The 100 most prolific economists using the <Emphasis Type=Italic>p</Emphasis>-index

The h-index has captured the imagination of scientometricians and bibliometricians to such an extent that one can now divide the history of the subject virtually into a pre-Hirsch and a post-Hirsch period. Beyond its academic value, it is now used as a tool for research assessment of individuals, research faculties and institutions and even for comparing performance of journals and countries. Since its introduction, many Hirsch-type variants have been proposed to overcome perceived limitations of the original index. In this paper, using ideas from mathematical modeling, another mock h-index is proposed which may complement the h-index and give it better resolving power.     

The thermodynamic properties of liquid binary mixtures of <Emphasis Type=Italic>n</Emphasis>-alkanes: <Emphasis Type=Italic>n</Emphasis>-decane + <Emphasis Type=Italic>n</Emphasis>-hexadecane

Data on sound velocity are used for determining the density, the isobaric expansion coefficient, the isobaric and isochoric heat capacity, and the isothermal compressibility of liquid binary mixture of n-decane + n-hexadecane of three compositions in the temperature range of 298–433 K and pressure range of 0.1–100 MPa. The coefficients of Tait equation are calculated in the above-identified range of parameters. The calculation results are compared with experimental data on density. The divergence does not exceed 0.2% for the most reliable data.     

The speed of sound of <Emphasis Type=Italic>n</Emphasis>-heptane, <Emphasis Type=Italic>n</Emphasis>-octane and their binary mixtures at temperatures <Emphasis Type=Italic>T</Emphasis> = 293.15 to 523.15 K and pressures up to 60 MPa

Speeds of sound in liquid n-heptane, n-octane and their binary mixtures were measured at the temperatures T = 293.15 to 523.15 K and pressures up to 60 MPa. The pulse-echo method with a frequency of 8MHz and uncertainty of ±0.08% was used. The measured values were fitted by polinomials, as functions of temperature and pressure, and the reliability of the present results was proved by comparison with the literature data.     

<Emphasis Type=Italic>hg</Emphasis>-index: a new index to characterize the scientific output of researchers based on the <Emphasis Type=Italic>h</Emphasis>- and <Emphasis Type=Italic>g</Emphasis>-indices

To be able to measure the scientific output of researchers is an increasingly important task to support research assessment decisions. To do so, we can find several different measures and indices in the literature. Recently, the h-index, introduced by Hirsch in 2005, has got a lot of attention from the scientific community for its good properties to measure the scientific production of researchers. Additionally, several different indicators, for example, the g-index, have been developed to try to improve the possible drawbacks of the h-index. In this paper we present a new index, called hg-index, to characterize the scientific output of researchers which is based on both h-index and g-index to try to keep the advantages of both measures as well as to minimize their disadvantages.     

Generalization of <Emphasis Type=Italic>T</Emphasis> and <Emphasis Type=Italic>A</Emphasis> integrals to time-dependent materials: analytical formulations

This paper deals with the generalization of T-integral to crack growth process in viscoelastic materials. In order to implement this expression in a finite element software, a modelling form of this integral, called Aθ, is developed. The analytical formulation is based on conservative law, independent path integral, and a combination of real, virtual displacement fields, and real, virtual thermal fields introducing, in the same time, a bilinear form of free energy density F. According to the generalization of Noether’s method, the application of Gauss Ostrogradski’s theorem combined with curvilinear cracked contour, T _v is obtained. By introducing a volume domain around crack tip, the modelling expression Aθ is also defined.. Finally, the viscoelastic generalization through a thermodynamic approach, called A _v , is introduced by using a discretisation of the creep tensor according to a generalized Kelvin Voigt representation.     

Electrical impedance of ethylene-carbon monoxide/propylene-carbon monoxide (<Emphasis Type=Italic>EPEC</Emphasis>-<Emphasis Type=Italic>69</Emphasis>) thermoplastic polyketone

Electrical impedance technique was employed to investigate the electrical properties of ethylene-carbon monoxide/propylene-carbon monoxide terpolymer (EPEC-69). The measurements were performed in the frequency range 0.1–10⁵ Hz and in the temperature range 30–110 °C. The results reveal that the dielectric constant, loss factor, modulus, and ac conductivity are dependent of frequency and temperature. A Debye relaxation peak was detected in the plot of Z″ versus frequency where the activation energy was determined and found to be 1.26 eV. When the surface phenomenon effects were separated using the imaginary part of the complex admittance a second dielectric dispersion was observed in the low frequency region. Two models were proposed from the impedance measurements depending on temperature range.     

A precision <Emphasis Type=Italic>RLC</Emphasis>-meter

The MNS1100 precision RLC-meter, which operates over a wide range of frequencies and measurable impedance parameters, is described. The instrument is based on new impedance measuring principles with a reduced set of measures and methods of calibrating the measuring circuits, which enable the measurement accuracy to be increased considerably, extend the functional capabilities and automate the apparatus adjustment.     

Electrical properties of photodiodes based on <Emphasis Type="Italic">p</Emphasis>-GaSb/<Emphasis Type="Italic">p</Emphasis>-GaInAsSb/<Emphasis Type="Italic">N</Emphasis>-GaAlAsSb heterojunctions

We have studied the electrical characteristics of photodiodes based on p-GaSb/p-GaInAsSb/N-GaAlAsSb heterojunctions and investigated the mechanisms of current transfer in these heterostructures at various temperatures. A comparison of the theoretical results and experimental data showed that the tunneling charge transfer mechanism dominates at low temperatures (T < 150 K) under both forward and reverse bias conditions. The tunneling current becomes a determining factor at an electric field strength in the p-n junction of no less that 10⁵ V/cm, which is related to a small bandgap width of the materials studied and low effective masses of electrons and holes.     

Combination of <Emphasis Type=Italic>Eigenfactor</Emphasis><Superscript>TM</Superscript> and <Emphasis Type=Italic>h-</Emphasis>index to evaluate scientific journals

The h-index and Eigenfactor ^TM values of top and specialized scientific/engineering journals are tabulated and combined to provide a simple graphical representation of the journals. The information may be tailored to specific uses by respective stakeholders to aid decision making processes with regards to scholarly research and scientific journal publications.     

Gravireception in <Emphasis Type=Italic>Phycomyces Blakesleeanus</Emphasis> and <Emphasis Type=Italic>Arabidopsis Thaliana</Emphasis>: Hysteretic Behavior of Primary Reactions

The gravireception of the fungus Phycomyces blakesleeanus and seedlings of Arabidopsis thaliana is accompanied by gravity-induced absorption changes (GIACs) that occur very fast and most likely represent primary responses of gravireception. GIACs that were analyzed during parabolic flights in micro- and hypergravity invariably display hysteretic behavior. Even though the identity of the pigments generating the GIACs remain presently unknown, it is nevertheless clear that they are specific for gravireception. This is strongly suggested by the fact that hystereses loops of wild-type specimen are significant larger than of gravitropic mutants. Hystereses are largely kinetically determined, are specific for the different organisms and stimulus programs, and thus aid in characterizing the requisite transduction chains of gravireception. The fact that monocot as well as dicot plants display GIACs just in the area of highest gravitropic sensitivity at the tip supports the conclusion that gravireception is generally associated with primary reactions.     

Polaronic Effect and Its Impact on <Emphasis Type=Italic>T</Emphasis><Subscript><Emphasis Type=Italic>c</Emphasis></Subscript> for Novel Layered Superconducting Systems

The crystal lattice of a complex compound may contain a subsystem of ions with each one possessing two close equilibrium positions (double-well structure). For example, the oxygen ions in the cuprates form such a subsystem. In such a situation it is impossible to separate electronic and local vibrational motions. This leads to a large increase in the effective strength of the electron–lattice interaction, which is beneficial for pairing.     

Catalytic property of TiO<Subscript>2</Subscript>/PS complex nanoparticles prepared <Emphasis Type=Italic>via</Emphasis> a novel TSM

With an average size of 7 nm and good catalytic property under the natural light, TiO₂/PS complex nanoparticles were successfully prepared through a novel two-step method (TSM) from TiCl₄, used as both the catalyst for polymerization of styrene and Ti source, and styrene monomer and characterized by TG-DTA, XRD, IR, TEM and UV-Vis techniques. Its catalytic property was evaluated by the decolourization and degradation of dye MB solution under the natural light. From its TEM, the particles with an average size of 7 nm were observed without the separation of TiO₂ and PS phases, i.e., TiO₂/PS was hybrid material in nanosize scale. IR spectrum of TiO₂/PS showed increase of unsaturated degree and growth of the group C=O on the chain of PS and Ti–O–C coordination bond between TiO₂ and PS. The nanosize of the TiO₂/PS complex particles and the conjugated structure and polar groups of PS were advantageous to good adsorptive property and strong interaction of PS and TiO₂. And they brought multi-functions of inorganic and organic materials in the single material. Catalytic experiments indicated that the complex nanoparticles could catalytically degrade dye MB solution in 10 min under the natural light while P25 basically showed adsorptive property for MB molecules under the same conditions.     

A multifunctional Ag/PAOCG reusable substrate for <Emphasis Type="Italic">p</Emphasis>-nitrophenol reduction and SERS applications

We demonstrate a facile galvanic replacement reaction route to direct growth of silver nanoparticles (AgNPs) into porous alumina on conductive glass (PAOCG). Porous Al₂O₃ layer was prepared by using boehmite as precursor, deposited on conductive glass via spin coating, and followed by a heat treatment. PAOCG was attached firmly with a tiny sheet of steel and was then soaked in AgNO₃ solution. Ag⁺ ions in the nanopores of PAOCG adsorbed by capillarity were automatically reduced to metallic AgNPs, thus forming Ag/PAOCG. The catalytic property of Ag/PAOCG was investigated for p-nitrophenol (PNP) reduction using UV–Vis absorption spectroscopy, and the rate constant was evaluated using the pseudo-first-order kinetic model. This film catalyst could be readily regenerated and reused for up to ten times without significantly depreciate its efficiency. The SERS performance of Ag/PAOCG was investigated using aqueous crystal violet (CV) as a probe molecule. The optimum Ag/PAOCG substrate was capable of detecting as low as 10^?10 M aqueous CV. The reusability of Ag/PAOCG was achieved by heating the substrate at 400 °C for 5 min in air. This substrate could be reused for at least five cycles without significantly reduced SERS performance. Therefore, this powerful multifunctional surface can serve as a portable, durable and reusable substrate for PNP reduction and SERS applications.     

Temperature dependence of carrier mobility in undoped and gadolinium-doped <Emphasis Type=Italic>p</Emphasis>-GaSe crystals

We have studied the temperature dependence of carrier mobility (μ) in undoped and gadolinium-doped p-GaSe crystals. The results demonstrate that, in the temperature range 77–420 K, the carrier mobility in high-resistivity p-GaSe〈Gd〉 crystals increases at low temperatures as a power law. At high temperatures, μ(T) has a maximum and varies roughly as $T^{ - tfrac{3} {2}} $T^{ - tfrac{3} {2}} . In addition, μ is a nonmonotonic function of gadolinium content. The observed anomalies in the temperature dependence of carrier mobility in the crystals studied are due to partial disorder in these materials. The present experimental data can be interpreted in terms of a two-barrier energy-band model of partially disordered semiconductors.     

Thermal decomposition of trimethylamine borane as a precursor to nanocrystalline CVD BC<Subscript><Emphasis Type=Italic>x</Emphasis></Subscript>N<Subscript><Emphasis Type=Italic>y</Emphasis></Subscript> films

We have studied the kinetics of BC _x N _y chemical vapor deposition through trimethylamine borane decomposition at atmospheric pressure. The rate constant of the heterogeneous interaction between trimethylamine borane and an adsorption center has been determined to be k _s ⁰ = 2.7 × 10⁷exp(−10560/T) cm/s. The obtained kinetic parameters of the reaction fully determine the growth rate of nanocrystalline carbonitride films under kinetic control. The film thickness has been determined as a function of time, temperature, reactant concentration, and reactor dimensions.     

A methodology for Institution-Field ranking based on a bidimensional analysis: the <Emphasis Type=Italic>IFQ</Emphasis><Superscript>2</Superscript><Emphasis Type=Italic>A</Emphasis> index

The problem of comparing academic institutions in terms of their research production is nowadays a priority issue. This paper proposes a relative bidimensional index that takes into account both the net production and the quality of it, as an attempt to provide a comprehensive and objective way to compare the research output of different institutions in a specific field, using journal contributions and citations. The proposed index is then applied, as a case study, to rank the top Spanish universities in the fields of Chemistry and Computer Science in the period ranging from 2000 until 2009. A comparison with the top 50 universities in the ARWU rankings is also made, showing the proposed ranking is better suited to distinguish among non-elite universities.     

Marginal integration <Emphasis Type=Italic>M</Emphasis>-estimators for additive models

Additive regression models have a long history in multivariate non-parametric regression. They provide a model in which the regression function is decomposed as a sum of functions, each of them depending only on a single explanatory variable. The advantage of additive models over general non-parametric regression models is that they allow to obtain estimators converging at the optimal univariate rate avoiding the so-called curse of dimensionality. Beyond backfitting, marginal integration is a common procedure to estimate each component in additive models. In this paper, we propose a robust estimator of the additive components which combines local polynomials on the component to be estimated with the marginal integration procedure. The proposed estimators are consistent and asymptotically normally distributed. A simulation study allows to show the advantage of the proposal over the classical one when outliers are present in the responses, leading to estimators with good robustness and efficiency properties.     

Gravity Induced Absorption Changes in <Emphasis Type=Italic>Phycomyces blakesleanus</Emphasis> and Coleoptiles of <Emphasis Type=Italic>Zea mays</Emphasis> as Measured on the Drop Tower in Bremen (FRG)

Various spectroscopic experiments performed on the AIRBUS ZERO G in the years 2002 to 2007 clearly exhibited optical reflection changes as a result of gravitational changes (GIAC = Gravity Induced Absorption Change) in Phycomyces sporangiophores and corn coleoptiles. GIACs that occurred during flight parabolas in response to hyper- and microgravity were detected by a micro dual wavelength spectrometer (MDWS) for wavelengths pairs in the visible and the near infrared. We assume that GIACs indicate redox-changes of electron transport components such as flavins and cytochromes. Because microgravity on the AIRBUS 300 ZERO G only amounts to moderate values of ±4 ×10^− 2 g, i.e. far below sensitivity of the MDWS, we performed an experiment on the drop tower in Bremen (Germany) that generates microgravity as low as 4 ×10^− 5 g for 4.7 s. We detected small but significant GIACs during the microgravity phase, different in various specimen.