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The assembly of a composite based on nano-sheet graphene oxide and montmorillonite

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Petroleum Science 2018年第2期15卷 366-374页

作者： yu-Xiu An Wei-Jia Qu pei-zhi yu Jian-Guo Lu School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China

Graphene oxide （GO） nano-sheets were synthesized using a modified Hummers＇ method from graphite powder. The Raman spectrum of GO displayed a D-band at 1359 cm-1 and a G-band at 1594 cm-l. The ID/IG value of GO was calculated to be 0.97, suggesting the formation of new sp2 clusters upon reduction. A method was designed to investigate the assembly of the GO/montmorillonite （MMT） composite. After the addition of GO, the typical peaks of montmorillonite in FT-IR spectra shifted, indicating the assembly between GO and MMT. The D-band and G-band reduced sharply in the GO/MMT composite. More importantly, the D-band （1344 cm-1） and G-band （1574 cm 1） shifted significantly and the ID/ IG value of the GO/MMT composite was calculated to be 1.13, showing a change in the GO structure. In the addition of 0.04 wt% GO to MMT, the value of interlayer space （d） was up to 13.0 Ameasured by XRD due to the insertion of GO into MMT. The evident increases in contents of carbon atoms （26.59%） and nitrogen atoms （3.44%） indicate that GO was successfully combined with MMT. The nano-pores and clay sheets were not observed in the SEM image of GO/clay, but obvious wrinkles, while flexible sheets were observed in the typical scanning electron microscopy images of GO. This further proves that GO was combining with clay. The TEM image shows that the GO nano-sheets were tiled on the surface of MMT sheets. This observation suggests that a stable assembly structure was formed between GO sheets and MMT sheets. The change in particle size of MMT with the addition of GO shows that interaction occurred between GO sheets and MMT sheets, which was further confirmed by the results of zeta potential. Adsorption and insertion were the main mechanisms to assemble GO and MMT.

关键词： Drilling fluid Graphene oxide Montmorillonite Wellbore stability

Low‑Temperature Fabrication of Stable Black‑Phase CsPbI_(3)Perovskite Flexible Photodetectors Toward Wearable Health Monitoring

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Nano-Micro Letters 2025年第3期17卷 232-245页

作者： Yingjie Zhao Yicheng Sun Chaoxin pei Xing Yin Xinyi Li Yi Hao Mengru Zhang Meng yuan Jinglin Zhou yu Chen Yanlin Song College of Chemistry and Pingyuan Laboratory Zhengzhou UniversityZhengzhou 450001People’s Republic of China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Key Laboratory of Bio‑Inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People’s Republic of China

Flexible wearable optoelectronic devices fabricated fromorganic–inorganic hybrid perovskites significantly accelerate the developmentof portable energy,biomedicine,and sensing fields,but their poor thermal stabilityhinders further ***,all-inorganic perovskites possessexcellent thermal stability,but black-phase all-inorganic perovskite filmusually requires high-temperature annealing steps,which increases energy consumptionand is not conducive to the fabrication of flexible wearable *** this work,an unprecedented low-temperature fabrication of stable blackphaseCsPbI3perovskite films is demonstrated by the in situ hydrolysis reactionof diphenylphosphinic chloride *** released diphenyl phosphateand chloride ions during the hydrolysis reaction significantly lower the phasetransition temperature and effectively passivate the defects in the perovskitefilms,yielding high-performance photodetectors with a responsivity of 42.1 AW−1 and a detectivity of 1.3×10^(14)***,high-fidelity imageand photoplethysmography sensors are demonstrated based on the fabricated flexible wearable *** work provides a newperspective for the low-temperature fabrication of large-area all-inorganic perovskite flexible optoelectronic devices.

关键词： In situ hydrolyzation Low-temperature processing All-inorganic perovskite Flexible photodetectors Health monitoring

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang pei-zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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冲击回波主频成像在箱梁孔道压浆检测中的应用

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交通标准化 2011年第22期39卷 173-176页

作者：裴之钰黄燕南京交通职业技术学院江苏南京211188 江苏省高速公路检测中心江苏南京211188

基于冲击回波法检测的基本原理及其目前在土木工程中的应用情况,结合江苏省在建高速公路中对后张法预制箱梁孔道压浆的质量检测需求,通过冲击回波法对箱梁预应力束孔管道的压浆质量进行无损检测,利用冲击回波实测主频的成像,判断后张法... 详细信息

基于冲击回波法检测的基本原理及其目前在土木工程中的应用情况,结合江苏省在建高速公路中对后张法预制箱梁孔道压浆的质量检测需求,通过冲击回波法对箱梁预应力束孔管道的压浆质量进行无损检测,利用冲击回波实测主频的成像,判断后张法预制箱梁孔道预应力束金属波纹管中是否存在空隙。经过凿开验证表明,冲击回波法能准确的定性判断波纹管的位置以及预制箱梁孔道内压浆密实情况,该方法适用于预应力束孔管道的压浆质量检测。

关键词：孔道压浆冲击回波法主频成像压浆密实情况

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水泥混凝土冬期施工的质量控制措施

山西建筑 2007年第8期33卷 222-,246页

作者：黄燕裴之钰南京交通职业技术学院

介绍了水泥混凝土早期受冻损害的机理及对其性能的影响,并对水泥混凝土冬期施工温度的确定与温度应力进行了分析,提出了水泥混凝土冬期施工温度的控制措施及质量控制措施,最后对水泥混凝土冬期施工进行了经济评价,以保证冬期施工的顺利... 详细信息

介绍了水泥混凝土早期受冻损害的机理及对其性能的影响,并对水泥混凝土冬期施工温度的确定与温度应力进行了分析,提出了水泥混凝土冬期施工温度的控制措施及质量控制措施,最后对水泥混凝土冬期施工进行了经济评价,以保证冬期施工的顺利进行。

关键词：水泥混凝土温度应力冬期施工控制措施

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基于虚拟化技术的吉林市气象云平台设计

安徽农业科学 2017年第22期45卷 195-196,227页

作者：庞培林陈治宇吉林省吉林市气象局吉林吉林132011

针对吉林市气象局业务发展中遇到的IT运维难题,结合业务发展和实际工作情况,通过与传统服务器的运维、存储和管理等方式的对比,分析虚拟化技术的各项功能和特点的优势,从而提出了吉林市气象云平台的整体设计方案,此方案显著提高了业务... 详细信息

针对吉林市气象局业务发展中遇到的IT运维难题,结合业务发展和实际工作情况,通过与传统服务器的运维、存储和管理等方式的对比,分析虚拟化技术的各项功能和特点的优势,从而提出了吉林市气象云平台的整体设计方案,此方案显著提高了业务服务器的可用性,加强了IT运维的可管理性,增加了未来业务发展的可拓展性,极大降低了气象信息业务运行成本。

关键词：云计算虚拟化气象云平台设计

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粒细胞减少病人静脉留置套管针留置时间观察

实用护理杂志 2002年第3期18卷 5-6页

作者：朱培莉余志华陈炳英深圳市第二人民医院广东深圳518029

目的　探讨粒细胞减少病人的静脉留置套管针安全留置时间 ,以减少或避免其静脉炎的发生。方法　按粒细胞减少程度将 71例粒细胞减少病人分为 3组 ,对其套管针静脉留置情况进行观察。结果　粒细胞减少的程度与留置套管针的静脉炎发生率... 详细信息

目的　探讨粒细胞减少病人的静脉留置套管针安全留置时间 ,以减少或避免其静脉炎的发生。方法　按粒细胞减少程度将 71例粒细胞减少病人分为 3组 ,对其套管针静脉留置情况进行观察。结果　粒细胞减少的程度与留置套管针的静脉炎发生率成正比 ,3组分别为 4 6 1%、68 3 %、78 9%。结论　静脉留置套管针留置所致的静脉炎与粒细胞减少的程度及留置时间的长短有关 ,提示我们为减少或避免粒细胞减少病人静脉炎的发生。

关键词：粒细胞减少静脉留置套管针留置时间观察

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华南区域秸秆和畜禽粪便有机钾资源调查分析

广东农业科学 2017年第4期44卷 83-89页

作者：黄继川彭智平徐培智涂玉婷广东省农科院农业资源与环境研究所/广东省养分资源循环利用与耕地保育重点实验室/农业部南方植物营养与肥料重点实验室广东广州510640

根据资料查阅统计了华南区域(广东、广西和海南)主要作物秸秆(水稻、玉米、香蕉、甘蔗、花生、薯类、豆类、蔬菜和烟叶)和畜禽粪便(猪、家禽、肉牛、羊、兔、役牛、奶牛和母猪)的资源量及有机K_2O资源量。结果表明,2008—2014年间华南... 详细信息

根据资料查阅统计了华南区域(广东、广西和海南)主要作物秸秆(水稻、玉米、香蕉、甘蔗、花生、薯类、豆类、蔬菜和烟叶)和畜禽粪便(猪、家禽、肉牛、羊、兔、役牛、奶牛和母猪)的资源量及有机K_2O资源量。结果表明,2008—2014年间华南区域年均秸秆资源量为6 571.09万t,广西、广东和海南分别占秸秆资源总量的61.59%、32.53%和19.89%;秸秆K_2O资源量为85.95万t,广西、广东和海南分别占秸秆K_2O资源的48.56%、43.65%和7.78%。在畜禽粪便方面,2010—2014年间华南区域畜禽粪便排泄量年均为19 645.16万t,广西、广东和海南分别占55.42%、36.76%和7.82%;畜禽粪便年均有机K_2O资源总量为65.28万t,广西、广东和海南分别占52.60%、39.32%和8.07%。华南地区有机钾资源体量大,具有很好的挖掘利用前景。

关键词：有机钾秸秆畜禽粪便肥料农业利用

Multi-Field Analysis and Experimental Verification on Piezoelectric Valve-Less Pumps Actuated by Centrifugal Force

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 1032-1043页

作者： yu-Ting Ma zhi-Guo pei Zhong-Xiang Chen CAS Key Lab of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163China

A piezoelectric centrifugal pump was developed previously to overcome the low frequency responses of piezoelectric pumps with check valves and liquid reflux of conventional valveless piezoelectric pumps. However, the electro-mechanical-fluidic analysis on this pump has not been done. Therefore, multi-field analysis and experimen- tal verification on piezoelectrically actuated centrifugal valveless pumps are conducted for liquid transport appli- cations. The valveless pump consists of two piezoelectric sheets and a metal tube with piezoelectric elements pushing the metal tube to swing at the first bending resonant fre- quency. The centrifugal force generated by the swinging motion will force the liquid out of the metal tube. The governing equations for the solid and fluid domains are established, and the coupling relations of the mechanical, electrical and fluid fields are described. The bending res- onant frequency and bending mode in solid domain are discussed, and the liquid flow rate, velocity profile, and gauge pressure are investigated in fluid domain. The working frequency and flow rate concerning different components sizes are analyzed and verified through experiments to guide the pump design. A fabricated pro- totype with an outer diameter of 2.2 mm and a length of 80 mm produced the largest flow rate of 13.8 mL/min at backpressure of 0.8 kPa with driving voltage of 80 Vpp. Bysolving the electro-mechanical-fluidic coupling problem, the model developed can provide theoretical guidance on the optimization of centrifugal valveless pump characters.

关键词： Valveless pump Centrifugal force Piezoelectric pump Multi-field analysis