THE EFFECTS OF HIGH ENERGY RADIATIONS ON WATER AND AQUEOUS SYSTEMS

1948 ◽  
Vol 26b (9) ◽  
pp. 647-656 ◽  
Author(s):  
F. H. Krenz
Keyword(s):  
Hydroxyl Radicals ◽  
Indirect Effect ◽  
Active Material ◽  
Radiation Chemistry ◽  
High Energy ◽  
Biologically Active ◽  
Hydrogen Atoms ◽  
Vibrationally Excited ◽  
Production Of Hydrogen ◽  
Effects Of Radiation

Radiation chemistry is a study of the chemical effects produced by the high energy particles and quanta usually associated with nuclear mutations. When water absorbs this kind of radiation, it is decomposed into hydrogen and hydrogen peroxide. The primary act of absorption is thought to result in the production of hydrogen atoms and hydroxyl radicals which then react to give the decomposition products. In dilute aqueous solutions the effects of radiation can generally be explained from a consideration of the probable effects of hydrogen atoms and hydroxyl radicals on the solute. This is true when the solute consists of biologically active material. Since biological systems consist largely of water, the "indirect effect" that radiation has upon them through the medium of atoms and radicals produced in the water is very important. In this laboratory an attempt is being made to gain information about the "indirect effect" by investigating the properties of irradiated water. Evidence has been obtained for the production of long lived activity in irradiated water which may be attributed to vibrationally excited "polymers" of water. The extraordinary efficiency of the indirect effect" of radiation is possibly related to properties of these excited polymers.

The e.p.r. spectrum of vibrationally excited hydroxyl radicals

1971 ◽  
Vol 323 (1555) ◽  
pp. 541-554 ◽  
Keyword(s):  
Gas Phase ◽  
Hydroxyl Radicals ◽  
Hyperfine Coupling ◽  
Vibrational Energy ◽  
Theoretical Calculations ◽  
Coupling Constants ◽  
Hydrogen Atoms ◽  
Vibrationally Excited ◽  
The Matrix ◽  
Van Vleck

The e. p. r. spectrum of vibrationally excited hydroxyl radicals in levels v = 1, 2, 3 and 4 of the 2 II 3/2 ground state has been observed in the reaction between hydrogen atoms and ozone in the gas phase. Although the variation of ∧ -doubling with vibrational energy superficially agrees well with the ‘pure precession’ model of Van Vleck, there is clear evidence that the matrix element <II│ L y │ ∑> decreases considerably with increasing internuclear distance. The form of the decrease in the hyperfine coupling constants with increasing vibrational energy agrees well with that deduced from Kayama’s theoretical calculations.

ISOLEMENT ET QUELQUES CARACTERISTIQUES D'UNE GONADOTROPHINE URINAIRE DE MÉNOPAUSE HOMOGÈNE A L'ELECTROPHORÈSE

1960 ◽  
Vol XXXV (II) ◽  
pp. 225-234 ◽  
Author(s):  
R. Bourrillon ◽  
R. Got ◽  
R. Marcy
Keyword(s):  
Sialic Acid ◽  
Histological Study ◽  
Active Material ◽  
Biologically Active ◽  
New Method ◽  
Female Rats ◽  
Mouse Uterus ◽  
Highly Active ◽  
Zone Electrophoresis ◽  
Human Menopausal Gonadotrophin

ABSTRACT A new method for preparation of Human Menopausal Gonadotrophin involves successively alcoholic precipitation, kaolin adsorption and chromatography on ion exchangers. A highly active material is obtained which corresponds to 1 mg per litre of urine and has an activity of 1 mouse uterus unit at a dose of 0.003 mg. This gonadotrophin possesses both follicle stimulating and luteinizing activities in hypophysectomized female rats, by histological study. It contains 13 % hexose, 10% hexosamine and 8.5 % sialic acid. A further purification, by zone electrophoresis on starch, gives a final product, biologically active at 0.001 mg, which behaves as an homogenous substance in free electrophoresis with mobility −4.76 × 10−5 at pH 8.6.

scholarly journals Designing high energy density flow batteries by tuning active-material thermodynamics

RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5432-5443
Author(s):  
Shyam K. Pahari ◽  
Tugba Ceren Gokoglan ◽  
Benjoe Rey B. Visayas ◽  
Jennifer Woehl ◽  
James A. Golen ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Energy Storage ◽  
Energy Density ◽  
Fossil Fuels ◽  
Active Material ◽  
High Energy ◽  
Theoretical Framework ◽  
High Energy Density ◽  
Density Flow ◽  
The Cost

With the cost of renewable energy near parity with fossil fuels, energy storage is paramount. We report a breakthrough on a bioinspired NRFB active-material, with greatly improved solubility, and place it in a predictive theoretical framework.

Characterisation of Persistent Anti-Xa Activity Following Administration of the Low Molecular Weight Heparin Enoxaparin Sodium (Clexane)

1994 ◽  
Vol 72 (02) ◽  
pp. 275-280 ◽  
Author(s):  
David Brieger ◽  
Joan Dawes
Keyword(s):  
Molecular Weight ◽  
Enoxaparin Sodium ◽  
Antithrombin Iii ◽  
Anticoagulant Activity ◽  
Active Material ◽  
Biologically Active ◽  
Size Exclusion ◽  
Low Molecular Weight ◽  
Exclusion Chromatography ◽  
Liver And Kidney

SummaryIt is widely reported that persistent anti-Xa activity follows administration of low molecular weight heparins. To identify the effectors of this activity we have injected 125I-labelled Enoxaparin sodium into rabbits and subsequently analysed the circulating radiolabelled material and anti-Xa activity by affinity and size exclusion chromatography. Antithrombin III-binding material derived from the injected drug was responsible for all the anti-Xa amidolytic activity. At early times after injection additional anticoagulant activity which was largely attributable to tissue factor pathway inhibitor was measured by the Heptest clotting assay after removal of glycosaminoglycans from plasma samples. Small radiolabelled fragments, including penta/hexasaccharide with affinity for antithrombin III, were detectable in the circulation 1 week later, and sulphated oligosaccharides persisted for 3-4 weeks. Significant quantities of radiolabel remained in the liver and kidney several weeks post-injection; these organs may sequester some of the injected drug and give rise to circulating biologically active material by degradation and secretion of catabolic products into the plasma.

scholarly journals Evaluation of Antioxidative Mechanisms In Vitro and Triterpenes Composition of Extracts from Silver Birch (Betula pendula Roth) and Black Birch (Betula obscura Kotula) Barks by FT-IR and HPLC-PDA

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4633
Author(s):  
Aleksandra Ostapiuk ◽  
Łukasz Kurach ◽  
Maciej Strzemski ◽  
Jacek Kurzepa ◽  
Anna Hordyjewska
Keyword(s):  
Chemical Composition ◽  
Betula Pendula ◽  
Antioxidant Properties ◽  
Silver Birch ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Outer Bark ◽  
Betula Pendula Roth ◽  
Production Of Hydrogen ◽  
Active Substances

Silver birch, Betula pendula Roth, is one of the most common trees in Europe. Due to its content of many biologically active substances, it has long been used in medicine and cosmetics, unlike the rare black birch, Betula obscura Kotula. The aim of the study was therefore to compare the antioxidant properties of extracts from the inner and outer bark layers of both birch trees towards the L929 line treated with acetaldehyde. Based on the lactate dehydrogenase test and the MTT test, 10 and 25% concentrations of extracts were selected for the antioxidant evaluation. All extracts at tested concentrations reduced the production of hydrogen peroxide, superoxide anion radical, and 25% extract decreased malonic aldehyde formation in acetaldehyde-treated cells. The chemical composition of bark extracts was accessed by IR and HPLC-PDA methods and surprisingly, revealed a high content of betulin and lupeol in the inner bark extract of B. obscura. Furthermore, IR analysis revealed differences in the chemical composition of the outer bark between black and silver birch extracts, indicating that black birch may be a valuable source of numerous biologically active substances. Further experiments are required to evaluate their potential against neuroinflammation, cancer, viral infections, as well as their usefulness in cosmetology.

Preparation of Activated Carbon Derived from Water Hyacinth as Electrode Active Material for Li-Ion Supercapacitor

2020 ◽  
Vol 1000 ◽  
pp. 50-57
Author(s):  
Jagad Paduraksa ◽  
Muhammad Luthfi ◽  
Ariono Verdianto ◽  
Achmad Subhan ◽  
Wahyu Bambang Widayatno ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Water Hyacinth ◽  
Electrode Materials ◽  
Storage System ◽  
Active Material ◽  
Lithium Ion ◽  
High Energy ◽  
Specific Power ◽  
Full Cell ◽  
Lithium Ion Capacitor

Lithium-Ion Capacitor (LIC) has shown promising performance to meet the needs of high energy and power-density-energy storage system in the era of electric vehicles nowadays. The development of electrode materials and electrolytes in recent years has improvised LIC performance significantly. One of the active materials of LIC electrodes, activated carbon (AC), can be synthesized from various biomass, one of which is the water hyacinth. Its abundant availability and low utilization make the water hyacinth as a promising activated carbon source. To observe the most optimal physical properties of AC, this study also compares various activation temperatures. In this study, full cell LIC was fabricated using LTO based anode, and water hyacinth derived AC as the cathode. The LIC full cell was further characterized to see the material properties and electrochemical performance. Water hyacinth derived LIC can achieve a specific capacitance of 32.11 F/g, the specific energy of 17.83 Wh/kg, and a specific power of 160.53 W/kg.

scholarly journals Radiation protection in the world and in former Yugoslavia and Serbia and Montenegro since discovering of the x-rays to nowadays

2006 ◽  
Vol 4 (1) ◽  
pp. 121-132
Author(s):  
M.M. Ninkovic
Keyword(s):  
Radiation Protection ◽  
Dose Intensity ◽  
High Energy ◽  
Former Yugoslavia ◽  
General Description ◽  
X Rays ◽  
Serbia And Montenegro ◽  
Summer Schools ◽  
Effects Of Radiation ◽  
Near Future

Harmful effects of radiation and call for protection against it were recognized practically immidiatly upon the discovery of X-rays and radioactivity. A chronological review of some key events in development of radiation protection is given in this paper. First, the main activities of the ICRP since its establishment to nowadays are presented. Afterwards, a general description of some, according to the author's opinion, important events in the field of radiation protection in the former Yugoslavia and Serbia and Montenegro are given as: Vinca accident; Organization of Radiation Protection Laboratory in Vinca Institute; International Vinca Dosimetry Experiment; First Symposium and organization of the Yugoslav Radiation Protection Association; the French - Yugoslav Colloquium on radiation protection; International intercomparison experiment on nuclear accident dosimetry, and the International Summer Schools and Symposium on Radiation Protection organized in Yugoslavia. Some comments on the Three Mile Island and Chernobyl accidents are given as well. Bioindicators of low dose and dose intensity exposure are cited as one of the main problems that have to be resolved in radiation protection in the near future. Finally, as one of the main problems that, according to the author's opinion, physicists have to resolve in this field in the near future would be development of the operational dosimeter for high energy neutrons.

scholarly journals Modification of ethylene-norbornene copolymer by Gamma irradiation

2006 ◽  
Vol 60 (11-12) ◽  
pp. 311-315 ◽  
Author(s):  
Zorica Kacarevic-Popovic ◽  
Bojana Secerov ◽  
Milena Marinovic-Cincovic ◽  
Zoran Nedic ◽  
Slobodan Jovanovic
Keyword(s):  
Gamma Irradiation ◽  
Radiation Chemistry ◽  
High Energy ◽  
Spectrophotometric Analysis ◽  
New Combination ◽  
Polymeric Systems ◽  
New Class ◽  
Radiation Induced ◽  
Dsc Method ◽  
Induced Changes

The possibility of modifying polyethylene and many other polymers with high energy radiation has led to many useful applications. Due to their new combination of properties and the shortage of experimental data, the radiolysis of a new class of materials, cyclo-olefin copolymers (COC), polymerised from norbornene and ethylene using metallocene catalysts, is of great interest to the study of radiation chemistry and the physics of polymeric systems. Ethylenenorbornene copolymer, pristine and containing an antioxidant were subjected to gamma irradiation in the presence of air and in water. The irradiated copolymer was studied using IR and UV-vis spectrophotometric analysis. The radiation-induced changes in the molecular structure were correlated to changes in the glass transition temperature measured by the DSC method.

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