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基于冻融循环试验的改良泥水盾构浆渣劣化特性研究

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现代隧道技术 2024年第1期61卷 260-271页

作者：张建勇中铁十四局集团大盾构工程有限公司南京211899

盾构隧道排放的渣土改性成路基材料可显著提高资源利用效率,但在反复冻融环境下存在安全隐患。依托武汉某盾构隧道工程,以大直径泥水盾构废弃浆渣为研究对象,通过添加自主研发的固废基胶凝剂(Cement-Slag-Gypsum-Alum,CSGA)及玄武岩纤维... 详细信息

盾构隧道排放的渣土改性成路基材料可显著提高资源利用效率,但在反复冻融环境下存在安全隐患。依托武汉某盾构隧道工程,以大直径泥水盾构废弃浆渣为研究对象,通过添加自主研发的固废基胶凝剂(Cement-Slag-Gypsum-Alum,CSGA)及玄武岩纤维(BF)对盾构浆渣进行改良,并对CSGA-BF改良后的盾构浆渣开展冻融循环试验,研究不同纤维掺量、冻融循环次数等条件对改良盾构浆渣的外观劣化特性、力学特性及微观损伤机制的影响。结果表明:在冻融循环作用下,改良浆渣体积呈波浪式变化,并且整体表现为体积膨胀;随着冻融循环次数增加,改良盾构浆渣的无侧限抗压强度及弹性模量均呈现非线性递减,适当掺量的玄武岩纤维可增强筋-土界面的摩擦力,对浆渣的抗冻性具有重要作用,但纤维过量添加也会造成试样强度降低;当冻融循环达到9次后,改良盾构浆渣的抗压强度及弹性模量趋于稳定并且孔隙之间呈现贯通趋势。

关键词：大直径泥水盾构冻融循环废弃浆渣劣化机制

2022—2023年四川泸定M_(S)6.8、M_(S)5.0和M_(S)5.6地震序列的发震构造及成因

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地球物理学报 2024年第4期67卷 1471-1486页

作者：张建勇王新陈凌刘杰中国地震台网中心北京100045 岩石圈演化国家重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院地球与行星物理重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049

四川泸定2022年9月5日发生M_(S)6.8强震,随后10月22日和2023年1月26日又分别发生M_(S)5.0和M_(S)5.6强余震,主震和两次强余震的震中相距仅几公里却有着截然不同的震源机制解,因此,探究三者的发震构造、联系及成因至关重要.本研究利用国... 详细信息

四川泸定2022年9月5日发生M_(S)6.8强震,随后10月22日和2023年1月26日又分别发生M_(S)5.0和M_(S)5.6强余震,主震和两次强余震的震中相距仅几公里却有着截然不同的震源机制解,因此,探究三者的发震构造、联系及成因至关重要.本研究利用国家地震台网记录到的这三次地震序列的连续波形数据及震相资料进行双差重定位,并进一步采取CAP波形反演方法和P波初动极性反演方法获得研究区M_(L)2.5+的79个余震震源机制解.结果显示,主破裂沿鲜水河断裂磨西段,破裂彻底,余震活动性不高.沿主断裂分布的余震具有明显的分段特征,断层近直立且西北浅东南深.主震及磨西段大部分余震均为走滑机制,是典型的印度—欧亚板块挤压旋转造成鲜水河走滑断裂带应力失稳触发的强震活动.发生在贡嘎山地区的余震是M_(S)6.8主震触发的震群活动,震级水平不高,分布弥散,并没有触发与主断裂共轭的燕子沟、海螺沟和磨子沟次级断裂,而是触发了与主断裂近平行的次级隐伏断裂——贡嘎山断裂.M_(S)5.0和M_(S)5.6两次强余震均发生在该次级隐伏断裂上,断层倾角40°~50°且震源深度较浅.贡嘎山地区拉张型地震活动明显不同于走滑型为主的鲜水河断裂带,可能是印度—欧亚板块挤压旋转作用下贡嘎山快速隆升而地表快速剥离导致局部因重力卸载而垮塌造成的,M_(S)6.8主震有明显的触发作用.三次泸定强震的发生,释放了磨西段及西侧贡嘎山地区部分应力,但并未改变"Y"字形交汇区强震发生的可能性.

关键词：四川泸定地震鲜水河断裂带贡嘎山地区发震构造地震活动性

Crustal structure study based on principal component analysis of receiver functions

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Science China Earth Sciences 2019年第7期62卷 1110-1124页

作者： jianyong zhang Ling CHEN Xu WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences

The receiver function(RF) technique is an effective method for studying crustal structure. For a single station, the average 1-D crustal structure is usually derived by stacking the radial RFs from all back-azimuths, whereas structural variations(such as dipping discontinuities or anisotropy) can be constrained through analysis of waveform dependence on the backazimuth of both the radial and tangential RFs. However, it is often difficult to directly extract information about structural variations from the waveform of RF, due to the common presence of noise in real data. In this study, we proposed a new method to derive structural variation information for individual stations by applying principal component analysis(PCA) to RFs sorted by back-azimuth. In this method(termed as RF-PCA), a set of principal components(PCs), which are uncorrelated with each other and reflect different characteristics of the RF data, were extracted and utilized separately to reconstruct new RFs. Synthetic tests show that the first PC of the radial RFs contains the average structural information of the crust beneath the corresponding station, and the second PC of the radial RFs and the first PC of the tangential RFs both reflect the variations of the crustal structure. Our synthetic modeling results indicate that the new RF-PCA method is valid for a variety of synthetic models with intra-crustal dipping discontinuities and/or anisotropy. We applied this method to the real data from a broadband temporary seismic station(s233) in the central part of the Sichuan Basin. The results suggest that the RF data can be best explained by the presence of two nearly parallel dipping discontinuities within the crust. Combining with previous logging data, seismic exploration and deep sounding observations, we interpret the shallow dipping discontinuity as the top boundary of the Precambrian crystalline basement of the Sichuan Basin and the deep one corresponding to the Conrad interface between the upper and lower crust, consistent with the geological f

关键词： Principal component analysis Receiver function Crustal structure Dipping discontinuity Anisotropy Sichuan Basin

From Zeolitic Imidazolate Framework-8 to Metal-Organic Frameworks (MOFs): Representative Substance for the General Study of Pioneering MOF Applications

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Energy & Environmental Materials 2018年第4期1卷 209-220页

作者： Dianting Zou Dingxin Liu jianyong zhang MOE Key Laboratory of Polymeric Composite and Functional Materials School of Materials Science and EngineeringSun Yat-Sen UniversityGuangzhou 510275China

Metal-organic frameworks(MOFs)have been intensely studied for the past few decades as an enormous family of highly tunable porous materials with promisingly applicable functionalities in adsorption,separation,catalysis,sensing,electrochemistry,and a great number of emerging purposes.As a classic MOF,zeolitic imidazolate framework-8(ZIF-8)is conventionally one of the very few MOF members that has been commercialized with considerable production.

关键词： metal-organic frameworks nanoporous composites zeolitic imidazolate frameworks zeolitic imidazolate framework-8

Effects of fuel combination and IVO timing on combustion and emissions of a dual-fuel HCCI combustion engine

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Frontiers in Energy 2020年第4期14卷 778-789页

作者： Xin LIANG jianyong zhang Zhongzhao LI Jiabo zhang Zhen HUANG Dong HAN Key Laboratory for Power Machinery and Engineering of the Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China

This paper experimentally and numerically studied the effects of fuel combination and intake valve opening(IVO)timing on combustion and emissions of an n-heptane and gasoline dual-flicl homogeneous charge compression ignition(HCCI)engine.By changing the gasoline fraction(GF)from 0」to 0.5 and the IVO timing from-15°CA ATDC to 35°CA ATDC,the in-cylinder pressure traces,heat release behaviors,and HC and CO emissions were investigated.The results showed that both the increased GF and the retarded IVO timing delay the combustion phasing,lengthen the combustion duration,and decrease the peak heat release rate and the maximum average combustion temperature,whereas the IVO timing has a more obvious influence on combustion than GF.HC and CO emissions are decreased with reduced GF,advanced IVO timing and increased operational load.

关键词： homogeneous charge compression ignition dual-fuel n-heptane gasoline intake valve opening timing

Extended pancreatoduodenectomy with portal vein and inferior vena cava resection and reconstruction combined with sorafenib for hepatoid carcinoma of the pancreas:a strategy of superextended surgery combined with targeted therapy

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Hepatobiliary Surgery and Nutrition 2023年第4期12卷 637-640,I0027-I0030页

作者： Deling Wei Banghao Xu Hai Zhu Jilong Wang Zongrui Jin Weitao Chen jianyong zhang Zhujing Lan Keyu Huang Ling zhang Tingting Lu Ni Fang Ya Guo Tao Peng Minhao Peng zhang Wen Department of Hepatobiliary Surgery the First Affiliated Hospital of Guangxi Medical UniversityNanningChina Department of Radiology the First Affiliated Hospital of Guangxi Medical UniversityNanningChina Department of Ultrasound the First Affiliated Hospital of Guangxi Medical UniversityNanningChina Department of Pathology the First Affiliated Hospital of Guangxi Medical UniversityNanningChina

Hepatoid carcinoma of the pancreas(HCP)is an extremely rare pancreatic cancer resembling hepatocellular carcinoma,a type of liver cancer(1).Most reports have shown that it has an aggressive behavior and is associated with early metastasis.There is no standardized treatment for HCP due to its rarity,and the limited number of cases reported in the literature(2,3).However,treatment options for this type of rare cancer include surgery,chemotherapy,and radiation therapy,depending on the stage of the cancer.Nevertheless,the prognosis of HCP is poor.

关键词： chemotherapy metastasis treatment

黄河流域生态保护与高质量发展耦合协调关系实证分析

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人民黄河 2024年第1期46卷 19-24页

作者：张杰张剑勇马蓝青海师范大学经济管理学院青海西宁810000 青海师范大学高原与可持续发展研究院青海西宁810000

为准确把握黄河流域生态保护与高质量发展的耦合协调关系,以黄河流域9个省(区)全域为研究对象,基于2016—2020年面板数据,采用熵值法、耦合协调模型对黄河流域生态保护与高质量发展的耦合协调关系进行了实证分析。结果表明:2016—2020... 详细信息

为准确把握黄河流域生态保护与高质量发展的耦合协调关系,以黄河流域9个省(区)全域为研究对象,基于2016—2020年面板数据,采用熵值法、耦合协调模型对黄河流域生态保护与高质量发展的耦合协调关系进行了实证分析。结果表明:2016—2020年黄河流域生态保护水平和高质量发展水平均呈上升态势,生态保护水平的区域格局由“下游高、中上游低”变为“中上游高、下游低”,高质量发展区域格局由“上中游高、下游低”变为“上中游低、下游高”;黄河流域生态保护与高质量发展耦合协调状况基本属于相互协调型,呈现由高质量发展相对滞后型向生态保护相对滞后型转变的趋势;研究期内,黄河流域生态保护与高质量发展耦合协调水平整体较低但呈稳步上升趋势,耦合协调等级大致经历了“轻度失调—濒临失调—勉强协调”的转变过程,今后还有较大提升空间。

关键词：生态保护高质量发展耦合协调实证分析黄河流域

Three-dimensional-printed collagen/chitosan/secretome derived from HUCMSCs scaffolds for efficient neural network reconstruction in canines with traumatic brain injury

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Regenerative Biomaterials 2022年第1期9卷 572-584页

作者： Xiaoyin Liu Guijun zhang Pan Wei Lin Zhong Yaxing Chen jianyong zhang Xuyi Chen Liangxue Zhou Department of Neurosurgery West China HospitalWest China Medical SchoolSichuan UniversityChengdu 610041SichuanChina Department of Neurosurgery The First People’s Hospital Of Long Quan yi DistrictChengdu 610000SichuanChina Tianjin Key Laboratory of Neurotrauma Repair Pingjin Hospital Brain CenterCharacteristic Medical Center of People’s Armed Police ForcesTianjin 300162China The First Affiliated Hospital of Chengdu Medical College Chengdu 610500SichuanChina Department of General Surgery the Affiliated Hospital of Guizhou Medical UniversityGuiyang CN 540000P.R.GuizhouChina Institute of Medical Security for Maritime Rights Protection of Characteristic Medical Center of Chinese People’s Armed Police Force(PAP) Tianjin300162China

The secretome secreted by stem cells and bioactive material has emerged as a promising therapeutic choice for traumatic brain injury(TBI).We aimed to determine the effect of 3D-printed collagen/chitosan/secretome derived from human umbilical cord blood mesenchymal stem cells scaffolds(3D-CC-ST)on the injured tissue regeneration process.3D-CC-ST was performed using 3D printing technology at a low temperature(20C),and the physical properties and degeneration rate were measured.The utilization of low temperature contributed to a higher cytocompatibility of fabricating porous 3D architectures that provide a homogeneous distribution of cells.Immediately after the establishment of the canine TBI model,3D-CC-ST and 3D-CC(3D-printed collagen/chitosan scaffolds)were implanted into the cavity of TBI.Following implantation of scaffolds,neurological examination and motor evoked potential detection were performed to analyze locomotor function recovery.Histological and immunofluorescence staining were performed to evaluate neuro-regeneration.The group treated with 3D-CC-ST had good performance of behavior functions.Implanting 3D-CC-ST significantly reduced the cavity area,facilitated the regeneration of nerve fibers and vessel reconstruction,and promoted endogenous neuronal differentiation and synapse formation after TBI.The implantation of 3D-CC-ST also markedly reduced cell apoptosis and regulated the level of systemic inflammatory factors after TBI.

关键词： traumatic brain injury canines secretome low temperature extrusion 3D printing collagen chitosan

Continuous flow synthesis of porous materials

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Chinese Chemical Letters 2020年第6期31卷 1448-1461页

作者： Yu Xin Sheng Peng Junxing Chen Zujin Yang jianyong zhang MOE Laboratory of Polymeric Composite and Functional Materials School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China

Porous materials play an important role in chemical catalysis,separation and other industrial applications.High-efficiency preparation of porous materials has become an active research area.Conventional synthesis of porous materials has been dominated by one-pot solution processing conditions carried out by bulk mixing under conventional electric heating via hydrothermal,solvothermal or ionothermal reactions where high temperatures and pressures are the standard.Continuous flow synthesis has many key advantages in terms of efficient mass and heat transfer,precise control of residence times,improved opportunities for automation and feedback control of synthesis,scaling-up reactions and improved safety parameters compared to above mentioned conventional batch scale synthetic methods.In this review,continuous flow synthesis of various crystalline porous materials such as metal-organic frameworks(MOFs),covalent-organic frameworks(COFs),porous organic cages and zeolites is discussed.Combination of microfluidic methods with other techniques are also shown including various heating ways and various methods of substrate adding.

关键词： Porous materials Continuous flow Metal-organic frameworks Zeolites Covalent-organic frameworks