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Effect of Thermomechanical Parameters on Σ3~n Grain Boundaries and Grain Boundary Networks of a New Superaustenitic Stainless Steel

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Journal of Iron and Steel Research International 2014年第1期21卷 109-115页

作者： Hong-ying sun Zhang-jian ZHOU Man WANG xiao LI School of Materials Science and Engineering University of Science and Technology Beijing Technology Center Anyang Iron and Steel Group Company Metallurgy Engineering Research Institute University of Science and Technology Beijing

Hot compression tests were conducted in a temperature range of 800--1100 ℃and strain rate range of 0. 1- 10 s^-1 using a Gleeble 3500 thermomechanical simulator to investigate the influence of hot deformation parameters （temperatures, strain rates and strains） on the grain boundary network evolution of a new grade Fe-Cr-Ni superaustenitic stainless steel. The results showed that a dominant effect of deformed temperature is ∑3^n （n = 0, 1, 2, 3） boundaries population increased with decreasing temperature, while they first increased and then reduced with in- creasing strain and strain rate. Interestingly, besides E3n （n = 1, 2, 3） twin grain boundaries, some El boundaries could interrupt grain boundaries network effectively, which enhance material performances. But they are scarcely re- ported. The misorientation of some segments LAGBs in the deformed microstructure （pancaked grains） increased and slid to high angle grain boundaries with increasing the fraction of reerystallized grains during hot deformation.

关键词： superaustenitic stainless steel thermomechanieal processing electron backscatter diffraction (EBSD) coincidence site lattice grain boundary grain boundary engineering

Microstructure dependence of electrochemical corrosion resistance for rapidly solidified Ti_(50)Al_(48)Mo_(2)alloy

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Journal of Materials Science & Technology 2024年第18期185卷 58-68页

作者： Chonghao sun Ruilin xiao Kelun Liu ying Ruan Bingbo Wei MOE Key Laboratory of Materials Physics and Chemistry under Extraordinary Conditions School of Physical Science and TechnologyNorthwestern

The rapid solidification of undercooled liquid Ti_(50)Al_(48)Mo_(2)alloy was achieved by the electromagnetic lev-itation(EML)*** small and medium undercoolings,primary(βTi)dendrite reacted with sur-rounding liquid to drive a peritectic transformation into the(αTi)*** solutal Mo and Al segrega-tions were located within the dendrite center and the grain boundary during peritectic transformation,consequently B2 phase in the dendrite center andγphase at the grain boundary *** under-cooling exceeded 253 K,the peritectic transformation was completely inhibited,and the formation of the B2 phase andγphase was completely *** ultrafine eutectoid structure was formed and a complete solute trapping effect was *** solute distribution facilitated the forma-tion of thicker passivation film with lower defect density and higher film resistance on the alloy ***,this weakened micro-galvanic effect reduced the susceptibility to pitting corrosion,and conse-quently the corrosion resistance of the alloy was improved.

关键词： Ti-Al based alloys Electromagnetic levitation technique Undercooling Rapid solidification Passivation film

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

LIFTING FORCE ACTING ON A GATE WITH HIGH HEAD

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Journal of Hydrodynamics 2011年第3期23卷 379-383页

作者： LIU xiao-qing ZHAO Lan-hao CAO Hui-ying sun xiao-peng College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The hydrodynamic lifting force acting on a gate with high head is one of the key factors concerning the safety and reliability of gates. The lifting force is closely related to hydrodynamic pressure, and generally, is obtained through the model test. This work presents a method of numerical simulation based on the VOF method for the flow and FEM for the structure of a gate to investigate this kind of the lifting force. The physical model experiments were conducted about the hydrodynamic pressure and the lifting force to verify the numerical results. The comparisons of those two methods show that the maximum relative error is smaller than 11.40 % and the method presented in this paper is feasible and could be used in the designs of hydropower projects.

关键词： gate pressure high head lifting force numerical simulation physical model experiment

Preoperative prediction of malignant potential of 2-5 cm gastric gastrointestinal stromal tumors by computerized tomography-based radiomics

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World Journal of Gastrointestinal Oncology 2022年第5期14卷 1014-1026页

作者： Xue-Feng sun Hai-Tao Zhu Wan-ying Ji xiao-Yan Zhang xiao-Ting Li Lei Tang ying-Shi sun Key laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of RadiologyPeking University Cancer Hospital&InstituteBeijing 100142China

BACKGROUND The use of endoscopic surgery for treating gastrointestinal stromal tumors(GISTs)between 2 and 5 cm remains controversial considering the potential risk of metastasis and ***,surgeons are facing great difficulties and challenges in assessing the malignant potential of 2-5 cm gastric *** To develop and evaluate computerized tomography(CT)-based radiomics for predicting the malignant potential of primary 2-5 cm gastric *** A total of 103 patients with pathologically confirmed gastric GISTs between 2 and 5 cm were *** malignant potential was categorized into low grade and high grade according to postoperative pathology *** CT images were reviewed by two radiologists.A radiological model was constructed by CT findings and clinical characteristics using logistic *** features were extracted from preoperative contrast-enhanced CT images in the arterial *** XGboost method was used to construct a radiomics model for the prediction of malignant *** was established by combing the radiomics score with CT *** of the models were developed in a training group(n=69)and evaluated in a test group(n=34).RESULTS The area under the curve(AUC)value of the radiological,radiomics,and nomogram models was 0.753(95%confidence interval[CI]:0.597-0.909),0.919(95%CI:0.828-1.000),and 0.916(95%CI:0.801-1.000)in the training group vs 0.642(95%CI:0.379-0.870),0.881(95%CI:0.772-0.990),and 0.894(95%CI:0.773-1.000)in the test group,*** AUC of the nomogram model was significantly larger than that of the radiological model in both the training group(Z=2.795,P=0.0052)and test group(Z=2.785,P=0.0054).The decision curve of analysis showed that the nomogram model produced increased benefit across the entire risk threshold *** Radiomics may be an effective tool to predict the malignant potential of 2-5 cm gastric GISTs and assist preoperative clinical decision making.

关键词： Gastrointestinal stromal tumors Gastric gastrointestinal stromal tumors Computed tomography Malignant potential Radiomics Nomogram

Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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Nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin Jiang Hui-Na Liu Yu-Fan Yang Zhi-Cheng Zhang Qi Dai xiao-Yan Bao Lin-Jie Wu Ya-Xin Qin Xin Tan xiao-Yan sun Xu-Fang ying Zhi-Qing Ben Min Han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China Hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering RNA(siRNA)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRNA to overcome the problem of siRNA release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRNA,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering RNA(siRNA) doxorubicin

PLS-CCA Heterogeneous Features Fusion-based Low-resolution Human Detection Method for Outdoor Video Surveillance

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International Journal of Automation and computing 2017年第2期14卷 136-146页

作者： Hong-Kai Chen xiao-Guang Zhao Shi-ying sun Min Tan State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China

In this paper, we focus on low-resolution human detection and propose a partial least squares-canonical correlation analysis （PLS-CCA） for outdoor video surveillance. The analysis relies on heterogeneous features fusion-based human detection method. The proposed method can not only explore the relation between two individual heterogeneous features as much as possible, but also can robustly describe the visual appearance of humans with complementary information. Compared with some other methods, the experimental results show that the proposed method is effective and has a high accuracy, precision, recall rate and area under curve （AUC） value at the same time, and offers a discriminative and stable recognition performance.

关键词： Low-resolution human detection partial least squares canonical correlation analysis heterogeneous features outdoorvideo surveillance.

Feasibility of differentiating T3 from T4a gastric cancer in different Lauren classification by determining serosa invasion：Diagnostic performance of high enhanced serosa sign

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Chinese Journal of Cancer Research 2018年第2期30卷 263-271页

作者： Rui-Jia sun Lei Tang ying Chen xiao-Ting Li Yu sun Zi-Yu Li ying-Shi sun Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Department of Radiology Beijing 100142 China Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Departrnent of Pathology Beijing 100142 China Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Center of Gastrointestinal Surgery Peking University Cancer Hospital & Institute Beijing 100142 China

Objective： To study the value of high enhanced serosa sign on contrast-enhanced computed tomography（CT）in differentiating T3 from T4a gastric cancer in different Lauren ***： This study included 276 consecutive patients with surgically confirmed p T3 or p T4a gastric *** pre-operative CT images were reviewed by two radiologists blinded. The demonstration of the high enhanced serosa on CT between T3 and T4a was compared with chi-square test. The diagnostic performance of this sign on CT in the differentiation of T4a from T3 in different Lauren classification was ***： The accuracy, sensitivity, specificity, positive predictive value（PPV） and negative predictive value（NPV） for the judgement of serosa invasion using the high enhanced serosa sign on CT was 74.6%, 63.7%, 83.6%,76.0% and 73.8% by one radiologist and 76.4%, 66.1%, 84.9%, 78.1% and 75.4% by the other *** to the intestinal-type, the sensitivity of the judgement of serosa invasion using the high enhanced serosa sign on CT in diffuse-type was significant higher（80% in both readers）, while the specificity trended to be lower（65.9% and 80.5%, respectively）. There is no significant difference in the accuracy of diagnosis between intestinaltype and diffuse-type of gastric cancers（the P-values of two radiologists were 0.968, 0.591, respectively）. The combination of the high enhanced serosa sign with conventional CT signs is significant different in diagnosis of T3 and T4a（P〈0.001）. The diagnostic accuracy was increased in both radiologists after the combination. The two readers achieved substantial agreement, with Kappa coefficient of 0.63, P〈***： The high enhanced serosa sign on CT is associated with serosa involvement. The sensitivity of the judgement of serosa invasion using this sign on CT in diffuse-type was significant higher than that in intestinal-type.

关键词： Computed tomography gastric cancer staging serosa invasion imaging

Near-field time-frequency localization method using sparse representation

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 29-34页

作者： WANG Bo LIU Juan-juan sun xiao-ying ZHANG Yan-jun College of Communication Engineering Jilin University

This paper presents a novel near-field source localization method based on the time-frequency sparse model. Firstly, the method converts the time domain data of array output into time-frequency domain by time-frequency transform; then constructs sparse localization model by utilizing the specially selected time-frequency points, and finally the greedy algorithms are chosen to solve the sparse problem to localize the source. When the coherent sources exist, we propose an additional iterative selection procedure to improve the estimation performance. The proposed method is suitable for uncorrelated and coherent sources, moreover, the improved estimation accuracy and the robustness to low signal to noise ratio （SNR） are achieved. Simulations results verify the efficiency of the proposed algorithm

关键词： near-field source time-fi'equency distribution sparse representation DOA estimation range estimation greedy algorithm