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Numerical Analysis of Three-Layer Deep Tunnel Composite Structure

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Computer Modeling in Engineering & Sciences 2021年第4期127卷 223-239页

作者： Weiwei Sun Hongping Min Jianzhong Chen chao ruan Yanjun Zhang Lei Wang Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan430070China China Construction Third Bureau Green Industry Investment Co. Ltd.Wuhan430035China Fujian Lutong Pipe Technology Co. Ltd.Quanzhou362000China

To date,with the increasing attention of countries to urban drainage system,more and more regions around the world have begun to build water conveyance tunnels,sewage pressure deep tunnels and so ***,the sufficient bearing capacity and corrosion resistance of the structure,which can ensure the actual service life and safety of the tunnel,remain to be further *** Fiber Reinforced Plastics(GFRP)pipe,with light weight,high strength and corrosion resistance,has the potential to be applied to the deep tunnel *** paper proposed a new composite structure of deep tunnel lined with GFRP pipe,which consisted of three layers of concrete segment,cement paste and GFRP pipe.A new pipe-soil spring element model was proposed for the pipesoil interaction with *** on the C3D8R solid model and the Combin39 spring model,the finite element numerical analysis of the internal pressure status and external pressure stability of the structure was carried *** with the checking calculation of the theoretical formula,the reliability of the two finite element models was confirmed.A set of numerical analysis methods for the design and optimization of the three-layer structure was *** results showed that from the internal GFRP pipe to the outer concrete pipe,the pressure decreased from 0.5 to 0.32 MPa,due to the internal pressure was mainly undertaken by the inner GFRP *** allowable buckling pressure of GFRP pipe under the cover of 5 GPa high modulus cement paste was 2.66 *** application of GFRP pipe not only improves the overall performance of the deep tunnel structure but also improves the construction quality and *** three-layer structure built in this work is safe and economical.

关键词： GFRP pipe deep tunnel structure finite element analysis internal pressure external pressure stability pipe-soil interaction

Detection of scab in wheat ears using in situ hyperspectral data and support vector machine optimized by genetic algorithm

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International Journal of Agricultural and Biological Engineering 2020年第2期13卷 182-188页

作者： Linsheng Huang Hansu Zhang chao ruan Wenjiang Huang Tingguang Hu Jinling Zhao National Engineering Research Center for Agro-Ecological Big Data Analysis&Application Anhui UniversityHefeiChina Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina

A new method was proposed to extract sensitive features and to construct a monitoring model for wheat scab based on in situ hyperspectral data of wheat ears to achieve effective prevention and control and provide theoretical support for its large-scale *** sensitive features were selected through correlation analysis and wavelet *** features were as follows:three original bands of 350-400 nm,500-600 nm,and 720-1000 nm;three vegetation indices of modified simple ratio(MSR),normalized difference vegetation index,and structural independent pigment index;and two wavelet features of WF01 and *** combining the selected sensitive features with support vector machine(SVM)and SVM optimized by genetic algorithm(GASVM),a total of 16 monitoring models were built,and the monitoring accuracies of the two types of models were *** ability of the monitoring models built by GASVM to identify scab was better than that of SVM algorithm under the same characteristic *** the 16 models,MSR combined with GASVM had an overall accuracy of 75%and a Kappa coefficient of *** can be used to monitor wheat scab and its application can improve the accuracy of disease monitoring.

关键词： wheat scab hyperspectral data correlation analysis genetic algorithm wavelet transform support vector machine

Contrast sensitivity in 14 MeV fast neutron radiography

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Nuclear Science and Techniques 2017年第6期28卷 115-122页

作者： Chang-Bing Lu Jie Bao Ying Huang Peng Xu Xiong-Jun Chen Qi-Wei Zhang Xi-chao ruan Key Laboratory of Nuclear Data China Institute of Atomic Energy Xi'an Institute of High Technology Science and Technology Information Center China Academy of Engineering Physics

Fast neutron radiography(FNR) is an effective non-destructive testing *** to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be *** order to obtain the minimum detectable thickness by FNR,we studied the contrast sensitivity of FNR lead samples,both theoretically and *** then clarified the relationship between pixel value and irradiation time,and sample materials and *** experiment,using a4-cm-thick lead sample,verified our theoretical expression of FNR contrast sensitivity.

关键词： Fast neutron radiography Contrast sensitivity Experimental research

A new spectral index for the quantitative identification of yellow rust using fungal spore information

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Big Earth Data 2021年第2期5卷 201-216页

作者： Yu Ren Huichun Ye Wenjiang Huang Huiqin Ma Anting Guo chao ruan Linyi Liu Binxiang Qian Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Hainan Key Laboratory of Earth Observation Hainan Institute of Aerospace InformationChinese Academy of SciencesSanyaChina

Yellow rust(Puccinia striiformis ***)is a frequently occurring fungal disease of winter wheat(Triticum aestivum L.).During yellow rust infestation,fungal spores appear on the surface of the leaves as yellow and narrow stripes parallel to the leaf *** analyzed the effect of the fungal spores on the spectra of the diseased leaves to find a band sensitive to yellow rust and established a new vegetation index called the yellow rust spore index(YRSI).The estimation accuracy and stability were evaluated using two years of leaf spectral data,and the results were compared with eight indices commonly used for yellow rust *** results showed that the use of the YRSI ranked first for estimating the disease ratio for the 2017 spectral data(R^(2)=0.710,RMSE=0.097)and outperformed the published indices(R^(2)=0.587,RMSE=0.120)for the validation using the 2002 spectral *** random forest(RF),k-nearest neighbor(KNN),and support vector machine(SVM)algorithms were used to test the discrimination ability of the YRSI and the eight commonly used indices using a mixed dataset of yellow-rust-infested,healthy,and aphid–infested wheat spectral *** YRSI provided the best performance.

关键词： Yellow rust spectral index fungal spores quantitative identification hyperspectral remote sensing winter wheat

Measurement and simulation of the leakage neutron spectra from Fe spheres bombarded with 14 MeV neutrons

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Nuclear Science and Techniques 2023年第12期34卷 17-29页

作者： Qi Zhao Yang‑Bo Nie Yan‑Yan Ding Shi‑Yu Zhang Jie Ren Kuo‑Zhi Xu Xin‑Yi Pan Xi‑chao ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Iron is commonly used as a structural and shielding material in nuclear devices. The accuracy of its nuclear data is critical for the design of nuclear devices. The evaluation data of ^(56)Fe isotopes in the latest version of the CENDL-3.2 library from China was significantly updated. This new data must be tested before it can be used. To test the reliability of this data and assess the shielding effect, a shielding benchmark experiment was conducted with natural Fe spherical samples using a pulsed deuterium–tritium neutron source at the China Institute of Atomic Energy(CIAE). The leakage neutron spectra from the natural spherical iron samples with different thicknesses(4.5, 7.5, and 12 cm) were measured between 0.8 and 16 MeV after interacting with 14 MeV neutrons using the time-of-flight method. The simulation results were obtained by Monte Carlo simulations by employing the Fe data from the CENDL-3.2, ENDF/B-VIII.0, and JEDNL-5.0 libraries. The measured and simulated leakage neutron spectra and penetration rates were compared, demonstrating that the CENDL-3.2 library performs sufficiently overall. The simulation results of the other two libraries were underestimated for scattering at the continuum energy level.

关键词： Iron sphere CENDL-3.2 Shielding benchmark experiment Pulsed 14 MeV neutron source Time-of-flight method

Involvement of Angiotensin II Type 1 Receptor and Calcium Channel in Vascular Remodeling and Endothelial Dysfunction in Rats with Pressure Overload

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Current Medical Science 2020年第2期40卷 320-326页

作者： Dong-rui CHEN Hui JIANG- Jing CHEN Cheng-chao ruan Wei-qing HAN Ping-jin GAO State Key Laboratory of Medical Genomics Shanghai Key Laboratory of HypertensionRiuijin HospitalShanghai Jiao Tong Universitry School of MedicineShanghai 200025China Shanghai Institule of Hypertension Shanghai 200025China

Vascular remodeling is an adaptive response to various stimuli,including mechanical forces,inflammatory cy tokines and *** the present study,we investigated the role of angiotensinII type 1 receptor(ATIR)and calcium channel in carotid artery remodeling in response to increased biomechanical forces by using the transverse aortic constriction(TAC)rat *** was induced on ten week-old male Sprague Dawley rats and these models were treated with ATIR blocker olmesartan(1 mg/kg/day)or/and calcium channel blocker(CCB)amlodipine(0.5 mgkgday)for 14 *** the treatment,the right common carotid artery proximal to the band(RCCA-B)was collected for further *** showed that olmesartan,but not amlodipine,significantly prevented TAC-induced adventitial ***,olmesartan,but not amlodipine,significantly prevented vascular inflammation,as indicated by increased tumor necrosis factor a(TNF-a)and increased p65 phosphorylation,an indicator of nuclear factor K-light-chain-enhancer of activated B cells(NFkB)activation in *** contrast,both olmesartan and amlodipine reversed the decreased expression of endothelial nitric oxidase synthase(eNOS)and improved endothelium-dependent vasodilation,whereas combination of olmesartan and amlodipine showed no further synergistic protective *** results suggest that AT1R was involved in vascular remodeling and inflammation in response to pressure overload,whereas ATIR and subsequent calcium channel were involved in endothelial dysfunction.

关键词： transverse aortic constriction angiotensin II type I receptor calcium channel vascular remodcling endothelial dysfunction

Benchmarking of JEFF-3.2, FENDL-3.0 and TENDL-2014 evaluated data for tungsten with 14.8 MeV neutrons

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Nuclear Science and Techniques 2017年第3期28卷 1-6页

作者： Suyalatu Zhang Yang-Bo Nie Jie Ren Fei Luo Xi-chao ruan Zhi-Qiang Chen Rui Han Temuerbagen Bao Si-Miao Ge College of Physics and Electronics Information Inner Mongolia University for the Nationalities China Nuclear Data Center China Institute of Atomic Energy Institute of Modern Physics Chinese Academy of Sciences School of Chemical Engineering Sichuan University

Integral experiments on tungsten slab samples were carried out on the D-T neutron source facility at China Institute of Atomic Energy. Leakage neutron spectra from the irradiated tungsten target were measured by the time-of-flight technique. Accuracy of the nuclear data for tungsten was examined by comparing the measured neutron spectra with the leakage neutron spectra simulated using the MCNP-4C code with evaluated nuclear data of the JEFF-3.2, FENDL-3.0 and TENDL-2014 libraries. The results show that the calculations with JEFF-3.2 agree well with the measurements in the whole energy range and all angles, whereas the spectra calculated with FENDL-3.0 and TENDL-2014 have some discrepancies with the experimental data.

关键词： Integral experiment D-T neutron source Time-of-flight technique Leakage neutron spectrum Monte Carlo simulation Evaluated nuclear data

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电弧放电法制备碳纳米管研究进展

材料导报 2020年第11期34卷 11129-11136页

作者：阮超陈名海江西铜业技术研究院有限公司

碳纳米管作为一种一维纳米材料具有独一无二的力学、光学、电子、热稳定及化学稳定特性,主要被应用于锂离子电池电极材料、金属、树脂、塑料、橡胶的改性增强领域。但碳纳米管也存在缺点,尤其是其合成结构的不可控性,严重阻碍了它的进... 详细信息

碳纳米管作为一种一维纳米材料具有独一无二的力学、光学、电子、热稳定及化学稳定特性,主要被应用于锂离子电池电极材料、金属、树脂、塑料、橡胶的改性增强领域。但碳纳米管也存在缺点,尤其是其合成结构的不可控性,严重阻碍了它的进一步应用。因此,探索出制备高品质大规模碳纳米管的生产技术迫在眉睫。目前,碳纳米管常用的合成方法有化学气相沉积、电弧放电和激光烧蚀,相比于其他两种方法,电弧放电法更为经济、高效。采用电弧法合成的碳纳米管纯度高达90%,石墨化程度远胜化学气相沉积法。同时,单次电弧实验时间在1～30 min之间,电源输出功率在750～3 000 W之间,且单次碳纳米管产量高达15 g,复合石墨电极的转化率高于75%。根据引弧介质的不同,电弧法可分为真空电弧放电与溶液电弧放电。溶液中碳纳米管的产量很低,因此溶液电弧放电法未得到推广;目前真空介质的研究则非常成熟,真空电弧放电法具有合成设备简单、操作便捷、产物品质高等优势,但其生长机理存在较大争议。电弧法的影响参数主要包括电源类型、引弧气体类型与压力以及催化剂体系。其中,最为成熟的工艺是采用直流电源、氦气引弧、钇镍两相催化进行放电实验。本文归纳了电弧放电法制备碳纳米管的研究进展,分别介绍了电弧放电法生长碳纳米管的装置构造与反应机理、对电弧放电法产生影响的参数,分析了电弧放电法合成碳纳米管面临的难题以及可改善空间,以期为制备高品质、高石墨化程度、规模化的碳纳米管提供借鉴。

关键词：电弧放电碳纳米管电源气氛气压催化剂

Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-chao ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data