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Three-stage alloying of[Ag_(44)(p-MBA)_(30)]^(4−)cluster with[Au_(2)(p-NTP)_(2)Cl]^(−)

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Nano Research 2022年第8期15卷 7742-7751页

作者： Baoyu Huang Xiaomei zhao yong Pei Department of Chemistry Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of EducationKey Laboratory for Green Organic Synthesis and Application of Hunan ProvinceXiangtan UniversityXiangtan 411105China

Precise control of alloying sites has long been a challenge,yet little has been achieved in the atomic-level manipulation of metallic *** study reported a three-stage metal and motif exchange mechanism of alloying reaction of an atomically precise ligand-protected[Ag_(44)(p-MBA)_(30)]^(4−)(p-MBA=para-mercaptobenzoic acid)cluster with[Au_(2)(p-NTP)_(2)Cl]^(−)(p-MBA=para-mercaptobenzoic acid).During the first stage(Stage I),an exchange of ligand-shell metal atoms took *** the second stage(Stage II),the motif exchanged on the[AuAg_(43)(p-MBA)_(30)]^(4−)*** the third stage(Stage III),the Au(I)atom in the ligand-shell was swapped with a Ag(0)atom of the icosahedral *** density functional theory(DFT)calculation results demonstrated that the metal exchange proceeded via different mechanisms at the different reaction *** reaction Stages I and II,the metal exchange proceeded via formation of a dianionic[Ag_(44)(p-MBA)_(30)]^(4−)-[Au_(2)(p-NTP)_(2)Cl]^(−)intermediate and then broke and recombined with the *** Stage III,the diffusion of the Au(I)to icosahedral Ag12-core(Stage III)was proceeded via a motif catalyzed heterometal atom diffusion *** hope that this work will provide a new perspective for the precise control of alloy position in alloyed nanomaterials.

关键词： metal cluster alloying mechanism density functional theory(DFT)calculations metal exchange

Fractionation of Polyolefin Elastomer by a Modified SSA Technique

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Chinese Journal of Polymer Science 2022年第10期40卷 1252-1258,I0010页

作者： Xin-Tong zhao yong-Feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Schoolof Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

As an important part of semicrystalline polymer materials,polyolefin elastomers are widely used,and the in-depth analysis of their molecular chain structure information is of great significance to promote their rapid *** show in this work an effort in characterizing a commercial polyolefin elastomer of ethylene/1-octene copolymer by a modified successive self-nucleation and annealing(SSA)technique.A small amount of linear polyethylene was blended with the ethylene/1-octene copolymer serving as nucleation agent during *** turned out that a tiny fraction of linear polyethylene can significantly promote the crystallization of the copolymer during cooling from different annealing temperatures and increase the melting temperature of the fractions so that providing apparent methylene sequence length much closer to the real value than obtained by traditional SSA technique.

关键词： Polyolefin elastomer Ethylene-co-octene Thermal fractionation SSA Micro structure

Variable scale-convex-peak method for weak signal detection

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Science China(Technological Sciences) 2021年第2期64卷 331-340页

作者： TIAN RuiLan zhao ZhiJie XU yong State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Applied Mathematics Northwestern Polytechnical UniversityXi’an 710072China

Avariable scale-convex-peak method is constructed to identify the frequency of weak harmonic signal. The key of this method is to find a set of optimal identification coefficients to make the transition of dynamic behavior topologically persistent. By the stochastic Melnikov method, the lower bound of the chaotic threshold continuous function is obtained in the mean-square *** intermediate value theorem is applied to detect the optimal identification coefficients. For the designated identification system, there is a valuable co-frequency-convex-peak in bifurcation diagram, which indicates the state transition of chaosperiod-chaos. With the change of the weak signal amplitude and external noise intensity in a certain range, the convex peak phenomenon is still maintained, which leads to the identification of frequency. Furthermore, the proposition of the existence of reversible scaling transformation is introduced to detect the frequency of the harmonic signal in engineering. The feasibility of constructing the hardware and software platforms of the variable scale-convex-peak method is verified by the experimental results of circuit design and the results of early fault diagnosis of actual bearings, respectively.

关键词： variable-scale Duffing system stochastic Melnikov method scale transformation circuit experiment fault diagnosis

Relative phase-dependent two-electron emission dynamics with two-color circularly polarized laser fields

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Chinese Physics B 2020年第9期29卷 281-287页

作者： Tong-Tong Xu lian-lian Zhang zhao Jin Wei-Jiang Gong College of Sciences Northeastern UniversityShenyang 110819China

With the semiclassical ensemble model, we explore the relative phase-dependent nonsequential double ionization (NSDI) of Mg by counter-rotating two-color circularly polarized (TCCP) laser pulses. The yield of Mg2+ sensitively depends on the relative phase Δφ and the intensity of TCCP laser fields. At Δφ=1.5π, the yield of Mg2+ exhibits a pronounced peak in the 0.05 PW/cm2 laser field. This behavior results from the increase of the initial transverse velocity compensating for the drift velocity with the decreasing angle by analyzing the angular distributions of the electron pairs in four relative phases. By changing the relative phases, we find that the recollision excitation with subsequent ionization and the recollision-impact ionization mechanisms can be controlled with TCCP laser fields.

关键词： nonsequential double ionization relative phases two-electron emission dynamics

The sulfolane-based liquid electrolyte with LiClO_(4)additive for the wide-temperature operating high nickel ternary cathode

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Nano Research 2023年第3期16卷 3855-3863页

作者： Yixin Zhu Shuang He Jiayi Ding Guangyu zhao Fang lian School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China University of New South Wales PontypriddCF371DLUK

An adequate wide temperature electrolyte for high nickel ternary cathode is urgent to further develop high energy density ***,a comprehensive double-salt local high-concentration sulfolane-based electrolyte(DLi)is proposed with specific sheath structure to build stable interface on the LiNi_(0.8)Co_(0.1)Mn_(0.1O2)(NCM811)cathode at wide operating temperature between−60 and 55℃.Lithium perchlorate(LiClO_(4))in combination with high concentration lithium bis-(trifluoromethanesulfonyl)imide(LiTFSI)strengthens the internal interaction between anion and cation in the solvation structure,increasing Li+transference number of the electrolyte to ***,the structure and component characteristics of the passive interface layer on NCM811 are modulated,decreasing desolvation energy of Li+ions,benefiting Li+transport dynamics especially at low temperature,and also ensuring the interfacial stability at a wide operating temperature *** a result,the cathode with DLi exhibits excellent high-temperature storage performance and high capacity retention of 80.5%in 100 cycles at 55℃.Meanwhile,the Li||NCM811 cells can deliver high discharge capacity of 160.1,136.1,and 110.3 mAh·g^(−1)under current density of 0.1 C at−20,−40,and−60℃,maintaining 84.5%,71.8%,and 58.2%of the discharge capacity at 30℃,***,it enables NCM811 cathode to achieve a reversible capacity of 142.8 mAh·g^(−1)in 200 cycles at−20℃and 0.2 *** studies shed light on the molecular strategy of wide operational temperature electrolyte for high nickel ternary cathode.

关键词： liquid electrolyte high nickel ternary cathode wide temperature interface sheath structure

Adaptive beamforming and phase bias compensation for GNSS receiver

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Journal of Systems Engineering and Electronics 2015年第1期26卷 10-18页

作者： Hongwei zhao Baowang lian Juan Feng School of Electronics and Information Northwestern Polytechnical University Shaanxi Fiber Home Communication Group Co. Ltd

Adaptive antenna arrays have been used to mitigate the interference on global navigation satellite system（GNSS） receivers. The performance of interference mitigation depends on the beamforming algorithms adopted by the antenna array. However,the adaptive beamforming will change the array pattern in realtime, which has the potential to introduce phase center biases into the antenna array. For precise applications, these phase biases must be mitigated or compensated because they will bring errors in code phase and carrier phase measurements. A novel adaptive beamforming algorithm is proposed firstly, then the phase bias induced by the proposed algorithm is estimated, and finally a compensation strategy is addressed. Simulations demonstrate that the proposed beamforming algorithm suppresses effectively the strong interference and improves significantly the capturing performance of GNSS signals. Simultaneously, the bias compensation method avoids the loss of the carrier phase lock and reduces the phase measurement errors for GNSS receivers.

关键词： global navigation satellite system(GNSS) space-time adaptive processing(STAP) adaptive beamforming bias compensation

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风筛组合式花生秧粉碎除膜机设计与试验

农机化研究 2025年第2期47卷 159-164页

作者：刘勇郑孟坤赵福勇王家胜青岛农业大学机电工程学院山东青岛266109 日照市勇杰农业装备有限公司山东日照263318

针对覆膜种植的花生收获后的地膜残留于饲料用花生秧严重影响牲畜健康的问题,结合粉碎后的花生秧与地膜的物理特性,设计了一种花生秧粉碎除膜机,可一次完成喂料粉碎、筛分输送、负压除膜、回料输送、出料收集等功能。对整机的关键部件... 详细信息

针对覆膜种植的花生收获后的地膜残留于饲料用花生秧严重影响牲畜健康的问题,结合粉碎后的花生秧与地膜的物理特性,设计了一种花生秧粉碎除膜机,可一次完成喂料粉碎、筛分输送、负压除膜、回料输送、出料收集等功能。对整机的关键部件进行了设计与分析,重点确定了粉碎装置、风筛式清选装置等部件的结构与工作参数。利用Design-Expert进行了试验设计,研究了振动筛频率、风机转速对花生秧残膜清选质量的影响,并对花生秧粉碎除膜机的工作参数进行了优化。试验结果表明:振动筛频率、风机转速对除膜率和损失率影响显著;当最优参数振动筛频率3.4 Hz、1号风机转速1000 r/min、2号风机转速1350 r/min、3号风机转速1500 r/min时,花生秧粉碎除膜机除膜率为96.8%,损失率为11.2%,实现花生秧中残膜的清选。

关键词：花生秧除膜风筛式

Thermal comfort models and their developments:A review

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Energy and Built Environment 2021年第1期2卷 21-33页

作者： Qiantao zhao Zhiwei lian Dayi Lai Department of Architecture School of DesignShanghai Jiao Tong UniversityChina

In the past several years,thermal comfort,especially development and application of thermal comfort model,has been a research focus of building *** the 1970s,a series of thermal comfort models based on people’s thermal sensation to environment have been established,and gradually became an important part of the field of thermal comfort *** this review,the existing thermal comfort models are summarized from various perspectives,such as models applied in different environments like sleeping environment and outdoor ***,models used for different groups people,such as elderly and different races are *** the part,adaptive models are *** additions,data-driven models were *** paper introduced the advantages and disadvantages of each *** on the above review,future research work of thermal comfort model is proposed.

关键词： Thermal comfort Model Human thermoregulation Built environment Development

Cross-immune tolerance:conception and its potential significance on transplantation tolerance

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Cellular & Molecular Immunology 2010年第1期7卷 20-25页

作者： yong zhao Xianchang Li Transplantation Biology Research Division State Key Laboratory of Biomembrane and Membrane BiotechnologyInstitute of ZoologyChinese Academy of SciencesBeijingChina Harvard Medical School Transplant Research CenterBeth Israel Deaconess Medical CenterBostonMAUSA

The diversity of alloreactive T cells in graft rejection and the presence of extensive crossreactivity among alloreactive T cells indicate thatthe induction oftransplantation tolerancemay fundamentally alter the size ofhost T-cell repertoireinvolved in protective immunity and immune surveillance,especially those that are crossreactive to conventional *** herein highlight the crossreactive nature of alloreactive T cells and the potential risks of altered T-cell repertoire associated with the induction of transplantation *** possibility that T-cell tolerance to one set of antigens results in their tolerance to other unrelated antigens due to T-cell crossreactivity and/or heterogeneity is defined as‘cross-immune tolerance’.The definition and significance of this concept were discussed in details.

关键词： crossreactivity T-cell repertoire tolerance transplantation