The Observations of Paramagnetic Centers in Tellurite Glasses

AbstractThis is the first report of ESR observations of three distinct paramagnetic centers in TeO29 glasses. One center is intrinsic to the glass and the other two are induced by KrFexcimer-laser radiation. The intrinsic center with a broad ESR spectrum is tentatively identified as an oxygen-associated hole center. One radiation-induced center fades slowly at room temperature; its proposed structure is that of an electron trapped in a diffuse orbital associated with a modifier ion. The other radiation-induced center is stable at room temperature and corresponds to the Vo· center observed in crystalline paratellurite.

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New Phosphorus Oxygen Hole Center in Γ-Irradiated SiO2:P2O5 Optical Fiber

MRS Proceedings ◽

10.1557/proc-61-339 ◽

1985 ◽

Vol 61 ◽

Cited By ~ 5

Author(s):

H. Kawazoe ◽

M. Kohketsu ◽

Y. Watanabe ◽

K. Shibuya ◽

K. Muta

Keyword(s):

Optical Absorption ◽

Optical Fiber ◽

Room Temperature ◽

Hole Center ◽

Paramagnetic Centers ◽

Γ Irradiation ◽

Electron Center ◽

Oxygen Hole ◽

New Type ◽

Hole Centers

ABSTRACTThe formation of paramagnetic centers upon γ-irradiation was examined for the silica based waveguides doped with P2O5 by using ESR and optical absorption. The centers inherent in SiO2 glasses such as Si-E′ and OHC were found to be replaced with P-related centers such as phosphorus oxygen hole centers and phosphorus electron center by introducing a small amount of P2O5. New type of POHC was detected especially in the glass with [P2O5] of 1.3 mol % at 77K, which was assumed to be a precursor of the POHC stable at room temperature. The correlation between γ-induced loss-increase and the formation of these defects was examined.

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Radiotherapy Can Cause Haemostasis in Bleeding Skin Malignancies

Case Reports in Medicine ◽

10.1155/2012/168681 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Helena Sung-In Jang ◽

Andrew Spillane ◽

Frances Boyle ◽

Gerald Fogarty

Keyword(s):

The Other ◽

First Report ◽

Palliative Intent ◽

Radiation Induced

Radiotherapy (RT) can cause haemostasis in select cases of malignant bleeding. We present two cases where RT was used to prevent fatal exsanguination from bleeding skin malignancies. Treatment was with radical intent in one case and palliative intent in the other. The dose used in both cases was 20 Gray (Gy) in 5 fractions. To our knowledge, this is the first report of radiation-induced haemostasis in bleeding skin malignancies.

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Electron microscope studies of the plastic deformation of ternary alloys based on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178732 ◽

1990 ◽

Vol 48 (4) ◽

pp. 1120-1120

Author(s):

R. Haswell ◽

U. Bangert ◽

P. Charsley

Keyword(s):

Plastic Deformation ◽

Electron Microscope ◽

Room Temperature ◽

Stacking Faults ◽

The Other ◽

Ternary Alloys ◽

Dislocation Mobility ◽

Semiconducting Materials ◽

Micro Indentation

A knowledge of the behaviour of dislocations in semiconducting materials is essential to the understanding of devices which use them . This work is concerned with dislocations in alloys related to the semiconductor GaAs . Previous work on GaAs has shown that microtwinning occurs on one of the <110> rosette arms after indentation in preference to the other . We have shown that the effect of replacing some of the Ga atoms by Al results in microtwinning in both of the rosette arms.In the work to be reported dislocations in specimens of different compositions of Gax Al(1-x) As and Gax In(1-x) As have been studied by using micro indentation on a (001) face at room temperature . A range of electron microscope techniques have been used to investigate the type of dislocations and stacking faults/microtwins in the rosette arms , which are parallel to the [110] and [10] , as a function of composition for both alloys . Under certain conditions microtwinning occurs in both directions . This will be discussed in terms of the dislocation mobility.

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HAYNES STELLITE ALLOY No. 98M2

Alloy Digest ◽

10.31399/asm.ad.co0022 ◽

1960 ◽

Vol 9 (7) ◽

Keyword(s):

Fracture Toughness ◽

Compressive Strength ◽

Physical Properties ◽

Room Temperature ◽

Base Alloy ◽

Heat Treating ◽

The Other ◽

Stellite Alloy ◽

Cobalt Base Alloy ◽

Cobalt Base

Abstract HAYNES STELLITE 98M2 Alloy is a cobalt-base alloy having higher compressive strength and higher hardness than all the other cobalt-base alloys at room temperature and in the red heat range. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on heat treating, machining, and joining. Filing Code: Co-22. Producer or source: Haynes Stellite Company.

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The Reactivity of Different Active Forms of Sodium Carbonate with Respect to Sulfur Dioxide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922302 ◽

1992 ◽

Vol 57 (11) ◽

pp. 2302-2308

Author(s):

Karel Mocek ◽

Erich Lippert ◽

Emerich Erdös

Keyword(s):

Thermal Decomposition ◽

Liquid Phase ◽

Sulfur Dioxide ◽

Specific Surface ◽

Surface Area ◽

Sodium Carbonate ◽

Room Temperature ◽

Active Form ◽

The Other ◽

Kinetics Of

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.

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Exchange-spring mechanism and Griffiths-like phase in room-temperature magnetoelectric Ni–BaTiO3 composites

Materials Advances ◽

10.1039/d1ma00264c ◽

2021 ◽

Author(s):

Ramany Revathy ◽

Nandakumar Kalarikkal ◽

Manoj Raama Varma ◽

Kuzhichalil Peethambharan Surendran

Keyword(s):

Room Temperature ◽

First Report ◽

Magnetoelectric Composites ◽

Exchange Spring ◽

Spring Mechanism

This is the first report on the occurrence of the exchange spring mechanism and a Griffiths-like phase in Ni–BaTiO3 magnetoelectric composites with 0–3 and 1–3 connectivity.

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Organophotoredox-Catalyzed C–H Alkylation of Imidazoheterocycles with Malonates: Total Synthesis of Zolpidem

Synthesis ◽

10.1055/s-0040-1706103 ◽

2020 ◽

Author(s):

Narendra R. Chaubey ◽

Anant R. Kapdi ◽

Biswanath Maity

Keyword(s):

Total Synthesis ◽

Room Temperature ◽

Drug Molecule ◽

Bond Functionalization ◽

First Report ◽

Mild Conditions ◽

The Past ◽

Hypnotic Drug ◽

Free Environment

AbstractOrganophotocatalytic C–H bond functionalization has attracted a lot of attention in the past several years due to the possibility of catalyzing reactions in a metal- and peroxide-free environment. Continuing on these lines, an organophotoredox-catalyzed C–H functionalization of imidazo[1,2-a]pyridines and related heterocycles with bromomalonates under mild conditions is reported, providing excellent yields of the products at room temperature. This is the first report involving malonates as coupling partners leading to the synthesis of a range of functionalized products including total synthesis of zolpidem, a sedative-hypnotic drug molecule.

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Radiation-Induced Asymmetric Grafting of Different Monomers into Base Films to Prepare Novel Bipolar Membranes

Molecules ◽

10.3390/molecules26072028 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2028

Author(s):

Shin-ichi Sawada ◽

Yasunari Maekawa

Keyword(s):

Acrylic Acid ◽

Anion Exchange ◽

Graft Polymerization ◽

The Other ◽

Practical Applications ◽

Bipolar Membranes ◽

Graft Polymers ◽

Grafting Reactions ◽

Radiation Induced

We prepared novel bipolar membranes (BPMs) consisting of cation and anion exchange layers (CEL and AEL) using radiation-induced asymmetric graft polymerization (RIAGP). In this technique, graft polymers containing cation and anion exchange groups were introduced into a base film from each side. To create a clear CEL/AEL boundary, grafting reactions were performed from each surface side using two graft monomer solutions, which are immiscible in each other. Sodium p-styrenesulfonate (SSS) and acrylic acid (AA) in water were co-grafted from one side of the base ethylene-co-tetrafluoroethylene film, and chloromethyl styrene (CMS) in xylene was simultaneously grafted from the other side, and then the CMS units were quaternized to afford a BPM. The distinct SSS + AA- and CMS-grafted layers were formed owing to the immiscibility of hydrophilic SSS + AA and hydrophobic CMS monomer solutions. This is the first BPM with a clear CEL/AEL boundary prepared by RIAGP. However, in this BPM, the CEL was considerably thinner than the AEL, which may be a problem in practical applications. Then, by using different starting times of the first SSS+AA and second CMS grafting reactions, the CEL and AEL thicknesses was found to be controlled in RIAGP.

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