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不同母质发育水稻土N_(2)O消耗潜力及环境影响因素

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中国土壤与肥料 2024年第4期 35-44页

作者：杨曼钟金梅王薇赵丽娅李兆华李昆王玲湖北省区域发展与环境响应重点实验室湖北大学湖北武汉430062 湖北省农村安全饮用水工程技术研究中心湖北武汉430062

土壤是N_(2)O的源和汇,在淹水和厌氧条件下具有消耗N_(2)O的能力。稻田土壤长期处于淹水状态,为N_(2)O的消耗提供了有利的环境,从而减少了N_(2)O排放。目前,有关稻田土壤N_(2)O排放的相关研究已有很多,但关于稻田表层土壤N_(2)O的消耗... 详细信息

土壤是N_(2)O的源和汇,在淹水和厌氧条件下具有消耗N_(2)O的能力。稻田土壤长期处于淹水状态,为N_(2)O的消耗提供了有利的环境,从而减少了N_(2)O排放。目前,有关稻田土壤N_(2)O排放的相关研究已有很多,但关于稻田表层土壤N_(2)O的消耗能力及其与环境因素之间的关系研究较少。研究采集了第四纪红壤母质发育的壤土、湖积物砂土发育的砂质壤土、冲积土发育的粉砂质黏壤土3类土壤的各3个表层(0~5 cm)水稻土,风干后将其回填至具有5 cm深土柱的培养装置内,在土柱底部添加N_(2)O和添加氦气(He,对照)两个处理,于28℃下恒温淹水厌氧培养96 h。培养期间监测各土壤N_(2)O、N_(2)的动态变化,以及培养前后土壤养分的变化,量化N_(2)O消耗量和N2增量,以期揭示稻田表层土壤N_(2)O的消耗能力及其与环境因素之间的关系。结果表明,土壤剖面积累的N_(2)O有95.01%~99.92%被稻田表层土壤吸收,其中被还原为N2的N_(2)O量占总消耗量的64.50%~83.64%,表明淹水厌氧状态下,不同的水稻土均具有很强的N_(2)O吸收和消耗能力。研究还发现,3类土壤N_(2)O的消耗存在一定差异,其中影响砂质壤土N_(2)O消耗的主要环境因子为土壤砂粒含量,且两者之间存在显著的线性相关关系(R^(2)=0.964,P=0.000);土壤黏粒、粉砂粒、pH是粉砂质黏壤土N_(2)O消耗的主要环境影响因素,其中土壤黏粒与其消耗量呈显著线性相关(P<0.05);土壤速效钾和铵态氮增加量是影响壤土N_(2)O消耗的主要环境因子,其消耗量与速效钾之间在0.01水平上显著正相关。这些结果表明,土壤可溶性有机碳、土壤质地、土壤速效钾等是影响稻田土壤N_(2)O消耗的重要环境因子,且不同土壤N_(2)O消耗的环境影响因子存在差异,这将为调节土壤N_(2)O排放提供重要参考。

关键词：表层水稻土 N_(2)O消耗土壤pH 土壤可溶性有机碳土壤质地淹水缺氧

农业主产区生态系统服务供需格局及影响因素分析——以湖北省四湖流域为例

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长江流域资源与环境 2024年第4期33卷 810-821页

作者：贺淑钰王玲陈俊辰戚琦王彬宇李可李兆华李昆湖北大学区域开发与环境响应湖北省重点实验室湖北武汉430062 湖北大学资源环境学院湖北武汉430062

生态系统服务供需匹配状况可以反映区域生态与社会经济发展的协调程度,探究其空间异质性与主导驱动因子对于农业主产区生态与农业的协同发展具有重要意义。以湖北省四湖流域为研究对象,综合多源数据,应用ArcGIS、InVEST模型和地理探测... 详细信息

生态系统服务供需匹配状况可以反映区域生态与社会经济发展的协调程度,探究其空间异质性与主导驱动因子对于农业主产区生态与农业的协同发展具有重要意义。以湖北省四湖流域为研究对象,综合多源数据,应用ArcGIS、InVEST模型和地理探测器等方法,定量分析了四湖流域水源供给、固碳、粮食生产和水质净化等(4)种生态系统服务供需匹配状况、综合供需比及其冷热点区域的驱动因子。结果表明:(1)4种服务供给低值区与需求高值区的空间分布格局相似,主要位于流域西部高城市化区域。(2)除固碳服务外,其他三种服务均能满足流域内部需求,流域综合供需比为0.28,整体处于盈余状态。(3)各项生态系统服务供需比均呈现空间差异性,仅水质净化服务无明显冷点区域,其他服务冷点区域集中在西部高城市化区域,热点区域分布在水域和耕地密集区域。(4)建设用地与耕地分别为影响四湖流域生态系统服务冷点和热点区域供需平衡的主导因子,适当平衡耕地与建设用地的面积,增大湖泊湿地面积是流域实现供需平衡的重要方法。研究结果可为四湖流域和其他类似农业流域的生态系统保护与土地资源可持续利用提供科学支撑。

关键词：生态系统服务供需平衡冷热点分析地理探测器四湖流域

Effect of electric pulse on the crystal structure of solidified copper ingots

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 556-562页

作者： li-hua zhao li Zhan Hao Bai Da-qiang Cang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Shougang Steel Co. Ltd.Sales Company

To obtain advanced quality pure copper, the microstructure of solidified copper was optimized by imposing electric pulse on liquid copper in this study. Experiments were performed to determine the effect of electric pulse voltage, arrangement mode of electrodes, and energy input on the microstructure of solidified copper. The results show that, when the energy input of electric pulse is bigger than 28.95 kJ per ton copper, the percent of fine grains increases noticeably with the increase of energy input; but when the energy input of electric pulse is smaller than 28.95 kJ per ton copper, the percent of fine grains decreases with the increase of energy input. The influence order of above factors on grain refinement is electric pulse voltage 〉 arrangement mode of electrodes 〉 energy input. According to the above experimental results, the optimum process conditions are chosen as the voltage being 400 V and the energy input greater than 28.95 kJ per ton copper. Meanwhile, the best arrangement mode of electrodes should be that, one electrode is immerged in the middle of liquid copper in the crystallizer, and the other is connected to the inner wall of the crystallizer, which is divided into two electrode poles for the symmetrical electric field distribution.

关键词： copper solidification crystal structure electric pulse

Effects of Fe2O3 on the properties of ceramics from steel slag

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 413-419页

作者： Yu li li-hua zhao Ya-kun Wang Da-qiang Cang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China China Electronics Standardization Institute Number 1 An-Dingmeng East Road Beijing 100007 China

Ferric oxide is one of the key factors affecting both the microstructure and the properties of CaO-MgO-SiO2-based ceramics. Research on this effect is significant in the utilization of iron-rich solid wastes in ceramics. Ceramic samples with various Fe2O3 contents（0 wt%, 5 wt%, and 10 wt%） were prepared and the corresponding physical properties and microstructure were studied. The results indicated that Fe2O3 not only played a fluxing role, but also promoted the formation of crystals. Ceramics with 5 wt% of Fe2O3 addition attained the best mechanical properties with a flexural strength of 132.9 MPa. Iron ions were dissolved into diopside, consequently causing phase transformation from diopside and protoenstatite to augite, thereby contributing to the enhancement of its properties. An excess amount of Fe2O3 addition（10 wt% or more） resulted in deteriorated properties due to the generation of an excess volume of liquid and the formation of high-porosity structures within ceramics.

关键词： solid wastes ceramics ferric oxide fluxing role augite phase transformation

Effects of light intensity on activity in four sympatric anuran tadpoles

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Zoological Research 2014年第4期35卷 332-337页

作者： Guo-hua DING Zhi-hua liN li-hua zhao Xiao-li FAN li WEI College of Ecology Lishui University

Though light conditions are known to affect the development and anti-predation strategies of several aquatic species, relatively little is known about how different species react to light, or how light can affect these species during different points in their life-cycle. In this study, we used four sympatric anuran tadpoles （Bufo gargarizans, B. melanostictus, Pelophylax nigromaculatus and Microhyla fissipes） as animal system to examine species-specific activities of the underdoing different light intensity treatments, so as to better understand how they respond to light. We exposed four different species of tadpoles to 1660 and 14 lux light intensity treatments and then measured several parameters including development stage, body length and tail length, and as well as their basic activities. The results of this observation and analysis showed that the activities of tadpoles were significantly greater in B. gargarizans and B. melanostictus than in P. nigromaculatus and M. fissipes; and were also significantly greater during times of high light intensity as compared to during low light intensity. Moreover, the observed relationship between species and light intensity was significant. The activities ofB. gargarizans and B. melanostictus tadpoles were greater in high light, while the activity of P. nigromaculatus tadpoles was greater in low light intensity, while M. fissipes tadpoles showed no differences in either low or high intensity light. Furthermore, the activities orB. gargarizans, B. melanostictus and M. fissipes tadpoles in terms of developmental stage, body size or tail length did not seem to differ with light intensity, but during early larval developmental period of P. nigromaculatus, the activity of tadpoles was negatively correlated with development stage, but irrelevant to either body size or tail length in different light intensities. These results lead us to conclude the observed activities of the four sympatric anuran tadpoles are closely correlated

关键词： Anura Activity Developmental stage light intensity Tadpole

Control of the precipitation of TiN inclusions in gear steels

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 234-239页

作者： Wen-jun Ma Yan-ping Bao li-hua zhao Min Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

In the 20CrMnTi steel production process, the nitrogen content increased by 19 × 10^-6 and 29 × 10^-6, respectively, during ladle furnace（LF） refining and during the casting process from ladle to tundish. The protective casting is the key to decrease the N content. The results of thermodynamic calculations and a growth kinetics investigation show that TiN formation occurs only when the solidification fraction is greater than 0.533 under the controlled conditions used in this study for the manufacture of 20CrMnTi steel; the radius of TiN particles decreases as the Ti and N contents decrease and as the cooling rate increases. Furthermore, the theory of austenite grains controlled by second-phase particles was analyzed. The elemental analysis results showed that the Ti content was controlled at 0.04wt%–0.06wt% and the N content decreased to 0.005wt%, which satisfy the requirements for grain refinement but can also effectively prevent the precipitation of TiN inclusions in 20CrMnTi steel.

关键词： gear steels titanium nitride inclusions precipitation

Purification and characterization of a novel antifungal protein from Bacillus subtilis strain B29

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第4期10卷 264-272页

作者： Jing li Qian YANG li-hua zhao Shu-mei ZHANG Yu-xia WANG Xiao-yu zhao Department of life Science and Engineering Harbin Institute of Technology Harbin 150001 China Institute of Microbiology of Heilongjiang Academy of Sciences Harbin 150010 China Heilongjiang University Press Harbin 150040 China

An antifungal protein was isolated from a culture of Bacillus subtilis strain B29. The isolation procedure comprised ion exchange chromatography on diethylaminoethyl （DEAE）-52 cellulose and gel filtration chromatography on Bio-Gel P-100. The protein was absorbed on DEAE-cellulose and Bio-Gel P-100. The purified antifungal fraction was designated as B29I, with a molecular mass of 42.3 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, pl value 5.69 by isoelectric focusing （IEF）-PAGE, and 97.81% purity by high performance liquid chromatography （HPLC）. B291 exhibited inhibitory activity on mycelial growth in Fusarium oxysporum, Rhizoctonia solani, Fusarium moniliforme, and Sclerotinia sclerotiorum. The 50% inhibitory concentrations （IC50） of its antifungal activity toward Fusarium oxysporum and Rhizoctonia solani were 45 and 112 μmol/L, respectively. B29I also demonstrated an inhibitory effect on conidial spore germination of Fusariurn oxysporum and suppression of germ-tube elongation, and induced distortion, tumescence, and rupture of a portion of the germinated spores.

关键词： Bacillus subtilis Antifungal protein Purification

Optical Properties of Plasmon Resonances with Ag/SiO2/Ag Multi-Layer Composite Nanoparticles

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Chinese Physics Letters 2010年第6期27卷 107-109页

作者： MA Ye-Wan ZHANG li-hua WU zhao-Wang ZHANG Jie School of Physics and Electric Engineering Anqing Teachers College Anqing 246011

Optical properties of plasmon resonance with Ag/SiO2/Ag multi-layer nanoparticles are studied by numerical simulation based on Green＇s function theory. The results show that compared with single-layer Ag nanoparticles, the multi-layer nanoparticles exhibit several distinctive optical properties, e.g. with increasing the numbers of the multi-layer nanoparticles, the scattering efficiency red shiRs, and the intensity of scattering enhances accordingly. It is interesting to find out that slicing an Ag-layer into multi-layers leads to stronger scattering intensity and more ＂hot spots＂ or regions of stronger field enhancement. This property of plasmon resonance of surface Raman scattering has greatly broadened the application scope of Raman spectroscopy. The study of metal surface plasmon resonance characteristics is critical to the further understanding of surface enhanced Raman scattering as well as its applications.

关键词：复合纳米粒子等离子体共振光学性能表面增强拉曼散射银纳米粒子格林函数理论散射强度共振拉曼散射

Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1252-1259页

作者： Min Wang Yan-ping Bao Quan Yang li-hua zhao Lu lin State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing National Engineering Research Center of Flat Rolling Equipment University of Science and Technology Beijing

Low residual-free-oxygen before fmal de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ultra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus （RH） decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace （BOF） endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon （[O]/[C]） in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt% to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the requirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10^6 and 400 × 10^-6 and between 574 × 10^-6 and 775 × 10^-6, respectively, with a temperature of 1695 to 1715℃ and a furnace campaign of 1000 to 5000 heats.

关键词： low carbon steel smelting decarburization cleanness