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底泥污染 1

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重污染支流 1

金属-有机框架，烃类吸附和分离，选择性，稳定性，放大合成 1

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Experimental study on the stratum applicability and mechanisms of bubble–slurry for earth pressure balance

《结构与土木工程前沿（英文）》页码 1387-1399 doi: 10.1007/s11709-023-0005-y

摘要： Soil conditioning is essential for addressing the stratum applicability problem of earth pressure balance (EPB) shields. Under high water pressures, EPB shields spew water and soil when excavating coarse-grained strata. Typically, foam combined with polymers and slurry is used to solve spewing. However, in current techniques, slurry, foam, and the other agents are mixed with soil separately, their synergistic effect is seldom realized. In this study, an anionic surfactant was used to foam in bentonite slurry to form bubble–slurry to maximize the synergy between bubbles and slurry. The slump, volume stability, and permeability test of bubble–slurry-conditioned sand was conducted to examine the conditioning effect, and the stratum applicability of bubble–slurry was determined from the perspective of permeability. It was found that the conditioning effect of bubble–slurry in coarse gravel soil was excellent and could expand the applicability of EPB shields. The main stabilization mechanism of bubble–slurry is that bentonite particles provide a space barrier for bubbles. And three seepage modes of bubble–slurry-conditioned sand were innovatively defined, and the occurrence conditions of the three seepage modes were analyzed according to the permeability coefficient of sand, initial dynamic shear force of bubble–slurry, and hydraulic gradient.

关键词： EPB shield bubble–slurry soil conditioning stability permeability

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On the applicability of different adhesion models in adhesive particulate flows

Guanqing LIU, Shuiqing LI, Qiang YAO,

《能源前沿（英文）》 2010年第4卷第2期页码 280-286 doi: 10.1007/s11708-009-0062-5

摘要： An adhesion map provides quantitative criteria for the appropriate selection of adhesion models applicable to a specific adhesive contact problem of fine particles in complex particulate flows. In this paper, three different general adhesion models are used to construct adhesion maps. The applicable regimes on the adhesion map for different approximate adhesion models are determined according to their underlying limitations. It is found that the choice of general model has limited influence on the structure of a constructed adhesion map. On the contrary, the regime of application for each approximate model is sensitive to the approximation level. A three-dimensional, more intuitive adhesion map based on physical parameters of particles is also built. Finally, recent applications of adhesion models in discrete element method (DEM) investigations of fine-particle flow dynamics are briefly discussed.

关键词： adhesive contact van der Waals force adhesion model adhesion map DEM

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Impact of household transitions on domestic energy consumption and its applicability to urban energy

Benachir MEDJDOUB, Moulay Larbi CHALAL

《工程管理前沿（英文）》 2017年第4卷第2期页码 171-183 doi: 10.15302/J-FEM-2017029

摘要： The household sector consumes roughly 30% of Earth’s energy resources and emits approximately 17% of its carbon dioxide. As such, developing appropriate policies to reduce the CO emissions, which are associated with the world’s rapidly growing urban population, is a high priority. This, in turn, will enable the creation of cities that respect the natural environment and the well-being of future generations. However, most of the existing expertise focuses on enhancing the thermal quality of buildings through building physics while few studies address the social and behavioral aspects. In fact, focusing on these aspects should be more prominent, as they cause between 4% and 30% of variation in domestic energy consumption. Premised on that, the aim of this study was to investigate the effect in the context of the UK of household transitions on household energy consumption patterns. To achieve this, we applied statistical procedures (e.g., logistic regression) to official panel survey data comprising more than 5500 households in the UK tracked annually over the course of 18 years. This helped in predicting future transition patterns for different household types for the next 10 to 15 years. Furthermore, it enabled us to study the relationship between the predicted patterns and the household energy usage for both gas and electricity. The findings indicate that the life cycle transitions of a household significantly influence its domestic energy usage. However, this effect is mostly positive in direction and weak in magnitude. Finally, we present our developed urban energy model “EvoEnergy” to demonstrate the importance of incorporating such a concept in energy forecasting for effective sustainable energy decision-making.

关键词： urban energy planning household transitions smart cities energy forecasting household projection serious gaming

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湖泊底泥污染控制技术及其适用性探讨

胡小贞,金相灿,卢少勇,储昭升

《中国工程科学》 2009年第11卷第9期页码 28-33

摘要：

对目前国内外应用较多的三类底泥污染控制技术，即环保疏浚技术、原位覆盖技术、原位钝化技术的技术特点、关键技术内容、可能产生的主要环境问题及其应用现状进行了详细分析。在各项技术的优缺点、费用效益比较的基础上，提出环保疏浚技术适用于大面积重污染湖区或河口底泥污染的控制，原位覆盖技术适用于中深水湖泊、海域或河流底泥污染的控制，原位钝化技术适合于风浪扰动不大、非饮用水源地功能湖泊底泥污染的控制。并对三项技术在我国湖泊底泥污染控制领域的应用前景进行了展望。

关键词：湖泊底泥污染控制技术适用性

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Simplified analytical solution for free vibration characteristics of Hardfill dam

XIAO Wei, HE Yunlong, ZHANG Yanfeng

《结构与土木工程前沿（英文）》 2008年第2卷第3期页码 219-225 doi: 10.1007/s11709-008-0037-3

摘要： Formulas for computing natural frequencies and modes of Hardfill dams are derived based on one-dimensional shear wedge theory, in which the influences of the upstream concrete face and hydrodynamic pressure of water on the dams’ natural frequencies and modes are discussed. Furthermore, the seismic responses of Hardfill dams are calculated using response spectrum method. An example is analyzed to compare the differences of natural frequencies and modes between shear wedge method and FEM. Then the applicability and accuracy of shear wedge method to analyze free vibration characteristics of Hardfill dams are proven.

关键词： upstream concrete hydrodynamic pressure vibration one-dimensional applicability

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Applicability of the Arrhenius model for Ammonia Oxidizing Bacteria subjected to temperature time gradients

Alberto MANNUCCI,Giulio MUNZ,Gualtiero MORI,Claudio LUBELLO,Jan A. OLESZKIEWICZ

《环境科学与工程前沿（英文）》 2015年第9卷第6期页码 988-994 doi: 10.1007/s11783-014-0751-0

摘要： The aim of this work is to identify the range of applicability of Arrhenius type temperature dependence for Ammonia Oxidizing Bacteria (AOB) subjected to temperature time gradients through continuous titrimetric tests. An innovative online differential titrimetric technique was used to continuously monitor the maximum biologic ammonia oxidation rate of the biomass selected in a pilot scale membrane bioreactor, as a function of temperature time gradients. The monitoring technique is based on the measurement of alkalinity and hydrogen peroxide consumption rates in two parallel reactors operated in non-limiting substrate conditions for AOB; both reactors were continuously fed with mixed liquor and in one of them AOB were inhibited with allylthiourea. The effects of temperature decrease rates in the range 1 to 4°C·h were evaluated by controlling the titrimetric reactor in the temperature range 10°C–20°C. The dependence of growth kinetics on temperature time gradients and the range of applicability of Arrhenius model for temperature dependency of AOB growth kinetics were assessed. The Arrhenius model was found to be accurate only with temperature gradients lower than 2°C·h . The estimated Arrhenius coefficients ( ) were shown to increase from 1.07 to 1.6 when the temperature decrease rate reached 4°C·h .

关键词： nitrification rate temperature effect continuous titrimetric tests time-gradient temperature variations Ammonia Oxidizing Bacteria (AOB)

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Applicability of high dimensional model representation correlations for ignition delay times of n-heptane

Wang LIU, Jiabo ZHANG, Zhen HUANG, Dong HAN

《能源前沿（英文）》 2019年第13卷第2期页码 367-376 doi: 10.1007/s11708-018-0584-9

摘要： It is difficult to predict the ignition delay times for fuels with the two-stage ignition tendency because of the existence of the nonlinear negative temperature coefficient (NTC) phenomenon at low temperature regimes. In this paper, the random sampling-high dimensional model representation (RS-HDMR) methods were employed to predict the ignition delay times of n-heptane/air mixtures, which exhibits the NTC phenomenon, over a range of initial conditions. A detailed n-heptane chemical mechanism was used to calculate the fuel ignition delay times in the adiabatic constant-pressure system, and two HDMR correlations, the global correlation and the stepwise correlations, were then constructed. Besides, the ignition delay times predicted by both types of correlations were validated against those calculated using the detailed chemical mechanism. The results showed that both correlations had a satisfactory prediction accuracy in general for the ignition delay times of the n-heptane/air mixtures and the stepwise correlations exhibited a better performance than the global correlation in each subdomain. Therefore, it is concluded that HDMR correlations are capable of predicting the ignition delay times for fuels with two-stage ignition behaviors at low-to-intermediate temperature conditions.

关键词： ignition delay random sampling high dimensional model representation n-heptane fuel kinetics

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浑河沈抚区域重污染支流河治理技术研究

彭剑峰,宋永会,高红杰,任兆勇,李蕊,于会彬

《中国工程科学》 2013年第15卷第3期页码 103-106

摘要：

针对浑河沈阳—抚顺（沈抚）区域重污染支流污染来源及水质变化特点，优化筛选出潮汐流人工湿地强化脱氮技术、多层组合生物浮岛净化技术，以及傍河藻类塘与水生植物塘联用等支流河修复技术；分析了各项技术的基本原理、处理效果，提出了最佳工艺运行参数，验证了技术在示范工程中的应用效果。结果表明，相关技术对于北方地区重污染支流具有较好的治理效果，具有较高的推广价值。

关键词：重污染支流沈抚区域潮汐流湿地适用性

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天然气提质过程中可有效回收丙烷和乙烷的高工业应用潜力金属有机框架材料 Article

咸士凯, 彭俊杰, Haardik Pandey, Timo Thonhauser, 王浩, 李静

《工程（英文）》 2023年第23卷第4期页码 56-63 doi: 10.1016/j.eng.2022.07.017

摘要：

开发具有高吸收和选择性的高效吸附剂用于从天然气中分离和回收C₂H₆和C₃H₈是一项重要但具有挑战性的任务。在这项工作中，我们证明了高表面极性和合适孔径是协同提高分离性能的两个关键因素，例如，金属有机框架（MOF）-303 和MIL-160（MIL：拉瓦锡材料研究所）都具有一维（1D）开放通道，其具有高密度杂原子和所需的孔径（5~7 Å）。值得注意的是，MOF-303 在298 K和5 kPa 下对C3H8的吸收高达3.38 mmol∙g⁻¹，C₃H₈/CH₄ (5:85, V/V)理想吸附溶液理论（IAST）选择性为5114，在所有已报道的MOF中创下新高。此外，MOF-303 也显示出很高的C2H6吸收能力（在10 kPa 时）和C₂H₆/CH₄(10:85, V/V)选择性，分别达到1.59 mmol∙g⁻¹和26。与MOF-303 相比，MIL-160 的孔径更大，1D通道内杂原子密度更低，因此其具有明显较低的吸收和选择性，但其值超过了大多数报道的MOF。密度泛函理论（DFT）的计算结果表明，高表面极性和合适的孔径能协同增强框架对C₃H₈和C₂H₆的亲和力，从而产生了对C₃H₈和C₂H₆的高负载能力和选择性。在95%的相对湿度（RH）下暴露一个月后，两种MOF均具有显著的湿度稳定性，且结构没有变化。此外，这两种化合物的合成都可以很容易地通过一锅反应来放大规模，从而获得约5 g 的高结晶度样品。最后，通过三元突破性实验、再生试验和循环评价，证明了MOF-303 和MIL-160 作为先进的吸附剂在高效分离C₃H₈/C₂H₆/CH₄方面的巨大潜力。其优异的分离性能、高稳定性、低成本和良好的可扩展性，是天然气净化和回收C₂H₆和C₃H₈的理想吸附剂。