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Mesoproterozoic biomineralization:Cyanobacterium-like filamentous siderite sheaths~1.4 Ga

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Journal of Palaeogeography 2023年第3期12卷 384-400页

作者： Dong-jie tang Xiao-Ying Shi Xi-Qiang Zhou Robert Riding State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences(Beijing)Beijing 100083China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Earth and Planetary Sciences University of TennesseeKnoxvilleTN 37996-1526USA

Biomineralization was a key development in a wide variety of organisms,yet its history prior to the Ediacaran remains poorly *** this paper,we describe~1420-1330 million year old microscopic tubes preserved as siderite(FeCO_(3)).In size and shape these tubes closely resemble cyanobacterial sheaths forming mineralized *** consider two competing explanations for their ***,the tubes and associated sediment were originally composed of Ca-carbonate that was subsequently replaced by *** this case,siderite mineralization was early,but post-mortem,as in early silicification,and preferentially preserved the more resilient ***,no relict calcite is ***,the Fe-carbonate mineralogy of the tubes and sediment is *** this case,photosynthetic oxygen may have precipitated Fe-oxyhydroxide that was promptly converted to siderite by dissimilatory iron reduction(DIR).Primary siderite mineralization of cyanobacteria has not been described *** explanations link photosynthetic processes to preferential sheath mineralization during the life of the cyanobacteria,as observed in present-day calcified *** process might include CO_(2)-concentrating mechanisms(CCMs)linked to relatively low levels of atmospheric CO_(2),consistent with empirical estimates of mid-Proterozoic CO_(2)levels based on paleosols and weathering *** either case,these cyanobacterium-like fossils preserved in siderite provide an early example of biomineralization and suggest the interactive in-fluences of both metabolic processes and ambient seawater chemistry.

关键词： Xiamaling Formation Siderite Ferruginous Dissimilatory iron reduction(DIR) Iron formation(IF) CO_(2)-concentrating mechanism(CCM)

Nyström kernel algorithm based on least logarithmic hyperbolic cosine loss

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Journal of Electronic Science and Technology 2023年第3期21卷 82-93页

作者： Shen-jie tang Yu tang Xi-Feng Li Bo Liu Dong-jie Bi Guo Yi Xue-Peng Zheng Li-Biao Peng Yong-Le Xie School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu611731China Shanghai Spaceflight Precision Machinery Institute Shanghai201600China

Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning *** is noted that the effectiveness of KAFs is highly reliant on a rational learning *** this,the logarithmic hyperbolic cosine(lncosh)criterion with better robustness and convergence has drawn attention in recent ***,existing lncosh loss-based KAFs use the stochastic gradient descent(SGD)for optimization,which lack a trade-off between the convergence speed and *** recursion-based KAFs can provide more effective filtering ***,a Nyström method-based robust sparse kernel recursive least lncosh loss algorithm is derived in this *** via measures and synthetic data against the non-Gaussian noise confirm the superiority with regard to the robustness,accuracy performance,and computational cost.

关键词： Kernel adaptive filter(KAF) logarithmic hyperbolic cosine (lncosh)loss Nyström method Recursive

Myeloid sarcoma as the only manifestation in a rare mixed lineage leukemia-fusion-driven acute myeloid leukemia:A case report

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World Journal of Clinical Cases 2023年第25期11卷 6000-6004页

作者： Sheng-jie tang Qi-Guo Zhang The First Clinical Medical College of Xuzhou Medical University Xuzhou 221004Jiangsu ProvinceChina Department of Hematology Chuzhou Hospital affiliated to Anhui Medical UniversityChuzhou 239001Anhui ProvinceChina

BACKGROUND The mixed lineage leukemia(MLL)-eleven-nineteen lysine-rich leukemia(ELL)fusion gene is a rare occurrence among the various MLL fusion *** present the first case in which myeloid sarcoma(MS)was the only manifestation of adult MLL-ELL-positive acute myeloid leukemia(AML).CASE SUMMARY We report a case of a 33-year-old male patient who was admitted in June 2022 with a right occipital area mass measuring approximately 7 cm×8 *** work was *** patient underwent right occipital giant subscalp mass excision and incisional flap *** was positive for myeloperoxidase,CD43 and CD45 and negative for CD3,CD20,CD34,and *** bone marrow aspirate showed hypercellularity with 20%*** cytometry showed that myeloblasts accounted for 27.21%of the nucleated cells,which expressed CD33,CD38,and *** karyotype was 46,XY,t(11,19)(q23;p13.1),-12,+mar/46,***-generation sequencing showed a fusion of MLL exon 7 to exon 2 of ELL.A diagnosis of MLL-ELL-positive AML(M2 subtype)with subcutaneous MS was *** MLL-ELL-positive AML with MS is a rare clinical *** research is needed to elucidate the molecular mechanisms of the pathogenesis of MS.

关键词： Myeloid sarcoma Acute myeloid leukemia Mixed lineage leukemia-elevennineteen lysine-rich leukemia Transplantation Case report

Styrene/Butadiene Copolymer Synthesized by Reactive Extrusion

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Chinese Journal of Polymer Science 2015年第8期33卷 1096-1103页

作者： Ji-ming Wang Bo Chen Sheng-jie tang Dong Shan 郑安呐 Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and Technology Department of Mechanical Engineering University of Houston

In this study, we present a method to synthesize styrene-butadiene copolymer, using anionic polymerization in a co-rotating closely intermeshing twin-screw extruder. The weight content of polybutadiene in these copolymers was above 50% although in the past studies it had been possible to accomplish levels higher than 30%. ^1H-NMR and GPC show that the molecular structure of the two polymers is different due to different feeding method. In terms of the structure of the polymerized products, the mechanism of polymerization in the bulk polymerization is discussed. TEM and DMA show that two phases in the block copolymer are completely incompatible, leading to sharp phase separation, while the case is complicated in the copolymer through the mixture feeding. Traditionally, styrene-butadiene rubber is mainly synthesized by solution polymerization. Reactive extrusion in this paper provides a possibility to synthesize these products in an environmentally friendly way.

关键词： Reactive extrusion Styrene Butadiene Anionic polymerization.

Career Map: visualizing career trajectory

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Science China(Information Sciences) 2018年第10期61卷 247-249页

作者： Kan WU jie tang Zhou SHAO Xinyi XU Bo GAO Shu ZHAO Department of Computer Science and Technology Tsinghua University School of Computer Science and Engineering Nanjing University of Science and Technology International School Beijing University of Posts and Telecommunications School of Computer Science and Technology Anhui University

This study introduces a system named Career Map that visualizes a scholar’s career trajectory. As an online demonstration of Career Map, we have shown the visualization result by Career Map for the AMiner 2016 most influential scholars in machine learning (ML)1). Each trajectory path on the map represents the movement of a scholar between different places (affiliations). The heatmap reveals the geographic distribution of the most influential ML scholars; a larger hotspot means a larger immigration of scholars into an affiliation. The right sidebar is a list of all scholars. When the user selects (clicks on) a scholar, the trajectory path of

关键词： Career Map visualizing career trajectory Figure

Spatial distribution of soil erosion and its impacts on soil productivity in Songnen typical black soil region

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International Soil and Water Conservation Research 2023年第4期11卷 649-659页

作者： Yun Xie jie tang Yan Gao Zhijia Gu Gang Liu Xiaoyu Ren Department of Geographic Science Faculty of Arts and SciencesBeijing Normal University at ZhuhaiZhuhai519087China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875PR China Songliao Water Resources Commission Ministry of Water ResourcesChangchunJilin130021PR China Key Laboratory for Synergistic Prevention of Water and Soil Environmental Pollution School of Geographic SciencesXinyang Normal UniversityXinyang464000PR China

Soil erosion is an important reason for land *** black soil region of Northeast China is the main grain production base in China,however,the black soil productivity in this region is at risk and unsustainable now because there was few soil conservation measures in nearly 100 years of *** assess the impact of erosion on land productivity,both 210 sampling points for ^(137)Cs measurement and 112 sampling points for soil profile features were laid out on cultivated land of Songnen typical black soil region in combination with the 2010 China land use *** current soil erosion/deposition rate and land productivity index PI were calculated over the study area,and then the PI values were predicted erosion by 20,50,100,and 200 years without soil and water conservation measures based on the current erosion rate and soil profile *** results showed that the average soil erosion rate of cultivated land in the study area was 705.8 t/(km^(2)·a),and 77.0%of the cultivated land had soil erosion rate larger than the soil loss tolerance of 200 t/(km^(2)·a).Spatially,the soil erosion rate in the northern region was greater than that in the southern region significantly,which was mainly affected by slope *** relationship between soil erosion rate(SL)and slope steepness(θ)in degree was established according to the results of ^(137)Cs measured at 210 sample points:SL=556.4*θ or SL=0.464*θin mm/a(given soil bulk density is 1200 kg/m^(3)).The current mean value of PI for cultivated land was 0.59,decreasing significantly from north to south,which was mainly influenced by organic matter *** predicted PI values decreased significantly with the increase of erosion years in the northern *** is related to the topography of rolling and hills in the northern area with a greater soil loss rate,leading to a rapid decrease of organic matter content and the increase of sand content in the topsoil in the *** spatial distributions

关键词： Soil erosion Land productivity PI model Soil loss rate Black soil region

DC Motor Speed Control Based on System Identification and PID Auto Tuning 36

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DC Motor Speed Control Based on System Identification and PI...

Walking Cations: Transition-Metal Free Benzyl Cation-Triggered sp^(2) C—H Phosphorylation and Etherification

第36届中国控制会议

作者： Wei-jie tang Zhen-Tao Liu Qian Wang School of Industrial Automation Beijing Institute of Technology School of Automation China University of Geosciences Hubei key Laboratory of Advanced control and Intelligent Automation for Complex Systems

ISBN: (纸本)9781538629185

Speed control mode of a DC motor without knowing the specific parameters of the motor is *** approximate mathematical model of the control system is obtained by the system identification when the output of the system is measured by loading the specific input *** PID control algorithm is adopted and the P,I,and D parameters are obtained by auto *** in the loop（HIL） experiments are carried out on MATLAB and Arduino platform,in which the experimental results demonstrate the feasibility of the proposal.

关键词： DC motor System Identification PID control HIL Experiment Automatic Code Generation

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Chinese Journal of Chemistry 2022年第24期40卷 2933-2938页

作者： Kuan Liu Bin Song Qi Dang Long Liu jie tang Tianzeng Huang Chunya Li Zhi tang Tieqiao Chen Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources Hainan Provincial Key Lab of Fine ChemHainan Provincial Fine Chemical Engineering Research CenterHainan UniversityHaikouHainan570228 China

A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.

关键词： Transition metal-free Cation migration Site-selectivity Phosphorylation Etherification

A HfC nanowire point electron source with oxycarbide surface of lower work function for high-brightness and stable field-emission

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Nano Research 2020年第6期13卷 1620-1626页

作者： Shuai tang jie tang Ta-wei Chiu Wataru Hayami Jun Uzuhashi Tadakatsu Ohkubo Fumihiko Uesugi Masaki Takeguchi Masanori Mitome Lu-Chang Qin National Institute for Materials Science TsukubaIbaraki305-0047Japan Graduate School of Pure and Applied Science University of TsukubaTsukubaIbaraki305-8857Japan Department of Physics and Astronomy University of North Carolina at Chapel HillChapel HillNC27599-3255USA

Electric field-induced point electron source is highly demanded for microscopy,spectroscopy,lithography,X-ray tubes,microwave devices,and data ***,the instability in emission current and requirement of ultrahigh vacuum have often limited its extensive *** we report a single-crystalline HfC nanowire with oxycarbide emission surface for stable electron emission at 50 nA with fluctuations less than 1%in a vacuum of 4×10^−7 *** emitter has a low work function of 2.5 eV measured by the field emission Fowler-Nordheim curve and it is in good agreement with density functional theory(DFT)*** energy spread is in a range of 0.21–0.26 eV with a corresponding reduced brightness 1.95×10^11−3.81×10^11 A·m^−2·sr^−1·V^−*** HfC nanowire with oxycarbide emission surface is a qualified candidate for the next-generation electron source with high brightness,large current,and low energy spread.

关键词： hafnium carbide oxycarbide nanowire electron emission field emission