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51.
Wolff M Pálsson GK Korelis PT Dura JA Majkrzak C Hj?rvarsson B 《J Phys Condens Matter》2012,24(25):255306
The distribution of hydrogen in Nb/Ta superlattices has been investigated by combined neutron reflectivity and x-ray scattering. We provide evidence to support that strain modulations determined with x-ray diffraction can be interpreted as modulations in hydrogen content. We show that the hydrogen concentration is modulated and favors Nb, in agreement with previous studies. We measure the concentration directly using neutron reflectivity and demonstrate no detectable change in the distribution of hydrogen with temperature, in stark contrast to previous studies. 相似文献
52.
Mohd Heikal Mohd Yunus Zahra Rashidbenam Mh Busra Fauzi Ruszymah Bt Hj Idrus Aminuddin Bin Saim 《Molecules (Basel, Switzerland)》2021,26(21)
The normal function of the airway epithelium is vital for the host’s well-being. Conditions that might compromise the structure and functionality of the airway epithelium include congenital tracheal anomalies, infection, trauma and post-intubation injuries. Recently, the onset of COVID-19 and its complications in managing respiratory failure further intensified the need for tracheal tissue replacement. Thus far, plenty of naturally derived, synthetic or allogeneic materials have been studied for their applicability in tracheal tissue replacement. However, a reliable tracheal replacement material is missing. Therefore, this study used a tissue engineering approach for constructing tracheal tissue. Human respiratory epithelial cells (RECs) were isolated from nasal turbinate, and the cells were incorporated into a calcium chloride-polymerized human blood plasma to form a human tissue respiratory epithelial construct (HTREC). The quality of HTREC in vitro, focusing on the cellular proliferation, differentiation and distribution of the RECs, was examined using histological, gene expression and immunocytochemical analysis. Histological analysis showed a homogenous distribution of RECs within the HTREC, with increased proliferation of the residing RECs within 4 days of investigation. Gene expression analysis revealed a significant increase (p < 0.05) in gene expression level of proliferative and respiratory epithelial-specific markers Ki67 and MUC5B, respectively, within 4 days of investigation. Immunohistochemical analysis also confirmed the expression of Ki67 and MUC5AC markers in residing RECs within the HTREC. The findings show that calcium chloride-polymerized human blood plasma is a suitable material, which supports viability, proliferation and mucin secreting phenotype of RECs, and this suggests that HTREC can be a potential candidate for respiratory epithelial tissue reconstruction. 相似文献
53.
54.
The First Gadolinium Carbide Fluoride: Gd2CF2 Gd2CF2, the first gadolinium carbide fluoride is prepared by reaction of stoichiometric amounts of GdF3, Gd, and C at 1250°C in sealed Ta-capsules. It is isotypic with Gd2CBr2 (space group P3 m1; a = 373.11(4) and c = 642.5(1) pm). The Gd atoms surround the C atoms octahedrally. Such Gd6C octahedra are condensed via edges to form octahedral sheets, which are separated by double slabs of F?? ions. 相似文献
55.
56.
On the System Zn/Mo/O. I. Phases and Properties of Ternary Zinc Molybdates; Crystal Structure of Zn3Mo2O9 Several ternary compounds are known in the Zn/Mo/O-system. The phases ZnMoO4, Zn2Mo3O8 and Zn3Mo2O9 are stable at 900°C. The coexistence ranges are shown in the ternary phase diagram. The structure of Zn3Mo2O9 has been determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/m (a = 7,757(1) Å, b = 7,132(1) Å, c = 8,370(2) Å, β = 117,40(1)º, Z = 2). 相似文献
57.
M. S. Yasir A. Ab Majid R. Yahaya 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(3):539-541
The main component of most building materials in Malaysia is rock. All rocks are known to contain natural radionuclides such
as 238U and 232Th series as well as 40K. In order to estimate the radiological impact to the dweller, the level of radionuclides present in various building materials
available in Malaysia were analyzed using γ-spectrometry. The radiation hazard indexes were calculated based on the above results. The results showed that the activity
concentration of natural radionculides 238U, 232Th, 40K was between 19.0–42.2 Bq/kg, 16.5–28.8 Bq/kg and 243.3–614.2 Bq/kg, respectively. On the whole, the radionuclides concentration
was still below the global average of 50 Bq/kg, 50 Bq/kg and 500 Bq/kg for 238U, 232Th, and 40K, respectively The radiation hazard indexes of the building materials were also lower than the maximum value suggested. 相似文献
58.
Thermal Behaviour and Crystal Structure of YAl3Cl12 We determined the thermodynamic data of YAl3Cl12 ΔH = ?739.9 ± 3 kcal/mol and S = 136.1 ± 4 cal/K · mol by total pressure measurements and ΔH = ?739.1 ± 1.6 kcal/mol by solution calorimetry. Using DTA-investigations we established the phase diagram in the system AlCl3–YCl3. The crystal structure was refined on the basis of single crystal data (P31 12; Z = 3; a = 1 046.8(2); c = 1 562.3(3) pm). 相似文献
59.
M. Akbar Ali Hjh Junaidah Hj Abu Bakar A.H. Mirza S.J. Smith L.R. Gahan Paul V. Bernhardt 《Polyhedron》2008
Complexes of general formula, [M(isa-sme)2] · n(solvate) [M = Ni2+, Cu2+, Zn2+, Cd2+; isa-sme = monoanionic form of the Schiff base formed by condensation of isatin with S-methyldithiocarbazate; n = 1 or 1.5; solvate = MeCN, DMSO, MeOH or H2O] have been synthesized and characterized by a variety of physicochemical techniques. An X-ray crystallographic structure determination of the [Ni(isa-sme)2] · MeCN complex reveals a six-coordinate, distorted octahedral geometry. The two uninegatively charged, tridentate, Schiff base ligands are coordinated to the nickel(II) ion meridionally via the amide O-atoms, the azomethine N-atoms and the thiolate S-atoms. By contrast, the crystal structure of [Zn(isa-sme)2] · MeOH shows a four-coordinate distorted tetrahedral geometry. The two dithiocarbazate ligands are coordinated as N, S bidentate chelates with the amide O-atom not coordinated. The structure of the copper(II) complex [Cu(isa-sme)2] · DMSO is complicated and comprises two different complexes in the asymmetric unit, one four- and the other five-coordinate. The four-coordinate copper(II) has a distorted (flattened) tetrahedral geometry as seen in the Zn(II) analogue whereas the five-coordinate copper(II) has a distorted square-pyramidal geometry with one ligand coordinated to the copper(II) ion as a tridentate (N, S, O) ligand and the other coordinated as a bidentate N, S chelate. EPR spectroscopy indicates that in solution only one form is present, that being a distorted tetrahedral complex. 相似文献
60.
Nizam M. El-Ashgar Issa M. El-Nahhal Mona A. Ahmed Asmah A. Abu Shaweesh Mohamed M. Chehimi 《Journal of the Iranian Chemical Society》2018,15(10):2325-2338
Immobilized-polysiloxane (diamine-thiol) tetraethylacetate, P-(NN-S)-TEA (where P represents [Si–O]n polysiloxane network), was synthesized using one-pot reaction of tetraethylorthosilicate (TEOS) with 3-(ethylenediaminetriethylacetate)propyltrimethoxysilane and 3-thiolethylacetatepropyltrimethoxysilane in the presence of cetyl trimethylammonium bromide (CTAB) as a surfactant. Its ethylenediamine and diethylenetriamine modified polysiloxane (diamine-thiol)-tetrakis(N-2-aminoethylacetamide), P-(NN-S)-TEA-NN, and polysiloxane (diamine-thiol)-tetrakis(N-diethylenediamineacetamide), P-(NN-S)-TEA-NNN chelating ligand systems were also obtained. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopic (XPS), and thermogravimetric analysis (TGA) techniques have been used for establishing their structures. An elemental CHNX combustion analyzer was used to determine the mass fractions of carbon, hydrogen, nitrogen, and sulfur of samples. The metal uptake capacities results showed that the modified polysiloxane ligand systems exhibited high capacities for the uptake of divalent metal ions in the following order: Cu2+> Pb2+> Ni2+> Co2+. 相似文献