过氧化氢酶活性及活性抑制的紫外分光光度测定

在体内实验条件下，测定了鲤鱼肝脏过氧化氢酶的活性。实验结果表明，过氧化氢酶的紫外分光光度法是可靠的，活性抑制结果表明，对－二硝基苯对鲤鱼肝脏过氧化氢酶无有明显的抑制作用。鲤鱼肝脏过氧化氢酶可作为一项指标用于生态毒理学研究。     

衍生化气相色谱法测定黄磷诱发氧化水中苯酚降解产物

利用衍生化气相色谱法对黄磷诱发氧化苯酚降解产物进行了研究，在磷酸存在下，以甲醇作酯类衍行生试剂，分别和ＳＥ－５２和ＨＰ－１７石英毛细管双柱结合ＧＣ－ＭＳ进行分离定性定量，黄磷诱发氧化苯酚降解产物以羧酸为主，在反应温度５０℃时，表现为一级反应特征，速率常数（Ｋ）：０．０７７ｍｉｎ＾－１，半衰期（ｔ１／２）：９．０ｍｉｎ。     

Fenton试剂处理选矿废水机理研究

研究了用Fenton试剂处理选矿废水中残余的黄药,分别考查了氧化时间、反应初始pH值、Fe2+浓度及H2O2用量对黄药降解效果的影响,用正交试验确定了4个因素的最好条件。结果表明:初始pH值和H2O2用量是影响去除效果的主要因素;氧化时间为60 m in,反应初始pH=4,[Fe2+]=20 mg/L,[H2O2]=20 mg/L,黄药的浓度为125 mg/L时,黄药的去除率达到99.5%;初步探讨了Fenton试剂净化废水中黄药的机理是.OH自由基先将黄药氧化为过氧化黄原酸盐,再将其氧化为CO2,黄药得到去除。     

Toxicity of copper on rice growth and accumulation of copper in rice grain in copper contaminated soil

Pot soil experiments showed that copper (Cu) is highly toxic to rice. Rice grain yields decreased exponentially and significantly with the increase of soil Cu levels. Rice grain yield was reduced about 10% by soil Cu level of 100 mg kg(-1), about 50% by soil Cu level of 300-500 mg kg(-1) and about 90% by soil Cu concentration of 1,000 mg kg(-1). Root was more sensitive to soil Cu toxicity than other parts of rice plant at relatively lower soil Cu levels (less than 300-500 mg kg(-1)), but the growth of whole rice plant was severely inhibited at high soil Cu levels (300-500 mg kg(-1) or above). Cu concentrations in rice grain increased with soil Cu levels below 150-200 mg kg(-1), but decreased with soil Cu levels above 150-200 mg kg(-1), with peak Cu concentration at soil Cu level of 150-20 mg kg(-1). Cu was not distributed evenly in different parts of rice grain. Cu concentration in cortex (embryo) was more than 2-fold that in chaff and polished rice. More than 60% of the Cu in grain was accumulated in polished rice, about 24% in cortex (embryo), and about 12% in chaff. So, about 1/3 of the Cu in rice grain was eliminated after grain processing (chaff, cortex and embryo was removed).     

Screening 31 endocrine-disrupting pesticides in water and surface sediment samples from Beijing Guanting reservoir

For screening 31 potential or suspected endocrine-disrupting pesticides in water and surface sediments, a multiresidue analysis method based on gas chromatography with electron capture detection (GC/ECD) was developed. Solid phase extraction (SPE) technology with Oasis^® HLB cartridge was also applied in sample extraction. The relevant mean recoveries were 70–103% and 71–103% for water and sediment, respectively. Relative standard deviations (RSD) are 2.0–7.0%, 4.0–8.0% for water and sediment, respectively. Thirty one pesticides (-HCH, β-HCH, γ-HCH, δ-HCH, hexachlorobenzene (HCB), aldrin, heptachlor, endosulfan I & II, p,p′-DDD, o,p′-DDT, p,p′-DDT, p,p′-DDE, endrin aldehyde, endosulfan sulphate, methoxychlor, hepachlor epoxide, -chlordane, γ-chlordane, dieldrin, endrin, dicofol, acetochlor, alachlor, metolachlor, chlorpyriphos, nitrofen, trifluralin, cypermethrin, fenvalerate, deltamethrin) in water and surface sediment samples from Beijing Guanting reservoir were analyzed. Concentrations of pesticides ranged from 7.59 to 36.0 ng g⁻¹ on a dry wt. basis for sediment samples, from 279.3 to 2740 ng l⁻¹ for pore waters and from 48.8 to 890 ng l⁻¹ for water samples, respectively, with a mean concentration of 10.7 ng g⁻¹ in sediment, 735 ng l⁻¹ in pore water and 295 ng l⁻¹ in water, respectively. The data obtained provides information on the levels and sources of endocrine-disrupting pesticides in Guanting reservoir. These results underscore the need to improved environmental protection measures in order to reduce the exposure of the population and aquatic biota to these endocrine-disrupting compounds.     

不同混凝剂处理低温低浊水

针对低温低浊水处理难度大的问题进行了一系列的混凝实验,实验结果表明,随着混凝剂投加量的增加,剩余浊度呈现先降低后升高的趋势,单独使用HPAC时,剩余浊度在投加量为14 mg/L时达到最低(2.39 NTU)。pH值对余铝含量具有重要的影响,3种铝系混凝剂均在pH=7.0时余铝含量达到最低。AlCl3对水中有机物的去除率较其他3种混凝剂低。絮体形成与破碎受搅拌强度的影响很大,当破碎强度增加到50 r/min,使用PACl、HPAC、FeCl3作混凝剂时絮体粒径下降不明显,当破碎强度增加到100 r/min时,絮体粒径有明显的下降。破碎结束后,絮体粒径有所恢复,但是并不能增长到破碎前的粒径。PACl、HPAC以及FeCl3形成的絮体的沉降性较好,上覆水浊度下降较快,经过3 h的沉降后,剩余浊度分别达到1.82、1.44和0.97 NTU。     

聚乙烯醇/超细羽绒粒子共混膜的制备及其染料吸附动力学

为了改善并更好地研究聚乙烯醇的染料吸附性能,制备了不同超细羽绒粒子含量的聚乙烯醇/超细羽绒粒子共混膜,并将其用于对活性艳红X-3B染料的吸附。结果表明,随着超细羽绒粒子含量的增加,聚乙烯醇/超细羽绒粒子共混膜表面粗糙程度增大。当超细羽绒粒子的质量分数为27.8%时,K/S值最大,染料吸附性能最好,其吸附效果比纯聚乙烯醇膜提升约54.5%。动力学研究结果表明,伪二级动力学模型能更好地描述聚乙烯醇/超细羽绒粒子共混膜对染料的吸附。     

秸秆成型燃料锅炉污染物排放规律试验研究

根据锅炉烟尘测试方法(GB 5468-91)及锅炉大气污染物排放标准(GB 13271-2001),在不同风门的工况下,分别对设计的双层炉排秸秆成型燃料锅炉污染物排放规律进行试验.试验表明,在较好工况下,双层炉排锅炉排烟中CO等中间产物及烟尘含量低于单层炉排锅炉,其排烟中CO、NOx、SO2和烟尘浓度等指标远远低于燃煤锅炉,符合国家关于工业锅炉大气污染物排放标准要求,有较好环保效益.     

Photocatalytic oxidation of heptane in the gas-phase over TiO2.

In this paper, gas-phase photocatalytic oxidation (PCO) of heptane over UV-illuminated TiO2 was carried out at ambient temperature in a batch reactor. Complete oxidation of heptane with almost stoichiometric production of CO2 and H2O was observed. The intermediates detected were propanal, butanal, 3-heptanone, 4-heptanone and carbon monoxide. A scheme of the possible mechanism for PCO of heptane over TiO2 was suggested. Langmuir-Hinshelwood kinetics equation was obtained from the results at different initial concentrations of heptane, oxygen, moisture and light intensity. The photocatalytic activity of TiO2 can be sustained indefinitely. This can be attributed to the production of water in the system, which can replenish the consumed hydroxyl radicals.     

惠州市土地资源及其利用保护

从惠州市土地资源及其利用现状入手，分析其在土地资源利用上存在的耕地面积锐减、土地资源承载力下降、耕地土壤肥力下降、水土流失严重以及土壤和农作物被污染等问题，提出相应的土地资源利用和保护措施。