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Lithium-ion modified cellulose as a water-soluble binder for Li-O battery

《能源前沿（英文）》 2022年 第16卷 第3期   页码 502-508 doi: 10.1007/s11708-021-0750-3

摘要： An environment-friendly, water-soluble, and cellulose based binder (lithium carboxymethyl cellulose, CMC-Li) was successfully synthesized by using Li+ to replace Na+ in the commercial sodium carboxymethyl cellulose (CMC-Na). Li-O2 batteries based on the CMC-Li binder present enhanced discharge specific capacities (11151 mA·h/g at 100 mA/g) and a superior cycling stability (100 cycles at 200 mA/g) compared with those based on the CMC-Na binder. The enhanced performance may originate from the electrochemical stability of the CMC-Li binder and the ion-conductive nature of CMC-Li, which promotes the diffusion of Li+ in the cathode and consequently retards the increase of charge transfer resistance of the cathode during cycling. The results show that the water-soluble CMC-Li binder can be a green substitute for poly(vinylidene fluoride) (PVDF) binder based on organic solvent in the lithium oxygen batteries (LOBs).

关键词： cellulose     binder     specific capacity     cyclabi- lity     lithium-oxygen batteries    

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Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 165-171 doi: 10.15302/J-FASE-2017145

摘要： To determine the main parameters of droplet strike damage and avoid flower injury due to the unsuitable practices during sprinkler irrigation, an indoor experiment of irrigation droplet impact on cyclamen was conducted. The influences of different parameters such as droplet diameter, application intensity, specific power on flower strike damage was analyzed using Image Pro-Plus software to compute strike damage area and define damage level by sense-analysis. The results showed that a damage area of <1% represents a safe irrigation level, 1%–3% slight damage level, 3%–6% moderate damage level, and>6% heavy damage level. Equations of application intensity, specific power with sprinkler irrigation time and flower injury ratio were regressed against parameters which cause impact damages. The results indicated that specific power has a significant correlation with injury, and flower damage area increased as the increasing of the value of specific power for the same irrigation time. Application intensity was also correlated with injury when the droplet diameter was larger than 1 mm. When the duration of sprinkler irrigation was 1, 5 and 10 min, the threshold of impinging damage of application intensity was 25.30, 5.01 and 1.64 mm·h and the specific power was 0.467×10 , 9.340×10 and 3.110×10 W·m . These results provide a reference for determining the suitable values of sprinkler properties in operation design.

关键词： application intensity     damage     floriculture     flowers     specific power     sprinkler irrigation    

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The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1411-9

摘要：

• Actual SAORs was determined using MLVSS and temperature.

关键词： Specific ammonia oxidation rate     Sequencing batch reactor     Biomass     Temperature coefficient     Model simulation    

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比能法在渤海海峡隧道TBM 施工中的应用分析

高攀,邹翀

《中国工程科学》 2013年 第15卷 第12期   页码 73-79

摘要：

拟建的渤海海峡隧道采用隧道掘进机（TBM）施工极具挑战性，其中关键之一就是TBM的掘进速率预测问题。本文将渤海海峡隧道和澳大利亚Clem Jones 隧道进行工程类比，并介绍了比能法在Clem Jones 隧道的应用情况。在Clem Jones 隧道施工过程中，相关研究人员运用比能法对TBM的可掘性进行了分析及预测，从后期的掘进情况来看比能法的预测结果与实际施工吻合得较好。本文在Clem Jones 隧道和渤海海峡隧道对比分析的基础上，认为运用比能法预测TBM的可掘性同样适用于渤海海峡隧道的TBM施工。

关键词： TBM     比能     凿岩速率指数     掘进速率    

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Efficient acetylene/carbon dioxide separation with excellent dynamic capacity and low regeneration energy

《化学科学与工程前沿（英文）》   页码 1616-1622 doi: 10.1007/s11705-022-2183-x

摘要： Adsorptive separation of acetylene/carbon dioxide mixtures by porous materials is an important and challenging task due to their similar sizes and physical properties. Here, remarkable acetylene/carbon dioxide separation featuring a high dynamic breakthrough capacity for acetylene (4.3 mmol·g–1) as well as an ultralow acetylene regeneration energy (29.5 kJ·mol–1) was achieved with the novel TiF62–-pillared material ZU-100 (TIFSIX-bpy-Ni). Construction of a pore structure with abundant TiF62– anion sites and pores with appropriate sizes enabled formation of acetylene clusters through hydrogen bonds and intermolecular interactions, which afforded a high acetylene capacity (8.3 mmol·g–1) and high acetylene/carbon dioxide uptake ratio (1.9) at 298 K and 1 bar. Moreover, the NbO52– anion-pillared material ZU-61 investigated for separation of acetylene/carbon dioxide. In addition, breakthrough experiments were also conducted to further confirm the excellent dynamic acetylene/carbon dioxide separation performance of ZU-100.

关键词： adsorption     acetylene/carbon dioxide separation     dynamic capacity     anion-pillared hybrid material    

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Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

《结构与土木工程前沿（英文）》 2013年 第7卷 第1期   页码 50-54 doi: 10.1007/s11709-013-0186-x

摘要： Granular matter possesses impact-absorbing property due to its energy dissipation character. To investigate the impact-absorbing capacity of granular matter, the discrete element method (DEM) is adopted to simulate the impact of a spherical projectile on to a granular bed. The dynamic responses of the projectile are obtained for both thin and thick granular bed. The penetration depth of the projectile and the first impact peak are investigated with different bed thicknesses and impact velocities. Determining a suitable bed thickness is crucial to the buffering effect of granular matter. The first impact peak is independent of bed thickness when the thickness is larger than the critical thickness.

关键词： granular matter     impact peak     buffer capacity     discrete element method     critical thickness    

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An integrated approach to site-specific management zone delineation

Yuxin MIAO, David J. MULLA, Pierre C. ROBERT

《农业科学与工程前沿（英文）》 2018年 第5卷 第4期   页码 432-441 doi: 10.15302/J-FASE-2018230

摘要：

Dividing fields into a few relatively homogeneous management zones (MZ) is a practical and cost-effective approach to precision agriculture. There are three basic approaches to MZ delineation using soil and/or landscape properties, yield information, and both sources of information. The objective of this study is to propose an integrated approach to delineating site-specific MZ using relative elevation, organic matter, slope, electrical conductivity, yield spatial trend map, and yield temporal stability map (ROSE-YSTTS) and evaluate it against two other approaches using only soil and landscape information (ROSE) or clustering multiple year yield maps (CMYYM). The study was carried out on two no-till corn-soybean rotation fields in eastern Illinois, USA. Two years of nitrogen (N) rate experiments were conducted in Field B to evaluate the delineated MZs for site-specific N management. It was found that in general the ROSE approach was least effective in accounting for crop yield variability (8.0%–9.8%), while the CMYYM approach was least effective in accounting for soil and landscape (8.9%–38.1%), and soil nutrient and pH variability (9.4%–14.5%). The integrated ROSE-YSTTS approach was reasonably effective in accounting for the three sources of variability (38.6%–48.9%, 16.1%–17.3% and 13.2%–18.7% for soil and landscape, nutrient and pH, and yield variability, respectively), being either the best or second best approach. It was also found that the ROSE-YSTTS approach was effective in defining zones with high, medium and low economically optimum N rates. It is concluded that the integrated ROSE-YSTTS approach combining soil, landscape and yield spatial-temporal variability information can overcome the weaknesses of approaches using only soil, landscape or yield information, and is more robust for MZ delineation. It also has the potential for site-specific N management for improved economic returns. More studies are needed to further evaluate their appropriateness for precision N and crop management.

关键词： economically optimum nitrogen rate     fuzzy cluster analysis     precision nitrogen management     site-specific management     soil landscape property     yield map    

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Dynamic simulation of urban water metabolism under water environmental carrying capacity restrictions

Weihua ZENG,Bo WU,Ying CHAI

《环境科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 114-128 doi: 10.1007/s11783-014-0669-6

摘要： A revised concept for urban water metabolism (UWM) is presented in this study to address the inadequacies in current research on UWM and the problems associated with the traditional urban water metabolic process. Feedback loops can be analyzed to increase the water environmental carrying capacity (WECC) of the new urban water metabolism system (UWMS) over that of a traditional UWMS. An analysis of the feedback loops of an UWMS was used to construct a system dynamics (SD) model for the system under a WECC restriction. Water metabolic processes were simulated for different scenarios using the Tongzhou District in Beijing as an example. The results for the newly developed UWM case showed that a water environment of Tongzhou District could support a population of 1.1926 × 10 , an irrigation area of 375.521 km , a livestock of 0.7732 × 10 , and an industrial value added of ¥193.14 × 10 (i.e. about US$28.285× 10 ) in 2020. A sensitivity analysis showed that the WECC could be improved to some extent by constructing new sewage treatment facilities or by expanding the current sewage treatment facilities, using reclaimed water and improving the water circulation system.

关键词： urban water metabolism system (UWMS)     system dynamic simulation     water environmental carrying capacity (WECC)     feedback loops     bilateral control    

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Polypropylene microplastics alter the cadmium adsorption capacity on different soil solid fractions

《环境科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 3-3 doi: 10.1007/s11783-021-1437-z

摘要：

Microplastics (MPs) are widely present in a variety of environmental media and have attracted more and more attention worldwide. However, the effect of MPs on the interaction between heavy metals and soil, especially in soil solid fraction level, is not well understood. In this study, batch experiments were performed to investigate the adsorption characteristics of Cd in bulk soil and three soil solid fractions (i.e. particulate organo matter (POM), organic-mineral compounds (OMC), and mineral) with or without polypropylene (PP) MPs.

关键词： Polypropylene microplastics     Cadmium     Adsorption     POM     OMC     Mineral    

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Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

《结构与土木工程前沿（英文）》   页码 901-914 doi: 10.1007/s11709-023-0915-8

摘要： The integrity and bearing capacity of segment joints in shield tunnels are associated closely with the mechanical properties of the joints. This study focuses on the mechanical characteristics and mechanism of a bolted circumferential joint during the entire bearing process. Simplified analytical algorithms for four stress stages are established to describe the bearing behaviors of the joint under a compressive bending load. A height adjustment coefficient, α, for the outer concrete compression zone is introduced into a simplified analytical model. Factors affecting α are determined, and the degree of influence of these factors is investigated via orthogonal numerical simulations. The numerical results show that α can be specified as approximately 0.2 for most metro shield tunnels in China. Subsequently, a case study is performed to verify the rationality of the simplified theoretical analysis for the segment joint via numerical simulations and experiments. Using the proposed simplified analytical algorithms, a parametric investigation is conducted to discuss the factors affecting the ultimate compressive bending capacity of the joint. The method for optimizing the joint flexural stiffness is clarified. The results of this study can provide a theoretical basis for optimizing the design and prediciting the damage of bolted segment joints in shield tunnels.

关键词： shield tunnel     segment joint     joint structural model     failure mechanism    

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A method to calculate working capacity space of multi-DOF manipulator and the application in excavating

Baochen WEI, Feng GAO

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 109-119 doi: 10.1007/s11465-012-0323-6

摘要：

Working capacity refers to the velocity output and force output of a manipulator. It is usually be represented by output capacity space. In this paper, the method of Linear Programming and a geometric method are proposed to calculate working capacity spaces in different situations. With the consideration of gravity effect of every component, the output force capacity space of heavy duty manipulators is calculated. The results show that the effect of the gravity is a translation of the capacity space. This paper gives a method for the output capacity express especially for heavy duty manipulators. The output capacity space can be helpful to the driving parameters selection. With the consideration of the gravity effect of every component and the friction at the joints, the excavating force capacity space of the heavy-load excavating mechanism is calculated and is represented as a multi-dimensional polytope. The results show that the effect of the gravity and friction is to translational act on the capacity space.

关键词： working capacity     multi-DOF manipulator     capacity polytope     excavating mechanism    

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Foundations bearing capacity subjected to seepage by the kinematic approach of the limit analysis

Mehdi VEISKARAMI, Ghasem HABIBAGAHI

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 446-455 doi: 10.1007/s11709-013-0227-5

摘要： An estimate of the ultimate load on foundations on soil layers subject to groundwater flow has been presented. The kinematic approach of the limit analysis was employed to find the upper-bound limit of the bearing capacity. Both smooth and rough base strip foundations were considered associated with different collapse patterns. Presence of the groundwater flow leads to a non-symmetric collapse pattern, i.e., a weak side and a strong side in two-sided collapse patterns, depending on the direction of the flow. It was found that the bearing capacity has a decreasing trend with increase in the groundwater flow gradient and hence, a reduction factor has been introduced to the third term in the bearing capacity equation as a function of the flow gradient.

关键词： foundation     bearing capacity     limit analysis     numerical computation     plasticity     seepage    

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Analysis on shear capacity of prestressed concrete spatial connections

XUE Weichen, LIU Zhenyong, JIANG Dongsheng

《结构与土木工程前沿（英文）》 2008年 第2卷 第4期   页码 309-317 doi: 10.1007/s11709-008-0052-4

摘要： Based on experimental results of prestressed concrete spatial connections, nonlinear finite element models were established to analyze the shear capacity of spatial connections and parametric studies were performed using ANSYS. It is found that the shear capacity of spatial connection is influenced by joint hoop, beam prestress, column compressive load, and direction of resultant shear force. The parametric studies also indicate that the shear capacity of spatial connection under biaxial cyclic loading is lower than that of corresponding connections under plane loading. A design formula for calculating the shear capacity of spatial connections is proposed based on the parametric studies and verified by the available test results.

关键词： available     direction     nonlinear     capacity     compressive    

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Undrained seismic bearing capacity of strip footing adjacent to a heterogeneous excavation

《结构与土木工程前沿（英文）》 2023年 第17卷 第4期   页码 566-583 doi: 10.1007/s11709-023-0905-x

摘要： The analysis of the bearing capacity of strip footings sited near an excavation is critical in geotechnics. In this study, the effects of the geometrical features of the excavation and the soil strength properties on the seismic bearing capacity of a strip footing resting on an excavation were evaluated using the lower and upper bounds of the finite element limit analysis method. The effects of the setback distance ratio (L/B), excavation height ratio (H/B), soil strength heterogeneity (kB/cu), and horizontal earthquake coefficient (kh) were analyzed. Design charts and tables were produced to clarify the relationship between the undrained seismic bearing capacity and the selected parameters.

关键词： excavation     finite element limit analysis     heterogeneous soil     strip footing     undrained bearing capacity    

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Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1016-1024 doi: 10.1007/s11709-021-0751-7

摘要： This study investigated the use of recycled tire-derived aggregate (TDA) mixed with kaolin as a method of increasing the ultimate bearing capacity ( UBC) of a strip footing. Thirteen 1g physical modeling tests were prepared in a rigid box of 0.6 m × 0.9 m in plan and 0.6 m in height. During sample preparation, 0%, 20%, 40%, or 60% (by weight) of powdery, shredded, small-sized granular (G 1–4 mm) or large-sized granular (G 5–8 mm) TDA was mixed with the kaolin. A strip footing was then placed on the stabilized kaolin and was caused to fail under stress-controlled conditions to determine the UBC. A rigorous 3D finite element analysis was developed in Optum G-3 to determine the UBC values based on the experimental test results. The experimental results showed that, except for the 20% powdery TDA, the TDA showed an increase in the UBC of the strip footing. When kaolin mixed with 20% G (5–8 mm), the UBC showed a threefold increase over that for the unreinforced case. The test with 20% G (1–4 mm) recorded the highest subgrade modulus. It was observed that the UBC calculated using finite element modeling overestimated the experimental UBC by an average of 9%.

关键词： kaolin     physical modeling tests     stabilization     numerical modeling    

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标题 作者 时间 类型 操作

Lithium-ion modified cellulose as a water-soluble binder for Li-O battery

期刊论文

Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

期刊论文

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

期刊论文

比能法在渤海海峡隧道TBM 施工中的应用分析

高攀,邹翀

期刊论文

Efficient acetylene/carbon dioxide separation with excellent dynamic capacity and low regeneration energy

期刊论文

Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

期刊论文

An integrated approach to site-specific management zone delineation

Yuxin MIAO, David J. MULLA, Pierre C. ROBERT

期刊论文

Dynamic simulation of urban water metabolism under water environmental carrying capacity restrictions

Weihua ZENG,Bo WU,Ying CHAI

期刊论文

Polypropylene microplastics alter the cadmium adsorption capacity on different soil solid fractions

期刊论文

Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

期刊论文

A method to calculate working capacity space of multi-DOF manipulator and the application in excavating

Baochen WEI, Feng GAO

期刊论文

Foundations bearing capacity subjected to seepage by the kinematic approach of the limit analysis

Mehdi VEISKARAMI, Ghasem HABIBAGAHI

期刊论文

Analysis on shear capacity of prestressed concrete spatial connections

XUE Weichen, LIU Zhenyong, JIANG Dongsheng

期刊论文

Undrained seismic bearing capacity of strip footing adjacent to a heterogeneous excavation

期刊论文

Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

期刊论文