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Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

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Pedosphere 2006年第2期16卷 224-229页

作者： JU Xiao-Tang liu xue-jun ZHANG Fu-Suo P. CHRISTIE Key Laboratory of Plant-Soil Interactions Ministry of Education College of Agricultural Resources and Environmental Sciences China Agricultural University Beijing 100094 （China） Agricultural and Environmental Science Department The Queen＇s University of Belfast Belfast BT9 5PX （UK）

In order to illustrate the change of nitrogen （N） supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil. Soil total N （TN） and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-lnsoluble N, amino acid N and ammonium N in the soil increased significantly （P 〈 0.05） with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased （P 〈 0.05） hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.

关键词： chemical fertilizer long-term fertilization manure North China Plain soil organic nitrogen forms

Moderate drought alleviates the damage to grain quality at high temperatures by improving the starch synthesis of inferior grains in japonica rice

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Journal of Integrative Agriculture 2022年第10期21卷 3094-3101页

作者： TONG Hui DUAN Hua WANG Sheng-jun SU Jing-ping SUN Yue liu Yan-qing TANG Liang liu xue-jun CHEN Wen-fu Rice Research Institute Shenyang Agricultural UniversityShenyang 110866P.R.China Tianjin Key Laboratory of Crop Genetics and Breeding Tianjin Crop Research InstituteTianjin 300384P.R.China

In agricultural production,temperature and moisture are important factors affecting grain yield and *** moderate drought at the grain-filling stage can effectively alleviate the damage caused by high temperature,the specific regulatory mechanism driving the effect of moderate drought at the high temperature on starch synthesis is still *** explore the effects and mechanisms of high temperature and moderate drought on rice starch synthesis at the grainfilling stage,the activities of enzymes and expression levels of the genes involved in starch synthesis under four different treatments involving high temperature and/or water stress(CK,HT,WS,and HT+WS)were investigated in this *** starch synthesis of a japonica inbred rice was measured under the four treatments during the grain *** results show that the effects of high temperature and moderate drought on grain filling mainly occur in the inferior grains of *** the regulation of enzymes involved in starch synthesis and the expression levels of their main genes,the synthesis of rice starch can be ***,the high temperature and moderate drought were antagonistic,and moderate drought can alleviate the damage to grain quality at a high temperature by improving the starch synthesis of inferior grains in japonica *** study provides a basis for stress-resistance cultivation and breeding strategies of rice with high temperature tolerance.

关键词： high temperature moderate drought antagonism starch synthesis japonica rice

Asymmetric synthesis of pedamide using I_2-induced heterocyclization to construct the skeleton

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Chinese Chemical Letters 2009年第7期20卷 775-778页

作者： De Gang liu Ji jun xue Zhi Xiang Xie Li Ping Wei Hua Bing Zhang Ying Li State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 PR China

An alternative approach to synthesize pedamide, a key building block of pederin was described. Iodine-induced asymmetric heterocyclization was used as the key step to construct the skeleton, a tetrahydropyran ring with three chiral centers. Brown＇s asymmetric allylation and Lewis acid-mediated allylation were investigated to introduce chains and chiral alcohols. Sharpless dihydroxylation decorated the side chain. And high optically pure target was obtained by removing the epimers formed in these reactions on column chromatography.C2009 Ji jun xue. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Synthesis Pedamide Pederin

A Granularity-Aware Parallel Aggregation Method for Data Streams

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 133-137页

作者： WANG Yong-li XU Hong-bing XU Li-zhen QIAN Jiang-bo liu xue-jun Department of Computer Science and Engineering Southeast University Nanjing 210096 Jiangsu China

This paper focuses on the parallel aggregation processing of data streams based on the shared-nothing architecture. A novel granularity-aware parallel aggregating model is proposed. It employs parallel sampling and linear regression to describe the characteristics of the data quantity in the query window in order to determine the partition granularity of tuples, and utilizes equal depth histogram to implement partitio ning. This method can avoid data skew and reduce communi cation cost. The experiment results on both synthetic data and actual data prove that the proposed method is efficient, practical and suitable for time-varying data streams processing.

关键词： data streams parallel processing linear regression aggregation data skew

Study on Soil Denitrification in Wheat-Maize Rotation System

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Agricultural Sciences in China 2006年第1期5卷 45-49页

作者： ZOU Guo-yuan ZHANG Fu-suo JU Xiao-tang CHEN Xin-ping liu xue-jun Institute of Plant Nutrition and Natural Resources Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 P.R.China Department of Plant Nutrition China Agricultural University Beijing 100094 P.R.China

Soil denitrification was studied in wheat-maize rotation cropping system on an aquic cambisol. Results showed that the N loss amount by denitrification ranged from 4.7 to 9.7 kg per hectare with different levels of nitrogen application and the key stage for denitification was during summer maize-growth-period, especially within 1-2 weeks after fertilizer nitrogen was applied. Similar trend was found between soil N2O production/emission dynamic and denitrification dynamic in the rotation system, which may indicate that mainly N2O is produced in nitrification process.

关键词： aquic cambisol winter wheat summer maize denitrification N2O

PbrMYB4,a R2R3-MYB protein,regulates pear stone cell lignification through activation of lignin biosynthesis genes

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Horticultural Plant Journal 2025年第1期11卷 105-122页

作者： Dongliang liu Yongsong xue Runze Wang Bobo Song Cheng xue Yanfei Shan Zhaolong xue jun Wu College of Horticulture State Key Laboratory of Crop Genetics&Germplasm Enhancement and UtilizationNanjing Agricultural UniversityNanjingJiangsu 210095China Anhui Provincial Key Laboratoryof Horticultural Crop Quality Biology Schoolof HorticultureAnhui Agricultural UniversityHefeiAnhui 230036 China State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China

Pear(Pyrus bretschneideri)fruit stone cells are primarily composed of lignin and have strongly lignified cell *** presence of stone cells has a negative influence on fruit texture and taste,and thus the reduction of stone cell content in pear fruit is a key goal of breeding ***,research into the key transcription factors and regulatory networks associated with pear fruit stone cell formation have been *** here used a combination of co-expression network and expression quantitative trait locus(eQTL)analyses in 206 pear cultivars with different stone cell contents to identify relevant genes;these analyses uncovered the gene PbrMYB4,a R2R3 MYB transcription factor *** was a strong positive correlation between relative PbrMYB4 expression levels in the fruit flesh and stone cell/lignin *** of PbrMYB4 significantly increased the lignin contents,whereas silencing of PbrMYB4 had the opposite effect,decreasing the contents of ***4 overexpression in pear calli significantly promoted lignin *** Arabidopsis thaliana,PbrMYB4 overexpression resulted in increasing lignin deposition,cell wall thickness of vessels and xylary fiber,and accelerating expression level of lignin biosynthetic ***4 was found to activate 4-Coumarate:Coenzyme A Ligase(Pbr4CL1)by binding to AC-I elements in the promoter regions,as demonstrated with dual-luciferase reporter assays and a yeast one-hybrid *** results demonstrated that PbrMYB4 positively regulated lignin biosynthesis in pear fruit stone cells by activating lignin biosynthesis *** study improves our understanding of the gene regulatory networks associated with stone cell formation in pear fruit,providing guidance for molecular breeding of pear varieties with low stone cell content.

关键词： Pear Stone cell R2R3-MYBs Lignin

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen xue-jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Influence of heat treatment on microstructure of a newβ-solidifyingγ-TiAl alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 239-248页

作者： Li Quan Xiao-bing Li Peng xue jun-jie Hao Kun Qian Bo Chen Jian-zhong Li Kui liu School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Department of Materials Science and Technology Ji Hua LaboratoryFoshan528200GuangdongChina

The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl ***,it is a huge challenge to design an alloy with good hot-deformability as well as the full-lamellar *** low-cost Ti-42.5Al-2Mn-0.4Mo-0.1B-0.1C(at.%)alloy was designed,which undergoes bothβandαsingle-phase region during the *** is found that the full-lamellar structure can be obtained by the solution heat treatment at 1230℃ for 20 min and then aging treatment at 800℃ for 3 ***,a new microstructure,namely,the pearlitic-like microstructure(PM)induced by theα_(2)/γ→βo+γcellular reaction was observed when the aging temperature is increased to above 800℃.The volume fraction of the PM is gradually increased from 0%to 25.5%,65%,and 94%according to elevated aging temperature from 800 to 900,1000,and 1050℃,*** mechanism of the reducedα_(2)/γlamellae and PM formation was discussed regarding the heterogeneous distribution ofβstabilizing elements and the interface energy stored inα_(2)/γlamellae.

关键词： β-γ-TiAl Alloy design Two-step heat treatment Full-lamellar structure Cellular reaction

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU Lin LI xue XIE jun DONG Ming School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Optical Information and Energy Engineering Wuhan Institute of TechnologyWuhan 430205China School of Energy and Environment Shenyang Aerospace UniversityShenyang 110136China

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method(LES-DEM)*** validity of the LES approach was verified by comparison with available direct numerical simulation(DNS)*** adopted the Johnson-Kendall-Roberts(JKR)contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters(d_(p)=2-20μm)in the laminar and transition of shear layer(TrSL)flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise(y-direction).With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： microparticle particle agglomeration discrete element method large eddy simulation