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2022 ◽  
pp. 1-23
Author(s):  
Zeeshan Ali ◽  
Tahir Mahmood ◽  
Kifayat Ullah ◽  
Ronnason Chinram

The major contribution of this analysis is to analyze the confidence complex q-rung orthopair fuzzy weighted averaging (CCQROFWA) operator, confidence complex q-rung orthopair fuzzy ordered weighted averaging (CCQROFOWA) operator, confidence complex q-rung orthopair fuzzy weighted geometric (CCQROFWG) operator, and confidence complex q-rung orthopair fuzzy ordered weighted geometric (CCQROFOWG) operator and invented their feasible properties and related results. Future more, under the invented operators, we diagnosed the best crystalline solid from the family of crystalline solids with the help of the opinion of different experts in the environment of decision-making strategy. Finally, to demonstrate the feasibility and flexibility of the invented works, we explored the sensitivity analysis and graphically shown of the initiated works.


Author(s):  
C. Yohanna ◽  
A. Kwaji ◽  
R. Atiko

The study was aimed at the in-vitro investigation of the antibacterial activity, antioxidant potential and bioactive compound isolation from ethyl acetate crude fraction of Laggera aurita (L. aurita) Linn. The crude fraction was tested against five gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhi, Proteus mirabilis) and three gram positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis) using macro dilution technique. The antioxidant potentials were evaluated using two different but complementary methods namely ferrous ion chelating activity (FICA) and ferric reducing antioxidant potential (FRAP). Phytocompound isolation was carried out on low pressure open column chromatography. The crude fraction displayed moderate to significant activity against all tested bacteria exhibiting both bacteriostatic and bactericidal effects. The crude fraction showed Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) in the range of 62.50-250 µg/mL and 125-1000 µg/mL respectively. The crude fraction was bactericidal to all tested pathogens except E. coli. The fifty percent effective concentration (EC50) of EDTA standard and the ethyl acetate fraction were obtained as 10.87 μg/mL and 25.77 μg/mL respectively. Similarly the FRAP determinations for ascorbic acid and ethyl acetate fraction yielded 153.63 and 134.40 Fe2+ Equivalent per g of fraction indicating 80.06% and 70.61% FRAP units respectively. The isolated phytocompound coded LAE was obtained as a white crystalline solid with melting point of 136‐138°C and Rf of 0.56 in hexane: ethylacetate (6:4). The isolated compound was identified by spectroscopic data analysis from FT-IR, GC-MS, 1D and 2D NMR and in comparison with literature. The compound was identified as stigmasterol. The observed significant antibacterial and antioxidant properties demonstrated by L. aurita in this study validate its widespread use in traditional medicine. Therefore the study had shown that L. aurita contains bioactive principles and may serve as a source for potential antibacterial and oxidative stress therapeutic agents.


2021 ◽  
Author(s):  
Richard Mandle ◽  
Laurence Abbott ◽  
Luma Fritsch ◽  
Rachel Parker ◽  
Sam Hart ◽  
...  

We report on the characterisation of a number of liquid-crystalline materials featuring cyclic terminal groups, which lead to significant enhancements in the temperature range of the mesomorphic state. Materials with only short terminal chains are able to support lamellar mesophase formation by appending a large terminal cyclic unit at the end of a short methylene spacer. X-ray scattering experiments reveal that the layer spacings of the lamellar smectic phase are significantly larger when a cyclic end-group is present than for equivalent linear unsubstituted materials, but there is no effect on orientational order. Fully atomistic molecular dynamics simulations faithfully reproduce experimental layer spacings and orientational order parameters, and indicate that the cyclic terminal units spontaneously segregate into diffuse sub-layers and thus cause the increased layer spacing. This shape segregation predicted by molecular dynamics simulations is observed in the crystalline solid state by X-ray diffraction.


Author(s):  
Niharika Chauhan

Habitual consumption of raw fruits as well as vegetables can trim down the threat of many diseases. Ginger is consumed globally as a cuisine and herbal medicine. It is rich in pungent phenolic phytochemical substances together called gingerols. 6-Gingerol (1-[4’-hydroxy-3’-methoxyphenyl]-5-hydroxy-3- decanone) is the chief pharmacologically-active moiety of ginger. Molecularly, gingerol is a relative of capsaicin and piperine, the compounds which are alkaloids, though the bioactive pathways are unconnected. It is normally found as pungent yellow oil in the ginger rhizome, but can also form a low-melting crystalline solid. Previous studies have suggested ample of therapeutic activities including anticancer, anti-inflammation and anti-oxidation. 6-Gingerol has been found to possess anticancer activities via its effect on a variety of biological pathways involved in apoptosis, cell cycle regulation, cytotoxic activity and inhibition of angiogenesis. Thus, due to its efficacy and regulation of multiple targets, as well as its safety for human use, 6-gingerol has received considerable interest as a potential therapeutic agent for the prevention and/or treatment of various diseases. Overall, this review encapsulates different therapeutic and pharmacological facets of 6-gingerol along with its possible mechanism of action.


2021 ◽  
Vol 923 (1) ◽  
pp. 90
Author(s):  
Carl Melis ◽  
Johan Olofsson ◽  
Inseok Song ◽  
Paula Sarkis ◽  
Alycia J. Weinberger ◽  
...  

Abstract We present a detailed characterization of the extremely dusty main-sequence star TYC 8830 410 1. This system hosts inner planetary system dust (T dust ≈ 300 K) with a fractional infrared luminosity of ∼1%. Mid-infrared spectroscopy reveals a strong, mildly crystalline solid-state emission feature. TYC 8830 410 1 (spectral type G9 V) has a 49.5″ separation M4-type companion comoving and co-distant with it, and we estimate a system age of ∼600 Myr. TYC 8830 410 1 also experiences “dipper”-like dimming events as detected by the All-Sky Automated Survey for Supernovae, Transiting Exoplanet Survey Satellite, and characterized in more detail with the Las Cumbres Observatory Global Telescope. These recurring eclipses suggest at least one roughly star-sized cloud of dust orbits the star in addition to assorted smaller dust structures. The extreme properties of the material orbiting TYC 8830 410 1 point to dramatic dust-production mechanisms that likely included something similar to the giant impact event thought to have formed the Earth–Moon system, although hundreds of millions of years after such processes are thought to have concluded in the solar system. TYC 8830 410 1 holds promise to deliver significant advances in our understanding of the origin, structure, and evolution of extremely dusty inner planetary systems.


2021 ◽  
Vol 13 (23) ◽  
pp. 13303
Author(s):  
Wenqing Liang ◽  
Qining Xun ◽  
Zhiyong Shu ◽  
Fuming Lu ◽  
Hua Qian

The crystalline solid-air in the liquid hydrogen will cause erosion or friction on the elbow, which is directly related to the safety of liquid hydrogen transportation. The CFD-DPM model was used to study the erosion characteristics of solid-air to liquid hydrogen pipelines. Results show that the outer wall of the cryogenic liquid hydrogen elbow has serious erosion in the range of 60–90°, which is different from the general elbow. The erosion rate is linearly positively correlated with the mass flow of solid-air particles, and the erosion rate has a power function relationship with the liquid hydrogen flow rate. The fitted relationship curve can be used to predict the characteristics and range of the elbow erosion. The structure of the liquid hydrogen elbow also has an important influence on the solid-cavity erosion characteristics. The increase of the radius of curvature is conducive to the reduction of the maximum erosion rate, while the average erosion rate undergoes a process of increasing and then decreasing. The radius of curvature is 60 mm, which is the inflection point of the average erosion rate of the 90° elbow. The research results are expected to provide a theoretical basis for the prevention of liquid hydrogen pipeline erosion.


2021 ◽  
Author(s):  
Bhaskar Chandra Sahoo ◽  
Suprava Sahoo ◽  
Sanghamitra Nayak ◽  
Basudeba Kar

Zingerone (4-(4-Hydroxy-3-methoxyphenyl)-2-butanone) is one of the non-volatile and nontoxic compounds of ginger. It is also called vanillylacetone with a crystalline solid form which is sparingly soluble in water and more soluble in ether. The contribution of this compound in ginger is about 9.25%. The chemical structure is made of a phenolic ring with methoxy group attached to benzene ring. Gingerol can be heated to form zingerone by retroaldol reaction. It has been reported that zingerone has multiple pharmacological activities. It is effective against diarrhoea causing enterotoxigenic bacteria that leads to infant death. It is also used against intestinal gastric, oxidative stress, weak immunity, obesity. During its activity against cancer, it governs the expression of different cell cycle protein and TGF-?1 expression. Antioxidant response is controlled by inducing the activity of ROS neutralising enzymes like superoxide dismutase, catalase and glutathione reductase. It can also reduce various inflammations by restricting the activity of interleukins. This review summarizes the multiple pharmacology activities of zingerone against various important diseases like cancers, tumors, inflammations, oxidative conditions, microbial infections, biofilm formations, thrombosis and other diseases. In addition, the molecular regulation of these pharmacological responses by zingerone is also critically discussed.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
S. Iguchi ◽  
R. Masuda ◽  
S. Seki ◽  
Y. Tokura ◽  
Y. Takahashi

AbstractSpontaneous symmetry breaking in crystalline solid often produces exotic nonreciprocal phenomena. As one such example, the unconventional optical rotation with nonreciprocity, which is termed gyrotropic birefringence, is expected to emerge from the magnetoelectric coupling. However, the fundamental nature of gyrotropic birefringence remains to be examined. Here w`e demonstrate the gyrotropic birefringence enhanced by the dynamical magnetoelectric coupling on the electrically active magnon resonance, i.e. electromagnon, in a multiferroic helimagnet. The helical spin order having both polarity and chirality is found to cause the giant gyrotropic birefringence in addition to the conventional gyrotropy, i.e. natural optical activity. It is demonstrated that the optical rotation of gyrotropic birefringence can be viewed as the nonreciprocal rotation of the optical principal axes, while the crystallographic and magnetic anisotropies are intact. The independent control of the nonreciprocal linear (gyrotropic birefringence) and circular (natural optical activity) birefringence/dichroism paves a way for the optically active devices.


2021 ◽  
Vol 75 (11) ◽  
Author(s):  
Siegfried Kollotzek ◽  
Florent Calvo ◽  
Serge Krasnokutski ◽  
Fabio Zappa ◽  
Paul Scheier ◽  
...  

Abstract Physisorption on planar or curved graphitic surfaces or aromatic rings has been investigated by various research groups, but in these studies, the substrate was usually strictly rigid. Here, we report a combined experimental and theoretical study of helium adsorption on cationic hexaphenylbenzene (HPB), a propeller-shaped molecule. The orientation of its propeller blades is known to be sensitive to the environment, with substantial differences between the molecule in the gas phase and in the crystalline solid. Mass spectra of He$$_{n}$$ n HPB$$^{+}$$ + , synthesized in helium nanodroplets, indicate enhanced stability for ions containing $$n = 2, 4, 14, 28, 42, 44$$ n = 2 , 4 , 14 , 28 , 42 , 44 , or 46 helium atoms. Path-integral molecular dynamics simulations reveal a significant dependence of the dissociation energy on the details of the HPB geometry. Good agreement between the experimental data and calculated dissociation energies is obtained, provided that the symmetry of HPB$$^{+}$$ + is reduced from $$D_{6}$$ D 6 to $$D_{2}$$ D 2 , such a lower symmetry being suggested from quantum chemical calculations as arising upon electron removal. Graphic Abstract


Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3462
Author(s):  
Nurul Asma Razali ◽  
Zuhair Jamain

Liquid crystal is an intermediate phase between the crystalline solid and an isotropic liquid, a very common substance in our daily lives. Two major classes of liquid crystal are lyotropic, where a liquid crystal is dissolved in a specific solvent under a particular concentration and thermotropic, which can be observed under temperature difference. This review aims to understand how a structure of a certain azo compound might influence the liquid crystal properties. A few factors influence the formation of different liquid crystals: the length of the alkyl terminal chain, inter/intra-molecular interaction, presence of spacer, spacer length, polarization effects, odd-even effects, and the presence of an electron-withdrawing group or an electron-donating group. As final observations, we show the compound’s different factors, the other liquid crystal is exhibited, and the structure–property relationship is explained. Liquid crystal technology is an ideal system to be applied to products to maximize their use, especially in the electronic and medical areas.


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