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Effect of crystallization temperature and propylene sequence length on the crystalline structure of propylene-ethylene random copolymers

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Chinese Science Bulletin 2008年第12期53卷 1804-1812页

作者： GOU QingQiang LI HuiHui YU ZhenQiang chen erqiang ZHANG YuDong YAN ShouKe Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Department of Polymer Science School of Chemistry Peking University Beijing 100871 China Beijing Research Institute of Chemical Industry SINOPEC Beijing 100013 China candidate of Graduate University of Chinese Academy of Sciences Beijing100039 China

Crystallization behavior and resultant crystalline structure of a series of temperature-rising elu-tion-fractionated specimen of a Ziegler-Natta catalyst-synthesized propylene-ethylene random co-polymer were studied by DSC, WAXD and AFM. The experimental results indicate that both crystalliza-tion temperature and propylene sequence length exhibit great influence on the crystallization behavior and crystalline structure of the copolymer. It was found that the ethylene co-monomers acting as point defects inserted into the polypropylene chains play an important role in the formation of γ-iPP. As the co-monomer content increases, the crystallizable sequence length of iPP decreases, which produces an appropriate condition for its γ crystallization. At the same time, the existence of chain defects leads to a lower crystallinity of the copolymer and imperfection of the resultant crystals. For each individual sample with certain propylene sequence length or ethylene content, the increment of γ-iPP crystal content with increasing crystallization temperature demonstrates that higher crystallization tempera-ture is in favor of the γ-iPP crystallization. Pure γ-iPP crystals have been got in samples with propylene sequence length lower than 21 under suitable crystallization conditions.

关键词：结晶温度晶体乙烯共聚物

CrossLinkNet: An Explainable and Trustworthy AI Framework for Whole-Slide Images Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4703-4724页

作者： Peng Xiao Qi Zhong Jingxue chen Dongyuan Wu Zhen Qin erqiang Zhou Network and Data Security Key Laboratory of Sichuan Province University of Electronic Science and Technology of ChinaChengdu610054China Faculty of Data Science City University of MacaoMacao999078China

In the intelligent medical diagnosis area,Artificial Intelligence(AI)’s trustworthiness,reliability,and interpretability are critical,especially in cancer *** neural networks,while excellent at processing natural images,often lack interpretability and adaptability when processing high-resolution digital pathological *** limitation is particularly evident in pathological diagnosis,which is the gold standard of cancer diagnosis and relies on a pathologist’s careful examination and analysis of digital pathological slides to identify the features and progression of the ***,the integration of interpretable AI into smart medical diagnosis is not only an inevitable technological trend but also a key to improving diagnostic accuracy and *** this paper,we introduce an innovative Multi-Scale Multi-Branch Feature Encoder(MSBE)and present the design of the CrossLinkNet *** MSBE enhances the network’s capability for feature extraction by allowing the adjustment of hyperparameters to configure the number of branches and *** CrossLinkNet Framework,serving as a versatile image segmentation network architecture,employs cross-layer encoder-decoder connections for multi-level feature fusion,thereby enhancing feature integration and segmentation *** quantitative and qualitative experiments on two datasets demonstrate that CrossLinkNet,equipped with the MSBE encoder,not only achieves accurate segmentation results but is also adaptable to various tumor segmentation tasks and scenarios by replacing different feature ***,CrossLinkNet emphasizes the interpretability of the AI model,a crucial aspect for medical professionals,providing an in-depth understanding of the model’s decisions and thereby enhancing trust and reliability in AI-assisted diagnostics.

关键词： Explainable AI security trustworthy CrossLinkNet whole slide images

A Linked List Encryption Scheme for Image Steganography without Embedding

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 331-352页

作者： Pengbiao Zhao Qi Zhong Jingxue chen Xiaopei Wang Zhen Qin erqiang Zhou Network and Data Security Key Laboratory of Sichuan Province University of Electronic Science and Technology of ChinaChengdu610054China Faculty of Data Science City University of MacaoMacao999078China Department of Computer Science and Engineering University of CaliforniaRiversideCA 92521USA

Information steganography has received more and more attention from scholars nowadays,especially in the area of image steganography,which uses image content to transmit information and makes the existence of secret information *** enhance concealment and security,the Steganography without Embedding(SWE)method has proven effective in avoiding image distortion resulting from cover *** this paper,a novel encrypted communication scheme for image SWE is *** reconstructs the image into a multi-linked list structure consisting of numerous nodes,where each pixel is transformed into a single node with data and pointer *** employing a special addressing algorithm,the optimal linked list corresponding to the secret information can be *** receiver can restore the secretmessage fromthe received image using only the list header position *** scheme is based on the concept of coverless steganography,eliminating the need for any modifications to the cover *** boasts high concealment and security,along with a complete message restoration rate,making it resistant to ***,this paper proposes linked-list construction schemeswithin theproposedframework,which caneffectively resist a variety of attacks,includingnoise attacks and image compression,demonstrating a certain degree of *** validate the proposed framework,practical tests and comparisons are conducted using multiple *** results affirm the framework’s commendable performance in terms of message reduction rate,hidden writing capacity,and robustness against diverse attacks.

关键词： Steganography encryption steganography without embedding coverless steganography

An Estimation Method for Primary Frequency Regulation Capability of Thermal Power Units Under Deep Peak Load Regulation

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An Estimation Method for Primary Frequency Regulation Capabi...

中小型煤矿智能化建设中机电设备升级改造研究

第22届中国系统仿真技术及其应用学术年会（CCSSTA22nd 2021）

作者： Wang Zijie Hu Huaizhong Zhang Xiaoke Cai Yuanli chen erqiang Xi'an Jiaotong University Electric Power Research Institute of State Grid Henan Electric Power Company

With the wide application of new energy power generation,more and more thermal power units will work under the condition of deep peak *** order to ensure that the primary frequency regulation capacity of the unit can meet the regulation requirements of the power grid,it is of great significance for the modeling of the primary frequency regulation of the unit under the condition of deep peak load *** volume time constant,power distribution coefficient and power overshooting coefficient of each stage in the steam turbine system are the core parameters of the primary frequency regulation *** power distribution coefficient and overshooting coefficient of each cylinder block are considered to be known constants in the traditional primary frequency regulation modeling,but under the condition of deep peak regulation,these coefficients will change with the change of peak regulation *** of the correlation between the power distribution coefficient and the overshooting coefficient,these parameters cannot be identified independently by the mechanism *** this paper,through the equivalent transformation of the turbine model,the turbine mechanism model is transformed into the form of transfer function,and the number of parameters to be identified is *** parameters in the new model can be identified independently,and the identification results show that the model can reflect the actual primary frequency regulation capacity of the unit well.

关键词： Primary Frequency Regulation Deep Peak Regulation Power Distribution Coefficient Power Overshooting Coefficient

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能源与环保 2023年第9期45卷 237-242页

作者：陈二强河南焦煤能源有限公司九里山矿河南焦作454000

在中小型煤矿智能化建设中,机电设备如何升级改造,如何能够与新建设的智能化系统相融合、相匹配,是保证中小型煤矿智能化建设能否持续、有效推进的关键。根据《煤矿安全规程》《河南省煤矿智能化建设标准》《河南省煤矿智能化建设验收... 详细信息

在中小型煤矿智能化建设中,机电设备如何升级改造,如何能够与新建设的智能化系统相融合、相匹配,是保证中小型煤矿智能化建设能否持续、有效推进的关键。根据《煤矿安全规程》《河南省煤矿智能化建设标准》《河南省煤矿智能化建设验收办法》,从煤矿实际出发,在设计过程中,通过各方面的考虑,选取合理改造方案,对机电设备升级改造,满足煤矿智能化建设的可靠性、安全性、经济性及技术合理性的需要,实现了中小型煤矿智能化建设的持续、有效推进。

关键词：中小型煤矿智能化建设机电设备升级改造

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高分子学报 2010年第9期20卷 1136-1142页

作者：于翔陈尔强朱诚身何素琴刘文涛郑州大学材料科学与工程学院郑州450052 北京分子科学国家实验室高分子化学与物理教育部重点实验室北京大学化学与分子工程学院北京100871

用小角/广角X射线散射(SAXS/WAXS)联用的实验方法考察了等温结晶温度(Tc)和等温时间对聚(ε-己内酯)(PCL)片晶形态的影响.根据WAXS数据计算了PCL的重量结晶度,进而求得其体积结晶度Vc(WAXS).在不同Tc下结晶的PCL样品的Vc(WAXS)均略高于5... 详细信息

用小角/广角X射线散射(SAXS/WAXS)联用的实验方法考察了等温结晶温度(Tc)和等温时间对聚(ε-己内酯)(PCL)片晶形态的影响.根据WAXS数据计算了PCL的重量结晶度,进而求得其体积结晶度Vc(WAXS).在不同Tc下结晶的PCL样品的Vc(WAXS)均略高于50%.对SAXS谱线做一维相关函数(1DCF)分析,得到了PCL的片晶长周期(LP)和无定形层厚度(La).通过比较WAXS及SAXS的数据分析结果,认为PCL晶体需用"三相模型"予以描述,其过渡层厚度(E)约为LP的15%～18%,对片晶形态具有重要影响.随着Tc升高,PCL晶体的Lc、La及E均逐渐增大,但Lc的变化率最大,这使得结晶度上升.在50℃等温结晶不同时间,发现Lc随延长时间显著增加,而La及E则不断减小.等温10天后,PCL晶体的SAXS谱线上可观察到5级散射,表明片晶相当完善.

关键词：聚(ε-己内酯) 片晶广角X射线散射小角X射线散射一维相关函数

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Profile of *** chen

Science China(Life Sciences) 2024年第10期67卷 2062-2063页

作者： chen, Songlin Yellow Sea Fisheries Res Inst Qingdao Peoples R China

For decades,*** has been engaged in fish germplasm preservation,sex control and research focusing on molecular breeding for disease *** discovered the first sex-specific molecular marker of fish(chen et al.,2007),deciphered the first fish genome(Chinese tongue sole)in China,revealed the sex determination mechanism in fish(chen et al.,2014),and created molecular sex control *** also discovered the molecular mechanism of metamorphosis in flatfish(Shao et al.,2017)and developed China's first fish disease-resistant breeding gene chip,“YUXIN No.1”.

关键词： technology breeding

不同初始结构间规聚丙烯纤维熔融过程中的结晶转变行为

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高分子学报 2009年第10期19卷 1037-1042页

作者：张秀芹罗发亮李荣波陈尔强王笃金中国科学院化学研究所工程塑料院重点实验室北京100190 宁夏能源化工自治区重点实验室宁夏大学银川740002 北京大学化学与分子工程学院北京100871

通过熔融纺丝及随后的热处理制备了具有不同初始结构的间规聚丙烯纤维(sPP).采用差示扫描量热仪(DSC)和变温广角X-射线衍射仪详细研究了sPP纤维在升温过程中的结构转变和熔融行为.结果表明,不同初始结构sPP纤维的晶型不同,卷绕纤维和退... 详细信息

通过熔融纺丝及随后的热处理制备了具有不同初始结构的间规聚丙烯纤维(sPP).采用差示扫描量热仪(DSC)和变温广角X-射线衍射仪详细研究了sPP纤维在升温过程中的结构转变和熔融行为.结果表明,不同初始结构sPP纤维的晶型不同,卷绕纤维和退火处理纤维以Ⅰ型和Ⅱ型晶型为主,牵伸纤维介晶相占优;升高温度导致Ⅰ型和Ⅱ型两种晶型直接熔融,没有出现Ⅱ型向Ⅰ型的晶型转变;初始结构为介晶相的纤维在升温过程中部分介晶相直接转变为Ⅱ型晶型,还有一部分介晶相直接熔融,并在随后的升温过程中,形成Ⅰ型晶型.sPP纤维的多重熔融行为与其初始结构和纤维制备条件密切相关.

关键词：间规聚丙烯纤维结构转变熔融行为

云母表面上低分子量聚氧乙烯熔体的“假不浸润”行为

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高分子学报 2006年第9期16卷 1125-1128页

作者：朱敦深刘一新陈尔强李明程正迪北京大学化学与分子工程学院高分子科学与工程系高分子化学与物理教育部重点实验室北京100871 中国科学院物理研究所北京100080

The melts of a series of low molecular weight poly（ethylene oxide）（PEO） fractions on mica surfaces were studied by atomic force microscopy（AFM） and X-ray reflectivity（XRR） *** PEO ultrathin films were obtained via static dilute solution *** from the melts of the PEO with both methoxyl（（—OCH3）） end groups that are dewetted on the mica surface,a pseudo-dewetting phenomenon of the PEO melts was observed when either one end group of the PEOs becomes hydroxyl（—OH） or both are hydroxyl *** wetting layer thicknesses of the pseudo-dewetted melts were measured to be 4.5～4.7 nm,independent on the molecular weight and the end groups of ***,the PEO melt droplets on the wetting layer varied from spherical caps with relatively high contact angle to irregular shapes with relatively low contact angle when increasing the molecular weight and the hydrophobicity of end groups of PEOs.

关键词：云母聚氧乙烯假不浸润原子力显微镜 X射线反射率