bluuebunny/crossref_metadata_2025_split huggingface dataset:
Highly branched phenolic resin‐grafted silicone rubber copolymer for high efficiency ablation thermal protection coating
Authors: Li Boqian , He Chen , Cao Min , Ren Ying , Wang Junshan , Lu Wu 
Published: August 2019

ABSTRACTHighly branched phenolic resin‐grafted silicone rubber (PGS) was synthesized by grafting allyl ether phenolic resin onto silicone rubber with Si─H groups via hydrosilylation. The chemical structure of the copolymer was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and gel permeation chromatography, and its microphase morphology was observed via scanning electron microscopy (SEM). The mechanical properties and thermal stability of the material were also characterized. Thereafter, an ablation thermal protection coating (ATPC) based on PGS as the polymer matrix was prepared. In comparison with silicone rubber‐based ATPC, the PGS‐based ATPC showed better thermal stability and a stronger char layer. After oxygen–acetylene testing, the micromorphology and chemical composition of the PGS‐based ATPC were characterized via SEM, energy‐dispersive spectrometry, and X‐ray diffraction. Finally, the PGS‐ and silicone rubber‐based ATPCs were subjected to a heat flow of 370 kW m−2 for 70 s, the background temperature of the PGS‐based ATPC was only 70 °C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48353.
Preparation of high‐performance reverse osmosis membrane by zwitterionic polymer coating in a facile one‐step way
Authors: Xia Yu , Dai Xiaojun , Gai Jing‐Gang 
Published: August 2019

ABSTRACTAiming at preparing high‐performance polyamide (PA) reverse osmosis (RO) membrane in a facile and high effective way, the codeposition strategy of dopamine and zwitterionic polymer was first applied to modify PA RO membrane. The noncovalent bonds between dopamine and Poly [2‐(Methacryloyloxy)ethyl]dimethyl‐(3‐sulfopropyl)ammonium hydroxide (PSPE) act to fix PSPE onto the membrane surface and simultaneously destroy the interaction force between dopamine aggregations so that the modified layer could equably form on the PA layer. PSPE significantly improved the hydrophilicity [the water contact angle (WCA) of S‐D‐3 is 25.3°] of the modified membrane. And, the smoother surface was noticed on the modified membrane. All of these endow the PSPE/dopamine modified membrane superb water flux (the maximum water flux is 51.86 L m−1 h−1 at 1.6 MPa and 25 °C) and impressive antifouling and anti‐adhesion properties to bovine serum albumin (BSA) (protein), sodium dodecyl sulfate (anionic surfactant), and dodecyl trimethyl ammonium bromide (cationic surfactant) with salt retention was well maintained. Notably, in the BSA fouling test, nearly 100% of the flux recovery ratio was achieved. This method is promising to be employed in industrial scale‐up production. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48355.
Quantification and elucidation of the UV‐light triggered initiation kinetics of TPO and BAPO in liquid acrylate monomer
Authors: Ruhland Klaus , Habibollahi Fereshteh , Horny Robert 
Published: August 2019

ABSTRACTThe initiation kinetics of two important UV‐light‐triggered initiators for the radical polymerization [diphenyl‐2,4,6‐trimethyl benzoyl phosphine oxide (TPO) and phenyl‐bis(2,4,6‐trimethyl benzoyl) phosphine oxide (BAPO)] has been quantified in dependence on the initiator concentration (0.25–2 mol %), the light intensity at 365 nm (0–2000 mW cm−2), the thickness of the sample (50–200 μm), the temperature (25–80 °C), the monomer [2‐ethyl hexyl acrylate (EHA) and 2‐ethyl hexyl methacrylate (EHMA)] and the atmosphere (oxygen free and air) directly in the liquid acrylate monomer. The determination of the kinetic parameters was done by applying two independent procedures: (1) following the initiator decay with respect to the irradiation time, evaluated by radiometric measurements of the UV‐light absorption at 365 nm and (2) via titration of the initiation process by using defined under‐stoichiometric to stoichiometric amounts of TEMPO as inhibitor, evaluated by means of FTIR‐ATR spectroscopy. The validity of the titration procedure was proven by means of 13C and 31P NMR studies of 13C‐labeled TPO and was explained by a Lewis acid/base interaction between the carbonyl carbon of the initiator and the oxygen of TEMPO. Both methods resulted in very close kinetic parameters. Thus, reliable values for the extinction coefficients ε365 at 365 nm, for the effective rate constants of the α cleavage (containing the quantum yield and the initiator efficiency) when dissolved in the liquid monomer could be provided for both initiators for the first time. The effect of dioxygen quenching in dependence of sample thickness and the temperature dependence on the initiation step were evaluated. EHA was compared with EHMA as liquid monomer, and a yet unmentioned inhibition in case of EHMA was discovered. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48357.
NIR‐shielding films based on PEDOT‐PSS/polysiloxane and polysilsesquioxane hybrid
Authors: Tsukada Satoru , Nakanishi Yuki , Kai Hiroyuki , Ishimoto Takayoshi , Okada Kenta , Adachi Yohei , Imae Ichiro , Ohshita Joji 
Published: August 2019

ABSTRACTNear‐infrared (NIR)‐shielding films based on polysiloxane or polysilsesquioxanes and poly(3,4‐ethylenedioxythiophene)‐poly(4‐styrene sulfonate) (PEDOT‐PSS) were synthesized via a sol–gel reaction. Phase‐separated mixtures of tetraethyl orthosilicate (TEOS) or methyltriethoxysilane (MTES) with an aqueous dispersion of PEDOT‐PSS formed deep‐blue homogeneously dispersed sols after stirring. Thin films were prepared by depositing the resulting homogeneously dispersed sols on a glass substrate by spin coating and heating. PEDOT‐PSS/TEOS films maintained uniform flat surfaces after 10 coatings. MTES‐based films exhibited mottled patterns with nonuniform surfaces. The 10‐layer TEOS‐based film has high NIR‐shielding properties with moderately visible transmittance. NIR absorption by the PEDOT‐PSS/TEOS hybrid suppresses air temperature elevation. The five‐layer TEOS‐based film showed similar NIR‐shielding ability and slightly lower visible light transmittance compared with tin‐doped indium oxide glass. The 10‐layer TEOS‐based film exhibited a 15.6% lower temperature rise than the uncoated glass substrate. Specifically, this is an environmentally friendly NIR‐shielding material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48367.
Recycling by injection and chrome plating of acrylonitrile–butadiene–styrene parts pickled in hydrochloric and nitric acids
Authors: Kurek Ana Paula , Ranzan Taise , Cardoso Isabel Narloch , Dotto Marta Elisa Rosso , Balzer Palova Santos , Sellin Noeli 
Published: August 2019

ABSTRACTChrome‐plated acrylonitrile–butadiene–styrene(ABS) parts with defects in the metal layer were submitted to pickling with hydrochloric and nitric acids and recycled by injection in different proportions with neat ABS. For comparison, samples with neat ABS (ABSn) and ABS submitted to pickling (ABSp) were also injected. The influence of the pickled material on the samples properties was evaluated by chemical, thermal, and mechanical analysis. The injected samples were chrome by conventional process and evaluated by visual inspection, adhesion test, resistance to corrosion, and accelerated aging test, to evaluate the quality of the chrome finish. A gradual darkening of samples and formation of carbonyl groups with the increase in the pickled ABS concentration and little influence on the melt flow index were observed. The samples exhibited one thermal degradation stage similar to ABSn. The increase in the pickled ABS percentage caused a slight increase in glass‐transition temperature of polybutadiene phase, and did not influence the tensile properties and hardness of samples, but decreased the impact resistance. After chrome plating, all samples were approved for visual inspection and metal layer adhesion test. Only the sample injected with pickled ABS was reproved in corrosion test, due to the oxidation of the chrome layer. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48372.
Branched poly(biphenylene‐co‐sulfone)ether ion exchange membranes containing perfluorocyclobutane groups for fuel cell applications
Authors: Moon Su‐Young , Kim Jeong‐Hoon , Chang Bong‐Jun 
Published: August 2019

ABSTRACTA series of branched poly(biphenylene‐co‐sulfone) ion exchange membranes containing perfluorocyclobutane groups were prepared for fuel cells. Two bifunctional trifluorovinyloxy‐terminated monomers (sulfonable 4,4′‐bis(trifluorovinyloxy)biphenyl and insulfonable 4,4′‐sulfonyl‐bis(trifluorovinyloxy)biphenyl) and a trifunctional trifluorovinyloxy‐terminated branching agent (1,1,1‐tris(4′‐trifluorovinyloxyphenyl)ethane) were synthesized and terpolymerized via thermal [2π + 2π] cyclodimerization to obtain partially fluorinated and branched polymers containing 0–5 mol% of the branching agent. They were then postsulfonated by chlorosulfonic acid at room temperature, cast as membranes, and characterized to evaluate their electrochemical properties for fuel cell applications. As the branching agent content was increased, their polydispersity values highly increased, indicating they became highly branched. It was confirmed that higher branching agent content also increased the ion exchange capacity, water uptake, and proton conductivity of the branched ion exchange membranes containing perfluorocyclobutane groups. This indicates that their electrochemical properties can be easily controlled by the degree of branching. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48373.
Ginsenoside Rg1‐modified PHBV fibrous scaffold reduces interleukin‐1 beta‐induced dedifferentiation of articular chondrocytes
Authors: Li Yongsheng , Zhong Risheng , Zhou Zheng , Liu Hairong , Dai Yao , Hu Yibing 
Published: August 2019

ABSTRACTInflammatory environment in the end‐stage osteoarthritis (OA) cartilage defects greatly limits the effectiveness of engineered cartilage. It is critical that developing scaffolds intend to be applied in cartilage tissue engineering (CTE) under this pathological condition. In this study, poly(3‐hydroxybutyric acid‐137‐3‐hydroxyvaleric acid) (PHBV) fibrous scaffolds modified by ginsenoside Rg1 could be able to alleviate the dedifferentiation of articular chondrocytes caused by interleukin‐1 beta (IL‐1β), a key inflammatory factor in the pathogenesis of OA. Followed by 5‐day incubation with culture media containing IL‐1β, articular chondrocytes cultured with ginsenoside Rg1‐modified PHBV fibrous scaffolds (PHBV‐g‐Rg1) displayed typical chondrocytic morphology compared with those cultured with PHBV fibrous scaffolds. By employing real‐time quantitative polymerase chain reaction assay, it demonstrated that PHBV‐g‐Rg1 fibrous scaffold reduced IL‐1β‐caused dedifferentiation to articular chondrocytes via enhancing the transcription of chondrocytic phenotype‐related genes and reducing the transcription of matrix degradation‐related genes. It suggests that ginsenoside Rg1‐modified PHBV fibrous scaffold would be potentially applied in CTE to treat cartilage defects under IL‐1β threat. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48378.
Controlled stimulation‐burst targeted release by pH‐sensitive HPMCAS/theophylline composite nanofibers fabricated through electrospinning
Authors: Liu Mengzhu , Wang Xin , Wang Yongpeng , Jiang Zhenhua 
Published: August 2019

ABSTRACTHPMCAS/theophylline composite nanofibers, which displayed a significant pH‐responsive behavior, were successfully fabricated through electrospinning. SEM observations demonstrated that the nanofibers were linear with a smooth and unordered structure. Mean diameter of the composite nanofibers increased with the content of drug. FT‐IR spectra confirmed that theophylline was successfully loading into HPMCAS nanofibers. XRD, DSC, and TGA verified that theophylline blended with HPMCAS in a physical level and had retained its crystalline state in the composite nanofibers, which further demonstrated that the drug efficacy did not destroy in the electrospinning process. Drug loading testing showed that drug loading percent and encapsulation efficiency increased with the content of drug, except the 4% drug content sample, which was confirmed to be decided by the beaded morphology. Furthermore, the in vitro drug release studies revealed that the composite nanofibers particularly showed rapid theophylline release at weak alkaline pH environment and exhibited a burst release in the first hour followed by a decreased tendency. However, the release ratio was still at a high level after 12 h. The release process can be helpful to the urgent sudden disease, meanwhile to reduce the suffering of patients and the required frequency of drug administration. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48383.
Core‐crosslinking as a pathway to develop inherently antibacterial polymeric micelles
Authors: Kadayifci Melike Seyma , Gokkaya Damla , Topuzogullari Murat , Isoglu Sevil Dincer , Atabey Tugba , Arasoglu Tulin , Ozmen Mehmet Murat 
Published: August 2019

ABSTRACTPositively charged polymeric materials have been an alternative to combat bacteria as they exhibit inherently antibacterial potency via bacteria membrane disruption. In this study, we report facile preparation of positively charged core‐crosslinked polymeric micelles with inherent antibacterial properties. Spherical micelles were prepared by self‐assembling of poly(4‐vinylpyridine)‐b‐(oligoethylene glycol methyl ether methacrylate) copolymer in aqueous solution. Herein, quaternization reaction was utilized for the first time to core crosslink the micelles through the pyridine rings utilizing their hydrophobic core and thus resulting positively charged nanostructures. Dynamic light scattering (DLS) results identified that the micelles have an average hydrodynamic diameter of 114 nm with a polydispersity index ranging between 0.105 and 0.114. The electrophoretic light scattering (ELS) measurements demonstrated that the micelles have zeta potential values ranging from +38 to +63 mV. It was evident from both ELS and DLS results that the micelles in solution exhibit long‐term stability as the samples were able to maintain their size and charge even after a year of storage. Further, the micelles exhibited inherently antibacterial activity against Escherichia coli and furthermore, this antibacterial efficacy was sustained over a period of 1 year. These stable core‐crosslinked micelles are proposed to have great potential as antibacterial materials for long‐term applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48393.
Detecting exchange networks in New Britain, Papua New Guinea: geochemical comparisons between axe‐adze blades and in situ volcanic rock sources
Authors: PENGILLEY ALANA , BRAND CHRISTABEL , FLEXNER JAMES , SPECHT JIM , TORRENCE ROBIN 
Published: August 2019

ABSTRACTCompared to elsewhere in Oceania, the history and character of stone axe‐adze production and exchange in the Bismarck Archipelago is very poorly known. To explore the feasibility of using geochemical analysis to trace past social interaction, we conducted a non‐destructive portable XRF study of 97 ground stone artefacts from archaeological contexts in New Britain and the ethnographic collection at the Australian Museum. The study capitalised on the well‐documented spatial distribution of geochemical variation resulting from the plate‐tectonic history of the region. The results indicate that prehistoric communities in New Britain specialised in goods such as ground stone tools or obsidian in order to facilitate social interaction over a large region.
Genetic Deficiency of Interferon‐γ Reveals Interferon‐γ–Independent Manifestations of Murine Hemophagocytic Lymphohistiocytosis
Authors: Burn Thomas N. , Weaver Lehn , Rood Julia E. , Chu Niansheng , Bodansky Aaron , Kreiger Portia A. , Behrens Edward M. 
Published: August 2019

ObjectiveFamilial hemophagocytic lymphohistiocytosis (FHLH) is a complex cytokine storm syndrome caused by genetic abnormalities rendering CD8+ T cells and natural killer cells incapable of cytolytic killing. In murine models of FHLH, interferon‐γ (IFNγ) produced by CD8+ T cells has been identified as a critical mediator of disease, and an IFNγ‐blocking antibody (emapalumab) has recently been approved by the Food and Drug Administration. However, development of hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS) in patients who are genetically unresponsive to IFNγ questions the absolute necessity of IFNγ in driving disease. This study was undertaken to determine the necessity of IFNγ in driving HLH.MethodsIFNγ−/−Prf1−/− mice were infected with lymphocytic choriomeningitis virus (LCMV), and HLH immunopathologic features, including survival, weight loss, cytopenias, cytokine profiles, and immune cell phenotypes, were assessed. Mixed bone marrow chimeras were created to determine the immune cell–intrinsic role of IFNγ receptor signaling. CD8+ T cell depletion and interleukin‐33 (IL‐33)/ST2 blockade were performed using monoclonal antibodies.ResultsLCMV infection of IFNγ−/−Prf1−/− mice resulted in severe HLH‐like disease. CD8+ T cells and the IL‐33/ST2 axis remained essential mediators of disease; however, IFNγ‐independent HLH immunopathology correlated with a 10–15‐fold increase in neutrophilia (P < 0.001) and an altered cytokine milieu dominated by IL‐6, IL‐1β, and granulocyte–macrophage colony‐stimulating factor (GM‐CSF) (P < 0.05). Furthermore, IFNγ regulated CD8+ T cell expression of GM‐CSF and neutrophil survival.ConclusionIFNγ is not necessary for the development of fulminant HLH, requiring physicians to consider case‐by‐case treatment strategies. Use of therapies that target upstream activators of CD8+ T cells, such as IL‐33/ST2 signaling, may be more universally applicable treatment options that ameliorate both IFNγ‐dependent and ‐independent manifestations of HLH/MAS.
Intrinsic Emission from Nanographenes
Authors: Yamato Kairi , Sekiya Ryo , Nishitani Shohei , Haino Takeharu 
Published: August 2019

AbstractTop‐down approaches have been widely used as convenient methods for the production of nanographenes. To understand the photoemission properties of nanographenes, their separation and the optical properties of the individual fractions is important. By using a combination of size‐exclusion and silica‐gel‐adsorption chromatography, we separated lipophilic nanographenes that contained para‐methoxybenzyl groups. The mixture consisted of large (average 19.8 nm) and small (average 4.9 nm) nanographenes, whilst unreacted carboxy groups remained in the latter group. Optical measurements revealed that oxygen‐containing functional groups had little influence on the photoemission of the nanographenes, thus indicating that the intrinsic emission, that is, emission from the sp2 surfaces, was responsible for the photoemission. Two photoemission bands were observed for all of the fractions, which likely originated from the edge and inner parts of nanographene.
Conformational Effects of [Ni2(μ‐ArS)2] Cores on Their Electrocatalytic Activity
Authors: Mondragón‐Díaz Alexander , Robles‐Marín Elvis , Murueta‐Cruz Brenda A. , Aquite Juan C. , Martínez‐Alanis Paulina R. , Flores‐Alamo Marcos , Aullón Gabriel , Benítez Luis Norberto , Castillo Ivan 
Published: August 2019

AbstractTwo nickel complexes supported by tridentate NS2 ligands, [Ni2(κ‐N,S,S,S′‐NPh{CH2(MeC6H2R′)S}2)2] (1; R′=3,5‐(CF3)2C6H3) and [Ni2(κ‐N,S,S,S′‐NiBu{CH2C6H4S}2)2] (2), were prepared as bioinspired models of the active site of [NiFe] hydrogenases. The solid‐state structure of 1 reveals that the [Ni2(μ‐ArS)2] core is bent, with the planes of the nickel centers at a hinge angle of 81.3(5)°, whereas 2 shows a coplanar arrangement between both nickel(II) ions in the dimeric structure. Complex 1 electrocatalyzes proton reduction from CF3COOH at −1.93 (overpotential of 1.04 V, with icat/ip≈21.8) and −1.47 V (overpotential of 580 mV, with icat/ip≈5.9) versus the ferrocene/ferrocenium redox couple. The electrochemical behavior of 1 relative to that of 2 may be related to the bent [Ni2(μ‐ArS)2] core, which allows proximity of the two Ni⋅⋅⋅Ni centers at 2.730(8) Å; thus possibly favoring H+ reduction. In contrast, the planar [Ni2(μ‐ArS)2] core of 2 results in a Ni⋅⋅⋅Ni distance of 3.364(4) Å and is unstable in the presence of acid.
Maternal Obesity/Diabetes, Plasma Branched‐Chain Amino Acids, and Autism Spectrum Disorder Risk in Urban Low‐Income Children: Evidence of Sex Difference
Authors: Panjwani Anita A. , Ji Yuelong , Fahey Jed W. , Palmer Amanda , Wang Guoying , Hong Xiumei , Zuckerman Barry , Wang Xiaobin 
Published: August 2019

Maternal metabolic conditions are known risk factors for child autism spectrum disorder (ASD). Branched‐chain amino acids (BCAAs) are also associated with ASD. We examined the joint associations of maternal metabolic conditions and BCAAs on the risk of child ASD and whether the associations differed by child's sex. We analyzed 789 mother–infant pairs, a subset of the Boston Birth Cohort, from a predominantly urban, low‐income, minority population. Maternal plasma BCAAs were measured by liquid chromatography–tandem mass spectrometry in samples collected 24–72 hr postpartum. A composite BCAA score was created using factor analysis, and prepregnancy obesity and diabetes (ob/DM) were combined into one variable. Logistic regression was used to explore the role of BCAAs as mediators or cofactors with ob/DM and child's sex on ASD risk. BCAA‐ob/DM and BCAA‐sex interactions were also examined. Maternal BCAAs alone were not associated with ASD and did not mediate the path between ob/DM and ASD. In the presence of maternal ob/DM, BCAA score was significantly associated with ASD (adjusted OR 2.33, 95% CI 1.18, 4.60). Interactions were present for valine with ob/DM and for valine and isoleucine with male sex on ASD risk. The odds ratio (OR) for risk of ASD was the greatest with all three risk factors combined—male sex, above median BCAA score, and ob/DM (OR 10.79, 95% CI 4.40, 26.42). Similar patterns were found for other developmental disorders, though not as strong as for ASD. Additional studies are warranted to clarify the role of maternal BCAAs, ob/DM, and child's sex in ASD. Autism Res 2019, 12: 1562–1573. © 2019 International Society for Autism Research, Wiley Periodicals, Inc.Lay SummaryThis study investigated whether maternal obesity/diabetes and maternal circulating branched‐chain amino acids (BCAAs) can jointly affect child ASD risk and whether the associations differ by child's sex. We found that the risk of ASD was greater among mothers with obesity/diabetes who also had elevated concentrations of BCAAs and that this risk was even greater for male children. These findings provide new evidence on fetal origins of ASD and sex difference and warrant additional investigation.