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, 16 ]. Recently, it has been greatly developed for directly determining heat capacities for various materials successfully [ 17 – 20 ]. In this article, the preparation and the crystal structure of DPFEB were reported. In addition, the molar

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researches are focused on phase transitions of (1-C 12 H 25 NH 3 ) 2 CuCl 4 , (1-C 14 H 29 NH 3 ) 2 CuCl 4 , and (1-C 16 H 33 NH 3 ) 2 CuCl 4 . However, the crystal structure, lattice potential energy, and some basic thermochemical data of (1-C 8 H 17 NH 3

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Crystal structures and thermal properties of some rare earth alkoxides with tertiary alcohols

Possible precursors for atomic layer deposition of rare earth oxides

Journal of Thermal Analysis and Calorimetry
Authors: Timo Hatanpää, Kaupo Kukli, Mikko Ritala, and Markku Leskelä

thermal analysis (SDTA) measurements and vacuum sublimation experiments. Crystal structures of four new compounds, [Y(OCEt 2 t Bu) 3 ] 2 , [La(OCEt 2 t Bu) 3 ] 2 , [Gd(OC i Pr 3 ) 3 ] 2 , and [La(OC i Pr 3 ) 3 ] 2 were solved. In addition, some ALD

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’s group at Clemson University, in order to correlate CNT’s crystal structure and chemical activity [ 6 ]. In addition, for the first time, molecular beam scattering data have been collected on CNTs in collaboration with Turro’s group at Columbia University

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Abstract  

The complex of [Nd(BA)3bipy]2 (BA = benzoic acid; bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR spectra, single crystal X-ray diffraction, and TG/DTG techniques. The crystal is monoclinic with space group P2(1)/n. The two–eight coordinated Nd3+ ions are linked together by four bridged BA ligands and each Nd3+ ion is further bonded to one chelated bidentate BA ligand and one 2,2′-bipyridine molecule. The thermal decomposition process of the title complex was discussed by TG/DTG and IR techniques. The non-isothermal kinetics was investigated by using double equal-double step method. The kinetic equation for the first stage can be expressed as dα/dt = A exp(−E/RT)(1 − α). The thermodynamic parameters (ΔH , ΔG , and ΔS ) and kinetic parameters (activation energy E and pre-exponential factor A) were also calculated.

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Abstract  

The complex (C11H18NO)2CuCl4(s) was synthesized. Chemical analysis, elemental analysis, and X-ray crystallography were used to characterize the structure and composition of the complex. Low-temperature heat-capacities of the compound were measured by an adiabatic calorimeter in the temperature range from 77 to 400 K. A phase transition of the compound took place in the region of 297–368 K. Experimental molar heat-capacities were fitted to two polynomial equations of heat-capacities as a function of the reduced temperature by least square method. The peak temperature, molar enthalpy, and entropy of phase transition of the compound were calculated to be T trs = 354.214 ± 0.298 K, Δtrs H m = 76.327 ± 0.328 kJ mol−1, and Δtrs S m = 51.340 ± 0.164 J K−1 mol−1.

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Abstract  

A new high-nitrogen complex [Cu(Hbta)2]·4H2O (H2bta = N,N-bis-(1(2)H-tetrazol-5-yl) amine) was synthesized and characterized by elemental analysis, single crystal X-ray diffraction and thermogravimetric analyses. X-ray structural analyses revealed that the crystal was monoclinic, space group P2(1)/c with lattice parameters a = 14.695(3) Å, b = 6.975(2) Å, c = 18.807(3) Å, β = 126.603(1)°, Z = 4, D c = 1.888 g cm−3, and F(000) = 892. The complex exhibits a 3D supermolecular structure which is built up from 1D zigzag chains. The enthalpy change of the reaction of formation for the complex was determined by an RD496–III microcalorimeter at 25 °C with the value of −47.905 ± 0.021 kJ mol−1. In addition, the thermodynamics of the reaction of formation of the complex was investigated and the fundamental parameters k, E, n,
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,
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, and
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were obtained. The effects of the complex on the thermal decomposition behaviors of the main component of solid propellant (HMX and RDX) indicated that the complex possessed good performance for HMX and RDX.
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Crystal structures together with enthalpies and temperatures of fusion of two substituted amino acids, N-acetylsarcosinamide (NASarA) and N-acetyl-L-isoleucinamide (NAIA), were determined by single crystal X-ray analysis and differential scanning calorimetry, respectively. The results were compared with those of some analogous amino acid derivatives previously studied. The detailed knowledge of crystallographic parameters is undoubtedly useful for discussing the thermodynamic results and rationalizing the fusion behaviour, owing to the rather poor knowledge of the molecular interactions occurring in the melt.

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The effect of certain promoters on TiO2 crystal structure transformation was studied by mean thermal and X-ray analyses. It was found that the addition of rutile nuclei and potassium, phosphorus, zinc, magnesium, and aluminium compounds to hydrated titanium dioxide before calcination process influences on the initial temperature and anatase transformation.

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Abstract  

It is well known that by the coordinated action of atoms arranged in rows and planes in the crystal lattice, the motion of charged particles such as protons, alpha particles and heavier ions can be influenced so that their range in the single crystals is considerably enhanced in low-index directions. A technique has been developed based on such enhanced penetration (channeling) of radioactive atoms (220Rn) emitted by recoil with a 100 keV energy from a224Ra point source to record channeling patterns which show the crystal structure. The radioactive recoil atoms impinging from this source on the surface of a single crystal penetrate deeper in places where their direction of impact is identical with low index crystal directions and planes. These places can be visualized by autoradiography when having first stripped a thin layer from the surface corresponding to the random range of the atoms. This technique is generally applicable in close packed crystals and gives information about the crystal structure of very thin surface layers.

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