FDM analysis of ultrasonic nonlinearity in partially degraded material

Author(s):  
K.C. Kim ◽  
H. Yamawaki ◽  
T. Saito ◽  
K.Y. Jhang
Keyword(s):  
Nanoscale ◽  
2017 ◽  
Vol 9 (37) ◽  
pp. 13938-13946 ◽  
Author(s):  
C. Polop ◽  
E. Vasco ◽  
A. P. Perrino ◽  
R. Garcia

From aircraft to electronic devices, and even in Formula One cars, stress is the main cause of degraded material performance and mechanical failure in applications incorporating thin films and coatings.


1970 ◽  
Vol 116 (1) ◽  
pp. 27-34 ◽  
Author(s):  
U. Lindahl

(1) Polysaccharides were isolated from bovine liver capsule by extraction with 2m-potassium chloride followed by precipitation from 0.8m-potassium chloride with cetylpyridinium chloride. Chondroitin sulphate was eliminated by digestion with hyaluronidase. The yield of heparin was approx. 40% of that obtained after extraction of the papain-digested tissue. (2) The macromolecular properties of the hyaluronidase-digested polysaccharide were studied by gel chromatography on Sephadex G-200 of the intact, as well as of the alkali-degraded, material. The results suggested the presence of single heparin chains in addition to a dermatan sulphate proteoglycan. (3) A purified heparin preparation was analysed for amino acids and neutral sugars. Xylose, galactose and serine were found in amounts corresponding to 0.1, 0.2, and 0.4 residue/polysaccharide chain (mol.wt. 7400), respectively. It is suggested that the isolated material had been degraded by a polysaccharidase with endo-enzyme properties.


2014 ◽  
Vol 11 (12) ◽  
pp. 3299-3305 ◽  
Author(s):  
C. Rumpel ◽  
V. Chaplot ◽  
P. Ciais ◽  
A. Chabbi ◽  
B. Bouahom ◽  
...  

Abstract. In order to assess whether eroded carbon is a net source or sink of atmospheric CO2, characterisation of the chemical composition and residence time of eroded organic matter (EOM) at the landscape level is needed. This information is crucial to evaluate (1) how fast EOM can be decomposed by soil microbes during its lateral transport and (2) its impact at deposition sites. This study considers a continuum of scales to measure the composition of EOM across a steep hillslope landscape of the Mekong basin with intense erosion. We sampled suspended sediments eroded during rainfall events from runoff plots (1 and 2.5 m2) and the outlets of four nested watersheds (0.6 × 104 to 1 × 107 m2). Here we show that changes in the chemical composition of EOM (measured by nuclear magnetic resonance spectroscopy) and in its 13C and 15N isotope composition from plot scale through to landscape scale provide consistent evidence for enrichment of more decomposed EOM across distances of 10 km. Between individual soil units (1 m2) to a small watershed (107 m2), the observed 28% decrease of the C/N ratio, the enrichment of 13C and 15N isotopes as well as O-alkyl C in EOM is of similar magnitude as changes recorded with depth in soil profiles due to soil organic matter "vertical" decomposition. Radiocarbon measurements indicated ageing of EOM from the plot to the watershed scale. Therefore transport of EOM may lead to enrichment of stabilised soil organic matter compounds, eventually being subject to export from the watershed.


2018 ◽  
Vol 18 (2) ◽  
pp. 211
Author(s):  
Arini Wresta ◽  
Aep Saepudin

Biogas resulted from anaerobic digestion of organic compounds have various methane content depend on the type of the degraded material. The methane content of biogas is range between 40–80% that influence the heating value and combustion characteristic of that biogas. The higher methane content can be obtained through upgrading biogas by removing CO2 and other trace components like H2S, NH3, and water vapor. This research was a simulation of product composition and temperature of biogas combustion in various methane content and air biogas equivalence ratio. Biogas combustion was done in combustion chamber at constant pressure of 1 atm. Biogas and air enter into combustion chamber at temperature approximately of 30 °C as the common ambient temperature in Indonesia. The input air was designed higher than stoichiometric need in order to reach complete combustion. Combustion reaction between methane and O2 then carried out in the combustion chamber to produce CO2 and H2O. The product gases consisting of CO2, H2O, N2, and excess O2, bring heat from combustion reaction and exit from combustion chamber at the higher temperature. The analysis was done for methane content range between 20 and 100% with air biogas equivalence ratio from 1 until 3. The simulation result showed that for V m3 biogas, the combustion gases could reach 0.12271 until 1.26798V gmol with temperature above 700 °C until above 1900 °C. More than 50% component in the combustion gases is N2 as inert material from input air to combustion chamber.


1963 ◽  
Vol 117 (4) ◽  
pp. 561-571 ◽  
Author(s):  
Louis Chedid ◽  
Robert C. Skarnes ◽  
Monique Parant

The incubation of endotoxin with Na2Cr51O4 yielded a product which was well labeled. That the label was fixed on the endotoxin itself was shown by autoradiography on specific lines of precipitation formed in agar. Ultracentrifugation at 40,000 RPM sedimented 80 per cent of the total weight of the starting Boivin preparation. Agar diffusion patterns with subsequent autoradiographs demonstrated that the chromium tag was associated only with the heavy fractions of the pellet. The supernatant contained precipitable, but unlabeled endotoxin. Toxicity measurements showed that more than 99 per cent of the total toxicity resided in the pellet fractions. The chromate-tagged endotoxin was specifically identified in plasma samples taken up to 6 hours after intravenous administration of LD50 or sublethal doses. The endotoxin was not totally detoxified in vivo since plasma collected 6 hours after the injection of even the sublethal dose was toxic when assayed in adrenalectomized mice. The endotoxin was specifically identified in urine specimens but it was no longer toxic or radioactive. Agar diffusion experiments indicated that only degraded material was present.


2019 ◽  
Vol 20 (4) ◽  
pp. 901 ◽  
Author(s):  
Stefano Thellung ◽  
Alessandro Corsaro ◽  
Mario Nizzari ◽  
Federica Barbieri ◽  
Tullio Florio

The aim of this review is to critically analyze promises and limitations of pharmacological inducers of autophagy against protein misfolding-associated neurodegeneration. Effective therapies against neurodegenerative disorders can be developed by regulating the “self-defense” equipment of neurons, such as autophagy. Through the degradation and recycling of the intracellular content, autophagy promotes neuron survival in conditions of trophic factor deprivation, oxidative stress, mitochondrial and lysosomal damage, or accumulation of misfolded proteins. Autophagy involves the activation of self-digestive pathways, which is different for dynamics (macro, micro and chaperone-mediated autophagy), or degraded material (mitophagy, lysophagy, aggrephagy). All neurodegenerative disorders share common pathogenic mechanisms, including the impairment of autophagic flux, which causes the inability to remove the neurotoxic oligomers of misfolded proteins. Pharmacological activation of autophagy is typically achieved by blocking the kinase activity of mammalian target of rapamycin (mTOR) enzymatic complex 1 (mTORC1), removing its autophagy suppressor activity observed under physiological conditions; acting in this way, rapamycin provided the first proof of principle that pharmacological autophagy enhancement can induce neuroprotection through the facilitation of oligomers’ clearance. The demand for effective disease-modifying strategies against neurodegenerative disorders is currently stimulating the development of a wide number of novel molecules, as well as the re-evaluation of old drugs for their pro-autophagic potential.


2014 ◽  
Vol 225 ◽  
pp. 39-44
Author(s):  
Alexander Balitskii ◽  
Myhajlo Semerak ◽  
Walentyna Balitska ◽  
Andriy Subota ◽  
Oleh Wus

It is experimentally established that air-tested samples of degraded material showed tooth flow that disappears for tests in hydrogen. The main feature inherent in the studied materials are metastable and presence of more or less pronounced time-and temperature-dependent processes of structural relaxation, which reduces the total free energy of a thermodynamic system. The values of fracture toughness minimize the square deviation of experimentally obtained values drift from the theoretical curve corresponding to the exponential relaxation function.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Micaela Ebert ◽  
Juergen Ebert ◽  
Gerd Berger

Treatment efficacy in cancer patients using systemically applied cytostatic drugs is decreased by cytotoxic side effects, which limits the use of efficient dosages. Degradable starch microspheres (DSM) are used to apply drugs into blood vessels which supply the target organ leading to drug accumulation in the target organ by reduction of the blood flow. The present investigations show that DSM is a very effective embolization material leading to effective and enhanced accumulation of 5-FU within the liver tumor tissue of experimental induced liver cancer in rats. By using intravital microscopy, a rapid deceleration of the blood flow into the target organ is observed immediately after application of DSM. The microspheres are stepwise degraded in the direction of the systemic blood flow and are totally dissolved after 25 minutes. These stepwise processes leave the degraded material during the degradation process within the vessels leading to temporally reciprocal blood flow via some of the side-arms of the major blood vessels. By using DMS in transarterial chemoembolization (TACE), severe adverse side effects like postembolization syndrome are rarely observed when compared to other embolization materials. The complete degradation of DSM causes only a short-lasting temporary vascular occlusion, which allows a repeat application of DSM in TACE.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Pei Sun Loh ◽  
Chen-Tung Arthur Chen ◽  
Gusti Z. Anshari ◽  
Jiann-Yuh Lou ◽  
Jough-Tai Wang ◽  
...  

This study assessed the sedimentary organic matter (OM) and phosphate along the world’s longest river on an island: the Kapuas River in West Kalimantan, Indonesia. The surface sediment was tested using the loss-on-ignition experiment to determine the % labile OM, % refractory OM, and % total OM and the Rp values (the ratio of refractory to total OM). The C/N ratios and the inorganic phosphate (IP), organic phosphate (OP), and total phosphate (TP) levels were also determined. The combination of high Rp values and low C/N ratios along the upper river indicated the possible presence of relatively degraded material; the low Rp values and high C/N ratios downstream were indicative of a fresher terrestrial signal. Sedimentary P levels were the highest along the densely populated areas downstream from the Kapuas River; the second highest along the midstream river, which is surrounded by oil palm plantations; and the lowest along the upper river, which is surrounded by forest. Higher levels of OM, IP, OP, and TP downstream along the Kapuas River indicated the presence of anthropogenic sources of OM and P.


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