石灰湿法脱硫过程反应机理的研究

采用模拟烟气对石灰湿法脱硫过程反应机理进行研究 ,研究表明 ,石灰湿法脱硫过程反应机理不仅与脱硫液初始和终点pH值有关 ,而且还与烟气中SO2 浓度密切相关     

利用pH值梯度研究建筑砂浆的酸蚀程度

在两种不同ｐＨ值模拟酸雨和３种浸泡时间条件下，据ｐＨ值梯度测定了各类保护剂处理建筑砂浆试件的酸化层厚度，从而判定保护剂的保护效果，了解酸蚀程度。并分析了影响酸化层厚度的因素。     

焙烧温度对铁覆膜砂IOCS吸附Cr(VI)的影响

采用序批试验研究了焙烧温度对铁覆膜砂(Iron Oxide Coated Sand,IOGS)吸附6价铬Cr(VI)的吸附平衡和吸附速率的影响.结果表明,铬在IOCS上的吸附平衡符合Langmuir吸附模型.低温制备IOCS具有较高吸附容量且对pH不敏感.110℃制备IOGS在pH 7的最大吸附容量(0.181 mg·g-1)远高于660℃制备10CS(0.023 m8·8-1).吸附过程符合准二级动力学模型.吸附速率随焙烧温度提高而下降.     

海水、大气化学演化对动物起源和进化方向的制约

动物的起源主要依赖于氨基酸等有机小分子在海水中能否进行脱水缩合反应而生成生物高分子，后者则依赖于海水pH值升高和大气CO2浓度降低的历史演化进程。有机小分子只有在海水pH值演化到近中性，即寒或纪时彼此才能发生脱水缩合反应而合成生物高分子。只有大气CO2分压降到1000Pa以下，即泥盆纪以后，陆地上才能出现稳定的土壤层和植物，动物也才能从海洋扩展到陆地。随后大气CO2浓度继续降低导致了气温下降和植物生长率的衰减，促使动物进一步演化。     

玉溪市中心城区酸雨变化趋势分析

以1991年至2000年实测数据为依据，揭示了玉溪市中心城区10年来酸雨的变化规律及其发展趋势。     

低pH对草鱼血液酸碱平衡的影响

研究了低pH(6.0—4.0)对草鱼血液酸碱平衡、p_(o2)及p_(co2)的影响,结果表明,低pH引起草鱼严重的酸血症.亚致死pH(6.0—5.0)时,血液酸碱平衡的影响主要表现为碱贮备[HCO_3]的丧失,血液pH的明显下降经机体缓冲调节可趋于稳定.致死低pH(4.0)时,血液pN和[HCO_3]下降均非常显著,并在96h内随酸化时间延长而日趋严重.仅在pH≤4.0的酸水中草鱼存在低氧症影响问题.草鱼是一种酸敏感性鱼类,为确保成鱼在天然水体的生存和繁育,水质pH至少应维持在6.0以上.     

Influence of no-tillage on the distribution and lability of phosphorus in Finnish clay soils

No-tillage (NT) is a method adopted to reduce erosion and particulate phosphorus (P) load from arable land to watercourses. However, it has been found to increase the loss of dissolved P with surface runoff, but the reasons for that have rarely been examined in detail. The objective of the present study was to determine the chemical factors explaining this response by investigating the impact of NT on the type and distribution of P reserves as well as on organic carbon (C) in the 0–35 cm topsoil layer of clay soil profiles (Vertic Cambisols). Soil samples were taken from two experimental fields (Jokioinen and Aurajoki) at 0–5, 5–20 and 20–35 cm depths in conventionally tilled (CT) and non-tilled (for 4–5 years) plots. The plots had been cultivated and fertilized according to the common field practices in Finland (15–18 kg P and 100–128 kg N ha⁻¹ year⁻¹).Inorganic and organic P reserves characterized by a modified Chang and Jackson fractionation procedure were not significantly affected by the cultivation methods. However, in the uppermost soil layer (0–5 cm) in NT of the Jokioinen field, the labile P determined by water extraction (P_w) increased significantly, whereas the increase in P extracted with acid ammonium acetate (P_AAC) remained statistically insignificant. The increase in labile P coincided with a significant increase in organic carbon (C), which supports the theory that competition between organic anions and phosphate for the same sorption sites on oxide surfaces will enhance the lability of soil P. In the Aurajoki field with distinct soil cracking, P_w and P_AAC were not affected by NT in the uppermost soil layer, but they increased in the deepest soil layer (20–35 cm) concomitantly with an increase in Al-bound P and organic C. However, the increases were not statistically significant. In both fields, soil acidification due to the repeated application of N fertilizers at a shallow soil depth as well as the accumulation of organic C lowered pH of the uppermost soil layer in NT compared to the deeper soil layers. The results indicated that even short-term NT can increase the labile P in clay soil. However, further studies are needed to assess the long-term changes in lability of surface soil P and, consequently, the possible need for readjustment of the fertilization level in NT.     

金沙江对硫酸的缓冲性能分析

本文分析了金沙江对硫酸的缓冲特征，建立了江水的缓冲曲线方程，并且验证了此方程的有效性，证明用此方程预测硫酸进入金沙江后江水pH值的变化情况，其预测准确度在0.2个pH单位内。     

基于pH值和ORP的跳水池池水处理系统的自动控制

为改善跳水池水质的化学安全性和生物学稳定性,保障运动员、教练员以及工作人员身体健康,结合长春市泅渡馆跳水池,阐述了基于pH和ORP的池水处理自动控制系统,确定了自动控制系统的控制参数及其控制范围,为健康跳水池池水处理系统的自动控制系统的设计提供了参考。     

中国西南酸雨区降水化学特征研究进展

西南酸雨区为我国主要酸雨沉降区,且是全球三大喀斯特集中分布区之一.本文将该区9个地点的降雨资料进行了总结、整理和分析,数据包括pH值和主离子成分(Cl~-、SO_4~(2-)、NO_3~-、Ca~(2+)、NH_4~+、Mg~(2+)、K~+、Na~+).该地区降雨中的主要阴离子为SO_4~(2-)和NO_3~-,主要阳离子为Ca~(2+)和NH_4~+.与我国其它地区相比,其酸性离子、碱性离子和总离子浓度均普遍高于东南地区、而低于我国北方地区.西南酸雨区主要以pH值为4.5~5.6的弱酸性降雨为主,占总降雨频次的58%左右.根据酸、碱性离子的相关性、中和因子等分析结果,该区雨水中的酸性物质可能受到了碱性离子的中和作用,其中起主要中和作用的离子为Ca~(2+)和NH_4~+.将该区雨水pH值和酸、碱性离子浓度与我国其它地区进行对比研究发现,西南酸雨区降雨受到的中和作用要强于东南地区,但弱于北方地区的降雨.通过对西南酸雨区降雨中主要离子来源的分析和估算,降雨中的酸性离子SO_4~(2-)和NO_3~-主要来自于人为污染;99.7%的Ca~(2+)和84.0%的Mg~(2+)为陆源贡献,这可能与西南地区碳酸盐岩广泛分布有关.