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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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Image analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray CT

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

《结构与土木工程前沿（英文）》 2012年 第6卷 第2期   页码 85-100 doi: 10.1007/s11709-012-0159-5

摘要： The ground subsidence on the underground pipe often is caused with the reduction of the effective stress and the loss of suction in the base course and then, soil drainage into the pipe. The final formation of the cavity growth in the ground was observed as the ground subsidence. Authors focused this problem and hence performed model tests with water-inflow and drainage cycle in the model ground. The mechanism of cavity generation in the model ground was observed using an X-ray Computed Tomography (CT) scanner. In those studies, water was supplied into the model grounds from the defected underground pipe model in case of the change of relative density and grain size distribution. As results, it was observed that the loosening area was generated from the defected part with water-inflow and some of the soil particles in the ground were drained into the underground pipe through the defected part. And afterward, the cavity was generated just above the defected part of the model pipe in the ground. Based on this observation, it might be said that the bulk density of soil around the defected pipe played one of key factor to generate the cavity in the ground. Moreover, the dimension of the defected part should be related to the magnification of the ground subsidence, in particular, crack width on a sewerage pipe and particle size would be the quantitative factor to evaluate the magnification of the ground subsidence. ?In this paper, it was concluded that the low relative density of soil would become the critical factor to cause the fatal failure of model ground if the maximum grain size was close to the dimension of crack width of defective part. The fatal collapse of the ground with high relative density more than 80% would be avoided in a few cycles of water inflow and soil drainage.

关键词： relative density     grain property     model test     road subsidence     underground pipe     image processing     X-ray CT    

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Engineering the grain boundary: a promising strategy to configure NiCoPO/NiCoP nanowire arrays for ultra-stable

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1259-1267 doi: 10.1007/s11705-021-2132-0

摘要： NiCoP4O12/NiCoP nanorod-like arrays with tunable grain boundary density and pores were synthesized by the processes composed of hydrothermal and pyrolysis, in which, the electron structure of Ni and Co atoms characterized by X-ray photoelectron spectroscopy was contemporaneous inverse manipulated. The optimized NiCoP4O12/NiCoP arrays have a high specific capacitance of 507.8 μAh∙cm–2 at 1 mA∙cm–2, and good rate ability of 64.7% retention at 30-folds increased current density. Importantly, an ultra-stable ability, 88.5% of retention after 10000 cycles, was achieved in an asymmetric cell assembled of the NiCoP4O12/NiCoP arrays with activated carbon. In addition, the energy and power densities of an asymmetric cell were higher than those of other work, demonstrating as-prepared NiCoP4O12/NiCoP arrays are promising electrodes for supercapacitors.

关键词： NiCo     array electrode     grain boundary     stability     supercapacitor    

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Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 25-33 doi: 10.15302/J-FASE-2016090

摘要： Reducing irrigation water use by improving water use efficiency (WUE) in grain production is critical for the development of sustainable agriculture in the North China Plain (NCP). This article summarizes the research progresses in WUE improvement carried out at the Luancheng station located in the Northern part of NCP for the past three decades. Progresses in four aspects of yield and WUE improvement are presented, including yield and WUE improvement associated with cultivar selection, irrigation management for improving yield and WUE under limited water supply, managing root system for efficient soil water use and reducing soil evaporation by straw mulch. The results showed that annual average increase of 0.014 kg·m for winter wheat and 0.02 kg·m in WUE were observed for the past three decades, and this increase was largely associated with the improvement in harvest index related to cultivar renewal and an increase in chemical fertilizer use and soil fertility. The results also indicated that deficit irrigation for winter wheat could significantly reduce the irrigation water use, whereas the seasonal yield showed a smaller reduction rate and WUE was significantly improved. Straw mulching of summer maize using the straw from winter wheat could reduce seasonal soil evaporation by 30–40 mm. With new cultivars and improved management practices it was possible to further increase grain production without much increase in water use. Future strategies to further improve WUE are also discussed.

关键词： harvest index     cultivar selection     deficit irrigation     root water uptake     straw mulching    

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Spatiotemporal variation in water footprint of grain production in China

Pute WU,Yubao WANG,Xining ZHAO,Shikun SUN,Jiming JIN

《农业科学与工程前沿（英文）》 2015年 第2卷 第2期   页码 186-193 doi: 10.15302/J-FASE-2015060

摘要： Water shortage has become a significant constraint to grain production in China. A more holistic approach is needed to understand the links between grain production and water consumption. Water footprint provides a framework to assess water utilization in agriculture production. This paper analyzes the spatiotemporal variation in water footprint of grain production (WFGP) in China from 1951 to 2010. The results show that, jointly motivated by the improvement of agricultural production and water use efficiency, WFGP in all areas showed a decreasing trend. National average WFGP has decreased from 3.38 to 1.31 m ·kg . Due to regional differences in agricultural production and water use efficiency, spatial distribution of WFGP varies significantly and its pattern has changed through time. Moreover, WFGP may show significant differences within areas of similar climatic conditions and agricultural practices, indicating that there is a strong need to improve the management of water use technology. Statistical analysis revealed that regional differences in grain yield are the main cause for variations in spatiotemporal WFGP. However, the scope for further increases in grain yield is limited, and thus, the future goal of reducing WFGP is to decrease the water use per unit area.

关键词： water footprint     grain production     grain secu- rity     water scarcity     water-saving    

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Genetic improvement of wheat grain quality at CIMMYT

Carlos GUZMÁN, Karim AMMAR, Velu GOVINDAN, Ravi SINGH

《农业科学与工程前沿（英文）》 2019年 第6卷 第3期   页码 265-272 doi: 10.15302/J-FASE-2019260

摘要：

The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and in farming systems based on these crops. CIMMYT leads the Global Wheat Program (GWP), which includes some of the largest wheat breeding programs in the world. The GWP has been successful in developing wheat germplasm that is used extensively worldwide. Wheat quality improvement is a central component of all the breeding efforts at CIMMYT and the Wheat Chemistry and Quality Laboratory represents an integral part of the breeding programs. Wheat quality is addressed at CIMMYT over the full range of this very wide and variable concept with milling, processing, end-use and nutritional quality targeted. Wheat progenitors and advanced lines developed by the breeders are assessed for diverse quality attributes, with the aim of identifying those that fulfill the requirements in terms of milling, processing, end-use and nutritional quality in different target regions. Significant research is conducted to make more efficient the integration of wheat quality traits in the breeding programs. The main topics being addressed are (1) methodologies to analyze grain quality traits, (2) genetic control and environmental effects on quality traits, (3) characterization of genetic resources for quality improvement, and (4) diversifying grain properties for novel uses.

关键词： biofortification     breeding     grain quality     wheat    

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Transcriptome analysis of wheat grain using RNA-Seq

Liu WEI,Zhihui WU,Yufeng ZHANG,Dandan GUO,Yuzhou XU,Weixia CHEN,Haiying ZHOU,Mingshan YOU,Baoyun LI

《农业科学与工程前沿（英文）》 2014年 第1卷 第3期   页码 214-222 doi: 10.15302/J-FASE-2014024

摘要： With the increase in consumer demand, wheat grain quality improvement has become a focus in China and worldwide. Transcriptome analysis is a powerful approach to research grain traits and elucidate their genetic regulation. In this study, two cDNA libraries from the developing grain and leaf-stem components of bread wheat cultivar, Nongda211, were sequenced using Roche/454 technology. There were 1061274 and 1516564 clean reads generated from grain and leaf-stem, respectively. A total of 61393 high-quality unigenes were obtained with an average length of 1456 bp after assembly. The analysis of the 61393 unigenes involved in the biological processes of the grain showed that there were 7355 differentially expressed genes upregulated in the grain library. Gene ontology enrichment and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that many transcription products and transcription factors associated with carbohydrate and protein metabolism were abundantly expressed in the grain. These results contribute to excavate genes associated with wheat quality and further study how they interact.

关键词： transcriptome analysis     wheat grain     differentially expressed genes     enrichment analysis    

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A computational toolbox for molecular property prediction based on quantum mechanics and quantitativestructure-property relationship

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 152-167 doi: 10.1007/s11705-021-2060-z

摘要： Chemical industry is always seeking opportunities to efficiently and economically convert raw materials to commodity chemicals and higher value-added chemical-based products. The life cycles of chemical products involve the procedures of conceptual product designs, experimental investigations, sustainable manufactures through appropriate chemical processes and waste disposals. During these periods, one of the most important keys is the molecular property prediction models associating molecular structures with product properties. In this paper, a framework combining quantum mechanics and quantitative structure-property relationship is established for fast molecular property predictions, such as activity coefficient, and so forth. The workflow of framework consists of three steps. In the first step, a database is created for collections of basic molecular information; in the second step, quantum mechanics-based calculations are performed to predict quantum mechanics-based/derived molecular properties (pseudo experimental data), which are stored in a database and further provided for the developments of quantitative structure-property relationship methods for fast predictions of properties in the third step. The whole framework has been carried out within a molecular property prediction toolbox. Two case studies highlighting different aspects of the toolbox involving the predictions of heats of reaction and solid-liquid phase equilibriums are presented.

关键词： molecular property     quantum mechanics     quantitative structure-property relationship     heat of reaction     solid-liquid phase equilibrium    

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Characterization of grain cadmium concentration in indica hybrid rice

Kai WANG, Qunfeng ZHOU, Tianze YAN, Shilong XU, Longyi ZHAO, Weicheng WANG, Zhigang JIN, Peng QIN, Chenjian FU, Liangbi CHEN, Yuanzhu YANG

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 523-529 doi: 10.15302/J-FASE-2019281

摘要：

As a consequence of contamination of soil with heavy metals, cadmium accumulation in grain is of great concern worldwide, but especially in southern China. It is important to evaluate the Cd accumulation potential of grain before or when examining and approving new cultivars. An evaluation method and criteria for verifying Cd accumulation potential in rice are proposed, and the Cd accumulation potential of 56 mid-season hybrids collected from the provincial cultivar trials in 2016 were investigated. Genotype, environment and their interactions strongly affected the variation in grain Cd accumulation. Two hybrids were identified as slightly Cd accumulating. Hybrids with slight Cd accumulation potential would be suitable for safe grain production on polluted land (total Cd under 2.0 mg·kg ) in Hunan Province (China) and should be considered for new cultivar evaluation and approval. This evaluation method and criterion could be applied for certifying Cd accumulation potential of rice cultivars.

关键词： accumulation     cadmium     hybrid     methodology     rice    

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Mechanical properties of rock materials with related to mineralogical characteristics and grain size

Wenjuan SUN, Linbing WANG, Yaqiong WANG

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 322-328 doi: 10.1007/s11709-017-0387-9

摘要： Mechanical properties of rock materials are related to textural characteristics. The relationships between mechanical properties and textural characteristics have been extensively investigated for differently types of rocks through experimental tests. Based on the experimental test data, single- and multiple- variant regression analyses are conducted among mechanical properties and textural characteristics. Textural characteristics of rock materials are influenced by the following factors: mineral composition, size, shape, and spatial distribution of mineral grains, porosity, and inherent microcracks. This study focuses on the first two: mineral composition and grain size. ? This study comprehensively summarizes the regression equations between mechanical properties and mineral content and the regression equations between mechanical properties and grain size. Further research directions are suggested at the end of this study.

关键词： Mechanical properties     rock material     texture     mineral characteristics    

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Convective heat transfer in helical coils for constant-property and variable-property flows with high

Yufei MAO, Liejin GUO, Bofeng BAI, Ximin ZHANG

《能源前沿（英文）》 2010年 第4卷 第4期   页码 546-552 doi: 10.1007/s11708-010-0116-8

摘要： Forced convection heat transfer of single-phase water in helical coils was experimentally studied. The testing section was constructed from a stainless steel round tube with an inner diameter of 10 mm, coil diameter of 300 mm, and pitch of 50 mm. The experiments were conducted over a wide Reynolds number range of 40000 to 500000. Both constant-property flows at normal pressure and variable-property flows at supercritical pressure were investigated. The contribution of secondary flow in the helical coil to heat transfer was gradually suppressed with increasing Reynolds number. Hence, heat transfer coefficients of the helical tube were close to those of the straight tube under the same flow conditions when the Reynolds number is large enough. Based on the experimental data, heat transfer correlations for both incompressible flows and supercritical fluid flows through helical coils were proposed.

关键词： convective heat transfer     helical coils     high Reynolds number     supercritical pressure     variable property    

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A review on the application of nanofluids in enhanced oil recovery

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1165-1197 doi: 10.1007/s11705-021-2120-4

摘要： Enhanced oil recovery (EOR) has been widely used to recover residual oil after the primary or secondary oil recovery processes. Compared to conventional methods, chemical EOR has demonstrated high oil recovery and low operational costs. Nanofluids have received extensive attention owing to their advantages of low cost, high oil recovery, and wide applicability. In recent years, nanofluids have been widely used in EOR processes. Moreover, several studies have focused on the role of nanofluids in the nanofluid EOR (N-EOR) process. However, the mechanisms related to N-EOR are unclear, and several of the mechanisms established are chaotic and contradictory. This review was conducted by considering heavy oil molecules/particle/surface micromechanics; nanofluid-assisted EOR methods; multiscale, multiphase pore/core displacement experiments; and multiphase flow fluid-solid coupling simulations. Nanofluids can alter the wettability of minerals (particle/surface micromechanics), oil/water interfacial tension (heavy oil molecules/water micromechanics), and structural disjoining pressure (heavy oil molecules/particle/surface micromechanics). They can also cause viscosity reduction (micromechanics of heavy oil molecules). Nanofoam technology, nanoemulsion technology, and injected fluids were used during the EOR process. The mechanism of N-EOR is based on the nanoparticle adsorption effect. Nanoparticles can be adsorbed on mineral surfaces and alter the wettability of minerals from oil-wet to water-wet conditions. Nanoparticles can also be adsorbed on the oil/water surface, which alters the oil/water interfacial tension, resulting in the formation of emulsions. Asphaltenes are also adsorbed on the surface of nanoparticles, which reduces the asphaltene content in heavy oil, resulting in a decrease in the viscosity of oil, which helps in oil recovery. In previous studies, most researchers only focused on the results, and the nanoparticle adsorption properties have been ignored. This review presents the relationship between the adsorption properties of nanoparticles and the N-EOR mechanisms. The nanofluid behaviour during a multiphase core displacement process is also discussed, and the corresponding simulation is analysed. Finally, potential mechanisms and future directions of N-EOR are proposed. The findings of this study can further the understanding of N-EOR mechanisms from the perspective of heavy oil molecules/particle/surface micromechanics, as well as clarify the role of nanofluids in multiphase core displacement experiments and simulations. This review also presents limitations and bottlenecks, guiding researchers to develop methods to synthesise novel nanoparticles and conduct further research.

关键词： nanofluid     EOR mechanism     nanoparticle adsorption     interface property     internal property    

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700 °C 及以上蒸汽温度下先进USC发电厂用耐热材料的研究和开发 Review

Fujio Abe

《工程（英文）》 2015年 第1卷 第2期   页码 211-224 doi: 10.15302/J-ENG-2015031

摘要：

欧洲、美国、日本已开展蒸汽温度为700 °C 及以上的先进超超临界(A-USC) 发电厂用材料开发项目，以实现更高能效和低二氧化碳排放量。近年来中国、印度等也开展了上述项目的开发和研究。这些项目涉及采用镍基合金更换马氏体9%~12%Cr 钢以用于最高温度的锅炉和涡轮部件，从而在700 °C 及以上温度下提供充足的蠕变强度。为尽量减少对昂贵的镍基合金的需求，马氏体9%~12%Cr 钢可用于A-USC 电厂中的次高温部件(最高温度不超过650 °C)。本文综述了A-USC 电厂厚型材锅炉和涡轮部件用镍基合金和马氏体9%~12%Cr 钢的研究和开发，主要关注高温下基底金属和焊缝的长期蠕变断裂强度、焊缝强度损失、蠕变疲劳性质和显微结构演化。

关键词： 镍基合金     9 %~12 % Cr 钢     蠕变强度     蠕变疲劳性质     焊缝     晶界     显微结构     &gamma     &prime     M23C6 碳化物    

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移动式颗粒床除尘器的设计研究

吕保和

《中国工程科学》 2007年 第9卷 第10期   页码 45-48

摘要：

分析了移动式颗粒床除尘器的特点，并与传统除尘器进行了比较。结合理论计算与实际运行试验，提出了移动式颗粒床除尘器主要结构参数及主要性能参数的设计计算方法，证明了该方法具有较好的实际应用价值。

关键词： 移动式颗粒床     除尘器     结构参数     性能参数    

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A solar assisted heat pump drying system for grain in-store drying

Haifeng LI, Yanjun DAI, Jianguo DAI, Xibo WANG, Lei WEI,

《能源前沿（英文）》 2010年 第4卷 第3期   页码 386-391 doi: 10.1007/s11708-010-0003-3

摘要： For grain in-store drying, a solar assisted drying process has been developed, which consists of a set including a solar-assisted heat pump, a ventilation system, a grain stirrer, etc. In this way, low power consumption, short cycle time and water content uniformity can be achieved in comparison with the conventional method. A solar-assisted heat pump drying system has been designed and manufactured for a practical granary, and the energy consumption performance of the unit is analyzed. The analysis result shows that the solar fraction of the unit is higher than 20%, the coefficient of performance about system (COP) is 5.19, and the specific moisture extraction rate (SMER) can reach 3.05 kg/kWh.

关键词： solar energy     heat pump     airflow     in-store drying    

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标题 作者 时间 类型 操作

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

Jianchang YANG

期刊论文

Image analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray CT

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

期刊论文

Engineering the grain boundary: a promising strategy to configure NiCoPO/NiCoP nanowire arrays for ultra-stable

期刊论文

Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

期刊论文

Spatiotemporal variation in water footprint of grain production in China

Pute WU,Yubao WANG,Xining ZHAO,Shikun SUN,Jiming JIN

期刊论文

Genetic improvement of wheat grain quality at CIMMYT

Carlos GUZMÁN, Karim AMMAR, Velu GOVINDAN, Ravi SINGH

期刊论文

Transcriptome analysis of wheat grain using RNA-Seq

Liu WEI,Zhihui WU,Yufeng ZHANG,Dandan GUO,Yuzhou XU,Weixia CHEN,Haiying ZHOU,Mingshan YOU,Baoyun LI

期刊论文

A computational toolbox for molecular property prediction based on quantum mechanics and quantitativestructure-property relationship

期刊论文

Characterization of grain cadmium concentration in indica hybrid rice

Kai WANG, Qunfeng ZHOU, Tianze YAN, Shilong XU, Longyi ZHAO, Weicheng WANG, Zhigang JIN, Peng QIN, Chenjian FU, Liangbi CHEN, Yuanzhu YANG

期刊论文

Mechanical properties of rock materials with related to mineralogical characteristics and grain size

Wenjuan SUN, Linbing WANG, Yaqiong WANG

期刊论文

Convective heat transfer in helical coils for constant-property and variable-property flows with high

Yufei MAO, Liejin GUO, Bofeng BAI, Ximin ZHANG

期刊论文

A review on the application of nanofluids in enhanced oil recovery

期刊论文

700 °C 及以上蒸汽温度下先进USC发电厂用耐热材料的研究和开发

Fujio Abe

期刊论文

移动式颗粒床除尘器的设计研究

吕保和

期刊论文

A solar assisted heat pump drying system for grain in-store drying

Haifeng LI, Yanjun DAI, Jianguo DAI, Xibo WANG, Lei WEI,

期刊论文