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A Novel Unsymmetrical Photochromic Diarylethene

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A Novel Unsymmetrical Photochromic Diarylethene

2011 International Conference on Advanced Materials and Computer Science(ICAMCS 2011)

作者： weijun liu Yan Lu Shouzhi Pu Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University

A novel unsymmetrical diarylethene derivative bearing both phenyl and thiophene moieties, in which a chlorine group was substituted at the para-positions of the terminal phenyl ring, was synthesized. At the same time, its photochromic properties and fluorescence switch were investigated in detail. The results showed that this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 541 nm in hexane and at 550 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. The fluorescence intensity of diarylethene decreased dramatically along with the photochromism from open-ring isomer to closed-ring isomer upon irradiation with 297 nm UV light in PMMAIn hexane solution, the open-ring isomer of the diarylethene 1 exhibited relatively strong fluorescence at 462 nm when excited at 316 nm.

关键词： Diarylethene Photochromism Fluorescence Synthesis

OH rotational temperature observed over Beijing,China and compared with TIMED/SABER in mesopause region

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OH rotational temperature observed over Beijing,China and co...

中国空间科学学会空间物理学专业委员会第十五届全国日地空间物理学研讨会

作者： weijun liu Jiyao XU Wei YUAN State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences

The OH spectra ground-based observed over Beijing,China from 2011 to 2012 are used to study the rotational temperature in the mesopause *** Einstein coefficients data sets are used to retrieve rotational *** comparing with TIMED/SABER observations,the Einstein coefficients data sets are *** OH(8-3),the coefficients of Hitran08 are 100%larger than LWR(Longhoff et al.,1986),and the lines ratios of different coefficients data sets could differ 10%,which lead to 10 K’s bias of rotational *** comparison between our ground-based observation and TIMED satellite indicates that the rotational temperatures of OH(8-3&9-4)derived by LWR are consistent with SABER’s observations,but the temperatures of OH(5-1)band calculated with Hitran08 and TL(Turnbull and Lowe,1988)are the closest to SABER’.The seasonal variations of rotational temperatures are *** results show strong Annual Oscillation.

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A New Offset Hatch Path Generation Algorithm for 3D Model Slicing in RP

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A New Offset Hatch Path Generation Algorithm for 3D Model Sl...

第五届全国表面工程学术会议

作者： Jiayi Zhang, weijun liu, Tianran Wang

＜正＞ Rapid Prototyping （RP） is a relatively novel technique to produce prototypes for industry in a shorter period of time. The filling method in our Directed Metal Deposition （DMD） rapid prototyping and manufacturing system directly influences the quality of prototypes. By investigating the geometric properties of domains in a slice, a new reconstruction algorithm of offset boundaries of the contours on STL solid data model slicing is introduced and a Limit for boundaries offsetting is put forth. By these new methods, we can fill regions by the offsetting lines of the boundaries. The performance of the proposed algorithm is discussed based on the connection angle along the path, continuous motion and the forces distributing. Based on the new algorithm, software is programmed in VC++. Its application is fast and efficient.

关键词： rapid prototyping slicing offset boundaries

Synthesis a New Photochromic Diarylethene Based on Five-membered Heterocycle and Hexatomic Ring Aryl for Optical Storage

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Synthesis a New Photochromic Diarylethene Based on Five-memb...

2011 International Conference on Advanced Materials and Computer Science(ICAMCS 2011)

作者： Shiqiang Cui Shouzhi Pu Gang liu weijun liu Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University

A new unsymmetrical photochromic diarylethene 1-[2-cyanophenyl]-2-[（2-methyl-5-（4-methoxyphenyl）-3-thienyl）]perfluorocyclopentene（1a） was synthesized, its photochromic properties were examined, the result indicated that the Diarylethene 1a changed the color from colorless to purple upon irradiation with 297 nm UV light, in which absorption maxima were observed at 550 and 557 nm in hexane and PMMA film, respectivelyThis new photochromic system also exhibited remarkable fluorescence switching in hexane solution and remarkable optical storage character in PMMA film.

关键词： photochromism diarylethene optical storage

The NOxStorage and Desorption Activity of Mg/Al/Cu-NH3·H2O Hydrotalcites at Low Temperature

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Journal of Minerals and Materials Characterization and Engineering 2017年第5期5卷 311-322页

作者： Chunyana liu weijun liu Liwen Wang Yuyingnan liu Chuan Yang Fengbai Zhang Shuhua Zhang College of Mechanical Engineering Shanghai University of Engineering Science Shanghai China College of Chemistry and Chemical Engineering Shanghai University of Engineering Science Shanghai China

Ammonium containing catalyst Mg/Al/Cu-NH3·H2O hydrotalcite (HT) is prepared via co-precipitation, which is effective for NOx storage under 160℃. XRD and FT-IR are employed to characterize its structure and show that ammonium is successfully incorporated into HT. Meanwhile, the HT still retains the typical structure of hydrotalcite-like compounds. NOx storage activity tests indicate Mg/Al/Cu-NH3·H2O HT shows the significant NOx removal activity at 156℃ with a little Oxygen existence. TGA and DTG reveal the reaction of the released ammonium with NOx and storage NOx as nitrates will be responsible for the high NOx storage activity. Additionally, the temperature programmed desorption test of NOx adsorbed sample under 175℃ proves NOx is stored successfully into Mg/Al/Cu-NH3·H2O HT further.

关键词： Hydrotalcites NOx Storage and Desorption TG and DTG Analysis FT-IR Characterization

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非标定立体图像对鲁棒性校正新算法

计算机工程 2006年第5期32卷 26-28页

作者：马永壮刘伟军中国科学院沈阳自动化研究所二室

传统的非标定图像校正都是依赖于基础矩阵的精度。而该方法根据图像校正基本准则,提出一种无需高精度基础矩阵的鲁棒性图像对校正算法,基础矩阵只是提供迭代优化的初始数值,并且与需要基础矩阵的方法相比较,结果表明该方法有效地消除垂... 详细信息

传统的非标定图像校正都是依赖于基础矩阵的精度。而该方法根据图像校正基本准则,提出一种无需高精度基础矩阵的鲁棒性图像对校正算法,基础矩阵只是提供迭代优化的初始数值,并且与需要基础矩阵的方法相比较,结果表明该方法有效地消除垂直视差,能够较好地处理射影畸变问题。

关键词：图像校正基础矩阵射影畸变

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论电信网络诈骗的生态治理——以《反电信网络诈骗法》为主要研究样本

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法学论坛 2023年第4期38卷 94-105页

作者：刘为军中国人民公安大学侦查学院北京100038

电信网络诈骗具有庞大的受害群体,呈现境内境外、线上线下双向联动的空间格局,作案手段有着鲜明时代性,且依附着大量黑灰产,已形成完整的犯罪生态。《反电信网络诈骗法》是对电信网络诈骗治理长期实践的立法确认,以落实“系统治理”“... 详细信息

电信网络诈骗具有庞大的受害群体,呈现境内境外、线上线下双向联动的空间格局,作案手段有着鲜明时代性,且依附着大量黑灰产,已形成完整的犯罪生态。《反电信网络诈骗法》是对电信网络诈骗治理长期实践的立法确认,以落实“系统治理”“依法治理”“综合治理”“源头治理”等“四个治理”为基本定位,但在当下及今后一段时期,其犯罪治理模式仍处在打击治理阶段。在国家治理体系和治理能力现代化视域下,为应对生态化的电信网络诈骗,仍需进一步迈向生态治理,注重治理的法治细节,构筑有深度重实质的协同治理,打破犯罪生态平衡,实现治理生态提级。

关键词：电信网络诈骗依法治理生态治理协同治理

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城市轨道交通5G公专网无线覆盖方案研究

城市轨道交通研究 2024年第4期27卷 206-210,215页

作者：刘为俊中铁第四勘察设计院集团有限公司武汉430063 无锡时代智能交通研究院有限公司无锡214121

[目的]城市轨道交通5G公专网是5G公网在城市轨道交通行业的垂直应用,其无线覆盖方案与5G公网仅需满足公众乘客对移动通信的需求存在较大差异。因此需研究城市轨道交通5G公专网无线覆盖方案。[方法]以城市轨道交通无线通信业务需求为前提... 详细信息

[目的]城市轨道交通5G公专网是5G公网在城市轨道交通行业的垂直应用,其无线覆盖方案与5G公网仅需满足公众乘客对移动通信的需求存在较大差异。因此需研究城市轨道交通5G公专网无线覆盖方案。[方法]以城市轨道交通无线通信业务需求为前提,针对城市轨道交通的复杂应用环境,明确了5G公专网无线覆盖范围,提出了不同应用场景下无线覆盖技术指标要求;设计了隧道区域、地面区域和室内区域不同场景下的无线覆盖方式;探讨了无线网络容量优化和覆盖优化措施。[结果及结论]所形成的以业务需求为导向的城市轨道交通5G公专网无线覆盖方案是全场景、连续性的解决方案。城市轨道交通5G公专网无线覆盖方案还应统筹考虑运营商不同制式、多频段无线系统共建共享及系统之间干扰问题,以为城市轨道交通用户提供良好的5G公专网服务。

关键词：城市轨道交通 5G公专网无线覆盖业务需求网络优化

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超越侦查公开与不公开之争——兼论侦查公正的实现

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中国刑事法杂志 2010年第4期 34-40页

作者：刘为军中国人民公安大学侦查系

侦查不公开是传统侦查原则,但在一系列敏感案件挑战下以及公众以公开求公正的呼吁声中逐步陷入困境。当前更重要的不是在立法上直接规定应以公开或不公开为原则,而应对侦查信息进行等级化管理,基于不同对象和侦查的不同阶段,明确绝对公... 详细信息

侦查不公开是传统侦查原则,但在一系列敏感案件挑战下以及公众以公开求公正的呼吁声中逐步陷入困境。当前更重要的不是在立法上直接规定应以公开或不公开为原则,而应对侦查信息进行等级化管理,基于不同对象和侦查的不同阶段,明确绝对公开、可以公开和绝对不公开的信息类别以及公开的方式,进而构建更合理的侦查程序制度,重建侦查机关与公众之间的信任关系。

关键词：侦查公开侦查不公开信息等级化侦查公正

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