Organically Bound Chlorine in Marine Organisms: Chemical Properties and Possible Biochemical Origin

1991 ◽  
pp. 375-378
Author(s):  
A. Jernelov
Keyword(s):  
Chemical Properties ◽  
Marine Organisms

scholarly journals Marine-Derived Collagen as Biomaterials for Human Health

2021 ◽  
Vol 8 ◽  
Author(s):  
Ning Xu ◽  
Xue-Liang Peng ◽  
Hao-Ru Li ◽  
Jia-Xuan Liu ◽  
Ji-Si-Yu Cheng ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Chemical Properties ◽  
Extraction Methods ◽  
Marine Organisms ◽  
The Other ◽  
Physical And Chemical Properties ◽  
Fish Scales ◽  
The One ◽  
Physical And Chemical ◽  
And Chemical Properties

Collagen is a kind of biocompatible protein material, which is widely used in medical tissue engineering, drug delivery, cosmetics, food and other fields. Because of its wide source, low extraction cost and good physical and chemical properties, it has attracted the attention of many researchers in recent years. However, the application of collagen derived from terrestrial organisms is limited due to the existence of diseases, religious beliefs and other problems. Therefore, exploring a wider range of sources of collagen has become one of the main topics for researchers. Marine-derived collagen (MDC) stands out because it comes from a variety of sources and avoids issues such as religion. On the one hand, this paper summarized the sources, extraction methods and characteristics of MDC, and on the other hand, it summarized the application of MDC in the above fields. And on the basis of the review, we found that MDC can not only be extracted from marine organisms, but also from the wastes of some marine organisms, such as fish scales. This makes further use of seafood resources and increases the application prospect of MDC.

Study on Ecological and Chemical Properties of Rare Earth Elements in Tropical Marine Organisms

2016 ◽  
Vol 44 (10) ◽  
pp. 1539-1546 ◽  
Author(s):  
Jing-Xi LI ◽  
Li ZHENG ◽  
Cheng-Jun SUN ◽  
Feng-Hua JIANG ◽  
Xiao-Fei YIN ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Chemical Properties ◽  
Marine Organisms ◽  
And Chemical Properties

Modelling study of the potential release of contaminated water from storage tanks at the Fukushima Dai-ichi NPP into marine environment

2021 ◽  
Author(s):  
Vladimir Maderich ◽  
Roman Bezhenar
Keyword(s):  
Marine Environment ◽  
Nuclear Power ◽  
Nuclear Reactor ◽  
Chemical Properties ◽  
Compartment Model ◽  
Marine Organisms ◽  
Contaminated Water ◽  
Dose Coefficient ◽  
Area Of Interest ◽  
The Impact

<p>The accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in 2011 led to the uncontrolled release of a significant amount of radioactive materials into the marine environment. To prevent the further release of highly contaminated water, which was used for cooling the overheated nuclear reactor cores, and groundwater, which was continuously pumped out the reactor buildings, a large number of tanks was installed in the area around NPP to collect all this water. However, at the moment the capacity of tanks is almost exhausted. The contaminated water was processed to decrease the activity stored in the tanks, but any decontamination system cannot remove all radionuclides from the water. According to TEPCO (2020) data, about 1.2 million m<sup>3</sup> of contaminated water were stored in tanks in March 2020 containing radionuclides with long and moderate half-life, among which 10 radioisotopes (H-3, C-14, Co-60, Sr-90, Tc-99, Ru-106, Sb-125, I-129, Cs-134, Cs-137) are dominant (Buesseler, 2020). Therefore, it is important to estimate the impact on human health of potential release of contaminated water from tanks to the ocean. This impact significantly depends on the ability of radionuclides to concentrate in the marine organisms, which are in the human diet, and the values of dose coefficient. The compartment model POSEIDON-R was applied for calculation the concentration of activity in the water, bottom sediments and biota at different distances from the FDNPP. The area of interest was covered by the system of compartments with specification around FDNPP. The exchanges of activity between compartments were governed by average currents in the region. The maximal concentrations and doses were conservatively estimated for coastal box 4x4 km around the FDNPP. Accumulation of activity in the organisms was calculated by dynamical model taking into account chemical properties of the element, its role in metabolic processes and the positions of organisms in the pelagic and benthic food webs. The potential individual doses of radiation were estimated using average consumption rates of marine products in Japan based only on domestic production. The conservative scenario, when a whole volume of contaminated water will be released into the marine environment at a constant rate during 10 years, was chosen. According to results of modelling for 50 years, the obtained dose even in the coastal box turned out to be significantly lower than the maximum annual effective dose commitment for the public equal to 1 mSv (IAEA, 2011). The main contribution into the dose is expected from I-129 and C-14. Although the activity of tritium (H-3) far exceeds activities of other radionuclides in tanks, its contribution to the total dose is only third due to low ability to concentrate in organisms and low dose coefficient. The dose factors and activity factors for 10 radionuclides at different distances from the FDNPP were obtained to be used for estimation of doses to human and concentration of activities in marine organisms for any long-lasting release scenario.</p>

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments

1974 ◽  
Vol 32 ◽  
pp. 262-263
Author(s):  
Sydney S. Breese ◽  
Howard L. Bachrach
Keyword(s):  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Distilled Water ◽  
Bovine Plasma ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Carbon Coated ◽  
Rna Fragments ◽  
Physical And Chemical

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.

Decoration of specific sites on freeze-fractured membranes

1978 ◽  
Vol 36 (2) ◽  
pp. 140-141
Author(s):  
H. Gross ◽  
H. Moor
Keyword(s):  
Pure Water ◽  
Freeze Fracture ◽  
Chemical Properties ◽  
Surface Forces ◽  
Sulfate Pentahydrate ◽  
Copper Sulfate Pentahydrate ◽  
Physico Chemical ◽  
Water Of Hydration ◽  
Small Container ◽  
Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

Cathodoluminescence of Catalyst Crystallites

1982 ◽  
Vol 40 ◽  
pp. 664-665
Author(s):  
E.D. Boyes ◽  
P.L. Gai ◽  
D.B. Darby ◽  
C. Warwick
Keyword(s):  
Defect Density ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Semiconductor Materials ◽  
Environmental Cell ◽  
High Resolution Structure ◽  
Commercially Important ◽  
Crystallographic Defects ◽  
Resolution Structure

The extended crystallographic defects introduced into some oxide catalysts under operating conditions may be a consequence and accommodation of the changes produced by the catalytic activity, rather than always being the origin of the reactivity. Operation without such defects has been established for the commercially important tellurium molybdate system. in addition it is clear that the point defect density and the electronic structure can both have a significant influence on the chemical properties and hence on the effectiveness (activity and selectivity) of the material as a catalyst. SEM/probe techniques more commonly applied to semiconductor materials, have been investigated to supplement the information obtained from in-situ environmental cell HVEM, ultra-high resolution structure imaging and more conventional AEM and EPMA chemical microanalysis.

Defects in Crystals

1968 ◽  
Vol 26 ◽  
pp. 244-245
Author(s):  
Kenneth R. Lawless
Keyword(s):  
Electron Microscope ◽  
Point Defects ◽  
Surface Defects ◽  
Chemical Properties ◽  
Material Point ◽  
Crystal Defects ◽  
Defects In Crystals ◽  
Irradiation Effects ◽  
Normal Lattice ◽  
Line Defects

One of the most important applications of the electron microscope in recent years has been to the observation of defects in crystals. Replica techniques have been widely utilized for many years for the observation of surface defects, but more recently the most striking use of the electron microscope has been for the direct observation of internal defects in crystals, utilizing the transmission of electrons through thin samples.Defects in crystals may be classified basically as point defects, line defects, and planar defects, all of which play an important role in determining the physical or chemical properties of a material. Point defects are of two types, either vacancies where individual atoms are missing from lattice sites, or interstitials where an atom is situated in between normal lattice sites. The so-called point defects most commonly observed are actually aggregates of either vacancies or interstitials. Details of crystal defects of this type are considered in the special session on “Irradiation Effects in Materials” and will not be considered in detail in this session.

In Situ microscopy of the anodic etching of silicon

1995 ◽  
Vol 53 ◽  
pp. 232-233
Author(s):  
Frances M. Ross ◽  
Peter C. Searson
Keyword(s):  
Composite Structures ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Selective Etching ◽  
Silicon On Insulator ◽  
Second Phase ◽  
Porous Layers ◽  
New Class ◽  
Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

The microstructure of a TiB2/Ti-47 Al composite material

1989 ◽  
Vol 47 ◽  
pp. 674-675
Author(s):  
O. Popoola ◽  
A.H. Heuer ◽  
P. Pirouz
Keyword(s):  
Composite Material ◽  
Ion Beam ◽  
Chemical Properties ◽  
Intermetallic Alloys ◽  
Transmission Electron ◽  
Diamond Polishing ◽  
Al Composite ◽  
The Matrix ◽  
Argon Ion ◽  
And Chemical Properties

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.

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