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Producing more with less: reducing environmental impacts through an integrated soil-crop system management approach

Zhenling CUI, Zhengxia DOU, Hao YING, Fusuo ZHANG

《农业科学与工程前沿（英文）》 2020年 第7卷 第1期   页码 14-20 doi: 10.15302/J-FASE-2019295

摘要：

Balancing crop productivity with resource use efficiency and beneficial environmental consequences is essential for sustainable agricultural development worldwide. Various strategies and approaches have been proposed and debated, but turning the concept into management practices in the field with measurable outcomes over several scales remains a challenge. An innovative approach, Integrated Soil-Crop System Management (ISSM), for producing more grain with greater nutrient use efficiencies and less environmental pollution is presented. The ISSM approach has been used in China, in field experiments as well as in thousands of farmer fields, to substantially increase the yields of maize, rice and wheat while simultaneously increasing nitrogen use efficiency and reducing environmental footprints. The scientific principle, implementation strategy and procedures of ISSM are discussed and examples of its demonstrated successes at local and regional levels across China are given. Perspectives for further development of ISSM and expanding its potential impact are also proposed and discussed.

关键词： China     environmental protection     food security     high-yielding     nitrogen management    

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Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023521

摘要：

● Score index methods readily discriminate genotypes adapted to a target environment.

关键词： Aerobic rice     breeding selection     drought resilience     production capacity index     resilience capacity index     stress score index     upland    

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混凝土结构性干预所必需的材料力学性能 Article

Tamon Ueda

《工程（英文）》 2019年 第5卷 第6期   页码 1131-1138 doi: 10.1016/j.eng.2019.02.012

摘要：

结构性干预包括修复和（或）改善结构性能。除了混凝土和钢材这两种典型的混凝土结构材料外，各种纤维增强复合材料（FRP），混合纤维、聚合物和黏合剂的黏结材料也常被用于结构性干预。为了预测结构性能，有必要开发一种不仅适用于钢材，而且适用于其他材料的通用方法。这种通用模型可以提供有关改善结构性能所需的力学性能的信息。外部黏结是一种典型的结构干预方案，在新结构中没有得到应用。为了在基体混凝土和外部黏结材料的接合点上获得更好的黏结强度，我们有必要阐明材料的性能和结构细节。本文介绍基体混凝土的力学性能和相关干预材料用于以下目的：①获得更高的抗剪强度和减少构件在结构性干预后的极限变形；②使外部黏结获得更高的黏结强度。本文得出的结论是，在有结构干预的结构中，为了提高结构的力学性能，干预材料的一些力学性能和结构细节是新的，且不同于没有干预的结构。例如，在无结构性干预的结构中，高强度和高刚度是材料的重要性能，而高断裂应力和低刚度是结构干预材料的重要性能。

关键词： 结构性干预     高断裂应力     无屈服     低刚度     粗糙度     FRP 聚合物    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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标题 作者 时间 类型 操作

Producing more with less: reducing environmental impacts through an integrated soil-crop system management approach

Zhenling CUI, Zhengxia DOU, Hao YING, Fusuo ZHANG

期刊论文

Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

期刊论文

混凝土结构性干预所必需的材料力学性能

Tamon Ueda

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