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Increasing the Content of β Phase of Poly(9,9-dioctylfluorene) by Synergistically Controlling Solution Aggregation and Extending Film-forming Time

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Chinese Journal of Polymer Science 2019年第7期37卷 664-673页

作者： Ya-Di Liu Qiang Zhang xin-hong yu Jian-Gang Liu Yan-Chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

For poly(9,9-dioctylfluorene)(PFO),β phase (coplanar conformation with the intra-chain torsion angle of 165°) has a greater conjugation length and higher degree of order compared to those of α phase, which favors charge carrier transport. However, the highest content of β phase obtained so far is 45%. We propose to increase the content of β phase by promoting the solution aggregation of PFO molecules and extending film-forming time. For this purpose, 1,8-diiodooctane (DIO) is added to PFO o-xylene solution, which enhances the interaction of PFO chains and improves the planarity of PFO backbone, resulting in the formation of ordered aggregation. The aggregates act as nucleation centers to promote the formation of β phase. The content of β phase increases with increasing DIO concentration and reaches a platform of 39% as DIO is more than 4 vol%. Furthermore, the film is kept in a sealed environment with oxylene atmosphere for 3 h, thus the PFO molecules have enough time to diffuse to the crystallization front and achieve disorder-order transition. As a result, the crystallinity of PFO is improved significantly and the content of β phase increases to 52%, reaching the highest value reported so far.

关键词： β Phase Ordered aggregation Film-forming time Disorder-order transition

To improve alignment of isoindigo-based conjugated polymer film by controlling contact line receding velocity

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Chinese Chemical Letters 2017年第8期28卷 1663-1669页

作者： Shuai-Jie Chi Liang Chen hong-Xiang Li Jian-Gang Liu xin-hong yu Yan-Chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of the Chinese Academy of Sciences Beijing 100049China

The macroscopic alignment of conjugated polymers with low grain boundary is essential to carrier transport. During film forming process, the match between contact line receding velocity and the critical alignment velocity is essential to get the alignment polymer film. In this paper, the contact line receding velocity of a D-A conjugated polymer film, isoindigo and bithiophene（IIDDT-C3）, was adjusted by solvent vapor content and film-formation temperature. Only when solvent vapor content was 0.3 m L and the film-formation temperature was 90C, the contact line receding velocity was in accordance with the critical alignment velocity, and the highest degree of alignment was attained in the IIDDT-C3 film, with the dichroic ratio up to 4.08. Fibers were aligned parallel with the direction of the contact line receding and the molecules of IIDDT-C3 adopted an edge-on orientation with the backbone parallel with the direction of fiber long axis. The p-p stacking distance between adjacent molecules was 3.63 ？.

关键词： IID-based conjugated polymers Alignment Contact line receding velocity Critical alignment velocity

Inflammatory myofibroblastic tumor of the central nervous system:A case report

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World Journal of Clinical Cases 2022年第34期10卷 12637-12647页

作者： Zhen-Jin Su Ze-Shang Guo Heng-Tong Wan xin-yu hong Department of Neurosurgical Oncology The First Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND An inflammatory myofibroblastic tumor(IMT)occurring in the central nervous system is very rare,and thus its pathogenesis is *** case report and literature review aimed to explore the pathogenesis,clinical features,imaging findings,pathological characteristics,immunohistochemical characteristics,diagnoses,treatments,and risks of postoperative recurrence of IMT in the central nervous *** SUMMARY A 67-year-old woman was admitted to the hospital with an exophthalmic protrusion and double vision in the left eye that had persisted for 3 *** resonance imaging(MRI)showed a 2.4 cm×1.3 cm heterogeneous large mass in the bottom of the left anterior cranial fossa,which was closely related to the dura *** surgery,we suspected the mass to be *** entire mass was successfully removed under neuronavigation and electrophysiological monitoring,and postoperative pathology indicated an IMT with extensive infiltration of chronic inflammatory cells and scattered multinucleated giant *** MRI at the 3-mo follow-up showed that the tumor at the bottom of left anterior cranial fossa had been completely resected without *** From the histological,immunohistochemical,and genetic analyses,the present case suggests that the pathogenesis of IMT-CNS is related to autoimmunity.

关键词： Inflammatory myofibroblastic tumor Central nervous system Pathogeny Diagnosis Treatment Risk of postoperative recurrence Case report

Influence of bifurcation position and length of side chains on the structure of isoindigo-based conjugated polymer thin films

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Chinese Chemical Letters 2017年第2期28卷 333-337页

作者： Shuai-Jie Chi Liang Chen Jian-Gang Liu xin-hong yu Yan-Chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the Chinese Academy of Sciences Beijing 100049 China

We chose a series of isoindigo-based conjugated polymer（ⅡDDT,ⅡDDT-C3 and ⅡDDT-C4） with different length of side chains and bifurcation positions to investigate the relationship between the degree of alignment and the length of side chains and bifurcation *** found that the dichroic ratio was increased from 2.37 to 5.23 when the side chain was longer and the bifurcation position was away from the *** π-π stacking distance was decreased from 3.67 A to 3.61 A when the bifurcation position was away from the backbone because of its smaller hindrance and the d-spacing of the（100）was increased from 20.06 A to 25.21 A when the side chain was *** the polymers were adopted an edge-on orientation with the backbone paralleled with the long axis of *** weak interaction of side-chain in ⅡDDT-C4 was beneficial for the molecules being rearranged in parallel during the contact line receding and the strong n-n interaction could accelerate the interchain assembly of the parallel molecules through π-π interaction to form aligned fibers.

关键词： Isoindigo-based conjugated polymers Alignment The length of side chains Bifurcation positions π-π interaction

Analysis of risk factors for postoperative deep vein thrombosis after craniotomy and nomogram model construction

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World Journal of Clinical Cases 2023年第31期11卷 7543-7552页

作者： Zhen-Jin Su hong-Rui Wang Li-Qin Liu Nan Li xin-yu hong Department of Neurosurgery The First Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Operating Theater The First Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Deep vein thrombosis(DVT)of the lower extremity is one of the most common postoperative complications,especially after craniocerebral *** may lead to pulmonary embolism,which has a devastating impact on patient *** study aimed to investigate the incidence and risk factors of DVT in the lower limbs following craniocerebral *** To identify independent risk factors for the development of postoperative DVT and to develop an effective risk prediction *** The demographic and clinical data of 283 patients who underwent craniocerebral surgery between December 2021 and December 2022 were retrospectively *** independent risk factors for lower extremity DVT were identified by univariate and multivariate analyses.A nomogram was created to predict the likelihood of lower extremity DVT in patients who had undergone craniocerebral *** efficacy of the prediction model was determined by receiver operating characteristic curve using the probability of lower extremity DVT for each *** Among all patients included in the analysis,47.7%developed lower extremity DVT following craniocerebral *** risk of postoperative DVT was higher in those with a longer operative time,and patients with intraoperative intermittent pneumatic compression were less likely to develop postoperative *** The incidence of lower extremity DVT following craniocerebral surgery is significant,highlighting the importance of identifying independent risk *** such as the use of intermittent pneumatic compression during surgery may prevent the formation of postoperative DVT.

关键词： Deep vein thrombosis Craniotomy surgery Risk factors Nomogram

Y型三通管内高压成形机理及补料比的影响研究

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材料工程 2013年第1期41卷 35-39,72页

作者：王鑫余心宏西北工业大学材料学院西安710072

由于Y型三通管结构不对称,内高压成形过程中左右冲头的轴向补料比对成形有较大的影响。利用数值模拟,基于Dynaform软件平台,建立了Y型三通管弹塑性模型,并利用该模型研究了镁合金Y型三通管热态内高压成形过程、塑性变形规律、失稳行为... 详细信息

由于Y型三通管结构不对称,内高压成形过程中左右冲头的轴向补料比对成形有较大的影响。利用数值模拟,基于Dynaform软件平台,建立了Y型三通管弹塑性模型,并利用该模型研究了镁合金Y型三通管热态内高压成形过程、塑性变形规律、失稳行为、各种成形缺陷以及补料比对成形的影响。结果表明:成形后零件左侧圆角过渡区壁厚最大,支管顶部壁厚最薄;随着补料比的增加,支管高度也随之增加,并在一定程度上能改善支管的壁厚减薄,但过度加大补料比会使支管顶部减薄严重。

关键词： Y型三通管内高压成形补料比失稳行为圆角过渡区

Rock physical characteristics of deep dolomite under complex geological conditions: A case study of 4th Member of Sinian Dengying Formation in the Sichuan Basin, China

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Petroleum Science 2024年第4期21卷 2370-2382页

作者： Chuang Li Shu-xin Pan hong-Bin Wang Ji-xin Deng Jian-Guo Zhao Zhi Li yu Zhang Northwest Branch of Research Institute of Petroleum Exploration & Development Department of Geophysics and Exploration College of Geophysics Chengdu University of Technology State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

The deep-ultra deep carbonate reservoir in China, commonly subjected to modification of multi-stage diagenesis, has extremely high heterogeneity. Conventional rock physics analysis cannot accurately identify the elastic responses of reservoir. Here, the rock physics properties of the dolomite from the 4th Member of the Sinian Dengying Formation are experimentally measured, and the change law of rock physics characteristics is investigated within the framework of the diagenetic processes by the analysis of the elastic and petrologic characteristics, pore structure, and sedimentary environments. The results show that the differentiated diagenesis results in different pore structure characteristics and microtexture characteristics of the rock. The microbial dolomite of the algal mound-grain beach facies is subjected to the contemporaneous microbial dolomitization and seepage-reflux dolomitization, penecontemporaneous selective dissolution, burial dolomitization, and hydrothermal dolomitization. The resultant crystalline dolomite is found with one main type of the dolomite crystal contact boundaries,and the dissolution pore is extensive development. The siliceous, muddy, and limy dolomite of the interbeach sea environment mainly experiences the weak capillary concentration dolomitization, intensive mechanical compaction-induced densification, and burial dolomitization. Such crystalline dolomite is observed with four types of contact boundaries, namely the dolomite contact, clay contact, quartz contact, and calcite contact boundaries, and porosity mostly attributed to residual primary inter-granular or crystalline pores. The samples with the same crystal boundary condition have consistent correlations between the compressional-and shear-wave velocities, and between the compressional-wave velocity and the velocity ratio. Additionally, the variation of the acoustic velocity with effective pressure and the intensity of pore-scale fluid-related dispersion are controlled by t

关键词： Deep-ultra deep carbonate reservoirs Rock physics properties Dolomite Seismic elastic properties Micro-crack Pore structure types

Poles Extraction Based LiDAR Localization for Autonomous Robot Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1413-1424页

作者： hong xin DONG Yi College of Electronic and Information Engineering Tongji UniversityShanghai 201800China

With the development of intelligent technology,the problem of Li DAR-based localization has played an increasingly important role in the localization of robots in unmanned *** the dense point clouds from the environment requires a large amount of memory,specific and stable structural features,such as pole-like objects in the environment,can serve as the ideal landmarks for localization in unmanned systems,which can effectively reduce the memory usage and mitigate the effects of dynamic environment *** this paper,the authors propose a pole-like objects extraction approach and then,it is applied into the localization system of mobile *** the same experimental conditions,the proposed method can extract more pole-like objects and achieve better long-term localization accuracy than some existing methods in different urban environmental datasets.

关键词： Pole-like landmark extraction robot localization

GPa-level pressure-induced enhanced corrosion resistance in TiZrTaNbSn biomedical high-entropy alloy

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China Foundry 2024年第3期21卷 265-275页

作者： Xiao-hong Wang yu-lei Deng Qiao-yu Li Zhi-xin Xu Teng-fei Ma xing Yang Duo Dong Dong-dong Zhu Xiao-hong Yang Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina School of Materials Science and Engineering Taizhou UniversityTaizhou 318000ZhejiangChina

TiZrTaNb-based high-entropy alloys(HEAs)are research frontier of biomedical materials due to their high hardness,good yield strength,excellent wear resistance and corrosion ***,as an essential trace element in the human body that plays a significant role in physiological *** has stable chemical properties and a low elastic *** this study,a new material,TiZrTaNbSn HEAs,was proposed as a potential biomedical *** Ti_(35)Zr_(25)Ta_(15)Nb_(15)Sn_(10)biomedical high-entropy alloys(BHEAs)were successfully prepared through an arc melting furnace and then remelted using a German high-temperature and high-pressure apparatus under GPa-level(4 GPa and 7 GPa).The precipitation behavior of the needle-like HCP-Zr_(5)Sn_(3)phase that precipitates discontinuously at the grain boundary was successfully *** phase constitution,microstructure,and corrosion resistance of the alloy were *** results show that the needle-like HCP-Zr_(5)Sn_(3)phase is eliminated and the(Zr,Sn)-rich nano-precipitated phase is precipitated in the microstructure under high pressure,which leads to the narrowing of grain boundaries and consequently improves the corrosion resistance of the *** addition,the formation mechanisms of(Zr,Sn)-rich nanoprecipitates in BHEAs were *** Zr and Sn dissolve in the matrix due to the effect of high pressure,during the cooling process,they precipitate to form a(Zr,Sn)-rich nano-precipitated phase.

关键词： biomedical HEAs precipitation grain boundary corrosion resistance TiZrTaNbSn