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Aboveground biomass and nutrient allocation in an age-sequence of Larix olgensis plantations

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Journal of Forestry Research 2011年第1期22卷 71-76页

作者： ZHAO Qiong liu xing-yu ZENG De-hui Institute of Applied Ecology Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 P. R. China.

Biomass and nutrient （N, P, K, Ca, Mg） stock in various aboveground tree components （stemwood, stembark, branches and leaves） were quantified in an age sequence of pure Larix olgensis plantations （20, 35, 53 and 69 years old） in Northeast China. The results show that the aboveground biomass allocation in various tree components was in the order of stemwood （62%-83%）, branches （9%-21%）, stembark （7%-11%） and leaves （1%-6%） for all stands. The proportion of stemwood biomass to total aboveground biomass increased whereas that of other tree components decreased consistently with stand age from 20 to 53 years old, but kept relatively constant with stand age from 53 and 69 years old. The nutrient allocation in various tree components generally followed the same pattern as the biomass allocation （i.e. stemwood 〉 branches 〉 stembark 〉 leaves）. The proportion of nutrient stock in leaves to total aboveground nutrient stock decreased consistently with increasing stand age, while that in stemwood increased with stand age from 20 to 53 years old but then decreased from 53 to 69 years old. The rate of nutrient removal for stands was estimated at different stand ages under different logging schemes, showing that the rate of nutrient removal would be unchanged when the rotation length was shortened to 20 years by the harvest of stem only, but greatly increased by the harvest of total aboveground biomass. The rate of nutrient removal would be a considerable reduction for all elements by debarking, especially for Ca.

关键词： Larix olgensis nutrient allocation stand development nutrient removal

Morphology and Magnetic Properties of Electrodeposited Iron and Nickel Based Alloy Foils

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Journal of Iron and Steel Research International 2004年第6期11卷 45-51页

作者： GUO Zhan-cheng liu Mei-feng SUN Chun-wen liu yu-xing LU Wei-chang Institute of Process Engineering CAS

An alternative to conventional process for the preparation of soft magnetic metal foils of Fe,Fe-Ni,Fe-Co and Fe-Ni-Co by electroforming was *** microstructure and magnetic properties were *** results showed that the crystal size of the iron-based alloy foil is less than 10μm,while that of nickel-based alloy foil is about 2μ***,the electroformed Fe-Ni foil has better magnetic properties than the conventional milled permalloy 1J79 foil.

关键词： electroforming Fe-Ni alloy foil magnetic property microstructure

Simultaneous biodegradation of nitrogen-containing aromatic compounds in a sequencing batch bioreactor

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Journal of Environmental Sciences 2007年第5期19卷 530-535页

作者： liu xing-yu WANG Bao-jun JIANG Cheng-ying ZHAO Ke-xin Harold L. Drake liu Shuang-Jiang State Key Lab of Microbial Resources at Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Ecological Microbiology University of Bayreuth 95445 Bayreuth Germany

Many nitrogen-containing aromatic compounds （NACs）, such as nitrobenzene （NB）, 4-nitrophenol （4-NP）, aniline （AN）, and 2,4-dinitrophenol （2,4-DNP）, are environmentally hazardous, and their removal from contaminated water is one of the main challenges facing wastewater treatment plants. In this study, synthetic wastewater containing NB, 4-NP, 2,4-DNP, and AN at concentrations ranging from 50 to 180 mg/L was fed into a sequencing batch reactor （SBR）. Analyses of the SBR system indicated that it simultaneously removed more than 99% of the NACs at loading rates of 0.36 kg NB/（m^3·d）, 0.3 kg 4-NP/（m^3·d）, 0.25 kg AN/（m^3·d）, and 0.1 kg 2,4-DNP/（m^3·d）. Bacterial groups of Bacteriodetes, Candidate division TM7, α-Proteobacteria, and β-Proteobacteria were dominant in the clone libraries of 16S rRNA genes retrieved from the microbial communities in the SBR system. ＂Cycle tests＂ designed to alter feeding and aeration parameters of the SBR system demonstrated that the resident microbial biome of the SBR system responded rapidly to changing conditions. Consumption of O2 was concomitant with the apparent mineralization of NACs. Aromatic ring-cleaving dioxygenase activities suggested that （1） AN and NB were degraded via catechol 2,3-dioxygenase; （2） 4-NP was degraded via 1,2,4-benzentriol 1,2-dioxygenase; and （3） 2,4-DNP was degraded via an unresolved pathway.

关键词： nitrogen-containing aromatic compounds biodegradation sequencing batch reactor Candidate division TM7

Protective effects of pinacidil hyperpolarizing cardioplegia on myocardial ischemia reperfusion injury by mitochondrial KATP channels

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Chinese Medical Journal 2011年第24期124卷 4205-4210页

作者： yu Tian FU Xiao-yun liu xing-kui yu Zhi-hao Department of Anesthesiology Zunyi Medical College ZunyiGuizhou 563003 China

Background Many studies have indicated that hyperpolarizing cardioplegia is responsible for myocardial preservation and researchers have suggested that the adenosine triphosphate-sensitive potassium channels （KATe） were the end effectors of cardio-protection. But whether mitochondrial KATe plays an important role in hyperpolarizing cardioplegia is not apparent. The present study investigated the effect of hyperpolarizing cardioplegia containing pinacidil （a nonselective KATe opener） on ischemia/repeffusion injury in rat hearts, especially the role of mitochondrial KATe in pinacidil hyperpolarizing cardioplegia. Methods Sprague-Dawley rat hearts were Langendorff-perfused for 20 minutes with Krebs-Henseleit buffer at 37℃ before equilibration. Cardiac arrest was then induced in different treatments： there was no arrest and ischemia in the normal group, the control group were arrested by clamping the aorta, depolarizing caidioplegia （St. Thomas solution containing 16 mmol/L KCI） and hyperpolarizing cardioplegia groups used St. Thomas solution containing 0.05 mmol/L pinacidil and 5 mmol/L KCI to induce cardiac arrest in group hyperkalemic and group pinacidil, in group hyperkalemic ＋ 5-hydroxydecanote （5HD） and Pinacidil ＋ 5HD, 5HD （0.1 retool/L） was added to the above two solutions to block mitochondria KATe channels. Global ischemia was then administrated for 40 minutes at 37℃, followed by 30 minutes of reperfusion. At the end of equilibration and reperfusion, hemodynamics, ultrastructure, and mitochondrial function were measured. Results In the control group, ischemia/reperfusion decreased the left ventricular developed pressure, heart rate, coronary flow, mitochondrial membrane potential, impaired mitochondrial respiratory function, increased reactive oxygen species and left ventricular end diastolic pressure. Damage to myocardial ultrastructure was also evident. Both depolarized arrest and especially hyperpolarized cardioplegia significantly reduced these lesions

关键词： cardioplegic solutions heart arrest pinacidil ischemia/reperfusion injury myocardial mitochondrial ultrastructure potassium channel blockers

新型荧光双重敏感响应性壳聚糖衍生物的合成及其发光性能研究

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高等学校化学学报 2006年第6期27卷 1145-1148页

作者：关晓琳刘兴妤苏致兴兰州大学化学与化工学院兰州730000

为了开发新型多功能天然高分子荧光材料，合成出一种新型含有环氧丙氧基荧光素（EPF）基团的水溶性壳聚糖衍生物GCS-EPF，并用IR，^1H NMR，UV光谱和荧光光谱等手段进行结构和发光性能的研究．结果表明，修饰后水溶性壳聚糖（GCS）的水... 详细信息

为了开发新型多功能天然高分子荧光材料，合成出一种新型含有环氧丙氧基荧光素（EPF）基团的水溶性壳聚糖衍生物GCS-EPF，并用IR，^1H NMR，UV光谱和荧光光谱等手段进行结构和发光性能的研究．结果表明，修饰后水溶性壳聚糖（GCS）的水溶液、固体粉末和薄膜在520nm附近具有较强的荧光发射，其荧光强度不仅在0～60℃时对温度有较快敏感响应，同时在pH=0～13．5时对pH也有较快敏感响应，具有双重敏感响应，因此可将其作为温度荧光探针和pH荧光探针的高分子材料．

关键词：环氧丙氧基荧光素(EPF) 水溶性壳聚糖(GCS) 荧光温度荧光敏感响应 pH荧光敏感响应

聚合物对Eu(TTA)_3·2NMP发光性能的影响

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高等学校化学学报 2005年第4期26卷 769-772页

作者：刘兴妤关晓琳苏致兴兰州大学化学化工学院兰州730000

研究了聚乙烯吡咯烷酮(PVP)、聚乙烯醇(PVA)、聚甲基丙烯酸甲酯(PMMA)三种共混膜材料之间对铕/α-噻吩甲酰三氟丙酮/N-甲基吡咯烷酮[Eu(TTA)3·2NMP]三元配合物发光性能的差异.实验发现,无论是溶液状态,还是共混膜材料,三元配合物/聚合... 详细信息

研究了聚乙烯吡咯烷酮(PVP)、聚乙烯醇(PVA)、聚甲基丙烯酸甲酯(PMMA)三种共混膜材料之间对铕/α-噻吩甲酰三氟丙酮/N-甲基吡咯烷酮[Eu(TTA)3·2NMP]三元配合物发光性能的差异.实验发现,无论是溶液状态,还是共混膜材料,三元配合物/聚合物的荧光强度均大于三元配合物的荧光强度,为稀土荧光物质的成膜与加工提供了重要的实验依据.

关键词： Eu^3+ α-噻吩甲酰三氟丙酮(TTA) 聚乙烯吡咯烷酮(PVP) 聚乙烯醇(PvA) 聚甲基丙烯酸甲酯 (PMMA) 发光性能

Effect of CO_2 and N_2 on microbial community changes during column bioleaching of low-grade high pyrite-bearing chalcocite ore

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Journal of Central South University 2015年第12期22卷 4528-4535页

作者：陈勃伟武彪刘兴宇温建康 National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals

Simulated heap bioleaching of low-grade high pyrite-bearing chalcocite ore was conducted at 40 °C with aeration of CO_2 and N_*** samples were collected at day 43,64,85,106 and subjected to microbial community analysis by 16S rRNA gene clone *** analyses of 16S rDNA fragments revealed that the retrieved sequences are mainly related to genus Acidithiobacillus,Leptospirillum and *** of CO_2 and N_2 significantly impacted the microbial community *** CO_2 was aerated,the proportion of genus Acidithiobacillus considerably increased,whereas the proportion of genus Leptospirillum and genus Sulfobacillus ***,with the aeration of N_2,the proportion of genus Acidithiobacillus and Leptospirillum increased,but genus Sulfobacillus *** there was no aeration,the microbial community was similar to the inocula with the proportion of genus Leptospirillum *** results indicated that the limitation of oxygen could change the bioleaching microbial community and the aeration of CO_2 and N_2 was favourable for the growth of sulfur-oxidizer(***) and iron-oxidizer(***) respectively,which could be used for the regulation of microorganisms' role in mineral bioleaching.

关键词： bioleaching CO2 N2 chalcocite pyrite microbial community

Modeling and Simulation of Lazy Eight Aircraft Maneuver

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Modeling and Simulation of Lazy Eight Aircraft Maneuver

Novel Algorithm to Suppress Random Pulse Interference in Spikes

2012年计算机应用与系统建模国际会议

作者： Pan Wenjun liu xing-yu Wang Lixin School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics General Configuration and Aerodynamics Department of Shanghai Aircraft Design and Research Institute

The Lazy Eight aircraft maneuver is researched through numerical simulation. First, a six DOF aircraft flight dynamics model is developed. To control the aircraft performing the maneuver, a basic flight control law is designed, employing classical PID controllers in both pitch and roll loop. Commands for maneuver simulation are derived from the descriptions of Lazy Eight maneuver flight procedure. By proper settings of the commands and PID controllers’ gain values, Lazy Eight maneuver simulation is conducted exactly according to the maneuver descriptions. The model established in paper also provides researchers and a method to simulate other aircraft maneuvers.

关键词： Flight dynamics Flight simulation Control law PID controller Lazy Eight

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Chinese Journal of Biomedical Engineering(English Edition) 2019年第4期28卷 155-161页

作者： liu xing-yu WANG Yong-yi WAN Hong SHANG Zhi-gang School of Electrical Engineering Zhengzhou UniversityZhengzhou 450052China School of Information Science and Engineering Central South UniversityChangsha 410012China

Spikes detection and sorting play an important role in study of neural information *** were generally obtained by threshold detection after filtered in traditional detection,which failed to suppress the random pulse interference(RPI),In this paper,a novel algorithm was provided to suppress RPI using integrated *** raw neural signals from the primary visual cortex in rats were detected with microelectrode *** the feature differences between spikes and RPls were compared,the features which include waveform and non-waveform features were extracted respectively,and then the integrated feature was established based on Fisher's discrimi nant ratio to separate between spikes and *** test results of simulation and experiment show that the separability capability of the integrated feature is nearly two times greater than the individual feature,the average correct recognition rate of spikes and RPls is over 93%,and the detection rate of spike is effectively improved.

关键词： spike random pulse interference integrated feature