资源类型

期刊论文 11

年份

2023 2

2021 1

2019 2

2016 3

2012 1

2004 1

关键词

Rough集 1

函数拟合 1

模糊神经网络 1

规则获取 1

检索范围:

排序: 展示方式:

Effects of reducing agent and approaching anodes on chromium removal in electrokinetic soil remediation

Xiaona WEI,Shuhai GUO,Bo WU,Fengmei LI,Gang LI

《环境科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 253-261 doi: 10.1007/s11783-015-0791-0

摘要: A soil remediation method combining in situ reduction of Cr(VI) with approaching anodes electrokinetic (AAs-EK) remediation is proposed. EK experiments were conducted to compare the effect of approaching anodes (AAs) and fixed electrodes (FEs) with and without sodium bisulfite (NaHSO ) as a reducing agent. When NaHSO was added to the soil before EK treatment, 90.3% of the Cr(VI) was reduced to Cr(III). EK experiments showed that the adverse effect of contrasting migration of Cr(III) and Cr(VI) species, which limits the practical application of this technique, was eliminated in the presence of the reducing agent. Furthermore, Tessier fractionation analysis indicated that the reducing agent changed the distribution of the chemical forms of Cr. The AAs-EK method was shown to acidize the soil as the anode moved toward the cathode and this acid front pushed the “focusing” region toward the cathode. After remediation, the pH of the soil was between 1.8 and 5.0 in AAs-EK experiments. The total Cr removal efficiency was 64.4% (except in the “focusing” region) when the reduction reaction was combined with AAs-EK method. We conclude that AAs-EK remediation in the presence of NaHSO is an appropriate method for Cr-contaminated soil.

关键词: chromium     reduction reaction     contrasting migration     approaching anode     electrokinetic    

Enhanced electrokinetic remediation of chromium-contaminated soil using approaching anodes

Shucai LI, Tingting LI, Gang LI, Fengmei LI, Shuhai GUO

《环境科学与工程前沿(英文)》 2012年 第6卷 第6期   页码 869-874 doi: 10.1007/s11783-012-0437-4

摘要: As a new technology used for the cleaning of chromium-contaminated soil, worldwide interest in eletrokinetic (EK) remediation has grown considerably in recent times. However, owing to the fact that chromium exists as both cationic and anionic species in the soil, it is not an efficient method. This paper reports upon a study in which a process using approaching anodes (AAs) was used to enhance the removal efficiency of chromium by eletrokinetics. Two bench-scale experiments to remove chromium from contaminated soil were performed, one using a fixed anode (FA) and the other using AAs. In the AAs experiment, the anode moved toward the cathode by 7 cm every three days. After remediation, soil pH, total chromium, and fractionation of chromium in the soil were determined. The average removal efficiency of total chromium was 11.32% and 18.96% in the FA and AAs experiments, respectively. After remediation, acidic soil conditions throughout the soil were generated through the use of AAs, while 80% of the soil remained neutral or alkalic when using the FA approach. The acidic soil environment and high field intensity in the AAs experiment might have favored chromium desorption, dissolution and dissociation from the soil, plus the mobility of chromium in the soil was also enhanced. The results demonstrate that AAs used in the process of EK remediation can enhance the efficiency of chromium removal from soil.

关键词: approaching anodes     chromium-contaminated soil     electrokinetics     chromium fractionation    

Experimental and modeling studies on installation of arc sprayed Zn anodes for protection of reinforced

Xianming SHI

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 1-11 doi: 10.1007/s11709-016-0312-7

摘要: Arc sprayed zinc (Zn) anode on concrete surfaces has been an emerging technology for protecting reinforced concrete structures from rebar corrosion in coastal environments. Many cathodic protection (CP) systems with arc sprayed Zn anodes will reach or exceed their design life in the near future and thus may function improperly or insufficiently, making it necessary to replace the aged anodes. However, prior to this study, little was known about the most effective profile for the concrete surface, for either new concrete or old concrete with existing Zn anodes removed. This work develops criteria to properly prepare the concrete surface before the application of new Zn anode. Experimental studies were conducted both in the laboratory and for a field structure in Oregon. Artificial neural network was used to achieve better understanding of the complex cause-and-effect relationships inherent in the Zn-mortar or Zn–concrete systems and was successful in finding meaningful, logical results from the bond strength data. The goal is to achieve strong initial bond strength of new Zn to concrete, which is essential for long-term performance of the CP system. The results from this case study suggest that it is necessary to adjust the anode removal and surface sandblasting based on the electrochemical age of the existing concrete. In all cases of sandblasting, minimize the exposure of large aggregates (e.g., those bigger than 19 mm in diameter).

关键词: arc sprayed Zn     anode replacement     reinforced concrete     bridge preservation     neural networks     surface profile    

Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

《能源前沿(英文)》 doi: 10.1007/s11708-023-0870-z

摘要: Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

关键词: threshold solar water     splitting hydrogen III    

Role of oxygen vacancy inducer for graphene in graphene-containing anodes

《化学科学与工程前沿(英文)》 2023年 第17卷 第3期   页码 326-333 doi: 10.1007/s11705-022-2213-8

摘要: Currently, graphene is only considered as a conductive additive and expansion inhibitor in oxides/graphene composite anodes. In this study, a new graphene role (oxygen vacancy inducer) in graphene/oxides composites anodes, which are treated at high-temperature, is proposed and verified using experiments and density functional theory calculations. During high-temperature processing, graphene forms carbon vacancies due to increased thermal vibration, and the carbon vacancies capture oxygen atoms, facilitating the formation of oxygen vacancies in oxides. Moreover, the induced oxygen vacancy concentrations can be regulated by sintering temperatures, and the behavior is unaffected by oxide crystal structures (crystalline and amorphous) and morphology (size and shape). According to density functional theory calculations and electrochemical measurements, the oxygen vacancies enhance the lithium-ion storage performance. The findings can result in a better understanding of graphene’s roles in graphene/oxide composite anodes, and provide a new method for designing high-performance oxide anodes.

关键词: oxide     oxygen vacancy     graphene     anode     density functional theory calculation    

Promoting Si-graphite composite anodes with SWCNT additives for half and NCM811 full lithium ion batteries

Jingning SHAN, Xiaofang YANG, Chao YAN, Yiguang JU, Lin CHEN, Fang ZHAO

《能源前沿(英文)》 2019年 第13卷 第4期   页码 626-635 doi: 10.1007/s11708-019-0650-y

摘要: Single wall carbon nanotube (SWCNT) additives were formulated into µm-Si-graphite composite electrodes and tested in both half cells and full cells with high nickel cathodes. The critical role of small amount of SWCNT addition (0.2 wt%) was found for significantly improving delithiation capacity, first cycle coulombic efficiency (FCE), and capacity retention. Particularly, Si (10 wt%)-graphite electrode exhibits 560 mAh/g delithiation capacity and 92% FCE at 0.2 C during the first charge-discharge cycle, and 91% capacity retention after 50 cycles (0.5 C) in a half cell. Scanning electron microscope (SEM) was used to illustrate the electrode morphology, compositions and promoting function of the SWCNT additives. In addition, full cells assembled with high nickel-NCM811 cathodes and µm-Si-graphite composite anodes were evaluated for the consistence between half and full cell performance, and the consideration for potential commercial application. Finally, criteria to assess Si-containing anodes are proposed and discussed from an industrial perspective.

关键词: lithium-ion battery     Si anode     Si-graphite composite     single wall carbon nanotube (SWCNT)     NCM811    

Approach for natural gas to be a primary energy source in China

Weihe HUANG, Jindian CHEN, Chuan FU, Yan HUANG

《工程管理前沿(英文)》 2019年 第6卷 第4期   页码 467-476 doi: 10.1007/s42524-019-0068-6

摘要: This work reveals the positioning of natural gas in the evolution of world energy and the general law of its development. In the long-term adjustment of energy structure, natural gas has gradually become the primary energy source because of five factors: policy, resources, technology, facilities, and market. To expedite the revolution of energy production and consumption, China must urgently expand the use of natural gas toward a more positive role in complementing coal and renewable energy and prioritize its usage in three areas, namely, urban gas, power generation, and industrial fuel. Natural gas is expected to account for approximately 15% of China’s total energy consumption in the future. For natural gas to be the primary energy, the exploitation of gas resources must be expanded, resource access must be improved, a flexible trade system must be set up, infrastructure investment must be increased, and the security system must be enhanced.

关键词: natural gas     energy revolution     primary energy     utilization areas     approaching means    

Fe

Lifeng Zhang, Yifei Song, Weiping Wu, Robert Bradley, Yue Hu, Yi Liu, Shouwu Guo

《化学科学与工程前沿(英文)》 2021年 第15卷 第1期   页码 156-163 doi: 10.1007/s11705-020-1986-x

摘要: Unique self-assembled iron(II) molybdenum(IV) oxide (Fe Mo O ) mesoporous hollow spheres have been facilely constructed the bubble-template-assisted hydrothermal synthesis method combined with simple calcination. The compact assembly of small nanoparticles on the surface of the hollow spheres not only provides more active sites for the Fe Mo O , but also benefits the stability of the hollow structure, and thus improved the lithium storage properties of Fe Mo O . The Fe Mo O mesoporous hollow spheres exhibit high initial discharge and charge capacities of 1189 and 997 mA∙h∙g respectively, as well as good long-term cycling stability (866 mA∙h∙g over 70 cycles) when used as a lithium-ion battery anode. This feasible material synthesis strategy will inspire the variation of structural design in other ternary metal molybdates.

关键词: molybdates     Fe2Mo3O8     hollow spheres     lithium ion batteries     anodes    

基于Rough集理论的模糊神经网络构造方法

黄显明,易继锴

《中国工程科学》 2004年 第6卷 第4期   页码 44-50

摘要:

提出了在模糊神经网络中使用Rough集理论进行网络结构设计的方法。由于Rough集理论有强大的数值分析能力,而模糊神经网络具有准确的逼近收敛能力和较高的精度,所以通过两者的结合,可以得到一种可理解性好、计算简单、收敛速度快的神经网络模型。这种网络构造方法的主要过程为:首先,利用Rough集理论对给定数据集进行规则获取;然后,根据这些规则构造模糊神经网络各层的神经元个数及相关参数初始值;最后,用BP算法迭代求出网络的各种参数,完成网络的设计。给出了一个二维非线性函数拟合的实例,进一步验证了方法的正确性。

关键词: 模糊神经网络     Rough集     规则获取     函数拟合    

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    

Approaching the upper boundary of driver-response relationships: identifying factors using a novel framework

《环境科学与工程前沿(英文)》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1676-2

摘要:

● A novel framework integrating quantile regression with machine learning is proposed.

关键词: Driver-response     Upper boundary of relationship     Interpretable machine learning     Quantile regression     Total phosphorus     Chlorophyll a    

标题 作者 时间 类型 操作

Effects of reducing agent and approaching anodes on chromium removal in electrokinetic soil remediation

Xiaona WEI,Shuhai GUO,Bo WU,Fengmei LI,Gang LI

期刊论文

Enhanced electrokinetic remediation of chromium-contaminated soil using approaching anodes

Shucai LI, Tingting LI, Gang LI, Fengmei LI, Shuhai GUO

期刊论文

Experimental and modeling studies on installation of arc sprayed Zn anodes for protection of reinforced

Xianming SHI

期刊论文

Approaching the commercial threshold of solar water splitting toward hydrogen by III-nitrides nanowires

期刊论文

Role of oxygen vacancy inducer for graphene in graphene-containing anodes

期刊论文

Promoting Si-graphite composite anodes with SWCNT additives for half and NCM811 full lithium ion batteries

Jingning SHAN, Xiaofang YANG, Chao YAN, Yiguang JU, Lin CHEN, Fang ZHAO

期刊论文

Approach for natural gas to be a primary energy source in China

Weihe HUANG, Jindian CHEN, Chuan FU, Yan HUANG

期刊论文

Fe

Lifeng Zhang, Yifei Song, Weiping Wu, Robert Bradley, Yue Hu, Yi Liu, Shouwu Guo

期刊论文

基于Rough集理论的模糊神经网络构造方法

黄显明,易继锴

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

Approaching the upper boundary of driver-response relationships: identifying factors using a novel framework

期刊论文