An Iterative Method for Split Variational Inclusion Problem and Split Fixed Point Problem for Averaged Mappings

In this paper, we use resolvent operator technology to construct a viscosity approximate algorithm to approximate a common solution of split variational inclusion problem and split fixed point problem for an averaged mapping in real Hilbert spaces. Further, we prove that the sequences generated by the proposed iterative method converge strongly to a common solution of split variational inclusion problem and split fixed point problem for averaged mappings which is also the unique solution of the variational inequality problem. The results presented here improve and extend the corresponding results in this area.

Regulating local coordination environment of Mg-Co single atom catalyst for improved direct methanol fuel cell cathode

Fuel cells operated with a reformate fuel such as methanol are promising power systems for portable electronic devices due to their high safety,high energy density and low pollutant emissions.However,several critical issues including methanol crossover effect,CO-tolerance electrode and efficient oxygen reduction electrocatalyst with low or non-platinum usage have to be addressed before the direct methanol fuel cells(DMFCs)become commercially available for industrial application.Here,we report a highly active and selective Mg-Co dualsite oxygen reduction reaction(ORR)single atom catalyst(SAC)with porous N-doped carbon as the substrate.The catalyst exhibits a commercial Pt/C-comparable half-wave potential of 0.806 V(versus the reversible hydrogen electrode)in acid media with good stability.Furthermore,practical DMFCs test achieves a peak power density of over 200 m W cm^(-2)that far exceeds that of commercial Pt/C counterpart(82 m W cm^(-2)).Particularly,the Mg-Co DMFC system runs over 10 h with negligible current loss under 10 M concentration methanol work condition.Experimental results and theoretical calculations reveal that the N atom coordinated by Mg and Co atom exhibits an unconventional d-band-ditto localized p-band and can promote the dissociation of the key intermediate*OOH into*O and*OH,which accounts for the near unity selective 4e-ORR reaction pathway and enhanced ORR activity.In contrast,the N atom in SAC–Co remains inert in the absorption and desorption of*OOH and*OH.This local coordination environment regulation strategy around active sites may promote rational design of high-performance and durable fuel cell cathode electrocatalysts.

Origin of Bismuth-Rich Strategy in Bismuth Oxyhalide Photocatalysts

Recently,the bismuth-rich strategy via increasing the bismuth content has been becoming one of the most appealing approaches to improve the photocatalytic performance of bismuth oxyhalides.However,insights into the mechanism behind the encouraging experiments are missing.Herein,we report the results of the theory-led comprehensive picture of bismuth-rich strategy in bismuth oxyhalide photocatalysts,selecting Bi_(5)O_(7)X(X=F,Cl,Br,I)as a prototype.First-principle calculations revealed that the strategy enables good n-type conductivity,large intrinsic internal electric field,high photoreduction ability and outstanding harvest of visible light,and particularly ranked the intrinsic activity of this family:Bi_(5)O_(7)F>Bi_(5)O_(7)I>Bi_(5)O_(7)Br>Bi_(5)O_(7)Cl.Designed experiments confirmed the theoretical predictions,and together,these results are expected to aid future development of advanced photocatalysts.

Isotype Heterojunction‑Boosted CO_(2) Photoreduction to CO

Photocatalytic conversion of CO_(2) to high-value products plays a crucial role in the global pursuit of carbon–neutral economy.Junction photocatalysts,such as the isotype heterojunctions,offer an ideal paradigm to navigate the photocatalytic CO_(2) reduction reaction(CRR).Herein,we elucidate the behaviors of isotype heterojunctions toward photocatalytic CRR over a representative photocatalyst,g-C_(3)N_(4).Impressively,the isotype heterojunctions possess a significantly higher efficiency for the spatial separation and transfer of photogenerated carriers than the single components.Along with the intrinsically outstanding stability,the isotype heterojunctions exhibit an exceptional and stable activity toward the CO_(2) photoreduction to CO.More importantly,by combining quantitative in situ technique with the first-principles modeling,we elucidate that the enhanced photoinduced charge dynamics promotes the production of key intermediates and thus the whole reaction kinetics.

Engineering nanointerface of molybdenum-based heterostructures to boost the electrocatalytic hydrogen evolution reaction

Rational heterostructure-design in electrocatalysts represents a promising approach toward high performance in the electrocatalytic hydrogen evolution reaction(HER).In specific,optimizing the H adsorption behavior at the surface/interface of heterostructure is of key importance to improve the catalytic performance.Herein,we demonstrate the construction of a heterostructure from a well-defined oxygenbridged Co/Mo heterometallic zeolitic imidazolate framework(MOZ) as an efficient electrocatalyst for HER.The optimized hybrid exhibits high catalytic activity and stability in electrolytes with a wide pH range.Detailed XPS,XAS and theoretical studies reveal that the regulation of metal species can tailor the lattice of Mo_(2)C within the hybrid and induce the formation of defect sites,which could not only induce surface charge transfer between the atoms and provide an additional active site,but also affect the H adsorption behavior at the interface of a heterostructure.This work provides an effective strategy to design a heterostructure with tailored active sites for energy conversion.

池沸腾加热器换热优化设计——基于Boltzmann方法研究并选取加热器最优参数

本文采用了相变格子Boltzmann模型研究加热器高度、长度、表面润湿性和表面结构对池沸腾换热性能的影响。我们发现加热器高度较低时汽液相变速度更大,因此加热器高度越低热流密度越大。另一方面,加热器长度越短,换热性能越好;其次,在低过热度下全疏水加热器换热性能最好,而在高过热度下全亲水换热器性能则更好;最后,我们还研究了加热器表面微结构的影响,发现锥形表面加热器的换热性能要优于光滑表面加热器。

Bismuth clusters pinned on TiO_(2) porous nanowires boosting charge transfer for CO_(2) photoreduction to CH_(4)

Artificial photosynthesis in carbon dioxide(CO_(2))conversion into value-added chemicals attracts considerable attention but suffers from the low activity induced by sluggish separation of photogenerated carriers and the kinetic bottleneck-induced unsatisfied selectivity.Herein,we prepare a new-style Bi/TiO_(2) catalyst formed by pinning bismuth clusters on TiO_(2) nanowires through being confined by pores,which exhibits high activity and selectivity towards photocatalytic production of CH_(4) from CO_(2).Boosted charge transfer from TiO_(2) through Bi to the reactants is revealed via in situ X-ray photon spectroscopy and time-resolved photoluminescence(PL).Further,in situ Fourier transform infrared results confirm that Bi/TiO_(2) not only overcomes the multi-electron kinetics challenge of CO_(2) to CH_(4) via boosting charge transfer,but also facilitates proton production and transfer as well as the intermediates*CHO and*CH_(3)O generation,ultimately achieving the tandem catalysis towards methanation.Theoretical calculation also underlies that the more favorable reaction step from*CO to*CHO on Bi/TiO_(2) results in CH_(4) production with higher selectivity.Our work brings new insights into rational design of photocatalysts with high performance and the formation mechanism of CO_(2) to CH_(4) for solar energy storage in future.

A new insight into the promoting effects of transition metal phosphides in methanol electrooxidation

The construction of highly active catalysts for methanol oxidation reaction(MOR)is central to direct methanol fuel cells.Tremendous progress has been made in transition metal phosphides(TMPs)based catalysts.However,TMPs would be partially damaged and transformed into new substances(e.g.,Pt-M-P composite,where M represents a second transition metal)during Pt deposition process.This would pose a large obstacle to the cognition of the real promoting effects of TMPs in MOR.Herein,Co_(2)P co-catalysts(Pt-P/Co_(2)P@NPC,where NPC stands for N and P co-doped carbon)and Pt-Co-P composite catalysts(Pt-CoP/NPC)were controllably synthesized.Electrocatalysis tests show that the Pt-Co-P/NPC exhibits superior MOR activity as high as 1016 m A/mg_(Pt),significantly exceeding that of Pt-P/Co_(2)P@NPC(345 m A/mg_(Pt)).This result indicates that the promoting effect is ascribed primarily to the resultant Pt-Co-P composite,in sharply contrast to previous viewpoint that Co_(2)P itself improves the activity.Further mechanistic studies reveal that Pt-Co-P/NPC exhibits much stronger electron interaction and thus manifesting a remarkably weaker CO absorption than Pt-P/Co_(2)P@NPC and Pt/C.Moreover,Pt-Co-P is also more capable of producing oxygen-containing adsorbate and thus accelerating the removal of surface-bonded CO^(*),ultimately boosting the MOR performance.

N_(2)photofixation promoted by in situ photoinduced dynamic iodine vacancies at step edge in Bi_(5)O_(7)I nanotubes

Heterogeneous photosynthesis is a promising route for sustainable ammonia production,which can utilize renewable energy and water as the hydrogen source under ambient condition.In this study,a series of Bi_(5)O_(7)I(BOI)nanosheets and nanotubes are synthesized,the surface tensile strain is formed by curling the nanosheets into nanotubes to tune the concentration and location of dynamic vacancies.Scanning transmission electron microscopy(STEM)with spherical aberration correction confirms the presence of intrinsic areal defects on the surface of the BOI nanotube resulted from surface tensile strain.The presence of areal defects lowers the formation energy of I vacancies(IV)at step edge site,thus the IV with higher concentration would be favorably generated under visible light.Rapid scan in situ Fourier transform infrared(FT-IR)analysis in the aqueous media reveals that the IV promotes photocatalytic N_(2) activation and reduction,proceeds through an associative alternating mechanism.Specially,after turning off the light,the surface vacancy sites can be reoccupied by I−ions,which enables the protection and regeneration of photocatalyst surface in an aerobic and dark environment.This work provides an innovative strategy to tune concentration and location of dynamic surface vacancies on photocatalysts by building surface tensile strain for advancing sustainable ammonia production.

Combined Photoredox Catalysis for Value-Added Conversion of Contaminants at Spatially Separated Dual Active Sites

As 2 indispensable counterparts in one catalysis system,the independent reduction and oxidation reactions require synergetic regulation for cooperatively promoting redox efficiency.Despite the current success in promoting the catalytic efficiency of half reduction or oxidation reactions,the lack of redox integration leads to low energy efficiency and unsatisfied catalytic performance.Here,we exploit an emerging photoredox catalysis system by combining the reactions of nitrate reduction for ammonia synthesis and formaldehyde oxidation for formic acid production,in which superior photoredox efficiency is achieved on the spatially separated dual active sites of Ba single atoms and Ti^(3+).High catalytic redox rates are accomplished for respective ammonia synthesis(31.99±0.79 mmol gcat^(−1) h^(−1))and formic acid production(54.11±1.12 mmol gcat^(−1) h^(−1)),reaching a photoredox apparent quantum efficiency of 10.3%.Then,the critical roles of the spatially separated dual active sites are revealed,where Ba single atoms as the oxidation site using h+and Ti3+as the reduction site using e−are identified,respectively.The efficient photoredox conversion of contaminants is accomplished with environmental importance and competitive economic value.This study also represents a new opportunity to upgrade the conventional half photocatalysis into the complete paradigm for sustainable solar energy utilization.

α2,3-Sialylation with Fucosylation Associated with More Severe Anti-MDA5 Positive Dermatomyositis Induced by Rapidly Progressive Interstitial Lung Disease

Dermatomyositis(DM)is a heterogeneous autoimmune disease associated with numerous myositis specific antibodies(MSAs)in which DM with anti-melanoma differentiation-associated gene 5-positive(MDA5+DM)is a unique subtype of DM with higher risk of developing varying degrees of Interstitial lung disease(ILD).Glycosylation is a complex posttranslational modification of proteins associated with many autoimmune diseases.However,the association of total plasma N-glycome(TPNG)and DM,especially MDA5+DM,is still unknown.TPNG of 94 DM patients and 168 controls were analyzed by mass spectrometry with in-house reliable quantitative method called Bionic Glycome method.Logistic regression with age and sex adjusted was used to reveal the aberrant glycosylation of DM and the association of TPNG and MDA5+DM with or without rapidly progressive ILD(RPILD).The elastic net model was used to evaluate performance of glycans in distinguishing RPLID from non-RPILD,and survival analysis was analyzed with N-glycoslyation score by Kaplan-Meier survival analysis.It was found that the plasma protein N-glycome in DM showed higher fucosylation and bisection,lower sialylation(α2,3-notα2,6-linked)and galactosylation than controls.In MDA5+DM,more severe disease condition was associated with decreased sialylation(specificallyα2,3-sialylation with fucosylation)while accompanying elevated H6N5S3 and H5N4FSx,decreased galactosylation and increased fucosylation and the complexity of N-glycans.Moreover,glycosylation traits have better discrimination ability to distinguish RPILD from non-RPILD with AUC 0.922 than clinical features and is MDA5-independent.Survival advantage accrued to MDA5+DM with lower N-glycosylation score(p=3e-04).Our study reveals the aberrant glycosylation of DM for the first time and indicated that glycosylation is associated with disease severity caused by ILD in MDA5+DM,which might be considered as the potential biomarker for early diagnosis of RPILD and survival evaluation of MDA5+DM.

Interfacial Engineering of NiFeP/NiFe-LDH Heterojunction for Efficient Overall Water Splitting

In consideration of application prospect of non-noble metallic materials catalysts,the study of exploring more highly effective electrocatalysts has been focused on by researchers.Herein,a novel strategy is employed to construct a heterojunction consisting of metal phosphide Ni_(x)Fe_(y)P and layered double hydroxide(LDH)with graphene oxide(GO)as conductive support.By adjusting the molar ratio of Ni to Fe,a series of heterojunctions with mixed valence state Fe^(δ+)/Fe^(3+)and Ni^(δ+)/Ni^(2+)(δis likely close to 0)redox couples are achieved and strong synergistic effects towards overall water splitting performance are found.The optimized catalyst with a Ni/Fe molar ratio of 0.72:0.33,namely Ni_(0.7)Fe_(0.3)P/LDH/GO,delivers ultra-low overpotentials for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)of 79 and 198 mV at the current density of 10 mA·cm^(-2),respectively.Furthermore,for overall water-splitting practical application,it only requires 1.526 V at 10 mA·cm^(-2)with robust stability,which is superior to most reported electrocatalysts.Experimental results demonstrate the im-proved electronic conductivity,enlarged electrochemically active area and accelerated kinetics together account for the enhanced performance.This work supplies new prospects for the promotion and application of such heterojunction electrocatalysts in overall water splitting.

Water-based lubrication of niobium nitride

Water-based lubrication has attracted wide attention as an oil-free lubrication method owing to its greener and cleaner lubrication means.However,due to operating in the water environment,most moving parts would inevitably suffer from abrasion,rusting,and aging problems.Developing a novel solid-water composite system with ultra-low friction and wear will open new possibilities for innovative lubrication material research and development.Here,we first revealed the water-based lubrication behavior of a high-hardness niobium nitride coating(NbN).In a three-phase contact environment(water,air,and NbN),oxidation and hydrolytic reactions of NbN result in the formation of"colloidal solutions",containing Nb_(2)O_(5)colloidal particles between the tribo-pairs.Utilizing the double electric layer repulsion and weak shear action of the"colloidal solution",NbN achieves ultra-low friction and wear;the corresponding values are as low as 0.058 and 1.79×10^(-10)mm^(3)·N^(-1)·m^(-1),respectively.In addition,other VB transition metal nitrides(VB TMNs)exhibit the same low friction feature as NbN in the three-phase contact environment;the friction coefficients are even lower than those in an oil-based environment.The water-based lubrication of VB TMNs provides a new reliable scheme for optimizing solid-water composite lubrication systems without additives and is expected to be applied in environments with high humidity or insufficient water coverage.