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Herein, CuO nanocrystals spatially embedded inside carbon polyhedron (CuO@C) derived via morphology‐preserved transformation of metal–organic frameworks (MOFs) are utilized for high‐performance asymmetric supercapacitors (SCs). Using a conventional MOF (several micrometers in size), pore‐filling with polymer inside MOF (polymer@MOF) via vapor‐phase polymerization (VPP) process was achieved that amount of polymer used for VPP can be readily adjusted to control the carbon content of CuO@C after thermolysis and subsequent oxidation processes. When monodisperse and nano‐sized MOF is used for CuO@C (denoted as nCuO@C_1), it presents superior electrochemical performance because monodispersity and smaller size reduce interfacial resistance and promote mass‐transport property, respectively. Asymmetric SC of nCuO@C_1 with carbon sphere (CS) as a counter electrode presents excellent energy density of 55.47 Wh/kg and long‐term stability of 88.7% at 5000 cycles, comparable to the best MO‐based asymmetric SCs derived from MOFs. [ABSTRACT FROM AUTHOR]

Influences of process temperature on the phase of Ga2O3 thin films grown by atomic layer deposition (ALD) on a sapphire substrate is investigated. Ga2O3 thin films grown by ALD at a process temperature of 200°C showed an amorphous phase; however, crystalline α‐Ga2O3 film was deposited at the deposition temperatures from 225 to 250°C. Above a process temperature of 300°C, α and β phases coexist in the grown Ga2O3 thin film. Interestingly, β‐Ga2O3 thin film was deposited on the sapphire by an increase of working pressure during Ga2O3 ALD process at the process temperature of 300°C. The bandgap of β‐Ga2O3 thin film was as high as ~5.2 eV. A metal–semiconductor–metal type photodetector using the β‐Ga2O3 thin film exhibited a fast response speed with a short rise time of 1.3 μs for the detection of deep ultraviolet wavelengths. [ABSTRACT FROM AUTHOR]

The weak bands around 1100 cm SP -1 sp can be assigned to I v i (O-O) vibrations for the compounds containing peroxo ligands (1095, 1049 cm SP -1 sp for B Cs-1 b , 1093, 1026 cm SP -1 sp for B Rb-1 b , 1078, 1024 cm SP -1 sp for B Cs-2 b , and 1078, 1026 cm SP -1 sp for B Cs-3 b ). The absorption bands near 880 cm SP -1 sp are attributed to I v i (Mo-O) vibrations (894 cm SP -1 sp for B Cs-0 b , 877 cm SP -1 sp for B Rb-0 b , 893 cm SP -1 sp for B Cs-1 b , 881 cm SP -1 sp for B Rb-1 b , 877 cm SP -1 sp for B Cs-2 b , and 875 cm SP -1 sp for B Cs-3 b ). B Cs-1 b and B Rb-1 b initially lose water and decompose to A SB 2 sb Mo SB 3 sb O SB 10 sb (A = Cs or Rb) by losing O SB 2 sb by 600°C, calculated (found): B Cs-1 b ; 6.5% (6.3%), B Rb-1 b ; 10.3% (10.7%). However, final reaction products were identified to be B Cs-0 b (0 mL of H SB 2 sb O SB 2 sb ), B Cs-1 b (~0.3 mL of 30% H SB 2 sb O SB 2 sb ), or B Cs-2 b (~0.6 mL of 30% H SB 2 sb O SB 2 sb ) depending on the added H SB 2 sb O SB 2 sb . [Extracted from the article]

We discovered new biomarker candidates for acute myocardial infarction (AMI) using micro LC and accurate mass spectrometry. Two serum samples were pooled and used for biomarker screening. UHPLC‐LTQ‐Orbitrap analysis was used with data‐dependent acquisition followed by Sequest search. Six biomarker candidates were selected after fold change analysis of peptides in AMI patient samples compared to healthy controls. Literature search results were reflected. The six biomarker candidates were characterized and quantified using multi reaction monitoring using synthesized peptides or trypsin digested protein standards. Levels of obscurin, alpha‐1‐acid glycoprotein 1, and clusterin were significantly increased (p < 0.001) in AMI patient samples compared to levels in healthy controls, while those of antithrombin III and fibrinogen beta were not. We confirmed the diagnostic performance of obscurin and clusterin as biomarker candidates for AMI using commercial ELISA kits. Receiver operating characteristic results showed that obscurin and clusterin showed highest sensitivity and specificity for AMI diagnosis together with troponins by both of multi‐reaction monitoring analysis and ELISA. [ABSTRACT FROM AUTHOR]

Stoichiometrically equivalent noncentrosymmetric (NCS) sodium metal silicates, Na2MgSiO4 and Na2ZnSiO4, and their solid solutions have been synthesized via solid‐state reactions. The structures of the reported materials were determined by powder X‐ray diffraction using the Rietveld method. A careful structural analysis indicates that the unit cell volumes of Na2Mg1−xZnxSiO4 solid solutions decrease as more Zn2+ cations are doped into the site of Mg2+. Also, the synthesized silicate solid solutions revealed three‐dimensional frameworks consisting of highly distorted yet well‐aligned MgO4 (or ZnO4) and SiO4 tetrahedra. The title compounds exhibit very large band gaps ranging from 5.57 to 6.05 eV. Second‐harmonic generation (SHG) measurements indicate that the solid solutions are phase‐matchable and the SHG efficiencies increase as more d10 cation, Zn2+, is added to the backbone. A complete characterization is presented along with the explanation of the structure‐SHG property relationship. [ABSTRACT FROM AUTHOR]

Keywords: Metal salts; Aliphatic acid; SEM; Fibrous morphology EN Metal salts Aliphatic acid SEM Fibrous morphology 29 31 3 01/29/21 20210101 NES 210101 Sodium ion leads a fibrous SEM image for the metal salts of saturated aliphatic acids (C12-24). *The size of metal cation is represented in parenthesis in ppm. gl GLO:1CJF/01jan21:bkcs12155-fig-0003.jpg PHOTO (COLOR): 3 The SEM images of sodium salt of C12-C22 aliphatic acids in 50 K except SA in 100 K expand. [Extracted from the article]

Waste crab shell (CS) is implemented to prepare highly N‐doped and CS‐derived hierarchical porous carbon nanofibers (CSCNs) capable of high‐performance supercapacitors combining with Co3O4 nanocrystals. The fiber nature of the exoskeleton of CSs is transformed to N‐containing organic nanofibers, which are carbonized and subsequently activated by hot CO2 treatment to control the specific surface area (SSA) and pore size distribution (PSD). The interwoven bundles of CSCNs present intrinsic macroporosity whereas mesopores (<10 nm) are generated at the interspace between CSCNs. The CO2‐activated CSCNs show an ultra‐high SSA of 2430 m2/g, combining with N‐doping levels of 2.1 wt %. In addition, highly N‐doped hierarchical CSCNs are utilized as supercapacitors hybridized with Co3O4 nanocrystals (Co3O4@CSCN). The Co3O4@CSCN exhibits superior capacitances of 508 F/g at 1 A/g, outstand rate capacitances and 374 F/g (74%) even at 50 A/g, and excellent long‐term cycling stability of 470 F/g (95%) at 2 A/g over 10 000 cycles. Such excellent electrochemical performance is attributed to the synergic effect of redox sites and electric double layer capacitance of highly porous CSCNs, augmented electric conductivity and wettability due to N‐doping, enhanced charge transfer caused by small crystal sizes and large interfaces of CSCNs, and easy electrolyte diffusion due to the genuine hierarchy of CSCN. [ABSTRACT FROM AUTHOR]

Exploring nonlinear optical crystals with large birefringence in the short‐wavelength ultraviolet (SWUV) regions (≤300 nm) is a valuable pursuit. Herein, KHC2O4·B(OH)3, which is composed of infinite [HC2O4]− and [B(OH)3] chains, was successfully grown via the slow evaporation method. The [HC2O4]− and [B(OH)3] chains endow KHC2O4·B(OH)3 with the largest birefringence (0.164@1064 nm) of all B(OH)3‐containing compounds that have been reported in the SWUV regions. Moreover, it possesses a moderate second‐harmonic generation response (0.3 × KH2PO4) and a short UV cutoff edge of 254 nm. The electron localization function diagram indicates the large birefringence originates from the HC2O4 and B(OH)3 groups. This work provides a new method to investigate crystals with large birefringence in the B(OH)3‐based oxalate system. [ABSTRACT FROM AUTHOR]

Three co‐substituted quaternary and quinary Zintl phases belonging to the Ba1‐xSrxZn2‐yCuySb2 (x = 0, 0.09; 0.24 ≤ y ≤ 0.42) system were prepared by the molten Pb metal‐flux method. Co‐substitution using the cationic Sr and anionic Cu for Ba and Zn was initially applied to lower the thermal conductivities and to improve the electric conductivities of these title compounds simultaneously. The homogeneities of single‐phase products were verified by powder x‐ray diffraction analysis, and the BaCu2S2‐type orthorhombic crystal structures with the Ba/Sr and the Zn/Cu mixed‐sites were refined by single crystal x‐ray diffraction analysis. Structural selectivity for the observed BaCu2S2‐type phase was rationalized by the radius ratio of cationic and anionic elements, where r+/r− > 1. DFT calculations using the three structural models revealed that the Sr and Cu substitutions can increase the structural stability and the hole carrier concentration. A series of temperature‐dependent electrical transport property measurements for BaZn1.76Cu0.24Sb2 and Ba0.91Sr0.09Zn1.70Cu0.30Sb2 successfully proved that the co‐substitution using Sr and Cu enhanced electrical conductivities, but reduced the Seebeck coefficients resulting in the slight change in power factor. [ABSTRACT FROM AUTHOR]

A quaternary Zintl phase Ca SB 1.82(1) sb Eu SB 0.18 sb CdSb SB 2 sb with the Ca SP 2+ sp /Eu SP 2+ sp mixed-cations was successfully synthesized by the Pb metal-flux method and characterized by PXRD and SXRD analyses. Moreover, three specific interatomic interactions between Cd and Sb, Ca/Eu, and Sb (averaged), and Ca1 and Eu are also evaluated by crystal orbital Hamilton population (COHP) analyses. In summary, the quaternary Zintl phase Ca SB 1.82(1) sb Eu SB 0.18 sb CdSb SB 2 sb having the Ca/Eu mixed-site was successfully synthesized by the Pb metal-flux method, and the batch of nicely grown needle-shaped single-crystals was obtained. The observed particular site-preference of Ca and Eu over two available sites are nicely elucidated by both of the size-factor and the electronic-factor criteria, where the relatively larger-sized and less electronegative Eu occupies the Ca1/Eu mixed-site. [Extracted from the article]

Two novel polar intermetallic compounds have been synthesized by a high-temperature reaction method, and their crystal structures have been characterized by both single-crystal and powder X-ray diffractions. La15Ge9Li1 .50(16) crystallizes in the hexagonal space group P63 mc ( Z = 2, Pearson code hP52) with nine crystallographically independent sites in the unit cell, and the lattice parameters are a = 15.516(2) and c = 6.895(2) Å. The overall crystal structure can be described as a √3 × √3 × 1 superstructure of the parent compound La5Ge3 adopting the Mn5Si3-type, and such a superstructure transformation should be attributed to the particular ordering patterns of interstitial Li atoms at the Wyckoff 2 a and 2 b sites with different occupation factors. La7Ge3 also crystallizes in the hexagonal P63 mc space group ( Z = 2, Pearson code hP20) with three La and one Ge non-equivalent sites in the unit cell. The lattice parameters are a = 10.666(1) and c = 6.357(1) Å. The crystal structure of La7Ge3 shares some similarities with La15Ge9Li1.50(16) and its parent compound La5Ge3, such as the one-dimensional (1D) zigzag confacial La6 octahedra chains and the 1D zigzag La atomic chains. Theoretical investigations using tight-binding linear muffin-tin orbital (LMTO) method provide a comprehensive understanding about electronic structures and chemical bonding of two title compounds based upon density of states (DOS) and crystal orbital Hamilton population (COHP) analyses. The solid-state 7Li NMR spectrum measurement proves the existence of two independent interstitial Li positions at two distinctive octahedral sites in La15Ge9Li1.50(16). [ABSTRACT FROM AUTHOR]

A series of carbazole-benzimidazole conjugates and corresponding BF2-complexes ( BODIPYs) are synthesized and characterized. Carbazole-benzimidazole conjugates are synthesized by the condensation of 1-formyl carbazole and phenylene diamines in good yields. Various substituents are introduced into the benzimidazole moiety and subsequent reaction with BF3• Et2O afforded the BF2-complexes in moderate to good yield. The structural and photophysical properties of the synthesized fluorophores are investigated with various spectroscopic techniques such as UV/Vis and fluorescence spectroscopy, cyclic voltammetry and X-ray crystallography. [ABSTRACT FROM AUTHOR]

This study focuses on the photocatalytic degradation efficiency of bisphenol A ( BPA) when H2O2 is used. Based on the Fenton oxidation reaction, Fe ions (3.0, 5.0, and 10.0 mol%) loaded on the external surface of TiO2 nano-sized materials as a photocatalyst were synthesized using a common solvothermal/impregnation hybrid method. With increasing Fe ion loading, the light absorption shifted to a longer wavelength, indicating shorter bandgaps, and the photoluminescence ( PL) intensities decreased dramatically. The photocatalytic activities of two systems, namely a UV/photocatalytic system and an advanced photocatalytic oxidation-type UV/ H2O2 /photocatalytic system, were compared using two types of catalysts, TiO2 and Fe- TiO2 . Slightly more BPA molecules decomposed in the UV/ TiO2 photocatalytic system than the UV/Fe- TiO2 system. On the other hand, the level of BPA destruction was significantly higher in the UV/ H2O2 /Fe- TiO2 system. In particular, BPA molecules at 10.0 ppm were removed completely after only 2 h in the UV/ H2O2 /5.0 mol% Fe- TiO2 photocatalytic system. These results confirm that the added H2O2 promotes the BPA oxidation on the Fe-loaded TiO2 catalytic system. [ABSTRACT FROM AUTHOR]

The article discusses a study on the synthesis, isolation,and identification of both isomers of 3 by nuclear magnetic resonance (NMR) spectroscopic and X-ray crystallographic analyses. Topics covered include the reaction of isomers 1 and 2 in the presence of potassium tertbutoxide at reflux temperature, the molecular structure of minor product 3a obtained by single-crystal X-ray crystallography, and the crystalline structure of 3a.