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聚乙二醇对硅酸盐胶黏剂适用期与性能的影响

硅酸盐通报 2024年第1期43卷 317-328页

作者：沈镇强王玉丹曹先启宋来明薛金龙王超哈尔滨工程大学材料科学与化学工程学院哈尔滨150000 黑龙江省科学院石油化学研究院哈尔滨150000

为解决硅酸盐胶黏剂在空气中裸露时表面固化成膜导致的适用期过短问题,向硅酸盐胶黏剂中加入聚乙二醇(PEG)进行改性,使用流变仪、扫描电子显微镜、红外光谱仪、热重红外质谱联用仪和万能拉力机系统研究了胶黏剂的适用期、流变性能、微... 详细信息

为解决硅酸盐胶黏剂在空气中裸露时表面固化成膜导致的适用期过短问题,向硅酸盐胶黏剂中加入聚乙二醇(PEG)进行改性,使用流变仪、扫描电子显微镜、红外光谱仪、热重红外质谱联用仪和万能拉力机系统研究了胶黏剂的适用期、流变性能、微观形貌、分子结构、热稳定性及粘接性能。结果表明:当硅酸盐胶黏剂中PEG掺量为6%(质量分数)时,适用期延长至50 min;PEG在胶黏剂内部分布均匀,显著改变了胶黏剂的致密性与触变性;由Arrhenius方程计算出的预固化活化能由8.47 kJ/mol提高至12.61 kJ/mol;PEG不影响体系粘接性能,对同类型硅酸盐胶黏剂适用期也具有良好的延长效果。

关键词：硅酸盐胶黏剂聚乙二醇适用期流变性能粘接性能

Jet Characteristics and Optimization of a Cavitation Nozzle for Hydraulic Fracturing Applications

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Fluid Dynamics & Materials Processing 2024年第1期20卷 179-192页

作者： Yu Gao zhenqiang Xu Kaixiang shen shenzhen South China Sea Oil Economic Development Co. Ltd.Shenzhen518000China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou511458China National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou511458China

Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perforation *** this study,the flow behavior of the nozzle is simulated numerically in the framework of a SST k-ωturbulence *** results show that the nozzle structure can significantly influence the jet performance and related cavitation *** orthogonal experiments,the nozzle geometric parameters are optimized,and the following configuration is found accordingly:contraction angle 20°,contraction segment length 6 mm,cylindrical segment diameter 6 mm,cylindrical segment length 12 mm,spread segment length 10 mm,and spread angle 55°.

关键词： Cavitation jet angle nozzle hydraulic characteristics nozzle parameters

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光纤光栅法布里-珀罗传感器频分复用技术

光学学报 2007年第7期27卷 1173-1177页

作者：沈震强赵建林张晓娟西北工业大学理学院光信息科学与技术研究所陕西省光信息技术重点实验室西安710072

理论分析了光纤光栅法布里-珀罗(F-P)传感器频分复用技术的原理,并给出了信号处理对腔长选取的要求。数值模拟结果表明,不同腔长的传感器具有不同的谐振条纹频率,为保证频域中的信号不发生重叠,要求不同光纤光栅法布里-珀罗传感器间的... 详细信息

理论分析了光纤光栅法布里-珀罗(F-P)传感器频分复用技术的原理,并给出了信号处理对腔长选取的要求。数值模拟结果表明,不同腔长的传感器具有不同的谐振条纹频率,为保证频域中的信号不发生重叠,要求不同光纤光栅法布里-珀罗传感器间的腔长之差必须大于光纤光栅的长度。进一步的实验及模拟分析结果发现,温度等待测量的变化仅仅使光纤光栅法布里-珀罗传感器的反射光谱整体平移,相应的频域信号只产生相移而形状不发生变化,因而不能采用普通光纤法布里-珀罗(FFP)传感器的腔长傅里叶变换解调法解调频分复用光纤光栅法布里-珀罗传感器的信号。根据这一特点,提出了利用自相关分析实现频分复用传感器系统信号解调的方案。

关键词：光纤光学法布里-珀罗传感器频分复用光纤光栅

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一种低损耗、弯曲不敏感光纤

光通信技术 2017年第6期41卷 60-62页

作者：姜丽王亚玲沈震强肖华马建强江苏亨通光导新材料有限公司江苏苏州215200

设计了含有沟槽辅助结构的低损耗、弯曲不敏感光纤——G.657B3光纤,采用轴向气相沉积法(VAD)制备芯棒,套管法(RIC)制备预制棒,实现了G.657B3光纤的设计和制造,并对该光纤的各项性质进行了实验测试。

关键词：沟槽辅助低损耗弯曲不敏感 G.657B3

Application of Molecular Biology and Nanotechnology in Bioaerosol Field

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Application of Molecular Biology and Nanotechnology in Bioae...

Flow Resistance Modeling for Coolant Distribution within Canned Motor Cooling Loops

第六届全国环境化学大会暨环境科学仪器与分析仪器展览会

作者： Fangxia shen,zhenqiang Xu,Qi Chen,Yan Wu,and Maosheng Yao~* (Principal Contact:Maosheng Yao,Professor,1State Key Joint Laboratory for Environmental Simulation and Pollution Control,College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China,]

＜正＞Numerous threats from biological aerosol exposures,such as H1N1 influenza,SARS,bird flu,and bio-terrorism necessitate the development of a real-time bioaerosol sensing system, which however is a long standing challenge in the ***,we reported real-time detection of airborne influenza H3N2 viruses by integrating electrically addressable silicon nanowire（SiNW） sensor devices with microfluidics and a bioaerosol-to-hydrosol air sampling *** A viruses were

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 210-220页

作者： shengde Wang zhenqiang Yao Hong shen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Taylor–Couette–Poiseuille(TCP)flow dominates the inner water-cooling circulation of canned motor reactor coolant *** research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and ***,research on axial flow resistance in a large Reynolds number turbulent state is not sufficient,especially for the various flow *** study is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cylinders of the stator and rotor in canned motor reactor coolant pumps,and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe *** axial flow resistance,coupled with the annular rotation,is experimentally investigated at a flow rate with an axial Reynolds number,Rea,from 2.6×10~3 to 6.0×10~3 and rotational Reynolds number,Ret,from 1.6×10~4 to 4.0×10~*** is revealed that the axial flow frictional coe cient varies against the axial flow rate in linear relation sets with logarithmic coordinates,which shift up when the flow has a higher *** examination of the axial flow resistance,with the Rea extending to 3.5×10~5 and Ret up to 1.6×10~5,by simulation shows gentle variation rates in the axial flow frictional coe cients against the *** relation curves with different Ret values converge when the Rea exceeds 3.5×10~5.A prediction model for TCP flow consisting of a polygonal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Reynolds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure.

关键词： Flow resistance Rotating effect Reynolds numbers Taylor–Couette–Poiseuille flow Canned motor

WAVE FUNCTION OF THE UNIVERSE FOR THE SPINOR FIELD IN THE INDUCED THEOBY OF GRAVITY

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Chinese Physics Letters 1989年第7期6卷 289-292页

作者： shen Yougen TAN zhenqiang Shanghai Observatory Academia SinicaShanghai Center of Theoretical Physics CCAST(World Lab.Beijing)Department of PhysicsGuangxi UniversityNanning

The wave function of the universe for the spinor field in the induced theory of gravity is solved by using Hartle and Hawking *** wave function obeys the Wheeler-De Witt *** results indicate that the spinor field affects strongly the wave function related to the initial condition when like-scalar factor a is very small,and the behavior of the spinor field resembles scalar field when like-scalar factor ot is great.

关键词： equation method scalar

Recent Advances of Electrochemiluminescent System in Bioassay

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Journal of Analysis and Testing 2020年第2期4卷 57-75页

作者： Mengyuan Chen zhenqiang Ning Kaiyang Chen Yuanjian Zhang Yanfei shen Medical School School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing 210009China

Electrochemiluminescent(ECL)technique has drawn increasing attention in a myriad of applications ranging from clinic diagnosis to the environment and food *** advantages of ECL sensors include high sensitivity,negligible background,and excellent controllability with respect to its *** past 2 years have witnessed an impetus in the rise of a batch of luminophores and coreactants as advanced materials to boost the ECL *** the review,we summarize the latest progress of new ECL biosensing systems,in particular of emerging luminophores,coreactants,and the involved *** limitations and exciting future developments of the ECL biosensing are also complementarily *** is highly envisioned that the review article would inspire more intriguing advances both in the fundamental research and more demanding practical applications of ECL for prospective biosensing.

关键词： Electrochemiluminescence Emitters Coreactants Mechanism Biosensors

孕期微生物组的时空模式及其与妊娠期综合征的联系

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Science Bulletin 2024年第9期69卷 1275-1285页

作者：肖力文周田左振强孙宁霞赵方庆 Beijing Institutes of Life Science Chinese Academy of SciencesBeijing 100101China Department of Reproductive Medicine Second Afﬁliated Hospital of Naval Medical UniversityShanghai 200003China Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China University of Chinese Academy of Sciences Beijing 100049China

The microbiome of females undergoes extensive remodeling during pregnancy, which is likely to have an impact on the health of both mothers and offspring. Nevertheless, large-scale integrated investigations characterizing microbiome dynamics across key body habitats are lacking. Here, we performed an extensive meta-analysis that compiles and analyzes microbiome profiles from >10,000 samples across the gut,vagina, and oral cavity of pregnant women from diverse geographical regions. We have unveiled unexpected variations in the taxonomic, functional, and ecological characteristics of microbial communities throughout the course of pregnancy. The gut microbiota showed distinct trajectories between Western and non-Western populations. The vagina microbiota exhibited fluctuating transitions at the genus level across gestation, while the oral microbiota remained relatively stable. We also identified distinctive microbial signatures associated with prevalent pregnancy-related disorders, including opposite variations in the oral and gut microbiota of patients with gestational diabetes and disrupted microbial networks in preterm birth. This study establishes a comprehensive atlas of the pregnancy microbiome by integrating multidimensional datasets and offers foundational insights into the intricate interplay between microbes and host factors that underlie reproductive health.

关键词： Pregnancy microbiome Data integration Spatiotemporal patterns Microbial biomarkers