电镀废水处理技术工程应用实践

针对电镀废水的特点,根据清污分流、先预处理再综合处理的原则进行合理的细化分类,对不同的水质进行分类物化处理。该处理技术具有工艺合理、可操作性好、自动化程度高等优点,处理后出水水质达到广东省《水污染物排放限值》(DB44/26-2001)二级标准。     

离心机考核测试和带式机脱水性能试验研究

为配合吉林化学工业股份有限公司 30万t乙烯工程A/O工艺废水处理工程化学污泥脱水的需要 ,进行了生产运行离心机性能考核测试和小型带式压滤机应用于化学污泥脱水的中试性能试验研究。本研究确定了小型带式压滤机最佳投泥量、投药量和产泥量等指标。达到了验收的各项技术经济指标 ,具有显著的经济和环境效益。     

Ca改性生物炭对土壤磷赋存形态影响及稳定化机制

针对湖库周边农田淹没后土壤磷释放风险控制的问题,采用共热解法制备Ca改性生物炭（Ca-BC）,通过X射线光电子能谱分析（XPS）、X射线多晶粉末衍射分析（XRD）、吸附实验和模拟培养实验等,进行Ca-BC 对土壤磷赋存形态影响和稳定化机制研究.结果表明,Ca-BC 吸附磷的过程符合Langmuir（R² = 0.940）和一级吸附动力学模型（R² = 0.961）,表明该吸附过程为化学作用主导的单层吸附,最大吸附量达到267.93 mg·g^-1.模拟培养实验表明,当Ca-BC添加量为1%时,土壤中较活跃性的交换态磷形态从7.42%下降至4.59%. XRD结果表明,Ca-BC吸附磷后出现Ca₃（PO₄）₂和Ca₅（PO₄）₃（OH）吸收峰,证明磷酸盐在生物炭表面形成较稳定的晶体沉淀.XPS分析表明,生物炭表面羰基官能团参与磷固定过程,提高了生物炭对磷的吸附能力.总体来讲,Ca-BC 添加量大于1%时,对磷的释放有较好的固定能力,具备对土壤磷释放控制的潜在应用价值.     

苏南五市秋冬季PM2.5化学组成特征和空间差异

于2020年9月至2021年2月在苏南五市(南京、苏州、无锡、常州和镇江)收集PM_2.5滤膜样品,分析了各样品中的水溶性无机离子和碳质组分.结果表明,苏南五市PM_2.5各组分中ρ(NO₃^-)均为最高[(9.54±10.1)～(12.1±11.3)μg·m^-3],比其它目标组分高约2倍以上.由于受更多道路扬尘和燃煤源的影响,常州市PM_2.5中Ca²⁺、Cl^-、OC和EC的浓度平均值高于其它4个城市.将所有目标组分浓度相加得到重构PM_2.5(r PM_2.5)浓度,发现各城市r PM_2.5浓度均由二次无机离子(NH₄⁺、NO₃^-和SO₄^2-,SNA)主导,占比高达(59.2%±11.1%)～(70.8%±9.72%),且r ...     

几种萃取剂对土壤中重金属生物有效部分的萃取效果

采用6种萃取剂:pH=7的0.01mol/L CaCl_2、pH=7.3的0.005mol/L DTPA+0.1mol/L TEA(三乙醇胺)+0.01mol/L CaCl_2O.1mol/L NaNO_3、0.43mol/L HOAc、pH=7的0.05mol/L EDTA和pH=4.65的0.5mol/L NH_4OAc+0.02mol/L EDTA浸取液.对污染土壤中的重金属Cu、Zn、Cd、Pb、的进行了萃取,并比较了萃取剂的萃取能力。实验结果表明,HOAc、EDTA以及NH_4OAc-EDTA萃取各种重金属的能力远远大于其它几种萃取剂的萃取能力,是比较理想的萃取剂。     

Jasmonic acid treatment and mammalian herbivory differentially affect chemical defenses and growth of wild mustard (Brassica kaber)

Summary. Jasmonic acid (JA) is a wound-related hormone found in most plants that, when applied exogenously, can induce increases in levels of chemical defenses in patterns similar to those induced by mechanical damage or insect feeding. Relative to responses to insect and pathogen attack, chemical responses of herbaceous plants to mammalian herbivore attack have been little studied. In a field experiment, we compared the effects of JA treatment and naturally occurring mammalian herbivory on the expression of trypsin inhibitors, glucosinolates, peroxidase activity and growth of wild mustard (Brassica kaber). Exogenous JA significantly increased trypsin inhibitor activity and glucosinolate concentration, and moderately increased peroxidase activity in the eighth true leaves of five-week-old plants, relative to untreated controls. In contrast, levels of these chemical defenses in the eighth true leaves or in regrowth foliage of plants that had ∼80% of their leaf area removed by groundhogs (Marmota monax) did not differ from that in undamaged and untreated controls. Although exogenous JA significantly elevated levels of chemical defenses, it did not affect height of plants through the season and only slightly reduced time to first flower. Groundhog herbivory significantly reduced height and delayed or abolished flowering, but these effects were not substantial unless coupled with apical meristem removal. We hypothesize that the lack of effect of groundhog herbivory on chemical defenses may be due in part to the speed and pattern of leaf area removal by groundhogs, or physiological constraints caused by leaf area loss. Despite having no effect on chemical defense production, leaf area loss by groundhogs was more costly to growth and fitness than the effects of JA application in this study, but only substantially so if coupled with apical meristem removal. We suggest that in general, costs of defense production in plants are likely to be minimal when compared to the risk of losing large amounts of leaf area or primary meristematic tissue. Thus, if they are effective at deterring herbivory, the benefits of inducible defense production likely outweigh the costs in most cases. Received 20 December 2000; accepted 3 May 2001     

Lignoid chemical defenses in the freshwater macrophyte Saururus cernuus

Summary. Chemical defense against herbivores has rarely been investigated for freshwater plants, possibly due to the common misconception that herbivory on aquatic macrophytes is low and would not select for chemical defenses. In previous work, the freshwater angiosperm Saururus cernuus was shown to be a low preference food for omnivorous crayfish despite its high nutrient value and relatively soft texture. We used feeding by the crayfish Procambarus clarkii to guide fractionation of the deterrent lipid-soluble extract of this plant, leading to the identification of seven deterrent lignoid metabolites, (–)-licarin A, (+)-saucernetin, (–)-dihydroguaiaretic acid, (–)-sauriols A and B, (–)-saucerneol, and (–)-saucerneol methyl ether. Lignans have been implicated in terrestrial plant chemical defenses as insect growth inhibitors, insect toxins, nematocides, antibacterial, and antifungal agents. However, these activities have rarely been demonstrated using ecologically relevant methodologies in terrestrial systems, and never before in freshwater systems. The widespread nature of lignans amongst very distantly related plants, along with their rich diversity of molecular structure, suggests that they could play a large role in mediating plant-herbivore interactions. In addition to the lignoid compounds we identified, there were other compounds present in low concentration or unstable compounds that were deterrent, that did not appear to be lignans, but that we were unable to identify. This plant thus appears to be defended by a complex mixture of natural products. Received 6 June 2000; revised 23 August 2000; accepted 2 September 2000     

赣南小流域的水文地球化学特征和主要风化过程

对赣南花岗岩小流域进行采样、测试及分析,发现其河水含有较低的矿化度,水化学组成以Na ,Ca2 ,Cl-1和HCO-3为主,溶解性Si的含量明显较高,代表了典型硅酸盐地区河流的相应化学组成.通过Gibbs图分析,赣南流域大部分地区受大气降水的影响比较显著,"蒸发-浓缩"类型的小流域也较多.根据主成分分析和因子分析的结果,定量地估算了大气中CO2和三类岩石对河水中各种离子的贡献比例.与黄河相比,赣南流域受硅酸盐岩风化作用强烈,但主要影响因素仍是碳酸盐和蒸发盐岩,二者对赣南流域溶解质的贡献率分别为42.8%和29.2%,大气中CO2对河水溶解质的贡献率为21.4%,低于世界平均水平.主要风化反应以岩盐和方解石的溶解为主,Si/(Na* K)比值较低,说明风化反应在表生环境中进行,其产物是富含阳离子的次生矿物.     

Diet-induced chemical phytomimesis by twig-like caterpillars of Biston robustum Butler (Lepidoptera: Geometridae)

Summary. Polyphagous caterpillars of the giant geometer Biston robustum resemble the twigs of their respective food sources in color and shape. Common predatory ants, including Lasius and Formica, were often observed to freely prowl directly on caterpillars bodies, even after antennal contact. This suggests that the cuticular chemicals of the caterpillars resemble those of the twigs of the foodplants, so we analyzed both by GC and GC-MS. The chemical compositions differed among caterpillars fed on a cherry, Prunus yedoensis, a chinquapin Castanopsis cuspidata, and a camellia Camellia japonica. The cuticular chemicals of the caterpillars resembled those of their corresponding food sources. When the caterpillar diets were switched from the cherry to camellia or chinquapin at the 4^th instars, the caterpillars cuticular chemicals changed after molting to resemble those of their respective foods. Caterpillars also changed their cuticular chemicals when they perched on cherry twigs and fed on camellia or chinquapin leaves, but not when they perched on camellia or chinquapin twigs and fed on cherry leaves. The chemical similarities between the caterpillars and the twigs were due to the digestion of host leaves, which indicates that this is a diet-induced adaptation.     

UV-B辐射增强对小麦籽粒化学组分的影响

在自然光照射条件下 ,研究了UV B辐射增强对小麦籽粒中可溶性糖、淀粉、赖氨酸、蛋白质等化学组分及其相互转化的影响 .结果表明 :增加 0 2 5W·m- 2 的UV B辐射使灌浆期的小麦籽粒中可溶性糖含量显著高于对照 ,淀粉含量变化幅度增大 ,赖氨酸含量下降速度较快 ,成熟期总蛋白质含量增加 .增加 0 75W·m- 2 的UV B辐射能降低成熟籽粒中可溶性糖和淀粉的含量 ,增加赖氨酸及总蛋白质的含量 .