Tuning multicolour emission of Zn2GeO4:Mn phosphors by Li+ doping for information encryption and anti-counterfeiting applications

2021 ◽  
Author(s):  
Dangli Gao ◽  
Kaiwei Ma ◽  
Peng Wang ◽  
Xiangyu Zhang ◽  
Qing Pang ◽  
...  

Traditional fluorescent materials used in anti-counterfeiting field usually exhibit monochromatic luminescence at a single-wavelength excitation, which is easily be forged by sophisticated counterfeiters. In this work, Zn2GeO4:Mn, x%Li (x=0 and...

2011 ◽  
Vol 380 ◽  
pp. 89-94
Author(s):  
Kun Yang ◽  
Rui Zhi Shi ◽  
Ming Xiao Wang ◽  
Xiao Zhou

With the development of fluorescent technology, the application area of fluorescent material is expanding, which includes the fields of traffic, national defence, architecture, detection, decoration etc. In the field of printing, whether in the value of utility or view and admire, fluorescent adds tremendous energies. However, a majority of fluorescent materials used nowadays contain radioelement, which will do harm to human health. This paper considers the needs of fluorescent map printing, according to the defects of traditional fluorescent material such as low brightness, short duration time, strong radioactivity, limitation to spot color printing etc. It improves the capability of long fluorescent lag material and makes red, blue, green and yellow long fluorescent lag materials. Meanwhile, it tests the influence of ink thickness, illumination time and granule size etc. on irradiance capability. The thicker the ink is, the longer of the lag time will be. The bigger the granule size is, the lag time will be. It also tests its radioactivity extent, which is in the safety range and reaches the standard of environmental protection. According to the special requirement of map printing, this paper brings forward the technique scheme of the application of long fluorescent lag ink in map printing,which realizes the color fluorescent map printing.


1996 ◽  
Vol 65 (1) ◽  
pp. 373-379 ◽  
Author(s):  
E. Bulur ◽  
H.Y. G ksu ◽  
A. Wieser ◽  
M. Figel ◽  
A.M.  zer

Author(s):  
J. Temple Black

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.


Author(s):  
W. R. Duff ◽  
L. E. Thomas ◽  
R. M. Fisher ◽  
S. V. Radcliffe

Successful retrieval of the television camera and other components from the Surveyor III spacecraft by the Apollo 12 astronauts has provided a unique opportunity to study the effects of a known and relatively extensive exposure to the lunar environment. Microstructural effects including those produced by micro-meteorite impact, radiation damage (by both the solar wind and cosmic rays) and solar heating might be expected in the materials used to fabricate the spacecraft. Samples received were in the form of 1 cm2 of painted unpainted aluminum alloy sheet from the top of the camera visor (JPL Code 933) and the sides (935,936) and bottom (934) of the lower camera shroud. They were prepared for transmission electron microscopy by first hand-grinding with abrasive paper to a thickness of 0.006". The edges were lacquered and the sample electropolished in 10% perchloric methanol using the “window” method, to a thickness of ~0.001". Final thinning was accomplished by polishing 3 mm punched disks in an acetic-phosphoric-nitric acid solution.


Author(s):  
J. Petermann ◽  
G. Broza ◽  
U. Rieck ◽  
A. Jaballah ◽  
A. Kawaguchi

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.


2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.


TAPPI Journal ◽  
2014 ◽  
Vol 13 (1) ◽  
pp. 9-19 ◽  
Author(s):  
RICARDO B. SANTOS ◽  
PETER W. HART

Brownstock washing is a complex, dynamic process in which dirty wash water or weak black liquor (dissolved organic and inorganic material obtained from the pulp cooking process) is separated from pulp fibers. The use of material balance techniques is of great importance to identify potential problems and determine how well the system is operating. The kraft pulping industry was the first known to combine pulp washing with the recovery of materials used and produced in the wood cooking process. The motivation behind materials recovery is economic, and more recently, environmentally driven. The chemicals used in the kraft process are expensive as compared to those used in the sulfite process. For the kraft process to be economically viable, it is imperative that a very high percentage of the cooking chemicals be recovered. To reach such high efficiency, a variety of washing systems and monitoring parameters have been developed. Antifoam additives and processing aids have also played an important role in increasing washing effectiveness. Antifoam materials help attain washing effectiveness by preventing entrapped air from forming in the system, which allows for an easier, unimpeded flow of filtrate through the screens and washers.


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