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Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 727-741 doi: 10.1007/s11709-021-0730-z

摘要： The sliding forms of weak sloped and horizontal subgrades during the sliding process differ. In addition, the sliding form of weakly sloped subgrades exhibits considerable slippage and asymmetry. The accuracy of traditional slice methods for computing the stability safety factor of weakly sloped subgrades is insufficient for a subgrade design. In this study, a novel modified Bishop method was developed to improve the accuracy of the stability safety factor for different inclination angles. The instability mechanism of the weakly sloped subgrade was considered in the proposed method using the “influential force” and “additional force” concepts. The “additional force” reflected the weight effect of the embankment fill, whereas the “influential force” reflected the effect of the potential energy difference. Numerical simulations and experimental tests were conducted to evaluate the advantages of the proposed modified Bishop method. Compared with the traditional slice method, the error between the proposed method and the exact value is less than 32.3% in calculating the safety factor.

关键词： weakly sloped subgrade     stability analysis     additional force     influential force     modified Bishop method    

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A modified pulse charging method for lithium-ion batteries by considering stress evolution, charging

Yanfei ZHAO, Bo LU, Yicheng SONG, Junqian ZHANG

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 294-302 doi: 10.1007/s11709-018-0460-z

摘要： The stress evolution, total charging time and capacity utilization of pulse charging (PC) method are investigated in this paper. It is found that compared to the conventional constant current (CC) charging method, the PC method can accelerate the charging process but will inevitably cause an increase in stress and a decrease in capacity. The charging speed for PC method can be estimated by the mean current. By introducing stress control, a modified PC method called the PCCC method, which starts with a PC operation followed by a CC operation, is proposed. The PCCC method not only can accelerate charging process but also can avoid the stress raising and capacity loss occurring in the PC method. Furthermore, the optimal pulsed current density and switch time in the PCCC method is also discussed.

关键词： fast charging method     pulse charging     stress evolution     charging time     capacity utilization    

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Comprehensive evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHPmethod and Cs dating

ZHANG Yan, GAO Xiang, ZHONG Zhenyu, PENG Buzhuo, DENG Xihai

《环境科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 370-379 doi: 10.1007/s11783-008-0054-4

摘要： Through the use of general sampling and measurement by Cs dating, problems regarding the absence of monitoring data can easily be resolved. Further, weighted values need to be determined while Environment Quality Comprehensive Index (EQCI) is commonly used as applied in environmental quality comprehensive evaluation. In order to overcome the subjectivity in determining weights, the modified Analytical Hierarchy Process (AHP) method was designed. The modified AHP method involved the following key procedures: First, the parameters and were calculated based on the monitoring data; second, the factors were put in order according to the symbol and value of and ; third, the continuous odd integers, which represented the importance of factors, were given to factors according to their seating order; and, fourth, the factor weights were determined from the pair-wise comparison matrix calculated by the ratio of the given odd integers. Therefore, the weights were completely based on the monitoring data. In the present study, the comprehensive quality of sediments in five sections of Lake Dianchi were evaluated and the results indicated that the current contamination of sediments in each lake section is much more serious than at any other time in history.

关键词： Dianchi     Analytical Hierarchy     monitoring     modified Analytical     importance    

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Model reduction of contact dynamics simulation using a modified Lyapunov balancing method

Jianxun LIANG, Ou MA, Caishan LIU

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 383-391 doi: 10.1007/s11465-011-0244-9

摘要：

Finite element models are often used to simulate impact and contact dynamics responses of multibody dynamical systems. However, such a simulation remains very inefficient because very small integration time step must be used when solving the involved differential equations, especially when the involved contact stiffness is high. Although many model reduction techniques have been available to improve the efficiency of finite element based simulations, these techniques cannot be readily applied to contact dynamics simulations due to the high nonlinearity of the contact dynamics models. This paper presents a model reduction approach for finite-element based multibody contact dynamics simulation, based on a modified Lyapunov balanced truncation method. An example is presented to demonstrate that, by applying the model reduction the simulation process is significantly speeded up and the resulting error is bounded within an acceptable level. The performance of the method with respect to some influential factors such as element size, shape and contact stiffness is also investigated.

关键词： contact dynamics     dynamic simulation     model reduction     finite element method    

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Upgrade of three municipal wastewater treatment lagoons using a high surface area media

BISHOP, Fuzhi LI

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 288-293 doi: 10.1007/s11783-011-0280-z

摘要： Lagoon-based municipal wastewater treatment plants (WWTPs) are facing difficulties meeting the needs of rapid population growth as well as the more stringent requirements of discharge permits. Three municipal WWTPs were modified using a high surface area media with upgraded fine-bubble aeration systems. Performance data collected showed very promising results in terms of five-day biochemical oxygen demand (BOD ), ammonia (NH ) and total suspended solids (TSS) removal. Two-year average ammonia effluents were 4.1 mg·L for Columbia WWTP, 4 mg·L for Larchmont WWTP and 2.1 mg·L for Laurelville WWTP, respectively. Two- year average BOD effluents were 6.8, 4.9 and 2.7 mg·L , and TSS effluents were 15.0, 9.6 and 7.5 mg·L . The systems also showed low fecal coliform (FC) levels in their effluents.

关键词： wastewater lagoons     wastewater biological treatment     ammonia removal     high surface area media     fine bubble aeration    

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基于修正Anderson 模型的冲击载荷下地基振动响应预测方法

房波

《中国工程科学》 2014年 第16卷 第11期   页码 96-102

摘要：

提出了一个预测潜在冲击载荷下振动效应的理论模型与现场实测相结合的综合预测方法。通过一系列具有针对性的室外重锤冲击振动试验，以及现场实测数据对Anderson 模型进行了验证并修正，然后利用修正的Anderson 模型预测冲击荷载的振动效应。将预测结果和现场试验结果进行对比分析，结果表明：预测结果与实测结果吻合较好。

关键词： 预测方法     冲击载荷     振动效应     Anderson 模型    

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一种工业过程时变参数估计新算法——修正目标函数法

张承慧

《中国工程科学》 2001年 第3卷 第11期   页码 54-59

摘要：

针对某些工业过程控制参数高度时变的特点和LS拟合算法存在病态估计的现象，提出了一类基于 修正目标函数的时变参数估计算法，并给出递推辅助变量算法。此类算法不仅具有较强的实时跟踪能力和较高 的估计精度，而且能克服病态估计，摆脱了伪随机信号在工程中带来的麻烦。新算法没有增加计算量，非常适 合于工程应用，仿真及实际应用结果都证明新算法是有效的。文中给出了有关新算法的定理及其证明。

关键词： 参数估计     计算方法     LS算法     时变系统     工业生产    

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Modified pretreatment method for total microbial DNA extraction from contaminated river sediment

Yun FANG,Meiying XU,Xingjuan CHEN,Guoping SUN,Jun GUO,Weimin WU,Xueduan LIU

《环境科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 444-452 doi: 10.1007/s11783-014-0679-4

摘要： Extraction of high-quality microbial DNA from contaminated environmental samples is an essential step in microbial ecological study. Based on previously published methods for soil and sediment samples, a modified pretreatment method was developed for extracting microbial DNA from heavily contaminated river sediment samples via selection of optimal pretreatment parameters (i.e., reagent solution, reaction duration, and temperature). The pretreatment procedure involves washing the river sediment sample for three times with a solution containing 0.1 mol·L ethylene diamine tetraacetic acid (EDTA), 0.1 mol·L Tris (pH 8.0), 1.5 mol·L NaCl, 0.1 mol·L NaH PO , and Na HPO at 65°C with 180 r·min for 15 min to remove humic materials and heavy metals prior to the employment of standard DNA extraction procedures. We compared the results of standard procedure DNA extraction following pretreatment, without pretreatment, and with using a commercial PowerSoil DNA Isolation Kit. The results indicated that the pretreatment significantly improved the DNA quality based on DNA yield, DNA fragment length, and determination of prokaryotic diversity. Prokaryotic diversity exhibited in the DNA with the pretreatment was also considerably higher than that extracted with the PowerSoil DNA Isolation Kit only. The pretreatment method worked well even with a small amount of sediment sample (0.25 g or even lower). The method provides a novel, simple, cost-effective tool for DNA extraction for microbial community analysis in environmental monitoring and remediation processes.

关键词： river sediment     DNA extraction     contaminant     pretreatment     microbial community    

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Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

《农业科学与工程前沿（英文）》 2020年 第7卷 第2期   页码 188-203 doi: 10.15302/J-FASE-2019307

摘要：

Precision genetics and breeding have the potential to meet the agricultural needs and goals of the world in the 21st century. These needs include increasing the efficiency of production of animals and improving their products with minimal impact on the environment. The USA is the major innovator in genomic science and the acknowledged leader in formulating policies to regulate genetic applications in medicine and agriculture. However, governments worldwide have been exceedingly reluctant to support the introduction of genetically modified (GM) animals into agriculture. Regulatory policies have stagnated due to legal guidelines that could not anticipate the needs and solutions that are evident today. This must change if we are to maintain planetary integrity. I propose a new, market-based regulatory model for GM livestock that has both a strong scientific foundation and has worked for 10000 years. The model is similar to that for information technology in which specific algorithms drive computer and cell phone applications. Genome engineers write genetic algorithms that drive the traits in biological organisms. Accordingly, GM products should be viewed in terms of their use and public benefit rather than by limitations to the genetic programing coming from a few highly vocal groups. Genetic algorithms (Genapps) of the 21st century will include not only introduction of synthetic genes, but also complete natural and synthetic biochemical pathways to produce agricultural products that are maximally efficient, healthy to humans and animals, and sustainable in an era of changing climates while avoiding environmental degradation.

关键词： algorithms     editing     FDA     GMO     recombinant DNA     USDA    

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Modified iron-molybdate catalysts with various metal oxides by a mechanochemical method: enhanced formaldehyde

Xue Liu, Lingtao Kong, Shengtao Xu, Chaofan Liu, Fengyun Ma

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1099-1110 doi: 10.1007/s11705-020-2008-8

摘要： A mechanochemical method was employed to prepare modified iron molybdate catalysts with various metal salts as precursors. The physicochemical properties of the iron molybdate catalysts were characterized, and their performances in catalyzing the reaction from methanol to formaldehyde (HCHO) were evaluated. Iron molybdate catalysts doped with Co(NO ) ·6H O and Al(NO ) ·9H O resulted in high HCHO yields. Compared with a commercial catalyst, the HCHO yields in the reaction with the modified catalyst at an optimal Co/Mo molar ratio reached 97.37%. According to chemical state analysis, the formation of CoO and the efficient decrease in the MoO sublimation rate could be important factors enhancing the HCHO yield in reactions catalyzed with iron molybdate doped with different Co/Mo mole ratios.

关键词： iron molybdate catalyst     metal oxides     methanol to formaldehyde     Co/Mo ratio     formaldehyde yield    

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Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿（英文）》 2012年 第6卷 第2期   页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要： This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词： reactive power dispatch (RPD)     modified differential evolution (MDE)     differential evolution algorithm with localizations around the best vector (DELB)    

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Approaching the binding between Cu(II) and aerobic granules by a modified titration and µ-XRF

Hongwei LUO,Longfei WANG,Zhonghua TONG,Hanqing YU,Guoping SHENG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 362-367 doi: 10.1007/s11783-015-0803-0

摘要： Interactions between metals and activated sludge can substantially affect the fate and transport of heavy metals in wastewater treatment plants. Therefore, it is important to develop a simple, fast and efficient method to elucidate the interaction. In this study, a modified titration method with a dynamic mode was developed to investigate the binding of Cu(II), a typical heavy metal, onto aerobic granules. The titration results indicated that pH and ionic strength both had a positive effect on the biosorption capacity of the granular sludge. The -XRF results demonstrated that the distribution of metals on the granular surface was heterogeneous, and Cu showed strong correlations and had the same “hot spots” positions with other metal ions (e.g., Ca, Mg, Fe etc.). Ion exchange and complexing were the main mechanisms for the biosorption of Cu(II) by aerobic granules. These results would be beneficial for better understanding of Cu(II) migration and its fate in wastewater treatment plants.

关键词： aerobic granules     Cu(II)     modified titration     µ-XRF analysis    

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Kinetics and thermodynamics of the phosphine adsorption on the modified activated carbon

Bingnan REN

《化学科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 203-208 doi: 10.1007/s11705-010-0571-0

摘要： The kinetics and the thermodynamics of phosphine (PH ) adsorption on the modified activated carbon have been explained for the adsorption process of PH . This study investigated the kinetic and thermodynamic properties of PH adsorption on the activated carbon impregnated with 5% HCl solution. The thermodynamic properties including PH adsorption isotherm and adsorption heat were separately investigated at 20°C, 70°C, 90°C. The results showed that the Freundlich-type isotherm equation described the isotherms well. The adsorption capacity increased with increasing temperature between 20°C and 70°C. Between 70°C and 90°C, the adsorption capacity decreased obviously with increasing temperature. The adsorption capacity reached the maximum at 70°C. By analyzing the results of the kinetics and the thermodynamics, we found that the adsorption of PH was dominated by physical adsorption at the lower temperature (20°C). Then with increasing temperature, chemical adsorption gradually dominated in the adsorption process. The adsorption capacity decreased at above 70°C is due to the exothermic effects in the process of adsorption.

关键词： adsorption     PH3     activated carbon     kinetics     thermodynamics    

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Removing phosphorus from aqueous solutions by using iron-modified corn straw biochar

Fenglin LIU,Jiane ZUO,Tong CHI,Pei WANG,Bo YANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1066-1075 doi: 10.1007/s11783-015-0769-y

摘要： Iron-modified corn straw biochar was used as an adsorbent to remove phosphorus from agricultural runoff. When agricultural runoffs with a total phosphorus (TP) concentration of 1.86 mg·L to 2.47 mg·L were filtered at a hydraulic retention time of 2 h through a filtration column packed with the modified biochar, a TP removal efficiency of over 99% and an effluent TP concentration of less than 0.02 mg·L were achieved. The isotherms of the phosphorus adsorption by the modified biochar fitted the Freundlich equation better than the Langmuir equation. The mechanism of the phosphorus adsorbed by the modified biochar was analyzed by using various technologies, i.e. scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The results indicated that the surface of the modified biochar was covered by small iron granules, which were identified as Fe O . The results also showed that new iron oxides were formed on the surface of the modified biochar after the adsorption of phosphorus. Moreover, new bonds of Fe-O-P and P-C were found, which suggested that the new iron oxides tend to be Fe (PO ) (OH) . Aside from removing phosphorus, adding the modified biochar into soil also improved soil productivity. When the modified biochar-to-soil rate was 5%, the stem, root, and bean of broad bean plants demonstrated increased growth rates of 91%, 64%, and 165%, respectively.

关键词： iron-modified biochar     phosphorus removal     agricultural waste     agricultural runoff    

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Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 87-90 doi: 10.1007/s11705-009-0298-y

摘要： Amino-modified silica hydrogel (N-MSHG) was prepared by a simple sol-gel processing via the co-condensation of commercial silica sol with 3-aminopropyltrie-oxysilane. Penicillin G acylase (PGA), a model enzyme, was covalently immobilized onto the N-MSHG and then was used for the enzymatic synthesis of amoxicillin. The samples were characterized by Nitrogen sorption analysis, FT-IR and thermal gravimetric analysis (TGA). The results showed that the amino-modified gel was a mesoporous material with an average pore size of 12.64±0.17nm. The immobilization process was efficient and the immobilized enzyme showed high catalytic efficiency. The yield of the synthesis of amoxicillin in aqueous media was 38% for 2.5h. This sol-gel preparation is simple and shows prominent potential value in industrial processing.

关键词： gravimetric     amino-modified     efficient     Amino-modified     amoxicillin    

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标题 作者 时间 类型 操作

Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

期刊论文

A modified pulse charging method for lithium-ion batteries by considering stress evolution, charging

Yanfei ZHAO, Bo LU, Yicheng SONG, Junqian ZHANG

期刊论文

Comprehensive evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHPmethod and Cs dating

ZHANG Yan, GAO Xiang, ZHONG Zhenyu, PENG Buzhuo, DENG Xihai

期刊论文

Model reduction of contact dynamics simulation using a modified Lyapunov balancing method

Jianxun LIANG, Ou MA, Caishan LIU

期刊论文

Upgrade of three municipal wastewater treatment lagoons using a high surface area media

BISHOP, Fuzhi LI

期刊论文

基于修正Anderson 模型的冲击载荷下地基振动响应预测方法

房波

期刊论文

一种工业过程时变参数估计新算法——修正目标函数法

张承慧

期刊论文

Modified pretreatment method for total microbial DNA extraction from contaminated river sediment

Yun FANG,Meiying XU,Xingjuan CHEN,Guoping SUN,Jun GUO,Weimin WU,Xueduan LIU

期刊论文

Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

期刊论文

Modified iron-molybdate catalysts with various metal oxides by a mechanochemical method: enhanced formaldehyde

Xue Liu, Lingtao Kong, Shengtao Xu, Chaofan Liu, Fengyun Ma

期刊论文

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

期刊论文

Approaching the binding between Cu(II) and aerobic granules by a modified titration and µ-XRF

Hongwei LUO,Longfei WANG,Zhonghua TONG,Hanqing YU,Guoping SHENG

期刊论文

Kinetics and thermodynamics of the phosphine adsorption on the modified activated carbon

Bingnan REN

期刊论文

Removing phosphorus from aqueous solutions by using iron-modified corn straw biochar

Fenglin LIU,Jiane ZUO,Tong CHI,Pei WANG,Bo YANG

期刊论文

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

期刊论文