The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic spe...The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years.展开更多
Natural rubber(NR)foams are widely used.However,further studies are required for preparing eco-friendly NR foam and determining the optimum physical properties appropriate for application.This study aims to create an ...Natural rubber(NR)foams are widely used.However,further studies are required for preparing eco-friendly NR foam and determining the optimum physical properties appropriate for application.This study aims to create an NR foam from rubber reinforced with sugarcane bagasse ash(SCBA)and sodium alginate.The results showed that the SCBA was primarily composed of silica or silicon dioxide(87.52%by weight)and carbon(11.41%by weight).This study investigated the influence of the amount of sodium alginate(0-5 phr)used in the NR foam formation.The addition of SCBA on the NR foam affected the density,swelling behavior,and crosslink density of the foam.The results identified an optimal loading level that improved the density and morphology of the foam.The hardness and modulus of the NR foam increased with increasing amounts of SCBA,suggesting insufficient reinforcement.The NR exhibited the highest compressive stress at the SCBA concentration of 5 phr.This study facilitates the development of NR as green material and other support materials.展开更多
Plasma electrolytic oxidation(PEO)processing of light metals has been established for decades and is in increasing industrial use,even as an alternative surface treatment to produce multifunctional coatings with envir...Plasma electrolytic oxidation(PEO)processing of light metals has been established for decades and is in increasing industrial use,even as an alternative surface treatment to produce multifunctional coatings with environmental-friendly processing concept.One of the benefits of PEO processing claimed already a couple of years ago was the ability to treat dissimilar metal joints,which can obviously improve the surface homogeneity and stability at the interface of the dissimilar components,especially impeding the galvanic corrosion due to the different electrochemical properties of each component.However,the progress and breakthrough develop slowly especially for the macro scales due to the much larger gap between each component.This literature review firstly demonstrates the still low number of studies reporting successful PEO treatment of material combination such as Mg/Al,Mg/Ti,Al/Ti and scarcely light metal combinations with steel.The main issues and challenges to performing PEO processing on the macroscale dissimilar weldments were stated.On the other hand,dissimilar metal joints also widely exist in micrometer scale in alloys and metal matrix composites(MMCs).Moreover,there is a huge knowledge base on PEO treatment of such multiphase substrates.PEO processing of such complicated mixed microstructures is reviewed as well to reveal the basic problems.To some certain degree,these PEO-related studies on alloys and MMCs can be good examples to have an insight into the coating formation mechanism on macro-scaled dissimilar metal joints.Conclusions are drawn from the micro-to macroscale.Finally,critical access to the problems is given and possible solutions and reaming limitations are discussed.展开更多
This study investigates the effectiveness of salicylate(SAL)as an electrolyte additive on the discharge behavior of high-purity(HP)Mg anode in an aqueous half-cell system,using an integrated approach of mathematical m...This study investigates the effectiveness of salicylate(SAL)as an electrolyte additive on the discharge behavior of high-purity(HP)Mg anode in an aqueous half-cell system,using an integrated approach of mathematical modeling and experimental analysis.A finite elementbased model is developed to elucidate the key mechanisms by which SAL influences the voltage profile and pH.Systematic electrochemical measurements,especially intermittent discharge tests combined with electrochemical impedance spectroscopy(EIS),demonstrate that SAL can enhance initial voltage stability of HP Mg anode.Moreover,the model incorporates the SAL-Mg complexation factor to describe the role of SAL in modifying the deposit film on HP Mg surface.The agreement between model predictions and experimental observations suggests that SAL facilitates the formation of compact Mg(OH)_(2) deposits and sustains a favorable pH environment within the half-cell compartment.This integrated approach provides new insights into understanding and optimizing additive effects for Mg-air batteries.展开更多
In this review research,the full bio-medical potential and application of the severe acute respiratory syndrome(SARS)-CoV-2 viruses are discussed in detail with the aim of discovering innovative treatment strategies i...In this review research,the full bio-medical potential and application of the severe acute respiratory syndrome(SARS)-CoV-2 viruses are discussed in detail with the aim of discovering innovative treatment strategies in virology and medicine.The SARS-CoV-2 which caused an international health crisis also unraveled an opportunity to gain from its pathogenic effects to treat the affected people.The study aims at testing whether the newly discovered SARS-CoV-2 can be used for therapeutic and clinical purposes.With in-depth analytics,this investigation issue endeavors to unearth new ways of fighting infectious diseases and to improve existing medical interventions.Beside scientific and practical significance the role of this work is vital.By learning the biologic and molecular mysteries of SARS-CoV-2,the researchers can create precise medicines and vaccines not only against COVID-19 but also the other infectious diseases as well.Furthermore,this recommendation may open the door to the future development of gene therapy and vaccine technology.In this sense,it combines multiple approaches,such as viral studies,immunology,and molecular biology.Laboratory experiments,computer program modeling and clinical trials are applied to detection of the SARS-COV-2 in therapeutic implementation.The principal conclusion and analysis of this research put forth the fact that SARS-CoV-2 can be utilized in anti-viral treatment,cancer therapy,and vaccine programs.The study results confirm the inherent adaptability of viruses like SARS-CoV-2 and emphasis on the development of specific therapeutic measures.It is valuable because of its potential to add to virology and medication,showing new ways for virus-based treatment.In addition,the impact of these results on treatments would be revolutionary,with potential to invent superior and flexible interventions against infectious disease.In short,the therapeutic use of SARS-CoV-2 can be regarded as a bold innovation with tremendous consequences for general health,and ultimately for medical science.展开更多
This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsi...This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.展开更多
Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has...Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.展开更多
ZnO nanostructure materials doped with different La contents were synthesized by sonochemical method. The products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM),transmission elect...ZnO nanostructure materials doped with different La contents were synthesized by sonochemical method. The products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM),transmission electron microscopy(TEM), Raman spectroscopy, and Fourier transform infrared spectroscopy(FTIR). In this research, XRD patterns of pure ZnO and La-doped ZnO are specified as hexagonal wurtzite ZnO structure with no detection of La2O3 phase. SEM and TEM characterization revealed the flower shape of pure ZnO built-up from petals of hexagonal prisms with hexagonal pyramid tips. Upon doping with La, the flower-shaped ZnO is broken into individual 1D prism-like nanorods. Photocatalytic activities of the as-synthesized products were determined by measuring the degradation of methylene blue(MB) under ultraviolet–visible(UV) light irradiation.Among them, the 2.0 mol% La-doped ZnO shows better photocatalytic properties than any other products.展开更多
The curd of Romanesco broccoli was carbonized at 900°C under argon atmosphere in a gold furnace chamber. The carbonization afforded a carbon material with a fine logarithmic spiral on the surface, resembling t...The curd of Romanesco broccoli was carbonized at 900°C under argon atmosphere in a gold furnace chamber. The carbonization afforded a carbon material with a fine logarithmic spiral on the surface, resembling the Fibonacci parastichy structure of the Romanesco broccoli flower bud. The carbonized “flower bud” structure was observed under scanning electron microscopy. Infrared absorption spectra and X-ray photoelectron spectroscopy measurements confirmed the chemical structure and component of the carbon material.展开更多
In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were system...In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.展开更多
The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries.The respective voltage loss is typically assigned to the de...The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries.The respective voltage loss is typically assigned to the deposits layer forming on the anode surface during discharge.In this work,we experimentally and computationally investigate the critical factors affecting the voltage drop at Mg anode towards a deeper understanding of the contribution of deposit and its growth.A two-dimensional(2D)mathematical model is proposed to compute the voltage drop of Mg-0.15Ca wt.%alloy(Mg-0.15Ca)by means of a semi-empirical formulas and experiments-based modification model,considering the effect of discharge current density,the negative difference effect(NDE)and surface deposits layer itself.This model is utilized to simulate the discharge potential of the anode at predefined experimental current densities.The computed voltage drop(half-cell voltage)is in good agreement with the experimental value.The applicability of the mathematical model is successfully validated on the second material(namely high-purity Mg).展开更多
Crosslinking natural rubber (NR) and styrene butadiene rubber (SBR) composites with carbon black (CB) have been utilized in the tire tread industry.A sulfur-based lightly crosslinker can potentially enhance the self-h...Crosslinking natural rubber (NR) and styrene butadiene rubber (SBR) composites with carbon black (CB) have been utilized in the tire tread industry.A sulfur-based lightly crosslinker can potentially enhance the self-healing capabilities of rubber.Moreover,the rubber composites were studied for non-covalent interactions between the benzene rings of SBR and CB.In this research,rubber samples were prepared,and their structure was investigated using Fourier transform infrared (FTIR),and Raman spectroscopy.The red shift in Raman spectroscopy confirmed noncovalent interaction or hydrophobic interaction between SBR and CB in NR/SBR composites exposed to CB due to environmental change.The differential scanning calorimetry (DSC) thermograms showed that NR and SBR were incompatible.Additionally,the mechanical properties of these rubber blends were enhanced as the proportion of NR increased.The maximum self-healing performance reached 40%for the formulation containing 25 phr NR and 75 phr SBR,which also saved energy with low chain end movements.Therefore,these composites could be utilized as a semi-empirical model for studying crosslinked rubber blends,specifically in the rubber tire industry.展开更多
With the growing demand for weight reduction,the application of joint lightweight structural materials is increasing.Magnesium alloys feature low density,high specific strength and good formability,offering significan...With the growing demand for weight reduction,the application of joint lightweight structural materials is increasing.Magnesium alloys feature low density,high specific strength and good formability,offering significant advantages for fuel efficiency and load capacity.Combined with Ti,a dissimilar Ti/Mg composite material provides great flexibility combining the properties of each material.However,because of the great differences in chemical and electrochemical properties between Mg and Ti,it is imperative to address the galvanic corrosion problem of such dissimilar Ti/Mg components.This work presents an investigation of the PEO processing of sintered Ti/Mg0.6Ca couples,aiming to improve the corrosion resistance of such dissimilar alloy combinations using a phosphate-aluminate electrolyte.The results show that uniform and continuous coatings can be formed on the dissimilar Ti/Mg0.6Ca couple.The coating mainly contains MgO and MgAl_(2)O_(4)on the Mg0.6Ca side,and Al_(2)TiO_(5)is the dominant phase on the Ti side.The work also took advantage of synchrotron X-ray computed tomography(CT)scanning to achieve 3D reconstruction of the coating morphology,which can be a fast method to assess the porosity and compactness of the coating and further predict the coating corrosion resistance.The coating effectively improved the corrosion resistance of the dissimilar Ti/Mg0.6Ca couple.展开更多
The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending o...The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending on the length of the blocks.In our study,we experimented with different types and systematically investigated the variation of the critical micelle concentration(CMC)of poloxamers at 25 and 37°C in different media.In addition,the cytotoxicity of the different poloxamer micelles on three different cell lines was evaluated,and based on the results,Plur104,Plur123,and Plur127 were selected.Fatty acid elongated derivatives of a short antibacterial peptide(pL1),a medium-sized anticancer peptide(pCM15),and a branched-chain vaccine antigen(pATIPC)were used as lipopeptide models,and their formulations with the selected poloxamers were investigated.The solubility and homogeneity of the lipopeptides were significantly increased,and dynamic light scattering(DLS)measurements showed the formation of small particles of around 20 nm,which were well reproducible and storable.Similar homogenous micelle formation was observed after freeze-drying and reconstitution with water.The pL1 lipopeptide,formulated with the selected poloxamers,exhibited enhanced antibacterial activity with significantly reduced haemolytic side effects.The pCM15 peptide,when incorporated into poloxamer micelles,showed significantly enhanced cytotoxicity against tumor cells.Additionally,the internalization rate of poloxamer-formulated pATIPC peptide by antigen-presenting model cells exceeded that of the unformulated peptide.Our results demonstrate the potential of poloxamers as promising tools for the formulation of lipopeptides and for the optimization of their selectivity.展开更多
Recently,the use of ultrasound(US)for triggering drug release to specific tissues was explored,but its direct effects on cells have not been thoroughly understood.For this reason,this study aimed to investigate the im...Recently,the use of ultrasound(US)for triggering drug release to specific tissues was explored,but its direct effects on cells have not been thoroughly understood.For this reason,this study aimed to investigate the impact of US powers and US irradiation times on fibroblast cells(NIH‐3T3).The results showed that the diverse US settings had varying effects on cell proliferation and distribution in the polystyrene culture dish.Interestingly,at 10 W,43 kHz with changing exposed time up to 30 min either stimulated or inhibited fibroblast cell growth after 24 and 72 h of cultivation compared to the control sample in the absence of US,while longer US exposure time led to a moderate reduction in cell quantity.Moreover,higher US levels of 20 and 30 W could cause an aggregation of cells and sublethal damage to the cells.Importantly,the morphology of fibroblast was changed from stellate‐shape to round‐shape under greater US powers.Elevated US power also influenced interactions between proteins and lipids,affecting the atomic and molecular charges,leading to changes in both zeta potential and pH of the dispensed cell solution.展开更多
Creep and anelastic backflow behaviors of pure copper (4N Cu) with grain size dg=40 μm were investigated at low temperatures of T〈0.3Tm (Tm is melting point) and ultra-low creep rates of ε≤1×10^-10 s^-1 b...Creep and anelastic backflow behaviors of pure copper (4N Cu) with grain size dg=40 μm were investigated at low temperatures of T〈0.3Tm (Tm is melting point) and ultra-low creep rates of ε≤1×10^-10 s^-1 by a high strain-resolution measurement (the helicoid spring specimen technique). Analysis of creep data was based on the scaling factors of creep curves instead of the conventional extrapolated steady-state creep rate. Power-law creep equation is suggested to be the best for describing the primary transient creep behavior, because the pre-parameter does not apparently change with elapsed time. The observed anelastic strains are 1/6 of the calculated elastic strains, and linear viscous behavior was identified from the logarithm plot of the anelastic strain rate versus anelastic strain (slope equals 1). Therefore, the creep anelasticity is suggested to be due to the unbowing of there-dimensional network of dislocations.展开更多
Transient creep at very low strain rates (less than 10-10 s-1) is still unclear. The traditional uniaxial creep testing is less useful due to unsatisfied resolution strain (~10-6). To study transient creep behavio...Transient creep at very low strain rates (less than 10-10 s-1) is still unclear. The traditional uniaxial creep testing is less useful due to unsatisfied resolution strain (~10-6). To study transient creep behavior at such low strain rates, a high-resolution strain measurement using the helicoid spring specimen technique was employed in a fine-grained Al-5356 alloy at temperatures ranging from 0.47Tm to 0.74Tm (Tm: melting point). To clarify transient creep mechanism at such low strain rates, transmission electron microscopy (TEM) was used in microstructure observation of crept specimens. The abnormal transient creep, high temperature strengthening at T〉Tp (Tp: the phase transformation temperature, 0.58Tm) or intermediate temperature softening at 0.4Tm〈T£Tp and double-normal type (creep curves including double work-hardening stages) at T=Tp, were firstly observed. The substructure observation in a crept specimen at T=0.58Tm and e=1×10-4 shows pile-up dislocations including many small jogs with equal interval, and dislocations emitted from grain boundaries. The b-Al3Mg2 phase dissolves under the condition of testing temperatures higher than 523 K, which causes solid-solution quantity of Mg atoms to increase. Therefore, the “abnormal transient creep” may be related to the difference of solid solution strengthening caused by phase change during the creep tests.展开更多
Hydrophobic PEO coatings were fabricated in an electrolyte containing potassium stearate.The wetting behaviour of coated samples was studied using dynamic and static contact angle.Also,the corrosion behaviour of the s...Hydrophobic PEO coatings were fabricated in an electrolyte containing potassium stearate.The wetting behaviour of coated samples was studied using dynamic and static contact angle.Also,the corrosion behaviour of the samples was evaluated by polarization method.The dynamic contact angle and hysteresis of the contact angle for PEO coating were evaluated by Wilhelmy plate method.There was an increase in the contact angle of the nanocomposite and traditional PEO coatings when potassium stearate was added to the electrolyte up to 130°.The more hydrophobic coatings,showed more corrosion resistance in 3.5 wt.%NaCl solution.The synergistic effect of potassium stearate and nanoparticles increased the hydrophobicity because of assembling of fatty acid on ceramic powder.展开更多
基金supported by the Science Achievement Scholarship of Thailand (SAST)the support of Office of Atom for Peace,Thailand and Thailand Institute of Nuclear Technology (a public organization) for providing facilities for some experiment in this work。
文摘The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years.
基金supported by the Thailand Science Research and Innovation,National Science Research and Innovation Fund and the Fundamental Fund(FF 2023).
文摘Natural rubber(NR)foams are widely used.However,further studies are required for preparing eco-friendly NR foam and determining the optimum physical properties appropriate for application.This study aims to create an NR foam from rubber reinforced with sugarcane bagasse ash(SCBA)and sodium alginate.The results showed that the SCBA was primarily composed of silica or silicon dioxide(87.52%by weight)and carbon(11.41%by weight).This study investigated the influence of the amount of sodium alginate(0-5 phr)used in the NR foam formation.The addition of SCBA on the NR foam affected the density,swelling behavior,and crosslink density of the foam.The results identified an optimal loading level that improved the density and morphology of the foam.The hardness and modulus of the NR foam increased with increasing amounts of SCBA,suggesting insufficient reinforcement.The NR exhibited the highest compressive stress at the SCBA concentration of 5 phr.This study facilitates the development of NR as green material and other support materials.
基金the China Scholarship Council(No.201708510113)for fellowship and funding.
文摘Plasma electrolytic oxidation(PEO)processing of light metals has been established for decades and is in increasing industrial use,even as an alternative surface treatment to produce multifunctional coatings with environmental-friendly processing concept.One of the benefits of PEO processing claimed already a couple of years ago was the ability to treat dissimilar metal joints,which can obviously improve the surface homogeneity and stability at the interface of the dissimilar components,especially impeding the galvanic corrosion due to the different electrochemical properties of each component.However,the progress and breakthrough develop slowly especially for the macro scales due to the much larger gap between each component.This literature review firstly demonstrates the still low number of studies reporting successful PEO treatment of material combination such as Mg/Al,Mg/Ti,Al/Ti and scarcely light metal combinations with steel.The main issues and challenges to performing PEO processing on the macroscale dissimilar weldments were stated.On the other hand,dissimilar metal joints also widely exist in micrometer scale in alloys and metal matrix composites(MMCs).Moreover,there is a huge knowledge base on PEO treatment of such multiphase substrates.PEO processing of such complicated mixed microstructures is reviewed as well to reveal the basic problems.To some certain degree,these PEO-related studies on alloys and MMCs can be good examples to have an insight into the coating formation mechanism on macro-scaled dissimilar metal joints.Conclusions are drawn from the micro-to macroscale.Finally,critical access to the problems is given and possible solutions and reaming limitations are discussed.
基金the China Scholarship Council for the award of fellowship and funding No.201908510177 and No.202106050030supported by dtec.bw–Digitalization and Technology Research Center of the Bundeswehr which Dr.Deng gratefully acknowledges project DMF+1 种基金the AMABML project founded by the Zentrum für Hochleistungs-materialien(ZHM)DEZAIN project for financial support via grant from GIF,the German-Israeli Foundation for Scientific Research and Development.
文摘This study investigates the effectiveness of salicylate(SAL)as an electrolyte additive on the discharge behavior of high-purity(HP)Mg anode in an aqueous half-cell system,using an integrated approach of mathematical modeling and experimental analysis.A finite elementbased model is developed to elucidate the key mechanisms by which SAL influences the voltage profile and pH.Systematic electrochemical measurements,especially intermittent discharge tests combined with electrochemical impedance spectroscopy(EIS),demonstrate that SAL can enhance initial voltage stability of HP Mg anode.Moreover,the model incorporates the SAL-Mg complexation factor to describe the role of SAL in modifying the deposit film on HP Mg surface.The agreement between model predictions and experimental observations suggests that SAL facilitates the formation of compact Mg(OH)_(2) deposits and sustains a favorable pH environment within the half-cell compartment.This integrated approach provides new insights into understanding and optimizing additive effects for Mg-air batteries.
文摘In this review research,the full bio-medical potential and application of the severe acute respiratory syndrome(SARS)-CoV-2 viruses are discussed in detail with the aim of discovering innovative treatment strategies in virology and medicine.The SARS-CoV-2 which caused an international health crisis also unraveled an opportunity to gain from its pathogenic effects to treat the affected people.The study aims at testing whether the newly discovered SARS-CoV-2 can be used for therapeutic and clinical purposes.With in-depth analytics,this investigation issue endeavors to unearth new ways of fighting infectious diseases and to improve existing medical interventions.Beside scientific and practical significance the role of this work is vital.By learning the biologic and molecular mysteries of SARS-CoV-2,the researchers can create precise medicines and vaccines not only against COVID-19 but also the other infectious diseases as well.Furthermore,this recommendation may open the door to the future development of gene therapy and vaccine technology.In this sense,it combines multiple approaches,such as viral studies,immunology,and molecular biology.Laboratory experiments,computer program modeling and clinical trials are applied to detection of the SARS-COV-2 in therapeutic implementation.The principal conclusion and analysis of this research put forth the fact that SARS-CoV-2 can be utilized in anti-viral treatment,cancer therapy,and vaccine programs.The study results confirm the inherent adaptability of viruses like SARS-CoV-2 and emphasis on the development of specific therapeutic measures.It is valuable because of its potential to add to virology and medication,showing new ways for virus-based treatment.In addition,the impact of these results on treatments would be revolutionary,with potential to invent superior and flexible interventions against infectious disease.In short,the therapeutic use of SARS-CoV-2 can be regarded as a bold innovation with tremendous consequences for general health,and ultimately for medical science.
基金the Franco-Thai Cooperation Programme in Higher Education and Research(Franco-Thai Mobility Programme/PHC SIAM)Year 2024-2025。
文摘This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.
基金supported by the National Research Council of Thailand(No.NRCT-5-RSA63004-16)Chiang Mai University.S.Pakluea acknowledges scholarship support from the Science Achievement Scholarship of Thailand(SAST).
文摘Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.
基金financially supported by the National Research University Project for Chiang Mai University (CMU) from the Thailand’s Office of the Higher Education Commission, Thailand
文摘ZnO nanostructure materials doped with different La contents were synthesized by sonochemical method. The products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM),transmission electron microscopy(TEM), Raman spectroscopy, and Fourier transform infrared spectroscopy(FTIR). In this research, XRD patterns of pure ZnO and La-doped ZnO are specified as hexagonal wurtzite ZnO structure with no detection of La2O3 phase. SEM and TEM characterization revealed the flower shape of pure ZnO built-up from petals of hexagonal prisms with hexagonal pyramid tips. Upon doping with La, the flower-shaped ZnO is broken into individual 1D prism-like nanorods. Photocatalytic activities of the as-synthesized products were determined by measuring the degradation of methylene blue(MB) under ultraviolet–visible(UV) light irradiation.Among them, the 2.0 mol% La-doped ZnO shows better photocatalytic properties than any other products.
文摘The curd of Romanesco broccoli was carbonized at 900°C under argon atmosphere in a gold furnace chamber. The carbonization afforded a carbon material with a fine logarithmic spiral on the surface, resembling the Fibonacci parastichy structure of the Romanesco broccoli flower bud. The carbonized “flower bud” structure was observed under scanning electron microscopy. Infrared absorption spectra and X-ray photoelectron spectroscopy measurements confirmed the chemical structure and component of the carbon material.
基金the project of the Czech Science Foundation (No.20-19170S)the German Research Foundation (Deutsche Forschungsgemeinschaft (DFG))for financial support within the scope of project (No.SCHA 1484/46-1).
基金China Scholarship Council for the award of fellowship and funding(No.202006370022).
文摘In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.
基金the China Scholarship Council for the award of fellowship and funding No.201908510177 and No.202106050030funded by dtec.bw-Digitalization and Technology Research Center of the Bundeswehr which project DMF+1 种基金The AMABML project founded by the Zentrum für Hochleistungsmaterialien(ZHM)DEZAIN project for financial support via grant from GIF,the German-Israeli Foundation for Scientific Research and Development。
文摘The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries.The respective voltage loss is typically assigned to the deposits layer forming on the anode surface during discharge.In this work,we experimentally and computationally investigate the critical factors affecting the voltage drop at Mg anode towards a deeper understanding of the contribution of deposit and its growth.A two-dimensional(2D)mathematical model is proposed to compute the voltage drop of Mg-0.15Ca wt.%alloy(Mg-0.15Ca)by means of a semi-empirical formulas and experiments-based modification model,considering the effect of discharge current density,the negative difference effect(NDE)and surface deposits layer itself.This model is utilized to simulate the discharge potential of the anode at predefined experimental current densities.The computed voltage drop(half-cell voltage)is in good agreement with the experimental value.The applicability of the mathematical model is successfully validated on the second material(namely high-purity Mg).
基金supported by Budget Bureau, The Prime Minister’s Office, Thailand (the strategic program on value creation agriculture for Kasetsart University in the fiscal year 2024)。
文摘Crosslinking natural rubber (NR) and styrene butadiene rubber (SBR) composites with carbon black (CB) have been utilized in the tire tread industry.A sulfur-based lightly crosslinker can potentially enhance the self-healing capabilities of rubber.Moreover,the rubber composites were studied for non-covalent interactions between the benzene rings of SBR and CB.In this research,rubber samples were prepared,and their structure was investigated using Fourier transform infrared (FTIR),and Raman spectroscopy.The red shift in Raman spectroscopy confirmed noncovalent interaction or hydrophobic interaction between SBR and CB in NR/SBR composites exposed to CB due to environmental change.The differential scanning calorimetry (DSC) thermograms showed that NR and SBR were incompatible.Additionally,the mechanical properties of these rubber blends were enhanced as the proportion of NR increased.The maximum self-healing performance reached 40%for the formulation containing 25 phr NR and 75 phr SBR,which also saved energy with low chain end movements.Therefore,these composites could be utilized as a semi-empirical model for studying crosslinked rubber blends,specifically in the rubber tire industry.
基金We also thank DESY(Hamburg,Germany)for granting beamtime to the proposal I-20221296 and support of the PETRAⅢP05 end-station.
文摘With the growing demand for weight reduction,the application of joint lightweight structural materials is increasing.Magnesium alloys feature low density,high specific strength and good formability,offering significant advantages for fuel efficiency and load capacity.Combined with Ti,a dissimilar Ti/Mg composite material provides great flexibility combining the properties of each material.However,because of the great differences in chemical and electrochemical properties between Mg and Ti,it is imperative to address the galvanic corrosion problem of such dissimilar Ti/Mg components.This work presents an investigation of the PEO processing of sintered Ti/Mg0.6Ca couples,aiming to improve the corrosion resistance of such dissimilar alloy combinations using a phosphate-aluminate electrolyte.The results show that uniform and continuous coatings can be formed on the dissimilar Ti/Mg0.6Ca couple.The coating mainly contains MgO and MgAl_(2)O_(4)on the Mg0.6Ca side,and Al_(2)TiO_(5)is the dominant phase on the Ti side.The work also took advantage of synchrotron X-ray computed tomography(CT)scanning to achieve 3D reconstruction of the coating morphology,which can be a fast method to assess the porosity and compactness of the coating and further predict the coating corrosion resistance.The coating effectively improved the corrosion resistance of the dissimilar Ti/Mg0.6Ca couple.
基金support of the Lendület(Momentum)Programme of the Hungarian Academy of Sciences(Grant No.:LP2021-28)the National Research,Development and Innovation Fund of Hungary,financed under the 2018-1.2.1-NKP funding scheme(Project No.:2018-1.2.1-NKP-2018-00005)the National Research,Development and Innovation Office,NKFIH,Hungary(Grant Nos.:K131594,2020-1-1-2-PIACI-KFI_2020-00021,and TKP2021-EGA-31).
文摘The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending on the length of the blocks.In our study,we experimented with different types and systematically investigated the variation of the critical micelle concentration(CMC)of poloxamers at 25 and 37°C in different media.In addition,the cytotoxicity of the different poloxamer micelles on three different cell lines was evaluated,and based on the results,Plur104,Plur123,and Plur127 were selected.Fatty acid elongated derivatives of a short antibacterial peptide(pL1),a medium-sized anticancer peptide(pCM15),and a branched-chain vaccine antigen(pATIPC)were used as lipopeptide models,and their formulations with the selected poloxamers were investigated.The solubility and homogeneity of the lipopeptides were significantly increased,and dynamic light scattering(DLS)measurements showed the formation of small particles of around 20 nm,which were well reproducible and storable.Similar homogenous micelle formation was observed after freeze-drying and reconstitution with water.The pL1 lipopeptide,formulated with the selected poloxamers,exhibited enhanced antibacterial activity with significantly reduced haemolytic side effects.The pCM15 peptide,when incorporated into poloxamer micelles,showed significantly enhanced cytotoxicity against tumor cells.Additionally,the internalization rate of poloxamer-formulated pATIPC peptide by antigen-presenting model cells exceeded that of the unformulated peptide.Our results demonstrate the potential of poloxamers as promising tools for the formulation of lipopeptides and for the optimization of their selectivity.
基金Nagaoka University of Technology,Japan and Chulalongkorn University。
文摘Recently,the use of ultrasound(US)for triggering drug release to specific tissues was explored,but its direct effects on cells have not been thoroughly understood.For this reason,this study aimed to investigate the impact of US powers and US irradiation times on fibroblast cells(NIH‐3T3).The results showed that the diverse US settings had varying effects on cell proliferation and distribution in the polystyrene culture dish.Interestingly,at 10 W,43 kHz with changing exposed time up to 30 min either stimulated or inhibited fibroblast cell growth after 24 and 72 h of cultivation compared to the control sample in the absence of US,while longer US exposure time led to a moderate reduction in cell quantity.Moreover,higher US levels of 20 and 30 W could cause an aggregation of cells and sublethal damage to the cells.Importantly,the morphology of fibroblast was changed from stellate‐shape to round‐shape under greater US powers.Elevated US power also influenced interactions between proteins and lipids,affecting the atomic and molecular charges,leading to changes in both zeta potential and pH of the dispensed cell solution.
基金Project(12JCYBJC32100)supported by the Tianjin Research Program of Application Foundation and Advanced Technology,ChinaProject([2013]693)supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,China
文摘Creep and anelastic backflow behaviors of pure copper (4N Cu) with grain size dg=40 μm were investigated at low temperatures of T〈0.3Tm (Tm is melting point) and ultra-low creep rates of ε≤1×10^-10 s^-1 by a high strain-resolution measurement (the helicoid spring specimen technique). Analysis of creep data was based on the scaling factors of creep curves instead of the conventional extrapolated steady-state creep rate. Power-law creep equation is suggested to be the best for describing the primary transient creep behavior, because the pre-parameter does not apparently change with elapsed time. The observed anelastic strains are 1/6 of the calculated elastic strains, and linear viscous behavior was identified from the logarithm plot of the anelastic strain rate versus anelastic strain (slope equals 1). Therefore, the creep anelasticity is suggested to be due to the unbowing of there-dimensional network of dislocations.
基金Project(12JCYBJC32100)supported by Tianjin Research Program of Application Foundation and Advanced Technologyin part by Grants-in-Aid from the Japan Society for the Promotion of Science(JSPS)
文摘Transient creep at very low strain rates (less than 10-10 s-1) is still unclear. The traditional uniaxial creep testing is less useful due to unsatisfied resolution strain (~10-6). To study transient creep behavior at such low strain rates, a high-resolution strain measurement using the helicoid spring specimen technique was employed in a fine-grained Al-5356 alloy at temperatures ranging from 0.47Tm to 0.74Tm (Tm: melting point). To clarify transient creep mechanism at such low strain rates, transmission electron microscopy (TEM) was used in microstructure observation of crept specimens. The abnormal transient creep, high temperature strengthening at T〉Tp (Tp: the phase transformation temperature, 0.58Tm) or intermediate temperature softening at 0.4Tm〈T£Tp and double-normal type (creep curves including double work-hardening stages) at T=Tp, were firstly observed. The substructure observation in a crept specimen at T=0.58Tm and e=1×10-4 shows pile-up dislocations including many small jogs with equal interval, and dislocations emitted from grain boundaries. The b-Al3Mg2 phase dissolves under the condition of testing temperatures higher than 523 K, which causes solid-solution quantity of Mg atoms to increase. Therefore, the “abnormal transient creep” may be related to the difference of solid solution strengthening caused by phase change during the creep tests.
文摘Hydrophobic PEO coatings were fabricated in an electrolyte containing potassium stearate.The wetting behaviour of coated samples was studied using dynamic and static contact angle.Also,the corrosion behaviour of the samples was evaluated by polarization method.The dynamic contact angle and hysteresis of the contact angle for PEO coating were evaluated by Wilhelmy plate method.There was an increase in the contact angle of the nanocomposite and traditional PEO coatings when potassium stearate was added to the electrolyte up to 130°.The more hydrophobic coatings,showed more corrosion resistance in 3.5 wt.%NaCl solution.The synergistic effect of potassium stearate and nanoparticles increased the hydrophobicity because of assembling of fatty acid on ceramic powder.