bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronic Structure, Chemical Bonding, and Solid‐State NMR Spectroscopy of the Digallides of Ca, Sr, and Ba
Authors: Haarmann Frank , Koch Katrin , Grüner Daniel , Schnelle Walter , Pecher Oliver , Cardoso‐Gil Raul , Borrmann Horst , Rosner Helge , Grin Yuri 
Published: January 2009

AbstractDelving into digallides: The characteristics of the chemical bonding of the digallides of the alkaline‐earth metals (see figure) have been studied by application of experimental methods, such as single‐crystal X‐ray diffraction and solid‐state NMR spectroscopy, in combination with quantum mechanical calculations.magnified imageCombined application of 69,71Ga NMR spectroscopy and quantum mechanical calculations reveals the chemical bonding in the digallides of Ca, Sr, and Ba. An analysis of the electron localization function (ELF) shows honeycomb‐like 63 nets of the Ga atoms as the most prominent structural features in SrGa2 and BaGa2. For CaGa2 a description of a 3+1‐coordinated Ga atom is revealed by the ELF and by an analysis of interatomic distances. The NMR spectroscopic signal shift is mainly due to the Knight shift and is almost equal for the investigated digallides, whereas the anisotropy of the signal shift decreases with the radius of the alkaline‐earth metals. Calculated and observed values of the electric field gradient (EFG) are in good agreement for CaGa2 and BaGa2 but differ by about 21 % for SrGa2 indicating structural instability. Better agreement is achieved by considering a puckering of the Ga layers. For BaGa2 an instability of the structure is indicated by a peak in the density of states at the Fermi level, which is shifted to lower energies when taking puckering of the Ga layers into account. Both structural modifications are confirmed by crystallographic information. The Fermi velocity of the electrons is strongly anisotropic and is largest in the (001) plane of the crystal structure. This results in an alignment of the crystallites with the [001] axis perpendicular to the magnetic field as observed in 69,71Ga NMR spectroscopy and magnetic susceptibility experiments. The electron transport is predominantly mediated by the Ga–Ga px‐ and py‐like electrons in the (001) plane. The specific heat capacity of BaGa2 was determined and indicated the absence of phase transitions between 1.8 and 320 K.
Conformational Change of Spermidine upon Interaction with Adenosine Triphosphate in Aqueous Solution
Authors: Maruyoshi Keisuke , Nonaka Kaori , Sagane Takeshi , Demura Tetsuo , Yamaguchi Toshiyuki , Matsumori Nobuaki , Oishi Tohru , Murata Michio 
Published: January 2009

AbstractA complex rotation: The solution conformation of spermidine (SPD) was elucidated by using diastereospecifically deuterated and 13C‐labeled derivatives to diagnose the orientation of seven conformationally relevant bonds. NMR coupling constants were determined for a complex formed from spermidine and adenosine triphosphate (ATP; see figure).magnified imageEndogenous polyamines, represented by putrescine, spermidine, and spermine, are known to exert their physiological functions by interacting with polyanionic biomolecules such as DNA, RNA, adenosine triphosphate (ATP), and phospholipids. Very few examples of conformation analysis have been reported for these highly flexible polymethylene compounds, mainly due to the lack of appropriate methodologies. To understand the molecular basis of the weak interaction between polyamines and polyanions that underlies their physiological functions, we aimed to elucidate the solution conformation of spermidine by using diastereospecifically deuterated and 13C‐labeled derivatives (1–7), which were designed to diagnose the orientation of seven conformationally relevant bonds in spermidine. 1H–1H and 13C–1H NMR coupling constants (3JH,H and 3JC,H) were successfully determined for a spermidine–ATP complex. The relevant coupling constants markedly decreased upon complexation. The results reveal that spermidine, when interacting with ATP, undergoes changes that make the conformation more bent and forms the complex with the triphosphate part of ATP in an orientation‐sensitive manner.
Supramolecular Assembly of Self‐Labeled Amphicalixarenes
Authors: Becherer Miriam S. , Schade Boris , Böttcher Christoph , Hirsch Andreas 
Published: January 2009

AbstractShape‐persistent micelles consisting of exactly 12 molecules (see picture), which coexist with rodlike micelles, are formed by the self‐labeled amphicalixarene at pH 7. In contrast to other examples of structurally defined micelles, this new type of amphiphile serves as a fluorescence reporter and provides an extended cavity structure in the hydrophilic part, thereby facilitating the inclusion of guest molecules.magnified imageThe synthesis and precise supramolecular organization of new amphicalixarene 4 bearing four rodlike aligned fluorescent terephthalic benzamide moieties in the upper rim is reported. The aggregation of 4 was monitored by a combination of fluorescence, conductometry, and cryo‐TEM measurements at different pH values and revealed significant structural differences. Most interestingly, we found that exactly 12 molecules of 4 assemble to form a spherical and structurally persistent micelle at pH 7, which coexists with rodlike micelles. In contrast to other examples of structurally defined micelles reported previously, this new type of self‐labeled amphiphile serves as a fluorescence reporter with the terephthalic units additionally providing an extended cavity structure in the hydrophilic part, which facilitates the inclusion of guest molecules. In addition to the observed formation of well‐defined micelles, the other highly important finding from this study is the fact that guest molecules directly influence the micellar organization because they can interact with both the free amphiphiles below the critical micelle concentration (cmc) or the micellar aggregate itself. These two types of interactions are especially pronounced in the case of the cationic pyrene derivative 10, which binds electrostatically with the amphiphile 4. In addition, a very unique membrane structure exhibiting a regular hexagonal pattern of 5 nm pores is formed by 4 at pH 4.
Catalyzed Vinylogous Mukaiyama Aldol Reactions with Controlled Enantio‐ and Diastereoselectivities
Authors: Frings Marcus , Atodiresei Iuliana , Runsink Jan , Raabe Gerhard , Bolm Carsten 
Published: January 2009

AbstractIn control: A new catalytic vinylogous Mukaiyama aldol reaction provides products with high diastereo‐ and enantioselectivities (up to 99 % de and ee; see scheme). The relative and absolute stereochemistry of a representative product was rigorously assigned by NMR and CD spectroscopies (measured and calculated), X‐ray diffraction, and quantum‐chemical calculations.magnified imageNo Abstract
ChemInform Abstract: The Crystal Structure of SrLaFeRuO6: A New Double Perovskite Oxide.
Authors: Shaheen R. , Bashir J. , Khan M. Nasir , Rauf Raabya , Siddique M. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structures of the Ln4‐xIn5‐yS13 (Ln: La, Ce, Pr and Nd; x = 0.08—0.12, y = 0.21—0.24), La3In1.67S7, Gd3InS6 and La4Ag2In4S13 Compounds.
Authors: Gulay L. D. , Daszkiewicz M. , Huch M. R. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Transport Properties of Solid Solutions Sr1‐xKxPbO3‐yFy (0 ≤ x, y ≤ 0.20).
Authors: Drozd V. O. , Gabovich A. M. , Solopan S. O. , Nedil'ko S. A. , Pekala M. , Dzyaz'ko O. G. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Photocatalytic Activity of La3+/S/TiO2 Photocatalyst under Visible Light.
Authors: Xia Huili , Zhuang Huisheng , Xiao Dongchang , Zhang Tao 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Characterization of a New Four‐Layer Aurivillius Phase Bi2SrNa2Nb4O15 and Its Protonated Form.
Authors: Liang Zhenhua , Tang Kaibin , Zeng Suyuan , Wang Dong , Li Tanwei , Zheng Huagui 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ring Expansion of Lactones and Lactams via Propiolate 1‐Carbon Intercalation.
Authors: Grant Tina N. , Benson Chantel L. , West F. G. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1,4‐Cyclohexadiene with Pd/C as a Rapid, Safe Transfer Hydrogenation System with Microwave Heating.
Authors: Quinn John F. , Razzano Dana A. , Golden Kathryn C. , Gregg Brian T. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: gem‐Difluorination in Superacid: The Dramatic Role of Halonium Ions.
Authors: Zunino Fabien , Liu Fei , Berrier Christian , Martin‐Mingot Agnes , Thibaudeau Sebastien , Jouannetaud Marie‐Paule , Jacquesy Jean‐Claude , Bachmann Christian 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Divergent Titanium‐Mediated Allylations with Modulation by Nickel or Palladium.
Authors: Campana Araceli G. , Bazdi Btissam , Fuentes Noelia , Robles Rafael , Cuerva Juan M. , Oltra J. Enrique , Porcel Susana , Echavarren Antonio M. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1,1,1,3,3,3‐Hexafluoroisopropanol: A Recyclable Organocatalyst for N‐Boc Protection of Amines.
Authors: Heydari Akbar , Khaksar Samad , Tajbakhsh Mahmood 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: An Efficient and Solvent‐Free Synthesis of Mixed ortho Esters.
Authors: Cosgrove Kelly L. , McGeary Ross P. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Aryl Norbornanes and Analogues via Palladium‐Catalyzed Hydroarylation with Arenediazonium Tetrafluoroborates.
Authors: Bartoli Gabriele , Cacchi Sandro , Fabrizi Giancarlo , Goggiamani Antonella 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Vibrational Relaxation of OH and CH Fundamentals of Polar and Nonpolar Molecules in the Condensed Phase
Authors: Sibert Edwin L. III , Ramesh Sai G. , Gulmen Tolga S. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Concentrated Emulsions. Physicochemical Principles of the Preparation and Stability
Authors: Babak V. G. 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Determination of Mycotoxins in Human Foods
Authors: Shephard Gordon Seymour 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Studies on the Constituents of Cucurbitaceous Plants
Authors: Kasai Ryoji 
Published: January 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Modelling of light transmittance and reflectance in flat fluidized photoreactors
Authors: Brucato A. , Iatridis D. , Yue P. L. , Rizzuti L. 
Published: January 2009

AbstractIn recent years several photon induced chemical reactions involving the use of a solid catalyst have been studied. Flat fluidized beds have proved to be promising devices for carrying out these photocatalytic reactions. There is therefore a need for the modelling of light interactions within such kinds of photoreactors.In this paper, a phenomenological model is proposed for simulating the light transmission and reflection in flat fluidized gas‐solid photoreactors. A detailed description of the model is presented. The model predictions were compared with experimental data and a satisfactory agreement was found. Correlations were also suggested for the estimation of model parameters.
Transient cooling of petroleum by natural convection in cylindrical storage tanks: A simplified heat loss model
Authors: Cotter Mark A. , Charles Michael E. 
Published: January 2009

AbstractThe transient cooling by natural convection of a warm crude oil contained in a large vertical cylindrical storage tank located in a cold environment is investigated. The governing mass, momentum and energy equations utilizing a temperature‐dependent apparent viscosity were solved numerically, and from the results a correlation is developed between the Nusselt number at the sidewall and the instantaneous Rayleigh number driving the time‐dependent flow. A simplified heat loss model is developed to predict the mean tank temperature over time, utilizing this correlation to calculate a time‐dependent heat transfer coefficient for the sidewall. The results from the simplified model are compared with the mean tank temperatures results from a simulation of the full natural convection equations for the cooling of a crude oil in a 60 m diameter tank, and excellent agreement is obtained.
Quasi‐steady state natural convection in a tilted porous layer
Authors: Robillard L. , Vasseur P. 
Published: January 2009

AbstractQuasi‐steady state laminar natural convection in an inclined porous layer is studied analytically and numerically. On the basis of the Darcy‐Oberbeck‐Boussinesq equations, the problem is solved analytically in the limit of a thin porous layer heated on one side by a constant heat flux while the other boundaries are maintained adiabatic. For quasi‐steady state, the flow and temperature fields and overall heat transfer rates are obtained in terms of the controlling parameters and the onset of convection in a bottom‐heated horizontal system is predicted. It is also demonstrated for the case of a bottom‐heated layer that for sufficiently small inclinations, multiple unicellular quasi‐steady states exist, some of which are unstable. A numerical study of the same phenomenon, obtained by solving the complete system of governing equations, is conducted. Good agreement is found between the analytical predictions and the numerical simulation.
Modélisation d'un four de calcination du coke de pétrole: II. Simulation du procédé
Authors: Perron J. , Nguyen H. T. , Bui R. T. 
Published: January 2009

AbstractUn modèle mathématique à une dimension en régime permanent a été développé sur ordinateur pour simuler en détail le procédé de la calcination du coke de pétrole dans les fours rotatifs.Une simulation mathématique est effectuée pour reproduire les conditions d'opérations qui prévalaient lors d'une journée normale d'opération afin de valider le modèle ainsi que d' étudier en détail les principales variables du procédé. On trouve que les sources d'énergie par combustion dans le procédé proviennent à 59.5 % de l'hydrogène, 14.6 % du carbone du lit, 13.8 % des particules de poussière, 11.3 % du méthane et 0.8 % des goudrons.Par la suite, une comparaison est faite avec les modèles existants pour dégager les points communs aux différents fours à l'étude et proposer des règles générates s'appliquant aux autres fours non étudiés. Dans le cas des fours étudiés, il apparaît que la température maximale du coke est atteinte entre 45 % et 55 % de la longueur totale du four, tandis que le dégagement des matières volatiles s'effectue entre 5 % et 60 % de la longueur comptée à partir de l'alimentation en coke.
Le cyclone: Un réacteur chimique. Application à la réaction de décarbonatation de NaHCO3
Authors: Lédé J. , Li H. Z. , Villermaux J. 
Published: January 2009

AbstractLe présent article a pour objet l'étude expérimentale et théorique du comportement du réacteur cyclone en maquette chaude. La réaction modèle utilisée est la décarbonatation de NaHCO3. Moyennant l'utilisation de connaissances acquises sur le fonctionnement de ce type de réacteur en maquette froide et tiède, il est possible de déterminer des constantes cinétiques en très bon accord avec les valeurs de la littérature obtenues dans des conditions totalement diffé‐rentes. Les mesures sont effectuées dans un très large domaine de conditions expérimentales (granuloméres, temps de passage de particules, températures de paroi et débits de solides). Les résultats révelènt le double intérêt du réacteur cyclone : dispositif de mesure de constantes cinétiques et réacteur de production à forte capacité de traitement.
An apparatus for phase equilibrium studies of carbon dioxide+heavy hydrocarbon systems
Authors: Han Buxing , Peng Ding‐Yu , Fu Cheng‐Tze , Vilcsak George 
Published: January 2009

AbstractAn apparatus for measuring the solubility of gas in liquid and that of liquid or solid in gas has been constructed. The apparatus can be used at system temperatures ranging from 20 to 70°C and at system pressures up to 15 MPa. The solubilities were determined by means of gravimetric measurements. The solubilities measured in this study for the carbon dioxide+n‐decane and carbon dioxide + naphthalene systems agree very well with the literature values. The vapor‐liquid equilibria of the carbon dioxide+Peace River bitumen system at 45 and 55 °C were studied. The new data indicate that the supercritical‐fluid carbon dioxide can extract a fair amount of the light components from Peace River bitumen.
Behavioral, social, and educational outcomes after pediatric stem cell transplantation and related factors
Authors: Barrera Maru , Atenafu Eshetu , Pinto Jennifer 
Published: January 2009

AbstractBACKGROUND:The purpose of the current study was to investigate longitudinally children's behavioral and social competence outcomes up to 2 years after pediatric stem cell transplantation (SCT) and related factors.METHODS:Ninety‐nine mothers and 24 youths completed standardized questionnaires (Child Behavior Checklist [CBCL] and Youth Self‐Report [YSR]) pre‐SCT, and 12 and 24 months after SCT; 26 teachers completed Teacher Report Form (TRF) at 24 months. Information regarding clinical (eg, diagnosis, cranial radiation, graft vs host disease [GVHD]), child (eg, age, sex, physical health), and familial (eg, maternal age, education, distress) factors was also obtained.RESULTS:Linear mixed regression models with compound covariance structure followed by adjusted pairwise analyses yielded significant improvements from pre‐SCT to 1 and 2 years after SCT in total scores; in externalizing and internalizing scores from pre‐SCT to 2 years after SCT; and in total competence from pre‐SCT to 1 year after SCT. Child's physical health, maternal age, and depression were found to be significantly associated with the total, internalizing, and externalizing CBCL scores, whereas GVHD, mother's age, and time since diagnosis were associated with CBCL competence scores. Diagnosis, cranial radiation, GVHD, child's physical health, and maternal age and education were associated with YSR total behavioral and competence scores. Finally, total TRF scores were associated with time since diagnosis; TRF educational and adaptability scores were associated with maternal education, age, and distress.CONCLUSIONS:Clinical, personal, and familial factors must be considered to understand the psychosocial outcomes of these survivors up to 2 years after SCT. This study has important implications for psychosocial interventions for this population. Cancer 2009. © 2009 American Cancer Society.