碳酸钾添加比例对玉米秸秆生物炭表面特性的影响

在600℃的热解温度下通过添加不同比例的碳酸钾制备活性生物炭。对比分析了碳酸钾活化生物炭(KBC)和普通生物炭(BC)的特性,包括生物炭红外光谱特征、表面官能团、比表面积和孔径分布及吸附动力学过程等。结果表明,经碳酸钾活化的生物炭比表面积大为提高,最高达到566 m2 g-1(KBC-2-600),而普通生物炭(BC600)的比表面积仅为86.8 m2 g-1,KBC600系列的介孔容积和微孔容积均显著高于BC600,介孔容积平均扩大了16倍,微孔容积平均扩大了4倍,同时提高了微孔率。经碳酸钾活化的生物炭表面官能团的数量和饱和度发生改变,在1 256 cm-1~3 414 cm-1处,官能团的总体含量均低于普通生物炭,酯类羰基消失,形成氢键的能力减弱,非饱和醚类增加,芳香性和非极性提高,此表面特征更有利于吸附非极性芳香类污染物。对萘吸附的动力学实验表明,BC600和KBC-4-600均适合以二级动力学模型拟合,经碳酸钾活化后,生物炭的吸附性能提高,颗粒内扩散模型拟合结果表明,经碳酸钾活化后,生物炭内部孔隙复杂程度和数量均得到提高。碳酸钾活化的生物炭表面性质优良,作为高效吸附剂用于修复非极性芳香类污染有很大潜力。     

Aggregation of under canopy and bare soils in a Mediterranean environment affected by different fire intensities

Soil macroaggregation in relation to soil organic matter (SOM) and calcium carbonate (CaCO₃) content was studied, before and after experimental fires of different intensities, in two environments (under canopy and on bare soil). In 1995, two experimental fire treatments, based on the addition of different biomass amounts, were applied on a set of nine plots at the Permanent Field Station of La Concordia (Valencia, Spain). Three plots were burned with high intensity fire (T1), three with moderate intensity (T2) and three plots were left unburned to be used as control treatment (T3).     

碳酸盐岩与碎屑岩母质土壤地球化学特征及质量差异

为研究云贵高原南部碳酸盐与碎屑岩两类型不同时代母质的残坡积土壤的地环质量,找寻两种类型母质间土壤元素的差异,了解两母质类型土壤元素的丰度及环境质量概况,为区域农业的持续发展和长远规划提供理论依据,以滇东南广南县南屏至珠街等地区不同时代母质的残坡积土壤为研究对象,通过调查、采样和检测,对两类型土壤的地化特征、元素丰度和环境质量进行分析评价。结果表明:A类土从母质风化至成土过程中元素活跃程度高、流失量多、风化程度好,成土后元素富集量大,土壤元素丰度高,但土壤环境质量差;B类土壤元素含量低,元素多贫乏,但环境质量良好。B类土元素丰度稍差,土壤环境质量良好,A类土元素丰度高,土壤环境质量差。     

A STUDY ON HYDRATE AND CARBONATE RESISTANCE OF CONCRETE WITH GANGUE CEMENT

This paper studies the hydrates and the characteristicsof micro-structure of concrete with gangue cement before and after carbonation under different curing conditions.It is compared with Portlandcement concrete,and the carbonate resistance of concrete with ganguecement is studied too.     

Clay,Organic Carbon,Available P and Calcium Carbonate Effects on Phosphorus Release and Sorption–Desorption Kinetics in Alluvial Soils

Information on phosphorus (P) release kinetics and sorption–desorption in soils is important for understanding how quickly reaction approaches equilibrium and replenishes the depleted soil solution. Laboratory experiments were conducted to study the P release and sorption–desorption kinetics in soils differing in clay, soil organic carbon (SOC), available P, and calcium carbonate (CaCO₃) contents. Phosphorus release from soils proceeded in two phases: initially faster phase followed by a slower phase as equilibration progressed. Elovich equation (R² ≥ 0.97**) described well the P release versus time data. P release coefficients for power function were significantly correlated with available P and SOC. Freundlich sorption constants increased with increase in clay and CaCO₃ content. With increase in SOC and available P concentration in soils, substantial reduction in sorption constants was observed. It was concluded that for efficient P management, it is important to take into account soil texture, the existing soil P level, SOC content, and soil calcareousness.     

植酸对碳酸盐绿锈转化的影响

为研究植酸（IHP）对绿锈转化过程及机制的影响,通过空气氧化法合成碳酸盐绿锈[GR1 （CO₃^2-）],并利用X射线衍射、衰减全反射-傅里叶变换红外光谱、高分辨透射电子显微镜、扫描电子显微镜和能量色散X射线能谱对体系中的固体产物进行分析表征。研究表明：不存在IHP时GR1（CO₃^2-）在5 h左右完全转化为针铁矿,而存在IHP时GR1（CO₃^2-）的转化会受到抑制。在0~0.5mmol·L^-1的IHP浓度范围内,GR1 （CO₃^2-）的转化产物为针铁矿,而当IHP浓度高于1.0 mmol·L^-1时,GR1 （CO₃^2-）的转化产物为针铁矿和高铁绿锈。IHP对GR1（CO₃^2-）转化机制的影响与其浓度有直接关系,在低浓度IHP（0~0.5 mmol·L^-1）条件下,GR1（CO₃^2-）转化过程只涉及溶解-氧化-沉淀（DOP）机制;而高浓度IHP（1.0~5.0 mmol·L^-1）体系中,固态氧化（SSO）机制占主导地位,在其转化过程中,一部分GR1（CO₃^2-）通过溶解再沉淀机制转化为针铁矿,一部分GR1（CO₃^2-）通过原位脱质子反应转化为高铁绿锈。此外,在GR1 （CO₃^2-）转化过程中,IHP在GR1 （CO₃^2-）及其转化产物表面会形成内圈络合物和植酸（亚）铁沉淀。总体而言,IHP会抑制GR1 （CO₃^2-）的溶解再沉淀转化机制,阻碍针铁矿的结晶和晶体生长,且抑制作用与IHP浓度呈正相关。     

咸水水质对刀额新对虾生长的影响

本文通过对刀额新对虾仔虾的急性中毒试验和水型生长试验,对刀额新对虾仔虾在不同类型咸水中的生存、生长进行了研究。结果表明：(1)水质中的碳酸盐碱度和pH值对刀额新对虾仔虾的致死作用存在着交互作用,碳酸盐碱度96h LC50值为15．45mmol／L;(2)刀额新对虾仔虾能生长在一些S^AaⅡ、Cl^AaⅡ、Cl^MaⅢ等咸水水型中。     

Combined effects of water exchange regimes and calcium carbonate additions on growth and survival of hatchery-reared juvenile spotted babylon (Babylonia areolata Link 1807) in recirculating grow-out system

To determine a suitable culture environment to maximize growth and survival, the hatchery‐reared juvenile spotted babylon, Babylonia areolata, were held in plastic rearing tanks at four calcium carbonate additions of 0, 100 and 300 g tonne^?1, and four water exchange regimes of 0‐, 15‐, 30‐ and 60‐day intervals in a recirculating grow‐out system for 120 days. The results clearly showed that growth was greatest between water exchange regimes of 15‐ and 30‐day intervals and all calcium carbonate additions, with water exchange regimes of 0‐ and 60‐day intervals resulting in poor growth. Final survival was highest between water exchange regimes of 15‐ and 30‐day intervals, and all calcium carbonate additions, with water exchange regimes of 0‐day intervals and all calcium carbonate additions resulting in high mortalities. This study showed that water exchange regimes had a stronger influence on the growth of juvenile B. areolata than calcium carbonate additions. It is recommended that B. areolata juveniles be maintained within the water exchange regimes range of 15–30‐day intervals and at calcium carbonate additions between 0 and 500 g tonne^?1, providing optimum conditions for production of this species in a recirculating grow‐out system.     

碳酸钾添加比例对玉米秸秆生物炭表面特性的影响

在600 oC的热解温度下通过添加不同比例的碳酸钾制备活性生物炭。对比分析了碳酸钾活化生物炭（KBC）和普通生物炭（BC）的特性,包括生物炭红外光谱特征、表面官能团、比表面积和孔径分布及吸附动力学过程等。结果表明,经碳酸钾活化的生物炭比表面积大为提高,最高达到566 m2?g-1（KBC-2-600）,而普通生物炭（BC600）的比表面积仅为86.8 m2?g-1,KBC600系列的介孔孔容和微孔孔容均显著的高于BC600,介孔孔容平均扩大了16倍,微孔孔容平均扩大了4倍,同时提高了微孔率。经碳酸钾活化的生物炭表面官能团的数量和饱和度发生改变,在1 256 cm-1～3 414 cm-1处,官能团的总体含量均低于普通生物炭,酯类羰基消失,形成氢键的能力减弱,非饱和醚类增加,芳香性和非极性提高,此表面特征更有利于吸附非极性芳香类污染物。对萘吸附的动力学实验表明,BC600和KBC-4-600均适合拟二级动力学模型拟合,经碳酸钾活化后,生物炭的吸附性能提高,颗粒内扩散模型拟合结果表明,经碳酸钾活化后,生物炭内部孔隙复杂程度和数量均得到提高。碳酸钾活化的生物炭表面性质优良,作为高效吸附剂用于修复非极性芳香类污染有很大潜力。     

次生碳酸盐结核的物质组成及元素富集特点

以黄土高原南缘武功次生碳酸盐结核为研究对象,通过分析各级结核中有机质和碳酸盐的分布特征、粒度及矿物组成,结合酸溶性元素分析,明确次生碳酸盐结核的形成过程及元素富集特点。结果表明,黄土高原南缘武功全新世古土壤发育期间形成的碳酸盐结核主要由粒径250μm结核和粒径50μm结核相互胶结而成。次生碳酸盐首先在粘粒及细粉粒表面淀积,土壤颗粒间的孔隙随着淀积的进行逐渐被次生碳酸盐填充,碳酸盐结核逐渐形成并不断生长。随着结核的生长,碳酸盐含量大幅增加,从而稀释降低了有机质含量;同时,其颗粒组成逐渐变粗,粘土矿物含量减少。各级结核中酸溶性元素均以钙(61.03~207.36g/kg)为主,且与碳酸盐含量呈正相关,因此,CaCO_3是结核中碳酸盐的主要形式。此外,酸溶性元素中含有一定量的次生无定形硅(8.90~10.70g/kg)和铝(2.78~5.06g/kg)以及粘土矿物中的钾(3.34~4.32g/kg)和镁(2.22~3.64g/kg);同时含有少量可溶性盐中的钠(0.70~0.85g/kg)。