Construction of an ultra-small hydrazone-linked covalent organic polymer for selective fluorescent detection of ferric ion in aqueous solution.

A novel ultra-small hydrazone-linked covalent organic polymer (UHCOP) was synthesized based on the Schiff-base reaction between 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and 1,4-benzenedicarbohydrazide at room temperature and utilized as a sensitive fluorescent sensor for rapid (<2 min) and selective detection of Fe in aqueous solution. The prepared UHCOP displayed ultra-small size with the diameter of 7.98 ± 0.

Evaluation of GeneXpert vanA/vanB in the early diagnosis of vancomycin-resistant enterococci infection.

Purpose: Vancomycin-resistant enterococci infection is a worrying worldwide clinical problem. To evaluate the accuracy of GeneXpert vanA/vanB in the diagnosis of VRE, we conducted a systematic review in the study.

Methods: Experimental data were extracted from publications until May 03 2021 related to the diagnostic accuracy of GeneXpert vanA/vanB for VRE in PubMed, Embase, Web of Science and the Cochrane Library.

Insight into the positive effect of porous hierarchy in S/C cathodes on the electrochemical performance of Li-S batteries.

Hierarchically porous carbon-supported sulfur material is widely used as a cathode for Li-S batteries because its large surface area and rich porous system provide high sulfur loading, resulting in high specific capacity with stable charge/discharge cycling performance. However, limited attention has been paid to whether the structure of hierarchical porous system affects the final electrochemical performance of Li-S/C batteries. Herein, we present hierarchically structured carbon (WSAC) with varied amounts of mesopores and micropores as a sulfur container for Li-S batteries.

Self-assembly, crystal structures, and properties of metal-2-sulfoterephthalate frameworks based on [M4(μ3-OH)2]6+ clusters (M = Co, Mn, Zn and Cd).

Hydro- and solvo-thermal reactions of d-block metal ions (Mn(2+), Co(2+), Zn(2+) and Cd(2+)) with monosodium 2-sulfoterephthalate (NaH(2)stp) form six 3D coordination polymers featuring cluster core [M(4)(μ(3)-OH)(2)](6+) in common: [M(2)(μ(3)-OH)(stp)(H(2)O)] (M = Co (1), Mn (2) and Zn (3)), [Zn(2)(μ(3)-OH)(stp)(H(2)O)(2)] (4), [Zn(4)(μ(3)-OH)(2)(stp)(2)(bpy)(2)(H(2)O)]·3.5H(2)O (5) and [Cd(2)(μ(3)-OH)(stp) (bpp)(2)]·H(2)O (6) (stp = 2-sulfoterephthalate, bpy = 4,4'-bipyridine and bpp = 1,3-di(4-pyridyl)propane). All these coordination polymers were characterized by single crystal X-ray diffraction, IR spectroscopy, thermogravimetric and elemental analysis.

Characterization of flavonoids in the extract of Sophora flavescens Ait. by high-performance liquid chromatography coupled with diode-array detector and electrospray ionization mass spectrometry.

A method coupling high-performance liquid chromatography (HPLC) with diode-array detector (DAD) and electrospray ionization mass spectrometry (ESI) was established for the separation and characterization of flavonoids in Sophora flavescens Ait. Based on the chromatographic separation of most flavonoids present in S. flavescens Ait.