scholarly journals The impact of temperature and unwanted impurities on slow compression of ice

2021 ◽  
Author(s):  
Christina Maria Tonauer ◽  
Marion Bauer ◽  
Thomas Loerting
Keyword(s):  
Polymorphic Transformation ◽  
High Density ◽  
Amorphous Ice ◽  
Hexagonal Ice ◽  
Ice Pressure ◽  
The Impact

For slowly compressed hexagonal ice pressure-induced amorphisation to high-density amorphous ice (HDA) takes place below and at 130 K, but polymorphic transformation to ice IX at 140–170 K. Stable ice...

Pure ices IV and XII from high-density amorphous ice

2003 ◽  
Vol 81 (1-2) ◽  
pp. 25-32 ◽  
Author(s):  
C G Salzmann ◽  
I Kohl ◽  
T Loerting ◽  
E Mayer ◽  
A Hallbrucker
Keyword(s):  
Constant Pressure ◽  
High Density ◽  
Slow Heating ◽  
Parallel Reaction ◽  
X Ray Diffraction ◽  
Fast Heating ◽  
X Ray ◽  
Amorphous Ice ◽  
Hexagonal Ice ◽  
Rate Conversion

High-density amorphous ice (HDA), made by compression of hexagonal ice at 77 K, was heated at a constant pressure of 0.81 GPa up to 183 K and its phase transition followed by displacement-temperature curves. The crystalline phases, recovered at 77 K and 1 bar, were characterized by X-ray diffraction. Pure D2O ice IV and nearly pure H2O ice IV were formed on slow heating at a rate of 0.4 K min–1, whereas pure H2O ice XII and D2O ice XII were formed on fast heating at [Formula: see text] 15 K min–1. On heating HDA at rates in between these two values a mixture of ice IV and ice XII was obtained, where their relative yields depended in a systematic manner on the heating rate. Conversion of HDA into either ice IV or ice XII is an example of a "parallel reaction" where the relative yields of ice IV and ice XII can be controlled by temperature, i.e., by the rate of heating, in our approach. It is conceivable that a similar behaviour occurs on crystallization of the related pressure-amorphized silica. PACS Nos.: 61.10-i, 64.60-i, 64.70-p

Evaluation of the Aging Behavior of High Density Polyethylene in Thermal Oxidative Environment by Principal Component Analysis

2017 ◽  
Vol 727 ◽  
pp. 447-449 ◽  
Author(s):  
Jun Dai ◽  
Hua Yan ◽  
Jian Jian Yang ◽  
Jun Jun Guo
Keyword(s):  
Principal Component Analysis ◽  
Impact Strength ◽  
High Density Polyethylene ◽  
Tensile Modulus ◽  
Principal Component ◽  
Component Analysis ◽  
High Density ◽  
Aging Behavior ◽  
Data Set ◽  
The Impact

To evaluate the aging behavior of high density polyethylene (HDPE) under an artificial accelerated environment, principal component analysis (PCA) was used to establish a non-dimensional expression Z from a data set of multiple degradation parameters of HDPE. In this study, HDPE samples were exposed to the accelerated thermal oxidative environment for different time intervals up to 64 days. The results showed that the combined evaluating parameter Z was characterized by three-stage changes. The combined evaluating parameter Z increased quickly in the first 16 days of exposure and then leveled off. After 40 days, it began to increase again. Among the 10 degradation parameters, branching degree, carbonyl index and hydroxyl index are strongly associated. The tensile modulus is highly correlated with the impact strength. The tensile strength, tensile modulus and impact strength are negatively correlated with the crystallinity.

scholarly journals High-Density Lipoproteins and the Kidney

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 764
Author(s):  
Arianna Strazzella ◽  
Alice Ossoli ◽  
Laura Calabresi
Keyword(s):  
Kidney Disease ◽  
Renal Disease ◽  
Cholesterol Acyltransferase ◽  
Density Lipoprotein ◽  
Hdl Cholesterol ◽  
High Density ◽  
High Density Lipoproteins ◽  
Lcat Deficiency ◽  
Progression Of Renal Disease ◽  
The Impact

Dyslipidemia is a typical trait of patients with chronic kidney disease (CKD) and it is typically characterized by reduced high-density lipoprotein (HDL)-cholesterol(c) levels. The low HDL-c concentration is the only lipid alteration associated with the progression of renal disease in mild-to-moderate CKD patients. Plasma HDL levels are not only reduced but also characterized by alterations in composition and structure, which are responsible for the loss of atheroprotective functions, like the ability to promote cholesterol efflux from peripheral cells and antioxidant and anti-inflammatory proprieties. The interconnection between HDL and renal function is confirmed by the fact that genetic HDL defects can lead to kidney disease; in fact, mutations in apoA-I, apoE, apoL, and lecithin–cholesterol acyltransferase (LCAT) are associated with the development of renal damage. Genetic LCAT deficiency is the most emblematic case and represents a unique tool to evaluate the impact of alterations in the HDL system on the progression of renal disease. Lipid abnormalities detected in LCAT-deficient carriers mirror the ones observed in CKD patients, which indeed present an acquired LCAT deficiency. In this context, circulating LCAT levels predict CKD progression in individuals at early stages of renal dysfunction and in the general population. This review summarizes the main alterations of HDL in CKD, focusing on the latest update of acquired and genetic LCAT defects associated with the progression of renal disease.

Investigating the impact of off-nominal events on high-density ‘green’ arrivals

2011 ◽  
Author(s):  
Todd J. Callantine ◽  
Christopher Cabrall ◽  
Michael Kupfer ◽  
Lynne Martin ◽  
Joey Mercer ◽  
...  
Keyword(s):  
High Density ◽  
The Impact

Effect of inorganic nanofillers on the impact behavior and fracture probability of industrial high-density polyethylene nanocomposite

2017 ◽  
Vol 52 (18) ◽  
pp. 2431-2442 ◽  
Author(s):  
Harun Sepet ◽  
Necmettin Tarakcioglu ◽  
RDK Misra
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Density Polyethylene ◽  
Fracture Probability ◽  
High Density ◽  
Impact Behavior ◽  
Inorganic Filler ◽  
Melt Mixing ◽  
The Impact ◽  
Scanning Electron

The main purpose of this work is to study how the morphology of nanofillers and dispersion and distribution level of inorganic nanofiller influence the impact behavior and fracture probability of inorganic filler filled industrial high-density polyethylene nanocomposites. For this study, nanoclay and nano-CaCO3 fillers–high-density polyethylene mixings (0, 1, 3, 5 wt.% high-density polyethylene) was prepared by melt-mixing method using a compounder system. The impact behavior was examined by charpy impact test, scanning electron microscopy, and probability theory and statistics. The level of the dispersion was characterized with scanning electron microscopy energy dispersive X-ray spectroscopy analysis. The results showed rather good dispersion of both of inorganic nanofiller, with a mixture of exfoliated and confined morphology. The results indicated that the impact strength of the industrial nanocomposite decreased with the increase of inorganic particulate content. The impact reliability of the industrial nanocomposites depends on the type of nanofillers and their dispersion and distribution in the matrix.

From parallel to single crystallization kinetics in high-density amorphous ice

2013 ◽  
Vol 88 (17) ◽  
Author(s):  
Markus Seidl ◽  
Katrin Amann-Winkel ◽  
Philip H. Handle ◽  
Gerhard Zifferer ◽  
Thomas Loerting
Keyword(s):  
Crystallization Kinetics ◽  
High Density ◽  
Amorphous Ice

Convergent Raman Features in High Density Amorphous Ice, Ice VII, and Ice VIII under Pressure

2011 ◽  
Vol 115 (14) ◽  
pp. 3756-3760 ◽  
Author(s):  
Yukihiro Yoshimura ◽  
Sarah T. Stewart ◽  
Maddury Somayazulu ◽  
Ho Kwang Mao ◽  
Russell J. Hemley
Keyword(s):  
High Density ◽  
Amorphous Ice

Computerization and Occupational Change: Assessing the Impact of Automation on Racial and Gender Employment Densities

2021 ◽  
pp. 003464462110552
Author(s):  
Patrick L. Mason
Keyword(s):  
Positive Association ◽  
Racial Group ◽  
High Density ◽  
Economic Effects ◽  
Ethnic Composition ◽  
White Female ◽  
Lower Probability ◽  
Minority Men ◽  
And Gender ◽  
The Impact

The current wave of technological change is driven by automation, the process of using computers to improve the labor process, viz., increasing the quantity and quality of work “by means of computer-controlled equipment.” Automation has had and will continue to have heterogeneous economic effects across alternative social groups—altering racial and gender inequality. This study empirically examines the relationship between the racial and gender density of occupations and the probability of automation of both minor and broad occupations. Regression analysis is used to uncover correlations between future employment change and the current racial and ethnic composition of occupations, alerting us to whether future employment growth will have a negative or positive association with occupations where each racial group of workers is currently concentrated. Increases in automation are correlated with increases in labor income inequality and increases in racial and gender employment differences. Male jobs may suffer more technological unemployment than female jobs. Specifically, within each racial group high density male jobs have a greater probability of automation (and lower probability of future demand) than high density female jobs. High density White female jobs appear to be most complementary to automation, while the high density occupations of racial minority men appear to be least complementary to automation.

Abstract 260: Knockout of Apolipoprotein A-II Has Dramatic Effects on High-Density Lipoprotein Subspecies Distribution

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Scott M Gordon ◽  
Catherine A Reardon ◽  
Godfrey S Getz ◽  
W S Davidson
Keyword(s):  
Gel Filtration ◽  
Density Lipoprotein ◽  
High Density ◽  
Paraoxonase 1 ◽  
High Density Lipoproteins ◽  
Ionization Mass ◽  
Associated Proteins ◽  
Compositional Diversity ◽  
The Impact ◽  
Modest Effect

High density lipoproteins (HDL) are a highly heterogeneous population of particles composed of various lipids and proteins. They have been demonstrated to possess a diverse variety of functional properties which are thought to contribute to protection against cardiovascular disease (CVD). Proteomics studies have identified up to 75 different proteins which can associate with HDL. The basis for the compositional diversity of HDL is not known but a better understanding will yield important information about its broad functional diversity. To investigate the impact of common HDL apolipoproteins on the distribution of other apolipoproteins, we have begun to systematically fractionate plasma from various HDL apolipoprotein KO mice. Plasma from apoA-I, apoA-IV and apoA-II global KO mice was applied to gel filtration chromatography to distinguish HDL size populations. HDL particles sequestered by a phospholipid binding resin were proteomically analyzed by electrospray ionization mass spectrometry. By comparing elution volume shifts (i.e. particle size variations) for each HDL protein between WT controls and the KO models, we assessed the impact of the deleted protein on HDL size distributions. Ablation of apoA-I, while decreasing total HDL phospholipid by 70%, had a surprisingly small impact on the distribution of the majority of other HDL associated proteins - affecting only 9 of them. Genetic apoA-IV ablation had a similar modest effect shifting a distinct subset of 9 proteins. However, loss of apoA-II, in addition to causing a similar 70% reduction in overall HDL phospholipids, affected the size distribution of some 45 HDL proteins (including several complement proteins and paraoxonase-1). These data suggest that apoA-I, while associated with the majority of HDL phospholipid, may actually interact with relatively few of the lower abundance proteins known to be associated with HDL. ApoA-II on the other hand, may interact with many of these, perhaps acting as a docking site or adaptor molecule.

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