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Science China(Technological Sciences) 2024年第3期67卷 696-708页

作者： GUO MingHui RONG YouMin HUANG Yu FENG xiaolin HU HaiDong WU CongYi ZHANG GuoJun State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Faculty of Engineering and Life Sciences Universiti Selangor Bestari JayaSelangor 45600Malaysia

Oil film vortex severely reduces the stability of hydrostatic bearings. A solid-liquid interface with drag and slip properties can weaken the oil film vortex of the bearing. Here, a combined picosecond laser ablation and chemical modification method is proposed to prepare surfaces with microbulge array structure on 6061 aluminum alloy substrates. Because of the low surface energy of the perfluorododecyltriethoxysilane modification and the bulge geometry of the microbulge array structure, the surface shows excellent superhydrophobicity. The optimum contact angle in air for water is 164°, and that for oil is 139°. Two surfaces with “lotus-leaf effect” and “rose-petal effect” were obtained by controlling the processing parameters. The drag reduction properties of superhydrophobic surfaces were systematically investigated with slip lengths of 22.26 and 36.25 μm for deionized water and VG5 lubricant, respectively. In addition, the superhydrophobic surface exhibits excellent mechanical durability and thermal stability. The proposed method provides a new idea for vortex suppression in hydrostatic bearings and improves the stability of bearings in high-speed operation.

关键词： superhydrophobicity surface ultrafast laser drag reduction solid-liquid interface microbulge array structure

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Solid Bronsted acidity boosts adsorption reactivity of nano-adsorbent for water decontamination

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 23-34页

作者： Sikai Cheng Zhixian Li Kaisheng Zhang Qingrui Zhang xiaolin Zhang Bingcai Pan State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Environmental Materials and Pollution Control Laboratory Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Heavy Metal Deep-remediation in Water and Resource Reused Qinhuangdao 066004China Research Center for Environmental Nanotechnology(ReCENT) Nanjing UniversityNanjing 210023China

Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water *** addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be *** tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is *** feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward *** enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR ***,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic *** tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum *** study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.

关键词： Nanocomposite Selective adsorption Fluoride removal dual Lewis and Bronsted acidity Regeneration

Demand and key technology for a LEO constellation as augmentation of satellite navigation systems

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Satellite Navigation 2024年第1期5卷 1-9页

作者： Yuanxi Yang Yue Mao Xia Ren xiaolin Jia Bjiao Sun Xi’an Research Institute of Surveying and Mapping Xi’an710054ShaanxiChina State National Key Laboratory of Geo-Information Engineering Xi’an710054ShaanxiChina

A Low Earth Orbit(LEO)constellation augmenting satellite navigation is important in the future development of Global Navigation Satellite System(GNSS).GNSS augmented by LEO constellations can improve not only the accuracy of Positioning,Navigation,and Timing(PNT),but also the consistency and reliability of secure PNT *** paper mainly analyzes the diverse demands of different PNT users for LEO augmented GNSS,including the precision demand in real-time,the availability demand in special areas,the navigation signal enhancement demand in complex electromagnetic environments,and the integrity demand with high ***,the possible contributions of LEO constellations to PNT performance are analyzed from multiple aspects.A particular attention is paid to the special PNT user requirements that cannot be fulfilled with existing GNSS,such as the PNT service demand in the polar regions and the onboard GNSS orbit determination demand of some LEO *** key technologies to be considered in the constellation design,function realization,and payload development of the LEO-augmented navigation system are summarized.

关键词： Low earth orbit navigation constellation Accuracy augmentation Orbit determination Integrity

智能反射面辅助雷达通信双功能系统的多载波波形优化方法

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雷达学报（中英文） 2022年第2期11卷 240-254页

作者：田团伟邓浩鲁建华杜晓林河南大学物理与电子学院开封475001 空军航空大学航空作战勤务学院长春130022 烟台大学计算机与控制工程学院烟台264005

雷达通信一体化是解决频谱资源拥挤问题的有效途径之一,而共享波形设计是同时实现雷达与通信功能的关键技术,该文旨在解决智能反射面(IRS)辅助雷达通信双功能(DRC)系统的多载波波形优化问题。首先,通过最大化传输功率、通信码字错误率(W... 详细信息

雷达通信一体化是解决频谱资源拥挤问题的有效途径之一,而共享波形设计是同时实现雷达与通信功能的关键技术,该文旨在解决智能反射面(IRS)辅助雷达通信双功能(DRC)系统的多载波波形优化问题。首先,通过最大化传输功率、通信码字错误率(WEP)、旁瓣幅度与IRS反射系数约束下的雷达互信息(RMI),构建了双功能发射波形、IRS反射单元、雷达与通信接收波束联合优化模型。其次,提出了基于交替方向最大化(ADM)的多载波波形优化算法,通过将原非凸优化问题分解为若干低复杂度子问题并迭代优化,获得了多载波波形功率分配策略的局部最优解。最后,仿真结果表明,ADM算法能同时实现雷达与通信功能;相较于现有方法有效提升了IRS辅助DRC系统的雷达与通信性能。

关键词：雷达通信双功能智能反射面多载波波形互信息码字错误率

Dissolvable temporary barrier:a novel paradigm for flexible hydrogel patterning in organ-on-a-chip models

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Bio-Design and Manufacturing 2024年第2期7卷 153-166页

作者： Ding Wang Qinyu Li Chenyang Zhou Zhangjie Li Kangyi Lu Yijun Liu Lian Xuan xiaolin Wang Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Ophthalmology LKS Faculty of MedicineThe University of Hong KongHong Kong 999077China Institute of Medical Robotics Shanghai Jiao Tong UniversityShanghai 200240China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240China National Center for Translational Medicine(Shanghai)SHU Branch Shanghai UniversityShanghai 200444China

A combination of hydrogels and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as *** hydrogel patterningwith awell-controlled spatial distribution is typically achieved by embedding sophisticated microstructures to act as a ***,these physical barriers inevitably expose cells/tissues to a less physiologically relevant microenvironment than in vivo ***,we present a novel dissolvable temporary barrier(DTB)strategy that allows robust and flexible hydrogel patterning with great freedom of design and desirable flow stimuli for cellular *** key aspect of this approach is the patterning of a water-soluble rigid barrier as a guiding path for the hydrogel using stencil printing technology,followed by a barrier-free medium perfusion after the dissolution of the *** and multiple tissue compartments with different geometries can be established using either straight or curved DTB *** effectiveness of this strategy is further validated by generating a 3D vascular network through vasculogenesis and angiogenesis using a vascularized microtumor *** a new proof-of-concept in vasculature-on-a-chip,DTB enables seamless contact between the hydrogel and the culture medium in closed microdevices,which is an improved protocol for the fabrication ofmultiorgan ***,we expect it to serve as a promising paradigm for organ-on-a-chip devices for the development of tumor vascularization and drug evaluation in the future preclinical studies.

关键词： Dissolvable temporary barrier Hydrogel patterning Microfluidics Organ-on-a-chip Vascularization

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基于加权准则的雷达博弈波形设计

电子科技大学学报 2022年第6期51卷 866-874页

作者：董军杜晓林崔国龙余显祥田团伟烟台大学计算机与控制工程学院山东烟台264005 电子科技大学信息与通信工程学院成都611731 河南大学物理与电子学院河南开封475001

在复杂的实战环境中,雷达的先验信息具有很大的不确定性,且由于干扰更加智能化,导致实战中雷达的探测性能再度降低。为提高电子战雷达的探测性能,提出了一种基于互信息与信干噪比加权准则的雷达博弈波形设计方法。首先建立了互信息和信... 详细信息

在复杂的实战环境中,雷达的先验信息具有很大的不确定性,且由于干扰更加智能化,导致实战中雷达的探测性能再度降低。为提高电子战雷达的探测性能,提出了一种基于互信息与信干噪比加权准则的雷达博弈波形设计方法。首先建立了互信息和信干噪比的加权准则,然后设计相应的雷达与干扰博弈模型,最后提出最大边缘重分配算法以解决重复博弈困境,精炼纳什均衡。仿真实验验证了该方法的有效性。

关键词：认知雷达纳什均衡 Stackelberg博弈波形优化设计加权准则

三级职业技能竞赛体系下专业赛学结合机制的研究

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天津职业院校联合学报 2023年第4期25卷 75-80页

作者：杜小林天津市东丽区职业教育中心学校天津300304

结合多年参与市赛、国赛的各类活动以及主持专业建设的经验,从职业教育改革发展、学校专业建设、师资队伍建设、学生成才等方面论述赛学结合机制建设的必要性,剖析赛学结合机制建设中存在的问题,并从完善赛学保障体系、完善赛学融合和... 详细信息

结合多年参与市赛、国赛的各类活动以及主持专业建设的经验,从职业教育改革发展、学校专业建设、师资队伍建设、学生成才等方面论述赛学结合机制建设的必要性,剖析赛学结合机制建设中存在的问题,并从完善赛学保障体系、完善赛学融合和转化机制等方面给出了完善赛学结合机制的建议。完善专业赛学结合机制,保障是根本,融合是关键,转化是核心。

关键词：完善赛学结合融合机制

Factors affecting land dissection density in geomorphological regions of China

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Journal of Mountain Science 2024年第4期21卷 1372-1387页

作者： SUN xiaolin ZHAO Yinjun PENG Peihao CHENG Weiming WEI Yongping YANG Ronghao LI Jiaxu College of Earth Sciences Chengdu University of TechnologyChengdu 610059China School of Civil Engineering Guangxi Polytechnic of ConstructionNanning 530001China Key Laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning 530001China Key Laboratory of Earth Surface Process and Intelligent Simulation(Guangxi) Nanning Normal UniversityNanning 530001China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China School of Earth and Environmental Sciences The University of QueenslandBrisbane 4702Australia School of Geography and Planning Nanning Normal UniversityNanning 530001China

Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters,soil erosion,and other related *** dissection phenomena in China affects large areas with different morphological,pedological,and climatic *** studies have focused on the potential factors influencing the LDD at a watershed ***,these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national ***’s spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be *** study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China’s six first-order geomorphological regions(GR1~GR6).The results yield the following findings:(1)LDD in China ranges from 0~4.55 km/km^(2),which is larger in central and eastern regions than in other regions of China;(2)dominant factors and their dominant risk subcategories vary with each geomorphological region’s primary internal and external forces;(3)the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors;relief degree of land surface(RDLS)is dominant in GR1,GR2,and GR5;the slope is dominant in GR6,soil type is dominant in GR3 and GR4,and lithology plays a critical role in the dominant interactions of GR3,GR4,and GR6;(4)the interactions between factors on LDD’s spatial pattern have a more significant effect than individual factors.

关键词： Land dissection density Influencing factors Regional scale Spatial pattern Geographical detector model Geomorphon-based method China

Mapping upland crop–rice cropping systems for targeted sustainable intensification in South China

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The Crop Journal 2024年第2期12卷 614-629页

作者： Bingwen Qiu Linhai Yu Peng Yang Wenbin Wu Jianfeng Chen xiaolin Zhu Mingjie duan Key Laboratory of Spatial Data Mining&Information Sharing of Ministry of Education Academy of Digital China(Fujian)Fuzhou UniversityFuzhou 350116FujianChina Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural AffairsBeijing 100081China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural *** UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural ***,datasets describing cropping systems are limited in spatial coverage and crop *** UCR is more challenging than crop identification and most existing approaches rely heavily on accurate phenology calendars and representative training samples,which limits its applications over large *** describe a novel algorithm(RRSS)for automatic mapping of upland crop-rice cropping systems using Sentinel-1 Synthetic Aperture Radar(SAR)and Sentinel-2 Multispectral Instrument(MSI)*** indicator,the VV backscatter range,was proposed to discriminate UCR and another two indicators were designed by coupling greenness and pigment indices to further discriminate tobacco or oilseed *** RRSS algorithm was applied to South China characterized by complex smallholder rice cropping systems and diverse topographic *** study developed 10-m UCR maps of a major rice bowl in South China,the Xiang-Gan-Min(XGM)*** performance of the RRSS algorithm was validated based on 5197 ground-truth reference sites,with an overall accuracy of 91.92%.There were7348 km^(2) areas of UCR,roughly one-half of them located in *** UCR was represented mainly by oilseed-UCR and tobacco-UCR,which contributed respectively 69%and 15%of UCR *** patterns accounted for only one-tenth of rice production,which can be tripled by intensification from single rice *** to complex and fragmented subtropical regions suggested the spatiotemporal robustness of the RRSS algorithm,which could be further applied to generate 10-m UCR datasets for application at national or global scales.

关键词： Cropping-pattern mapping Paddy rice Sentinel-1/2 China Sustainable intensification

Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 207-219页

作者： CHEN Biying FANG Lujia LANG Yunchao XU Sheng LIU Congqiang ZHANG Luyuan HOU xiaolin Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Institute of Earth Environments Chinese Academy of SciencesXi’an 710061China

The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological *** better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I *** calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal *** model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in *** spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin *** study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.

关键词： CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin