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EFFECTS OF SUBSTITUTION OF MINERAL NITROGEN WITH ORGANIC AMENDMENTS ON NITROGEN LOSS FROM SLOPING CROPLAND

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 396-406 doi: 10.15302/J-FASE-2022456

摘要：

● Interflow acts as the dominant pathway for N loss loadings.

关键词： improved fertilization regime     interflow     nitrogen forms     nitrogen leaching     purple soil     sloping cropland    

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Unnormalized and normalized forms of gefura measures in directed and undirected networks

Raf GUNS,Ronald ROUSSEAU

《信息与电子工程前沿（英文）》 2015年 第16卷 第4期   页码 311-320 doi: 10.1631/FITEE.1400425

摘要： In some networks nodes belong to predefined groups (e.g., authors belong to institutions). Common network centrality measures do not take this structure into account. Gefura measures are designed as indicators of a node’s brokerage role between such groups. They are defined as variants of betweenness centrality and consider to what extent a node belongs to shortest paths between nodes from different groups. In this article we make the following new contributions to their study: (1) We systematically study unnormalized gefura measures and show that, next to the ‘structural’ normalization that has hitherto been applied, a ‘basic’ normalization procedure is possible. While the former normalizes at the level of groups, the latter normalizes at the level of nodes. (2) Treating undirected networks as equivalent to symmetric directed networks, we expand the definition of gefura measures to the directed case. (3) It is shown how Brandes’ algorithm for betweenness centrality can be adjusted to cover these cases.

关键词： Networks subdivided in groups     Partitions     Gefura measures     Q-measures     Brokerage role     Directed and undirected networks     Brandes’     algorithm    

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Spatial distribution of phosphorus forms in sediments with different distances to the estuary of the

Shaoyong LU, Xiangcan JIN, Fengchang WU, Jing SI, Jianning GUO,

《环境科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 295-300 doi: 10.1007/s11783-010-0231-0

摘要： Effects of human activity on the distribution of phosphorus (P) forms were investigated for the sediments and porewaters in Daqinghe Estuary of Dianchi Lake, China. The concentrations of total P (TP), inorganic-P (I-P), and organic-P (Org-P), and the ratio of iron-bound P (Fe-P)/calcium-bound P (Ca-P) in the sediments decreased with the increasing distance from the sampling site to the estuary. This is probably due to the flocculant materials, e.g., ferric and aluminous salts, usually being added in the wastewater treatment processes. The concentration of ammonia in the sediment porewaters significantly decreased with the increasing distance from the sampling site to the estuary. Both concentrations of total nitrogen and nitrogen in the sediment porewaters decreased to some content with the increasing distance from the sampling site to the estuary. However, the concentrations of nitrate, dissolved total P (DTP), and TP did not have strong relationship with the distances from the sampling sites to the estuary. Pollution load and water quantity also had an important influence on the concentrations of P in sediments and its interstitial water in estuary sedimentary area.

关键词： estuary sedimentary area     phosphorus (P)     spatial distribution     human activity     the Dianchi Lake    

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Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments

Hongguang CHENG,Xiao PU,Yiting CHEN,Fanghua HAO,Liming DONG

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 905-921 doi: 10.1007/s11783-014-0650-4

摘要： Variations of phosphorus (P) and its species in surface sediment of Baiyangdian Lake, a eutrophic shallow lake located in North China, were investigated through combination of field survey and numerical calculation based on cluster analysis. P fractionation was performed by a sequential extraction scheme, categorized as loosely bound P (NH Cl-P), reductant soluble P (BD-P), metallic oxide bound P (NaOH-P), calcium bound P (HCl-P) and organic P (Org-P). P concentrations exhibited regional similarities and a total of four sub-areas were identified in which the same rank was HCl-P>Org-P>BD-P ≈ NaOH-P>NH Cl-P. NH Cl-P, BD-P and Org-P were found to contribute to P enrichment in overlying water column. Specifically, labile Org-P acted as a potential pool with a greater contribution in aerobic layer compared to anaerobic layer. A hysteresis (lag= 4 months) existed when labile Org-P concentration was negatively correlated with aerobic layer thickness. In view of magnitude of identified P contributors in sub-areas, higher potential of P release was present in Fuhe River and Tang River estuary areas. On the basis of calibration and verification, the mathematical model with parameter settings applied in this study was improved to serve as a tool for limnology management and eutrophic control.

关键词： phosphorus fractionation     variation characteristics     modeling     sediment     Baiyangdian Lake    

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SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 366-372 doi: 10.15302/J-FASE-2022447

摘要：

● There is huge potential for improvement of nitrogen management in Australia.

关键词： Australian agroecosystems     reactive nitrogen     sustainable development    

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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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Micro/nanofluidics-enabled energy conversion and its implemented devices

Yang YANG, Jing LIU

《能源前沿（英文）》 2011年 第5卷 第3期   页码 270-287 doi: 10.1007/s11708-010-0126-6

摘要： Most people were not aware of the role of energy as a basic force that drives the development and economic growth of the world until the two great oil crises occurred. According to the conservation law, energy not only exists in various forms but is also capable of being converted from one form to another. The common forms of energy are mechanical energy, chemical energy, internal energy, electrical energy, atomic energy, and electromagnetic energy, among others. The fluids in nature serve as the most common carriers and media in the energy conversion process. Following the rapid development of microelectromechanical systems (MEMS) technology, the energy supply and conversion issue in micro/nano scale has also been introduced in research laboratories worldwide. With unremitting efforts, great quantities of micro/nano scale energy devices have been investigated. Micro/nanofluid shows distinct features in transporting and converting energy similar to their counterpart macroscale tasks. In this paper, a series of micro/nanofluid-enabled energy conversion devices is reviewed based on the transformation between different forms of energy. The evaluation and contradistinction of their performances are also examined. The role of micro/nanofluid as media in micro/nano energy devices is summarized. This contributes to the establishment of a comprehensive and systematic structure in the relationship between energy conversion and fluid in the micro/nano scale. Some fundamental and practical issues are outlined, and the prospects in this challenging area are explored.

关键词： micro/nanofluid     different energy forms     energy conversion     medium role    

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Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 985-995 doi: 10.1007/s11705-021-2126-y

摘要： The high contents of nitrogen-containing organic compounds in biocrude obtained from hydrothermal liquefaction of microalgae are one of the most concerned issues on the applications and environment. In the project, Chlorella sp. and Spirulina sp. were selected as raw materials to investigate the influence of different reaction conditions (i.e., reaction temperature, residence time, solid loading rate) on the distribution of nitrogen in the oil phase and aqueous phase. Three main forms of nitrogen-containing organic compounds including nitrogen-heterocyclic compounds, amide, and amine were detected in biocrudes. The contents of nitrogen-heterocyclic compounds decreased with temperature while amide kept increasing. The effect of residence time on the components of nitrogen-containing organic compounds was similar with that of temperature. However, the influence of solid loading rate was insignificant. Moreover, it was also found that the differences of amino acids in the protein components in the two microalgae might affect the nitrogen distribution in products. For example, nitrogen in basic amino acids of Spirulina sp. preferred to go into the aqueous phase comparing with the nitrogen in neutral amino acids of Chlorella sp. In summary, a brief reaction map was proposed to describe the nitrogen pathway during microalgae hydrothermal liquefaction.

关键词： microalgae     hydrothermal liquefaction     biocrude     nitrogen distribution    

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SOIL NITROGEN CYCLING AND ENVIRONMENTAL IMPACTS IN THE SUBTROPICAL HILLY REGION OF CHINA: EVIDENCE FROM

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 407-424 doi: 10.15302/J-FASE-2022448

摘要：

● Soil nitrogen fluxes and influencing factors were reviewed in the subtropical hilly regions.

关键词： nitrogen cycling     soil nitrogen     nitrogen deposition     greenhouse gases emission     non-point source pollution     nitrogen use efficiency    

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PROGRESS ON IMPROVING AGRICULTURAL NITROGEN USE EFFICIENCY: UK-CHINA VIRTUAL JOINT CENTERS ON NITROGEN

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 475-489 doi: 10.15302/J-FASE-2022459

摘要：

● Virtual joint centers on N agronomy were established between UK and China.

关键词： CINAg     N-CIRCLE     nitrogen use efficiency     reactive nitrogen     sustainable production    

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IMPROVING NITROGEN SAFETY IN CHINA: NITROGEN FLOWS, POLLUTION AND CONTROL

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 465-474 doi: 10.15302/J-FASE-2022454

摘要：

● It is necessary to address the N flows and their impacts on environment in China for sustainable N management.

关键词： barriers     future management     ammonia emissions     nitrogen input     water N pollution    

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Present situation and classification of piezoelectric pump

Fang YE, Shouyin WANG, Wei CHENG, Qixiao XIA, Jianhui ZHANG,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 420-429 doi: 10.1007/s11465-009-0052-7

摘要： According to the present classification method for a piezoelectric pump, this paper reviews the development and present situation of piezoelectric pumps in the latest 30 years and finally puts forward a new classification. A volumetric piezoelectric pump, which belongs to traditional volumetric pumps, can be divided into a piezoelectric pump with or without valves. A new valveless piezoelectric pump nowadays becomes a hot issue in scientific research. It is constructed by using no-moving-part valves, which can induce positive flow resistance and negative flow resistance different, and in which the inlet and outlet are connected all the time. New forms of piezoelectric pumps, different from traditional ones, are only at the stage of conception and principle, and no practical application has been reported.

关键词： piezoelectric pump     development and present situation     new classification method     valveless piezoelectric pump     new forms of piezoelectric pump    

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Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 320-324 doi: 10.1007/s11783-009-0030-7

摘要： The best-fit equations of linear and non-linear forms of the two widely used kinetic models, namely pseudo-first-order and pseudo-second-order equations, were compared in this study. The experimental kinetics of methylene blue adsorption on activated carbon was used for this research. Both the correlation coefficient () and the normalized standard deviation Δ(%) were employed as error analysis methods to determine the best-fitting equations. The results show that the non-linear forms of pseudo-first-order and pseudo-second-order models were more suitable than the linear forms for fitting the experimental data. The experimental kinetics may have been distorted by linearization of the linear kinetic equations, and thus, the non-linear forms of kinetic equations should be primarily used to obtain the adsorption parameters. In addition, the Δ(%) method for error analysis may be better to determine the best-fitting model in this case.

关键词： adsorption     pseudo-first order     pseudo-second order     kinetic model     linear method     non-linear method    

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Recent advances and challenges of nitrogen/nitrate electro catalytic reduction to ammonia synthesis

《能源前沿（英文）》 doi: 10.1007/s11708-023-0908-2

摘要： The Haber-Bosch process is the most widely used synthetic ammonia technology at present. Since its invention, it has provided an important guarantee for global food security. However, the traditional Haber-Bosch ammonia synthesis process consumes a lot of energy and causes serious environmental pollution. Under the serious pressure of energy and environment, a green, clean, and sustainable ammonia synthesis route is urgently needed. Electrochemical synthesis of ammonia is a green and mild new method for preparing ammonia, which can directly convert nitrogen or nitrate into ammonia using electricity driven by solar, wind, or water energy, without greenhouse gas and toxic gas emissions. Herein, the basic mechanism of the nitrogen reduction reaction (NRR) to ammonia and nitrate reduction reaction (NO3− RR) to ammonia were discussed. The representative approaches and major technologies, such as lithium mediated electrolysis and solid oxide electrolysis cell (SOEC) electrolysis for NRR, high activity catalyst and advanced electrochemical device fabrication for NO3 − RR and electrochemical ammonia synthesis were summarized. Based on the above discussion and analysis, the main challenges and development directions for electrochemical ammonia synthesis were further proposed.

关键词： electrochemical ammonia synthesis     nitrogen     nitrate     nitrogen reduction reaction (NRR) to ammonia     nitrate reduction reaction (NO–3 RR)    

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ECOLOGICAL EFFECTS OF NITROGEN DEPOSITION ON URBAN FORESTS: AN OVERVIEW

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 445-456 doi: 10.15302/J-FASE-2021429

摘要：

● Patterns and effects of N deposition on urban forests are reviewed.

关键词： biodiversity     carbon sequestration     nitrogen deposition     nutrient imbalance     soil acidification     urban forest    

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标题 作者 时间 类型 操作

EFFECTS OF SUBSTITUTION OF MINERAL NITROGEN WITH ORGANIC AMENDMENTS ON NITROGEN LOSS FROM SLOPING CROPLAND

期刊论文

Unnormalized and normalized forms of gefura measures in directed and undirected networks

Raf GUNS,Ronald ROUSSEAU

期刊论文

Spatial distribution of phosphorus forms in sediments with different distances to the estuary of the

Shaoyong LU, Xiangcan JIN, Fengchang WU, Jing SI, Jianning GUO,

期刊论文

Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments

Hongguang CHENG,Xiao PU,Yiting CHEN,Fanghua HAO,Liming DONG

期刊论文

SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

期刊论文

SUSTAINABLE NITROGEN MANAGEMENT FOR VEGETABLE PRODUCTION IN CHINA

期刊论文

Micro/nanofluidics-enabled energy conversion and its implemented devices

Yang YANG, Jing LIU

期刊论文

Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

期刊论文

SOIL NITROGEN CYCLING AND ENVIRONMENTAL IMPACTS IN THE SUBTROPICAL HILLY REGION OF CHINA: EVIDENCE FROM

期刊论文

PROGRESS ON IMPROVING AGRICULTURAL NITROGEN USE EFFICIENCY: UK-CHINA VIRTUAL JOINT CENTERS ON NITROGEN

期刊论文

IMPROVING NITROGEN SAFETY IN CHINA: NITROGEN FLOWS, POLLUTION AND CONTROL

期刊论文

Present situation and classification of piezoelectric pump

Fang YE, Shouyin WANG, Wei CHENG, Qixiao XIA, Jianhui ZHANG,

期刊论文

Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

期刊论文

Recent advances and challenges of nitrogen/nitrate electro catalytic reduction to ammonia synthesis

期刊论文

ECOLOGICAL EFFECTS OF NITROGEN DEPOSITION ON URBAN FORESTS: AN OVERVIEW

期刊论文