bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Genetic Algorithm Based Approach to Coalescence Parameters: Estimation in Liquid‐Liquid Extraction Columns
Authors: Hasseine A. , Meniai A.‐H. , Korichi M. , Bencheikh Lehocine M. , Bart H.‐J. 
Published: November 2006

AbstractThe population balance model is a useful tool for the design and prediction of a range of processes that involve dispersed phases and particulates. The inverse problem method for the droplet population balance model is applied to estimate coalescences parameters for two‐phase liquid‐liquid systems. This is undertaken for two systems, namely toluene/water and n‐butyl acetate/water in a rotating disc contactor (RDC), using a droplet population balance model. In the literature, the estimation procedure applied to this problem is often based on the deterministic optimization approach. These methods generate instabilities near a local minimum, inevitably requiring information about the derivatives at each iteration. To overcome these limitations, a method providing an estimate for the coalescences parameters is proposed. It is based on a simple and adapted structure of the genetic algorithm, for this particular problem. The agreement between the experimental observations and the simulations is encouraging and, in particular, the models used have proven to be suitable for the prediction of hold‐up and Sauter diameter profiles for these systems. Finally, these results demonstrate that the optimization procedure proposed is very convenient for estimating the coalescences parameters for extraction column systems.
An Optimization of Capital and Operating Alternatives in a NGL Recovery Unit
Authors: Mehrpooya M. , Gharagheizi F. , Vatani A. 
Published: November 2006

AbstractA natural gas liquids (NGL) recovery unit currently in operation has been simulated and compared with a real unit. Optimized operating conditions have been determined, in which the objective function is based on cost analysis. Following this, different turboexpansion processes have been analyzed and the best flow sheet selected, based on capital analysis and operating limitations. Parameter optimization of the entire modified plant has been performed using an advanced genetic algorithm program, to determine optimal operating conditions. The best revamping alternative is a turboexpander‐exchanger process, in which case the profit is increased by 28 %.
Comparison of Selective Gas Phase‐ and Liquid Phase Hydrogenation of (Cyclo‐)Alkadienes towards Cycloalkenes on Pd/Alumina Egg‐Shell Catalysts
Authors: Wuchter N. , Schäfer P. , Schüler C. , Gaube J. , Miehe G. , Fuess H. 
Published: November 2006

AbstractThe hydrogenation of dienes such as 1,3‐butadiene, cyclooctadiene, and of acetylenic hydrocarbons on Pd catalysts shows high reaction rates and consequently, a strong influence of mass transfer on the selectivity of the intermediate alkene or cycloalkene product. 100 % selectivity towards (cyclo)‐alkene hydrogenation is achieved for the gas phase when the Thiele modulus is $ \varphi = L {\sqrt{ {k_1 c_{\rm H2}} \over {D_{\rm eff} c_{\rm diene}}}} \le {\sqrt{2}} $, where L is the thickness of the active layer and Deff is the effective diffusion coefficient of the diene. The interdependencies expressed by this formula were studied in detail using model catalysts with regular pores of uniform length and diameter and perpendicular to the surface. These catalysts were prepared by anodic oxidation of aluminium wires and immobilization of the active Pd. For the liquid phase procedure of selective hydrogenation, a reaction mass transfer model has been derived in order to compare the gas phase and liquid phase procedures, in particular with respect to the selectivity. The hydrogenation of 1,3‐cyclooctadiene and of 1,3‐butadiene were studied for both procedures employing the same catalyst. The rate of hydrogenation can be represented for both cases by the identical kinetic equation r1 = k1 cH2. This result is interpreted by assuming that the access of hydrogen to the surface through the dense layer of adsorbed diene is the rate determining step.
Synthesis, Fluorescence, and Two‐Photon Absorption of a Series of Elongated Rodlike and Banana‐Shaped Quadrupolar Fluorophores: A Comprehensive Study of Structure–Property Relationships
Authors: Mongin Olivier , Porrès Laurent , Charlot Marina , Katan Claudine , Blanchard‐Desce Mireille 
Published: November 2006

AbstractAn extensive series of push–push and pull–pull derivatives was prepared from the symmetrical functionalization of an ambivalent core with conjugated rods made from arylene–vinylene or arylene–ethynylene building blocks, bearing different acceptor or donor end‐groups. Their absorption and photoluminescence, as well as their two‐photon‐absorption (TPA) properties in the near infrared (NIR) region, were systematically investigated to derive structure–property relationships and to lay the guidelines for both spectral tuning and amplification of molecular TPA in the target region. Whatever the nature of the core or of the connectors, push–push systems were found to be more efficient than pull–pull systems, and planarization of the core (fluorene versus biphenyl) always leads to an increase in the TPA cross sections. In contrast, increasing the conjugation length as well as replacement of a phenylene moiety by a thienylene moiety in the conjugated rods did not necessarily lead to increased TPA responses. The present study also demonstrated that the topology of the conjugated rods can dramatically influence the TPA properties. This is of particular interest in terms of molecular engineering for specific applications, as both TPA properties and photoluminescence characteristics can be considerably affected. Thus, it becomes possible to optimize the transparency/TPA and fluorescence/TPA efficiency trade‐offs for optical limiting in the red‐NIR region (700–900 nm) and for two‐photon‐excited fluorescence (TPEF) microscopy applications, respectively.
Hydrogen‐Bond Interactions of Nicotine and Acetylcholine Salts: A Combined Crystallographic, Spectroscopic, Thermodynamic and Theoretical Study
Authors: Arnaud Virginie , Berthelot Michel , Evain Michel , Graton Jérôme , Le Questel Jean‐Yves 
Published: November 2006

AbstractThe hydrogen‐bond (HB) interactions of the monocharged active forms of nicotine and acetylcholine (ACh) have been compared theoretically by using density functional theory (DFT) calculations and experimentally on the basis of crystallographic observations and the measurement of equilibrium constants in solution. The 2,4,6‐trinitrophenolate (picrate) counterion was used to determine the experimental HB basicity of the cations despite its potential multisite HB acceptor properties. The preferred HB interaction site of the ammonium picrate salts was determined from a survey of crystallographic data found in the Cambridge Structural Database (CSD) and is supported by theoretical calculations. Two distinct classes of ammonium groups were characterised depending on the absence (quaternary ammonium) or presence (tertiary, secondary and primary ammoniums) of an N+H⋅⋅⋅O hydrogen bond linking the two ions. The crystal structure of nicotinium picrate was determined and compared with that of ACh. This analysis revealed the peculiar behaviour of the ammonium moiety of nicotinic acetylcholine receptor (nAChR) ligands towards the picrate anion. Dedicated methods have been developed to separate the individual contributions of the anion and cation accepting sites to the overall HB basicity of the ion pairs measured in solution. The HB basicities of the picrate anions associated with the two different ammonium classes were determined in dichloromethane solution by using several model ion pairs with non‐basic ammonium cations. The experimental and theoretical studies performed on the nicotine and ACh cations consistently show the significant HB ability of the acceptor site of nAChR agonists in their charged form. Both the greater HB basicity of the pyridinic nitrogen over the carbonyl oxygen and the greater HB acidity of the N+H unit relative to N+CH could contribute to the higher affinity for nAChRs of nicotine‐like ligands relative to ACh‐like ligands.
Synthesis and Photoinduced Electron‐Transfer Process of a Novel Triphenylamine‐Substituted Polyfluorene–C60 Triad
Authors: Chen Yu , El‐Khouly Mohamed E. , Zhuang Xiao‐Dong , He Nan , Araki Yasuyuki , Lin Ying , Ito Osamu 
Published: November 2006

AbstractThe photoinduced electron‐transfer process of a newly prepared, soluble, π‐conjugated poly[9,9‐bis(4‐diphenylaminophenyl)‐2,7‐fluorene] (PDPAF), covalently bridged, C60 triad (C60‐PDPAF‐C60) is described. The molecular orbital calculations revealed that the majority of the highest occupied molecular orbital (HOMO) is located on the polyfluorene entity, while the lowest unoccupied molecular orbitals (LUMO) are found to be entirely on the C60 entity. The excited‐state electron‐transfer processes were monitored by both steady‐state and time‐resolved emission as well as by transient absorption techniques in toluene and benzonitrile. By excitation of the polyfluorene moiety, fluorescence quenching of the singlet excited state of polyfluorene moiety was observed. The nanosecond transient spectra in near‐IR region revealed the charge‐separation process from the polyfluorene moieties to the C60 moiety through the excited singlet states of polyfluorene. The lifetimes of the charge separated states were evaluated to be 20–50 ns, depending on the solvent polarity.
Hydrothermal Synthesis of Molybdenum Oxide Based Materials: Strategy and Structural Chemistry
Authors: Michailovski Alexej , Patzke Greta R. 
Published: November 2006

AbstractThe preparative flexibility of hydrothermal syntheses needs to be systemised for exploring complex structure–synthesis relationships and morphology control options in materials chemistry. This is demonstrated for the targeted hydrothermal preparation of molybdenum oxide materials: firstly, in situ studies were employed for the efficient production of MoO3 nanofibres. Furthermore, ionic substances as structure‐directing tools brought forward a new class of fluorinated polyoxomolybdates.
A Cyclam Core Dendrimer Containing Dansyl and Oligoethylene Glycol Chains in the Branches: Protonation and Metal Coordination
Authors: Branchi Barbara , Ceroni Paola , Bergamini Giacomo , Balzani Vincenzo , Maestri Mauro , van Heyst Jeroen , Lee Sang‐Kyu , Luppertz Friedhelm , Vögtle Fritz 
Published: November 2006

AbstractWe have synthesized a dendrimer (1) consisting of a 1,4,8,11‐tetraazacyclotetradecane (cyclam) core, appended with four benzyl substituents that carry, in the 3‐ and 5‐positions, a dansyl amide derivative (of type 2), in which the amide hydrogen is replaced by a benzyl unit that carries an oligoethylene glycol chain in the 3‐ and 5‐positions. All together, the dendrimer contains 16 potentially luminescent moieties (eight dansyl‐ and eight dimethoxybenzene‐type units) and three distinct types of multivalent sites that, in principle, can be protonated or coordinated to metal ions (the cyclam nitrogen atoms, the amine moieties of the eight dansyl units, and the 16 oligoethylene glycol chains). We have studied the absorption and luminescence properties of 1, 2, and 3 in acetonitrile and the changes taking place upon titration with acid and a variety of divalent (Co2+, Ni2+, Cu2+, Zn2+), and trivalent (Nd3+, Eu3+, Gd3+) metal ions as triflate and/or nitrate salts. The results obtained show that: 1) double protonation of the cyclam ring takes place before protonation of the dansyl units; 2) the oligoethylene glycol chains do not interfere with protonation of the cyclam core and the dansyl units in the ground state, but affect the luminescence of the protonated dansyl units; 3) the first equivalent of metal ion is coordinated by the cyclam core; 4) the interaction of the resulting cyclam complex with the appended dansyl units depends on the nature of the metal ion; 5) coordination of metal ions by the dansyl units follows at high metal‐ion concentrations; 6) the effect of the metal ion depends on the nature of the counterion. This example demonstrates that dendrimers may exhibit complete functionality resulting from the integration of the specific properties of their component units.
Liquid‐Crystalline and Electron‐Deficient Coronene Oligocarboxylic Esters and Imides By Twofold Benzogenic Diels–Alder Reactions on Perylenes
Authors: Alibert‐Fouet Sonia , Seguy Isabelle , Bobo Jean‐François , Destruel Pierre , Bock Harald 
Published: November 2006

AbstractAlkyl esters, imides and imido‐esters of coronene‐tri‐, ‐tetra‐ and ‐octacarboxylic acids are accessible by a twofold oxidative benzogenic Diels–Alder reaction. Alkyl acrylates add to perylene, and maleic alkyl imides react twice with perylene as well as with perylene‐tetracarboxylic tetraesters. Coronenes substituted with a greatly variable number of electron‐withdrawing substituents are thus accessible, and di‐ and tetraimide derivatives are shown to be very pronounced electron‐acceptor materials. The tri‐ and tetraalkyl esters and imidoesters self‐assemble into columnar liquid‐crystalline phases.
Synthesis, Rietveld Analysis and Solid State Raman Spectroscopy of K4SrSi3O9.
Authors: Kahlenberg Volker , Kaindl Reinhard , Toebbens Daniel M. 
Published: November 2006

AbstractChemInform 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.
In3Ir3B, In3Rh3B and In5Ir9B4, the First Indium Platinum Metal Borides.
Authors: Kluenter Wilhelm , Jung Walter 
Published: November 2006

AbstractChemInform 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 Reinvestigation of Sillen X1‐Type Lead Tellurium Oxyhalides, Pb3TeO4X2 (X: Cl, Br, I).
Authors: Charkin Dmitri O. , Morozov Oleg S. , Ul'yanova Elizaveta A. , Berdonosov Peter S. , Dolgikh Valeri A. , Dickinson Calum , Zhou Wuzong , Lightfoot Philip 
Published: November 2006

AbstractChemInform 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.
Crystal Structure and Thermal Evolution of Inedite α‐Zr2O(PO4)2 and α‐Hf2O(PO4)2.
Authors: Wallez Gilles , Souron Jean‐Paul , Quarton Michel 
Published: November 2006

AbstractChemInform 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.
Tetrahedra and Vertex‐Sharing Double Tetrahedra in the Ammonium Iodomercurates(II) (NH4)7[HgI4]2 [Hg2I7](H2O) and (NH4)3[Hg2I7].
Authors: Nockemann Peter , Pantenburg Ingo , Meyer Gerd 
Published: November 2006

AbstractChemInform 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.
The Ammonium Bromomercurates(II) (NH4)Hg5Br11 and (NH4)4HgBr6.
Authors: Nockemann Peter , Pantenburg Ingo , Meyer Gerd 
Published: November 2006

AbstractChemInform 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.
Mg8Rh4B — A New Type of Boron Stabilized Ti2Ni Structure.
Authors: Alekseeva A. M. , Abakumov A. M. , Leithe‐Jasper A. , Schnelle W. , Prots Yu. , Chizhov P. S. , Van Tendeloo G. , Antipov E. V. , Grin Yu. 
Published: November 2006

AbstractChemInform 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.
Non‐Biaryl Atropisomers in Organocatalysis.
Authors: Brandes Sebastian , Niess Barbara , Bella Marco , Prieto Auxiliadora , Overgaard Jacob , Joergensen Karl Anker 
Published: November 2006

AbstractChemInform 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‐Catalyzed Cycloisomerization of Enyne Functionalities via a 1,3‐Alkylidene Migration.
Authors: Lin Ming‐Yuan , Das Arindam , Liu Rai‐Shung 
Published: November 2006

AbstractChemInform 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.
Domino “Staudinger/Semi‐Aza‐Wittig/Fragmentation” Reactions of γ‐Azido‐β‐hydroxyketones.
Authors: Freifeld Ilia , Shojaei Heydar , Dede Ruediger , Langer Peter 
Published: November 2006

AbstractChemInform 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.
Oxidation of Alcohols with 1‐Decyl‐4‐aza‐1‐azoniabicyclo[2.2.2]‐octane Chlorochromate under Conventional and Solvent‐Free Conditions.
Authors: Hajipour A. R. , Bagheri H. R. , Ruoho A. E. 
Published: November 2006

AbstractChemInform 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.
Rieke Zinc as a Reducing Agent for Common Organic Functional Groups.
Authors: Kroemer Jeremy , Kirkpatrick Chris , Maricle Brian , Gawrych Rick , Mosher Michael D. , Kaufman Don 
Published: November 2006

AbstractChemInform 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.
π‐Allylic Azidation in Water with an Amphiphilic Resin‐Supported Palladium—Phosphine Complex.
Authors: Uozumi Yasuhiro , Suzuka Toshimasa , Kawade Ray , Takenaka Hiroe 
Published: November 2006

AbstractChemInform 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 Efficient and Practical Procedure for Synthesis of α,α′‐Bis(substituted benzylidene)cycloalkanones Catalyzed by Solid Base SiO2‐OK.
Authors: Jin Tong‐Shou , Zhao Ying , Liu Li‐Bin , Li Tong‐Shuang 
Published: November 2006

AbstractChemInform 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.
Double Diastereoselective Acetate Aldol Reactions with Chiral N‐Acetyl Thiazolidinethione Reagents.
Authors: Zhang Yingchao , Sammakia Tarek 
Published: November 2006

AbstractChemInform 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 2,3‐Bis[allylsulfanyl(amino)methylidene]succinonitrile and Its Molecular and Crystal Structure.
Authors: Dyachenko V. D. , Chernega A. N. 
Published: November 2006

AbstractChemInform 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.
Bulky Alkylphosphines with Neopentyl Substituents as Ligands in the Amination of Aryl Bromides and Chlorides.
Authors: Hill Lensey L. , Moore Lucas R. , Huang Rongcai , Cracium Raluca , Vincent Andrew J. , Dixon David A. , Chou Joe , Woltermann Christopher J. , Shaughnessy Kevin H. 
Published: November 2006

AbstractChemInform 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 Secondary Amines by Titanium‐Mediated Transfer of Alkenyl Groups from Alcohols.
Authors: Ramanathan Balasubramanian , Odom Aaron L. 
Published: November 2006

AbstractChemInform 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 Modified H4‐BINOL Ligands and Their Applications in the Asymmetric Addition of Diethylzinc to Aromatic Aldehydes.
Authors: Lu Yong‐Na , Guo Qun‐Sheng , Jiang Fu‐Yong , Li Jin‐Shan 
Published: November 2006

AbstractChemInform 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.
Highly Selective 1,6‐Addition of Aryl Boronic Acids to α,β,γ,δ‐Unsaturated Carbonyl Compounds Catalyzed by an Iridium Complex.
Authors: Nishimura Takahiro , Yasuhara Yuichi , Hayashi Tamio 
Published: November 2006

AbstractChemInform 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 β‐Hydroxysulfides from Alkenes under Supramolecular Catalysis in the Presence of β‐Cyclodextrin in Water.
Authors: Surendra K. , Krishnaveni N. Srilakshmi , Sridhar R. , Rao K. Rama 
Published: November 2006

AbstractChemInform 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.
C—C Coupling Reactions of Aryl Bromides and Arylsiloxanes in Water Catalyzed by Palladium Complexes of Phosphanes Modified with Crown Ethers.
Authors: Gordillo Alvaro , de Jesus Ernesto , Lopez‐Mardomingo Carmen 
Published: November 2006

AbstractChemInform 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.
First Example of an Enantiospecific sp3—sp2 Stille Coupling of a Chiral Allylstannane with Aryl Halides.
Authors: Kalkofen Rainer , Hoppe Dieter 
Published: November 2006

AbstractChemInform 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.
Room Temperature Liquid Fullerenes: An Uncommon Morphology of C60 Derivatives.
Authors: Michinobu Tsuyoshi , Nakanishi Takashi , Hill Jonathan P. , Funahashi Masahiro , Ariga Katsuhiko 
Published: November 2006

AbstractChemInform 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.
Practical Cu‐Catalyzed Amination of Functionalized Heteroaryl Halides.
Authors: Yeh Vince S. C. , Wiedeman Paul E. 
Published: November 2006

AbstractChemInform 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.
Gold‐Catalyzed Highly Efficient Access to 3(2H)‐Furanones from 2‐Oxo‐3‐butynoates and Related Compounds.
Authors: Liu Yuanhong , Liu Meina , Guo Shenghai , Tu Huamin , Zhou Yebing , Gao Hongjun 
Published: November 2006

AbstractChemInform 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.
Preparation of Highly Substituted Pyrrolidines via an Organometallic Dipole.
Authors: Christie Steven D. R. , Davoile Ryan J. , Jones Raymond C. F. 
Published: November 2006

AbstractChemInform 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.