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MOF‐derived 1D/3D N‐doped porous carbon for spatially confined electrochemical CO2 reduction to adjustable syngas

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Carbon Energy 2024年第8期6卷 1-13页

作者： Wei Zhang Hui Li Daming Feng Chenglin Wu Chenghua Sun Baohua Jia xue Liu Tianyi ma Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced materials Institute of Clean Energy ChemistryCollege of ChemistryLiaoning UniversityShenyangLiaoningChina School of Science RMIT UniversityMelbourneVictoriaAustralia School of Pharmaceutical and Chemical Engineering Taizhou UniversityTaizhouZhejiangChina Department of Chemistry and Biotechnology Swinburne University of TechnologyHawthornVictoriaAustralia

Electrochemical reduction of CO_(2)to syngas(CO and H_(2))offers an efficient way to mitigate carbon emissions and store intermittent renewable energy in ***,the hierarchical one‐dimensional/three‐dimensional nitrogen‐doped porous carbon(1D/3D NPC)is prepared by carbonizing the composite of Zn‐MOF‐74 crystals in situ grown on a commercial melamine sponge(MS),for electrochemical CO_(2)reduction reaction(CO_(2)RR).The 1D/3D NPC exhibits a high CO/H_(2)ratio(5.06)and CO yield(31 mmol g^(−1)h^(−1))at−0.55 V,which are 13.7 times and 21.4 times those of 1D porous carbon(derived from Zn‐MOF‐74)and N‐doped carbon(carbonized by MS),*** is attributed to the unique spatial environment of 1D/3D NPC,which increases the adsorption capacity of CO_(2)and promotes electron transfer from the 3D N‐doped carbon framework to 1D carbon,improving the reaction kinetics of CO_(2)*** results and charge density difference plots indicate that the active site of CO_(2)RR is the positively charged carbon atom adjacent to graphitic N on 1D carbon and the active site of HER is the pyridinic N on 1D *** presence of pyridinic N and pyrrolic N reduces the number of electron transfer,decreasing the reaction kinetics and the activity of CO_(2)*** CO/H_(2)ratio is related to the distribution of N species and the specific surface area,which are determined by the degree of spatial confinement *** CO/H_(2)ratios can be regulated by adjusting the carbonization temperature to adjust the degree of spatial confinement *** the low cost of feedstock and easy strategy,1D/3D NPC catalysts have great potential for industrial application.

关键词： electrochemical CO_(2)reduction reaction melamine sponge metal‐organic frameworks porous carbon syngas

A Hybrid Approach for Predicting the Remaining Useful Life of Bearings Based on the RReliefF Algorithm and Extreme Learning machine

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1405-1427页

作者： Sen-Hui Wang Xi Kang Cheng Wang Tian-Bing ma xiang He Ke Yang School of Mechatronics Engineering Anhui University of Science and TechnologyHuainan232001China Institute of Energy Hefei Comprehensive National Science CenterHefei230031China

Accurately predicting the remaining useful life(RUL)of bearings in mining rotating equipment is vital for mining *** research aims to distinguish the features associated with the RUL of bearings and propose a prediction model based on these selected *** study proposes a hybrid predictive model to assess the RUL of rolling element *** proposed model begins with the pre-processing of bearing vibration signals to reconstruct sixty time-domain *** hybrid model selects relevant features from the sixty time-domain features of the vibration signal by adopting the RReliefF feature selection ***,the extreme learning machine(ELM)approach is applied to develop a predictive model of RUL based on the optimal *** model is trained by optimizing its parameters via the grid search *** training datasets are adjusted to make them most suitable for the regression model using the cross-validation *** proposed hybrid model is analyzed and validated using the vibration data taken from the public XJTU-SY rolling element-bearing *** comparison is constructed with other traditional *** experimental test results demonstrated that the proposed approach can predict the RUL of bearings with a reliable degree of accuracy.

关键词： Bearing degradation remaining useful life estimation RReliefF feature selection extreme learning machine

An Experimental Study on the Effect of a Nanofluid on Oil-Water Relative Permeability

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Fluid Dynamics & materials Processing 2024年第6期20卷 1265-1277页

作者： Hui Tian Dandan Zhao Yannan Wu Xingyu Yi Jun ma xiang Zhou Baikouquan Oil Production Plant PetroChina Xinjiang Oilfield CompanyKaramay834000China Research Institute of Petroleum Exploration Development PetroChina Liaohe OilfieldPanjin124010China Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China Oil and Gas Development Haosheng Xincheng Energy TechnologyLtd.of SicuanChengdu610213China

The low porosity and low permeability of tight oil reservoirs call for improvements in the current technologies for oil *** chemical solutions with large molecular size cannot effectively flow through the nanopores of the *** this study,the feasibility of Nanofluids has been investigated using a high pressure high temperature core-holder and nuclear magnetic resonance(NMR).The results of the experiments indicate that the specified Nanofluids can enhance the tight oil recovery *** water and oil relative permeability curve shifts to the high water saturation side after Nanofluid flooding,thereby demonstrating an increase in the water wettability of the *** the Nanofluid flooding process the oil recovery was enhanced by 15.1%,compared to waterflooding *** T2 spectra using the NMR show that after Nanofluid flooding,a 7.18%increment in oil recovery factor was gained in the small pores,a 4.9%increase in the middle pores,and a 0.29%increase in the large *** results confirm that the Nanofluids can improve the flow state in micro-sized pores inside the core and increase the ultimate oil recovery factor.

关键词： Tight oil reservoir nanofluid relative permeability nuclear magnetic resonance T2 spectrum

Silica-modified Pt/TiO_(2) catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

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Chinese Journal of Chemical Engineering 2024年第6期70卷 189-198页

作者： Zhengjian Hou Yuanyuan Zhu Hua Chi Li Zhao Huijie Wei Yanyan Xi Lishuang ma xiang Feng Xufeng Lin College of Chemistry and Chemical Engineering China University of Petroleum(East China)Qingdao 266580China Advanced Chemical Engineering and Energy materials Research Center China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China

Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO_(x) encapsulation of noble metal components to minimize the exposure of noble *** study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles(NPs)with the supported TiO_(2),achieving the moderate suppression of SMSI *** introduction of silica inhibits this encapsulation,as reflected in the characterization results such as XPS and HRTEM,while the Ti^(4+) to Ti^(3+) conversion due to SMSI can still be found on the support ***,the hydrogenation of cinnamaldehyde(CAL)as a probe reaction revealed that once this encapsulation behavior was suppressed,the adsorption capacity of the catalyst for small molecules like H_(2) and CO was enhanced,which thereby improved the catalytic activity and facilitated the hydrogenation of ***,the introduction of SiO_(2) also changed the surface structure of the catalyst,which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C *** manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed.

关键词： Pt catalyst Silica modification Hydrogenation Cinnamaldehyde Strong metal-support interaction

3D Printed Polyimide/Silica Composite Aerogels for Customizable Thermal Insulation from-50℃ to 1300℃

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Chinese Journal of Polymer Science 2024年第7期42卷 936-945,I0007页

作者： Dingyi Yu Tiantian xue Zhuocheng ma Zaiyin Hu Lijuan Long Yue-E Miao Wei Fan Tianxi Liu State Key Laboratory for Modification of Chemical Fibers and Polymer materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi214122China Guizhou Aerospace Wujiang Electro-Mechanical Equipment Co. Ltd.Zunyi563000China School of materials and Architectural Engineering Guizhou Normal UniversityGuiyang550025China

Aerogels are widely used as thermal insulation materials because of their high porosity and low bulk ***,the insulation performance of aerogels is limited to a narrow temperature ***,the preparation of aerogel materials with precisely controlled and complex architectures is still ***,we report 3D printed polyimide/silica aerogel particle(PI/SAP)composite aerogels for thermal insulation in a wide range of temperature with customized *** printability and shape fidelity of 3D printed composite aerogels is improved by adding hydrophilic SAP as a rheology *** resulting PI/SAP composite aerogel exhibits excellent flame-retardant properties and thermal insulation from-50℃ to 1300℃.Moreover,the PI/SAP composite aerogel with customized shape can be applied for battery insulation at subzero temperatures,promising to be used as customizable and stable insulating materials in a variety of complex and extreme applications.

关键词： 3D printing Polyimide Aerogel Silica Thermal insulation

Improvement of impact properties of Al-Si-Mg alloy via solution treatment and joint modification with Sr and La

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Rare Metals 2024年第7期43卷 3301-3313页

作者： Xiong-Ling Zheng Shao-xiang Li Jia-Le ma Qing-Yan Xu Hai-Dong Zhao Zhi-Qiang Han Key Laboratory for Advanced materials Processing Technology Ministry of EducationSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China National Engineering Research Center of Near-Net Shape Forming for Metallic materials South China University of TechnologyGuangzhou 510641China

An effort to obtain superior impact properties for Al-7Si-0.35 Mg alloy is presented,where modification with 0.02 wt% Sr and 0.1 wt% La as well as solution treatment was jointly *** samples were solution treated at 535℃ for 15 min to 12 *** microstructure,fracture mechanism,and their correlation with the impact properties of the alloy were studied in detail mainly through optical microscopy(OM),scanning electron microscopy(SEM) and oscillography impact *** results show that the addition of Sr and La refined the eutectic Si particles significantly from~ 2.05 μm(modified with Sr alone) to~ 0.75 μm in as-cast microstructure,leading to a very homogeneous distribution of spheroidized Si particles in the alloy solution treated at 535℃ for 8 *** alloy exhibits excellent impact toughness up to 75 J·cm^(-2),which is much higher than the maximum impact toughness of the alloys modified by Sr alone(~ 46 J·cm^(-2)).The major reason for this remarkable increase in the impact property is the dramatic increase in crack initiation *** dispersoid-free zones(DFZs)near the eutectic regions mainly consist of the ductile Al-matrix,which exhibits excellent *** ductile Al-matrix of the DFZs hinders the crack propagation,resulting in a significant increase in crack propagation energy.

关键词： Aluminum alloys Modification Solution treatment Microstructure Impact properties Fracture mechanism

A general synthetic strategy for N, P co-doped graphene supported metal-rich noble metal phosphides for hydrogen generation

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Green Energy & Environment 2024年第1期9卷 152-162页

作者： Jingwen ma xiang Li Guangyu Lei Jun Wang Juan Wang Jian Liu Ming Ke Yang Li Chunwen Sun School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing100083China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Lab of Advanced Nano-structures&Transfer Processes Department of Chemical EngineeringTianjin UniversityTianjin300354China PetroChina Planning and Engineering Institute Beijing100083China

The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a *** have attracted increasing attentions,but the preparation process often needs toxic regents or dangerous reaction ***,we develop a general green method to fabricate metal-rich NMPs anchored on NPG through pyrolyzing DNA cross-linked *** obtained Ru_(2) P-NPG exhibits an ultrasmall overpotential of 7 mV at 10 ma cm^(2) and ultralow Tafel slope of 33 mV dec^(-1) in 1.0 mol L?1 KOH,even better than that of commercial Pt/*** addition,Ru 2 P-NPG also shows low overpotentials of 29 and 78 mV in 0.5 mol L^(-1) H_(2)SO_(4) and 1.0 mol L^(-1) PBS,*** superior activity can be attributed to the ultrafine dispersion of Ru 2 P nanoparticles for more accessible sites,more defects formed for abundant active sites,the two-dimensional plane structure for accelerated electron transfer and mass transport,as well as the regulation of electron distribution of the ***,the synthetic method can also be applied to prepare other metal-rich noble metal phosphides(Pd_(3)P-NPG and Rh_(2)P-NPG),which also exhibits high activity for *** work provides an effective strategy for designing NMP-based electrocatalysts.

关键词： Noble metal phosphides Electrocatalyst Deoxyribonucleic acid Hydrogen evolution pH universal

Low friction under ultrahigh contact pressure enabled by self-assembled fluorinated azobenzene layers

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Friction 2024年第7期12卷 1434-1448页

作者： Dandan xue Zhi XU Linyuan GUO Wendi LUO Liran ma Yu TIAN Ming ma Qingdao ZENG Ke DENG Wenjing ZHANG Yichun XIA Shizhu WEN Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China National Center for Nanoscience and Technology Beijing 100190China

Extensive efforts have been made to pursue a low-friction state with promising applications in many fields,such as mechanical and biomedical *** which,the load capacity of the low-friction state has been considered to be crucial for industrial ***,we report a low friction under ultrahigh contact pressure by building a novel self-assembled fluorinated azobenzene layer on an atomically smooth highly-oriented pyrolytic graphite(HOPG)*** friction coefficients could be as low as 0.0005 or even lower under a contact pressure of up to 4 *** demonstrates that the low friction under ultrahigh contact pressure is attributed to molecular *** fluorination leads to effective and robust lubrication between the tip and the self-assembled layer and enhances tighter rigidity which can reduce the stress concentration in the substrate,which was verified by density functional theory(DFT)and molecular dynamics(MD)*** work provides a new approach to avoid the failure of ultralow friction coefficient under relatively high contact pressure,which has promising potential application value in the future.

关键词： ultrahigh contact pressure self-assembled layer fluorination robust lubrication

Cancer stem cell-immune cell crosstalk in the tumor microenvironment for liver cancer progression

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Frontiers of Medicine 2024年第3期18卷 430-445页

作者： Yue ma Hongwei Lv Fuxue Xing Wei xiang Zixin Wu Qiyu Feng Hongyang Wang Wen Yang Cancer Research Center First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei230027China National Center for Liver Cancer Naval Medical University(Second Military Medical University)Shanghai201805China International Co-operation Laboratory on Signal Transduction Eastern Hepatobiliary Surgery HospitalNaval Medical University(Second Military Medical University)Shanghai200438China Shanghai Key Laboratory of Hepato-biliary Tumor Biology Shanghai200438China Key Laboratory of Signaling Regulation and Targeting Therapy of Liver Cancer Ministry of EducationShanghai200438China

Crosstalk between cancer cells and the immune microenvironment is determinant for liver cancer progression.A tumor subpopulation called liver cancer stem cells(CSCs)significantly accounts for the initiation,metastasis,therapeutic resistance,and recurrence of liver *** evidence demonstrates that the interaction between liver CSCs and immune cells plays a crucial role in shaping an immunosuppressive microenvironment and determining immunotherapy *** review sheds light on the bidirectional crosstalk between liver CSCs and immune cells for liver cancer progression,as well as the underlying molecular mechanisms after presenting an overview of liver CSCs characteristic and their ***,we discuss the potential application of liver CSCs-targeted immunotherapy for liver cancer treatment.

关键词： liver cancer cancer stem cell immune cell immunotherapy