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Electrosynthesis of hydrogen peroxide (H2 O2 ) in the acidic environment could largely prevent its decomposition to water, but efficient catalysts that constitute entirely earth-abundant elements are lacking. Here we report the experimental demonstration of narrowing the interlayer gap of metallic cobalt diselenide (CoSe2 ), which creates high-performance catalyst to selectively drive two-electron oxygen reduction toward H2 O2 in an acidic electrolyte. The enhancement of the interlayer coupling between CoSe2 atomic layers offers a favorable surface electronic structure that weakens the critical *OOH adsorption, promoting the energetics for H2 O2 production. Consequently, on the strongly coupled CoSe2 catalyst, we achieved Faradaic efficiency of 96.7 %, current density of 50.04 milliamperes per square centimeter, and product rate of 30.60 mg cm-2 h-1 . Moreover, this catalyst shows no sign of degradation when operating at -63 milliamperes per square centimeter over 100 hours.

Copper is currently the material with the most promise as catalyst to drive carbon dioxide (CO₂) electroreduction to produce value-added multicarbon (C₂₊) compounds. However, a copper catalyst on a carbon-based gas diffusion layer electrode often has poor stability—especially when performing at high current densities—owing to electrolyte flooding caused by the hydrophobicity decrease of the gas diffusion layer during operation. Here, we report a bioinspired copper catalyst on a gas diffusion layer that mimics the unique hierarchical structuring of Setaria’s hydrophobic leaves. This hierarchical copper structure endows the CO₂ reduction electrode with sufficient hydrophobicity to build a robust gas–liquid–solid triple-phase boundary, which can not only trap more CO₂ close to the active copper surface but also effectively resist electrolyte flooding even under high-rate operation. We consequently achieved a high C₂₊ production rate of 255 ± 5.7 mA cm–² with a 64 ± 1.4% faradaic efficiency, as well as outstanding operational stability at 300 mA cm–² over 45 h in a flow reactor, largely outperforming its wettable copper counterparts.

Although the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag2 Se on CoSe2 nanobelts relied on diffusion-driven instability. The resultant Turing-type Ag2 Se-CoSe2 material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.5 % anodic energy efficiency. Electrochemical measurements show that the intrinsic OER activity correlates linearly with the length of Ag2 Se-CoSe2 interfaces, determining that such Turing-type interfaces are more active sites for OER. Combing X-ray absorption and computational simulations, we ascribe the excellent OER performance to the optimized adsorption energies for critical oxygen-containing intermediates at the unconventional interfaces.

Electrochemical carbon dioxide reduction reaction (CO2RR) converts CO2 into value-added chemicals and fuels to realize carbon recycling as a means to solve the problems of renewable energy shortage and environmental pollution. Recently, regulation of the oxidation state of catalysts has emerged as an effective method for designing better-performing CO2RR catalysts. The oxidation state of the catalyst was observed to influence the activity and selectivity of CO2RR, which is essentially based on promoting reactant activation, regulating the adsorption of intermediates and facilitating the C–C coupling. The CO2RR performance of various catalysts, such as Cu-based catalysts, non-Cu metal catalysts, atomically dispersed metal catalysts and carbon materials, can be efficiently improved through oxidation state regulation. In this review, we first discuss current understandings on how the oxidation state affects the catalytic properties of catalysts. Then, we summarize recent progress in strategies used to regulate the oxidation state of catalysts and their resultant performances toward CO2RR. In particular, we highlight recent advancements in in situ techniques that are used to uncover the dynamic evolution of the oxidation state of catalysts during CO2RR. We end this review by outlining the challenges and offering our personal perspectives on future research directions in this promising field.

Selective and efficient catalytic conversion of carbon dioxide (CO2) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO2 reduction to oxygenates and hydrocarbons (e.g., C2+ compounds) is the difficulty of coupling carbon-carbon bonds efficiently. Copper in the +1 oxidation state has been thought to be active for catalyzing C2+ formation, whereas it is prone to being reduced to Cu0 at cathodic potentials. Here we report that catalysts with nanocavities can confine carbon intermediates formed in situ, which in turn covers the local catalyst surface and thereby stabilizes Cu+ species. Experimental measurements on multihollow cuprous oxide catalyst exhibit a C2+ Faradaic efficiency of 75.2 ± 2.7% at a C2+ partial current density of 267 ± 13 mA cm-2 and a large C2+-to-C1 ratio of ∼7.2. Operando Raman spectra, in conjunction with X-ray absorption studies, confirm that Cu+ species in the as-designed catalyst are well retained during CO2 reduction, which leads to the marked C2+ selectivity at a large conversion rate.

BACKGROUND Surgical resection is the preferred method for patients with complex liver cancer. But the tumor is in a special position, the surgery is highly risky, postoperative complications can easily occur, and the prognosis is not ideal. AIM To investigate the effectiveness of surgical resection for complex liver cancer and its influencing factors. METHODS Fifty-seven patients who had complicated liver cancer and underwent surgical resection at our hospital from August 2015 to August 2016 were enrolled in this study. All patients were followed for three years, and their postoperative complications, survival, and factors that impacted their survival were analyzed. RESULTS The total incidence of postoperative complications was 45.61%, and the incidence of pleural effusion was the highest at 28.07%. There were no correlations between the 2-year and 3-year survival rates and sex, age, and HbsAg of the patients (P > 0.05). In terms of pathological parameters, the 2-year and 3-year survival rates were significantly different according to the presence of a tumor capsule, degree of liver cirrhosis, satellite or focal lesions, hepatic vein thrombosis, portal vein tumor thrombus, and intraoperative blood loss (P < 0.05). CONCLUSION The effectiveness of surgical resection for complex hepatocellular carcinoma may be affected by factors such as the presence of a tumor capsule, cirrhosis degree, satellite or focal lesions, hepatic vein embolization, portal vein tumor thrombus, and intraoperative blood loss. Therefore, these factors should be controlled and prevented during surgery to help improve patient survival after surgery.

Recently developed solid-state catalysts can mediate carbon dioxide (CO2) electroreduction to valuable products at high rates and selectivities. However, under commercially relevant current densities of > 200 milliamperes per square centimeter (mA cm−2), catalysts often undergo particle agglomeration, active-phase change, and/or element dissolution, making the long-term operational stability a considerable challenge. Here we report an indium sulfide catalyst that is stabilized by adding zinc in the structure and shows dramatically improved stability. The obtained ZnIn2S4 catalyst can reduce CO2 to formate with 99.3% Faradaic efficiency at 300 mA cm−2 over 60 h of continuous operation without decay. By contrast, similarly synthesized indium sulfide without zinc participation deteriorates quickly under the same conditions. Combining experimental and theoretical studies, we unveil that the introduction of zinc largely enhances the covalency of In-S bonds, which “locks” sulfur—a catalytic site that can activate H2O to react with CO2, yielding HCOO* intermediates—from being dissolved during high-rate electrolysis., Developing durable catalysts for carbon dioxide reduction to formate at commercial-scale current densities is challenging. This work reports that indium sulfide stabilized through zinc incorporation can produce formate efficiently and quickly at high current densities over long timescales.

Electrosynthesis of hydrogen peroxide (H

Copper is currently the material with the most promise as catalyst to drive carbon dioxide (CO

Although the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag

Telocytes are novel interstitial cells with a specific structure:the body has an elliptical shape or a triangle shape,with slender and thin protrusions that connect with other cells to form a complex 3D network.This article summarizes the structural characteristics and identification Methods of Telocytes and demonstrates their potential functions as a new target for disease prevention and treatment.

Although the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag2Se on CoSe2 nanobelts relied on diffusion-driven instability. The resultant Turing-type Ag2Se-CoSe2 material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.5% anodic energy efficiency. Electrochemical measurements show that the intrinsic OER activity correlates linearly with the length of Ag2Se-CoSe2 interfaces, determining that such Turing-type interfaces are more active sites for OER. Combing X-ray absorption and computational simulations, we ascribe the excellent OER performance to the optimized adsorption energies for critical oxygen-containing intermediates at the unconventional interfaces. Our work offers opportunities for creating Turing structures in other inorganic nanomaterials with unexplored catalytic abilities.

Selective and efficient catalytic conversion of carbon dioxide (CO

At present, developing a flame-retardant unit to solve the flammability and melt-dripping of poly(ethylene terephthalate) (PET) still is a key issue. To endow PET with good flame retardancy and low smoke releasing, a third monomer, N, N′-bis(2-hydroxyethyl)-biphenyl-3,4,3′,4′-tetracarboxylic diimide (BPDI) containing biphenyl biimide and without any traditional flame-retardant elements, is synthesized and incorporated to the main chain of PET to obtain the P(ET-co-BP)n copolyester via melt polymerization. The thermal stability, combustion and pyrolysis behaviors of the obtained copolyesters have been well investigated. Thermogravimetric analysis (TGA) results demonstrate that introducing BPDI into PET obviously improves its thermal stability and the forming ability of char residue. LOI, vertical UL-94 and cone calorimeter measurements have been applied to investigate the combustion behaviors of P(ET-co-BP)n. The results prove that P(ET-co-BP)n copolyesters containing biphenyl biimide show better fire safety, reflected by lower fire growth rate (FIGRA) and low smoke production. SEM and Raman results suggest that the char layers of P(ET-co-BP)n become denser and mainly consist of polyaromatic species with small and uniform microstructures. The pyrolysis behaviors of the copolyesters are investigated by Py-GC/MS, and the results showed that the biphenyl biimide structure units can lead to rearrangement reactions at high temperature, ultimately forming the phenanthrene ring structures during combustion. Without traditional flame-retardant elements like halogen and phosphorus, this novel PET copolyester is environmentally friendly and more safety.

The foreign body response caused by implanted biomaterials hampers their close integration and thereby result in a failure of the implant or tissue-engineering scaffolds, which represent a huge challenge. Here, we prepare anisotropic micro−/nano-wrinkled surfaces on polydimethylsiloxane that mediates hepatic stellate cell (HSC) responses and hepatic fibrosis. It is found that LX-2 cell attachment and morphology are greatly dependent on the wrinkle sizes. Further, the gene and protein expressions of hepatic fibrosis markers (i.e., α-SMA and Col-I) on wrinkled PDMS surface were reduced compared to the control group. Moreover, anisotropic wrinkled surfaces could accelerate the degradation of collagen by increasing the expression of matrix metalloproteinases (MMPs) and decreasing the formation of MMPs inhibitors. This study provides an effective strategy for reducing the fibrotic response and thus improving the efficacy and safety of novel tissue-engineering scaffolds and implants.

This paper presents a micro-grinding experiment on soda-lime glass to study the surface quality effective factors during micro grinding on hard brittle materials. The process of micro-grinding on soda-lime glass is showed in this paper and micro-grinding equipments are designed, fz(feed rate), ap (grinding depth), vg(Grinding speed) in micro-grinding brittle materials and their effects to surface quality have been discussed by experiments which were carried out on a desktop micro machine developed by NEU. Results proved that fz is the most important factor to the surface quality, and low surface roughness could be achieved by high vg and low fz in micro-grinding soda-lime glass.

The process of micro-grinding on hard brittle glass is shown in this paper, micro-grinding equipments are designed by tools of electroplated diamond, fz(feed rate), ap (grinding depth), vg(Grinding speed) in micro-grinding brittle materials and their effects to surface quality have been discussed. It has been demonstrated that low surface roughness could be achieved by high vg and low fz. The roughness of Soda-lime glass accomplished by fz:100μm/s, ap:30μm, vg:120000rpm in the experiment is about 78nm.