bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamik der elektrochemischen Lithiumspeicherung
Authors: Maier Joachim 
Published: April 2013

AbstractDie Thermodynamik der elektrochemischen Lithiumspeicherung wird explizit unter dem Aspekt betrachtet, dass es die Punktdefekte sind, die Speicherung ermöglichen. Während Li‐Defekte beweglich sind, müssen die meisten der anderen Punktdefekte angesichts der im Vergleich zum Schmelzpunkt der Elektrodenmaterialien niedrigen Prozesstemperatur als eingefroren betrachtet werden. Die Betrachtungsebene der Defektchemie ist für das Verständnis der Lade‐/Entladekurven im Gleichgewicht essentiell. Auf dieser Grundlage können Einphasen‐ und Mehrphasenspeichermechanismen bezüglich theoretischer Speicherkapazität und Spannung diskutiert werden. Von außerordentlichem Interesse auf dem Gebiet der Lithiumbatterien sind metastabile Materialien, vor allem nanokristalliner und amorpher Natur. Die Thermodynamik in Bezug auf Speicherung und Spannung, auch an Grenzflächen, verdient dementsprechend eine spezielle Behandlung. Außerdem wird der Zusammenhang zwischen reversibler Zellspannung und Lithiumgehalt für den neuartigen “Job‐Sharing”‐Mechanismus abgeleitet. Für die klassischen Arten der Speicherung werden thermodynamische Unterschiede zwischen Kathoden und Anoden herausgearbeitet. Dies geschieht mit speziellem Fokus auf der Suche nach neuen Materialien. Da sich dieser Aufsatz auf den Gleichgewichtszustand konzentriert, werden Phänomene unter Stromleitung nur am Rande diskutiert.
Thermodynamics of Electrochemical Lithium Storage
Authors: Maier Joachim 
Published: April 2013

AbstractThe thermodynamics of electrochemical lithium storage are examined by taking into account that it is the point defects that enable storage. While the Li defects are mobile, most of the other point defects have to be considered as frozen owing to the performance temperature being low compared to the melting point of the electrode materials. The defect chemistry needs to be considered to fully understand equilibrium charge/discharge curves. On this basis, single phase and multiphase storage mechanisms can be discussed in terms of theoretical storage capacity and theoretical voltage. Of paramount interest in the field of Li batteries are metastable materials, in particular nanocrystalline and amorphous materials. The thermodynamics of storage and voltage, also at interfaces, thus deserve a special treatment. The relationship between reversible cell voltage and lithium content is derived for the novel job‐sharing mechanism. With respect to the classic storage modes, thermodynamic differences for cathodes and anodes are elaborated with a special attention being paid to the search for new materials. As this contribution concentrates on the equilibrium state, current‐related phenomena (irreversible thermodynamics) are only briefly touched upon.
Effect of ferrocene substituents and ferricinium additive on the properties of polyaniline derivatives and catalytic activities of palladium‐doped poly(m‐ferrocenylaniline)‐catalyzed Suzuki–Miyaura cross‐coupling reactions
Authors: Chaicharoenwimolkul Laksamee , Chairam Sanoe , Namkajorn Montree , Khamthip Achjana , Kamonsatikul Choavarit , Tewasekson Udomchai , Jindabot Sudarat , Pon‐On Weeraphat , Somsook Ekasith 
Published: April 2013

ABSTRACTPoly(aniline‐co‐m‐ferrocenylaniline) and ferricinium‐doped poly(aniline‐co‐m‐ferrocenylaniline) were synthesized by a conventional chemical oxidative polymerization, then characterized by spectroscopic techniques and quantitative analyzes. Increasing of the percentages of m‐ferrocenylaniline in the copolymers resulted to a blue shift of UV–Vis absorption spectra. Broader EPR spectra indicated the loss of conjugation and crystallinity of copolymers. 1H NMR spectra confirmed the presence of ferrocene moieties and ferricinium in the polymers. The CV measurements showed that the electron withdrawing power of ferrocene moieties could lead to the decreasing of electron delocalization on the polymer main chain. The VSM results showed that as‐prepared copolymers were soft magnetic materials with very low magnetization. Pd‐doped poly(m‐ferrocenylaniline) as catalysts were utilized in the Suzuki–Miyaura cross‐coupling reactions to improve the catalytic activities. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1489–1497, 2013
In Vivo Probing of the Temperature Responses of Intracellular Biomolecules in Yeast Cells by Label‐Free Raman Microspectroscopy
Authors: Chiu Yu‐Fang , Huang Chuan‐Keng , Shigeto Shinsuke 
Published: April 2013

AbstractEnvironmental temperature is an essential physical quantity that substantially influences cell physiology by changing the equilibria and kinetics of biochemical reactions occurring in cells. Although it has been extensively used as a readily controllable parameter in genetic and biochemical research, much remains to be explored about the temperature responses of intracellular biomolecules in vivo and at the molecular level. Here we report in vivo probing, achieved with label‐free Raman microspectroscopy, of the temperature responses of major intracellular components such as lipids and proteins in living fission yeast cells. The characteristic Raman band at 1602 cm−1, which has been attributed mainly to ergosterol, showed a significant decrease (≈47 %) in intensity at elevated temperatures above 35 °C. In contrast to this high temperature sensitivity of the ergosterol Raman band, the phospholipid and protein Raman bands did not vary much with increasing culture temperature in the 26–38 °C range. This finding agrees with a previous biochemical study that showed that the initial stages of ergosterol biosynthesis in yeast are hindered by temperature elevation. Moreover, our result demonstrates that Raman microspectroscopy holds promise for elucidation of temperature‐dependent cellular activities in living cells, with a high molecular specificity that the commonly used fluorescence microscopy cannot offer.
Revealing the Atomic Structure of Intermetallic GaPd2 Nanocatalysts by using Aberration‐Corrected Scanning Transmission Electron Microscopy
Authors: Leary Rowan , de la Peña Francisco , Barnard Jonathan S. , Luo Yuan , Armbrüster Marc , Meurig Thomas John , Midgley Paul A. 
Published: April 2013

AbstractAberration‐corrected scanning transmission electron microscopy was used to elucidate the crystalline nature, morphologies and other catalytically relevant properties (such as defect structures and surface stability) of nanoparticulate Ga–Pd selective hydrogenation catalysts. Atomically resolved and chemically sensitive annular dark‐field (ADF) imaging revealed, directly, the distinct crystalline structures corresponding to the intermetallic compound GaPd2. A disordered over‐layer decorating the surface of the nanoparticles was studied in a spatially resolved manner using ADF imaging and electron energy‐loss spectroscopy. The analysis corroborated a partial decomposition of the intermetallic surface and formation of oxidic islands following exposure of the nanoparticles to ambient conditions. The direct imaging of the nanoparticles, the size of which predominantly falls into the sub‐10 nm range, revealed their morphologies and significant crystalline defects, including five‐fold twinning. The manifestation of the intermetallic compound in the nano‐sized catalysts is intriguing from a crystallographic perspective and the observed deviations from the bulk crystal structure are of catalytic significance.
Activity, Recyclability, and Stability of Lipases Immobilized on Oil‐Filled Spherical Silica Nanoparticles with Different Silica Shell Structures
Authors: Kuwahara Yasutaka , Yamanishi Takato , Kamegawa Takashi , Mori Kohsuke , Yamashita Hiromi 
Published: April 2013

AbstractCandida antarctica lipase A was immobilized on spherical silica nanoparticles with oil‐filled core and oil‐induced mesoporous silica shell with different silica shell structures. The immobilization of enzymes was achieved by directly adding enzymes to the oil‐in‐water emulsion system under ambient synthesis conditions, and the silica shell structure was controlled by the addition of the cosolvent ethanol to the initial synthesis medium. Detailed structural analysis revealed the formation of oil‐filled spherical silica nanoparticles with 3.4–4.2 nm mesopores randomly arranged in the silica shell; the thickness and pore characteristics of these pores markedly changed with the addition of ethanol. The retention of the enzyme activity during biocatalysis was significantly affected by the structural properties of the silica shells, and it was found that a thick and dense silica shell is essential to afford an active, recyclable, and stable biocatalyst. Furthermore, the oil encapsulated within the core cavity was found to play an important role in achieving a high catalytic efficiency.
Interlocked Porphyrin Switches
Authors: Coumans Ruud G. E. , Elemans Johannes A. A. W. , Rowan Alan E. , Nolte Roeland J. M. 
Published: April 2013

AbstractWe describe the synthesis of a series of interlocked structures from porphyrin–glycoluril cage compounds and bis(olefin)‐terminated viologens by an olefin‐metathesis protocol. The length of the chain connecting the olefin substituents with the viologen has a marked effect on the products of the ring‐closure reaction. Long chains give [2]‐ and [3]catenane structures, whereas short chains give a mixture of [3]‐, [4]‐, and [5]catenanes. For comparison several [2]rotaxane compounds were prepared. The interlocked catenane and rotaxane structures display switching behavior, which can be controlled by the addition of acid and base. The kinetic and thermodynamic parameters of the switching processes have been determined by NMR spectroscopy.
Hydrolysis of Tetravalent Cerium for a Simple Route to Nanocrystalline Cerium Dioxide: An In Situ Spectroscopic Study of Nanocrystal Evolution
Authors: Ikeda‐Ohno Atsushi , Hennig Christoph , Weiss Stephan , Yaita Tsuyoshi , Bernhard Gert 
Published: April 2013

AbstractDespite the rapid developments in recent nanocrystal research and their expanding applications, the evolution mechanism of nanocrystals remains veiled for the most part due to the lack of appropriate analytical techniques. Here we demonstrate one promising multi‐spectroscopic approach for the in situ investigation of nanocrystal evolution. That is, the formation of nanocrystalline cerium dioxide (NC‐CeO2) has been probed by dynamic light scattering (DLS), X‐ray absorption spectroscopy (XAS) and high‐energy X‐ray scattering (HEXS). The obtained results indicate that the fine colloidal particles of NC‐CeO2are formed in an acidic aqueous solution simply through the hydrolysis of the initial precursor of small oligomer CeIVspecies. This information on how NC‐CeO2evolves is fundamental to simplifying and alleviating the synthetic strategy for NC‐CeO2production.
Molecular Switches and Multiple Logic Gates Based on 4‐(2‐Pyridylazo)resorcinol
Authors: Tao Zhanhui , Qin Yinan , Liu Yaqing , Xu Lei , Wang Erkang 
Published: April 2013

AbstractA simple‐structured 4‐(2‐pyridylazo)resorcinol (PAR) system presents interesting properties with dual fluorescent outputs. Modulated by solution pH two kinds of reversible switch behaviors, "ON‐OFF" and "OFF‐ON", were realized with the PAR system. Stimulated by different combination of external stimulus, such as metal ions, UV irradiation and solution pH, the PAR system could perform multiple logic functions including three inputs AND, two inputs INHIBIT and combinatorial "NOR/AND" in parallel. The operation of the designed system is very simple and detected with a high sensitive fluorescent signal.
Multichannel Chromogenic and Chiral Anions Recognition by Imidazolium Functionalized BINOL Derivatives
Authors: Lu Qiaosen , Hou Jiting , Wang Jian , Xu Bangyu , Zhang Ji , Yu Xiaoqi 
Published: April 2013

AbstractNew imidazolium/benzimidazolium‐containing receptors (R)‐1–(R)‐6 were developed as multifunctional receptors for both chromogenic and chiral anion recognition through multichannel. The ?uorescence spectra of (R)‐1 showed a distinct and intense peak at 454, 474 nm with AcO− and F−, respectively, indicating that (R)‐1 can be applied to the detection of fluoride and acetate ions by naked eye. Receptor (R)‐5, containing a lipophilic dodecyl appendage at imidazolium nitrogen, exhibited larger fluorescent responses than (R)‐1. The ratio of fluorescence enhancement for (R)‐5 with AcO− (I460/I369=16) and F− (I485/I369=11) was 32‐fold and 18‐fold over (R)‐1 with AcO− (I454/I369=0.5) and F− (I474/I369=0.6), respectively. Less electron‐deficient benzimidazolium receptor (R)‐2 only gave fluorescence enhance at 555 nm for F−. Only chelation enhanced quenching (CHEQ) effect was obtained in the case of mono‐imidazolium receptor (R)‐4. Furthermore, (R)‐1 and (R)‐5 displayed a remarkable binding ability for the t‐Boc alanine anion with interesting enantioselectivity [KL/KD=4.5 for (R)‐1 and 4.1 for (R)‐5)], whereas only negligible enantioselectivity ability (KL/KD=1.1) was obtained by using C1 symmetric receptor (R)‐4.
Synthesis, Structure and H+/K+‐ATPase Inhibitory Activity of Novel Triazolyl Substituted Tetrahydrobenzofuran Derivatives via One‐pot Three‐component Click Reaction
Authors: Fang Hubiao , Jin Lei , Huang Nianyu , Wang Junzhi , Zou Kun , Luo Zaigang 
Published: April 2013

AbstractEleven triazolyl substituted tetrahydrobenzofuran derivatives were synthesized in high yields as novel H+/K+‐ATPase inhibitor via one‐pot CuI‐catalyzed three‐component click reaction of azide, secondary amine and 3‐bromopropyne under mild conditions in water. Their structures were characterized by NMR, IR, ESI‐MS, elemental analysis and single‐crystal X‐ray diffraction analysis. Most of the target compounds exhibited better H+/K+‐ATPase inhibitory activity than commercial omeprazole with IC50 values less than 15 µmol·L−1. The initial structure‐activity analysis suggested that the triazole substituted by cycloalkyl, aromatic ring or O‐containing side‐chain seemed to be beneficial for enhancing the activity.
Efficient Synthesis of Unsymmetrical Heteroaryl Ethers by a Transition Metal‐Free CO Cross‐Coupling Reaction of Activated and Unactivated Heteroaryl Chlorides with Alcohols and Phenols
Authors: Liu Quan , Lu Zhongxiang , Ren Wenfei , Shen Kaibo , Wang Yu , Xu Qing 
Published: April 2013

AbstractBy optimizing the reaction conditions via a careful screening of the bases and solvents, we developed an efficient transition metal‐free method for CO cross‐coupling of activated and unactivated heteroaryl chlorides with primary and secondary alcohols and phenols, providing a simple, efficient, and practical method for synthesis of the useful unsymmetrical heteroaryl alkyl and heteroaryl aryl ethers.
Drug Target Identification Using Affinity Core‐Shell Magnetic Nanoparticles and Mass Spectrometry
Authors: Wei Yunhuan , Wang Tongdan , Liu Chao , Zhang Qianqian , Wang Lishun , Tang Gongli , Kang Jingwu 
Published: April 2013

AbstractAffinity core‐shell magnetic nanoparticles (MNPs) were prepared for identifying the target proteins of drugs in the cell lysate when used in combination with nano‐high‐performance liquid chromatography tandem mass spectrometry (HPLC‐MS/MS)‐based shotgun proteomic analysis. A number of new potential targets of cyclosporine A (CsA) could be identified, owing to the high efficacy of the affinity MNPs in drug target identification. To the best of our knowledge, this is the first time to reveal such an abundant target spectrum of CsA.
Complexation of Triptycene‐Derived Macrotricyclic Host with Bisparaquat Derivative and Self‐Folding Guest: A Switchable Process Controlled by K+ Ions
Authors: Han Ying , Guo Jiabin , Cao Jing , Chen Chuanfeng 
Published: April 2013

AbstractTriptycene‐derived cylindrical macrotricyclic host with two dibenzo‐30‐crown‐10 cavities could form stable 1:1 complexes with not only polyether linked bisparaquat derivative but also a self‐folding A‐D‐A guest in solution and/or solid state. Moreover, it was found that switchable processes between the host and both the bisparaquat derivative and the self‐folding guest could be further controlled by potassium ions.
Stimulation of the midbrain periaqueductal gray modulates preinspiratory neurons in the ventrolateral medulla in the rat in vivo
Authors: Subramanian Hari H. , Holstege Gert 
Published: April 2013

ABSTRACTThe midbrain periaqueductal gray (PAG) is involved in many basic survival behaviors that affect respiration. We hypothesized that the PAG promotes these behaviors by changing the firing of preinspiratory (pre‐I) neurons in the pre‐Bötzinger complex, a cell group thought to be important in generating respiratory rhythm. We tested this hypothesis by recording single unit activity of pre‐Bötzinger pre‐I neurons during stimulation in different parts of the PAG. Stimulation in the dorsal PAG increased the firing of pre‐I neurons, resulting in tachypnea. Stimulation in the medial part of the lateral PAG converted the pre‐I neurons into inspiratory phase‐spanning cells, resulting in inspiratory apneusis. Stimulation in the lateral part of the lateral PAG generated an early onset of the pre‐I neuronal discharge, which continued throughout the inspiratory phase, while at the same time attenuating diaphragm contraction. Stimulation in the ventral part of the lateral PAG induced tachypnea but inhibited pre‐I cell firing, whereas stimulation in the ventrolateral PAG inhibited not only pre‐I cells but also the diaphragm, leading to apnea. These findings show that PAG stimulation changes the activity of the pre‐Bötzinger pre‐I neurons. These changes are in line with the different behaviors generated by the PAG, such as the dorsal PAG generating avoidance behavior, the lateral PAG generating fight and flight, and the ventrolateral PAG generating freezing and immobility. J. Comp. Neurol. 521: 3083–3098, 2013. © 2013 Wiley Periodicals, Inc.
Trajectory‐Based Nonadiabatic Dynamics with Time‐Dependent Density Functional Theory
Authors: Curchod Basile F. E. , Rothlisberger Ursula , Tavernelli Ivano 
Published: April 2013

AbstractUnderstanding the fate of an electronically excited molecule constitutes an important task for theoretical chemistry, and practical implications range from the interpretation of atto‐ and femtosecond spectroscopy to the development of light‐driven molecular machines, the control of photochemical reactions, and the possibility of capturing sunlight energy. However, many challenging conceptual and technical problems are involved in the description of these phenomena such as 1) the failure of the well‐known Born–Oppenheimer approximation; 2) the need for accurate electronic properties such as potential energy surfaces, excited nuclear forces, or nonadiabatic coupling terms; and 3) the necessity of describing the dynamics of the photoexcited nuclear wavepacket. This review provides an overview of the current methods to address points 1) and 3) and shows how time‐dependent density functional theory (TDDFT) and its linear‐response extension can be used for point 2). First, the derivation of Ehrenfest dynamics and nonadiabatic Bohmian dynamics is discussed and linked to Tully’s trajectory surface hopping. Second, the coupling of these trajectory‐based nonadiabatic schemes with TDDFT is described in detail with special emphasis on the derivation of the required electronic structure properties.
Pulse‐Train Photoelectron Spectroscopy of Electronic and Nuclear Dynamics in Molecules
Authors: Arasaki Yasuki , Takatsuka Kazuo 
Published: April 2013

AbstractWe theoretically study the application of a femtosecond pulse train to simultaneously probe the electronic excitation dynamics and nuclear vibrational motion in the excited‐state LiH molecule by means of time‐resolved photoelectron spectroscopy. The step‐like population transfers caused by continual interaction with a sequence of pulses and refractory periods are shown to give rise to time evolution of the photoelectron kinetic energy distribution as the history of molecular electronic and vibrational states. Such a signal should lead to a novel and direct way to investigate electronic and nuclear simultaneous dynamics involving multiple excited states.
Evaluating the COSMO‐RS Method for Modeling Hydrogen Bonding in Solution
Authors: Tshepelevitsh Sofja , Oss Merit , Pung Astrid , Leito Ivo 
Published: April 2013

AbstractThe ability of the Conductor‐like Screening Model for Realistic Solvation (COSMO‐RS) computational method to model hydrogen bond (HB) formation in solution is examined by comparing computational data with experimental data from literature. This is the first study of this kind where mixed solvents are also involved. Hydrogen bond formation is examined between neutral molecules, between acids and their anions, and between various anion receptor molecules and different anions in a number of aprotic solvents. HB formation equilibrium constants, the corresponding Gibbs’ free energies and, when available from the literature, enthalpies were calculated. The supermolecule (SM) approach and the contact probability (CP) approach were used. Both in the case of the SM and CP approach, good to very good correlations between the experiment and computations are found for complexes formed from neutral species, enabling quantitative predictions. When the HB acceptor is an anion, the correlations are poor and in some cases even qualitative predictions fail.
Energy and spectral efficiency trade‐off for the downlink OFDM‐distributed antenna systems
Authors: He Chunlong , Sheng Bin , You Xiaohu 
Published: April 2013

SUMMARYThis paper investigates an energy efficient optimization scheme for the downlink multiuser OFDM‐distributed antenna systems. We adopt a multicriteria optimization method to offer a systematic study on the relationship between spectral efficiency (SE) and energy efficiency (EE). First, we transform the energy efficient optimization problem with high complexity into a simpler downlink multiuser OFDM problem. Then, using the weighted sum method in multicriteria optimization, an optimal energy efficient scheme is presented to allocate the available power to balance the trade‐off between SE and EE efficiently. Simulation results demonstrate that the energy efficient scheme is effective, and there existed a trade‐off between SE and EE in the downlink multiuser OFDM‐distributed antenna systems. Copyright © 2013 John Wiley & Sons, Ltd.
Paternal inheritance of growth in fish pursuing alternative reproductive tactics
Authors: Wirtz‐Ocaňa Sabine , Schütz Dolores , Pachler Gudrun , Taborsky Michael 
Published: April 2013

AbstractIn species with indeterminate growth, age‐related size variation of reproductive competitors within each sex is often high. This selects for divergence in reproductive tactics of same‐sex competitors, particularly in males. Where alternative tactics are fixed for life, the causality of tactic choice is often unclear. In theAfrican cichlidLamprologus callipterus, large nest males collect and present empty snail shells to females that use these shells for egg deposition and brood care. Small dwarf males attempt to fertilize eggs by entering shells in which females are spawning. The bourgeois nest males exceed parasitic dwarf males in size by nearly two orders of magnitude, which is likely to result from greatly diverging growth patterns. Here, we ask whether growth patterns are heritable in this species, or whether and to which extent they are determined by environmental factors. Standardized breeding experiments using unrelated offspring and maternal half‐sibs revealed highly divergent growth patterns of male young sired by nest or dwarf males, whereas the growth of female offspring of both male types did not differ. As expected, food had a significant modifying effect on growth, but neither the quantity of breeding substrate in the environment nor ambient temperature affected growth. None of the environmental factors tested influenced the choice of male life histories. We conclude that inL. callipterusgrowth rates of bourgeois and parasitic males are paternally inherited, and that male and female growth is phenotypically plastic to only a small degree.