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Impact of Mo/Ni alloying on microstructural modulation and low-temperature toughness of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1746-1762页

作者： Wei Liu Hong-li zhao Bing-xing Wang Yong tian State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

The high-strength low-alloy steel plates with varying Ni/Mo contents were manufactured using the thermos-mechanical control *** investigation was conducted to explore the effect of Ni/Mo microalloying on microstructure evolution and mechanical properties of the *** results revealed that the increase in Ni content from 1 to 2 wt.%reduced the transition temperature of ferrite and the growth range of ferritic grain was narrowed,which promoted grain *** optimized combination of grain size,high-angle grain boundaries(HAGBs),and martensite-austenite(M-A)islands parameter contributed to the excellent impact toughness of S1 steel at-100℃(impact absorbed energy of 218.2 J at-100℃).As the Mo increases from 0 to 2 wt.%,the matrix structure changes from multiphase structure to granular bainite,which increases the average effective grain size to~4.62 pm and reduces HAGBs proportion to~36.22%.With these changes,the low-temperature impact toughness of S3 steel is *** addition,based on the analysis of the characteristics of crack propagation path,it was found that M-A islands with low content(~2.21%)and small size(~1.76 pm)significantly retarded crack propagation,and the fracture model of M-A islands with different morphologies was further ***,correlation between behaviour of delamination and toughness was further analysed by observing delamination size and impact energy parameters.

关键词： High-strength low-alloy steel Microstructural regulation Ni addition Mo addition Crack propagation Low-temperature toughness

Expo Puts Shaoxing on the Textile Industry Map

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China Today 2008年第2期57卷 80-81页

作者： tian xing zhao CUI

THE China Shaoxing Inter- national Textile Expo has become an annual must-see event for those in the textiles industry-a four-day whirlwind of the latest fabrics,machinery,and textile sci- ence and *** fashion shows a... 详细信息

关键词：中国绍兴国际纺织品博览会服装展览纺织工业纺织机械

Transmission spectrum method to measure the photonic bandgap of hollow-core photonic crystal fiber

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Optoelectronics Letters 2007年第1期3卷 22-24页

作者： WEI Hong-yan HOU Lan-tian zhao xing-tao LIU zhao-lun WANG Wei MA Jing-rui Institute of Infrared Optical Fibers and Sensors Yanshan University Qinhuangdao 066004 China

A full-vector plane-wave method is introduced, particularly in calculating the photonic crystal in-plane photonic bandgap of a 2D triangular structure. Using numerical simulation, we can obtain the in-plane bandgap structure of a hollow-core photonic crystal fiber. In the experiments, we measured the transmission spectra of a hollow-core photonic crystal fiber and a silica rod. And using the numerical calculation we can get the relative transmission spectrum of a hollow-core photonic crystal fiber. Compared with the result of theoretical simulation, we found that they are in accordance with each other, i.e. they have the same bandgap in about the same normalized frequency.

关键词：空芯光子晶体光纤光子带隙测量透射谱法

Time-series analysis of the relationship between air quality, temperature, and sudden unexplained death in Beijing during 2005-2008

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Chinese Medical Journal 2012年第24期125卷 4429-4433页

作者： tian zhao-xing ZHANG Yan-shen YAN Wei zhao Wen-kui Department of Emergency Medicine Peking University Third Hospital Beijing 100191 China Center for Environmental Risk and Damage Assessment Chinese Academy of Environmental Planning Beijing 100012 China Department of Respiratory Medicine Peking University Third Hospital Beijing 100191 China Department of Education Peking University Third Hospital Beijing 100191 China

Background There is a yearly increase in the rate of sudden unexplained death （SUD）, even through extensive physical examination and the testing of a large number of biomarkers, the cause of sudden death in patients previously in good health cannot be fully determined. During clinical practice, a spatial aggregation phenomenon has been observed in the incidence of sudden unexplained death. Previous research has shown that environmental factors, such as air pollution, weather conditions, etc., have a significant impact on human health. In the wake of the continuous environmental damage, the relationship between environmental factors and sudden unexplained death still needs to be studied. To study the relationship between sudden unexplained death and air quality and temperature, commonly used markers such as particulate matter of aerodynamic diameter 〈10 μm （PM10）, daily average concentration of the gaseous pollutants sulfur dioxide （SO2） and nitrogen dioxide （NO2）, and the daily average temperature were investigated. Methods The methods include collecting the data of sudden unexplained death; air quality monitoring; meteorological monitoring from January 1, 2005 to December 31, 2008; utilizing generalized additive models （GAM）; controlling the influential factors such as secular trend, seasonal trend, and Sunday dummy variable; and analyzing the correlation between daily inhalable particle concentration, daily average temperature, and the number of daily SUD. Results There was no statistical significance between the daily inhalable particle and daily incidence of sudden unexplained death. Incidence rate of sudden unexplained death had nonlinear positive correlation with daily temperature. When the temperature was 5℃ above the daily average temperature, the daily incidence of sudden unexplained death went up with the rising temperature. Conclusion Temperature may be one of the key risk factor or precipitating factor of SUD.

关键词： air quality temperature sudden unexplained death time-series analysis

Shaoxing County:an Economy Based on Fabrics

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China Today 2007年第9期56卷 80-81页

作者： tian xing&zhao CUI

SHAOxing County in Zhe-jiang Province is famous forits China Light and TextileIndustrial City(CLTIC)。

关键词：绍兴市城市建设经济发展纺织业

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG Long zhao tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Topologically protected entanglement switching around exceptional points

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Light(Science & Applications) 2024年第8期13卷 1631-1644页

作者： Zan Tang tian Chen xing Tang Xiangdong Zhang Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081 BeijingChina

The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and ***,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional *** encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high *** to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling ***,we have experimentally validated such a scheme on a quantum walk *** work opens up a new way for the application of non-Hermitian physics in the field of quantum information.

关键词： exceptional quantum Riemann

Polyethylene imine functionalized porous carbon framework for selective nitrogen dioxide sensing with smartphone communication

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Chinese Chemical Letters 2024年第9期35卷 432-436页

作者： Xiaxia xing Xiaoyu Chen Zhenxu Li Xinhua zhao Yingying tian Xiaoyan Lang Dachi Yang tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Engineering Research Center of Thin Film Optoelectronics TechnologyMinistry of Education and Department of ElectronicsCollege of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

Highly selective and remotely communicable nitrogen dioxide(NO_(2))sensing may contribute to future Internet of Things in environmental ***,room-temperature NO_(2)sensing materials such as carbon materials is still less than satisfactory due to their insensitive interaction with target ***,polyethylene imine functionalized three-dimensional(3D)carbon framework(PEI/C framework)has been developed for enhanced selective NO_(2)sensing,via combined template synthesis and subsequent ***,the 3D PEI/C framework is observed porous shape with irregular ***,the response of C framework to NO_(2)increases while those of interfering gases decrease after being functionalized with ***,the sensor prototypes show a 100 ppb-concentration detection limit at room ***,such excellent NO_(2)sensing is attributed to the large specific surface ratio of porous 3D PEI/C framework,in which PEI serves as an active layer for target NO_(2),while a passivated one for interfering ***,such PEI/C framework sensor prototype is simulated for NO_(2)sensing device and communicated with a smartphone,showing great potential in future intelligent environmental monitoring.

关键词： PEI/C framework Nitrogen dioxide sensing Enhanced selectivity Smartphone communication Practical monitoring simulation

Analysis of the prodromal symptoms of unexplained sudden death in patients with or without underlying diseases

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Chinese Medical Journal 2012年第20期125卷 3619-3623页

作者： tian zhao-xing LÜYan-yu YAN Wei zhao Wen-kui LI Xuan Department of Emergency Medicine Beijing 100191China Department of Respiratory Disease Beijing 100191China Department of Education Beijing 100191China Peking University Third Hospital Beijing 100191China Department of Health Development Capital-Institute of PediatricsBeijng 100020China

Background In recent years, the incidence of unexplained sudden death has risen significantly across the world. However, it occurred suddenly, often in young apparently healthy individuals and almost 50% of the patients did not have any warning signals or symptoms. Therefore, the prodromal symptoms before the incident are extremely important for early prediction of sudden death. In this article, we aimed to explore the value of prodromal symptoms for unexplained sudden death and whether the prodromal symptoms have a predictive function to unexplained sudden death （USD） without underlying diseases. Methods A total of 208 sudden death cases were selected for the survey in the Emergency Department of Peking University Third Hospital from January 2006 to December 2009 and their medical records were reviewed. The patients were divided into two groups, 65 patients had underlying diseases while 143 had not underlying diseases. In the meantime, their prodromal symptoms were collected and compared, prodromal symptoms including chest distress, dyspnea, syncope, fever, headache, vomiting, etc. Results Patients with underlying diseases were compared to those without underlying diseases associated with sudden death; there was no significant difference in gender and age distribution. Among the 208 cases, 39 cases （18.75%） had prodromal symptoms, patients with underlying diseases had prodromal symptoms in 12 cases （18.46%）, while patients without underlying diseases had prodromal symptoms in 27 cases （18.88%）. The difference between the two groups with prodromal symptoms was not statistically significant （P 〉0.05）. Conclusions Prodromal symptoms are extremely important warning signals in the occurrence of USD. It has equally important predictive value for patients both with and without underlying diseases, especially in predicting sudden death caused by cardiopulmonary and neurological diseases.

关键词： prodromal symptoms " unexplained sudden death " early-warning function