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Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

《能源前沿(英文)》 2019年 第13卷 第4期   页码 612-625 doi: 10.1007/s11708-019-0647-6

摘要: Anthropogenic climate change is a global problem that affects every country and each individual. It is largely caused by human beings emitting greenhouse gases into the atmosphere. In general, a small percentage of the population is responsible for a large amount of emissions. This paper focuses on high emitters and their CO emissions from energy use in UK homes. It applies a cluster approach, aiming to identify whether the high emitters comprise clusters where households in each cluster share similar characteristics but are different from the others. The data are mainly based on the Living Cost and Food survey in the UK. The results show that after equivalising both household emissions and income, the high emitters can be clustered into six groups which share similar characteristics within each group, but are different from the others in terms of income, age, household composition, category and size of the dwelling, and tenure type. The clustering results indicate that various combinations of socioeconomic factors, such as low-income single female living in an at least six-room property, or high-income retired couple owning a large detached house, could all lead to high CO emissions from energy use at home. Policymakers should target each high-emitter cluster differently to reduce CO emissions from energy consumption at home more effectively.

关键词: cluster analysis     emissions reduction     energy use     high emitters     household energy consumption     socioeconomic factors    

Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

Viviana Maffeis, Lisa Moni, Daniele Di Stefano, Silvia Giordani, Renata Riva

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 76-89 doi: 10.1007/s11705-019-1833-0

摘要: The search for new fluorescent molecules for possible applications as functional -electron systems and their conjugation with different nanomaterials is nowadays of paramount importance to broaden the availability of materials with different properties. Herein we present a diversity-oriented approach to heterocyclic luminophores based on a multicomponent Ugi reaction followed by a Pd-mediated cascade sequence. The new molecules are coupled to carbon nano-onions, and hybrid systems represent the first example of blue emitters conjugated with these carbon nanoparticles.

关键词: carbon nano-onions     multicomponent reactions     blue emitters     fluorescence     isoquinolines    

未知辐射源信号特征辅助的广义标签多伯努利滤波器 Research Article

国强1,滕龙1,2,吴新良2,宋文明2,黄大羽2

《信息与电子工程前沿(英文)》 2022年 第23卷 第12期   页码 1871-1880 doi: 10.1631/FITEE.2200286

摘要: 提出一种未知辐射源信号特征辅助的广义标签多伯努利滤波器。复杂电磁环境下,辐射源特征通常未知且随时间变化。针对辐射源特征未知的问题,提出一种基于数据场动态聚类的辐射源特征求解方法。针对辐射源特征时变以及对应的概率分布未知的问题,提出一种改进的模糊C-均值算法来计算目标和杂波量测的相关系数,以近似辐射源特征的似然函数。在此基础上,将辐射源特征集成到广义标签多伯努利滤波器中,从而获得新的递归方程。仿真结果表明,提出的方法可以提高对多目标的跟踪性能,尤其在强杂波环境中。

关键词: 多目标跟踪;广义标签多伯努利;辐射源信号特征;模糊C-均值;动态聚类    

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1390-1399 doi: 10.1007/s11709-021-0775-z

摘要: High viscosity asphalt (HVA) has been a great success as a drainage pavement material. However, the larger porosity of drainage asphalt mixtures weakens the cohesion and adhesion and leads to premature rutting, water damage, spalling and cracking. The purpose of this study was to investigate the rheological properties of HVA prepared using different high viscosity modifiers through conventional tests, Brookfield viscosity tests, dynamic shear rheometer tests and bending beam rheometer tests. The conventional performance results demonstrated SBS + rubber asphalt (SRA-1/2) exhibited excellent elastic recovery and low-temperature flexibility. The 60°C dynamic viscosity results indicated TPS + rubber asphalt (TRA) had the excellent adhesion. The rotational viscosity results and rheological results indicated that SRA-2 not only exhibited excellent temperature stability and workability, as well as excellent resistance to deformation and rutting resistance, but also exhibited excellent low-temperature cracking resistance and relaxation performance. Based on rheological results, the PG classification of HVA was 16% rubber + asphalt for PG76-22, 20% rubber + asphalt for PG88-22, TRA and SRA-1/2 for PG88-28. From comprehensive evaluation of the viscosity, temperature stability and sensitivity, as well as high/low temperature performance of HVA, SRA-2 was found to be more suited to the requirements of drainage asphalt pavement materials.

关键词: high viscosity asphalt     rheological properties     rubber     modifier     viscosity    

Continuous deacylation of amides in a high-temperature and high-pressure microreactor

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1818-1825 doi: 10.1007/s11705-022-2182-y

摘要: The deacylation of amides, which is widely employed in the pharmaceutical industry, is not a fast reaction under normal conditions. To intensify this reaction, a high-temperature and high-pressure continuous microreaction technology was developed, whose space-time yield was 49.4 times that of traditional batch reactions. Using the deacylation of acetanilide as a model reaction, the effects of the temperature, pressure, reaction time, molar ratio of reactants, and water composition on acetanilide conversion were carefully studied. Based on the rapid heating and cooling capabilities, the kinetics of acetanilide deacylation at high temperatures were investigated to determine the orders of reactants and activation energy. This microreaction technology was further applied to a variety of other amides to understand the influence of substituents and steric hindrance on the deacylation reaction.

关键词: amide deacylation     microreactor     flow chemistry     reaction intensification    

METAGENOMICS COMBINED WITH HIGH-THROUGHPUT SEQUENCING REVEALS THE METHANOGENIC POTENTIAL OF FRESH CORNSTRAW UNDER THERMOPHILIC AND HIGH OLR

《农业科学与工程前沿(英文)》 2023年 第10卷 第3期   页码 403-423 doi: 10.15302/J-FASE-2022471

摘要:

● Methane production from fresh straw was 7.50% higher than dry straw.

关键词: fresh corn straw     high solid anaerobic digestion     metagenomics     microbial communities     thermophilic    

Localized high-concentration electrolytes for lithium metal batteries: progress and prospect

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1354-1371 doi: 10.1007/s11705-022-2286-4

摘要: With the increasing development of digital devices and electric vehicles, high energy-density rechargeable batteries are strongly required. As one of the most promising anode materials with an ultrahigh specific capacity and extremely low electrode potential, lithium metal is greatly considered an ideal candidate for next-generation battery systems. Nevertheless, limited Coulombic efficiency and potential safety risks severely hinder the practical applications of lithium metal batteries due to the inevitable growth of lithium dendrites and poor interface stability. Tremendous efforts have been explored to address these challenges, mainly focusing on the design of novel electrolytes. Here, we provide an overview of the recent developments of localized high-concentration electrolytes in lithium metal batteries. Firstly, the solvation structures and physicochemical properties of localized high-concentration electrolytes are analyzed. Then, the developments of localized high-concentration electrolytes to suppress the formation of dendritic lithium, broaden the voltage window of electrolytes, enhance safety, and render low-temperature operation for robust lithium metal batteries are discussed. Lastly, the remaining challenges and further possible research directions for localized high-concentration electrolytes are outlined, which can promisingly render the practical applications of lithium metal batteries.

关键词: high-concentration electrolyte     localized high-concentration electrolyte     lithium metal battery     solid electrolyte interphase     dendrite    

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

《农业科学与工程前沿(英文)》 2015年 第2卷 第2期   页码 115-123 doi: 10.15302/J-FASE-2015055

摘要: This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

关键词: rice     nitrogen-efficient cultivar     grain fill     harvest index     nitrogen use efficiency     water use efficiency    

A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

《机械工程前沿(英文)》 2009年 第4卷 第2期   页码 219-223 doi: 10.1007/s11465-009-0024-y

摘要: Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150°C and 28 MPa to overcome problems of traditional high-temperature plunger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90° phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mononeuron self-adaptive PID control algorithm is also improved by modifying parameters and . Two improved controllers are used to control the two cylinders, respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

关键词: mononeuron PID control     hydraulic pump     pressure fluctuation    

CR-Fuxing high-speed EMU series

《工程管理前沿(英文)》   页码 742-748 doi: 10.1007/s42524-023-0281-1

摘要: CR-Fuxing high-speed EMU series

关键词: CR-Fuxing series     high-speed EMU     innovation     key system     digitalized collaborative design     engineering management    

Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

《工程管理前沿(英文)》 2017年 第4卷 第4期   页码 463-482 doi: 10.15302/J-FEM-2017054

摘要: This paper considers multiple perspectives to explore the concept of high-speed railway (HSR), rationally abstract its value formation mechanism, and quantitatively measure its actual performance. This paper analyzes the governance potential of major countries in the high-speed railway value chain and studies the feasible ways and development strategies to enhance the high-speed railway governance in China. Findings of this paper are as follows. First, the government, as the early manager of high-speed railway governance, has given way to Siemens and other integrated enterprises. Second, the high-speed railway standard output has become the core competitiveness that embodies high-speed railway. Third, the global high-speed railway market presents a hierarchical high-speed railway governance model and changes to a modular approach to governance.

关键词: high-speed railway value     communication value     high-speed railway value governance     governance path upgrade    

Exploration on Engineering Management Practice of China’s High Speed Railways

Yong-fu Sun

《工程管理前沿(英文)》 2014年 第1卷 第3期   页码 232-240 doi: 10.15302/J-FEM-2014043

摘要: This paper explores the principal motivations and successful experiences of the rapid development of China’s high speed railway. In the perspective of the engineering management practice, the developers have studied and made prospective mid- and long-term railway network planning, including the four east-west and four north-south corridors as the backbone, the interregional urban passenger traffic corridors and the intercity railways, with a planning scale above 16,000 km. Under the overall coordination of the government, a high speed railway technology system has been formed with the China’s characteristics, by the way of sticking to independent innovation, of combining original innovation, collaborative innovation and integrative innovation, and of attaching importance to experimental verification. The target control system and support-guarantee system were established for the high speed railway project, enacting standardized management, strengthening integration test and commissioning, conducting strict acceptance, and achieving construction management experiences on the high speed railway. Finally, this paper proposes such issues worthy of attention and further study, as the improvement of the engineering decision-making management, the enhancement of investment and financing system reform, and the promotion of professionalization and the specialization of engineering project management.

关键词: high speed railway     engineering management     practice     innovation    

Selective preparation for biofuels and high value chemicals based on biochar catalysts

《能源前沿(英文)》 2023年 第17卷 第5期   页码 635-653 doi: 10.1007/s11708-023-0878-4

摘要: The reuse of biomass wastes is crucial toward today’s energy and environmental crisis, among which, biomass-based biochar as catalysts for biofuel and high value chemical production is one of the most clean and economical solutions. In this paper, the recent advances in biofuels and high chemicals for selective production based on biochar catalysts from different biomass wastes are critically summarized. The topics mainly include the modification of biochar catalysts, the preparation of energy products, and the mechanisms of other high-value products. Suitable biochar catalysts can enhance the yield of biofuels and higher-value chemicals. Especially, the feedstock and reaction conditions of biochar catalyst, which affect the efficiency of energy products, have been the focus of recent attentions. Mechanism studies based on biochar catalysts will be helpful to the controlled products. Therefore, the design and advancement of the biochar catalyst based on mechanism research will be beneficial to increase biofuels and the conversion efficiency of chemicals into biomass. The advanced design of biochar catalysts and optimization of operational conditions based on the biomass properties are vital for the selective production of high-value chemicals and biofuels. This paper identifies the latest preparation for energy products and other high-value chemicals based on biochar catalysts progresses and offers insights into improving the yield of high selectivity for products as well as the high recyclability and low toxicity to the environment in future applications.

关键词: biomass     biochar catalysts     biofuels     high chemicals    

vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

《能源前沿(英文)》 2017年 第11卷 第1期   页码 85-91 doi: 10.1007/s11708-016-0437-3

摘要: The intrinsic a-Si:H passivation layer inserted between the doped a-Si:H layer and the c-Si substrate is very crucial for improving the performance of the a-Si:H/c-Si heterojunction (SHJ) solar cell. The passivation performance of the a-Si:H layer is strongly dependent on its microstructure. Usually, the compact a-Si:H deposited near the transition from the amorphous phase to the nanocrystalline phase by plasma enhanced chemical vapor deposition (PECVD) can provide excellent passivation. However, at the low deposition pressure and low deposition power, such an a-Si:H layer can be only prepared in a narrow region. The deposition condition must be controlled very carefully. In this paper, intrinsic a-Si:H layers were prepared on n-type Cz c-Si substrates by 27.12 MHz PECVD at a high deposition pressure and high deposition power. The corresponding passivation performance on c-Si was investigated by minority carrier lifetime measurement. It was found that an excellent a-Si:H passivation layer could be obtained in a very wide deposition pressure and power region. Such wide process window would be very beneficial for improving the uniformity and the yield for the solar cell fabrication. The a-Si:H layer microstructure was further investigated by Raman and Fourier transform infrared (FTIR) spectroscopy characterization. The correlation between the microstructure and the passivation performance was revealed. According to the above findings, the a-Si:H passivation performance was optimized more elaborately. Finally, a large-area SHJ solar cell with an efficiency of 22.25% was fabricated on the commercial 156 mm pseudo-square n-type Cz c-Si substrate with the open-circuit voltage ( ) of up to 0.732 V.

关键词: PECVD     high pressure and high power     a-Si:H microstructure     passivation     heterojunction solar cell    

Slender reinforced concrete shear walls with high-strength concrete boundary elements

《结构与土木工程前沿(英文)》 2023年 第17卷 第1期   页码 138-151 doi: 10.1007/s11709-022-0897-y

摘要: Reinforced concrete structural walls are commonly used for resisting lateral forces in buildings. Owing to the advancements in the field of concrete materials over the past few decades, concrete mixes of high compressive strength, commonly referred to as high-strength concrete (HSC), have been developed. In this study, the effects of strategic placement of HSC on the performance of slender walls were examined. The finite-element model of a conventional normal-strength concrete (NSC) prototype wall was validated using test data available in extant studies. HSC was incorporated in the boundary elements of the wall to compare its performance with that of the conventional wall at different axial loads. Potential reductions in the reinforcement area and size of the boundary elements were investigated. The HSC wall exhibited improved strength and stiffness, and thereby, allowed reduction in the longitudinal reinforcement area and size of the boundary elements for the same strength of the conventional wall. Cold joints resulting from dissimilar concrete pours in the web and boundary elements of the HSC wall were modeled and their impact on behavior of the wall was examined.

关键词: slender walls     high-strength concrete     rectangular and barbell-shaped walls     cold joints    

标题 作者 时间 类型 操作

Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

期刊论文

Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

Viviana Maffeis, Lisa Moni, Daniele Di Stefano, Silvia Giordani, Renata Riva

期刊论文

未知辐射源信号特征辅助的广义标签多伯努利滤波器

国强1,滕龙1,2,吴新良2,宋文明2,黄大羽2

期刊论文

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

期刊论文

Continuous deacylation of amides in a high-temperature and high-pressure microreactor

期刊论文

METAGENOMICS COMBINED WITH HIGH-THROUGHPUT SEQUENCING REVEALS THE METHANOGENIC POTENTIAL OF FRESH CORNSTRAW UNDER THERMOPHILIC AND HIGH OLR

期刊论文

Localized high-concentration electrolytes for lithium metal batteries: progress and prospect

期刊论文

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

期刊论文

A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

期刊论文

CR-Fuxing high-speed EMU series

期刊论文

Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

期刊论文

Exploration on Engineering Management Practice of China’s High Speed Railways

Yong-fu Sun

期刊论文

Selective preparation for biofuels and high value chemicals based on biochar catalysts

期刊论文

vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

期刊论文

Slender reinforced concrete shear walls with high-strength concrete boundary elements

期刊论文