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Ionization and Fragmentation of Butanone Clusters Irradiated by Photons at 355 and 118 nm

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Chemical Research in Chinese Universities 2011年第3期27卷 508-511页

作者： SUN Chang-kai HU Zhan YANG Xue JIN Ming-xing HU Wen-cheng ding da-jun Institute of Atomic and Molecular Physics Jilin University Changchun 130012 P. R. China

Time-of-flight（TOF） mass spectra of molecular butanone clusters were measured under the irradiation of photons at 355 and 118 nm. Butanone molecular parent ion and several series of butanone cluster fragments such as （CH3COC2H5）nH＋, （CH3COC2H5）nC2H5＋, （CH3COC2H5）nCH3CO＋ and （CH3COC2H5）nC2H5CO＋ were observed. Odd-even variation pattern in the intensity of （CH3COC2H5）nCH3CO＋ is obvious from n=4 to 8. A connection is es-tablished between the fragment clusters （CH3COC2H5）nCH3CO＋ and the neutral clusters （CH3COC2H5）n＋1 based on the consideration of butanone cluster dissociation mainly by losing a radical C2H5？. The stability variation of the neutral clusters calculated via the HF-B3LYP method based on DFT is in agreement with the observed phenomena experimentally, indicating （CH3COC2H5）n＋1（n＋1=5,7） with a ring structure are with higher stability over the adjacent even-number clusters.

关键词： Cluster Ionization Fragment Butanone

Optimization of resource allocation in FDD massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 117-125页

作者： jun Cai Chuan Yin Youwei ding School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing 210046China School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The performance of massive MIMO systems relies heavily on the availability of Channel State Information at the Transmitter(CSIT).A large amount of work has been devoted to reducing the CSIT acquisition overhead at the pilot training and/or CsI feedback *** fact,the downlink communication generally includes three stages,i.e.,pilot training,CsI feedback,and data *** three stages are mutually related and jointly determine the overall system ***,there exist few studies on the reduction of csIT acquisition overhead from the global point of *** this paper,we integrate the Minimum Mean Square Error(MMSE)channel estimation,Random Vector Quantization(RVQ)based limited feedback and Maximal Ratio Combining(MRC)precoding into a unified framework for investigating the resource allocation *** particular,we first approximate the covariance matrix of the quantization error with a simple expression and derive an analytical expression of the received Signal-to-Noise Ratio(SNR)based on the deterministic equivalence *** the three performance metrics(the spectral efficiency,energy efficiency,and total energy consumption)oriented problems are formulated *** practical system requirements,these three metrics can be collaboratively ***,we propose an optimization solver to derive the optimal partition of channel coherence *** results verify the benefits of the proposed resource allocation schemes under three different scenarios and illustrate the tradeoff of resource allocation between three stages.

关键词： Massive MIMO FDD CSIT Resource allocation

Ultrafast Photodissociation Dynamics of the F State of Sulfur Dioxide by Femtosecond Time-Resolved Pump-Probe Method

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Chinese Physics Letters 2011年第3期28卷 58-61页

作者： ZHANG Dong-Doug NI Qiang LUO Si-Zuo ZHANG Jing LIU Hang XU Hai-Feng JIN Ming-Xing ding da-jun Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012

A femtosecond pump-probe method is employed to study the dissociation dynamics of sulfur ***_(2)molecules are excited to the F state by absorbing two photons of 267nm femtosecond laser pulses,and ionized by 400nm laser pulses at different delay times between the two *** of both parent ions(SO_(2)^(+))and the fragment ions(SO^(+),S^(+)and O^(+)are *** S0_(2)^(+)transient can be well fitted to a biexponential decay comprising a fast and a slow component of 280fs and 2.97ps lifetimes,*** SO^(+)transient consists of two growth components of 270 fs and 2.50 *** results clearly show that the F state of S0_(2)dissociates along an S-0 *** transients of S^(+)and O^(+),however,have different behavior,which consist of a fast growth and a long decay component.A possible mechanism of the fragment formation is discussed to understand the dissociation dynamics of the F state of SO_(2).

关键词： Femto pump dissociation

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我国拱桥建设屡创辉煌

桥梁建设 2000年第1期30卷 63-68页

作者：丁大钧东南大学土木工程学院江苏南京210096

简述近些年来我国在石拱桥和混凝土拱桥建设方面取得的巨大成就 ,创造了一个接一个的世界纪录。

关键词：拱桥石桥钢筋混凝土桥组合拱桥中国

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氦原子双电子激发态的辐射光谱

原子与分子物理学报 2007年第2期24卷 411-414页

作者：丁大军吉林大学原子与分子物理研究所长春130012

利用同步辐射高等光源激发氮原子测量了在能量范围63-66eV的双电子激发态的真空紫外辐射光谱，给定了sp，2n（n至26），sp，2n-（n至24）和2pnd（n至9）的氮原子双电子激发态能级位置，获得了一些对认识原子双电子激发态过程中辐射跃迁... 详细信息

利用同步辐射高等光源激发氮原子测量了在能量范围63-66eV的双电子激发态的真空紫外辐射光谱，给定了sp，2n（n至26），sp，2n-（n至24）和2pnd（n至9）的氮原子双电子激发态能级位置，获得了一些对认识原子双电子激发态过程中辐射跃迁的影响有价值的结果．

关键词：氮原子双电子激发自电离电子关联同步辐射

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用混凝土砌块砌筑墙梁的组合作用

四川建筑科学研究 2005年第6期31卷 1-2页

作者：丁大钧东南大学江苏南京210096

对墙梁中托梁与墙中的“组合作用”进行了论述,并对国家现行规范中的计算方法提出探讨和建议,同时介绍了配筋混凝土空心砌块砌筑墙梁的初步试验结果。

关键词：托梁墙梁组合作用受弯偏心受拉空心砌块

Magnetic Interactions with Strain Gradient in Ultrathin Pr_(0.67)Sr_(0.33)MnO_(3) Films

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Engineering 2024年第9期40卷 158-165页

作者： Bangmin Zhang Ping Yang jun ding Jingsheng Chen Gan Moog Chow Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Singapore Synchrotron Light Source National University of SingaporeSingapore 117603Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Strain gradient is a normal phenomenon around a heterostructural interface in ultrathin film,and it is important to determine its effect on magnetic interactions to understand interfacial *** this work,ultrathin Pr_(0.67)Sr_(0.33)MnO_(3)(PSMO)films on different substrates are *** PSMO film under different in-plane strain conditions,the saturated magnetization and Curie temperature can be qualitatively explained by double-exchange interaction and the Jahn-Teller ***,the difference in the saturated magnetization with zero field cooling and 5 T field cooling is proportional to the strain ***-gradient-induced structural disorder is proposed to enhance phonon-electron antiferromagnetic interactions and the corresponding antiferromagnetic-to-ferromagnetic phase transition via a strong magnetic field during the field cooling process.A non-monotonous structural transition of the MnO_(6) octahedral rotation can enlarge the strain gradient in PSMO film on a SrTiO_(3) *** work demonstrates the existence of the flexomagnetic effect in ultrathin manganite film,which should be applicable to other complex oxide systems.

关键词： Strain gradient Manganite film Octahedral rotation Flexomagnetic Magnetic interactions Phase transition

Designing ultrastrong and thermally stable FeCrAl alloys with the fine-grained structure

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Journal of Materials Science & Technology 2024年第4期171卷 198-208页

作者： Shuaiyang Liu Jinyu Zhang Hui Wang Gang Liu Xiangdong ding jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Designing microstructurally stable FeCrAl alloys with excellent strength-ductility synergy is highly desir-able for their engineering ***,due to the preference nucleation of precipitates at grain boundaries(GBs),the improved precipitation strengthening of these alloys is usually accompanied by in-tergranular ***,we propose a novel thermomechanical processing route coupled with the Si alloying strategy via precipitation of coherent deformable Laves precipitates inside equiaxed fine-grains to achieve FeCrAl alloys with ultrahigh yield strength over∼992 MPa,excellent uniform elongation of∼7.6%at room temperature,and superior thermal stability at temperature∼1200℃.The Si alloying not only decreases the stacking fault energy of Laves precipitates favorable for their stacking-fault-mediated deformation but also hinders grain coarsening at 1200℃due to the Si-enrichment favorable for GB pin-ning *** results prove the possibility of achieving the collaborative enhancement of mutually exclusive properties in alloys,such as strength-ductility-thermal stability via nanoprecipitation engineer-ing,and offer a promising route to prepare dispersion-strengthened materials.

关键词： FeCrAl alloys Si alloying Mechanical properties Thermal stability Laves phase

DBT-PDP:Provable data possession with outsourced data batch transfer based on blockchain

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High-Confidence Computing

High-Confidence Computing 2024年第2期4卷 62-72页

作者： Chengming Yi Hua Zhang Weiming Sun jun ding State key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Zhe Jiang Computer Network Emergency Response Technical Team Hangzhou 310052China

In the scenario of large-scale data ownership transactions,existing data integrity auditing schemes are faced with security risks from malicious third-party auditors and are inefficient in both calculation and communication,which greatly affects their *** paper proposes a data integrity audit scheme based on blockchain where data ownership can be traded in batches.A data tag structure which supports data ownership batch transaction is adopted in our *** update process of data tag does not involve the unique information of each data,so that any user can complete ownership transactions of multiple data in a single transaction through a single transaction auxiliary *** the same time,smart contract is introduced into our scheme to perform data integrity audit belongs to third-party auditors,therefore our scheme can free from potential security risks of malicious third-party *** analysis shows that our scheme is proved to be safe under the stochastic prediction model and k-CEIDH *** with similar schemes,the experiment shows that communication overhead and computing time of data ownership transaction in our scheme is ***,the communication overhead and computing time of our scheme is similar to that of similar schemes in data integrity audit.

关键词： data integrity Cloud outsourcing audit data ownership batch transaction Blockchain Smart contract