scholarly journals THE TREATMENT OF FRACTURES OF THE NECK OF THE FEMUR BY IMMEDIATE REDUCTIO AND PERMANENT FIXATION.

JAMA ◽  
1889 ◽  
Vol XIII (5) ◽  
pp. 150 ◽  
Author(s):  
N. SENN
Keyword(s):  
Permanent Fixation

Adaptive radiation of the comatulid crinoids

Paleobiology ◽  
1977 ◽  
Vol 3 (1) ◽  
pp. 74-82 ◽  
Author(s):  
David L. Meyer ◽  
Donald B. Macurda
Keyword(s):  
Habitat Selection ◽  
Shallow Water ◽  
Adaptive Radiation ◽  
Late Mesozoic ◽  
Behavioral Adaptations ◽  
Bony Fishes ◽  
Survival Capacity ◽  
Stalked Crinoids ◽  
Permanent Fixation

Modern crinoids are dominated by the comatulids (unstalked forms) which range from the intertidal to abyssal depths. Modern stalked crinoids are restricted to depths greater than about 100 m. In the geologic past some stalked crinoids lived at depths of a few tens of meters or less in reef and bank environments. The primary vehicles postulated for the post-Triassic radiation of comatulids are lack of permanent fixation to the substratum and the capacity for mobility. Development of complex muscular articulations has enabled crawling or swimming which serve in habitat selection and avoidance of stress and predators. These and other adaptations may have bestowed on comatulids a higher survival capacity in shallow-water environments compared to stalked crinoids. Modern stalked crinoids lack mobility and complex behavioral adaptations seen in comatulids. Possibly, stalked crinoids in shallow water were unable to cope with the radiation of abundant, predaceous bony fishes in the late Mesozoic and became restricted to greater depths while the more adaptable comatulids gained ascendancy in shallow water.

Stress Relaxation of Sugi (Cryptomeria japonica D.Don) Wood in Radial Compression under High Temperature Steam

Holzforschung ◽  
1999 ◽  
Vol 53 (5) ◽  
pp. 541-546 ◽  
Author(s):  
W. Dwianto ◽  
T. Morooka ◽  
M. Norimoto ◽  
T. Kitajima
Keyword(s):  
High Temperature ◽  
Stress Relaxation ◽  
Cryptomeria Japonica ◽  
Chain Scission ◽  
Strain Recovery ◽  
Crystalline Lattice ◽  
Compressive Deformation ◽  
Radial Compression ◽  
Stress Strain ◽  
Permanent Fixation

Summary To clarify the mechanism of the permanent fixation of compressive deformation of wood by high temperature steaming, stress relaxation and stress-strain relationships in the radial compression for Sugi (Cryptomeria japonica D.Don) wood were measured under steam at temperatures up to 200°C. The stress relaxation curves above 100°C were quite different in shape from those below 100°C, showing a rapid decrease in stress with increasing temperature. In the stress-strain relationships measured above 140°C, the stress reduced as pre-steaming time increased when compared at the same strain. The recovery of compressive deformation (strain recovery) was decreased with steaming time and reached almost 0 in 10 min at 200°C. The relationship between the residual stress and the strain recovery at the end of relaxation measurements could be expressed by a single curve regardless of time and temperature. The permanent fixation of deformation by steaming below 200°C was considered to be due to chain scission of hemicelluloses accompanying a slight cleavage of lignin. In some cases, the increase in regularity of the crystalline lattice space of microfibrils or the formation of crosslinks between the cell wall polymers seemed to play an important role in the permanent fixation of compressive deformation.

Sequestration of supercritical CO2 by mercury oxide

2013 ◽  
Vol 67 (6) ◽  
Author(s):  
Kledi Xhaxhiu ◽  
Erisa Saraçi ◽  
Klaus Bente
Keyword(s):  
Fly Ash ◽  
Binary System ◽  
Flue Gas ◽  
Supercritical Co2 ◽  
Power Plants ◽  
Laboratory Method ◽  
Mercury Oxide ◽  
Permanent Fixation ◽  
Waste Incinerators ◽  
Geological Formations

AbstractHgCO3·2HgO (mercury oxide carbonate), along with partly unreacted reactants, was obtained by exploring the behaviour of the Hg2Cl2/HgO binary system in supercritical CO2 (scCO2) at 200°C, 22000 kPa in the presence and absence of water, using a self-made laboratory-scale system. The reaction of pure HgO with scCO2 aimed at the synthesis of HgCO3 (mercury carbonate), also yielded the same product. Meanwhile, with a small amount of water present in the Hg2Cl2/HgO-scCO2 system, at 200°C, 22000 kPa, the mineral terlinguaite (Hg4O2Cl2) was obtained instead of mercury oxide carbonate. Repeating this reaction under the same conditions, but in the absence of CO2, again resulted in the synthesis of terlinguaite, leading to the assumption that the scCO2 had no influence on the synthesis of terlinguaite. This study reveals a new moisture-free laboratory method and conditions for the permanent fixation of CO2 by HgO. This method bears two benefits: 1) it can be introduced to reduce the Hg content in flue gas and fly ash emitted from coal-burning power plants and municipal waste incinerators; 2) it can contribute to CO2 mineralisation in montroydite (HgO) geological formations as mercury oxide carbonate.

The effect of bacterial films on the temporary adhesion and permanent fixation of cypris larvae,balanus amphitritedarwin

Biofouling ◽  
1994 ◽  
Vol 8 (2) ◽  
pp. 121-131 ◽  
Author(s):  
J S Maki ◽  
A B Yule ◽  
D Rittschof ◽  
R Mitchell
Keyword(s):  
Bacterial Films ◽  
Permanent Fixation

Peningkatan Kerapatan Kayu Samama Melalui Pre-kompresi Asam Sitrat (Density Improvement of Samama Wood by Pre-compression of Citric Acid)

2021 ◽  
Vol 17 (2) ◽  
pp. 122-133
Author(s):  
Azis Rumbaremata ◽  
Tekat D Cahyono ◽  
Teguh Darmawan ◽  
Sukma S Kusumah ◽  
Fazhar Akbar ◽  
...  
Keyword(s):  
Citric Acid ◽  
Acid Concentration ◽  
Aluminum Foil ◽  
Dry Density ◽  
Citric Acid Concentration ◽  
Pressing Time ◽  
R Ratio ◽  
Permanent Fixation ◽  
Water Saturated ◽  
Temperature Time

Samama wood (Anthocephalus macrophyllus (Roxb.) Havil.) is a potential fast-growing species of Sulawesi and Maluku. This study aimed to increase the density of the wood through citric acid pre-compression. The temperature/time pressing formula and the optimal concentration of citric acid for fixation were also determined. Water saturated samples of (5x5x4) cm3 (L = longitudinal x T = tangential x R = radial) were pre-compressed at 100 °C for one hour to reach drying set. Subsquently, the samples were soaked for 4 hours in a citric acid solution of 5% and 10% concentration, drained and wrapped in aluminum foil before re-pressed at 180 °C for 10, 20, 30, 40, 50, and 60 minutes. Fixation was measured by soaking the samples into water for 24 hours at room temperature. The results showed that the moisture contents at fiber saturation point ranged from 33.15-33.94%, with density of 0.46 g cm-3 and oven dry density of 0.37 g cm-3. The L, T, and R shrinkages were 0.18-0.20%, 4.13-4.14%, and 2.53-3.10%, respectively; while the T/R ratio was 1.33-1.63%. Pre-compression can only be done at a compression target of 25% with compression level of 19.57-20.01%. Pre-compression increased the oven dry density of 17.11-20.13% to 0.44-0.45 g cm-3. After thickness recovery, the weight of the oven dried samples increased by 1.79-2.72% at the 5% citric acid concentration and by 12.04-15.25% at the 10% citric acid concentration.  Permanent fixation achieved at 180 °C for 50 minutes pressing time with 10% citric acid concentration.

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