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建筑固废再生骨料单颗粒压碎试验与近场动力学模拟

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中南大学学报（自然科学版） 2024年第9期55卷 3368-3383页

作者：肖源杰侯可华文俊王小明杨涛王萌陈宇亮周震孟凡威中南大学土木工程学院湖南长沙410075 中南大学重载铁路工程结构教育部重点实验室湖南长沙410075 湖南省交通科学研究院有限公司湖南长沙410114 广东省交通规划设计研究院集团股份有限公司广东广州510507

建筑固废再生骨料颗粒形状复杂、强度低且极易发生破碎。为了准确了解建筑固废再生骨料颗粒在单轴压缩荷载作用下的颗粒破碎行为,开展再生骨料单颗粒压碎试验,并在准确表征再生骨料颗粒三维形貌的基础上对单颗粒破碎进行近场动力学模拟... 详细信息

建筑固废再生骨料颗粒形状复杂、强度低且极易发生破碎。为了准确了解建筑固废再生骨料颗粒在单轴压缩荷载作用下的颗粒破碎行为,开展再生骨料单颗粒压碎试验,并在准确表征再生骨料颗粒三维形貌的基础上对单颗粒破碎进行近场动力学模拟。研究结果表明:碎石、红砖和砂浆这3种再生骨料的单颗粒破碎强度均较好地满足Weibull分布,但离散性较大,不同粒径组的平均Weibull模量在1.3~1.8之间,其中,砂浆与红砖颗粒的破碎强度远低于碎石颗粒的破碎强度,且离散性比碎石颗粒的大;借助近场动力学理论可以有效地模拟真实形状再生骨料颗粒在单轴压缩荷载作用下的破碎过程;对于不同形状种类的再生骨料颗粒破碎强度,块状颗粒的最大,盘状颗粒的次之,而条状颗粒的最小;颗粒材料与形状对颗粒破碎后所形成的碎片的数量与形状具有明显的影响,对于不同材料再生骨料颗粒,碎石颗粒产生碎片较少,而红砖颗粒产生碎片分布更加均匀;对于不同形状再生骨料颗粒,条状颗粒倾向于沿颗粒中、短轴平面断裂为少量碎片,块状与盘状颗粒则倾向于产生交叉裂纹,最终破碎并产生较多碎片。

关键词：建筑固废颗粒破碎 Weibull分布数值模拟近场动力学

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老挝固体钾盐尾矿低成本胶凝固化材料研究

矿业研究与开发 2024年第5期44卷 66-73页

作者：郑伯坤石勇黄腾龙彭亮郑博洋尹旭岩周晃江科长沙矿山研究院有限责任公司湖南长沙410012 金属矿山安全技术国家重点实验室湖南长沙410012 湖南省矿山固废综合利用工程技术研究中心湖南长沙410012

为解决钾盐尾矿尾盐与老卤难固结以及固结成本高等难题,开展了传统常规胶凝材料与尾盐的强度配比试验,分析尾盐的固结特性,根据尾盐的特性,研发了两种新型胶凝材料,并探究了新型胶凝材料在不同灰砂比和质量浓度下与尾盐的固结强度。研... 详细信息

为解决钾盐尾矿尾盐与老卤难固结以及固结成本高等难题,开展了传统常规胶凝材料与尾盐的强度配比试验,分析尾盐的固结特性,根据尾盐的特性,研发了两种新型胶凝材料,并探究了新型胶凝材料在不同灰砂比和质量浓度下与尾盐的固结强度。研究结果表明,以氧化钙作为胶凝材料,当灰砂比较大时,其与尾盐混合后的固结效果差,试块抗压强度低,而随着灰砂比的降低,试块的最佳强度可达到1.20 MPa;氧化镁可以显著提升尾盐充填体的强度,试块28 d强度最高可达22.06 MPa;粉煤灰和钢渣作为胶凝材料时,尾盐和老卤无法实现固结,不宜作为尾盐的胶凝材料。1^(#)新型胶凝材料与尾盐混合固结后试块的强度偏低,最高强度仅达到1.20 MPa,不能满足充填体的强度要求,但其能降低充填体表面的粗糙程度;2^(#)新型胶凝材料在灰砂比为1∶8且料浆质量浓度为72%时,试块的28 d强度可以达到3.17 MPa;与氧化镁相比,当试块强度达到2.00~3.00 MPa时,胶凝材料的充填成本降低了50%以上。

关键词：钾盐尾矿尾盐胶凝固化材料充填体强度充填成本

珠江口潜水镭同位素时空特征及其对海底地下水排泄通量测算的影响研究

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矿物岩石地球化学通报 2024年第3期43卷 541-552页

作者：吴才华张泽彬王亚周永章朱雅敏赵新锋李清洋李镇雄中山大学地球科学与工程学院广东珠海519082 南方海洋科学与工程广东省实验室(珠海) 广东珠海519082 广东省地质过程与矿产资源探查重点实验室广州510275 广东省珠海生态环境监测站广东珠海519070 自然资源部珠海海洋中心广东珠海519015

准确选取具有代表性的地下水端元是采用镭同位素示踪法量化海底地下水排泄(SGD)通量的关键。本研究分析了珠江三角洲潜水^(224)Ra与^(223)Ra的时空分布特征,评估了其对SGD通量计算的影响。结果表明,从潮间带近端至远端,潮间带潜水盐度... 详细信息

准确选取具有代表性的地下水端元是采用镭同位素示踪法量化海底地下水排泄(SGD)通量的关键。本研究分析了珠江三角洲潜水^(224)Ra与^(223)Ra的时空分布特征,评估了其对SGD通量计算的影响。结果表明,从潮间带近端至远端,潮间带潜水盐度和镭活度总体上表现为先下降后升高;相近盐度下,不同潮滩潮间带潜水镭活度无量级差别,仅随盐度上升的变化趋势略有差异;河口内外潮间带潜水的^(224)Ra活度最大相差(1986.8±94.5)dpm/100L,导致测算的SGD差异可达(25.2±9.6)×10^(8)m^(3)/d;以砂质潮滩为例,测算的旱、雨季SGD通量差异可达(2.3±1.6)×10^(8)m^(3)/d。SGD通量对潜水端元取值的敏感性分析显示,盐度影响最大,季节影响次之,潮滩性质影响最小。因此选择镭同位素趋近解吸平衡的高盐度潮间带潜水作为代表性潜水端元进行SGD通量测算较为合理。

关键词：镭同位素镭质量平衡模型盐度潜水端元潮间带潜水

Noise Suppression of a Single Frequency Fiber Laser

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Chinese Physics Letters 2011年第7期28卷 156-159页

作者： LIU Kui CUI Shu-zhen ZHANG Hai-Long ZHANG Jun-Xiang GAO jiang-Rui State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006

We present an experimental demonstration of fiber laser noise suppression by the mode *** intensity noise of a single frequency fiber laser is suppressed near the shot noise limit after a sideband frequency of 3 *** s... 详细信息

关键词： fiber noise laser

Relay camera videometrics based conversion method for unstable platform to static reference

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Science China(Technological Sciences) 2011年第4期54卷 1017-1023页

作者： YU QiFeng SUN XiangYi jiang GuangWen LIU XiaoLin ZHANG XiaoHu zhou Jian SHANG Yang College of Aerospace and Materials Engineering National University of Defense TechnologyChangsha 410073China 2 College of Optoelectronic Science and Engineering National University of Defense TechnologyChangsha 410073China College of Mechatronic Engineering and Automation National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory for Image Measurement and Vision Navigation Changsha 410073China

This article proposes a relay camera videometrics based method to convert an unstable measuring platform to a static reference to solve the problems of large error or invalidation caused by measuring platform instability in photogrammetric and videometric *** method installs a relay camera on the unstable platform and captures images of a reference marker fixed on a static reference or vice versa to resolve the 3D movement of the unstable platform relative to the static reference,based on which it corrects the error of the measured results and thus eliminating the influence of the platform *** finds new and important applications for videometrics by making high-precision dynamic measurement possible on unstable *** experiments and numerical simulations have proven its validity and practicability.

关键词： optical measurement videometrics unstable platform static reference conversion

Novel Ag-bridged dual Z-scheme g-C_(3)N_(4)/BiOI/AgI plasmonic heterojunction: Exceptional photocatalytic activity towards tetracycline and the mechanism insight

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Journal of Environmental Sciences 2023年第9期131卷 123-140页

作者： Wenxia Wang zhen Li Kailin Wu Guodong Dai Qingping Chen Lihua zhou Junxia zheng Liang Ma Guiying Li Wanjun Wang Taicheng An School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key lab of Clean Transport Energy and Chemistry Guangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Rational design and synthesis of highly efficient and robust photocatalysts with positive exciton splitting and interfacial charge transfer for environmental applications is ***,aiming at overcoming the common shortcomings of traditional photocatalysts such as weak photoresponsivity,rapid combination of photo-generated carriers and unstable structure,a novel Ag-bridged dual Z-scheme g-C_(3)N_(4)/BiOI/AgI plasmonic heterojunction was successfully synthesized using a facile *** showed that Ag-AgI nanoparticles and three-dimensional(3D)BiOI microspheres were decorated highly uniformly on the 3D porous g-C_(3)N_(4) nanosheet,resulting in a higher specific surface area and abundant active *** optimized 3D porous dual Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI manifested exceptional photocatalytic degradation efficiency of tetracycline(TC)in water with approximately 91.8%degradation efficiency within 165 min,outperforming majority of the reported g-C_(3)N_(4)-based ***,g-C_(3)N_(4)/BiOI/Ag-AgI exhibited good stability in terms of activity and ***-depth radical scavenging and electron paramagnetic resonance(EPR)analyses confirmed the relative contributions of various *** analysis indicated that the improved photocatalytic performance and stability were ascribed to the highly ordered 3D porous framework,fast electron transfer of dual Z-scheme heterojunction,desirable photocatalytic performance of BiOI/AgI and synergistic effect of Ag ***,the 3D porous Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI heterojunction had a good prospect for applications in water *** current work provides new insight and useful guidance for designing novel structural photocatalysts for environment-related applications.

关键词： Three-dimensional Porous heterostructure Graphitic carbon nitride(g-C_(3)N_(4)) Dual Z-scheme heterojunction Tetracycline(TC)degradation Mechanism insight

Sequential Recommendation via Cross-Domain Novelty Seeking Trait Mining

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Journal of Computer Science & Technology 2020年第2期35卷 305-319页

作者： Fu-zhen Zhuang Ying-Min zhou Hao-Chao Ying Fu-zheng Zhang Xiang Ao Xing Xie Qing He Hui Xiong Key Laboratory of Intelligent Information Processing of Chinese Academy of Sciences Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Public Health Zhejiang University School of MedicineHangzhou 310027China Meituan-Dianping Group Beijing 100102China Microsoft Research Asia Beijing 100080China Department of Management Science and Information Systems Rutgers UniversityNew Jersey 07102U.S.A.

Transfer learning has attracted a large amount of interest and research in last decades, and some effort has been made to build more precise recommendation systems. Most previous transfer recommendation systems assume that the target domain shares the same/similar rating patterns with the auxiliary source domain, which is used to improve the recommendation performance. However, almost all existing transfer learning work does not consider the characteristics of sequential data. In this paper, we study the new cross-domain recommendation scenario by mining novelty-seeking trait. Recent studies in psychology suggest that novelty-seeking trait is highly related to consumer behavior, which has a profound business impact on online recommendation. Previous work performed on only one single target domain may not fully characterize users' novelty-seeking trait well due to the data scarcity and sparsity, leading to the poor recommendation performance. Along this line, we propose a new cross-domain novelty-seeking trait mining model (CDNST for short) to improve the sequential recommendation performance by transferring the knowledge from auxiliary source domain. We conduct systematic experiments on three domain datasets crawled from Douban to demonstrate the effectiveness of our proposed model. Moreover, we analyze the directed influence of the temporal property at the source and target domains in detail.

关键词： sequential recommendation novelty-seeking trait transfer learning

Protective Effect of Hydroxy safflor Yellow A against Chronic Mild Stress-induced Memory Impairments by Suppressing Tau Phosphorylation in Mice

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Current Medical Science 2021年第3期41卷 555-564页

作者： Ying WANG Qiang WANG Jun CHEN Li-he YAO Ni TANG zhen-xiu jiang Yu LUO Department of Neurology The First Hospital of Lanzhou UniversityLanzhou 730000China Institute of Pathophysiology School of Basic Medical SciencesLanzhou UniversityLanzhou 730000China

Chronic stress plays a critical role in the etiology of sporadic Alzheimer's disease(AD).However,there are currently no effective drugs that can target chronic stress to prevent *** this study,we explored the neuroprotective effect of hydroxysafflor yellow A(HSYA)against chronic mild stress(CMS)-induced memory impairments in mice and the underlying *** Morris water maze test showed that HSYA significantly reduced CMS-induced learning and memory impairments in *** increased the expression of brain-derived neurotrophic factor(BDNF)and activated downstream tropomyosin-related kinase B(TrkB)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)*** decreased the expression of regulator of calcineurin 1-1L(RCAN1-1L)that could promote the activity of glycogen synthase kinase-3β(GSK-3β).HSYA also attenuated tau phosphorylation by inhibiting the activity of GSK-3βand cyclin-dependent kinase-5(Cdk5).Our data indicated that HSYA has protective effects against CMS-induced BDNF downregulation,tau phosphorylation and memory *** may be a promising therapeutic candidate for AD by targeting chronic stress.

关键词： Alzheimer's disease chronic stress hydroxysafflor yellow A tau phosphorylation brain-derived neurotrophic factor

Formation of Phosphorous Surface Inverse Segregation in Twin-Roll Cast Strips of Low-Carbon Steels

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Journal of Iron and Steel Research International 2011年第2期18卷 18-23页

作者： zhou Guo-ping LIU zhen-yu YU Shi-chuan CHEN Jun QIU Yi-qing WANG Guo-dong Strip Cold Rolling Plant Tangshan Iron and Steel Group Tangshan 063016 Hebei China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

The formation of phosphorous surface inverse segregation （SIS） in twin-roll cast strips of low-carbon steels was studied. High phosphorous strips were fabricated by using a pilot twin-roll strip caster and a melt/substrate contacting apparatus, respectively. Solidification structures of strips were observed and analyzed, and phosphorus distributions along longitudinal sections of strips were investigated and discussed. The results showed that solidification structures of all strips were columnar grains, either integrated or coarse in the strip made by the melt/substrate contacting apparatus or damaged in some degree in cast strips; and that during cast strip solidification, enrichment of phosphorus occurred between columnar grains, and the average phosphorus concentration near the surface in the strip with 0.15% of phosphorus was measured to be about 0.27% which was obviously higher than that in the bulk.

关键词： strip casting phosphorus enrichment inverse segregation steel solidification