scholarly journals Properties of PbS: Ni2+ Nanocrystals in Thin Films by Chemical Bath Deposition

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
O. Portillo Moreno ◽  
L. A. Chaltel Lima ◽  
M. Chávez Portillo ◽  
S. Rosas Castilla ◽  
M. Zamora Tototzintle ◽  
...  

The growth of nanocrystalline PbS films by chemical bath deposition (CBD) onto glass at temperature is presented in this research. We report on the modification of structural, optical, and electrical nanostructures due to in situ Ni-doping. The morphological changes of the layers were analyzed using SEM, AFM, and TEM. XRD spectra displayed peaks at 2θ = [26.00, 30.07, 43.10, 51.00, 53.48], indicating growth on the zinc blende face. The grain size determined by X-rays diffraction of the undoped samples was 36 nm, whereas with the doped sample was 3.2–5 nm. By TEM, the doped PbS was found crystalline films in the range 3.5–5 nm. Optical absorption (OA), and forbidden bandgap energy shift disclose a shift in the range 2.1–3.8 eV. Likewise, the dependence of with the radius size and interplanar distance of the lattice is discussed. Raman spectroscopy (RS) exhibited an absorption band 135 cm−1 displaying only a PbS ZB structure. The thermal energy for the films was determined from the slope of dark conductivity (DC) and the energy was estimated to be 0.15 to 0.5 eV.

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
R. Palomino-Merino ◽  
O. Portillo-Moreno ◽  
L. A. Chaltel-Lima ◽  
R. Gutiérrez Pérez ◽  
M. de Icaza-Herrera ◽  
...  

Nanocrystalline PbS thin films were prepared by Chemical Bath Deposition (CBD) at 40 ± 2°C onto glass substrates and their structural and optical properties modified by in-situ doping with Hg. The morphological changes of the layers were analyzed using SEM and the X-rays spectra showing growth on the zinc blende (ZB) face. The grain size determined by using X-rays spectra for undoped samples was found to be~36 nm, whereas with the doped sample was 32–20 nm. Optical absorption spectra were used to calculate theEg, showing a shift in the range 1.4–2.4 eV. Raman spectroscopy exhibited an absorption band~135 cm−1displaying only a PbS ZB structure.


Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1239
Author(s):  
Manuel Ramos ◽  
Félix Galindo-Hernández ◽  
Brenda Torres ◽  
José Manuel Domínguez-Esquivel ◽  
Martin Heilmaier

We report the thermal stability of spherically shaped cobalt-promoted molybdenum disulfide (Co/MoS2) nano-catalysts from in-situ heating under electron irradiation in the scanning transmission electron microscope (STEM) from room temperature to 550 °C ± 50 °C with aid of Fusion® holder (Protochip©, Inc.). The catalytic nanoparticles were synthesized via a hydrothermal method using sodium molybdate (Na2MoO4·2H2O) with thioacetamide (CH3CSNH2) and cobalt chloride (CoCl2) as promoter agent. The results indicate that the layered molybdenum disulfide structure with interplanar distance of ~0.62 nm remains stable even at temperatures of 550 °C, as observed in STEM mode. Subsequently, the samples were subjected to catalytic tests in a Robinson Mahoney Reactor using 30 g of Heavy Crude Oil (AGT-72) from the golden lane (Mexico’s east coast) at 50 atm using (ultrahigh purity) UHP hydrogen under 1000 rpm stirring at 350 °C for 8 h. It was found that there is no damage on the laminar stacking of Co/MoS2 with temperature, with interlayer spacing remaining at 0.62 nm; these sulfided catalytic materials led to aromatics rise of 22.65% and diminution of asphaltenes and resins by 15.87 and 3.53%, respectively.


2013 ◽  
Vol 712-715 ◽  
pp. 293-297
Author(s):  
Li Li

Pt/Bi3.15Nd0.85Ti3O12(BNT)/Pt ferroelectric capacitors were monitored using in situ X-ray irradiation with 10 keV at BL14B1 beamline (Shanghai Synchrotron Radiation Facility). BL14B1 combined with a ferroelectric analyzer enabled measurements in situ of electrical performance. The hysteresis curve (PE) of distortion depended on the polarization during irradiation, but the diffracted intensities of the (117) peak did not change in the beginning. ThePEcurve had a negligible change from 2.09×109Gy to 4.45×109Gy. Finally, bothPrandPr+very rapidly increased, but the intensities of (117) decreased. The hysteresis loops were remarkably deformed at the maximum total dose of 4.87×109Gy.


2007 ◽  
Vol 130 ◽  
pp. 7-14 ◽  
Author(s):  
Andrew N. Fitch

The highly-collimated, intense X-rays produced by a synchrotron radiation source can be harnessed to build high-resolution powder diffraction instruments with a wide variety of applications. The general advantages of using synchrotron radiation for powder diffraction are discussed and illustrated with reference to the structural characterisation of crystalline materials, atomic PDF analysis, in-situ and high-throughput studies where the structure is evolving between successive scans, and the measurement of residual strain in engineering components.


Author(s):  
Rosalba Ciranni ◽  
Donata Pangoli ◽  
Valentina Giuffra ◽  
DAvide Caramella ◽  
Edda Bresciani ◽  
...  

Eighty-five Egyptian mummies belonging to different dynastic periods and collected in a number of Italian museums, have been censed and submitted for paleopathological research. In most cases the presence of bandages required the application of X- rays and computed axial tomography (CAT). Fifty-two mummies have been studied in situ with Xrays; twelve with CAT scanning. Technical problems kept us from investigating eleven of the censed mummies. In a few cases it was possible to perform autopsies, endoscopy, or histological studies. The mummies submitted for X- rays were divided into two groups: The first group thirty-six mummies studied by the team of Paleopathology-Egyptology of the University of Pisa were studied for the first time. The second group was composed of twenty-six mummies studied elsewhere in Italy. Those results also have been included in the Anubi Project database.


Author(s):  
Weinong W. Chen ◽  
Matthew C. Hudspeth ◽  
Ben Claus ◽  
Niranjan D. Parab ◽  
John T. Black ◽  
...  

Split Hopkinson or Kolsky bars are common high-rate characterization tools for dynamic mechanical behaviour of materials. Stress–strain responses averaged over specimen volume are obtained as a function of strain rate. Specimen deformation histories can be monitored by high-speed imaging on the surface. It has not been possible to track the damage initiation and evolution during the dynamic deformation inside specimens except for a few transparent materials. In this study, we integrated Hopkinson compression/tension bars with high-speed X-ray imaging capabilities. The damage history in a dynamically deforming specimen was monitored in situ using synchrotron radiation via X-ray phase contrast imaging. The effectiveness of the novel union between these two powerful techniques, which opens a new angle for data acquisition in dynamic experiments, is demonstrated by a series of dynamic experiments on a variety of material systems, including particle interaction in granular materials, glass impact cracking, single crystal silicon tensile failure and ligament–bone junction damage.


2021 ◽  
Vol 3 (1) ◽  
pp. 11-23
Author(s):  
Alexander I. Dorokhin ◽  
Alexander I. Krupatkin ◽  
Anastasia A. Adrianova ◽  
Vladimir I. Khudik ◽  
Dmitriy S. Sorokin ◽  
...  

Background.Fractures of the distal leg bones in children, due to the peculiarities of localization, the presence of a growth zone, the proximity of the joint and the involvement of the ligamentous apparatus in the pathological process, present a difficult problem in the choice of treatment and rehabilitation.Aims:In order to our aims we create the diagnostic and treatment algorithm in the system of early rehabilitation after fractures in the distal part of the shin bone in adolescence.Methods.Our clinical investigation based on the treatment of 56 patients in the age 817 years. Cohort of patients consist from three age groups: 811 years (n=13), 1214 years (n=28) and 1517 years (n=15). Examination was done with X-rays, CT and Ultrasound, specialy in the cases where the damage of ligamentous apparatus was suspicious. The main method of treatment was surgical osteosynthesis by pins, plates and screws. In the rehabilitation period the legs were immobilized by Plaster of Paris for 46 weeks.Results.In majority of cases the outcomes in the period of 68 weeks after trauma were good and satisfactory. The method of laser Doppler fluometry was performed in 16 cases in follow up period after trauma for examination of the regional blood circulation as a argumentation of regeneration process.Conclusion.The different choice in treatment of compound fractures of the distal part of the shin bones according to morphological changes in adolescence permits to aid good results in majority of caces.


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