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Integrated interconnected porous and lamellar structures realized fast ion/electron conductivity in high-performance lithium-sulfur batteries

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Chinese Chemical Letters 2024年第6期35卷 161-167页

作者： ya Song Mingxia Zhou Zhu chen Huali Nie Jiao-Jing Shao guangmin Zhou School of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Medical College of Guizhou University Guiyang 550025China College of Biological Science and Medical Engineering Donghua UniversityShanghai 201620China Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

The practical application of high-energy-density lithium-sulfur(Li-S)batteries have been highly praised for energy storage devices,while are largely hindered by the“shuttling effect”.Herein,core-shell carbon spheres composed of interlinked porous core and lamellar shell were designed to restrain the polysulfide *** microporous structure with pore size of around 1 nm effectively trap lithium ***,the interconnected porous core shortens the ion transfer distance and the lamellar carbon shell endows the carbon spheres with fast electron conduction,finally facilitating polysulfide conversion ***,the Li-S batteries with the carbon spheres as the interlayer show high discharge specific capacity of 1002 m Ah/g at 2 C with 574 m Ah/g remaining after 600 cycles,and high areal capacity of 5.48 m Ah/cm^(2) with sulfur loading of 4.67 mg/cm^(2) at 0.1 *** corresponding pouch cells also exhibit stable cycling stability with an initial discharge specific capacity of 1082 m Ah/g at 0.1 C.

关键词： Interlayer Shuttle effect Strong adsorption Porous carbon spheres Lithium-sulfur batteries

Effects of different orthokeratology lens designs on slowing axial length elongation in children with myopia

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1843-1849页

作者： Hai-Long Ni Xiang chen Du-ya chen Pei-Ke Hu Zhi-Yi Wu Eye Center the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To elucidate whether differences exist in the impact on retarding the elongation of axial length(AL)among children with myopia when utilizing orthokeratology(ortho-k)lenses employing the corneal refractive therapy(CRT)design versus those employing the vision shaping treatment(VST)***:This retrospective clinical trial aimed to collect and analyze AL data from individuals who wore ortho-k lenses for three years.A total of 654 subjects were enrolled and prescribed one of the three specific brands of ortho-k lenses:CRT,Euclid,and *** study’s primary focus was to compare the rates of AL elongation and myopic progression across these three brands of ortho-k ***:In the 3-year follow-up,the AL elongation exhibited variations of 0.73±0.36 mm in the CRT lens group,0.59±0.37 mm in the Euclid lens group,and 0.63±0.38 mm in the Mouldway lens group.A noteworthy disparity emerged between the CRT and Mouldway groups(P<0.01),as well as between the CRT and Euclid groups(P<0.001).Additionally,it was observed that 32.1%of participants who wore CRT lenses experienced a decelerated progression of myopia,in contrast to 47.2%in the Euclid group and 44.4%in the Mouldway *** analyses revealed a statistically significant distinction between the CRT and Euclid groups(P<0.01),and similarly,the CRT group demonstrated a statistically significant difference when compared to the Mouldway group(P<0.05).CONCLUSION:Ortho-k lenses represent a pragmatic strategy for mitigating the advancement of *** contradistinction to ortho-k lenses utilizing the CRT design,those employing the VST design exhibited a more favorable impact regarding retarding AL elongation.

关键词： myopia orthokeratology design axial length

Regulating metal-acid double site balance on mesoporous SiO2-Al2O3 composite oxide for supercritical n-decane cracking

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Petroleum Science 2024年第4期21卷 2881-2891页

作者： Liu-Ling chen Jun Zhang Chun-guang Li Li-Qun Fei Bo Wang chen-Qi Zhang Yi Jiao Jian-Li Wang Institute of New Energy and Low-Carbon Technology Sichuan University Engineering Research Center of Combustion and Cooling for Aerospace Power Ministry of Education School of Chemical Engineering Sichuan University State Key Laboratory of Industrial Vent Gas Reuse Southwest Institute of Chemical Co. Ltd Science and Technology on Scramjet Laboratory Beijing Power Machinery Research Institute

The balance between metal and acid sites directly affects the preparation of high-performance cracking catalysts with high heat sink and low ***,how to control acid-metal sites balance and its relationship with cracking performance are reported *** this work,a series of Pt/Al2O3-SiO2dual sites catalysts with different metal to acid active sites ratio(CM/CSA) were constructed by ethanolassisted impregnation method and the impact on n-decane cracking under supercritical conditions was systematically and deeply *** results showed that the conversion and carbon deposition increased gradually with varied CM/CSAand reached the balance at CM/CSAof *** proper ratio CM/CSA（0.13） can balance the deep dehydrogenation coking over metal active sites and high heat sink of cracking over acid active sites,the chemical heat sink reaches amazing 1.75 MJ/kg and carbon deposition is only22.03 mg/cm2at 750℃.Meanwhile,the few metal sites at low CM/CSAand the few strong acid sites at high CM/CSAare the main factors limiting the cracking *** CM/CSAlimit the activation of C-H bond and deep dehydrogenation of coking precursor,resulting in relative low cracking activity and carbon deposition,while high CM/CSAlimit the activation of C-C bond and increase the deep *** this contribution,design and construction of metal-acid dual sites can not only provide the technical solution for the preparation of high heat sink and low coking cracking catalyst,but also deepen the understanding of the cracking path of hydrocarbon fuel.

关键词： Metal-acid dual sites balance Catalytic cracking Hydrocarbon fuels Chemical heat sink Carbon deposition

基于JPEG2000的医学图像感兴趣区编码与渐进传输

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计算机工程与应用 2007年第14期43卷 204-206页

作者：陈军波陈亚光中南民族大学生物医学工程研究所武汉430074

针对JPEG2000标准使用的两种感兴趣编码方法,最大位移法和一般位移法对医学图像处理的不足,采用了一种分步提升方法,以完成医学图像感兴趣区域编码,以及图像中病灶区域和非病灶区域图像质量的自由调整。并根据率失真优化策略组织压缩码... 详细信息

针对JPEG2000标准使用的两种感兴趣编码方法,最大位移法和一般位移法对医学图像处理的不足,采用了一种分步提升方法,以完成医学图像感兴趣区域编码,以及图像中病灶区域和非病灶区域图像质量的自由调整。并根据率失真优化策略组织压缩码流,实现医学图像的感兴趣区域编码与渐进传输。实验结果表明,该方法可在低码率下实现感兴趣区域的高保真度压缩,有效提高图像压缩和传输的效率。

关键词：医学图像感兴趣区域编码渐进式传输

Robust textile-based spoof plasmonic frequency scanning antenna for on-body IoT applications

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Science China(Information Sciences) 2024年第8期67卷 269-284页

作者： Zhao-Min chen Jun-Lin ZHAN Hao chen ya LI Hongjun HE Wu yaNG Zhen-Guo LIU Wei-Bing LU State Key Lab of Millimeter Waves School of Information Science and EngineeringSoutheast University Center for Flexible RF Technology Frontiers Science Center for Mobile Information Communication and SecuritySoutheast University Future Research Laboratory China Mobile Research Institute Purple Mountain Laboratories

Securing a comfortable, wearable compact frequency beam scanning antenna(FBSA) with robustness to deformation, low specific absorption rate(SAR), and good coverage of the surrounding environment for Internet of Things(IoT) applications, such as on-body navigation and wireless communication is an emerging challenge. In this work, a robust textile-based spoof plasmonic frequency scanning antenna utilizing higher-order modes is presented, which is also robust to deformation caused by the activities of the human body. The innovative design of the element ensures the high-efficiency transmission of the fundamental mode of spoof surface plasmon polaritons(SSPP) structure, providing the potential of being a multifunctional composite device in the compact on-body network. Besides, an artificial magnetic conductor(AMC) is designed underneath the SSPP structure, obtaining a low SAR value(0.113 W/kg), which ensures the safety of users. As a practical realization of this concept, a textile-based spoof plasmonic antenna was fabricated in the microwave regime and the performed experimental results show the proposed antenna has a single-beam radiation characteristic with a 70° beam scanning angle range when the frequency is 4.7–6.0 GHz with a high average realized gain of 13.15 dBi. And it still maintains a steady performance when faced with structure deformation, which proves its robustness. Wireless communication quality experiments are performed to demonstrate the proposed antenna can measure the angles of targets and realize wireless signal transmission to specific targets as the frequency varies, it may find great potential in the field of on-body IoT applications.

关键词： frequency beam scanning antenna (FBSA) Internet of Things (IoT) on-body communication spoof surface plasmon polaritons (SSPP) textile-based antenna

Structure of Potassium of Undecatungstomononickelosilicate

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Chinese Journal of Structural Chemistry 1995年第6期 51-54页

作者： Qu Lun-Yu Ma Rong-Hua chen ya-guang(Department of Chemistry, Northeast Normal University,Changchun 130024) Xing yan Lin Yong-Hua(Changchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022)

The compound K4[α-SiNiW11O38]·10H2O,Mr=3053.86,crystallizes in the orthorhombic, space group Pnn2 with cell dimensions a=14.203（8）,b=14.214（6）,c=12.460（3）,V=2515（2）,Z=2,Dc=4.03 g/cm￣3,λ（MoKα）=0.71069,μ=273.1 cm（-1）,F（000）=*** structure was solved by direct *** least-square refinement based on 1190 observed reflections[I> 6σ（I）] converged to a final R=*** anion in the title compound is of α type Keggin structure,although the octahedron MO6 is greatly distorted. Atoms Ni and W are statistically distributed in the crystal.

关键词： crystal structure α-isomer nickel-monosubstituted heteropoly compound

Acetylene/argon mixture plasma to build ultrathin carbon bridge of CF_(x)/C/MnO_(2) for high-rate lithium primary battery

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Rare Metals 2024年第6期43卷 2574-2584页

作者： Da-Wei Zou Xing-guang Fu Gao-Bang chen Yi-Fan Liu Bao-Shan Wu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 31300lChina

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate ***,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)*** CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)*** with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

关键词： C_(2)H_(2)/Ar plasma Fluorinated carbon Lithium primary battery MnO_(2)

Covalently Bonded Ni Sites in Black Phosphorene with Electron Redistribution for Efficient Metal‑Lightweighted Water Electrolysis

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Nano-Micro Letters 2024年第6期16卷 233-245页

作者： Wenfang Zhai ya chen yaoda Liu Yuanyuan Ma Paranthaman Vijayakumar Yuanbin Qin Yongquan Qu Zhengfei Dai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China SSN Research Centre SSN College of EngineeringChennaiTamil Nadu 603110India

The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but *** this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)*** a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal *** is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER *** 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity *** work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts.

关键词： Black phosphorus Water electrolysis Electrocatalyst Electron redistribution Covalent functionalization

Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019

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Zoological Research 2024年第2期45卷 439-450页

作者： Yi Lu Xin-Rong Xu Bing-yao chen Thomas A Jefferson Holly Fearnbach guang yang Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingJiangsu 210023China Clymene Enterprises LakesideCalifornia 92040USA Marine Mammal Research SR3SeaLife ResponseRehabilitation and ResearchWA 98275USA Southern Marine Science and Engineering guangdong Laboratory(guangzhou) No.1119Haibin RoadNansha DistrictGuangzhouGuangdong 511458China

As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community ***,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still *** the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the *** both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small ***,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two *** this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 *** observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external ***,the study proposes distinct conservation measures tailored to each of the two main clusters.

关键词： Social differentiation Social structure Sousa chinensis Dynamics Conservation