Natural Attenuation — Non-Destructive Processes

2019 ◽

Vol 262 ◽

pp. 06006

Author(s):

Aleksandra Krampikowska ◽

Anna Adamczak – Bugno

Keyword(s):

Construction Industry ◽

Frequency Analysis ◽

Raw Materials ◽

Experimental Tests ◽

Time Frequency Analysis ◽

Temperature Changes ◽

Time Frequency ◽

Destructive Processes ◽

Non Destructive ◽

Ae Signals

Modern fiber-cement boards currently used in construction are made of natural raw materials such as cement, cellulose fibers and of polyvinyl alcohol (PVA) and water. They replaced the eternitic plates, which were harmful to health, originated by Ludwig Hatschek. Materials made of fiber-cement are used in construction industry as a building and finishing material for facades, internal walls and roofs. Therefore, they are exposed to environmental conditions including rainfall and temperature changes, and in particular to frequent temperature transition through 0°C in a 24-hour cycle (cyclic freezing-thawing). In addition, fibrous cement materials, primarily used as cladding elements, are exposed to exceptional conditions, which include the high temperature caused by fire. The article presents the results of experimental tests of flexural strength of cement fiber boards subjected to exceptional conditions, to which the operation of fire belongs. The paper also presents a proposal to use a non-destructive method of acoustic emission based on time-frequency analysis for testing fiber-cement boards. Interesting research results were obtained that allowed to trace the differences in the mechanisms of material destruction under the influence of the changing time of external factors.

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Green method of stemming the tide of invasive marine and freshwater organisms by natural filtration of shipping ballast water

Environmental Science and Pollution Research ◽

10.1007/s11356-020-10839-4 ◽

2020 ◽

Author(s):

Jebarathnam Prince Prakash Jeba Kumar ◽

Shunmugavel Ragumaran ◽

Ganesan Nandagopal ◽

Vijaya Ravichandran ◽

Ramana Murthy Mallavarapu ◽

...

Keyword(s):

Ballast Water ◽

Marine Organism ◽

Green Method ◽

Freshwater Organisms ◽

Port Facilities ◽

Natural Filtration ◽

Destructive Processes ◽

Non Destructive ◽

Filtration Technology ◽

Biological Organisms

Abstract Marine and freshwater pollution caused by transport of invasive species in shipping ballast water is a major global problem and will increase in magnitude as shipping of commodities increases in the future. An economical method to preclude biological organisms in the seawater used for ballast is to exclude them at the source port. Integrated natural filtration using onshore wells or seabed gallery systems has been thoroughly investigated for use as pretreatment for seawater desalination systems and has proven to be environmentally acceptable and economic. Thus, the use of this proven filtration technology to another issue, ballast water treatment, is an innovative method of providing marine organism free seawater by non-destructive means in port-based facilities. This method is ecosystem-friendly in that no chemicals or destructive processes are used. Design and construction of well or seabed gallery intake systems for production of ballast seawater are feasible in virtually all global port facilities.

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Luminescence from individual dislocations in II-VI and III-V semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088488 ◽

1991 ◽

Vol 49 ◽

pp. 834-835

Author(s):

J W Steeds

Keyword(s):

Group Iv ◽

Luminescence Properties ◽

Carrier Recombination ◽

Transmission Electron ◽

Wide Range ◽

Basic Physics ◽

Semiconducting Compounds ◽

Diamond Group ◽

Non Destructive ◽

Technological Significance

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

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Forensic Identifications Aided by Scanning Electron Microscopy of Silicone-Epoxy Microreplicas of Calcified and Cornified Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117017 ◽

1975 ◽

Vol 33 ◽

pp. 678-679 ◽

Cited By ~ 3

Author(s):

R.F. Sognnaes

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Forensic Science ◽

George Washington ◽

Epithelial Surface ◽

Extended Application ◽

Tissue Surfaces ◽

Non Destructive ◽

Scanning Electron ◽

Surface Changes

Sufficient experience has been gained during the past five years to suggest an extended application of microreplication and scanning electron microscopy to problems of forensic science. The author's research was originally initiated with a view to develop a non-destructive method for identification of materials that went into objects of art, notably ivory and ivories. This was followed by a very specific application to the identification and duplication of the kinds of materials from animal teeth and tusks which two centuries ago went into the fabrication of the ivory dentures of George Washington. Subsequently it became apparent that a similar method of microreplication and SEM examination offered promise for a whole series of problems pertinent to art, technology and science. Furthermore, what began primarily as an application to solid substances has turned out to be similarly applicable to soft tissue surfaces such as mucous membranes and skin, even in cases of acute, chronic and precancerous epithelial surface changes, and to post-mortem identification of specific structures pertinent to forensic science.

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