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二氧化硅 1

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偏振模色散（PMD） 1

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原子力显微镜 1

归零码（RZ） 1

木质素 1

超构表面天线；色散调控；复合左右手色散特性；导波；表面波；宽带；低剖面 1

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Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 503-509 doi: 10.1007/s11783-013-0540-1

摘要： A mathematical model for the transport of Ce(IV) from hydrochloric acid solutions through dispersion flat combined liquid membrane (DFCLM) with contain 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (P507) as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick’s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce(IV) and the carrier to take place only at the solvent–aqueous interfaces. Model concentration profiles are obtained for the Ce(IV), from which extraction velocities are predicted. The experimental and simulated Ce(IV) extractions showed similar tendencies for a high Ce(IV) concentration and acidity case.The model results indicate that high initial Ce(IV) concentrations and acidity both have detrimental effects on Ce(IV) extraction and stripping. The diffusion coefficient of Ce(IV) in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10 m ·s and 31.2 μm, respectively. The results are in good agreement with experimental results.

关键词： Dispersion flat combined liquid membrane (DFCLM)     dispersion phase     feed phase     2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester     Ce (IV)    

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Development of oxide dispersion strengthened ferritic steels with and without aluminum

Jae Hoon LEE

《能源前沿（英文）》 2012年 第6卷 第1期   页码 29-34 doi: 10.1007/s11708-012-0178-x

摘要： Pure Fe, Cr, Al, Ti elemental powders and pre-alloyed Y O powder were processed by high energy mechanical milling. The compositions of the mixed powders are designed as Fe-18Cr-0.2Ti-0.35Y O and Fe-18Cr-5Al-0.2Ti-0.35Y O in weight percent. The as-milled powders were consolidated by hot extrusion at 1423 K. The dispersed oxide particles were identified to be titania+ yttria for Al-free oxide dispersion strengthened (ODS) steel and alumina+ yttria for Al-added ODS steel, respectively. The ultimate tensile strength of Al-free ODS steel was higher than that of Al-added ODS steel over the temperature range of 298–973 K, because of the difference in number density and size of thermally stable oxide particles dispersed in both steel matrices. The strength in the longitudinal direction was lower than that in the transverse direction, probably due to anisotropy of the microstructure with elongated grains in the hot-extrusion direction for the 18%Cr-ODS steels with and without 5%Al.

关键词： oxide dispersion strengthened (ODS) steel     milling     extrusion     aluminum     yttria    

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TiO@palygorskite composite for the efficient remediation of oil spills via a dispersion-photodegradation

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1365-3

摘要：

• A novel and multi-functional clay-based oil spill remediation system was constructed.

关键词： Palygorskite     TiO2     Pickering emulsion     Oil spill     Dispersion     Photodegradation    

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Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive

《化学科学与工程前沿（英文）》   页码 1623-1631 doi: 10.1007/s11705-022-2202-y

摘要： The number of active components and their dispersion degree are two key factors affecting the performance of adsorbents. Here, we report a simple but efficient strategy for dispersing active components by using a confined space, which is formed by mesoporous silica walls and templates in the as-prepared SBA-15 (AS). Such a confined space does not exist in the conventional support, calcined SBA-15, which does not contain a template. The Cu and Zn precursors were introduced to the confined space in the AS and were converted to CuO and ZnO during calcination, during which the template was also removed. The results show that up to 5 mmol·g–1 of CuO and ZnO can be well dispersed; however, severe aggregation of both oxides takes place in the sample derived from the calcined SBA-15 with the same loading. Confined space in the AS and the strong interactions caused by the abundant hydroxyl groups are responsible for the dispersion of CuO and ZnO. The bimetallic materials were employed for the adsorptive separation of propene and propane. The samples prepared from the as-prepared SBA-15 showed superior performance to their counterparts from the calcined SBA-15 in terms of both adsorption capacity of propene and selectivity for propene/propane.

关键词： bimetallic adsorbents     confined space     mesoporous silica     propene/propane separation    

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AMMONIA DISPERSION FROM MULTI-FLOOR VERSUS STANDARD SINGLE-FLOOR PIG PRODUCTION FACILITIES BASED ON COMPUTATIONAL

《农业科学与工程前沿（英文）》 2023年 第10卷 第3期   页码 374-389 doi: 10.15302/J-FASE-2023501

摘要：

● NH3 dispersion from a multi-floor pig building was compared to a single-floor building.

关键词： pig building     computational fluid dynamics     ammonia     dispersion    

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Breaking the Ni loading-reducibility-dispersion dependence achieved by solid-state co-grinding

《化学科学与工程前沿（英文）》 2024年 第18卷 第12期 doi: 10.1007/s11705-024-2499-9

摘要： The loading-dispersion-reducibility dependence has always been one of the most critical issues in the development of high-performance supported metal catalysts. Herein, up to 40 wt % NiO over ordered mesoporous alumina (OMA) was prepared by co-grinding the hybrid of template-containing OMA and Ni(NO3)2·6H2O. Characterization results confirmed that the OMA mesostructure was still preserved even after loading NiO at a content as high as 40 wt %. More importantly, the reduction extent, dispersion, and average particle size of the Ni/OMA catalysts were maintained at ≥ 91.0%, ~13.5%, and ~4.0–5.0 nm, respectively, when the NiO loading was increased from 20 to 40 wt %. The catalysts were evaluated for the CO methanation as a model reaction, and the similarly high turnover frequency of 24.0 h–1 was achieved at 300 °C for all of the Ni/OMA catalysts. For the catalyst with the highest NiO loading of 40 wt % (40Ni/OMA), the low-temperature activity at 300 °C indexed by the space-time yield of methane (over 325.8 molCH4⋅kgcat−1⋅h−1) was achieved, while the catalyst was operated without an observable deactivation for a time on stream of 120 h under severe reaction conditions of 600 °C and a very high gas hourly space velocity of 240000 mL·g–1·h–1. With these significant results, this work paves the way for a rational and controllable design of supported Ni catalysts by breaking the loading-dispersion-reducibility dependence and stabilizing Ni nanoparticles under harsh reaction conditions.

关键词： Ni-supported catalyst     solid-state grinding     metal-support interactions     high Ni loading     high dispersion     CO methanation    

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Composition, dispersion, and health risks of bioaerosols in wastewater treatment plants: A review

Yunping Han, Lin Li, Ying Wang, Jiawei Ma, Pengyu Li, Chao Han, Junxin Liu

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1330-1

摘要： Abstract • Bioaerosols are produced in the process of wastewater biological treatment. • The concentration of bioaerosol indoor is higher than outdoor. • Bioaerosols contain large amounts of potentially pathogenic biomass and chemicals. • Inhalation is the main route of exposure of bioaerosol. • Both the workers and the surrounding residents will be affected by the bioaerosol. Bioaerosols are defined as airborne particles (0.05–100 mm in size) of biological origin. They are considered potentially harmful to human health as they can contain pathogens such as bacteria, fungi, and viruses. This review summarizes the most recent research on the health risks of bioaerosols emitted from wastewater treatment plants (WWTPs) in order to improve the control of such bioaerosols. The concentration and size distribution of WWTP bioaerosols; their major emission sources, composition, and health risks; and considerations for future research are discussed. The major themes and findings in the literature are as follows: the major emission sources of WWTP bioaerosols include screen rooms, sludge-dewatering rooms, and aeration tanks; the bioaerosol concentrations in screen and sludge-dewatering rooms are higher than those outdoors. WWTP bioaerosols contain a variety of potentially pathogenic bacteria, fungi, antibiotic resistance genes, viruses, endotoxins, and toxic metal(loid)s. These potentially pathogenic substances spread with the bioaerosols, thereby posing health risks to workers and residents in and around the WWTP. Inhalation has been identified as the main exposure route, and children are at a higher risk of this than adults. Future studies should identify emerging contaminants, establish health risk assessments, and develop prevention and control systems.

关键词： Wastewater treatment plant     Bioaerosols     Pathogen     Dispersion     Risk assessment    

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Comparison of the performance of traditional advection-dispersion equation and mobile-immobile model

Haizhu HU,Xiaomin MAO

《农业科学与工程前沿（英文）》 2016年 第3卷 第3期   页码 241-248 doi: 10.15302/J-FASE-2016108

摘要： The traditional advection-dispersion equation (ADE) and the mobile-immobile model (MIM) are widely used to describe solute transport in heterogeneous porous media. However, the fitness of the two models is case-dependent. In this paper, the transport of conservative, adsorbing and degradable solutes through a 1 m heterogeneous soil column under steady flow condition was simulated by ADE and MIM, and sensitivity analysis was conducted. Results show that MIM tends to prolong the breakthrough process and decrease peak concentration for all three solutes, and tailing and skewness are more pronounced with increasing dispersivity. Breakthrough curves of the adsorbing solute simulated by MIM are less sensitive to the retardation factor compared with the results simulated by ADE. The breakthrough curves of degradable solute obtained by MIM and ADE nearly overlap with a high degradation rate coefficient, indicating that MIM and ADE perform similarly for simulating degradable solute transport when biochemical degradation prevails over the mass exchange between mobile and immobile zones. The results suggest that the physical significance of dispersivity should be carefully considered when MIM is applied to simulate the degradable solute transport and/or ADE is applied to simulate the adsorbing solute transport in highly dispersive soils.

关键词： solute transport     advection dispersion equation (ADE)     mobile-immobile model (MIM)     conservative solute     adsorbing solute     degradable solute     PHREEQC-2    

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Dispersion of a novel phenolic rigid organic filler in isotactic polypropylene matrix by solution-mixing

Dongming QI, Xiaoli ZHAO, Zhijie CHEN, Peng HUANG, Jun CAO

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 395-402 doi: 10.1007/s11705-012-1269-2

摘要： A novel phenolic rigid organic filler (named KD) with a high melting point was dispersed in an isotactic polypropylene (iPP) matrix by solution-mixing and/or melt-mixing. A series of KD/iPP blends was prepared with or without addition of maleic anhydride-grafted polypropylene (MAPP) as a compatibilizer. Influences of MAPP and mixing methods on the filler dispersion were studied using polaried optical microscope (POM), scanning electron microscope (SEM) and tensile test. The filler particles are always inclined to form large irregular aggregates in the iPP matrix due to their significant differences in polarity and solubility in solvent. However, an iPP/MAPP/KD (PMK) blend containing filler particles with a quasi-spherical shape (~97.8 nm in diameter) and narrow particle size distribution (polydispersity index= 1.076) was successfully prepared by incorporating MAPP to reduce the interfacial tension and surface free energy between the dispersion phase and the continuous phase, and adopting a spray-drying method after solution-mixing to suppress the increase of the size of the dispersed phase during the removal of solvent.

关键词： dispersion     rigid organic filler     isotactic polypropylene     mixing    

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On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要： Based on monolayer dispersion theory, Co3O4/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co3O4 can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O2–) and acid sites are crucial for the reaction, which can adsorb and activate NOx and NH3 reactants effectively. Below the monolayer dispersion threshold, Co3O4 is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co3O4 above the capacity is harmful to the reaction performance. 4% Co3O4/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O2– species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co3O4/ZSM-5 catalyst can be prepared by loading the capacity amount of Co3O4 onto HZSM-5 support.

关键词： Co3O4/ZSM-5     NOx-SCR by NH3     monolayer dispersion threshold effect     surface acid sites     surface active O2– anions    

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Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 224-231 doi: 10.1007/s11705-014-1447-5

摘要： CuCl supported on molecular sieves has attracted increasing attention in catalyzing oxidative carbonylation of ethanol to diethyl carbonate. Mesoporous MCM-41 has been widely used as catalyst support due to its large surface area and well defined mesoporous structure. Considering its intrinsic weak acidity, MCM-41 was modified by a simple impregnation method to incorporate Al. The incorporation of Al components resulted in the high dispersion of Cu species and the increase of acid sites without changing the mesoporous structure of MCM-41, and thus enhanceed the catalytic activity of CuCl/MCM-41for diethyl carbonate synthesis.

关键词： MCM-41     acidity     oxidative carbonylation     diethyl carbonate    

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Performance enhancement of partially shaded solar PV array using novel shade dispersion technique

Namani RAKESH,T. Venkata MADHAVARAM

《能源前沿（英文）》 2016年 第10卷 第2期   页码 227-239 doi: 10.1007/s11708-016-0405-y

摘要： Solar photo voltaic array (SPVA) generates a smaller amount of power than the standard rating of the panel due to the partial shading effect. Since the modules of the arrays receive different solar irradiations, the P-V characteristics of photovoltaic (PV) arrays contain multiple peaks or local peaks. This paper presents an innovative method (magic square) in order to increase the generated power by configuring the modules of a shaded photovoltaic array. In this approach, the physical location of the modules in the total cross tied (TCT) connected in the solar PV array is rearranged based on the magic square arrangement pattern. This connection is done without altering any electrical configurations of the modules in the PV array. This method can distribute the shading effect over the entire PV array, without concentrating on any row of modules and can achieve global peaks. For different types of shading patterns, the output power of the solar PV array with the proposed magic square configuration is compared with the traditional configurations and the performance is calculated. This paper presents a new reconfiguration technique for solar PV arrays, which increases the PV power under different shading conditions. The proposed technique facilitates the distribution of the effect of shading over the entire array, thereby, reducing the mismatch losses caused by partial shading. The theoretical calculations are tested through simulations in Matlab/Simulink to validate the results. A comparison of power loss for different types of topologies under different types of shading patterns for a 4 × 4 array is also explained.

关键词： photovoltaic cells     mismatch loss     shading patterns     partial shading     magic square     power enhancement     global peaks and total cross tied (TCT)    

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偏振模色散对高速光码的影响

饶敏,孙小菡,张明德

《中国工程科学》 2002年 第4卷 第11期   页码 67-70

摘要：

研究一阶、二阶偏振模色散（PMD）对10 Gb/s和40 Gb/s的光传输系统性能的影响，考虑PMD的统计特性，基于基本偏振态（PSP）理论数值模拟了非归零码（NRZ）和归零码（RZ）在传输过程中产生的脉冲畸变以及系统Q值的变化。结果表明，传输速率越高PMD对系统性能的影响越显著，二阶PMD也将不可忽略。另外，RZ码传输性能明显优于NRZ码并且可通过预啁啾进行改善。

关键词： 偏振模色散（PMD）     非归零码（NRZ）     归零码（RZ）     频率啁啾    

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基于低色散材料的高效宽带消色差微透镜设计 Article

Xueqian Wang,Chuanbao Liu,Feilou Wang,Weijia Luo,Chengdong Tao,Yuxuan Hou,Lijie Qiao,Ji Zhou,Jingbo Sun,Yang Bai,

《工程（英文）》 2024年 第38卷 第7期   页码 194-200 doi: 10.1016/j.eng.2023.08.023

摘要：

Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultra-compact configuration; however, they suffer from complex fabrication processes and low focusing efficiency. In this study, we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion, an adequately designed convex surface, and a thickness profile distribution. By taking into account the absolute chromatic aberration, relative focal length shift (FLS), and numerical aperture (NA), microlens with a certain focal length can be realized through our realized map of geometric features. Accordingly, the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam, and precise surface profiles were obtained. The fabricated microlenses exhibited a high average focusing efficiency of 65% at visible wavelengths of 410–680 nm and excellent achromatic capability via white light imaging. Moreover, the design exhibited the advantages of being polarization-insensitive and near-diffraction-limited. These results demonstrate the effectiveness of our proposed achromatic microlens design approach, which expands the prospects of miniaturized optics such as virtual and augmented reality, ultracompact microscopes, and biological endoscopy.

关键词： Broadband achromatic focusing     Metamaterials     Low dispersion materials     Visible wavelength     Microlenses    

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基于色散可调超构表面的宽带低剖面天线研究综述 Review Articles

Wei E. I. LIU, Zhi Ning CHEN, Xianming QING

《信息与电子工程前沿（英文）》 2020年 第21卷 第1期   页码 27-38 doi: 10.1631/FITEE.1900473

摘要： 超构表面支持传播导波和表面波，并表现出新颖的色散特性。通过调控其独特的色散特性、设置特殊的边界条件以及选用合适的激励机制，低剖面的超构表面天线也能激励起多个邻近的谐振模式以实现宽带定向辐射。本文首先介绍3类典型宽带低剖面色散可调超构表面天线及其工作原理，接着详细综述色散可调超构表面天线技术的研究进展，重点讨论小型化、圆极化、波束扫描等应用设计。这种新近发展的色散可调超构表面技术，不仅能为宽带低剖面天线设计提供解决方案，更显示其在新型天线技术研发中的巨大潜力。

关键词： 超构表面天线；色散调控；复合左右手色散特性；导波；表面波；宽带；低剖面    

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标题 作者 时间 类型 操作

Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

期刊论文

Development of oxide dispersion strengthened ferritic steels with and without aluminum

Jae Hoon LEE

期刊论文

TiO@palygorskite composite for the efficient remediation of oil spills via a dispersion-photodegradation

期刊论文

Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive

期刊论文

AMMONIA DISPERSION FROM MULTI-FLOOR VERSUS STANDARD SINGLE-FLOOR PIG PRODUCTION FACILITIES BASED ON COMPUTATIONAL

期刊论文

Breaking the Ni loading-reducibility-dispersion dependence achieved by solid-state co-grinding

期刊论文

Composition, dispersion, and health risks of bioaerosols in wastewater treatment plants: A review

Yunping Han, Lin Li, Ying Wang, Jiawei Ma, Pengyu Li, Chao Han, Junxin Liu

期刊论文

Comparison of the performance of traditional advection-dispersion equation and mobile-immobile model

Haizhu HU,Xiaomin MAO

期刊论文

Dispersion of a novel phenolic rigid organic filler in isotactic polypropylene matrix by solution-mixing

Dongming QI, Xiaoli ZHAO, Zhijie CHEN, Peng HUANG, Jun CAO

期刊论文

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

期刊论文

Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

期刊论文

Performance enhancement of partially shaded solar PV array using novel shade dispersion technique

Namani RAKESH,T. Venkata MADHAVARAM

期刊论文

偏振模色散对高速光码的影响

饶敏,孙小菡,张明德

期刊论文

基于低色散材料的高效宽带消色差微透镜设计

Xueqian Wang,Chuanbao Liu,Feilou Wang,Weijia Luo,Chengdong Tao,Yuxuan Hou,Lijie Qiao,Ji Zhou,Jingbo Sun,Yang Bai,

期刊论文

基于色散可调超构表面的宽带低剖面天线研究综述

Wei E. I. LIU, Zhi Ning CHEN, Xianming QING

期刊论文