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Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding zhe Sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

素混凝土桩和搅拌桩处理城市道路路基的原位试验

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中国公路学报 2007年第1期20卷 7-13页

作者：朱世哲陈秀亮徐日庆浙江大学土木工程学系浙江杭州310027 杭州经纬建筑工程有限公司浙江杭州310027

在较差地质条件、不同填筑材料情况下,用素混凝土桩和搅拌桩进行了城市道路路基处理的原位试验,分析了超孔隙水压力、桩间土分层沉降、附加有效应力、路基深层土的侧向位移等数据。结果表明:在正常荷载作用下,素混凝土桩复合地基浅层应... 详细信息

在较差地质条件、不同填筑材料情况下,用素混凝土桩和搅拌桩进行了城市道路路基处理的原位试验,分析了超孔隙水压力、桩间土分层沉降、附加有效应力、路基深层土的侧向位移等数据。结果表明:在正常荷载作用下,素混凝土桩复合地基浅层应力向桩体集中,并通过桩向深层扩散,桩顶和桩底的刺入较为明显,有单桩效应;而对于搅拌桩,大部分桩间土和桩没有相对位移,形成了一个加固整体,应力在桩顶和桩底较集中,大部分荷载传到了桩底桩间土和下卧层中。

关键词：道路工程城市道路路基试验研究素混凝土桩搅拌桩单桩效应加固整体

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双拱结构X型钢管相贯节点试验研究

浙江大学学报（工学版） 2008年第1期42卷 99-104,110页

作者：朱世哲罗尧治娄荣浙江大学空间结构研究中心浙江杭州310027

结合曹娥江新型双拱空间钢管结构闸门工程,对3种X型相贯节点形式(无加强、肋板加强型和套管加强型)进行了静载和反复加载试验.通过分析静载试验数据发现,相对于无加强节点试件,肋板加强型节点试件极限荷载提高不是很显著,套管加强型节... 详细信息

结合曹娥江新型双拱空间钢管结构闸门工程,对3种X型相贯节点形式(无加强、肋板加强型和套管加强型)进行了静载和反复加载试验.通过分析静载试验数据发现,相对于无加强节点试件,肋板加强型节点试件极限荷载提高不是很显著,套管加强型节点试件极限荷载提高较大.两种加强措施对于节点的局部应力减小作用不大.从极限荷载和局部应力两方面比较可知,对于支管的轴向刚度大于主管的径向刚度的节点,主管管壁的加强(套管加强型)是一种较为合适的方法.通过分析反复加载试验数据也发现,3种形式节点的滞回曲线都比较丰满,节点的延性较好,反复加载和单向加载节点试件的破坏形式相近.

关键词：肋板加强型节点套管加强型节点静载试验反复加载试验

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang Qing shi Guofan Zhang Yuxuan zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun shi zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

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双拱型钢管结构闸门模型试验研究

水利学报 2007年第9期38卷 1121-1127页

作者：罗尧治朱世哲刘旭辉林军浙江大学空间结构研究中心浙江杭州310027 浙江林学院国林学院浙江杭州311300 浙江省水利水电勘测设计院浙江杭州310002 绍兴市曹娥江大闸投资开发有限公司浙江绍兴312000

本文对浙江省曹娥江挡潮泄洪闸双拱型钢管结构闸门在涌潮荷载下的承重结构进行了静力和反复加载的缩尺模型试验。静力试验数据分析表明,双拱型钢管结构闸门的承重结构主要受力构件为正拱、反拱和弦杆,它们组成了共同受力系统,以承受轴... 详细信息

本文对浙江省曹娥江挡潮泄洪闸双拱型钢管结构闸门在涌潮荷载下的承重结构进行了静力和反复加载的缩尺模型试验。静力试验数据分析表明,双拱型钢管结构闸门的承重结构主要受力构件为正拱、反拱和弦杆,它们组成了共同受力系统,以承受轴向应力为主,沿跨度方向受力均匀,材料的利用率高,说明其形体是合理的。反复加载试验模拟了钱塘江涌潮荷载,考察了在设计使用寿命期内双拱型钢管结构闸门承重结构在涌潮荷载反复作用下的受力特性,论证了承重结构在设计使用寿命期内不会发生疲劳破坏。

关键词：双拱型钢管结构闸门静力试验反复加载试验

Skp2、p27^kip1蛋白在结直肠癌中的表达及其意义

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中华实验外科杂志 2008年第10期25卷 1279-1281页

作者：黄志军朱世泽郭启祥福建医科大学附属第二医院肿瘤科泉州362000 福建泉州医学高等专科学校

目的探讨Skp2蛋白在结直肠癌发生、发展中的作用及其与p27^kip1蛋白表达的关系。方法应用免疫组织化学法结合计算机图像分析检测结直肠癌（80例）、腺瘤（20例）、正常组织（20例）中Skp2蛋白和p27^kip1蛋白的表达。结果由正常结直肠黏... 详细信息

目的探讨Skp2蛋白在结直肠癌发生、发展中的作用及其与p27^kip1蛋白表达的关系。方法应用免疫组织化学法结合计算机图像分析检测结直肠癌（80例）、腺瘤（20例）、正常组织（20例）中Skp2蛋白和p27^kip1蛋白的表达。结果由正常结直肠黏膜、腺瘤到癌，Skp2阳性表达率为O％、55％、93．8％，呈上升趋势（P〈0．01）；p27^kip1阳性表达率为100％、95％、87．5％，呈下降趋势（P〈0．05）。结直肠癌中Skp2表达与p27^kip1表达呈负相关（r=-0．311，P〈0．01）。Skp2蛋白在癌组织中的表达与结喜肠癌的分化程度、淋巴转移有关（P〈0．05）。结论结直肠癌Skp2蛋白过表达与p27^kip1蛋白降解有关，Skp2蛋白过表达可能是结直肠癌发生、发展的原因之一。

关键词：结直肠肿瘤 Skp2蛋自泛素

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一种定向凝固叶片浇注系统的研究

铸造 2012年第1期61卷 81-83页

作者：李波祝世哲李雪潘国志中航工业沈阳黎明航空发动机(集团)有限责任公司辽宁沈阳110043

通过对某发动机低压涡轮工作叶片定向凝固用浇注系统的设计和研究,找出了浇注系统影响铸件定向凝固质量的因素,确定了可获得较高铸件合格率的设计方案。研究表明:在定向凝固浇注系统设计中,叶片分布方式和引晶位置直接影响到叶片定向凝... 详细信息

通过对某发动机低压涡轮工作叶片定向凝固用浇注系统的设计和研究,找出了浇注系统影响铸件定向凝固质量的因素,确定了可获得较高铸件合格率的设计方案。研究表明:在定向凝固浇注系统设计中,叶片分布方式和引晶位置直接影响到叶片定向凝固柱状晶生长状态和组织致密程度;叶片呈环形均布形成的温度场有利于柱晶沿[001]方向生长,呈扇形均布的组合方式不利于柱状晶定向生长。

关键词：定向凝固涡轮叶片浇注系统

Bifunctional bridging capping layer enables 24.5% efficiency of perovskite solar cells with polymer-based hole transport materials

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Science China Chemistry 2025年第1期68卷 350-359页

作者： Can zhu Yiyang Wang Lei Meng Beibei Qiu Jing Li Shucheng Qin Ke Hu Xin Jiang Wenbin Lai Minchao Liu zhe Liu Chenxing Lu Jinyuan Zhang Yongfang Li Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences School of Chemical Science University of Chinese Academy of Sciences Key Laboratory of Solid State Optoelectronic Devices of zhejiang Province College of Physics and Electronic Information Engineering Zhejiang Normal University Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of Sciences Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials ScienceSoochow University

Developing a bridge capping layer between perovskite and hole transport layer materials（HTMs） in the n-i-p perovskite solar cells（pero-SCs） is an effective approach to modify the morphology of HTMs and passivate the perovskite ***, we select the quinoxaline-based bifunctional passivation agent, quinoxalin-6-yl-methylamine hydrochloride（Qx MACl）,as the bridging layer, and a D-A copolymer PBQ12 containing the same quinoxaline unit as an HTM for the n-i-p pero-SCs. Due to the π-π stacking among the common quinoxaline units in the bridge layer and HTM, Qx MACl induces the π-π stacking of the PBQ12 film and improves the film morphology of HTMs with better conductivity. Additionally, Qx MACl can effectively passivate the perovskite surface, and PBQ12 possesses appropriate energy levels and high hole mobility. The pero-SCs based on FAPbI3with PBQ12/Qx MACl treatment showed a higher power conversion efficiency（PCE） of 24.05% and outstanding stability, maintaining 95.4% and 92.1% of its initial PCE after 750 h of storage and after over 800 h of thermal annealing at 85 °C, respectively. To further enhance the PCE of the PBQ12/Qx MACl-based devices, we developed a non-metal ion dopant for the PBQ12 HTM. Through trace doping of PBQ12 HTM by the non-metal ion dopant, the PCE of the PBQ12/Qx MACl-based devices reached 25.24%（the calibrated PCE of 24.55% by the National Institute of Metrology, China）.

关键词： D-A copolymer, hole transport materials, bifunctional bridge capping layer, passivation perovskite solar cells