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Measurement of very low-molecular weight metabolites by traveling wave ion mobility and its use in human urine samples
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作者 Alongkorn Kurilung Suphitcha Limjiasahapong +9 位作者 Khwanta Kaewnarin Pattipong Wisanpitayakorn Narumol Jariyasopit Kwanjeera Wanichthanarak Sitanan Sartyoungkul Stephen Choong Chee Wong Nuankanya Sathirapongsasuti Chagriya Kitiyakara Yongyut Sirivatanauksorn Sakda Khoomrung 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期733-743,共11页
The collision cross-sections(CCS)measurement using ion mobility spectrometry(IMS)in combination with mass spectrometry(MS)offers a great opportunity to increase confidence in metabolite identification.However,owing to... The collision cross-sections(CCS)measurement using ion mobility spectrometry(IMS)in combination with mass spectrometry(MS)offers a great opportunity to increase confidence in metabolite identification.However,owing to the lack of sensitivity and resolution,IMS has an analytical challenge in studying the CCS values of very low-molecular-weight metabolites(VLMs250 Da).Here,we describe an analytical method using ultrahigh-performance liquid chromatography(UPLC)coupled to a traveling wave ion mobility-quadrupole-time-of-flight mass spectrometer optimized for the measurement of VLMs in human urine samples.The experimental CCS values,along with mass spectral properties,were reported for the 174 metabolites.The experimental data included the mass-to-charge ratio(m/z),retention time(RT),tandem MS(MS/MS)spectra,and CCS values.Among the studied metabolites,263 traveling wave ion mobility spectrometry(TWIMS)-derived CCS values(TWCCSN2)were reported for the first time,and more than 70%of these were CCS values of VLMs.The TWCCSN2 values were highly repeatable,with inter-day variations of<1%relative standard deviation(RSD).The developed method revealed excellent TWCCSN2 accuracy with a CCS difference(DCCS)within±2%of the reported drift tube IMS(DTIMS)and TWIMS CCS values.The complexity of the urine matrix did not affect the precision of the method,as evidenced by DCCS within±1.92%.According to the Metabolomics Standards Initiative,55 urinary metabolites were identified with a confidence level of 1.Among these 55 metabolites,53(96%)were VLMs.The larger number of confirmed compounds found in this study was a result of the addition of TWCCSN2 values,which clearly increased metabolite identification confidence. 展开更多
关键词 Very low-molecular-weight metabolites Traveling wave ion mobility Collision cross-section Human urine
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Screen-Printable Functional Nanomaterials for Flexible and Wearable Single-Enzyme-Based Energy-Harvesting and Self-Powered Biosensing Devices
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作者 Kornautchaya Veenuttranon Kanyawee Kaewpradub Itthipon Jeerapan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期254-269,共16页
Developing flexible bioelectronics is essential to the realization of artificial intelligence devices and biomedical applications, such as wearables, but their potential is limited by sustainable energy supply. An enz... Developing flexible bioelectronics is essential to the realization of artificial intelligence devices and biomedical applications, such as wearables, but their potential is limited by sustainable energy supply. An enzymatic biofuel cell(BFC) is promising for power supply, but its use is limited by the challenges of incorporating multiple enzymes and rigid platforms. This paper shows the first example of screen-printable nanocomposite inks engineered for a single-enzyme-based energy-harvesting device and a self-powered biosensor driven by glucose on bioanode and biocathode. The anode ink is modified with naphthoquinone and multiwalled carbon nanotubes(MWCNTs), whereas the cathode ink is modified with Prussian blue/MWCNT hybrid before immobilizing with glucose oxidase. The flexible bioanode and the biocathode consume glucose. This BFC yields an open circuit voltage of 0.45 V and a maximum power density of 266 μW cm-2. The wearable device coupled with a wireless portable system can convert chemical energy into electric energy and detect glucose in artificial sweat. The self-powered sensor can detect glucose concentrations up to 10 mM. Common interfering substances,including lactate, uric acid, ascorbic acid, and creatinine, have no effect on this self-powered biosensor. Additionally, the device can endure multiple mechanical deformations. New advances in ink development and flexible platforms enable a wide range of applications, including on-body electronics, self-sustainable applications, and smart fabrics. 展开更多
关键词 Screen-printable nanocomposites GLUCOSE Glucose oxidase Biofuel cells Self-powered biosensors Flexible bioelectronics
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Efficient degradation of dye pollutants in wastewater via photocatalysis using a magnetic zinc oxide/graphene/iron oxide-based catalyst
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作者 Piyawan Nuengmatcha Arnannit Kuyyogsuy +3 位作者 Paweena Porrawatkul Rungnapa Pimsen Saksit Chanthai Prawit Nuengmatcha 《Water Science and Engineering》 EI CAS CSCD 2023年第3期243-251,共9页
In this paper, we present a proof-of-concept study of the enhancement of photocatalytic activity via a combined strategy of fabricating a visible-light responsive ternary heterostructure and improving overall photosta... In this paper, we present a proof-of-concept study of the enhancement of photocatalytic activity via a combined strategy of fabricating a visible-light responsive ternary heterostructure and improving overall photostability by incorporating magnetic zinc oxide/graphene/iron oxide (ZGF). A solvothermal approach was used to synthesize the catalyst. X-ray diffraction (XRD), scanning electron microscopic, energy dispersive X-ray, transmission electron microscopic, vibrating sample magnetometric, and ultraviolet–visible diffuse reflectance spectroscopic techniques were used to characterize the synthesized samples. The obtained optimal Zn(NO_(3))_(2) concentration, temperature, and heating duration were 0.10 mol/L, 600℃, and 1 h, respectively. The XRD pattern revealed the presence of peaks corresponding to zinc oxide, graphene, and iron oxide, indicating that the ZGF catalyst was effectively synthesized. Furthermore, when the developed ZGF was used for methylene blue dye degradation, the optimum irradiation time, dye concentration, catalyst dosage, irradiation intensity, and solution pH were 90 min, 10 mg/L, 0.03 g/L, 100 W, and 8.0, respectively. Therefore, the synthesized ZGF system could be used as a catalyst to degrade dyes in wastewater samples. This hybrid nanocomposite consisting of zinc oxide, graphene, and iron oxide could also be used as an effective photocatalytic degrader for various dye pollutants. 展开更多
关键词 Magnetic zinc oxide/graphene/iron oxide PHOTOCATALYSIS Dye pollutants CATALYST Degradation
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Novel Magnetically Interconnected Micro/Macroporous Structure of Monolithic Porous Carbon Adsorbent Derived from Sodium Alginate and Wasted Black Liquor and Its Adsorption Performance 被引量:1
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作者 Parichart Onsri Decha Dechtrirat +5 位作者 Patcharakamon Nooeaid Apiluck Eiad-ua Pongsaton Amornpitoksuk Supanna Techasakul Ahmad Taufiq Laemthong Chuenchom 《Journal of Renewable Materials》 SCIE EI 2021年第6期1059-1074,共16页
The novel and facile preparation of magnetically interconnected micro/macroporous structure of monolithic porous carbon adsorbent(MPCA)were designed and presented herein.The synthesis was achieved via conventional fre... The novel and facile preparation of magnetically interconnected micro/macroporous structure of monolithic porous carbon adsorbent(MPCA)were designed and presented herein.The synthesis was achieved via conventional freezedrying and pyrolysis processes.In this study,sodium alginate and wasted black liquor were employed as starting precursors.Sodium alginate acts as a template of materials,whereas black liquor,the wasted product from the paper industry with plentiful of lignin content and alkaline solution,played an essential role in the reinforcement and activation of porosity for the resulting materials.Moreover,both the precursors were well dissolved in Fe^(3+) solution,providing a simple addition of a magnetic source in a one-pot synthesis.The interconnected micro/macroporous structures were generated through freeze-drying and,subsequently the pyrolysis process.The obtained cylindricalshaped monolithic porous carbon adsorbent(MPCA-700)showed high mechanical stability,a high BET specific surface area(902 m^(2)/g).Such aforementioned features were considered suitable to make the synthesized monolith as an adsorbent for the removal of heavy metal ions.The maximum adsorption capacity of MPCA-700 towards Pb^(2+) ions was 76.34 mg/g at pH 5.The adsorption studies illustrated that adsorption kinetics and isotherm perfectly fitted with the pseudo-second-order kinetics model and Langmuir isotherm,respectively.This work presents a promising protocol to reduce the overall costs in the preparation of renewable adsorbents with good adsorption efficiency and regeneration. 展开更多
关键词 Hierarchical porous carbon monoliths magnetic properties adsorption ALGINATE black liquor
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Recent progress in two-dimensional metallenes and their potential application as electrocatalyst
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作者 Umer Shahzad Mohsin Saeed +7 位作者 Muhammad Fazle Rabbee Hadi M.Marwani Jehan Y.Al-Humaidi Muhammad Altaf Raed H.Althomali Kwang-Hyun Baek Md.Rabiul Awual Mohammed M.Rahman 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期577-598,共22页
In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis sectors.Catalysis is one area where their exceptional physicochemical and ele... In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis sectors.Catalysis is one area where their exceptional physicochemical and electrical characteristics might be useful.Metallenes are unique because they include several metal atoms that are not in a coordinated bond.This makes them more active and improves their atomic uti-lization,which in turn increases their catalytic potential.This article delves into the potential of two-dimensional metals as electrocatalysts for carbon dioxide reduction,fuel oxidation,oxygen evolution,and oxygen reduction reactions in the context of sustainable energy conversion.Owing to the exception-ally high surface-to-volume ratio,large surface area as well as their optimized atomic use efficiency,2D materials defined by atomic layers are crucial for surface-related sustainable energy applications.Due to its exceptional properties,such as high conductivity and the ability to enhance the exposure of active metal sites,2D metallenes have recently attracted a lot of interest for use in catalysis,electronics,and energy-related applications.With their highly mobility,adjustable surface states,and electrical struc-tures that can be fine-tuned,2D metallenes are promising nanostructure materials for use in energy con-version with the sustainable applications. 展开更多
关键词 Metallenes ELECTROCATALYSTS Electrochemical processes Atomically thin structure
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Enhanced organic solar cell performance: Multiple surface plasmon resonance and incorporation of silver nanodisks into a grating‐structure electrode 被引量:1
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作者 Thitirat Putnin Chutiparn Lertvachirapaiboon +5 位作者 Ryousuke Ishikawa Kazunari Shinbo Keizo Kato Sanong Ekgasit Kontad Ounnunkad Akira Baba 《Opto-Electronic Advances》 2019年第7期7-20,共14页
In this study, plasmonic nanostructures were examined to enhance the light harvesting of organic thin-film solar cells (OSCs) by multiple surface plasmon resonance (SPR) phenomena originating from the grating-coupled ... In this study, plasmonic nanostructures were examined to enhance the light harvesting of organic thin-film solar cells (OSCs) by multiple surface plasmon resonance (SPR) phenomena originating from the grating-coupled configuration with a Blu-ray Disc recordable (BD-R)-imprinted aluminum (Al) grating structure and the incorporation of a series of silver nanodisks (Ag NDs). The devices with such a configuration maximize the light utilization inside OSCs via light absorption, light scattering, and trapping via multiple surface plasmon resonances. Different types and sizes of metallic nanoparticles (NPs), i.e., gold nanoparticles (Au NPs), Ag nanospheres (Ag NSs), and Ag NDs, were used, which were blended separately in a PEDOT:PSS hole transport layer (HTL). The device structure comprised of grating- imprinted-Al/P3HT:PCBM/Ag ND:PEDOT:PSS/ITO. Results obtained from the J–V curves revealed that the power conversion efficiency (PCE) of grating-structured Al/P3HT:PCBM/PEDOT:PSS/ITO is 3.16%;this value is ~6% higher than that of a flat substrate. On the other hand, devices with flat Al and incorporated Au NPs, Ag NSs, or Ag NDs in the HTL exhibited PCEs ranging from 3.15% to 3.37%. Furthermore, OSCs with an Al grating substrate were developed by the incorporation of the Ag ND series into the PEDOT:PSS layer. Compared with that of a reference device, the PCEs of the devices increased to 3.32%–3.59%(11%–20% improvement), indicating that the light absorption enhancement at the active layer corresponds to the grating-coupled surface plasmon resonance and localized surface plasmon resonance excitations with strong near-field distributions penetrating into the active layer leading to higher efficiencies and subsequent better current generation. 展开更多
关键词 grating-coupled SURFACE PLASMON RESONANCE LOCALIZED SURFACE PLASMON RESONANCE Ag NANODISKS organic solar cells imprinted GRATING
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Apoptotic activity of caged xanthones from Garcinia hanburyi in cholangiocarcinoma cell lines 被引量:5
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作者 Chariya Hahnvajanawong Wongwarut Boonyanugomol +7 位作者 Tapanawan Nasomyon Watcharin Loilome Nisana Namwat Natthinee Anantachoke Wichittra Tassaneeyakul Banchob Sripa Wises Namwat Vichai Reutrakul 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第18期2235-2243,共9页
AIM:To investigate the growth inhibitory mechanism of four caged xanthones from Garcinia hanburyi in cholangiocarcinoma(CCA) KKU-100 and KKU-M156 cells.METHODS:Four caged xanthones,selected on the basis of their antic... AIM:To investigate the growth inhibitory mechanism of four caged xanthones from Garcinia hanburyi in cholangiocarcinoma(CCA) KKU-100 and KKU-M156 cells.METHODS:Four caged xanthones,selected on the basis of their anticancer potency and chemical structure diversities(i.e.isomorellin,isomorellinol,forbesione and gambogic acid) were used in this study.Growth inhibition of these caged xanthones was determined using the sulforhodamine B assay.Induction of apoptosis was assessed by observing cell morphology,ethidium bromide and acridine orange staining and DNA fragmentation assay.Levels of apoptotic-related gene and protein expressions were determined by a real-time reverse transcriptase polymerase chain reaction and Western blotting analysis,respectively.RESULTS:The compounds were found to inhibit growth of both cell lines in a dose-dependent manner and also showed selective cytotoxicity against the cancer cells when compared with normal peripheral blood mononuclear cells.Growth suppression by these compounds was due to apoptosis,as evidenced by the cell morphological changes,chromatin condensation,nuclear fragmentation,and DNA ladder formation.At the molecular level,these compounds induced down-regulation of Bcl-2 and survivin proteins with up-regulation of Bax and apoptosisinducing factor proteins,leading to the activation of caspase-9 and-3 and DNA fragmentation.The functional group variations did not appear to affect the anticancer activity with regard to the two CCA cell lines;however,at a mechanistic level,isomorellinol exhibited the highest potency in increasing the Bax/Bcl-2 protein expression ratio(120 and 41.4 for KKU-100 and KKU-M156,respectively) and in decreasing survivin protein expression(0.01 fold as compared to control cells in both cell lines).Other activities at the molecular level indicate that functional groups on the prenyl side chain may be important.CONCLUSION:Our findings for the first time demonstrate that four caged xanthones induce apoptosis in CCA cells which is mediated through a mitochondriadependent signaling pathway. 展开更多
关键词 Garcinia hanburyi Caged xanthones Human cholangiocarcinoma cell lines APOPTOSIS
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Antibiofilm activity of a-mangostin extracted from Garcinia mangostana L. against Staphylococcus aureus 被引量:3
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作者 Nguyen Thi Mai Phuong Ngo Van Quang +4 位作者 Ta Thu Mai Nguyen Vu Anh Chutima Kuhakarn Vichai Reutrakul Albert Bolhuis 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第12期1154-1160,共7页
Objective: To isolate a-mangostin(AMG) from the peels of mangosteen(Garcinia mangostana L.), grown in Vietnam, and to investigate antibiofilm activity of this compound against three Staphylococcus aureus(S. aureus) st... Objective: To isolate a-mangostin(AMG) from the peels of mangosteen(Garcinia mangostana L.), grown in Vietnam, and to investigate antibiofilm activity of this compound against three Staphylococcus aureus(S. aureus) strains, one of which was methicillin-resistant S. aureus(MRSA) and the other two strains were methicillinsensitive S. aureus(MSSA).Methods: AMG in n-hexane fraction was isolated on a silica gel column and chemically analyzed by HPLC and NMR. The antibiofilm activity of this compound was investigated by using a 96-well plate model for the formation of biofilms. Biofilm biomass was quantified using crystal violet. The viability of cells was observed under confocal microscopy using LIVE/DEAD Bac Light stains. Biofilm composition was determined using specific chemical and enzyme tests for polysaccharide, protein and DNA. Membranedamaging activity was assayed by measuring the hemolysis of human red blood cells in presence of AMG.Results: The results indicated that the isolated AMG, with a purity that exceeded 98%,had minimal inhibitory concentrations in the range of 4.6–9.2 mmol/L for the three strains tested. Interestingly, the MSSA strains were more sensitive to AMG than the MRSA strain. Minimal bactericidal concentrations were 2-fold higher than the minimal inhibitory concentration values for the three strains, indicating that AMG was a bactericidal compound. AMG also prevented biofilm formation effectively, albeit that again the MRSA strain was the most resistant. Interestingly, biofilms of the MRSA strain contained protein as a main component of the extracellular matrix, whereas this was polysaccharide in the MSSA strains. This might relate to the resistance of the MRSA 252 strain to AMG.Assays using human red blood cells indicated that AMG caused significant membrane damage with 50% of cell lysis occurred at concentration of about 36 mmol/L.Conclusions: Our results provide evidence that the isolated AMG has inhibitory activity against biofilm formation by S. aureus, including MRSA. Thus, isolated AMG proposes a high potential to develop a novel phytopharmaceutical for the treatment of MRSA. 展开更多
关键词 α-Mangostin Garcinia mangostana Biofilms Methicillin resistance Staphylococcus aureus
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Toward green syntheses of carboxylates:Considerations of mechanisms and reactions at the electrodes for electrocarboxylation of organohalides and alkenes 被引量:2
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作者 Teera Chantarojsiri Tassaneewan Soisuwan Pornwimon Kongkiatkrai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第12期3046-3061,共16页
Electrosynthesis and carbon dioxide(CO_(2))utilization both have gained interest in recent years due to the efforts to alleviate the climate crisis.Significant progress in the field of electrochemical carboxylation us... Electrosynthesis and carbon dioxide(CO_(2))utilization both have gained interest in recent years due to the efforts to alleviate the climate crisis.Significant progress in the field of electrochemical carboxylation using CO_(2) or electrocarboxylation of organic substrates,particularly organohalides and alkenes,has been made in the past decade.Different components of electrocarboxylation experimental setup as well as the understandings of the mechanism play an important role in the success of the carboxylate syntheses.In this review,overview of the proposed mechanisms and the electrochemical setup are described.The significance of electrochemical components,such as the effect of different cathodes,sacrificial anode materials,and other additives,are explained.The examples of electrocarboxylation for both organohalides and olefins are provided.Lastly,the current trends in the field and future directions are discussed. 展开更多
关键词 ELECTROCARBOXYLATION CO_(2)utilization ELECTROSYNTHESIS CO_(2)coupling Electrochemical method
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A cation-dipole-reinforced elastic polymer electrolyte enabling long-cycling quasi-solid-state lithium metal batteries 被引量:1
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作者 Zhuyi Wang Yiming Wang +3 位作者 Pan Zhai Preeyaporn Poldorn Siriporn Jungsuttiwong Shuai Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第12期340-348,I0009,共10页
The application of ionic liquids(IL)in polymer electrolytes represents a safer alternative to the currently used organic solvents in lithium batteries due to their nonflammability and thermal stability.However,as a pl... The application of ionic liquids(IL)in polymer electrolytes represents a safer alternative to the currently used organic solvents in lithium batteries due to their nonflammability and thermal stability.However,as a plasticizer,it is generally agreed that the introduction of ionic liquid usually leads to a trade-off between ion transport and mechanical properties of polymer electrolyte.Here we report the synthesis of an IL-embedded polymer electrolyte with both high ionic conductivity(2.77×10^(-4)S cm^(-1)at room temperature)and excellent mechanical properties(high tensile strength up to 11.4 MPa and excellent stretchability of 387%elongation at break)achieved by strong ion–dipole interactions between polymer electrolyte components,which was unveiled by the DFT calculation.Moreover,this polymer electrolyte also exhibits nonflammability,good thermal stability and the ability to recover reversibly from applied stress,i.e.,excellent elasticity.This highly viscoelastic polymer electrolyte enables tight interfacial contact and good adaptability with electrodes for stable lithium stripping/plating for 2000 h under a current density of 0.1 mA cm^(-2).By coupling with this polymer electrolyte,the LiFePO_(4)/Li cells exhibit outstanding cycling stability at room temperature as well as the reliability under extreme environmental temperature or being abused. 展开更多
关键词 Elastic polymer electrolyte Ion-dipole interactions High tensile strength Quasi-solid-state lithium battery Long cycling
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Removal of heavy metals from artificial metals contaminated water samples based on micelle-templated silica modified with pyoverdin I 被引量:1
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作者 PANADDA Tansupo WORAKARN Chamonkolpradit +1 位作者 SAKSIT Chanthai CHALERM Ruangviriyachai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期1009-1016,共8页
The micelle-templated silica (MTS) was firstly chemically modified with 3-glycidoxypropyl-trimethoxysilane (GPTMS) before immobilized with pyoverdin I. The characteristics of pyoverdin I-anchored onto the modified... The micelle-templated silica (MTS) was firstly chemically modified with 3-glycidoxypropyl-trimethoxysilane (GPTMS) before immobilized with pyoverdin I. The characteristics of pyoverdin I-anchored onto the modified MTS were investigated using fluorescence, infrared spectra and scanning electron microscopy. The specific surface area of all materials was calculated by Branauer, Emmett and Teller (BET) method using nitrogen isotherm adsorption data. As the results, the surface area of commercial silica gel decreased from 609.2 to 405.4 m2/g, it indicated that the pyoverdin I could be immobilized onto the surface of silica solid support. This adsorbent was used for extraction of Fe(Ⅲ), Cu(Ⅱ), Zn(Ⅱ), and Pb(Ⅱ) in artificial metals contaminated water. Experimental conditions for effective adsorption of trace levels of metal ions were optimized with respect to different experimental parameters using batch procedure. The optimum pH value for the removal of metal ions simultaneously on this adsorbent was 4.0. Complete desorption of the adsorbed metal ions from the adsorbent was carried out using 0.25 mol/L of EDTA. The effect of different cations and anions on the adsorption of these metals on adsorbent was studied and the results showed that the proposed adsorbent could be applied to the highly saline samples and the sample which contains some transition metals. 展开更多
关键词 micelle-templated silica pyoverdin I removal of heavy metals
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Degradation Behaviors of Thai <i>Bombyx mori</i>Silk Fibroins Exposure to Protease Enzymes 被引量:1
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作者 Chuleerat Wongnarat Prasong Srihanam 《Engineering(科研)》 2013年第1期61-66,共6页
The degradation behaviors of Thai Bombyx mori called Samrong and Nanglai silk fibroins exposure to protease enzymes;protease XIV, protease XXIII and α-chymotrypsin type II were studied in this work. The degradation b... The degradation behaviors of Thai Bombyx mori called Samrong and Nanglai silk fibroins exposure to protease enzymes;protease XIV, protease XXIII and α-chymotrypsin type II were studied in this work. The degradation behaviors were expressed by their weight loss, morphological and secondary structure changes as well as thermal properties. Samrong showed higher percentage of weight loss than Nanglai. SEM micrographs indicated that silk fibroin were de- stroyed and showed many holes on their fiber surfaces. All of silk samples were increasable destroyed when exposure to the protease enzyme for long incubation period. With thermal analysis, both silk fibroin presented the thermal stability in the same profile. The result suggested that the selected silk fibroin should be composed of similar pattern of amino acids and their ratios. However, the protease susceptibility of each silk fibroin slightly varied in case of morphology observation. This might be affected by their genetic variety. 展开更多
关键词 Degradation Enzyme PROTEASE Samrong Nanglai
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Synthesis and catalytic performance of bimetallic NiMo-and NiW-ZSM-5/MCM-41 composites for production of liquid biofuels
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作者 Maliwan Subsadsana Pitsanuphong Kham-or +2 位作者 Pakpoom Sangdara Pirom Suwannasom Chalerm Ruangviriyachai 《燃料化学学报》 EI CAS CSCD 北大核心 2017年第7期805-816,共12页
This work presents a synthesis of bimetallic NiMo and NiW modified ZSM-5/MCM-41 composites and their heterogeneous catalytic conversion of crude palm oil( CPO) to biofuels. The ZSM-5/MCM-41 composites were synthesized... This work presents a synthesis of bimetallic NiMo and NiW modified ZSM-5/MCM-41 composites and their heterogeneous catalytic conversion of crude palm oil( CPO) to biofuels. The ZSM-5/MCM-41 composites were synthesized through a self-assembly of cetyltrimethylammonium bromide( CTAB) surfactant with silica-alumina from ZSM-5 zeolite,prepared from natural kaolin by the hydrothermal technique. Subsequently,the synthesized composites were deposited with bimetallic NiMo and NiW by impregnation method. The obtained catalysts presented a micro-mesoporous structure,confirmed by XRD,SEM,TEM,EDX,NH_3-TPD,XRF and N_2 adsorption-desorption measurements. The results of CPO conversion demonstrate that the catalytic activity of the synthesized catalysts decreases in the series of NiMo-ZSM-5/MCM-41 > NiW-ZSM-5/MCM-41 > Ni-ZSM-5/MCM-41 > Mo-ZSM-5/MCM-41 > W-ZSM-5/MCM-41 > NiMo-ZSM-5 > NiW-ZSM-5 > ZSM-5/MCM-41 > ZSM-5 > MCM-41. It was found that the bimetallic NiMo-and NiW-ZSM-5/MCM-41 catalysts give higher yields of liquid hydrocarbons than other catalysts at a given conversion. Types of hydrocarbon in liquid products,identified by simulated distillation gas chromatography-flame ionization detector( SimDis GC-FID),are gasoline( 150-200 ℃; C5-12),kerosene( 250-300 ℃; C5-20) and diesel( 350 ℃; C7-20).Moreover,the conversion of CPO to biofuel products using the NiMo-and NiW-ZSM-5/MCM-41 catalysts offers no statistically significant difference( P> 0.05) at 95% confidence level,evaluated by SPSS analysis. 展开更多
关键词 self-assembly of surfactant ZSM-5/MCM-41 composite micro-mesoporous structure HYDROCRACKING process LIQUID biofuels
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Theoretical study of overstretching DNA–RNA hybrid duplex
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作者 Dong-Ni Yang Zhen-Sheng Zhong +2 位作者 Wen-Zhao Liu Thitima Rujiralai Jie Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期477-485,共9页
DNA–RNA hybrid(DRH) plays important roles in many biological processes. Here, we use a thermodynamic theory to analyze the free energy and unpeeling properties of the overstretching transition for the DRH molecule an... DNA–RNA hybrid(DRH) plays important roles in many biological processes. Here, we use a thermodynamic theory to analyze the free energy and unpeeling properties of the overstretching transition for the DRH molecule and compare the results with double-helix DNA. We report that the RNA strand of DRH is easier to get unpeeled than the DNA strand while the difficulty in unpeeling the double helix DNA lies in between. We also investigate the sequence effect, such as GC content and purine content, on the properties of unpeeling the DRH. Further, to study the temperature effect, the forcetemperature phase diagram of DRH and DNA are calculated and compared. Finally, using a kinetic model, we calculate the force–extension curves in the DRH stretching and relaxation process under different pulling rates and temperatures. Our results show that both pulling rate and temperature have important influences on the stretching and relaxation kinetics of unpeeling the DRH. Putting all these results together, our work provides a comprehensive view of both the thermodynamics and kinetics in DRH overstretching. 展开更多
关键词 DNA–RNA HYBRID mechanical properties overstretching THERMODYNAMIC and KINETIC model
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Determination of Trihalomethanes in Water Samples Using Headspace Solid-Phase Microextraction Gas Chromatography
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作者 Nitaya Saesim Wanna Kanchanamayoon 《Journal of Chemistry and Chemical Engineering》 2010年第6期1-7,共7页
The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromofor... The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromoform. A headspace solid-phase microextraction method has been developed for determination oftrihalomethanes in water samples. The experimental parameters such as the stirring rate, extraction time, extraction temperature and desorption time were investigated. The linearity, detection limits and percentage recovery were evaluated. The optimum conditions were stirring rate 800 rpm/min, extraction time 6 min, extraction temperature 20 ~C, desorption time 2.5 min and desorption temperature 220 ~C. The detection limits were 0.01 ~g/L and the recoveries were in the range of 86-110 %, The proposed method was successfully applied to determination of THM4 in tap water samples. The THM4 contents were varied depending on the sample sites and the season. The total THM4 contents in cool, summer and rainy season were in the range of 27.58-41.89, 32.06-60.73 and 46.26-69.87 p.g/L, respectively. Confirmation of the detected compounds in water samples were performed by gas chromatograph-mass spectrometer. The mass spectra of the target compounds in water samples is in good agreement with trihalomethanes standard spectra. 展开更多
关键词 Water analysis gas chromatography TRIHALOMETHANES disinfection by product solid-phase microextraction.
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Orotate phosphoribosyl transferase mRNA expression and the response of cholangiocarcinoma to 5-fluorouracil
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作者 Chariya Hahnvajanawong Jariya Chaiyagool +6 位作者 Wunchana Seubwai Vajarabhongsa Bhudhisawasdi Nisana Namwat Narong Khuntikeo Banchob Sripa Ake Pugkhem Wichittra Tassaneeyakul 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第30期3955-3961,共7页
AIM:To determine whether expression of certain enzymes related to 5-fluorouracil(5-FU)metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma(CCA).METHODS:The histoculture drug response assay(HDRA)was performe... AIM:To determine whether expression of certain enzymes related to 5-fluorouracil(5-FU)metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma(CCA).METHODS:The histoculture drug response assay(HDRA)was performed using surgically resected CCA tissues.Tumor cell viability was determined morphologically with hematoxylin and eosin-and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues.The mRNA expression of thymidine phosphorylase(TP),orotate phosphoribosyl transferase(OPRT),thymidylate synthase(TS),and dihydropyrimidine dehydrogenase(DPD)was determined with realtime reverse transcriptase-polymerase chain reaction.The levels of gene expression and the sensitivity to 5-FU were evaluated.RESULTS:Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital,Khon Kaen University from 2007 to 2009.HDRA was used to determine the response of these CCA tissues to 5-FU.Based on the dose-response curve,200μg/mL 5-FU was selected as the test concentration.The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU.When the relationship between TP,OPRT,TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined,only OPRT mRNA expression was significantly correlated with the response to 5-FU.The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group(0.41±0.25 vs 0.22±0.12,P<0.05).CONCLUSION:OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA.Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients. 展开更多
关键词 Histoculture drug response assay 5-fluorouracil Cholangiocarcinoma Orotate phosphoribosyl transferase Chemosensitivity
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Ionic liquids for high performance lithium metal batteries 被引量:5
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作者 Kexin Liu Zhuyi Wang +2 位作者 Liyi Shi Siriporn Jungsuttiwong Shuai Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期320-333,I0007,共15页
The pursuit of high energy density has promoted the development of high-performance lithium metal batteries.However,it faces a serious security problem.Ionic liquids have attracted great attention due to their high io... The pursuit of high energy density has promoted the development of high-performance lithium metal batteries.However,it faces a serious security problem.Ionic liquids have attracted great attention due to their high ionic conductivity,non-flammability,and the properties of promoting the formation of stable SEI films.Deeply understanding the problems existing in lithium metal batteries and the role of ionic liquids in them is of great significance for improving the performance of lithium metal batteries.This article reviews the effects of the molecular structure of ionic liquids on ionic conductivity,Li^(+)ion transference number,electrochemical stability window,and lithium metal anode/electrolyte interface,as well as the application of ionic liquids in Li-high voltage cathode batteries,Li-O_(2) batteries and Li-S batteries.The molecular design,composition and polymerization will be the main strategies for the future development of ionic liquid-based electrolytes for high performance lithium metal battery. 展开更多
关键词 Ionic liquids Li+ion conduction Interface issues Lithium metal battery
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Application of PPh3/CI3CCONH2 towards the Glycosylation of Glycosyl Hamiacetals
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作者 Pawarun Chitchirachan Wanchal Pluempanupat 《Journal of Chemistry and Chemical Engineering》 2012年第9期778-784,共7页
Triphenylphosphine coupled with trichloroacetamide was determined to be an effective reagent for the conversion of 2,3,4,6-tetra-O-benzyl-D-glucopyranose as a glycosyl hemiacetal to the corresponding glycosyl chloride... Triphenylphosphine coupled with trichloroacetamide was determined to be an effective reagent for the conversion of 2,3,4,6-tetra-O-benzyl-D-glucopyranose as a glycosyl hemiacetal to the corresponding glycosyl chloride in excellent yield under mild and neutral conditions. Subsequently, the glycosyl chloride was reacted with alcohol or glycosyl acceptors in the presence of zinc(ll) bromide and molecular sieve 5 A to afford the corresponding glycosides in high yields and a-selectivity. This practical and convenient protocol can be utilized for the one-pot glycosylation of glycosyl hemiacetals. 展开更多
关键词 GLYCOSYLATION trichloroacetamide TRIPHENYLPHOSPHINE
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Enhanced adsorption and colorimetric detection of tetracycline antibiotics by using functional phosphate/carbonate composite with nanoporous network coverage 被引量:1
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作者 Pratchayaporn Yukhajon Titikan Somboon Sira Sansuk 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期365-377,共13页
This work presents efficient tetracycline(TC) antibiotics adsorption using a functional porous phosphate/carbonate composite(PCC). The PCC was fabricated by anion-exchange of phosphate on the surface of vaterite-phase... This work presents efficient tetracycline(TC) antibiotics adsorption using a functional porous phosphate/carbonate composite(PCC). The PCC was fabricated by anion-exchange of phosphate on the surface of vaterite-phase calcium carbonate particle scaffolds. The PCC,having dense nanoporous network coverage with large surface area and pore volume, exhibited excellent TC adsorption in solution. Its adsorption isotherm fitted well to the Freundlich model, with a maximum adsorption capacity of 118.72 mg/g. The adsorption process was spontaneous, endothermic, and followed pseudo-second-order kinetics. From the XPS analysis, the hydrogen bonding and surface complexation were the key interactions in the process. In addition, a colorimetric TC detection method was developed considering its complexation with phosphate ions, originating from PCC dissolution, during adsorption.The method was used to detect TC in mg/L concentrations in water samples. Thus, the multifunctional PCC exhibited potential for use in TC removal and environmental remediation. 展开更多
关键词 Porous composite Calcium carbonate TETRACYCLINE ADSORPTION Colorimetric detection Surface complexation
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A Simple Colorimetric Procedure for the Determination of Iodine Value of Vegetable Oils Using a Smartphone Camera
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作者 Nipat Peamaroon Jaroon Jakmunee Nuntaporn Moonrungsee 《Journal of Analysis and Testing》 EI 2021年第4期379-386,共8页
A smartphone camera-based colorimetric method is developed for the determination of iodine value of vegetable oils.The small amount of Wijs reagent is employed for halogenation of the unsaturated sites of the sample.T... A smartphone camera-based colorimetric method is developed for the determination of iodine value of vegetable oils.The small amount of Wijs reagent is employed for halogenation of the unsaturated sites of the sample.The rest of unreacted reagent is transformed into iodine,which further reacts with the starch solution to form the blue color complex.The free download smartphone application is used for measuring the blue color intensity.More than one sample can be measured by taking only one photo shot.Under the controlled illuminance,the calibration graph for measuring the iodine values of various vegetable oils is constructed from the dissolved triiodide.The detection and quantitation limits are less than 0.02 and 0.032 mM I;,respectively.This method provides a better determination result of the iodine value compared with the standard titrimetric method.This method is convenient,simple,rapid,inexpensive,and easy operation with few chemical waste products. 展开更多
关键词 Smartphone camera COLORIMETRY Iodine value Wijs reagent Vegetable oil
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