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Nano Research 2024年第9期17卷 8112-8118页

作者： Zi-Jun Zou shi-yi yin Yao Tang Sheng-Liang Zhong Lei Wang shi-Long Xu Hai-Wei Liang College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China

Carbon-supported platinum-lanthanum(Pt-Ln)intermetallic compound(IMC)nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel ***,the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering,resulting in significant reduction of the electrochemical surface area and mass-based ***,we prepare small-sized M-doped Pt_(5)Ce(M=Ga,Cd,and Sb)IMCs catalysts via a low-melting-point metal doping *** speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt_(5)Ce *** prepared Ga-doped Pt_(5)Ce catalyst exhibits a higher electrochemical active surface area(81 m^(2)·gPt^(-1))and a larger mass activity(0.45 A·mgPt^(-1)at 0.9 V)over the undoped Pt_(5)Ce and commercial Pt/C *** the membrane electrode assembly test,the Ga-doped Pt_(5)Ce cathode delivers a power density of 0.98 W·cm^(-2)at 0.67 V,along with a voltage loss of only 27 mV at 0.8 A·cm^(-2)at the end of accelerated stability test.

关键词： P5Ce low-melting-point metal small-sized intermetallic compound catalysis fuel cells

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao Sheng Xiao-ying Zhuang xin-yi Li Gen-Sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan Qi xin Zhang Jun Li Dong-liang Zhao shi-hai Guo Yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Recent advances in droplet-based microfluidics in liquid biopsy for cancer diagnosis

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Droplet 2024年第1期3卷 1-27页

作者： Jingyu shi Yu Zhang Yadi Fan yi LiuMo Yang Department of Biomedical Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Mechanical and Automotive Engineering Royal Melbourne Institute of TechnologyMelbourneAustralia

Liquid biopsy,a noninvasive technique to obtain tumor information from body fluids,is an emerging technology for cancer diagnosis,prognosis,and monitoring,providing crucial support for the realization of precision *** main biomarkers of liquid biopsy include circulating tumor cells,circulating tumor DNA,microRNA,and circulating tumor *** liquid biopsy detection methods include flow cytometry,immunoassay,polymerase chain reaction(PCR)-based methods,and next-generation sequencing(NGS)-based methods,which are time-consuming,labor-intensive,and cannot reflect cell ***-based microfluidics with high throughput,low contamination,high sensitivity,and single-cell/single-molecule/single-exosome analysis capabilities have shown great potential in the field of liquid *** review aims to summarize the recent development in droplet-based microfluidics in liquid biopsy for cancer diagnosis.

关键词： diagnosis biopsy fluid

Engineering high-performance dielectric chiral shells with enhanced chiral fields for sensitive chiral biosensor

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Rare Metals 2024年第3期43卷 1197-1206页

作者： yi-Fan Wang Shan-Shan Huang Zhen-Dong Dai shi-Lin Xian Xuan-Nan Wu Fu-Hua Gao yi-Dong Hou College of Physics Sichuan UniversityChengdu610065China Graduate School of Sichuan University Sichuan UniversityChengdu610065China

Chiral metamaterials have been a topic of significant research interest in recent years due to their potential for various applications in nanophotonic devices and chiral ***,the intrinsic Ohmic loss in surface plasmonic resonance has limited their practical use,resulting in large light dissipation and weak chiroptical ***,we report on the development of high-performance dielectric chiral shells(DCS)through a two-step Si deposition process on a self-assembled microsphere *** form DCS sample completely oyercomes the cancelation effect originated from the disorder property of the micro-sphere monolayer in macroscale,and at a wavelength of approximately 710 nm,the measured optimal chiral signal(g-factor)and transmittance can reach up to 0.7 and 0.3,*** strong chiroptical effect comes from the asymmetric circular displacement currents(i.e.,magnetic modes)enabled by the specific shell *** chiral shell geometry,electromagnetic properties,sensor sensitivity of chiral molecules and figure of merit are systematically *** DCSs demonstrate highly sensitive detection of chiral biomolecules owing to their easily accessible geometry and enhanced uniform chiral field.

关键词： Dielectric chiral shells(DCS) Si deposition Magnetic resonance Highly sensitive sensor Chiral field

Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades

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Fluid Dynamics & Materials Processing 2024年第2期20卷 337-348页

作者： Yuanjun Dai xin Wei Baohua Li Cong Wang Kunju shi Mechanical College Shanghai Dian Ji UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of EngineeringUrumqi830091China

To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal *** to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,theﬁfth order increases in the middle,and theﬁrst order increases the *** damping ratio data indi-cate that,in general,theﬁrstﬁve-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and theﬁrstﬁve-order damping ratios of trailing-edge worn blades-3 are slightly *** mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be ***,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades.

关键词： Wind turbine modal test natural frequency damping ratio mode shape

Effect of perioperative chemotherapy on resection of isolated pulmonary metastases from colorectal cancer:A single center experience

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3457-3470页

作者： Zhao Gao Xuan Jin ying-Chao Wu shi-Jie Zhang shi-Kai Wu xin Wang Department of Medical Oncology Peking University First HospitalBeijing 10000China Department of General Surgery Peking University First HospitalBeijing 10000China Department of Thoracic Surgery Peking University First HospitalBeijing 10000China

BACKGROUND Numerous studies have assessed surgical resection as a standard treatment option for patients with colorectal cancer(CRC)and resectable pulmonary metastases(PM).However,the role of perioperative chemotherapy after complete resection of isolated PM from patients with CRC patients remains *** hypothesize that perioperative chemotherapy does not provide significant survival benefits for patients undergoing resection of PM from *** To determine whether perioperative chemotherapy affects survival after radical resection of isolated PM from *** We retrospectively collected demographic,clinical,and pathologic data on patients who underwent radical surgery for isolated PM from *** survival(CSS)and disease-free survival were calculated using Kaplan-Meier ***-group differences were compared using the log-rank *** multivariate analysis,Cox regression was utilized when *** This study included 120 patients with a median age of 61.6 *** 5-year CSS rate was 78.2%,with 36.7% experiencing *** resection for isolated PM resulted in a 5-year CSS rate of 50.0% for second *** chemotherapy(P=0.079)did not enhance survival *** associated with improved survival included fewer metastatic lesions[hazard ratio(HR):2.51,P=0.045],longer disease-free intervals(HR:0.35,P=0.016),and wedge lung resections(HR:0.42,P=0.035).Multiple PM predicted higher recurrence risk(HR:2.22,P=0.022).The log-rank test showed no significant difference in CSS between single and repeated metastasectomy(P=0.92).CONCLUSION Perioperative chemotherapy shows no survival benefit post-PM resection in ***-free intervals and fewer metastatic lesions predict better *** metastasectomy is warranted for eligible patients.

关键词： Pulmonary metastasis Colorectal cancer Perioperative chemotherapy Survival Repeated pulmonary metastasectomy

Intra-Oceanic Subduction Termination and Reinitiation of the Eastern Neo-Tethys in Myanmar

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Journal of Earth Science 2024年第3期35卷 1053-1058页

作者： yi Chen Qinghua Zhang Lin Chen Kaihui shi Kyaing Sein State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Myanmar Geosciences Society Hlaing University CampusYangon 11062Myanmar

Subduction initiation and termination represent the birth and death of a subduction zone and are inevitable elements of terrestrial plate *** evidence demonstrates that subduction zone processes did not operate continuously and might involve multiple initiation and termination stages(Stern,2004),characterized by sustained subduction-zone death and *** geological and numerical studies focus on subduction initiation processes/mechanisms(see reviews in Yang,2022);however,subduction termination is often studied numerically at continental margins(Gerya,2022).How subduction termination proceeds in intra-oceanic settings remains enigmatic due to lacking geological records.

关键词： Eastern terrestrial continental

Advances of high-performance LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode materials and their precursor particles via co-precipitation process

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Particuology 2024年第3期86卷 67-85页

作者： Wenbiao Liang yin Zhao Liyi shi Zhuyi Wang yi Wang Meihong Zhang Shuai Yuan School of Materials Science and Engineering Shanghai UniversityShanghai200444China Research Center of Nanoscience and Nanotechnology Shanghai UniversityShanghai200444China Emerging Industries Institute Shanghai UniversityJiaxingZhejiang314006China

Layered LiNi_(1-x-y)Co_(x)M_(y)O_(2)(M=Mn or Al)is a promising cathode material for lithium-ion batteries due to its high specific capacity and acceptable manufacturing ***,the polycrystalline LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode material suffers from disordered orientation of primary particles and poor geometric symmetry of secondary particles,which severely hampers the migration of Lit ***,the resulting anisotropy accelerates the disintegration of the secondary particle structure,significantly affecting the electrochemical performance of the polycrystalline *** spite of less grain boundary,the single-crystal LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathodes still suffer from severe microcracks generated by repeated planar gliding during cycling,which poses a great challenge to the cycling stability of single-crystal ***'s worth noting that the microstructure of the cathode material is mainly inherited from its ***,it is necessary to deeply understand the influence of the microstructure of Ni_(1-x-y)Co_(x)M_(y)(OH)2 on the electrochemical properties of LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode materials,so as to optimize the production process of preparing high-performance cathode *** this review,we summarize recent advances in the research and development of Ni-rich cathode precursor ***,the challenges faced by the Ni-rich hydroxide precursor materials are presented,including the effect of primary particle morphology and arrangement on the electrochemical performance of cathode materials,the influence of secondary particle morphology on lithium insertion reactions in cathode,and the effect of particle size on the microcracking of single-crystal ***,the presentation of the conventional co-precipitation reactor,the mechanism of precursor particle growth,and the influence of coprecipitation parameters are described in ***,the strategies are systematically discussed to solve the cha

关键词： Lithium-ion batteries Cathode materials Co-precipitation Ni-rich layered oxides Single crystal Precursor particles

High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin xin-Yu Wang Qaiser Mahmood Zhi-xin Yu yi-Zhou Wang Song Zou Tong-Ling Liang Wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene