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NITROGEN USE AND MANAGEMENT IN ORCHARDS AND VEGETABLE FIELDS IN CHINA: CHALLENGES AND SOLUTIONS

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 386-395 doi: 10.15302/J-FASE-2022443

摘要：

● Excessive application of N fertilizers in orchards and vegetable fields (OVFs) in China is particularly common.

关键词： nitrogen fate     nitrogen fertilizer     orchards     vegetable fields    

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Phosphorus supply and management in vegetable production systems in China

Rui WANG, Weiming SHI, Yilin LI

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 348-356 doi: 10.15302/J-FASE-2019277

摘要：

Vegetable production systems involve high rates of chemical and organic fertilizer applications, leading to significant P accumulation in vegetable soils, as well as a decrease in P use efficiency (PUE), which is one of the key limiting factors in vegetable production. This review introduces the vegetable production systems in China and their fertilization status, and analyzes probable causes of overfertilization of vegetable fields. Poorly developed root systems and high P demand have led to the need to maintain much higher available P concentrations in the root zone for regular growth of vegetables, which might necessitate higher phosphate fertilizer input than the plants require. Research on strategies to improve vegetable PUE and the mechanisms of these strategies are summarized in this review. Increasing the P uptake by vegetables by supplying P during the critical growth stage and effectively utilizing the accumulated P by optimizing the C:P ratio in soils can substantially increase PUE. These advances will provide a basis for improving PUE and optimizing phosphate fertilizer applications in vegetable production through regulatory measures. In addition, some policies are recommended that could ensure the safety of vegetables and improve product quality. This review also aims to improve understanding of P cycling in vegetable fields and assist in the development of best practices to manage P reserves globally.

关键词： phosphate fertilizer     phosphorus use efficiency     vegetable production systems     phosphorus management     policy recommendation    

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SUSTAINABLE NITROGEN MANAGEMENT FOR VEGETABLE PRODUCTION IN CHINA

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 373-385 doi: 10.15302/J-FASE-2022455

摘要：

● Sustainable nitrogen management strategies for Chinese vegetable production are summarized.

关键词： enhanced-efficiency nitrogen fertilizer     integrated knowledge and products strategy     nitrogen rate     reactive nitrogen loss     vegetable     yield    

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Simulation of heterogeneous two-phase media using random fields and level sets

George STEFANOU

《结构与土木工程前沿（英文）》 2015年 第9卷 第2期   页码 114-120 doi: 10.1007/s11709-014-0267-5

摘要： The accurate and efficient simulation of random heterogeneous media is important in the framework of modeling and design of complex materials across multiple length scales. It is usually assumed that the morphology of a random microstructure can be described as a non-Gaussian random field that is completely defined by its multivariate distribution. A particular kind of non-Gaussian random fields with great practical importance is that of translation fields resulting from a simple memory-less transformation of an underlying Gaussian field with known second-order statistics. This paper provides a critical examination of existing random field models of heterogeneous two-phase media with emphasis on level-cut random fields which are a special case of translation fields. The case of random level sets, often used to represent the geometry of physical systems, is also examined. Two numerical examples are provided to illustrate the basic features of the different approaches.

关键词： microstructure     random fields     level sets     shape recovery     two-phase media    

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Environmental and economic assessment of vegetable oil production using membrane separation and vapor

Weibin Kong, Qi Miao, Peiyong Qin, Jan Baeyens, Tianwei Tan

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 166-176 doi: 10.1007/s11705-017-1616-4

摘要： Solvent extraction of crude oil from oilseeds is widely applied for its high production capacity and low cost. In this process, solvent recovery and tail gas treatment are usually performed by adsorption, paraffin scrubbing, or even cryogenics (at low tail gas flow rates). Membrane separation, which has a lower energy consumption than these techniques, spans a broad range of admissible concentrations and flow rates, and is moreover easily combined with other techniques. Vapor recompression has potentials to reduce the heat loss in association with distillation and evaporation. In this study, we proved the possibility of combining membrane separation and vapor recompression to improve the conventional vegetable oil production, by both experiments and process simulation. Nearly 73% of energy can be saved in the process of vegetable oil extraction by the novel processing approach. By further environmental assessment, several impact categories show that the optimized process is environmentally sustainable.

关键词： vegetable oil     solvent-extraction     membrane separation     vapor recompression     environmental and economic assessment    

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Advanced biomass materials: progress in the applications for energy, environmental, and emerging fields

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 795-797 doi: 10.1007/s11705-023-2336-6

摘要： Advanced biomass materials: progress in the applications for energy, environmental, and emerging fields

关键词： progress applications energy     fields    

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Engineering Fronts in fields of Energy and Electrical Science and Technologies in the report of

《能源前沿（英文）》 2023年 第17卷 第1期   页码 5-8 doi: 10.1007/s11708-023-0868-6

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The perturbed magnetic fields caused by mechanical stress

QIN Fei, YAN Dong-mei

《机械工程前沿（英文）》 2006年 第1卷 第2期   页码 151-156 doi: 10.1007/s11465-006-0015-1

摘要： In the framework of the linearized magnetoelastic theory, the perturbed magnetic fields caused by mechanical stress and deformation were investigated theoretically. Governing equations and boundary conditions to determine the perturbed fields were derived. The effect of mechanical deformation on the magnetic fields was taken into account by coupling structural displacement into the perturbed magnetic field continuous conditions on the boundary of the structure. As an example, the perturbed field of a half-plane magnetized structure caused by a point force was calculated by the Fourier transform method. The results show that the calculated magnetic intensity component normal to the boundary of the structure reaches its maximum at the point force acted while the component tangent to the boundary inverses its direction sharply. The magnetic induction of the perturbed field is proportional to the applied force. Magnitude analysis proved that since the applied magnetic field has a relative weak intensity such as the Earth s magnetic field, influence of the magnetic field on deformation of the structure can be neglected.
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Stem cell niches and endogenous electric fields in tissue repair

null

《医学前沿（英文）》 2011年 第5卷 第1期   页码 40-44 doi: 10.1007/s11684-011-0108-z

摘要：

Adult stem cells are responsible for homeostasis and repair of many tissues. Endogenous adult stem cells reside in certain regions of organs, known as the stem cell niche, which is recognized to have an important role in regulating tissue maintenance and repair. In wound healing and tissue repair, stem cells are mobilized and recruited to the site of wound, and participate in the repair process. Many regulatory factors are involved in the stem cell-based repair process, including stem cell niches and endogenous wound electric fields, which are present at wound tissues and proved to be important in guiding wound healing. Here we briefly review the role of stem cell niches and endogenous electric fields in tissue repair, and hypothesize that endogenous electric fields become part of stem cell niche in the wound site.

关键词： stem cell     stem cell niche     electric field     tissue repair    

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Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale

Bruno SUDRET,Hung Xuan DANG,Marc BERVEILLER,Asmahana ZEGHADI,Thierry YALAMAS

《结构与土木工程前沿（英文）》 2015年 第9卷 第2期   页码 121-140 doi: 10.1007/s11709-015-0290-1

摘要： The spatial variability of stress fields resulting from polycrystalline aggregate calculations involving random grain geometry and crystal orientations is investigated. A periodogram-based method is proposed to identify the properties of homogeneous Gaussian random fields (power spectral density and related covariance structure). Based on a set of finite element polycrystalline aggregate calculations the properties of the maximal principal stress field are identified. Two cases are considered, using either a fixed or random grain geometry. The stability of the method w.r.t the number of samples and the load level (up to 3.5% macroscopic deformation) is investigated.

关键词： polycrystalline aggregates     crystal plasticity     random fields     spatial variability     correlation structure    

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Extrapolation reconstruction of wind pressure fields on the claddings of high-rise buildings

Yehua SUN, Guquan SONG, Hui LV

《结构与土木工程前沿（英文）》 2019年 第13卷 第3期   页码 653-666 doi: 10.1007/s11709-018-0503-5

摘要： Recent research about reconstruction methods mainly used the interpolation reconstruction of the fluctuating wind pressure field on the surface. However, to investigate wind pressure at the edge of the building, the work presented in this paper focuses on the extrapolation reconstruction of wind pressure fields. Here, we propose an improved proper orthogonal decomposition (POD) and Kriging method with a von Kármán correlation function to resolve this issue. The studies show that it works well for not only interpolation reconstruction but also extrapolation reconstruction. The proposed method does require determination of the Hurst exponent and other parameters analysed from the original data. Hence, the fluctuating wind fields have been characterized by the von Kármán correlation function, as an a priori function. Compared with the cubic spline method and different variogram, preliminary results suggest less time consumption and high efficiency in extrapolation reconstruction at the edge.

关键词： extrapolation reconstruction     proper orthogonal decomposition     Kriging method     von Kármán function     Hurst exponent     rescaled range analysis    

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SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

《农业科学与工程前沿（英文）》 2023年 第10卷 第2期   页码 248-261 doi: 10.15302/J-FASE-2023499

摘要：

● Establishment of a rapid tool for monitoring soil carbon sequestration in farmer fields.

关键词： 4 per 1000 initiative     carbon sequestration     climate action     farmer fields     SDG13     soil organic carbon     soil testing    

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High cadmium pollution risk on vegetable amaranth and a selection for pollution-safe cultivars to lower

Yihui ZHOU, Meng XUE, Zhongyi YANG, Yulian GONG, Jiangang YUAN, Chunyan ZHOU, Baifei HUANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 219-230 doi: 10.1007/s11783-012-0469-9

摘要： A pot experiment was carried out by growing 29 different genotypes ( spp.) of vegetable amaranth under low- (0.12 mg·kg ) and middle- (0.40 mg·kg ) cadmium (Cd) exposure. The result showed that amaranth was vulnerable to cadmium (Cd) contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant ( <0.001) in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated ( <0.01), implying that Cd-accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxingdayemashixian (cv. Nan), a selected typical pollution-safe cultivar (Cd-PSC), and cv. Pennongjianyexian (cv. Pen), a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in F (Cd form extracted by 1 mol·L NaCl) may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.

关键词： Amaranth     Cadmium (Cd)     Cd accumulation     pollution-safe cultivar (PSC)     Cd chemical forms     health risk    

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我国蔬菜种业发展战略研究

王立浩,方智远,杜永臣,徐东辉,张扬勇,杨丽梅,龚一帆,刘富中,庄飞云

《中国工程科学》 2016年 第18卷 第1期   页码 123-136 doi: 10.15302/J-SSCAE-2016.01.015

摘要：

我国是世界第一大蔬菜生产国与消费国，蔬菜种业是确保现代蔬菜产业发展和蔬菜周年均衡供应的重要物质基础。实现蔬菜种业的可持续发展要靠科技创新。我国蔬菜种业发展进入了一个关键的时期。本文分析了我国蔬菜种业与种业科技的现状，对比了国外蔬菜种业发展的情况，针对我国蔬菜种业的主要问题，提出了我国蔬菜种业的发展战略、目标、任务、保障措施和政策建议。

关键词： 蔬菜种业     科技     发展战略    

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化工、冶金与材料领域颠覆性技术影响初探

“化工、冶金与材料领域”课题组

《中国工程科学》 2018年 第20卷 第6期   页码 34-41 doi: 10.15302/J-SSCAE-2018.06.006

摘要：

化工、冶金与材料工业通过获取自然资源进行再加工，生产人类生活所必需的材料、化学品和二次能源，为人类社会发展和国民经济建设提供了重要的物质基础。本文梳理了化工、冶金与材料领域历史上曾产生过的、公认的具有颠覆性意义的技术，分析了这类技术对人们日常生活、人类社会文明进步的影响和对传统技术的颠覆。并根据愿景驱动、问题导向和世界技术发展趋势，对化工、冶金与材料领域未来高效、安全、节能环保的可持续性科学发展模式，以及有望产生的颠覆性技术对国计民生的影响进行了展望，提出了浆态床渣油加氢转化技术、冶金制造流程功能拓展技术、石墨烯等具有颠覆性意义的技术。最后针对颠覆性技术的培育、发展和所需营造的环境提出了相关政策与建议。

关键词： 化工     冶金     材料     颠覆性技术     国计民生    

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标题 作者 时间 类型 操作

NITROGEN USE AND MANAGEMENT IN ORCHARDS AND VEGETABLE FIELDS IN CHINA: CHALLENGES AND SOLUTIONS

期刊论文

Phosphorus supply and management in vegetable production systems in China

Rui WANG, Weiming SHI, Yilin LI

期刊论文

SUSTAINABLE NITROGEN MANAGEMENT FOR VEGETABLE PRODUCTION IN CHINA

期刊论文

Simulation of heterogeneous two-phase media using random fields and level sets

George STEFANOU

期刊论文

Environmental and economic assessment of vegetable oil production using membrane separation and vapor

Weibin Kong, Qi Miao, Peiyong Qin, Jan Baeyens, Tianwei Tan

期刊论文

Advanced biomass materials: progress in the applications for energy, environmental, and emerging fields

期刊论文

Engineering Fronts in fields of Energy and Electrical Science and Technologies in the report of

期刊论文

The perturbed magnetic fields caused by mechanical stress

QIN Fei, YAN Dong-mei

期刊论文

Stem cell niches and endogenous electric fields in tissue repair

null

期刊论文

Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale

Bruno SUDRET,Hung Xuan DANG,Marc BERVEILLER,Asmahana ZEGHADI,Thierry YALAMAS

期刊论文

Extrapolation reconstruction of wind pressure fields on the claddings of high-rise buildings

Yehua SUN, Guquan SONG, Hui LV

期刊论文

SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

期刊论文

High cadmium pollution risk on vegetable amaranth and a selection for pollution-safe cultivars to lower

Yihui ZHOU, Meng XUE, Zhongyi YANG, Yulian GONG, Jiangang YUAN, Chunyan ZHOU, Baifei HUANG

期刊论文

我国蔬菜种业发展战略研究

王立浩,方智远,杜永臣,徐东辉,张扬勇,杨丽梅,龚一帆,刘富中,庄飞云

期刊论文

化工、冶金与材料领域颠覆性技术影响初探

“化工、冶金与材料领域”课题组

期刊论文