bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison Of Single-Dose And Multi-Dose Antibiotic Prophylaxis In Orthognathic Surgery: A Retrospective Cohort Study
Authors:   , Pochana Teeraphat
Published: September 2023

Objective: (1) to compare the prophylactic effect of a single versus a multiple dose antibiotic regimens and (2) to determine factors related to surgical site infection in orthognathic surgery. Materials and methods: Medical records of patients underwent orthognathic surgery in the Faculty of Dentistry, Chulalongkorn University between 2014 and 2016 were extracted for medical data including demographic data, American Society of Anesthesiologists (ASA)-classified past medical history, orthognathic surgical procedures and complications, prophylactic antibiotic regimen, and surgical site infection. The records also contained 30-day follow-up information, according to the Centers for Disease Control and Prevention (CDC) diagnostic criteria for surgical site infection. Results: Of 168 patients, three developed signs of infection and four presented maxillary sinusitis. In the infected group, one received 1.2g single-dose intravenous amoxicillin-clavulanate at induction while the remaining two patients were administered with 2 million units intravenous penicillin G every 4 hours perioperatively and one out of two received 1g oral amoxicillin twice a day for a week postoperatively. No significant association was found between types of antibiotic prophylaxis and surgical site infection (p = 0.472). Prolonged operation time significantly increased the risk of infection (p = 0.030). There was no significant difference in infection among other factors including age, gender, ASA score, smoking behavior, orthognathic surgical operations, blood loss, blood transfusion, bone grafting and bad split. Moreover, there was no significant association between contributing factors related to surgical site infection and postoperative maxillary sinusitis. Conclusion: The results suggest that the single-dose antibiotic prophylaxis can be sufficient in prevention of surgical site infection. Prolonged operation time increases the risk of infection.
TLR3 signaling modulates immunomodulatory property of human periodontal ligament stem cells.
Authors:   , Chaikiawkeaw Daneeya
Published: September 2023

Toll like receptor 3 (TLR3) is a member of TLR family functions to recognizes double-stranded RNA (dsRNA) produced by positive-strand RNA viruses and DNA virusesand generate signaling that stimulate body immune system against virus infection. However, recent evidence suggests that TLR3 signaling may also play a role in initiating the immunosuppressive property of the cells. Study on skin regeneration has shown the anti-inflammatory responses of keratinocytes required for wound healing andthe increasing number of hair follicle formation after TLR3 signaling was activated by fragment of RNA released from damaged cells. Moreover, activation of TLR3 signaling have shown to elicit a higher success rate and lower side-effect for a grafted surgery in animal models. Taken together, TLR3 signaling may play an important role in immunomodulatory property of the cells. The aim of this study is to investigate the involvement of TLR3 signaling on immunomodulatory properties in periodontal ligament stem cells (PDLSCs).  PDLSCs expressed TLR3, however, detailed mechanism in which TLR3 signaling modulate immunomodulatory property of PDLSCs has not yet been identified. PDLSCs were established from is periodontal tissue and expressed several multipotent stem cells markers. These cells could also differentiate under appropriate culture conditions. After activation with poly(I:C), a potent activator of TLR3, the expression of interferon-gamma, IDO (indolamine 2,3 dioxygenase) and HLA-G (human leukocyte antigen G), three major molecules that participate in the immunomodulatory function.  Addition of bafilomycin A, a chemical inhibitor that prevent the cytoplasmic acidity, could inhibit this inductive property, indicating that activated TLR3 were located in cytoplasmic endosome. RNA silencing approaches could also abolish the inductive effect of poly(I:C) confirming the role of TLR3.  Furthermore, the co-culture between poly(I:C)-treated PDLSCs and PBMCs was performed.  The results showed the inhibitory effect of PBMCs and the upregulation of FOXO3, a marker of T-regulatory cells support the immunomodulatory role of PDLSCs after activated with poly(I:C). The knowledge from this study will provide more understanding on TLR3-induced immunosuppressive property on PDLSCs that could lead to the clinical application for stem cells therapy in the future.
The effect of disking technique on proximal caries of primary upper incisors in tribal preschool children attending child development Centers of Mae Fah Luang district, and Doi Tung development project, Chiang Rai
Authors:   , Thanaboonyang Niwat
Published: September 2023

Aim: To evaluate the effect of disking technique and resin modified glass ionomer cement (RMGI) restoration on proximal caries of primary upper incisors in tribal preschool children, aged 3-5 years, attending child development centers of Doi Tung Development Project, Chiang Rai. Methods: Twenty tribal preschool children were enrolled in this match-paired design study. Twenty-six proximal carious surfaces were randomized for RMGI restoration (control group), and 26 proximal carious surfaces were randomized for disking technique (experimental group). Fluoride varnish was applied in both groups after treatment. At 6-month interval, the treatment success was evaluated including retention of restoration, marginal integrity, no progression of caries and no periapical pathology. Fisher’s exact test was used for analysis. Statistical significance was set at p<0.05. Results: After 6 months, 22 (85.0%) RMGI restorations still survived, and 25 (96%) RMGI restorations revealed normal periapical area. In disking group, no caries progression was found among the 24 surfaces (92%), all of disking teeth (100%) revealed normal periapical area. There was no statistically significant difference in clinical and radiographic outcomes between these methods (p=1.000). Conclusion: In proximal caries management of primary upper incisors limited to dentin outer  third and dentin middle third by RMGI restoration and disking technique, no statistically significant difference was found in clinical and radiographic outcomes at 6-month interval.
Green composites of polylactic acid filled with natural fiber for biodegradation application
Authors:   , Yamoum Chamaiporn
Published: September 2023

This research focuses on how to use natural fibers available from agricultural residues to produce biodegradable materials such as mulch films. Green composites were prepared from natural fibers (peanut shell and bagasse fiber) and polylactic acid (PLA) together with plasticizers. The presence of plasticizers improved PLA molecular mobility as seen by the reduction of glass transition, cold crystallization, and melting temperatures. The addition of natural fibers into PLA brought down decomposition temperature when compared to PLA. The morphological study of the composites showed poor interfacial adhesion between natural fibers and PLA matrix. Moreover, the loading of plasticizers improved distribution of natural fibers in PLA matrix. The composites revealed that tensile strength decreased while Young’s modulus increased with increasing natural fibers content. The added plasticizers into the composites showed increase elongation at break and impact strength. Thermo−mechanical properties revealed improvement of PLA performance at high temperature use by the addition of natural fibers together with plasticizers due to cold crystallization at a high temperature, which developed high storage modulus. The composites showed low water vapor permeability which reduced moisture loss by evaporation and increased the efficiency of water use. The enhancements in degradation of the composites were due to the presence of natural fibers. Furthermore, the study of chemical crosslinking PLA in the presence of crosslinking agent showed that the optimum of thermal, thermo–mechanical, and rheological properties were at 5 phr crosslinking agent content.
Production of biojet fuel from palm fatty acid distillate over Ni/HZSM-12 catalyst
Authors:   , Hiranyasiri Chayanee
Published: September 2023

Generally, jet fuels are mainly derived from the refining of petroleum feedstock which exhaust greenhouse gases. Therefore, biojet fuel is introduced as an alternative way to solve the problem. Moreover, jet fuel must have a freezing point about -47 °C or below so iso-paraffins which have low freezing point are required. In this study, the hydroprocessing of palm fatty acid distillate (PFAD) over synthesized Ni/HZSM-12 and conventional Ni/HY catalysts which have different morphology and pore size for producing biojet fuel (hydrocarbon in a range of C9-C14) was studied in a continuous flow fixed-bed reactor under conditions of 350-400 °C, 10-30 bar, LHSV of 1.5-2.5 h-1, and H2/feed molar ratio of 10. The main reactions are hydrodeoxygenation in order to remove oxygens in the fatty acid molecules then followed by hydroisomerization and hydrocracking reaction. The fresh catalysts were characterized by XRD, XRF, TEM, BET, TPR and TPD. For Ni/HZSM-12 catalyst, the optimal reaction condition was found at 375 °C, 30 bar, LHSV of 1.5 h-1 and H2/feed molar ratio of 10 over 10 wt.% Ni/HZSM-12 catalyst. The results show that Ni/HZSM-12 catalyst exhibited higher biojet yield as compared to Ni/HY catalyst (53 and 21%, respectively) and provided higher selectivity to produce iso-paraffin products at optimal condition because HZSM-12 had had narrower pore size so it predominately produced the lighter cracked products and provided iso-products. Moreover, Ni/HZSM-12 had low coke formation which is characterized by TPO, corresponding to the high stability of HZSM-12 catalyst.
Methane and carbon dioxide adsorption on al-based and Zr-BASED Mofs: effects of amino-functionalization
Authors:   , Lamoonkit Orawee
Published: September 2023

For natural gas storage, adsorbed natural gas (ANG) technology has attracted great attention. There is a wide range of porous materials for ANG, but the most promising porous adsorbents for natural gas are metal organic frameworks (MOFs). This study examined adsorption of carbon dioxide and methane gases on aluminium (Al) based MOFs and zirconium (Zr) based MOFs including MIL-53(Al), MIL-53(Al)-NH₂, UiO-66, UiO-66-NH₂ 25%, UiO-66-NH₂ 50%, UiO-66-NH₂ 75%, and UiO-66-NH₂. Experiments were carried out in a static system at 33°C and pressures up to 100 psi. Characterization and structural analysis of the adsorbents were investigated by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), and N₂ adsorption/ desorption. The effects of amino functionalization on MIL-53(Al) and UiO-66 were discussed. The results showed that increasing the pressure led to the increase in methane and carbon dioxide adsorption. Moreover, the addition of amino functional group decreased the surface area and micropore volume but did not affect the crystalline structure. MIL-53(Al) and UiO-66-NH₂ displayed similar methane and carbon dioxide uptake, which was higher than the others. It seems that the high surface area and the effect of amino group on UiO-66-NH₂ contributed to the high methane and carbon dioxide adsorption. Furthermore, the carbon dioxide uptake was higher than the methane uptake, approximately two times due to its electrophile, which resulted in preferential adsorption toward carbon dioxide.
Optimization algorithm study : mixed integer linear programming
Authors:   , Fongchantuk Tittawat
Published: September 2023

In the present, many petrochemical and petroleum products (engine fuel, solvent, plastic and synthetic rubber. etc.) are important. They are transported by ship, pipe line or train every day. So, minimizing transportation cost and time or maximizing profit is an important key of every company. In this optimization process, the optimal supply chain must be well developed in mathematical programming with the objective function of minimum cost or maximum profit and be solved by using optimization solvers. Objective functions and their constraints are solved by suitable types of optimization solvers: Linear programming (LP) and mixed integer linear programming (MILP). MILP is one of the most widely used optimization technique for designing supply chain, and developed by using linear programming and branch-and-bound technique. In this research, MILP algorithm is studied and developed on FORTRAN 4.0 to study MILP procedure, and then it is applied with case study of biofuel production supply chain. Finally, the results are validated with solver in Microsoft Excel. The result shows that the MILP algorithm can show many solutions with one optimum point for multiple optimum problems for benefit of alternative solutions, while only one solution is obtained from solver in Microsoft Excel. Moreover, the optimal SCNPV from the algorithm is close to one from Microsoft Excel. It shows that the MILP algorithm is high efficient for accuracy solution and benefit for alternative of suitable solutions in optimizing supply chain problems.
Preparation of alginate capsule using two coaxial glass-tube
Authors:   , Watchanung Panida
Published: September 2023

TEMPO-Oxidized bacterial cellulose (TOBC) were obtained using TEMPO-mediated oxidation (TOBC) to produce carboxylate groups on bacterial cellulose surfaces. TOBC had lower crystallinity but better aqueous dispersion than bacterial cellulose. TOBC was used as a reinforcement agent for production alginate capsules. The alginate capsules for entrapping rice bran oil were made via a coaxial-glass tube. The factors that influenced on the shape and production efficiency of capsules were the gap between tube tip and the Ca2+ ions bath and the viscosity of shell solution. However, these factors had no effect on the size and shell thickness of capsules. Increasing of TOBC content enhanced the turbidity and compression strength of shell and gave smoother surface. The TOBC-alginate film was fabricated to easier characterization the shell property. More TOBC content can decrease the shrinkage of films, increase mechanical property and oxygen transmission rate, but had no effect on thermal and water vapor transmission rate. The carboxyl group of TOBC can participate crosslinking with Ca2+ and act as the structural construction of the alginate.
Adsorption of methane and carbon dioxide on activated carbon and metal organic frameworks
Authors:   , Sudsuansi Chutima
Published: September 2023

Natural gas has gain popularity for transportation among other fuels since it is the cleanest burning fossil fuel. However, the important challenge for utilizing natural gas is its comparatively low volumetric energy storage density. Consequently, a suitable natural gas storage is needed. Adsorbed natural gas (ANG) is an interesting alternative because it could be expected to reduce the cost and potential damage from compressed natural gas (CNG) and liquefied natural gas (LNG) technology. Comparative adsorption of methane and carbon dioxide on activated carbon ZIF-8, UiO-66, and MIL-53 (Al) was investigated at 35 °C and up to 100 psi. The addition of PVDF in ZIF-8 and activated carbon were also studied including 75 wt% ZIF-8, 50 wt% ZIF-8, 25 wt% ZIF-8, 50 wt% ZIF-8, and 25 wt% ZIF-8. The result shows that the methane and carbon dioxide adsorption increase with the pressure. MIL-53 shows the highest methane and carbon dioxide adsorption. The high surface area and micropore volume corresponds to the high methane and carbon dioxide adsorption. However, the high micropore volume to total pore volume ratio also contributes to higher methane adsorption in the case of ZIF-8 and UiO-66. ZIF-8 has higher methane adsorption than UiO-66 although they have about the same surface area and micropore volume. On the contrary, UiO-66 has higher carbon dioxide adsorption than ZIF-8 affecting from chemical properties such as an open metal site and an organic ligand. Moreover, ZIF-8 has the highest CH4/CO2 selectively because it has high surface area, high micropore volume, high micropore volume to total pore volume ratio, and proper open metal site and organic ligand.
Heat exchanger network retrofit under fouling effect
Authors:   , Yanyongsak Jaturaporn
Published: September 2023

The energy conservation by heat exchanger network (HEN) is important in process design according to an increase of energy costs and global environmental concerns. To minimize the energy consumption with positive net present value (NPV), the retrofitted HEN plays an important role in process energy systems. The HEN retrofit model is based on stage-wise superstructure by Yee and Grossmann (1990). In addition, fouling deposition on the surface area of heat exchangers causes extra energy consumption, production loss and maintenance costs. The new proposed model is retrofitting HEN with fouling effects. This method achieves HEN with the optimal trade-offs between energy savings, and investment over operating period. For cleaning schedule, retrofitted HEN shows better capability to recover heat and NPV higher than base-case considered from a lower number of cleaning requirement. In this study, the proposed model is combined between cleaning schedule strategy and HEN retrofitting with fouling effect to achieve profitable HEN.
Methane hydrate formation and dissociation : roles of promoters
Authors:   , Neak Kimhak
Published: September 2023

Roles of promoters become necessary in methane hydrate formation for the attempt of gas storage application, but some additives might cause unwanted results in gas recovery. The effects of amino acids (l-leucine and l-valine) and surfactants, sodium dodecyl sulfate (SDS), and methyl ester sulfonate (MES) was investigated at 8 MPa and 2 to 4 °C. L-leucine system enhanced hydrate formation because of its surface activity and surface adsorption at interfaces. A noticeable methane uptake yield was also observed in the l-valine solution. Its influences might be from the nature of l-valine that has non-polar, aliphatic hydrophobic side chain resulting in lower surface activity or surface adsorption at gas/liquid interfaces. Moreover, synergism between MES and SDS was observed with fast kinetics and high gas uptake because of micelle formation to lower the interfacial tension in the solution. At the same scale of the concentration, 0.23 wt% (CMC-SDS), amino acids cannot achieve methane hydrate formation compared to surfactants. The comparison of promoting an effect of each promoter at the optimum concentrations was exhibited by using 0.5 wt% l-leucine, 0.7 wt% l-valine, 0.23 wt% and 0.12 wt%. Although every promotor was possible to achieve high methane uptake, its pros and cons were clearly indicated. The formation with the amino acids was found with much slower formation rate. However, dissociated gas from the surfactants caused a lot of foam that could against the gas release, taking for a longer time to complete the gas recovery, and losing the amount of surfactant. Unlike the surfactants, methane could be recovered from the hydrate formed with the amino acids at a faster rate and reusability.
Optimization of single refrigerant conocophillips lng cascade process
Authors:   , Saetang Naken
Published: September 2023

An LNG cascade process operates under high pressure and extremely low temperature to liquefy natural gas, requiring very high work input to the compressors. This thesis performed the optimization of the single refrigerant ConocoPhillips LNG process by a global optimization technique based on the domain and image partitioning methodology (Faria and Bagajewicz, 2012) to minimize work input to the system. The procedure consists of an NLP upper bound and MILP lower bound models. The lower bound model was formulated by discretizing and linear relaxation of the upper bound non-linear equations by assigning new integer variables and a set of linear constraints. To guarantee the global optimum, the difference between objective function of the upper and lower bound model must be small. The ConocoPhillips LNG process consists of three liquefaction loops which are propane, ethylene and methane loops. Thermodynamic properties prediction model consisted of a metamodel based on quadratic polynomials regressed from Peng-Robinson EOS. Several minimum approach temperatures were performed and the results showed that the lowest approach temperature of 3 K was the most efficient case that gave the lowest refrigerant flowrates, and the lowest total work input to the compressors. A simple cost analysis was performed both CAPEX and OPEX. The problem was solved in GAMS and the results were verified by PRO/II simulation software.
Energy and exergy analysis for cryogenic process design/retrofit
Authors:   , Threerachannarong Nattawat
Published: September 2023

Energy and Exergy analysis are one of alternative techniques to analyze chemical processes in term of energy quality parameters such as enthalpy, entropy and exergetic temperature. The exergetic temperature can conduct Exergy Composite Curves diagram (ECCs) (Marmolejo-Correa, 2012) which represents exergy targets: exergy requirement, exergy rejection and exergy destruction etc. In addition, these targets can be used for improving processes. The strength points of these analysis are to design the new process and to improve the utility performance. Therefore, these analysis methods have been applied to low-temperature process that requires a large amount of energy consumption. In this work, there are two approaches of energy minimization. First model, a combination with ECCs diagram and mathematical programing (Wechsung, 2011) can synthesize a better design of process to reduce utility usage. Second model, a synthesis of cascade refrigeration systems (Colmenares, 1989) can indicate a configuration of refrigeration systems with alternative working fluids for minimizing the energy used by condenser and compressor. Besides that, these models were applied to a liquefied natural gas (LNG) production as a case study which comes from the Pro/II’s tutorial (commercial engineering software). The results show that the Exergy and Energy analysis have an ability and potential to design new synthesis for cooling systems for sub-ambient processes and a combination of heat exchanger with compression and expansion processes.
Development of LCSoft as a tool for life cycle assessment of environmental impacts : incorporating additional LCIA methodologies and environmental footprint
Authors:   , Rattanatum Tanathip
Published: September 2023

Life Cycle Assessment (LCA) is a technique to calculate, assess, and analyze environmental impacts through the entire life cycle of products. LCSoft has been continuously developed as LCA software which has ability to integrate with other software e.g. process simulation software and economic analysis software. In addition, LCSoft has several functions which can analyse various environmental effects such as sensitivity analysis, alternative comparison, and eco efficiency analysis. In this thesis, several features were added into LCSoft to cover a wider application range from users and more industrial technologies. This thesis consists of four main parts. First, adding more essential equipment of industry and more operating conditions of column. Second, adding more LCIA methodologies to calculate environmental impacts of product. Third, including more impact assessment related to ecosystem by adding water scarcity footprint and ecological footprint. The last part is the validation of modification results by using two case studies: bioethanol from cassava rhizome and dimethyl carbonate from carbon dioxide capture and utilization process. By comparing with SimaPro v.8.3, the results calculated from LCSoft show that the new version of LCSoft has an ability to assess the environmental impacts precisely with the new features. Validation using two case studies proves that LCSoft can be efficiently used to assess environment impacts from both biochemical and petrochemical processes.
Furfurylamine-based polybenzoxazine adsorbent for CO2 capture: effect of carbonization temperature and activation methods
Authors:   , Vongtiang Thanabhumi
Published: September 2023

Carbon sorbents are of interest for post-combustion CO₂ capture. Polymers are one of the potential precursors to develop carbon adsorbent with suitable surface functionalities. In this research, furfurylamine-based polybezoxazine was used to produce the carbon adsorbent because of its superior properties such as high char yield, high thermal stability, and low water adsorption. To obtain the carbon adsorbent, benzoxazine monomer was prepared by using furfurylamine, paraformaldehyde, and phenol. Polymerization by a sol-gel technique using xylene as a solvent was employed. The obtained polymer was carbonized at various temperatures: 600, 700, and 800 °C. Physical and chemical activation were then conducted at 900 °C by using CO₂ and KOH as an activating agent, respectively. The CO₂ adsorption performance was conducted using a volumetric method at 40, 70, and 110 °C. The results show that both surface morphology and functionalities play a key role in CO₂ adsorption performance. Chemical activation gave the carbon adsorbent with higher surface area and pore volume than the physical activated adsorbents. The conversion of pyridinic functionalities to pyrrolic and pyridonic functionalities was revealed in the XPS analysis in both adsorbents activated by chemical and physical methods. The adsorbent carbonized at 800 °C and activated and chemical activated gave the highest CO₂ adsorption capacity at all adsorption temperatures as a result of its high surface area (1,273 m²/g), high pore volume (0.537 cm³/g micropore volume and 0.7891 cm³/g total pore volume) and suitable surface functionalities.
Designing binary low IFT surfactant system using HLD concept for oil recovery
Authors:   , Jamprakhon Tukta
Published: September 2023

Surfactant-based microemulsion technology is widely used in tertiary enhanced oil recovery applications (EOR). The formulation of suitable surfactant system is a key success in production and economic feasibility of this technology. The middle phase or Winsor Type III microemulsions, employed for selecting appropriate surfactant system, can offer an optimal salinity at which the high oil solubilization capacity and minimum interfacial tension (IFT) or ultralow IFT (<0.01 mN/m) are obtained. By this technology, more remaining oil in the reservoir can be solubilized and mobilized which leads to an improvement of oil recovery. This study aims to formulate surfactant systems for the oil recovery through microemulsion formulation. The novel mixed anionic surfactant system of a sodium dioctyl sulfosuccinate (AOT) and an internal olefin sulfonates (IOS) with different alkyl chain lengths (C15-18, C19-23, C24-28) were used due to its mixture avoiding the surfactant precipitation. The result found that the binary mixture of AOT and (IOS C15-18 and IOS C19-23) can form the middle phase at the mixing ratios of 5:5 to 9:1 (by molar ratio) with heptane and decane. When the fraction of IOS increased in the mixed AOT/IOS system, the optimal salinity (S*) also increased. For the effects of a carbon tail length of IOS surfactant was observed that the tail length increased with decreasing the optimal salinity. The hydrophilic–lipophilic deviation (HLD) for the mixed surfactant system was investigated to individually determine the K and Cc values for the IOS surfactants. The finding from this work provided a guide for surfactant selection through HLD concept to formulate microemulsion-based surfactant flooding for EOR application.
Taxonomic revision of the fern family athyriaceae in Thailand
Authors:   , Pongkai Puttamon
Published: September 2023

The most up-to-date account of the Athyriaceae is in Flora of Thailand. This account includes seven genera, i.e. Athyrium, Anisocampium, Cornopteris, Deparia, Diplazium, Hypodematium and Kuniwatsukia. Previously, the taxonomic relationships among genera were ambiguous and not well understood. The existing keys and descriptions are uncertain and do not include some unknown taxa. This research aims to clarify the taxonomic status of this family and its genera based on morphological, anatomical, palynological and molecular data. The results indicated that the types and shapes of frond, scale types, sorus shapes, shapes of vascular bundle and ornamentation of spores are valuable characters for genus and species determination. The molecular results are congruent with other previous results that the Athyriaceae consisted of 5 genera, i.e. Athyrium, Anisocampium, Cornopteris, Deparia and Diplazium. The genus Kuniwatsukia was merged with Anisocampium and the genus Hypodematium was excluded from the Athyriaceae. In all, forty seven species of athyriaceous fern and four species of Hypodematium were recognized. Of these, two new species, namely Hypodematium boonkerdii Pongkai, Li Bing Zhang & Pollawatn and Diplazium thailandicum Pongkai, Boonkerd & Pollawatn were published. Eight new records were reported, i.e. Anisocampium niponicum (Mett.) Hance., Athyrium biserrulatum Christ, A. brevisorum (Wall. ex Hook.) T. Moore, A. pachyphyllum Ching, A. wangii Ching, Diplazium bellum (C.B. Clarke) Bir, D. pallidum (Blume) T. Moore and D. procumbens Holttum. The name: D. bellum (C.B. Clarke) Bir. and D. petelotii Tardieu are lectotypified. Diplazium axillare Ching was considered a synonym of D. bellum (C.B. Clarke) Bir. Key to the genera and key to the species were re-constructed, together with descriptions, line drawings and distribution.
Effect of Cu(In,Ga)₃Se₅ ultra-thin layer on optical properties and photovoltaic efficiency of Cu(In,Ga)Se₂ thin film solar cells
Authors:   , Namnuan Boonyaluk
Published: September 2023

Cu(In,Ga)3Se5 (135-CIGS) layers with various thicknesses were deposited on the surface of ~1.8 micron thick Cu(In,Ga)Se2 (112-CIGS) photon absorber in the fabrication of CIGS thin film solar cells. This significantly affects the shift of the optical band gap energy from 1.15 eV (112-CIGS) to 1.19 eV, with only 10 nm thick of 135-CIGS capping layer, leading to the increase in the open-circuit voltage (Voc) of the solar cells. The optical transmission spectra show no sign of separated 135-CIGS layer. The maximum Voc of 670 mV is obtained from 5-10 nm thick 135-CIGS capping layer on 112-CIGS compared to 646 mV of only 112-CIGS. The power conversion efficiencies of the devices covered with 135-CIGS with thickness less than 80 nm are slightly lower than that of the uncovered 112-CIGS solar cells due to lower generated photocurrents. The solar cell parameters become dramatically deteriorate with thicker 135-CIGS capping layer. The XRD also shows the shift of diffraction peak toward larger 2-theta without peak broadening or splitting when the thickness of 135-CIGS is increased. The external quantum efficiency (EQE) measurements indicate the shift of absorption threshold towards shorter wavelength when the thickness of 135-CIGS is increased that is consistent with the optical transmission measurements. The photoluminescence (PL) spectra of 135-CIGS/112-CIGS heterostructure with various thicknesses of 135-CIGS layer are identified as donor-to-acceptor pairs (DAPs) and free (conduction band) -to-bound (acceptor) transitions and show the temperature and excitation power dependence on the PL spectra. On the contrary, when the thin 112-CIGS layer is deposited on top of 135-CIGS (112-CIGS/135-CIGS), the PL spectra show more pronounced and resolved peaks which are surprisingly independent of temperature and excitation power because of the interference effect. The thin 135-CIGS (1-200 nm) capping layer on the 1.8 micron 112-CIGS films show the nature of p-type, while the thin 112-CIGS (5-300 nm) capping layer on the 1.8 micron 135-CIGS films exhibit the nature of n-type.
Effect of local rewiring in adaptive epidemic ERDOS-RENYI random networks
Authors:   , Piankoranee Suwakan
Published: September 2023

Adaptive epidemic network is driven by two main processes, (1) infectionrecovery process that changes the states of the nodes, and (2) rewiring process that modifies the topology of the network. In the past two decades, epidemic models on adaptive networks have gained interests because understanding the dynamics between these two processes can be key to improving control of diseases. However, in most of these models, the rewiring mechanism is based on information known globally, i.e., everyone knows the health status of all others in the network. This concept is not practical in real life for large network. This dissertation aims to provide a more realistic rewiring model for epidemic-control strategy. We propose a method where the decision of an individual is based on its local information. We call the original rewiring method global rewiring and ours local rewiring. In this dissertation, we investigate a susceptible-infected-susceptible (SIS) epidemic model on adaptive networks for global and local rewirings. Here we find that local rewiring networks have less chance to prevent disease spreading than global rewiring networks because of limited local information. However, using kinetic Monte Carlo simulations, our results show that there are phase overlaps between both rewiring methods. This means that under a certain circumstance, even with limited local information, we can predict outcomes of an epidemic for systematic interventions.
Thermomechanical behavior and chemical sensing cationic poly(diallyldimethylammonium chloride) and anionic poly(sodium 4-styrene sulfonate) assembled into composite polyelectrolyte multilayer thin films and complex membranes
Authors:   , Saikaew Rateeya
Published: September 2023

Polyelectrolyte composite membranes of cationic PDADMAC and anionic PSS assembled into polyelectrolyte multilayer (PEM) thin film and polyelectrolyte complex (PEC) membranes were used as matrix embedded with several additive molecules. Nano-scale PEM films fabricated using the layer-by-layer deposition method and the loading and release of a hydrophobic model drug curcumin (Cur) was studied for drug delivery and sensing applications. Interestingly, it was found that the loading and release of Cur could be triggered by solvent composition and temperature. In a parallel study, the alternative to the nanoscale PEM was studied in the form of PEC, which were used as stand-alone film with a thickness in micro-scale. PECs prepared by solution-mixing using NaCl as a plasticizer followed by centrifugation and compression molding were investigated. Remarkably, not only the tuning of [NaCl] used during mixing could affect the thermomechanical behavior of salt-free films but also the changes in polyelectrolytes stoichiometry. Cur blended into non-stoichiometric PEC membranes were tested as optical NH3 vapor sensor and it was found that the excess positive stoichiometry gave the best results. To further improve the mechanical properties of both the free-standing PEM and PEC films, cellulose nanocrystals (CNCs) were used as fillers to reinforce the polymer matrix.
Novel (Cu-Sn) AND (Ni-Sn) catalysts prepared by mechanical alloying
Authors:   , Pithakratanayothin Sakollapath
Published: September 2023

This research was aimed to synthesize intermetallic catalysts using mechanical alloying (Ma) technique. Copper (Cu) and nickel (Ni) were chosen to study since not only their properties are closed to the noble metal properties, e.g. platinum and palladium, but also they are not expensive. However, as also found in noble metals, both Cu and Ni metals are oxidized easily in air. To overcome this problem, either Cu or Ni was mixed with tin (Sn) to obtain bimetallics, viz. CuSn or NiSn, respectively. Therefore, this research was focused on finding the optimal conditions to synthesize both CuSn and NiSn bimetallics using the Ma technique and studied their catalytic activity on phenol hydroxylation and hydrogenation of cinnamaldehyde, as well. Structural characterization was carried out using various instrumental techniques.
Light responsive with metallo-, and hydrogen bonded benzoxazine dimer-based supramolecular structure
Authors:   , Niyomsin Sorapat
Published: September 2023

The present work focuses on multi-responsive molecule based on supramolecular chemistry of benzoxazine dimer as a benzoxazine supramolecular crosslinker, fluorescent labelling benzoxazine conjugated with rotaxane system and benzoxazine pendant group block copolymer. The use of azobenzene derivatives in benzoxazine synthesis provides light responsive behaviour. The remained hydroxyl group from aminoalcohol allows benzoxazine to conjugate with desired functional group. The dihydroxyl benzoxazine acts as molecular crosslinker for poly(acrylic acid) by conjugation. The ring-opening reaction brings benzoxazine dimeric unit on the crosslinker which also showed metal ion complexation. The complexation strengthens the cross-linked polymer network. The complex can reversely form by treating with EDTA and CuCl₂ solution in cycle. The use of fluorescent phenol in the ring opening also brings fluorescent property. The conjugation of light responsive benzoxazine with rotaxane system followed with ring opening reaction using fluorescent phenol allows us to detect the shuttling of rotaxane. Moreover, the metal ion complexation and cis/trans isomerization were also detected by fluorescent property. The benzoxazine side group polymer can be obtained from conjugation of light responsive benzoxazine with acrylate derivatives. The polymerization with ATRP provides block copolymer. The UV light exposure and metal ion complexation affects morphology of the block copolymer.
Simulation of water effect on biodiesel production using waste cooking oil via ester-transesterification in a reactive distillation column
Authors:   , Anantapinitwatna Ajala
Published: September 2023

This research investigated the effect of water content in waste cooking oil (WCO) on the performance of a reactive distillation column for biodiesel production via ester-transesterification. A mixture of triolein and oleic acid was used as a WCO model compound. Amberlyst-15 was used to catalyze esterification while CaO was used for transesterification. From Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model taking into account water absorption for esterification of oleic acid (FFA), biodiesel yield was decreased with increasing of water content in WCO feedstocks.  On the other hand, the initial rate of transesterification was increased with increase of amount of water in WCO feedstocks in the range of 0-5%wt. However, when biodiesel yield reached the maximum value of 30-40%, saponification as a side reaction became significant and the emulsion phase of feedstocks was present, resulting in significant decrease in biodiesel yield. Therefore, the water contaminated in feedstocks should be avoided because of the presence of saponification even when using heterogeneous CaO catalyst for biodiesel production. Interestingly, hybridized reactive distillation can handle the feedstocks with the presence of water in the range of 0-8%wt commonly found in most WCO sources. It was found that the water was vaporized to the top of the column and did not flow down to the transesterification section. The hybridized reactive distillation can produce 97% biodiesel yield with 96.5% biodiesel purity according to EN14214 standard with the use of total stages of 26, reflux ratio of 0.1 and reboiler duty of 50-128 kW for the WCO feed of 1 kmol/h
Patterns of Use in Alcohol Drinking and Betel Nuts Chewing among Workers of Myitnge Train Carriage and Wagons Workshop, Myanmar
Authors:   , Aung Htet
Published: September 2023

Background: Alcohol drinking is a major concern and cause of morbidity and mortality all over the world. Historically, alcohol is still holding an important role in social interaction, relationship and bonding. Excessive amount of alcohol drinking is leading to more than 200 diseases and injury conditions including alcohol dependence, liver cirrhosis, cancers and injuries. Betel nut has been used widely throughout the history and deeply cultivated in some religious and some sociocultural events. Although betel nut chewing is not a problem for worldwide but still affects the Asia and Pacific regions such as Myanmar, Sri Lanka, India, Cambodia and Papua New Guinea. Betel nuts are defined and classified as carcinogen by World Health Organization (WHO). In Myanmar, there are still a lot of people who have both alcohol drinking and betel nuts chewing habits. In addition, people who have betel nuts chewing habits tend to drink alcohol too. Objective: This study identified the patterns of alcohol drinking and betel nuts chewing among workers of Myitnge Train Carriage and Wagons Workshop. Methods: This was a cross-sectional study with representative sample of 320 workers selected from Myitnge Train Carriage and Wagons Workshop which is located in Mandalay. The researcher team conducted the study by face to face interview. Results: The mean age of the participants was 37.97± 10.42 years. The average age of the both alcohol drinking and betel nuts chewing onset was 25 years old. Almost all of the participants (98.1%) in this study have drunk beer. There were 80 participants (25%) who were binge-drinking in this study. Most participants drank alcohol at restaurants and bars. “Ninety Two”, which is one of the betel nuts type, have highest percentage among all betel nuts types with 208 participants (65%) have been consuming. There were 76 participants who chewed 5 packs and more betel buts in the past 12 months. They chewed betel nuts mostly at work and home. There were 121 participants who like to drink alcohol after they finished chewing betel nuts and 76 participants who like to chew after they have drunk alcohol. Conclusion: All the participants have both alcohol drinking and betel nuts chewing habits. Beer was the most popular alcohol beverages and one fourth of the participants in this study were binge drinking in this study. “92” was the most popular type of betel nuts among workers. Moreover, there were almost one fourth of the participants who were chewing 5 or more than 5 packs of betel nuts in this study. Those consumptions lead to the risk of health problem. Education programs for both alcohol drinking and betel nuts chewing habits should be done for participants who drink alcohol and chew betel nuts a lot in this study. In addition, studies about patterns of alcohol drinking and betel nuts chewing should be conducted more in workers in Myanmar since there are only a few studies about them.
Prevalence and factors associated with safe sex behaviors among adolescent vocational students in Nakhon Ratchasima Province, Thailand
Authors:   , Chaumaroeng Maneebongkot
Published: September 2023

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 16.80 years (±1.7). Approximately 60.% of male and 50% of female had experience of sexual intercourse , with their first experience of sexual intercourse at the average age of 15 years old. Most respondents 63.1 % used a condom and 63.6% used contraception in their latest sexual intercourse. About 41.9% consumed alcohol and 15% was due to substance abused. Sexual intercourse among adolescents vocational students  were significantly associated with knowledge of contraception  (OR = 0.298, 95%CI= 0.47 -0.57), Positive attitude towards reproductive health (OR=0.165,95%CI= 3.32-6.71), with low risk behavior (OR = 0.45, 95%CI= 0.219-0.911), and high risk behaviors (OR = 0.24, 95%CI= 0.09-0.58). Contraceptive used in the latest sexual intercourse was significant association with cues to action (OR=0.43, 95%CI= 0.22-0.86)

 Conclusion: The study highlights the situation of safe sex behaviors among adolescent vocational students  in Nakhon Ratchasima. It is recommended that sex education should be improved within the curriculum and active campaigning in schools should be promoted.
Sexual risk behaviors and sexual harassment among female beer promoters in Chiang Mai Province, Thailand
Authors:   , Phaiyarom Mathudara
Published: September 2023

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 variables. Cross-sectional survey was conducted from May to July, 2018. Snowball sample of 184 Thai female beer promoters who were 18 years old or more were asked to complete administrative questionnaire which included demographic data, sexual activities, sexual orientation, attitudes, sexual behaviors, and sexual harassment during working as a beer promoter. Descriptive statistics and bivariate analysis were used to examine responses of participants and association between variables. The results showed that mean age of respondents was 22.73. 58.7% of them were also student and studying in bachelor degree. There were 62.5% of having sex experience with 25.2% of them did not use the condom. For sexual harassment, most of respondents had experiences in medium level especially verbal harassment. It associated with currently student status (p-value = 0.038), having sexual intercourse experience (p-value = 0.024), and type of job (p-value = 0.000). In conclusion, sexual risk behaviors were still found among female beer promoters and the occurrence of sexual harassment remained high. There were association between currently student status, having sexual intercourse experience, and type of job and sexual harassment. The findings highlighted that magnitude of sexual risk behaviors and sexual harassment should be revealed to the public. It is necessary to help people in the society consider about these issues. And campaigns for women empowerment regarding negotiation and life skills for beer promoters should be created. The further study should expand the survey to other area and mixed method is recommended to explain in-depth information.