Explanation of the structural changes in the Si : H thin films by monohydride cluster formation

AbstractRetention of the enhanced properties reported for nanograined metallic systems requires that the nanostructure be insensitive to temperature and deformation. In situ transmission electron microscopy annealing experiments were employed to investigate the structural changes associated with the formation of micron-sized grains in nanograined evaporated gold thin films. This abnormal grain growth occurs randomly throughout the film. Twinning but not dislocation slip occurs in the growing grains until the grain size is in the hundreds of nanometer range. The twins appear to hinder growth and for grain growth to continue the twins must either be annihilated or be able to grow with the grain concurrently.

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Influence of the Para-Substituent in Lanthanoid Complexes of Bistetrazole Substituted Calix[4]arenes

10.26434/chemrxiv.9255209 ◽

2019 ◽

Author(s):

Rene Z.H. Phe ◽

Brian Skelton ◽

Massimiliano Massi ◽

Mark Ogden

Keyword(s):

Structural Changes ◽

Cluster Formation ◽

Ammonium Cation ◽

Ammonium Salts ◽

X Ray Diffraction ◽

One Dimensional ◽

X Ray ◽

Mononuclear Complexes ◽

Scattering Measurements ◽

The Impact

5,11,17,23-Tetra-tert-butyl-25,27-dihydroxy-26,28-bis(tetrazole-5-ylmethoxy)calix[4]arene has been reported to form remarkable Ln19 and Ln12 elongated clusters, upon addition of aqueous ammonium carboxylates. The impact of the para substituent on lanthanoid cluster formation has been studied by synthesising two new bis-tetrazole calixarenes, with p-H, and p-allyl substituents. Solution phase dynamic light scattering measurements of the reaction mixtures indicated that clusters are not formed with the p-H and p-allyl derivatives, in contrast with the behaviour of the t-butyl analogue. Lanthanoid complexes of the p-H and p-allyl calixarenes were characterised by single crystal X-ray diffraction, and were found to form mononuclear complexes, linked to form a one-dimensional coordination polymer for the p-allyl system. All of the complexes were isolated as ammonium salts, with ammonium cation included in the calixarene cavity in most cases. It is concluded that the nature of the para substituent has a profound impact on the lanthanoid cluster formation process, and derivatives with more subtle structural changes will be required to determine if additional lanthanoid “bottlebrush” clusters can be isolated.

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THE STRUCTURAL CHANGES OF THE Sn(y)OX THIN FILMS UNDER INFLUENCE OF HEAT TREAMENT

APPC 2000 ◽

10.1142/9789812811523_0126 ◽

2001 ◽

Author(s):

V. VONG

Keyword(s):

Thin Films ◽

Structural Changes

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Bandgap Engineering of Bilayer Ge/CdS Thin Films via Interlayer Diffusion under Different Annealing Temperatures

Journal of Nanomaterials ◽

10.1155/2019/8384794 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Faheem Amin ◽

Syedah Afsheen Zahra ◽

Muhammad Sultan ◽

Sajjad Hussain Mirza ◽

Fahad Azad

Keyword(s):

Thin Films ◽

Glass Substrate ◽

Structural Changes ◽

Annealing Temperature ◽

Thermal Evaporation ◽

Rutherford Backscattering ◽

Bandgap Engineering ◽

Thermal Evaporation Method ◽

Annealing Temperatures ◽

Cds Thin Films

Bilayer thin films of Ge/CdS have been deposited on a glass substrate through thermal evaporation method. The obtained Ge/CdS samples were annealed at temperatures up to 400°C to observe the resulting effect on the structural changes in the film. The bandgap of the annealed films was found to increase with increasing annealing temperature which can be attributed to the increased interlayer diffusion. The interlayer diffusion was found to take effect above a temperature of 300°C which was confirmed by the Rutherford backscattering technique. Complementary XPS was done to investigate the surface stoichiometry of the bilayers.

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Direct observation of oxygen-vacancy formation and structural changes in Bi2WO6 nanoflakes induced by electron irradiation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.141 ◽

2019 ◽

Vol 10 ◽

pp. 1434-1442 ◽

Cited By ~ 1

Author(s):

Hong-long Shi ◽

Bin Zou ◽

Zi-an Li ◽

Min-ting Luo ◽

Wen-zhong Wang

Keyword(s):

Electron Irradiation ◽

Oxygen Vacancies ◽

Structural Changes ◽

Cluster Formation ◽

Energetic Electron ◽

Structural Evolution ◽

Formation Mechanisms ◽

Tungsten Oxides ◽

Transmission Electron ◽

Oxygen Vacancy Formation

The prominent role of oxygen vacancies in the photocatalytic performance of bismuth tungsten oxides is well recognized, while the underlying formation mechanisms remain poorly understood. Here, we use the transmission electron microscopy to investigate the formation of oxygen vacancies and the structural evolution of Bi2WO6 under in situ electron irradiation. Our experimental results reveal that under 200 keV electron irradiation, the breaking of relatively weak Bi–O bonds leads to the formation of oxygen vacancies in Bi2WO6. With prolonged electron irradiation, the reduced Bi cations tend to form Bi clusters on the nanoflake surfaces, and the oxygen atoms are released from the nanoflakes, while the W–O networks reconstruct to form WO3. A possible mechanism that accounts for the observed processes of Bi cluster formation and oxygen release under energetic electron irradiation is also discussed.

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Agonist-evoked inositol trisphosphate receptor (IP3R) clustering is not dependent on changes in the structure of the endoplasmic reticulum

Biochemical Journal ◽

10.1042/bj20051130 ◽

2006 ◽

Vol 394 (1) ◽

pp. 57-66 ◽

Cited By ~ 32

Author(s):

Mark Chalmers ◽

Michael J. Schell ◽

Peter Thorn

Keyword(s):

Endoplasmic Reticulum ◽

Protein Interactions ◽

Cell Activation ◽

Structural Changes ◽

Fluorescent Protein ◽

Cluster Formation ◽

Yellow Fluorescent Protein ◽

Resting Cells ◽

Trisphosphate Receptor ◽

Er Membrane

The size and number of IP3R (inositol 1,4,5-trisphosphate receptor) clusters located on the surface of the ER (endoplasmic reticulum) is hypothesized to regulate the propagation of Ca2+ waves in cells, but the mechanisms by which the receptors cluster are not understood. Using immunocytochemistry, live-cell imaging and heterologous expression of ER membrane proteins we have investigated IP3R clustering in the basophilic cell line RBL-2H3 following the activation of native cell-surface antigen receptors. IP3R clusters are present in resting cells, and upon receptor stimulation, form larger aggregates. Cluster formation and maintenance required the presence of extracellular Ca2+ in both resting and stimulated cells. Using transfection with a marker of the ER, we found that the ER itself also showed structural changes, leading to an increased number of ‘hotspots’, following antigen stimulation. Surprisingly, however, when we compared the ER hotspots and IP3R clusters, we found them to be distinct. Imaging of YFP (yellow fluorescent protein)–IP3R transfected in to living cells confirmed that IP3R clustering increased upon stimulation. Photobleaching experiments showed that the IP3R occupied a single contiguous ER compartment both before and after stimulation, suggesting a dynamic exchange of IP3R molecules between the clusters and the surrounding ER membrane. It also showed a decrease in the mobile fraction after cell activation, consistent with receptor anchoring within clusters. We conclude that IP3R clustering in RBL-2H3 cells is not simply a reflection of bulk-changes in ER structure, but rather is due to the receptor undergoing homotypic or heterotypic protein–protein interactions in response to agonist stimulation.

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Improved Biodegradable Radiation Cured Polymeric Film Prepared from Chitosan-Gelatin Blend

Journal of Applied Chemistry ◽

10.1155/2016/5373670 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Zinia Nasreen ◽

Mubarak A. Khan ◽

A. I. Mustafa

Keyword(s):

Thin Films ◽

Fourier Transform ◽

Soil Degradation ◽

Structural Changes ◽

Xrd Analysis ◽

Gamma Dose ◽

Ftir Studies ◽

The Stability ◽

Degradation Properties ◽

Scanning Electron

The mechanical, thermal, swelling, and release properties of chitosan-gelatin (CG) films have been investigated in order to verify the influence of UV and gamma radiation on the stability of the films. Thin films of chitosan and gelatin (1 : 3, w/w) that were radiated with 100 krad of gamma dose showed the best performance and the TS values reached 25, 45, and 49 MPa, respectively, for chitosan, gelatin, and blend. The corresponding highest TS values were 23, 42, and 45 MPa, respectively, for 10 passes of UV radiation. The effect of radiation over gelatin, chitosan, and CG blend caused modification in the arrangement of molecules in the crystal lattice that is significant by XRD analysis. Surfaces of the films were also investigated by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) studies further revealed structural changes of the films. These changes were attributed to understanding the behavior of the irradiated chitosan, gelatin, and CG blend on application of thermal energy using DSC and TGA studies, water uptake of the films in aqueous medium, and soil degradation properties to observe the best possibility for its application.

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