bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Integrated X‐ray Powder Diffraction (XRPD) and Molecular Dynamics (MD) Approach for Modelling Mixed‐Metal (Zn, Al) Layered Double Hydroxides (LDHs)
Authors: Lombardo Giuseppe M. , Pappalardo Giuseppe C. , Punzo Francesco , Costantino Ferdinando , Costantino Umberto , Sisani Michele 
Published: November 2005

AbstractA combination of experimental (XRPD) and computational (MD‐simulation) techniques was used for a detailed study of the structural, dynamic and hydration properties of the ZnAl layered double hydroxides (LDHs) of formula [Zn0.65Al0.35(OH)2]Cl0.35·yH2O (I) and [Zn0.65Al0.35(OH)2](CO3)0.175·yH2O (II), with y = 0.35 and 0.69, respectively. Our approach was based on a direct comparison made, for the firsttime, between the observed XRPD diffraction pattern and the MD‐simulated pattern of each model that was considered. The XRPD curve is affected (reflection angles and line shapes) by dynamic and structural factors, and the interlayer distribution of the water content. Accordingly, its reproduction through MD modelling is the most suitable means of monitoring these properties of the material. Molecular modelling was performed by MD simulations of models of I and II built up through appropriate modifications of their interlayer total water contents and related distribution. The validated models, namely those that provided the best MD‐simulated pattern of I and II, were then used to determine structures and features which have not been previously determined by conventional diffraction techniques. The calculated XRPD curves were corrected to take into account the “size” broadening effect. The approach provided structural data that matched well those obtained by Rietveld analyses for the usual parameters. Furthermore, the study was original in its capability to detect and thus to discriminate between the different interatomic distances Zn–O, Al–O, Al···Al, Zn···Zn, Zn···Al in the slabs. The MD‐simulated models of I and II provided the best reproduction of the XRPD curves for total water of hydration contents of y = 0.25 and y = 0.69, respectively. In the case of II, a domain with a homogeneous distribution of total water contents predominated. Conversely, in the case of I, a nonhomogeneous distribution featured by two (or multiple) shared crystalline domains having different interlayer water contents was evidenced.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
The Mechanism of Magnetic Interaction in Spin‐Ladder Molecular Magnets: A First‐Principles, Bottom‐Up, Theoretical Study of the Magnetism in the Two‐Legged Spin‐Ladder Bis(2‐amino‐5‐nitropyridinium) Tetrabromocuprate Monohydrate (Eur. J. Inorg. Chem. 23/2005)
Authors: Deumal Mercé , Giorgi Giacomo , Robb Michael A. , Turnbull Mark M. , Landee Christopher P. , Novoa Juan J. 
Published: November 2005

AbstractThe cover picture shows the properties of the antiferromagnetic molecular spin‐ladder built by combining the 5NAP+ diamagnetic cations and the CuBr42− radical anions. The upper left box shows the structure of the two ions, the middle box its magnetic topology (the weakly interacting two‐leg ladders are clearly marked), while the lower box shows the experimental and computed magnetic susceptibility curves. Details are discussed in the article by M. Deumal, J. J. Novoa et al. on p. 4697 ff.
The Mechanism of Semibullvalene Bromination
Authors: Wang Selina C. , Tantillo Dean J. 
Published: November 2005

AbstractA mechanism for semibullvalene bromination is proposed based on quantum chemical calculations. This mechanism involves concerted bromine addition and cyclopropane ring‐opening to form an allylic cation, without the intermediacy of a bromonium or a cyclopropylcarbinyl cation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Advances in capillary electrophoretically mediated microanalysis: An update
Authors: Zhang Jie , Hoogmartens Jos , Van Schepdael Ann 
Published: November 2005

AbstractThis review, as a continuation of an earlier report, gives an overview of recent developments, over the period from 2003 until now, in the use of capillary electrophoretic techniques for the in‐line study of enzymatic reactions, derivatization, and chemical reactions. The article is divided into two parts: (i) in‐line enzymatic reactions and (ii) in‐line derivatization and chemical reactions. The first part introduces electrophoretically mediated microanalysis (EMMA) and discusses and illustrates the different modes of EMMA. A literature overview on enzymatic reactions is provided. The second part starts with an introduction of the procedures and the nomenclature used in the area of in‐line derivatization and chemical reactions based on EMMA. Reported derivatization and chemical reaction procedures are discussed and summarized.
Synthesis of a new sulfonated monomer for poly(aryl ether)s
Authors: McKay Scott E. , Lashlee Robert W. , Marshall Tadd P. , Kopitzke Robert W. 
Published: November 2005

AbstractA new sulfonated monomer suitable for polyarylether synthesis was made. 1,1'‐(p‐Phenylenedioxy)bis[4‐(4‐fluorobenzoyl)]benzene was prepared from phosphorus pentoxide/methanesulfonic acid (PPMA), 1,4‐diphenoxybenzene, and p‐fluorobenzoic acid in good yield. This compound was selectively monosulfonated on the most activated ring with fuming sulfuric acid and isolated as the sodium salt. Poly(aryl ethers) made from this monomer may find use as proton exchange membranes. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:553–556, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20137
Reactivity of terminal transition metal borylene complexes
Authors: Braunschweig Holger , Rais Daniela 
Published: November 2005

AbstractThe chemistry of terminal transition metal borylene complexes is reviewed, with particular attention to recent developments concerning the reactivity of these species. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:566–571, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20143
Synthesis and antimicrobial activity of novel 3 substituted 1,5‐dihydro‐2,4,3‐benzodioxaphosphepine 3‐oxides
Authors: Haranath P. , Babu M. F. Stephen , Anasuyamma U. , Raju C. Naga , Reddy C. Suresh 
Published: November 2005

AbstractNovel 3 substituted 1,5‐dihydro‐2,4,3‐benzodioxaphosphepine 3‐oxides (5a–h) were synthesized by reacting 1,2‐benzenedimethanol (1) with phosphorus tribromide in the presence of triethylamine at 0–30°C and subsequent reaction of the monobromide (2) with different Grignard reagents (3) at room temperature. The products (4) were converted to corresponding oxides 5a–i by oxidation with H2O2 at room temperature. The chemical structures of all the products were confirmed by analytical, IR and NMR (1H, 13C, and 31P) spectral data. Their antifungal and antibacterial activity is also evaluated. Most of these compounds exhibited moderate antimicrobial activity in the assay. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:572–575, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20154
Phosphorylation of N‐iso‐propyl‐ and N‐tert‐butylpyrroles with phosphorus(III) halides
Authors: Chaikovskaya Aleksandra A. , Dmitriv Yurii V. , Ivonin Sergei P. , Pinchuk Aleksandr M. , Tolmachev Andrei A. 
Published: November 2005

AbstractThe investigation concerns the effect of a bulky substituent at the pyrrole nitrogen atom on the orientation and regioselectivity of pyrrole phosphorylation with phosphorus(III) halides. As shown, phosphorylation of N‐iso‐propylpyrrole with phosphorus tribromide or trichloride proceeds nonregioselectively at positions 2 and 3 but it is followed by the 2 → 3 migration of the dihalogenophosphine group which quantitatively yields the 3‐isomer. N‐tert‐butylpyrrole is regioselectively phosphorylated with halogenophosphines at position 3. The tert‐butyl substituent at the nitrogen atom does not preclude the binding of even two or three pyrrolyl residues to the phosphorus atom. The key compounds, 3‐pyrrolyldihalogenophosphines, were isolated in a pure state, characterized and used to obtain a number of stable phosphorus(V) derivatives. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:599–604, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20158
A facile stereoselective synthesis of (E)‐α‐silylvinyl sulfides via hydromagnesiation of alkynylsilanes
Authors: Cai Mingzhong , Xia Jun , Wang Pingping 
Published: November 2005

AbstractHydromagnesiation of alkynylsilanes 1 in diethyl ether gave (Z)‐α‐silylvinyl Grignard reagents 2, which reacted with arylsulfenyl chlorides 3 to afford stereoselectively (E)‐α‐silylvinyl sulfides 4 in good yields. (E)‐α‐Silylvinyl sulfides 4 could undergo the cross‐coupling reactions with Grignard reagents in the presence of NiCl2(PPh3)2 to give stereoselectively (Z)‐1,2‐disubstituted vinylsilanes 5. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:644–647, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20165
Phosphorylation of imidazo[2,1‐b]thiazoles with phosphorus(III) halides in the presence of bases
Authors: Zarudnitskii Evgenij V. , Yurchenko Aleksandr A. , Merkulov Anatolij S. , Semenova Marina G. , Pinchuk Aleksandr M. , Tolmachev Andrej A. 
Published: November 2005

AbstractThe reaction of phosphorus(III) halides with 6‐substituted imidazo[2,1‐b]thiazoles in the presence of bases proceeds regioselectively and affords 5‐phosphinoimidazo[2,1‐b]thiazoles, useful synthons for the preparation of various P(III) and P(V) derivatives. 5‐Phosphinoimidazo[2,1‐b]thiazoles are selectively alkylated at the phosphorus or heterocyclic nitrogen atom, depending on the alkylating agent. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:648–655, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20166
Synthesis and crystal structure of 10a‐oxo‐1‐phenylimino‐ 10‐propyl‐3,4,10,10a‐tetrahydro‐1H‐ 2‐thia‐4a,10‐diaza‐10aλ5‐ phospha‐phenanthren‐9‐one
Authors: Chen Hui , Huang Junmin , Chen Ruyu 
Published: November 2005

AbstractThe title novel fused tricyclic phosphoroheterocycle, C19H20N3O2PS, was synthesized in an excellent yield of 88.5% via the reac‐ tion of 1‐(2‐bromoethyl)‐2,3‐dihydro‐3‐propyl‐1,3,2‐benzodiazaphosphorin‐4(1H)‐one 2‐oxide with phenyl isothiocyanate, which contains the proximate imino and phosphoryl groups in the fused heterocycle. The crystallographic data analysis reveals that the title compound crystallizes into triclinic space group P with unit cell parameters: a = 9.159(3) Å, b = 10.463(4) Å, c = 10.698(4) Å, α = 88.090(6)°, β = 86.921(6)°, γ = 70.528(6)°, V = 965.0(6) Å3 for Z = 2 and there is a fused three‐ring in the molecule. The structure has been solved by direct methods and refined to R = 0.0424 for 2451 observed reflections with I >2 σ(I). The proximate imino and phosphoryl groups are not coplanar because both are jointly located in the fused heterocycle, thus having ring tension and this then destroys the conjugation between the CN and the PO moieties. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:671–676, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20169
Synthesis, characterization, and in vitro 5‐Fu release behavior of poly(2,2‐dimethyltrimethylene carbonate)‐poly(ethylene glycol)‐poly(2,2‐dimethyltrimethylene carbonate) nanoparticles
Authors: Zhang Ying , Zhuo Ren‐xi 
Published: November 2005

AbstractNovel ABA‐type amphiphilic triblock copolymers composed of poly (ethylene glycol) (PEG) as hydrophilic segment and poly (2,2‐dimethyltrimethylene carbonate) (PDTC) as hydrophobic segment were synthesized by ring‐opening polymerization of 2,2‐dimethyltrimethylene carbonate (DTC) initiated by dihydroxyl PEG. The influence of introducing PEG block on crystalline behavior of PDTC segment was investigated by DSC. Polymeric micelles in aqueous medium were characterized by fluorescence spectroscopy and dynamic light scattering. The critical micelle concentration of these copolymers was in the range of 5.1–50.5 mg/L. Particle size was 80–280 nm. Core‐shell–type nanoparticles were prepared by the dialysis technique. Zeta potential was measured by laser Doppler anemometry, and all nanoparticles had negative zeta potential. Transmission electron microscopy images demonstrated that these nanoparticles were spherical in shape. Anticancer drug 5‐fluorouracil (5‐Fu) as a model drug was loaded in the polymeric nanoparticles. X‐ray powder diffraction demonstrated that 5‐Fu was encapsulated into polymeric nanoparticles as molecular dispersion. In vitro cytotoxicity of nanoparticles was evaluated by MTT assay. In vitro release behavior of 5‐Fu was investigated, and sustained drug release was achieved. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Formaldehyde biodegradation in the presence of methanol under denitrifying conditions
Authors: Eiroa Marta , Vilar Almudena , Kennes Christian , Veiga María C 
Published: November 2005

AbstractSimultaneous formaldehyde and methanol biodegradation and also denitrification were studied in batch assays and in a continuous laboratory‐scale reactor. In batch assays, high formaldehyde concentrations (up to 1360 mg dm−3) were removed under anoxic conditions in the presence of methanol. It was found that formaldehyde biodegradation produced methanol and formic acid as products. The denitrification process was affected by the initial formaldehyde concentration. In the continuous reactor, the biodegradation of different concentrations of formaldehyde (1500–275 mg dm−3) and methanol (153–871 mg dm−3) took place, maintaining the organic loading rate at 0.84 g COD dm−3 d−1 (COD/N 4). However, each increase in the methanol concentration in the influent caused a decrease in the denitrification level. An adaptation period to methanol was necessary before the denitrification percentage could be recovered. In contrast with batch assays, in the continuous reactor methanol and formic acid were not detected in the effluent. Moreover, in the continuous reactor the denitrification percentages were higher and the nitrite accumulation was lower. Copyright © 2005 Society of Chemical Industry
Oxidative conversion of propane to acrylic acid and acetic acid over mixed oxide catalysts
Authors: Rane Vilas H , Rodemerck Uwe , Baerns Manfred 
Published: November 2005

AbstractThe oxidative conversion of propane to acrylic acid and acetic acid over MoVSbRO (RLa, Ce, Nd and Sm) catalysts at different reaction conditions (viz. temperature, C3H8/O2 ratio, H2O/C3H8 ratio, space velocity, etc.) was investigated. The catalytic activity and selectivity of the MoVSb catalyst are strongly influenced by the addition of rare earth metals to the catalyst. The addition of water vapour to the feed of propane and oxygen enhances greatly the formation of oxygenated products, particularly acrylic acid and acetic acid. The ratio of selectivities of acrylic acid to acetic acid was found to depend on the rare earth metal used in the catalyst's preparation and the reaction conditions. High contact times, i.e. high degrees of propane conversion, are detrimental to the formation of acrylic acid but beneficial for acetic acid formation. Copyright © 2005 Society of Chemical Industry
Stable and efficient intraocular gene transfer using pseudotyped EIAV lentiviral vectors
Authors: Balaggan K. S. , Binley K. , Esapa M. , Iqball S. , Askham Z. , Kan O. , Tschernutter M. , Bainbridge J. W. B. , Naylor S. , Ali R. R. 
Published: November 2005

AbstractBackgroundWe have developed minimal non‐primate lentiviral vectors based on the equine infectious anaemia virus (EIAV). We evaluated the in vivo expression profiles of these vectors delivered regionally to ocular tissues to define their potential utility in ocular gene therapy.MethodsEIAV vectors pseudotyped with VSV‐G or rabies‐G envelope proteins were delivered subretinally, intravitreally or into the anterior chambers (intracameral administration) in mice. Reporter gene (eGFP) expression was analysed using in vivo retinal imaging or histological examination of eyes and brains at intervals between 3 days and 16 months. We investigated the effects of vector titre, pseudotype, genome configuration, site of intraocular administration, intentional retinal trauma and the degree of retinal maturation on the spatial and temporal expression profiles of these vectors.ResultsSubretinal vector delivery resulted in efficient and stable transduction of retinal pigment epithelial (RPE) cells and variable transduction of photoreceptors up to 16 months post‐injection. Retinal trauma facilitated the local transduction of neurosensory retinal cells. Intracameral administration of VSV‐G‐ but not rabies‐G‐pseudotyped vectors produced stable eGFP expression in corneal endothelial cells and trabecular meshwork.ConclusionsThe cellular tropism and expression kinetics of optimised EIAV vectors after intraocular administration make them attractive vehicles for delivering therapeutic genes in the management of inherited and acquired retinal and anterior segment disorders. Copyright © 2005 John Wiley & Sons, Ltd.
Thyroid hormone stimulates γ‐glutamyl transpeptidase in the developing rat cerebra and in astroglial cultures
Authors: Dasgupta Asmita , Das Sumantra , Sarkar Pranab Kumar 
Published: November 2005

AbstractHypothyroidism in the developing rat brain is associated with enhanced oxidative stress, one of the earliest manifestations of which is a decline in the level of glutathione (GSH). To investigate the role of thyroid hormone (TH) on GSH homeostasis, the effect of TH on γ‐glutamyl transpeptidase (γGT), the key enzyme involved in the catalysis of GSH, was studied. Hypothyroidism declined the specific activity of cerebral γGT at all postnatal ages examined (postnatal day 1–20) with a maximum inhibition of 42% at postnatal day 10. Intraperitoneal injection of TH to 15‐day‐old rat pups increased the specific activity of γGT by 25‐30% within 4–6 hr. Treatment of primary cultures of astrocytes by TH also enhanced the specific activity of γGT by 30–40% within 4–6 hr. The induction of γGT by TH was blocked by actinomycin D or cycloheximide. γGT is an ectoenzyme that is normally involved in the catabolism of GSH released by astrocytes. In the presence of the γGT‐inhibitor, acivicin, GSH released in the culture medium of astrocytes increased linearly for at least 6 hr and TH had no effect on this accumulation pattern. In the absence of acivicin, GSH content of the medium from TH‐treated cells was significantly lower than that of untreated controls due to activation of γGT by TH and a faster processing of GSH. Because the products of γGT reaction are putative precursors for neuronal GSH, the activation of γGT by TH may be conducive to GSH synthesis in neurons and their protection from oxidative stress. © 2005 Wiley‐Liss, Inc.
Biodegradable Hyaluronic Acid/N‐Carboxyethyl Chitosan/Protein Ternary Complexes as Implantable Carriers for Controlled Protein Release
Authors: Jiang Hongliang , Wang Yijuan , Huang Qian , Li Yan , Xu Chaonan , Zhu Kangjie , Chen Weiliam 
Published: November 2005

AbstractSummary: An ampholytic N‐carboxyethyl chitosan (CEC), with various isoelectric points (IPs), was synthesized by grafting acrylic acid on chitosan utilizing Michael's reaction. Compared to native chitosan, CEC has enhanced water solubility and dramatically accelerated enzymatic degradation; the rate of degradation is proportional to the degree of substitution (DS). The results from turbidimetric titration and fluorescence studies revealed that CEC formed complexes with either hyaluronic acid (HA) or bovine serum albumin (BSA) within a certain pH range. The HA/CEC/BSA ternary complexes could be prepared by colloid titration with quantitative yield and BSA entrapment. The rate of BSA release from the complexes was affected by pH, ionic strength, DS of CEC, and the molecular weight (MW) of HA. The endurance of BSA release from the complexes could be extended up to 20 d by formulating them with high‐MW HA and CEC with low DS.BSA release profiles from HA/CEC‐2/BSA complexes.magnified imageBSA release profiles from HA/CEC‐2/BSA complexes.
Relationship Between Architecture and Adhesion in Polyurethane‐Based Copolymers, 2
Authors: Baron Amélie , Rodriguez‐Hernandez Juan , Papon Eric 
Published: November 2005

AbstractSummary: This study describes the chain extension, with polycaprolactone diols, of polyurethane‐graft‐poly(butyl acrylate)s which were first prepared by the step growth polymerization of a mixture of diphenylmethane‐4,4′‐diisocyanate (MDI) and α,α′‐dihydroxyl‐poly(butyl acrylate)s. The success of the chain extension reaction was studied and confirmed by 1H NMR, SEC and DSC analysis. The incorporation of polycaprolactone sequences in the polyurethane chains modified their specific adhesive properties, bringing cohesion to the material, as demonstrated by tack measurements.PUR‐graft‐PBA extended with PCL.magnified imagePUR‐graft‐PBA extended with PCL.
Resistivity and Thermal Reproducibility of the Carbon Black and SnO2/Sb Coated Titanium Dioxide Filled Silicone Rubber Heaters
Authors: Park Eun‐Soo 
Published: November 2005

AbstractSummary: Flexible heaters were prepared by extruding platinum‐catalyzed silicone rubber compound with electroconductive carbon black (CB) and SnO2/Sb coated titanium dioxide (TiO2). Two types of acicular‐shaped TiO2 with average particle sizes of 1.7 and 5.2 µm, and two types of spherical‐shaped TiO2 with average particle sizes of 0.3 and 2.5 µm were selected. Thermoelectric switching phenomena were investigated for the silicone rubber/CB/TiO2 system. Positive temperature coefficient (PTC) was significant when the acicular filler was added rather than spherical ones. Resistivity change and thermal reproducibility of the extruded heaters were also investigated by applying periodically AC voltage of 220 V. The heaters containing acicular‐shaped TiO2 exhibited excellent electrical reproducibility.Scanning electron micrograph of the fractured surface of the extruded composites.magnified imageScanning electron micrograph of the fractured surface of the extruded composites.
FT‐IR Study of Blends and Complexes of Poly(mono n‐alkyl itaconates) with Poly(N,N‐dimethylacrylamide) and Poly(ethyloxazoline)
Authors: Meaurio Emilio , Katime Issa 
Published: November 2005

AbstractSummary: This paper reports an FT‐IR study of blends and complexes of poly(mono n‐alkyl itaconates) with poly(N,N‐dimethylacrylamide) (PDMA) and poly(ethyloxazoline) (PEOX). Strong hydrogen bonding has been found and both polybases have shown similar acceptor strengths. The extent of the interassociation has been estimated by spectral curve fitting of the polybase carbonyl band. The influences of the solvent medium and alkyl side group length of the poly(mono n‐alkyl itaconate) on the interassociation extents have been discussed. Blend and complex interassociation behavior has been compared too. Results show that media influences the interassociation degree in systems with PDMA, but has negligible influence in systems with PEOX. Moreover, the interassociation degree in blends with PEOX does not depend on the length of the poly(monoalkyl itaconate) side group, while an interassociating ability loss is observed in blends with PDMA as the side group size of the polyacid increases. This different behavior is attributed to the greater interspacing between vicinal carbonyl groups in PEOX. Anyway, this band shows conformational sensitivity and reflects the conformational changes that are forced to adopt as the steric hindrances present in the medium (due to the bulky side groups of the polyacids) increase.Auto scaled carbonyl stretching region for PMBuI/PEOX complexes.magnified imageAuto scaled carbonyl stretching region for PMBuI/PEOX complexes.