bluuebunny/crossref_metadata_2025_split huggingface dataset:
Artificial ageing of wood finishes monitored by IR analysis and color measurements
Authors: Irmouli Youcef , George Béatrice , Merlin André 
Published: October 2011

AbstractPhotocurable finishes appear now as very attractive products for industrial wood joinery for reducing volatile organic compounds (VOC). Nevertheless their poor durability is currently reported. In this study, we aimed to enhance stability of advanced formulations based on photoinitiators working under UV‐visible light by introducing UV absorbers, the absorption band of which is shifted compared to the band of initiators. We tested the efficiency of these stabilizers for two curable coatings applied onto oak and spruce. Modifications of samples at molecular and macroscopic scales were quantified after an accelerated ageing process by FTIR spectroscopy, measurements of color variations, apparition of cracks. It appears that both UV absorbers tested do not greatly improve the durability of systems and the results obtained allow to better understand the causes of the poor characteristics of the finishing systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis, characterization, and thermal analysis of two polymeric chromium ternary complexes with nitrilotriacetic acid and alanine or glycine
Authors: Ismail Eman H. , Souaya Eglal R. , Mohamed Amr A. 
Published: October 2011

AbstractTwo chromium ternary complexes with nitrilotriacetic acid as a primary ligand and alanine or glycine as secondary ligand were prepared in slightly acidic medium. The structure of these two complexes was characterized using elemental, thermal analysis, FTIR spectra, and the two complexes mass spectra. The spectroscopy data suggest that these two complexes were in polymeric form and have the monomeric unit H[Cr(HNTA)(Hala)(SO4)] and H[Cr(HNTA)(Gly)(SO4)] in which sulfate group act as a bidentate ligand linked between each monomeric unit for the same complex. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Intumescent flame retardant TPO composites: Flame retardant properties and morphology of the charred layer
Authors: Wang Xu , Feng Na , Chang Suqin , Zhang Guixia , Li Hong , Lv Hongfei 
Published: October 2011

AbstractIntumescent flame retardant thermoplastic polyolefin (TPO) composites were prepared to study the relationships between their structure of charred layer (including of the multicellular intumescent layer and the charry layer) and flame retardant properties. They were characterized using the LOI and UL‐94 test, which indicated that the best fire retardant behavior (V‐0 rating and LOI reach to 28.1%) was obtained at the formulation of TPO/ammonium dihydrogen phosphate/starch (100/60/20). Thermal gravimetric analysis demonstrated that the presence of ammonium dihydrogen phosphate/starch promoted the esterification and carbonization process in lower temperature range while enhancing the thermal stability of intumescent flame retardant TPO in high‐temperature range. Scanning electron microscope and optical microscope were shown that, with combustion time prolonged, the intumescent layers obtained greater number of cells, and the charry layer became more compact while the size of the carbon granules became smaller on the surface. Introduction of starch had an obvious effect on the structure of the intumescent and charry layers. The charry layer of the composites with the content of 20 phr starch was more compact and uniform than that of the composites with 50 phr. The weight ratio of ammonium dihydrogen phosphate to starch in the intumescent flame retardant was fixed as 3 : 1 which cooperated with each other well to promote a compact charry layer and to obtain the better flame retardancy performance. Therefore, the better the charred layers produced, and the better flame retardant properties they obtained. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of colloidal β‐cyclodextrins–Fe3O4 magnetic nanoparticles on the chemiluminescence enhancement of luminol–Ag(III) complex for rapid and sensitive determination of cysteine in human serum
Authors: Rezaei B. , Ensafi A. A. , Zarei L. , Kameli P. 
Published: October 2011

ABSTRACTColloidals solution of Fe3O4 magnetic nanoparticles (MNPs), capped with β‐cyclodextrins (β‐CD) as inclusion complexes, were found to enhance the chemiluminescence (CL) intensity of the luminol–diperiodatoargentate(III) (DPA) system. On injection of cysteine into the luminol–DPA–β‐CD–Fe3O4 MNPs inclusion complexes system, the CL intensity is strongly enhanced. The enhanced CL signal is ascribed to the catalytic effect of Fe3O4 MNPs capped with β‐CD, which is assumed to stabilize the CL intermediate. Based on these findings, a rapid and sensitive assay was developed for the determination of cysteine in human serum. The effects of analytical variables on the CL signal were studied and optimized. Under the optimum conditions, the CL intensity was directly proportional to the concentration of cysteine in the range 8.0 × 10–9–1.0 × 10–6 mol/L. The detection limit was 2.8 × 10–9 mol/L (3 Sb/m) and the relative standard deviation (RSD) for 10 replicate determinations of 1.0 × 10–7 mol/L cysteine was 3.5%. The proposed method was applied to the sensitive determination of cysteine in human serum samples, and compared with the Ellman method with satisfactory results. Copyright © 2011 John Wiley & Sons, Ltd.
Steam reforming of ethanol on a Ni/Al2O3 catalyst coupled with a hydrotalcite‐like sorbent in a multilayer pattern for co2 uptake
Authors: Cunha A. F. , Wu Y. J. , Díaz Alvarado F. A. , Santos J. C. , Vaidya P. D. , Rodrigues A. E. 
Published: October 2011

AbstractSteam reforming of ethanol (SRE) on a Ni/Al2O3 catalyst was studied. The effects of the operating conditions and catalyst nature on the course of reaction were evaluated. Hydrogen was generated in the temperature range between 100 and 600°C. A mechanism was used to explain the reaction pathways. A commercial hydrotalcite‐like sorbent arranged in a multilayer pattern of catalyst and sorbent was used for CO2‐uptake to enhance hydrogen production. The concept of sorption enhanced reaction process on SRE is illustrated by the operation of catalyst and CO2‐sorbent at 400°C. A lower flow rate regime and multilayer pattern system enhances hydrogen production in the initial breakthrough periods. CO appears in traces in the product gas stream. © 2011 Canadian Society for Chemical Engineering
Extraction and Determination of Quercetin and Myricetin from Chamaecyparis obtusa by Ionic Liquids‐based Monolithic Cartridge
Authors: Zhu Tao , Bi Wentao , Row Kyungho 
Published: October 2011

AbstractA short ionic liquids (ILs)‐based monolithic cartridge was prepared and used as the selective extraction sorbent. After the material was evaluated by field emission‐scanning electron microscopy (FE‐SEM), a new approach for the extraction and determination of quercetin and myricetin from Chamaecyparis obtusa (C. obtusa) by using ILs‐based, monolithic cartridge system was developed. Chromatographic analysis was conducted on a C18 column with UV detection at 372 nm, an eluting solution consisting of acetonitrile‐water (25/75,V/V) as the mobile phase, and a flow rate of 0.7 mL·min−1. A good linear relationship was demonstrated when the concentrations of quercetin and myricetin were in the range of 0.5–100.0 µg·mL−1. The recoveries ranged from 101.6% to 104.6% and the inter‐ and intra‐day relative standard deviations (RSD) were less than 5.0%. This method effectively removed the impurities and avoided tedious pretreatment. It provided a fast, economic and effective method for assaying trace drugs from natural plants.
Robust CoAl Alloy: Highly Active, Reusable and Green Catalyst in the Hydrogenolysis of Glycerol
Authors: Guo Xiaoyang , Yin Anyuan , Guo Xiaodong , Guo Xiuying , Dai Weilin , Fan Kangnian 
Published: October 2011

AbstractCoAl alloy catalyst is found, for the first time, to be highly active, selective and reusable for the synthesis of diols via the hydrogenolysis of glycerol under mild conditions. The products and the catalyst could be self‐separated from the reaction system through a simple reactor.
Eco‐friendly and Efficient Synthesis of 2,3‐Dihydroquinazolin‐4(1H)‐ones
Authors: Majid Ghashang , Kobra Azizi , Hamed Moulavi‐Pordanjani , Hamid Reza Shaterian 
Published: October 2011

AbstractA simple and facile method for the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐ones through the direct cyclocondensation of one‐pot three‐component cyclocondensation of isatoic anhydride, ammonium acetate (or primary amines) and aldehydes; and anthranilamide and aldehydes using silica supported ferric chloride (SiO2‐FeCl3) as catalyst under solvent‐free conditions is described.
(+)‐Tartaric Acid‐Catalyzed High Regio‐ and Stereoselective Aminobromination of Olefins
Authors: Chen Zhanguo , Wei Junfa , Li Wenli , Wang Yun , Zhao Pengfei , Shi Xianying 
Published: October 2011

Abstract(+)‐Tartaric acid‐catalyzed aminobromination of α,β‐unsaturated ketones, α,β‐unsaturated esters and simple olefins utilizing TsNH2/NBS as the nitrogen/halogen sources at room temperature without protection of inert gases achieved good yields (up to 92% yield) of vicinal haloamino products with excellent regio‐ and stereoselectivity, even just 10% of (+)‐tartaric acid was used as catalyst. The regio‐ and stereochemistry was unambiguously confirmed by X‐ray structural analysis of products 2b and 12c. The electron‐rich and deficient olefins show significant differences in activity to the aminobromination reaction and give the opposite regioselectivities. The 21 cases have been investigated which indicated that our protocol has the advantage of a large scope of olefins. Additionally, tartaric acid as catalyst has the advantage of avoiding any hazardous metals retained in products.
Effect of Poly(ethylene glycol)‐400 and Carbon on MoO3 Nanocomposite Materials and Its Catalytic Activity
Authors: Navgire Madhukar , Yelwande Ajeet , Arbad Balasaheb , Lande Machhindra 
Published: October 2011

AbstractThe effect of addition of poly(ethylene glycol)‐400 (PEG‐400) and carbon (0, 1, 2 and 3 wt%) as substrates were investigated systematically to get the desired phase of carbon‐doped MoO3 material. The carbon source was prepared from the Acacia arabica plant wood. The resulting samples were calcined at 500°C. The effect of PEG‐400 and carbon composite on the structure, particle size and morphology were investigated. The prepared samples were characterized by XRD, SEM‐EDS and FT‐IR techniques. The samples with PEG‐400 and carbon addition give better control of particle size and porosity. The prepared catalysts were tested for the synthesis of 3,4‐dihydropyrimidones via the Biginelli‐type condensation reaction. This new method consistently has the advantage of excellent yields (88%–93%) and short reaction times (1.5–3 h) than do classical Biginelli reaction conditions.
Mn(III)‐Mediated Chlorination of Conjugated Ketones
Authors: Liu Xingchao , Wang Lu , Zou Jianping 
Published: October 2011

AbstractMn(III)‐Cl formed by the reaction of Mn(OAc)3 and hydrochloric acid in situ, reacted with α,β‐unsaturated ketones readily to afford α,β‐dichloroketones in good yields under mild conditions. The products are key precursors for synthesis of conjugated alkynones and other organic compounds.
Microwave‐Assisted Aqueous Synthesis: A Rapid Approach to Poly‐functionalized Indoline‐Spiro Benzofurodiazepines
Authors: Wang Shuliang , Cheng Chuang , Gong Feng , Wu Feiyue , Jiang Bo , Zhou Jianfeng , Tu Shujiang 
Published: October 2011

AbstractNew cycloaddition has been established for the synthesis of indoline‐spiro benzofurodiazepine derivatives. Those reactions were conducted by reacting readily available and inexpensive starting materials, such as benzene‐1,2‐diamines, tetronic acid and indoline‐2,3‐diones, in aqueous solution under microwave irradiation. When mono‐substituted benzene‐1,2‐diamines as an amine component was employed, the reaction regioselectively resulted in the poly‐functionalized indoline‐spiro benzofurodiazepine with good yields. The present green synthesis shows attractive characteristics such as the use of water as reaction media, concise one‐pot conditions, short reaction periods, easy work‐up/purification and reduced waste production without the use of any strong acids or metal promoters.
Convenient Synthesis of 3,5‐Biscarbamoyl‐pyridine Derivatives
Authors: Wang Xiayun , Zhu Yiwen , Zhang Min , Lu Dongliang , Qian Qun , Chen Yali , Cao Weiguo , Song Liping , Deng Hongmei 
Published: October 2011

AbstractAn efficient and convenient method for synthesis of 3,5‐bis‐carbamoyl‐2,6‐dimethylpyridine derivatives was achieved in good to excellent yields by reaction of anilines with 3,5‐bis(3′,5′‐dimethyl‐1′‐pyrazolyl‐carbonyl)‐2,6‐dimethylpyridine, in which pyrazoles served as leaving groups. The structures of products were confirmed by spectra data and microanalysis.
Determination of Parathion‐methyl in Vegetables by Fluorescent‐Labeled Molecular Imprinted Polymer
Authors: Sun Qian , Yao Qianqian , Sun Zhoulin , Zhou Tianshu , Nie Dongxia , Shi Guoyue , Jin Litong 
Published: October 2011

Abstract A novel sensor for the determination of parathion‐methyl based on couple grafting of functional molecular imprinted polymers (MIPs) was fabricated which is developed by anchoring the MIP layer on surfaces of silica particles embedded CdSe quantum dots by surface imprinting technology. The synthesized molecular imprinted silica nanospheres (CdSe@SiO2@MIP) allow a high selectivity and sensitivity of parathion‐methyl via fluorescence intensity decreasing when the MIP material rebinding the parathion‐methyl molecule. Compared with the MIP fabricated in traditional method, the template of parathion‐methyl was easier to remove from the CdSe@SiO2@MIP imprinted material. Under optimal conditions, the fluorescence intensity of parathion‐methyl at the imprinted sensor was detected by spectrofluorophotometer. The relative fluorescence intensity of CdSe@SiO2@MIP decreased linearly with the increasing concentration of parathion‐methyl ranging from 0.013 mg·kg−1 to 2.63 mg·kg−1 with a detection limit (3δ) of 0.004 mg·kg−1 (S/N=3), which is lower than the MIP in tradition. The imprinted film sensor was applied to detect parathion‐methyl in vegetable samples without the interference of other organophosphate pesticides and showed a prosperous application in the field of food safety.
Preconcentration/Separation of Some Metal Ions Using Sodium Dodecyl Sulfate Coated Alumina Modified with Bis(5‐bromo‐2‐hydroxy‐benzaldehyde)‐2‐methyl‐1,5‐pentane Diimine (BBHBPDI) Prior to Their Flame‐AAS Determination
Authors: Ghaedi Mehrorang , Montazerozohori Morteza , Marahel Farzaneh , Nejati Biareh Mehdi , Soylak Mostafa 
Published: October 2011

AbstractPreconcentration/separation of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions using bis(5‐bromo‐2‐hydroxy‐benzaldehyde)‐2‐methyl‐1,5‐pentane diimine (BBHBPDI) on SDS coated alumina has been reported. The influences of the analytical parameters including pH, ligand and SDS amount, type and concentration of eluent and sample volume on metal ions recoveries were investigated. At optimum values of all variables the relative standard deviation are between 2.5–2.7 and preconcentration factor was 375, while recoveries for all understudy metal ions are higher than 95%, determination limits are between 1.5–2.7. The method has been successfully applied to determination of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions content in some real samples.
A Sensitive Simultaneous Determination of Adrenalin and Paracetamol on a Glassy Carbon Electrode Coated with a Film of Chitosan/Room Temperature Ionic Liquid/Single‐Walled Carbon Nanotubes Nanocomposite
Authors: Babaei Ali , Babazadeh Mitra , Afrasiabi Mohammad 
Published: October 2011

AbstractThe present work demonstrates that simultaneous determination of adrenalin (AD) and paracetamol (PAR) can be performed on single‐walled carbon nanotube/chitosan/ionic liquid modified glassy carbon electrode (SWCNT‐CHIT‐IL/GCE). The electro‐oxidations of AD and PAR were investigated with cyclic voltammetry (CV), differential pulse voltammetry (DPV) and also chronoamperometry (CA) methods. DPV experiments showed that the oxidation peak currents of AD and PAR are proportional to the corresponding concentrations over the 1–580 μmol/L and 0.5–400 μmol/L ranges, respectively. The RSD at a concentration level of 15 μmol/L AD and 15 μmol/L PAR were 1.69% and 1.82%, respectively. Finally the modified electrode was used for simultaneous determination of AD and PAR in real samples with satisfactory results.
Influence from Thermal Elimination Temperature of Precursor Polymer and Film‐forming Methods on the Photophysics of the Poly(2,5‐didodecyloxy‐p‐phenylenevinylene)
Authors: Wang Shangli , Zhao Wei , Xu Xiaoqian , Cheng Si , Fan Lijuan 
Published: October 2011

AbstractA series of poly(p‐phenylenevinylene)s (PPVs) with good solubility were synthesized from thermal elimination of precursor poly(2,5‐didodecyloxy‐p‐phenylenevinylene) at different temperature via Wessling method. The polymer photophysics were influenced by the thermal elimination condition, which was consistent with NMR and IR characterizations. The additional absorption peak at longer wavelength and the red‐shifted emission maximum both in solution and in film, for PPVs obtained at high elimination temperature, indicated the existence of longer conjugated blocks in these systems. The emission maximum for drop‐cast film (436 nm) for PPV obtained under 200°C (PPV200) was 16 nm blue shifted to the spin‐coated films (452 nm) or 29 nm to the solution (465 nm). The SEM study showed drop‐cast film had the morphology of isolated conjugated particles in the matrix while blurry linear structure was found for spin‐coated film, which was consistent with the photophysics. The discussion about this difference was carried out based on the consideration of the flexibility of the polymer chains and different conjugated length of PPV in different states.
Prognostic value of positive human epidermal growth factor receptor 2 status and negative hormone status in patients with T1a/T1b, lymph node‐negative breast cancer
Authors: Livi Lorenzo , Meattini Icro , Saieva Calogero , Franzese Ciro , Di Cataldo Vanessa , Greto Daniela , Franceschini Davide , Scotti Vieri , Bonomo Pierluigi , Nori Jacopo , Sanchez Luis , Vezzosi Vania , Bianchi Simonetta , Cataliotti Luigi , Biti Giampaolo 
Published: October 2011

AbstractBACKGROUND:The objective of this study was to evaluate prognostic factors of local and distant recurrence in patients diagnosed with T1a and T1b, lymph node‐negative breast carcinoma (BC) with emphasis on human epidermal growth factor receptor 2 (HER2) status.METHODS:The authors reviewed 704 women with T1aT1bN0M0 BC who received treatment at the Radiation‐Oncology Center of Florence University between November 2002 and December 2008. Patients with ductal carcinoma in situ or recurrent BC at presentation and patients who received adjuvant chemotherapy were excluded from the analysis.RESULTS:In total, 75 patients had HER2‐positive BC (10.7%). At a mean follow‐up of 4.9 years (standard deviation, 2.6 years; range, 0.5‐10.8 years), 19 events were identified, including 10 distant recurrences. Patients with HER2‐positive BC had worse distant recurrence‐free survival (DRFS) than patients with HER2‐negative BC (hazard ratio, 3.66; 95% confidence interval, 0.94‐14.69; P = .045). Negative hormone receptor (HR) status was associated significantly with worse DRFS (hazard ratio, 0.26; 95% confidence interval, 0.07‐0.93; P = .026). In multivariate analysis, younger age was the only significant risk factor for an event of recurrence (hazard ratio, 0.61;95% confidence interval, 0.20‐1.82; P = .029).CONCLUSIONS:The current results indicated that patients with T1a/T1b, lymph node‐negative BC have a low risk of distant and local recurrence, but younger age is a significant risk factor for events occurrence. Young women with HER2‐positive and HR‐negative status have a significant risk of distant recurrence and should be considered for future clinical trials with anti‐HER2 adjuvant therapy. Cancer 2011. © 2011 American Cancer Society.
Single‐stage single‐switch PFC converter for wide‐input extreme step‐down voltage applications
Authors: Ismail Esam H. , Al‐Saffar Mustafa A. , Sabzali Ahmad J. , Zerai Adel A. 
Published: October 2011

SUMMARYThis paper presents a new single‐stage single‐switch high power factor correction AC/DC converter suitable for low‐power applications (< 150 W) with a universal input voltage range (90–265 Vrms). The proposed topology integrates a buck–boost input current shaper followed by a buck and a buck–boost converter, respectively. As a result, the proposed converter can operate with larger duty cycles compared with the existing single‐stage single‐switch topologies, hence, making them suitable for extreme step‐down voltage conversion applications. Several desirable features are gained when the three integrated converter cells operate in discontinuous conduction mode. These features include low semiconductor voltage stress, zero‐current switch at turn‐on, and simple control with a fast well‐regulated output voltage. A detailed circuit analysis is performed to derive the design equations. The theoretical analysis and effectiveness of the proposed approach are confirmed by experimental results obtained from a 100‐W/24‐Vdc laboratory prototype. Copyright © 2011 John Wiley & Sons, Ltd.
The (β‐Diketiminato)bismuth(III) Complex [LBiCl(μ‐Cl)]2 {L = HC[(CMe)(NAr)]2, Ar = 2,6‐iPr2C6H3} and Its Derivatives: The Presence of Versatile Ligand Ligation Modes
Authors: Li Yan , Zhu Hongping , Tan Gengwen , Zhu Tao , Zhang Jinyuan 
Published: October 2011

AbstractThe reaction of BiCl3 with LLi {L = HC[(CMe)(NAr)]2, Ar = 2,6‐iPr2C6H3} in a molar ratio of 1:1 was carried out under various conditions and afforded [LBiCl(μ‐Cl)]2 (1), [L′BiCl(μ‐Cl)]2 [4; L′ = N(Ar)=C(Me)CH=C(NHAr)CH2], and L″Bi2Cl4 [5; L″ = N(Ar)=C(Me)CC(Me)=N(Ar)]. Compounds 1 and 4 are isomers, and a thermal conversion of 1 to 4 was realized. In this reaction system, when a little excess nBuLi and BiCl3 were used, [LBiCl(μ‐Cl)Bi(nBu)Cl(μ‐Cl)]2 (2) was isolated as side product after the isolation of 1. The reaction of 1 with AgOOCCF3 in the absence of light from –15 °C to room temperature generated LBi(OOCCF3)2 (3). Finally, the solvent‐free reaction of BiCl3 and LH at elevated temperature (125 °C) under vacuum gave [LH2]+[BiCl4(THF)]– (6) in a low yield. The formulations of all these complexes have been confirmed by 1H and 13C NMR spectroscopy and X‐ray crystallography, except for 6, which was only identified by X‐ray crystallography due to its insolubility in organic solvents. These complexes exhibit versatile L ligation modes at the metal atom and reveal the complexity of the reaction between BiCl3 and LLi.