Thermal Poling of Soda‐Lime Silica Glass with Nonblocking Electrodes—Part 1: Effects of Sodium Ion Migration and Water Ingress on Glass Surface Structure

It is generally well known that not only the sodium itself, but also the non‐bridging oxygen (NBO) sites associated with sodium ions are largely responsible for the surface reactivity of soda‐lime‐silica (SLS) glass. Thermal poling can modify the distribution of sodium in the subsurface region. In this work, a commercial SLS float glass was thermally poled using nonblocking electrodes in air. The Na⁺?depleted anode surface and the Na⁺?gradient cathode surface were characterized using a variety of methods to find the compositional, structural and morphological effects of thermal poling. Of particular significance is the use of nondestructive vibrational spectroscopy methods, which can lead to new and improved understanding of water interactions with sodium and its sites in the glass. It was found that during thermal poling, the Na⁺?depleted glass network on the anode side undergoes condensation reactions of NBO sites accompanied by the increase in concentrations of silanol (SiOH) groups and molecular water species. In contrast, silanol and water species do not increase and the silicate network change is negligible in the Na⁺?gradient cathode side. Vibrational sum frequency generation (SFG) spectroscopy analysis revealed the difference in distributions of hydrous species in the Na⁺?depleted and Na⁺?gradient surfaces. The structural information of the thermally‐poled surfaces provides critical insights needed to understand the mechanical and mechanochemical properties of the Na⁺?concentration modified SLS glass surfaces reported in the Part 2 companion paper.     

Synthesis of chiral stationary phase via surface‐initiated atom transfer radical polymerization of vinylated cellulose 3,5‐dimethylphenylcarbamate

A polysaccharide‐immobilized chiral stationary phase (CSP) was prepared by the surface‐initiated atom transfer radical polymerization (SI‐ATRP), in pyridine, of cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate), having a polymerizable vinyl group, on the surface of SiO₂ support. The successful preparation of the CSP was confirmed via Fourier transform infrared spectroscopy, field‐emission scanning electron microscopy, X‐ray photoelectron spectroscopy, elemental analysis and thermal analysis. The chiral recognition ability of the prepared CSP was evaluated with high‐performance liquid chromatography using 10 racemates with various mobile phases of hexane/alcohol, hexane/tetrahydrofuran and hexane/chloroform. As a result, this CSP prepared using SI‐ATRP can be used in tetrahydrofuran and chloroform solutions as eluents. Copyright © 2011 Society of Chemical Industry     

Temporary Increase of PPAR-γ and Transient Expression of UCP-1 in Stromal Vascular Fraction Isolated Human Adipocyte Derived Stem Cells During Adipogenesis

In this study, cells from the stromal vascular fraction of human subcutaneous tissues were induced to differentiate toward adipose cells in vitro for 2 weeks. During adipogenic differentiation, we followed the chronological changes in their morphology with Coherent anti-Stokes Raman scattering (CARS) microscopy and checked the PPAR-γ and UCP-1 expression with RT-PCR. On day 4 after inducing adipogenic differentiation, CARS imaging showed multiple small lipid droplets (LD) distributed peripherally along the cellular membrane. PPAR-γ began to express at this time and increased until day 14 at a steady rate. On day 7, the cells appeared as brown adipocytes with numerous small LD throughout the cytoplasm, and the mRNA level of UCP-1 rose abruptly by 6- to 7-fold. After an additional 7 days, CARS imaging showed the development of a large LD, which is characteristic of white adipocytes, and the mRNA level of UCP-1 slumped significantly. These results demonstrate the possibility that ADSC pass through a brown adipocyte-like stage while differentiating into white adipocytes.     

Interfacial adhesion reaction of polyethylene and starch blends using maleated polyethylene reactive compatibilizer

The interfacial reaction of the polyethylene (PE)/starch blend system containing the reactive compatibilizer maleated polyethylene (m‐PE) was directly characterized by Fourier transform infrared (FTIR) spectroscopy. A significant amount of anhydride groups on m‐PE existed as hydrolyzed forms, resulting in a large amount of carboxyl groups. Using a vacuum‐heating‐cell designed in the laboratory, the carboxyl groups were successfully transformed into the dehydrolyzed state (i.e., anhydride group). This result enabled the direct spectroscopic observation of chemical reaction occurring at the interface. For the PE/starch blend system containing m‐PE, the chemical reaction at the interface was verified by the evolution of ester and carboxyl groups in the FTIR spectra. The effect of the reactive compatibilizer on the interfacial morphology was also examined by scanning electron micrography (SEM). Enhanced interfacial adhesion was clearly observed for the blend system containing reactive compatibilizer. Tensile strengths of blend systems containing m‐PE also increased noticeably compared with the corresponding system without compatibilizer. A similar observation was made for the breaking elongation data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 767–776, 2002     

Immobilization of a cyclodextrin glucanotransferase (CGTase) onto polyethylene film with a carboxylic acid group and production of cyclodextrins from corn starch using CGTase‐immobilized PE film

Carboxylic acid groups were introduced onto polyethylene (PE) film by radiation‐induced graft copolymerization. Subsequently, the clodextrin glucanotransferase (CGTase) was immobilized on the PE film with a carboxylic acid group. The activity of the immobilized CGTase on PE film was in the range of 0.40–1.04 U/cm² per min. The production of cyclodextrins (CDs) from corn starch was examined using the CGTase‐immobilized PE film. The production ratios of CDs using CGTase‐immobilized PE film was in the following order: α–CD > β–CD > γ–CD. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2451–2457, 2002     

Synthesis and biological activity of phthalimide‐based polymers containing 5‐fluorouracil

The attachment of anticancer agents to polymers is a promising approach towards reducing the toxic side‐effects and retaining the potent antitumour activity of these agents. A new tetrahydrophthalimido monomer containing 5‐fluorouracil (ETPFU) and its homopolymer and copolymers with acrylic acid (AA) and with vinyl acetate (VAc) have been synthesized and spectroscopically characterized. The ETPFU contents in poly(ETPFU‐co‐AA) and poly(ETPFU‐co‐VAc) obtained by elemental analysis were 21 mol% and 20 mol%, respectively. The average molecular weights of the polymers determined by gel permeation chromatography were as follows: M_n = 8900 g mol^?1, M_w = 13 300 g mol^?1, M_w/M_n = 1.5 for poly(ETPFU); M_n = 13 500 g mol^?1, M_w = 16 600 g mol^?1, M_w/M_n = 1.2 for poly(ETPFU‐co‐AA); M_n = 8300 g mol^?1, M_w = 11 600 g mol^?1, M_w/M_n = 1.4 poly(ETPFU‐co‐VAc). The in vitro cytotoxicity of the compounds against FM3A and U937 cancer cell lines increased in the following order: ETPFU > 5‐FU > poly(ETPFU) > poly(ETPFU‐co‐AA) > poly(ETPFU‐co‐VAc). The in vivo antitumour activities of all the polymers in Balb/C mice bearing the sarcoma 180 tumour cell line were greater than those of 5‐FU and monomer at the highest dose (800 mg kg^?1). © 2002 Society of Chemical Industry     

Evidence of Correlation between Electronic Density and Surface Acidity of Sulfated TiO2

Correlation between the electronic structure and surface acidity of TiO₂–SO₄ ^2– with different SO₄ ^2– amounts has been investigated by means of NH₃-TPD, NH₃-FT-IR and XPS. With the increase of sulfate loadings, the shift of binding energies of O 1s in hydroxyl and Ti 2p_2/3 increases and is proportional to total acidity. A linear relation is obtained between Ti 2p binding energy shift and Lewis acid sites, while the shift in O 1s binding energy is attributed both to the generation of NH₃ hydrogen bond and of Brønsted acid sites. Accordingly, the results obtained from XPS measurements provide evidence that the ammonia adsorption sites are attributed to the decrease of electron density of O 1s in hydroxyl (Brønsted type and H bonded) and Ti 2p_2/3 (Lewis type) by inductive effect of the neighboring sulfate ion.     

Effect of coupling agent content on properties of composites made from polylactic acid and chrysanthemum waste

Chrysanthemum flower is among one of the highly sought after and widely planted flower crops, in particular for cultural and religious ceremonies. However, the chrysanthemum stem and stalk have little value and usually discard as by‐product waste from floristry. The objective of this research is to investigate the potential value of utilizing chrysanthemum stem and stalk as reinforcing fillers for thermoplastic composites. In this study, 2‐mm thick composite sheet containing predefined formulations of polylactic acid (PLA), chrysanthemum waste filler (CWF) ranging from 15 to 60 phr, and maleated polyethylene (MAPE) coupling agent up to 5 phr were prepared with the aid of Haake internal mixer and compression molding. The effect of MAPE loading on tensile, thermal, and morphological properties of PLA/CWF composites was investigated. The findings revealed that PLA/CWF composite attained improved tensile modulus compared to the neat PLA, and the tensile modulus increases with higher concentration of CWF. However, both tensile strength and elongation at break reduces with increase loading of CWF. Overall, PLA/CWF composites with MAPE shows better performance compared to those without MAPE, where an optimum strength of 21.8 MPa can be achieved with 60 phr CW and 3 phr MAPE. The measured tensile strength is comparable to alternatives natural fiber thermoplastic composites demonstrating its potential to be used in non‐structurally demanding application. J. VINYL ADDIT. TECHNOL., 26:10–16, 2020. © 2019 Society of Plastics Engineers     

Phorbol 12-Myristate 13-Acetate Induced Toxicity Study and the Role of Tangeretin in Abrogating HIF-1α-NF-κB Crosstalk In Vitro and In Vivo

Phorbol 12-myristate 13-acetate (PMA) is a potent tumor promoter and highly inflammatory in nature. Here, we investigated the toxic effects of PMA on different model system. PMA (10 μg) caused chromosomal aberrations on the Allium cepa root tip and induced mitotic dysfunction. Similarly, PMA caused embryonic and larval deformities and a plummeted survivability rate on zebrafish embryo in a dose-dependent manner. Persistently, PMA treatment on immortalized human keratinocyte human keratinocyte (HaCaT) cells caused massive inflammatory rush at 4 h and a drop in cell survivability at 24 h. Concomitantly, we replicated a cutaneous inflammation similar to human psoriasis induced by PMA. Herein, we used tangeretin (TAN), as an antagonist to counteract the inflammatory response. Results from an in vivo experiment indicated that TAN (10 and 30 mg/kg) significantly inhibited PMA stimulated epidermal hyperplasia and intra-epidermal neutrophilic abscesses. In addition, its treatment effectively neutralized PMA induced elevated reactive oxygen species (ROS) generation on in vitro and in vivo systems, promoting antioxidant response. The association of hypoxia-inducible factor 1-alpha (HIF-1α)-nuclear factor kappa-light-chain-enhancer of activated b cells (NF-κB) crosstalk triggered by PMA enhanced PKCα-ERK1/2-NF-κB pathway; its activation was also significantly counteracted after TAN treatment. Conclusively, we demonstrated TAN inhibited the nuclear translocation of HIF-1α and NF-κB p65. Collectively, TAN treatment ameliorated PMA incited malignant inflammatory response by remodeling the cutaneous microenvironment.     

Preparation of dual‐layer acetylated methyl cellulose hollow fiber membranes via co‐extrusion using thermally induced phase separation and non‐solvent induced phase separation methods

Dual‐layer acetylated methyl cellulose (AMC) hollow fiber membranes were prepared by coupling the thermally induced phase separation (TIPS) and non‐solvent induced phase separation (NIPS) methods through a co‐extrusion process. The TIPS layer was optimized by investigating the effects of coagulant composition on morphology and tensile strength. The solvent in the aqueous coagulation bath caused both delayed liquid–liquid demixing and decreased polymer concentration at the membrane surface, leading to porous structure. The addition of an additive (triethylene glycol, (TEG)) to the NIPS solution resolved the adhesion instability problem of the TIPS and NIPS layers, which occurred due to the different phase separation rates. The dual‐layer AMC membrane showed good mechanical strength and performance. Comparison of the fouling resistance of the AMC membranes with dual‐layer polyvinylidene fluoride (PVDF) hollow fiber membranes fabricated with the same method revealed less fouling of the AMC than the PVDF hollow fiber membrane. This study demonstrated that a dual‐layer AMC membrane with good mechanical strength, performance, and fouling resistance can be successfully fabricated by a one‐step process of TIPS and NIPS. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42715.