资源类型

期刊论文 4

年份

2023 1

2018 2

2008 1

关键词

检索范围:

排序: 展示方式:

Equivalent thermal conductivity of heat pipes

LU Zesheng, MA Binghui

《机械工程前沿(英文)》 2008年 第3卷 第4期   页码 462-466 doi: 10.1007/s11465-008-0087-1

摘要: In precision machining, the machining error from thermal distortion carries a high proportion of the total errors. If a precision machining tool can transfer heat fast, the thermal distortion will be reduced and the machining precision will be improved. A heat pipe working based on phase transitions of the inner working liquid transfers heat with high efficiency and is widely applied in spaceflight and chemical industries. In mechanics, applications of heat pipes are correspondingly less. When a heat pipe is applied to a hydrostatic motorized spindle, the thermal distortion cannot be solved during the heat transfer process because thermal conductivity or equivalent thermal conductivity should be provided first for special application in mechanics. An equivalent thermal conductivity model based on equivalent thermal resistances is established. Performance tests for a screen wick pipe, gravity pipe, and rotation heat pipe are done to validate the efficiency of the equivalent thermal conductivity model. The proposed model provides a calculation method for the thermal distortion analysis of heat pipes applied in the motorized spindle.

关键词: proposed     distortion analysis     hydrostatic motorized     motorized spindle     Performance    

A proposed framework for accelerating technology trajectories in agriculture: a case study in China

Beth CLARK, Glyn D. JONES, Helen KENDALL, James TAYLOR, Yiying CAO, Wenjing LI, Chunjiang ZHAO, Jing CHEN, Guijun YANG, Liping CHEN, Zhenhong LI, Rachel GAULTON, Lynn J. FREWER

《农业科学与工程前沿(英文)》 2018年 第5卷 第4期   页码 485-498 doi: 10.15302/J-FASE-2018244

摘要:

Precision agriculture (PA) technologies have great potential for promoting sustainable intensification of food production, ensuring targeted delivery of agricultural inputs, and hence food security and environmental protection. The benefits of PA technologies are applicable across a broad range of agronomic, environmental and rural socio-economic contexts globally. However, farmer and land-manager adoption in low to middle income countries has typically been slower than that observed in more affluent countries. China is currently engaged in the process of agricultural modernisation to ensure food security for its 1.4 billion population and has developed a portfolio of policies designed to improve food security, while simultaneously promoting environmental protection. Particular attention has been paid to the reduction of agricultural inputs such as fertilisers and pesticides. The widespread adoption of PA technologies across the Chinese agricultural landscape is central to the success of these policies. However, socio-economic and cultural barriers, farm scale, (in particular the prevalence of smaller family farms) and demographic changes in the rural population, (for example, the movement of younger people to the cities) represent barriers to PA adoption across China. A framework for ensuring an acceptable and accelerated PA technology trajectory is proposed which combines systematic understanding of farmer and end-user priorities and preferences for technology design throughout the technology development process, and subsequent end-user requirements for implementation (including demonstration of economic and agronomic benefits, and knowledge transfer). Future research will validate the framework against qualitative and quantitative socio-economic, cultural and agronomic indicators of successful, or otherwise, PA implementation. The results will provide the evidence upon which to develop further policies regarding how to secure sustainable food production and how best to implement PA in China, as well as practical recommendations for optimising end-user uptake.

关键词: precision agriculture     farmer adoption     technological innovation    

PROPOSED INNOVATION REFORM MODEL FOR THE MINERAL NITROGEN FERTILIZER INDUSTRY IN CHINA TO REDUCE GREENHOUSE

《农业科学与工程前沿(英文)》 2023年 第10卷 第2期   页码 234-247 doi: 10.15302/J-FASE-2022468

摘要:

● The carbon footprint of the nitrogen fertilizer chain has decreased significantly over the last decade.

关键词: carbon accounting     life cycle assessment     policy     product structure    

Proposed EU legislation to force changes in sewage sludge disposal: A case study

Vojtěch Turek, Bohuslav Kilkovský, Zdeněk Jegla, Petr Stehlík

《化学科学与工程前沿(英文)》 2018年 第12卷 第4期   页码 660-669 doi: 10.1007/s11705-018-1773-0

摘要:

The consequences of changes planned in the European Union legislation relevant to the disposal of sewage sludges are discussed. A specific municipal waste water treatment plant is analyzed in terms of drying and subsequent combustion or pyrolysis of the produced stabilized sludge, and the respective net energy balances are carried out. A simplified economic analysis of the two disposal options is presented, which suggest that combustion of the sludge would be economically infeasible while pyrolysis of the sludge in a modular, self-sufficient container unit can bring a small financial benefit due to the selling of the produced phosphorus-rich biochar.

关键词: sewage sludge     drying     combustion     pyrolysis    

标题 作者 时间 类型 操作

Equivalent thermal conductivity of heat pipes

LU Zesheng, MA Binghui

期刊论文

A proposed framework for accelerating technology trajectories in agriculture: a case study in China

Beth CLARK, Glyn D. JONES, Helen KENDALL, James TAYLOR, Yiying CAO, Wenjing LI, Chunjiang ZHAO, Jing CHEN, Guijun YANG, Liping CHEN, Zhenhong LI, Rachel GAULTON, Lynn J. FREWER

期刊论文

PROPOSED INNOVATION REFORM MODEL FOR THE MINERAL NITROGEN FERTILIZER INDUSTRY IN CHINA TO REDUCE GREENHOUSE

期刊论文

Proposed EU legislation to force changes in sewage sludge disposal: A case study

Vojtěch Turek, Bohuslav Kilkovský, Zdeněk Jegla, Petr Stehlík

期刊论文