Porous metal oxides in the role of electrochemical CO_(2) reduction reaction

The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction.

Simultaneous realization of high sulfur utilization and lithium dendrite-free via dual-effect kinetic regulation strategy toward lithium-sulfur batteries

With the high theoretical specific capacity and energy density,lithium-sulfur batteries(LSBs)have been intensively studied as promising candidates for energy storage devices.However,LSBs are largely hindered by inferior sulfur utilization and uncontrollable dendritic growth.Herein,a hierarchical functionalization strategy of stepwise catalytic-adsorption-conversion for sulfur species via the synergetic of the efficiently catalytic host cathode and light multifunctional interlayer has been proposed to concurrently address the issues arising on the dual sides of the LSBs.The multi-layer SnS_(2) micro-flowers embedded into the natural three-dimensional(3D)interconnected carbonized bacterial cellulose(CBC)nanofibers are fabricated as the sulfur host that provides numerous catalytic sites for the rapid catalytic conversion of sulfur species.Moreover,the distinctive CBC-based SnO_(2)-SnS_(2) heterostructure network accompanied high conductive carbon nanofibers as the multifunctional interlayer promotes the rapid anchoringdiffusion-conversion of lithium polysulfides,Li^(+)flux redistribution,and uniform Li deposition.LSBs equipped with our strategy exhibit a high reversible capacity of 1361.5 m A h g^(-1)at 0.2 C and superior cycling stability with an ultra-low capacity fading of 0.031%per cycle in 1000 cycles at 1.5 C and 0.046%at 3 C.A favorable specific capacity of 859.5 m A h g^(-1)at 0.3 C is achieved with a high sulfur mass loading of 5.2 mg cm^(-2),highlighting the potential of practical application.The rational design in this work can provide a feasible solution for high-performance LSBs and promote the development of advanced energy storage devices.

Recent progress in rate and cycling performance modifications of vanadium oxides cathode for lithium-ion batteries

The emergency of high-power electrical appliances has put forward higher requirements for the power density of lithium-ion batteries.Vanadium oxides with large theoretical capacities and high operating voltages are considered as prospective alternatives for the cathode of a new generation of lithium-ion batteries.However,the poor rate and cycling performance caused by the sluggish electrons/lithium transportation,irreversible phase changes,vanadium dissolution and large volume changes during the repeated lithium intercalation/deintercalation hinder their commercial development.Several optimizing routes have been carried out and extensively explored to address these problems.Taking V_(2)O_(5),VO_(2)(B),V_(6)O_(13),and V_(2)O_(3)as examples,this article reviewed their crystal structures and lithium storage reactions.Besides,recent progress in modification methods for the electrochemical insufficiencies of vanadium oxides,including nanostructure,heterogeneous atom doping,composite and self-supported electrodes has been systematically summarized and finally,the challenges for the industrialization of vanadium oxide cathodes and their development opportunities are proposed.

TGF-β_1,ADAM12和HB-EGF在原发性肝癌组织中的表达(英文)

Objective: To detect the expression and location of TGF-β1, ADAM12 and HB-EGF in primary hepatic carcinoma and study their effect on the growth and metastasis of hepatoma carcinoma cell. Methods: TGF-β1, ADAM12 and HB-EGF were detected by RT-PCR and immunohistochemistry in 30 cases of hepatic carcinoma tissues, 30 cases of adjacent carci- noma tissues and 5 cases of normal hepatic tissues. Results: RT-PCR analyses showed that the mRNA expression of TGF-β1, ADAM12 and HB-EGF were markedly increased in each hepatic carcinoma tissue compared with its adjacent tissue (P < 0.01), but no signal was detected in normal hepatic tissue. Immunohistochemistry showed the same outcome on the expression of above three factors in hepatic tissues as RT-PCR. Proteins location analyses showed the proteins of TGF-β1, ADAM12 and HB-EGF all distributed in the stroma of hepatic carcinoma tissues. The positive correlation was found between TGF-β1 and ADAM12 (r = 0.6137, P < 0.05), as well as ADAM12 and HB-EGF (r = 0.5763, P < 0.05). The protein expression of TGF-β1, ADAM12 and HB-EGF were correlated with the size of tumors, degree of differentiation of hepatoma carcinoma cells, portal vein thrombus and the metastasis of absorbent glands, especially with hepatic cirrhosis caused by hepatitis B virus. Conclu- sion: TGF-β1, ADAM12 and HB-EGF possibly play an important role in the process of growth, invasion and metastasis of hepatoma carcinoma cell, meanwhile, the above three factors may collectively participate in the transition from hepatic cirrhosis caused by hepatitis B virus to hepatocellular carcinoma.

Review on electrochemical carbon dioxide capture and transformation with bipolar membranes

Anthropogenic carbon dioxide(CO_(2))emission from the combustion of fossil fuels aggravates the global greenhouse effect.The implementation of CO_(2)capture and transformation technologies have recently received great attention for providing a pathway in dealing with global climate change.Among these technologies,electrochemical CO_(2)capture technology has attracted wide attention because of its environmental friendliness and flexible operating processes.Bipolar membranes(BPMs)are considered as one of the key components in electrochemical devices,especially for electrochemical CO_(2)reduction and electrodialysis devices.BPMs create an alkaline environment for CO_(2)capture and a stable pH environment for electrocatalysis on a single electrode.The key to CO_(2)capture in these devices is to understand the water dissociation mechanism occurring in BPMs,which could be used for optimizing the operating conditions for CO_(2)capture and transformation.In this paper,the references and technologies of electrochemical CO_(2)capture based on BPMs are reviewed in detail,thus the challenges and opportunities are also discussed for the development of more efficient,sustainable and practical CO_(2)capture and transformation based on BPMs.

Tribological properties of oil-impregnated polyimide in double-contact friction under micro-oil lubrication conditions

Oil-impregnated porous polyimide(iPPI)materials are usually used as retainer for bearings.In these bearings,balls and rings,balls and retainers are two different kinds of contact.In this paper,the friction and wear properties of iPPI were investigated using steel(disc)–steel(ball)–iPPI(pin)double-contact friction test rig for simulating the actual contact in bearings.The results show that compared with that of iPPI–steel single contact,the friction coefficient of iPPI–steel in double contacts is lower and decreases with the amount of additional oil.The surface of iPPI in single contact suffers more wear compared with that in double contacts.Different from single contact,the worn surfaces of iPPI in double contacts are blackened.The Raman spectra of worn surfaces of balls and discs indicate thatα-Fe_(2)O_(3) and Fe_(3)O_(4) were formed during rubbing of the double contacts.Many nanoscale iron oxide particles are found on the worn surfaces of iPPI in double contacts;on the contrary,few particles could be found on the surface in single contact.In double-contact friction,the nanoscale wear debris penetrates inside the iPPI material through the process of extruding and recycling of oil,which is the mechanism of the blackening of the iPPI worn surfaces.The studies show that the double-contact friction method is a new and effective method to study the friction in bearings,especially for those with polymer retainer.

Does Horizontal-Paradigm Aid Weaken the Governance of Recipient Countries?Evidence from China

China's aid has always been an interesting topic in the field of development economics,and the effectiveness of aid is also a controversial subject in the literature.This paper explores the relationship between China's aid and the governance of its recipient countries from 2000 to 2014.We found that,compared with the vertical paradigm"of traditional donors,China's f,horizontal paradigm‘‘has unique features,promoting the governance of recipient countries.We employed a cross-sectional estimation and panel analysis with several regression methods.While our cross-sectional findings did not yield robust evidence to support a relationship between Chinese aid and its recipients'governance,our panel data regressions found a significant and positive relationship.The results were robust in a dynamic panel,even after correcting for endogeneity.Thus,China's aid has a positive influence on governance with the inclusion of time series.The relationship was found to vary according to aid types.

Enhanced electrochemical performance of SnS nanoparticles/CNTs composite as anode material for sodium-ion battery

SnS nanoparticles/CNTs composite （SnS]CNTs composite） is synthesized by a facile one-pot solvothermal reaction. The structural characterizations reveal pure SnS nanoparticles with the size of less than 10 nm distribute on the surface of CNTs with the diameter of less than 20 nm. The SnS]CNTs composite electrode performs high reversible capacity and good cyclability （365 mAh/g at 50 mA/g after 50 cycles）, which is superior to that of pure SnS electrode synthesized without the adding of CNTs （115.9 mAh/g at 50 mA/g after 50mA/ cycles）. Even increasing the current density to 500mA/g, the SnS]CNTs composite electrode still delivers a reversible capacity up to 210 mAh/g after 100 cycles, nearly two times higher than that of the pure SnS electrode （108 mAh/g after 100 cycles）. The rate performance of the SnS/CNTs composite electrode is also better than that of pure SnS electrode at different current densities from 50mA/g to 800mA/g. The enhanced electrochemical performance of SnS/CNTs composite can be attributed to the adding of CNTs as a flexible and conductive structure supporter and the formation of SnS nanoparticles with small size. The SnS nanoparticles[CNTs composite structure not only benefits for buffering the volume change during charge and discharge process, but also increases the surface area for sufficient electrode-electrolyte contacting, and shortens Na＋ diffusion length, which improves the conductivity and stability of active material and finally provides desirable electrochemical performance.