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mechanical properties of municipal solid waste incineration residues with cement and coal fly ash using X-rayComputed Tomography scanners

Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA

《结构与土木工程前沿（英文）》 2019年第13卷第3期页码 640-652 doi: 10.1007/s11709-018-0502-6

摘要： A significant volume of Municipal Solid Waste incineration bottom ash and fly ash (i.e., incineration residues) are commonly disposed as landfill. Meanwhile, reclamation of landfill sites to create a new land space after their closure becomes an important goal in the current fewer and fewer land availability scenario in many narrow countries. The objective of this study is to reclaim incineration residue materials in the landfill site by using cement and coal fly ash as stabilizers aiming at performing quality check as new developed materials before future construction. Indeed, physical and mechanical properties of these new materials should be initially examined at the micro scale, which is the primary fundamental for construction at larger scale. This research examines quantitative influences of using the combination of cement and coal fly ash at different ratio on the internal structure and ability of strength enhancement of incineration residues when suffering from loading. Couple of industrial and micro-focus X-ray computed tomography (CT) scanners combined with an image analysis technique were utilized to characterize and visualize the behavior and internal structure of the incineration residues-cement-coal fly ash mixture under the series of unconfined compression test and curing period effect. Nine types of cement solidified incineration residues in term of different curing period (i.e., 7, 14, 28 days) and coal fly ash addition content (i.e., 0%, 9%, 18%) were scanned before and after unconfined compression tests. It was shown that incineration residues solidified by cement and coal fly ash showed an increase in compression strength and deformation modulus with curing time and coal fly ash content. Three-dimension computed tomography images observation and analysis confirmed that solidified incineration residues including incineration bottom and fly ash as well as cement and coal fly ash have the deliquescent materials. Then, it was studied that stabilized parts play a more important role than spatial void distribution in increment or reduction of compression strength.

关键词： mechanical property municipal solid waste incineration residues coal fly ash unconfined compression test image analysis X-Ray Computed Tomography scanners

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A study on quality evaluation for bituminous mixture using X-ray CT

Satoshi TANIGUCHI, Keiichiro OGAWA, Jun OTANI, Itaru NISHIZAKI

《结构与土木工程前沿（英文）》 2013年第7卷第2期页码 89-101 doi: 10.1007/s11709-013-0197-7

摘要： The objective of this paper is to propose a new quality evaluation method for asphalt concrete mixture using X-ray CT scanner. To achieve this aim, asphalt mixtures should be subjected to the X-ray CT scanning and its characteristics should be clarified. The approach employed in this study was as follows: 1) Coarse aggregate, fine aggregate, filler and bitumen were prepared; 2) dense-graded, coarse-graded and porous asphalt mixtures were made; 3) materials and mixtures were subjected to the X-ray CT scanning; 4) frequency of CT-value, threshold value, average slice CT-value, average segment CT-value were computed. In the material examination, CT-value of aggregate becomes smaller in the order of coarse aggregate, fine aggregate and filler and CT image of bitumen was nearly homogeneous. In the mixture examination, histograms of CT-value and four segmentation images made from CT images expressed the material and mixture characterization such as particle size and the difference in bitumen content and mixture type visibly and the bitumen content varies with the threshold values. In addition, the average segment CT-value without threshold value by dividing the fine aggregate from the coarse aggregate and average CT-value of the coarse aggregate, especially is highly correlated with average CT-value of the bitumen.

关键词： asphalt concrete mixture aggregate bitumen bitumen content quality evaluation X-ray CT

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Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy

Junyi DU, Daishe WU, Huayun XIAO, Ping LI

《环境科学与工程前沿（英文）》 2011年第5卷第2期页码 212-226 doi: 10.1007/s11783-010-0255-5

摘要： This research investigates the adsorption mechanisms of fluoride (F) on four clay minerals (kaolinite, montmorillonite, chlorite, and illite) under different F concentrations and reaction times by probing their fluoride superficial layer binding energies and element compositions using X-ray photoelectron spectroscopy (XPS). At high F concentrations ( = 5–1000 mg·L ), the amount of F adsorbed ( ), amount of hydroxide released by clay minerals, solution F concentration, and the pH increase with increasing . The increases are remarkable at >50 mg·L . The increases significantly by continuously modifying the pH level. At <5–100 mg·L , clay minerals adsorb H to protonate aluminum-bound surface-active hydroxyl sites in the superficial layers and induce F binding. As the increases, F , along with other cations, is adsorbed to form a quasi-cryolite structure. At >100 mg·L , new minerals precipitate and the product depends on the critical Al concentration. At [Al ]>10 mol·L , cryolite forms, while at [Al ]<10 mol·L , AlF is formed. At low (0.3–1.5 mg·L ), proton transfer occurs, and the F adsorption capabilities of the clay minerals increase with time.

关键词： clay mineral fluoride (F) adsorption mechanism X-ray photoelectron spectroscopy (XPS)

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Fatigue of asphalt binder, mastic and mixture at low temperature

Dong WANG, Linbing WANG, Guoqing ZHOU

《结构与土木工程前沿（英文）》 2012年第6卷第2期页码 166-175 doi: 10.1007/s11709-012-0157-7

摘要： The fatigue damage is one of the most common distresses observed on the asphalt concrete pavement. To thoroughly understand the fatigue of asphalt concrete, the behaviors of the major components of asphalt concrete under cyclic loading are investigated respectively in this study. A new experiment method is developed to evaluate the performances of asphalt binder, mastic and fine aggregates mixture under cyclic tensile loading. The fatigue test results of asphalt binder show that the fatigue performance of asphalt binder is closely related with loading magnitude, temperature and loading rate. Mastic specimens with different filler content are tested and the results indicate that mastic specimens with 30% filler content show better fatigue resistance and higher permanent strain. The micro-structure analysis of mastic and mixture indicates that the fatigue resistance is closely related with the air void content of specimen. 3D digital specimens are developed to model the fatigue of the asphalt binder, mastic and mixture specimens based on the finite element method (FEM). Fatigue damage of asphalt concrete is simplified by a damage model. With proper selection of damage parameters, the simulation results agree well with laboratory test results and can be used as a basis for future fatigue research.

关键词： fatigue asphalt mixture asphalt binder mastic finite element method (FEM) X-ray tomography

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Error analysis of the parameters for non-coaxial grazing X-ray microscope

ZHAO Lingling, HU Jiasheng, LI Xiang

《机械工程前沿（英文）》 2007年第2卷第3期页码 323-329 doi: 10.1007/s11465-007-0057-z

摘要： A non-coaxial grazing X-ray microscope, consisting of four spherical mirrors, is designed for diagnosis of inertial confinement fusion (ICF). The aberrations and imaging quality of the microscope are analyzed. To acquire excellent imaging quality, suitable tolerances for manufacturing and assembling the microscope are necessary. This paper researches the changes of Gauss parameters and aberrations due to component and subsystem parameters (such as the radius of the mirror, angle between mirrors, grazing angle, object distance, etc.). Here, spot diagrams and modulation transfer function (MTF) are first adopted to quantitatively evaluate the imaging quality of the microscope. Suitable manufacturing tolerances of components and assembly tolerances of the system are established on the basis of the discussion and analysis. A set of non-coaxial grazing X-ray microscopes is manufactured based on the tolerances. In site tests of ICF, the images with high resolution are obtained by the microscope.

关键词： non-coaxial spherical manufacturing necessary diagnosis

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Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

《环境科学与工程前沿（英文）》 2015年第9卷第2期页码 216-221 doi: 10.1007/s11783-014-0630-8

摘要： The interaction of the fly ash and NaOH, in an open reflux hydrothermal system at 100°C, has been explored by several researchers and formation of fly ash zeolites has been confirmed based on the X-ray diffraction analysis of the residues. However, this method does not reveal much about the characteristic transitions (viz. elemental, electro-negativity and cation exchange capacity) of the residues. In this situation, resorting to Fourier transform-infrared radiation (FT-IR) spectroscopy on the residues obtained from two-stage hydrothermal treatment process, described in this manuscript, appears to be a novel idea to establish transitions in chemical bonds (viz., -Si-OH-Al-, OH-Na, OH-Al-), crystallinity and cation exchange capacity of these residues. Based on extensive studies, it has been demonstrated that FT-IR spectroscopy is extremely useful for 1) detection of chemical bonds in the residues, 2) evaluation of zeolites in the residues and 3) also establishing the superiority of the two-stage interaction of the fly ash with NaOH for synthesizing better fly ash zeolites (viz., Na-P1 and Hydroxysodalte) as compared to those obtained from the conventional single-stage treatment of the fly ash.

关键词： hydrothermal treatment alkali activation fly ash zeolites X-ray diffraction (XRD) and Fourier transform-infrared radiation (FT-IR) spectroscopy

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采用白光X射线源和模拟阵列能量色散阵列探测器的高通量粉末衍射技术 Article

汪晓平, 董伟伟, 张鹏, 唐浩琪, 张澜庭, 杨铁莹, 刘鹏, 汪洪, 项晓东

《工程（英文）》 2022年第10卷第3期页码 81-88 doi: 10.1016/j.eng.2021.05.023

摘要： text-align: justify;">在上海同步辐射光源（SSRF）的弯铁光束线上，利用由空间扫描硅漂移探测器（SDD）模拟获得的能量色散阵列探测器，对CeO₂样品进行高通量白光X射线粉末衍射校正后的衍射图谱表明，由能量色散X 射线衍射（EDXRD）获得的不同衍射峰之间的相对强度与来自角度分辨X射线衍射（ARXRD）的相对强度一致，说明EDXRD结果可用于分析未知样品的晶体结构。实验同时采集了X射线荧光（XRF）信号。来自所有像素的XRF计数可直接在能量坐标下叠加，而衍射信号则需在d 空间下叠加，从而大大改善了阵列探测器的峰值强度和信噪比（S/N）。与ARXRD相比，白光X射线衍射信号强度是单色光衍射信号强度的10⁴倍左右。

关键词：高通量实验白光X射线衍射能量色散阵列探测器能量色散X射线衍射角分辨X射线衍射

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analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

《结构与土木工程前沿（英文）》 2012年第6卷第2期页码 85-100 doi: 10.1007/s11709-012-0159-5

摘要： The ground subsidence on the underground pipe often is caused with the reduction of the effective stress and the loss of suction in the base course and then, soil drainage into the pipe. The final formation of the cavity growth in the ground was observed as the ground subsidence. Authors focused this problem and hence performed model tests with water-inflow and drainage cycle in the model ground. The mechanism of cavity generation in the model ground was observed using an X-ray Computed Tomography (CT) scanner. In those studies, water was supplied into the model grounds from the defected underground pipe model in case of the change of relative density and grain size distribution. As results, it was observed that the loosening area was generated from the defected part with water-inflow and some of the soil particles in the ground were drained into the underground pipe through the defected part. And afterward, the cavity was generated just above the defected part of the model pipe in the ground. Based on this observation, it might be said that the bulk density of soil around the defected pipe played one of key factor to generate the cavity in the ground. Moreover, the dimension of the defected part should be related to the magnification of the ground subsidence, in particular, crack width on a sewerage pipe and particle size would be the quantitative factor to evaluate the magnification of the ground subsidence. ?In this paper, it was concluded that the low relative density of soil would become the critical factor to cause the fatal failure of model ground if the maximum grain size was close to the dimension of crack width of defective part. The fatal collapse of the ground with high relative density more than 80% would be avoided in a few cycles of water inflow and soil drainage.

关键词： relative density grain property model test road subsidence underground pipe image processing X-ray CT

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Design of efficient Pt-based electrocatalysts through characterization by X-ray absorption spectroscopy

Nebojsa S. MARINKOVIC, Kotaro SASAKI, Radoslav R. ADZIC

《能源前沿（英文）》 2017年第11卷第3期页码 236-244 doi: 10.1007/s11708-017-0487-1

摘要： A method is described to determine the internal structure of electrocatalyst nanoparticles by X-ray absorption spectroscopy (XAS). The nondestructive spectroscopic technique typically utilizing synchrotron radiation as the source measures changes in the X-ray absorption coefficient as a function of energy. The bulk technique has found its use for materials characterization in all scientific areas, including nanomaterials. The analysis of the internal structure of nanoparticles reveals interatomic distances and coordination numbers for each element, and their values and mutual relations indicate whether the elements form a homogeneous or heterogeneous mixture. The core-shell heterogeneous structure in which certain elements are predominantly located in the core, and others form the encapsulating shell is of particular importance in catalysis and electrocatalysis because it may reduce the amount of precious metals in nanoparticles by replacing the atoms in the core of nanoparticles with more abundant and cheaper alternatives. The examples of nanoparticle structures designed in the laboratory and the approach to model efficient catalysts through systematic analysis of XAS data in electrochemical systems consisting of two and three metals are also demonstrated.

关键词： X-ray absorption spectroscopy EXAFS XANES nanocatalysts core shell

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β-Nickel hydroxide cathode material for nano-suspension redox flow batteries

Yue LI, Cheng HE, Elena V. TIMOFEEVA, Yujia DING, Javier PARRONDO, Carlo SEGRE, Vijay RAMANI

《能源前沿（英文）》 2017年第11卷第3期页码 401-409 doi: 10.1007/s11708-017-0496-0

摘要： As part of an effort to build a prototype flow battery system using a nano-suspension containing β-Ni(OH) nanoparticles as the cathode material, nano-sized β-Ni(OH) particles with well-controlled particle size and morphology were synthesized via the one-step precipitation of a NiCl precursor. The composition and morphology of the nanoparticles were characterized by scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The XRD patterns confirmed that β-Ni(OH) was successfully synthesized, while SEM results showed that the particle sizes range from 70 to 150 nm. To ensure that Ni(OH) could be employed in the nano-suspension flow battery, the electrochemical performance of the synthesized β-Ni(OH) was initially tested in pouch cells through charge/discharge cycling. The phase transformations occurring during charge/discharge were investigated using X-ray absorption spectroscopy to obtain the shift in the oxidation state of Ni (X-ray adsorption near edge structure, XANES) and the distances between Ni and surrounding atoms in charged and discharged states (extended X-ray absorption fine structure, EXAFS). XANES results indicated that the electrode in the discharged state was a mixture of phases because the edge position did not shift back completely. XAFS results further proved that the discharge capacity was provided by β-NiOOH and the ratio between β-Ni(OH) and g-NiOOH in the electrode in the discharged state was 71:29. Preliminary nano-suspension tests in a lab-scale cell were conducted to understand the behavior of the nano-suspension during charge/discharge cycling and to optimize the operating conditions.

关键词： nano-suspension flow battery β-Ni(OH)₂ scanning electronic microscopy (SEM) X-ray diffraction (XRD) X-ray adsorption near edge structure (XANES) extended X-ray absorption fine structure (EXAFS)

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脉冲X射线模拟技术的发展

邱爱慈

《中国工程科学》 2000年第2卷第9期页码 24-28

摘要：

文章简要介绍了利用强流脉冲电子束加速器模拟脉冲X射线的发展概况及国内脉冲X射线模拟源的发展现状，指出作为主要技术途径，高功率Z箍缩技术在实现超强脉冲X射线源和ICF驱动源上都有很重要的发展应用前景

关键词：脉冲X射线高功率脉冲技术脉冲电子束加速器 Z箍缩 ICF

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Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

《化学科学与工程前沿（英文）》 2016年第10卷第2期页码 196-202 doi: 10.1007/s11705-016-1565-3

摘要： X-ray crystallography is a powerful strategy for 3-D structure determination of macromolecules, such as nucleic acids and protein-nucleic acid complexes. However, the crystallization and phase determination are the major bottle-neck problems in crystallography. Recently we have successfully developed synthesis and strategy of selenium-derivatized nucleic acids (SeNA) for nucleic acid crystallography. SeNA might not only provide the rational strategies to solve the phase determination problem, but also offer a potential strategy to explore crystallization solutions.

关键词： selenium DNA RNA nucleic acid crystallization

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Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 190-200 doi: 10.1007/s11709-018-0487-1

摘要： Split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC) was examined using two complementary techniques: X-ray computed tomography (CT) and acoustic emission (AE). Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load testing. From the CT images, fiber orientation was evaluated to establish optimum and pessimum specimen orientations, at which fibers would have maximum and minimum effect, respectively. As expected, fiber orientation affected both the peak load and the toughness of the specimen, with the optimum toughness being between 20% and 30% higher than the pessimum. Cumulative AE energy was also affected commensurately. Posttest CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for each. The results showed that fiber pullout was the dominant energy dissipation mechanism; however, the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of load. It is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词： ultra-high-performance concrete concrete fracture X-ray computed tomography acoustic emission

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高压纳米X射线成像技术的应用 Article

毛立文, 林昱, 刘宜晋, 刘锦

《工程（英文）》 2019年第5卷第3期页码 479-489 doi: 10.1016/j.eng.2019.01.006

摘要： "Times New Roman",serif">纳米级透射X射线显微镜（nanoscale transmission X-ray microscopy, nanoTXM）与金刚石对顶砧（diamond anvil cell, DAC）的结合，具有在极端条件下对材料进行高分辨率在本文中，我们讨论了当前高分辨率X射线成像的发展状况及其在第三代同步加速器X射线源中基于DAC的高压nanoTXM实验中的应用，包括为成功测量所需要的技术方面的考虑。

关键词： X射线成像高压金刚石对顶砧

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Characterization of 3D microstructure, thermal conductivity, and heat flow of cement-based foam using imaging technique

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 643-651 doi: 10.1007/s11709-021-0709-9

摘要： This study presents the results of the 3D microstructure, thermal conductivity, and heat flow in cement-based foams and examines their changes with a range of densities. Images were captured using X-ray micro computed tomography (micro-CT) imaging technique on cement-based foam samples prepared with densities of 400, 600, and 800 kg/m³. These images were later simulated and quantified using 3D data visualization and analysis software. Based on the analysis, the pore volume of 11000 µm³ was determined across the three densities, leading to optimal results. However, distinct pore diameters of 15 µm for 800 kg/m³, and 20 µm for 600 and 400 kg/m³ were found to be optimum. Most of the pores were spherical, with only 10% appearing elongated or fractured. In addition, a difference of 15% was observed between the 2D and 3D porosity results. Moreover, a difference of 5% was noticed between the experimentally measured thermal conductivity and the numerically predicted value and this variation was constant across the three cast densities. The 3D model showed that heat flows through the cement paste solids and with an increase in porosity this flow reduces.

关键词： 3D pore volume distribution X-ray tomography 3D shape factor heat flow

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标题作者时间类型操作

mechanical properties of municipal solid waste incineration residues with cement and coal fly ash using X-rayComputed Tomography scanners

Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA

期刊论文

A study on quality evaluation for bituminous mixture using X-ray CT

Satoshi TANIGUCHI, Keiichiro OGAWA, Jun OTANI, Itaru NISHIZAKI

期刊论文

Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy

Junyi DU, Daishe WU, Huayun XIAO, Ping LI

期刊论文

Fatigue of asphalt binder, mastic and mixture at low temperature

Dong WANG, Linbing WANG, Guoqing ZHOU

期刊论文

Error analysis of the parameters for non-coaxial grazing X-ray microscope

ZHAO Lingling, HU Jiasheng, LI Xiang

期刊论文

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

期刊论文

采用白光X射线源和模拟阵列能量色散阵列探测器的高通量粉末衍射技术

汪晓平, 董伟伟, 张鹏, 唐浩琪, 张澜庭, 杨铁莹, 刘鹏, 汪洪, 项晓东

期刊论文

analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

期刊论文

Design of efficient Pt-based electrocatalysts through characterization by X-ray absorption spectroscopy

Nebojsa S. MARINKOVIC, Kotaro SASAKI, Radoslav R. ADZIC

期刊论文

β-Nickel hydroxide cathode material for nano-suspension redox flow batteries

Yue LI, Cheng HE, Elena V. TIMOFEEVA, Yujia DING, Javier PARRONDO, Carlo SEGRE, Vijay RAMANI

期刊论文

脉冲X射线模拟技术的发展

邱爱慈

期刊论文

Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

期刊论文

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

期刊论文

高压纳米X射线成像技术的应用

毛立文, 林昱, 刘宜晋, 刘锦

期刊论文

Characterization of 3D microstructure, thermal conductivity, and heat flow of cement-based foam using imaging technique

期刊论文

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