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This paper presents the development of a method for dual-energy processing of X-ray images using pulsed X-ray sources for the contrast detection of beryl in muscovite mica in 2D X-ray and CT images. These substances have similar chemical properties and are difficult to differentiate when one is against the background of the other using methods based on X-ray absorption. In the experiments, we used three pulsed X-ray sources with different maximum voltages. We performed modeling of the emission spectra and selection of the necessary energy bands due to X-ray absorbing filters: a positive effect was shown for dual-energy image processing when the function of converting X-ray radiation into a signal using the VIVIX-V 2323D detector was taken into account. As a result, a pulsed X-ray source with the pulse voltage of 330 kV was chosen for the contrast detection of beryl, with the content of 5-7% against the background of muscovite and the thickness up to 70 mm. Using this source and the developed mathematical algorithms, it is possible to obtain a band of low-energy radiation at the level of 70-80 keV, as well as high-energy radiation in the range of 180 keV. Methods based on the X-ray absorption can become both additional and independent methods for studying and monitoring membranes; these objects range from tens of nanometers to several micrometers in size.
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Beryl in different varieties (emerald, aquamarine, heliodor etc.) displays a wide range of colours that have fascinated humans throughout history. Beryl is a hexagonal cyclo-silicate (ring-silicate) with channels going through the crystal along the c-axis. The channels are about 0.5 nm in diameter and can be occupied by water and alkali ions. Pure beryl (Be3 Al2 Si6 O18 ) is colourless (variety goshenite). The characteristic colours are believed to be mainly generated through substitutions with metal atoms in the lattice. Which atoms that are substituted is still debated it has been proposed that metal ions may also be enclosed in the channels and that this can also contribute to the crystal colouring. So far spectroscopy studies have not been able to fully answer this. Here we present the first experiments using atomic resolution scanning transmission electron microscope imaging (STEM) to investigate the channel occupation in beryl. We present images of a natural beryl crystal (variety heliodor) from the Bin Thuan Province in Vietnam. The channel occupation can be visualized. Based on the image contrast in combination with ex situ element analysis we suggest that some or all of the atoms that are visible in the channels are Fe ions.
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Commercial 9Be solutions used for chemical preparation of samples for accelerator mass spectrometry contain the cosmogenic long-lived radionuclide 10Be at elevated but different 10Be/9Be levels. Within a systematic study of recently produced solutions, comparison to published data and new data on customised solutions from minerals, we recommend - if no customised solution is available - the 9Be solutions from Australian Chemical Reagents (ACR) or from LGC. They contain 10Be/9Be at the 3.4 × 10-15 level, which is still suitable for the majority of Earth science applications, compared to customised solutions at the 10-16 level for lowest-level studies. Commercial solutions from Scharlab having different lot numbers, i.e. an identification number assigned to a particular lot of material from a single manufacturer, vary in 10Be/9Be by up to a factor of nine. Hence, it seems an advisable strategy to buy a bigger quantity of a single production batch (such as 10 × 100 ml bottles of 9Be at 1 g l-1) and have them tested once at any AMS facility before first use.â¢The best 9Be carrier for low-level 10Be/9Be applications is a customised one from minerals like phenakite.â¢The best 9Be carriers for medium- and high-level 10Be/9Be applications are currently from Australian Chemical Reagents (ACR) or from LGC.â¢As 9Be carriers from Scharlab of different batches (LOT) contain 10Be/9Be at different levels, it is advisable to buy a bigger number of bottles of the same LOT of commercial carriers after being identified to have reasonably low isotope ratios.
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Ilex 'Beryl' is an ornamental and ecological tree widespread in southeastern China. In this study, the complete chloroplast (cp) genome of Ilex 'Beryl' was assembled and characterized to investigate its phylogenetic relationship. The entire cp genome of 'Beryl' was a typical quadripartite structure with 157,575 bp in length, including a large single-copy (LSC) region of 87,080 bp and a small single-copy (SSC) region of 18,427 bp, which were separated by a pair of inverted repeats (IRs) of 52,068 bp. There are 135 genes annotated, including 90 protein-coding genes, eight rRNA genes and 37 tRNA genes. Phylogenetic analysis based on whole cp genome sequences showed that 'Beryl' is closest to I. 'Emily Bruner' and I. 'tall boy'.
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BACKGROUND:In oral warm and moisture circumstance, al oy which contains Be is easily to be eroded to release Be2+. But there is stil no research focusing on beryl ium influence on genotype of Porphyromonas gingivalis fimbriae gene cluster. OBJECTIVE:To investigate Be 2+effect on genotype of Porphyromonas gingivalis fimbriae gene cluster. METHODS:The revived Porphyromonas gingivalis was resuscitated for 48 hours in the anaerobic culture medium with different concentration of Be 2+(10×10-6, 5×10-6, 1.25×10-6). Through PCR amplification and sequencing, we investigated the effects of Be2+RESULTS AND CONCLUSION:(1) When Be on genotypes of Porphyromonas gingivalis fimbriae gene cluster. 2+concentration was 5×10-6, we found the peak of 217 and 257 sites on DNA sequence expressing G/A overlap peak, different from G single peak of the other groups, suggesting the suspicious bases changes, part of the single base G mutated into A. (2) On al concentrations, we found a base group composed of seven A bases was inserted into the 101 site of DNA sequence. Up to now, there is no direct contacts of the mutations occurring to Be2+concentration. Changes of gene may lead to the shifting of the reading frame, the abnormal synthesis of proteins, the change of Porphyromonas gingivalis fimA gene toxicity, and lastly the unbalance of the micro-ecological environment.