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DyFe11Ti磁结构及其自旋重取向的中子衍射研究 Article

Olivier Isnard, Eder J. Kinast

《工程（英文）》 2020年 第6卷 第2期   页码 153-157 doi: 10.1016/j.eng.2019.11.009

摘要：

本文报道了通过中子粉末衍射探测DyFe11Ti的磁结构及其热演化规律。使用了变温中子衍射技术来测量磁矩及其取向的温度依赖性。Dy和Fe磁矩以反向平行的方式形成亚铁磁性耦合，其2 K时的易磁化方向是基面(a, b)内的[110]轴。随着温度的升高，该磁结构先后经历了两次自旋重取向现象。低温下，Dy磁矩较大，达到9.7μB，而在200 K时磁矩迅速下降到7.5μB。在Fe 8i位置观察到了最大的Fe磁矩。尽管磁结构发生了很大的变化，但在研究的温度范围内ThMn12型晶体结构一直保持不变。在第一阶段的自旋重取向温度（TSR1）时，观察到了易磁化轴的急剧倾斜；易磁化轴与晶体c轴之间的夹角从2 K的90°减小到200 K时的约20°（其中c轴是200 K以上的易磁化轴）；同时Dy和Fe磁矩保持反向平行耦合。

关键词： 中子衍射，磁相图，晶体结构    

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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：

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（pXRD）实验。考虑到与实验硬件和衍射角相关的多种因素，对数据进行了详细分析和校正。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。q 空间中衍射峰的半峰全宽（FWHM）取决于探测器的能量分辨率、探测器接收角范围和衍射角大小。如果实验参数选择得当，在当前能量色散探测器的能量分辨率下，EDXRD有可能实现与ARXRD相同甚至更小的半峰全宽。

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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波浪与外壁透空双筒柱的互相作用

滕斌,李玉成,孙路

《中国工程科学》 2001年 第3卷 第10期   页码 41-47

摘要：

对于波浪与透空外壁同轴双筒柱的相互作用问题，利用速度势的特征函数展开式和透空壁内流体速度与两壁间压力差成正比的线性模型，建立了一个线性解析解。应用这一模型开展了数值实验，用以检验孔隙系数和透空部分大小以及内外柱径之比对双筒柱上波浪力和波面高度的影响。计算结果表明，外壁孔隙系数和透空部分大小对波面升高和波浪荷载有很大影响，通过调整各个系数，应用双筒透空柱可以减小周围的波面高度及其上的波浪荷载。

关键词： 波浪绕射     波浪力     波面升高     有孔建筑     圆柱    

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Application of digital holography to circle flow bed boiler measurement

PU Shiliang, WANG Qinghui, CEN Kefa, Denis Lebrun, REN Kuanfang

《能源前沿（英文）》 2007年 第1卷 第2期   页码 218-222 doi: 10.1007/s11708-007-0029-3

摘要： The spatial distribution of particles in the boiler is very important in the study on the circle flow bed boiler (CFB). Digital in-line holography technique was applied to obtain the spatial and diameter distribution of the particles inside the boiler. A HE-NE laser was used to illuminate the particles inside the CFB through two glass windows and the in-line diffraction pattern was recorded by a CCD camera. The diffraction can be interpreted as a convolution between a family of wavelet functions and the object function. So the three-dimensional (3D) images of the particles in the two-phase flow were reconstructed by the convolution between diffraction pattern and wavelet functions. The particle diameters and 3D coordinates were calculated from the reconstructed 3D images by a series of image-processing methods, followed by a discussion of the experimental results.

关键词： HE-NE     function     convolution     two-phase     diffraction    

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Preparation and property of porous hydroxyapatite as an inorganic dispersant used in suspension polymerization

XU Kaqiu, XU Jiale, WANG Yuhong

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 49-54 doi: 10.1007/s11705-008-0004-5

摘要： The porous hydroxyapatite (HAP) for suspension polymerization dispersant was prepared using calcium carbonate and phosphoric acid as raw materials. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET nitrogen adsorption. The results show that the prepared HAP has a porous structure, low particle density, large specific surface area, uniform particle size and does not agglomerate easily between the particles. The preparation conditions for the HAP were optimized as follows: solid content of calcium carbonate aqueous suspension 90 g/L, concentration of phosphoric acid 1.0 mol/L, reaction/aging temperature 50°C, and aging time 3 h. The HAP prepared under optimal preparation conditions has 106.8 m·g of specific surface area, which is about 1.5–1.8 times as much as that of Japanese HAP or commercial HAP. Its application result in the suspension polymerization of styrene show that the porous HAP dispersant has high surface activity, excellent suspension dispersibility and stability and can markedly improve the quality of polystyrene beads.

关键词： diffraction     stability     nitrogen adsorption     phosphoric     aqueous suspension    

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Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

《化学科学与工程前沿（英文）》 2018年 第12卷 第3期   页码 433-439 doi: 10.1007/s11705-018-1743-6

摘要：

Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)3Ag]·solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)3Ag]·4CHCl3 in space group P1‾ is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)3Ag]·2CHCl3 in the cubic space group P213. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl···Cl contacts and interact via non-classical C–H···O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)3Ag]·2CHCl3 in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].

关键词： ditopic ligand     substituted acetylacetone     desolvation     diffraction    

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Synthesis and properties of polybenzazoles containing flexible methylene in backbone

XU Xiaohui, LIU Xiaoyun, ZHOU Chengjun, ZHUANG Qixin, HAN Zhewen

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 412-416 doi: 10.1007/s11705-008-0073-5

摘要： A novel series of polybenzazoles with rigid-rod benzoxazole cycle and soft methylene segment was designed and synthesized via solution condensation polymerizations from 4,6-diamino-1,3-benzenediol diphosphate, terephthalic acid and aliphatic dicarboxylic acid. The structures of polybenzazoles were characterized by means of FT-IR, H NMR and Wide-angle X-ray diffraction (WAXRD). All the polymers show excellent thermal stability and the s was above 471°C. The intrinsic viscosities [] of the polymers ranged from 0.8 to 0.9. The UV-Vis absorption peaks of the polymers in MSA were blue-shifted from 429 nm for PBO to 291 nm for PBOC7, and the Stokes shifts in PL spectra enlarged.

关键词： condensation     Wide-angle     absorption     excellent     diffraction    

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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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LiFePO/C cathode materials synthesized by co-precipitation and microwave heating

XU Yunlong, TAO Lili, MA Hongyan, HUANG Huaqing

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 422-427 doi: 10.1007/s11705-008-0082-4

摘要： LiFePO/C cathode materials were synthesized by a combination of co-precipitation and microwave heating using polyethylene glycol (PEG) as a carbon resource and the influence of microwave heating time on the structure and electrochemical performance of the materials was also discussed. The samples were characterized by X-ray diffraction (XRD), TEM, particle-size analysis and constant current charge-discharge experiment. The results show that the LiFePO/C heated for 9 min has a pure olive-type phase and excellent electrochemical performance. The initial discharge capacities of this sample are 154.3, 139.7, 123.9 mAh/g at the rates 0.1C, 0.2C, 1C at room temperature, respectively, and after 20 cycles remain 152.3, 134.3, 118.5 mAh/g, respectively.

关键词： polyethylene     electrochemical performance     combination     co-precipitation     diffraction    

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Catalysis and deactivation of montmorillonite K10 in the aryl O -glycosylation of glycosyl trichloroacetoimidates

Xiaoliu LI, Xinhao YAN, Zhiwei LI, Hua CHEN, Pingzhu ZHANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 342-347 doi: 10.1007/s11705-009-0279-1

摘要： The catalysis of montmorillonite K10 (MK10) for aryl -glycosylation of glycosyl trichloroacetimidates was investigated. It was found that the catalyst MK10 is deactivated gradually in the recycle glycosylation. The fresh and the deactivated catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA), and N adsorption-desorption. The results show that the eliminated trichloroacetamide molecule deposits on the MK10, which blocks and poisons the active sites, resulting in the deactivation of the catalyst. The regeneration of the deactivated MK10 by calcination was studied preliminarily.

关键词： photoelectron spectroscopy     adsorption-desorption     glycosylation     deactivated     diffraction    

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Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substituted perovskite carrier on the catalyst activities

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 59-64 doi: 10.1007/s11705-007-0012-x

摘要： The perovskite-type compound LaMnO was substituted for the part of La in position A and for the part of Mn in position B by citrate method. The phases were detected by X-ray diffraction. Powder morphologies were scanned by scanning electron microscopy. The valence of atoms was determined by X-ray photoelectron spectroscopy. It was found that the perovskite can form crystal defect and increase the proportion of high valence B element by doping. Active component Pd was loaded on various perovskite supports for synthesis of diphenyl carbonate. The results showed that the activities of catalysts in which supports have crystal defect by substitution were higher. It can be concluded that perovskite with defect structure by doping could lead to the formation of oxygen vacancy where the lattice oxygen became exchangeable with the oxygen gas. Also, this improved the redox process of the carrier by transferring electrons and activities of catalysts.

关键词： photoelectron spectroscopy     diphenyl carbonate     proportion     diffraction     perovskite    

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Characterization of chlorine and heavy metals for the potential recycling of bottom ash from municipal solid waste incinerators as cement additives

Boran WU, Dongyang WANG, Xiaoli CHAI, Fumitake TAKAHASHI, Takayuki SHIMAOKA

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0847-9

摘要： Industrial waste mixed with MSW is the main source of heavy metal in bottom ash. Chlorine content in bottom ash is controlled both by plastic and kitchen waste. Insoluble chlorine in Chinese MSWI bottom ash exists primarily as AlOCl. Bottom ash is an inevitable by-product from municipal solid waste (MSW) incineration plants. Recycling it as additives for cement production is a promising disposal method. However, the heavy metals and chlorine are the main limiting factors because of the potential environmental risks and corrosion of cement kilns. Therefore, investigating heavy metal and chlorine characteristics of bottom ash is the significant prerequisite of its reuse in cement industries. In this study, a correlative analysis was conducted to evaluate the effect of the MSW components and collection mode on the heavy metal and chlorine characteristics in bottom ash. The chemical speciation of insoluble chlorine was also investigated by synchrotron X-ray diffraction analysis. The results showed that industrial waste was the main source of heavy metals, especially Cr and Pb, in bottom ash. The higher contents of plastics and kitchen waste lead to the higher chlorine level (0.6 wt.%–0.7 wt.%) of the bottom ash. The insoluble chlorine in the MSW incineration bottom ash existed primarily as AlOCl, which was produced under the high temperature (1250℃) in incinerators.

关键词： Bottom ash     Chlorine     Heavy metals     Waste inputs     Synchrotron X-ray diffraction     AlOCl    

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荧光显纳镜在神经科学中的应用 Review

王杨云逗, 林剑, 张启明, 陈希, 栾海涛, 顾敏

《工程（英文）》 2022年 第16卷 第9期   页码 29-38 doi: 10.1016/j.eng.2020.11.010

摘要：

荧光显纳技术提供了克服光学显微镜中衍射极限分辨率障碍的成像技术，从而开辟了生物医学成像研究领域（尤其在神经科学领域）。本文回顾了最重要的荧光显纳技术，包括描述了该技术在阐明蛋白质结构和流动性、神经活动过程中涉及突触参数的实时测定、三维成像和纳米级神经活动跟踪等方面的应用。最后，讨论了荧光显纳镜的前景，特别关注该技术在神经科学中与相关技术（如机器学习）的结合。

关键词： 荧光成像     衍射极限     纳米级分辨率     神经科学    

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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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penetration enhancers on the nano-structure of stratum corneum model membranes studied using neutron diffraction

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 29-36 doi: 10.1007/s11705-013-1302-0

摘要： Oriented stratum corneum model lipid membranes were used to study the influence of the short chain ceramides (CER)[NP] and [AP] as well as the impact of the lipophilic penetration enhancer molecules oleic acid (OA) and isopropyl myristate (IPM) on the lipid nanostructure. The influence of the enhancer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. H NMR spectroscopy was used to study the impact of the ceramides’ degree of order within the stratum corneum model lipid membranes. It was found that CER[NP] forms two very stable phases with high resistance against temperature increase. Phase B showed unusual hydration behavior as no water uptake of this phase was observed. The H NMR spectroscopic measurements showed that CER[NP] based ternary model system had a higher state of lamellar order in comparison to CER[AP] based lipid matrix. The studies confirmed that the short chain ceramides, particularly CER[NP], have a very high impact on the integrity of the Stratum corneum lipid bilayers. The penetration enhancer OA has not influenced the repeat distance of the model membrane based on CER[AP], and was not able to induce a phase separation in the investigated lipid matrix. However, a disorder and a fluidisation of the model membranes were observed when OA was incorporated. IPM showed the same effect but two phases (assigned as phase A and B) appeared, when IPM was used as penetration enhancer and incorporated into the model membrane. Furthermore, two arrangements of IPM were identified in phase A using deuterated IPM. A model of the nanostructure of the Stratum corneum lipid membranes is presented.

关键词： nano-structure of the stratum corneum     ceramide     penetration enhancer     model membrane     neutron diffraction     2H NMR spectroscopy    

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标题 作者 时间 类型 操作

DyFe11Ti磁结构及其自旋重取向的中子衍射研究

Olivier Isnard, Eder J. Kinast

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

波浪与外壁透空双筒柱的互相作用

滕斌,李玉成,孙路

期刊论文

Application of digital holography to circle flow bed boiler measurement

PU Shiliang, WANG Qinghui, CEN Kefa, Denis Lebrun, REN Kuanfang

期刊论文

Preparation and property of porous hydroxyapatite as an inorganic dispersant used in suspension polymerization

XU Kaqiu, XU Jiale, WANG Yuhong

期刊论文

Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

期刊论文

Synthesis and properties of polybenzazoles containing flexible methylene in backbone

XU Xiaohui, LIU Xiaoyun, ZHOU Chengjun, ZHUANG Qixin, HAN Zhewen

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

LiFePO/C cathode materials synthesized by co-precipitation and microwave heating

XU Yunlong, TAO Lili, MA Hongyan, HUANG Huaqing

期刊论文

Catalysis and deactivation of montmorillonite K10 in the aryl O -glycosylation of glycosyl trichloroacetoimidates

Xiaoliu LI, Xinhao YAN, Zhiwei LI, Hua CHEN, Pingzhu ZHANG,

期刊论文

Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substituted perovskite carrier on the catalyst activities

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

期刊论文

Characterization of chlorine and heavy metals for the potential recycling of bottom ash from municipal solid waste incinerators as cement additives

Boran WU, Dongyang WANG, Xiaoli CHAI, Fumitake TAKAHASHI, Takayuki SHIMAOKA

期刊论文

荧光显纳镜在神经科学中的应用

王杨云逗, 林剑, 张启明, 陈希, 栾海涛, 顾敏

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

penetration enhancers on the nano-structure of stratum corneum model membranes studied using neutron diffraction

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

期刊论文