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薄直中隔墙连拱隧道钢带加固措施抗震效果

交通运输工程学报 2024年第3期24卷 124-138页

作者：王明年李泽星唐浪洲于丽路明西南交通大学土木工程学院四川成都610031 西南交通大学交通隧道工程教育部重点实验室四川成都610031

以宁巧隧道工程为研究对象,基于地震易损性分析方法,在FLAC3D中建立了三维动力时程数值计算模型;通过Python语言进行二次开发,实现了易损性分析中增量动力分析方法的全流程自动化计算;给出了薄直中隔墙连拱隧道结构在有无钢带加固措施、... 详细信息

以宁巧隧道工程为研究对象,基于地震易损性分析方法,在FLAC3D中建立了三维动力时程数值计算模型;通过Python语言进行二次开发,实现了易损性分析中增量动力分析方法的全流程自动化计算;给出了薄直中隔墙连拱隧道结构在有无钢带加固措施、2种地震波入射方向(水平与竖直方向)、2种围岩级别(Ⅳ与Ⅴ级)共8种不同因素组合下的易损性曲线,得到了结构在隧址区抗震设防烈度下的损伤概率;通过对比分析损伤概率评价了钢带加固措施的抗震效果及规律;通过大型振动台试验,对比相似模型结构在有无抗震措施下的破坏形态和损伤程度,验证了钢带加固措施的实际作用效果。研究结果表明:无论何种因素组合,钢带加固措施均能有效减小结构在不同损伤状态下的损伤概率,作用效果受围岩级别影响较大,受地震波入射方向影响较小;Ⅴ级围岩条件下,其轻微、中度、重度损伤状态下的损伤概率在地震波水平方向入射时分别减小了51.94%、41.29%、29.63%,在竖直方向入射时分别减小了55.68%、48.32%、35.29%;Ⅳ级围岩条件下,其轻微、中度、重度损伤状态下的损伤概率在地震波水平方向入射时分别减小了16.45%、11.19%、7.11%,在竖直方向入射时分别减小了12.23%、9.45%、7.49%;振动台试验中,使用钢带加固后的相似模型在最不利因素组合条件下的损伤程度明显低于无抗震措施结构;钢带加固措施能通过提高结构整体承载能力,有效地减少病害数量,降低结构损伤程度,提高结构抗震性能。

关键词：隧道工程连拱隧道抗震措施易损性分析振动台试验损伤概率钢带

鲜人参中丙二酰基人参皂苷-Ra_(1)、-Ra_(2)的分离及结构鉴定

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中国中药杂志 2024年第12期49卷 3252-3257页

作者：李泽文李丹李嘉星崔颖陆雅倩刘志吉林农业大学中药材学院吉林长春130118

该文旨在对鲜人参Panax ginseng根中的丙二酰基人参皂苷类化学成分进行研究。通过D101大孔吸附树脂柱、ODS柱色谱及高效液相色谱制备分离技术等方法,对鲜人参根中70%乙醇提取物的化学成分进行分离纯化,并通过高分辨质谱和核磁共振波谱... 详细信息

该文旨在对鲜人参Panax ginseng根中的丙二酰基人参皂苷类化学成分进行研究。通过D101大孔吸附树脂柱、ODS柱色谱及高效液相色谱制备分离技术等方法,对鲜人参根中70%乙醇提取物的化学成分进行分离纯化,并通过高分辨质谱和核磁共振波谱相结合的方法对化合物进行结构鉴定。从鲜人参提取物中分离得到2个丙二酰基人参皂苷,分别鉴定为3-O-[6-O-丙二酰基-β-D-吡喃葡萄糖基-(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃木糖基-(1→4)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-吡喃葡萄糖基]-达玛-24-烯-3β,12β,20S-三醇(1)和3-O-[6-O-丙二酰基-β-D-吡喃葡萄糖基-(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃木糖基-(1→2)-α-L-呋喃阿拉伯糖基-(1→6)-β-D-吡喃葡萄糖基]-达玛-24-烯-3β,12β,20S-三醇(2)。化合物1和2为首次从人参根中分离得到的新化合物,分别命名为丙二酰基人参皂苷-Ra_(1)(malonyl ginsenoside-Ra_(1))和丙二酰基人参皂苷-Ra_(2)(malonyl ginsenoside-Ra_(2))。

关键词：人参丙二酰基人参皂苷-Ra_(1) 丙二酰基人参皂苷-Ra_(2) 结构鉴定

Effects of microstructure on uniaxial strength asymmetry of open-cell foams

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Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 37-46页

作者： Zi-xing lu Ji-xiang HUANG ze-shuai YUAN Institute of Solid Mechanics Beihang University

Based on the elongated Kelvin model, the effect of microstructure on the uniaxial strength asymmetry of open-cell foams is investigated. The results indicate that this asymmetry depends on the relative density, the solid material, the cell morphology, and the strut geometry of open-cell foams. Even though the solid material has the same tensile and compressive strength, the tensile and compressive strength of open-cell foams with asymmetrical sectional struts are still different. In addition, with the increasing degree of anisotropy, the uniaxial strength as well as the strength asymmetry increases in the rise direction but reduces in the transverse direction. Moreover, the plastic collapse ratio between two directions is verified to depend mainly on the cell morphology. The predicted results are compared with Gibson and Ashby＇s theoretical results as well as the experimental data reported in the literature, which validates that the elongated Kelvin model is accurate in explaining the strength asymmetry presented in realistic open-cell foams.

关键词： open-cell foam microstructure strength Kelvin model

预涂覆膜重力流超滤工艺的过滤性能与滤饼层特性

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中国给水排水 2024年第13期40卷 21-27页

作者：王绍铸李星冯建勇孙亚洲路则栋北京工业大学城市建设学部北京100124

重力流超滤(GDM)具有操作简单、能耗低、维护少等特点,但稳定膜通量较低、生物滤饼层性能仍需改善。针对GDM生物滤饼层对稳定膜通量作用的关键问题,构建了铝基絮体(ABF)预涂覆GDM(ABF-GDM)工艺,研究了其过滤性能和滤饼层特性,阐明了ABF... 详细信息

重力流超滤(GDM)具有操作简单、能耗低、维护少等特点,但稳定膜通量较低、生物滤饼层性能仍需改善。针对GDM生物滤饼层对稳定膜通量作用的关键问题,构建了铝基絮体(ABF)预涂覆GDM(ABF-GDM)工艺,研究了其过滤性能和滤饼层特性,阐明了ABF预涂覆层对生物滤饼层特性的作用机制。ABF-GDM工艺的稳定膜通量为6.70 L/(m^(2)·h),比GDM提高了19.22%;滤饼层阻力和膜孔阻力分别为2.11×10^(12)m^(-1)和1.99×10^(11)m^(-1),比GDM降低了21.60%和19.37%;稳定阶段对溶解性有机碳和氨氮的平均去除率分别为22.10%和89.81%,比GDM提高了7.48%和5.92%。ABF预涂覆滤饼层可明显提高GDM生物滤饼层的粗糙度和多孔性,并降低胞外聚合物(EPS)含量,其中ABF-GDM的表面孔隙率达34.24%,比GDM高31.22%;EPS中蛋白质和多糖含量分别为723.40、1013.18 mg/m^(2),分别比GDM降低22.17%和31.92%。ABF预涂覆层可改变生物滤饼层的微生物群落结构,其中关键菌属的相对丰度变化可直接影响生物滤饼层的形貌结构和生化组分,使得ABF-GDM的滤饼层粗糙多孔性增加、EPS含量降低、稳定膜通量提高。

关键词：重力流超滤预涂覆膜铝基絮体稳定膜通量生物滤饼层

NνDEx-100 conceptual design report

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Nuclear Science and Techniques 2024年第1期35卷 18-33页

作者： Xi-Guang Cao Yan-Long Chang Kai Chen Emilio Ciuffoli Li-Min Duan Dong-Liang Fang Chao-Song Gao Surja K.Ghorui Peng-Chong Hu Qiang Hu Si-Yuan Huang ze-Yu Huang Lei Lang Yu-Lan Li Zhi-Jie Li Tian-Yu Liang Jun Liu Chen-Gui lu Fa-Tai Mai Yuan Mei Hao Qiu Xiang-Ming Sun Xiao-xing Tang Hu-Lin Wang Qian-Ming Wang Le Xiao Mu-Yun Xiao Jian-Yu Xin Nu Xu Peng Yang Yi-Chen Yang Zhen Yang Zong-Yang Yu Dong-Liang Zhang Jun-Wei Zhang Cheng-Xin Zhao Dou Zhu NνDEx-100 collaboration Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Lanzhou University Lanzhou 730000China Central China Normal University Wuhan 430079China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Lawrence Berkeley National Laboratory BerkeleyCA 94720USA North China University of Water Resources and Electric Power Zhengzhou 450045China 不详

Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle *** such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number *** propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx *** being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological *** makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββ***-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by *** report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation.

关键词： Neutrinoless double beta decay Time projection chamber ^(82)SeF_(6) China Jinping Underground Laboratory

Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analysis

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Chinese Journal of Polymer Science 2021年第2期39卷 219-227,I0007页

作者： ze-Qian Wang Zhen-xing Zhong Yu-Ying Ma Xiao-Feng lu Ce Wang Zhao-Hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Alan G.MacDiarmid Institute Jilin UniversityChangchun 130012China

Thermal properties such as melting temperature can well reflect the microstructure of the polymer material, and have practical implications in the application of nanofibers. In this work, we investigated the melting temperature of individual electrospun poly(vinylidene fluoride)(PVDF) nanofibers with diameters ranging from smaller than 200 nm to greater than 2 μm by the local thermal analysis technique. The PVDF fibers obtained under four different conditions were found to crystallize into α and β phases, and the fiber mats showed typical values in the crystallinity and Tm with no significant difference among the four. However, analyses at single fiber level revealed broad distribution in diameter and Tm for the fibers produced under identical electrospinning condition. The Tm of individual nanofibers was found to remain constant at large diameters and increase quickly when reducing the fiber diameter toward the nanoscale, and Tm values of 220-230 ℃ were observed for the thinnest nanofibers, much higher than the typical values reported for bulk PVDF. The Tm and molecular orientation at different positions along a beaded fiber were analyzed, showing a similar distribution pattern with a minimum at the bead center and higher values when moving toward both directions. The results indicate that molecular orientation is the driving mechanism for the observed correlation between the Tm and the diameter of the nanofibers.

关键词： Electrospun fibers PVDF Local thermal analysis Melting temperature

Photoselective green-light laser vaporisation vs. TURP for BPH. meta-analysis

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Asian Journal of Andrology 2012年第5期14卷 720-725页

作者： Hui Ding Wan Du ze-Ping lu Zhen-xing Zhai Han-Zhang Wang Zhi-Ping Wang Institute of Urology Key Laboratory of Urological Diseases in Gansu ProvinceGansu Nephro-Urological Clinical CenterThe Second Hospital of Lanzhou UniversityLanzhou 730000China Otolaryngological Department The Second Hospital of Lanzhou UniversityLanzhou 730000China The Medical College of Shandong University Jinan 250000China

This study sought to evaluate the efficacy and safety of photoselective vaporisation （PVP） vs. transurethral resection of the prostate （TURP） for patients with benign prostatic hyperplasia （BPH）. Eligible studies were identified from electronic databases （Cochrane Library, PubMed and EMBASE）. The database search, quality assessment and data extraction were performed independently by two reviewers. Efficacy （primary outcomes： maximum urinary flow rate （Qmax）, international prostate symptom score （IPSS）, postvoid residual urine （PVR） and quality of life （QoL）; secondary outcomes： operative time, hospital time and catheter removal time） and safety （complications, such as transfusion and capsular perforation） were explored by using Review Manager 5.0. Six randomized controlled trials （RCTs） and five case-controlled studies of 1398 patients met the inclusion criteria. A meta-analysis of the extractable data showed that there were no differences in I PSS, Qmax, QoL or PVR between PVP and TU RP （mean difference （MD）： prostate sizes 〈 70 ml, Qmax at 24 months, MD=0.01, P=0.97; IPSS at 12 months, MD=0.18, P=0.64; QoL at 12 months, MD=-0.00, P=0.96; PVR at 12 months, MD=0.52, P=0.43; prostate sizes 〉70 ml, Qmax at 6 months, MD=-3.46, P=0.33; IPSS at 6 months, MD=3.11, P=0o36; PVR at 6 months, MD=25.50,P=-0.39）. PVP was associated with a shorter hospital time and catheter removal time than TURP, whereas PVP resulted in a longer operative time than TURP. For prostate sizes 〈70 ml, there were fewer transfusions, capsular perforations, incidences of TUR syndrome and clot retentions following PVP compared with TURP. These results indicate that PVP is as effective and safe as TURP for BPH at the mid-term patient follow-up, in particular for prostate sizes 〈70 ml. Due to the different energy settings available for green-light laser sources and the higher efficiency and performance of higher-quality lasers, large-sample, long-term RCTs are required to verify whether different energy

关键词： benign prostatic hyperplasia (BPH) meta-analysis photoselective vaporisation transurethral resection of the prostate(TURP)

基因Ⅱ型草鱼呼肠孤病毒RAA-CRISPR/Cas12a检测方法的建立

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水生生物学报 2024年第11期48卷 1905-1914页

作者：肖思民侯泽玮刘方幸妍赵祎晨尹纪元徐伟吕利群王浩上海海洋大学国家水生动物病原库上海201306 上海海洋大学水产种质资源发掘与利用教育部重点实验室上海201306 中国水产科学研究院珠江水产研究所农业农村部渔药创制重点实验室广州510380

为建立一种特异性强、灵敏度高、操作便捷的Ⅱ型草鱼呼肠孤病毒(GCRV-Ⅱ)检测方法,研究利用重组酶介导链置换核酸扩增技术(Recombinase-aid amplification,RAA)与成簇的规律间隔短回文重复序列(CRISPR)系统相结合,构建了GCRV-Ⅱ病毒RAA... 详细信息

为建立一种特异性强、灵敏度高、操作便捷的Ⅱ型草鱼呼肠孤病毒(GCRV-Ⅱ)检测方法,研究利用重组酶介导链置换核酸扩增技术(Recombinase-aid amplification,RAA)与成簇的规律间隔短回文重复序列(CRISPR)系统相结合,构建了GCRV-Ⅱ病毒RAA结合CRISPR/Cas12a可视化“一步”快速检测方法。首先选择GCRV-Ⅱ毒株间序列保守,不同基因型GCRV间差异明显的s6基因(GQ896337)的保守区设计5对RAA候选引物和2对crRNA,合成并筛选出特异性引物和crRNA组合。其次测试反应的特异性、灵敏度和准确性。最后建立下层扩增相、上层检测相的“一步法”反应体系。该检测方法在37℃恒温下反应可检测出GCRV-Ⅱ,最低检测限为10^(2) copies/μL。对24份临床样本进行检测,该检测方法阳性检出率高于现行国标PCR法。研究建立的GCRV-Ⅱ检测方法操作便捷、特异性高、灵敏度好、可重复性强、与设备兼容性好、在蓝光灯下可通过肉眼判断检测结果。

关键词： GCRV-Ⅱ RAA CRISPR/Cas12a 现场诊断

Hsa_circ_0001658 accelerates the progression of colorectal cancer through miR-590-5p/METTL3 regulatory axis

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World Journal of Gastrointestinal Oncology 2023年第1期15卷 76-89页

作者： Yang lu xing-Ming Wang ze-Shu Li Ai-Juan Wu Wen-Xia Cheng Department of Oncology PKUCare Luzhong HospitalZibo 255400Shandong ProvinceChina Department of Oncology Zibo Maternal and Child Health HospitalZibo 255095Shandong ProvinceChina

BACKGROUND As reported,multiple circular RNAs(circRNAs)interfere with colorectal cancer(CRC)***,circRNA_0001658(circ_0001658)is focused on studying how it works in *** Clarify the expression pattern,biological function,and underlying mechanism of circ_0001658 of CRC *** In CRC-related chip data retrieved using the database named Gene Expression Omnibus,different expressions of circRNAs between CRC and normal tissue samples were *** Real-time PCR and Western blot ensured the analysis on circ_0001658,microRNA-590-5P(miR-590-5p),and methyltransferase-like 3(METTL3)mRNA expressions in tissues and *** counting kit-8 and flow cytometry were used to detect cell proliferation,apoptosis and *** targeting relations between circ_0001658,miR-590-5p,and METTL3 mRNA 3'-untranslated region were under the verification of bioinformatics prediction and dual luciferase-based reporter gene *** Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were employed on the downstream targets of miR-590-5p using the Database for Annotation,Visualization and Integrated Discovery *** Circ_0001658 and METTL3 mRNA was elevated in CRC tissues and cells,whereas miR-590-5p was ***_0001658 overexpression promoted the proliferation of HT29 cells,inhibited apoptosis,and accelerated the cell *** SW480 cells,knocking down circ_0001658 had the opposite ***_0001658 could specifically bind to miR-590-5p and negatively modulate its expressions;METTL3 is a miR-590-5p target that can be positively regulated by circ *** 0001658 was inversely associated with miR-590-5p expression while positively with METTL3 *** Circ_0001658 regulates the miR-590-5p/METTL 3-axis to increase CRC cell growth and decrease apoptosis.

关键词： Circ_0001658 miR-590-5p METTL3 Colorectal cancer Proliferation