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  • Author or Editor: R. Hu x
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A survey was carried out in three stud farms with grazing animals, in order to gather data on the prevalence and clinical manifestation of, and the fly species involved in, traumatic myiasis of horses in Hungary. This parasitic disease was recorded in each farm. On the whole, 9.0% (14) of the inspected horses were infested with fly larvae. The affected horses had one infested lesion only, located at the mucosa of the vulva or the vaginal vestibule. The clinical symptoms depended on the age of infestation. Wohlfahrtia magnifica (Diptera: Sarcophagidae) was the only myiasis-causing fly species identified. It was assumed that unknown volatile chemicals might be responsible for the attraction of gravid females to the undamaged vulvar region. These odours are supposed to be produced during different physiological and/or pathological events associated with oestrus, prolonged puerperal period or inflammation of tissues. Daily inspection of grazing horses and early treatment of the affected areas are needed to avert significant damage to the infested horses.

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Abstract

According to our initial assumption, there would be two characteristic strategies for Romani catching up. One strategy is to lift the Romanies out of poverty and bring their living conditions closer to the average living conditions of the majority society. According to the other strategy, Romanies create a national minority in the majority society. It should be supported so that the members of the community could preserve their national characteristics and exercise their minority rights. By reviewing the literature (e.g., Armillei 2014; Boscoboinik & Giordano 2008; Ladányi & Szelényi 2016) we searched in which country which strategies are being followed by current governments. The result is that these strategies coexist within a country and are increasingly intermingled according to existing governments. The reason for this phenomenon is the recent changes in Romani societies and the emergence of new middle classes. There are both economic and cultural conditions for emerging these middle classes. A successful Romani strategy has to contain therefore, both economic and cultural actions. The governments of the region must contribute not only to the catching-up of the Romanies but also to the formation of their Romani middle classes.

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The turbulence intensity is an important feature of the turbulent airflow and draught sensation in ventilated rooms. The turbulence is often measured with hot-wire (in fluid mechanics applications) and hot-sphere sensors (in indoor air comfort investigations). In this paper the turbulence was measured with hot-wire and hot-sphere sensors in a full-scale single office room based on air speed measurements. Isothermal air injection was applied and the measurements were conducted on eight different inlet volume flow rates. The two applied sensors resulted two independent samples, which were evaluated with different statistical methods. The results showed that there was not significant difference between the standard deviation and average of the measured samples. Thus, the two sensors statistically gave the same results on probability level 95%.

The referred international standards suggest an average turbulence intensity 40% for draught comfort design in mixing ventilation. The results showed that most of the measured turbulence intensities were less than the recommended standard turbulence intensity.

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Abstract  

The thermal decomposition characteristics of1,7-diazido-2,4,6-trinitrazaheptane (DATH) and multi-component systems containing DATH were studied by using DSC, TG and DTG techniques. Three –NO2 groups in the DATH molecule break away first from the main chain when DATH is heated up to 200C. Following this process, the azido groups and the residual molecule decompose rapidly to release a great deal of heat within a short time. In the multi-component systems, DATH undergoes a strong interaction with the binder of the double-base propellant and a weak interaction with RDX. The burning rates of the two propellants were determined by using a Crawford bomb. The results showed that the burning rate rises by about 19–66% when 23.5%DATH is substituted for RDX in a minimum smoke propellant. Meanwhile, the N2 level in the combustion gases is enhanced, which is valuable for a reduction of the signal level of the solid propellant.

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The title compound 3,3-dinitroazetidinium (DNAZ) 3,5-dinitrosalicylate (3,5-DNSA) was prepared and the crystal structure has been determined by a four-circle X-ray diffractometer. The thermal behavior of the title compound was studied under a non-isothermal condition by DSC and TG/DTG techniques. The kinetic parameters were obtained from analysis of the TG curves by Kissinger method, Ozawa method, the differential method and the integral method. The kinetic model function in differential form and the value of E a and A of the decomposition reaction of the title compound are f(α)=4α3/4, 130.83 kJ mol−1 and 1013.80s−1, respectively. The critical temperature of thermal explosion of the title compound is 147.55 °C. The values of ΔS , ΔH and ΔG of this reaction are −1.35 J mol−1 K−1, 122.42 and 122.97 kJ mol−1, respectively. The specific heat capacity of the title compound was determined with a continuous C p mode of mircocalorimeter. Using the relationship between C p and T and the thermal decomposition parameters, the time of the thermal decomposition from initiation to thermal explosion (adiabatic time-to-explosion) was obtained.

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A method for estimating the critical temperatures (T b) of thermal explosion for energetic materials is derived from Semenov’s thermal explosion theory and the non-isothermal kinetic equation dα/dt=A 0 T B f(α)e−E/RT using reasonable hypotheses. The final formula of calculating the value of T b is
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\left( {\frac{B} {{T_b }} + \frac{E} {{RT_b^2 }}} \right)$$ \end{document}
(T bT e0=1. The data needed for the method, E and T e0, can be obtained from analyses of the non-isothermal DSC curves. When B=0.5 the critical temperature (T b) of thermal explosion of azido-acetic-acid-2-(2-azido-acetoxy)-ethylester (EGBAA) is determined as 475.65 K.
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Abstract  

The thermal decomposition behaviour of the complexes of rare earth metals with histidine: RE(His)(NO3)3 H2O (RE=La—Nd, Sm—Lu and Y; His=histidine) was investigated by means of TG-DTG techniques. The results indicated that the thermal decomposition processes of the complexes can be divided into three steps. The first step is the loss of crystal water molecules or part of the histidine molecules from the complexes. The second step is the formation of alkaline salts or mixtures of nitrates with alkaline salts after the histidine has been completely lost from the complexes. The third step is the formation of oxides or mixtures of oxides with alkaline salts. The results relating to the three steps indicate that the stabilities of the complexes increase from La to Lu.

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Abstract  

The solid complexes of Cr(NO3)3 with L-α-amino acids (AA=Val, Leu, Thr, Arg, Phe and Try) have been prepared in 95% alcoholic, the compositions of which were identified as the general formula Cr(AA)2(NO3)32H2O by elemental and chemical analyses. The bonding characteristics of the title complexes were characterized by IR, indicating that nitrogen and oxygen atoms in the ligands coordinated to Cr3+ in a bidentate fashion. With the aid of TG-DTG and IR techniques, the complexes were subjected to thermal decomposition in an atmosphere of oxygen, presuming that the decompositions of the complexes consist of two steps and the complexes were decomposed into chromium hemitrioxide after undergoing dehydration and skeleton splitting of the complexes. The constant volume energies of combustion of the complexes were determined by a RBC-P type rotating-bomb calorimeter. According to Hess's law, the standard enthalpies of formation of the complexes were calculated as (-1831.404.40), (-2542.036.13), (-1723.813.99), (-2224.313.02), (-2911.616.53) and (-659.327.42) kJ mol-1, respectively.

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Abstract  

Solid complexes of M(His)2Cl2 nH2O (M=Mn, Co, Ni, Cu) of MnCl26H2O, CoCl26H2O, NiCl26H2O, CuCl22H2O and L-α-histidine (His) have been prepared in 95% ethanol solution and characterized by elemental analyses, chemical analyses, IR and TG-DTG. The constant-volume combustion energies of the complexes have been determined by a rotating-bomb calorimeter. And the standard enthalpies of formation of the complexes have been calculated as well.

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