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Acta Geochimica 2022年第5期41卷 789-793页

作者： Zongyi Wu Jian sun xiaowei Li Xiangkun Zhu Institute of Geology MNR Key Laboratory of Deep-Earth DynamicsChinese Academy of Geological Sciences MNR Key Laboratory of Isotope Geology100037 BeijingPR China State Key Laboratory of Geological Processes and Mineral Resources School of Earth Science and ResourcesUniversity of Geosciences100083 BeijingChina

As a powerful tracer in high-temperature geochemistry,Fe isotopes have been studied for their behaviour during fl uid exsolution and evolution related to felsic magma system,but that for carbonatite magma system remains unknown.Here we study the Fe isotope fractionation behaviour during fenitization–processes that widely occur associated with carbonatite or alkaline intrusions.Nine fenite/carbonatite samples from carbonatite dykes at Bayan Obo area are analyzed for their Fe isotope compositions as well as elemental compositions.Combined with previous reported carbonatite δ^(56)Fe data,the results show that carbonatites range from-0.35‰to 0.28‰,with an average of-0.10‰in δ^(56)Fe values,while fenites range from-0.17‰to 0.30‰,with an average of 0.11‰in δ^(56)Fe values.This indicates that fenitizing fl uids exsolved from carbonatite melts are enriched in heavier Fe isotopes.Such a Fe isotope fractionation trend is diff erent from that for fl uid exsolution from felsic magmatism.δ^(56)Fe values in fenites are negatively correlated with indicators of fenitization intensity such as(Na+K),Ti,Ba,Th,Nb,U or Pb abundances,likely refl ecting that Fe isotopes fractionate during the evolution of the fenitizing fl uids.Thus,Fe isotopes are a valuable tool for tracing fl uid exsolution and evolution relevant to carbonatite magmatism and related metal mineralization.

关键词： Iron isotopes Fenitization Fluid exsolution Carbonatite Bayan Obo

Sedimentary and reservoir architectures of MB1-2 sub-member of Middle Cretaceous Mishrif Formation of Halfaya Oilfield in Iraq

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Petroleum Exploration and Development 2020年第4期47卷 762-772页

作者： sun Wenju QIAO Zhanfeng SHAO Guanming SUN Xiaowei GAO Jixian CAO Peng ZHANG Jie CHEN Wangang PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China China United Coalbed Methane Corp. Ltd.Beijing 100011China PetroChina Hangzhou Research Institute of Geology Hangzhou 310023China CNPC Key Laboratory of Carbonate Reservoir Hangzhou 310023China

Based on comprehensive analysis of core,cast thin section,logging and seismic data,the sedimentary and reservoir architectures of the MB 1-2 sub-member of Mishrif Formation in Halfaya Oilfield,Iraq,are studied.The MB 1-2 sub-member of Mishrif Formation has three types of microfacies,lagoon,bioclastic shoal,and tidal channel,and facies architecture controlled by sequence stratigraphy.In the 4th-order sequence,the lagoon facies aggradated vertically,and the bioclastic shoals in lenticular shape embed in the background of lagoon,the end of the sequence is incised by the"meandering river"shape tide channel,which represents the depositional discontinuity.Three types of reservoirs including tidal channel grainstone to packstone reservoirs,bioclastic shoal grainstone to packstone reservoirs and dissolved lagoon wackestone reservoirs are developed.The reservoir architectures within tidal channel and bioclastic shoal are strickly controlled by grainy facies,whereas the dissolved lagoon reservoirs controlled by both facies and dissolution are related to the sequence boundary.The reservoir sections occur mainly in the 4 th sequence highstand systems tract(HST)and are separated by barriers formed in the transgressive systems tract(TST).Complicated facies architecture and dissolution modification resulted in strong heterogeneity within the reservoir,which showed the characteristics of"attic type"architecture.The results of this study can guide the development of similar reservoirs in the Middle East.

关键词： Iraq Halfaya Oilfield Cretaceous Mishrif Formation sedimentary microfacies reservoir architecture

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Impedance spectroscopy for quantum dot light-emitting diodes

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半导体学报:英文版 2023年第9期44卷 26-38页

作者： Xiangwei Qu xiaowei sun Institute of Nanoscience and Applications and Department of Electrical and Electronic EngineeringSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of Energy Conversion and Storage Technologies(Southern University of Science and Technology) Ministry of Educationand Shenzhen Key Laboratory for Advanced Quantum Dot Displays and LightingSouthern University of Science and TechnologyShenzhen 518055China

Impedance spectroscopy has been increasingly employed in quantum dot light-emitting diodes(QLEDs)to investigate the charge dynamics and device physics.In this review,we introduce the mathematical basics of impedance spectroscopy that applied to QLEDs.In particular,we focus on the Nyquist plot,Mott-Schottky analysis,capacitance-frequency and capacitance-voltage characteristics,and the d C/d V measurement of the QLEDs.These impedance measurements can provide critical information on electrical parameters such as equivalent circuit models,characteristic time constants,charge injection and recombination points,and trap distribution of the QLEDs.However,this paper will also discuss the disadvantages and limitations of these measurements.Fundamentally,this review provides a deeper understanding of the device physics of QLEDs through the application of impedance spectroscopy,offering valuable insights into the analysis of performance loss and degradation mechanisms of QLEDs.

关键词： quantum dot light-emitting diode impedance spectroscopy equivalent circuit model charge dynamics

Virtual simulation experiment of the design and manufacture of a beer bottle-defect detection system

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Virtual Reality & Intelligent Hardware 2020年第4期2卷 354-367页

作者： Yuxiang ZHAO xiaowei AN Nongliang sun College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

Background Machine learning-based beer bottle-defect detection is a complex technology that runs automatically;however,it consumes considerable memory,is expensive,and poses a certain danger when training novice operators.Moreover,some topics are difficult to learn from experimental lectures,such as digital image processing and computer vision.However,virtual simulation experiments have been widely used to good effect within education.A virtual simulation of the design and manufacture of a beer bottle-defect detection system will not only help the students to increase their image-processing knowledge,but also improve their ability to solve complex engineering problems and design complex systems.Methods The hardware models for the experiment(camera,light source,conveyor belt,power supply,manipulator,and computer)were built using the 3DS MAX modeling and animation software.The Unreal Engine 4(UE4)game engine was utilized to build a virtual design room,design the interactive operations,and simulate the system operation.Results The results showed that the virtual-simulation system received much better experimental feedback,which facilitated the design and manufacture of a beer bottle-defect detection system.The specialized functions of the functional modules in the detection system,including a basic experimental operation menu,power switch,image shooting,image processing,and manipulator grasping,allowed students(or virtual designers)to easily build a detection system by retrieving basic models from the model library,and creating the beer-bottle transportation,image shooting,image processing,defect detection,and defective-product removal.The virtual simulation experiment was completed with image processing as the main body.Conclusions By mainly focusing on bottle mouth defect detection,the detection system dedicates more attention to the user and the task.With more detailed tasks available,the virtual system will eventually yield much better results as a training tool for image processing education.In addition,a novel

关键词： Virtual simulation experiment Beer bottle defect detection Image processing Training tool

Single-cell analysis of transcription factor regulatory networks reveals molecular basis for subtype-specific dysregulation in acute myeloid leukemia

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Blood Science 2022年第2期4卷 65-75页

作者： Ruixia sun Lina sun xiaowei Xie Xuan Li Peng Wu Lu Wang Ping Zhu State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood DiseasesHaihe Laboratory of Cell EcosystemInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjinChina Center for Stem Cell Medicine and Department of Stem Cell&Regenerative Medicine Chinese Academy of Medical Sciences&Peking Union Medical CollegeTianjinChina

Highly heterogeneous acute myeloid leukemia(AML)exhibits dysregulated transcriptional programs.Transcription factor(TF)regulatory networks underlying AML subtypes have not been elucidated at single-cell resolution.Here,we comprehensively mapped malignancy-related TFs activated in different AML subtypes by analyzing single-cell RNA sequencing data from AMLs and healthy donors.We first identified six modules of regulatory networks which were prevalently dysregulated in all AML patients.AML subtypes featured with different malignant cellular composition possessed subtype-specific regulatory TFs associated with differentiation suppression or immune modulation.At last,we validated that ERF was crucial for the development of hematopoietic stem/progenitor cells by performing loss-and gain-of-function experiments in zebrafish embryos.Collectively,our work thoroughly documents an abnormal spectrum of transcriptional regulatory networks in AML and reveals subtype-specific dysregulation basis,which provides a prospective view to AML pathogenesis and potential targets for both diagnosis and therapy.

关键词： Acute myeloid leukaemia Co-expression analysis Single-cell RNA-sequencing Transcription factor Transcriptional regulatory network

PSLDA:a novel supervised pseudo document-based topic model for short texts

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Frontiers of Computer Science 2022年第6期16卷 71-80页

作者： Mingtao sun xiaowei ZHAO Jingjing LIN Jian JING Deqing WANG Guozhu JIA School of Economics and Management Beihang UniveristyBeijing100191China School of Computer Science Beihang UniversityBeijing100191China School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing100191China

Various kinds of online social media applications such as Twitter and Weibo,have brought a huge volume of short texts.However,mining semantic topics from short texts efficiently is still a challenging problem because of the sparseness of word-occurrence and the diversity of topics.To address the above problems,we propose a novel supervised pseudo-document-based maximum entropy discrimination latent Dirichlet allocation model(PSLDA for short).Specifically,we first assume that short texts are generated from the normal size latent pseudo documents,and the topic distributions are sampled from the pseudo documents.In this way,the model will reduce the sparseness of word-occurrence and the diversity of topics because it implicitly aggregates short texts to longer and higher-level pseudo documents.To make full use of labeled information in training data,we introduce labels into the model,and further propose a supervised topic model to learn the reasonable distribution of topics.Extensive experiments demonstrate that our proposed method achieves better performance compared with some state-of-the-art methods.

关键词： supervised topic model short text pseudo-document

Boosting selectivity and stability on Pt/BN catalysts for propane dehydrogenation via calcination & reduction-mediated strong metal-support interaction

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Journal of Energy Chemistry 2022年第4期31卷 451-457页

作者： Yaoxin Wang Jiandian Wang Ping Zheng Changyong sun Junyin Luo xiaowei Xie Key Laboratory of Clean Chemical Technology of Guangdong Regular Higher Education Institutions School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006GuangdongChina

Propane dehydrogenation(PDH) provides an alternative route for producing propylene. Herein, we demonstrates that h-BN is a promising support of Pt-based catalysts for PDH. The Pt catalysts supported on h-BN were prepared by an impregnation method using Pt(NH_(3))_(4)(NO_(3))_(2) as metal precursors. It has been found that the Pt/BN catalyst undergoing calcination and reduction is highly stable in both PDH reaction and coke-burning regeneration, together with low coke deposition and outstanding propylene selectivity(99%). Detailed characterizations reveal that the high coke resistance and high propylene selectivity of the Pt/BN catalyst are derived not only from the absence of acidity on BN support, but also from the calcination-induced and reduction-adjusted strong metal-support interaction(SMSI) between Pt and BN, which causes the partial encapsulation of Pt particles by BO_(x) overlayers. The BO_(x) overlayers can block the low-coordinated Pt sites and constrain Pt particles into smaller ensembles, suppressing side reactions such as cracking and deep dehydrogenation. Moreover, the BO_(x) overlayers can effectively inhibit Pt sintering by the spatial isolation of Pt during periodic reaction-regeneration cycles. In this work, the catalyst support for PDH is expanded to nonoxide BN, and the understanding of SMSI between Pt and BN will provide rational design strategy for BN-based catalysts.

关键词： Pt catalyst BN SMSI Propane dehydrogenation Selectivity Stability Coke Sintering

Evaluation of somatic embryo production during embryogenic tissue proliferation stage using morphology,maternal genotype,proliferation rate and tissue age of Pinus thunbergii Parl

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Journal of Forestry Research 2022年第2期33卷 445-454页

作者： Tingyu sun Yanli Wang Lihua Zhu xiaowei Liu Qingtong Wang Jianren Ye College of Forestry Nanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China Jiangsu Key Laboratory for Prevention and Management of Invasive Species Nanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China Collaborative Innovation Center of Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China

To determine the optimal embryogenic capacity(somatic embryo production)of the selected elite nematode-resistant genotypes of Pinus thunbergii,variables such as embryogenic tissue(ET)morphology,maternal genotype,proliferation rate and tissue age were analyzed.ET morphology and histological evaluation of the proliferation stage showed a decrease in filamentous clump and protuberant surfaces and a decline in the acetocarmine-staining area,which indicates a decrease in somatic embryo production(SEP).Variations in cell physiology during the prolifera-tion stage showed that SEP was positively correlated with soluble sugars and proteins,but negatively correlated with starch,peroxidase,and superoxidase.In addition,SEP was significantly(p<0.001)affected by maternal genotype,tis-sue age and proliferation rate.Moreover,SEP was positively correlated with proliferation rate(r=0.98,p<0.001),but negatively correlated with tissue age(r=−0.95,p<0.001).In general,the results suggest that SEP could be assessed in ET proliferation stages by the apparent cell morphology,histology,proliferation rate and tissue age,which provides novel insights for evaluating the ET maturation capacity(number of somatic embryos)during the proliferation stage of P.thunbergii somatic embryogenesis.

关键词： Somatic embryo production Cell physiology Cell morphology Pinus thunbergii

Research on error compensation of robot based on multi-hole measurement technology and particle swarm optimization

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The Journal of China Universities of Posts and Telecommunications 2021年第4期28卷 88-96页

作者： Wang Xianlun sun Yuxuan Wang Dong Hu xiaowei School of Electrical and Mechanical Engineering Qingdao University of Science and TechnologyQingdao 266000China

Robot error compensation is a technique for enhancing the positioning accuracy of the system. This paper presented an error measuring technique for serial robots based on the multi-hole measuring method, combined with the intelligent particle swarm optimisation(PSO) to obtain the optimal solution of the robot’s error compensation values, thereby improving the positioning accuracy of the robot. In the experiment, the robot error was measured using self-made multi-hole measuring plates and probes, and the experimental data were combined with PSO for the error comprehensive analysis. The results showed that on this type of serial robot, the multi-hole measuring method and PSO algorithm had obvious error compensation effects, which effectively improved the positioning accuracy of the robot, with the error reduced by 35% after compensation.

关键词： error model multi-hole measuring technique particle swarm optimisation error compensation

A Novel Surface Treatment Method for Improving the Antenna System Performance of Mobile Phones with Stainless Steel Frame

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Chinese Journal of Electronics 2014年第2期23卷 432-436页

作者： ZHONG Jiangwei LIU Dingxin LI Zhuo SUN Xiaowei Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Graduate University of Chinese Academy of Sciences Lenovo Research Shanghai Branch

A novel surface treatment method of plating Cu+PPS film/coating on a mobile phone’s stainless steel frame for improving the antenna system efficiencies is proposed. The mobile phone was measured in free space, in a silicon cover, and in the hand and cover simultaneously. It’s found that with this surface treatment, the total efficiency of the antenna system can be improved in all the four cases respectively by 14.22%,1.38%, 15.19% and 1.72% at 940 MHz(GSM900:880–960 MHz), 2.59%, 3.21%, 4.81% and 1.43% at 1720 MHz(DCS:1710–1880 MHz) and 6.34%, 2.85%, 9.83% and2.32% at 2100 MHz(WCDMA:1920–2170 MHz). This lowcost surface treatment method is an important breakthrough to improve antenna system performance of mobile phones especially for those with a stainless steel frame, and suitable for mass production.

关键词： Antenna efficiency Surface treatment Stainless steel Hand impacts Frequency offset Insulation layer Wave-transparent material