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Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang Yong-Qing liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-Shuai Chen li-zhi wu Meng Tian Long Chen Yi Wei liao-Yuan Song Jian li Zi-Gang wu Yun-Qian liu Xuan-Chun liu An-Qing Chen zhi-Wei liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

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Studies on absorption coefficients of dual-energy γ-rays and measur-ing error correction for multiphase fraction determination

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Nuclear Science and Techniques 2006年第2期17卷 86-91页

作者： li zhi-Biao wu Ying-Xiang li Dong-Hui Institute of Mechanics the Chinese Academy of Sciences Beijing 100080 China

In this article, principle and mathematical method of determining the phase fractions of multiphase flows by using a dual-energy γ -ray system have been described. The dual-energy γ -ray device is composed of radioactive isotopes of 241Am and 137Cs with γ -ray energies of 59.5 and 662 keV, respectively. A rational method to calibrate the absorption coefficient was introduced in detail. The modified arithmetic is beneficial to removing the extra Compton scattering from the measured value. The result shows that the dual-energy γ -ray technique can be used in three-phase flow with average accuracy greater than 95%, which enables us to determine phase fractions almost independent of the flow regime. Improvement has been achieved on measurement accuracy of phase fractions.

关键词：吸收系数相位分形双重能量多相流错误校正

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The Microstructures of Butterfly Wing Scales in Northeast of China

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Journal of Bionic Engineering 2007年第1期4卷 47-52页

作者： li-yan wu zhi-wu Han Zhao-mei Qiu Hui-ying Guan Lu-quan Ren Key Laboratory for Terrain-Machine Bionics Engineering （Ministry of Education China） School for Biological and Agricultural Engineering Jilin University （Nanling Campus） Changchun 130022 P. R. China

There are billions of tiny scales on the butterfly wings, which array regularly as the tiles on the roof. Such tilts can form various colors of the wing and afford the species many abilities to survive and propagate. Morphological experiments on the wing scales of six butterfly species living in northeast of China were conducted. By the optics microscope; the form, geometry dimension and array of the scales were observed generally. By using scanning electron microscope （SEM）, the 2D scanning and measurement were carried out and the surface micro configurations of scales were observed. The dimension and microstructure characteristics of the cross section of single scale were achieved through transmission electron microscope （TEM）. Finally, by using 3D software, three 3D models were described and the 3D visual effect was achieved. This work can put forward a basic method for the future study on the morphology of biological microstructure.

关键词： butterfly wing scale microstructure microscope

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Simulation of jet-flow solid fraction during spray forming

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 657-669页

作者： Zi-qiang Pi Xin Lu Yuan wu Lu-ning Wang Cheng-chang Jia Xuan-hui Qu Wei Zheng li-zhi wu Qing-li Shao Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Heye Special Steel Co. Ltd. Shijiazhuang 052165 China

A numerical model was developed to simulate the jet-flow solid fraction of W18Cr4 V high-speed steel during spray forming. The whole model comprises two submodels: one is an individual droplet model, which describes the motion and thermal behaviors of individual droplets on the basis of Newton's laws of motion and the convection heat transfer mechanism; the other is a droplet distribution model, which is used to calculate the droplet size distribution. After being verified, the model was used to analyze the effects of parameters, including the initial gas velocity, deposition distance, superheat degree, and the ratio of gas-to-metal mass flow rates, on the jet-flow solid fraction. Finally, an equation to predict the jet-flow solid fraction directly and conveniently according to the parameters was presented. The values predicted by the equation show good agreement with those calculated by the numerical model.

关键词： modeling steel spray forming solid fraction

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Analysis of a FBG sensing system with transverse uniform press by using genetic algorithm

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Optoelectronics Letters 2008年第2期4卷 121-125页

作者： TENG Feng-cheng YIN Wen-wen wu Fei li zhi-quang wu Ti-hua Institute of Automatic Instrument College of Electric Engineering Yanshan University Qinhuangdao 066004 China

An analytical method in a quasi-static fiber grating sensing system under transverse uniform press is proposed based on genetic algorithm The effect of population size, generations, crossover ratio and mutation ratio to genetic algorithm, and the optimization parameters of genetic algorithm were given. The relevant experimental system is constructed. The simulation and experiments show that the analytical method proposed can be applied to analyze the reflective spectra of the quasistatic FBG sensing system at transverse uniform press, the strain measurement with high-precision of 0.91% can be realized

关键词： FBG 感觉系统遗传算法光纤元件

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A Hybrid Signal Processing Method Combining Mathematical Morphology and Walsh Theory for Power Quality Disturbance Detection and Classification

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 584-592页

作者： zhi Ding Tianyao Ji Mengshi li Q.H.wu School of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

In this paper, a novel signal processing method combining mathematical morphology (MM) and Walsh theory is proposed, which uses Walsh functions to control the structuring element (SE) and MM operators. Based on the Walsh-MM method, a scheme for power quality disturbances detection and classification is developed, which involves three steps: denoising, feature extraction and morphological clustering. First, various evolution rules of Walsh function are used to generate groups of SEs for the multiscale Walsh-ordered morphological operation, so the original signal can be denoised. Next, the fundamental wave of the denoised signal is suppressed by Hadamard matrix;thus, disturbances can be extracted. Finally, the Walsh power spectrum of the waveform extracted in the previous step is calculated, and the parameters of which are taken by morphological clustering to classify the disturbances. Simulation results reveal the proposed scheme can effectively detect and classify disturbances, and the Walsh-MM method is less affected by noise and only involves simple calculation, which has a potential to be implemented in hardware and more suitable for real-time application.

关键词： Hadamard matrix mathematical morphology morphological clustering power quality disturbance Walsh theory

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Wettability regulation from superhydrophilic to superhydrophobic via nanosecond laser ablation

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Science China(Technological Sciences) 2024年第6期67卷 1829-1841页

作者： CHEN zhi wu zhiCheng ZHANG GuoJun li DongHui HAN Fenglin State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha410083China Guangdong Provincial Key Laboratory of Manufacturing Equipment Digitization Guangdong HUST Industrial Technology Research InstituteDongguan523808China China Harzone Industry Corp. Ltd.Wuhan430299China

Metal surfaces play a crucial role in numerous applications,from self-cleaning and anti-icing to anti-fogging and oil-water *** regulation of their wettability is essential to enhance their performance in these *** paper proposes a multi-state regulation method for metal surface wettability,leveraging nanosecond laser *** creating non-uniform microstructures on a metal surface,the contact area between the solid and liquid phases can be increased,resulting in the attainment of superhydrophilic properties(contact angle(CA),ranging from 4.6°to 8.5°).Conversely,the construction of uniform microstructures leads to a decreased solid-liquid contact area,thereby rendering the metal surface hydrophilic(CA=12.2°–53°).Furthermore,through heat treatment on a surface with uniform microstructures,organic matter adsorption can be promoted while simultaneously reducing surface *** process results in the metal surface acquiring hydrophobic properties(CA=92.1°–133.5°),facilitated by the“air cushion effect.”Building on the hydrophobic surface,stearic acid modification can further reduce surface energy,ultimately bestowing the metal surface with superhydrophobic properties(CA=150.1°–152.7°,and sliding angle=3.8°).Performance testing has validated the durability and self-cleaning effectiveness of the fabricated superhydrophobic surface while also highlighting the excellent anti-fog performance of the superhydrophilic *** findings strongly indicate the immense potential of these surfaces in various engineering applications.

关键词： nanosecond laser ablation surface wettability superhydrophobic superhydrophilic

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Prmt7 regulates epiboly by facilitating 2-OST and modulating actin cytoskeleton

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分子细胞生物学报:英文版 2015年第5期7卷 489-491页

作者： wu-Wen Zhang Yun-Bin Zhang Xin-Xi Zhao Ye Hua zhi-li wu Yuan-Chang Yan Yi-Ping li State Key Laboratory of Cell Biology Shanghai Key Laboratory for Molecular AndrologyInstitute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina

Dear Editor,Epiboly,the thinning and spreading of blastoderm over the yolk cells,is the first morphogenetic movement in *** of zebrafish epiboly have provided insights into basic cellular properties and mechanisms of ... 详细信息

关键词： morphogenesis fish yolk

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Paroxysmal Kinesigenic Dyskinesia:Genetics and Pathophysiological Mechanisms

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Neuroscience Bulletin 2024年第7期40卷 952-962页

作者： Jiao-Jiao Xu Hong-Fu li zhi-Ying wu Department of Medical Genetics and Center for Rare Diseases The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Neurology in the Second Affiliated Hospital Key Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou 310009China

Paroxysmal kinesigenic dyskinesia(PKD),the most common type of paroxysmal movement disorder,is characterized by sudden and brief attacks of choreoathetosis or dystonia triggered by sudden voluntary *** is mainly caused by mutations in the PRRT2 or TMEM151A *** exact pathophysiological mechanisms of PKD remain unclear,although the function of PRRT2 protein has been well characterized in the last *** on abnormal ion channels and disturbed synaptic transmission in the absence of PRRT2,PKD may be channelopathy or synaptopathy,or *** addition,the cerebellum is regarded as the key pathogenic *** depolarization in the cerebellum is tightly associated with dyskinetic ***,in PKD,other than the cerebellum,the role of the cerebrum including the cortex and thalamus needs to be further investigated.

关键词： Paroxysmal kinesigenic dyskinesia PRRT2 TMEM151A Genetics Pathophysiological mechanisms

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Burning surface formation mechanism of laser-controlled 5-aminotetrazole propellant

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Defence Technology（防务技术） 2023年第7期25卷 48-59页

作者： Nian-bai He Rui-qi Shen Luigi T.DeLuca li-zhi wu Wei Zhang Ying-hua Ye Yue-ting Wang School of Chemical Engineering Nanjing University of Science and Technology210094JiangsuChina Institute of Space Propulsion Nanjing University of Science and Technology210094JiangsuChina Sichuan Huachuan Industries Corporation 610106SichuanChina Space Propulsion Laboratory(Ret) Department of Aerospace Science and TechnologyPolitecnico di Milano20156MilanItaly

As an innovative propulsion technique, combustion mechanism of laser-augmented chemical propulsion has still to be ascertained. Benefiting from high nitrogen content and thermal stability, 5-aminotetrazole is a suitable ingredient for LACP. Under a flowing nitrogen environment, two kinds of unique burning surfaces were observed to occur for 5-ATZ, used as a single reacting propellant ingredient with the addition of carbon, under laser ablation. Both surfaces are hollow structures and differ by the possible presence of edges. Using micro computed tomography, the 3D perspective structures of both surfaces were revealed. Resorting to various characterization methods, a unified formation mechanism for both surfaces is proposed. This mechanism specifically applies to laser ablation, but could be crucial to common burning mechanisms in LACP.

关键词： 5-Aminotetrazole(5-ATZ) Laser-augmented chemical propulsion (LACP) Combustion mechanism Burning surface Micro computed tomography(MicroCT)

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