Search

A large nonlinear optical (NLO) coefficient and a wide band gap are two crucial but contradictory parameters that are difficult to achieve simultaneously in a single infrared (IR) NLO compound. A salt‐inclusion chalcogenide (SIC), Li[LiCs2Cl][Ga3S6] (1), was prepared that presents a nanosized tunnel framework constructed from monotype chalcogenide tetrahedra. Highly oriented covalent GaS4 tetrahedra in the host lead to a moderate second harmonic generation response (0.7 AgGaS2), and ionic guests effectively broaden the band gap to the widest value (4.18 eV) among all IR NLO chalcogenides, thereby achieving a remarkable balance between NLO efficiency and band gap. [ABSTRACT FROM AUTHOR]

Abstract: Nonlinear optical (NLO) materials with strong second harmonic generation (SHG) responses are technologically and scientifically important for tunable lasers. This work puts forward a new strategy for designing promising infrared nonlinear optical (IR‐NLO) materials with strong SHG responses by strengthening both the static and induced contributions via the high orientation of NLO functional motifs. Two new polyselenides Rb2Ge4Se10 and Cs2Ge4Se10 are studied to verify the strategy, they have 2D infinite ∞ 2[Ge4Se10]2− layers comprising highly oriented distorted GeSe4 tetrahedra. Their large SHG signals (8.0 and 8.5 times that of commercial AgGaS2) can be ascribed to both the static contribution enhancement from the high orientation of the local dipole moment of GeSe4 tetrahedra and the induced contribution enhancement from terminal and SeSe bonded Se atoms. The results confirm the effectiveness of the proposed approaches, shedding light on the exploration of practical IR‐NLO materials with maximized performance. [ABSTRACT FROM AUTHOR]

Objective: To explore the diagnostic efficiency of DNA‐based and RNA‐based quantitative polymerase chain reaction (qPCR) analyses for periprosthetic joint infection (PJI). Methods: To determine the detection limit of DNA‐based and RNA‐based qPCR in vitro, Staphylococcus aureus and Escherichia coli strains were added to sterile synovial fluid obtained from a patient with knee osteoarthritis. Serial dilutions of samples were analyzed by DNA‐based and RNA‐based qPCR. Clinically, patients who were suspected of having PJI and eventually underwent revision arthroplasty in our hospital from July 2014 to December 2016 were screened. Preoperative puncture or intraoperative collection was performed on patients who met the inclusion and exclusion criteria to obtain synovial fluid. DNA‐based and RNA‐based PCR analyses and culture were performed on each synovial fluid sample. The patients’ demographic characteristics, medical history, and laboratory test results were recorded. The diagnostic efficiency of both PCR assays was compared with culture methods. Results: The in vitro analysis demonstrated that DNA‐based qPCR assay was highly sensitive, with the detection limit being 1200 colony forming units (CFU)/mL of S. aureus and 3200 CFU/mL of E. coli. Meanwhile, The RNA‐based qPCR assay could detect 2300 CFU/mL of S. aureus and 11 000 CFU/mL of E. coli. Clinically, the sensitivity, specificity, and accuracy were 65.7%, 100%, and 81.6%, respectively, for the culture method; 81.5%, 84.8%, and 83.1%, respectively, for DNA‐based qPCR; and 73.6%, 100%, and 85.9%, respectively, for RNA‐based qPCR. Conclusions: DNA‐based qPCR could detect suspected PJI with high sensitivity after antibiotic therapy. RNA‐based qPCR could reduce the false positive rates of DNA‐based assays. qPCR‐based methods could improve the efficiency of PJI diagnosis. [ABSTRACT FROM AUTHOR]

The first indiumsilicate oxysulfide Ba2In2Si3O10S ( 1) was obtained by an alkali polychalcogenide flux method through a high-temperature solid-state reaction. It crystallizes in the non-centrosymmetric space group Pca21 (No. 29), with a = 23.060(6), b = 5.2954(6), c = 8.779(2) Å, and Z = 4. Its three-dimensional (3D) framework is constructed from one-dimensional (1D) infinite ∞1[In2O7S2/2] double octahedral chains bridged by corner-sharing Si tetrahedral trimers [Si3O10]8-, yielding a 3D framework with the channels filled with Ba2+ cations along the b direction. It is unprecedented in that the two distorted indium octahedra in 1 face-share to form a [In2O7S2] dimer in indium oxides and oxide chalcogenides. [ABSTRACT FROM AUTHOR]

A new layered compound, Hg5AsS2I3, has been synthesized in the quaternary system mercury/arsenic/chalcogen/halogen by a moderate-temperature solid-state reaction. The compound crystallizes in the space group C2/ c of the monoclinic system, and its structure consists of ∞1[Hg(1)2Hg(2)2As2/2S2] eight-membered-ring chains bridged by Hg atoms to form [Hg(1)2Hg(2)2Hg(3)As2/2S2] layers with inner- and interlayer electrostatic interactions between I and Hg. The optical properties were investigated by means of diffuse reflectance and FTIR spectra. The electronic band structures, along with density of states (DOS) calculations by DFT, indicate that the title compound is a semiconductor, and its optical absorption mainly leads to charge transitions from I-5p, As-4p and S-3p states to Hg-6s states, and both I(1) and I(2) atoms contribute to the top of the valence bands. [ABSTRACT FROM AUTHOR]

The new title compounds are synthesized by solid state reactions of Ba, Ga2S9, Ge (Si), and S in a molar ratio of 2:4:1:4 (quartz tubes, 300 °C for 5 h, 650 °C for 10 h, and 980 °C for 5 d) and characterized by single crystal XRD, IR and UV/VIS/NIR diffuse reflectance spectroscopy, second harmonic generation measurements, laser-induced damage threshold measurements, and DFT electronic band structure calculations. [ABSTRACT FROM AUTHOR]

The title compound, {[Cu4(C3H4NS2)4]·2H2O} n, was produced by diffusing a solution of 2-mercapto­thia­zoline in tetra­hydro­furan into a solution of CuCl in CH3CN at room temperature. The structure is characterized by self-assembled one-dimensional chains that are condensed from butterfly-like [Cu(C3H4NS2)]4 tetrameric units via double S-bridging at opposite ends. The Cu-Cu distances within the Cu4 butterfly cluster are in the range 2.7103 (10)-2.9764 (10) Å, while the shortest Cu⋯Cu intercluster distance is 3.468 (1) Å, much longer than the sum of the van der Waals radii. [ABSTRACT FROM AUTHOR]

The title compound, [[Cu(4)(C(3)H(4)NS(2))(4)] x 2H(2)O](n), was produced by diffusing a solution of 2-mercaptothiazoline in tetrahydrofuran into a solution of CuCl in CH(3)CN at room temperature. The structure is characterized by self-assembled one-dimensional chains that are condensed from butterfly-like [Cu(C(3)H(4)NS(2))](4) tetrameric units via double S-bridging at opposite ends. The Cu[bond]Cu distances within the Cu(4) butterfly cluster are in the range 2.7103 (10)-2.9764 (10) A, while the shortest Cu...Cu intercluster distance is 3.468 (1) A, much longer than the sum of the van der Waals radii.