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Flame behavior, shock wave, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide/air cloud detonation

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Defence Technology（防务技术） 2023年第7期25卷 18-32页

作者： Cong-liang ye Qing-lei Du Li-juan Liu Qi Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Safety Science and Emergency Management Wuhan University of TechnologyWuhanHubei430070China

Energy output and heating effects are essential for vapor-liquid fuel/air cloud detonation in the fuel-air explosive(FAE) applications or explosion accidents. The purpose of this study is to examine the dynamic large-size flame behavior, shock wave propagation law, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide(PO)/air cloud detonation. Based on computational fluid dynamics(CFD) and combustion theory, a numerical simulation is used to study the detonation process of a PO/air cloud produced by a double-event fuel-air explosive(DEFAE) of 2.16 kg. The large-scale flame behavior is characterized. The flame initially spreads radially and laterally in a wing shape. subsequently,the developed flame increases with a larger aspect ratio. Moreover, the propagation laws of shock waves at different heights are discussed. The peak pressure of 1.3 m height level with a stepwise decline is obviously different from that of the ground with an amplitude of reversed ’N’ shape. In the vast majority of the first 6.9 m, the destructive effect of the shock wave near the ground is greater than that of the shock wave at 1.3 m height. Furthermore, the dynamic instantaneous isothermal field is *** scaling relationship of various isotherms in the instantaneous thermal field with the flame and initial cloud is summarized. The comprehensive numerical model used in this study can be applied to determine the overpressure and temperature distribution in the entire fuel/air cloud detonation field,providing guidance for assessing the extent of damage caused by DEFAE detonation.

关键词： Numerical simulation Fuel-air explosive Fuel/air cloud Flame Shock wave Thermal field

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Revisiting the methods of determining hydraulic conductivity of saturated expansive clays in low-compressibility zone

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1131-1136页

作者： Wei su Yu-Jun Cui Feng Zhang Weimin ye Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China Ecole des Ponts ParisTech UR Navier/CERMES6-8av.Blaise PascalCitéDescartesMarne-la-Vallée77455France

The hydraulic conductivity of saturated clays is commonly determined either directly by monitoring water flux or indirectly based on Terzaghi’s consolidation *** results are generally obtained from the two methods,but sometimes a significant difference can be observed,in particular for expansive *** this study,the hydraulic conductivities determined by the two methods are first compared based on existing data in the *** indirect method is then revisited attempting to explain the difference identified.A modified effective stress,considering physico-chemical interaction between face-to-face oriented particles,is finally introduced to better describe the compressibility of expansive clays and to further improve the indirect method in determining hydraulic conductivity of such soils in the low-compressibility *** tests were performed on Gaomiaozi(GMZ)bentonite slurry and the results obtained allowed the modified indirect method to be verified.

关键词： Expansive clays Laboratory tests Hydraulic conductivity Terzaghi’s consolidation equation Modified effective stress

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Ocular findings in syndromic gingival fibromatosis: a case study and electronic microscopic investigation of lens

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 574-576页

作者： ye-Lei Tang Xing-Chao Shentu su-juan Zhao Xia-Jing Tang Long He Fei-Yun Ping Department of Neurology Second Affiliated Hospital of the Medical College Zhejiang University Eye Center Second Affiliated Hospital of the Medical College Zhejiang University Department of Stomatology Second Affiliated Hospital of the Medical College Zhejiang University

We report a case of syndromic gingival fibromatosis with notable ocular lesions,bilateral congenital cataracts,esotropia,and high myopia of a 21-year-old male patient from *** patient was diagnosed with gingival fibromatosis based on his massive gingival overgrowth and histological findings that were consistent with gingival fibromatosis through a gingival *** opacity features were presented and phacoemulsificaion with intraocular lens(IOL)implantation was performed to manage the cataracts in both *** electronic microscopy was used to investigate the ultrastructure of the removed lens *** also review the literature on gingival fibromatosis and briefly summarize the ocular manifestations of this rare disease.

关键词： congenital cataract transmission electron microscopy gingival fibromatosis syndrome

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Model⁃Free Predictive Control for a Kind of High Order Nonlinear Systems

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Journal of Harbin Institute of Technology(New Series) 2022年第2期29卷 62-69页

作者： ye Tian Baili su School of Engineering College Qufu Normal UniversityRizhao 276826ShandongChina

For a type of high⁃order discrete⁃time nonlinear systems(HDNS)whose system models are undefined,a model⁃free predictive control(MFPC)algorithm is proposed in this *** first,an estimation model is given by the improved projection algorithm to approach the controlled nonlinear ***,on the basis of the estimation model,a predictive controller is designed by solving the finite time domain rolling optimization quadratic function,and the controller’s explicit analytic solution is also ***,the closed⁃loop system's stability can be ***,the results of simulation reveal that the presented control strategy has a faster convergence speed as well as more stable dynamic property compared with the model⁃free sliding mode control(MFSC).

关键词： nonlinear system compact dynamic linearization(CDL) model predictive control(MPC) model-free control(MFC) projection algorithm

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Study on segmented distribution for reliability evaluation

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Chinese Journal of Aeronautics 2017年第1期30卷 310-329页

作者： Li Huaiyuan Zuo Hongfu su Yan Xu juan Yin Yibing School of Software Engineering Jinling Institute of Technology College of Civil Aviation Nanjing University of Aeronautics and Astronautics

In practice, the failure rate of most equipment exhibits different tendencies at different stages and even its failure rate curve behaves a multimodal trace during its life cycle. As a result,traditionally evaluating the reliability of equipment with a single model may lead to severer ***, if lifetime is divided into several different intervals according to the characteristics of its failure rate, piecewise fitting can more accurately approximate the failure rate of equipment. Therefore, in this paper, failure rate is regarded as a piecewise function, and two kinds of segmented distribution are put forward to evaluate reliability. In order to estimate parameters in the segmented reliability function, Bayesian estimation and maximum likelihood estimation（MLE） of the segmented distribution are discussed in this paper. Since traditional information criterion is not suitable for the segmented distribution, an improved information criterion is proposed to test and evaluate the segmented reliability model in this paper. After a great deal of testing and verification,the segmented reliability model and its estimation methods presented in this paper are proven more efficient and accurate than the traditional non-segmented single model, especially when the change of the failure rate is time-phased or multimodal. The significant performance of the segmented reliability model in evaluating reliability of proximity sensors of leading-edge flap in civil aircraft indicates that the segmented distribution and its estimation method in this paper could be useful and accurate.

关键词： Bayesian estimates Gibbs sampling method Maximum likelihood estima-tion Proximity sensors in leadingedge flap in aircraft Reliability Segmented distribution Weibull distribution

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A brief review on the diagnostic and therapeutic principles of primary urethral cancer

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Asian Journal of Urology 2022年第4期9卷 423-429页

作者： Hengchuan su Yao Zhu Dingwei ye Department of Urology Fudan University Shanghai Cancer CenterShanghaiChina Department of Oncology Shanghai Medical CollegeFudanUniversityShanghaiChina

Objective:Primary urethral carcinoma(PUC)is a rare malignant carcinoma but with limited therapeutic *** review aims to provide an overview of the current strategies on this patient ***:Recent literature ranging from January 1987 and December 2021 was assessed through PubMed search to assess the diagnostic and therapeutic principles of ***:A complete of examination including cystoscopy,imaging,and biopsy should be conducted for these *** diagnosed,the clinical decision of PUC should be made according to the tumor location,pathological pattern,and extent of the *** patients with superficial and distal urethral lesions,organ sparing approaches or radical reconstructive procedures can be *** for more advanced disease or nodal involvement,an optimal multimodal treatment strategy consisted of surgery and radiochemotherapy should be *** patients with urothelial carcinoma of the prostate,the management including transurethral resection of the prostate followed by bacille Calmette-Guerin or radical cysto-prostatectomy should depend on the infiltration depth of ***:A complete of examination is important for the diagnosis of *** management of PUC should be determined by the location,pathological pattern,and extent of the *** multi-institutional collaborations should be held to investigate better treatment modal-ities for PUC.

关键词： Diagnosis Management Primary Urethral Cancer

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Friction and wear behavior of Mg–11Y–5Gd–2Zn–0.5Zr(wt%)alloy with oil lubricant

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Rare Metals 2013年第5期32卷 453-458页

作者： Li-Jie Cao Qu-Dong Wang Yu-juan Wu Bing ye College of Mechanical Engineering Shanghai University of Engineering Science National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong University

The sliding friction and wear behaviors of Mg-11Y-5Gd-2Zn-0.5Zr （wt%） alloy were investigated under oil lubricant condition by pin-on-disk configuration with a constant sliding distance of 1,000 m in the temperature range of 25-200℃. Results indicate that the volumetric wear rates and average friction coefficients decrease with the increase of sliding speeds, and increase with the increase of test temperature below 150℃. The hard and thermally stable Mg12（Y,Gd）Zn phase with long-period stacking order structure in the alloy presents significant wear resistance, The wear mechanism below 100℃ is abrasive wear as a result of plastic extrusion deformation. The corporate effects of severe abrasive, oxidative, and delaminating wear result in the tribological mechanism above 100℃.

关键词： Mg-11Y-5Gd-2Zn-0.5Zr alloy Long-period stacking order (LPSO) structure Lubricated Friction and wear

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Application of Enzymatic Promiscuity in Pharmaceutical Synthesis:Papain-catalyzed One-pot Synthesis of 1,4-Dihydropyridine Calcium Channel Antagonists and Derivatives

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Chemical Research in Chinese Universities 2019年第1期35卷 21-25页

作者： JIANG Ling ye Wenting su Weike YU Chuanming Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of TechnologyHangzhou 310014P.R.China Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education College of Pharmaceutical Sciences Zhejiang University of Technology Hangzhou 310014P.R.China

A new method for the synthesis of 1,4-dihydropyridine(1,4-DHP)calcium channel antagonists felodipme, nitrendipine and their derivatives via papain-catalyzed three-component reactions of aldehyde,methyl acetoacetate and ethyl 3-aminocrotonate was *** simplicity,mild reaction conditions and eco-friendliness are the key features of this protocol.

关键词： Papain Catalytic promiscuity Multicomponent reaction 1,4-Dihydropyridine calcium channel antagonist

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Artificial intelligence and deep learning in ophthalmology:Current status and future perspectives

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Advances in Ophthalmology Practice and Research 2022年第3期2卷 47-53页

作者： Kai Jin juan ye Department of Ophthalmology The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina

Background:The ophthalmology field was among the first to adopt artificial intelligence(AI)in *** availability of digitized ocular images and substantial data have made deep learning(DL)a popular *** text:At the moment,AI in ophthalmology is mostly used to improve disease diagnosis and assist decisionmaking aiming at ophthalmic diseases like diabetic retinopathy(DR),glaucoma,age-related macular degeneration(AMD),cataract and other anterior segment ***,most of the AI systems developed to date are still in the experimental stages,with only a few having achieved clinical *** are a number of reasons for this phenomenon,including security,privacy,poor pervasiveness,trust and explainability ***:This review summarizes AI applications in ophthalmology,highlighting significant clinical considerations for adopting AI techniques and discussing the potential challenges and future directions.

关键词： Artificial intelligence Deep learning Ophthalmology Diabetic retinopathy Glaucoma Age-related macular degeneration

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Observation of two-times self-focusing of femtosecond laser beam in ZnO crystal by two-photon luminescence

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Science Bulletin 2018年第21期63卷 1392-1396页

作者： Xiaorui Wang Honggang ye Zhicheng su Dapeng Yu Shijie Xu Department of Physics and Shenzhen Institute of Research and Innovation (HKU-SIRI)The University of Hong KongHong KongChina Department of Physics Southern University of Science and TechnologyShenzhen 518055China Department of Applied Physics Xi'an Jiaotong UniversityXi'an 710049China

By ‘‘seeing" the green two-photon luminescence, two separate focusing points are observed on the propagation axis of a converging femtosecond laser beam in a ZnO single crystal rod. It is found that the selffocusing effect makes a significant contribution to the formation of the first focusing point, while the second focusing point is caused by self-refocusing. The position of the first focusing point is in good agreement with the value predicted by a model developed by Chin and his co-workers. These experimental findings could be the unprecedented evidence for the self-focusing and refocusing effect of the femtosecond laser filament propagation in nonlinear media.

关键词： Self-focusing Self-refocusing ZnO rod Two-photon luminescence

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