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Porous Single-Crystalline Monolith to Enhance Catalytic Activity and Stability

Research 2022年第4期2022卷 347-358页

作者： xiaoyan yu Fangyuan Cheng Xiuyun Duan Kui Xie Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China University of Chinese Academy of Sciences Bejing 100049China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108 FujianChina Key Laboratory of Design e Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China

Engineering the catalytic activity and stability of materials would require the identification of the structural features that can tailor active sites at *** single crystals combine the ordered lattice structures and disordered interconnected pores,and they would therefore provide the advantages of precise structure features to identify and engineer the active sites at ***,we fabricate porous single-crystalline vanadium nitride(VN)at centimeter scale and further dope Fe(Fe0.1V0.9N)and Co(Co0.1V0.9N)in lattice to engineer the active sites at *** demonstrate that the active surface is composed of unsaturated coordination of V-N,Fe-N,and Co-N structures which lead to the generation of high-density active sites at the porous single-crystalline monolith *** interconnected pores aid the pore-enhanced fluxion to facilitate species diffusion in the porous *** the nonoxidative dehydrogenation of ethane to ethylene,we demonstrate the outstanding performance with ethane conversion of 36%and ethylene selectivity of 99%at 660°*** stability as a result of their single-crystalline structure,the monoliths achieve the outstanding performance without degradation being observed even after 200 hours of a continuous operation in a monolithic *** work not only demonstrates the effective structural engineering to simultaneously enhance the stability and overall performance for practically useful catalytic materials but also provide a new route for the element doping of porous single crystals at large scale for the potential application in other fields.

关键词： surface crystalline stability

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Mineral association and graphite inclusions in nephrite jade from Liaoning, northeast China: Implications for metamorphic conditions and ore genesis

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Geoscience Frontiers 2019年第2期10卷 425-437页

作者： Cun Zhang xiaoyan yu Tianlong Jiang School of Gemology China University of Geosciences (Beijing)

The Liaoning Province in the northeastern part of the North China Craton(NCC) hosts several tremolite jade(nephrite) deposits. Here we investigate the Sangpiyu tremolite jade deposit where the relationship between abundant graphite inclusions within the jade remains enigmatic. We employ petrography, electron probe microanalysis, X-ray-diffraction, and Raman spectroscopy to characterize the tremolite jade and its inclusion minerals. The Sangpiyu jade is predominately composed of tremolite with minor calcite, dolomite, serpentine, titanite, zoisite, allanite, chlorite,apatite, chromite and graphite. Raman spectroscopy of graphite inclusions shows that the D1/G intensity ratio ranges from 0.78 to 0.88 in deep green samples and from 0.05 to 0.23 in dark green samples. The ranges of D1/(D1 + G) integral area ratio for these types are from 0.0548 to 0.3037 and 0.5528 to 0.7355 respectively. The formation temperature of graphite inclusions in the dark green tremolite jade is computed as 549.8 ℃, whereas that for the deep green sample is about343.2 ℃. Our results suggest that the jade formation occurred in a multi-stage process through the action of hydrothermal fluids and metamorphism possibly in a subduction-related setting at moderate to high temperatures.

关键词： Tremolite jade Petrology and Raman spectroscopy Graphite Sangpiyu North China

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Effects of sludge characteristics on electrical resistance and energy consumption during electro-dewatering process

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Journal of Environmental Sciences 2021年第3期33卷 339-350页

作者： Li Sha xiaoyan yu Zhangxiang Wu Xingxin Liu Shuting Zhang School of Environmental Science and Engineering Tianjin UniversityTianjin 300354China School of Environmental and Safety Engineering Taiyuan Institute of TechnologyTaiyuan 030008China

The increase of electrical resistance(ER)and energy consumption(EC)during the later stage of dewatering is a major problem hindering the development of electro-dewatering(EDW)*** the variations of sludge characteristics are significant during the EDW process,the relationships between sludge characteristics and ER and EC during EDW remain *** this study,the effects of moisture content(MC),thickness,pH,conductivity,zeta potential,temperature,and gas volume on the ER and EC during the EDW process were statistically investigated using correlation and multiple linear regression ***,the results showed that the ER of the sludge near the anode was primarily affected by pH,whereas the sludge near the cathode was primarily affected by the MC and ***,sludge temperature and conductivity were the most reliable indicators to predict the EC near the anode and cathode,*** results of this study provide theoretical guidance useful for solving the increase of ER and EC during the later stage of the EDW process.

关键词： Sludge Electro-dewatering Electrical resistance Energy consumption Multiple linear regression

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Doubly selective fading channel estimation in MIMO OFDM systems

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Science in China(Series F) 2005年第6期48卷 795-807页

作者： yu xiaoyan WANG Jiaqing YANG Luxi HE Zhenya Department of Radio Engineering Southeast University Nanjing 210096 China

High data transmission rates and high mobility give rise to time- and frequency-selectivity in wireless communication channels. This paper investigated time and frequency doubly selective channel estimation using pilot tones among Multi-Input Multi-Output （MIMO） orthogonal frequency division multiplexing （OFDM）. Firstly, a complex exponential basis expansion channel model （BECM） was introduced to represent doubly selective channel during an OFDM symbol period; then, based on BECM, an effective MIMO-OFDM doubly selective channel estimation method was presented; finally, the optimality in designing pilot tones parameters was done according to the minimization of channel estimation MSE, mainly including the number, the placement and the structure of pilot tones. Simulation results show that the proposed estimation method has good performance in doubly selective channel scenarios and confirms the theoretical analysis findings.

关键词： MIMO-OFDM doubly selective channels channel estimation basis expansion channel model.

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How Does ESG Performance Impact Corporate Financing Costs?An Empirical Study in China

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Journal of Systems Science and Information 2024年第2期12卷 229-244页

作者： Wei LI Mei MEI xiaoyan yu Jiahao WANG Tiangeng (Becky) GENG School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Institute of Medical Information&Library Chinese Academy of Medical SciencesBeijing 100005China Business and Management Royal HollowayUniversity of LondonSurrey TW200EXUK Krieger School of Arts and Sciences Johns Hopkins UniversityBaltimore MD 21218USA

In the background of the green transformation of the economy and society,the ESG performance of enterprises has been paid more and more attention in the investment ***,previous studies have inadequately explored how the ESG performance affects corporate financing *** on the information asymmetry theory,this paper analyzes the impact mechanism of ESG performance on corporate financing ***,taking 1044 A-share listed companies in2016–2020 as a sample,through the sorting and analysis of ESG report disclosure and rating data,the company’s ESG performance indicators are obtained,and an empirical model is built to test the relationship between ESG performance and corporate financing *** paper constructs a panel regression model using ESG rating data and corporate financial data and finds that in the overall sample,the higher the ESG performance,the lower the equity financing cost;The higher the ESG performance,the lower the debt financing *** addition,it also discussed the moderating effect of enterprise scale and media attention on the impact of ESG performance on enterprise financing *** empirical results show that the influence of company size on ESG performance on financing costs has a moderating effect and a positive moderating effect.

关键词： ESG performance financing cost corporate heterogeneity media attention

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Fabrication and properties of ultraviolet photo-detectors based on SiC nanowires

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Science China(Physics,Mechanics & Astronomy) 2012年第7期55卷 1168-1171页

作者： PENG Gang ZHOU YingQiu HE YanLan yu xiaoyan LI GongYi School of Science National University of Defense TechnologyChangsha 410073China

A new type of ultraviolet photo-detectors （UVPDs） based on a bundle of highly aligned SiC nanowires was fabricated and the photo-electric properties of the UVPDs including 1-V characteristics and time response were studied in this work. SiC nan- owires were prepared by pyrolysis of a polymer precursor with ferrocene as the catalyst by a CVD route. The diameters of SiC nanowires varied from 100 to 200 nm while they were some centimeters long and the SiC nanowires were with zinc blended cubic form （β-SiC） tested by X-ray diffraction. A bundle of nanowires was fixed onto two legs＇ base by conductive silver paste to form the UVPDs. The electrical measurement of the device showed a significant increase of current when the device was exposed to 254 nm UV light, and the rising time of the device is very short, but the falling time is relatively long. Our results show that the UVPDs based on SiC nanowires have excellent electrical and optical properties which can be potentially applied.

关键词： ultraviolet photo-detectors (UVPDs) SiC nanowires photo-electric property

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Research on the Characteristics of Private Colleges Singleparent Family College Students and the Education Approaches

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International Journal of Technology Management 2016年第7期 24-26页

作者： xiaoyan yu shandong Yingcai University JinanShandong250104 China

In this paper, we conduct research on the characteristics of the private college single-parent family college students and theeducation approaches. Along with the rapid development of society and economy, especially the social employment situation is increasingly serious, and the widening of the gap between rich and poor, single-parent college students’ psychological pressure so will continue to increasethe psychological quality will be more vulnerable. According to the latest census fi gures show that single-parent college student psychological pressure increases year by year, and that will continue to rise, and to cause a decline in overall psychological quality. Private colleges of modern single-parent students education and training has its own particularity, this topic to run by the local characteristics of single-parent students in colleges and universities and private colleges education management and the analysis of this paper analyzes the particularity of the talent *** on this basis, this paper proposes the new idea on the issues that will be meaningful.

关键词： Private Colleges Single-parent Family Education Approaches Students.

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A guide to use fluorinated aromatic bulky cations for stable and high-performance 2D/3D perovskite solar cells:The more fluorination the better?

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Journal of Energy Chemistry 2022年第1期31卷 179-189,I0006页

作者： Lei Wang Qin Zhou Zilong Zhang Wenbo Li Xiaobing Wang Qi ng Tian xiaoyan yu Ting Sun Jihuai Wu Bao Zhang Peng Gao School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina Laboratory for Advanced Functional Materials.Xiamen Institute of Rare Earth Materials Haixi InstituteChinese Academy of SciencesXiamen 361021FujianChina College of Materials Science and Engineering Huaqiao University361021 XiamenFujianChina

While serious stability issues impede the commercialization of perovskite solar cells(PSCs),two-dime nsional(2D)perovskites based on fluorinated bulky cations have emerged as more intrinsically stable ***,the influence of fluorination degree of the bulky aromatic cation on the per-formance of resulting PSCs has not been ***,2D perovskites(FxPEA)_(2)PbI_(4)(x=1,2,3,5)are grown in situ on the surface of the three-dime nsion al(3D)perovskite and dem on strate effective passivation of the surface defects of 3D *** power conversion efficiency(PCE)of the optimized devices were boosted from 20.75%for the control device to 21.09%,22.06%,22.74%and 21.86%for 2D/3D devices treated with 4-fluorophenethylamine iodide,3,5-difluorophenylethylamine iodide,2,4,5-trifluoroethylphenylethylamine iodide,and 1,2,3,4,5-pentafluorophenylethylamine iodide,*** firstly reported two unexplored RP-type layered perovskites with F_(2)PEAI and F_(3)PEAI as bulky *** combined experimental and theoretical analysis revealed the reasons behind the various morphology,device performances,dynamic behavior,and humidity *** best performing F_(5)PEAI-treated device retaining 95.0%of its initial PCE under ambient atmosphere(with RH of 60%±5%)without encapsulation for 300 h *** work provides useful guidance for selecting fluorinated bulky cations with different molecular electronic properties,which will play an essential role in further improving the performance/stability of PSCs for the sake of further commercialization.

关键词： 2D perovskite Fluorinated spacer cation Perovskite solar cells Passivation Stability

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Frequency-specific abnormalities in regional homogeneity among children with attention deficit hyperactivity disorder: a resting-state f MRI study

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Science Bulletin 2016年第9期61卷 682-692页

作者： xiaoyan yu Binke yuan Qingjiu Cao Li An Peng Wang Alasdair Vance Timothy J.Silk yufeng Zang yufeng Wang Li Sun Peking University Sixth Hospital/Institute of Mental Health Key Laboratory of Mental Health Ministry of Health Peking University Center for Cognition and Brain Disorders Hangzhou Normal University Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments Academic Child Psychiatry Unit Department of PediatricsUniversity of Melbourne Royal Children’s Hospital Developmental Imaging Murdoch Childrens Research InstituteDepartment of Pediatrics University of Melbourne

Although many functional magnetic resonance imaging(f MRI) studies have investigated the neurophysiology of attention deficit hyperactivity disorder(ADHD),the existing studies have not yielded consistent *** may be related to the different properties of different frequency bands. To investigate the frequency-specific regional homogeneity(Re Ho) of spontaneous neural activities in ADHD, the current study used resting-state f MRI to explore the Re Ho properties of five frequency bands, slow-5(0.01–0.027 Hz), slow-4(0.027–0.073 Hz),slow-3(0.073–0.198 Hz), slow-2(0.198–0.25 Hz) and the extra-low frequency(0–0.01 Hz), in 30 drug-naive boys with ADHD and 30 healthy controls. Compared with controls, the ADHD group showed decreased Re Ho in the default mode network(DMN) including the medial prefrontal cortex and precuneus, middle frontal gyrus and angular gyrus. ADHD patients also showed increased Re Ho in the posterior cerebellum. Significant interactions between frequency band and group were observed predominantly in the dorsolateral prefrontal and parietal cortices, orbital frontal cortex, supplementary motor area,inferior occipital gyrus, thalamus and anterior *** particular, we found that the between-group difference in the extra-low frequency band(0–0.01 Hz) seemed to be greater than that in the other frequency bands for most brain regions. The findings suggest that ADHD children display widespread abnormalities in regional brain activity,particularly in the DMN and attention network, and these abnormalities show frequency specificity.

关键词： Attention deficit hyperactivity disorder(ADHD) Resting state Regional homogeneity(ReHo) Frequency-specific

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Comparative analysis of domestic and professional women image in modem literature

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International Journal of Technology Management 2013年第12期 3-5页

作者： yu Chen xiaoyan Fan Zhaotong University ZhaotongYunnan657000 China

Comparative analysis of domestic and professional women image in modem literature in the impression of Chinese classical poetry that women are always given the weak, meek attitude. Virtuous, dignified and elegant is the good to requirements right woman, whether going shyly and sniffing the plum, or the lady laughing as if daring according to water lines and being. When faced with love, women in classical literature mostly appeared as the role of attachment or victims, their character sketched vain traces as a faint smudge of ink.

关键词： Professional woman female consciousness literature about

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