Retained Austenite Benefits or Avoidance Requires Dependable Determination

Sediments commonly contain organic material which appears as refractory carbonaceous material in metamorphosed sedimentary rocks. Grew and others have shown that relative carbon content, crystallite size, X-ray crystallinity and development of well-ordered graphite crystal structure of the carbonaceous material increases with increasing metamorphic grade. The graphitization process is irreversible and appears to be continous from the amorphous to the completely graphitized stage. The most dramatic chemical and crystallographic changes take place within the chlorite metamorphic zone.The detailed X-ray investigation of crystallite size and crystalline ordering is complex and can best be investigated by other means such as high resolution transmission electron microscopy (HRTEM). The natural graphitization series is similar to that for heat-treated commercial carbon blacks, which have been successfully studied by HRTEM (Ban and others).

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Low temperature x-ray microanalysis of frozen-hydrated tobacco leaves

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111537 ◽

1984 ◽

Vol 42 ◽

pp. 284-285

Author(s):

S. Edith Taylor ◽

Patrick Echlin ◽

May McKoon ◽

Thomas L. Hayes

Keyword(s):

Low Temperature ◽

Lemna Minor ◽

Root Tips ◽

Tobacco Leaves ◽

X Ray ◽

Whole Cells ◽

Carbon Coated ◽

The Right ◽

Beam Currents ◽

The University

Low temperature x-ray microanalysis (LTXM) of solid biological materials has been documented for Lemna minor L. root tips. This discussion will be limited to a demonstration of LTXM for measuring relative elemental distributions of P,S,Cl and K species within whole cells of tobacco leaves.Mature Wisconsin-38 tobacco was grown in the greenhouse at the University of California, Berkeley and picked daily from the mid-stalk position (leaf #9). The tissue was excised from the right of the mid rib and rapidly frozen in liquid nitrogen slush. It was then placed into an Amray biochamber and maintained at 103K. Fracture faces of the tissue were prepared and carbon-coated in the biochamber. The prepared sample was transferred from the biochamber to the Amray 1000A SEM equipped with a cold stage to maintain low temperatures at 103K. Analyses were performed using a tungsten source with accelerating voltages of 17.5 to 20 KV and beam currents from 1-2nA.

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The effect of small additions of Cu on precipitation in Al-Mg-Si alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135812 ◽

1990 ◽

Vol 48 (2) ◽

pp. 442-443

Author(s):

M. Tamizifar ◽

G. Cliff ◽

R.W. Devenish ◽

G.W. Lorimer

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Scanning Transmission Electron Microscope ◽

Argon Atmosphere ◽

Age Hardening ◽

X Ray ◽

Transmission Electron ◽

Heat Treated ◽

Analytical Electron ◽

Scanning Transmission

Small additions of copper, <1 wt%, have a pronounced effect on the ageing response of Al-Mg-Si alloys. The object of the present investigation was to study the effect of additions of copper up to 0.5 wt% on the ageing response of a series of Al-Mg-Si alloys and to use high resolution analytical electron microscopy to determine the composition of the age hardening precipitates.The composition of the alloys investigated is given in Table 1. The alloys were heat treated in an argon atmosphere for 30m, water quenched and immediately aged either at 180°C for 15 h or given a duplex treatment of 180°C for 15 h followed by 350°C for 2 h2. The double-ageing treatment was similar to that carried out by Dumolt et al. Analyses of the precipitation were carried out with a HB 501 Scanning Transmission Electron Microscope. X-ray peak integrals were converted into weight fractions using the ratio technique of Cliff and Lorimer.

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Long-period modulated superstructures in Pd-12.5 at.%Ce and Pd-15 at.%Ce alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173959 ◽

1990 ◽

Vol 48 (4) ◽

pp. 164-165

Author(s):

Noriyuki Kuwano ◽

Masaru Itakura ◽

Kensuke Oki

Keyword(s):

Electron Microscopy ◽

Mean Value ◽

Heavy Elements ◽

Arc Furnace ◽

X Ray ◽

Long Period ◽

Ultra High Purity ◽

Heat Treated ◽

Atomic Scattering ◽

The Mean

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.

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Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

10.26434/chemrxiv.13146278.v1 ◽

2020 ◽

Author(s):

Pia Vervoorts ◽

Stefan Burger ◽

Karina Hemmer ◽

Gregor Kieslich

Keyword(s):

High Pressure ◽

State Of The Art ◽

Energy Landscape ◽

Structural Flexibility ◽

Zeolitic Imidazolate Frameworks ◽

Stimuli Responsive ◽

X Ray Diffraction ◽

X Ray ◽

Open Questions ◽

Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to p = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at p = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).

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Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

10.26434/chemrxiv.13146278 ◽

2020 ◽

Author(s):

Pia Vervoorts ◽

Stefan Burger ◽

Karina Hemmer ◽

Gregor Kieslich

Keyword(s):

High Pressure ◽

State Of The Art ◽

Energy Landscape ◽

Structural Flexibility ◽

Zeolitic Imidazolate Frameworks ◽

Stimuli Responsive ◽

X Ray Diffraction ◽

X Ray ◽

Open Questions ◽

Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to p = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at p = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).

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Infra-Red Reflectance Microscopy (IRRM) for Daisy Chain Flip Chip Device Failure Analysis

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0669 ◽

2004 ◽

Author(s):

Carlo Grilletto ◽

Steve Hsiung ◽

Andrew Komrowski ◽

John Soopikian ◽

Daniel J.D. Sullivan ◽

...

Keyword(s):

Failure Analysis ◽

Flip Chip ◽

State Of The Art ◽

Failure Mechanisms ◽

Simple Metal ◽

X Ray ◽

Infra Red ◽

Cause Of Failure ◽

Reflectance Microscopy ◽

Ir Emission

Abstract This paper describes a method to "non-destructively" inspect the bump side of an assembled flip-chip test die. The method is used in conjunction with a simple metal-connecting "modified daisy chain" die and makes use of the fact that polished silicon is transparent to infra-red (IR) light. The paper describes the technique, scope of detection and examples of failure mechanisms successfully identified. It includes an example of a shorting anomaly that was not detectable with the state of the art X-ray equipment, but was detected by an IR emission microscope. The anomalies, in many cases, have shown to be the cause of failure. Once this has been accomplished, then a reasonable deprocessing plan can be instituted to proceed with the failure analysis.

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CLINICAL CASE OF A MALIGNANT PECOMA OF THE LUNG

Problems in oncology ◽

10.37469/0507-3758-2019-65-5-756-759 ◽

2019 ◽

Vol 65 (5) ◽

pp. 756-759

Author(s):

Mikhail Postolov ◽

Nadezhda Kovalenko ◽

K. Babina ◽

Stanislav Panin ◽

Yelena Levchenko ◽

...

Keyword(s):

Good Condition ◽

Lung Neoplasm ◽

Rare Condition ◽

Epithelioid Cell ◽

X Ray ◽

Perivascular Epithelioid Cell ◽

Mesenchymal Neoplasm ◽

Preoperative Ct ◽

Lymph Duct ◽

The Right

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm characterized by expression of both mela-nocytic and smooth muscle markers. Only 10 primary malignant lung PEComas have been reported up to date. We report a 59-year-old male who presented with a lung neoplasm, found during the routine X-ray examination. Preoperative CT-scan revealed the 3,5-cm-sized mass, located at the border of the upper, middle and lower lobes of the right lung. Patient underwent a thoracotomy, resection of the upper, middle and lower lobes of the right lung accompanied with mediastinal lymphadenectomy. After surgery, chylothorax was revealed. Conservative treatment was unsuccessful, so we performed laparoscopic clipping of the thoracic lymph duct. Patient was dismissed from hospital on the 10-th day after the second operation in good condition. In this report, we intend to increase the limited knowledge relating to natural history and optimal treatment of such a rare condition as a primary malignant lung PEComa.

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COVID-19 infection map generation and detection from chest X-ray images

Health Information Science and Systems ◽

10.1007/s13755-021-00146-8 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Aysen Degerli ◽

Mete Ahishali ◽

Mehmet Yamac ◽

Serkan Kiranyaz ◽

Muhammad E. H. Chowdhury ◽

...

Keyword(s):

State Of The Art ◽

Ground Truth ◽

Clinical Use ◽

X Ray ◽

Learning Techniques ◽

Map Generation ◽

Severity Grading ◽

Chest X Ray ◽

Novel Method ◽

Aided Diagnosis

AbstractComputer-aided diagnosis has become a necessity for accurate and immediate coronavirus disease 2019 (COVID-19) detection to aid treatment and prevent the spread of the virus. Numerous studies have proposed to use Deep Learning techniques for COVID-19 diagnosis. However, they have used very limited chest X-ray (CXR) image repositories for evaluation with a small number, a few hundreds, of COVID-19 samples. Moreover, these methods can neither localize nor grade the severity of COVID-19 infection. For this purpose, recent studies proposed to explore the activation maps of deep networks. However, they remain inaccurate for localizing the actual infestation making them unreliable for clinical use. This study proposes a novel method for the joint localization, severity grading, and detection of COVID-19 from CXR images by generating the so-called infection maps. To accomplish this, we have compiled the largest dataset with 119,316 CXR images including 2951 COVID-19 samples, where the annotation of the ground-truth segmentation masks is performed on CXRs by a novel collaborative human–machine approach. Furthermore, we publicly release the first CXR dataset with the ground-truth segmentation masks of the COVID-19 infected regions. A detailed set of experiments show that state-of-the-art segmentation networks can learn to localize COVID-19 infection with an F1-score of 83.20%, which is significantly superior to the activation maps created by the previous methods. Finally, the proposed approach achieved a COVID-19 detection performance with 94.96% sensitivity and 99.88% specificity.

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