bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wasserstoffbrückenassoziation und Exzeßfunktionen von Mischungen aliphatischer Amine mit Kohlenwasserstoffen oder Tetrachlorkohlenstoff
Authors: Wolff H. , Höpfner A. , Höppel H.‐E. 
Published: December 2015

AbstractAus den Aktivitätskoeffizienten von Mischungen aliphatischer Amine mit Kohlenwasserstoffen oder Tetrachlorkohlenstoff werden die freie Exzeßenthalpie GE, die Mischungsenthalpie HE und das Entropieglied T · SE für Temperaturen zwischen + 20 und ‐ 30 °C berechnet. Dabei zeigt sich bei den Amin‐Kohlenwasserstoff‐Systemen:Mit fallender Temperatur nimmt GE zu und nehmen HE sowie T. SE ab, bei gleichzeitiger Wanderung ihres Maximums zu kleineren Aminmolenbrüchen; mit wachsender Kettenlange des Amins nehmen die Exzeßfunktionen sämtlich ab, mit wachsender Kettenlange des Kohlenwasserstoffs aber sämtlich zu;die Funktionen zweier Mischungen, die denselben Kohlenwasserstoff und im einen Fall das normale, im anderen aber das am N‐ oder C‐Atom deuterierte Amin enthalten, unterscheiden sich nur innerhalb der Fehlergrenzen; (HE/x1)x1→0, die integrale Lösungswärme der Amine bis zu unendlicher Verdünnung, liegt bei etwa 2000 cal/mol.Die aufgezählten Beobachtungen lassen sich aus den bei der Verdünnung erfolgenden Änderungen der Wasserstoff‐ oder Deuteriumbrückenassoziation zwanglos deuten. Dabei belegt die Übereinstimmung, die die Funktionen der Systeme mit dem normalen und mit dem am N‐Atom deuterierten Amin innerhalb der Fehlergrenzen erkennen lassen, daß Wasserstoff‐ und Deuteriumbrückenassoziation sich höchstens geringfügig unterscheiden können. Der Wert von annähernd 2000 cal/mol für die integrale Lösungswärme bis zu unendlicher Verdünnung belegt, in Einklang mit früheren Berechnungen unmittelbar aus den Aktivitätskoeffizienten, daß die Assoziationsenergie der Aminmolekeln von ähnlicher Größe ist. Bei den nur für Dimethylamin berechneten Funktionen der Mischungen mit Tetrachlorkohlenstoff ist lediglich die Aussage möglich, daß GE nahezu 0 ist und HE sowie T · SEwesentlich kleiner als bei Dimethylamin‐n‐Hexan sind. Dies entspricht der Deutung, daß in den Tetrachlorkohlenstofflösungen nicht nur zwischen den Aminmolekeln, sondern auch zwischen den Amin‐ und den Tetrachlorkohlenstoffmolekeln eine spezifische Wechselwirkung besteht.
Spektroskopische Untersuchungen an Chalkogenometallaten: Elektronenabsorptionsspektren von VS43−, MoO222−, WO2S22 und ReO3S−. Schwingungsspektren, Kraftkonstanten und mittlere Schwingungsamplituden von VO43−, VS43−, MoS42−, WS42− und ReO3S−
Authors: Müller A. , Krebs B. , Rittner W. , Stockburger M. 
Published: December 2015

AbstractDie Elektronenabsorptionsspektren der Ionen VS43−, MoO222−, WO2S22 und ReO3S− in wäßriger Lösung werden mitgeteilt und diskutiert. Das Raman‐Spektrum des VO43− Ions in Lösung und das IR‐Spektrum von (NH4)3VS4 wurden gemessen. Mit Hilfe der Lasertechnik konnten die Raman‐Spektren der farbigen kristallinen Salze Cs2MoS4 (rot) und Cs2WS4 (gelb) aufgenommen werden. Kraftkonstanten eines allgemeinen und eines modifizierten Valenzkraftfeldes sowie des Urey‐Bradley‐Kraftmodells sind für VO43−, VS43−, MoS42− und WS42− angegeben. Nach der L‐Matrix‐Methode von Morino wurden mittlere Schwingungsamplituden bei 298 °K für diese lonen berechnet. Für ReO3S− werden Kraftkonstanten unter Annahme einer diagonalen F‐Matrix mitgeteilt. Die Valenzkraftkonstanten aller Ionen werden im Zusammenhang mit den Bindungsverhältnissen diskutiert.
Zur elektrischen Leitfähigkeit in nematischen Lösungen
Authors: Heppke G. , Schneider F. 
Published: December 2015

AbstractEs wird die äquivalentleitfähigkeit von Tetrapropylammoniumpikrat (TPAP) in N‐(p‐Methoxybenzyliden)‐p‐n‐butylanilin (MBBA) in Abhängigkeit von der Konzentration (7 ± 10−6 bis 5 ± 10−3 mol/l) und der Temperatur (16 bis 65°C) bestimmt. Die Meßwerte werden mit einem von Fuoss und Kraus angegebenen Verfahren auf unendliche Verdünnung extrapoliert.Die Abhängigkeit der Leitfähigkeit vom Winkel zwischen dem Magnetfeld, das zur Ausrichtung der nematischen Phase dient, und dem elektrischen Feld wird untersucht. Das Verhältnis der Extremwerte der Leitfähigkeit bleibt bei Konzentrationen unterhalb von 10−3 mol/l konstant. Die änderung dieses Anisotropieverhältnisses mit der Temperatur läßt sich, wie ein Vergleich mit bekannten Werten der Brechungsindizes zeigt, auf die Temperaturabhängigkeit des Ordnungsgrades zurückführen.
Einflüsse der Gasadsorption auf die Feldionisation an Eisen‐und Platinoberflächen
Authors: Schmidt W. A. , Frank O. , Block J. H. 
Published: December 2015

AbstractEs werden Einsatzspannungen der Feldionisation an Fe‐und Pt‐Emittern für die Edelgase Ar, Kr und Xe und für O2, CO, N2 und H2 massenspektrometrisch gemessen. Für die Edelgase erfolgt der Ionisationseinsatz an gereinigten Emitteroberflächen nach dem von der Theorie geforderten Zusammenhang zwischen Ionisierungsspannung des Gases und Austrittsarbeit des Metalles. Für die übrigen Gase werden erniedrigte oder erhöhte Einsatzspannungen gefunden, die durch adsorptionsbedingte Austrittsarbeitsänderungen nicht erklärt werden können.Es werden Einflüsse auf den Feldionisationsprozeß diskutiert, wobei chemische Wechselwirkungen und geänderte Elektronendichteverteilungen an der Emitteroberfläche in Betracht gezogen werden.
Substitution reactions of beryllium(II) ion in mixed solvents IV. Beryllium sulphate complexes in water‐hexamethylphosphoric triamide mixtures
Authors: Strehlow H. , Devia D. H. , Dagnall S. , Busse G. 
Published: December 2015

AbstractUsing conductivity and pressure jump relaxation measurements the complex formation of BeSO4 has been studied in mixtures of water and hexamethylphosphoric triamide (HMPT). The rate of substitution of a solvent molecule in the inner solvation sheath of the beryllium ion by a sulphate ion depends on the composition of the solvate species Be(HMPT)i(H2O)4‐i and on the type of solvent molecule being replaced by the sulphate ion. Above a mole fraction xHMPT ≥ 0.2 six relaxation processes have been observed. From the conductivity and the kinetic measurements the existence of a Be(SO4)22− complex was inferred in the mixed solvents. Measurements of the densities, dielectric constants and viscosities of the solvent mixtures are reported.
Interaction of carbon monoxide and hydrogen with metal films of Fe, Co, Ni, and FeCo‐alloy
Authors: Dittrich Th. , Buschmann H. W. , Vielstich W. 
Published: December 2015

AbstractThe interaction of carbon monoxide and hydrogen with metal films of Fe, Co, Ni, and FeCo‐alloy has been investigated by means of thermal desorption mass spectrometry. ‐ Since no exchange was observed between different CO‐isotopes adsorbed, desorption of CO can be treated as a first order reaction. At low coverages, the activation energies of desorption have been measured as 83,133,116, and 67 kJ/mol for Fe, Co, Ni, and FeCo‐alloy respectively. ‐ Hydrogen is adsorbed dissociatively. At low coverages the activation energies of desorption have been found to be 65, 110, 82, and 60 kJ/mol resp. ‐ The rate constants for desorption of both, CO and H2, strongly increase with increasing coverage. At saturation coverage, a dynamic equilibrium between the gas phase and the adsorbed molecules is established. ‐ CO inhibits the adsorption of H2 and displaces preadsorbed H2 in part. No reaction products have been observed following the coadsorption or the consecutive adsorption of CO and H2. ‐ The kinetics of the systems can be described by a system of coupled differential equations. The according solutions show that the pressure should exceed 0.1 Torr in order to observe CH‐reaction products, provided that the rate determining step of hydrocarbon formation is the hydrogenation of carbidic C‐atoms.
Two are Better Than One: The Link Between Management Systems and Business Performance
Authors: Ferrón Vílchez Vera , Darnall Nicole 
Published: December 2015

AbstractLittle is known about the complementary performance benefits associated with facilities’ combined use of both quality management systems (QMSs) and environmental management systems (EMSs), and how these performance benefits might differ from those associated with facilities’ use of only one of these management systems (or neither). We suggest that complementarities arise because each management system fosters the development of internal capabilities that facilitates the adoption and routine operationalization of the other, while maintaining differentiated goals that enhance strategic value. We examine these relationships using a sample of 2619 manufacturing facilities operating within six OECD countries, while controlling for self‐selection issues. Our findings support the idea of complementarity, in that facilities that adopt both QMS and EMS are more associated with positive business performance than facilities that adopt either a QMS or an EMS on its own, or no management system. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment
Numerical Study of Natural Convection in a Porous Cavity with Sinusoidal Thermal Boundary Condition
Authors: Wu Feng , Wang Gang , Zhou Wenjing 
Published: December 2015

AbstractThe steady natural convection in a rectangular cavity filled with a heat‐generating porous medium was numerically investigated using a thermal non‐equilibrium model for the heat transfer between the fluid and solid phases. All of the walls of the enclosure are adiabatic, except for the left wall, which is partially heated and cooled by a spatial sinusoidal temperature profile. The results show that the temperature fields near the left wall and the local Nusselt number of the left wall vary periodically because of the sinusoidal boundary condition. There exists an optimal fluctuant parameter of N (N = 3) to maximize the heat transfer rate of the fluid phase in the square enclosure. The periodicity parameter N has a significant influence on the value of the average Nusselt number of the fluid phase when the Darcy and Rayleigh numbers increase.
Foam Formation in Biogas Plants – A Survey on Causes and Control Strategies
Authors: Lindorfer Harald , Demmig Claudia 
Published: December 2015

AbstractExperiences of numerous full‐scale biogas plants on spontaneous foam formation were evaluated. Focus was laid on the feedstock mix, the causes of foaming, and control strategies. Mostly, the main digester was affected, but excessive foam formation in the post digester was found as well. The feedstock mix was stated as the main cause of foam formation followed by process troubles, abrupt degassing, temperature changes, and changes in viscosity. In the feedstock of plants affected by foaming, manure, cereals, sugar beets, and cosubstrates were used most often. Successful control strategies were gathered and categorized into seven groups: emergency measures, application of antifoam additives, avoidance of foam‐forming substrates, prevention of process upsets, changes of physicochemical conditions, optimization of mixing, and installation of technical equipment against foam formation.
Planarized Intramolecular Charge Transfer: A Concept for Fluorophores with both Large Stokes Shifts and High Fluorescence Quantum Yields
Authors: Haberhauer Gebhard , Gleiter Rolf , Burkhart Christoph 
Published: December 2015

AbstractFluorophores were successfully used in several areas of chemistry and biochemistry. For many purposes, however, it is necessary that the fluorescence compound features a high fluorescence quantum yield as well as a large Stokes shift. The latter is, for example, achieved by the use of a twisted intramolecular charge‐transfer (TICT) compound, which shows a twisted geometry in the excited state. However, the higher the twisting is, the lower becomes in general the fluorescence quantum yield as the resulting emission from the twisted state is forbidden. In order to escape this dilemma, we propose the model of planarized intramolecular charge‐transfer (PLICT) states. These compounds are completely twisted in the ground states and planar in the excited states. By means of quantum chemical calculations (time‐dependent (TD)‐B3LYP and CC2) and experimental studies, we could demonstrate that 1‐aminoindole and its derivatives form photoinduced PLICT states. They show both very large Stokes shifts (
=9000–13 500 cm−1, i.e., λ=100–150 nm) and high fluorescence quantum yields. These characteristics and their easy availability starting from the corresponding indoles, make them very attractive for the use as optical switches in various fields of chemistry as well as biological probes.
A Hexameric Cationic Copper(II) Metallacrown as a Pertechnetate and Perrhenate Scavenger
Authors: Rodríguez‐Hermida Sabina , Lago Ana Belén , Pino‐Cuevas Arantxa , Hagenbach Adelheid , Cañadillas‐Delgado Laura , Carballo Rosa , Abram Ulrich , Vázquez‐López Ezequiel M. 
Published: December 2015

AbstractMaterials based on the cationic copper(II) hexanuclear 18‐membered metallacrown [18‐MC
‐6]6+ (2phH=2‐piconyl hydrazide) and tetrafluoroborate, perchlorate, nitrate, sulfate, and perrhenate anions were prepared by an easy method in aqueous medium. Single‐crystal X‐ray characterization of six members of this new family of complexes showed that the anions are attached to the metallacrown by direct coordination to a copper cation or by hydrogen‐bonding interaction with the center of the hexamer. The stable cationic nature of the complexes and their ability to bind different anions allows them to adsorb and immobilize environmentally relevant anions such as MO4− (M=Tc, Re). The MO4− trapping capacities suggest that these materials would be useful in the treatment of oxoanionic contaminants in water.
N‐Alkyl Ammonium Resorcinarene Salts as High‐Affinity Tetravalent Chloride Receptors
Authors: Beyeh N. Kodiah , Pan Fangfang , Bhowmik Sandip , Mäkelä Toni , Ras Robin H. A. , Rissanen Kari 
Published: December 2015

AbstractN‐Alkyl ammonium resorcinarene salts (NARYs, Y=triflate, picrate, nitrate, trifluoroacetates and NARBr) as tetravalent receptors, are shown to have a strong affinity for chlorides. The high affinity for chlorides was confirmed from a multitude of exchange experiments in solution (NMR and UV/Vis), gas phase (mass spectrometry), and solid‐state (X‐ray crystallography). A new tetra‐iodide resorcinarene salt (NARI) was isolated and fully characterized from exchange experiments in the solid‐state. Competition experiments with a known monovalent bis‐urea receptor (5) with strong affinity for chloride, reveals these receptors to have a much higher affinity for the first two chlorides, a similar affinity as 5 for the third chloride, and lower affinity for the fourth chloride. The receptors affinity toward chloride follows the trend K1≫K2≫K3≈5>K4, with Ka=5011 m−1 for 5 in 9:1 CDCl3/[D6]DMSO.
Ruthenium‐Catalyzed Multicomponent Reactions: Access to α‐Silyl‐β‐Hydroxy Vinylsilanes, Stereodefined 1,3‐Dienes, and Cyclohexenes
Authors: Trost Barry M. , Koester Dennis C. , Sharif Ehesan U. 
Published: December 2015

AbstractThe synthesis of densly functionized α‐silyl‐β‐hydroxyl vinylsilanes via ruthenium‐catalyzed multicomponent reaction (MCR) is reported herein. Exceptionally high regio‐ and diastereoselectivity was achieved by employing an unprecedented hydrosilylation of bifunctional silyl‐propargyl boronates. The simple protocol, mild reaction conditions, and unique tolerability of this method make it a valuable tool for the synthesis of highly elaborated building blocks. The one‐pot synthesis of stereodefined olefins, the generation of a valuable cyclohexene building block through a four‐component MCR, and further functionalization in an abundance of diastereoselective reactions is disclosed herein.
How To Design a Successful p53–MDM2/X Interaction Inhibitor: A Thorough Overview Based on Crystal Structures
Authors: Estrada‐Ortiz Natalia , Neochoritis Constantinos G. , Dömling Alexander 
Published: December 2015

AbstractA recent therapeutic strategy in oncology is based on blocking the protein–protein interaction between the murine double minute (MDM) homologues MDM2/X and the tumor‐suppressor protein p53. Inhibiting the binding between wild‐type (WT) p53 and its negative regulators MDM2 and/or MDMX has become an important target in oncology to restore the antitumor activity of p53, the so‐called guardian of our genome. Interestingly, based on the multiple disclosed compound classes and structural analysis of small‐molecule–MDM2 adducts, the p53–MDM2 complex is perhaps the best studied and most targeted protein–protein interaction. Several classes of small molecules have been identified as potent, selective, and efficient inhibitors of the p53–MDM2/X interaction, and many co‐crystal structures with the protein are available. Herein we review the properties as well as preclinical and clinical studies of these small molecules and peptides, categorized by scaffold type. A particular emphasis is made on crystallographic structures and the observed binding modes of these compounds, including conserved water molecules present.
Little Thermodynamic Penalty for the Synthesis of Ultraporous Metal Organic Frameworks
Authors: Akimbekov Zamirbek , Navrotsky Alexandra 
Published: December 2015

AbstractMany metal–organic frameworks (MOFs) of ultrahigh porosity (with molar volumes more than ten times greater than those of the corresponding dense phases) have been synthesized. However, the number of possible structures far exceeds those that have been made. It is logical to ask if there are energetic barriers to the stability of ultraporous MOFs or whether there is little thermodynamic penalty to their formation. Herein, we show that although the molar volumes of MOF‐177 and UMCM‐1 reach ultrahigh values, their energetic metastability is in the same range (of 7–36 kJ mol−1) as that seen previously for other porous materials. These findings suggest that there is little thermodynamic penalty for the synthesis of structures with varying porosity, and hence, ultraporous frameworks are energetically accessible. Therefore, innovative synthesis methods have the possibility to overcome the drawbacks of conventional approaches and greatly extend the number, porosity, and properties of new framework materials.
Organic Carbonates: Efficient Extraction Solvents for the Synthesis of HMF in Aqueous Media with Cerium Phosphates as Catalysts
Authors: Dibenedetto Angela , Aresta Michele , di Bitonto Luigi , Pastore Carlo 
Published: December 2015

AbstractWe describe a process for the selective conversion of C6‐polyols into 5‐hydroxymethylfurfural (5‐HMF) in biphasic systems of organic carbonate/water (OC/W), with cerium(IV) phosphates as catalysts. Different reaction parameters such as the OC/W ratio, catalyst loading, reaction time, and temperature, were investigated for the dehydration of fructose. Under the best reaction conditions, a yield of 67.7 % with a selectivity of 93.2 % was achieved at 423 K after 6 h of reaction using [(Ce(PO4)1.5(H2O)(H3O)0.5(H2O)0.5)] as the catalyst. A maximum yield of 70 % with the same selectivity was achieved after 12 h. At the end of the reaction, the catalyst was removed by centrifugation, the organic phase was separated from water and evaporated in vacuo (with solvent recovery), and solid 5‐HMF was isolated (purity >99 %). The recovery and reuse of the catalyst and the relationship between the structure of the OC and the efficiency of the extraction are discussed. The OC/W system influences the lifetime of the catalysts positively compared to only water.
Simultaneous Recognition of Human Action and Its Location Estimation Based on Multiview Hough Voting
Authors: HARA KENSHO , HIRAYAMA TAKATSUGU , MASE KENJI 
Published: December 2015

SUMMARYRemote surveillance of large‐scale equipment such as power plants and building complexes is important to prevent serious attacks and troubles. Automatic human action recognition can reduce the burdens of the surveillance. Multiview video is useful for human action recognition, because it provides robustness to the changes of people's appearance by orientation and occlusion. One problem of conventional multiview action recognition is that it requires both detection and tracking before action recognition. Human pose and motion vary depending on the person's action, and such variances may cause detection and tracking error. To solve this problem, previous work has proposed simultaneous action recognition and location estimation for single‐view videos using Hough voting. In this paper, we extend the Hough voting approach to simultaneous multiview action recognition and location estimation. Our proposed method independently casts votes for the action labels and spatiotemporal reference positions of actions in each view and integrates them using homographical transformations in the multiview extension. We evaluated our method and confirmed that it achieved high accuracy in action recognition and location estimation. The contribution of this paper is that it enables multiview action recognition without prior human detection and tracking.
Development of Ca2+‐Driven Microvalve Powered by Contractile Fiber of Vorticella
Authors: NAGAI MOETO , TANIZAKI KOHEI , KAWASHIMA TAKAHIRO , SHIBATA TAKAYUKI 
Published: December 2015

SUMMARYBioactuators, biological motors in living systems, are promising for integration and functionalization of microsystems. We have developed a Ca2+‐driven microvalve powered by a contractile fiber, a stalk of Vorticella. Cells of Vorticella convallaria were trapped in designed microchambers. Stalks were self‐grown in the chambers and their reversible linear actuations were controlled by regulating the concentration of Ca2+. A cell body, connected to a stalk, opened and closed a microchannel by the contraction and extension of the stalk. The flow field in the chamber was characterized to further optimize the actuation performance.
Application of the AC Superposition Method to Degradation Diagnosis of 22/33‐kV Class XLPE Cables
Authors: KUMAZAWA TAKAO 
Published: December 2015

SUMMARYWater trees in the insulator of XLPE cable may considerably reduce the dielectric breakdown voltage, thus being an important lifetime‐governing factor. The ac superposition method we have investigated is a new technique for hot‐line diagnosis of 6.6‐kV XLPE cables, and the diagnostic apparatus using this technique is now widely used in the distribution line field. In order to study the application of the ac superposition method to degradation diagnosis of 22/33‐kV class XLPE cables, we measured deterioration signals of the cables with water trees by a modification of the above diagnostic apparatus. The deterioration signals, hereafter called “ac superposition current”, were generated by an amplitude modulation effect due to the nonlinear resistance of water trees. Moreover, we evaluated the relationship between the ac superposition current and the ac breakdown voltage. It is difficult to judge whether a correlation between then is present or not because of the uneven distribution of the measured data. However, the ac superposition current tends to increase linearly with a decrease in the residual thickness of the insulator. For example, the ac superposition current was about 40 nA when the residual thickness decreased to 3 mm. Thus, we consider that the ac superposition method is effective for degradation diagnosis of 22/33‐kV class XLPE cables.
Design Method for Improving Motor Efficiency of Switched Reluctance Motor
Authors: NAKAZAWA YOSHIHIRO , OHYAMA KAZUHIRO , NOUZUKA KAZUMA , FUJII HIROAKI , UEHARA HITOSHI , HYAKUTAKE YASUSHI 
Published: December 2015

SUMMARYThe motor efficiencies of switched reluctance motors (SRMs) are inferior to those of permanent magnet synchronous motors. This paper describes a design procedure for an SRM to obtain a higher motor efficiency. The first step in the design procedure makes clear the principle for improving the motor efficiency. The cross‐sectional and axial shapes of the rotor and stator cores are designed by magnetic field analysis with the two‐dimensional (2D) and 3D finite element method. A high‐efficiency SRM with 12 stator poles and eight rotor poles is designed. The designed SRM was produced experimentally, and was tested to verify its performance. The motor efficiency was improved in comparison to the standard SRM with six stator poles and four rotor poles.