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Agricultural Sciences in China 2009年第1期8卷 68-75页

作者： QIAN Guo-liang HU Bai-shi JIANG Ying-hua liu feng-quan Department of Plant Pathology College of Plant Protection Nanjing Agricultural University~Key Laboratory of Monitoring and Managementof Crop Diseases and Pest Insects Ministry of Agriculture Nanjing 210095 P.R.China

Strain OH11, a Gram-negative, nonspore forming, rod-shaped bacterium with powerful antagonistic activity, was isolated from rhizosphere of green pepper in Jiangsu Academy of Agricultural Sciences of China and characterized to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain OH11 belongs to the Gammaproteobacteria and had the highest degree of sequence similarity to Lysobacter enzymogenes strain C3 （AY074793）（99%）, Lysobacter enzymogenes strain N4-7 （U89965）（99%）, Lysobacter antibioticus strain （AB019582）（97%）, and Lysobacter gummosus strain （AB16136）（97%）. Chemotaxonomic data revealed that strain OHI 1 possesses a quinine system with Q-8 as the predominant compound and C15：0 iso, C17：1 iso ω9c as the predominant iso-branched fatty acids, all of which corroborated the assignment of strain OH11 to the genus Lysobacter. Results of DNA-DNA hybridization and physiological and biochemical tests clearly showed that strain OH11 was classified as Lysobacter enzymogenes. Strain OH11 could produce protease, chitinase, and β-1,3-glucanase. It showed strong in vitro antifungal activity against Rhizoctonia solani, Sclerotinia scletotiorum, and several other phytopathogenic fungi. This is the first report of identification and characterization of Lysobacter enzymogenes as a biological control agent of plant diseases in China.

关键词： Lysobacter enzymogenes identification characterization biological control

Synthesis of O-glycosylα-aryl nitrones

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Chinese Chemical Letters 2010年第9期21卷 1075-1078页

作者： Ying Fu huai Yuan Zhang Yan hua liu Xue feng Li Dan feng huang Yu Lai Hu Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of Education Key Laboratory of Polymer Material of Gansu Province College of Chemistry & Chemical Engineering Northwest Normal University Lanzhou 730070 China

α-Aryl nitrone are one of the most useful kinds of nitrones and have been extensively explored in recent ***,the sugar moieties have not been introduced into these molecules *** presented here an efficient synthesis ofα-aryl nitrone Oglycosides via condensation of N-substituted hydroxylamine and aryl aldehydes glycosides in benzene.

关键词： Nitrones Glycosides Aryl aldehyde Hydroxylamine Synthesis

Productive Performance of Double-Muscled Piemontese Culled Cows in Finishing Period

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Agricultural Sciences in China 2010年第5期9卷 721-728页

作者： GUO Kai-jun liu feng-hua LU Lin Biagini Davide Lazzaroni Carla Zoccarato Ivo College of Animal Science and Technology Beijing University of Agriculture Beijing 102206 P.R.China CAU-BUA TCVM Teaching ＆ Research Team Beijing 102206 P.R.China Dipartimento di Scienze Zootecniche Universita di Torino Turin 10095 Italy

The aims of the study were to evaluate productive performances and environmental impact of double-muscled Piemontese culled cows. In two trials, 39 Piemontese culled cows aged from 46 to 176 mon were fattened using diets commonly applied in farm conditions. The animals were weighed at the beginning and end of the trials. Concentrate and hay intake were recorded daily. After slaughtering, meat, fat and bone yields were recorded and dressing percentage was calculated. The backward linear regression model was employed for statistical analysis. Results showed average body weight （ABW） of cows as （556.97± 55.99） kg and relatively low dry matter intake （DMI） [（9.17± 0.35） kg d^-1] during the fattening period. The ratio between DMI and ABW, i.e., ratio between intake and weight （RIW）, （1.66±0.18）% was negatively influenced by initial body weight （IBW） and duration of finishing period （D）, but age had no effect on RIW. Average daily gain （ADG） was relatively low [（0.55 ±0.21） kg d^-1, and was negatively correlated with IBW and D, which implied that lower IBW and shorter D could have higher ADG and vice versa. The dressing percentage （DP） was （59.80± 1.83）% and the carcass red meat yield （MY） was （75.17±3.10）%. Nevertheless, N efficiency was very low [（4.35 ± 1.76）%], which must be considered in relation to environmental protection so both animal requirements and a well balanced diet need more attention. In conclusion when Piemontese cows will be culled and fattened, IBW and D should be considered carefully in order to get a reasonable ADG and N efficiency to guarantee productive benefits and environmental protection at the same time.

关键词： dry matter intake growth and dressing performance nitrogen efficiency Piemontese culled cows

Potential Distribution of Alien Invasive Species and Risk Assessment:a Case Study of Erwinia amylovora in China

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Agricultural Sciences in China 2007年第6期6卷 688-695页

作者： CHEN Chen CHEN Juan HU Bai-shi IIANG Ying-hua liu feng-quan Key Laboratory of Monitoring and Management of Plant Diseases and Insects Ministry of Agriculture Nanjing Agricultural UniversityNanjing 210095 P.R.China

Alien invasive species represent a severe risk to biodiversity and economy, as in the case of fire blight （Erwinia amylovora）, a bacterial disease that originated in North America, which may be released into new locations by means of fruit trade. On the basis of the knowledge of Erwinia amylovora＇s biophysical characteristics and environmental data, the geographic information system （GIS） has been applied to determine areas where Erwinia amylovora can potentially invade China. Temperature and precipitation, during the blossoming period, are considered to be two critical factors affecting the Erwinia amylovora＇s suitable climatic zones. This spatial modeling approach was validated from a case study in Europe, where the occurrence of Erwinia amylovora has been proven. The model prediction agreed with the occurrence of the bacteria recorded in Europe, and the same procedure has been applied to produce a potential establishment area in China＇s two preferential apple cultivation regions, Bohai Bay region and huangtu Altiplano region. It has been found that areas belonging to the high-risk category are more or less the main apple producing areas, accounting for their great economic importance in China. This methodology provides an initial baseline for assessment, prevention, and management of alien species that may become invasive under certain environmental conditions. In addition, this modeling approach provides a tool for policy makers to use, in making decisions on management practices where alien species are involved.

关键词： biological invasions Erwinia amylovora GIS potential distribution risk assessment

Effect of electroacupuncture at Sibai on the gastric myoelectric acitivities of denervated rats

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World Journal of Gastroenterology 2006年第36期12卷 5897-5901页

作者： Xiao-Rong Chang Jie Yan Yan-Ling Zhao Jiang-Shang Li Jian-hua liu Jun-feng He College of Acupuncture and Massage Hunan University of Traditional Chinese Medicine Changsha 410007 Hunan Province China

AIM： To explore the mechanism of the exciting effects of electro-acupuncture （EA） at Sibai on the gastric myoelectric activities. METHODS： A total of 32 rats were randomly divided into four groups. Through intraperitoneal injection with atropine （the anti-cholinergic agent by blockade of muscarinic receptors）, hexarnethonium （automatic nerve ganglion-blocking agent） and reserpine （anti-adrenergic agent by depleting the adrenergic nerve terminal of its norepinephrine store）, effects of EA at Sibai on the gastric myoelectric activities of the denervated rats were observed. RESULTS： After intraperitoneal injection of atropine and hexamethonium, the average amplitude and ratio of period to time in the phase of high activity of gastric myoelectric slow wave, and the average numbers of the peaks of gastric myoelectric fast wave were significantly decreased （P 〈 0.01, P 〈 0.05, P 〈 0.01）, while after intraperitoneal injection of reserpine, the aforementioned three parameters were increased （P 〈 0.01, P 〈 0.05, P 〈 0.01）. EA at Sibai point partially relieved the inhibitory effect of atropine and hexamethonium on the gastric myoelectric activities in the rats （P 〈 0.05 or P 〉 0.05）. CONCLUSION： Cholinergic and adrenergic nervous systems and autonomic nerve ganglion participate in the peripheral passage of the controlling effects of EA at Foot Yangming Channel on gastrointestinal tract.

关键词： Electro-acupuncture Rats Sibai Nerve block Gastric myoelectric activities

Suppression of Multiples by Improved Expanding Multi-Channel Match Minus Method

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石油地球物理勘探 2009年第3期44卷 52-58页

作者： liu hua-feng Li Qing-Chun Wang Li-Ming Key Lab of Geophysical Exploration of CNPC China University of Petroleum (Beijing) Beijing 102249 China Key Lab of Western Geological Resources and Engineering of Education Ministry Chang'an University Xi'an 710054 China

本文采用基于时差方程的多次波预测方法预测多次波模型记录,结合单道匹配、常规多道匹配、伪多道匹配和扩展多道匹配四种相减方法的优缺点,给出了改进的多道匹配相减方法和改进的扩展多道匹配相减方法的计算步骤,并尝试在匹配相减方法... 详细信息

本文采用基于时差方程的多次波预测方法预测多次波模型记录,结合单道匹配、常规多道匹配、伪多道匹配和扩展多道匹配四种相减方法的优缺点,给出了改进的多道匹配相减方法和改进的扩展多道匹配相减方法的计算步骤,并尝试在匹配相减方法中评估迭代思想的作用.通过理论模型和实测资料的测试,得出了以下主要结论:①在已知水层深度这一先验信息的前提下,利用时差方程方法预测多次波模型记录,计算速度快,精度基本满足要求,是一种预测海底多次波的有效方法;②改进的扩展多道匹配相减方法适应能力较强,具有较好的信号保真度,在模型测试和实际数据应用中,均取得了较为满意的效果,并可与其他预测方法搭配使用;③滤波因子长度、时窗大小和相邻匹配道数这三个主要控制参数,对匹配相减的效果有影响,在应用匹配相减方法时,需要针对数据本身的特点,选择合适的匹配参数.经过对比迭代匹配相减的结果发现,迭代运算对于提高匹配精度的作用不大.

关键词：相匹配多通道预测模型镇压乘数计算速度深度信息测试数据

利用作用深度信息提高正电子断层成像仪分辨率一致性

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物理学报 2006年第10期55卷 5186-5190页

作者：刘华锋浙江大学现代光学仪器国家重点实验室杭州310027

获取作用深度信息是设计小动物正电子断层成像仪的关键技术之一.我们利用新设计的含有作用深度信息的探测器,从模拟与实验两个方面观测了作用深度信息对于分辨率一致性的影响.结果表明:在γ射线垂直入射时,深度编码探测器和一般的无深... 详细信息

获取作用深度信息是设计小动物正电子断层成像仪的关键技术之一.我们利用新设计的含有作用深度信息的探测器,从模拟与实验两个方面观测了作用深度信息对于分辨率一致性的影响.结果表明:在γ射线垂直入射时,深度编码探测器和一般的无深度检出机能的探测器,均获得了高分辨率,而γ射线斜入射时,深度编码探测器与一般的探测器相比能提供更好的空间分辨率.

关键词：作用深度空间分辨率正电子断层成像仪

GPU-based dynamic quad stream for forest rendering

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Science China(Information Sciences) 2010年第8期53卷 1539-1545页

作者： liu feng, hua Wei & BAO HuJun State Key Lab of Computer Aided Design and Computer Graphics, Zhejiang University, Hangzhou 310058, China State Key Lab of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou China

Rendering large-scale forest scenes in real-time is a challenging problem, since the geometric complexity is far beyond the capabilities of current graphics hardware. In this paper, we propose a novel approach that adopts a dynamic quad stream residing on GPU buffers for view-dependent forest rendering. The incremental quad stream updating process is well-suited to the massively parallel architecture of the GPU pipeline, and it requires no continuous data exchange between CPU and GPU. The implementation of the algorithm is quite straightforward. Despite its simplicity, the algorithm achieves good performance with low memory, storage, and CPU costs.

关键词： real-time rendering large-scale forest quad stream geometry shader

Multiple subtraction method based on a non-causal matching filter

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Applied Geophysics 2011年第1期8卷 27-35,94,95页

作者： liu hua-feng Chen Xiao-Hong Song Jia-Wen liu Guo-Chang CNPC Key Lab of Geophysical Exploration China University of Petroleum （Beijing） Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum （Beijing） Beijing 102249 China

The filter operator used in normal multichannel matching filter is physically realizable. This filter operator only delays seismic data in the filtering process. A non- causal multichannel matching filter based on a least squares criterion is proposed to resolve the problem in which predicted multiple model data is later than real data. The differences between causal and non-causal multichannel matching filters are compared using a synthetic shot gather, which demonstrates the validity of the non-causal matching filter. In addition, a variable length sliding window which changes with offset and layer velocity is proposed to solve the count of events increasing with increasing offset in a fixed length sliding window. This variable length sliding window is also introduced into the modified and expanded multichannel matching filter. This method is applied to the Pluto1.5 synthetic data set. The benefits of the non-causal filter operator and variable length sliding window are demonstrated by the good multiple attenuation result.

关键词： multiple matching subtraction non-causal convolution operator variable length window

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高速列车气动性能低温风洞试验

交通运输工程学报 2018年第6期18卷 93-100页

作者：刘凤华中车长春轨道客车股份有限公司吉林长春130062

采用低温风洞试验对比了中国高速列车HST、法国高速列车TGV和德国高速列车ICE3的气动性能;基于EN 14067和TSI标准在铝质材料模型上测试了不同侧偏角下列车阻力、升力和倾覆力矩;利用粒子图像测速技术测量了列车周围流场,得到了高速列车... 详细信息

采用低温风洞试验对比了中国高速列车HST、法国高速列车TGV和德国高速列车ICE3的气动性能;基于EN 14067和TSI标准在铝质材料模型上测试了不同侧偏角下列车阻力、升力和倾覆力矩;利用粒子图像测速技术测量了列车周围流场,得到了高速列车与空气的相互作用机理和气动现象;采用计算流体力学方法模拟了高速列车实际运行情况,并与低温风洞试验流场测试结果进行了对比。研究结果表明:0°～10°侧偏角下列车阻力系数绝对值从大到小依次为HST、ICE3、TGV,侧偏角为0°时,3种列车的阻力系数分别为0.223、0.166、0.140;0°～5°侧偏角下列车升力系数绝对值从大到小依次为TGV、ICE3、HST,且数值均接近0,其中ICE3、HST为正升力,列车受压向轨面力,TGV为负升力,列车受上浮力;0°～5°侧偏角下列车倾覆力矩系数绝对值从大到小依次为TGV、HST、ICE3,侧偏角为0°时,3种列车倾覆力矩系数分别为0.021、0.019、0.011;HST高速列车由于头部双层造型设计,在头部曲面过渡处出现流动分离,增大了列车摩擦阻力和压差阻力,导致列车阻力系数比TGV和ICE3偏大一些,但阻力系数在高速列车头型设计技术要求限值0.25之内,且升力和倾覆力矩性能较好,列车具有良好的稳定性,满足高速列车头型气动设计的工程需求。

关键词：车辆工程高速列车低温风洞试验气动性能雷诺数边界层