaya in summer
This research aimed to investigate the students’ professional problems during their internship from the perception of workplace. The population was 66 informants who the sample was 43 selected by purposive quota sampling Research data were analyzed by descriptive statistics percentage mean and standard deviation and multiple regression analysis The research finding showed the findings showed that (1) the students’ fundamental proficiency problems in front office department were overall at the “Little Level”. A questionnaire 3 dimensions: the students’ fundamental proficiency core proficiency and additional proficiency problems. (2) The students’ fundamental proficiency problems in food and beverage department were overall at the “Little Level”. A questionnaire 3 dimensions: the students’ fundamental proficiency core proficiency and additional proficiency problems. (3) The students’ fundamental proficiency problems in housekeeping department were overall at the “Moderate Level”. A questionnaire 3 dimensions: the students’ fundamental proficiency core proficiency and additional proficiency problems.
Problems and barriers for cooperative education student trainee recruitment according to the work place's concept. : a case study of undergraduates of business administration faculty, Rajamangala University of Technology Phra Nakhon
This abstract is aimed to study the problems and barriers in receiving the business administration students into co-operative education apprentice in accordance with the firms’ ideas on organizing and working processes qualifications knowledge and competence in the field of study. Population is the entrepreneurs or controllers who accept 180 fourth-year students of academic year 2255 to the internship programme. The data collection is using questionnaires. Statistics used in the data analysis are percentile means and stand deviation. The research results are as followed: 1. The problems and barriers on organizing and working process are at the high level. This implies that the firms are unable to coordinate with the institution to define and get the students ready before implementing.2. The problems and barriers on the qualifications of cooperative study students are at the high level. This implies that those students are unable to make decision to solve problems during internship. 3. The problems and barriers on knowledge and competence in their fields of study are at the high level. This implies that students are unable to communicate well both verbally and alphabetically in Thai and foreign languages.