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Make blades very sharp
Published in Michael Wiklund, Kimmy Ansems, Rachel Aronchick, Cory Costantino, Alix Dorfman, Brenda van Geel, Jonathan Kendler, Valerie Ng, Ruben Post, Jon Tilliss, Designing for Safe Use, 2019
Michael Wiklund, Kimmy Ansems, Rachel Aronchick, Cory Costantino, Alix Dorfman, Brenda van Geel, Jonathan Kendler, Valerie Ng, Ruben Post, Jon Tilliss
It’s quite convenient when products incorporating blades can sharpen themselves or have holders that do the trick. One particular manufacturer offers knives that are stored in a knife block containing slots that are engineered to sharpen a knife with every withdrawal and reinsertion.3 One chainsaw has a built-in mechanism that simply requires the user to pull a lever to expose the moving chain to an internally mounted sharpener.4 Chain-sharpening attachments are also available to ease the task and help ensure the tool cuts safely and effectively.
Effects of 5.8 GHz microwave on hippocampal synaptic plasticity of rats
Published in International Journal of Environmental Health Research, 2022
Gang Rui, Li-Yuan Liu, Ling Guo, Yi-Zhe Xue, Pan-Pan Lai, Peng Gao, Jun-Ling Xing, Jing Li, Gui-Rong Ding
After flushing out the blood with 0.9% sodium chloride, the brains were harvested and the hippocampus was isolated. Small pieces of tissue specimens are optimally placed rapidly into glutaraldehyde and fixed for at least 1 h at room temperature and then post-fixed in osmium tetroxide. Fixed cells are embedded in agar. The specimens are dehydrated in graded concentrations of ethanol and propylene oxide, and embedded in Spurr’s plastic. Semi-thin sections are cut from blocks with a glass knife and the blocks are selected for thinning. Thin sections cut with diamond knives are placed on copper grids, impregnated with uranyl acetate and lead citrate, and scoped. The experiment was conducted using 4 independent animals from each group. The size of synapses, the number of synaptic vesicles, the width of synaptic cleft and the area of postsynaptic dense was detected and measured by Fiji (NIH, USA).
Adapting L-PBF process for fine powders: a case study in 420 stainless steel
Published in Materials and Manufacturing Processes, 2022
Subrata Deb Nath, Alfred Okello, Rajendra Kelkar, Gautam Gupta, Martin Kearns, Sundar V. Atre
Herein, L-PBF of AISI 420 stainless steel that offers high hardness, strength and corrosion resistance was investigated. The applications of 420 stainless steel include surgical instruments, knives, bearings, and tooling. AISI 420 stainless steel is primarily a Fe-Cr-C ternary system which typically contains 12 ~ 14% Cr and > 0.15% C, with minor additions of several other alloying elements. The crystal structure of 420 stainless steel may consist of martensite, retained austenite and ferrite phases and dissolved or undissolved carbides.[16] Depending on the carbon content and heat treatment, the strength of this martensitic stainless steel can reach to 1800 MPa and elongation to 8%.[17] In addition, presence of >12% of chromium in the chemical composition provides this medium carbon steel good corrosion resistance as a layer of Cr2O3 helps to avoid corrosion through passivation.[16]
Comparison of Analysis Results on Three Methods for Sampling Crud, a Radioactive Corrosion Product with Zinc-Injected Spent PWR Nuclear Fuel Rods
Published in Nuclear Technology, 2021
Yang Hong Jung, Seung Je Baik, Young Gwan Jin
Figure 6 shows SEM and X-ray mapping images of samples taken by the ultrasonic cleaner. From the quantitative analysis table in Fig. 6d, it can be confirmed that a large amount of zirconium exists. This is an element often found in samples taken from steel knives in hot cells. Zirconium found in samples with a steel knife scraped from the surface of the cladding may be enough to damage the cladding. However, the zirconium in the quantitative analysis table in Fig. 6d must originate from the cladding oxide layer. This is because waves used in ultrasonic cleaners cannot damage the cladding. Also, the ratio of Ni/Fe was 1.36 as shown in Table I. As shown in Table I, the soft crud had a Ni/Fe ratio of about 1:1. On the other hand, the ratio of hard crud and the ultrasonic cleaner crud was 1.4. It is recognized that the overall crud sample shape is uneven like a pile of stones, and the reliability of the quantitative analysis value is low. However, based on the results shown in Table I analyzed by four methods, the ration of Ni/Fe added together and expressed as an average becomes about 1.18.