scholarly journals Vibration welding of high density polyehylene HDPE - purpose, application, weldingtechnology and quality of joints

2021 ◽  
Vol 51 (01) ◽  
pp. 63-70
Author(s):  
A. KISZKA ◽  
M. LOMOZIK
Keyword(s):  
High Density ◽  
Vibration Welding

The basis of quality of sheep pelts and fur products is morphological features of the skin of sheep

2020 ◽  
pp. 50-57
Author(s):  
I. Dmitrik ◽  
G. Zavgorodnyaya
Keyword(s):  
Mechanical Strength ◽  
Breaking Load ◽  
Hair Follicles ◽  
Morphological Features ◽  
High Density ◽  
Fat Cells ◽  
High Quality ◽  
Histological Features ◽  
Weakened Zone

The morphological and histological features of the skin and wool cover of sheep as the basis for the quality of fur sheep pelts have been studied. The most important properties of sheep pelts (uniformity, thinness and density of wool) are provide the possibility of producing high-quality fur semi-finished products from them. However, the features of the histostructure of fine-wool sheep determine the low mechanical strength of the “facial” layer of skin. As a result, the “front” layer during processing often cracks to the upper border of the reticular layer or even peels off from the latter, making the sheep pelt unsuitable for use on fur products. These defects in fur practice are called “cracking” and “peeling” of the facial layer. They are mainly peculiar to sheep pelts of fine-wooled sheep. In these animals due to the high density and tone of the coat, the roots and hair follicles, root vaginas, secretory departments, excretory ducts of the glands and other structures occupy a significant share of the volume in the thickness of the Pilar layer (up to 25–30 %). The share of fibrous structures remains less volume, and these structures themselves are relatively weakly developed, located loosely and loosely intertwined with each other. The accumulations of fat cells that occur here also cannot be attributed to skin-strengthening elements. In fine-fleece sheep the pilar layer is on average 60 % of the thickness of the dermis. Therefore, more than half of its thickness is a weakened zone. The strength of the “front” layer is not the same in different fine-wool breeds of sheep and in different animals within the breed. For example, the average breaking load for cod of the “front” layer in Soviet Merino pelts is 1,25 kg, and in Precoce is 2,49 kg.

scholarly journals Prolonged Storage of Lemons Using Individual Seal-packaging

1990 ◽  
Vol 115 (2) ◽  
pp. 251-255 ◽  
Author(s):  
E. Cohen ◽  
S. Lurie ◽  
B. Shapiro ◽  
S. Ben-Yehoshua ◽  
Y. Shalom ◽  
...  
Keyword(s):  
Water Potential ◽  
Water Relations ◽  
High Density Polyethylene ◽  
Storage Period ◽  
High Density ◽  
Prolonged Storage ◽  
Citrus Limon ◽  
Plastic Film ◽  
Maturity Indices

`Eureka' lemons [Citrus limon (L.) Burro. f.] treated for commercial storage were held for 6 months at 13C. One-half of the fruits were individually sealed in high-density polyethylene (HDPE) plastic film and half not sealed. The HDPE-seaIed lemons showed little change in the water relations characteristics, while unsealed lemons lost weight and decreased in water potential throughout the storage period. The maturity indices in the two treatments were generally similar during the first 3 months of storage, after which maturation of wrapped fruit was slower than that of the control. The overall marketable quality of the fruit was higher in HDPE-sealed lemons than in unsealed. From these results, it appears feasible to introduce seal packaging in packing lines where lemons will be placed in extended storage.

scholarly journals Aerospace Titanium Alloy Melt Process Quality Improvements

2020 ◽  
Vol 321 ◽  
pp. 04008
Author(s):  
Andrew Woodfield ◽  
Gérard Lemaitre
Keyword(s):  
Titanium Alloy ◽  
Aircraft Engine ◽  
Federal Aviation Administration ◽  
High Density ◽  
Vacuum Arc ◽  
Quality Improvements ◽  
Jet Engine ◽  
Aircraft Accident ◽  
The U.S

This Jet Engine Titanium Quality Committee (JETQC) paper describes industry quality improvements since 1990. Quality refers to freedom from melt-related hard-alpha and high-density inclusions (HDI). JETQC, formed under the auspices of the U.S. Federal Aviation Administration (FAA) following the Sioux City aircraft accident in 1989, is comprised of U.S., E.U. and Japanese aircraft engine manufacturers to address the quality of premium / rotor quality titanium alloy production. Titanium suppliers provide melt-related inclusion data. JETQC focuses on hard-alpha and HDI inclusion rates in premium quality (PQ) titanium alloy products for critical rotating aircraft engine applications. PQ materials typically are produced via triple vacuum arc re-melt (3XVAR) or hearth melt VAR (HMVAR) processes, but more recently, the Skull plus VAR (SVAR) process has been introduced. Hard-alpha rates have continued to decline over the last decade primarily for the HMVAR process. HDI rates declined in the early 90’s, but more recently the overall rate has stayed approximately constant with inclusions confined to the 3XVAR process. Combining the trends for both hard-alpha and HDIs, the HMVAR process has demonstrated in recent years to be higher quality compared with the 3XVAR process.

Quality of In‐House Made High‐Density Microarrays

2004 ◽  
pp. 1108-1112
Author(s):  
Paul van den IJssel ◽  
Paul Eijk ◽  
Erik Hopmans ◽  
Soemini Kasanmoentalib ◽  
Bauke Ylstra
Keyword(s):  
High Density

Application of Nondestructive Testing in Quality Controlling of High-Density Polyethylene Silicore Plastic Duct

2013 ◽  
Vol 470 ◽  
pp. 693-696
Author(s):  
Bai Yan Gong ◽  
Yu Hong Lu ◽  
Juan Ren
Keyword(s):  
Nondestructive Testing ◽  
Product Quality ◽  
High Density Polyethylene ◽  
High Density ◽  
Important Indicator ◽  
Breaking Elongation ◽  
Sampling Inspection ◽  
Weight Impact ◽  
Falling Weight

Some key quality problems has been exposed in several years of quality supervision sampling inspection of industry products for HDPE silicore plastic duct, such as dimension, breaking elongation, performance of falling weight impact and ring stiffness. Quality consistency is an important indicator in evaluating product quality. Nondestructive testing can be used to evaluate the quality of the whole pan and batch of silicore plastic duct, and it will play important role in product quality controlling.

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