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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

Six-month clinical outcomes of Firebird 2TM sirolimus-eluting stent implantation in real-world patients with coronary artery diseases

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Chinese Medical Journal 2011年第6期124卷 831-835页

作者： GE jun-bo ZHANG Feng QIAN Ju-ying GE Lei liu xue-bo ZHOU jun Shanghai Institute of Cardiovascular Diseases Zhongshan Hospital Fudan University Shanghai 200032 China

Background The Firebird 2TM sirolimus-eluting stent （Firebird 2 stent） is a second-generation sirolimus-eluting stent which has a cobalt-chromium alloy stent platform, a brand new bracket structure, and two layers of styrene-butylenes-styrene polymer coatings with better biocompatibility. The Firebird 2TM cObalt-Chromium alloy sirolimus-elUting Stent registry （FOCUS registry） aimed to evaluate the safety and efficacy of the Firebird 2 stent in patients with coronary artery disease in daily *** The FOCUS registry is a prospective, non-randomized, international multi-center, single-arm clinical *** March 2009 and February 2010, 5084 patients receiving at least 1 Firebird 2 stent during daily clinical practice at 83 medical centers were *** Of the 5084 patients enrolled in the registry, 5077 and 5058 were respectively available for 30 days and 6 months follow-up. The 30-day rate of major adverse cardiac events （MACE） was 1.20%, including 13 cardiac deaths, 46 non-fatal myocardial infarction （MI）, and 6 target vessel revascularization （TVR）. At 6 months follow-up, the rate of MACE was 1.80%. There were 32 cardiac deaths, 48 non-fatal MI, and 15 TVR. According to the Academic Research Consortium definition, definite/probable stent thrombosis （ST） occurred in 0.43% （22/5058） of patients, including 8 cases of acute ST, 11 subacute ST, and 3 late *** The Firebird 2 stent showed the promising efficacy and safety at 30 days and 6 months in a real-world population of patients with coronary artery diseases.

关键词： sirolimus-eluting stent percutaneous coronary intervention coronary artery disease cobalt-chromium alloy

A three-dimensional transient electromagnetic data inversion method based on a time–frequency transformation

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Applied Geophysics 2020年第3期17卷 361-376页

作者： Yang Yun-Jian Wang Xu-Ben liu xue-jun Mi Xiao-Li Mao Lifeng College of Geophysics Chengdu University of TechnologyChengduSichuan 610059China BGP Inc. Zhuozhou 072750China

Herein,a three-dimensional(3D)inversion method in the frequency domain based on a time–frequency transformation was developed to improve the efficiency of the 3D inversion of transient electromagnetic(TEM)*** Fourier transform related to the electromagnetic response in the frequency and time domains becomes a sine or cosine transform under the excitation of downward-step *** established a transformation matrix based on the digital fi ltering calculation for the sine transform,and then the frequency domain projection of the TEM data was determined from the linear transformation system using the smoothing constrained least squares inversion method,in which only the imaginary part was used to maintain the TEM data transformation equivalence in the bidirectional ***,the time-domain TEM inversion problem was indirectly and effectively solved in the frequency *** the 3D inversion of the transformed frequency-domain data,the limited-memory Broyden–Fletcher–Goldfarb–Shannoquasi–Newton(L-BFGS)method was used and modifi ed with a restart strategy to adjust the regularization parameter when the algorithm tended to a local *** data tests showed that our domain transformation method can stably project the TEM data into the frequency domain with very high accuracy;furthe rmore,the 3D inversion of the transformed frequency-domain data is stable,can be used to recover the real resistivity model with an acceptable effi ciency.

关键词： Transient electromagnetic method TEM digital filtering time-frequency transformation 3D EM forward 3D EM inversion

Research on UWB-based Location Technology Applied for Hazardous Chemicals Stacking Storage

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Research on UWB-based Location Technology Applied for Hazard...

改进的灰色GM(1,1)模型在晚霜冻预报中的应用

第26届中国控制与决策会议

作者： LV Xin liu xue-jun DAI Bo Beijing University of Chemical Technology College of Information Science & Technology Beijing Institute of Petrochemical Technology College of Information Engineering

Currently,domestic dangerous chemicals are always stacked in the warehouse,there is no an effective method for monitoring the five distances in the storage that are subject to the safety standards---pile spacing,wall spacing,zenith distance,column spacing and lamp *** research on timely monitoring and early alarming of dangerous chemicals stacking is *** this paper,the indoor Ubisense location system is established to study the static and dynamic locaiton *** experiments show the UWB positioning technology is truly effective and *** addition,it is really suitable for the stacking safety monitoring of dangerous chemicals storage.

关键词： hazardous chemicals stacking storage UWB locating

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中国农业气象 2014年第3期35卷 305-310页

作者：刘学军山西省阳城县气象局阳城048100

从山西省阳城县1957-2013年春季晚霜冻出现日期中找出最晚出现日期作为0点,求出各晚霜冻日期与0点的相对日期,将灾变点的相对日期确定为灾变阈值。绘制相对日期年际变化曲线和阈值水平线,把二者第二个交点及之后各交点分别到第一个交点... 详细信息

从山西省阳城县1957-2013年春季晚霜冻出现日期中找出最晚出现日期作为0点,求出各晚霜冻日期与0点的相对日期,将灾变点的相对日期确定为灾变阈值。绘制相对日期年际变化曲线和阈值水平线,把二者第二个交点及之后各交点分别到第一个交点的间距作为灰色GM(1,1)模型建模的原始数据序列,从而建立GM(1,1)传统模型,利用优化序列、优化背景值和灰数等维递补方法逐步改进模型,并对各改进型模型进行相对误差、方差比和小误差概率检验,将检验后的最优模型用于预测晚霜冻。结果表明,3种改进方法同时结合后所建模型的预测效果最理想,用来预测晚霜冻具有较高的可信度,根据模型预测,阳城县在2001年最后一次出现晚霜冻后,未来出现晚霜冻的年份为2030年和2044年。研究结果旨在为当地农业生产防御晚霜冻提供可参考的理论依据。

关键词：改进 GM(1,1)模型晚霜冻预报