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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance

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Agricultural Sciences in China 2009年第10期8卷 1246-1255页

作者： YUAN Wei-ling CAO Cou-gui LI cheng-fang ZHAN ming CAI ming-li WANG Jin-ping Crop Physiology and Production Center （CPPC） Huazhong Agricultural University~Key Laboratory of Huazhong Crop PhysiologyEcology and Production Ministry of Agriculture Wuhan 430070 P.R China

Rice-duck （RD） and rice-fish （RF） ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane （CH4） and nitrous oxide （N2O） emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials （GWPs）, we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly （P〈 0.05） lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly （P〈0.05） higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK （5 997.6 and 5 391.5 RMB yuan ha^-1）. Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits.

关键词： methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem,greenhouse effect economic benefit

Preparation and characterization of mesoporous tetragonal sulfated zirconia

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Chinese Chemical Letters 2009年第7期20卷 869-872页

作者： Chun Xia He Bin Yue Ji fang cheng Wei ming Hua Ying Hong Yue He Yong He Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Laboratory of Advanced Materials Fudan University Shanghai 200433 China

Mesoporous tetragonal sulfated zirconia with high surface area and narrow pore-size distribution was prepared using Zr（O-nPr）4 as zirconium precursor, sulfuric acid as sulfur source and triblock copolymer poly（ethylene glycol）-poly（propylene glycol）- poly（ethylene glycol）（P123） as the template. The samples were characterized by X-ray diffraction, N2 sorption, TEM, and NH3- TPD. A phase transformation from monoclinic sulfated zirconia to tetragonal sulfated zirconia is observed. The product shows strong acidity.C2009 Bin Yue. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Sulfated zirconia Mesoporous TEM Phase transformation Acidity

Effects of long-term full straw return on yield and potassium response in wheat-maize rotation

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Journal of Integrative Agriculture 2015年第12期14卷 2467-2476页

作者： BAI You-lu WANG Lei LU Yan-li YANG Li-ping ZHOU Li-ping NI Lu cheng ming-fang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

The effect of long-term straw return on crop yield, soil potassium（K） content, soil organic matter, and crop response to K from both straw and chemical K fertilizer（K_2SO_4） were investigated in a fixed site field experiment for winter wheat-summer maize rotation in 6 years for 12 seasons. The field experiment was located in northern part of North China Plain with a sandy soil in relatively low yield potential. Two factors, straw return and chemical K fertilizer, were studied with two levels in each factor. Field split design was employed, with two straw treatments, full straw return of previous crop（St） and no straw return, in main plots, and two chemical K fertilizer treatments, 0 and 60 kg K2 O ha^（–1）, as sub-plots. The results showed that straw return significantly increased yields of winter wheat and summer maize by 16.5 and 13.2% in average, respectively, and the positive effect of straw return to crop yield showed more effective in lower yield season. Straw return significantly increased K absorption by the crops, with significant increase in straw part. In treatment with straw return, the K content in crop straw increased by 15.9 and 21.8% in wheat and maize, respectively, compared with no straw return treatment. But, straw return had little effect on K content in grain of the crops. Straw return had significant influences on total K uptake by wheat and maize plants, with an increase of 32.7 and 30.9%, respectively. There was a significant correlation between crop yield and K uptake by the plant. To produce 100 kg grain, the wheat and maize plants absorbed 3.26 and 2.24 kg K2 O, respectively. The contents of soil available K and soil organic matter were significantly affected by the straw return with an increase of 6.07 and 23.0%, respectively, compared to no straw return treatment. K_2SO_4 application in rate of 60 kg K2 O ha^（–1） showed no significant effect on wheat and maize yield, K content in crop straw, total K uptake by the crops, soil available K c

关键词： straw return potassium in straw wheat maize potassium response

Comparative experimental study on inhibiting gas explosion using ABC dry powder and diatomite powder

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Journal of Coal Science & Engineering(China) 2012年第2期18卷 138-142页

作者： DENG Jun PU Guang-mei LUO Zhen-min cheng fang-ming School of Energy Engineering Xi'an University of Science and TechnologyXi'an 710054China Key Laboratory of Western Mine Exploitation and Hazard Prevention Ministry of EducationXi'an 710054China

Using a 20 L spherical explosion suppressing test system, the largest gas explosion pressure and maximum pressure rising rate with additives of ultra-fine ABC dry powder and diatomite powder were tested and compared, and the explosion suppression effect of the two kinds of powder was analyzed. Experimental results show that both powders can suppress gas ex- plosion and ABC dry powder is superior to diatomite powder. Adding two powders under the same experimental conditions, when methane concentration is 7.0%, the maximum explosion pressure decreased 39% and 4%, respectively, while the rising rate of the maximum pressure decreased 80% and 53%, respectively. When methane concentration is 9.5%, the maximum ex- plosion pressure decreased 14% and 12%, respectively, the rising rate of maximum pressure decreased 62% and 27%, respec- tively, the maximum explosion pressure decreased 23% and 18%, respectively, while the rising rate of the maximum pressure decreased 77% and 70%, respectively. When methane concentration is 12.0%, the explosion suppression effect of ultra-fine ABC dry powder is not affected by the methane concentration, and the explosion suppression effect of diatomite powder under high methane concentrations is more obvious.

关键词： gas explosion ABC dry powder explosion suppression diatomite

Numerical simulations of magnetic reconnection in the lower solar atmosphere

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Research in Astronomy and Astrophysics 2011年第2期11卷 225-236页

作者： Xiao-Yan Xu 1,2,cheng fang 2,ming-De Ding 2 and Dan-Hui Gao 2 1 Purple Mountain Observatory,Chinese Academy of Science,Nanjing 210008,China 2 Department of Astronomy,Nanjing University,Nanjing 210093,China Purple Mountain Observatory Chinese Academy of Science Nanjing 210008 China Department of Astronomy Nanjing University Nanjing 210093 China

Observations indicate that Ellerman bombs （EBs） and chromospheric microflares both occur in the lower solar atmosphere,and share many common features,such as temperature enhancements,accompanying jet-like mass motions,short life-time,and so *** strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar *** gravity,ionization and radiation considered,we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar *** influence of different parameters,such as intensity of the magnetic field and anomalous resistivity,on the results are *** result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic *** spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with *** is found that the typical features of the two phenomena can be qualitatively reproduced.

关键词： Sun: chromosphere-- Sun: photosphere -- Sun: magnetic reconnection-- Sun: numerical simulation

一氧化碳影响二氧化碳惰化甲烷爆炸的实验研究

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西安科技大学学报 2016年第3期36卷 315-319页

作者：程方明邓军西安科技大学能源学院陕西西安710054 教育部西部矿井开采及灾害防治重点实验室陕西西安710054

为了全面考察火灾产物一氧化碳对矿井瓦斯爆炸危险性的影响,采用标准的可燃气体爆炸极限测试装置,测试研究了CO影响CO_2惰化抑制CH_4爆炸的规律。分别测试分析了含有不同浓度CO时CH_4在空气中的爆炸极限和CO_2惰化条件下的CH_4爆炸极限... 详细信息

为了全面考察火灾产物一氧化碳对矿井瓦斯爆炸危险性的影响,采用标准的可燃气体爆炸极限测试装置,测试研究了CO影响CO_2惰化抑制CH_4爆炸的规律。分别测试分析了含有不同浓度CO时CH_4在空气中的爆炸极限和CO_2惰化条件下的CH_4爆炸极限与临界参数,并绘制出CH_4爆炸三角形分析图,研究了CO对CH_4爆炸三角形位置及大小的影响。结果表明,少量CO气体可使空气中CH_4的爆炸上限和下限均有所下降,爆炸危险度F值增大;CO气体的存在会导致CO_2惰化抑制CH_4爆炸的临界浓度升高,且随CO含量的增大呈线性增加,临界氧浓度随着CO浓度的增大而降低;CO气体会引起CH_4爆炸三角形向左下方移动和延伸,可爆区面积增大,不爆炸区面积缩小,窒息比明显提高,需要添加更多的惰性气体才能使CH_4处于完全惰化状态。

关键词：瓦斯爆炸一氧化碳惰化爆炸三角形

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无电源触发式抑爆装置研究

安全与环境学报 2009年第3期9卷 144-147页

作者：蔡周全程方明西安科技大学能源学院西安710054

为防止煤矿井下瓦斯煤尘爆炸,研制无电源触发式抑爆装置。在地下试验巷道中进行的瓦斯煤尘爆炸抑爆试验表明,无电源触发式抑爆装置能在距爆源45m内扑灭火焰,抑制爆炸。该装置能现场使用、维护方便、成本低,可在较近距离抑制爆炸传播,结... 详细信息

为防止煤矿井下瓦斯煤尘爆炸,研制无电源触发式抑爆装置。在地下试验巷道中进行的瓦斯煤尘爆炸抑爆试验表明,无电源触发式抑爆装置能在距爆源45m内扑灭火焰,抑制爆炸。该装置能现场使用、维护方便、成本低,可在较近距离抑制爆炸传播,结合了被动、自动隔抑爆装置的优点,比现有技术有更好的推广应用前景。

关键词：矿山安全无电源抑爆装置喷洒器抑爆试验

快速响应型P(NIPA-co-SA)水凝胶制备及温敏性能

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功能材料 2014年第B12期45卷 129-135页

作者：杨漪邓军程方明赵大龙唐凯西安科技大学能源学院西安710054 西安市公安消防支队长安中队西安710065 中国人民武装警察部队学院科研部河北廊坊065000

研究具有较高LCST且响应速率快的温敏性水凝胶。以NaCl水溶液为反应介质,采用相分离法合成了多孔水凝胶P(NIPA-co-SA)。利用傅立叶变换红外光谱仪(FT-IR)表征产物结构,并借助扫描电子显微镜、差示扫描量热法(DSC)、浊度法等手段研究了... 详细信息

研究具有较高LCST且响应速率快的温敏性水凝胶。以NaCl水溶液为反应介质,采用相分离法合成了多孔水凝胶P(NIPA-co-SA)。利用傅立叶变换红外光谱仪(FT-IR)表征产物结构,并借助扫描电子显微镜、差示扫描量热法(DSC)、浊度法等手段研究了反应介质浓度对产物微观形貌、相变温度和相变响应速率的影响规律。结果表明,P(NIPA-co-SA)水凝胶具有对温度敏感的响应特性,其低临界溶解温度(LCST)可达到75℃。NaCl水溶液浓度不影响产物的LCST,且随着反应中NaCl水溶液浓度的提高,水凝胶表面逐渐出现不连续的浅而封闭的小孔到互相贯穿的开孔,水凝胶相变响应速率在一定范围内逐渐提高,具有快速响应特性。

关键词： N-异丙基丙烯酰胺多孔水凝胶快速响应温度敏感性

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汉日语方位词的特性与作用分析

西南民族大学学报（人文社会科学版） 2002年第S4期23卷 329-332页

作者：刘旭宝程放明西南交通大学外国学院四川成都610031

在汉语和日语的语言表达中 ,方位词出现频率高、使用范围广 ,其语言功能不容忽视。汉语和日语都各有一套完整的方位词系列 ,而且 ,由于日语的方位词基本都由汉字构成 ,所以从结构上看 ,汉语和日语的方位词系列非常接近。一、方位词的类... 详细信息

在汉语和日语的语言表达中 ,方位词出现频率高、使用范围广 ,其语言功能不容忽视。汉语和日语都各有一套完整的方位词系列 ,而且 ,由于日语的方位词基本都由汉字构成 ,所以从结构上看 ,汉语和日语的方位词系列非常接近。一、方位词的类别与构成 ;二。

关键词：汉日语方位词特性功能