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Abstract  

In this paper, a new indicator called the performance index (p-index) is used to rank a 100 most prolific economists. The p-index strikes the best balance between activity (total citations C) and excellence (mean citation rate C/P). The surprise is that the h-index, which is now universally accepted almost as a canonical tool for research assessment of individuals, research faculties and institutions and even for comparing performance of journals and countries, is actually a poor indicator of performance.

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Journal of Thermal Analysis and Calorimetry
Authors: A. A. Abd El-Rahman, K. K. Tahoon, Abd El-Salam, M. Abousehly, Abd Elwahab, and A. El-Sharkawy

The specific heat (C p), thermal conductivity (λ), thermal diffusivity (a), and electrical conductivity (σ) were measured for polycrystalline HgS and Sb2S3 in the temperature range 300–600 K. The measurements were performed with an experimental apparatus based on a socalled flash method. The results showed that the mechanism of heat transfer is mainly due to phonons, whereas the contribution of electrons and bipolars is very small indeed. The energy gap of the samples was also calculated.

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Abstract  

The molar heat capacities C p,m of 2,2-dimethyl-1,3-propanediol were measured in the temperature range from 78 to 410 K by means of a small sample automated adiabatic calorimeter. A solid-solid and a solid-liquid phase transitions were found at T-314.304 and 402.402 K, respectively, from the experimental C p-T curve. The molar enthalpies and entropies of these transitions were determined to be 14.78 kJ mol−1, 47.01 J K−1 mol for the solid-solid transition and 7.518 kJ mol−1, 18.68 J K−1 mol−1 for the solid-liquid transition, respectively. The dependence of heat capacity on the temperature was fitted to the following polynomial equations with least square method. In the temperature range of 80 to 310 K, C p,m/(J K−1 mol−1)=117.72+58.8022x+3.0964x 2+6.87363x 3−13.922x 4+9.8889x 5+16.195x 6; x=[(T/K)−195]/115. In the temperature range of 325 to 395 K, C p,m/(J K−1 mol−1)=290.74+22.767x−0.6247x 2−0.8716x 3−4.0159x 4−0.2878x 5+1.7244x 6; x=[(T/K)−360]/35. The thermodynamic functions H TH 298.15 and S TS 298.15, were derived from the heat capacity data in the temperature range of 80 to 410 K with an interval of 5 K. The thermostability of the compound was further tested by DSC and TG measurements. The results were in agreement with those obtained by adiabatic calorimetry.

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Six, sensitive, precise and accurate methods have been developed for the determination of cefditoren pivoxil (CP). The first two methods were based on the formation of charge transfer colored complex between CP and p-chloranilic acid (p-CA) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in the concentration range of 50.00–225.00 μg mL−1 and 75.00–250.00 μg mL−1, respectively. The influence of different parameters on color formation was studied to determine optimum conditions for the visible spectrophotometric methods. The other four methods were adopted for determination of the studied drug in the presence of its acid degradation products including two spectrophotometric methods, namely, first derivative (D1) and first derivative of ratio spectra (DD1), and two chromatographic methods, namely, thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), as stabilityindicating techniques. The degradation products were identified by infrared and mass spectroscopy. All the proposed methods were validated and successfully applied for determination of CP in pure form and in pharmaceutical preparations with good recovery ranges between 99.19 and 100.62. The results obtained by applying the proposed methods were statistically analyzed and compared with those obtained by the manufacturer method, and no significant difference was found.

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The nucleotide sequence of the coat protein (CP) gene and the 3' non-translated region, in relation to aphid transmission of 7 potato tuber necrotic ringspot isolates of Potato virus Y (PVYNTN) were studied. Five isolates originated from different areas of potato fields in Hungary and two German isolates served as controls. A 5' tail of the nucleotide sequences of the CP region and 3' non-translated region (NTR) were determined. Sequence data were sent to the EMBL GeneBank Database. Homology of nucleotide and amino acid sequences were high among the studied PVY isolates. According to the characteristic regions, all isolates belonged to the PVYNTN strain. All of the tested isolates could be transmitted by the aphid Myzus persicae Sulzer to the test plant Nicotiana tabacum L. verifying the wide distribution of tuber necrotic ringspot strain in Hungary. Our data suggest that the high homology found in the CP region of the different isolates, are suitable for development of coat protein mediated resistance against PVY in commercially important host plants like, e.g. potato.

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Cereal Research Communications
Authors: Zhonghu He, Zhaohua Xu, Lanqin Xia, Xianchun Xia, Jun Yan, Yan Zhang, and Xinmin Chen

Starch properties contribute positively to the quality of both dry and fresh Chinese white noodle quality. Understanding the genetic variation of starch properties in Chinese wheats will therefore facilitate genetic improvement for noodle quality. The composition of waxy protein ( Wx ) subunits, amylose content, and Rapid Visco Analyzer (RVA) properties of a total of 260 wheat cultivars and advanced lines ( Triticum aestivum L) from four Chinese winter wheat regions were characterized. Significant variation was observed for all tested parameters except for peak time. Amylose content, peak viscosity, holding strength, and breakdown values ranged 23.1 to 33.6%, 1151 to 3522cp, 1385 to 2374cp and 192 to 1711cp, respectively. Thirty-nine Chinese wheats conferred the Wx-B1 null mutation, and significant differences in starch properties were observed between the Wx-B1 null wheats and the normal wheats. Data on both waxy protein and starch properties are needed to characterize Chinese wheat germplasm for starch quality and for noodle products. Three cultivars (Guanfeng 2, Yumai 47, and Mianyang 26) had very good starch properties and noodle quality based on our previously report. They could be used as crossing parents in breeding programs targeting for noodle quality improvement.

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Journal of Thermal Analysis and Calorimetry
Authors: Olga V. Alekseeva, Vladimir P. Barannikov, Nadezhda A. Bagrovskaya, and Andrew V. Noskov

Abstract

Polystyrene composite films with different content of C60 + C70 fullerene mix have been obtained from o-xylene solutions. The mass fraction of fullerene was varied from 0.01 to 0.1 mass%. The glass transition temperatures and specific heat capacities in range of 293–423 K have been determined for the films by DSC method. The plasticization of the polymer is observed in thermal properties of the films under influence of small fullerene additions. The values of T g and C P decrease and thermal coefficient of heat capacity b increase as fullerene content increases up to 0.02 mass%. The effect of interaction between polymer and fullerene molecules on thermal properties becomes evident at higher fullerene content in range from 0.02 to 0.1 mass%. At this the values of T g and C P increase and b coefficient decrease with increasing content of fullerene. Concentration dependence of C P and b values is less steep for polymer composite films in elastic state at temperatures above T g. Molecular interactions in the composites are discussed in view of our-self and literature data.

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In the present paper, CFD simulation is used to perform the numerical calculation of behaviours of multi-blade drag typed VAWT. The sliding grid technology, FLUENT software and PISO algorithm are involved. By taking wind power efficiency C p as the goal function, the optimal situations of multi-blade drag typed VAWT with 4 and 6 blades are conducted by CFD simulation. In this investigation, the variable parameters include the rotation rate of wind-mill ω, the blade installation angle θ and the blade width d. The results show that: the optimal working conditions for the 4-blade wind mill at the inlet wind speed 8 m/s are ω = 18 r/ min, θ = 28°, and d = 0.83 m, which induces an optimal wind power efficiency rate C p = 27.127%; the optimal working conditions for the 6-blade wind mill at the inlet wind speed 8 m/s are ω = 18 r/min, θ = 27°, and d = 0.67 m, which leads to an optimal wind power efficiency rate C p = 30.404%.

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Abstract  

Molar heat capacities (C p,m) of aspirin were precisely measured with a small sample precision automated adiabatic calorimeter over the temperature range from 78 to 383 K. No phase transition was observed in this temperature region. The polynomial function of C p,m vs. T was established in the light of the low-temperature heat capacity measurements and least square fitting method. The corresponding function is as follows: for 78 K≤T≤383 K, C p,m/J mol-1 K-1=19.086X 4+15.951X 3-5.2548X 2+90.192X+176.65, [X=(T-230.50/152.5)]. The thermodynamic functions on the base of the reference temperature of 298.15 K, {ΔH TH 298.15} and {S T-S 298.15}, were derived. Combustion energy of aspirin (Δc U m) was determined by static bomb combustion calorimeter. Enthalpy of combustion (Δc H o m) and enthalpy of formation (Δf H o m) were derived through Δc U m as - (3945.262.63) kJ mol-1 and - (736.411.30) kJ mol-1, respectively.

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Thermal properties of jojoba wax

I. Crystallization behaviour

Journal of Thermal Analysis and Calorimetry
Authors: V. González-González, R. O. Valero-Coss, and E. Campos-López

The thermal behaviour of Jojoba (Simmondsia chinensis) liquid wax was studied by differential scanning calorimetry (DSC), varying the annealing conditions. The fusion enthalpy (ΔHf) of the unannealed material was 27.1 cal/g; the relationship between heat capacity (Cp) and temperature could be expressed by the following equation:Cp=9.51×10−4 T+0.129. It was found that Jojoba wax presents four endothermic transitions (α, β, γ andδ) including fusionα, estimable at low heating rates (1 K/min); the activation energies (Ea) for transitionsα andγ were 51.18 and 64.82 Kcal/mole respectively; and it was observed that the transition temperaturesα andγ maintained a lineal relationship with the square root of the heating rate (Hr).

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