bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Homogeneously Alloyed Cu2−x(SySe1−y) Nanowire Bundles with Tunable Compositions and Bandgaps
Authors: Xu Jun , Tang Yong‐Bing , Chen Xue , Luan Chun‐Yan , Zhang Wen‐Feng , Zapien Juan Antonio , Zhang Wen‐Jun , Kwong Hoi‐Lun , Meng Xiang‐Min , Lee Shuit‐Tong , Lee Chun‐Sing 
Published: September 2010

AbstractBundles of homogeneously alloyed Cu2−x(SySe1−y) nanowires with various compositions (0 ≤ y ≤ 1) are controllably prepared via a simple water‐evaporation method under mild conditions. It is found that the nanowire bundles have similar copper contents (0.37 ≤ x ≤ 0.44) and morphologies, and the same face centered cubic (fcc) crystal structure and growth orientation of [110] over the entire composition range of y. To the best of the authors' knowledge, this is the first report on cubic phased ternary Cu2−x(SySe1−y) compounds. It is found that lattice parameter of the Cu2−x(SySe1−y) compound changes linearly with the S content. It is also shown that the direct and the indirect bandgaps of the nanowires vary quadratically with the S content and have bowing parameters of 0.20 and 0.21 eV respectively. Energy‐gap‐tuning via compositional change is achieved for both the direct (1.48−1.87 eV) and the indirect (0.50−0.90 eV) bandgaps. The trends of lattice parameter and bandgap variations are consistent with those described by Végard's Law.
Tailoring the Electrical Properties of Carbon Nanotube–Polymer Composites
Authors: Huang Yan Y. , Terentjev Eugene M. 
Published: September 2010

AbstractAdvances in functionality and reliability of nanocomposite materials require careful formulation of processing methods to ultimately realize the desired properties. An extensive study of how the variation in fabrication process would affect the mechanism of conductivity and thus the final electrical properties of the carbon nanotube–polymer composite is presented. Some of the most widely implemented procedures are addressed, such as ultrasonication, melt shear mixing, and addition of surfactants. It is hoped that this study could provide a systematic guide to selecting and designing the downstream processing of carbon nanocomposites. Finally, this guide is used to demonstrate the fabrication and performance of a stretchable (pliable) conductor that can reversibly undergo uniaxial strain of over 100%, and other key applications are discussed.
Ultrasensitive and Highly Selective Gas Sensors Based on Electrospun SnO2 Nanofibers Modified by Pd Loading
Authors: Yang Dae‐Jin , Kamienchick Itai , Youn Doo Young , Rothschild Avner , Kim Il‐Doo 
Published: September 2010

AbstractThis work presents a new route to suppress grain growth and tune the sensitivity and selectivity of nanocrystalline SnO2 fibers. Unloaded and Pd‐loaded SnO2 nanofiber mats are synthesized by electrospinning followed by hot‐pressing at 80 °C and calcination at 450 or 600 °C. The chemical composition and microstructure evolution as a function of Pd‐loading and calcination temperature are examined using EDS, XPS, XRD, SEM, and HRTEM. Highly porous fibrillar morphology with nanocrystalline fibers comprising SnO2 crystallites decorated with tiny PdO crystallites is observed. The grain size of the SnO2 crystallites in the layers that are calcined at 600 °C decreases with increasing Pd concentration from about 15 nm in the unloaded specimen to about 7 nm in the 40 mol% Pd‐loaded specimen, indicating that Pd‐loading could effectively suppress the SnO2 grain growth during the calcination step. The Pd‐loaded SnO2 sensors have 4 orders of magnitude higher resistivity and exhibit significantly enhanced sensitivity to H2 and lower sensitivity to NO2 compared to their unloaded counterparts. These observations are attributed to enhanced electron depletion at the surface of the PdO‐decorated SnO2 crystallites and catalytic effect of PdO in promoting the oxidation of H2 into H2O. These phenomena appear to have a much larger effect on the sensitivity of the Pd‐loaded sensors than the reduction in grain size.
Simple Chiral Diaminobinaphthyl Dilithium Salts for Intramolecular Catalytic Asymmetric Hydroamination of Amino‐1,3‐dienes
Authors: Deschamp Julia , Olier Clarisse , Schulz Emmanuelle , Guillot Régis , Hannedouche Jérôme , Collin Jacqueline 
Published: September 2010

AbstractSimple and easily accessible chiral lithium amide salts are reported as efficient (pre)catalysts for the diastereo‐ [up to (E:Z)=92:8] and enantioselective [up to 72% ee (E)] hydroamination/cyclisation of conjugated primary aminodienes. These chiral lithium salts are straightforwardly prepared by in situ combination of an N‐substituted (R)‐(+)‐1,1′‐binaphthyl‐2,2′‐diamine ligand and a commercial methyllithium solution. Information on the solid‐state structure of these salts was obtained by X‐ray analysis of a single crystal.
Selective Synthesis of 1,4‐Dialkylbenzenes from Terephthalic Acid
Authors: Bramborg Andrea , Linker Torsten 
Published: September 2010

AbstractTerephthalic acid reacts with alkyl halides under Birch conditions to substituted 1,4‐cyclohexadienes in high yields and good stereoselectivities. Electrophiles containing ester or nitrile groups undergo a surprising fragmentation under the reaction conditions. Subsequent treatment with chlorosulfonic acid proceeds by an interesting tandem decarbonylation/decarboxylation, affording 1,4‐dialkylbenzenes in excellent regioselectivity. Thus our new method is superior to classical Friedel–Crafts alkylations.
New Platinum‐Catalysed Dihydroalkoxylation of Allenes
Authors: Paz Muñoz María , de la Torre María C. , Sierra Miguel A. 
Published: September 2010

AbstractA new platinum‐catalysed dihydroalkoxylation of allenes is described to give aliphatic acetals by an unexpected attack of two molecules of methanol to the terminal carbon of the allene moiety. Deuteration experiments suggest an unprecedented formal 1,3‐dipolar addition of methanol to a zwitterionic platinum carbene as the key step. The first platinum‐catalysed intermolecular carbon‐based nucleophile addition to allenes is also reported.
Evaluation of Electron‐Deficient Phosphine Ligands for Direct Arylation of Heterocycles
Authors: René Olivier , Fagnou Keith 
Published: September 2010

AbstractNew electron‐deficient biarylphosphine ligands were studied and proved to be efficient for the direct arylation of heteroarenes with aryl iodides. The ability of a more electron‐deficient palladium centre to accelerate the arylation of heterocycles that remained unreactive with aryl iodides in the past has been validated and these heteroarenes can now be smoothly reacted in the presence of a new electrophilic catalyst. Experimental evidence suggests a viable concerted metalation–deprotonation pathway for the CH bond cleavage step with an electron‐deficient palladium centre.
Low‐Pressure Hydrogenation of Arenecarboxylic Acids to Aryl Aldehydes
Authors: Gooßen Lukas J. , Khan Bilal Ahmad , Fett Thomas , Treu Matthias 
Published: September 2010

AbstractA highly effective palladium catalyst has been developed that allows the selective hydrogenation of arenecarboxylic acids to the aryl aldehydes in the presence of pivalic anhydride already at 5 bar hydrogen pressure. With the new catalyst, diversely functionalized aromatic and heteroaromatic aldehydes are conveniently accessible from the corresponding carboxylic acids in a single reaction step without any overreduction to the alcohols.
Counter‐intuitive temperature excursions during regeneration of a diesel particulate filter
Authors: Chen K. , Martirosyan K. S. , Luss D. 
Published: September 2010

AbstractA major technological challenge in the regeneration of diesel particulate filters (DPFs) is that sometimes local high temperature excursions melt the cordierite ceramic filter. The cause of this melting is still an open question as the highest temperature attained under stationary (constant feed) combustion of the accumulated particulate matter is too low to cause this melting (melting temperature ∼1250°C). We recently conjectured that the high temperature excursions are a counterintuitive response to a rapid deceleration, which decreases the exhaust gas temperature and flow rate and increases the oxygen concentration. Infrared measurements of the spatiotemporal temperature during soot combustion on a single‐layer DPF showed that a simultaneous step change of the feed temperature, flow rate, and oxygen concentration can lead to a transient temperature that exceeds the highest attained for stationary operation under either the initial or the final operation conditions. The experiments revealed that the magnitude of the temperature rise depends in a complex way on several factors, such as the direction of movement of the propagating temperature front. The amplitude of the temperature rise is a monotonic decreasing function of the distance that the temperature front moved before the step change. The rapid response to the feed oxygen concentration increases initially the moving front temperature. The slow response of the ceramic DPF to a decrease in the feed temperature may eventually decrease the moving front temperature and even lead to premature extinction and partial regeneration. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Improved performance of simulated moving bed process using column‐modified feed
Authors: Lee Hyeon‐Hui , Kim Kyung‐Min , Lee Chang‐Ha 
Published: September 2010

AbstractA “FeedCol” strategy was developed to improve separation performance in simulated moving bed (SMB) processes. In the FeedCol operation, a short chromatographic column was simply added to the SMB unit and feed was supplied by a pulse input through the column to the SMB process. Because the feed was made in the shape of partially separated chromatographic peaks through the column, the purities in the raffinate and extract products were improved efficiently in the SMB process. All the performance parameters for a binary mixture with low selectivity (α = 1.1) were better for the FeedCol operation than for the conventional SMB operation (2‐2‐2‐2). Because the feed injection through the feed column was synchronized with the SMB process during the switching period, two new operating variables were introduced: injection length and injection time. Their effects on the suggested strategy were evaluated in terms of performance parameters through a detailed simulation study. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Heterocyclic synthesis with isothiocyantes: Synthesis of several new polyfunctionally substituted thiophene, Δ4‐thiazoline and thiazolidinone derivatives
Authors: Mohareb Rafat Milad , Sherif Sherif Mourad 
Published: September 2010

AbstractFacile unequivocal syntheses of the title compounds are reported via “in situ” cyclization of the non‐isolable adducts 2a‐d with α‐halogenated electrophilic compounds. Chemical and spectroscopic evidences for the structures of the new compounds are described.
Synthese Von β‐Aryl‐Methotrexat Derivaten
Authors: Sin Kwan Seog , Sung Sun Young , Kim Kyeong Ho , Lee Chang Kiu , Jun Jong Gap , Pachaly Peter 
Published: September 2010

AbstractEs wird über die Synthese einer Reihe neuer Methotrexatanaloga berichtet, in denen die β‐Position des Clutaminsäureteils zur Erhöhung der lipophilen Eigenschaften arylsubstituiert ist. Ausgehend von trans‐3‐Aryl‐2‐carboxy‐5‐pyrrolidon‐Derivaten werden die daraus durch Hydrolyse erhaltenen β‐Arylglutaminsäuren mit dem p‐Aminobenzoesäureteil und dem Pteridinteil zu β‐Aryl‐methotrexatderivaten umgesetzt, die möglicherweise als cytostatisch und bacterizid wirksame Verbindungen Bedeutung erlangen könnten.
Methoxy‐ and acetoxy‐8‐oxoberbines ‐ synthesis, antitumor activity, and interaction with DNA
Authors: Weimar Christian , Angerer Silvia Von , Wiegrebe Wolfgang 
Published: September 2010

AbstractMost of the methoxy‐8H‐dibenzo[a,g]isoquinolin‐8‐ones 3a‐h and their acetoxy derivatives 6a‐e were synthesized by condensation of 1‐oxo‐1,2,3,4‐tetrahydroisoquinolines 4a‐c and homophthalic acid anhydrides 5a and b, ether cleavage and acetylation. These protoberberinones were tested for cytostatic activityin vitrousing MDA‐MB‐231 mammary tumor cells and for interaction with native calf thymus DNA. Tetramethoxy‐8‐oxoberbine 3f shows an inhibition of cell proliferation of 87% at a concentration of 10−5mole; its cytostatic effect does not depend on intercalation into DNA.
Cu(II) complex of an estradiol derivative with potent anti‐inflammatory properties
Authors: Spyriounis Dimitris M. , Rekka Eleni , Demopoulos Vassilis J. , Kourounakis Panos N. 
Published: September 2010

AbstractIn the present study, the A‐ring of estradiol was converted to an acetylsalicylic structure which was further complexed with Cu(II). The aim was to combine the anti‐inflammatory properties of estrogens with those of Cu(II) complexes. Key intermediate of the synthesis was 2‐formyl‐estradiol (2) which was prepared in quantitative yield through reaction of the phenoxymagnesium bromide of estradiol with formaldehyde in the presence of HMPA. For a successful reaction, an excess of ethylmagnesium bromide was required, and the mechanism is discussed. The target complex 5 exhibited potent anti‐inflammatory properties, comparable to those of indomethacin, in the carrageenan‐induced rat paw edema. This biological activity was not due either to the steroidal ligand or to the complexed Cu(II) alone.
1,4‐pentandien‐3‐ones, XXXII: Reaction of 2‐acetylthiophene and 2‐acetylfuran with malononitrile and aldehydes, and synthesis and properties of phenylene‐bis [(thienyl/furyl)nicotinonitrile] derivative
Authors: Greiner‐Bechert Lutz , Otto Hans‐Hartwig 
Published: September 2010

AbstractThe (E)‐1‐hetaryl‐2‐propen‐1‐ones 3 and 4 are prepared by condensation of 2‐acetylthiophenes (1a,1c,1d) or 2‐acetylfuran (1b) with aldehydes. The Michael adducts 5/6 are obtained from 3/4 by reaction with malononitrile/LDA in THF at −78°C, or in DMSO with NaH at room temp. Reaction of 3/4 with malononitrile and methylate in methanol yielded the substituted nicotinonitriles 7/8. From terephthalaldehyde, the diketones 9 are prepared, which yield with malononitrile the phenylene‐bis[(thienyl/furyl)nicotinonitrile] derivatives 10 under similiar conditions. Structural and spectral data are discussed.
Acute toxicity of amine‐boranes and related derivatives in mice
Authors: Hall Iris H. , Reynolds David J. , Chang J. , Spielvogel Bernard F. , Griffin T.S. , Docks E.L. 
Published: September 2010

AbstractThree boron derivatives,i.e.trimethylamine‐carbomethoxyborane, tetrakis‐μ‐(trimethylamine‐boranecarboxylato)‐bis(trimethylamine‐carboxyborane)‐dicopper(II), andN,N‐dimethyl‐n‐octadecylamine borane were evaluated for acute toxicity in male mice, at 1, 2 or 5 x their therapeutic dose in rodents for pharmacological activity. Based on organ weights, clinical chemistry, hematopoietic parameters and tissue morphology, the trimethylamine‐carbomethoxyborane was shown to be free of toxicity. The dicopper(II) complex andN,N‐dimethyl‐n‐octadecylamine borane demonstrated slight toxicity with marginal disturbance in hepatic and kidney morphology. The dicopper(II) complex may cause marginal myocardial damage and theN,N‐dimethyl‐n‐octadecylamine borane caused elevations in cholic acid. All three derivatives demonstrated reductions in hematocrit.
6,7‐Dihydro‐4H‐indolones: Synthesis and biological properties
Authors: Schiller Claus‐D. , Angerer Erwin Von , Schneider Martin R. 
Published: September 2010

AbstractSyntheses of 6,7‐dihydro‐4H‐indolones 6 and 10 by a selective Birch reduction of the benzene ring of the indole system are described. The antiestrogen zindoxifene and the 2‐phenylindole 2 as well as 6 and 10 were tested for their relative binding affinities at the androgen receptor as well as for antiandrogenic and estrogenic properties. Both compounds 6 and 10 showed potent indirect antiandrogenic activity which were similar to those of the 2‐phenyl‐indoles zindoxifene and 2.
Free‐radical synthesis of 3‐(2‐cyanoethyl)‐ and 3‐(2‐methoxycarbonylethyl)‐2,3‐dideoxy‐α‐D‐Erythro‐pentofuranoside and their application in the synthesis of potential antiviral nucleosides
Authors: Lau Jesper , Walczak Krzysztof , Pupek Krzysztof , Buch Carsten , Nielsen Carsten M. , Pedersen Erik B. 
Published: September 2010

AbstractFree‐radical reaction of different carbohydrate educts 2, 5, and 7 with acrylonitrile in the presence of tributyltin hydride and a radical initiator (AIBN) gave the methyl 3‐(2‐cyanoethyl)‐2,3‐dideoxypentofuranosides 3a and 6. Similar reaction of 2 with methyl acrylate gave 3‐(2‐methoxycarbonylethyl>‐2,3‐dideoxypentofuranose 3b. Nucleoside coupling of 3a with silylated uracil gave an anomeric mixture of β‐ and α‐nucleoside 8 and 9 which were deprotected to give 10 and 11, respectively. Similar reaction of 3b with silylated N4‐isobutyrylcytosine gave 12 and 13 which were deprotected to give the final nucleosides 16 and 17, respectively. None of the compounds 10a, 11, 14‐17 showed significant activity against HIV.
Synthese heterocyclischer immunmodulatoren, 1. Mitt.: Alkylderivate von 1,2,4‐Dithiazolidin‐3,5‐Diyliden‐Bis(O‐Benzochinonmethid): Synthese und Prüfung Auf Immunmodulierende Wirkung
Authors: Briel Detlef , Leistner Siegfried , Drößler Karl 
Published: September 2010

AbstractDie Reaktion des 1,2,4‐Dithiazolidin‐3,5‐diyliden‐bis(o‐benzochinonmethids) 3 mit Alkylhalogeniden bzw. substituierten Benzyl‐ oder Phenacylhalogeniden führt zu den 1,2,4‐Dithiazol‐3‐yliden‐chinonmethiden 4a‐4l. Die ms‐Fragmentierung von 4a, 4c und 4f wird diskutiert Die Prüfung von 4a‐c, 4e und 4g auf immunmodulierende Wirkung wird beschrieben; einige dieser Verbindungen zeigen immunstimulierende Effekte.
Alcohol consumption and markers of inflammation in women with preclinical rheumatoid arthritis
Authors: Lu Bing , Solomon Daniel H. , Costenbader Karen H. , Keenan Brendan T. , Chibnik Lori B. , Karlson Elizabeth W. 
Published: September 2010

AbstractObjectiveTo examine the association between alcohol consumption and markers of inflammation in preclinical rheumatoid arthritis (RA).MethodsWe studied 174 incident RA cases with stored blood collected 1–16 years prior to RA symptoms (preclinical RA), from the Nurses' Health Study. Alcohol intake was measured using a detailed food frequency questionnaire administered every 4 years, prior to blood collection. Plasma was tested for biomarkers of inflammation, including high‐sensitivity C‐reactive protein (hsCRP), anti–cyclic citrullinated peptide (anti‐CCP) antibodies, interleukin‐6 (IL‐6), and soluble tumor necrosis factor receptor II (sTNFRII). Generalized additive models were used to identify structure in the relationship between each biomarker and cumulative average alcohol intake. Then general linear models were used for multivariable adjusted analyses with appropriate polynomial terms of alcohol consumption.ResultsAfter controlling for age at blood collection, smoking, parity and duration of breastfeeding, menopausal status, oral contraceptive use, body mass index, and the time between blood collection and RA onset, we found that the daily alcohol consumption showed a U‐shaped association with IL‐6 levels in RA patients, prior to symptoms. We also found an inverse relationship between alcohol intake and sTNFRII levels, but no associations with hsCRP or anti‐CCP levels.ConclusionThese results demonstrate an association between alcohol consumption and markers of inflammation, including IL‐6 and sTNFRII, in RA patients, prior to the occurrence of symptoms.
Juvenile idiopathic arthritis and risk of cancer: A nationwide cohort study
Authors: Simard J. F. , Neovius M. , Hagelberg S. , Askling J. 
Published: September 2010

AbstractObjectiveReports of therapy‐related adverse events suggest an elevated rate of malignancy in patients with juvenile idiopathic arthritis (JIA) treated with biologic therapies. However, the scarcity of data on the underlying risk of malignancy in JIA hampers interpretation of these signals. Therefore, the aim of this study was to determine the risk of cancer in patients with JIA as compared with that in the general population.MethodsThrough linkage with a national database, the Swedish Patient Register (comprising inpatient discharges in 1969–2007 and specialist outpatient visits in 2001–2007 in Sweden), a national JIA cohort (n = 9,027) was identified, and each JIA case was matched with 5 general population comparators. Using data from the Swedish Cancer, Census, Death, and Biologics Registers, the occurrence of cancer, vital status, and start of a biologic therapy were identified. The relative risk (RR) of first occurrence of a primary cancer in patients who had not been treated with biologics (biologics‐naive patients with JIA) was estimated using Poisson regression, stratified a priori by year of earliest identification of JIA (before 1987 versus 1987 and thereafter). In sensitivity analyses, the data were followed up to 1999, when biologics first became available.ResultsIn this biologics‐naive JIA cohort, 60 malignancies were observed during 131,144 person‐years of followup, compared with 266 cancers observed during 661,758 person‐years in the general population comparator (0.46 cases/1,000 person‐years versus 0.40 cases/1,000 person‐years; RR 1.1, 95% confidence interval [95% CI] 0.9–1.5). Patients with JIA identified before 1987 were not at increased risk of cancer, whereas JIA identified in 1987 and thereafter was significantly associated with incident lymphoproliferative malignancies (RR 4.2, 95% CI 1.7–10.7) and cancers overall (RR 2.3, 95% CI 1.2–4.4). Sensitivity analyses did not reveal any ready explanation for this heterogeneity.ConclusionAlthough absolute risks were low, an elevated risk of malignancy was observed among biologics‐naive patients in whom the diagnosis of JIA was made in the past 20 years, which may have implications for the interpretation of cancer signals in patients with JIA treated with newer therapies.
Effects of lovastatin on the pharmacokinetics of nicardipine in rats
Authors: Chung Joong‐W. , Yang Si H. , Choi Jun‐S. 
Published: September 2010

AbstractIt has been reported that both nicardipine and lovastatin are substrates of both the cytochrome P450 (CYP) 3A subfamily and P‐glycoprotein (P‐gp), and P‐gp transport is unlikely to be a significant factor. Thus, the effects of oral lovastatin on the pharmacokinetics of intravenous and oral nicardipine were investigated in rats. Nicardipine was administered intravenously (4 mg/kg) and orally (12 mg/kg) with 0 (control), 0.3 and 1 mg/kg of oral lovastatin to rats. Lovastatin was administered 30 min before nicardipine administration. After intravenous administration of nicardipine with 0, 0.3 and 1  mg/kg of lovastatin, the total areas under the plasma concentration–time curve from time zero to infinity (AUCs) of nicardipine were not changed by lovastatin. However, after oral administration of nicardipine with 1 mg/kg of oral lovastatin, the AUC of nicardipine was significantly greater (by 67.4%), and the extent of absolute oral bioavailability (F) of nicardipine was increased (by 38.5%). The above data suggest that lovastatin did not considerably inhibit the metabolism of nicardipine via the hepatic CYP3A subfamily, but inhibited intestinal P‐gp and/or the CYP3A subfamily. Copyright © 2010 John Wiley & Sons, Ltd.