废水中硫酸盐生物还原影响因素的研究

本文对硫酸盐还原菌还原青霉素废水中的ＳＯ２－４进行了研究,试验结果表明：进水ＳＯ２－４浓度、ＣＯＤ／ＳＯ２－４及ＳＯ２－４负荷是影响硫酸盐还原效果的主要因素。在中温（３５℃±１℃）条件下,当反应器进水ＳＯ２－４浓度为１６００ｍｇ／Ｌ,ｐＨ为７～９,ＣＯＤ／ＳＯ２－４大于３,ＳＯ２－４容积负荷为７．５ｋｇ／（ｍ３·ｄ）时,ＳＯ２－４去除率可达８５％。     

硫酸盐对木糖废水厌氧处理的影响

在中温35℃±1℃条件下,对含高浓度硫酸盐的木糖生产废水进行了厌氧消化研究,主要研究了pH值和COD/SO42-比值等因素对COD,、SO42-去除率、以及它们之间关系的影响.实验证明,投加铁离子是解除硫化物抑制的有效方法;在中性及偏酸环境中有利于COD的去除;当COD/SO42-的比值大于2.78时,COD的去除率几乎不受COD/SO42-比值的影响.     

长期浸泡作用下硫酸根离子在混凝土中的传输规律试验研究

针对受硫酸盐溶液长期浸泡作用的混凝土,制备对应于混凝土所处环境类别和作用等级中度、严重和非常严重的硫酸钠溶液,硫酸根浓度分别为800、6 000、50 000 mg/L。将强度等级为C40的混凝土试块在硫酸钠溶液中浸泡至不同龄期,采用钻芯、分层切片、研磨提取水泥石粉末样本进行化学分析,研究了硫酸根离子在混凝土内的分散和传输规律。结果表明,硫酸根离子在混凝土中的传输与侵蚀溶液浓度和侵蚀龄期存在较复杂的相关性。在侵蚀龄期较短时,硫酸根离子在混凝土中的传输速度较快,侵蚀深度较大。随着侵蚀龄期的增长,硫酸根离子主要集中在混凝土浅层范围内,且随着侵蚀溶液浓度的增加浅层混凝土中的硫酸根离子含量明显增大。     

Performance and Microstructure of Ultra Low Ion Permeability Cementitious Materials

Microstructure and macro performance of Ultra Low Ion Permeability Cementitious Materials (ULIPCM) were investigated by Micro hardness, MIP and SEM EDXA. It was shown that the compressive strength of ULIPCM was more than 80 MPa, flexural strength was more than 11.0 MPa, and elastic modulus was in the range of 38.0 to 42.0 GPa at the age of 28 days; chloride diffusion coefficient was lower than 0.8×10－13m2·s－1, conductive charge for 6 hours was lower than 300 coulombs; sulfate attack resistance was good; shrinkage at the age of 28 days was lower than 400×10－6. Compared with ordinary concrete with which thickness of interfacial transition zone is 60 to 100 μm, the thickness of interfacial transition zone of ULIPCM was lower than 30 μm. Penetration paths of corrosive medium were effectively interrupted in ULIPCM. And pore structure parameters, such as porosity and the most probable pore radius of ULIPCM, were also obviously optimized in ULIPCM. Besides, few CH crystals were in the ULIPCM aggregate and the interfacial transition zone of ULIPCM. And the orientation of CH crystals was poor.     

高Zn富Se松花蛋的研制

研究了以鸡蛋为原料生产高锌富硒松花蛋的加工工艺,并着重对松花蛋中的碱度,锌盐、硒盐的添加量,茶叶用量3个影响因素进行了探讨。结果表明,硫酸锌的添加量为0.18%～0.22%,亚硒酸钠的添加量为0.1%,烧碱质量分数为6.0%～7.0%时的效果良好,茶叶的添加量对松花蛋的品质影响不显著。     

两种不同镁盐在牛粪堆肥高温期的保氮效果研究

利用恒温培养箱模拟堆肥高温期,添加硫酸镁、磷酸二氢钾和含镁废渣,研究磷酸铵镁(MAP)反应中各成分的保氮效果以及含镁废渣作为堆肥过程中氮素固定剂的可行性。结果表明:添加镁盐固定剂显著降低了堆体中的pH值,减少了氮素损失。同时添加硫酸镁和磷酸二氢钾的保氮效果最佳,添加相同比例的含镁废渣和硫酸镁的保氮效果无显著差别。含镁废渣添加量的保氮效果与其添加量成正相关,添加质量比为2%、4%、8%的含镁废渣的保氮率分别为6.15%、10.13%、19.51%。添加镁盐会提高堆体中的EC值,降低GI值,各处理均可达到腐熟。说明可以利用镁盐作为堆肥保氮固定剂,而含镁废渣因其价格低廉,更具应用前景。     

硫酸铜蓄积对日本蟳4种组织细胞超微结构的影响

通过蓄积毒性试验,研究了安全质量尝试（0.5mg.L-1）硫酸铜（CuSO45H2O）对日本蟳（Charybdis japonica）4种组织细胞（肌肉、鳃、肝胰脏和心脏）超微结构的影响。结果表明CuSO45H2O主要损伤的组织是鳃和肝胰脏,其次是心脏和肌肉。鳃细胞的损害表现为鳃丝水肿,细胞器溶解,角质层变薄,线粒体、内质网的肿胀、解体;肝胰脏细胞的主要损害特征为肝管微绒毛减少,线粒体水肿解体,内质网扩张,细胞核空泡化,核膜水肿和脂肪滴增加;心脏细胞的毒理变化为线粒体内嵴肿胀、瓦解,肌原纤维不规则,内质网溶解。安全浓度的CuSO45H2O经过16d蓄积后虽然没有导致日本蟳死亡,但已经对其体内组织细胞的超微结构产生了不同程度的影响。

     

物化法去除糖蜜酒精废水硫酸盐效果及其产气性能的比较

糖蜜酒精废水中高浓度的硫酸盐会抑制生化处理产甲烷性能。该文采用活性炭、Ba Cl2·2H2O、Ca(OH)2及铁碳微电池法对糖蜜酒精废水中的硫酸盐进行预处理,并分析了预处理前后硫酸根及化学需氧量COD的变化,同时,也分析评价了几种方法对产气性能的影响。结果表明:在500.0 g糖蜜酒精废水中加入8.0 g活性炭,硫酸根去除率达80.0%以上,且产气性能相对最好,累计产气率可达437.3 m L/g。在500.0 g糖蜜酒精废水中,根据S元素含量和Ba SO4的分子组成比例,添加70%的化学试剂Ba Cl2·2H2O,能全部去除硫酸根,累计产气率可达483.2 m L/g,产气效果相对最好,同等条件下,添加70%的Ca(OH)2,硫酸根也能全部去除,累计产气率可达436.6 m L/g。铁碳微电池处理的糖蜜酒精废水,能有效抑制硫酸根的影响,并且可以提高废水的可生化性,累计产气率为451.0 m L/g,是对照处理293.1 m L/g的1.5倍。各处理效果的产气性能排序为70%Ba Cl2·2H2O铁碳微电池8.0 g活性炭吸附70%Ca(OH)2对照组。     

Effects of incubation times and moisture regimes on pH values and exchangeable cations in acid sulfate soils as influenced by application rates of basic slag

Severe acidifications in acid sulfate soils (ASSs) have occurred worldwide due to sulfuric acidity, which requires sustainable measures for their reclamation. Accordingly, an incubation study was conducted with the topsoil of two different ASSs (Cheringa and Badarkhali) to evaluate the effects of basic slag (BS; size <1 mm, pH 9.6, Ca 20.8%, Mg 9.8%, etc.), on reduction of acidity and changes in exchangeable cations. It is noted that BS is a byproduct of steel industry in Bangladesh and can be collected almost free of charge. These soils received BS at the rate of 0 (T₀), 11 (T₁), 22 (T₂) and 33 (T₃) t ha⁻¹ under various moisture regimes (saturated condition M₁,_, i.e., 100% moisture content, wetting–drying cycles of 100 and 50% moisture M_2, and moisture at field condition M₃, i.e., 50%). The impacts of these treatments on some selected parameters in these soils were studied within 180 days of incubation. The application of BS was found to increase the pH of soils from 3.6 to 5.1 for Cheringa, 3.9 to 5.2 for Badarkhali soils at the end of incubation. These increments were more striking with the highest doses of BS under saturated moisture conditions in both of the soils. The ECe of the soils was not much influenced by the application of BS regardless of time. The treatments exerted significant (P ≤ 0.05) effects on exchangeable cations in different periods of incubation. The striking changes were recorded for the rate of increments of Ca²⁺ and Mg²⁺, which were about 2–3 times higher for Ca and more than 2 times higher for Mg²⁺ compared with the control after 180 days of incubation. These results suggest that the application of BS not only increased the Ca²⁺ to the higher amount than that of the increment of Mg²⁺ in the soils, but also improved one of the important criteria of Ca²⁺ and Mg²⁺ ratio in the soils.     

Preparation and Characterization of O-Acylated Fucosylated Chondroitin Sulfate from Sea Cucumber

Fucosylated chondroitin sulfate (FuCS), a kind of complex glycosaminoglycan from sea cucumber, has potent anticoagulant activity. In order to understand the relationship between structures and activity, the depolymerized FuCS (dFuCS) was chosen to prepare its derivates by selective substitution at OH groups. Its O-acylation was carried out in a homogeneous way using carboxylic acid anhydrides. The structures of O-acylated derivatives were characterized by NMR. The results indicated that the 4-O-sulfated fucose residues may be easier to be acylated than the other ones in the sulfated fucose branches. But the O-acylation was always accompanied by the β-elimination, and the degree of elimination was higher as that of acylation was higher. The results of clotting assay indicated that the effect of partial O-acylation of the dFuCS on their anticoagulant potency was not significant and the O-acylation of 2-OH groups of 4-O-sulfated fucose units did not affect the anticoagulant activity.