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Synthesis, Crystal Structure, Physical Properties, and Application of a Series of Functional Dibenzo[d,f][1,3]dioxepine Derivatives

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Chemical Research in Chinese Universities 2008年第6期24卷 798-804页

作者： zhang Hai-quan zhang cheng-bo ZHENG Yan YANG Bing MA Yu-guang State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 P. R. China State Key Lab for Supramolecular Structure and Materials Jilin University Changchun 130012 P. R. China

The twisted aromatics, functional dibenzo[d,f][1,3]dioxepine derivatives were synthesized in high yields from reactions of 5,5＇-dibromo-2,2＇-biphenol with corresponding ketal or ketone compounds under acid catalysis. The structures of these compounds were characterized by ^1H NMR, elemental analysis, UV-Vis absorption spectrum and X-ray diffraction analysis. The conformation of O--C--O bridged biphenyl derivatives with varied substitute groups on 6,6＇-position was studied by X-ray crystallography and force-field simulation. The result of calculations by UNIVERSAL 1.02 force field in Cerius2 package（4.6） indicates that dibenzo[d,f][1,3]dioxepine derivatives show twisted conformations and the twisted angle between the phenyl rings is about 40°, which is accordant with the result from crystal structure determination, though the obtained angles in the crystal of dibenzo[d,f][1,3]dioxepine derivatives with the varied substitute groups on 6,6＇-position are shown to be slightly shifted to 40° owing to intermolecular interactions in crystal stacking. DSC studies exhibit that the substitute groups on 6,6＇-position can induce a large variation of endothermic peaks ranging from 80 to 135 ℃. The conjugated polymers based on dibenzo[d,f][1,3]dioxepine derivatives, which have ultraviolet emitting with a quantum efficiency of 10%, were obtained by Yamamoto coupling.

关键词： Dibenzo[d,f]dioxepine Twisted angle Crystal structure Twisted conformation Ultraviolet emission

Solitary fibrous tumor: a 10-year retrospective analysis with several rare cases

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Chinese Medical Journal 2021年第8期134卷 1006-1008页

作者： Ke zhang Hui-Juan Liu zhang-bo cheng Mi Deng Jing Luo Xin Qi Departm ent of Pathology the Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Department of Ophthalmology the Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Hunan Clinical Research Center of Ophthalmic Disease ChangshaHunan 410011China Department of Cardiovascular Surgery Fujian Provincial HospitalFujian Medical SchoolFuzhouFujian 350001China

To the Editor:Solitary fibrous tumors(SFTs)are mesenchymal neoplasms and were first described in pleura,then subsequently found in extrapleural organs,such as peritoneum,lung,parotid gland,paranasal sinuses,orbit,skin,and intracranial areas.1 However,extrapleural SFTs are limited to isolated case *** of the rarity of them,the related information is far from sufficient and thus,leading this tumor under fully *** to the World Health Organization(WHO)classification,SFTs are pluripotent neoplasms that could be benign,intermediate,or *** of above drive us to further understand the epidemiology,clinical characteristics,medical therapy,and prognosis of this disease.

关键词： neoplasms epidemiology organs

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun zhang Wen-Wei Wang Jing-Shui Zhen bo-cheng Li De-cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Efficacy of endoscopic therapy for gastrointestinal bleeding from Dieulafoy’s lesion

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World Journal of Gastroenterology 2011年第10期17卷 1368-1372页

作者： Jun Cui Liu-Ye Huang Yun-Xiang Liu bo Song Long-Zhi Yi Ning Xu bo zhang cheng-Rong Wu Department of Gastroenterology Yantai Yu Huang Ding Hospital Yantai 264000 Shandong Province China

AIM： To investigate the endoscopic hemostasis for gastrointestinal bleeding due to Dieulafoy＇s lesion. METHODS： One hundred and seven patients with gastrointestinal bleeding due to Dieulafoy＇s lesion were treated with three endoscopic hemostasis methods： aethoxysklerol injection （46 cases）, endoscopic hemoclip hemostasis （31 cases）, and a combination of hemoclip hemostasis with aethoxysklerol injection （30 cases）. RESULTS： The rates of successful hemostasis using the three methods were 71.7% （33/46）, 77.4% （24/31） and 96.7% （29/30）, respectively, with significant differences between the methods （P 〈 0.05）. Among those who had unsuccessful treatment with aethoxysklerol injection, 13 were treated with hemoclip hemostasis and 4 underwent surgical operation; 9 cases were successful in the injection therapy. Among the cases with unsuccessful treatment with hemoclip hemostasis,7 were treated with injection of aethoxysklerol and 3 cases underwent surgical operation; 4 cases were successful in the treatment with hemoclip hemostasis. Only 1 case had unsuccessful treatment with a combined therapy of hemoclip hemostasis and aeth- oxysklerol injection, and surgery was then performed. No serious complications of perforation occurred in the patients whose bleeding was treated with the endoscopic hemostasis, and no releeding was found during a 1-year follow-up. CONCLUSION： The combined therapy of hemoclip hemostasis with aethoxysklerol injection is the most effective method for gastrointestinal bleeding due to Dieulafoy＇s lesion.

关键词： Dieulafoy's lesion Gastrointestinal bleeding Endoscopic therapy Aethoxysklerol Therapeutic efficacy

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审思小学低年级阶段的“三替”现象

教学与管理 2019年第29期 8-9页

作者：张伯成吉林省教育学院

小学阶段是个体从家庭单一主体生活环境向家庭与学校复合主体生活环境转变的重要过程,也是小小少年摸索着学习系好人生第一粒扣子的关键期。而小学低年级是学生群体调整生活模式、适应校园集体生活的过渡期。这一阶段的家庭生活模式与... 详细信息

小学阶段是个体从家庭单一主体生活环境向家庭与学校复合主体生活环境转变的重要过程,也是小小少年摸索着学习系好人生第一粒扣子的关键期。而小学低年级是学生群体调整生活模式、适应校园集体生活的过渡期。这一阶段的家庭生活模式与校园集体牛活模式之间不是简单的衔接关系,而是一种转变,甚至是一种变革。

关键词：小学低年级家庭与学校生活环境生活模式集体生活复合主体单一主体小学阶段

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“走班制”背景下“走班式”家长会模式探讨

教学与管理 2019年第28期 23-25页

作者：张伯成吉林省教育学院

新一轮高考改革意味着新变化。面对传统行政班的消失或是弱化,走班制开始逐渐兴起,传统家长会模式所具有的过度程序化、形式化以及单向输入等问题势必需要进行相应的模式调整。通过分析传统家长会所面临的境遇,深入挖掘其内涵与国外可... 详细信息

新一轮高考改革意味着新变化。面对传统行政班的消失或是弱化,走班制开始逐渐兴起,传统家长会模式所具有的过度程序化、形式化以及单向输入等问题势必需要进行相应的模式调整。通过分析传统家长会所面临的境遇,深入挖掘其内涵与国外可参考的模式,分别从家长、教师、学校等三方主体视角,以"走班式"为基础背景探讨家长会模式的深化发展。

关键词：走班制家长会模式

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面向分布式图计算作业的容错技术研究综述

软件学报 2021年第7期32卷 2078-2102页

作者：张程博李影贾统北京大学软件与微电子学院北京102600 北京大学软件工程国家工程研究中心北京100871 北京大学信息科学技术学院北京100871

随着图数据规模的日益庞大和图计算作业的日益复杂,图计算的分布化成为必然趋势.然而图计算作业在运行过程中面临着分布式图计算系统内外各种来源的非确定性所带来的严峻的可靠性问题.首先分析了分布式图计算框架中不确定性因素和不同... 详细信息

随着图数据规模的日益庞大和图计算作业的日益复杂,图计算的分布化成为必然趋势.然而图计算作业在运行过程中面临着分布式图计算系统内外各种来源的非确定性所带来的严峻的可靠性问题.首先分析了分布式图计算框架中不确定性因素和不同类型图计算作业的鲁棒性,并提出了基于成本、效率和质量3个维度的面向分布式图计算作业的容错技术评估框架,然后分别对分布式图计算的4种容错机制——基于检查点的容错、基于日志的容错、基于复制的容错、基于算法补偿的容错等机制结合国内外相关工作做了深入的分析、评估和比较.最后对未来的研究方向进行了展望.

关键词：图数据故障和失效分布式图计算容错机制非确定性软件系统

一类具有非对称特性的隔振装置结构参数实验辨识方法

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振动与冲击 2013年第6期32卷 18-23页

作者：张呈波张晓旭宋汉文同济大学航空航天与力学学院上海200092 复旦大学力学与工程科学系上海200433

由于重力或装配应力等偏置力的影响,隔振元件的工作状态将会偏离原始平衡位置,进而产生具有非对称特性的动力学行为,其具体表现为系统的动态响应存在刚性漂移现象,且该刚性漂移的大小与外激励频率、幅值均存在复杂的关系;其次,由于振动... 详细信息

由于重力或装配应力等偏置力的影响,隔振元件的工作状态将会偏离原始平衡位置,进而产生具有非对称特性的动力学行为,其具体表现为系统的动态响应存在刚性漂移现象,且该刚性漂移的大小与外激励频率、幅值均存在复杂的关系;其次,由于振动传感器主要针对动态信号,对于零频附近的低频信号存在灵敏度低、测量误差大的缺陷。因而,对于系统响应中存在的刚性漂移信号,实验中往往无法准确测定,甚至可能丢失,这将给系统的动力学参数标定带来非常大的影响。本文针对该问题,建立了此类隔振实验装置的非对称动力学模型,并利用较为成熟的谐波平衡原理构造了一种简单的迭代算法,使其在刚性漂移信息缺失的情况下,仍然能够有效地辨识得到系统结构参数。通过数值仿真,验证了该算法的有效性,并将其应用于一款具体的隔振元件动力学参数辨识工作中。其结果表明,由该算法辨识得到的结构参数与系统真实动力学特性具有较高的吻合度,对于其它具有类似特性的隔振元件的设计及应用具有一定的参考价值。

关键词：非线性系统参数辨识谐波平衡非对称刚性漂移

兰新高速铁路风沙区段挡沙墙设计参数试验研究

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铁道标准设计 2016年第9期60卷 4-8页

作者：张乘波兰新铁路新疆有限公司乌鲁木齐830000

兰新二线风沙路基主要集中于烟墩风区及百里风区,大风条件下极易形成风沙流,挡沙墙是解决风沙对铁路危害的主要措施。为充分发挥挡沙墙的防风沙作用,针对兰新高速铁路沿线风沙流成因及规律进行分析,对挡沙墙高宽比、孔隙率和高度3个参... 详细信息

兰新二线风沙路基主要集中于烟墩风区及百里风区,大风条件下极易形成风沙流,挡沙墙是解决风沙对铁路危害的主要措施。为充分发挥挡沙墙的防风沙作用,针对兰新高速铁路沿线风沙流成因及规律进行分析,对挡沙墙高宽比、孔隙率和高度3个参数分别进行对比试验,提出适合该地区铁路防沙的挡沙墙优化设计思路。结果表明:当挡沙墙高度一定时,风沙防护效果与挡沙墙的宽度显现出一定的负相关变化;对于均匀结构的网状沙障来说,孔隙率为40%的防沙效果最优,30%的次之,50%的相对最差;从不同高度挡沙墙的风沙防护效果来看,高度为2.0 m的挡沙墙的风沙防护效果相对较好,高度为2.5 m和1.5 m挡沙墙防沙效果略差。

关键词：高速铁路挡沙墙设计参数防沙效果