排序方式: 共有21条查询结果,搜索用时 11 毫秒
1.
Kittisak Jantanasakulwong Sarinthip Thanakkasaranee Phisit Seesuriyachan Pisith Singjai Aphisit Saenjaiban Siriphan Photphroet Kanticha Pratinthong Yuthana Phimolsiripol Noppol Leksawasdi Thanongsak Chaiyaso Sarana Rose Sommano Pensak Jantrawut Siriwadee Chomdej Suwit Chotinan Francisco J. Barba Joe M. Regenstein Alissara Reungsang Pornchai Rachtanapun 《International journal of molecular sciences》2022,23(18)
The nano-metal-treated PET films with anti-virus and anti-fogging ability were developed using sparking nano-metal particles of Ag, Zn, and Ti wires on polyethylene terephthalate (PET) films. Ag nanoparticles were detected on the PET surface, while a continuous aggregate morphology was observed with Zn and Ti sparking. The color of the Ag-PET films changed to brown with increasing repeat sparking times, but not with the Zn-PET and Ti-PET films. The water contact angle of the nano-metal-treated PET films decreased with increasing repeat sparking times. The RT-PCR anti-virus test confirmed the high anti-virus efficiency of the nano-metal-treated PET films due to the fine particle distribution, high polarity, and binding of the nano-metal ions to the coronavirus, which was destroyed by heat after UV irradiation. A highly transparent, anti-fogging, and anti-virus face shield was prepared using the Zn-PET film. Sparking was an effective technique to prepare the alternative anti-virus and anti-fogging films for medical biomaterial applications because of their low cost, convenience, and fast processing. 相似文献
2.
Mimosa pigra peel was sun‐dried for 2 days and then ground before being boiled with 30%w/v sodium hydroxide (NaOH) at 100°C for 3 h, washed and then dried at 55°C to constant weight. The cellulose was then synthesized using different NaOH concentrations and monochloroacetic acid (MCA) in isopropyl alcohol (IPA). Effects of various NaOH concentrations on degree of substitution (DS), viscosity and thermal of carboxymethyl cellulose from Mimosa pigra peel (CMCm) were investigated. The increasing of NaOH concentration resulted in increasing DS and viscosity. However, viscosity of CMCm decreased as temperature increased. Thermal properties were studied using differential scanning calorimetry (DSC). The melting point of the samples decreased as %NaOH increased. The effects of various NaOH concentrations in CMCm synthesis on the mechanical properties and water vapor permeability (WVP) of the CMCm films were investigated as well. With increasing NaOH concentrations (30–50%) were also found to result in improved mechanical properties. However, when the level of NaOH concentration was 60%, the mechanical properties of the CMC films decreased. This result indicates that the highest mechanical properties were found for 50% NaOH‐synthesized CMCm films. The WVP of the CMCm films increased as %NaOH increased. In addition, the CMCm films were tested to determine the effect of glycerol as a plasticizer on the mechanical properties. Increasing the amount of glycerol showed an increase in elongation at break but also led to a decrease in tensile strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
3.
Pornchai Rachtanapun Susan E. M. Selke Laurent M. Matuana 《Polymer Engineering and Science》2004,44(8):1551-1560
Polymer blends, such as those resulting from recycling postconsumer plastics, often have poor mechanical properties. Microcellular foams have been shown to have the potential to improve properties, and permit higher‐value uses of mixed polymer streams. In this study, the effects of microcellular batch processing conditions (foaming time and temperature) and HDPE/PP blend compositions on the cell morphology (the average cell size and cell‐population density) and impact strength were studied. Optical microscopy was used to investigate the miscibility and crystalline morphology of the HDPE/PP blends. Pure HDPE and PP did not foam well at any processing conditions. Blending facilitated the formation of microcellular structures in polyolefins because of the poorly bonded interfaces of immiscible HDPE/PP blends, which favored cell nucleation. The experimental results indicated that well‐developed microcellular structures are produced in HDPE/PP blends at ratios of 50:50 and 30:70. The cell morphology had a strong relationship with the impact strength of foamed samples. Improvement in impact strength was associated with well‐developed microcellular morphology. Polym. Eng. Sci. 44:1551–1560, 2004. © 2004 Society of Plastics Engineers. 相似文献
4.
A model cationic reactive dye based on an anthraquinone chromophore was prepared. The synthesis of this dye was achieved by the modification of the a free amino group of an anthraquinone-based dye, reacting first with cyanuric chloride and then with N -(2-aminoethyl)pyridinium chloride. TLC analysis was employed to follow the chemical reactions. The application of the prepared dye to cotton fabric was carried out using the exhaustion method without the addition of electrolytes. The results showed that, despite no electrolytes being present in the dye bath, a high percentage of dye exhaustion could be obtained. The high percentage of dye exhaustion was attributed to the attractive force between positive charges on the dye molecule and the negatively charged fibre surface. A high degree of dye fixation with excellent wash fastness was also achievable. Advantageously, it was found that this cationic reactive dye showed promising fastness to light when compared with that of analogous conventional basic dye on cotton. It is believed that the pyridinium cationic moiety, which attached separately to the chromophore via aliphatic spacer groups, was later eliminated during the washing-off process, hence causing an insignificant effect on the photofading of the dyed fabric. 相似文献
5.
Facile fabrication of polyethylene/silver nanoparticle nanocomposites with silver nanoparticles traps and holds early antibacterial effect 下载免费PDF全文
Dau Hung Anh Kanchana Dumri Nguyen Tuan Anh Winita Punyodom Pornchai Rachtanapun 《应用聚合物科学杂志》2016,133(17)
Antibacterial polyethylene (PE)/silver nanoparticle (AgNP) nanocomposites containing AgNPs at concentrations of 5 × 10?5, 5 × 10?4, and 5 × 10?3 wt % were fabricated and tested. Transmission electron microscopy revealed an even dispersion of surface AgNPs in the PE/AgNP nanocomposites. No AgNP agglomeration was observed. The tensile strength, elongation at break, and Young's modulus of these PE/AgNP nanocomposites were similar to those of neat PE. Differential scanning calorimetry demonstrated that the PE/AgNP nanocomposites and neat PE had similar melting and crystallization temperatures of 126 ± 0.5 and 109 ± 0.6°C, respectively. The heats of fusion of the PE/AgNP nanocomposites containing AgNPs at concentrations of 5 × 10?5 and 5 × 10?4 and of 5 × 10?3 wt % were lower than those of neat PE by 5 and 7%, respectively. These PE/AgNP nanocomposites were immersed in shaking liquid cultures of the potential pathogenic bacteria Escherichia coli, Bacillus subtilis, and Salmonella typhimurium in the lag phase. The results show that the growth rates of all of the tested bacteria were restricted effectively after 1.5, 3, and 6 h of cultivation, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43331. 相似文献
6.
Pornchai Bumroongsri Soorathep Kheawhom 《International Journal of Control, Automation and Systems》2017,15(4):1479-1484
This paper focuses on the problem of robustly stabilizing uncertain discrete-time systems subject to bounded disturbances. The proposed tube-based model predictive controller ensures that all possible realizations of the state trajectory lie in the time-varying tubes so robust stability and satisfaction of the state and input constraints are guaranteed. The time-varying tubes are computed off-line so the on-line computational time is tractable. At each sampling time, the precomputed time-varying tubes are included in the optimal control problem as the constraints in the prediction horizon and only a quadratic programming problem is solved. In comparison to the algorithm that calculates the time-varying tubes on-line, the proposed algorithm can achieve the same level of control performance while the on-line computational time is greatly reduced. 相似文献
7.
Boonchoat Paosawatyanyong Pornchai Luyaphand Ketthip Anuwareephong Worawan Bhanthumnavin 《稀有金属材料与工程》2012,(Z1):64-68
The work described herein represents an efficient method in the deposition of poly(3-methylthiophene),P3MeTh,thin films utilizing a microwave plasma system in combination with a simultaneous doping with iodine.It was envisaged that,an alternative poly(3-methylthiophene),P(3MeTh),with an electron donating methyl substituent,would reduce the degree of ring opening which reportedly occur to a certain extent during the plasma polymerization process of its parent compound polythiophene.An alkyl substituent would also increase the solubility of the materials.P(3MeTh)thin film deposition has been performed utilizing microwave-induced plasma polymerization in order to directly grow films on glass substrates.Moreover,simultaneous doping of the so-formed polymer with iodine has been carried out as opposed to the post-synthesis doping method.This is aimed to prolong electrical conducting lifetime of the materials.The synthesized films were characterized by attenuated total reflection fourier transform infrared(ATR FT-IR)spectroscopy and energy dispersive X-ray spectroscopy(EDS)to confirm the incorporation of iodine dopant into the films.Scanning electron microscopy showed uniformly deposited films.It has been observed that the electrical conductivity of the doped film is 2 orders of magnitude higher than the undoped counterpart.The doped fabricated films exhibited UV-vis spectra indicative of increased π-conjugation(536 nm).Furthermore,electrical conductivity of the in situ doped P(3MeTh)is more highly sustained over a longer period of time. 相似文献
8.
In this paper, a novel synthesis approach for tube-based robust MPC is proposed. A novel feature is the fact that the proposed tube-based robust MPC algorithm can deal with both time-varying parameter and bounded disturbance. The proposed control law is the linear combination of two components. The first component steers the state of the nominal linear time-varying system to the origin. The second component keeps the state at each time step of the linear time-varying system with bounded disturbance within a tube whose center is the state of the nominal linear time-varying system. Finally, the state of the linear time-varying system with bounded disturbance is kept within a tube whose center is at the origin so robust stability is guaranteed. Satisfaction of the state and control constraints is ensured by employing tighter constraint sets for the nominal linear time-varying system. The computational burdens are the same as those in the case of the nominal linear time-varying system. 相似文献
9.
Pranee Lertsutthiwong Pornchai Rojsitthisak Ubonthip Nimmannit 《Materials science & engineering. C, Materials for biological applications》2009,29(3):856-860
Preparation of chitosan-alginate nanocapsules containing turmeric oil was carried out by emulsification of turmeric oil in aqueous sodium alginate solution and gelification with calcium chloride and chitosan, followed by solvent removal. The process parameters were optimized by variation of the molecular weight of chitosan, the chitosan/alginate mass ratio, and the order of addition of calcium chloride and chitosan in the formulation. The nanocapsules were characterized based on average size, zeta potential, morphology, percent recovery, loading capacity of turmeric oil, nanocapsule yield, and stability at 4 °C and 25 °C. The characteristics of the nanocapsules were dependent on the molecular weight and amount of chitosan. Chitosan with a low molecular weight was required to produce small nanocapsules. At a fixed chitosan/alginate mass ratio of 0.1:1, addition of chitosan after calcium chloride was found to be optimal for improving the physical stability, percent recovery of turmeric oil and nanocapsule yield, while maintaining the loading capacity of the turmeric oil. 相似文献
10.
Pornchai Kaewsapsak Onyinyechi Esonu Prof. Danielle H. Dube 《Chembiochem : a European journal of chemical biology》2013,14(6):721-726
Due to the increased prevalence of bacterial strains that are resistant to existing antibiotics, there is an urgent need for new antibacterial strategies. Bacterial glycans are an attractive target for new treatments, as they are frequently linked to pathogenesis and contain distinctive structures that are absent in humans. We set out to develop a novel targeting strategy based on surface glycans present on the gastric pathogen Helicobacter pylori (Hp). In this study, metabolic labeling of bacterial glycans with an azide‐containing sugar allowed selective delivery of immune stimulants to azide‐covered Hp. We established that Hp's surface glycans are labeled by treatment with the metabolic substrate peracetylated N‐azidoacetylglucosamine (Ac4GlcNAz). By contrast, mammalian cells treated with Ac4GlcNAz exhibited no incorporation of the chemical label within extracellular glycans. We further demonstrated that the Staudinger ligation between azides and phosphines proceeds under acidic conditions with only a small loss of efficiency. We then targeted azide‐covered Hp with phosphines conjugated to the immune stimulant 2,4‐dinitrophenyl (DNP), a compound capable of directing a host immune response against these cells. Finally, we report that immune effector cells catalyze selective damage in vitro to DNP‐covered Hp in the presence of anti‐DNP antibodies. The technology reported herein represents a novel strategy to target Hp based on its glycans. 相似文献