The Effect of Mechanical Shot Blasting in Producing the Surface Ultrafined Grain Layer on Large-Size Titanium Plate

2018 ◽  
pp. 127-134
Author(s):  
Quantong Yao ◽  
Guanglan Zhang ◽  
Ying Gao ◽  
Weiping Tong
Keyword(s):  
Titanium Plate ◽  
Shot Blasting ◽  
Large Size

scholarly journals New Approach to Produce a Nanocrystalline Layer on Surface of a Large Size Pure Titanium Plate

Coatings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 430
Author(s):  
Yuzhu Fu ◽  
Ge Wang ◽  
Jing Gao ◽  
Quantong Yao ◽  
Weiping Tong
Keyword(s):  
Pure Titanium ◽  
Grain Morphology ◽  
Optical Microscope ◽  
Surface Mechanical Attrition Treatment ◽  
Titanium Plate ◽  
Hardness Tester ◽  
Large Size ◽  
Transmission Electron ◽  
Average Grain Size ◽  
Nanocrystalline Layer

It was demonstrated that the mechanical shot peening (MSP) technique was a viable way to obtain a nanocrystalline layer on a large size pure titanium plate due to the MSP provided for severe plastic deformation (SPD) of surface high velocity balls impacting. The MSP effects of various durations in producing the surface nanocrystalline layer was characterized by optical microscope (OM), X-ray diffraction (XRD), transmission electron microscope (TEM), and Vickers micro-hardness tester. The results showed that the thickness of the SPD layer gradually increased with the MSP processing time increase, but saturated at 230 μm after 30 min. The average grain size was refined to about 18.48 nm in the nanocrystalline layer. There was equiaxed grain morphology with random crystallographic orientation in the topmost surface. By comparing with the nanocrystalline layer, acquired by surface mechanical attrition treatment (SMAT), the microstructure and properties of the nanocrystalline layer acquired by MSP was evidently superior to that of the SMAT, but the production time was cut to about a quarter of the time used for the SMAT method.

Coherency loss in γ' precipitates in nickel-base superalloy

1983 ◽  
Vol 41 ◽  
pp. 244-245
Author(s):  
R. A. Ricks ◽  
Angus J. Porter
Keyword(s):  
Lattice Mismatch ◽  
Lattice Parameter ◽  
Nickel Base Superalloy ◽  
Large Size ◽  
The Matrix ◽  
Nimonic 80A ◽  
Interfacial Dislocations ◽  
Nickel Base ◽  
Coherency Loss ◽  
Nimonic 115

During a recent investigation concerning the growth of γ' precipitates in nickel-base superalloys it was observed that the sign of the lattice mismatch between the coherent particles and the matrix (γ) was important in determining the ease with which matrix dislocations could be incorporated into the interface to relieve coherency strains. Thus alloys with a negative misfit (ie. the γ' lattice parameter was smaller than the matrix) could lose coherency easily and γ/γ' interfaces would exhibit regularly spaced networks of dislocations, as shown in figure 1 for the case of Nimonic 115 (misfit = -0.15%). In contrast, γ' particles in alloys with a positive misfit could grow to a large size and not show any such dislocation arrangements in the interface, thus indicating that coherency had not been lost. Figure 2 depicts a large γ' precipitate in Nimonic 80A (misfit = +0.32%) showing few interfacial dislocations.

Automatic analysis of Kikuchi diffraction patterns

1994 ◽  
Vol 52 ◽  
pp. 900-901
Author(s):  
H. Weiland ◽  
D. P. Field
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Spatial Resolution ◽  
Relevant Information ◽  
Crystalline Materials ◽  
Large Size ◽  
Transmission Electron ◽  
New Type ◽  
Diffraction Patterns ◽  
Orientation Determination

Recent advances in the automatic indexing of backscatter Kikuchi diffraction patterns on the scanning electron microscope (SEM) has resulted in the development of a new type of microscopy. The ability to obtain statistically relevant information on the spatial distribution of crystallite orientations is giving rise to new insight into polycrystalline microstructures and their relation to materials properties. A limitation of the technique in the SEM is that the spatial resolution of the measurement is restricted by the relatively large size of the electron beam in relation to various microstructural features. Typically the spatial resolution in the SEM is limited to about half a micron or greater. Heavily worked structures exhibit microstructural features much finer than this and require resolution on the order of nanometers for accurate characterization. Transmission electron microscope (TEM) techniques offer sufficient resolution to investigate heavily worked crystalline materials.Crystal lattice orientation determination from Kikuchi diffraction patterns in the TEM (Figure 1) requires knowledge of the relative positions of at least three non-parallel Kikuchi line pairs in relation to the crystallite and the electron beam.

Immunoprobe localization in mammalian embryos

1990 ◽  
Vol 48 (3) ◽  
pp. 32-33
Author(s):  
Patricia G. Calarco ◽  
Margaret C. Siebert
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Thin Sections ◽  
Relative Lack ◽  
Large Size ◽  
Mammalian Embryos ◽  
Antigen Localization ◽  
Difficult Challenge ◽  
Lowicryl K4m ◽  
Fertilized Egg

Visualization of preimplantation mammalian embryos by electron microscopy is difficult due to the large size of the ircells, their relative lack of internal structure, and their highly hydrated cytoplasm. For example, the fertilized egg of the mouse is a single cell of approximately 75μ in diameter with little organized cytoskelet on and apaucity ofor ganelles such as endoplasmic reticulum (ER) and Golgi material. Thus, techniques that work well on tissues or cell lines are often not adaptable to embryos at either the LM or EM level.Over several years we have perfected techniques for visualization of mammalian embryos by LM and TEM, SEM and for the pre-embedding localization of antigens. Post-embedding antigenlocalization in thin sections of mouse oocytes and embryos has presented a more difficult challenge and has been explored in LR White, LR Gold, soft EPON (after etching of sections), and Lowicryl K4M. To date, antigen localization has only been achieved in Lowicryl-embedded material, although even with polymerization at-40°C, the small ER vesicles characteristic of embryos are unrecognizable.

Vibration Isolator System for Electron Microscope

1990 ◽  
Vol 48 (1) ◽  
pp. 182-183
Author(s):  
K. Ohi ◽  
M. Mizuno ◽  
T. Kasai ◽  
Y. Ohkura ◽  
K. Mizuno ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Magnetic Fields ◽  
Environmental Conditions ◽  
Vibration Isolator ◽  
Air Conditioners ◽  
Vibration Isolators ◽  
Large Size ◽  
Electron Microscopes

In recent years, with electron microscopes coming into wider use, their installation environments do not necessarily give their performance full play. Their environmental conditions include air-conditioners, magnetic fields, and vibrations. We report a jointly developed entirely new vibration isolator which is effective against the vibrations transmitted from the floor.Conventionally, large-sized vibration isolators which need the digging of a pit have been used. These vibration isolators, however, are large present problems of installation and maintenance because of their large-size.Thus, we intended to make a vibration isolator which1) eliminates the need for changing the installation room2) eliminates the need of maintenance and3) are compact in size and easily installable.

Clinically Meaningful Change

Methodology ◽  
2019 ◽  
Vol 15 (3) ◽  
pp. 97-105
Author(s):  
Rodrigo Ferrer ◽  
Antonio Pardo
Keyword(s):  
Effect Size ◽  
False Negative ◽  
False Negative Rate ◽  
Point Of View ◽  
Skewed Distribution ◽  
Effect Sizes ◽  
False Negatives ◽  
Large Size ◽  
Before And After ◽  
Post Test

Abstract. In a recent paper, Ferrer and Pardo (2014) tested several distribution-based methods designed to assess when test scores obtained before and after an intervention reflect a statistically reliable change. However, we still do not know how these methods perform from the point of view of false negatives. For this purpose, we have simulated change scenarios (different effect sizes in a pre-post-test design) with distributions of different shapes and with different sample sizes. For each simulated scenario, we generated 1,000 samples. In each sample, we recorded the false-negative rate of the five distribution-based methods with the best performance from the point of view of the false positives. Our results have revealed unacceptable rates of false negatives even with effects of very large size, starting from 31.8% in an optimistic scenario (effect size of 2.0 and a normal distribution) to 99.9% in the worst scenario (effect size of 0.2 and a highly skewed distribution). Therefore, our results suggest that the widely used distribution-based methods must be applied with caution in a clinical context, because they need huge effect sizes to detect a true change. However, we made some considerations regarding the effect size and the cut-off points commonly used which allow us to be more precise in our estimates.

Wire fixation versus rigid titanium plate after sternotomy – Results of a randomized, prospective, multi-center trial

2012 ◽  
Vol 60 (S 01) ◽  
Author(s):  
S Lehmann ◽  
MS Wong ◽  
K Zehr ◽  
BJ DeGuzman ◽  
HE Garrett ◽  
...  
Keyword(s):  
Titanium Plate ◽  
Wire Fixation

MANAGEMENT OF BLADDER STONE WITH HOLMIUM-YAG LASER AT KARDINAH HOSPITAL TEGAL

2020 ◽  
Vol 27 (1) ◽  
pp. 1-4
Author(s):  
Fatan Abshari ◽  
Zulfikar Ali
Keyword(s):  
General Hospital ◽  
Laser Energy ◽  
Major Complication ◽  
Mucosal Injury ◽  
Cross Sectional Study ◽  
Stone Size ◽  
Cross Sectional ◽  
Yag Laser ◽  
Bladder Stones ◽  
Large Size

Objective: Transurethral lithotripsy using Holmium-YAG laser has been reported to be beneficial in breaking up bladder stones with large size (>4cm in diameter) with lower risk of mucosal injury and hematuria. The aim of this study is to evaluate the utilization of Holmium-YAG laser for the management of bladder stones at Kardinah General Hospital, Tegal. Material & Methods: This is a cross-sectional study conducted from January 2017 to March 2017. Patient’s demography, which included age, sex, length of surgery, stone size, and laser’s energy count were recorded. Results: We included 120 patients in this study. Mean of patients age in this study was 51.93 years old with age range were 41-85 years old. Most of the patients were male (109 vs 11) with a mean size of stone 25.09 ± 3.04 mm. Length of surgery ranges from 15 to 75 minutes and mean energy of the laser 28.99 ± 19.34 kJ. There was 100% stone’s clearance following surgery with no major complication occurred. Conclusion: Holmium-YAG laser is effective in managing bladder stones at Kardinah General Hospital particularly for large size stones. Length of surgery and energy of laser used depend on the stone size in which bigger stone size is associated with longer surgery time and bigger laser energy needed.

Ion Channel Remodelling in Atrial Fibrillation

2011 ◽  
Vol 7 (2) ◽  
pp. 97 ◽  
Author(s):  
Niels Voigt ◽  
Dobromir Dobrev ◽  
◽  
Keyword(s):  
Atrial Fibrillation ◽  
Ion Channel ◽  
Antiarrhythmic Drugs ◽  
Current Knowledge ◽  
Bleeding Complications ◽  
Large Size ◽  
Cardiovascular Morbidity And Mortality ◽  
Number Of Patients ◽  
Life Threatening ◽  
Underlying Mechanisms

Atrial fibrillation (AF) is the most common arrhythmia and is associated with substantial cardiovascular morbidity and mortality, with stroke being the most critical complication. Present drugs used for the therapy of AF (antiarrhythmics and anticoagulants) have major limitations, including incomplete efficacy, risks of life-threatening proarrhythmic events and bleeding complications. Non-pharmacological ablation procedures are efficient and apparently safe, but the very large size of the patient population allows ablation treatment of only a small number of patients. These limitations largely result from limited knowledge about the underlying mechanisms of AF and there is a hope that a better understanding of the molecular basis of AF may lead to the discovery of safer and more effective therapeutic targets. This article reviews the current knowledge about AF-related ion-channel remodelling and discusses how these alterations might affect the efficacy of antiarrhythmic drugs.

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