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Nonlinearity-Compensation-Free Optical Frequency Domain Reflectometry Based on Electrically-Controlled Optical Frequency Sweep

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Journal of Electronic Science and Technology 2021年第1期19卷 89-96页

作者： Fan Yang ling-jie zhang Zhi-Yao zhang Xiao-Jun Zhou Yong Liu the School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

A nonlinearity-compensation-free optical frequency domain reflectometry(OFDR)scheme is proposed and experimentally demonstrated based on the electrically-controlled optical frequency *** the proposed scheme,the linear frequency sweep light is generated by propagating an ultra-narrow-linewidth continuous-wave(CW)light through an electro-optic frequency shifter which consists of a dual-parallel Mach-Zehnder modulator(DPMZM)and an electronic 90°hybrid,where the electro-optic frequency shifter is driven by a linear frequency modulated signal generated by a direct digital synthesizer(DDS).Experimental results show that the spatial resolution and signal-to-noise ratio(SNR)of the proposed OFDR scheme without the nonlinear phase compensation are comparable to those of OFDR employing a commercial tunable laser source(TLS),an auxiliary interferometer,and a software-based nonlinear phase compensation *** proposed OFDR scheme is helpful to reduce the complexity of the optical structure and eliminate the difficulty of developing the nonlinear phase compensation algorithm.

关键词： Dual-parallel Mach-Zehnder modulator(DPMZM) electro-optic frequency shifter optical fiber sensor optical frequency domain reflectometry(OFDR)

Neoadjuvant chemoradiotherapy for resectable esophageal carcinoma:A meta-analysis

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World Journal of Gastroenterology 2009年第47期15卷 5983-5991页

作者： Hai-Lin Jin Hong Zhu Ting-Sheng ling Hong-jie zhang Rui-Hua Shi Department of Gastroenterology the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China

AIM:To compare neoadjuvant chemoradiotherapy and surgery with surgery alone for resectable esophageal carcinoma. METHODS:We used MEDLINE and EMBASE databases to identify eligible studies and manual searches were done to ensure no studies were *** validity assessment was performed and a trial quality score was assigned. RESULTS:Eleven randomized controlled trials(RCTs) including 1308 patients were *** chemoradiotherapy significantly improved the overall survival compared with surgery *** ratio(OR) [95%confidence interval(CI),P value],expressed as neoadjuvant chemoradiotherapy and surgery vs surgery alone,was 1.28(1.01-1.64,P=0.05)for 1-year survival,1.78(1.20-2.66,P=0.004)for 3-year survival,and 1.46(1.07-1.99,P=0.02)for 5-year *** mortality increased in patients treated by neoadjuvant chemoradiotherapy(OR: 1.68,95%CI:1.03-2.73,P=0.04),but incidence of postoperative complications was similar in two groups (OR:1.14,95%CI:0.88-1.49,P=0.32).Neoadjuvant chemoradiotherapy lowered the local-regional cancer recurrence(OR:0.64,95%CI:0.41-0.99,P=0.04), but incidence of distant cancer recurrence was similar (OR:0.94,95%CI:0.68-1.31,P=0.73).Histological subgroup analysis indicated that esophageal squamous cell carcinoma did not benefit from neoadjuvantchemoradiotherapy,OR(95%CI,P value)was 1.16(0.85-1.57,P=0.34)for 1-year survival,1.34 (0.98-1.82,P=0.07)for 3-year survival and 1.41 (0.98-2.02,P=0.06)for 5-year survival. CONCLUSION:Neoadjuvant chemoradiotherapy can raise the survival rate of patients with esophageal adenocarcinoma.

关键词： Esophageal carcinoma Neoadjuvant chemoradiotherapy Randomized controlled trial Metaanalysis

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-ling Cui Chuan-Peng zhang Jun-jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

Possible Habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the NH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： Dong Feng Hong-qiang Ru Xu-dong Luo jie-gang You ling zhang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina Liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form

A Simulation Model for Mixing Traffic Flow at An Intersection

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Journal of Systems Engineering and Electronics 1996年第3期7卷 63-68页

作者： Juan Zhicai Chen ling & zhang jie(Jilin Univ. of Technology P.R. China) Jilin Univ. of Technology P.R. China

This paper will develop a model simulation mixing traffic flow in the signal controlintersection. Applying the model, the schemes of traffic channeling and controlling in the typical intersection are analyzed and optimized and the optimal scheme make the average stop frequency be reduced by 31.8% and average stop time be reduced by 27.7%.

关键词： Traffic flow Simulation model.

An Efficient Optimization Design Framework for Low-Resistance Shape of Bionic Amphibious Robot

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China Ocean Engineering 2024年第1期38卷 117-128页

作者： zhang Dai-yu zhang Man-yu WANG Zhi-dong ZHENG Wen-sheng ling Hong-jie HU Jun-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

To realize the low-resistance shape optimization design of amphibious robots,an efficient optimization design framework is proposed to improve the geometric deformation flexibility and optimization *** the proposed framework,the free-form deformation parametric model of the flat slender body is established and an analytical calculation method for the height constraints is *** method is introduced to carry out the high-precision resistance calculation and a constrained Kriging-based optimization method is built to improve the optimization efficiency by circularly infilling the new sample points which satisfying the ***,the shape of an amphibious robot example is optimized to get the low-resistance shape and the results demonstrate that the presented optimization design framework has the advantages of simplicity,flexibility and high efficiency.

关键词： amphibious robot optimization method free-form deformation CFD-based hydrodynamic calculation

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling zhang Yinglong Li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

The inhibitory effect of adenosine on tumor adaptive immunity and intervention strategies

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1951-1964页

作者： Longsheng Wang jie zhang Wenxin zhang Mingming Zheng Hongjie Guo Xiaohui Pan Wen Li Bo Yang ling Ding Zhejiang Province Key Laboratory of Anti-Cancer Drug Research Institute of Pharmacology and ToxicologyCollege of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China The Innovation Institute for Artificial Intelligence in Medicine Zhejiang UniversityHangzhou 310018China Nanhu Brain-Computer Interface Institute Hangzhou 311100China

Adenosine(Ado)is significantly elevated in the tumor microenvironment(TME)compared to normal *** binds to adenosine receptors(AdoRs),suppressing tumor antigen presentation and immune cell activation,thereby inhibiting tumor adaptive *** downregulates major histocompatibility complex II(MHC II)and co-stimulatory factors on dendritic cells(DCs)and macrophages,inhibiting antigen *** suppresses anti-tumor cytokine secretion and T cell activation by disrupting T cell receptor(TCR)binding and signal *** also inhibits chemokine secretion and KCa3.1 channel activity,impeding effector T cell trafficking and infiltration into the tumor ***,Ado diminishes T cell cytotoxicity against tumor cells by promoting immune-suppressive cytokine secretion,upregulating immune checkpoint proteins,and enhancing immune-suppressive cell *** Ado production in the TME can significantly enhance anti-tumor immune responses and improve the efficacy of other *** and clinical development of inhibitors targeting Ado generation or AdoRs is ***,this article will summarize and analyze the inhibitory effects and molecular mechanisms of Ado on tumor adaptive immunity,as well as provide an overview of the latest advancements in targeting Ado pathways in anti-tumor immune responses.

关键词： Adenosine Adenosine receptors Adenosine-generating enzymes Tumor microenvironment Immune suppression Immune escape Clinical treatment Targeting drugs