巢湖周边地区表层土壤总氮有机质空间分布特征

采用网格分区法在巢湖周边地区设置了60个采样单元,采取表层土样分析了总氮(TN)、有机质(OM)的空间分布特征。结果表明:(1)表层土壤w(TN)平均值为1 027 mg/kg,变化范围253 mg/kg~2 273 mg/kg,变异系数为46.3%;w(OM)平均值为1.95%,变化范围0.291%~5.48%,变异系数为49.3%。(2)表层土壤w(TN)、w(OM)高浓度地区主要集中在东部的柘皋河、兆河区域,低浓度地区主要集中在西部的派河、南淝河—店埠河区域。(3)巢湖周边地区土壤总氮、有机质空间分布与区域内入湖河流、巢湖水质、巢湖沉积物污染空间分布不一致。     

基于数据分析的打印设备能效评估

为了更有效地执行我国能效等级评价标准和降低办公能耗,着重讨论了打印设备的能源效率评价。通过收集的数据来分析打印机能效限定值及相应的能效等级标准的测试方法测试过程中的关键点。通过引入计算模型和介绍测量典型能耗分析法(TEC),操作模式功率法(OM)的步骤和检测方法。对检测需要注意的项目以及有效降低电力能源消耗提出对应的方案和建议。     

太湖北部湖区春、冬季节天然有机质的荧光特征及环境意义

天然有机质(OM)广泛存在于各类水体,含有丰富的碳、氮、磷等生源要素,其形成、转化、归宿及其相伴随的营养盐再生过程是水生态系统营养盐生物地球化学循环的重要环节,在湖泊蓝藻水华暴发过程中势必也扮演着非常重要的营养盐供给者的角色.本研究于2015年2月和5月分别在太湖北部湖区采集了17个样品,利用POM-DOM PARAFAC三维荧光模型解析春、冬季节颗粒态有机质(POM)和溶解态有机质(DOM)的荧光特征及来源,并探讨POM和DOM各荧光组分之间及其与叶绿素a(Chla)的关系.结果表明,春、冬季节太湖北部湖区POM和DOM的荧光峰、荧光中心位置和荧光强度均存在明显的差别;POM有着比DOM更复杂的组分构成.综合POM和DOM的荧光强度和荧光指数可知,春、冬季节太湖北部湖区POM和DOM均以自生源为主,河口区受陆源贡献较大.POM(C1p~C5p)和DOM(C1d~C5d)有5种荧光组分,分别是类色氨酸(C1和C2)、类腐殖质(C3和C4)及类酪氨酸(C5).POM和DOM的荧光组分特征存在明显的差别;春、冬季节POM均以类腐殖质荧光C3为主,荧光组分高值区分别集中在梅梁湾区域和湖心区;而DOM均以类蛋白组分C2、C1和C5为主,荧光组分高值区均分布在竺山湾区域.相关分析结果显示,春季C1d与C2d(P0.01)、C3d与C4d(P0.01)、C1p与C4p(P0.05)、C2p与C5p(P0.01)均具有较强的相关性.值得注意的是,C3d(P0.01)、C4d(P0.05)与C3p均具有较好的相关关系,表明POM与DOM在组分、来源上具有某种联系.与春季类似,冬季荧光组分C1d与C2d、C3d与C4d、C1p与C2p、C1d与C2p亦具有极好的相关性(P0.01).春季C5d与Chla之间存在正相关关系(P0.01),而C2d(P0.05)、C3p(P0.01)与Chla之间具有负相关关系;冬季C4d与Chla之间也存在负相关关系(P0.05).     

Fate and transport of the β-adrenergic agonist ractopamine hydrochloride in soil–water systems

The feed additive ractopamine hydrochloride was fortified at four concentrations into batch vials containing soils that differed in both biological activity and organic matter(OM).Sampling of the liquid layer for 14 days demonstrated that ractopamine rapidly dissipated from the liquid layer. Less than 20% of the fortified dose remained in the liquid layer after 4 hr,and recoveries of dosed ractopamine ranged from 8 to 18% in the liquid layer at 336 hr. Sorption to soil was the major fate for ractopamine in soil:water systems, i.e., 42%–51% of the dose at14 days. The major portion of the sorbed fraction was comprised of non-extractables; a smaller fraction of the sorbed dose was extracted into water and acetone, portions which would be potentially mobile in the environment. Partitioning coefficients for all soils suggested strong sorption of ractopamine to soil which is governed by hydrophobic interactions and cation exchange complexes within the soil OM. Ractopamine degradation was observed, but to mostly non-polar compounds which had a higher potential than ractopamine to sorb to soil. The formation of volatiles was also suggested. Therefore, despite rapid and extensive soil sorption,these studies indicated a portion of ractopamine, present in manures used to fertilize soils,may be mobile in the environment via water-borne events.     

不同肥料种类对稻田红壤碳氮淋失的影响

土壤中碳、氮淋失降低土壤肥力,污染水体环境.为探究不同施肥种类对稻田红壤碳氮淋失影响,本试验依托中国科学院千烟洲生态站(114°53’E,26°48’N)1998年建立的红壤稻田长期定位控制试验,选用负压法采集土壤溶液,研究秸秆还田(ST)、有机肥(OM)、化肥(NPK)对土壤碳、氮淋失状况及时间动态的影响.结果表明:1稻田土壤中氮素淋失以铵态氮(NH+4-N)为主,施用NPK使土壤中NH+4-N(1.2 mg·L-1±0.1 mg·L-1)淋失最严重,施用OM使土壤中可溶解性有机碳(DOC)(27.3 mg·L-1±1.6 mg·L-1)淋失最严重,且土壤中DOC和NH+4-N均在水稻营养生长期淋失最严重(P<0.05);2施用OM与NPK可以增加稻田红壤中NH+4-N、DOC、总有机碳(SOC)和总氮(TN)含量,且施用NPK增加TN效果最显著,施用OM增加SOC最显著;3土壤渗漏液中DOC含量与稻田红壤中SOC含量呈显著正相关(P<0.01),土壤渗漏液中NH+4-N含量与稻田红壤中TN含量呈显著正相关(P<0.01).     

Reduced activity of alkaline phosphatase due to host–guest interactions with humic superstructures

Nuclear Magnetic Resonance (NMR) spectroscopy was applied to directly study the interactions between the alkaline phosphatase enzyme (AP) and two different humic acids from a volcanic soil (HA-V) and a Lignite deposit (HA-L). Addition of humic matter to enzyme solutions caused signals broadening in ¹H-NMR spectra, and progressive decrease and increase of enzyme relaxation (T₁ and T₂) and correlation (τ_C) times, respectively. Spectroscopic changes were explained with formation of ever larger weakly-bound humic–enzyme complexes, whose translational and rotational motion was increasingly restricted. NMR diffusion experiments also showed that the AP diffusive properties were progressively reduced with formation of large humic–enzyme complexes. The more hydrophobic HA-L affected spectral changes more than the more hydrophilic HA-V. ¹H-NMR spectra also showed the effect of progressively greater humic–enzyme complexes on the hydrolysis of an enzyme substrate, the 4-nitrophenyl phosphate disodium salt hexahydrate (p-NPP). While AP catalysis concomitantly decreased NMR signals of p-NPP and increased those of nitrophenol, addition of humic matter progressively and significantly slowed down the rate of change for these signals. In agreement with the observed spectral changes, the AP catalytic activity was more largely inhibited by HA-L than by HA-V. Contrary to previous studies, in which humic–enzyme interactions were only indirectly assumed from changes in spectrophotometric behavior of enzyme substrates, the direct measurements of AP behavior by NMR spectroscopy indicated that humic materials formed weakly-bound host–guest complexes with alkaline phosphatase, and the enzyme catalytic activity was thereby significantly inhibited. These results suggest that the role of extracellular enzymes in soils may be considerably reduced when they come in contact with organic matter dissolved in the soil solution.     

水体沉积物中有机质结构特征与毒害有机物的吸附模式研究

以珠江广州河段沉积物为研究对象,利用红外、紫外、荧光、X射线衍射等手段研究了沉积物中有机质的结构,与其他地区相比发现其芳化度和不饱和度较高,含N量也较高.以萘为吸附质,在碱处理前后的沉积物样品做吸附实验,结果发现沉积物样品接近线性吸附,而碱处理过后却呈现明显的非线性吸附,吸附机理的差异显示与其结构有密切的关系.     

湿法烟气脱硫中烟囱腐蚀及其防腐材料研究现状

介绍了湿法烟气脱硫(WFGD)机理及烟气脱硫处理过程,分析了WFGD处理烟气后引起烟囱严重腐蚀的相关问题.同时,系统地介绍了目前解决烟囱腐蚀的相关防腐材料,并叙述了相关重防腐处理工艺.     

Comprehensive quality assessment of municipal organic waste composts produced by different preparation methods

In the first part of this work, the effect of municipal organic waste (MOW) composts on plant growth was evaluated in a greenhouse trial. The treatments included soil amended with 14 different composts (prepared by shredding, adding wood shavings, cocomposting with biosolids or vermicomposting), an inorganically fertilized soil, and a control soil. All of the treatments significantly increased plant growth compared to the control, and yields of three of the amended treatments were as high as that of the inorganic fertilizer treatment. When comparing differently prepared composts to the conventional compost, it was found that cocomposting MOW with biosolids was the method which most positively influenced yields (26-41% yield increases). In the second part of this work, we evaluated the effects of the different preparation methods on compost quality, using a multivariate approach. Three main quality aspects were considered collectively in a principal component analysis: organic matter and nutrient concentrations, degradability and capacity to mineralize these nutrients, and plant growth. The model was restricted to the first and second components (PC1 and PC1) which accounted for 94% of data variance. On the resulting factorial plane, four groups were distinguished. Each of the groups was compared to the reference compost to determine quality increases or decreases. Based on this analysis, it was found that cocomposting MOW with biosolids produced the highest quality products (higher total nutrient and OM concentration, nutrient mineralization potential, and plant growth). Addition of wood shavings increased OM concentration, but reduced quality in terms of the other aspects studied. Shredding was only effective to increase product quality when it was not combined with other methods, whereas vermicomposting only increased quality when MOW was not mixed with biosolids.