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Measurements of argon metastable density using the tunable diode laser absorption spectroscopy in Ar and Ar/O2

Chinese Physics B 2018年第6期27卷 298-306页

作者： Dao-Man Han Yong-Xin Liu Fei Gao Wen-Yao Liu Jun Xu you-nian wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams （Ministry of Education） School of Physics Dalian University of Technology Dalian 116024 China National Demonstration Center for Experimental Physics Education Dalian University of Technology Dalian 116024 China

Densities of Ar metastable states 1s5 and 1s3 are measured by using the tunable diode laser absorption spectroscopy（TDLAS） in Ar and Ar/O2 mixture dual-frequency capacitively coupled plasma（DF-CCP）. We investigate the effects of high-frequency（HF, 60 MHz） power, low-frequency（LF, 2 MHz） power, and working pressure on the density of Ar metastable states for three different gas components（0%, 5%, and 10% oxygen mixed in argon）. The dependence of Ar metastable state density on the oxygen content is also studied at different working pressures. It is found that densities of Ar metastable states in discharges with different gas components exhibit different behaviors as HF power increases. With the increase of HF power, the metastable density increases rapidly at the initial stage, and then tends to be saturated at a higher HF power. With a small fraction（5% or 10%） of oxygen added in argon plasma, a similar change of the Ar metastable density with HF power can be observed, but the metastable density is saturated at a higher HF power than in the pure argon discharge. In the DF-CCP, the metastable density is found to be higher than in a single frequency discharge, and has weak dependence on LF power. As working pressure increases, the metastable state density first increases and then decreases,and the pressure value, at which the density maximum occurs, decreases with oxygen content increasing. Besides, adding a small fraction of oxygen into argon plasma will significantly dwindle the metastable state density as a result of quenching loss by oxygen molecules.

关键词： argon metastable states tunable diode laser absorption spectroscopy capacitively coupled plasmas

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Effect of radio frequency bias on plasma characteristics of inductively coupled argon discharge based on fluid simulations

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Chinese Physics B 2020年第9期29卷 369-376页

作者： Xiao-Yan Sun Yu-Ru Zhang Sen Chai you-nian wang Yan-Yan Chu Jian-Xin He Textile and Garment Industry of Research Institute Zhongyuan University of TechnologyZhengzhou 450007China Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China China Special Equipment Inspection and Research Institute Beijing 100029China

t A fluid model is employed to investigate the effect of radio frequency bias on the behavior of an argon inductively coupled plasma(ICP).In particular,the effects of ICP source power,single-frequency bias power,and dual-frequency bias power on the characteristics of ICP are simulated at a fixed pressure of 30 mTorr(1 Torr=1.33322×102 Pa).When the bias frequency is fixed at 27.12 MHz,the two-dimensional(2D)plasma density profile is significantly affected by the bias power at low ICP source power(e.g.,50 W),whereas it is weakly affected by the bias power at higher ICP source power(e.g.,100 W).When dual-frequency(27.12 MHz/2.26 MHz)bias is applied and the sum of bias powers is fixed at 500 W,a pronounced increase in the maximum argon ion density is observed with the increase of the bias power ratio in the absence of ICP source *** the ratio of 27.12-MHz/2.26-MHz bias power decreases from 500 W/0 W to 0 W/500 W with the ICP source power fixed at 50 W,the plasma density profiles smoothly shifts from edge-high to center-high,and the effect of bias power on the plasma distribution becomes weaker with the bias power ratio ***,the axial ion flux at the substrate surface is characterized by a maximum at the edge of the *** the ICP source power is higher,the 2D plasma density profiles,as well as the spatiotemporal and radial distributions of ion flux at the substrate surface are characterized by a peak in the reactor center,and the distributions of plasma parameters are negligibly affected by the dual-frequency bias power ratio.

关键词： fluid simulation single-and dual-frequency bias power plasma distribution

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Fundamental study towards a better understanding of low pressure radio-frequency plasmas for industrial applications

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Chinese Physics B 2022年第8期31卷 14-36页

作者： Yong-Xin Liu Quan-Zhi Zhang Kai Zhao Yu-Ru Zhang Fei Gao Yuan-Hong Song you-nian wang Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

Two classic radio-frequency(RF) plasmas, i.e., the capacitively and the inductively coupled plasmas(CCP and ICP),are widely employed in material processing, e.g., etching and thin film deposition, etc. Since RF plasmas are usually operated in particular circumstances, e.g., low pressures(m Torr-Torr), high-frequency electric field(13.56 MHz-200 MHz),reactive feedstock gases, diverse reactor configurations, etc., a variety of physical phenomena, e.g., electron resonance heating, discharge mode transitions, striated structures, standing wave effects, etc., arise. These physical effects could significantly influence plasma-based material processing. Therefore, understanding the fundamental processes of RF plasma is not only of fundamental interest, but also of practical significance for the improvement of the performance of the plasma sources. In this article, we review the major progresses that have been achieved in the fundamental study on the RF plasmas,and the topics include 1) electron heating mechanism, 2) plasma operation mode, 3) pulse modulated plasma, and 4) electromagnetic effects. These topics cover the typical issues in RF plasma field, ranging from fundamental to application.

关键词： RF plasma electron heating discharge mode pulse modulation electromagnetic effects

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Synthesis and Thermal Stability of Antimony Tris (Thioethyl Stearate) for PVC

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Journal of Central South University 2000年第3期12卷 146-148页

作者： LIU you nian,wang Chun jiang,SHU Wan gen,ZENG Dong ming,Chen Qi yuan (College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China) College of Chemistry and Chemical Engineering Central South University Changsha China

A novel type of thermal stabilizer-antimony tris (thioethyl stearate) (ATS) was synthsized. Its thermal stability was measured by heat-aging oven test when incorporated into PVC. ATS was synthesized from stearic acid, antimony trioxide and 2-mercaptoethanol in two steps. The reaction conditions of synthesis were optimized through orthogonal test. Experimental results show that the molar ratio of stearic acid and antimony tris (2-hydroxyethylthiolate) was 1.2, adding 0.6%tetra-n-butyl titanate as catalyst and xylene as azeotropic solvent, heating and refluxing for about 4 h, and the yield of ATS is 83.9%. The thermal stability time is about 40 min(at 200 °C) when added 2phr(per hundred resin) in PVC. The thermal stability of ATS is better than that of Ca-Zn complex and basic lead stabilizers, and equal to that of dibutyltin dilaurate.

关键词： thermal stabilizer antimony thiolate synthesis thermal stability

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Mechanism of a dual-phase Ti-Nb alloy exhibiting near-linear elastic deformation

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Rare Metals 2024年第5期43卷 2282-2289页

作者： Yan Guo wang Ding Wen Ma Shun Guo Hao-Dong Meng nian-Yao Xu School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China youke Publishing Co. LtdChina Grinm Group Co.LtdBeijing 100088China

In this work,the underlying mechanism responsible for the near-linear elastic deformation behavior of a dual-phase Ti-Nb alloy consisting of β and α'' phase with large recoverable strain was systematically *** on in situ synchrotron X-ray diffraction(SXRD)analyses,it was found that besides intrinsic elastic deformation,a slight reversible β-α'' stress-induced martensitic(SIM)transformation,which proceeded in a consecutive mode under the retarding effect of micro-defects,took place during the near-linear elastic *** unloading,a small amount of residual macroscopic strain remained in the specimen due to the incomplete reverse α''→β transformation on *** high near-linear elastic deformability of the cold drawing(CD)Ti-Nb alloy has been revealed to be attributed to the coupling actions of intrinsic elasticity as well as the consecutive and reversible β-α'' SIM *** research may contribute to a new avenue for the design and development of novel dual-phase Ti-based alloys with desirable elastic deformability.

关键词： Titanium alloys Dual-phase Near-linear elastic deformation Martensitictransformation

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Optimized Auxiliary Frequency Control of Wind Farm Based on Piecewise Reduced-order Frequency Response Model

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 791-802页

作者： Xu Zhang Chen Zhao Junchao Ma Long Zhang Dan Sun Chenxu wang Yan Peng Heng nian the School of Electrical Engineering Zhejiang UniversityHangzhou 310058China Electric Power Research Institute of State Grid Zhejiang Electric Power Corporation Hangzhou 310014China

With the increasing wind power penetration in the power system,the auxiliary frequency control(AFC)of wind farm(WF)has been widely *** traditional system frequency response(SFR)model is not suitable for the wind power generation system due to its poor accuracy and *** this paper,a piecewise reduced-order frequency response(PROFR)model is proposed,and an optimized auxiliary frequency control(O-AFC)scheme of WF based on the P-ROFR model is ***,a full-order frequency response model considering the change in operating point of wind turbine is established to improve the *** order to simplify the fullorder model,a P-ROFR model with second-order structure and high accuracy at each frequency response stage is *** on the proposed P-ROFR model,the relationship between the frequency response indexes and the auxiliary frequency controller coefficients is expressed ***,an OAFC scheme with the derived explicit expression as the optimization objective is proposed in order to improve the frequency support capability on the premise of ensuring the full release of the rotor kinetic energy and the full use of the effect of time delay on frequency ***,the effectiveness of the proposed P-ROFR model and the performance of the proposed OAFC scheme are verified by simulation studies.

关键词： Frequency response piecewise reduced-order wind farm auxiliary frequency control

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RAD-seq data reveals robust phylogeny and morphological evolutionary history of Rhododendron

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Horticultural Plant Journal 2024年第3期10卷 866-878页

作者： Yuanting Shen Gang Yao Yunfei Li Xiaoling Tian Shiming Li nian wang Chengjun Zhang Fei wang Yongpeng Ma Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China Beijing Genomics of Institute ShenzhenGuangdong 518120China Guiyang Institute of Humanities and Technology GuiyangGuizhou 550025China State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River College of ForestryShandong Agricultural UniversityTai'anShandong 271018China The Southwest China of Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China West China Subalpine Botanical Garden Institute of BotanyChinese Academy of SciencesChengduSichuan 611834China

Rhododendron is famous for its high ornamental ***,the genus is taxonomically difficult and the relationships within Rhododendron remain *** addition,the origin of key morphological characters with high horticulture value need to be *** problems largely hinder utilization of germplasm *** studies attempted to disentangle the phylogeny of Rhododendron,but only used a few genomic markers and lacked large-scale sampling,resulting in low clade support and contradictory phylogenetic ***,we used restriction-site associated DNA sequencing(RAD-seq)data and morphological traits for 144 species of Rhododendron,representing all subgenera and most sections and subsections of this species-rich genus,to decipher its intricate evolutionary history and reconstruct ancestral *** results revealed high resolutions at subgenera and section levels of Rhododendron based on RAD-seq *** optimal phylogenetic tree and split tree recovered five lineages among ***(cladeⅠ)formed the basal *** and Azaleastrum formed cladeⅡand had sister ***Ⅲincluded all scaly rhododendron ***(cladeⅣ)formed a sister group to ***(cladeⅤ).The results of ancestral state reconstruction showed that Rhododendron ancestor was a deciduous woody plant with terminal inflorescence,ten stamens,leaf blade without scales and broadly funnelform corolla with pink or purple *** study shows significant distinguishability to resolve the evolutionary history of Rhododendron based on high clade support of phylogenetic tree constructed by RAD-seq *** also provides an example to resolve discordant signals in phylogenetic trees and demonstrates the application feasibility of RAD-seq with large amounts of missing data in deciphering intricate evolutionary ***,the reconstructed ancestral state of six important characters provides insights into the inn

关键词： Rhododendron RAD-seq Missing data Quartet sampling(QS) Ancestral state reconstruction

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The chlorine evolution reaction promoted by organocatalysts with amide functional groups

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Science China Chemistry 2024年第3期67卷 749-750页

作者： Lan Zhao Liang-nian He State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

Since the nineteenth century, the chlor-alkali process entails the electrochemical oxidation of sodium chloride solutions to Cl_(2) by the chlorine evolution reaction(CER) and the simultaneous production of sodium hyd... 详细信息

关键词： chlorine hydroxide promoted

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Temporal and Spatial Optimization for 5G Base Station Groups in Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1159-1169页

作者： Silu Zhang nian Liu Jianpei Han Department of Electrical and Electronic Engineering North China Electric Power UniversityBeijingChina

With the large-scale connection of 5G base stations(BSs)to the distribution networks(DNs),5G BSs are utilized as flexible loads to participate in the peak load regulation,where the BSs can be divided into base station groups(BSGs)to real-ize inter-district energy transfer.A Stackelberg game-based opti-mization framework is proposed,where the distribution net-work operator(DNO)works as a leader with dynamic pricing for multi-BSGs;while BSGs serve as followers with the ability of demand response to adjust their charging and discharging strategies in temporal dimension and load migration strategy in spatial ***,the presence and uniqueness of the Stackelberg equilibrium(SE)are ***,differ-ential evolution is adopted to reach the SE and the optimization problem in multi-BSGs is decomposed to solve the time-space ***,through simulation of a practical system,the results show that the DNO operation profit is increased via cut-ting down the peak load and the operation costs for multi-BSGs are reduced,which reaches a win-win effect.

关键词： 5G base station dynamic pricing demand response energy storage load migration Stackelberg game optimization

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Single-cell RNA-seq reveals the transcriptional program underlying tumor progression and metastasis in neuroblastoma

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Frontiers of Medicine 2024年第4期18卷 690-707页

作者： Zhe nian Dan wang Hao wang Wenxu Liu Zhenyi Ma Jie Yan Yanna Cao Jie Li Qiang Zhao Zhe Liu Department of Immunology School of Basic Medical SciencesTianjin Medical UniversityTianjin300070China Zhejiang Key Laboratory of Medical Epigenetics Department of Cell BiologySchool of Basic Medical SciencesHangzhou Normal UniversityHangzhou311121China Department of Pediatric Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin300060China Collaborative Innovation Center for Cancer Personalized Medicine Nanjing Medical UniversityNanjing211166China

Neuroblastoma(NB)is one of the most common childhood *** percent of patients present with widely disseminated clinical signs at diagnosis and exhibit poor ***,the molecular mechanisms triggering NB metastasis remain largely *** this study,we generated a transcriptomic atlas of 15447 NB cells from eight NB samples,including paired samples of primary tumors and bone marrow *** used time-resolved analysis to chart the evolutionary trajectory of NB cells from the primary tumor to the metastases in the same patient and identified a common‘starter’subpopulation that initiates tumor development and ***‘starter’population exhibited high expression levels of multiple cell cycle-related genes,indicating the important role of cell cycle upregulation in NB tumor *** addition,our evolutionary trajectory analysis demonstrated the involvement of partial epithelial-to-mesenchymal transition(p-EMT)along the metastatic route from the primary site to the bone *** study provides insights into the program driving NB metastasis and presents a signature of metastasis-initiating cells as an independent prognostic indicator and potential therapeutic target to inhibit the initiation of NB metastasis.

关键词： single-cell RNA sequencing metastasis neuroblastoma epithelial-to-mesenchymal transition

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