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A large data set of over 30 thousand organic compounds containing carbon, nitrogen, oxygen, fluorine, and hydrogen was collected, and the density of each compound was predicted by 1D descriptors derived from its molecular formula and 2D descriptors derived from its constitutional structural features. The 2D structural features are composed of Benson's groups, corrected groups, and 2D structural features of the whole molecular structures. All the descriptors were extracted by an in-house program in Java with a function to ensure that each atom (or bond) of molecules is represented by Benson's groups once for atom-based (or bond-based) descriptors. Partial least square (PLS) and random forest (RF) methods were used separately to build models to predict the density. Further, the variable selection of descriptors was performed by variable importance of RF. For partial least square, the combination of the models constructed by descriptors based on the atoms and the bonds achieved the best results in this paper: for the cross-validation of the training set, the Pearson correlation coefficient (R) = 0.9270, mean absolute error (MAE) = 0.0270 g·cm−3, and root mean squared error (RMSE) = 0.0426 g·cm−3; for the prediction of the test set, R = 0.9454, MAE = 0.0263 g·cm−3, and RMSE = 0.0375 g·cm−3. [ABSTRACT FROM AUTHOR]

Understanding the molecular structure characteristics of coal at the molecular level is of great significance to realize the rational utilization and efficient conversion of coal. This paper gives insights into the acquisition of characterization parameters of coal molecular microstructure by testing and analyzing the long flame coal from Qinggangping (QGP) Coal Mine through proximate analysis, ultimate analysis, vitrinite reflectance determination, fourier transform infrared Spectroscopy test (FTIR), X-ray photoelectron epectroscopy test (XPS), carbon nuclear magnetic resonance (13C-NMR) and X-ray diffraction (XRD). The results show that benzene rings in the QGP coal are mainly connected in a disubstituted way, accounting for 36.48%. Oxygen atoms mainly exist in the oxygen-containing functional groups such as the ether C–O, C=O and –COO. Aliphatic hydrocarbons in the aliphatic group are mainly of symmetrical -CHx stretching vibration. Hydroxyl groups are mainly composed of OH–OH and OH–O hydrogen bonds, accounting for 29.21% and 21.53%, respectively. Nitrogen atoms exist in the form of C4H5N. The coal molecular is mainly of aromatic carbon structure, where the ratio of bridge aromatic carbon to peripheral carbon is 0.198. There are benzene, naphthalene and anthracene in the coal molecular structure, and the former two chemicals play a dominating role. According to the analysis results, the molecular formula of the QGP coal is finally determined as C205H181O29N3S. On this basis, the two-dimensional and three-dimensional macromolecular models are constructed with the assistance of simulation software. In addition, the 13C-NMR spectra and densities of the constructed molecular models are calculated, which verifies the rationality of the models. The macromolecular structure model of bituminous coal constructed in this study provides a theoretical model basis for the optimal surfactant. [ABSTRACT FROM AUTHOR]

In this paper, two hydrated double salts, whose chemical formulas are K2Mn0.15Co0.85(SO4)2(H2O)6 (KMn/Co) and K2Mn0.16Zn0.84(SO4)2(H2O)6 (KMn/Zn), were crystallized via solvent slow evaporation. The structural, thermal, and vibrational properties were explored and discussed. Furthermore, a study of geometric, electronic, and thermodynamic (entropy, enthalpy, and free energy) parameters was performed based on computational calculations. Single-crystal X-ray diffraction indicated that the compounds belong to the family of mixed Tutton salts with monoclinic symmetry, space group P21/c ( C 2 h 5 ), and occupancy factors of Mn0.15/Co0.85 (KMn/Co) and Mn0.16/Zn0.84 (KMn/Zn). Additionally, the intermolecular contacts and total empties in the unit cells were determined by Hirshfeld surfaces and crystal voids, respectively. The two crystals exhibited thermal stability around 333 K (Mn–Co) and 348 K (Mn–Zn). Above these temperatures, endothermic and exothermic events characteristic of dehydration, crystallization, solid–solid transition, and melting are recorded. Furthermore, KMn/Co and KMn/Zn exhibited significant energy densities, making them promising candidates for thermochemical energy storage systems. An energy band gap of 4.13 eV and 4.49 eV was predicted for KMn/Co and KMn/Zn, respectively. These findings are characteristic of insulating materials with major contributions from p orbitals in the valence and conduction bands. Using group theory and density functional theory (DFT), it was suggested that the two compounds have a total of 183 optical modes in the spectral region from 30 to 3600 cm−1. Furthermore, experimental and calculated Raman and infrared spectra showed a good correlation. Our data suggest that the KMn/Co and KMn/Zn salts present promising thermo-structural results, showing that they can be used in heat-storing thermochemical devices due to their low dehydration temperatures, high dehydration enthalpies, and good energy density. [ABSTRACT FROM AUTHOR]

Among a large number of nitrogen-containing heterocyclic compounds, pyrazole is a privileged scaffold with the molecular formula C3H3N2H. It consists of a five-membered ring with 3-carbon atoms and 2-nitrogen atoms which are present in adjacent positions. The nucleus has attracted synthetic interest due to numerous pharmacological activities. This molecule is used as one of the basic moieties for leads in the area of drug discovery and development and thereby plays a vital role in the field of medicinal chemistry. The present review article highlights the SAR studies of potent compounds of pyrazole and its derivatives (2015–2022) reported as anti-inflammatory, anticancer, antidiabetic, anticonvulsant, antimicrobial, antimycobacterial, antineurodegenerative and antioxidant. Furthermore, a patent application published in this period is also discussed. Google, PubMed, Cochrane, Scopus, ResearchGate, Google Scholar, and Science Direct were primarily used for article search, whereas the databases used for the pyrazole patent were Espacenet, Google Patent, and SciFinder. More than one hundred thirty papers were screened after which inclusion and exclusion criteria were applied to make this review article. We hope the current review article can pave the way for the future drug design and development of pyrazole derivatives as a potential drug candidate. [ABSTRACT FROM AUTHOR]

This paper synthesizes a Ce (III) complex with 1,10-phenanthroline (phen) as the ligand, whose chemical formula is confirmed as Ce(NO3)3(phen)2, and evaluate its inhibition effects on the corrosion of P110 carbon steel in 0.5 M HCl by electrochemical measurements, surface analyses and theoretical calculations. The results show that the Ce(NO3)3(phen)2 complex exhibits high corrosion inhibition efficiencies of ~ 95% at 298 K (25 °C) and ~ 90% at relatively high temperature of 328 K (55 °C), outperforming its cerium salt and ligand of phen. The highest corrosion inhibition efficiency of Ce(NO3)3(phen)2 corresponds to its highest thermodynamics parameters of activation energy (Ea), activation enthalpy (ΔHa) and activation entropy (ΔSa) and the equilibrium constant of adsorption (Kads). Surface analyses further confirm the superior corrosion inhibition performance of Ce(NO3)3(phen)2. Moreover, the X-ray photoelectron spectroscopy analysis indicate that Ce(NO3)3(phen)2 can inhibit corrosion by simultaneously forming adsorption film via its phen ligand and precipitation film via its Ce (III) complex, which could be the reason for its high corrosion inhibition performance at high temperature. DFT calculations and molecular dynamic simulation show a good correlation with the experimental results. [ABSTRACT FROM AUTHOR]

This paper reports synthesis by wet chemical route for neodymium doped lanthanum arsenates nanoparticles with chemical formula NdxLa1−xAsO4 (x = 0.0, 0.05, 0.10 and 0.15) and its characterization. Powder X-ray diffraction (PXRD) confirms monoclinic structure of the prepared nanomaterials. Crystallite size decreases with increasing concentration of Nd3+ ions. PXRD results are further validated by Rietveld refinement with low values of goodness factor (χ2). Morphology has been investigated by high resolution transmission electron microscopy (HRTEM) equipped with selected area electron diffraction (SAED) which shows the crystalline nature of nanomaterials. Various functional groups present have been studied by FTIR spectroscopy. The optical band gap calculated using UV–Vis diffuse reflectance spectroscopy is found to decrease with increasing dopant concentration. The emission spectrum studied by applying photoluminescence (PL) spectroscopy. At 315 nm excitation, the NdxLa1−xAsO4 exhibits a bright red emission with emission peaks in the range of 610–630 nm. Chromaticity plot shows that chromaticity coordinates are located in the red region. The dielectric analysis carried out to study variation of dielectric constant with frequency over range of 1–25 kHz and temperature range of 20–200 °C. The conductivity measurements are carried out and activation energy has been calculated. The variation of electrical modulus with frequency has also been observed. [ABSTRACT FROM AUTHOR]

In this paper we present results for reduced ionization coefficients (α/N, N—gas density) obtained from the breakdown voltage and emission profile measurements in low-pressure dc discharges in two freons: 1,1,1,2-tetrafluoroethane (R134a) with the chemical formula CH2F–CF3 and 2,3,3,3-tetrafluoropropene (HFO1234yf) with the chemical formula CH2=CFCF3. Our results for α/N are determined from the axial emission profiles in low-current Townsend discharge and lay in the intervals of reduced electric fields E/N (E—electric field, N—gas density), from 2.7 to 5.9 kTd for R134a and from 5 to 23 kTd for HFO1234yf. We also provide a comparison of our experimental results with those from the available literature. [ABSTRACT FROM AUTHOR]

In this paper, magnesium substitute cobalt ferrite with chemical formula Co1−xMgxFe2O4 (x = 0.0, 0.25, 0.5, 0.75, 1.0) was prepared by sol–gel method. The prepared ferrite powder was characterized in a series of ways. X-ray diffraction (XRD) shows that the samples have a single-phase cubic spinel structure, and the structural parameters of the samples are different with the ion distribution. Fourier transform infrared spectroscopy (FTIR) can further verify the spinel structure of ferrite and analyze the elastic modulus of the prepared material. Beyond that, the completeness of chemical reactions can be determined by the information of functional groups. A scanning electron microscope (SEM) was used to monitor the morphology of the sample, which also showed that the samples were evenly distributed and agglomerated due to magnetic influence. Energy dispersive spectrometers (EDS) show that the elemental composition of the substance corresponds to a chemical formula and is free of other impurities. Vibrating sample magnetometer (VSM) shows that non-magnetic Mg2+ can replace magnetic Co2+, which changes the interaction intensity and magnetic order between sites, thus changing the magnetic properties of samples, and realizing the magnetic transition from ferromagnetism to superparamagnetism. [ABSTRACT FROM AUTHOR]

In this paper, a reinforcement learning model is proposed that can maximize the predicted binding affinity between a generated molecule and target proteins. The model used to generate molecules in the proposed model was the Stacked Conditional Variation AutoEncoder (Stack-CVAE), which acts as an agent in reinforcement learning so that the resulting chemical formulas have the desired chemical properties and show high binding affinity with specific target proteins. We generated 1000 chemical formulas using the chemical properties of sorafenib and the three target kinases of sorafenib. Then, we confirmed that Stack-CVAE generates more of the valid and unique chemical compounds that have the desired chemical properties and predicted binding affinity better than other generative models. More detailed analysis for 100 of the top scoring molecules show that they are novel ones not found in existing chemical databases. Moreover, they reveal significantly higher predicted binding affinity score for Raf kinases than for other kinases. Furthermore, they are highly druggable and synthesizable. [ABSTRACT FROM AUTHOR]

Phytic acid (PA) is an abundant natural plant component that exhibits a versatility of applications benefited from its chemical structure, standing out its use as food, packing and dental additive due to its antimicrobial properties. The capacity of PA to chelate ions is also well-established and the formation and thermodynamic properties of different metallic complexes has been described. However, research studies of these compounds in terms of chemistry and biological features are still demanded in order to extend the application scope of PA complexes. The main goal of this paper is to deepen in the knowledge of the bioactive metal complexes chemistry and their bactericide activity, to extend their application in biomaterial science, specifically in oral implantology. Thus, this work presents the synthesis and structural assessment of two metallic phytate complexes bearing the bioactive cations Zn2+ and Sr2+ (ZnPhy and SrPhy respectively), along with studies on the synergic biological properties between PA and cations. Metallic phytates were synthesized in the solid-state by hydrothermal reaction leading to pure solid compounds in high yields. Their molecular formulas were C6H12024P6Sr4·5H2O and C6H12024P6Zn6·6H2O, as determined by ICP and HRES-TGA. The metal coordination bond of the solid complexes was further analysed by EDS, Raman, ATR-FTIR and solid 13C and 31P-NMR spectroscopies. Likewise, we evaluated the in vitro ability of the phytate compounds for inhibiting biofilm production of Streptococcus mutans cultures. Results indicate that all compounds significantly reduced biofilm formation (PA < SrPhy < ZnPhy), and ZnPhy even showed remarkable differences with respect to PA and SrPhy. Analysis of antimicrobial properties shows the first clues of the possible synergic effects created between PA and the corresponding cation in different cell metabolic processes. In overall, findings of this work can contribute to expand the applications of these bioactive metallic complexes in the biotechnological and biomedical fields, and they can be considered for the fabrication of anti-plaque coating systems in the dentistry field. [ABSTRACT FROM AUTHOR]

A low-cost, a high-yielding of vanadium oxide nanobelts 2 was simply synthesized by hydrothermal treatment of our (NH4)2V3O8, 1, with deionized water at 200 °C for 3 days. The SEM observations show that ribbon-like nanobelts are about 150- 300 nm wide and thousands of nanometers long. The XRD pattern reveals a set of the paper form reflections, characteristic of (001) reflections for layered phases. Based on FT-IR results and the EDX spectra, the chemical formula of the as-obtained ribbonlike nanobelts could be described as VxOy.nH2O with a mixed valence V(V) and V(IV). [ABSTRACT FROM AUTHOR]

CoMoO4 material has great advantages in the application of supercapacitors, but the low conductivity and reactivity of CoMoO4 limit its capacity and energy density severely, resulting in a certain gap between the actual value and the theoretical value of specific capacitance. As an electrode material, the performance of CoMoO4 electrode material with spinel structure is directly related to the microstructure of the material. In this paper, CoMoO4 material grown in situ on nickel foam was synthesized by hydrothermal method. Through electrochemical performance tests, the best electrochemical performance belong to the materials using ammonium molybdate and cobalt nitrate as raw materials, synthesized at hydrothermal temperature of 140 °C for 10 h, and calcined at 250 °C for 1 h. The discharge capacity of the material is up to 11.112 F/cm2 at the current density of 3 mA/cm2. The XRD characterization shows that the material has good crystallinity, and it belongs to the orthorhombic structure. The SEM characterization shows that the synthesized material is in cuboid rod structure with loose folds on the periphery. According to EDS analysis, the atomic proportion of each element is close to that in the molecular formula. The positions of absorption peaks in the infrared spectrum are consistent with that of CoMoO4 material. [ABSTRACT FROM AUTHOR]

Extraction of chemical formulas from images was not in the top priority of Computer Vision tasks for a while. The complexity both on the input and prediction sides has made this task challenging for the conventional Artificial Intelligence and Machine Learning problems. A binary input image which might seem trivial for convolutional analysis was not easy to classify, since the provided sample was not representative of the given molecule: to describe the same formula, a variety of graphical representations which do not resemble each other can be used. Considering the variety of molecules, the problem shifted from classification to that of formula generation, which makes Natural Language Processing (NLP) a good candidate for an effective solution. This paper describes the evolution of approaches from rule-based structure analyses to complex statistical models, and compares the efficiency of models and methodologies used in the recent years. Although the latest achievements deliver ideal results on particular datasets, the authors mention possible problems for various scenarios and provide suggestions for further development. [ABSTRACT FROM AUTHOR]

Chemical graph theory is a field of mathematics that studies ramifications of chemical network interactions. Using the concept of star graphs, several investigators have looked into the solutions to certain boundary value problems. Their choice to utilize star graphs was based on including a common point connected to other nodes. Our aim is to expand the range of the method by incorporating the graph of hexasilinane compound, which has a chemical formula H 12 Si 6 . In this paper, we examine the existence of solutions to fractional boundary value problems on such graphs, where the fractional derivative is in the Caputo sense. Finally, we include an example to support our significant findings. [ABSTRACT FROM AUTHOR]

The only way to dispose of municipal solid waste (MSW) in Oman is in engineered landfills without pre-treatment. An effective waste management system requires a reliable database of solid waste composition, properties, and energy content. Although investigating waste in landfills in Muscat Governorate is challenging and complex, it is essential. In this study, MSW from Muscat Governorate landfills is examined. The MSW samples were collected et al. Amerat and Barka landfills in 2020 in order to determine some of the importance of their physiochemical properties and the ratio of materials (food, plastic, and paper). It was found that approximately 50% of the weight of the disposed waste was recyclable. There were high levels of biodegradable organic material in MSW. In terms of moisture content, MSW ranged from 21.5 to 43.3%. Both the volatility and loss of ignition of MSW were high. It was found that the total oxide ratios ranged from 12.4 to 44.06%. The elemental analysis of Muscat MSW resulted in six chemical formulas for MSW with and without sulfur. Silica is the most influential oxide, followed by calcium oxide. The findings of this study indicate that almost half of Muscat's municipal solid waste can be recycled. Solid waste can be recycled to create renewable materials that can replace oil as a by-product of the recycling industry. Additionally, Muscat MSW has a high moisture content, which enables it to be composted and biodegraded. Moreover, waste-to-energy technologies are feasible due to their high-energy content. [ABSTRACT FROM AUTHOR]

Multiferroic nanocomposites with the chemical formula, (x).Bi0.95Mn0.05FeO3-(1-x). Ni0.5Zn0.5Fe2O4, (where x = 0.2, 0.4, 0.5, 0.6, and 0.8) have been synthesized using sol–gel autocombustion and conventional solid-state reaction methods. Resistivity and impedance measurements were taken in order to understand the properties of the conductivity of the samples. Multiple hopping mechanisms were evident from the studies of impedance analysis with the traces of different trends from Nyquist plots. Magnetoelectric (ME) coupling coefficient (αME) studies were taken in order to understand the possible coupling in the synthesized composites. The composites exhibit different values for αME, and it was observed to be varying systematically in accordance with the mixing ratios of the individual constituent phases. Interestingly, the composite with equal ratio (x = 0.5) of both the individual phases shows enhanced value for αME along longitudinal and transverse modes. The observed typical values of αME along the longitudinal and transverse modes are 28.083 mV/cm. Oe and 27.098 mV/cm. Oe, respectively. The possible reasons for the improvement in the coupling factor are well discussed and are attributed to the charge balance along with the structural inhomogeneities prevailed during the formation of the composite. In addition, the observed difference in magnitudes of αME along the longitudinal and transverse modes are also examined and presented in this paper. Improved structural, resistive, impedance and magnetoelectric coupling studies suggest that these composites are well suitable for the applications of spintronic-based devices. [ABSTRACT FROM AUTHOR]

In this paper, the layered aluminosilicate Al-magadiite (Al-mag) material and the layered/microporous Al-magadiite/ZSM-5 (Al-mag/Z) composite were successfully prepared with the same molar composition by using a hydrothermal way. By adding the organic structuring agent to this composition, the MFI-type zeolite formation was favorable, which the process led to the Al-mag/Z composite. For this, several techniques were used to identify the samples such as X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), thermogravimetric analysis (TG) and (DTA), UV–Visible diffuse reflectance (UV–Visible DR), infrared spectra (FTIR) and scanning electron microscope (SEM). The well crystallized Al–mg sample was obtained under the conditions of 150 °C and 168 h without any templating agent. The EDX analysis revealed the presence of aluminum into the lamellar structure, which their chemical formula was well defined (Na1.57 Si13.54 Al0.28, 7.51H2O). Moreover, the typical cauliflower morphology with the open aggregations of plaques was identified with their particles size of about 11 μm. By adding the Triethanolamine organic agent a mixture of two phases of materials was obtained, which gives the Al-mag/Z layered/microporous aluminosilicates composite. The morphology of this composite shows elongated hexagonal crystals with different size less than 10 μm. In Addition, the presence of aluminum can probably lead to a modification of the surface acidity of the composite, which can gives the advantage of evaluating these materials in reaction models for high Brønsted acidity. [ABSTRACT FROM AUTHOR]

Silica (chemical formula SiO2) is a promising, more environmentally friendly alternative to carbon black (CB) used in the rubber industry as a filler. Although silica is already used in rubber products, it is not used as extensively as CB because the polar surface of silica cannot interact well with the apolar polymer molecules of the most frequently used rubbers. To solve this problem, experts have tried different grafting methods and several coupling agents for a stronger silica-elastomer connection. In this article, we used bis[3-(triethoxysilyl)propyl] tetrasulfide (TESPT) and polyethylene glycol (PEG) combined to improve the connection between the surface of silica and the apolar styrene-butadiene rubber (SBR) matrix. We examined mechanical and structural properties and found that adding 3 phr PEG and 4.5 phr TESPT to SBR is optimal for 60 phr silica content. This ratio of additives resulted in a 48% improvement in tensile strength. The positive effect of the coupling agents shows up in abrasion mass loss and tear strength as well. [ABSTRACT FROM AUTHOR]

Background: Plant extracts have attracted significant interest among researchers due to their potential bioactivity and crucial contribution to the production of pharmaceutical compounds. In this study, the primary objective was to extract, analyze and characterize the bioactive compounds found in the methanol root extract of Datura fastuosa (D. fastuosa). This was achieved using various analytical techniques such as gas chromatography/mass spectrometry (GC–MS), ultra-violet visible spectrophotometry, Fourier-transform infrared (FT-IR), nuclear magnetic radiation spectrometry (NMR) and DPPH free radical scavenging activity assay. Results: GC–MS analysis of the methanol root crude extract identified 49 compounds. Three compounds were isolated via column chromatography; one was pure, with a sharp melting point and clean IR spectrum, while the other two showed broad melting points and IR interferences. Comprehensive investigation of the pure extract revealed a UV profile with two distinct bands (300–800 nm) and confirmed functional groups (alcohol, alkanes, alkenes, carbonyl, methylene, and methyl) through FT-IR analysis. The 1HNMR (proton nuclear magnetic resonance spectroscopy) signal confirmed the presence of forty-nine non-equivalent protons, 13CNMR (Carbon-13 nuclear magnetic resonance spectroscopy) signal confirmed the presence of 32 non-equivalent carbons and DEPT-135 (distortionless enhancement by polarization transfer-135) signal confirmed the presence of 24 carbons (17 for odd and 7 for even) which are protons containing carbons in the compound. Combining the above mentioned analyses with data obtained from the GC/MS analysis of National Institute of Standards and Technology (NIST) library, the isolated pure compound exhibited a structural similarity to 1-(7-(3-hydroxyphenyl)-1,1,4a,5,6,9,10a,10b-octamethyl-1,2,3,4,4a,4b,6a,7,8,9,10,10a,10b,11,12,12a-hexadecahydrochrysen-2-yl)propan-1-one, with a chemical formula of C35H50O2. Conclusions: The presence of various notable compounds, including phenolics, flavonoids, alkaloids, steroids etc., within the methanol root extract of D. fastuosa signifies its pharmacological potential. The methanol crude extract demonstrated antioxidant potential compared to standard ascorbic acid, exhibiting DPPH scavenging activity. Previous research has demonstrated the bioactivity of some of these compounds, further elucidating the plant's medicinal properties. These findings not only suggest opportunities for developing synthetic drugs but also underscore its direct therapeutic potential in addressing diverse ailments. [ABSTRACT FROM AUTHOR]

Microorganisms consume and transform dissolved organic matter (DOM) into various forms. However, it remains unclear whether the ecological patterns and drivers of DOM chemodiversity are analogous to those of microbial communities. Here, a large-scale investigation is conducted along the Chinese coasts to resolve the intrinsic linkages among the complex intertidal DOM pools, microbial communities and environmental heterogeneity. The abundance of DOM molecular formulae best fits log-normal distribution and follows Taylor's Law. Distance-decay relationships are observed for labile molecular formulae, while latitudinal diversity gradients are noted for recalcitrant molecular formulae. Latitudinal patterns are also observed for DOM molecular features. Negative cohesion, bacterial diversity, and molecular traits are the main drivers of DOM chemodiversity. Stochasticity analyses demonstrate that determinism dominantly shapes the DOM compositional variations. This study unveils the intrinsic mechanisms underlying the intertidal DOM chemodiversity and microbial communities from ecological perspectives, deepening our understanding of microbially driven chemical ecology. Intertidal DOM follows similar ecological patterns and underlying mechanisms to microbes, suggesting that there may exist universal ecological models explaining the patterns of both living and non-living biological entities in the Earth's biosphere. [ABSTRACT FROM AUTHOR]

Extracts were filtered using Whatman® No. 1 filter paper and concentrated using a rotary evaporator at 40°C and 50°C for the ethyl acetate and methanol extracts, respectively. Compound B 2 b was isolated as a whitish-yellowish noncrystalline solid from the ethyl acetate extract I . i It was obtained from elution with the solvent mixture hexane-ethyl acetate (8:2). This led to the isolation of compounds B 1 b (from the methanol extract) and B 2 b (from the ethyl acetate extract). [Extracted from the article]

The paper considers directions for the development of waste-free, large-scale industrial technologies by setting up new technological routs, including wide use of electrical technologies of a new generation and excluding formation of any industrial waste as a matter of principle. The electrical technologies of a new generation are technologies based on the use of generators and flows of technological plasmas in chemical and metallurgical industries, electromagnetic fields of various frequency ranges for the synthesis and processing of metal and ceramic materials, and technological lasers for, for instance, separation of isotopes and for making micro articles for nanotechnology and micrometallurgy applications. All these technologies have become theoretically and technically feasible in combination with purification technologies for liquid and gaseous raw material preparation for the nuclear fuel cycle (NFC), specifically, ion-exchange sorption on synthetic organic ion-exchange resins, fluid extraction, rectification, or sorption on granular fluoride sorbents, which all provide a tool for attaining any level of purification of raw materials. In many processes discussed in the paper, extraction, sorption and rectification can be directly incorporated in electrical technologies, i.e. this means combined technologies for the synthesis, separation, and purification of the products, such as plasma rectification, plasma sorption, etc. The paper considers a series of such scientifically and technically advanced but still uncommercialized electrical technologies which should form the basis for new environmentally friendly, waste-free industries of a new technological structure. As examples, we focus on several plasma, electromagnetic, and laser technologies, operating on raw materials refined by the above-mentioned purification technologies, including the new technology for the purification of gaseous industrial emissions. These waste-free electrical technologies for the production and processing of inorganic materials were developed for the nuclear industry in the USSR. These are mostly physical technologies insensitive to the chemical formula of the produced or processed materials, and, therefore, they can be used without any problems in other branches of industry. [ABSTRACT FROM AUTHOR]

We report here: (a) formulas/procedures for calculating the similarity of molecules, considering their chemical structure, size, shape and hydrophilicity (b) a procedure for clusterization of the sets of molecules, according to similarity (c) formulas/procedures for calculating the diversity of molecules in clusterized sets as well as similarity of clusterized sets, based on Shannon Entropy formalism The paper analyses the influence of the diversity of molecules and similarity of calibration/prediction sets on the quality of prediction for prediction set molecules. The calculated influence of certain molecular feature (chemical structure, size, shape and hydrophilicity) on toxicity depends on the structure of the database, specifically the number of molecules and diversity of molecules having analyzed molecular feature. A QSAR analysis of 49 phenol derivatives revealed the effect of the diversity of molecules in sets and of the similarity of sets on the quality of prediction for prediction set molecules: (a) a direct correlation with the similarity of sets, regardless of analyzed molecular feature (b) an inverse correlation with the diversity of molecules in the calibration set, from the point of view of chemical structure, size and shape (c) a direct correlation with the diversity of molecules in calibration set, from the point of view of hydrophilicity (d) a direct correlation with the diversity of molecules in prediction set, regardless of analyzed feature. [ABSTRACT FROM AUTHOR]

Chemical structures are being modeled by formulas which in turn may be viewed as graphs. They have to be represented pictorially in two (constitutional formulas) or three dimensions (stereochemical formulas). How to present the latter formulas is the topic of the present paper. First, however, a discussion of isomerism is necessary. Then, for quantitative structure-activity relationships (QSAR) one has to find a correspondence between chemical formulas (or the shape of chemical compounds) and numerical molecular descriptors (also called topological indices). The various types of conventions for translating three-dimensional objects into two-dimensional representations are presented and discussed. It is hoped that stereo-drawings and colored images will facilitate the task of molecular modelers in search for new medicinal drugs. The ultimate goal, the production of holograms for chemical structures, needs the development of specialized software. [ABSTRACT FROM AUTHOR]

In2S3 is one of the attractive compounds taking remarkable interest in optoelectronic device applications. The present study reports the structural and optical characteristics of thermally evaporated β-In2S3 thin films. The crystalline structure of the thin films was found as cubic taking into account the observed diffraction peaks in the X-ray diffraction pattern. The atomic compositional ratio of constituent elements was obtained as consistent with chemical formula of In2S3. Three peaks around 275, 309 and 369 cm−1 were observed in the Raman spectrum. Temperature-tuned bandgap energy characteristics of the In2S3 thin films were revealed from the investigation of transmittance spectra obtained at various temperatures between 10 and 300 K. The analyses of the transmittance spectra indicated that direct bandgap energy of the In2S3 thin films decreases from 2.40 eV (at 10 K) to 2.37 eV (at 300 K) with the increase of measurement temperature. The bandgap energy vs. temperature relation was investigated by means of Varshni optical model. The fitting of the experimental data under the light of theoretical expression revealed the absolute zero bandgap energy, the rate of change of bandgap energy and Debye temperature. [ABSTRACT FROM AUTHOR]

The structure of the crystals of Li(UO2)2(C5H6O4)2F‧6H2O (I), NaUO2(C5H6O4)F‧4H2O (II), and Sr(UO2)2(C5H6O4)2F2‧8H2O (III) was studied by X-ray diffraction analysis for the first time. The uranium-containing structural units in crystals of I are 1D complexes [UO2(C5H6O4)F0.5(H2O)]0.5– with the crystal chemical formula AQ02M20.5M1, where A = UO22+, Q02 = C5H6O42–, M2 = F–, M1 = H2O, and in II and III, 1D complexes of the same composition and structure [UO2(C5H6O4)F]– with the crystal chemical formula AQ02M2. In all compounds, the U(VI) atoms implement hexagonal-bipyramidal coordination, forming coordination polyhedra UO2FO5 (I) and UO2F2O4 (II and III). It was found that the uranyl fluoroglutarate {UJUBEG}, for which the composition [UO2(С5H6O4)F]‧2H2O contradicting the of electroneutrality principle was previously erroneously indicated, should be considered as (Н3O)[UO2(С5H6O4)F]‧H2O. [ABSTRACT FROM AUTHOR]

The article presents instructions for authors who wish to submit papers in the "Journal of Analytical Chemistry." It includes manuscript submission, length of original papers, reviews and short communications or letters to the editor, main heading, use of SI units of measure, mathematical notations and chemical formulas, figures and photographs, tables, references, citations and list of references.

In this work, we introduce a 2D materials family with chemical formula MX2 (M={As, Sb, Bi} and X={S, Se, Te}) having a rectangular 2D lattice. This materials family has been predicted by systematic ab-initio structure search calculations in two dimensions. Using density-functional theory and many-body perturbation theory, we study the structural, vibrational, electronic, optical, and excitonic properties of the predicted MX2 family. Our calculations reveal that the predicted SbX2 and BiX2 monolayers are stable while the AsX2 layers exhibit an in-plane ferroelectric instability. All materials display strong excitonic effects and good optical absorption within the infrared-to-visible range. Hence, these monolayers can harvest solar energy and serve in optoelectronics applications. Furthermore, our results indicate that exfoliation of the predicted MX2 monolayers from their bulk counterparts is experimentally viable. [ABSTRACT FROM AUTHOR]

This article explores the development of a self-emulsifying drug delivery system (SEDDS) to improve the solubility of the anticonvulsant drug Galodif in water. Galodif is currently limited in its therapeutic use due to its poor solubility. The study found that the SEDDS formulations significantly increased the solubility of Galodif in water compared to its tablet form. The use of SEDDS offers advantages such as increased bioavailability, faster onset of action, lower dosage, and reduced side effects. The ingredients used in the SEDDS are readily available, safe, and approved for use in pharmaceutical formulations. [Extracted from the article]

Background: Identifying the molecular formula and fragmentation reactions of an unknown compound from its mass spectrum is crucial in areas such as natural product chemistry and metabolomics. We propose a method for identifying the correct candidate formula of an unidentified natural product from its mass spectrum. The method involves scoring the plausibility of parent candidate formulae based on a parent subformula graph (PSG), and two possible metrics relating to the number of edges in the PSG. This method is applicable to both electron-impact mass spectrometry (EI-MS) and tandem mass spectrometry (MS/MS) data. Additionally, this work introduces the two-dimensional fragmentation plot (2DFP) for visualizing PSGs. Results: Our results suggest that incorporating information regarding the edges of the PSG results in enhanced performance in correctly identifying parent formulae, in comparison to the more well-accepted "MS/MS score", on the 2016 Computational Assessment of Small Molecule Identification (CASMI 2016) data set (76.3 vs 58.9% correct formula identification) and the Research Centre for Toxic Compounds in the Environment (RECETOX) data set (66.2% vs 59.4% correct formula identification). In the extension of our method to identify the correct candidate formula from complex EI-MS data of semiochemicals, our method again performed better (correct formula appearing in the top 4 candidates in 20/23 vs 7/23 cases) than the MS/MS score, and enables the rapid identification of both the correct parent ion mass and the correct parent formula with minimal expert intervention. Conclusion: Our method reliably identifies the correct parent formula even when the mass information is ambiguous. Furthermore, should parent formula identification be successful, the majority of associated fragment formulae can also be correctly identified. Our method can also identify the parent ion and its associated fragments in EI-MS spectra where the identity of the parent ion is unclear due to low quantities and overlapping compounds. Finally, our method does not inherently require empirical fitting of parameters or statistical learning, meaning it is easy to implement and extend upon. Scientific contribution: Developed, implemented and tested new metrics for assessing plausibility of candidate molecular formulae obtained from HR-MS data. [ABSTRACT FROM AUTHOR]

The series expansion formulae in terms of complete orthonormal sets of Ψ α-exponential type orbitals introduced by the author are derived for the two-center charge densities of integer and noninteger n generalized exponential functions. The expansion coefficients arising in these relations are the multicenter overlap integrals of three Ψ α-functions. The charge density expansion formulae obtained are utilized for the evaluation of multicenter multielectron integrals appearing in the Hartree–Fock–Roothaan and explicitly correlated theories when the generalized exponential type orbitals are employed as basis functions. [ABSTRACT FROM AUTHOR]

This paper suggests that the cases made for atoms and the aether in nineteenth-century physical science were analogous, with the implication that the case for the atom was less than compelling, since there is no aether. It is argued that atoms did not play a productive role in nineteenth-century chemistry any more than the aether did in physics. Atoms and molecules did eventually find an indispensable home in chemistry but by the time that they did so they were different kinds of entities to those figuring in the speculations of those natural philosophers who were atomists. Advances in nineteenth-century chemistry were a precondition for rather than the result of the productive introduction of atoms into chemistry. [ABSTRACT FROM AUTHOR]

This paper presents an original method of synthesis of mixed tantalum and niobium carbides from an oxalic precursor elaborated from the tantalite mineral (Fe,Mn)(Ta1− xNb x)2O6. The process of elaboration consists initially in melting the ore with potassium pyrosulphate, then performing a lixiviation with a concentrated hydrochloric acid solution. During the latter reaction, iron and manganese oxides are converted into water-soluble chlorides while the fused mass containing potassium, niobium and tantalum is not dissolved. Traces of chlorides are eliminated by filtration with boiling aqueous solution. Then, the solid is dissolved slowly in hot concentrated sulphuric acid solution. Adding ammonium hydroxide up to a pH of 8 completes the precipitation of niobium and tantalum hydroxides. The precipitate (Ta1− xNb x)(OH)5 is washed and submitted to a reaction of complexation with oxalate ions in an aqueous environment. This reaction involves the formation of a water-soluble oxalic complex containing tantalum and niobium. The excess of water is eliminated by evaporation at 333 K. The tantalum and niobium carbides are obtained by submitting the oxalic complex of chemical formula (NH4)3(Ta1− xNb x)O(C2O4)3· nH2O to a gas-solid reaction in a methane-hydrogen atmosphere at 1273 K. The oxalic precursor and their resultant mixed carbides are characterized by atomic absorption and Infra-Red spectroscopies, thermogravimetric-differential thermal analysis coupled, laser granulometry, X-ray diffraction and transmission electronic microscopy. [ABSTRACT FROM AUTHOR]

Caffeic acid-O-methyltransferase (COMT), an important enzyme governing the process of lignification in plants, functions at the level of caffeic acid methylation along with 3-O-methylation of monolignol precursors. The present investigation was carried out to decipher the role of COMT in tall fescue lignification and to clone and characterize the COMT gene. The study on COMT activity variation at different growth stages of tall fescue exhibited a significant increase in activity over all the growth stages of tall fescue. A significant relative increase of 47.8% was observed from the first vegetative to reproductive stage. COMT activity exhibited a strong positive correlation with lignin content suggesting it to be an important enzyme of tall fescue lignification. Amplification and sequencing of tall fescue COMT gene resulted in an amplicon of size 1662 (Accession No.-MW442832) and an ORF of 346 amino acids. The deduced protein was hydrophobic, thermally stable and acidic with molecular formula C1679H2623N445O482S20, molecular mass 37.4 kDa and theoretical pI of 6.12. The protein possesses a conserved dimerization domain with a highly conserved SAM binding site. The COMT protein was found to be a homo-dimer with 1 catalytic SAH/SAM ligand per monomer interacting with 14 amino acid residues within 4 Å region. [ABSTRACT FROM AUTHOR]

Luminescent Tb(III) complexes with organic ligands have shown great potential for use in optoelectronic devices due to their strong luminescence, long emission lifetimes, and narrow emission bands. In this study, we report the synthesis, characterization, and photophysical properties of a series of Tb(III) complexes with the organic ligand 6-fluoro-3-formylchromone (FFC) and heterocyclic neutral auxiliary ligands. The complex was characterized using UV–visible spectroscopy (UV–Vis), elemental analysis, Fourier-transform infrared spectroscopy (FTIR), thermal studies, mass spectrometry, powder x-ray diffraction studies (PXRD), and photoluminescence (PL) spectroscopy. The results indicate that the complex has a high quantum yield (ϕTb = 56.89%), longer lifetime period (τobs = 0.892 ms), intrinsic quantum yield (ηTb = 29.73%), and radiative rate and green luminescence with a radiative decay rate of (KRad) 6.36 × 102 s−1. The UV–vis absorption spectra showed that the complex has strong absorption in the UV region, and the FTIR spectra confirmed the formation of the complex. The thermal studies revealed that the complex is stable up to 180°C, and the mass spectrometry and elemental analysis confirmed the molecular formula of the complex. PXRD study showed that the complex has a crystalline structure with a particle size in the nanometer range. The PL spectroscopy showed that the complex has a high luminescence intensity and a long emission lifetime. Overall, the results suggest that the Tb(III) complex with FFC is a promising candidate for use in optoelectronic devices. [ABSTRACT FROM AUTHOR]

CS/PVP blend embedded by Sr-hexaferrite nanoparticles as a novel composite material to improve the optical and magnetic properties of composite samples. This work aimed to study and compare the functional and physical properties of CS/PVP film after and before adding SrFe12O19 with different weight percentages to form nanocomposite film with chemical formula CS/PVP/x Wt% SrFe12O19; x = 1, 3, 5 and 7. SrFe12O19 was prepared successfully by using citrate auto-combustion methods, then added to CS/PVP blend with different weight percentages. XRD shows the formation of Sr-hexaferrite in a single phase with an average crystallite size 44 nm. The semi-crystalline nature of CS/PVP film decreases with the addition of Sr-hexaferrite. FTIR displays the interaction between CS/PVP and SrFe12O19 by changing the intensity and broadening the OH band. HRTEM images show that SrFe12O19 has a rod structure and has average particle size ranging from 50 to 100 nm. The coercivity value increased by increasing the weight% of nanofiller as it increased from 421 Oe for SrFe12O19 to 4502.6 and 4488.2 Oe for x = 3 wt% and 7 wt% for SrFe12O19. The transition between the top of the valance band and the bottom of the conduction band in CS/PVP/ x Wt % SrFe12O19; x = 1, 3, 5, 7 system occurred through the indirect transition. [ABSTRACT FROM AUTHOR]

A new Ag(I) boron imidazolate framework with the chemical formula of {Ag[BH(im)3]}n (1, BH(im)3− = tri(imidazolyl)borate) has been synthesized by the self-assembly of Ag(I) and tridentate boron imidazolate ligand. This compound shows intense luminescence and outstanding photocatalytic activity for the Rhodamine B degradation with an irradiation of ultraviolet. Moreover, the compound's therapeutic effects on neonatal pneumonia were explored and the corresponding mechanism was tested in meantime. The enzyme linked immunosorbent assay detection was firstly conducted to measure the content of inflammatory cytokines released into the bronchoalveolar lavage fluid. Then, the activation of JNK/MAPK signaling pathway activation in the alveolar epithelial cells was measured with the real-time reverse transcription-polymerase chain reaction. Finally, the cytotoxicity of the complex was determined with Cell Counting Kit (CCK-8) assay. [ABSTRACT FROM AUTHOR]

Coal fire combustion has been known for a long time to be a complicated physical and chemical process, and finding hidden coal fires has always been a challenge. With the arrival of an advanced quantum detection method, such fires can be accurately identified. Before applying the method to detect hidden coal fires, researchers must develop a better understanding of the transport properties of heat carriers in coal. An examination of a lignite sample taken from a typical coal fire region (Tunbao, Xinjiang, China) was conducted using experimental and computational methods. The molecular structure of Tunbao coal was clarified using methods such as 13C-NMR, XPS, and elemental analysis. A model of Tunbao coal's molecular structure was generated, and its chemical formula was C311H209N3O68. Moreover, ab initio molecular dynamics was used to compute the heat carriers in coal molecules. As revealed by calculations, this coal is a semiconductor with metallic characteristics and is capable of transporting electrons. Naphthalene and pyrrole contribute to this metallicity, and coals with larger amounts of naphthalene and pyrrole may have stronger electrical conductivity. In accordance with the AIMD results, when the temperature rose, the electron transport of coal molecules became more frequent and powerful, resulting in increased electrical conductivity. [ABSTRACT FROM AUTHOR]

The structural and electrical characteristics of the glassy system with the chemical formula (18.75Li2O–18.75Na2O–25V2S5–37.5P2S5 mol%) and its nano-crystallized glass–ceramics have been investigated. The glass sample was prepared via the conventional melt-quenching technique. The corresponding nano-crystallized glass–ceramics were prepared via a heat treatment (HT) procedure at 405 °C for diverse times in the air. The effect of HT time on nanostructure and the dc conductivity for the nano-crystallized glass–ceramics were investigated. X-ray diffraction (XRD) spectra and field emission scanning electron microscopy (FESEM) images confirmed the amorphous nature of the as-synthesized glass and the growth of nano-crystals after heat treatment within the glassy matrix. The nano-crystallized glass–ceramics exhibited considerably higher conductivity and lower activation energy than the initial glass. Furthermore, the dc conductivity was improved by nearly 57 times in the nano-crystallized glass–ceramic samples as compared with the initial glass. The activation energy was improved by utilizing the HT process and was found to be 0.535 eV for the as-prepared glass and between 0.272 and 0.462 eV for the corresponding nano-crystallized glass–ceramics. The dc conductivity increased with decreasing crystalline size in the case of nano-crystallized glass–ceramics, which may be accredited to the reduction in grain boundary scattering brought on by the smaller particle size. The conduction mechanism was emphasized to follow the non-adiabatic small polaron hopping (SPH). [ABSTRACT FROM AUTHOR]

Two coordination polymers (CPs) on the basis of Co(II) have been prepared with or without a nitrogen-donor ligand bipyridine under the conditions of solvothermal, with the chemical formula of {[Co3(IDPA)3(DMA)(H2O)2]·(H2O)(DMA)}n (1, where DMA is N,N-dimethylacetamide, bpy is bipyridine, and H2IDPA is 5-(1-oxoisoindolin-2-yl) isophthalic acid) and [Co(IDPA)(4,4′-bpy)1/2]n (2). Furthermore, the treatment effect of compounds on postpartum depression was assessed and the corresponding mechanism was also investigated. The analysis of enzyme linked immunosorbent assay was applied for testing the progesterone and 5-hydroxytryptamine (5-HT) content in the brain after indicated compound treatment. After that the progesterone and 5-HT relative expression was assessed with the analysis of real-time reverse transcription-polymerase chain reaction. The experimental results show that CP 1 was much powerful than 2 on attenuating the contents of progesterone and 5-HT exist in brain. Besides this, the progesterone and 5-HT receptor relative expression on neurons was also markedly attenuated by CP 1, instead of 2. [ABSTRACT FROM AUTHOR]

Two uranyl succinate polymers, NH4[UO2(Suc)(HSuc)]∙H2O (I) and [UO2(Suc)(H2O)2] (II), where Suc = succinate ion (), were synthesized and studied by X-ray diffraction, IR spectroscopy, and thermography (CCDC nos. 2202634 and 2202635, respectively). The main structural units in the crystals of I are infinite zigzag chains [UO2(Suc)(HSuc)]–, corresponding to the AQ02B01 crystal chemical formula (A = Q02 = B01 = ). It was established that in structure II, the electrically neutral [UO2(Suc)(H2O)2] chains correspond to the crystal chemical formula (A = Q02 = M1 = H2O). The intermolecular interactions in structures I and II were analyzed using the method of molecular Voronoi–Dirichlet polyhedra. [ABSTRACT FROM AUTHOR]

Metabolomics experiments generate highly complex datasets, which are time and work-intensive, sometimes even error-prone if inspected manually. Therefore, new methods for automated, fast, reproducible, and accurate data processing and dereplication are required. Here, we present UmetaFlow, a computational workflow for untargeted metabolomics that combines algorithms for data pre-processing, spectral matching, molecular formula and structural predictions, and an integration to the GNPS workflows Feature-Based Molecular Networking and Ion Identity Molecular Networking for downstream analysis. UmetaFlow is implemented as a Snakemake workflow, making it easy to use, scalable, and reproducible. For more interactive computing, visualization, as well as development, the workflow is also implemented in Jupyter notebooks using the Python programming language and a set of Python bindings to the OpenMS algorithms (pyOpenMS). Finally, UmetaFlow is also offered as a web-based Graphical User Interface for parameter optimization and processing of smaller-sized datasets. UmetaFlow was validated with in-house LC–MS/MS datasets of actinomycetes producing known secondary metabolites, as well as commercial standards, and it detected all expected features and accurately annotated 76% of the molecular formulas and 65% of the structures. As a more generic validation, the publicly available MTBLS733 and MTBLS736 datasets were used for benchmarking, and UmetaFlow detected more than 90% of all ground truth features and performed exceptionally well in quantification and discriminating marker selection. We anticipate that UmetaFlow will provide a useful platform for the interpretation of large metabolomics datasets. [ABSTRACT FROM AUTHOR]

Background: The Chemistry Development Kit (CDK) is a widely used open source cheminformatics toolkit, providing data structures to represent chemical concepts along with methods to manipulate such structures and perform computations on them. The library implements a wide variety of cheminformatics algorithms ranging from chemical structure canonicalization to molecular descriptor calculations and pharmacophore perception. It is used in drug discovery, metabolomics, and toxicology. Over the last 10 years, the code base has grown significantly, however, resulting in many complex interdependencies among components and poor performance of many algorithms. Results: We report improvements to the CDK v2.0 since the v1.2 release series, specifically addressing the increased functional complexity and poor performance. We first summarize the addition of new functionality, such atom typing and molecular formula handling, and improvement to existing functionality that has led to significantly better performance for substructure searching, molecular fingerprints, and rendering of molecules. Second, we outline how the CDK has evolved with respect to quality control and the approaches we have adopted to ensure stability, including a code review mechanism. Conclusions: This paper highlights our continued efforts to provide a community driven, open source cheminformatics library, and shows that such collaborative projects can thrive over extended periods of time, resulting in a high-quality and performant library. By taking advantage of community support and contributions, we show that an open source cheminformatics project can act as a peer reviewed publishing platform for scientific computing software. [ABSTRACT FROM AUTHOR]

Hydrous minerals in the subducting slabs are potential water carriers into the deep mantle, and thus the synthesis of new hydrous phases is significant in our understanding of water circulation throughout the Earth's interior. In this study, we report the two new hydrous phases, Al2SiO6H2 and Al5.5Si4O18H3.5 (hereafter referred to simply as phases Psi and Phi, respectively), which are synthesized in the Al2O3-SiO2-H2O system at 15.5 GPa, 1400°C and 17.5 GPa, 1600°C by using Sakura 2500-ton multi-anvil apparatus. The luminescence spectra of Cr3+ show the phase Psi has characteristic peaks at 687, 693 and 705 nm, while phase Phi has characteristic peaks at 691, 696 and 708 nm. Single-crystal X-ray diffraction (SCXRD) refinements yield a monoclinic structure of both phases (space group P21) with ideal chemical formulae of Al2SiO6H2 and Al5.5Si4O18H3.5, respectively. The determined lattice parameters for phase Psi are a=9.4168±0.0016 Å, b=4.3441±0.0007 Å, c=9.4360±0.002 Å, and β=119.726±0.005° at ambient pressure and 300 K, while the phase Phi has a=7.2549±0.0018 Å, b=4.3144±0.001 Å, c=8.0520±0.002 Å, and β=01.740±0.009° at ambient pressure and 250 K. Electron microprobe analyses (EPMA) show the chemical compositions of phases Psi and Phi to be Al1.99Si0.85O6H2.62 and Al5.58Si2.81O18H8.03, respectively, which slightly deviate from the ideal formulae inferred from SCXRD measurements. This may result from the disorder or substitution of Al and Si by H in the crystal structures under our synthesis conditions. Our study suggests that phases Psi and Phi are the two potential water carriers at the upper part of the mantle transitions zone, providing new insights into how deep water is stored in this region. [ABSTRACT FROM AUTHOR]

Structural characteristics of serpierite samples from Zvezdel, Bulgaria, and Lavrion, Greece, are reported. The thermal behaviour of serpierite from Lavrion is discussed. The chemical composition of the studied samples is analysed by energy-dispersive spectroscopy (EDS) and confirmed by single-crystal structure refinements. The obtained chemical formulas correspond well to that of serpierite with Cu:Zn ratio varying between 2.9 and 5.6. The sample from Zvezdel, with composition Ca[Cu3.3Zn0.7(OH)6(SO4)2•3H2O, crystallizes in the monoclinic crystal system, with space group I2 and unit-cell parameters a = 18.418(3), b = 6.220(1), c = 12.091(2) Å, β = 90.78(1)˚, whereas the one from Lavrion Ca[Cu2.8Zn1.2(OH)6(SO4)2]•3H2O, shows similar unit-cell parameters a = 18.394(1), b = 6.256(1), c = 12.097(1) Å, β = 90.92(1)˚, but higher I2/m space-group symmetry. Both studied crystals exhibit serpierite structure topology, but different stacking sequence of the octahedral layers. While in previously studied serpierite of Sabelli and Zanazzi (Acta Cryst B24:1214-1221, 1968) there are two layers per unit cell, in currently studied samples there is only one. As a consequence, their unit-cell volumes are half than that of the first structurally characterized serpierite specimen with SG C2/c and unit-cell parameters a = 22.186(2), b = 6.250(2), c = 21.853(2) Å, β = 113.36(1)˚. Taking into account the structural peculiarities of the studied samples they are considered as serpierite polytypoids. [ABSTRACT FROM AUTHOR]

With the help of hydrogen bonding and π⋯π stacking, the small molecular clusters in the impregnating solution was induced to self-assemble and form a new Ni–Mo polyoxometalate based on octamolybdate with a molecular formula of [Ni(pyz)6] [Mo8O26(pyz)2]⋅10H2O (pyz = pyrazole). The polyoxometalate was structurally characterized detailed by various technologies, and its sulfide was also characterized to make a preliminary study to explore the use of it as a potential NiMoS active phase precursor. Much more NiMoS active phase and higher catalytic activity of the Ni–Mo sulfided catalyst was found, and the structure-directing effects can account for the phenomenon. The results show the Ni–Mo polyoxometalate [Ni(pyz)6] [Mo8O26(pyz)2]⋅10H2O can make a superior precursor to prepare the hydrodesulfurization catalyst, and it provides a new preparation methodology to the rational design and controllable preparation of superior hydrodesulfurization catalysts. [ABSTRACT FROM AUTHOR]

Layered semiconductor materials have become a serious research topic in recent years, thanks to their effective optical properties. In this article, the thin-film structure of Tl2In2S3Se [(TlInS2)0.75(TlInSe2)0.25] material with layered structure was grown by thermal evaporation method. The structural, morphological, and optical properties of the deposited thin films were examined. X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS) and atomic force microscopy (AFM) techniques were used to get information about structural and morphological properties of the thin films. XRD pattern presented well-defined peaks associated with monoclinic crystalline structure. The crystallite size, dislocation density, and lattice strain of the films were also obtained from the analyses of XRD pattern. EDS analysis showed that atomic compositional ratios of the Tl, In, S, and Se elements are consistent with chemical formula of Tl2In2S3Se. The optical characterization of thin film was performed using transmission and Raman spectroscopy techniques. Raman spectrum offered information about the vibrational modes of the thin film. The analyses of the transmission spectrum presented the indirect and direct band gap energies of the Tl2In2S3Se thin film as 2.23 and 2.52 eV, respectively. The further analyses on the absorption coefficient resulted in Urbach energy of 0.58 eV. [ABSTRACT FROM AUTHOR]

MF-LOGP, a new method for determining a single component octanol–water partition coefficients ( LogP ) is presented which uses molecular formula as the only input. Octanol–water partition coefficients are useful in many applications, ranging from environmental fate and drug delivery. Currently, partition coefficients are either experimentally measured or predicted as a function of structural fragments, topological descriptors, or thermodynamic properties known or calculated from precise molecular structures. The MF-LOGP method presented here differs from classical methods as it does not require any structural information and uses molecular formula as the sole model input. MF-LOGP is therefore useful for situations in which the structure is unknown or where the use of a low dimensional, easily automatable, and computationally inexpensive calculations is required. MF-LOGP is a random forest algorithm that is trained and tested on 15,377 data points, using 10 features derived from the molecular formula to make LogP predictions. Using an independent validation set of 2713 data points, MF-LOGP was found to have an average RMSE = 0.77 ± 0.007, MAE = 0.52 ± 0.003, and R 2 = 0.83 ± 0.003. This performance fell within the spectrum of performances reported in the published literature for conventional higher dimensional models ( RMSE = 0.42–1.54, MAE = 0.09–1.07, and R 2 = 0.32–0.95). Compared with existing models, MF-LOGP requires a maximum of ten features and no structural information, thereby providing a practical and yet predictive tool. The development of MF-LOGP provides the groundwork for development of more physical prediction models leveraging big data analytical methods or complex multicomponent mixtures. [ABSTRACT FROM AUTHOR]

In current research, a novel coordination polymer based on Cu(II) having a 1D spiro-like chain architecture has been created with the reaction between HL (4-(4-(2-chloroimidazo[1,2-a]pyridin-3-yl)-[2,3′-bipyridin]-6-yl)benzoic acid), the custom designed organic ligand and Cu(NO3)2·3H2O under the reaction conditions of solvothermal, and its chemical formula is [Cu(L)2]·2DMF·3H2O (1). At first, the real-time RT-PCR was accomplished for the determination of the miRNA9 expression level in normal tissue and liver cancer tissue. And the compound's influence on the miRNA9 relative expression in the cancer cells was next investigated as well. The western blotting assay was in-depth employed for the determination of the PDGF signaling pathway expression in the liver cancer cells after treated with the new compound. In the end, we investigate the direct regulation of miRNA9 on signaling pathway of PDGF by luciferase reporter gene analysis and bioinformatics analysis. Suggested by the simulation of molecular docking, it is found that the carboxyl group of Cu complex could bind to probe protein, at the same time, the pyridine ring also could bind to the probe protein, and therefore suggested that the Cu complex exhibited excellent biological activities. [ABSTRACT FROM AUTHOR]