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Angular Tolerance Enhancement in Guided-Mode Resonance Filters with a Photonic Crystal Slab

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Chinese Physics Letters 2012年第3期29卷 91-93页

作者： LI Cheng-Guo GAO Yong-Hao xu Xing-sheng State Key Laboratory of Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

Two different triple-layer guided-mode resonance(GMR)filters with photonic crystal(PC)slab structures are designed,and their main optical properties are *** is shown that under normal incidence,the PC slab GMR filters exhibit narrower bandwidth,a more symmetric line shape,and larger angular tolerance,compared with the planar grating GMR *** rod-slab type GMR filter works better than the hole-slab *** resonance wavelength location and the angular tolerance can be tuned by varying the *** angular tolerance with narrow bandwidth can be improved by increasing the ratio of the periods in the two crossed directions.

关键词： filters Crystal narrow

Lattice Boltzmann Simulation of Convection in a Porous Medium with Temperature Jump and Velocity Slip Boundary Conditions

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Communications in Theoretical Physics 2008年第5期49卷 1319-1322页

作者： xu You-sheng LIU Yang YANG Xiao-Feng WU Feng-Min Department of Physics Zhejiang Normal University Jinhua 321004 China Department of Mechanically Engineering The Hong Kong Polytechnic University Kowloon Hong Kong China Department of Computer Engineering Yiwu Industrial and Commercial College Yiwu 322000 China

To investigate the convection in a porous medium, a horizontal quiescent layer of one fluid saturating a porous medium heated from bottom is numerically studied using single lattice-Boltzmann method （LBM） and the generalized Navier Stokes equation proposed by Nithiarasu et al. [P. Nithiarasu, K.M. Seetharamu, and T Sundararajan Int. J. Heat Mass Trans. 40 （1997） 3955]. Due to the rarefaction, the boundary conditions are considered as both temperature jump and velocity slip. The computational results are vahdated against the analytical results, and excellent agreement has been obtained. The results have shown that the Rayleigh number is increased with increasing temperature jump, the stabilization effect of temperature is much more significant than that of velocity slip, and the computation stability of present model is better than that of Darey and Brinkman models.

关键词： convection in porous medium lattice Boltzmann method boundary condition

Predicting the excavation damaged zone within brittle surrounding rock masses of deep underground caverns using a comprehensive approach integrating in situ measurements and numerical analysis

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Geoscience Frontiers 2022年第2期13卷 186-199页

作者： Ding-Ping xu Xiang Huang Shao-Jun Li Huai-sheng xu Shi-Li Qiu Hong Zheng Quan Jiang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

Excavation Damaged Zone(EDZ)scope is important for optimizing excavation and support schemes in deep underground ***,accurately predicting the full EDZ scope within the surrounding rock masses of deep underground caverns during excavation remains a pressing *** study presents a comprehensive EDZ scope prediction approach(CESPA)for the brittle surrounding rock masses of deep underground caverns by coupling numerical simulation with quantitative analysis of borehole wall images and ultrasonic test ***,the changes in both P-velocity(V_(p))and joint distribution of the surrounding rock masses before and after excavation damage are captured using ultrasonic tests and borehole digital ***,the quality Q-parameters of the surrounding rock mass before and after excavation damage are preliminarily rated with the rock mass descriptions provided by borehole wall images,and the rock mass V_(p)-parameter values are determined according to the V_(p)-borehole depth ***,the Q-parameter ratings are further finely adjusted by updating the related Q-values to be similar with the Q-values estimated by V_(p)-parameter ***,the initial and residual mechanical parameters for the rock mass deterioration model(RDM)are estimated by the adjusted Q-parameter ratings based on the modified Q-based relations,and the elastic modulus deterioration index(EDI)threshold to describe the EDZ boundary is determined with the V_(p)-parameter ***,EDZ scope is predicted using the elastoplastic numerical simulation with RDM and EDI based on the mechanical parameter estimates and EDI *** of applications in Sub-lab D1 in Jinping II project show that CESPA can provide a reliable and operable solution for predicting full EDZ scopes within the brittle surrounding rock masses of deep underground caverns.

关键词： Excavation damaged zone Borehole digital camera Ultrasonic test Q-system Rock mass deterioration model

Ultraslow-light effects in symmetric and asymmetric waveguide structures with moon-like scatterers

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Frontiers of physics 2017年第1期12卷 117-121页

作者： Yong Wan Xiao-Hui Ge sheng xu Yue Guo Feng Yuan College of Physics Science Qingdao University Qingdao 266071 China

Ultraslow-light effects in two-dimensional hexagonal-lattice coupled waveguide with moon-like scat- terers were theoretically studied using the plane-wave expansion method. For symmetric structures, simulations showed that slow light with high group index can be achieved by shifting the scatterers and adjusting the radius of moon-like scatterers. The maximum group index was over 8.0 × 10^4. For asymmetric structures, simulations showed that slow light with flat band and high group index can be obtained by shifting the scatterers, adjusting the radius of moon-like scatterers, and rotating the scatterers. The maximum group index was over 5.7 ×10^5 with a ＂saddle-like＂ relationship between the frequency and group index.

关键词： moon-like scatterer slow light coupled waveguide photonic crystal

Haploinsufficiency of A20 (HA20): updates on the genetics, phenotype, pathogenesis and treatment

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World Journal of Pediatrics 2020年第6期16卷 575-584页

作者： Mei-Ping Yu Xi-sheng xu Qing Zhou Natalie Deuitch Mei-Ping Lu Department of Rheumatology Immunology and Allergy.Children's Hospital Zhejiang University School of MedicineHangzhou 310052China MOE Key Laboratory of Biosystems Homeostasis&Protection Life Sciences Institute.Zhejiang UniversityHangzhouChina Genetics Department Stanford UniversityCaliforniaUSA

Background A20,a protein encoded by the tumor necrosis factor alpha-induced protein 3 gene(TNFAIP3),plays a vital role in the negative regulation of inflammation and ***-of-function mutation in TNFAIP3 leads to a new described autoinflammatory disease-haploinsufficiency of A20(HA20).Since HA20 was first described in 2016,a number of new cases have been described in this literature,however,the disease and its pathogenesis are poorly *** review seeks to improve clinical recognition of this disorder,and promote both earlier diagnosis and initiation of targeted therapies to improve patients’*** We reviewed 26 papers about A20 and HA20,and we summarized genetic variants and clinical manifestations of a total of 61 reported patients from 26 families identified to have a genetic diagnosis of germline pathogenic variants in TNFAIP3/***,we discussed the pathogenesis and treatment of *** A total of 24 pathogenic variants of A20 had been *** was significant clinical heterogeneity,even among those with the same variants in *** to receiving a molecular diagnosis of HA20,patients had been diagnosed with Behcet's disease,rheumatoid arthritis,rheumatic fever,juvenile idiopathic arthritis,systemic lupus erythematosus,and even adult-onset Stills'*** patients with HA20 that presented with inflammatory signatures in NF-kB signaling were mostly responsive to *** HA20 is a monogenic autoinflammatory disease with highly variable clinical *** extensive heterogeneity makes it difficult to set a clinical diagnostic criteria,and genetic sequencing is necessary for a definitive diagnosis of HA20.

关键词： Autoinflammatory disease HA20 NF-κB signaling TNFAIP3 Treatment

Photoluminescence properties of blue and green multiple InGaN/GaN quantum wells

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Chinese Physics B 2019年第10期28卷 541-545页

作者： Chang-Fu Li Kai-Ju Shi Ming-sheng xu Xian-Gang xu Zi-Wu Ji School of Microelectronics Shandong UniversityJinan 250100China School of Physics and Electronic Engineering Taishan UniversityTaian 271000China Key Laboratory of Functional Crystal Materials and Devices(Ministry of Education) Shandong UniversityJinan 250100China

The photoluminescence(PL) properties of blue multiple InGaN/GaN quantum well(BMQW) and green multiple InGaN/GaN quantum well(GMQW) formed on a single sapphire substrate are investigated. The results indicate that the peak energy of GMQW-related emission(PG) exhibits more significant "S-shaped" dependence on temperature than that of BMQW-related emission(PB), and the excitation power-dependent carrier-scattering effect is observed only in the PG emission;the excitation power-dependent total blue-shift(narrowing) of peak position(line-width) for the PGemission is more significant than that for the PBemission;the GMQW shows a lower internal quantum efficiency than the BMQW. All of these results can be attributed to the fact that the GMQW has higher indium content than the BMQW due to its lower growth temperature and late growth, and the higher indium content in the GMQW induces a more significant compositional fluctuation, a stronger quantum confined Stark effect, and more non-radiative centers.

关键词： photoluminescence multiple quantum wells localization effect light-emitting diodes

Generating colorful carrot germplasm through metabolic engineering of betalains pigments

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Horticulture Research 2023年第4期10卷 63-70页

作者： Yuan-Jie Deng Ao-Qi Duan Hui Liu Ya-Hui Wang Rong-Rong Zhang Zhi-sheng xu Ai-sheng Xiong National Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural University1 WeigangNanjing 210095China

Betalains are tyrosine-derived plant pigments exclusively found in the Caryophyllales order and some higher fungi and generally classified into two groups:red-violet betacyanins and yellow-orange *** attract great scientific and economic interest because of their relatively simple biosynthesis pathway,attractive colors and health-promoting ***-expressing two core genes BvCYP76AD1 and BvDODA1 with or without a glycosyltransferase gene MjcDOPA5GT allowed the engineering of carrot(an important taproot vegetable)to produce a palette of unique *** highest total betalains content,943.2μg·g^(−1) DW,was obtained in carrot taproot transformed with p35S:RUBY which produces all of the necessary enzymes for betalains ***-specific production of betalains slightly relieved tyrosine consumption revealing the possible bottleneck in betalains ***,a unique volcano-like phenotype in carrot taproot cross-section was created by vascular cambium-specific production of *** betalains-fortified carrot in this study is thus anticipated to be used as functional vegetable and colorful carrot germplasm in breeding to promote health.

关键词： germplasm breeding orange

Design,synthesis and insecticidal activity of spiro heterocycle containing neonicotinoid analogs

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Chinese Chemical Letters 2014年第2期25卷 197-200页

作者： Nan-Yang Chen Li-Ping Ren Min-Ming Zou Zhi-Ping xu xu-sheng Shao Xiao-Yong xu Zhong Li Shanghai Key Laboratory of Chemical Biology School of PharmacyEast China University of Science and Technology

Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenone framework were designed and synthesized. Insecticidal evaluation showed that some of spirobenzofuranone containing neonicotinoids exhibited moderate activity against cowpea aphid, armyworm or brown planthopper.

关键词： Neonicotinoid Spiro heterocycle Activity Insecticide

Two new steroidal glucosides from Ophiopogon japonicus (L.f.) Ker-Gawl

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Chinese Chemical Letters 2008年第7期19卷 825-828页

作者： Ya Jiuan xu Tun Hai xu Ling Zhu Hao Hong Feng Zhao sheng xu Xie Yun Shan Si Dong Han Dong Ming xu Academy of Traditional Chinese Medicine and Material Medica of Jilin Province Changchun 130021China School of Traditional Chinese Medicine Beijing University of Chinese Medicine Beijing 100102China School of Traditional Chinese Medicine Xinjiang University of Medicine Urumchi 830011 China

Two new steroidal glucosides, 26-O-β-D-glucopyranosyl （25S）-furost-5-ene-1β,3β,22α,26-tetraol l-O-β-D-xylopyranosyl- （1 → 3）-[α-h-rhamnopyranosyl-（1 → 2）]-[β-D-fueopyranoside and （25R） spirost-5-ene-3β,14α-diol-3-β-O-β-L-rhanmopyranosyl- （1 → 2）-[β-D-xylopyranosyl（1 → 4）]-[-β-D-glucopyranoside, were isolated from the Ophiopogon japonicus （L.f.） Ker-Gaw. Their structures were elucidated by spectroscopic methods.

关键词： Ophiopogon japonicus (L.f.) Ker-Gawl Steroidal glucosides Liliaceae