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Friction 2024年第7期12卷 1564-1579页

作者： Linlin DUAN Dan JIA jian LI jianfang liu Haitao DUAN State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials ProtectionWuhan 430030China Hubei Longzhong Laboratory Xiangyang 441000China College of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430030China

In this work,the advantage of Coulomb repulsion in the intermolecular forces experienced by molecules on the solid–liquid nanosized contact interface is taken,and the superior friction-reducing property of Cu_(3)(PO_(4))2·3H_(2)O(CuP)oil-based additives has been confirmed for titanium ***-dimensional(3D)CuP nanoflowers(CuP-Fs)with a strong capillary absorption effect are prepared to achieve the homogeneous mixing of solid CuP and lubricating *** by CuP-Fs additives for titanium alloy,friction coefficient(COF)can be reduced by 73.68%,and wear rate(WR)reduced by 99.69%.It is demonstrated that the extraordinary friction-reducing property is due to the repulsive solid–liquid interface with low viscous shear force originating from Coulomb repulsion between polar water molecules in CuP and non-polar oil ***,any steric hindrance or connection between this repulsive solid–liquid interface will trigger the adhesion and increase the viscous shear force,for example,dispersant,hydrogen bondings,and shaky adsorbed water ***,the lamellar thickness of CuP and the molecular size of lubricant both have a great influence on tribological *** the lubrication mechanism based on interface Coulomb repulsion is proposed that may help broaden the scope of the exploration in low-friction nanomaterial design and new lubricant systems.

关键词： lubrication nanomaterial additive solid-liquid interface wear

A highly sensitive LITES sensor based on a multi-pass cell with dense spot pattern and a novel quartz tuning fork with low frequency

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Opto-Electronic Advances 2024年第3期7卷 26-34页

作者： Yahui liu Shunda Qiao Chao Fang Ying He Haiyue Sun jian liu Yufei Ma National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150000China Zhengzhou Research Institute Harbin Institute of TechnologyZhengzhou 450000China Advanced Microscopy and Instrumentation Research Center School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China.

A highly sensitive light-induced thermoelectric spectroscopy(LITES)sensor based on a multi-pass cell(MPC)with dense spot pattern and a novel quartz tuning fork(QTF)with low resonance frequency is reported in this *** erbi-um-doped fiber amplifier(EDFA)was employed to amplify the output optical power so that the signal level was further *** optical path length(OPL)and the ratio of optical path length to volume(RLV)of the MPC is 37.7 m and 13.8 cm^(-2),respectively.A commercial QTF and a self-designed trapezoidal-tip QTF with low frequency of 9461.83 Hz were used as the detectors of the sensor,*** target gas selected to test the performance of the system was acetylene(C2H2).When the optical power was constant at 1000 mW,the minimum detection limit(MDL)of the C2H2-LITES sensor can be achieved 48.3 ppb when using the commercial QTF and 24.6 ppb when using the trapezoid-al-tip *** improvement of the detection performance by a factor of 1.96 was achieved after replacing the commer-cial QTF with the trapezoidal-tip QTF.

关键词： light-induced thermoelectric spectroscopy quartz tuning fork multi-pass cell gas sensing

Status of Equities in Prenatal Care Utilization and Changing Patterns among Women in China

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Journal of Reproduction and Contraception 2006年第3期17卷 164-169页

作者： Ying-hui liu Rong-wei YE jian-meng liu Ai-guo REN Song LI Zhu LI Institute of Reproductive and Child Health PekiHg University Beijing 100083 China

Objective To assess the extent and relative changes of the equities in prenatal care utilization among women with different educational attainment in some areas of China. Methods Data were collected in 13 counties/cities covered by Perinatal Health Care Surveillance System established by Institute of Reproductive and Child Health, Peking University. The study population consisted of 103 704 women who delivered single live births in 1994 and 2000. Chi-square and multiple Logistic regression were employed to compare the administrative rates and relative risks. Concentration index was used to assess the relative changes of equities in prenatal care utilization. SPSS 11.5 and Microsoft Excel 2003 were used for analysis. Results The total systematic management rate was 22.1% in 1994 and 57.4% in 2000. The concentration index was -0.046 in 1994 and 0.066 in 2000. In northern areas, the concentration index increased from 0.015 in 1994 to 0.295 in 2000, while it increased from -0.015 in 1994 to 0.062 in 2000 in southern areas. In rural areas, the concentration index increased from O. 002 in 1994 to 0.026 in 2000, while it decreased from 0.042 in 1994 to 0.019 in 2000 in urban areas. Conclusion Inequities in prenatal care utilization in 2000 become more obvious than in 1994, especially in northern areas. More attention should be paid to solve the inequities.

关键词： prenatal care delivery of health care women

Measurement of atmospheric non-reciprocity effects for satellite-based two-way time-frequency transfer

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Photonics Research 2024年第6期12卷 1274-1282页

作者： TING ZENG QI SHEN YUAN CAO jian-YU GUAN meng-ZHE LIAN JIN-jian HAN LEI HOU jian LU XIN-XIN PENG MIN LI WEI-YUE liu JIN-CAI WU YONG WANG JUAN YIN JI-GANG REN HAI-FENG jianG QIANG ZHANG CHENG-ZHI PENG jian-WEI PAN Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Shanghai Research Center for Quantum Science and CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaShanghai 201315China Hefei National Laboratory University of Science and Technology of ChinaHefei 230094China Faculty of Information Science and Engineering Ningbo UniversityNingbo 315211China Key Laboratory of Space Active Opto-Electronic Technology Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

Future optical clock networks will require high-precision optical time-frequency transfer between satellites and ground ***,due to atmospheric turbulence,satellite motion and time delay between the satellite–ground transmission links will cause spatial and temporal variations,respectively,resulting in the breakdown of the time-of-flight reciprocity on which optical two-way time-frequency transfer is ***,we experimentally simulate the atmospheric effects by two-way spatio-temporally separated links between two stationary terminals located 113 km apart and measure the effects for optical two-way time-frequency *** experiment shows that the effect on the link instability is less than 2.3×10^(−19) at 10,000 *** indicates that when the link instability of satellite-ground optical time-frequency transfer is on the order of 10^(−19),it is not necessary to consider the atmospheric non-reciprocity effects.

关键词： breakdown transfer satellite

Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

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Pedosphere 2024年第1期34卷 159-169页

作者： Shufang GUO Yitao ZHANG Limei ZHAI jian liu Hongyuan WANG Hongbin liu State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National Observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(Zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow *** incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) *** incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing *** N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

What benefit can be obtained from magnetic resonance imaging diagnosis with artificial intelligence in prostate cancer compared with clinical assessments?

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Military Medical Research 2024年第2期11卷 268-286页

作者： Li-Tao Zhao Zhen-Yu liu Wan-Fang Xie Li-Zhi Shao jian Lu Jie Tian jian-Gang liu School of Engineering Medicine Beihang UniversityBeijing 100191China School of Biological Science and Medical Engineering Beihang UniversityBeijing 100191China CAS Key Laboratory of Molecular Imaging Institute of AutomationBeijing 100190China University of Chinese Academy of Sciences Beijing 100080China Department of Urology Peking University Third HospitalPeking UniversityBeijing 100191China Key Laboratory of Big Data‑Based Precision Medicine(Beihang University) Ministry of Industry and Information Technology of the People's Republic of ChinaBeijing 100191China Beijing Engineering Research Center of Cardiovascular Wisdom Diagnosis and Treatment Beijing 100029China

The present study aimed to explore the potential of artificial intelligence(AI)methodology based on magnetic resonance(MR)images to aid in the management of prostate cancer(PCa).To this end,we reviewed and summarized the studies comparing the diagnostic and predictive performance for PCa between AI and common clinical assessment methods based on MR images and/or clinical characteristics,thereby investigating whether AI methods are generally superior to common clinical assessment methods for the diagnosis and prediction fields of ***,we found that,in the included studies of the present study,AI methods were generally equal to or better than the clinical assessment methods for the risk assessment of PCa,such as risk stratification of prostate lesions and the prediction of therapeutic outcomes or PCa *** particular,for the diagnosis of clinically significant PCa,the AI methods achieved a higher summary receiver operator characteristic curve(SROC-AUC)than that of the clinical assessment methods(0.87 vs.0.82).For the prediction of adverse pathology,the AI methods also achieved a higher SROC-AUC than that of the clinical assessment methods(0.86 vs.0.75).Second,as revealed by the radiomics quality score(RQS),the studies included in the present study presented a relatively high total average RQS of 15.2(11.0–20.0).Further,the scores of the individual RQS elements implied that the AI models in these studies were constructed with relatively perfect and standard radiomics processes,but the exact generalizability and clinical practicality of the AI models should be further validated using higher levels of evidence,such as prospective studies and open-testing datasets.

关键词： Clinically significant prostate cancer Adverse pathology Radiomics quality score Artificial intelligence Magnetic resonance imaging

Learning-based counterfactual explanations for recommendation

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Science China(Information Sciences) 2024年第8期67卷 115-129页

作者： Jingxuan WEN Huafeng liu Liping JING jian YU School of Computer and Information Technology Beijing Jiaotong University Beijing Key Lab of Traffic Data Analysis and Mining Beijing Jiaotong University

Counterfactual explanations provide explanations by exploring the changes in effect caused by changes in cause. They have attracted significant attention in recommender system research to explore the impact of changes in certain properties on the recommendation mechanism. Among several counterfactual recommendation methods, item-based counterfactual explanation methods have attracted considerable attention because of their flexibility. The core idea of item-based counterfactual explanation methods is to find a minimal subset of interacted items(i.e., short length) such that the recommended item would topple out of the top-K recommendation list once these items have been removed from user interactions(i.e., good quality). Usually, explanations are generated by ranking the precomputed importance of items, which fails to characterize the true importance of interacted items due to separation from the explanation generation. Additionally, the final explanations are generated according to a certain search strategy given the precomputed importance. This indicates that the quality and length of counterfactual explanations are deterministic;therefore, they cannot be balanced once the search strategy is fixed. To overcome these obstacles, this study proposes learning-based counterfactual explanations for recommendation(LCER) to provide counterfactual explanations based on personalized recommendations by jointly modeling the factual and counterfactual preference. To achieve consistency between the computation of importance and generation of counterfactual explanations, the proposed LCER endows an optimizable importance for each interacted item, which is supervised by the goal of counterfactual explanations to guarantee its credibility. Because of the model's flexibility, the trade-off between quality and length can be customized by setting different proportions. The experimental results on four real-world datasets demonstrate the effectiveness of the proposed LCER over several

关键词： recommender system explainable recommendation item-based explanation counterfactual inference counterfactual explanation

SMA-origami coupling:online configuration switches and stability property modulation

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International Journal of Smart and Nano Materials 2024年第1期15卷 21-41页

作者： Hai Zhou Hongbin Fang Zuolin liu jian Xu School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghaiChina Institute of AI and Robotics Fudan UniversityShanghaiChina Yiwu Research Institute Fudan UniversityYiwuZhejiangChina

Active folding is a crucial requirement for practical applications of multi-stable origami ***,research on integrating active materials with origami structures to enable quick configuration switching and modulation of stability properties is still in its early *** advance the state-of-the-art,we designed a coupled structure comprising a stacked Miura-origami(SMO)structure and two Shape Memory Alloy(SMA)*** actuator is used for extruding the SMO structure while the other is used for retracting,thereby realizing bidirectional reversible active folding of the coupled *** the potential energy of the coupled structure shows that it can be switched between monostable and bistable by heating the SMA *** above findings are also confirmed by experiments conducted on a delicate SMO-SMA coupled structure *** activation of different actuators induces rapid configuration switching of the coupled structure,and the stability profile is qualitatively adjusted by designing the current loading profile to achieve steady-state temperature ***,this study provides a new approach to coupling origami structures with smart materials for active folding and presents a novel method to regulate the stability property of origami structures,thus promoting their practical applications.

关键词： Multistability bistable origami active folding smart material

BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)-impregnated Ni-GDC by phase-inversion as an anode of solid oxide fuel cells with on-cell dry methane reforming

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Journal of Advanced Ceramics 2024年第6期13卷 834-841页

作者： Yanya liu Jun Luo Cheng Li Bo liu Dong Yan jian Li Lichao Jia School of Materials Science and Engineering State Key Laboratory of Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074China

BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)(BCFN)in a perovskite structure is impregnated consecutively by BCFN solution and BCFN suspension into a phase-inversion prepared NiO–Gd_(0.1)Ce_(0.9)O_(2−δ)(GDC)scaffold as an anode for solid oxide fuel cells(SOFCs)with on-cell dry reforming of methane(DRM).The whole pore surface of the scaffold is covered by small BCFN particles formed by BCFN solution impregnation;the large pores near the scaffold surface are filled by BCFN aerogels with a high specific surface area produced by BCFN suspension impregnation,which act as a catalytic layer for on-cell *** reduction,the anode consists of a Ni–GDC scaffold and BCFN particles with exsolved FeNi3 *** BCFN-impregnated Ni–GDC anode has higher electrical conductivity,electrochemical activity,and resistance to carbon deposition,with which the cell shows maximum power densities between 1.44 and 0.92 W·cm^(−2) when using H_(2) and between 1.09 and 0.50 W·cm^(−2) when using CO_(2)–CH_(4) at temperatures ranging from 750 to 600℃.A stable performance at 400 mA·cm^(−2) and 700℃is achieved using 45%CO_(2)–45%CH_(4)–10%N_(2) for more than 400 h without carbon deposition,benefiting from the impregnated BCFN aerogel with a high specific surface area and water adsorbability.

关键词： aerogel solid oxide fuel cells(SOFCs) phase-inversion dry reforming of methane(DRM) carbon resistance

High-efficiency preparation of multifunctional conjugated electrospun graphene doped PVDF/CF yarns for energy harvesting and human movement monitoring in TENG textile

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Nano Research 2024年第5期17卷 4478-4488页

作者： Ting Yang Chengwei Wan Xiaoyu Zhang Tong liu Li Niu jian Fang Yuqing liu College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123China

Portable power is an effective solution to realize self-powered sensors for wearable devices,promoting future sustainable ***-based triboelectric nanogenerators(M-TENGs)have emerged as a promising technology for harvesting biomechanical energy from human motion owing to their advantages,such as simple structure,lightweight design,and efficient energy ***,the poor durability,low adaptability,and un-washability of two-dimensional membrane materials have largely hindered their application in wearable *** this study,we propose a sheath-core polyvinylidene fluoride(PVDF)/graphene(G)-carbon fiber(CF)yarn fabricated via conjugate electrospinning,comprising a commercial CF core and an electrospun graphene-doped PVDF sheath,which improves the fatigue resistance of electrospun nanofiber films under prolonged friction and keeps a high degree of *** resulting electronic textile,woven with the large-scale electrospun PVDF/G-CF yarn,demonstrates a remarkable power density of 25.5 mW·m^(-2).The tight distribution of PVDF/G nanofibers on the textile surface ensures excellent softness,washability,and ***,the electrospun PVDF/G-CF textile exhibits significant potential in pressure sensing,self-powered operation,and motion detection,making it highly suitable for wearable electronics applications.

关键词： yarn-based triboelectric nanogenerator(TENG) graphene polyvinylidene fluoride(PVDF) conjugated-electrospinning multifunctional