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Journal of Materials Science & technology 2022年第3期98卷 205-211页

作者： Yunwei Liu Zelin chen Chang Liu Jinfeng Zhang Wenbin hu Yida Deng tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300372China State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China

We have developed an efficient strategy to synthesize an active and durable electrocatalyst of Pd hydride nanocubes(NCs).Instead of the traditional chemical method,the Pdh_(0.43)NCs are firstly prepared via a hydrogen diffusion procedure,followed by hydrothermal synthesis of an amorphous CuO layer encapsulating the Pdh_(0.43)NCs to prevent the hydrogen atoms from *** lattice expansion is demonstrated playing a pivotal role in the enhancement of their oxygen reduction reaction(ORR)activity and *** obtained Pdh_(0.43)@CuO NCs catalysts exhibit an ORR mass activity of 0.18 A mg^(−1) at 0.90 V versus reversible hydrogen electrode in an alkaline medium,which is about five times higher than that of commercial Pt/*** durability tests show that there is only a 32 mV decay in halfwave potential even after 10,000 potential cycles,indicating the excellent stability of Pdh_(0.43)@CuO *** functional theory(DFt)calculations also indicate that,compared to Pd,Pdh_(0.43)has a lower limiting barrier to form Oh−during the ORR *** present study illustrates the importance of lattice expansion caused by hydrogen and offers an available strategy to design highly efficient and durable Pdbased electrocatalysts for alkaline fuel cells.

关键词： Lattice expansion Pd hydride Amorphous CuO Elecrocatalysis Oxygen reduction reaction

Metal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction

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Journal of Energy Chemistry 2021年第9期30卷 546-555页

作者： Ziming Zhao Yu Long Sha Luo Yutong Luo Ming chen Jiantai Ma State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000GansuChina

As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR electrocatalysts is far from enough and a systematic research is needed to gain a better improvement. this article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a simple and feasible method, and used as a metal-free catalyst for electrocatalytic NRR. Experiment result and density functional theory(DFt) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(hER) at the same time. In addition, the larger specific surface area also makes more active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. the electrocatalyst shows an excellent catalytic activity for NRR in 0.1 M hCl, including Faradaic efficiency of 10.96%, Nh_(3) yields of 17.85 lg h^(-1) mg_(cat)^(-1)., and good stability(over 20 h).

关键词： 2D C_(3)N_(4)-NV Larger specific surface area Nitrogen vacancy Electrocatalyst NRR

Progress in transdermal drug delivery systems for cancer therapy

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Nano Research 2020年第7期13卷 1810-1824页

作者： tianyue Jiang Guo Xu Guojun chen Yu Zheng Bingfang he Zhen Gu School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China Department of Bioengineering University of CaliforniaLos AngelesLos AngelesCA 90095USA Jonsson Comprehensive Cancer Center and California NanoSystems Institute University of CaliforniaLos AngelesLos AngelesCA 90095USA

transdermal drug delivery is an appealing option except for oral and hypodermic *** the advancement of skin penetration strategies,various anticancer therapeutics ranging from liphilic small-molecule drugs to hydrophilic biomacromolecules,can be administered transdermally,offering an optional regimen to treat skin *** addition,the activation of the skin immune systems can also assist the treatment of distal *** approaches on enhancing the transdermal delivery efficacy of anticancer drugs are summarized in this *** also survey recent advances in micro-and nanotechnology-based transdermal formulations for cancer treatment,such as chemotherapy,gene therapy,immunotherapy,phototherapy and combination *** penetration enhancers,materials,formulations and their hypothesized mechanisms for transdermal delivery are *** and limitations regarding the state-of-the-art transdermal delivery technologies,as well as future perspective are also discussed.

关键词： drug delivery transdermal delivery cancer therapy chemotherapy immunotherapy combination therapy

Preparation and property of self-sealed plasma electrolytic oxide coating on magnesium alloy

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International Journal of Minerals,Metallurgy and Materials 2023年第5期30卷 959-969页

作者： chen Ma Dong Wang Jinyu Liu Ning Peng Wei Shang Yuqing Wen Guangxi Key Laboratory of Electrochemical and Magnetochemical Function Materials College of Chemistry and BioengineeringGuilin University of TechnologyGuilin 541004China

Plasma electrochemical oxidation (PEO) is a surface modification technology to form ceramic coatings on magnesium alloys however,its application is limited due to its *** work reports a novel preparation of in-situ sealing of PEO coatings by four-layer voltage and sol *** morphology and structure were characterized by scanning electron microscopy (SEM),energy dispersive X-ray spectroscopy (EDS),and X-ray diffractometer (XRD).Image-Pro Plus 6.0 was used to determine the porosity of the coating,which was decreased from 8.53%to 0.51%.Simultaneously,the coating thickness was increased by a factor of *** anti-corrosion performance of each sample was evaluated using electrochemical tests,and the findings revealed that the corrosion current density of coatings (i_(corr)) of the samples were lowered from 9.152×10^(-2) to 6.152×10^(-4) mA·cm^(-2),and the total resistance (R_(t)) of the samples were enhanced from 2.19×10^(4) to 2.33×10^(5)Ω·cm^(2).the salt spray test used to simulate the actual environment showed that corrosion points appeared on the surface of the coating only at the 336 *** addition,the mechanism of PEO self-sealing behavior was described in this article.

关键词： magnesium alloy in-situ sealing plasma electrolytic oxidation corrosion resistance

Additive manufacturing of copper-stainless steel hybrid components using laser-aided directed energy deposition

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Journal of Materials Science & technology 2021年第21期80卷 100-116页

作者： Xinchang Zhang tan Pan Yitao chen Lan Li Yimlu Zhang Frank Liou Department of Mechanical&Aerospace Engineering Missouri University of Science and TechnologyRollaMO65409USA

Combining dissimilar materials in a single component is an effective solution to integrate diverse material properties into a single ***-stainless steel hybrid components are attracting more and more attention since the high thermal conductivity of copper can greatly enhance the thermal performance of stainless steel,which benefits its applications in many ***,direct joining of copper and stainless steel such as SS316 L is challenging since they preserve significant dissimilarities in physical,chemical,and thermo-mechanical *** paper aims to fabricate well-bonded copper-SS316 L hybrid parts using a laser-aided directed energy deposition(DED) process.A nickel-based alloy Deloro22(D22) is introduced between copper and SS316 L to address the detrimental issues in copper-SS316 L direct *** this technique,defect-free interfaces are achieved at both the D22-SS316 L and copper-D22 transition *** testing of Cu-D22-SS316 L and D22-SS316 L hybrid parts shows the fracture occurs at pure copper and SS316 L region,respectively,indicating an excellent bonding at the *** in the building direction,a transition of grain structure is observed.A significant diffusion zone is obtained at both the D22-SS316 L and the Cu-D22 *** large diffusion distance results in a smooth variation in microhardness over the dissimilar *** microhardness increases from SS316 L to D22 with the highest value of 240 hV and then decreases from D22 to Cu with the lowest value of 63 ± 4 *** of thermophysical properties of the Cu-D22-SS316 L system indicates there is a ~300 % increase in thermal diffusivity and a ~200 % increase in thermal conductivity when compared to pure SS316 *** significant increase in thermal diffusivity and conductivity validates the enhanced thermal performance of SS316 L when it is joined with pure copper.

关键词： Additive manufacturing Directed energy deposition Multi-material components Dissimilar materials Copper Stainless steel

Phosphorylated cellulose nanofibers establishing reliable ion-sieving barriers for durable lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第5期92卷 619-628页

作者： Zihao Li Pengsen Qian hongyang Li he Xiao Jun chen Gaoran Li School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina National Forestry and Grassland Administration Key Laboratory of Plant Fiber Functional Materials Fuzhou 350108FujianChina

the shuttle effect is among the most characteristic and formidable challenges in the pursuit of high-performance lithium-sulfur(Li-S)***,phosphorylated cellulose nanofibers(pCNF)are intentionally engineered to establish an ion-sieving barrier against polysulfide shuttling and thereby improve battery *** phosphorylation,involving the grafting of phosphate groups onto the cellulose backbone,imparts an exceptional electronegativity that repels the polysulfide anions from penetrating through the ***,the electrolyte wettability and Li^(+)transfer can be significantly promoted by the polar nature of pCNF and the facile Li^(+)*** such,rational ion management is realized,contributing to enhanced reversibility in both sulfur and lithium *** a result,Li-S cells equipped with the self-standing pCNF separator demonstrate outstanding long-term cyclability with a minimum fading rate of 0.013%per cycle over 1000 cycles at 1 C,and a decent areal capacity of 5.37 mA h cm^(-2) even under elevated sulfur loading of 5.0 mg cm^(-2) and limited electrolyte of 6.0 mL g^(-1).this work provides a facile and effective pathway toward the well-tamed shuttle effect and highly durable Li-S batteries.

关键词： Lithium-sulfur batteries Cellulose Phosphorylation Ion-sieving Shuttle effect

high strain rate compressive strength behavior of cemented paste backfill using split hopkinson pressure bar

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International Journal of Mining Science and technology 2021年第3期31卷 387-399页

作者： Xin chen Xiuzhi Shi Jian Zhou Enming Li Peiyong Qiu Yonggang Gou School of Resources and Safety Engineering Central South UniversityChangsha 410083China Research Institute on Mines and Environment Department of CivilGeological and Mining EngineeringÉcole Polytechnique de MontréalMontréal H3C 3A7Canada

the stability of cemented paste backfill(CPB)is threatened by dynamic disturbance,but the conventional low strain rate laboratory pressure test has difficulty achieving this research ***,a split hopkinson pressure bar(ShPB)was utilized to investigate the high strain rate compressive behavior of CPB with dynamic loads of 0.4,0.8,and 1.2 *** the failure modes were determined by macro and micro *** with different cement-to-tailings ratios,solid mass concentrations,and curing ages was prepared to conduct the ShPB *** results showed that increasing the cement content,tailings content,and curing age can improve the dynamic compressive strength and elastic *** an impact load,a higher strain rate can lead to larger increasing times of the dynamic compressive strength when compared with static *** the dynamic compressive strength of CPB has an exponential correlation with the strain *** macroscopic failure modes indicated that CPB is more seriously damaged under dynamic *** local damage was enhanced,and fine cracks were formed in the interior of the *** is because the CPB cannot dissipate the energy of the high strain rate stress wave in a short loading period.

关键词： high strain rate Compressive strength behavior Cemented paste backfill Split hopkinson pressure bar tailings

Synthesis of porous carbon nanomaterials and their application in tetracycline removal from aqueous solutions

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Chinese Journal of Chemical Engineering 2023年第7期59卷 200-209页

作者： Sufei Wang Mengjie hao Danyang Xiao tianmiao Zhang hua Li Zhongshan chen College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China College of Environmental Science and technology North China Electric Power UniversityBeijing 102206China

the low-cost and efficient elimination of tetracycline from wastewater and to decrease the concentration in soils,sediments,rivers,underground water,or lakes are crucial to human ***,threedimensional porous carbon nanomaterials were synthesized using glucose and Nh_(4)Cl by sugarblowing process at 900℃ and then oxidized under air atmosphere for surface functional group *** prepared 3D porous carbon nanomaterials were applied for the removal of tetracycline from aqueous *** sorption isotherms were well simulated by the Langmuir model,with the calculated sorption capacity of 2378 mg·g^(-1) for C-450 at ph=6.5,which was the highest value of today's reported *** porous carbon nanomaterials showed high stability at acidic conditions and selectivity in high salt *** good recycle ability and high removal efficiency of tetracycline from natural groundwater indicated the potential application of the porous carbon nanomaterials in natural environmental antibiotic pollution *** outstanding sorption properties were attributed to the structures,surface areas and functional groups,strong interactions such as h-bonding,π-π interaction,electrostatic attraction,*** paper highlighted the synthesis of porous carbon nanomaterials with high specific surfaces,high sorption capacities,stability,and reusability in organic chemicals'pollution treatment.

关键词： Porous carbon nanomaterials tetracycline Sorption Pollution management

Effect of ti,Sc and Zr additions on microstructure and mechanical properties of rheo-diecasting Al-6Zn-2Mg-2Cu alloys

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China Foundry 2023年第2期20卷 125-133页

作者： Sai-heng hou Jian Feng Song chen Fan Zhang Da-quan Li State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd.Beijing 100088China GRIMAt Engineering Institute Co. Ltd.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China

the microstructure and mechanical properties of rheo-diecasting Al-6Zn-2Mg-2Cu alloys microalloyed with ti,Sc and Sc+Zr were studied by optical microscopy(OM),scanning electron microscopy(SEM),X-ray diffraction(XRD),hardness testing,and tensile *** swirled equilibrium enthalpy device(SEED)process was introduced to prepare the semisolid *** show that the addition of ti,Sc,and Sc+Zr refines the grain size and improves the uniformity of the semisolid slurry and then suppresses the growth of theα-Al grain during solution heat *** microstructure of the four alloys in as-cast state mainly consists of sphericalα-Al and the Mg(Al,Cu,Zn)_(2)(η)eutectic ***,primary Al_(3)Sc,Al_(3)(Sc,Zr)and Al_(3)Zr are also found in the micro-alloying *** solution and aging heat treatment,most of the Mg(Al,Cu,Zn)_(2) phases dissolve into theα-Al matrix,while part of Mg(Al,Cu,Zn)_(2) phases transform to Al_(2)CuMg(S)***,the coarse primary Al_(3)Sc and Al_(3)(Sc,Zr)still remain in the matrix,and promote crack initiation and *** the tensile strength of 553 MPa,yield strength of 463 MPa and elongation of 13.4%at t6 state,trace ti addition generates more attractive mechanical properties than the other three alloys.

关键词： Al-Zn-Mg-Cu alloys rheo-diecasting microstructure mechanical properties micro-alloying

Pre-sodiation strategy for superior sodium storage batteries

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Chinese Journal of Chemical Engineering 2021年第11期34卷 261-268页

作者： Yongkai Xu haozheng Sun Cunshuang Ma Jingjing Gai Yanhua Wan Weihua chen Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China

the irreversible consumption of sodium in the initial several cycles greatly led to the attenuation of capacity,which caused the low initial coulombic efficiency(ICE)and obvious poor cycle *** can effectively improve the electrochemical performance by compensating the capacity loss in the initial ***,carbon-coated sodium-pretreated iron disulfide(NaFeS_(2)@C)has been synthesized through conventional chemical method and used in sodium metal battery as a cathode *** calculated density of states(DOS)of NaFeS2@C is higher,which implies enhanced electron mobility and improved cycle *** of the highly reversible conversion reaction and the compensation of irreversible capacity loss during the initial cycle,the Na/NaFeS_(2)@C battery achieves ultrahigh initial coulombic efficiency(96.7%)and remarkable capacity(751 mA·h·g^(-1) at 0.1 A·g^(-1)).In addition,highly reversible electrochemical reactions and ultra-thin NaF-rich solid electrolyte interphase(SEI)also benefit for the electrochemical performance,even at high current density of 100 A·g^(-1),it still exhibits a reversible capacity of 136 mA·h·g^(-1),and 343 mA·h·g^(-1) after 2500 cycles at 5.0 A·g^(-1).this work aims to bring up new insights to improve the ICE and stability of sodium metal batteries.

关键词： Pre-sodiation Solid electrolyte interphase Initial coulombic efficiency Sodium metal batteries Interface Electrochemistry