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Fine machining of Large-Diameter 6H-SiC Wafers

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Journal of materials Science & Technology 2006年第5期22卷 681-684页

作者： Xiufang CHEN juan li Deying ma Xiaobo HU Xiangang XU Minhua JIANG State Key Laboratory of Crystal materials Shandong UniversityJinan 250100China

Three main machining processes of large-diameter 6H-SiC wafers were introduced in this paper. These processes include cutting, lapping and polishing. Lapping causes great residual stresses and deep damage layer which can be reduced gradually with subsequent polishing processes. Surfaces prepared by mechanical polishing （MP） appeared a large number of scratches with depth of 5-8 nm. These scratches can be effectively removed by chemo-mechanical polishing （CMP）. After CMP. extremely smooth and low damage layer surface with roughness Ra=0.3 nm was obtained. Atomic force microscopy （AFM） and optical microscopy were used to observe the surface morphology of samples and a high resolution X-ray diffractometer （HRXRD） was used for the crystal lattice perfection of the subsurface region. Changes of surface residual stresses during machining processes were investigated by HRXRD.

关键词： 6H-SiC Chemo-mechanical polishing (CMP) Roughness

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Historical and real-time estimation of snow depth in Eurasia based on multiple passive microwave data

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Advances in Climate Change Research 2023年第4期14卷 537-545页

作者： li-Yun DAI li-juan ma Su-Ping NIE Si-Yu WEI Tao CHE Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China National Climate Centre China Meteorological AdministrationBeijing 1000101China University of Chinese Academy of Sciences Beijing 1000101China

Current snow depth datasets demonstrate large discrepancies in the spatial pattern in Eurasia,and the lagging updates of datasets do not meet the operational requirements of the meteorological service *** study developed a dynamic retrieval method for daily snow depth over Eurasia based on cross-sensor calibrated microwave brightness temperatures to enhance retrieval accuracy and meet the requirements of operational *** brightness temperatures were detected by microwave radiometer imager carried on the FengYun 3(FY-3)satellite and the special sensor microwave imager/sounder carried on the USA Defense Meteorological Satellite Program series satellites,which use the fewest sensors to provide the longest data and consequently introduce minimal errors during inter-sensor ***,inter-sensor calibration was conducted amongst brightness temperatures collected by the three sensors.A spatiotemporal dynamic relationship between snow depth and microwave brightness temperature gradient was then established,overcoming the large uncertainties induced by varying snow *** relationship can be utilised in FY-3 satellite data for operational service to obtain real-time snow *** generated daily snow depth dataset from 1988 to 2021 presents similar spatial patterns of snow depth to those observed in *** in situ snow depth,the overall bias and root mean square error are−2.04 and 6.49 cm,respectively,facilitating considerable improvements in accuracy compared with the Advanced Microwave Scanning Radiometer 2 snow depth product,which adopts the static *** analysis shows an overall decreasing trend from 1988 to 2021 for annual and monthly mean snow depths,demonstrating a noticeable reduction since around *** reduction in monthly mean snow depth started earlier in shallow snow months than in deep snow months.

关键词： Snow depth Passive microwave remote sensing Eurasia

Improved Region Energy Based Image Fusion Rule for Multi-focus Image Fusion

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 109-115页

作者： Chun-Hui Zhao li-juan ma Guo-Feng Shao li-Xin liu College of Information and Communication Engineering Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

In this paper,we propose a novel improved region energy based image fusion *** original images are firstly decomposed by using the lifting scheme of wavelet transform into four sub-bands:LL,LH,HL,HH,by studying principles and characteristics of the wavelet subbands,and we put emphasis on the high frequency *** HH,HL,LH sub-bands,which represent three direction of high frequency details,are weighted by different size of three direction Gaussian kernel,then the energy based image fusion rule is applied with a optional size of window,thus the activity level of high frequency subbands are obtained,followed by a local region matching degree in the corresponding direction and resolution,an activity level of low frequency subband is calculated,then perform consistency verification on the selected wavelet coefficients,by doing the inverse wavelet transform the fused image is *** performance of the proposed novel image fusion scheme is conducted and compared with a few existing image fusion algorithm,the experimental results show that the proposed method is an effective multi-focus image fusion algorithm.

关键词： lifting scheme weighted energy region matching degree consistency verification

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Researches on chemically modified electrode *** reduction of oxygen on iron porphyrin modified electrode

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Chinese Journal of Chemistry 1984年第2期2卷 95-104页

作者： DONG Shao-Jun XU li-juan ma Yue Changchun Institute of Applied Chemistry,Academia Sinica Changchun Institute of Applied Chemistry Academia Sinica

By surface organic synthesis a Fe(Ⅲ)tetra-o-aminophenyl porphyrin modified electrodewas successfully prepared on glassy carbon electrode surface through *** preparativeconditions were investigated in *** cyclic voltammetry and semidifferential neo-polarogra-phy in an acidic aqueous solution the behavior of the catalytic reduction ofoxygen on iron porphyriamodified electrode was *** on experimental results it was shown that the irreversibleprocess of 2-electron-reduction to hydrogen peroxide belongs to EC parallel catalytic process.

关键词： TAPP Researches on chemically modified electrode V.Catalytic reduction of oxygen on iron porphyrin modified electrode

HDR syndrome presented with nephrotic syndrome in a Chinese boy: A case report

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World Journal of Clinical Cases 2024年第27期12卷 6111-6116页

作者： li-juan ma Wu Yang Hong-Wen Zhang Department of Pediatrics Peking University First Hospital Ningxia Women and Children’s HospitalYinchuan 750001Ningxia Hui Autonomous RegionChina Department of Pediatric Peking University First HospitalBeijing 100034China

BACKGROUND HDR syndrome is a rare genetic disease caused by variants in the GATA3 gene and is phenotypically defined by the triad of hypoparathyroidism(H),deafness(D),and renal disease(R).Renal disorders of HDR are mainly developmental ab-normalities,although renal functional abnormalities can also be ***-phrotic syndrome or nephrotic-level proteinuria is rare in HDR ***,we report a Chinese infant with HDR syndrome who presented with early-onset nephrotic *** suggest that variants in the GATA3 gene might be asso-ciated with nephrotic syndrome.(***235 Leu),in exon 3 of the GATA3 *** We report an infant with HDR syndrome who presented with early-onset nephrotic syndrome in *** suggest that variants in the GATA3 gene might be associated with infant-onset nephrotic syndrome.

关键词： HDR syndrome Sensorineural deafness Nephrotic syndrome China Case report

Discovery of human pancreatic lipase inhibitors from root of Rhodiola crenulata via integrating bioactivity-guided fractionation,chemical profiling and biochemical assay

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Journal of Pharmaceutical Analysis 2022年第4期12卷 683-691页

作者： li-juan ma Xu-Dong Hou Xiao-Ya Qin Rong-Jing He Hao-Nan Yu Qing Hu Xiao-Qing Guan Shou-Ning Jia Jie Hou Tao Lei Guang-Bo Ge Shanghai Frontiers Science Center of TCM Chemical Biology Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai201203China Department of Endocrinology Putuo HospitalShanghai University of Traditional Chinese MedicineShanghai200062China College of Basic Medical Sciences Dalian Medical UniversityDalian116044China Qinghai Hospital of Traditional Chinese Medicine Xining810099China

Although herbal medicines(HMs)are widely used in the prevention and treatment of obesity and obesity-associated disorders,the key constituents exhibiting anti-obesity activity and their molecular mechanisms are poorly ***,we assessed the inhibitory potentials of several HMs against human pancreatic lipase(hPL,a key therapeutic target for human obesity),among which the root-extract of Rhodiola crenulata(ERC)showed the most potent anti-hPL *** this study,we adopted an integrated strategy,involving bioactivity-guided fractionation techniques,chemical profiling,and biochemical assays,to identify the key anti-hPL constituents in *** ERC fractions(retention time=12.5e35 min),obtained using reverse-phase liquid chromatography,showed strong anti-hPL activity,while the major constituents in these bioactive fractions were subsequently identified using liquid chromatography-quadrupole time-of-flight mass spectrometry(LC-Q-TOF-MS/MS).Among the identified ERC constituents,1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose(PGG)and catechin gallate(CG)showed the most potent anti-hPL activity,with pIC50 values of 7.59±0.03 and 7.68±0.23,*** investigations revealed that PGG and CG potently inhibited hPL in a non-competitive manner,with inhibition constant(Ki)values of 0.012 and 0.082 mM,***,our integrative analyses enabled us to efficiently identify and characterize the key anti-obesity constituents in ERC,as well as to elucidate their anti-hPL *** findings provide convincing evidence in support of the anti-obesity and lipid-lowering properties of ERC.

关键词： Human pancreatic lipase Rhodiola crenulata 1,2,3,4,6-Penta-O-Galloyl-β-D-glucopyranose Catechin gallate Inhibitory mechanism

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen ma Jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Efficient and Stable Photoassisted lithium-Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： ma, Zelin Wang, Shiyao ma, Zhuangzhuang li, juan Zhao, Luomeng li, Zhihuan Wang, Shiyuan Shuang, Yazhou Wang, Jiulong Wang, Fang Xia, Weiwei Jian, Jie He, Yibo Wang, Junjie Guo, Pengfei Wang, Hongqiang Northwestern Polytech Univ Ctr Nano Energy Mat State Key Lab Solidificat Proc Sch Mat Sci & Engn Xian 710072 Peoples R China NPU Shaanxi Joint Lab Graphene Xian 710072 Peoples R China Northwestern Polytech Univ Sch Mat Sci State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Engn Dept Xian 710072 Peoples R China Northwestern Polytech Univ Ctr Adv Lubricat & Seal Mat Sch Mat Sci & Engn State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Shenzhen Res & Dev Inst Shenzhen 518063 Peoples R China Shaanxi Normal Univ Key Lab Appl Surface & Colloid Chem Shaanxi Engn Lab Adv Energy Technol Shaanxi Key Lab Adv Energy DevicesSch Mat Sci & E Xian 710119 Peoples R China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries (PliBs), while there is always a request on fast carrier transport in electrochemical active photocathodes. Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals. When employed in PliBs, it was found effective for synchronously enhanced photocharge separation and transport in light charging process. Additionally, experimental photon spectroscopy, finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO2, as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact. Benefiting from these merits, several benchmark values in performance of TiO2-based photocathode applied in PliBs are set, including the capacity of 276 mah g(-1 ) at 0.2 A g(-1 )under illumination, photoconversion efficiency of 1.276% at 3 A g(-1 ), less capacity and Columbic efficiency loss even through 200 cycles. These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals

Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第01期 26-34页

作者： Yutao Zhang juan li Wei-Hong Zhu Zhiqian Guo Shanghai Key Laboratory of Functional materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

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