bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Diskontinuität der Besetzungszahlen bei der micellaren Solubilisierung
Authors: Klein U. K. A. , Miller D. J. , Hauser M. 
Published: September 2012

AbstractMit den Methoden der kinetischen Fluoreszenzspektroskopie kann man die Aggregationszahl, Gestalt und Struktur der Mizellen eines amphipathischen Stoffs untersuchen und erhält außerdem grundlegende Aufschlüsse über die mizellare Solubilisierung. Wie man insbesondere an der intramizellaren Energiewanderung und Excimerenkinetik erkennt, wirken die Mizellen der gängigen Detergentien mit Aggregationszahlen Größenordnung 100 nur für kleinere Solutmoleküle (etwa bis zur Größe des Naphthalins) ähnlich wie eine fein verteilte Solventphase, wogegen für die Solubilisierung größerer Aromaten und die darauf beruhenden Vorgänge die Diskontinuität der Besetzung der Mizellen mit 0, 1 oder 2 Solutmolekülen ausschlaggebend wird. — Die Aggregationszahl bzw. Mizellengröße von Na‐Dodecylsulfat wurde über einen größeren Bereich von Temperaturen und Ionenstärken ermittelt. Im weit überwiegenden Teil des Meßbereichs stellt sich heraus, daß die Mizellen maximal 2 Pyrenmoleküle aufnehmen können. Lediglich wenn man durch große Ionenstärken und nahe bei Raumtemperatur die Aggregationszahl stark erhöht (etwa um Faktor 4), findet man einen relevanten Anteil von mit 3 Pyrenmolekülen besetzten Mizellen. — Bei Anthracen, Benzpyren und Perylen tritt kaum eine höhere Besetzungszahl als 1 auf.
Flotative Anreicherung und Gewinnung von Uran aus Armerzlaugen
Authors: Heckmann K. , Karmann H. G. , Spurny J. 
Published: September 2012

AbstractEs wird ein Mikroflotationsverfahren beschrieben, das die Abtrennung und Gewinnung von Uran aus homogenen salzsauren Oder schwefelsauren Lösungen von Metallsalzen gestattet.In diesen Lösungen liegt Uran entweder als Chlorouranylat‐ oder als Sulfatouranylat‐Komplex vor. Beide Komplexe bilden zusammen mit Alkylpyridinium‐Ionen schwerlösliche Niederschläge wohldefinierter Zusammensetzung. Begleitmetalle bilden unter denselben Bedingungen entweder keine anionischen Komplexe oder keine schwerlöslichen Niederschläge. Dies ermöglicht die selektive Abtrennung des Urans von seinen Begleitmetallen. Die Dosierung des kationaktiven Tensids läßt sich so einstellen, daß die uranhaltigen Niederschläge flotieren und sich schnell und quantitativ aus den Mutterlaugen ausschäumen lassen. Die für die Flotation maßgebenden Parameter werden optimiert. Aus den uranhaltigen Niederschlägen läßt sich das Uran als Uranat in sehr reiner Form gewinnen. Das kationaktive Tensid kann praktisch vollständig in den Prozeß zurückgeführt werden.
Untersuchung von Adsorbern zur Anreicherung von Uran aus Meerwasser
Authors: Witte E. G. , Astheimer L. , Schenk H.‐J. , Schwochau K. 
Published: September 2012

AbstractOrganische Ionenaustauscher wurden auf ihre Eignung als Adsorber für die Anreicherung von Uran aus Meerwasser geprüft. Ein komplexierendes Polymerharz, das sich durch schnelle Uranaufnahme und hohe Selektivität auszeichnet, ist imstande, Uran aus natürlichem Meerwasser auf das 260000‐fache anzureichern.
Simultane Reaktionen von HCl und SO2 an dotierten Aktivkohlen
Authors: Reinke M. , Richter E. , Knoblauch K. , Jüntgen H. 
Published: September 2012

AbstractHCl und SO2 werden an kohlenstoffhaltigen Adsorbentien simultan abgeschieden. Bei Verwendung metallimprägnierter Aktivkohlen wird die Abscheideleistung insbesondere bzgl. HCl gesteigert Die besten Ergebnisse wurden mit Cu‐dotierten Aktivkohlen erreicht. ‐ Bei Versuchen mit einem Festbettadsorber im Labormaßstab unter Verwendung eines synthetischen Rauchgases, das neben den oben genannten Gasen die Komponenten O2, CO2 und (H2O)g sowie N2 als Trägergas enthielt, konnte folgendes festgestellt werden:
‐der Einfluß von Temperatur und Schütthöhe wirkt sich beim SO2 stärker aus als beim HCl,
‐ HCl und SO2 beeinflussen sich in der Weise, daß die Sorptionskapazitäten wechselseitig verändert werden.
Anreicherung von Chlorisotopen durch selektive Photoaddition
Authors: Stake M. , Marinero E. E. , Schäfer F. P. 
Published: September 2012

AbstractGasförmiges Jodmonochlorid (ICI) wird mit einem kontinuierlichen Single‐Mode‐Farbstofflaser vollständig isotopenselektiv elektronisch angeregt (1Σg+ ‐ 3II1). Dazu dient ein on‐line gesteuertes Farbstofflasersystem, das die Laserwellenlänge auf definierte Vibrations‐Rotations‐Übergänge stabilisiert. Die angeregten Moleküle lagern sich an die Dreifachbindung des Acetylens an und bilden Jodchloräthylen. Durch diese selektive Photoaddition können beide stabile Chlorisotope auf mehr als 97% Reinheit in einem Schritt angereichert werden, ausgehend in beiden Fällen vom natürlichen Gemisch (3:1). Dies entspricht für 37Cl einem Anreicherungsfaktor von β = 100 [1,2]. Die Anreicherung kann sowohl statisch als auch in einem Flußsystem erfolgen. Die Abhängigkeit der Anreicherung von Druck, Puffergas und Laserwellenlänge wird beschrieben.
On the problems of the kinetic evaluation of DTA curves and non‐isothermal rate curves of one‐step reactions in solution
Authors: Koch E. , Stilkerieg B. , Carlsen L. 
Published: September 2012

AbstractThe kinetics of one‐step reactions in solution was studied non‐isothermally (linear temperature increase in the external system) by Differential Thermal Analysis (DTA) in an apparatus using a stirring technique. — Based on the assumption of a proportionality between heat flux and reaction rate, experimental DTA curves were evaluated by three methods, a) calculation of rate constants according to the formula proposed by Borchardt and Daniels [9], b) calculation of rate constants from non‐isothermal rate curves deduced from the heat balance equation, c) deriving activation data by optimum fitting of the theoretical model curves generated by numerical integration of the rate law, to the experimental curve. — In all cases studied, results obtained by the three methods are in good agreement. They are also confirmed by values reported in the literature, which are obtained by isothermal methods. However, it is not possible to extract rate constants from the decaying portion of the DTA curves, since the weight of the kinetic information is decreased with reaction progress, whereas the influence of heat conductivity is increased. The nature of the dependence of the usable curve time range on kinetics (reaction order and specific time), cell constant, heating rate, and initial concentration which was tested by re‐evaluation of the theoretically generated curves confirms our model and may serve as independent evidence for the applicability of all three methods even assuming extreme values for relevant parameters.
Infrared chemiluminescence studies of the reactions H + PCl3, H + VOCl3, and H + CrO2Cl2
Authors: Sung J. P. , Setser D. W. , Heydtmann H. 
Published: September 2012

AbstractWe report the study of the three title reactions in a flowing afterglow apparatus using the method of IR‐chemiluminescence. HCl emission was observed from excited vibrational states in each case and attributed to the reactions. H + PCl3 → HCl(v' ≤ 5) + PCl2. H + VOCl3 → HCl(v' ≤ 4) + VOCl2. H + CrO2Cl2 → HCl(v' ≤ 4) + CrO2Cl.H + PCl33 yields a bell shaped vibrational distribution (N1: N2: N3: N4: N5 = 0.11: 0.24: 0.38: 0.17: 0.10) indicating a direct mechanism. The HCl product distribution for the two other reactions can be described by vibrational temperatures of 3890 ± 250 K (H + VOCl3) and of 4400 ± 350 K (H + CrO2Cl2). It is concluded that the chlorine abstractions H + VOCl3 and H + CrO2Cl2 proceed via formation of long lived complexes.
The reaction O + HO2 → OH + O2 studied with a LMR‐ESR‐spectrometer
Authors: Hack W. , Preuss A. W. , Temps F. , Wagner H. Gg. 
Published: September 2012

AbstractThe reaction. C + HO2 → HO + O2 (1).Was studied in an isothermal discharge flow system. The main carrier gas was Helium in the pressure range between 1 and 10 mbar. The atoms H, O, F and the radicals OH and HO2 were monitored with a combined ESR‐LMR‐spectrometer. The rate constant K1 was determined in three different reaction systems. — The experiments yielded the result. K1 (298 K) = (2.0 ± 0.6) 1013 [cm3/mol s].
Laserangeregte chemische Reaktionen mit Bortrichlorid
Authors: Schramm B. , Diez A. 
Published: September 2012

AbstractWir berichten über die Anregung chemischer Reaktionen von BCl3 mit CH4 durch Dauerstrich‐ und durch gepulste Laser. Dabei gelang es uns, bei getrennter Anregung von 10BCl3 oder von 11BCl3 im natürlichen Isotopengemisch eine isotopenselektive Reaktion nachzuweisen.
Low pressure pyrolysis of 1,1‐dimethyl‐1‐silacyclobutane
Authors: Basu S. , Davidson I. M. T. , Laupert R. , Potzinger P. 
Published: September 2012

AbstractPyrolysis of 1,1‐dimethyl‐1‐silacyclobutane (DMSCB) has been studied by VLPP and by another low pressure technique. An intermediate, C3H8Si, has been directly detected in the VLPP experiments and evidence is presented that it is dimethylsilaethylene (DMSE). The heat of formation and π‐bond energy of DMSE have been calculated along with related thermochemical quantities.
Master equations for photochemistry with intense infrared light (III) the influence of molecular parameters in URIMIR
Authors: Quack Martin 
Published: September 2012

AbstractThe influence of molecular parameters on the rate of unimolecular reactions induced by monochromatic infrared radiation (URIMIR) is considered in the range of validity of a Pauli master equation. Solutions of the master equation are obtained for a model series of bond fission reactions. A two parameter activation equation for the time dependent rate coefficient is established. The dependence of the steady state rate coefficient, the activation time, and further relevant rate parameters upon the threshold energy for reaction, the excitation quantum, the number of vibrational modes, and the integrated oscillator strength of the fundamental transition is established and summarized in three simple rules. Quantitative calculations for the case B intensity fall‐off are presented. The possibility of an absolute estimate of the rate parameters is discussed with the example of the URIMIR of CF3I.
Change in electrochemical properties of TiO2 caused by anodic polarization under illumination in acetonitrile solutions
Authors: Yoneyama Hiroshi , Murai Taka‐Aki , Tamura Hideo 
Published: September 2012

AbstractThe photoresponse of TiO2(rutile) was changed by anodic polarization under illumination in acetonitrile solutions containing electrolytes of very high electrochemical stability. The degree of the change was high for rutile having a high donor concentration. Electrochemical properties in the dark were also changed by the same anodic polarization. The drift of lattice defects, which occurs during the anodic polarization, seems to be responsible for the observed change in electrochemical properties.
Statistisch‐mechanische Fluktuationstheorie der Kinetik schneller Mischprozesse in offenen Flüssigkeiten
Authors: Craubner H. 
Published: September 2012

AbstractEs wird eine statistisch‐mechanische Fluktuationstheorie schneller Mischprozesse in offenen binären Flüssigkeiten entwickelt. Ausgehend von den Hamiltonschen Bewegungsgleichungen und der Kontinuitätsgleichung wird die Bedeutung des Konzentrationsgradienten in diesem Zusammenhang untersucht. Es zeigt sich, daß der schnellstmögliche Ausgleich nach plötzlicher Konzentrationserhöhung dann erfolgt, wenn die Richtungen von Geschwindigkeitsfeldvektor und negativem Konzentrationsgradienten koinzidieren. Davon ausgehend wird die „optimale differentielle Mischzeit”︁ von Konzentrationsfluktuationen berechnet. Durch Optimierungsanalyse wird die maximale natürliche Geschwindigkeit des Verlaufs von Konzentrationsfluktuationen bestimmt. Ferner wird gezeigt, daß die Entropieproduktion, die Energiedissipation, die Fluktuationsentropie und die freie Fluktuationsenthalpie bei schnellen Mischprozessen in offenen Flüssigkeiten Extremwerte sind.
Predictive models for the accumulation of a fluorescent marker protein in tobacco leaves according to the promoter/5′UTR combination
Authors: Buyel J. F. , Kaever T. , Buyel J. J. , Fischer R. 
Published: September 2012

AbstractThe promoter and 5′‐untranslated region (5′UTR) play a key role in determining the efficiency of recombinant protein expression in plants. Comparative experiments are used to identify suitable elements but these are usually tested in transgenic plants or in transformed protoplasts/suspension cells, so their relevance in whole‐plant transient expression systems is unclear given the greater heterogeneity in expression levels among different leaves. Furthermore, little is known about the impact of promoter/5′UTR interactions on protein accumulation. We therefore established a predictive model using a design of experiments (DoE) approach to compare the strong double‐enhanced Cauliflower mosaic virus 35S promoter (CaMV 35SS) and the weaker Agrobacterium tumefaciens Ti‐plasmid nos promoter in whole tobacco plants transiently expressing the fluorescent marker protein DsRed. The promoters were combined with one of three 5′UTRs (one of which was tested with and without an additional protein targeting motif) and the accumulation of DsRed was measured following different post‐agroinfiltration incubation periods in all leaves and at different leaf positions. The model predictions were quantitative, allowing the rapid identification of promoter/5′UTR combinations stimulating the highest and quickest accumulation of the marker protein in all leaves. The model also suggested that increasing the incubation time from 5 to 8 days would reduce batch‐to‐batch variability in protein yields. We used the model to identify promoter/5′UTR pairs that resulted in the least spatiotemporal variation in expression levels. These ideal pairs are suitable for the simultaneous, balanced production of several proteins in whole plants by transient expression. Biotechnol. Bioeng. 2013; 110: 471–482. © 2012 Wiley Periodicals, Inc.
Characteristics of the binding of a bacterial expansin (BsEXLX1) to microcrystalline cellulose
Authors: Kim In Jung , Ko Hyeok‐Jin , Kim Tae‐Wan , Choi In‐Geol , Kim Kyoung Heon 
Published: September 2012

AbstractPlant expansin proteins induce plant cell wall extension and have the ability to extend and disrupt cellulose. In addition, these proteins show synergistic activity with cellulases during cellulose hydrolysis. BsEXLX1 originating from Bacillus subtilis is a structural homolog of a β‐expansin produced by Zea mays (ZmEXPB1). The Langmuir isotherm for binding of BsEXLX1 to microcrystalline cellulose (i.e., Avicel) revealed that the equilibrium binding constant of BsEXLX1 to Avicel was similar to those of other Type A surface‐binding carbohydrate‐binding modules (CBMs) to microcrystalline cellulose, and the maximum number of binding sites on Avicel for BsEXLX1 was also comparable to those on microcrystalline cellulose for other Type A CBMs. BsEXLX1 did not bind to cellooligosaccharides, which is consistent with the typical binding behavior of Type A CBMs. The preferential binding pattern of a plant expansin, ZmEXPB1, to xylan, compared to cellulose was not exhibited by BsEXLX1. In addition, the binding capacities of cellulose and xylan for BsEXLX1 were much lower than those for CtCBD3. Biotechnol. Bioeng. 2013; 110: 401–407. © 2012 Wiley Periodicals, Inc.
Analysis of imidacloprid and pyrimethanil in shallot (Allium ascalonicum) grown under greenhouse conditions using tandem mass spectrometry: establishment of pre‐harvest residue limits
Authors: Park Jong‐Hyouk , Park Joon‐Seong , Abd El‐Aty A. M. , Rahman Md. Musfiqur , Na Tae‐Woong , Shim Jae‐Han 
Published: September 2012

ABSTRACTIn this study, the original Quick, Easy, Cheap, Effective, Rugged and Safe method was used for the extraction of imidacloprid and pyrimethanil followed by a rapid clean‐up through dispersive solid‐phase extraction technique with primary secondary amine sorbent and magnesium sulfate in shallot. Residues were analyzed using LC‐tandem mass spectrometry in positive‐ion electrospray ionization mode. The limits of detection and quantification were estimated to be 0.006 and 0.02 mg/kg, respectively. The samples were fortified at two different concentration levels (0.2 and 1.0 mg/kg), and the recoveries ranged between 79.7 and 83.9% with relative standard deviation values < 6%. The method was successfully applied for the establishment of the pre‐harvest residue limits (PHRL). The rate of disappearance of imidacloprid and pyrimethanil on shallot was described with first‐order kinetics (imidacloprid, y2 = 0.9670; pyrimethanil, y2 = 0.9841), with half‐lives of 2.87 and 2.08 days, respectively. Based on the dissipation patterns of the pesticide residues, the PHRL was recommended at 7.86 mg/kg for 14 days (PHRL14) and 1.98 mg/kg for 7 days (PHRL7) before harvest for imidacloprid, and 21.64 mg/kg for 7 days (PHRL7) and 9.28 mg/kg for 4 days (PHRL4) before harvest for pyrimethanil in shallot. Copyright © 2012 John Wiley & Sons, Ltd.
Clinical efficacy and safety of biodegradable polymer‐based sirolimus‐eluting stents in patients with diabetes mellitus insight from the 4‐year results of the create study
Authors: Li Yi , Han Yaling , Zhang Lei , Jing Quanmin , Wang Xiaozeng , Yan Gaoliang , Ma Yingyan , Wang Geng , Wang Shouli , Chen Xuezhi , Yang Lixia , Zhu Guoying , Liu Huiliang , Jiang Tieming 
Published: September 2012

BackgroundDiabetes mellitus is an independent predictor of adverse clinical events after drug‐eluting stent implantation.ObjectivesThe objective of this study is to evaluate the long‐term clinical efficacy and safety of biodegradable polymer‐based sirolimus‐eluting stents in diabetic versus non‐diabetic patients.MethodsA total of 2077 “all comers,” including 440 (21.2%) diabetic patients and 1637 (78.8%) non‐diabetic patients, were prospectively enrolled in the CREATE study at 59 centers in four countries. The recommended antiplatelet regimen was clopidogrel and aspirin for 6 months followed by chronic aspirin therapy. The primary outcome was the rate of major adverse cardiac events (MACE), defined as a composite of cardiac death, non‐fatal myocardial infarction (MI), and target lesion revascularization (TLR).ResultsDiabetic patients had higher risks of all‐cause death (8.2% vs. 3.4%, P < 0.001) and cardiac death (4.1% vs. 1.4%, P < 0.001) compared with non‐diabetic patients at 4 years. The rates of non‐fatal MI (0.2% vs. 0.9%, P = 0.218), TLR (2.0% vs. 2.8%, P = 0.357), MACE (5.9% vs. 4.4%, P = 0.227), and overall stent thrombosis (1.6% vs. 1.6%, P = 0.932) were not significantly different between diabetic and non‐diabetic patients. A landmark analysis showed that prolonged clopidogrel therapy (>6 months) was not beneficial in reducing the cumulative hazards of MACE either in diabetic or non‐diabetic patients (log rank P = 0.810).ConclusionsBiodegradable polymer‐based sirolimus‐eluting stents for the treatment of diabetic patients had a similar clinical event rate at 4 years compared with non‐diabetic patients, except for a higher mortality rate. © 2012 Wiley Periodicals, Inc.
Simultaneous Removal of NO and SO2 from Flue Gas by UV/H2O2/CaO
Authors: Liu Y. X. , Zhang J. , Wang Z. , Du M. 
Published: September 2012

AbstractThe effects of several influencing factors (CaO and H2O2 concentration, gas flow, solution temperature, NO, SO2, O2 and CO2 concentration) on the simultaneous removal of NO and SO2 from flue gas by using a UV/H2O2/CaO process were studied. In addition, the anions in the liquid phase were measured by ion chromatography and the material balances for NO and SO2 were calculated. It was found that, under all experimental conditions, this process achieved a SO2 removal efficiency of 100 %. With the increase in CaO concentration, NO removal efficiency first increased and then remained almost unchanged. With the increase in H2O2 concentration, NO removal efficiency increased but the changes gradually became smaller. NO removal efficiency greatly decreased with increasing gas flow, NO concentration and CO2 concentration. Slightly increasing the solution temperature and SO2 concentration reduced NO removal efficiency. Increasing O2 concentration can promote the removal of NO. The anions in the liquid phase were mainly SO42– and NO3–. Most of the low valence nitrogen elements in NO and the low valence sulfur elements in SO2 transformed into the high valence nitrogen element in NO3– and the high sulfur element in SO42–.
From Containers to Catalysts: Supramolecular Catalysis within Cucurbiturils
Authors: Pemberton Barry C. , Raghunathan Ramya , Volla Sabine , Sivaguru Jayaraman 
Published: September 2012

AbstractCucurbiturils are a family of molecular container compounds with superior molecular recognition properties. The use of cucurbiturils for supramolecular catalysis is highlighted in this concept. Both photochemical reactions as well as thermal transformations are reviewed with an eye towards tailoring substrates for supramolecular catalysis mediated by cucurbiturils.
Modeling and Optimization of Hybrid Dynamic Systems
Authors: Mynttinen Ines , Li Pu 
Published: September 2012

AbstractDie dynamische Optimierung kontinuierlicher Prozesse gehört heute in Forschung und Anwendung zum Stand der Technik. Viele Prozesse zeigen jedoch ein schaltendes Verhalten. Die dort auftretenden Schaltvorgänge führen beim Betrieb zu abrupten Änderungen der Dynamik. Diese Prozesse werden deshalb als Hybridsysteme bezeichnet. Aufgrund der schaltenden Dynamik ist die Optimierung dynamischer Hybridsysteme eine äußerst anspruchsvolle Aufgabe. Dieser Beitrag führt in die Problematik der Modellierung von Hybridsystemen ein und beschreibt derzeit verfügbare Methoden zur Optimierung dieser Systeme. Regularisierungsansätze bilden eine Hauptforschungsrichtung auf dem Gebiet der Optimierung dynamischer Hybridsysteme. Die Fallstudien zeigen die Anwendung zweier wichtiger Regularisierungsmethoden anhand einer Labor‐Tankanlage und eines industriellen Verdampfers.
Raw Materials for the Industrial Location of Bavaria – a Resource Strategy
Authors: Kroop Stefanie , Franke Matthias , Stenzel Fabian , Mocker Mario , Faulstich Martin 
Published: September 2012

AbstractDer Industriestandort Bayern ist mit seinem hohen Anteil an Hightech‐Unternehmen in besonderem Maße von wirtschaftsstrategischen Rohstoffen abhängig. Welche Rohstoffe für die bayerische Wirtschaft von großer Bedeutung sind und welche Abfallströme zur Substitution dieser Rohstoffe herangezogen werden können, soll im vorliegenden Beitrag dargestellt werden.
Calcium‐ and Voltage‐Gated Potassium (BK) Channel Activators in the 5β‐Cholanic Acid‐3α‐ol Analogue Series with Modifications in the Lateral Chain
Authors: Bukiya Anna N. , Patil Shivaputra A. , Li Wei , Miller Duane D. , Dopico Alex M. 
Published: September 2012

AbstractLarge conductance, calcium‐ and voltage‐gated potassium (BK) channels regulate various physiological processes and represent an attractive target for drug discovery. Numerous BK channel activators are available. However, these agents usually interact with the ubiquitously distributed channel‐forming subunit and thus cannot selectively target a particular tissue. We performed a structure–activity relationship study of lithocholic acid (LCA), a cholane that activates BK channels via the accessory BK β1 subunit. The latter protein is highly abundant in smooth muscle but scarce in most other tissues. Modifications to the LCA lateral chain length and functional group yielded two novel smooth muscle BK channel activators in which the substituent at C24 has a small volume and a net negative charge. Our data provide detailed structural information that will be useful to advance a pharmacophore in search of β1 subunit‐selective BK channel activators. These compounds are expected to evoke smooth muscle relaxation, which would be beneficial in the pharmacotherapy of prevalent human disorders associated with increased smooth muscle contraction, such as systemic hypertension, cerebral or coronary vasospasm, bronchial asthma, bladder hyperactivity, and erectile dysfunction.