Group 14 semiconductor alloys in the P41212 phase: A comprehensive study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

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Hexachlorobenzene toxicity in the monkey ovary: III. Ultrastructure induced by high (10 mg/kg) dose exposure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084958 ◽

1991 ◽

Vol 49 ◽

pp. 130-131

Author(s):

A. Singh ◽

A. Dykeman ◽

J. Jarrelf ◽

D. C. Villeneuve

Keyword(s):

Present Report ◽

Reproductive Toxicity ◽

Control Group ◽

Primate Model ◽

Human Follicular Fluid ◽

Thin Sections ◽

Cynomolgus Monkeys ◽

Cacodylate Buffer ◽

Induction Cycle ◽

Comprehensive Study

Hexachlorobenzene (HCB), a persistent and mobile organochlorine pesticide, occurs in environment. HCB has been shown to be present in human follicular fluid. An objective of the present report, which is part of a comprehensive study on reproductive toxicity of HCB, was to determine the cytologic effects of the compound on ovarian follicles in a primate model.Materials and Methods. Eight Cynomolgus monkeys were housed under controlled conditions at Animal facility of Health and Welfare, Ottawa. Animals were orally administered gelatin capsules containing HCB mixed with glucose in daily dosages of 0.0 or 10 mg/kg b.w. for 90 days; the former was the control group. On the menstrual period following completion of dosing, the monkeys underwent an induction cycle of superovulation. At necropsy, one-half of an ovary from each animal was diced into ca. 2- to 3-mm cubed specimens that were fixed by immersion in 2.5% glutaraldehyde in 0.1 M cacodylate buffer (pH 7.3). Subsequent procedures followed to obtain thin sections that were examined in a Hitachi H-7000 electron microscope have been described earlier.

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Comparison of Substructures Between Uniaxial and Biaxial Deformation in 1100-0 Aluminum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096989 ◽

1981 ◽

Vol 39 ◽

pp. 52-53

Author(s):

D. L. Rohr ◽

S. S. Hecker

Keyword(s):

Plastic Strain ◽

Cell Walls ◽

Room Temperature ◽

Mechanical Response ◽

Biaxial Tension ◽

Initial Deformation ◽

Uniaxial Deformation ◽

Biaxial Deformation ◽

Stress States ◽

Comprehensive Study

As part of a comprehensive study of microstructural and mechanical response of metals to uniaxial and biaxial deformations, the development of substructure in 1100 A1 has been studied over a range of plastic strain for two stress states.Specimens of 1100 aluminum annealed at 350 C were tested in uniaxial (UT) and balanced biaxial tension (BBT) at room temperature to different strain levels. The biaxial specimens were produced by the in-plane punch stretching technique. Areas of known strain levels were prepared for TEM by lapping followed by jet electropolishing. All specimens were examined in a JEOL 200B run at 150 and 200 kV within 24 to 36 hours after testing.The development of the substructure with deformation is shown in Fig. 1 for both stress states. Initial deformation produces dislocation tangles, which form cell walls by 10% uniaxial deformation, and start to recover to form subgrains by 25%. The results of several hundred measurements of cell/subgrain sizes by a linear intercept technique are presented in Table I.

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A Tem Study of Slip Systems in MoSi2/WSi2 Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089020 ◽

1991 ◽

Vol 49 ◽

pp. 942-943

Author(s):

Stuart A. Maloy

Keyword(s):

Solid Solution ◽

Solid Solution Hardening ◽

Slip Systems ◽

High Melting ◽

Group 14 ◽

Solution Hardening ◽

Brittle To Ductile Transition ◽

High Melting Temperature ◽

Tetragonal Unit Cell ◽

Structural Applications

MoSi2 has recently been investigated as a potential material for high temperature structural applications. It has excellent oxidation resistance up to 1700°C, a high melting temperature, 2030°C, and a brittle-to-ductile transition temperature at 900-1000°C. WSi2 is isomorphous with MoSi2 and has a body-centered tetragonal unit cell of the space group 14/mmm. The lattice parameters are a=3.20 Å and c=7.84 Å for MoSi2 and a=3.21 Å and c=7.88 Å for WSi2. Therefore, WSi2 was added to MoSi2 to improve its strength via solid solution hardening. The purpose of this study was to investigate the slip systems in polycrystalline MoSi2/WSi2 alloys.

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Microvasculature and structure of hemal lymph nodes in the wall of the rabbit bladder: a vascular corrosion casting and EM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141743 ◽

1995 ◽

Vol 53 ◽

pp. 1074-1075

Author(s):

F.E. Hossler ◽

M.I. McKamey ◽

F.C. Monson

Keyword(s):

Lymph Nodes ◽

Light Microscopy ◽

Corrosion Casting ◽

Fixed Tissue ◽

Infusion Pressure ◽

India Ink ◽

Cacodylate Buffer ◽

Rabbit Bladder ◽

Lateral Walls ◽

Comprehensive Study

A comprehensive study of the microvasculature of the normal rabbit bladder, revealed unusual "capillary glomeruli" along the lateral walls. Here they are characterized as hemal lymph nodes using light microscopy, SEM, TEM, ink injection, and vascular casting.Bladders were perfused via a cannula placed in the abdominal aorta with either 2% glutaraldehyde in 0.1M cacodylate buffer (pH 7.4) for fixation, 10% India ink in 0.9% saline and 0.1M phosphate (pH 7.4) for vessel tracing, or resin (Mercoximethylmethacrylate: catalyst, 4:1:0.3; Ladd Research Industries) for vascular corrosion casting. Infusion pressure was 100mm Hg. Fixed tissue was sectioned from epon-araldyte resin, and stained with toluidine blue for light microscopy, and lead and uranium for TEM. Ink injected tissue was photographed directly from saline-filled bladders illuminated from below. Resin-filled tissue was macerated in 5% KOH and distilled water. Casts were critical point dried, sputter coated with goldpalladium, and examined by routine SEM at 10 KV.

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Comprehensive Study of Blockchain Technology - Architecture, Consensus and Future Trends

International Journal of Scientific Research in Computer Science Engineering and Information Technology ◽

10.32628/cseit206292 ◽

2020 ◽

pp. 319-325

Author(s):

Shreya Joshi ◽

Ms Bhavyaa ◽

Suhani Gupta ◽

Lalita Luthra

Keyword(s):

Internet Of Things ◽

Product Management ◽

Future Trends ◽

Deep Dive ◽

Record Keeping ◽

Blockchain Technology ◽

Healthcare Product ◽

Core Technology ◽

Technical Challenges ◽

Comprehensive Study

Blockchain is considered to be a disruptive core technology. Although many researchers have realized the importance of blockchain, but the research of it is still emerging. It is the record-keeping technology behind bitcoin and is one of the hottest and fastest growing skills in the IT sector today. It serves as an immutable ledger which allows transactions to take place in a decentralized man Blockchain-based applications are rising up, covering numerous fields including finance, healthcare, product management, Internet of Things (IoT), and many more. However, there are still some challenges of blockchain technology such as scalability and security problems which need to be overcome. This paper comprises of a comprehensive study of Blockchain technology. We have included here a deep dive into how blockchains work, its architecture, consensus and various applications. Furthermore, technical challenges are briefly listed.

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Hearing Outcome of Stapes Surgery in NIENT, Bangladesh

Bangladesh Journal of Otorhinolaryngology ◽

10.3329/bjo.v26i1.47950 ◽

2020 ◽

Vol 26 (1) ◽

pp. 31-36

Author(s):

Md Zakaria Sarkar ◽

AHM Ferdows Nur ◽

Utpal Kumar Dutta ◽

Muhammad Rafiqul Islam ◽

Debabrota Roy ◽

...

Keyword(s):

Hearing Loss ◽

Cross Sectional Study ◽

Surgical Trauma ◽

Group 14 ◽

Progressive Hearing Loss ◽

Cross Sectional ◽

Hearing Gain ◽

Hearing Outcome

Objective: The aim of this study was to evaluate hearing outcome after stapedotomy in patients with Otosclerosis. Methods: This cross sectional study was carried out from July 2017 to January 2019 in National Institute of ENT, Unit V. About 22 patients with Otosclerosis were included in this study. Diagnosis of Otosclerosis was based on the history, medical status with Otoscopy, Tuning fork tests and Audiometric tests. We compiled data on the pre and post operative air-bone gap (ABG) at 0.5, 1, 2 KHZ. The ABG was Calculated using AC and BC thresholds on the same audiogram. Post operative hearing gain was then Calculated from the ABG before the operation minus the ABG of the last follow up examination Results: In this study most of the cases were age group 14-30 years (72.7%), female (54.5%). Most common symptoms was progressive hearing loss, tinnitus (77.8%).The average preoperative hearing loss in this study was (AC) was 48.31±7.68. The average post opt. hearing (AC) at follow up was 28.95±10.30 with an average hearing gain of 15.40±8.53 dB which was significant. The average pre-operative ABG was 28.99 dB ± 8.10. The average post opt. ABG was analyzed at 1 follow up showed ABG 13.18±8.09 dB which was found to be significant. Conclusion: Stapedotomy is an effective surgical procedure for the treatment of otosclerosis which leads to improvement in patient’s quality of life. A favorable hearing outcome can be obtained by the combination of experienced hands with minimal surgical trauma and appropriate surgical technique. Bangladesh J Otorhinolaryngol; April 2020; 26(1): 31-36

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The Influence Of The Led Luminaires Electrical Parameters On Their Correlated Colour Temperature During Operation Mode

Light & Engineering ◽

10.33383/2020-025 ◽

2020 ◽

pp. 89-96

Author(s):

Sergei S. Kapitonov ◽

Alexei S. Vinokurov ◽

Sergei V. Prytkov ◽

Sergei Yu. Grigorovich ◽

Anastasia V. Kapitonova ◽

...

Keyword(s):

Operation Mode ◽

Light Sources ◽

Electrical Parameters ◽

Colour Temperature ◽

Radiation Spectra ◽

Service Period ◽

Close Proximity ◽

Definition Of ◽

Comprehensive Study

The article describes the results of comprehensive study aiming at increase of quality of LED luminaires and definition of the nature of changes in their correlated colour temperature (CCT) in the course of operation. Dependences of CCT of LED luminaires with remote and close location of phosphor for 10 thousand hours of operation in different electric modes were obtained; the results of comparison between the initial and final radiation spectra of the luminaires are presented; using mathematical statistics methods, variation of luminaire CCT over the service period claimed by the manufacturer is forecast; the least favourable electric operation modes with the highest CCT variation observed are defined. The obtained results have confirmed availability of the problem of variation of CCT of LED luminaires during their operation. Possible way of its resolution is application of more qualitative and therefore expensive LEDs with close proximity of phosphor or LEDs with remote phosphor. The article may be interesting both for manufacturers and consumers of LED light sources and lighting devices using them.

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