Rosat and Optical Observations of Supersoft X-Ray Sources

AbstractWe present X-ray and optical observations of the ROSAT discovered polar (AM Her binary) RX J1015.5+0904 and first results of our analysis of the X-ray and optical data. These results indicate a one-pole accretion geometry and an orbital period of P = 79.88 m for this V ~ 17 mag system.

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A simple hermetic sample holder for X-ray diffraction analysis of uranium hydride

Journal of Applied Crystallography ◽

10.1107/s0021889807024661 ◽

2007 ◽

Vol 40 (4) ◽

pp. 796-798 ◽

Cited By ~ 4

Author(s):

Bingyun Ao ◽

Xiaolin Wang ◽

Yongjun Wei ◽

Yanzhi Zhang

Keyword(s):

Diffraction Analysis ◽

Sample Holder ◽

X Ray Diffraction ◽

Aging Effects ◽

X Ray ◽

Long Term Storage ◽

Toxic Materials ◽

First Results ◽

Term Storage

In order to help resolve unknowns regarding aging effects of uranium during long-term storage of tritium, a number of experiments have been carried out by several researchers. However, almost no literature is available on the structural change of uranium tritide, mainly because its high toxicity and air-sensitivity render appropriate experiments very difficult. In this paper, a simple hermetic sample holder that fits the Philips X'Pert Pro X-ray diffractometer is described. It may be used to study the aging effects of uranium tritide during storage. The sample holder mainly consists of an aluminium container for sample storage and a Mylar window for X-ray measurements. This sample holder can also be used with other air-sensitive, radioactive and toxic materials. In this paper, the first results obtained from X-ray diffraction analysis of uranium hydride are presented.

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Multicolour photometry of SS 433

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318008529 ◽

2018 ◽

Vol 14 (S346) ◽

pp. 252-254

Author(s):

D. Koçak ◽

T. İçli ◽

K. Yakut

Keyword(s):

Black Hole ◽

Binary System ◽

Optical Observations ◽

High Mass ◽

National Observatory ◽

X Ray ◽

Ss 433

AbstractWe presented long-term optical observations of the high mass X-ray binary system SS 433 (V1343 Aql) with a black hole component. New observations have been obtained by using the 0.6m telescope at the TÜBİTAK National Observatory (TUG) in B, V, R and I filters. We aim to investigate the long-term photometric behavior of the system.

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Properties of individual X-ray sources: (Invited discourse)

Symposium - International Astronomical Union ◽

10.1017/s0074180900004034 ◽

1970 ◽

Vol 37 ◽

pp. 59-80

Author(s):

Laurence E. Peterson

Keyword(s):

Power Law ◽

Crab Nebula ◽

Optical Observations ◽

X Rays ◽

X Ray ◽

Upper Limits ◽

Time Variations ◽

Γ Rays ◽

The Crab Nebula

Observations to determine the spectra and time variations of hard X-rays from cosmic sources have been made from balloons and from the OSO-III satellite. These data have been obtained using actively collimated scintillation counters with apertures between 6 and 24° FWHM, areas between 10 and 50 cm2 and which operate over the 10–300 keV range. The Crab Nebula has been observed on three occasions over a 22-month period between September 1965 and July 1967. The power law spectrum has a number index of 2.0 ± 0.1. No long-term changes were observed over the 30–100 keV range with a limit at 3%/yr. A balloon search with a 10 cm2 Ge(Li) detector for X-ray lines at 62.5 keV, 110 keV and 180 keV due to heavy element radioactive decays which would be produced in the initial Crab explosion based on the Cf254 hypothesis has resulted in upper limits at about 10−3 γ-rays cm2-sec. This is about a factor of 20 above the predicted levels. Simultaneous X-ray and optical observations of SCO XR-1 from OSO-III confirm that X-ray and optical flaring are indeed coincident phenomena, and that although the X-ray intensity increases about a factor of two during the flare, the equivalent temperature of the excess radiation is nearly the same as that of the quiescent object. Upper limits, 95% confidence, on the flux of M-87 at 40 keV have been obtained. These are inconsistent with the flux of 1.2 × 10−4 photons/cm2-sec-keV reported in the literature. CYG X-1 has been observed to have a power law of number index 2.0 ± 0.2. The OSO-III has observed a number of sources in the southern skies including NOR XR-2 and the variable source Centaurus XR-2.

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LONG-TERM OPTICAL OBSERVATIONS OF THE Be/X-RAY BINARY X PER

The Astronomical Journal ◽

10.1088/0004-6256/148/6/113 ◽

2014 ◽

Vol 148 (6) ◽

pp. 113 ◽

Cited By ~ 5

Author(s):

Hui Li ◽

Jingzhi Yan ◽

Jianeng Zhou ◽

Qingzhong Liu

Keyword(s):

Optical Observations ◽

X Ray

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Preparation And elemental analysis of ancient fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126846 ◽

1987 ◽

Vol 45 ◽

pp. 410-411

Author(s):

Allen Angel ◽

Kathryn A. Jakes

Keyword(s):

Cross Sections ◽

Physical Structure ◽

Energy Dispersive ◽

Archaeological Sites ◽

X Ray ◽

Long Term Storage ◽

Backscattered Electron ◽

Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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Long-term variations in individual particle types in the aerosol of Phoenix, Arizona, as determined using automated electron microprobe analysis and multivariate statistical techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149544 ◽

1993 ◽

Vol 51 ◽

pp. 742-743

Author(s):

Karen A. Katrinak ◽

James R. Anderson ◽

Peter R. Buseck

Keyword(s):

Electron Microprobe ◽

Fine Fraction ◽

Coarse Fraction ◽

Motor Vehicles ◽

Multivariate Statistical Methods ◽

Multivariate Statistical ◽

X Ray ◽

Mineral Particles ◽

Anthropogenic Air Pollutants

Aerosol samples were collected in Phoenix, Arizona on eleven dates between July 1989 and April 1990. Elemental compositions were determined for approximately 1000 particles per sample using an electron microprobe with an energy-dispersive x-ray spectrometer. Fine-fraction samples (particle cut size of 1 to 2 μm) were analyzed for each date; coarse-fraction samples were also analyzed for four of the dates.The data were reduced using multivariate statistical methods. Cluster analysis was first used to define 35 particle types. 81% of all fine-fraction particles and 84% of the coarse-fraction particles were assigned to these types, which include mineral, metal-rich, sulfur-rich, and salt categories. "Zero-count" particles, consisting entirely of elements lighter than Na, constitute an additional category and dominate the fine fraction, reflecting the importance of anthropogenic air pollutants such as those emitted by motor vehicles. Si- and Ca-rich mineral particles dominate the coarse fraction and are also numerous in the fine fraction.

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Stents for the Treatment of Aortic Aneurysms

Thrombosis and Haemostasis ◽

10.1055/s-0037-1615578 ◽

1999 ◽

Vol 82 (S 01) ◽

pp. 171-175 ◽

Cited By ~ 1

Author(s):

D. Ebert ◽

M. Langer ◽

P. Uhrmeister

Keyword(s):

Endovascular Treatment ◽

Endovascular Repair ◽

Abdominal Aortic Aneurysms ◽

Aortic Aneurysms ◽

Imaging Modalities ◽

Exclusion Criteria ◽

Multicenter Studies ◽

Abdominal Aortic ◽

First Results

SummaryThe endovascular treatment of abdominal aortic aneurysms has generated a great deal of interest since the early 1990s, and many different devices are currently available. The procedure of endovascular repair has been evaluated in many institutions and the different devices are compared. The first results were encouraging, but complications like endoleak, dislocation or thrombosis of the graft occurred. By the available devices the stent application is only promising, if the known exclusion criteria are strictly respected. Therefore a careful preinterventional assessment of the patient by different imaging modalities is necessary. As the available results up to now are preliminary and the durability of the devices has to be controlled, multicenter studies are required to improve the devices and observe their long- term success in the exclusion of abdominal aortic aneurysms.

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Study of Natural Minerals of U-Ryrochlore-Type Structure as Analogues of Plutonium Ceramic Waste-form

MRS Proceedings ◽

10.1557/proc-713-jj2.2 ◽

2002 ◽

Vol 713 ◽

Cited By ~ 1

Author(s):

Roman V. Bogdanov ◽

Yuri F. Batrakov ◽

Elena V. Puchkova ◽

Andrey S. Sergeev ◽

Boris E. Burakov

Keyword(s):

Chemical Shifts ◽

Pyrochlore Structure ◽

Type Structure ◽

Waste Form ◽

X Ray ◽

Ceramic Waste ◽

Natural Minerals ◽

The Us ◽

Pyrochlore Type

ABSTRACTAt present, crystalline ceramic based on titanate pyrochlore, (Ca,Gd,Hf,Pu,U)2Ti2O7, is considered as the US candidate waste form for the immobilization of weapons grade plutonium. Naturally occuring U-bearing minerals with pyrochlore-type structure: hatchettolite, betafite, and ellsworthite, were studied in orders to understand long-term radiation damage effects in Pu ceramic waste forms. Chemical shifts (δ) of U(Lδ1)– and U(Lβ1) – X-ray emission lines were measured by X-ray spectrometry. Calculations were performed on the basis of a two-dimensional δLá1- and δLδ1- correlation diagram. It was shown that 100% of uranium in hatchettolite and, probably, 95-100% of uranium in betafite are in the form of (UO2)2+. formal calculation shows that in ellsworthite only 20% of uranium is in the form of U4+ and 80% of the rest is in the forms of U5+ and U6+. The conversion of the initial U4+ ion originally occurring in the pyrochlore structure of natural minerals to (UO2)2+ due to metamict decay causes a significant increase in uranium mobility.

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Analysis of crystallite size changes in a hematite and magnetite formed on steel used in the power idustry

Technical Sciences ◽

10.31648/ts.2717 ◽

2017 ◽

Vol 1 (21) ◽

pp. 65-73

Author(s):

Monika Gwoździk

Keyword(s):

Elevated Temperature ◽

Oxide Layer ◽

Cross Section ◽

X Ray ◽

Term Operation ◽

Diffraction Line Profile ◽

Crystallite Sizes ◽

Scherrer Formula ◽

Pipe Outlet

The paper presents results of studies on the crystallite sizes of oxide layer formed during a long-term operation on 10CrMo9-10 steel at an elevated temperature (T = 545° C, t = 200,000 h). This value was determined by a method based on analysis of the diffraction line profile, according to a Scherrer formula. The oxide layer was studied on a surface and a cross-section at the outer and inner site on the pipe outlet, at the fire and counter-fire wall of the tube. X-ray studies were carried out on the surface of a tube, then the layer’s surface was polished and the diffraction measurements repeated to reveal differences in the originated oxides layer.

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