Development of advanced anion exchange membrane from the view of the performance of water electrolysis cell

Green hydrogen produced by water electrolysis combined with renewable energy is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.Among water electrolysis technologies,the anion exchange membrane(AEM) water electrolysis has gained intensive attention and is considered as the next-generation emerging technology due to its potential advantages,such as the use of low-cost non-noble metal catalysts,the relatively mature stack assembly process,etc.However,the AEM water electrolyzer is still in the early development stage of the kW-level stack,which is mainly attributed to severe performance decay caused by the core component,i.e.,AEM.Here,the review comprehensively presents the recent progress of advanced AEM from the view of the performance of water electrolysis cells.Herein,fundamental principles and critical components of AEM water electrolyzers are introduced,and work conditions of AEM water electrolyzers and AEM performance improvement strategies are discussed.The challenges and perspectives are also analyzed.

Recent advances and future prospects on Ni_(3)S_(2)-Based electrocatalysts for efficient alkaline water electrolysis

Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.However,efficient and economic H_(2) production by alkaline water electrolysis is hindered by the sluggish hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Therefore,it is imperative to design and fabricate high-active and low-cost non-precious metal catalysts to improve the HER and OER performance,which affects the energy efficiency of alkaline water electrolysis.Ni_(3)S_(2) with the heazlewoodite structure is a potential electrocatalyst with near-metal conductivity due to the Ni–Ni metal network.Here,the review comprehensively presents the recent progress of Ni_(3)S_(2)-based electrocatalysts for alkaline water electrocatalysis.Herein,the HER and OER mechanisms,performance evaluation criteria,preparation methods,and strategies for performance improvement of Ni_(3)S_(2)-based electrocatalysts are discussed.The challenges and perspectives are also analyzed.

Prospective Cohort Investigation on Physical Activity of Osteoporosis Outcomes(PAOPO)in Jidong:Objectives,Study Design,and Baseline Characteristics

Objective The aim of this study was to investigate the prospective association between physical activity(PA),independently or in conjunction with other contributing factors,and osteoporosis(OP)outcomes.Methods The Physical Activity in Osteoporosis Outcomes(PAOPO)study was a community-based cohort investigation.A structured questionnaire was used to gather the participants’sociodemographic characteristics.Bone mineral density(BMD)measurements were performed to assess OP outcomes,and the relationship between BMD and OP was evaluated within this cohort.Results From 2013 to 2014,8,471 participants aged 18 years and older were recruited from Tangshan,China’s Jidong community.Based on their PA level,participants were categorized as inactive,moderately active,or very active.Men showed higher physical exercise levels than women across the activity groups.BMD was significantly higher in the very active group than in the moderately active and inactive groups.Individuals aged>50 years are at a higher risk of developing OP and osteopenia.Conclusion The PAOPO study offers promising insights into the relationship between PA and OP outcomes,encouraging the implementation of PA in preventing and managing OP.

Effects of thermal activation conditions on the microstructure regulation of corncob-derived activated carbon for hydrogen storage

Activated carbons derived from corncob （CACs） were prepared by pyrolysis carbonization and KOH activation. Through modifying activation conditions, samples with large pore volume and ultrahigh BET specific surface area could be obtained. The sample achieved the highest hydrogen uptake capacity of 5.80 wt% at 40 bar and -196℃ The as-obtained samples were characterized by N2-sorption, transmission electron microscopy （TEM） and scanning electron microscopy （SEM）. Besides, thermogravimetric analysis was also employed to investigate the activation behavior of CACs. Detailed investigation on the activation parameters reveals that moderate activation temperature and heating rate are favorable for preparing CACs with high surface area, large pore volume and optimal pore size distribution. Meanwhile, the micropore volume between 0.65 nm and 0.85 nm along with BET surface area and total pore volume has great effects on hydrogen uptake capacities. The present results indicate that CACs are the most promising materials for hydrogen storage application.

Pore size effects of nanoporous carbons with ultra-high surface area on high-pressure hydrogen storage

In this work, the morphologies and pore structures of a series of corncob-derived activated carbons and zeolite templated carbon with ultrahigh surface area were carefully investigated by SEM, HRTEM and N2-sorption characterization technologies. The high-pressure hydrogen uptake performance was analyzed using standard Pressure-Composition-Temperature apparatus in order to study the pore size effects on hydrogen uptake. These as-obtained porous carbons showed different characteristics of pore size distribution as well as specific surface area. The results indicate that the most effective pores for adsorbing hydrogen depended on the storage pressure. These ultramicropores （0.65-0.85 nm） could be the most effective pores on excess H2 uptake at 1 bar, however, micropores （0.85-2 nm） would play a more important role in excess H2 uptake at higher pressure at 77 K. At room temperature, pore size effects on H2 uptake capacity were very weak. Both specific surface area and total pore volume play more important roles than pore size for H2 uptake at room temperature, which was clearly different from that at 77 K. For applications in future, the corncob-derived activated carbons can be more available than zeolite templated carbons at 77 K. Element doping enhanced hydrogen uptake could be main research direction for improving H2 uptake capacity at room temperature.

SnO_2/corncob-derived activated carbon nanohybrid as an anode material for lithium-ion batteries

A facile synthesis of Sn O2/corncob-derived activated carbon（CAC） composite was proposed,and the CAC used here has high specific surface area（over 3000 m2/g） and ample oxygen-containing functional groups.The microstructures and morphology as well as electrochemical performance of the Sn O2/CAC composites were investigated by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and relevant electrochemical characterization. The results show that the mass ratios of Sn O2 to CAC have a significant effect on the structures and properties of the composites. The sample with 34% Sn O2 delivered a capacity of 879.8 m Ah/g in the first reversible cycle and maintained at 634.0 m Ah/g（72.1% retention of the initial reversible capacity） after 100 cycles at a current density of 200 m A/g. After 60 cycles at different specific currents from 200 to 2000 m A/g,the reversible specific capacity was still maintained at 632.8 m Ah/g at a current density of 200 m A/g. These results indicate that SnO 2/CAC can be a desirable alternative anode material for lithium ion batteries.

Clinical Observation of the Treatment of Hemorrhoids with Polyvinyl Alcohol Foam Sclerotherapy under Transparent Cap Assisted Endoscope

Objective:To explore the clinical efect of domestic capsosol foam sclerotherapy in the treatment of hemorrhoids under transparent cap assisted endoscope.Methods:According to the experimental requirements,120 cases of hemorrhoids hospitalized in gastroenterology department in our hospital from February to December in 2019 were selected as the treatment group.The foam sclerotherapy of polidocanol and the air in accordance with the 1:4 ratio was injected into varicose hemorrhoids and hemorrhoids through a transparent cap assisted endoscope.At the same time,100 patients were selected as the control group and the patients were treated according to the routine protocol.The symptom score and climical eficacy of the two groups were observed under different treatment schemes.Results:120 patients were sucessfuly injected with foam sclerotherapy under endoscope.There were significant differences in climical symptom score and climical efficacy between the injection sclerotherapy goup and the control group.There were statistically significant differences in the bleeding,prolapse,painful defecation,anal foreign body sensation,impact on daily work,and hemonhoids data between the treatment group and the contol group(P-0.05).Conclusion:Transparent cap assisted endoscopic injection of polidocanol sclerotherapy in the treatment of hemorhoids can effectively improve the clinical symptoms of patients,promote the improvement of the disease,and the curative effect is satisfactory.It is a new method of minimally invasive treatment of hemorrhoids,which is worthy of wide promotion in clinical practice.

Boosting cartilage repair with silk fibroin-DNA hydrogel-based cartilage organoid precursor

Osteoarthritis(OA),a common degenerative disease,is characterized by high disability and imposes substantial economic impacts on individuals and society.Current clinical treatments remain inadequate for effectively managing OA.Organoids,miniature 3D tissue structures from directed differentiation of stem or progenitor cells,mimic native organ structures and functions.They are useful for drug testing and serve as active grafts for organ repair.However,organoid construction requires extracellular matrix-like 3D scaffolds for cellular growth.Hydrogel microspheres,with tunable physical and chemical properties,show promise in cartilage tissue engineering by replicating the natural microenvironment.Building on prior work on SF-DNA dual-network hydrogels for cartilage regeneration,we developed a novel RGD-SF-DNA hydrogel microsphere(RSD-MS)via a microfluidic system by integrating photopolymerization with self-assembly techniques and then modified with Pep-RGDfKA.The RSD-MSs exhibited uniform size,porous surface,and optimal swelling and degradation properties.In vitro studies demonstrated that RSD-MSs enhanced bone marrow mesenchymal stem cells(BMSCs)proliferation,adhesion,and chondrogenic differentiation.Transcriptomic analysis showed RSD-MSs induced chondrogenesis mainly through integrin-mediated adhesion pathways and glycosaminoglycan biosynthesis.Moreover,in vivo studies showed that seeding BMSCs onto RSD-MSs to create cartilage organoid precursors(COPs)significantly enhanced cartilage regeneration.In conclusion,RSD-MS was an ideal candidate for the construction and long-term cultivation of cartilage organoids,offering an innovative strategy and material choice for cartilage regeneration and tissue engineering.

Bone/cartilage targeted hydrogel: Strategies and applications

The skeletal system is responsible for weight-bearing,organ protection,and movement.Bone diseases caused by trauma,infection,and aging can seriously affect a patient’s quality of life.Bone targeted biomaterials are suitable for the treatment of bone diseases.Biomaterials with bone-targeted properties can improve drug utilization and reduce side effects.A large number of bone-targeted micro-nano materials have been developed.However,only a few studies addressed bone-targeted hydrogel.The large size of hydrogel makes it difficult to achieve systematic targeting.However,local targeted hydrogel still has significant prospects.Molecules in bone/cartilage extracellular matrix and bone cells provide binding sites for bone-targeted hydrogel.Drug delivery systems featuring microgels with targeting properties is a key construction strategy for bone-targeted hydrogel.Besides,injectable hydrogel drug depot carrying bone-targeted drugs is another strategy.In this review,we summarize the bone-targeted hydrogel through application environment,construction strategies and disease applications.We hope this article will provide a reference for the development of bone-targeted hydrogels.We also hope this article could increase awareness of bone-targeted materials.

M2 macrophage-derived exosomes promote diabetic fracture healing by acting as an immunomodulator

Diabetes mellitus is a chronically inflamed disease that predisposes to delayed fracture healing.Macrophages play a key role in the process of fracture healing by undergoing polarization into either M1 or M2 subtypes,which respectively exhibit pro-inflammatory or anti-inflammatory functions.Therefore,modulation of macrophage polarization to the M2 subtype is beneficial for fracture healing.Exosomes perform an important role in improving the osteoimmune microenvironment due to their extremely low immunogenicity and high bioactivity.In this study,we extracted the M2-exosomes and used them to intervene the bone repair in diabetic fractures.The results showed that M2-exosomes significantly modulate the osteoimmune microenvironment by decreasing the proportion of M1 macrophages,thereby accelerating diabetic fracture healing.We further confirmed that M2-exosomes induced the conversion of M1 macrophages into M2 macrophages by stimulating the PI3K/AKT pathway.Our study offers a fresh perspective and a potential therapeutic approach for M2-exosomes to improve diabetic fracture healing.

The horizon of bone organoid: A perspective on constructionand application

Bone defects repair and regeneration by various causes such as tumor resection, trauma, degeneration, etc. havealways been a key issue in the clinics. As one of the few organs that can regenerate after adulthood, bone itselfhas a strong regenerative ability. In recent decades, bone tissue engineering technology provides various types offunctional scaffold materials and seed cells for bone regeneration and repair, which significantly accelerates thespeed and quality of bone regeneration, and many clinical problems are gradually solved. However, the bonemetabolism mechanism is complicated, the research duration is long and difficult, which significantly restrictsthe progress of bone regeneration and repair research. Organoids as a new concept, which is built in vitro withthe help of tissue engineering technology based on biological theory, can simulate the complex biologicalfunctions of organs in vivo. Once proposed, it shows broad application prospects in the research of organdevelopment, drug screening, mechanism study, and so on. As a complex and special organ, bone organoidconstruction itself is quite challenging. This review will introduce the characteristics of bone microenvironment,the concept of organoids, focus on the research progress of bone organoids, and propose the strategies for boneorganoid construction, study direction, and application prospects.

Nano-needle strontium-substituted apatite coating enhances osteoporotic osseointegration through promoting osteogenesis and inhibiting osteoclastogenesis

Implant loosening remains a major clinical challenge for osteoporotic patients.This is because osteoclastic bone resorption rate is higher than osteoblastic bone formation rate in the case of osteoporosis,which results in poor bone repair.Strontium(Sr)has been widely accepted as an anti-osteoporosis element.In this study,we fabricated a series of apatite and Sr-substituted apatite coatings via electrochemical deposition under different acidic conditions.The results showed that Ca and Sr exhibited different mineralization behaviors.The main mineralization products for Ca were CaHPO4⋅2H2O and Ca3(PO4)2 with the structure changed from porous to spherical as the pH values increased.The main mineralization products for Sr were SrHPO4 and Sr5(PO4)3OH with the structure changed from flake to needle as the pH values increased.The in vitro experiment demonstrated that coatings fabricated at high pH condition with the presence of Sr were favorable to MSCs adhesion,spreading,proliferation,and osteogenic differentiation.In addition,Sr-substituted apatite coatings could evidently inhibit osteoclast differentiation and fusion.Moreover,the in vivo study indicated that nano-needle like Sr-substituted apatite coating could suppress osteoclastic activity,improve new bone formation,and enhance bone-implant integration.This study provided a new theoretical guidance for implant coating design and the fabricated Sr-substituted coating might have potential applications for osteoporotic patients.

Calcium phosphate-based materials regulate osteoclast-mediated osseointegration

Calcium phosphate-based materials(CaP)have been widely used as bone graft substitutes with a decent osseointegration.However,the mechanism whereby cells function and repair the bone defect in CaP micro-environment is still elusive.The aim of this study is to find the mechanism how osteoclast behaviors mediate bone healing with CaP scaffolds.Recent reports show that behaviors of osteoclast are closely related with osteogenesis,thus we make a hypothesis that active osteoclast behaviors induced by CaP facilitate bone healing.Here,we found a new mechanism that CaP can regulate osteoclast-mediated osseointegration.Calcium phosphate cement(CPC)is selected as a representative CaP.We demonstrate that the osteoclast-mediated osseointegration can be strongly modulated by the stimulation with CaP.An appropriate Ca/P ratio in CaP can effectively promote the RANKL-RANK binding and evoke more activated NF-κB signaling transduction,which results in vigorous osteoclast differentiation.We observe significant improvement of bone healing in vivo,owing to the active coupling effect of osteoclasts.What is more noteworthy is that the phosphate ions released from CaP can be a pivotal role regulating osteoclast activity by changing Ca/P ratio readily in materials.These studies suggest the potential of harnessing osteoclast-mediated osteogenesis in order to develop a materials-manipulated approach for improving osseointegration.

Oxygen-doped carbon host with enhanced bonding and electron attraction abilities for efficient and stable SnO_2/carbon composite battery anode

The coupling between electrochemically active material and conductive matrix is vitally important for high efficiency lithium ion batteries （LIBs）. By introducing oxygen groups into the nanoporous carbon framework, we accom- plish sustainably enhanced electrochemical performance for a SnO2/carbon LIB. 2-5 nm SnO2 nanoparticles are hydro- thermally grown in different nanoporous carbon frameworks, which are pristine, nitrogen- or oxygen-doped carbons. Compared with pristine and nitrogen-doped carbon hosts, the SnO2/oxygen-doped activated carbon （OAC） composite ex- hibits a higher discharge capacity of 1,122mAhg^-1 at 500 mA g^-1 after 320 cycles operation and a larger lithium storage capacity up to 680 mAhg-I at a high rate of 2,000 mA g^-1. The exceptional electrochemical performance originated from the oxygen groups, which could act as Lewis acid sites to attract electrons effectively from Sn during the charge process, thus accelerating reversible conversion of Sn to SnO2. Meanwhile, SnO2 nanoparticles are effectively bonded with carbon through such oxygen groups, thus preventing the electrochemical sintering and maintaining the cycling stability of the SnO2/OAC composite anode. The high electrochemical performance, low biomass cost, and facile preparation renders the SnO2/OAC composites a promising candidate for anode materials.

SVM based layout retargeting for fast and regularized inverse lithography

Inverse lithography technology(ILT),also known as pixel-based optical proximity correction(PB-OPC),has shown promising capability in pushing the current 193 nm lithography to its limit.By treating the mask optimization process as an inverse problem in lithography,ILT provides a more complete exploration of the solution space and better pattern fidelity than the traditional edge-based OPC.However,the existing methods of ILT are extremely time-consuming due to the slow convergence of the optimization process.To address this issue,in this paper we propose a support vector machine(SVM)based layout retargeting method for ILT,which is designed to generate a good initial input mask for the optimization process and promote the convergence speed.Supervised by optimized masks of training layouts generated by conventional ILT,SVM models are learned and used to predict the initial pixel values in the‘undefined areas’of the new layout.By this process,an initial input mask close to the final optimized mask of the new layout is generated,which reduces iterations needed in the following optimization process.Manufacturability is another critical issue in ILT;however,the mask generated by our layout retargeting method is quite irregular due to the prediction inaccuracy of the SVM models.To compensate for this drawback,a spatial filter is employed to regularize the retargeted mask for complexity reduction.We implemented our layout retargeting method with a regularized level-set based ILT(LSB-ILT)algorithm under partially coherent illumination conditions.Experimental results show that with an initial input mask generated by our layout retargeting method,the number of iterations needed in the optimization process and runtime of the whole process in ILT are reduced by 70.8%and 69.0%,respectively.

Regularized level-set-based inverse lithography algorithm for IC mask synthesis

Inverse lithography technology(ILT)is one of the promising resolution enhancement techniques,as the advanced IC technology nodes still use the 193 nm light source.In ILT,optical proximity correction(OPC)is treated as an inverse imaging problem to find the optimal solution using a set of mathematical approaches.Among all the algorithms for ILT,the level-set-based ILT(LSB-ILT)is a feasible choice with good production in practice.However,the manufacturability of the optimized mask is one of the critical issues in ILT;that is,the topology of its result is usually too complicated to manufacture.We put forward a new algorithm with high pattern fidelity called regularized LSB-ILT implemented in partially coherent illumination(PCI),which has the advantage of reducing mask complexity by suppressing the isolated irregular holes and protrusions in the edges generated in the optimization process.A new regularization term named the Laplacian term is also proposed in the regularized LSB-ILT optimization process to further reduce mask complexity in contrast with the total variation(TV)term.Experimental results show that the new algorithm with the Laplacian term can reduce the complexity of mask by over 40%compared with the ordinary LSB-ILT.

A novel snail-inspired bionic design of titanium with strontium-substituted hydroxyapatite coating for promoting osseointegration

As the population ages,more and more people are suffering from osteoarthritis(OA),resulting in an increasing requirement for joint implants.Surface modification to improve the topology and composition of the implants has been proved to be an effective way to improve the primary stability and long-term success rate of joint implants.In this work,a bionic micro/nano-structure accompanied with a strontium-substituted hydroxyapatite(SrHA)coating was fabricated on titanium(Ti)surface via electrochemical corrosion,ultrasonic treatment,and hydrothermal deposition methods.Thein vitro study demonstrated that the bionic structure and the bioactive apatite could synergistically increase the expressions of integrin-related gene(ITGα5β1)and osteoblastic genes(Col-I and OCN),and thus promote osteoblast growth.In addition,owing to the anti-bone resorption property of Sr^(2+),the coating could effectively inhibit osteoclast differentiation and proliferation.In a word,the prepared samples not only promoted osteogenesis but also inhibited osteoclastogenesis.The in vivo experiment via a rabbit model found that the bionic structured surface provided the pore for new bone ingrowth,which was beneficial to the mechanical interlocking between the implant and bone.Moreover,the bionic structure and bioactive SrHA coating had a synergistic effect on promoting bone formation,osseointegration,and bone-implant bonding strength.This study therefore presented a new strategy to fabricate bio-functionalized Ti-based implants for potential application in orthopedics field.

Hierarchical Microphase Behaviors of Chiral Block Copolymers under Kinetic and Thermodynamic Control

Chiral superstructures in confined spaces are subtly affected by the complex interplay among various noncovalent interactions,details of which are still in adequately understood.Herein,we report the threedimensional confined assembly of the chiral block copolymers of polystyrene-block-poly(D-lactide)andits enantiomer in emulsion droplets and demonstrate unprecedented successive microphase transformations from single helices to double helices with inverted helicity,and then to twisted cylinders in the constructedcolloidal particles.Theabovehierarchical structural transformations of chiral microphases are kinetically dependent and can further transform into thermodynamically stable achiral cylinders with saddle-shaped topology upon solvent annealing.The formation and subsequent structural transformations as well as thefinal degeneration of chiral architectures provide guidance to understand the chiral evolution at different length scales within spherical confined space and to fabricate biomimetic systems.

Porous Nickel-Molybdenum Phosphide Alloy Electrodes for Alkaline Hydrogen Evolution Reaction at the High-Current Density

Alkaline water electrolysis is a practical route for large-scale green hydrogen production to assist decarbonization,whereby carbon dioxide emissions are limited.However,the use of this process in hydrogen evolution reaction(HER)is hampered by the alkaline solution,which leads to slow H_(2)O dissociation kinetics,especially when nickel–molybdenum(NiMo)alloy catalysts are utilized;thus,an improvement of this approach for effective HER activity is desirable.In this work,a porous phosphide NiMo-based(NiMoP)alloy electrode catalyst was engineered using a multistep electrodeposition method.Various experiments,combined with theoretical calculations,confirmed that the phosphide incorporation in the NiMo alloys promoted alkaline HER performance at a high current density of 1000 mA cm^(−2)with the potential−0.191 V.The evaluation of the effect of electrodeposition current density on HER performance revealed that the P content indeed positively impacted the accompanying alkaline HER performance,attributable to phosphide contribution in the electron reconstruction.Density functional theory(DFT)calculations demonstrated that the P atom promoted the loss of Mo electrons and hindered Ni from gaining electrons.This charge reconstruction allowed the optimization of the H^(*)adsorption,contributing to a stronger H_(2)O adsorption and encouraging H-OH^(*)bond breakage.Our current approach may provide the possibility of designing high-performance alkaline HER electrodes at high current density.