bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution to the study of binaries with spectral types F, G, K, and M – XI. Orbital elements of three red‐giant spectroscopic binaries: HR 1304, HR 1908, and HD 126947
Authors: Prieur J.‐L. , Carquillat J.‐M. , Griffin R. F.
Published: July 2006

The orbital elements of three red‐giant single‐lined spectroscopic binaries, HR 1304, HR 1908 and HD 126947, are presented. They are obtained from observations made with two photoelectric spectrometers of CORAVEL type, the first located at the Observatoire de Haute‐Provence and the second at the Cambridge Observatories. HR 1304 and HR 1908 are known to be chromospherically active stars and to have high spatial velocities; HD 126947 is an intrinsic variable newly detected by Hipparcos. The three systems have long orbital periods: 1.9, 3.2 and 7.7 yr for HR 1304, HR 1908 and HD 126947, respectively. From the orbital elements that we determined and other data available in the literature, we deduce some information about the unseen companions and their separations with respect to the primaries. Finally we discuss the rotation–revolution synchronism and conclude that one star, HR 1908, may have reached the state of pseudo‐synchronism, despite of its long orbital period. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Advection‐dominated solar dynamo model with two‐cell meridional flow and a positive α ‐effect in the tachocline
Authors: Bonanno A. , Elstner D. , Belvedere G.
Published: July 2006

Most probably the sunspot cycle period is ruled by a meridional flow located near the base of the convection zone (Hathaway et al. 2003). On the other hand, if the eddy diffusivity is low enough, dramatic modification of the standard α 2Ω ‐dynamo by the meridional flow are expected. In this paper we shall discuss the dependence of periods, dynamo numbers and the sign of the current helicity as a function of the magnetic Reynolds number for a double cell meridional circulation and for a positive α ‐effect at the base of the convection zone. The dynamo action occurs at lower latitudes and its location is at the interface between equatorward and poleward motions near the base of the convection zone. In spite of the complexity of the flow pattern, our simulations show that the resulting dynamo action reproduces several observed features of the solar cycle. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental and Theoretical Characterization of the Valence Isomerization of Bi‐2H‐azirin‐2‐yls to Diazabenzenes
Authors: Banert Klaus , Grimme Stefan , Herges Rainer , Heß Kirsten , Köhler Frank , Mück‐Lichtenfeld Christian , Würthwein Ernst‐Ulrich
Published: July 2006

3,4‐Diazidocyclobutenes 16 were prepared from the corresponding dihalides. Some of these diazides, such as parent compound 16 d and phenyl‐substituted derivatives 16 c,f, underwent spontaneous stereoselective electrocyclic ring opening below room temperature, whereas the tetraalkyl derivatives of 16 had to be heated to force the same reaction. In most cases, the resulting 1,4‐diazidobuta‐1,3‐dienes 8 were isolated to study their photochemical transformation into bi‐2H‐azirin‐2‐yls 9 via intermediate mono‐azirines 17. Except for starting materials with a low number of substituents such as 9 d and 9 f, title compounds 9 underwent a thermal valence isomerization which led exclusively to pyridazines 18 at surprisingly low temperatures. Based on quantum‐chemical calculations for the parent bi‐2H‐azirinyl‐2‐yl 9 d at the UB3LYP/6‐31+G(d) and MR‐MP2/TZV(2df,2p) levels, the valence isomerization process is best explained by simultaneous homolytic cleavage of both CN single bonds of 9 to generate energetically favorable N,N′ diradicals 26, which cyclize to 18. The theoretical studies indicate also that one stereoisomer of 9, namely, the rac compound, should undergo valence isomerization more easily than the other, which is in conformity with different rates of these rearrangement reactions found experimentally. For the tetramethyl‐bi‐2H‐azirin‐2‐yls 9 g, which are better models for the experimentally studied compounds, simultaneous homolytic cleavage of both CN single bonds is also predicted by the calculations, although the intermediate diradicals 26 g are significantly higher in energy than those of the parent system 9 d.
Ab initio Structure Determination of Novel Borate NaSrBO3.
Authors: Wu L. , Chen X. L. , Zhang Y. , Kong Y. F. , Xu J. J. , Xu Y. P.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structures and Bonding in K0.91U1.79S6 and KU2Se6.
Authors: Mizoguchi Hiroshi , Gray Danielle , Huang Fu Qiang , Ibers James A.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
7Li NMR and Two‐Dimensional Exchange Study of Lithium Dynamics in Monoclinic Li3V2(PO4)3.
Authors: Cahill L. S. , Chapman R. P. , Britten J. F. , Goward G. R.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Molecular Dynamics Study of the Thermal Entropy in Mixed Zinc Chalcogenides
Authors: Jug Karl , Nair Nisanth N. , Gloriozov Igor P.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cleavage of the N2 Triple Bond by the Ti Dimer: A Route to Molecular Materials for Dinitrogen Activation?
Authors: Himmel Hans‐Joerg , Huebner Olaf , Klopper Wim , Manceron Laurent
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Unequivocal Heteroatom Insertion into a 24‐Ring Channel Gallophosphate and Its Photoluminescence.
Authors: Lin Chia‐Her , Yang Ya‐Ching , Chen Chun‐Yu , Wang Sue‐Lein
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Metal‐Free Catalytic Nucleophilic Substitution of Propargylic Alcohols.
Authors: Sanz Roberto , Martinez Alberto , Alvarez‐Gutierrez Julia M. , Rodriguez Felix
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Solvent‐Free Carbon—Oxygen Bond Formation Catalyzed by CeCl3×7H2O/NaI: Tetrahydropyranylation of Hydroxy Groups.
Authors: Bartoli Giuseppe , Giovannini Riccardo , Giuliani Arianna , Marcantoni Enrico , Massaccesi Massimo , Melchiorre Paolo , Paoletti Melissa , Sambri Letizia
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Air‐Stable, Phosphine‐Free Anionic Palladacyclopentadienyl Catalysts: Remarkable Halide and Pseudohalide Effects in Stille Coupling.
Authors: Crawforth Catherine M. , Fairlamb Ian J. S. , Kapdi Anant R. , Serrano Jose Luis , Taylor Richard J. K. , Sanchez Gregorio
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Mild and Efficient One‐Step Synthesis of Trithiocarbonates Using Minimum Amount of CS2.
Authors: Aoyagi Naoto , Ochiai Bungo , Mori Hideharu , Endo Takeshi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Direct Entry to Bicyclic Cyclobutenes via Platinum‐Catalyzed Cycloisomerization of Allenynes.
Authors: Matsuda Takanori , Kadowaki Sho , Goya Tsuyoshi , Murakami Masahiro
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cyclization/Acylation Reactions by Nickel‐Catalyzed Reactions of 1,6‐Ynal and 1,6‐Enyne Derivatives with Acylzirconocene Chloride.
Authors: Saito Akio , Oka Yusuke , Nozawa Yohei , Hanzawa Yuji
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Alkyne Metathesis: Toward Simplicity and Efficiency.
Authors: Maraval Valerie , Lepetit Christine , Caminade Anne‐Marie , Majoral Jean‐Pierre , Chauvin Remi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Simple, Convenient Method for the Synthesis of Maleic Anhydrides from α‐Keto Esters and Alkanoic Acid Anhydrides Using the TiCl4/n‐Bu3N Reagent System.
Authors: Kishorebabu Neela , Pariasamy Mariappan
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Facile and Stereoselective Synthesis of Unsymmetrical Diallylsulfides via Indium‐Promoted One‐Pot Reaction of Baylis—Hillman Acetates, Sodium Thiosulfate, and Allyl Bromide.
Authors: Liu Yunkui , Xu Xiangsheng , Zheng Hui , Xu Danqian , Xu Zhenyuan , Zhang Yongmin
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
An Iron‐Containing Ionic Liquid as Recyclable Catalyst for Aryl Grignard Cross‐Coupling of Alkyl Halides.
Authors: Bica Katharina , Gaertner Peter
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Regio‐ and Stereoselective Synthesis of Aziridino Epoxides from Cyclic Dienes.
Authors: Sureshkumar Devarajulu , Maity Susama , Chandrasekaran Srinivasan
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of 3‐Substituted Furans by Hydroformylation.
Authors: Nanayakkara Perli , Alper Howard
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Novel Reaction of Vicinal Tricarbonyl Compounds with the Isocyanide‐DMAD Zwitterion: Formation of Highly Substituted Furan Derivatives.
Authors: Nair Vijay , Deepthi Ani
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis, Anticonvulsant, and Antiinflammatory Activities of Some New Benzofuran‐Based Heterocycles.
Authors: Dawood Kamal M. , Abdel‐Gawad Hassan , Ellithey Mohey , Mohamed Hanan A. , Hegazi Bahira
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Catalyzed Cross‐Coupling Reactions of Heterocyclic Silanolates with Substituted Aryl Iodides and Bromides.
Authors: Denmark Scott E. , Baird John D.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Kinesin Spindel Protein (KSP) Inhibitors. Part 3. Synthesis and Evaluation of Phenolic 2,4‐Diaryl‐2,5‐dihydropyrroles with Reduced hERG Binding and Employment of a Phosphate Prodrug Strategy for Aqueous Solubility.
Authors: Garbaccio Robert M. , et al. et al.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Organocatalytic C3‐Selective Friedel—Crafts Alkylations of Indoles with α,β‐Unsaturated Ketones.
Authors: Li Dong‐Ping , Guo Ying‐Cen , Ding Yu , Xiao Wen‐Jing
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Structure of 4‐Indolyl‐5‐(thieno[3,2‐b]pyrrol‐6‐yl)imidazoles.
Authors: Krayushkin M. M. , Sedishev I. P. , Yarovenko V. N. , Zavarzin I. V. , Vorontsova L. G. , Starikova Z. A. , Nabatov B. V.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Rapid and Efficient Synthesis of 2‐Imidazolines and Bis‐imidazolines under Ultrasonic Irradiation.
Authors: Mirkhani Valiollah , Moghadam Majid , Tangestaninejad Shahram , Kargar Hadi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Benzoxazole Benzenesulfonamides as Allosteric Inhibitors of Fructose‐1,6‐bisphosphatase.
Authors: Lai Chunqiu , Gum Rebecca J. , Daly Melissa , Fry Elizabeth H. , Hutchins Charles , Abad‐Zapatero Celerino , von Geldern Thomas W.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Microwave Assisted Rapid and Efficient Synthesis of 2,1‐Benzoisoxazoles.
Authors: Rajanarendar E. , Rao E. Kalyan , Karunakar D.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Tyrosinase Inhibitory Kojic Acid Derivative.
Authors: Lee Yong Sup , Park Jang Hyun , Kim Min Hwan , Seo Seon Hee , Kim Hyoung Ja
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Catalyzed Cross‐Coupling Reactions of (2‐Pyridyl)allyldimethylsilanes with Aryl Iodides.
Authors: Nokami Toshiki , Tomida Yutaka , Kamei Toshiyuki , Itami Kenichiro , Yoshida Jun‐ichi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Tandem Claisen Rearrangement and Ruthenium‐Catalyzed Enyne Bond Reorganization as a Route to the Synthesis of Tricyclic 1,8‐Naphthyridinones.
Authors: Majumdar K. C. , Rahaman H. , Islam R. , Roy B.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Fluorine‐Containing 2‐(1‐Aryl‐4‐oxo‐1,4‐dihydrocinnolin‐3‐yl)‐2‐oxoacetic Acids.
Authors: Fokin A. S. , Burgart Ya. V. , Saloutin V. I. , Chupakhin O. N.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Tricyclic Purine Analogues Derived from 2‐Amino‐6‐chloropurine and 2,6‐Diaminopurine and Their Methylated Quaternary Salts.
Authors: Horejsi Katerina , Pohl Radek , Holy Antonin
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ring‐Chain Transformations of Dihydroisoxazolo[4,5‐b]quinoxaline.
Authors: Boguslavskii A. M. , Ponizovskii M. G. , Kodess M. I. , Charushin V. N.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Highly Substituted Enantiopure Piperazines and Ketopiperazines from Vicinal N‐Sulfinyl Diamines.
Authors: Viso Alma , Fernandez de la Pradilla Roberto , Flores Aida , Garcia Ana , Tortosa Mariola , Lopez‐Rodriguez Maria L.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of New Hexahydro‐ and Octahydropyrido[1,2‐c]pyrimidine Derivatives with an Arylpiperazine Moiety as Ligands for 5‐HT1A and 5‐HT2A Receptors. Part 4.
Authors: Herold Franciszek , Krol Marek , Kleps Jerzy , Nowak Gabriel
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
New Terpenoids from Amentotaxus formosana.
Authors: Chen Hui‐Ling , Wang Li‐Wen , Su Huey‐Jen , Wei Bai‐Luh , Yang Sheng‐Zehn , Lin Chun‐Nan
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthetic Approaches to Physiologically Active Polycyclic Compounds. Part 6. Synthesis of 1‐[(2R,3S)‐N‐Benzoylphenylisoseryloxy]‐4,4‐dimethyladamantane.
Authors: Zefirova O. N. , Nurieva E. V. , Zyk N. V.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Brief Total Synthesis of Fumaramidine.
Authors: Lamblin Marc , Couture Axel , Deniau Eric , Grandclaudon Pierre
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Mechanochemical Preparation of Molecular and Supramolecular Organometallic Materials and Coordination Networks
Authors: Braga Dario , Giaffreda Stefano L. , Grepioni Fabrizia , Pettersen Anna , Maini Lucia , Curzi Marco , Polito Marco
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Introduction of Metal‐Coordination Polymers
Authors: Carraher, Charles E. Jr. , Pittman, Charles U. Jr. , Abd‐El‐Aziz Alaa S.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Chromium—Arene Complexes
Authors: Schmalz Hans‐Guenther , Dehmel Florian
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Uses of Sodium Chlorite and Sodium Bromate in Organic Synthesis
Authors: Krapcho A. Paul
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Transition Metal Catalyzed Highly Regio‐ and Stereoselective Organic Synthesis via Organozinc and Organoborane
Authors: Kimura Masanari
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Application of Alicyclic β‐Amino Acids in Peptide Chemistry
Authors: Fueloep Ferenc , Martinek Tamas A. , Toth Gabor K.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Dirhodium Tetraphosphine Catalysts
Authors: Stanley George G.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Recent Advances in Synthesis of α‐Hydroxy‐β‐amino Acids and Their Use in SAR Studies of Taxane Anticancer Agents
Authors: Chen Jin , Kuznetsova Larisa V. , Ungreanu Ioana M. , Ojima Iwao
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthetic Multivalent Ligands as Probes of Signal Transduction
Authors: Kiessling Laura L. , Gestwicki Jason E. , Strong Laura E.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Optimizing Dyes for Dye‐Sensitized Solar Cells
Authors: Robertson Neil
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Soils Contaminated by Heavy Metals: Geochemical Distribution and Restoration Techniques. Part 2
Authors: Galvez‐Cloutier R. , Lefrancois Pierre Jacques
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structure Features and Intermolecular Interaction Investigation in Long‐Chain Aliphatic Compounds by IR Spectroscopy Methods
Authors: Babkov L. M. , Vedyaeva E. S. , Trukhachev S. V.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Constituents of Caesalpinia crista from Indonesia.
Authors: Awale Suresh , Linn Thein Zaw , Tezuka Yasuhiro , Kalauni Surya Kant , Banskota Arjun Hari , Attamimi Faisal , Ueda Jun‐ya , Kadota Shigetoshi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Two New Sesquiterpene Polyesters from the Seeds of Euonymus nanoides Loes.
Authors: Wang Hong , Tian Xuan
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Keramische Schwämme – Anwendungspotenzial monolithischer Netzstrukturen als katalytische Packungen
Authors: Reitzmann A. , Patcas F. C. , Kraushaar‐Czarnetzki B.
Published: July 2006

Keramische Schwämme, in der Literatur oft auch als Schäume oder „foams”︁ bezeichnet, bieten durch ihre hochporöse und allseitig fluiddurchlässige Struktur viel versprechende Voraussetzungen für den Einsatz als katalytische Packungen in Festbettreaktoren. Die hier zusammengefassten Ergebnisse aus der Fachliteratur zeigen, dass potenzielle Anwendungen insbesondere für Reaktionen bestehen, bei denen hohe Fluiddurchsätze gefordert sind, starke Wärmetönungen auftreten und/oder der Stofftransport die Kinetik beeinträchtigt. Durch keramische Schwammpackungen lassen sich offenbar die Vorzüge von Formkörperschüttungen und Wabenkörpern vereinen. Anders als bei diesen Festbetten gibt es bei Schwammpackungen noch große Defizite in der quantitativen Beschreibung von Fluiddynamik, Wärme‐ und Stofftransport. So soll dieser Beitrag auch den Forschungsbedarf aufzeigen, der notwendig ist, um belastbare quantitative Kriterien für einen zweckmäßigen Einsatz katalytischer Schwammpackungen ableiten zu können.
Selektivhydrierung von Citral in organischem Lösungsmittel, in ionischer Flüssigkeit und in Substanz
Authors: Steffan M. , Lucas M. , Brandner A. , Claus P. , Wollny M. , Oldenburg N.
Published: July 2006

Untersucht wird das Katalysatorsystem Ag‐In/SiO2 auf seine Eignung zur Selektivhydrierung von Citral mit dem Ziel, die acyclischen, allylischen Terpenalkohole Geraniol/Nerol mit hoher Selektivität und Raum‐Zeit‐Ausbeute zu synthetisieren. Da Flüssigphasenhydrierungen häufig auch durch die Wahl des Lösungsmittels beeinflusst werden, ist außerdem von Interesse, in welcher Weise das Lösungsmittel insbesondere über seine Polarität und Wasserstofflöslichkeit die Aktivität und Selektivität von Katalysatoren bei der Hydrierung des α,β‐ungesättigten Aldehyds Citral beeinflusst.
Membranreaktoren für die katalytische Oxidation
Authors: Caro J.
Published: July 2006

Unter dem Begriff der „Prozessintensivierung”︁ erfolgen momentan intensive F&E‐Bemühungen, um auf den Kenntnissen der chemischen Reaktionstechnik und der Transportvorgänge aufbauend die Effizienz chemischer Prozesse zu steigern. Die Kombination einer Membran mit einer katalysierten Reaktion in einem Membranreaktor ist eines der Konzepte eines multifunktionalen Reaktors. Bislang haben chemische Membranreaktoren für Einsatztemperaturen > 100 °C keinen Eingang in die industrielle Praxis gefunden. Für diesen Temperaturbereich müssen anorganische Membranen entwickelt werden. Das entsprechende Entwicklungsniveau ist jedoch noch gering, es existiert noch keine großtechnische Gastrennung auf Basis anorganischer Membranen. Es zeichnet sich aber ab, dass membranunterstützte Partialoxidationen und selektive Hydrierungen an der Schwelle ihrer technischen Etablierung stehen. In diesem Beitrag werden Konzepte, Membranmaterialien und geeignete Reaktionen für die katalytische Partialoxidation in Membranreaktoren vorgestellt.
High‐Throughput‐Experimentation in der heterogenen Katalyse
Authors: Schüth F. , Demuth D.
Published: July 2006

High‐Throughput‐Experimentation wurde vor etwa zehn Jahren in die Katalyseforschung eingeführt und ist mittlerweile in vielen Labors zu einem der Standardwerkzeuge geworden. Während in spezifischen Projekten einzelne Komponenten, wie etwa Parallelreaktoren oder automatische Synthesestationen, mit großen Vorteilen eingesetzt werden können, entfaltet die Technologie ihre wirkliche Leistungsfähigkeit erst bei einer integrierten Herangehensweise, bei der komplette Arbeitsabläufe im Hochdurchsatzmodus implementiert werden. Dies reicht von der Software‐unterstützten Versuchsplanung über die Hochdurchsatzsynthese, Charakterisierung, parallelisierte Tests bis hin zur Computer‐gestützten Datenanalyse. Mit diesen Methoden sind seit ihrer Einführung bereits viel versprechende Katalysatorkandidaten entdeckt worden, teilweise auch bereits in die praktische Anwendung überführt worden. Die Komponenten und der gesamte Arbeitsablauf werden im Folgenden näher dargestellt.
Perceptions of performance: how European organizations experience EMAS registration
Authors: Pedersen Esben Rahbek
Published: July 2006

The literature on corporate social responsibility (CSR) is packed with attempts to uncover the business case of CSR. However, the findings are often based on either case stories or overall analyses of the business case for CSR, thereby overlooking the heterogeneity of the business landscape and the wide variety of CSR initiatives. This article intentionally tries to fall between the two chairs. By focusing on a single aspect of the blurry CSR concept, the article examines how European organizations perceive the motives, costs and benefits associated with EMAS (Environmental Management and Audit Scheme) registration. The article is based on a case analysis of Copenhagen Zoo and a web survey of 162 EMAS‐registered organizations. One of the main conclusions is that the respondents often perceive EMAS as a success even though they believe that the monetary costs from adopting the system outweigh the benefits. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
Methoxyphenyl‐Functionalized Diiron Azadithiolates as Models for the Active Site of Fe‐Only Hydrogenases: Synthesis, Structures, and Biomimetic H2 Evolution
Authors: Song Li‐Cheng , Ge Jian‐Hua , Zhang Xiao‐Guang , Liu Yang , Hu Qing‐Mei
Published: July 2006

A series of methoxyphenyl‐functionalized diiron azadithiolate (ADT) complexes, [{(μ‐SCH2)2N(C6H4OMe‐p)}Fe2(CO)5L] [L = CO (2); PPh3 (3); PPh2H (4)] and [{(μ‐SCH2)2N(C6H4OMe‐p)}Fe2(CO)4(CN)2][Et4N]2 (5) as the active site models of Fe‐only hydrogenases has been investigated. While model 2 was prepared in 67 % yield by a condensation reaction of N,N‐bis(chloromethyl)‐p‐methoxyaniline (1) with [(μ‐LiS)2Fe2(CO)6], models 3–5 were prepared in 49–75 % yields by a CO substitution reaction of 2 with PPh3, PPh2H, or Et4NCN, respectively. The X‐ray crystal structures of 2 and 3 revealed that the methoxyphenyl substituent is attached to the N atom by an axial bond and the nitrogen lone electron pair in an equatorial position. On the basis of cyclic voltammetric studies of 2 and 4, it was found that 2 is a catalyst for proton reduction, and an EECC mechanism is proposed for such electrocatalytic H2 production catalyzed by the ADT‐type models. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Characterization of Novel Oligoazulenes with Mixed Ethynyl and Butadiynyl Bridges
Authors: Elwahy Ahmed H. M. , Hafner Klaus
Published: July 2006

The new oligoazulenes 10–14 with mixed ethynyl and butadiynyl bridges were synthesized by oxidative Eglinton coupling from the readily accessible ethynylazulenes 3, 4, 7, 9 and 15 as well as by Pd/Cu‐catalyzed cross‐coupling reactions with the appropriate iodoazulenes 5, 6 and 8. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Foam Processing and Cellular Structure of Polycarbonate‐Based Nanocomposites
Authors: Ito Yasuhito , Yamashita Masatoshi , Okamoto Masami
Published: July 2006

Summary: Via a batch process in an autoclave, foam processing of intercalated PC/clay nanocomposites, having different amounts of clay, has been conducted using supercritical CO2 as a foaming agent. The cellular structures obtained from various foaming temperature‐CO2 pressure ranges were investigated by SEM. The incorporation with nanoclay‐induced heterogeneous nucleation occurs because of a lower activation energy barrier compared with homogeneous nucleation as revealed by the characterization of the interfacial tension between bubble and matrix. The controlled structure of the PCCN foams changed from microcellular (d ≅ 20 µm and Nc ≅ 1.0 × 109 cells · cm−3) to nanocellular (d ≅ 600 nm and Nc ≅ 3.0 × 1013 cells · cm−3). The mechanical properties of PCCN foams under compression test were discussed.

TEM micrograph for the structure of the cell wall foamed at 160 °C.

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TEM micrograph for the structure of the cell wall foamed at 160 °C.
Structure and Properties of Soy Protein Plastics Plasticized with Acetamide
Authors: Liu Dagang , Zhang Lina
Published: July 2006

Summary: Acetamide‐plasticized SPI sheets, denoted SAm, were prepared by compress molding at 140 °C and 20 MPa. The compatibility between acetamide and SPI has been investigated by DSC, WXRD, optical transmittance and SEM. Strong hydrogen bonding interaction between SPI and acetamide was evidenced by FT‐IR spectroscopy. When acetamide contents reached 30 phr the SAm exhibited best plasticity, leading to the highest elongation at break (178%) of the material. Moreover, the single glass transition temperatures of the SAm sheets decreased with an increase of acetamide content. Furthermore, the results from torque rheology revealed that the flexibility and processability were improved when the acetamide contents increased from 10 to 50 phr. Interestingly the acetamide‐plasticized SPI materials had better optical transmittance at 800 nm (75%) than that of glycerol‐plasticized SPI sheet, indicating a good compatibility of the SAm materials. At the same time, the results from TGA measurement and the water uptake indicated that SAm sheets possessed higher thermal stability and water‐resistance than those of glycerol‐plasticized SPI. This work provided a good plasticizer for SPI, and it is anticipated to use in biodegradable protein materials widely.

Water uptake of the SAm sheets at 35% RH.

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Water uptake of the SAm sheets at 35% RH.
Quantum Chemical Mapping of Initialization Processes in RAFT Polymerization
Authors: Coote Michelle L. , Izgorodina Ekaterina I. , Krenske Elizabeth H. , Busch Markus , Barner‐Kowollik Christopher
Published: July 2006

Summary: We present the first ab initio simulation of a reversible addition fragmentation chain transfer (RAFT) polymerization. Using ab initio molecular orbital theory, we calculate the equilibrium constants for the first eight addition–fragmentation steps in the cyanoisopropyl dithiobenzoate‐mediated polymerization of styrene. We then simulate the concentration profiles for the RAFT agent, and its unimeric and dimeric adducts, assuming standard experimental parameters for styrene homopolymerization and the addition of the styryl radical to the RAFT agent. The simulated data show excellent agreement with published experimental data, highlighting the accuracy of quantum chemistry. In contrast, the currently used chain‐length independent models fail to describe even the qualitative trends in the data, regardless of whether the fragmentation reaction is assumed to be fast or slow. The calculated chain‐length dependent equilibrium constants are large, in agreement with the earlier proposed slow fragmentation model.

Ab initio kinetic modelling of concentration profiles during the RAFT initialization period.

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Ab initio kinetic modelling of concentration profiles during the RAFT initialization period.
Synthesis and SFM Study of Comb‐Like Poly(4‐vinylpyridinium) Salts and Their Complexes with Surfactants
Authors: Gallyamov Marat O. , Starodubtsev Sergey G. , Khokhlov Alexei R.
Published: July 2006

Summary: Poly(4‐vinylpyridinium) bromides containing octyl and dodecyl pendant groups were synthesized. Bromide anions in these polymer salts were substituted with dodecylsulfate and bis(2‐ethylhexylsuccinate) anions using ion‐exchange reactions. Initially, P4VP and its derivatives loaded with hydrophobic groups were deposited on a mica surface from diluted solutions in chloroform for visualization. Images of single adsorbed macromolecules were obtained using scanning force microscopy. Original P4VP chains form partially compacted self‐intersecting coils. Loading the polymer chains with large hydrophobic groups and especially the increase in the number of alkyl tails (see Figure) per monomer unit of the polymer chain leads to the stretching of the coils, and the comb‐like macromolecules adopt more and more extended self‐avoiding 2D conformations when deposited on the substrate.

Polymer chains with large hydrophobic groups and increasing number of alkyl tails per monomer unit of the polymer chain.

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Polymer chains with large hydrophobic groups and increasing number of alkyl tails per monomer unit of the polymer chain.
Mutations in TITF1 are not relevant to sporadic and familial chorea of unknown cause
Authors: Bauer Peter , Kreuz Friedmar R. , Bürk Katrin , Saft Carsten , Andrich Jürgen , Heilemann Hubert , Riess Olaf , Schöls Ludger
Published: July 2006

Benign hereditary chorea (BHC; OMIM 118700) is an autosomal dominant movement disorder. Mutations in the thyroid transcription factor 1 (TITF1) gene have been linked with BHC. The phenotype for BHC is highly variable and may include atypical features such as dystonia, slow saccades, and even cognitive deficits. Although BHC is commonly transmitted in a dominant manner, assessment of TITF1 mutations in familial or sporadic patients with late‐onset nonprogressive or early‐onset progressive chorea is of practical relevance in order to evaluate diagnostic strategies in single patients. In this study, 18 patients with chorea of unknown cause including index patients of three families with autosomal dominantly inherited nonprogressive chorea have been screened for TITF1 mutations by means of denaturating high‐pressure liquid chromatography (dHPLC). No sequence variations were detected for the complete open reading frame, suggesting that TITF1 mutations are not a common cause of sporadic or familial chorea of unknown cause. Additionally, linkage analysis excluded TITF1 mutations in a large family with benign hereditary chorea. © 2006 Movement Disorder Society
Oscillations in the basal ganglia under normal conditions and in movement disorders
Authors: Gatev Plamen , Darbin Olivier , Wichmann Thomas
Published: July 2006

A substantial body of work within the last decade has demonstrated that there is a variety of oscillatory phenomena that occur in the basal ganglia and in associated regions of the thalamus and cortex. Most of the earlier studies focused on recordings in rodents and primates. More recently, significant advances have been made in this field of research through the analysis of basal ganglia field potentials recorded from implanted deep brain stimulation electrodes in the basal ganglia of human patients with Parkinson's disease and other disorders. It now appears that oscillatory activity may play a significant role in the pathogenesis of these diseases. The most significant finding is that in Parkinson's disease synchronized oscillatory activity in the 10‐ to 35‐Hz band (often termed “β‐band”) is prevalent in the basal ganglia–thalamocortical circuits, and that such activity can be reduced by dopaminergic treatments. The entrainment of large portions of these circuits may disrupt information processing in them and may lead to parkinsonian akinesia (and perhaps tremor). Although less firmly established than the role of oscillations in movement disorders, oscillatory activities at higher frequencies may also be a component of normal basal ganglia physiology. © 2006 Movement Disorder Society
Disturbance of rapid eye movement sleep in spinocerebellar ataxia type 2
Authors: Boesch Sylvia M. , Frauscher Birgit , Brandauer Elisabeth , Wenning Gregor K. , Högl Birgit , Poewe Werner
Published: July 2006

Five genetically confirmed spinocerebellar ataxia type 2 (SCA2) patients were admitted to our sleep laboratory for two all‐night video‐polysomnographies. A standard montage was used, including electroencephalography, vertical and horizontal electrooculography, electromyography of mental, submental, and tibialis anterior muscles, and respiratory monitoring. Four of five SCA2 patients had insufficient muscle atonia during rapid eye movement (REM) sleep. All patients exhibited myoclonic jerks during REM sleep, while elaborated behavior was not observed in the video. Abnormal motor control during sleep with periodic leg movements and REM sleep without atonia occurs frequently in SCA2. This finding may reflect a dysfunction of dopaminergic and/or brainstem and cerebellar outflow pathways. © 2006 Movement Disorder Society
Consideration of thermodynamic, transport, and mechanical properties in the design of polymer electrolyte membranes for higher temperature fuel cell operation
Authors: Choi Pyoungho , Jalani Nikhil H. , Thampan Tony M. , Datta Ravindra
Published: July 2006

A phenomenological theory is provided for water sorption and proton transport in polymer electrolyte membranes (PEMs) as well as in polymer‐inorganic nanocomposite membranes (NCPEMs) that not only serves to rationalize the sorption and conductivity behavior of conventional PEMs such as Nafion but also provides a framework for rational design of improved PEMs and NCPEMs. The thermodynamic model, which considers the effect of osmotic pressure on the activity of free water within the membrane pores, predicts the entire sorption isotherm and provides a plausible explanation for the so‐called Schroeder's paradox. The transport model incorporates the various mechanisms of proton transport, namely, surface hopping, Grotthuss diffusion, and en masse diffusion. As the design of alternate PEMs suitable for effective proton transport under hot and dry conditions is a key current technological goal, the rational design of NCPEMs for this purpose is considered here in detail on the basis of an extension of the transport model to account for the influence of the inclusion of functional additives in NCPEMs. The results also point to the reason that Nafion is an excellent PEM, because the hydrophobic nature of its backbone induces water away from surface into pore bulk where efficient proton diffusion occurs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2183–2200, 2006
Study of Surface Properties of Polyolefins Modified by Corona Discharge Plasma
Authors: Novák Igor , Pollák Vladimír , Chodák Ivan
Published: July 2006

Summary: Polyolefin surfaces, namely isotactic poly(propylene) (iPP) and low‐density polyethylene (LDPE), were modified by corona discharge plasma. The chemical changes on the modified surfaces were observed, deeply affecting the surface and the adhesive properties of the studied materials. The hydrophobic recovery in the case of iPP is considerably dependent on the polymer crystallinity. The presence of the processing agents in the LDPE has a significant influence on the surface hydrophobization dynamics.

Concentration of hydro peroxides in corona‐treated iPP versus the energy density: a) E‐iPP, and b) BO‐iPP.

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Concentration of hydro peroxides in corona‐treated iPP versus the energy density: a) E‐iPP, and b) BO‐iPP.
Improved robust stability criteria and design of robust stabilizing controller for uncertain linear time‐delay systems
Authors: Parlakçı M. N. Alpaslan
Published: July 2006

In this paper, an improved linear matrix inequality (LMI)‐based robust delay‐dependent stability test is introduced to ensure a larger upper bound for time‐varying delays affecting the state vector of an uncertain continuous‐time system with norm‐bounded‐type uncertainties. A quasi‐full‐size Lyapunov–Krasovskii functional is chosen and free‐weighting matrix approach is employed. Less restrictive sufficient conditions are derived for robust stability of time‐varying delay systems with norm‐bounded‐type uncertainties. Moreover, the investigation of the stabilization problem with memoryless state‐feedback control is presented such that the stabilizability criteria are obtained in terms of matrix inequalities, which can be solved via utilizing a cone complementarity minimization algorithm. Finally, the problem of output feedback stabilization for square systems is also taken into consideration. The output feedback stabilizability criteria are derived in the form of linear matrix inequalities, which are convex and can be easily solved using interior point algorithms. A plenty of numerical examples are presented indicating that the proposed stability and stabilization methods effectively improve the existing results. Copyright © 2006 John Wiley & Sons, Ltd.
Localized energy efficient routing in mobile ad hoc networks
Authors: Haque Israat Tanzeena , Assi Chadi
Published: July 2006

We consider the problem of localized energy aware routing in mobile ad hoc networks. In localized routing algorithms, each node forwards a message based on the position of itself, its neighbors and the destination. The objective of energy aware routing algorithms is to minimize the total power for routing a message from source to destination or to maximize the total number of routing tasks that a node can perform before its battery power depletes. In this paper we propose new localized energy aware routing algorithms called OLEAR. The algorithms have very high packet delivery rate with low packet forwarding and battery power consumption. In addition, they ensure good energy distribution among the nodes. Finally, packets reach the destination using smaller number of hops. All these properties make our algorithm suitable for routing in any energy constrained environment. We compare the performance of our algorithms with other existing energy and non‐energy aware localized algorithms. Simulation experiments show that our algorithms present comparable energy consumption and distribution to other energy aware algorithms and better packet delivery rate. Copyright © 2006 John Wiley & Sons, Ltd.
A novel cervical cancer suppressor 3 (CCS‐3) interacts with the BTB domain of PLZF and inhibits the cell growth by inducing apoptosis
Authors: Rho Seung Bae , Park Young Gyo , Park Kyoungsook , Lee Seung-Hoon , Lee Je-Ho
Published: July 2006

Promyelocytic leukemia zinc finger protein (PLZF) is a sequence‐specific, DNA binding, transcriptional repressor differentially expressed during embryogenesis and in adult tissues. PLZF is known to be a negative regulator of cell cycle progression. We used PLZF as bait in a yeast two‐hybrid screen with a cDNA library from the human ovary tissue. A novel cervical cancer suppressor 3 (CCS‐3) was identified as a PLZF interacting partner. Further characterization revealed the BTB domain as an interacting domain of PLZF. Interaction of CCS‐3 with PLZF in mammalian cells was also confirmed by co‐immunoprecipitation and in vitro binding assays. It was found that, although CCS‐3 shares similar homology with eEF1A, the study determined CCS‐3 to be an isoform. CCS‐3 was observed to be downregulated in human cervical cell lines as well as in cervical tumors when compared to those from normal tissues. Overexpression of CCS‐3 in human cervical cell lines inhibits cell growth by inducing apoptosis and suppressing human cyclin A2 promoter activity. These combined results suggest that the potential tumor suppressor activity of CCS‐3 may be mediated by its interaction with PLZF.
The non‐random distribution of intronless human genes across molecular function categories
Authors: Hill Aubrey E. , Sorscher Eric J.
Published: July 2006

It has been proposed that one function of introns is to coordinate expression across/within networks of related genes. This same hypothesis also predicts that intronless genes will not be uniformly distributed among the functional categories of human genes, but will be found most frequently in those categories that have less need to communicate changes in their expression. Statistical analysis demonstrates significant clustering of single exon genes among those with binding or signal transduction/receptor activities and fewer than expected among those with catalytic function.