crystal arrangement
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2021 ◽  
Vol 6 (5) ◽  
pp. 181-189
Author(s):  
C. Raveendiran ◽  
P. Prabukanthan

Heterocyclic organic nonlinear optical materials of N-(1,3-benzothiazol-2-yl)benzamide [2-BTBA] and N-(1,3-benzothiazol-2-yl)-2-fluorobenzamide [2-BTFBA] were orchestrated by benzoylation of 2-aminobenzothiazole utilizing subbed benzoyl chloride. The orchestrated mixtures2-BTBA and 2-BTFBA molecular ion peaks at 253.9 & 272 were affirmed by GC-MS. The grown single crystals of 2-BTBA and 2-BTFBA were developed by slow evaporation method at room temperature with a combination of ethyl acetate & methanol as dissolvable. The X-ray diffraction investigations of equally 2-BTBA & 2-BTFBA crystal have a monoclinic framework with space group P21/n individually. The FT-IR spectra of 2-BTBA and 2-BTFBA show absorption peaks at 1670 and 1660 cm-1, indicating the presence of carbonyl functional group vibration modes in the molecules. UV–Vis spectra show a awesome absorbance band at 303 & 300 nm for 2-BTBA and 2-BTFBA molecules, respectively. The number of protons and carbons were predicted using 1H and 13C NMR spectrum studies. TGA and DTA analyses confirmed the various stages of disintegration of the produced crystals, and they are thermally stable up to 403 K and 333 K for 2-BTBA and 2-BTFBA, respectively. The zone of hindrance method was used to test the antibacterial and antifungal activities of produced single crystals using amphotericin-B and ciprofloxacin as standards. The outcomesprove that the incorporated mixtures display prevalent anti-fungal and antibacterial activity. The non-linear efficiency was affirmed by Kurtz- Perry concentrates trategy for 2-BTBA and 2-BTFBA crystals with the SHG proficiency 2.28 and 2.83 times more prominent than that of potassium dihydrogen phosphate [KDP].


2020 ◽  
Vol 117 (21) ◽  
pp. 11217-11219 ◽  
Author(s):  
Lee F. White ◽  
Kimberly T. Tait ◽  
Brian Langelier ◽  
Elizabeth A. Lymer ◽  
Ana Černok ◽  
...  

Understanding the timing and mechanisms of amino acid synthesis and racemization on asteroidal parent bodies is key to demonstrating how amino acids evolved to be mostly left-handed in living organisms on Earth. It has been postulated that racemization can occur rapidly dependent on several factors, including the pH of the aqueous solution. Here, we conduct nanoscale geochemical analysis of a framboidal magnetite grain within the Tagish Lake carbonaceous chondrite to demonstrate that the interlocking crystal arrangement formed within a sodium-rich, alkaline fluid environment. Notably, we report on the discovery of Na-enriched subgrain boundaries and nanometer-scale Ca and Mg layers surrounding individual framboids. These interstitial coatings would yield a surface charge state of zero in more-alkaline fluids and prevent assimilation of the individual framboids into a single grain. This basic solution would support rapid synthesis and racemization rates on the order of years, suggesting that the low abundances of amino acids in Tagish Lake cannot be ascribed to fluid chemistry.


Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2726 ◽  
Author(s):  
Mikhail Y. Vorona ◽  
Nathan J. Yutronkie ◽  
Owen A. Melville ◽  
Andrew J. Daszczynski ◽  
Kwame T. Agyei ◽  
...  

Anthracene-based semiconductors are a class of molecules that have attracted interest due to their air stability, planarity, potential for strong intermolecular interactions, and favorable frontier molecular orbital energy levels. In this study seven novel 9,10-anthracene-based molecules were synthesized and their optical, electrochemical, and thermal properties were characterized, along with their single crystal arrangement. We found that functionalization of the 9,10-positions with different phenyl derivatives resulted in negligible variation in the optical properties with minor (±0.10 eV) changes in electrochemical behavior, while the choice of phenyl derivative greatly affected the thermal stability (Td > 258 °C). Preliminary organic thin film transistors (OTFTs) were fabricated and characterized using the 9,10-anthracene-based molecules as the semiconductor layer. These findings suggest that functionalization of the 9,10-position of anthracene leads to an effective handle for tuning of the thermal stability, while having little to no effect on the optical properties and the solid-state arrangement


2019 ◽  
Vol 14 (4) ◽  
pp. 616-622 ◽  
Author(s):  
Aika K. Kurokawa ◽  
Takahiro Miwa ◽  
Hidemi Ishibashi ◽  
◽  

In this study, a procedure to measure the viscosity of multi-phase magma at high temperatures (>1000°C) was developed by using a simple apparatus comprising a commercially available desktop furnace and viscometer. In particular, the use of a disposable container enabled observations of the microstructure of an entire sample. The procedure was applied to basaltic andesite magma of the 1986 Izu–Oshima fissure eruption, Japan. The results show that reliable data, consistent with previous studies, were obtained and that the magma rheology became non-Newtonian with decreasing temperature, showing clear shear-thinning behavior. The rheological properties of the magma at 1180°C are quantitatively described as a function of shear rate based on three simple non-Newtonian fluid models. Sectional views of the sample confirm that plagioclase and Fe–Ti oxide crystals were nearly uniformly dispersed in the sample. The mean crystal volume fraction of 0.14 enabled crystal interactions inducing changes in crystal arrangement, affecting the rheology.


2019 ◽  
Vol 52 (1) ◽  
pp. 115-121 ◽  
Author(s):  
Albert Macrander ◽  
Nino Pereira ◽  
Christian Stoeckl ◽  
XianRong Huang ◽  
Elina Kasman

A large α-quartz crystal designed to condition the monochromatic beam at beamline 1-BM of the Advanced Photon Source is presented. The purpose of this crystal was to provide a precise match to the Bragg angle of quartz crystals that are commonly used to make analyzers for plasma diagnostics. In order to characterize these analyzers, area detectors need to be positioned at distances from the analyzer at upwards of 1000 mm. As a result of this precise matching, a Bragg-reflected beam from such an analyzer is precisely parallel to the beam incident on the conditioning crystal. This situation alleviates the need to adjust the position of the area detector as the distance between the analyzer and the area detector is varied. That is, there is no need to account for vertical displacement of the diffracted-beam image as a function of this distance. Additionally, verification that the analyzer is set to the correct Bragg reflection is obtained by scanning this distance, because only for a spurious reflection will there be a vertical displacement. This is a very useful check. To commission the conditioning crystal, diffraction from a high-quality flat quartz crystal was mapped using a CCD. Bragg diffraction from the 40\overline 40 reflection at 8.5 keV was studied over an area of 23 × 31 mm. The theoretical Darwin width of the flat sample in this case was 4.7 µrad. An FWHM value near 6 µrad was measured over almost the entire mapped area. These data demonstrate that the resolution function for this four-crystal arrangement is ∼4 µrad. Data are also presented for a 0.1 mm-thick α-quartz wafer pressed into a concave form, having a nominal radius of 500 mm and intended for use as an analyzer. Because analyzers are bent crystals, diffraction occurs in narrow bands. When a multiple exposure is made as a function of rocking angle a striped pattern is obtained, which is commonly referred to as a zebra-stripe pattern. A series of zebra stripes from the 30\overline 3\overline 3 Bragg reflection of the bent wafer over its 25 mm-diameter area were recorded on a CCD. The zebra-stripe pattern was analyzed to show a uniform bending to a radius of 497.0 ± 0.3 mm, in support of the nominal value. An r.m.s. slope error of 7 µrad was also obtained from this analysis.


2018 ◽  
Vol 57 (29) ◽  
pp. 8614
Author(s):  
Markus Selmke ◽  
Sarah Selmke
Keyword(s):  

2018 ◽  
Vol 74 (4) ◽  
pp. 428-436 ◽  
Author(s):  
Mónica I. García-Aranda ◽  
Carlos Z. Gómez-Castro ◽  
Efrén V. García-Báez ◽  
Yolanda Gómez y Gómez ◽  
José L. Castrejón-Flores ◽  
...  

A detailed structural analysis of the benzimidazole nitroarenes 1-(4-nitrophenyl)-1H-1,3-benzimidazole, C13H9N3O2, (I), 1-(4-nitrophenyl)-2-phenyl-1H-1,3-benzimidazole, C19H13N3O2, (II), and 2-(3-methylphenyl)-1-(4-nitrophenyl)-1H-1,3-benzimidazole, C20H15N3O2, (III), has been performed. They are nonplanar structures whose crystal arrangement is governed by Csp 2—H...A (A = NO2, Npy and π) hydrogen bonding. The inherent complexity of the supramolecular arrangements of compounds (I) (Z′ = 2) and (II) (Z′ = 4) into tapes, helices and sheets is the result of the additional participation of π–{\pi}_{{\rm NO}_2}} and n–π* (n = O and Npy; π* = Csp 2 and {\rm N}_{{\rm NO}_2}}) interactions that contribute to the stabilization of the equi-energetic conformations adopted by each of the independent molecules in the asymmetric unit. In contrast, compound (III) (Z′ = 1) is self-paired, probably due to the effect of the steric demand of the methyl group on the crystal packing. Theoretical ab initio calculations confirmed that the presence of the arene ring at the benzimidazole 2-position increases the rotational barrier of the nitrobenzene ring and also supports the electrostatic nature of the orthogonal ONO...Csp 2 and Npy...NO2 interactions.


2017 ◽  
Vol 25 (9) ◽  
pp. 689-694
Author(s):  
Rui Zou ◽  
Qin Zhou ◽  
Qida Liu ◽  
Quanli Li ◽  
Zhiqing Chen ◽  
...  

A hydroxyapatite (HAP)/silk fibroin (SF) bone-like biomaterial was fabricated through a coprecipitation process using stepped temperatures. We evaluated the effect of increasing temperatures on hydroxyapatite crystal arrangement on a silk fibroin surface. We found that the HAP crystal particles self-assembled on the silk fibroin surface. Further we found that with rising temperature the HAP crystal c-axis became progressively more parallel to the long axis of the silk fibroin. This deposition pattern is similar to that seen with HAP and collagen assembly in normal bone. Based on the XRD, SEM, and TEM results, we conclude that higher temperatures promote crystal nucleation resulting in an increase in both HAP crystal size and HAP/SF particle size. These data support the use of HAP/SF bone-like biomaterials for bone replacement and regeneration.


2015 ◽  
Vol 15 (12) ◽  
pp. 5693-5704 ◽  
Author(s):  
Kim Moens ◽  
Nathalie De Clercq ◽  
Stefanie Verstringe ◽  
Koen Dewettinck

Optik ◽  
2015 ◽  
Vol 126 (19) ◽  
pp. 2153-2156 ◽  
Author(s):  
Ameneh Nejati ◽  
Ferdows B. Zarrabi ◽  
Maryam Rahimi ◽  
Zahra Mansouri

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