Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls

Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

基于TLR4 NF-κB通路-神经相关因子探究依达拉奉对急性脑梗死患者炎症反应与神经损伤的保护机制

目的基于Toll样受体4(TLR4)核因子-κB(NF-κB)通路-神经相关因子探究依达拉奉对急性脑梗死(ACI)患者炎症反应与神经损伤的保护机制。方法选取2020-07—2023-07保定市第一中心医院收治的110例ACI患者,以随机数字表法分为观察组、对照组,各55例,对照组给予阿替普酶溶栓,观察组给予阿替普酶溶栓联合依达拉奉治疗。比较2组疗效、神经功能[美国国立卫生研究院卒中量表(NIHSS)评分、改良Rankin评分]、TLR4 NF-κB通路指标(TLR4、NF-κB)、神经损伤相关因子[神经元特异性烯醇化酶(NSE)、中枢神经特异性蛋白(S-100β)、脑源性神经营养因子(BDNF)]、TLR4 NF-κB通路相关炎症因子[白介素-1β(IL-1β)、超敏C反应蛋白(hs-CRP)、肿瘤坏死因子(TNF-α)、五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)]。结果观察组总有效率96.36%,高于对照组的83.64%(P<0.05)。治疗1、2周观察组NIHSS评分、改良Rankin评分均低于对照组(P<0.05),观察组TLR4、NF-κB均低于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后S-100β、NSE水平明显下降,BDNF水平明显升高,观察组S-100β、NSE水平均低于对照组,BDNF水平高于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均明显下降,观察组IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均低于对照组(P<0.05)。结论依达拉奉对ACI患者的疗效显著,有利于缓解炎症反应,改善神经损伤,其保护机制可能与TLR4 NF-κB通路调控神经损伤、炎症反应相关因子有关。

Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature

Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering.

双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质

使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料.

中药单体治疗脊髓损伤后神经炎症:核转录因子κB信号通路的作用

背景:基于核转录因子κB通路探究神经炎症的靶向治疗越来越值得探究,中药靶点多、范围广、机制丰富及不良反应少等优点在治疗各类疾病时都具有十分巨大的潜力。目的:基于核转录因子κB信号通路,对近年研究中出现的山奈酚、红花黄、汉黄芩苷及雷公藤甲素等中药单体治疗脊髓损伤后神经炎症的研究进展进行系统的阐述与归纳。方法:以“脊髓损伤,炎症,抗炎,中药单体,单体化合物,NF-κB信号通路,黄酮,糖苷,酚类,酯类,生物碱”为检索词在中国知网数据库中进行检索;以“Spinal cord injury,inflammation,anti-inflammatory,traditional Chinese medicine monomer,monomeric compound,NF-κB signaling pathway,flavonoids,glycosides,phenols,esters,alkaloids”为检索词在PubMed数据库中进行检索,最终共纳入67篇文献进行综述分析。结果与结论:①核转录因子κB信号通路在神经系统中的作用复杂多样,能够调控中性粒细胞、小胶质细胞、星形胶质细胞和巨噬细胞等,介导损伤后炎症的发生与发展;②中药单体如汉黄芩苷对核转录因子κB抑制蛋白的降解、红花黄素对核转录因子κB信号通路磷酸化过程的抑制、山奈酚对核转录因子κB信号通路p65核易位的抑制等作用可以降低炎症反应对机体造成的影响,从而促进神经功能恢复;③核转录因子κB信号通路在损伤早期能够促进炎症反应和免疫细胞迁移活化,在损伤中后期能够促进损伤部位的修复和纤维化的发生等,适当的激活核转录因子κB信号通路具有促进炎症因子的释放、提高细胞的抗氧化能力及促进免疫细胞的活化等能力,但过度激活的核转录因子κB信号通路则容易导致慢性炎症的发生和持续、细胞凋亡受到抑制等;④未来的研究可以进一步探索如何准确调控核转录因子κB信号通路的活化水平、如何实现对神经系统炎症和损伤的精准干预展开,也可围绕中药单体的制备及中药单体对信号通路的作用机制展开,以期为神经系统疾病的康复和功能恢复提供更有效的治疗策略。

INTERFACE BEHAVIOR AND DECAY RATES OF COMPRESSIBLE NAVIER-STOKES SYSTEM WITH DENSITY-DEPENDENT VISCOSITY AND A VACUUM

In this paper,we study the one-dimensional motion of viscous gas near a vacuum,with the gas connecting to a vacuum state with a jump in density.The interface behavior,the pointwise decay rates of the density function and the expanding rates of the interface are obtained with the viscosity coefficientμ(ρ)=ρ^(α)for any 0<α<1;this includes the timeweighted boundedness from below and above.The smoothness of the solution is discussed.Moreover,we construct a class of self-similar classical solutions which exhibit some interesting properties,such as optimal estimates.The present paper extends the results in[Luo T,Xin Z P,Yang T.SIAM J Math Anal,2000,31(6):1175-1191]to the jump boundary conditions case with density-dependent viscosity.

A Review of Contact Electrification at Diversified Interfaces and Related Applications on Triboelectric Nanogenerator

The triboelectric nanogenerator(TENG)can effectively collect energy based on contact electrification(CE)at diverse interfaces,including solid–solid,liquid–solid,liquid–liquid,gas–solid,and gas–liquid.This enables energy harvesting from sources such as water,wind,and sound.In this review,we provide an overview of the coexistence of electron and ion transfer in the CE process.We elucidate the diverse dominant mechanisms observed at different interfaces and emphasize the interconnectedness and complementary nature of interface studies.The review also offers a comprehensive summary of the factors influencing charge transfer and the advancements in interfacial modification techniques.Additionally,we highlight the wide range of applications stemming from the distinctive characteristics of charge transfer at various interfaces.Finally,this review elucidates the future opportunities and challenges that interface CE may encounter.We anticipate that this review can offer valuable insights for future research on interface CE and facilitate the continued development and industrialization of TENG.

Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces

Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.

Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model

Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as control.The shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after operation.The Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to failure.Gross observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture groups.In the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks postoperatively.The collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous enthesis.In vivo degradation of the magnesium alloy wire was completed within 12 weeks.The results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair.

Unraveling the Fundamental Mechanism of Interface Conductive Network Influence on the Fast‑Charging Performance of SiO‑Based Anode for Lithium‑Ion Batteries

Progress in the fast charging of high-capacity silicon monoxide(SiO)-based anode is currently hindered by insufficient conductivity and notable volume expansion.The construction of an interface conductive network effectively addresses the aforementioned problems;however,the impact of its quality on lithium-ion transfer and structure durability is yet to be explored.Herein,the influence of an interface conductive network on ionic transport and mechanical stability under fast charging is explored for the first time.2D modeling simulation and Cryo-transmission electron microscopy precisely reveal the mitigation of interface polarization owing to a higher fraction of conductive inorganic species formation in bilayer solid electrolyte interphase is mainly responsible for a linear decrease in ionic diffusion energy barrier.Furthermore,atomic force microscopy and Raman shift exhibit substantial stress dissipation generated by a complete conductive network,which is critical to the linear reduction of electrode residual stress.This study provides insights into the rational design of optimized interface SiO-based anodes with reinforced fast-charging performance.

Numerical parametric study on the influence of location and inclination of large-scale asperities on the shear strength of concreterock interfaces of small buttress dams

When assessing the sliding stability of a concrete dam,the influence of large-scale asperities in the sliding plane is often ignored due to limitations of the analytical rigid body assessment methods provided by current dam assessment guidelines.However,these asperities can potentially improve the load capacity of a concrete dam in terms of sliding stability.Although their influence in a sliding plane has been thoroughly studied for direct shear,their influence under eccentric loading,as in the case of dams,is unknown.This paper presents the results of a parametric study that used finite element analysis(FEA)to investigate the influence of large-scale asperities on the load capacity of small buttress dams.By varying the inclination and location of an asperity located in the concrete-rock interface along with the strength of the rock foundation material,transitions between different failure modes and correlations between the load capacity and the varied parameters were observed.The results indicated that the inclination of the asperity had a significant impact on the failure mode.When the inclinationwas 30and greater,interlocking occurred between the dam and foundation and the governing failure modes were either rupture of the dam body or asperity.When the asperity inclination was significant enough to provide interlocking,the load capacity of the dam was impacted by the strength of the rock in the foundation through influencing the load capacity of the asperity.The location of the asperity along the concrete-rock interface did not affect the failure mode,except for when the asperity was located at the toe of the dam,but had an influence on the load capacity when the failure occurred by rupture of the buttress or by sliding.By accounting for a single large-scale asperity in the concrete-rock interface of the analysed dam,a horizontal load capacity increase of 30%e160%was obtained,depending on the inclination and location of the asperity and the strength of the foundation material.

Construction of Dynamic Alloy Interfaces for Uniform Li Deposition in Li-Metal Batteries

It is well accepted that a lithiophilic interface can effectively regulate Li deposition behaviors,but the influence of the lithiophilic interface is gradually diminished upon continuous Li deposition that completely isolates Li from the lithiophilic metals.Herein,we perform in-depth studies on the creation of dynamic alloy interfaces upon Li deposition,arising from the exceptionally high diffusion coefficient of Hg in the amalgam solid solution.As a comparison,other metals such as Au,Ag,and Zn have typical diffusion coefficients of 10-20 orders of magnitude lower than that of Hg in the similar solid solution phases.This difference induces compact Li deposition pattern with an amalgam substrate even with a high areal capacity of 55 mAh cm^(-2).This finding provides new insight into the rational design of Li anode substrate for the stable cycling of Li metal batteries.

Plasma-assisted aerogel interface engineering enables uniform Zn^(2+)flux and fast desolvation kinetics toward zinc metal batteries

The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal batteries.To address these issues,a plasmaassisted aerogel(PAG)interface engineering was proposed as efficient ion transport modulator that can simultaneously regulate uniform Zn^(2+)flux and desolvation behavior during battery operation.The PAG with ordered mesopores acted as an ion sieve to homogenize Zn deposition and accelerate Zn^(2+)flux,which is favorable for corrosion resistance and dendrite suppression.Importantly,the plasma-assisted aerogel with abundant hydrophilic groups can facilitate the desolvation kinetics of Zn^(2+)due to the multiple hydrogen-bonding interaction with the activated water molecules,thus accelerating the Zn^(2+)migration kinetics.Consequently,the Zn/Zn cell assembled with PAG-modified separator demonstrates stable plating and stripping behavior(over 1400 h at 1 mA cm^(-2))and high Coulombic efficiency(99.8%at1 mA cm^(-2)after 1100 cycles),and the Zn‖MnO_(2)full cell shows excellent long-term cycling stability and maintains a high capacity of 154.9 mA h g^(-1)after 1000 cycles at 1 A g^(-1).This study provides a feasible approach for the large-scale fabrication of aerogel functionalized separators to realize ultra-stable Zn metal batteries.

基于“微生物-肠-脑轴”探讨补肾通腑方对APP/PS1小鼠肠道菌群及LPS/TLR4/NF-κB通路的影响

目的探讨补肾通腑方调控肠道菌群,改善阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠学习记忆能力的作用机制。方法以APP/PS1小鼠为研究对象,给予补肾通腑方治疗8周,采用Morris水迷宫法观察小鼠空间学习记忆能力变化;16S rDNA检测小鼠肠道菌群丰度、多样性变化;HE染色观察海马病理形态学变化;免疫荧光检测海马区小胶质细胞活化情况;Western blot检测TLR4、NF-κB、IL-6等炎症因子表达。结果与模型组相比,补肾通腑方可以缩短AD模型小鼠逃避潜伏期、游泳路径,增加跨越平台次数(P<0.05),提升肠道菌群多样性,调节肠道菌群丰度,促进海马神经元细胞损伤修复,降低iNOS/Iba1共表达,提高Arg1/Iba1共表达(P<0.01),促进小胶质细胞从M1型向M2型转化,下调TLR4、NF-κB、IL-6等促炎因子的表达。结论补肾通腑方改善AD模型小鼠学习记忆能力的作用机制可能与调节肠道菌群介导的LPS/TLR4/NF-κB通路,从而抑制促炎型小胶质细胞活化、减轻中枢神经系统炎症、改善海马区神经元细胞损伤有关。

Effect of Interface Form on Creep Failure and Life of Dissimilar Metal Welds Involving Nickel-Based Weld Metal and Ferritic Base Metal

For dissimilar metal welds(DMWs)involving nickel-based weld metal(WM)and ferritic heat resistant steel base metal(BM)in power plants,there must be an interface between WM and BM,and this interface suffers mechanical and microstructure mismatches and is often the rupture location of premature failure.In this study,a new form of WM/BM interface form,namely double Y-type interface was designed for the DMWs.Creep behaviors and life of DMWs containing double Y-type interface and conventional I-type interface were compared by finite element analysis and creep tests,and creep failure mechanisms were investigated by stress-strain analysis and microstructure characterization.By applying double Y-type interface instead of conventional I-type interface,failure location of DMW could be shifted from the WM/ferritic heat-affected zone(HAZ)interface into the ferritic HAZ or even the ferritic BM,and the failure mode change improved the creep life of DMW.The interface premature failure of I-type interface DMW was related to the coupling effect of microstructure degradation,stress and strain concentrations,and oxide notch on the WM/HAZ interface.The creep failure of double Y-type interface DMW was the result of Type IV fracture due to the creep voids and micro-cracks on fine-grain boundaries in HAZ,which was a result of the matrix softening of HAZ and lack of precipitate pinning at fine-grain boundaries.The double Y-type interface form separated the stress and strain concentrations in DMW from the WM/HAZ interface,preventing the trigger effect of oxide notch on interface failure and inhibiting the interfacial microstructure cracking.It is a novel scheme to prolong creep life and enhance reliability of DMW,by means of optimizing the interface form,decoupling the damage factors from WM/HAZ interface,and then changing the failure mechanism and shifting the failure location.

葫芦素B改善脂多糖诱导C2C12肌管萎缩作用机制

目的 探讨葫芦素B(Cucurbitacin B,CuB)对LPS诱导的C2C12肌管萎缩和C57BL/6小鼠骨骼肌萎缩的影响。方法 采用蛋白免疫印迹法检测蛋白表达水平,苏木精-伊红染色法观察细胞形态变化,通过测量小鼠握力以及腓肠肌和胫骨前肌质量评估骨骼肌萎缩程度。结果 蛋白免疫印迹试验表明,LPS能够诱导C2C12肌管萎缩(P<0.01),而经葫芦素B(0.3~3.0μmol/L)处理后可促进肌管分化相关蛋白(MyHC)及肌肉合成相关蛋白的表达,减少促炎因子(IL-1β、COX-2)释放(P<0.001)。苏木精-伊红染色试验结果从形态学角度证实了葫芦素B能有效改善LPS刺激下的肌管萎缩。此外,动物试验显示,LPS可导致C57BL/6小鼠握力以及腓肠肌与胫骨前肌质量显著下降,而经葫芦素B治疗后症状有所改善(P<0.05)。结论 葫芦素B在治疗骨骼肌萎缩方面具有潜在应用价值,为开发天然药物来源的先导化合物提供了理论依据,并为炎症诱导的骨骼肌萎缩的治疗开辟了新思路。

Recent Advances in Nanoengineering of Electrode-Electrolyte Interfaces to Realize High-Performance Li-Ion Batteries

A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li-ion batteries,as facile ionic transport is required.Intriguing research and development have recently been conducted to form a stable interface between the electrode and electrolyte.Therefore,it is essential to investigate emerging knowledge and contextualize it.The nanoengineering of the electrode-electrolyte interface has been actively researched at the electrode/electrolyte and interphase levels.This review presents and summarizes some recent advances aimed at nanoengineering approaches to build a more stable electrode-electrolyte interface and assess the impact of each approach adopted.Furthermore,future perspectives on the feasibility and practicality of each approach will also be reviewed in detail.Finally,this review aids in projecting a more sustainable research pathway for a nanoengineered interphase design between electrode and electrolyte,which is pivotal for high-performance,thermally stable Li-ion batteries.

Ethylenediamine tetramethylenephosphonic acid boosting the electrocatalytic interface construct and proton transfer for high-temperature polymer electrolyte membrane fuel cells

High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) show excellent application prospects due to its enhanced tolerance of hydrogen impurity.However,the sluggish electrode kinetics caused by its inefficient electrocatalytic interface and proton transfer severely restricts its performance.To overcome the sluggish electrode kinetics,the ethylenediamine tetramethylenephosphonic acid(EDTMPA) was successfully incorporated into the catalysts layer to regulate the phosphoric acid (PA) distribution to boost the electrocatalytic reaction interface and proton transfer,thus increasing the output power and stability of HT-PEMFCs.The hydrophilic H_(2)PO_(4)^(-) and electron donor N atom of EDTMPA could efficiently decrease the absorption of PA on the catalyst surface and facilitate proton transportation in the membrane electrode,as demonstrated by our experiments.The fuel cell assembled with the prepared membrane electrode shows a high reactivity of 1175 mW cm^(-2)and excellent stability,which is much better than the past reference report.The results of this work provide new insights into the utilization of small molecules with phosphate groups to enhance phosphate tolerance and proton conduction,and there is also a further improvement in the reactivity,durability,and utilization of the electrocatalysts in HT-PEMFCs.

Preparation and interface state of phosphate tailing-based geopolymers

The long-term storage of phosphate tailings will occupy a large amount of land,pollute soil and groundwater,thus,it is crucial to achieve the harmless disposal of phosphate tailings.In this study,high-performance geopolymers with compressive strength of 38.8 MPa were prepared by using phosphate tailings as the main raw material,fly ash as the active silicon-aluminum material,and water glass as the alkaline activator.The solid content of phosphate tailings and fly ash was 60% and 40%,respectively,and the water-cement ratio was 0.22.The results of XRD,FTIR,SEM-EDS and XPS show that the reactivity of phosphate tailings with alkaline activator is weak,and the silicon-aluminum material can react with alkaline activator to form zeolite and gel,and encapsulate/cover the phosphate tailings to form a dense phosphate tailings-based geopolymer.During the formation of geopolymers,part of the aluminum-oxygen tetrahedron replaced the silicon-oxygen tetrahedron,causing the polycondensation reaction between geopolymers and increasing the strength of geopolymers.The leaching toxicity test results show that the geopolymer has a good solid sealing effect on heavy metal ions.The preparation of geopolymer from phosphate tailings is an important way to alleviate the storage pressure and realize the resource utilization of phosphate tailings.