bluuebunny/crossref_metadata_2025_split huggingface dataset:
Science teachers’ perceptions of nanotechnology teaching and professional development: a survey study in Taiwan
Authors: Lin Shu-Fen , Chen Jun-Yi , Shih Kun-Yi , Wang Kuo-Hua , Chang Huey-Por 
Published: February 2015

AbstractInclusion of nanotechnology in the science curriculum has received great attention in many countries. Taiwan’s government has been funding the National Program on Nanotechnology (NPNT) for nearly 10 years. The purpose of this study was to examine Taiwanese secondary school science teachers’ understanding of nanotechnology teaching after implementing the NPNT, as well as the teachers’ perceptions of school support and their professional development intentions. The study adopted the questionnaire survey method. Using stratified cluster sampling, a total of 1600 questionnaires were distributed to 178 secondary schools. Finally, the responses of 663 junior high school teachers and 632 senior high school teachers who completed the instrument were analyzed. The instrument for the study is the Teachers’ Perceptions of Nanotechnology Teaching Scale (TPNTS). The TPNTS included 42 Likert-scale items. The results reveal that secondary school teachers’ intentions to pursue professional development are high, but their perceptions of school support are low. Teachers’ knowledge and understanding of nanotechnology teaching is significantly above average, but failed to reach the “very satisfied” level. In addition, the senior high school teachers’ perceptions of nanotechnology teaching and professional development are significantly higher than those of the junior high school teachers. Implications of the findings are discussed.
A comprehensive review on biodegradable polymers and their blends used in controlled-release fertilizer processes
Authors: Majeed Zahid , Ramli Nur Kamila , Mansor Nurlidia , Man Zakaria 
Published: February 2015

Abstract
Biodegradable polymer-coated controlled-release fertilizers (PC-CRFs) are essential means to reduce cost, improve marketability, conserve land fertility, achieve high crop yields and combat climate challenges. It is known that about 15–30% of any fertilizer packed in a PC-CRF does not get released due to the concentration gradient difference across the polymer coatings. To release the trapped fertilizer(s), it is desired that polymer-based coatings should biodegrade after the fertilizer is completely released into the soil. This review has aimed to provide a comprehensive account for various biodegradable polymers/blends derived either from natural or synthetic sources which are cited in the literature for PC-CRFs. In addition, this review covers the discussion on their classification criteria, trends in the processes of fertilizer coatings, methodological issues for their biodegradation assessment, coating attributes that affect the biodegradability and an outlook into their biodegradation kinetic models that involve enzymes and microbial processes. It also concludes that experimental as well as modeling data are insufficient to assess the biodegradation contribution of the overall nutrient release in PC-CRFs.
Business cycle (de)synchronization in the aftermath of the global financial crisis: implications for the Euro area
Authors: Bekiros Stelios , Nguyen Duc Khuong , Uddin Gazi Salah , Sjö Bo 
Published: February 2015

AbstractThe introduction of Euro currency was a game-changing event intended to induce convergence of Eurozone business cycles on the basis of greater monetary and fiscal integration. The benefit of participating into a common currency area exceeds the cost of losing autonomy in national monetary policy only in case of cycle co-movement. However, synchronization was put back mainly due to country-specific differences and asymmetries in terms of trade and fiscal policies that became profound at the outset of the global financial crisis. As opposed to previous studies that are mostly based on linear correlation or causality modeling, we utilize the cross-wavelet coherence measure to detect and identify the scale-dependent time-varying (de)synchronization effects amongst Eurozone and the broad Euro area business cycles before and after the financial crisis. Our results suggest that the enforcement of an active monetary policy by the ECB during crisis periods could provide an effective stabilization instrument for the entire Euro area. However, as dynamic patterns in the lead-lag relationships of the European economies are revealed, (de)synchronization varies across different frequency bands and time horizons.
A State of Inaction: Regulatory Preferences, Rent, and Income Inequality
Authors: Orbach Barak 
Published: February 2015

AbstractThis Article explores several meanings of a regulatory preference for government inaction. It explains the rise to dominance of this inaction preference in the United States and its distorting influence on the perception and understanding of regulation. Specifically, the Article demonstrates how basic terms in regulation, such as “government failure,” “regulatory capture,” and “deregulation,” acquired misleading connotations suggesting that government inaction is always superior to government action. The Article further explains how, through government inaction, the U.S. legal system accommodates rent extraction - the profitable exploitation of market imperfections and favorable laws. Several developments in recent decades have considerably improved the capacity of very small groups in society to collect rents, namely, use talent and positional advantages to gain increasing levels of earnings. The Article argues that the parallel rise of the inaction preference has contributed to this trend, primarily because the availability of rent extraction opportunities draws talent that utilizes them with growing effectiveness. The purpose of the Article is to clarify several aspects of the relationships between regulation and rent extraction or, more precisely, to emphasize that government inaction may entail undesirable income effects.
Dividend Policy with Controlling Shareholders
Authors: Sáez Maribel , Gutiérrez María 
Published: February 2015

AbstractThis Article investigates the determinants of dividend policy in firms with concentrated ownership structures. A review of the empirical literature shows that dividend payout ratios are lower in firms with controlling shareholders. We explain this finding as a consequence of the legal rules governing cash distributions, which leave the dividend decision in the hands of the firm insiders, and the lack of monitoring mechanisms for checking the power of controlling shareholders. The analysis of the empirical evidence on dividend policy points to the existence of an unresolved agency conflict between controlling shareholders and outside investors. We conclude that controlling shareholders are currently using the dividend policy to expropriate minority shareholders.
The Impact of the Financial Crisis on Nonfinancial Firms: The Case of Brazilian Corporations and the “Double Circularity” Problem in Transnational Securities Litigation
Authors: Gorga Érica 
Published: February 2015

AbstractThis Article discusses the impact of the international financial crisis on Brazilian capital markets. While the banking industry was not severely affected, leading nonfinancial corporations experienced severe financial turmoil. Two Brazilian corporations cross-listed in the United States - Sadia S.A. and Aracruz Celulose S.A. - suffered billion-dollar losses when the Brazilian real unexpectedly plummeted in relation to the dollar. Despite earlier disclosure that these companies had engaged only in pure hedging activity, these great losses were found to be the result of their highly speculative trading in currencyderivatives. Consequently, several private lawsuits were filed both in the United States and in Brazil.This Article takes a novel approach to the transnational securities litigation debate by examining the particular consequences of private litigation in a developed and in an emerging country. It compares the types of lawsuits filed and their final outcomes. Despite substantially similar alleged wrongdoing, the outcomes for securities holders in each jurisdiction contrast strikingly. Only U.S. investors of both companies were able to obtain substantial financial recoveries; Brazilian investors obtained none. This Article examines the reasons behind these discrepant results and the consequent economic distributional effects on global securities markets after the U.S. Supreme Court decision in Morrison.The Article argues that Morrison aggravates such (i) shareholder cross-border non pro rata compensation and (ii) transfers of company value from foreign to U.S. investors. It identifies a set of costs borne by foreign investors, and so far neglected by scholars, as a consequence of the current status of U.S. and international securities law regimes. These costs are the result not only of the typical “circularity problem” in securities litigation, but also of a “double circularity problem” as they fall on foreign shareholders who also suffered equivalent damages to those experienced by the U.S. class being compensated. The Article then discusses potential policy reforms for fixing transnational securities litigation.
Structure characterization of nanocrystalline porous materials by tomographic electron diffraction
Authors: Mugnaioli Enrico , Kolb Ute 
Published: February 2015

Abstract
Several porous phases have been characterized in the last years by tomographic electron diffraction. This paper provides an overview of the analyzed phases, pointing out the difficulties associated with different classes of materials or specific sample characteristics. The two methods for tomographic electron diffraction acquisition, automated diffraction tomography and rotation electron diffraction, are described in detail, as well as data reduction algorithms. Attainments and limits of different structure determination and refinement algorithms are discussed for inorganic, organic and hybrid organic-inorganic materials. Finally, it is shown how tomographic electron diffraction and X-ray powder diffraction data can be combined for a comprehensive characterization of porous materials.
Lattice Statics of a Hydrogen Centre in Magnesium
Authors: Bratschek B. , Rager B. , Volkert H.-J. 
Published: February 2015

In this work we consider the static perturbation of the hexagonal lattice of magnesium by one stored hydrogen atom.
Equations are given to evaluate the equilibrium positions of the ions in the disturbed crystal. The effect of the hydrogen atom is described by a so-called Kanzaki force, an additional force in the ideal lattice. The force between two ions of the ideal lattice is assumed to obey the harmonic approximation. The force constants are calculated form an effective ion-ion potential. The static Green tensor, which is the inverse of the tensor of force constants, is calculated and with its aid the equations of lattice statics are transformed. The transformed equations are solved under the assumption of a Kanzaki force acting only upon the nearest and next-nearest neighbors of the hydrogen atom at a tetrahedral interstitial site. Finally we calculate the volume change Δ V and compare the result with the experimental value.
Kristallstruktur und Schwingungsspektrum des Thallium(I)-Zinn(II)-ortho-Thiophosphates TlSnPS4
Authors: Becker Robert , Brockner Wolfgang , Eisenmann Brigitte 
Published: February 2015

TlSnPS4 crystallizes in the orthorhombic system, space group Pna21 (Nr. 33), Z = 4 with the lattice constants a = 1175.8 (5) pm, b = 890.1 (4) pm, c = 663.3 (4) pm. In the structure are sligthly distorted discrete PS3-
4 anions.
The far infrared, infrared and Raman spectrum is assigned on the basis of PS3-
4 -units with C3
v symmetry. According to the DTA data the melting point for TlSnPS4 is 575 ± 5 °C. The title compound is not moisture sensitive and semi-conducting.
Notizen: On the Relationship Between the Rates of the Radiative and Radiationless Deactivation of the Lowest Triplet State of Aromatic Compounds
Authors: Zander Maximilian 
Published: February 2015

Abstract
For groups of structurally related aromatic compounds with similar T1 - S0 energy gap linear correlations exist be­ tween the rate constants of the radiative and radiationless T1 → S0 transition. Significant exceptions may indicate further radiationless deactivation processes originating in T1 in addition to T1 → S0 intersystem crossing.
On the Concentration Fluctuations of a Binary Mixture of Hard Spheres
Authors: Gallego L. J. , Somoza J. A. , Blanco M. C. 
Published: February 2015

Abstract
We have computed the concentration fluctuations, Scc(0), in a binary mixture of hard spheres on the basis of the Percus-Yevick compressibility (PYC), Percus-Yevick virial (PYV) and Mansoori- Carnahan-Starling (MCS) equations of state. We have also used the Flory-Huggins (FH) model for an athermal solution as a first approximation to the hard sphere description. At fluid packing fraction values, the PYC and MCS theories give similar Scc (0) results, whereas the differences between these and those derived from the PYV equation are more significant. The FH model appears to give rather bad results, which is consistent with the studies of other authors on the entropy of mixing of a binary mixture of hard spheres. The impossibility of a fluid-fluid phase transition in this kind of system is clearly shown by the behaviour of Scc (0) in any of the theories studied.
X-ray Studies on Layer Stacking and Ordering in a Liquid Crystalline Disubstituted Biphenylcyclohexane
Authors: Klämke W. , Haase W. 
Published: February 2015

Abstract
X-ray measurements on disubstituted biphenylcyclohexanc BCH 52 show a crystalline smectic B phase with an ABCA layer stacking in bulk samples when cooled from the nematic to the smectic phase. No temperature dependence of this stacking can be seen. When cooling freely suspended thin films (below 20 μm) from the nematic to the smectic B phase, the obtained X-ray reflexes indicate an arrangement of the molecules in an orthorhombic F like stacking.
Phase Equilibria and Transport Properties in the Systems AgNO3/RCN/H2O. R = CH3, C2H5, C3H7, C4H,, C6H5, and C6H5CH2
Authors: Das Surjya P. , Wittekopf Burghard , Weil Konrad G. 
Published: February 2015

Abstract
Silver nitrate can form homogeneous liquid phases with some organic nitriles and water, even when there is no miscibility between the pure liquid components. We determined the shapes of the single phase regions in the ternary phase diagram for the following systems: silver nitrate /RCN /H2O with R =CH3, C3H7, C6H5, and C6H5CH2 at room temperature and for R =C6H5 also at 60 °C and O °C. Furthermore we studied kinematic viscosities, electrical conductivities, and densities of mixtures containing silver nitrate, RCN, and water with the mole ratios X /4 /1 (0.2≦ X ≦S 3.4). In these cases also R = C2H5 and C4H9 were studied. The organic nitriles show different dependences of viscosity and conductivity on the silver nitrate content from the aliphatic ones.
A New Model System for the Study of Complex Dynamical Enzyme Reactions. I. A Nonlinear Enzyme Reaction in a Chemical Gradient
Authors: Baier Gerold , Urban Peter , Wegmann Klaus 
Published: February 2015

Abstract
An experimental system for the study of biochemical reaction dynamics is introduced and de­ scribed. A one-enzyme reaction is extended by an artificial feedback loop in an electrochemical device. Cyclic voltammetry is used to show that the reaction rate depends nonlinearly on the amount of cosubstrate offered. For some sets of fixed parameter values a damped oscillatory approach of the steady state was observed. The usefulness of the systems theoretical concepts is discussed.
Dielectric Studies on HgCl2: 2 KCl Crystals
Authors: Sastry S. Sreehari , Rao V. Venkata , Satyanandam G. , Raj T. F. Sundar 
Published: February 2015

Abstract
The dielectric properties of HgCl2 : 2 K Cl crystals have been measured as a function of frequency (102-105 Hz) and temperature (304-415 K), along with the d.c. conductivity, in two mutually perpendicular (X and Y) directions. Along the X direction a simple Debye type relaxation mecha­nism is observed at 304 K. A large dielectric anisotropy has been noticed at all frequencies and temperatures. Phase transitions of ferroelectric and order-disorder type are observed along the X and Y direction, respectively.
Deuterium Quadrupole Coupling Constants of Deuterohalogenoacetylens
Authors: Heineking N. , Andolfatto M. , Kruse C. , Eberstein W. , Dreizler H. 
Published: February 2015

Abstract
Employing the high resolution of microwave Fourier transform spectroscopy, we investigated the lowest rotational transitions of fluoro-, bromo-, and iodoacetylene-d. Along with the rotational, centrifugal distortion, halogen nuclear quadrupole, and halogen spin-rotation coupling constants, we determined the deuterium quadrupole coupling constants of bromo-and iodoacetylene-d. For fluoroacetylene-d, we redetermined the deuterium nuclear quadrupole coupling constants with higher accuracy.
MINDO-Forces Calculations of 1-Substituted Cyclopropyl Cations and Anions
Authors: Khalil Salim M. 
Published: February 2015

Abstract
MINDO-Forces calculations are reported, after complete optimization of geometry, for 1-X-sub- stituted cyclopropyl cations and anions, where X is H, O-, OH, NH2, CH3, NO2, CN, F, CHO. All the substituents are stabilizing. It was found that the π-donating groups interact strongly with the cyclopropyl cations, whereas the π-withdrawing groups interact strongly with cyclopropyl anion depending on the electron demand.
Spinodal Decomposition in a Polystyren/ Cyclohexane Solution of Critical Composition
Authors: Schmitz G. , Klein H. , Woermann D. 
Published: February 2015

Abstract
Results of experiments are reported demonstrating spinoidal decomposition in a critical mixture of polystyrene and cyclohexane. If time and length are properly scaled using data obtained from static and dynamic light scattering exper­ iments, the time evolution of the “spinodal ring” is repre­sented to a good approximation by an empirical equation proposed by Snyder and Meakin which describes spinodal decomposition for various types of systems.
Laboratory Rotational Spectrum of PH (N = 2 ← 1) in the 1 THz Region
Authors: Klisch E. , Klein H. , Winnewisser G. , Herbst E. 
Published: February 2015

Abstract
The N = 2 ← 1 rotational transition of the PH radical in its ground electronic (X3 Σ- ) and vibrational states has been measured with the Cologne terahertz spectrometer in the frequency region between 920 and 1070 GHz. The PH radical was generated by immersing red phosphorus in a dc glow discharge of molecular hydrogen buffered with argon. Transition frequencies of the five J′ - J″ fine structure components together with the associated hyperfine structure patterns were precisely measured and analyzed to derive highly accurate molecular parameters, which are more extensive than those reported in the existing literature. Among the determined parameters are the rotational constant B0 = 252200.8099(63) MHz and the centrifugal distortion constant D0 = 13.2915(33) MHz, as well as two fine structure constants - the spin-rotation constant γ0 and the spin-spin interaction constant λ0 - together with their centrifugal distortion contributions Dγ0 and Dλ0. Furthermore, each of the magnetic hyperfine parameters bF, c, and the nuclear spin-rotation constants CI were obtained for both nuclei. The accuracy of previously obtained molecular constants has been improved by up to one order of magnitude. This new set of molecular parameters allows highly reliable frequency predictions of the rotational spectrum extending into the far infrared region; such transition frequencies may be of interest for interstellar spectroscopy.
MO-Theoretical Studies on a Model Complex for Deoxymyoglobin
Authors: Kollma Christian , Fischer Sighart F. , Böhm Michael C. 
Published: February 2015

Abstract
The origin of the displacement of the Fe atom in deoxymyoglobin with respect to the porphyrin plane in the high-spin state is examined by a qualitative molecular orbital (MO) analysis on the extended Hückel level. We find that attachment of a fifth ligand (imidazole in our model complex) to Fe(II)porphyrin favors the out-of-plane shift due to a strengthening of the bonding interaction between Fe and the nitrogen of the imidazole ligand. This results in a high-spin (5 = 2) ground state with Fe shifted out-of-plane for the five-coordinate complex instead of an intermediate spin ground state (5 = 1) with Fe lying in the plane for four-coordinate Fe(II)porphyrin. The relative energies of the different spin states as a function of the distance between Fe and the porphyrin plane are evaluated using an ROHF (restricted open shell Hartree-Fock) version of an INDO (intermediate neglect of differential overlap) method. We observe a level crossing between high-spin and intermediate spin states whereas the low-spin (5 = 0) state remains always higher in energy.
Direct Measurement of the Hydrogen-Hydrogen Correlations in Hydrogenated Amorphous Ni56 Dy44 by Neutron Diffraction
Authors: Lamparter P. , Nuding Ma. , Steeb S. , Bellissent R. 
Published: February 2015

Abstract
From an isotopic mixture of dysprosium with zero neutron scattering length and an isotopic mixture of nickel with zero neutron scattering length ribbons of the amorphous alloy Ni56 Dy44 were produced by melt-spinning and loaded with 59 at% deuterium. A neutron diffraction experiment yielded directly the deuterium-deuterium partial structure factor SDD and the partial pair correlation function GDD . The incorporation of the D-atoms into the amorphous matrix shows an ordering up to five coordination shells at least. The main peak of GDD is split up into a contribution at 2.36 Å with 5.4 nearest neighbours and a contribution at 2.76 Å with 4 neighbours. The D-atoms are located preferentially in Dy4 -tetrahedra, where the occupation of two neighbouring face-sharing tetrahedra is avoided.
Evidence of a Cationic Substitution Domain in Lithium-Manganese Spinels
Authors: Azzoni C. B. , Mozzati M. C. , Paleari A. , Massarotti V. , Bini M. , Capsoni D. 
Published: February 2015

Abstract
Magnetic susceptibility measurements and electron paramagnetic resonance spectra of samples prepared from the reactive system MnO/Li2CO3 with different starting Li cationic fraction x are analyzed, taking into account the structural and compositional information provided by x-ray diffraction. Parent phases, as Mn2O3 , Mn3O4 and Li2 MnO3 , arise together with the lithium-manganese spinel as a result of Li-deficiency or Li-excess with respect to the x = 0.33 composition pertinent to the stoichiometric LiMn2O4 spinel. The data show that the spinel phase can sustain a partial Li-Mn substitution in the cation sites, according to compositional models described, for x > 0.33, by Li1+y Mn3+
1-3y Mn4+
1+2y O4
(Li-rich spinel) and, for x< 0.33, by Li1-|y| Mn2+
|y| Mn3+
1+|y| Mn4+
1-|y| O4 (Li-poor spinel). Paramagnetic resonance data of the Li-poor spinel phase are analyzed to discuss the possible oxidation state of Mn in the tetrahedral site.
Thermische Zersetzung und Lösungskalorimetrie von Ammoniumneodymiodiden / Thermal Decomposition and Solution Calorimetry of Ammonium Neodymium Iodides
Authors: Hennig C. , Oppermann H. 
Published: February 2015

The thermodynamical data of ammonium neodymium iodides (NH4)3NdI6 and (NH4)2NdI5 were derived by the determination of their decomposition equilibria by total pressure measurements. Moreover, solution calorimetry was applied. The enthalpies of formation of these phases were calculated from their heats of solution and from the enthalpies of formation and the heats of solution of N dl3 and NH4I in 4n HI (aq.) at 298 K.
Data by total pressure measurement:
⊿H°B(NH4)3NdI6,f,298) = -306,7 ± 4,9 kcal/mol;
S°((NH4)3NdI6,f,298) = 152,8 ± 5,7 cal/K·mol;
⊿H°B(NH4)2NdI5,f,298) = -260,9 ± 4,2 kcal/mol;
S°((NH4)2NdI3,f,298) = 114,3 ± 4,7 cal/K·mol.
Data by solution calorimetry:
⊿H°B(NdI3,f,298) = -154,3 ± 2,0 kcal/mol;
⊿H°B((NH4)3NdI6,f,298) = -299,6 ± 3,2 kcal/mol;
⊿H°B((NH4)2NdI5,f,298) = -255,2 ± 2,8 kcal/mol.