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CH₄ and N₂O emissions from double-rice cropping system as affected by Chinese milk

Heshui XU,Dengyun LI,Bo ZHU,Kai ZHANG,Yadong YANG,Chen WANG,Ying JIANG,Zhaohai ZENG

《农业科学与工程前沿（英文）》 2017年第4卷第1期页码 59-68 doi: 10.15302/J-FASE-2017137

摘要： Chinese milk vetch (CMV) and rice straw (RS) were incorporated into soil to substitute for synthetic N fertilizers and to maintain soil fertility. However, little is known about the integrated impacts of CMV and RS incorporation on CH and N O emissions in double-rice cropping systems in southern China. A field experiment was conducted to estimate the integrated impacts of CMV and RS incorporation in the early- and late-rice seasons on CH and N O emissions. All treatments received uniform N inputs, 6%–37% of which was replaced by CMV and RS crop residue. CMV and/or RS incorporation produced equivalent or slightly more grain yield, while reducing N O emissions by 3%–43%. However, both CMV and RS incorporation increased CH emissions. Annual CH emissions ranged from 321 to 614 kg·hm from CMV and RS amendment treatments, which were 1.5–2.9 times higher than that from synthetic N. Compared with single synthetic N fertilizer, incorporation of CMV and/or RS increased GWP and yield-scaled GWP by 45%–164% and 45%–153%, respectively. Our results demonstrate CMV and RS amendments replacing N fertilizer, maintained stable yield, mitigated N O emission, but enhanced CH emission. Further study is needed on crop residue management in double-cropping rice systems.

关键词： Chinese milk vetch CH₄ double-rice cropping system grain yield N₂O rice straw

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DESIGNING DIVERSIFIED CROPPING SYSTEMS IN CHINA: THEORY, APPROACHES AND IMPLEMENTATION

《农业科学与工程前沿（英文）》 2021年第8卷第3期页码 362-372 doi: 10.15302/J-FASE -2021392

摘要：

Intensive agriculture in China over recent decades has successfully realized food security but at the expense of negative environmental impacts. Achieving green transformation of agriculture in China requires fundamental restructuring of cropping systems. This paper presents a theoretical framework of theory, approaches and implementation of crop diversification schemes in China. Initially, crop diversification schemes require identifying multiple objectives by simultaneously considering natural resources, limiting factors/constraints, and social and economic demands of different stakeholders. Then, it is necessary to optimize existing and/or design novel cropping systems based upon farming practices and ecological principles, and to strengthen targeted ecosystem services to achieve the identified objectives. Next, the resulting diversified cropping systems need to be evaluated and examined by employing experimental and modeling approaches. Finally, a strategic plan, as presented in this paper, is needed for implementing an optimized crop diversification in China based upon regional characteristics with the concurrent objectives of safe, nutritious food production and environmental protection. The North China Plain is used as an example to illustrate the strategic plan to optimize and design diversified cropping systems. The implementation of crop diversification in China will set an example for other countries undergoing agricultural transition, and contribute to global sustainable development.

关键词： Agriculture Green Development ， crop diversification ， cropping system modeling ， ecosystem services ， sustainable agriculture

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南方双季稻区冬油菜早熟品种选育和机械栽培研究进展

官春云,陈社员,吴明亮

《中国工程科学》 2010年第12卷第2期页码 4-10

摘要：

为促进南方双季稻区冬油菜生产的发展，选育出油菜早熟品种和实行机械栽培是生产急需解决的两大问题。课题组经过近5年的系统研究，现已成功选育出5个早熟、双低、抗病、高含油量的油菜新组合（品系）。成功研制了适合油菜免耕（浅耕）直播要求的2BYF（D）—6型油菜免耕直播联合播种机，并配套研究了适合直播油菜要求的一次性施用控释肥；同时配合农艺上的催熟剂的开发与使用，研制了与高密度早熟油菜品种相配套的4YC-200油菜联合收割机。形成了在南方双季稻区机械化种植油菜农艺操作规程。通过以上集成技术的实施，实现了油菜种植成本降低，种植面积扩大，油菜产量和种植经济效益的提高，试验测定，通过机械化种植油菜，每公顷纯收入可增至4 500元以上。

关键词：双季稻油菜早熟品种机械栽培控释肥催熟剂

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Methodological considerations for redesigning sustainable cropping systems: the value of data-mininglarge and detailed farm data sets at the cropping system level

Nicolas MUNIER-JOLAIN, Martin LECHENET

《农业科学与工程前沿（英文）》 2020年第7卷第1期页码 21-27 doi: 10.15302/J-FASE-2019292

摘要：

Redesigning cropping and farming systems to enhance their sustainability is mainly addressed in scientific studies using experimental and modeling approaches. Large data sets collected from real farms allow for the development of innovative methods to produce generic knowledge. Data mining methods allow for the diversity of systems to be considered holistically and can take into account the diversity of production contexts to produce site-specific results. Based on the very few known studies using such methods to analyze the crop management strategies affecting pesticide use and their effect on farm performance, we advocate further investment in the development of large data sets that can support future research programs on farming system design.

关键词： data mining holistic Integrated Pest Management economics DEPHY network.

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DESIGNING DIVERSIFIED CROPPING SYSTEMS IN CHINA: THEORY, APPROACHES AND IMPLEMENTATION

Wen-Feng CONG, Chaochun ZHANG, Chunjie LI, Guangzhou WANG, Fusuo ZHANG

《农业科学与工程前沿（英文）》页码 362-372 doi: 10.15302/J-FASE-2021392

摘要： Intensive agriculture in China over recent decades has successfully realized food security but at the expense of negative environmental impacts. Achieving green transformation of agriculture in China requires fundamental restructuring of cropping systems. This paper presents a theoretical framework of theory, approaches and implementation of crop diversification schemes in China. Initially, crop diversification schemes require identifying multiple objectives by simultaneously considering natural resources, limiting factors/constraints, and social and economic demands of different stakeholders. Then, it is necessary to optimize existing and/or design novel cropping systems based upon farming practices and ecological principles, and to strengthen targeted ecosystem services to achieve the identified objectives. Next, the resulting diversified cropping systems need to be evaluated and examined by employing experimental and modeling approaches. Finally, a strategic plan, as presented in this paper, is needed for implementing an optimized crop diversification in China based upon regional characteristics with the concurrent objectives of safe, nutritious food production and environmental protection. The North China Plain is used as an example to illustrate the strategic plan to optimize and design diversified cropping systems. The implementation of crop diversification in China will set an example for other countries undergoing agricultural transition, and contribute to global sustainable development.

关键词： Agriculture Green Development crop diversification cropping system modeling ecosystem services sustainable agriculture

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IMPROVING FERTILIZATION METHODS AND CROPPING SYSTEMS FOR SUSTAINABLE PRODUCTION OF PEARL MILLET () IN

《农业科学与工程前沿（英文）》 2022年第9卷第4期页码 588-601 doi: 10.15302/J-FASE-2021422

摘要：

● Constraints in cultivation and production of pearl millet in West Africa are summarized.

关键词： integrated management system pearl millet Science and Technology Backyard West Africa

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Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

《能源前沿（英文）》 2021年第15卷第1期页码 222-234 doi: 10.1007/s11708-017-0480-8

摘要： Architectural shade is an effective method for improving building energy efficiency. A new shade combined with the double skin façade (DSF) system, called middle shade (MS), was introduced and developed for buildings. In this paper, a 3D dynamic simulation was conducted to analyze the influence of MS combined with DSF on the indoor thermal characteristics. The research on MS for DSF involves the temperature, the ventilation rate, the velocity distribution of the air flow duct, and the indoor temperature. The results show that the angle and position of the shade in the three seasons are different, and different conditions effectively enhance the indoor thermal characteristics. In summer, the appearance of MS in DSF makes the indoor temperature significantly lower. The indoor temperature is obviously lower than that of the air flow duct, and the temperature of the air flow duct is less affected by MS. The influence of the position of blinds on indoor temperature and ventilation rate is greater than the influence of the angle of blinds. According to the climate characteristics of winter and transition season, in winter, early spring, and late autumn, the indoor temperature decreases with the increase of the position of blinds at daytime, but the opposite is true at night. The results found in this paper can provide reference for the design and use of MS combined with DSF in hot summer and cold winter zone.

关键词： middle shade position thermal characteristics double skin facade

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AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

《农业科学与工程前沿（英文）》 2022年第9卷第2期页码 284-294 doi: 10.15302/J-FASE-2021435

摘要：

Bioenergy, currently the largest renewable energy source in the EU (64% of the total renewable energy consumption), has sparked great interest to meet the 32% renewable resources for the 2030 bioeconomy goal. The design of innovative cropping systems informed by bioeconomy imperatives requires the evaluate of the effects of introducing crops for bioenergy into conventional crop rotations. This study aimed to assess the impacts of changes in conventional cropping systems in mixed dairy cattle farms redesigned to introduce bioenergy crops either by increasing the biomass production through an increase of cover crops, while keeping main feed/food crops, or by substituting food crops with an increase of the crop rotation length. The assessment is based on the comparison between conventional and innovative systems oriented to feed and biogas production, with and without tillage, to evaluate their agri-environmental performances (biomass production, nitrogen fertilization autonomy, greenhouse gas emissions and biogas production). The result showed higher values in the biogas cropping system than in the conventional and feed ones for all indicators, biomass productivity (27% and 20% higher, respectively), nitrogen fertilization autonomy (26% and 73% higher, respectively), methanogenic potential (77% and 41% higher, respectively) and greenhouse gas emissions (15% and 3% higher, respectively). There were no negative impacts of no-till compared to the tillage practice, for all tested variables. The biogas cropping system showed a better potential in terms of agri-environmental performance, although its greenhouse gas emissions were higher. Consequently, it would be appropriate to undertake a multicriteria assessment integrating agri-environmental, economic and social performances.

关键词： alternative cropping systems / bioeconomy / biogas / biomass production / fertilization autonomy / greenhouse gas assessment

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SUSTAINABLE SUGARCANE CROPPING IN CHINA

《农业科学与工程前沿（英文）》 2022年第9卷第2期页码 272-283 doi: 10.15302/J-FASE-2022442

摘要：

Demand for sugar is projected to grow in China for the foreseeable future. However, sugarcane production is unlikely to increase due to increasing production cost and decreasing profit margin. The persisting sugarcane yield plateau and the current cropping system with fertilizer overuse, soil acidification and pests and diseases remain the major productivity constraints. Sugarcane agriculture supports the livelihood of about 28 million farmers in South China; hence, sustaining it is a socioeconomic imperative. More compellingly, to meet the ever-increasing Chinese market demand, annual sugar production must be increased from the current 10 Mt to 16 Mt by 2030 of which 80% to 90% comes from sugarcane. Therefore, increasing sugar yield and crop productivity in an environmentally sustainable way must be a priority. This review examines the current Chinese sugarcane production system and discuss options for its transition to a green, sustainable cropping system, which is vital for the long-term viability of the industry. This analysis shows that reducing chemical inputs, preventing soil degradation, improving soil health, managing water deficit, provision of clean planting material, and consolidation of small farm holdings are critical requirements to transform the current farming practices into an economically and environmentally sustainable sugarcane cropping system.

关键词： sustainable sugarcane cropping / soil health / rotation and intercropping / soil acidification

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Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

《能源前沿（英文）》 2008年第2卷第1期页码 36-42 doi: 10.1007/s11708-008-0013-6

摘要： A new tandem double-capillary tube refrigeration system for refrigerator-freezers is proposed. A capillary tube was added between the two evaporators in the fresh and frozen food storage chests to raise the evaporation temperature of the refrigerating chamber, and reduce the heat exchange temperature difference and the available energy loss. Peng-Robinson (P-R) equation of state was adopted to calculate the thermodynamic properties of the refrigerants, and the available energy analysis of the vapor compression refrigeration cycle was programmed to calculate the thermodynamic performances of the new and the conventional refrigeration cycle of the refrigerator-freezer. The calculation results show that the available energy efficiency of the conventional refrigeration cycle of the refrigerator-freezer is 21.20% and 20.57%, respectively when the refrigerant is R12 and R134a, while that of the double-capillary tube refrigeration cycle of the refrigerator-freezer is 23.97% and 23.44%, respectively. By comparison, the available energy efficiency of the new refrigeration system increases by 13.07% and 13.95%, respectively.

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Heating energy savings potential from retrofitting old apartments with an advanced double-skin façadesystem in cold climate

Yeo Beom YOON, Byeongmo SEO, Brian Baewon KOH, Soolyeon CHO

《能源前沿（英文）》 2020年第14卷第2期页码 224-240 doi: 10.1007/s11708-020-0801-1

摘要： Apartments account for over 60% of total residential buildings and consume a significant portion of primary energy in South Korea. Various energy efficiency measures have been implemented for both new apartment constructions and existing apartment retrofits. Old apartment structures have poor thermal performances, resulting in a high energy consumption. The South Korean government initiated retrofitting projects to improve the energy efficiency in old apartments. Apartment owners typically replace old windows with high-performance windows; however, there is still a demand for better and more innovative retrofit methods for a highly improved energy efficiency. This paper proposes an advanced double-skin façade (DSF) system to replace existing balcony windows in old apartments. Considering the cold climate conditions of Seoul, South Korea, it mainly discusses heating energy savings. Three case models were developed: Base-Case with existing apartment, Case-1 with typical retrofitting, and Case-2 with the proposed DSF system. The EnergyPlus simulation program was used to develop simulation models for a floor radiant heating system. A typical gas boiler was selected for low-temperature radiant system modeling. The air flow network method was used to model the proposed DSF system. Five heating months, i.e., November to March, and one representative day, i.e., January 24, were selected for detailed analysis. The main heat loss areas consist of windows, walls, and infiltration. The results reveal that the apartment with the DSF retrofit saves 38.8% on the annual heating energy compared to the Base-Case and 35.2% compared to Case-1.

关键词： double-skin façade retrofitting high-rise apartment heating energy building simulation

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Separation mechanism for double cylinder with shrink fitting system used for ceramics conveying rollers

Wenbin LI, Hiromasa SAKAI, Shota HARADA, Yasushi TAKASE, Nao-Aki NODA

《机械工程前沿（英文）》 2011年第6卷第3期页码 277-286 doi: 10.1007/s11465-011-0234-y

摘要：

Steel conveying rollers used in hot rolling mills must be exchanged frequently at great cost because hot conveyed strips induce wear and deterioration on the surface of roller in short periods. In previous studies, new roller structure was considered which has a ceramics sleeve connected with two steel shafts at both ends by shrink fitting. Here, although the ceramics sleeve can be used for many years, the steel shafts sometimes have to be exchanged for maintenance and reconstruction under the corrosive atmosphere. Since the thermal expansion coefficient of steel is about five times larger than that of ceramics, it is necessary to investigate how to separate the shrink fitting system by heating outside of sleeve and cooling inside of the shaft. Although how to separate the real roller has been discussed in the previous study, the separation mechanism has not been clarified yet. Therefore, in this study, several types of more fundamental models are investigated to understand the separation mechanism of real roller by the application of the finite element method. The results may be useful for designs of new rollers.

关键词： contact ceramics thermal stress heating finite element method

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现代建模与优化技术研究——在三江平原井灌水稻节水灌溉系统中的应用

付强

《中国工程科学》 2002年第4卷第6期页码 44-55

摘要：

将SPAC模型理论变相宏观应用于三江平原井灌水稻节水灌溉系统中，将地下水、农用机井、晒水池、渠道、本田池、环境因子等纳入整体系统，在各个子系统中综合运用现代建模与优化技术，通过有关机理与理论研究，建立相关的数学模型。对地下水、晒水池、渠道及水稻水分生产函数、水稻需水量、有效降雨等6个子系统进行建模与分析，制定了非充分灌溉条件下优化灌溉制度。最后通过典型示范小区的优化设计，将节水技术组装，实现了增温5～15℃，节水171%，增产700～1000 kg/hm²的目标。

关键词：建模优化三江平原井灌水稻节水灌溉系统

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Effects of nano-silicon and common silicon on lead uptake and translocation in two rice cultivars

Jianguo LIU,Hui CAI,Congcong MEI,Mingxin WANG

《环境科学与工程前沿（英文）》 2015年第9卷第5期页码 905-911 doi: 10.1007/s11783-015-0786-x

摘要： The current study investigated the effects of nano-silicon (Si) and common Si on lead (Pb) toxicity, uptake, translocation, and accumulation in the rice cultivars Yangdao 6 and Yu 44 grown in soil containing two different Pb levels (500 mg·kg and 1000 mg·kg ). The results showed that Si application alleviated the toxic effects of Pb on rice growth. Under soil Pb treatments of 500 and 1000 mg·kg , the biomasses of plants supplied with common Si and nano-Si were 1.8%–5.2% and 3.3%–11.8% higher, respectively, than those of plants with no Si supply (control). Compared to the control, Pb concentrations in rice shoots supplied with common Si and nano-Si were reduced by 14.3%–31.4% and 27.6%–54.0%, respectively. Pb concentrations in rice grains treated with common Si and nano-Si decreased by 21.3%–40.9% and 38.6%–64.8%, respectively. Pb translocation factors (TFs) from roots to shoots decreased by 15.0%–29.3% and 25.6%–50.8%, respectively. The TFs from shoots to grains reduced by 8.3%–13.7% and 15.3%–21.1%, respectively, after Si application. The magnitudes of the effects observed on plants decreased in the following order: nano-Si treatment>common Si treatment and high-grain-Pb-accumulating cultivar (Yangdao 6)>low-grain-Pb-accumulating cultivar (Yu 44) and heavy Pb stress (1000 mg·kg )>moderate Pb stress (500 mg·kg )>no Pb treatment. The results of the study indicate that nano-Si is more efficient than common Si in ameliorating the toxic effects of Pb on rice growth, preventing Pb transfer from rice roots to aboveground parts, and blocking Pb accumulation in rice grains, especially in high-Pb-accumulating rice cultivars and in heavily Pb-polluted soils.

关键词： silicon (Si) lead (Pb) rice (Oryza sativa L.) toxicity accumulation

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Stability analysis and optimization of excavation method of double-arch tunnel with an extra-large span

Yiguo XUE, Huimin GONG, Fanmeng KONG, Weimin YANG, Daohong QIU, Binghua ZHOU

《结构与土木工程前沿（英文）》 2021年第15卷第1期页码 136-146 doi: 10.1007/s11709-020-0710-8

摘要： The Xiamen Haicang double-arch tunnel has a maximum span of 45.73 m and a minimum burial depth of 5.8 m. A larger deformation or collapse of the tunnel is readily encountered during tunnel excavation. It is therefore necessary to select a construction approach that is suitable for double-arch tunnel projects with an extra-large span. In this study, three construction methods for double-arch tunnels with extra-large spans were numerically simulated. Subsequently, the deformation behavior and stress characteristics of the surrounding rock were obtained and compared. The results showed that the double-side-drift method with temporary vertical support achieves better adaptability in the construction of such tunnels, which can be observed from both the numerical results and monitoring data. In addition, the improved temporary support plays a critical role in controlling the surrounding rock deformation. In addition, the disturbance resulting from the excavation of adjacent drifts was obvious, particularly the disturbance of the surrounding rock caused by the excavation of the middle drift. The present findings can serve as the initial guidelines for the construction of ultra-shallowly buried double-arch tunnels with extra-large spans.

关键词： double-arch tunnel triple-layer composite liner system numerical modeling stress analysis settlement

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标题作者时间类型操作

CH₄ and N₂O emissions from double-rice cropping system as affected by Chinese milk

Heshui XU,Dengyun LI,Bo ZHU,Kai ZHANG,Yadong YANG,Chen WANG,Ying JIANG,Zhaohai ZENG

期刊论文

DESIGNING DIVERSIFIED CROPPING SYSTEMS IN CHINA: THEORY, APPROACHES AND IMPLEMENTATION

期刊论文

南方双季稻区冬油菜早熟品种选育和机械栽培研究进展

官春云,陈社员,吴明亮

期刊论文

Methodological considerations for redesigning sustainable cropping systems: the value of data-mininglarge and detailed farm data sets at the cropping system level

Nicolas MUNIER-JOLAIN, Martin LECHENET

期刊论文

DESIGNING DIVERSIFIED CROPPING SYSTEMS IN CHINA: THEORY, APPROACHES AND IMPLEMENTATION

Wen-Feng CONG, Chaochun ZHANG, Chunjie LI, Guangzhou WANG, Fusuo ZHANG

期刊论文

IMPROVING FERTILIZATION METHODS AND CROPPING SYSTEMS FOR SUSTAINABLE PRODUCTION OF PEARL MILLET () IN

期刊论文

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

期刊论文

AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

期刊论文

SUSTAINABLE SUGARCANE CROPPING IN CHINA

期刊论文

Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

期刊论文

Heating energy savings potential from retrofitting old apartments with an advanced double-skin façadesystem in cold climate

Yeo Beom YOON, Byeongmo SEO, Brian Baewon KOH, Soolyeon CHO

期刊论文

Separation mechanism for double cylinder with shrink fitting system used for ceramics conveying rollers

Wenbin LI, Hiromasa SAKAI, Shota HARADA, Yasushi TAKASE, Nao-Aki NODA

期刊论文

现代建模与优化技术研究——在三江平原井灌水稻节水灌溉系统中的应用

付强

期刊论文

Effects of nano-silicon and common silicon on lead uptake and translocation in two rice cultivars

Jianguo LIU,Hui CAI,Congcong MEI,Mingxin WANG

期刊论文

Stability analysis and optimization of excavation method of double-arch tunnel with an extra-large span

Yiguo XUE, Huimin GONG, Fanmeng KONG, Weimin YANG, Daohong QIU, Binghua ZHOU

期刊论文

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