catena-Poly[[[bis­(methyl­amine)zinc(II)]-μ-4,4′-oxydibenzoato] N,N-dimethyl­acetamide solvate]

In the title zinc(II) coordination polymer, {[Zn(C14H8O5)(CH5N)2]·C4H9NO}n, each Zn(II) cation is tetra­hedrally coordinated by two carboxyl­ato O atoms of two oba anions (H2oba is 4,4′-oxydibenzoic acid), and two N atoms from two methyl­amine mol­ecules. Each oba anion bridges two Zn(II) cations through the two carboxyl­ate groups in a monodentate fashion, forming one-dimensional polymeric chains. These chains are linked via N–H⋯O hydrogen bonds, forming a two-dimensional supra­molecular network

Poly[bis­(2,2′-bipyridine-κ2 N,N′)deca-μ-oxido-dioxidodicopper(II)tetra­vanadium(V)]

The title compound, [Cu2V4O12(C10H8N2)2]n, shows a two-dimensional copper–vanadate layer composed of eight-membered rings, each containing four corner-sharing VO4 tetra­hedra; these are linked through six penta­coordinated CuII atoms with the 2,2′-bipyridine ligands attached and pointing above and below the plane of the layer. The Cu atom is coordinated by two N donors from the 2,2′-bipyridine ligand and three O atoms from three adjacent VO4 units to form a distorted tetragonal pyramid. These layers are further connected by π–π inter­actions between inter­leaving bipyridine ligands of adjacent layers [centroid–centroid distances = 3.63 (1) and 3.68 (1) Å] into a three-dimensional supra­molecular structure

Antibodies to SARS Coronavirus in Civets

Using three different assays, we examined 103 serum samples collected from different civet farms and a market in China in June 2003 and January 2004. While civets on farms were largely free from SARS-CoV infection, ≈80% of the animals from one animal market in Guangzhou contained significant levels of antibody to SARS-CoV, which suggests no widespread infection among civets resident on farms, and the infection of civets in the market might be associated with trading activities under the conditions of overcrowding and mixing of various animal species

Ex Situ Reconstruction-Shaped Ir/CoO/Perovskite Heterojunction for Boosted Water Oxidation Reaction

The oxygen evolution reaction (OER) is the performance-limiting step in the process of water splitting. In situ electrochemical conditioning could induce surface reconstruction of various OER electrocatalysts, forming reactive sites dynamically but at the expense of fast cation leaching. Therefore, achieving simultaneous improvement in catalytic activity and stability remains a significant challenge. Herein, we used a scalable cation deficiency-driven exsolution approach to ex situ reconstruct a homogeneous-doped cobaltate precursor into an Ir/CoO/perovskite heterojunction (SCI-350), which served as an active and stable OER electrode. The SCI-350 catalyst exhibited a low overpotential of 240 mV at 10 mA cm-2 in 1 M KOH and superior durability in practical electrolysis for over 150 h. The outstanding activity is preliminarily attributed to the exponentially enlarged electrochemical surface area for charge accumulation, increasing from 3.3 to 175.5 mF cm-2. Moreover, density functional theory calculations combined with advanced spectroscopy and 18O isotope-labeling experiments evidenced the tripled oxygen exchange kinetics, strengthened metal-oxygen hybridization, and engaged lattice oxygen oxidation for O-O coupling on SCI-350. This work presents a promising and feasible strategy for constructing highly active oxide OER electrocatalysts without sacrificing durability

Nitrogen Doped Macroporous Carbon as Electrode Materials for High Capacity of Supercapacitor

Nitrogen doped carbon materials as electrodes of supercapacitors have attracted abundant attention. Herein, we demonstrated a method to synthesize N-doped macroporous carbon materials (NMC) with continuous channels and large size pores carbonized from polyaniline using multiporous silica beads as sacrificial templates to act as electrode materials in supercapacitors. By the nice carbonized process, i.e., pre-carbonization at 400 °C and then pyrolysis at 700/800/900/1000 °C, NMC replicas with high BET specific surface areas exhibit excellent stability and recyclability as well as superb capacitance behavior (~413 F ⋅ g−1) in alkaline electrolyte. This research may provide a method to synthesize macroporous materials with continuous channels and hierarchical pores to enhance the infiltration and mass transfer not only used as electrode, but also as catalyst somewhere micro- or mesopores do not work well

Mesoporous titanosilicate nanoparticles: facile preparation and application in heterogeneous epoxidation of cyclohexene

Mesoporous titanosilicate nanoparticles with a size of 40 to 75 nm (Nano-Ti-MCM-41) were hydrothermally synthesized from a titanosilicate (TiSil) solution with cetyltrimethylammonium bromide (CTAB) as the template and with a cationic polymer as the size-controlling agent. The particle size is proposed to be controlled by adjusting the size of TiSil-CTA(+) micelles influenced by the charge interaction between negatively charged titanosilicate and polymer cationic ions during the formation of TiSil-CTA+ micelles. The presence of n-hexane and hydrogen peroxide in the preparation process proved to favor a well-ordered mesostructure in these nanoparticles: the mesostructure became disordered without using hexane and hydrogen peroxide although the size of mesoporous titanosilicate particles remained in the nanometer scale. The characterization results showed that Nano-Ti-MCM-41 possesses hierarchical porosity (bimodal mesopores) and an ordered mesoporous structure and that the titanium species are predominately located in tetrahedral framework positions. Nano-Ti-MCM-41 is a highly active catalyst for the epoxidation of cyclohexene with hydrogen peroxide, and displayed higher turnover numbers (TONs) based on the cyclohexene conversions and higher selectivity ratio between cyclohexene epoxide and 1,2-cyclohexanediol compared with traditional Ti-MCM-41 prepared without the cationic polymer. The improved catalytic performances are mainly ascribed to the decrease in the particle size of Ti-MCM-41, resulting in the enhanced accessibility of the reactants to the catalytic Ti species via the shorter channels of Nano-Ti-MCM-41 and in the shorter residence time of cyclohexene epoxide in the mesopores of the nanoparticles. Importantly, the mesoporous titanosilicate nanoparticles are stable catalysts immune to titanium leaching, suggesting their good recyclability potential in the epoxidation with aqueous H2O2.</p

Nanoparticles (NPs)-mediated systemic mRNA delivery to reverse trastuzumab resistance for effective breast cancer therapy

Monoclonal antibody-based therapy has achieved great success and is now one of the most crucial therapeutic modalities for cancer therapy. The first monoclonal antibody authorized for treating human epidermal growth receptor 2 (HER2)-positive breast cancer is trastuzumab. However, resistance to trastuzumab therapy is frequently encountered and thus significantly restricts the therapeutic outcomes. To address this issue, tumor microenvironment (TME) pH-responsive nanoparticles (NPs) were herein developed for systemic mRNA delivery to reverse the trastuzumab resistance of breast cancer (BCa). This nanoplatform is comprised of a methoxyl-poly (ethylene glycol)-b-poly (lactic-co-glycolic acid) copolymer with a TME pH-liable linker (Meo-PEG-Dlinkm-PLGA) and an amphiphilic cationic lipid that can complex PTEN mRNA via electrostatic interaction. When the long-circulating mRNA-loaded NPs build up in the tumor after being delivered intravenously, they could be efficiently internalized by tumor cells due to the TME pH-triggered PEG detachment from the NP surface. With the intracellular mRNA release to up-regulate PTEN expression, the constantly activated PI3K/Akt signaling pathway could be blocked in the trastuzumab-resistant BCa cells, thereby resulting in the reversal of trastuzumab resistance and effectively suppress the development of BCa