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LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

《农业科学与工程前沿(英文)》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE -2020349

摘要:

Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

 

关键词: crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

《农业科学与工程前沿(英文)》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE-2020349

摘要: Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

关键词: crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

Effect of land-use management systems on coupled physical and mechanical, chemical and biological soilprocesses: how can we maintain and predict soil properties and functions?

Rainer HORN, Winfried E. H. BLUM

《农业科学与工程前沿(英文)》 2020年 第7卷 第3期   页码 243-245 doi: 10.15302/J-FASE-2020334

Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1209-1221 doi: 10.1007/s11709-021-0764-2

摘要: Mechanically stabilized earth (MSE) retaining walls are popular for highway bridge structures. They have precast concrete panels attached to earth reinforcement. The panels are designed to have some lateral movement. However, in some cases, excessive movement and even complete dislocation of the panels have been observed. In this study, 3-D numerical modeling involving an existing MSE wall was undertaken to investigate various wall parameters. The effects of pore pressure, soil cohesion, earth reinforcement type and length, breakage/slippage of reinforcement and concrete strength, were examined. Results showed that the wall movement is affected by soil pore pressure and reinforcement integrity and length, and unaffected by concrete strength. Soil cohesion has a minor effect, while the movement increased by 13–20 mm for flexible geogrid reinforced walls compared with the steel grid walls. The steel grid stresses were below yielding, while the geogrid experienced significant stresses without rupture. Geogrid reinforcement may be used taking account of slippage resistance and wall movement. If steel grid is used, non-cohesive soil is recommended to minimize corrosion. Proper soil drainage is important for control of pore pressure.

关键词: mechanically stabilized earth walls     precast concrete panels     backfill soil     finite element modeling     earth reinforcement    

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 99-116 doi: 10.1007/s11709-021-0799-4

摘要: In this study, bituminous binder was modified with Cocamide Diethanolamide chemical, a non-ionic surfactant, and the physical and rheological properties of modified binders were investigated. In addition, Cocamide Diethanolamide has been used for the first time to modify bituminous binder, and this situation makes the study distinctive. Bituminous binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios (1%, 3%, and 5%). The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests (softening point, penetration, ductility) and Superpave tests (rotational viscometer, rolling thin film oven test, pressure aging vessel, dynamic shear rheometer, bending beam rheometer). In addition, the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing temperatures. In addition, compared to reference binder, rutting resistances of modified bituminous binders decreased with the increase of additive ratio. However, modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

关键词: Cocamide Diethanolamide     bitumen modification     rheology     Superpave tests    

Influence of the sewage irrigation on the agricultural soil properties in Tongliao City, China

Hong YAO, Shichao ZHANG, Xiaobo XUE, Jie YANG, Kelin HU, Xiaohua YU

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 273-280 doi: 10.1007/s11783-013-0497-0

摘要: Increasing shortages of fresh water has led to greater use of treated wastewater for irrigation of crops. This study evaluates the spatial variability of soil properties after irrigation with wastewater and freshwater. Geostatistical techniques were used to identify the variability of soil properties at the different sites. A set of physical and chemical soil properties were measured including total nitrogen (TN), total phosphorus (TP), organic matter (OM) and soil moisture. The TN concentration levels varied from 567 to 700 mg·kg , while OC levels ranged from 7.3 to 16.3 mg·kg in wastewater-irrigated zones. The concentration levels of TP were between 371.53 and 402.88 mg·kg for the wastewater-irrigated sites. Wastewater irrigation resulted in higher TN, TP and OM concentrations by 18.4%, 8% and 25%, respectively. The highest TN and OM occurred along the wastewater trunk. It was also observed that nitrogen concentrations correlate with the soil's organic matter. The increase of salinity may be associated with the increase of pH, which might suggest that a reduction of pH will be beneficial for plant growth due to the decrease of salinity. The average concentrations of nitrogen in topsoil were higher than those in subsurface soils in irrigated areas. Such differences of the N profile might be due to variations in organic matter content and microbial populations. Consistent with TN and OM, soil C:N decreased significantly with an increase of depth. This phenomenon possibly reflects a greater degree of breakdown and the older age of humus stored in the deeper soil layers. The analysis of pH levels at different depths for the three sites showed that pH values for wastewater irrigation were slightly lower than the controlled sites at the same depths.

关键词: spatial variability     soil properties     groundwater and sewage irrigation    

Effects of different types of biochar on the properties and reactivity of nano zero-valent iron in soil

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-021-1388-4

摘要:

• Biochar enhanced the mobility and stability of zero-valent iron nanoparticles.

关键词: Nano zero-valent iron     Biochar     BDE209     Transport     Soil    

Growth and properties analysis of metal-organic chemical vapor deposited MgZnO films on -AlO substrates

SHI Zengliang, LIU Dali, YAN Xiaolong, GAO Zhongmin, BAI Shiying

《机械工程前沿(英文)》 2008年 第3卷 第3期   页码 261-264 doi: 10.1007/s11465-008-0036-z

摘要: MgZnO (0 < ? 0.12) thin films with the wurtzite structure have been successfully grown on -AlO substrates by metal-organic chemical vapor deposition (MOCVD). X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), photoluminescence (PL) spectrometry, and transmission measurements are performed to study the characteristics of MgZnO thin films. Results show that with increasing Mg content, the diffraction peak of MgZnO thin films shifts towards a higher diffraction angle (the biggest shift is 0.22°), and the full width at half maximum (FWHM) of the diffraction peak is broadened. Meanwhile, a blue-shift occurs at the near-band-edge (NBE) emission peak and the largest blue-shift of the band gap of the MgZnO films is 113 meV with Mg content = 0.12. Therefore, the energy band gap of the MgZnO films is determined by Mg content in the thin films and the energy band gap increases with an increase of Mg content.

关键词: increase     photoelectron spectroscopy     transmission     wurtzite structure     MgZnO    

Using a systems modeling approach to improve soil management and soil quality

Enli WANG, Di HE, Zhigan ZHAO, Chris J. SMITH, Ben C. T. MACDONALD

《农业科学与工程前沿(英文)》 2020年 第7卷 第3期   页码 289-295 doi: 10.15302/J-FASE-2020337

摘要:

Soils provide the structural support, water and nutrients for plants in nature and are considered to be the foundation of agriculture production. Improving soil quality and soil health has been advocated as the goal of soil management toward sustainable agricultural intensification. There have been renewed efforts to define and quantify soil quality and soil health but establishing a consensus on the key indicators remains difficult. It is argued that such difficulties are due to the former ways of thinking in soil management which largely focus on soil properties alone. A systems approach that treats soils as a key component of agricultural production systems is promoted. It is argued that soil quality must be quantified in terms of crop productivity and impacts on ecosystems services that are also strongly driven by climate and management interventions. A systems modeling approach captures the interactions among climate, soil, crops and management, and their impacts on system performance, thus helping to quantify the value and quality of soils. Here, three examples are presented to demonstrate this. In this systems context, soil management must be an integral part of systems management practices that also include managing the crops and cropping systems under specific climatic conditions, with cognizance of future climate change.

关键词: APSIM     available water capacity     nitrogen management     soil functional properties     soil health     soil-plant modeling    

Chemical additives affect sulfate reducing bacteria biofilm properties adsorbed on stainless steel 316L

Yu Qi,Jin Li,Rui Liang,Sitong Ji,Jianxiang Li,Meng Liu

《环境科学与工程前沿(英文)》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0917-7

摘要: There are more polysaccharides than proteins in EPS on SS316L surface. NaClO cuts down more protein, while 1227 reduced more polysaccharides in EPS. HEDP slightly eased the corrosion, NaClO and 1227 inhibited the microbial corrosion. NaClO still performed pitting corrosion properties to some extent. 1227 changed the C:O and NaClO decreased the amidogen in SS316L surface film. This paper studied the biofilm properties and corrosion behavior of sulfate reducing bacteria (SRB) on stainless steel 316L (SS316L) surface in circulating cooling water system with and without additives including hydroxy ethyl fork phosphonic acid (HEDP), dodecyl dimethyl benzyl ammonium chlotide (1227) and NaClO. Biochemical technique, electrochemical technology, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used. The results show that the extracellular polymeric substance (EPS) in biofilm attached on the SS316L surface mainly contain proteins and polysaccharides, the contents are 98 ug·cm and 635ug·cm , respectively. The polysaccharides were cut by 1227 about 80%, while 55% by NaClO. The proteins were reduced by NaClO about 53%, while only 30% by 1227. The potentiodynamic polarization shows that the corrosion potential of SS316L was enhanced from −0.495 V to −0.390 V by the chemical additives, delaying the occurrence of the corrosion. And the corrosion rate was also reduced from 5.19 × 10 mm·a to 2.42 × 10 mm·a . But NaClO still caused pitting corrosion after sterilizing the bacteria, while 1227 can form a protective film on the surface of SS316L. Though HEDP contribute to the bacteria activity, it can enhance the breakdown potential. XPS results confirmed that 1227 can change the value of C:O in the biofilm attached on metal surface, and NaClO can eliminate the existence of amidogen. This study would provide some recommendations for the selection of chemical additives in the thermal power plant.

关键词: Sulfate reducing bacteria (SRB)     Chemical additives     Biofilm     Extracellular polymeric substance (EPS)     Microbe Corrosion    

极端条件下材料化学和输运性质的第一原理研究 Review

John S. Tse

《工程(英文)》 2019年 第5卷 第3期   页码 421-433 doi: 10.1016/j.eng.2019.01.008

摘要:

地球是一个动态系统。从常温常压到地核的360 GPa 和6600 K,地球的热力学状态随着深度的变化而发生很大变化。因此,地球成分(如硅酸盐和碳酸盐矿物)的物理和化学性质受其所处环境的显著影响。在过去的30 年中,在极端条件下的材料表征的实验技术和理论模拟方法都取得了巨大的进步。这些进步提升了我们对矿物特性的理解,这对于充分认识这个星球的形成及其生命起源至关重要。本文回顾了用于预测极端条件下材料性质的最新计算技术,本研究仅限于应用第一原理分子动力学(first principle molecular dynamics, FPMD)方法研究与地球科学相关的化学和热力学输运过程。

关键词: 高压     高温     地幔     分子动力学     密度泛函方法     输运性质     化学反应    

Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 167-171 doi: 10.1007/s11705-007-0031-7

摘要: The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/AlO catalysts for the partial oxidation of methane to syngas were studied by means of BET, XRD, H-TPR, TEM and performance evaluation. It was found that the MgO promoter benefited from the uniformity of nickel species in the catalysts, inhibited the formation of NiAlO spinel and improved the interaction between nickel species and support. These results were related to the formation of NiO MgO solid solution and MgAlO spinel. Moreover, for the catalysts with a proper amount of MgO promoter, the nickel dispersiveness was enhanced, therefore making their catalytic performance in methane partial oxidation improved. However, the excessive MgO promoter exerted a negative effect on the catalytic performance. Meanwhile, the basicity of MgO promoted the reversed water gas shift reaction, which led to an increase in CO selectivity and a decrease in H2 selectivity. The suitable content of MgO promoter in Ni/AlO catalyst was ?7 wt-%.

关键词: excessive     selectivity     decrease     dispersiveness     physico-chemical    

静电自组装制备复合磨粒及其对铜的抛光特性研究

黄亦申,许雪峰,姚春燕,胡建德,彭伟

《中国工程科学》 2012年 第14卷 第10期   页码 82-89

摘要:

研究苯代三聚氰胺甲醛(BGF)微球与阳离子型聚电解质聚二烯丙基二甲基氯化铵(PDADMAC)、阴离子型聚电解质聚4-苯乙烯璜酸钠(PSS)之间的吸附特性,利用静电自组装技术改变和控制BGF微球的荷电特性,制备出不同形式的PEi BGF/SiO2复合磨粒,以Zeta电位、透射电子显微镜(TEM)和热重分析(TG)等手段对复合磨粒进行了表征,并利用这些复合磨粒制备了铜片抛光用的复合磨粒抛光液。抛光试验表明,吸附在聚合物微球表面和游离于抛光液中的SiO2磨粒在抛光中均起到材料去除作用。传统单一SiO2磨粒抛光液的铜材料去除率为264 nm/min,PE0 BGF/SiO2混合磨粒抛光液的铜材料去除率为348 nm/min,PE3 BGF/SiO2复合磨粒抛光液的铜材料去除率为476 nm/min。经上述3种抛光液抛光后的铜表面,在5 μm×5 μm范围内,表面粗糙度Ra从0.166 μm分别降至3.7 nm、2.6 nm和1.5 nm,峰谷值Rpv分别小于20 nm、14 nm和10 nm,复合磨粒抛光液对铜片有良好的抛光性能。

关键词: 化学机械抛光     抛光液     复合磨粒     聚电解质     铜片    

Self-propelled automatic chassis of Lunokhod-1: History of creation in episodes

Mikhail MALENKOV

《机械工程前沿(英文)》 2016年 第11卷 第1期   页码 60-86 doi: 10.1007/s11465-016-0370-5

摘要:

This report reviews the most important episodes in the history of designing the self-propelled automatic chassis of the first mobile extraterrestrial vehicle in the world, Lunokhod-1. The review considers the issues in designing moon rovers, their essential features, and the particular construction properties of their systems, mechanisms, units, and assemblies. It presents the results of exploiting the chassis of Lunokhod-1 and Lunokhod-2. Analysis of the approaches utilized and engineering solutions reveals their value as well as the consequences of certain defects.

关键词: moon rover     self-propelled chassis     propulsion     wheel     suspension     soil properties     cross-country ability    

植物氯素营养与含氯化肥科学施用

毛知耘,周则芳,石孝均,刘洪斌

《中国工程科学》 2000年 第2卷 第6期   页码 64-66

摘要:

文章主要概述了植物的氯素营养及科学施用含氯化肥三准则。

关键词: 植物氯营养     耐氯力类型     含氯化肥    

标题 作者 时间 类型 操作

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

期刊论文

Effect of land-use management systems on coupled physical and mechanical, chemical and biological soilprocesses: how can we maintain and predict soil properties and functions?

Rainer HORN, Winfried E. H. BLUM

期刊论文

Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

期刊论文

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

期刊论文

Influence of the sewage irrigation on the agricultural soil properties in Tongliao City, China

Hong YAO, Shichao ZHANG, Xiaobo XUE, Jie YANG, Kelin HU, Xiaohua YU

期刊论文

Effects of different types of biochar on the properties and reactivity of nano zero-valent iron in soil

期刊论文

Growth and properties analysis of metal-organic chemical vapor deposited MgZnO films on -AlO substrates

SHI Zengliang, LIU Dali, YAN Xiaolong, GAO Zhongmin, BAI Shiying

期刊论文

Using a systems modeling approach to improve soil management and soil quality

Enli WANG, Di HE, Zhigan ZHAO, Chris J. SMITH, Ben C. T. MACDONALD

期刊论文

Chemical additives affect sulfate reducing bacteria biofilm properties adsorbed on stainless steel 316L

Yu Qi,Jin Li,Rui Liang,Sitong Ji,Jianxiang Li,Meng Liu

期刊论文

极端条件下材料化学和输运性质的第一原理研究

John S. Tse

期刊论文

Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

期刊论文

静电自组装制备复合磨粒及其对铜的抛光特性研究

黄亦申,许雪峰,姚春燕,胡建德,彭伟

期刊论文

Self-propelled automatic chassis of Lunokhod-1: History of creation in episodes

Mikhail MALENKOV

期刊论文

植物氯素营养与含氯化肥科学施用

毛知耘,周则芳,石孝均,刘洪斌

期刊论文