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C6H18O2S2NaInBr6, orthorhombic, Pmn21 (no. 31), a = 10.5451(3) Å, b = 7.1169(2) Å, c = 13.7034(4) Å, V = 1028.42(5) Å3, Z = 2, Rgt(F) = 0.0354, wRref(F2) = 0.0923, T = 293 K. [ABSTRACT FROM AUTHOR]

C12H32O10Cu2Cl4, monoclinic, P21/n (no. 14), a = 9.0202(4) Å, b = 9.5791(4) Å, c = 13.6994(6) Å, β = 92.555(1)°, V = 1182.53(9) Å3, Z = 2, Rgt(F) = 0.0308, wRref(F2) = 0.0800, T = 293(2) K. [ABSTRACT FROM AUTHOR]

High pressure has become a powerful platform for creating and controlling novel states of matter, including high temperature (Tc) superconductivity. However, the emergent phenomena generally disappear as high pressure is removed and cloud prospects for future applications. Here, from a distinguishing perspective, FeSe1−xSx is reported as 2D van der Waals materials with extraordinary high‐Tc at ambient pressure, where the superconductivity is boosted by extreme "chemical pressure" inside the materials. Superior to external high pressure, isovalent S substitution in FeSe leads to a much greater compression rate within the superconducting iron‐chalcogenide layer, which guarantees an unabridged superconducting dome that peaked at 37.5 K. Density functional theory calculations reveal that the decreased lattice and structural parameters contribute together for the shift of Fe 3dx2−y2 orbital, which creates a new hole‐pocket at the Fermi level that intimately correlated with the enhanced superconductivity. This study demonstrates the design of materials with optimized superconductivity by introducing chemical pressure. [ABSTRACT FROM AUTHOR]

Hybrid iron-based superconductors were synthesized by sonochemical insertion of organic molecules into FeSe layers. High quality of the samples first enabled reliable phase identifications and three structure types were discovered. Structure determination based on neutron data further facilitated the understanding of their structural stability, doping levels and temperature driven structural transitions. [ABSTRACT FROM AUTHOR]

C8N4H10O2BiCl5, monoclinic, P21/a (no. 14, non-standard setting of P21/c), a = 9.1065(5) Å, b = 14.5950(8) Å, c = 12.7159(8) Å, β = 93.557(2)°, V = 1687.28(17) Å3, Z = 4, Rgt(F) = 0.0249, wRref(F2) = 0.0612, T = 273 K. [ABSTRACT FROM AUTHOR]

Due to the limited resources of lithium source and their high price, lithium-ion batteries (LIBs) cannot meet the demands of future large-scale energy storage. Sodium-ion batteries (SIBs) with advantages of the abundant sodium resources and low cost, are one of the most promising alternatives to LIBs. Here, we firstly synthesize a new manganese-based polyanionic compound (Na 3 Mn 2 P 3 O 11) through a simple sol-gel method. The resolved crystal structure indicates that single-phase Na 3 Mn 2 P 3 O 11 compound belongs to the orthorhombic structure. When tested as for cathodes, it displays a poor electrochemical performance with a potential window of 1.8–4.3 V (versus Na/Na+), caused by the Jahn-Teller effect of Mn3+ generated during charging process. In this context, a series of Fe-doped Na 3 Mn 2-x Fe x P 3 O 11 (0.1 ≤ x ≤ 0.5) are prepared to improve the electrochemical performance. Results indicate that Fe substitution of Mn in Na 2 Mn 2-x Fe x P 3 O 11 structure can not only enhance the electrochemical performance, but also increase conductivity and achieve fast reaction kinetics. Noticeably, when iron-doped amount is 0.4, Na 3 Mn 1.6 Fe 0.4 P 3 O 11 exhibits the best cycling (62.7 mA h g−1 at 0.1 C over 100 cycles) and rate performance (19.7 mA h g−1 at 5 C). A novel manganese-based polyanionic compound (Na 3 Mn 2 P 3 O 11) was successfully prepared via a simple sol-gel way, which belongs to orthorhombic system (space group P 2 1 2 1 2 1). The reasonably small Rp and Rwp factors of the Rietveld refinement reveal that single phase can be obtained, and no impurity phases can be detected in Fe-doped Na 3 Mn 2-x Fe x P 3 O 11 (0 ≤ x ≤ 0.5). Moreover, when iron-doped amount is 0.4, it exhibited the best cycling and rate performance. Image 1 • Na 3 Mn 2 P 3 O 11 (space group P 2 1 2 1 2 1) was firstly prepared via a simple sol-gel method. • Rietveld refinement proved existence of Na 3 Mn 2-x Fe x P 3 O 11 (x = 0–0.5) solid solution. • Carbon-coated Fe-doped samples were prepared to improve electrochemical property. • Na3Mn1.6Fe0.4P3O11@C shows a capacity of 62.7 mA h g−1 at 0.1 C over 100 cycles. [ABSTRACT FROM AUTHOR]

Currently, most predictions of metabolic-associated fatty liver disease (MAFLD) in school-aged children utilize indicators that usually predict nonalcoholic fatty liver disease (NAFLD). The present study aimed to develop new predictive models and predictors for children with MAFLD, which could enhance the feasibility of MAFLD screening programs in the future. A total of 331 school-aged overweight/obese children were recruited from six primary schools in Ningbo city, China. Hepatic steatosis and fibrosis were detected with controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), respectively. Machine learning methods were adapted to build a set of variables to predict MAFLD in children. Then, the area under the curve (AUC) of multiple models and indices was compared to predict pediatric MAFLD. Compared with non-MAFLD children, children with MAFLD had more obvious metabolic disturbances, as they had higher anthropometric indicators, alanine aminotransferase, fasting plasma glucose, and inflammation indicators (white blood cell count, hemoglobin, neutrophil count) (all P < 0.05). The optimal variables for all subjects selected by random forest (RF) were alanine aminotransferase, uric acid, insulin, and BMI. The logistic regression (LR) model performed best, with AUC values of 0.758 for males and 0.642 for females in predicting MAFLD. LnAI-BMI, LnAI, and LnAL-WHtR were approving indices for predicting pediatric MAFLD in all participants, boys and girls individually. Conclusions: This study developed LR models and sex-specific indices for predicting MAFLD in overweight/obese children that may be useful for widespread screening and identification of children at high risk of MAFLD for early treatment. What is Known: • Most of the indicators predicting pediatric MAFLD are derived from the predictive indicators for NAFLD, but the diagnostic criteria for MAFLD and NAFLD are not exactly the same. • The accuracy of predictors based on routine physical examination and blood biochemical indicators to diagnose MAFLD is limited. What is New: • This study developed indicators based on routine examination parameters that have approving performance for MAFLD, with AUC values exceeding 0.70. [ABSTRACT FROM AUTHOR]

Recent studies have identified the curative effects of traditional Chinese medicine for constipation. The mechanism of action of Guiren Runchang granules (GRGs) in the treatment of slow transit constipation (STC) was evaluated in this study. Here, we assessed the efficacy of GRG by comparing the differences in fecal characteristics, stool weight, and intestinal transit rate (ITR) among 6 groups (n = 12/group), which were administered three concentrations of GRG, mosapride, and saline. The influence of GRG on the SCF/c-kit pathway, AQP4, and serum motilin of mice was assessed through ELISA, western blot, and immunohistochemical analysis. The dry weight of mouse feces at 24 hr and ITR in the MD (medium-dose GRG; 9.44 g/kg/d) and HD (high-dose GRG; 18.88 g/kg/d) groups was higher than that in the MC (model control) group. The serum motilin of morphine-induced mice level was lower in the MC group than in the NC (normal control) group, and this condition was improved in the HD group. The HD group expressed significantly higher levels of SCF and c-kit protein but lower levels of AQP4 and simultaneously presented more SCF-positive and c-kit-positive cells. However, no differences in the serum SCF level were found among the six groups. Certain concentrations of GRG are effective in STC mice, the potential mechanism of which may be associated with repairing the SCF/c-kit pathway and reducing the expression of AQP4 in the colon. GRG improved the serum motilin level but had no influence on the serum SCF level. [ABSTRACT FROM AUTHOR]

Recent studies have identified the curative effects of traditional Chinese medicine for constipation. The mechanism of action of Guiren Runchang granules (GRGs) in the treatment of slow transit constipation (STC) was evaluated in this study. Here, we assessed the efficacy of GRG by comparing the differences in fecal characteristics, stool weight, and intestinal transit rate (ITR) among 6 groups (n = 12/group), which were administered three concentrations of GRG, mosapride, and saline. The influence of GRG on the SCF/c-kit pathway, AQP4, and serum motilin of mice was assessed through ELISA, western blot, and immunohistochemical analysis. The dry weight of mouse feces at 24 hr and ITR in the MD (medium-dose GRG; 9.44 g/kg/d) and HD (high-dose GRG; 18.88 g/kg/d) groups was higher than that in the MC (model control) group. The serum motilin of morphine-induced mice level was lower in the MC group than in the NC (normal control) group, and this condition was improved in the HD group. The HD group expressed significantly higher levels of SCF and c-kit protein but lower levels of AQP4 and simultaneously presented more SCF-positive and c-kit-positive cells. However, no differences in the serum SCF level were found among the six groups. Certain concentrations of GRG are effective in STC mice, the potential mechanism of which may be associated with repairing the SCF/c-kit pathway and reducing the expression of AQP4 in the colon. GRG improved the serum motilin level but had no influence on the serum SCF level. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) have attracted intensive research interest due to their diverse properties. However, ferromagnetism is not observed in layered TMDs, except for monolayer VSe2. In this study, we report the synthesis of a bulk ferromagnetic material (LiOH)0.1VS2 based on topochemical reactions. The results demonstrate that the (LiOH)0.1VS2 crystal exhibits strong anisotropic ferromagnetism below a critical temperature of 40 K. Calculations uncover that the in-plane strains in a VS2 superlattice can induce large magnetic anisotropic energy, which stabilizes the long-range ferromagnetic order. The findings provide a new approach to induce ferromagnetism in bulk TMD materials. [ABSTRACT FROM AUTHOR]

The nanostructuring of single‐molecule magnets (SMMs) on substrates, in nanotubes and periodic frameworks is highly desired for the future magnetic recording devices. However, the ability to organize SMMs into long‐range ordered arrays in these systems is still lacking. Here, we report the incorporation of magnetic (RECl2(H2O)6)+ (RE=rare earths) molecular groups into the framework of an organic metal halide perovskite (OMHP)—(H2dabco)CsCl3. Intriguingly, we show the incorporated rare‐earth groups self‐organized into long‐range ordered arrays that uniformly and periodically distributed in the A sites of OMHP. The ordered (RECl2(H2O)6)+ groups serve as SMMs in the perovskite frameworks, exhibiting large effective magnetic moment, moderate magnetic anisotropy and two‐step relaxation behavior. With the additional merit of great structural flexibility and multifunction of OMHPs, the preparation of the first SMMs@OMHP magnetic materials furthers the development of molecular spintronics. [ABSTRACT FROM AUTHOR]

The nanostructuring of single‐molecule magnets (SMMs) on substrates, in nanotubes and periodic frameworks is highly desired for the future magnetic recording devices. However, the ability to organize SMMs into long‐range ordered arrays in these systems is still lacking. Here, we report the incorporation of magnetic (RECl2(H2O)6)+ (RE=rare earths) molecular groups into the framework of an organic metal halide perovskite (OMHP)—(H2dabco)CsCl3. Intriguingly, we show the incorporated rare‐earth groups self‐organized into long‐range ordered arrays that uniformly and periodically distributed in the A sites of OMHP. The ordered (RECl2(H2O)6)+ groups serve as SMMs in the perovskite frameworks, exhibiting large effective magnetic moment, moderate magnetic anisotropy and two‐step relaxation behavior. With the additional merit of great structural flexibility and multifunction of OMHPs, the preparation of the first SMMs@OMHP magnetic materials furthers the development of molecular spintronics. [ABSTRACT FROM AUTHOR]

The four new Sr2Mn3Sb2O2-type title compounds are synthesized from stoichiometric mixtures of SrO, A, M (A: Co, Mn; M: Cu, Ag), and Se (alumina crucible, 900-1000 °C, 24-72 h). [ABSTRACT FROM AUTHOR]

Through the incorporation of Pb 2+ into the [Bi 2 O 2 ] layers, the BiPbO 2 Cl nanosheets with layered structure have been successfully synthesized by one-step solvothermal method. The lattice parameters of tetragonal BiPbO 2 Cl are a = 3.9417(2) Å and c = 12.3957(6) Å, where the c value is considerably smaller than previous results. The structure of BiPbO 2 Cl was then readdressed through Rietveld refinement and aberration-corrected scanning transmission electron microscope investigations. The photo-decomposition experiments demonstrated that BiPbO 2 Cl nanosheet exhibits high photocatalytic activity, which is 12.6 times higher than that of BiPbO 2 Cl bulk. The photocurrent measurement suggests a more efficient photoinduced charge separation and transfer in BiPbO 2 Cl nanosheet. [ABSTRACT FROM AUTHOR]

Theorigin of transition metal vacancies and their effects on theproperties of ThCr2Si2-type compounds have beenless studied and poorly understood. Here we carefully investigatethe structure, physical properties, and electronic structure for aseries of lanthanum cobalt arsenides with nominal composition of LaCoxAs2(1.6 ≤ x≤ 2.1). It is revealed that the occupancy of Co can be tunedbetween 1.98(1) and 1.61(1). The structural analyses based on X-rayand neutron diffractions show the existence of Co vacancies resultsfrom charge balance due to the formation of bond between As–As.These Co vacancies affect the magnetic and electrical properties greatly,adjusting the Curie temperature from 205 to 47 K and increasing theresistivity by more than 100%. First-principles calculations indicatethat the Co vacancies weaken the spin polarization and reduce thedensity of states at the Fermi level, resulting in decreased Curietemperature and increased resistivity, respectively. Our results addressthe importance of transition metal vacancies in ThCr2Si2-type materials and offer a reliable route to tune the magnetismof ThCr2Si2-type structure. [ABSTRACT FROM AUTHOR]

Abstract: A novel nonlinear optical (NLO) material Bi2O2CO3 has been successfully developed by the hydrothermal method. It was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, high resolution transmission electron microscopy (HRTEM), UV–vis–NIR diffuse reflectance spectrum (DRS) and photoluminescence (PL) spectra. The band gap was determined to be 3.42 eV, and the PL properties of Eu3+ doped Bi2O2CO3 under UV excitation have also been investigated. The powder second-harmonic generation (SHG) measurement performed on the ground crystal indicates that the NLO efficiency is approximately 5 times as large as that of KDP (KH2PO4) standard. In addition, the origin of large SHG for Bi2O2CO3 was also researched according to its crystal structure. [Copyright &y& Elsevier]

Background. Melanoma is the deadliest type of skin cancer. Until now, its pathological mechanisms, particularly the mechanism of metastasis, remain largely unknown. Our study on the identification of genes in association with metastasis for melanoma provides a novel understanding of melanoma. Methods. From the Gene Expression Omnibus (GEO) database, the gene expression microarray datasets GSE46517, GSE7553, and GSE8401 were downloaded. We made use of R aiming at analyzing the differentially expressed genes (DEGs) between metastatic and nonmetastatic melanoma. R was also used in differentially expressed miRNA (DEM) data mining from GSE18509, GSE19387, GSE24996, GSE34460, GSE35579, GSE36236, and GSE54492 datasets referring to Li's study. Based on the DEG and DEM data, we performed functional enrichment analysis through the application of the DAVID database. Furthermore, we constructed the protein-protein interaction (PPI) network and established functional modules by making use of the STRING database. Through making use of Cytoscape, the PPI results were visualized. We predicted the targets of the DEMs through applying TargetScan, miRanda, and PITA databases and identified the overlapping genes between DEGs and predicted targets, followed by the construction of DEM-DEG pair network. The expressions of these keratinocyte differentiation-involved genes in Module 1 were identified based on the data from TCGA. Results. 239 DEGs were screened out in all 3 datasets, which were inclusive of 21 positively regulated genes and 218 negatively regulated genes. Based on these 239 DEGs, we finished constructing the PPI network which was formed from 225 nodes and 846 edges. We finished establishing 3 functional modules. And we analyzed 92 overlapping genes and 26 miRNA, including 11 upregulated genes targeted by 11 negatively regulated DEMs and 81 downregulated genes targeted by 15 positively regulated DEMs. As proof of the differential expression of metastasis-associated genes, eleven keratinocyte differentiation-involved genes, including LOR, EVPL, SPRR1A, FLG, SPRR1B, SPRR2B, TGM1, DSP, CSTA, CDSN, and IVL in Module 1, were obviously downregulated in metastatic melanoma tissue in comparison with primary melanoma tissue based on the data from TCGA. Conclusion. 239 melanoma metastasis-associated genes and 26 differentially expressed miRNA were identified in our study. The keratinocyte differentiation-involved genes may take part in melanoma metastasis, providing a latent molecular mechanism for this disease. [ABSTRACT FROM AUTHOR]

Abstract: The structure of the hydrothermal-grown nonlinear optical crystal KBe2BO3F2 was investigated. A new structure of the R3̄c space group with cell parameters of a=4.422(1)Å and c=37.524(3)Å was obtained by powder X-ray diffraction and Rietveld refinement. The new structure is a 1×1×2 superstructure of the previously reported R32 structure with a different stacking sequence of (Be2BO3F2)∞ layers along the c axis. The relationship between the refined structure and the experimental results is discussed. A stacking fault mechanism is proposed for the formation of the superstructure as well as the nonuniformity of the hydrothermal-grown KBBF crystals. [Copyright &y& Elsevier]

Vacancy engineering plays vital role in the design of high‐performance electrocatalysts. Here, we introduced coupled cation‐vacancy pairs in Ni‐doped CoSe to achieve boosted hydrogen evolution reaction (HER) activity through a facile topochemical intercalation approach. Adjacent Co vacancy pairs and heteroatom Ni doping contribute together for the upshift of the Se 4pz orbital, which induces larger overlap between the Se 4p and H 1s orbitals. As a result, the free energy of H adsorption can be lowered significantly. With an advanced HER activity of 185.7 mV at 10 mA cm−2, this work provides new direction and guidance for the design of novel electrocatalysts. [ABSTRACT FROM AUTHOR]

Vacancy engineering plays vital role in the design of high‐performance electrocatalysts. Here, we introduced coupled cation‐vacancy pairs in Ni‐doped CoSe to achieve boosted hydrogen evolution reaction (HER) activity through a facile topochemical intercalation approach. Adjacent Co vacancy pairs and heteroatom Ni doping contribute together for the upshift of the Se 4pz orbital, which induces larger overlap between the Se 4p and H 1s orbitals. As a result, the free energy of H adsorption can be lowered significantly. With an advanced HER activity of 185.7 mV at 10 mA cm−2, this work provides new direction and guidance for the design of novel electrocatalysts. [ABSTRACT FROM AUTHOR]

C15H15Cl9I3N3Sb2, monoclinic, C2/c (no. 15), a = 28.2633(7) Å, b = 12.4964(3) Å, c = 9.1542(3) Å, β = 99.5840(10)°, V = 3188.04(15) Å3, Z = 4, Rgt(F) = 0.0274, wRref(F2) = 0.0687, T = 273.15 K. [ABSTRACT FROM AUTHOR]

Polycrystalline BAsx (x = 0.80–1.10) compounds with different boron-to-arsenic elemental molar ratios were synthesized by a high-pressure and high-temperature sintering method. Compared with other ambient-pressure synthesis methods, high pressure can significantly promote the reaction speed as well as the reaction yield. As the content of arsenic increases from x = 0.91 to 1.10, the thermal conductivity of BAsx gradually increases from 53 to 65 W⋅m−1⋅K−1. Furthermore, the temperature dependence of thermal conductivities of these samples reveals an Umklapp scattering due to the increasing phonon population. This work provides a highly efficient method for polycrystalline BAs synthesis. [ABSTRACT FROM AUTHOR]

We report the synthesis, crystal structures and physical properties of three quaternary compounds CsLiCrSe2, RbLiCrS2 and CsLiCrS2, which represent the first discovered ThCr2Si2-type chromium chalcogenides. They all share the same structure with the space group I4/mmm and Cr/Li mixed occupancy without ordering. Specifically, the Cr/Li–S bond length in RbLiCrS2 is found to be close to the low limit of known Cr–S bonds, and so only alkali metals Cs and Rb that are large enough in size can achieve lattice match and form these chromium compounds. Resistivity and magnetic measurements on CsLiCrSe2 and RbLiCrS2 single crystals and CsLiCrS2 powder crystals demonstrate that these compounds are semiconducting and exhibit a spin-glass state at low temperatures. A limited solid solution range exists in the close vicinity of Cr : Li = 1 : 1 for all three compounds. Cr concentration is found to play a vital role in affecting the spin-glass transition temperature TS; the higher the Cr concentration, the higher the TS. [ABSTRACT FROM AUTHOR]

2H-NbSe 2 , a typical layered transition metal dichalcogenide (TMD), has attracted tremendous research interest for its higher superconducting transition temperature (T c = 7.2 K) than T c of other TMDs (2–4 K) and hosting of charge density wave (CDW). The van der Waals (vdW) bonding between NbSe 2 layers makes it a good platform for tuning the crystal structure, CDW, and superconducting gap by intercalation. Here we report the crystal structure and superconductivity of Rb-intercalated NbSe 2 prepared by solid-state reaction. For Rb intercalation with 0 ≤ x ≤ 0.025, there is only one phase with space group P 6 3 / mmc. With Rb intercalation, T c of Rb x NbSe 2 decreases from 7.2 K for x = 0 to 4.2 K for x = 0.025 in an L-shaped way. The suppression rate of T c is similar to the one with magnetic Fe doping, but much quicker than those with Li, Ga, and Cu doping. The superconducting phase diagram of Rb x NbSe 2 is established accordingly and is compared with those of Li x NbSe 2 , Cu x NbSe 2 , Fe x NbSe 2 , and Ga x NbSe 2. The suppression of superconductivity is discussed based on the ionic radius, valence, and magnetism of doping elements and the expansion between the NbSe 2 layers. • With Rb doping, the superconductivity (SC) of NbSe 2 is quickly suppressed in an L-like shape. • The suppression rate of T c is similar to that with magnetic Fe doping, but quicker than those with Li, Ga, and Cu doping. • The quick suppression of SC could be mainly ascribed to larger ionic radius and higher efficiency of electron transfer. [ABSTRACT FROM AUTHOR]

We report a new type of MAX phase (M=transition metals, A=main group elements, and X=C/N), Nb3As2C, designated as 321 phase. It differs from all the previous Mn+1AXn phases in that it consists of an alternate stacking of one MX layer and two MA layers in its unit cell, while only one MA layer is allowed in usual MAX phases. The new 321 phase exhibits a bulk modulus of Nb3As2C up to 225(3) GPa as determined by high‐pressure synchrotron X‐ray diffraction, one of the highest values among MAX phases. Isostructural 321 phases V3As2C, Nb3P2C, and Ta3P2C are also found to exist. First‐principles calculations reveal the outstanding elastic stiffness in 321 phases. Among all 321 phases, Nb3P2C is predicted to have the highest elastic properties. These 321 phases, represented by a chemical formula Mn+1AnX, were added as new members to the MAX family and their other properties deserve future investigations. Get the MAX: A series of MAX phases (M=transition metals, A=main group elements, and X=C/N) with outstanding elastic properties, named 321 phases, is added to the family of MAX phases. 321 phases share common symmetry and constituent units with the conventional Mn+1AXn phases. 321 phases are the first series of MAX phases that can be expressed as Mn+1AnX with n>1. [ABSTRACT FROM AUTHOR]

We report a new type of MAX phase (M=transition metals, A=main group elements, and X=C/N), Nb3As2C, designated as 321 phase. It differs from all the previous Mn+1AXn phases in that it consists of an alternate stacking of one MX layer and two MA layers in its unit cell, while only one MA layer is allowed in usual MAX phases. The new 321 phase exhibits a bulk modulus of Nb3As2C up to 225(3) GPa as determined by high‐pressure synchrotron X‐ray diffraction, one of the highest values among MAX phases. Isostructural 321 phases V3As2C, Nb3P2C, and Ta3P2C are also found to exist. First‐principles calculations reveal the outstanding elastic stiffness in 321 phases. Among all 321 phases, Nb3P2C is predicted to have the highest elastic properties. These 321 phases, represented by a chemical formula Mn+1AnX, were added as new members to the MAX family and their other properties deserve future investigations. [ABSTRACT FROM AUTHOR]

Li4Na2CsB7O14 with unique edge-sharing [BO4]5− tetrahedra, an unprecedented [B14O28]14− cluster, and high anisotropic thermal expansion has been obtained under atmospheric pressure conditions, indicating that high pressure is not essential for obtaining edge-sharing [BO4]5− tetrahedra-containing borates. In addition, Li4Na2CsB7O14 may be used as a thermal expansion material. [ABSTRACT FROM AUTHOR]

Cation-Disordered Li-Excess cathode material with an initial capacity over 300 mAh/g have drawn great attention as cathode materials for lithium batteries. In this work, Li 1.3 Mn 0.4 Ti 0.3 O 2 cathode material with superior capacity was synthesized through the effective content adjustment of Li and Ti by ball milling combined with a high-temperature solid-state method. The synthesized Li 1.3 Mn 0.4 Ti 0.3 O 2 possessed high crystallinity with a uniform particle size. The initial capacity reached 334.9, 230.5 and 127.3 mAh/g at current densities of 10, 50, and 100 mA/g, respectively. The oxidation-reduction of Mn3+/Mn4+, Mn2+/Mn3+ and O2-/O-, contributed to the ultrahigh capacity of Li 1.3 Mn 0.4 Ti 0.3 O 2 was investigated by electrochemical characterization. The density of states in Li 1.3 Mn 0.4 Ti 0.3 O 2 was studied by density functional theory based calculations. The experimental results show that Li 1.3 Mn 0.4 Ti 0.3 O 2 could be promising cathode material for high-energy-density lithium batteries. • Li 1.3 Mn 0.4 Ti 0.3 O 2 cathode material with superior capacity was synthesized through easy method. • The initial capacity reached 334.9 mAh/g at current densities of 10 mA/g at room temperature. • The oxidation-reduction of Mn3+/Mn4+, Mn2+/Mn3+ and O2-/O-, contributed to the ultrahigh capacity of Li 1.3 Mn 0.4 Ti 0.3 O 2 was investigated by electrochemical characterization. • The Mn-O hybridization states dominated the electronic states in the vicinity of the Fermi level. [ABSTRACT FROM AUTHOR]

Layered Co-based chalcogenides ACo2Ch2 (A = Tl, K, Rb and Cs; Ch = Se, S) are believed to adopt the ThCr2Si2-type structure and they all share a similar [CoCh] functional layer. However, their interlayer magnetic interactions show significant differences, with the underlying mechanism still unclear. In this work, the chemical origin of the magnetic interactions in layered KCo2Se2−xSx (0 ≤x≤ 2) solid solution has been investigated by experiments and first-principles calculations. All the members of this solid solution are found to have the tetragonal ThCr2Si2-type structure with the space group I4/mmm. Both a and c lattice constants shrink monotonously with S doping. Ferromagnetic interactions are the same for all the members, even for a member with a similar layer distance to those of the antiferromagnetic TlCo2Se2−xSx. The calculated band structure and density of electronic states of KCo2Se2−xSx and TlCo2Se2−xSx show dramatically different scenarios, which is mainly due to the nature of Tl–Ch and K–Ch chemical bonding. Compared with the Tl chalcogenides, the K counterparts with ionic K–Ch bonds present more localized electronic states in terms of energy, which leads to positive interaction constants in the RKKY model. Our results give the quantitative explanation of the different interlayer couplings in the ACo2Ch2 family, as well as the influence of the intercalating layer on the properties of the functional layers in the ThCr2Si2-type structure. [ABSTRACT FROM AUTHOR]

The driving force of the unidirectional thermal expansion in KZnB3O6 has been studied experimentally and theoretically. Our results show that the low-energy vibrational modes of alkali metals play a crucial role in this unusual thermal behavior. [ABSTRACT FROM AUTHOR]

Layered compounds play an important role in thermoelectric materials exploration, as their thermal and electrical conductivities could be affected by different layers. Herein, we have synthesized a new layered Ba 0.7 K 0.3 Cu 2 Se 2 phase with the ThCr 2 Si 2 structure through 30% K doping on the Ba sites in the pristine orthorhombic BaCu 2 Se 2 . The layered Ba 0.7 K 0.3 Cu 2 Se 2 exhibits intrinsically low lattice thermal conductivity due to its extremely short phonon mean free path. Ba 0.7 K 0.3 Cu 2 Se 2 also features high hole mobility and reasonable Seebeck coefficient at high doping levels. The enhancement of electrical conductivity is mainly ascribed to the increase of the hole concentration and the unchanged high hole mobility. As a result, the peak ZT of Ba 0.7 K 0.3 Cu 2 Se 2 reaches 0.32 at 800 K, which is of significance by comparing to its undoped BaCu 2 Se 2 counterpart. [ABSTRACT FROM AUTHOR]

The identification of catalytically active sites (CASs) in heterogeneous catalysis is of vital importance to design and develop improved catalysts, but remains a great challenge. The CASs have been identified in the low-temperature selective catalytic reduction of nitrogen oxides by ammonia (SCR) over a hollandite manganese oxide (HMO) catalyst with a rod-shaped morphology and one-dimensional tunnels. Electron microscopy and synchrotron X-ray diffraction determine the surface and crystal structures of the one-dimensional HMO rods closed by {100} side facets and {001} top facets. A combination of X-ray absorption spectra, molecular probes with potassium and nitric oxide, and catalytic tests reveals that the CASs are located on the {100} side facets of the HMO rods rather than on the top facets or in the tunnels, and hence semi-tunnel structural motifs on the {100} facets are evidenced to be the CASs of the SCR reaction. This work paves the way to further investigate the intrinsic mechanisms of SCR reactions. [ABSTRACT FROM AUTHOR]

(Na x K y )Fe z Se 2 crystals are prepared by Na, Fe, and Se as starting materials in NaCl/KCl flux at low temperatures~720 °C. It is found that K is more preferred than Na to enter in between FeSe layers and forms the phase. Thus-obtained crystals contain more superconducting phase in volume fraction and exhibit new features in transport property. Our results provide a promising new synthetic route for preparing quality crystals of iron selenide superconductors. [ABSTRACT FROM AUTHOR]

The new title compounds are synthesized by solid state reaction of stoichiometric mixtures of BaO, Co or Mn, Ag, and Se (alumina crucibles, 400 °C for 15 h and 850 °C for 24 h). [ABSTRACT FROM AUTHOR]

The nonlinear optical (NLO) material Bi2O2CO3 is hydrothermally prepared in nanocrystalline form from Bi(NO3)3 and urea in 5:8 molar ratio (autoclave, 180 °C, 24 h). [ABSTRACT FROM AUTHOR]

A series of compounds NaxFe2-yS2+z (0.8 ≤ x ≤ 1; 0.3 ≤ y ≤ 0.6; 0 ≤ z ≤ 0.1) is prepared by solid state reaction of the elements (800 °C, 30-48 h). [ABSTRACT FROM AUTHOR]

(C7NH14)2BiCl5, monoclinic, P21/n (no. 14), a = 13.6087(3) Å, b = 7.4645(2) Å, c = 21.7967(6) Å, β = 104.3220(9)°, V = 2145.34(10) Å3, Z = 4, Rgt(F) = 0.0205, wRref(F2) = 0.0528, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Abstract: Crystal structures of both polymorphs of Li4B2O5 were determined. The high temperature phase crystallized in a monoclinic space group I2/a with lattice constants a=10.2269(18)Å, b=4.6988(5)Å, c=8.7862(16)Å, and β=93.562(14)°, while the low temperature one crystallized in an orthorhombic space group Pca21 with lattice constants a=10.1497(8)Å, b=4.7365(5)Å, c=17.5880(14)Å. Though the lattice of the low temperature phase is of higher symmetry than that of the high temperature one, the structure itself loses symmetry elements when it transforms from the high temperature phase to the low temperature polymorph. The bond strain associated with the high temperature structure is supposed to be the reason for the phase transition. A slight increase in volume per formula unit was observed when Li4B2O5 transforms from the high temperature polymorph to low temperature structure, which is quite unusual and has to be studied further. [Copyright &y& Elsevier]

6H-SiC (0001) deposited 300 nm thick AlN film by MOCVD was used as the substrate to grow AlN crystals by the physical vapour transport (PVT) method. It was confirmed that c-axis oriented AlN films were grown and this material had a 3D growth mode. The root mean square (RMS) value for the film was measured to be 2.17 nm. Nucleation and further growth of AlN on so prepared substrate was investigated. Colorless and transparent AlN crystal with 1 mm thick and 40 mm in diameter was obtained after 4 h growth on this substrate. The transparent AlN showed strong (0001) texture XRD patterns, only the (0002) reflection was observed in symmetric θ-2θ scans. The full width at half maximum for a (0002) X-ray rocking curve was less than 0.1° indicating good crystalline quality. Anisotropic etchings in molten KOH shows that the growth (0001) plane exposed to the AlN source predominately has an aluminum polarity, no N-polar inversion domains were observed. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Graphene covered SiC powder (GCSP) has been fabricated by well established method of high temperature thermal decomposition of SiC. The structural and photocatalystic characteristics of the prepared GCSP were investigated and compared with that of the pristine SiC powder. Under UV illumination, more than 100% enhancement in photocatalystic activity is achieved in degradation of Rhodamine B (Rh B) by GCSP catalyst than by pristine SiC powder. The possible mechanisms underlining the observed results are discussed. The results suggested that GCSP as a composite of graphene based material has great potential for use as a high performance photocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the role of impurities in the process of crystal growth is not only of long-standing fundamental interest but is also important for controlling the morphologies and properties of micro/nanocrystals. In this paper, large quantities of single crystal AlN triangular microfibers were synthesized by physical vapor transport (PVT) method with the presence of Ni. We found that AlN triangular microfibers were evolved from hexagonal microfibers with the increase in growth time and Ni plays an important role in the process of evolvement. Then, the effect of Ni on the growth kinetics of AlN triangular microfibers was also investigated. Our results show that the relative radial growth rates of AlN (R/R 0) mostly reduce with the increase of mole ratio of Ni to AlN powders (C i ). The relation between R/R 0 and C i can be well fitted by competitive adsorption model (CAM). Three new red photoluminescence bands centered at about 600, 650 and 690nm were observed in AlN triangular microfibers. At last, three important roles of Ni in the growth of single crystal AlN microfibers could be summarized, which provide useful information for controlling the morphology, size and property of AlN nano/micro-structures. [Copyright &y& Elsevier]

Identification of catalytically active sites in heterogeneous catalysis is of great importance to both development of improved catalysts and investigation of intrinsic reaction mechanisms. In their Communication on page 9619 ff., X. Tang et al. discuss the accurate identification of the active site of selective catalytic reduction of nitrogen oxides by ammonia over a rod ‐ shaped hollandite manganese oxide (HMO), which is located on the {100} side facet of the HMO rod and consists of surface lattice oxygen assembly with a semi ‐ tunnel structural motif. [ABSTRACT FROM AUTHOR]

Borates are among a class of compounds that exhibit rich structural diversity and find wide applications. The formation of edge-sharing (es-) BO4 tetrahedra is extremely unfavored according to Pauling's third and fourth rules. However, as the first and the only es-borate obtained under ambient pressure, es-KZnB3O6 shows an unexpected high thermal stability up to its melting point. The origin of this extraordinary stability is still unclear. Here, we report a novel property in KZnB3O6: unidirectional thermal expansion, which plays a role in preserving es-BO4 from disassociation at elevated temperatures. It is found that this unusual thermal behavior originates from cooperative rotations of rigid groups B6O12 and Zn2O6, driven by anharmonic thermal vibrations of K atoms. Furthermore, a detailed calculation of phonon dispersion in association with this unidirectional expansion predicts the melting initiates with the breakage of the link between BO3 and es-BO4. These findings will broaden our knowledge of the relationship between structure and property and may find applications in future. [ABSTRACT FROM AUTHOR]

From a series of KxFe2Se2(NH3)y (x = 0.1-1.0) samples prepared by intercalation of K into β-FeSe in liquid NH3, K0.3Fe2Se2(NH3)0.47 and K0.6Fe2Se2(NH3)0.37 are obtained as pure phases of the 44 K and 30 K superconducting systems, respectively. [ABSTRACT FROM AUTHOR]

The structures of two Li4B2O5 polymorphs are determined by single crystal XRD and DFT calculations. [ABSTRACT FROM AUTHOR]