The determination of partition coefficients of organic compounds in technical products and waste waters for the estimation of their bioaccumulation potential using reversed phase thin layer chromatography

Reversed phase thin layer chromatography (RPTLC) has been investigated for the estimation of octanol/water partition coefficients (P), an important parameter for the prediction of the environmental behaviour of organic chemicals. A strong correlation between P derived from the traditional octanol/water system and RPTLC has been established over five orders of magnitude. RPTLC data are likewise correlated to results obtained by high performance chromatography (HPLC). Due to the low costs, simplicity and separation power RPTLC is especially suited for the investigation and screening of mixtures of compounds before more complicated tests are involved.

Results from a round robin test on the determination of partition coefficients by HPLC, RPTLC and the batch method indicate the simplicity and accuracy of the RPTLC technique. Applications of the RPTLC‐technique on technical products and industrial waste waters are described.     

高氨氮浓度下改良型倒置A~2/O工艺的脱氮性能研究

针对高氨氮生活污水,设计了一种新型的脱氮除磷工艺。该工艺是对传统倒置A~2/O工艺的改进,它采用了后置预缺氧区以提高系统的脱氮效果。试验探讨了工艺关键因素与脱氮效果的相关性。试验表明水力停留时间为25 h,内回流比为200%,DO浓度在2 mg/L时,对NH_3-N、TN、TP的去除率分别可达96.17%、73.83%和92.38%。     

A test of male mating and hunting success in the kestrel: the advantages of smallness?

We tested female choice for male wing and tarsus length and body mass in the kestrel (Falco tinnunculus), a species in which males average about 10% smaller than females. We also studied how male characters are related to their hunting success. In the laboratory, females preferred lighter males with shorter tarsi as mates, if the difference in those characters between competing males was larger than average. Lighter and shorter-winged males seemed to be better hunters than heavier and longer-winged males. Field observations in a year in which voles were scarce suggested that shorter-winged males were also better food providers in courtship feeding than longer-winged males,although in good vole years such a relationship was not found. We argue that females may prefer to pair with smaller males, because they have higher flight performance and better hunting success than heavier males. By doing so, females may gain direct breeding advantages. We conclude that both female choosiness and the hunting efficiency of males well contribute to reversed sexual size dimorphism (RSD, females larger than males) in the kestrel. Received: 18 July 1995/Accepted after revision: 17 August 1996     

The Influence of Tip Leakage Flow on Flowfields in a Highly Loaded Transonic Rotor with Forward Sweep

A three-dimensional numerical simulation on a highly loaded transonic rotor with zero, 0.2 mm, 0.3 mm, and 0.5 mm tip gap, respectively, is performed in this article. The flowfields above 60% span of transonic rotors are affected by leakage flow, but the stall margin of rotor has obviously improved with small tip gap. Typical leakage vortex structures with double cores are generated by the interaction of incoming flow, leakage flow, and second flow in flowfields, and then the two vortex cores merge into a stronger one in front of shock. The shape of passage shock changes seriously by strong leakage vortex after interaction and a large low-velocity region generates behind shock in tip region. The blockage, produced by leakage flow and boundary layer separation, induces detached shock wave near leading edge of rotors and triggers the rotating stall of compressor. However, with tip gap increasing, the blockage produced by leakage flow tends to be dominant in occurrence of rotating stall. Once the tip clearance adds to 0.5 mm, vortex breakdown in tip region of rotor appears and the flow deteriorates drastically, which aggravates the onset of stall in rotor.     

ABEI-H2O2-Cr(Ⅲ)体系反相流动注射化学发光法测定水中Cr(Ⅲ)

采用反相流动注射化学发光分析方法对ABEI-H_2O_2-Cr(III)发光体系进行了研究,并用于天然水Cr(III)的测定,获得了满意结果.本法的线性范围为1×10~(-10)g/ml—8×10~(-6)g/ml,检出限为4.5×10~(-11)g/ml,相对标准偏差为1.1％.     

反相流动注射法测定海水中磷酸盐

建立了反相流动注射-结晶紫-磷钼杂多酸离子缔合体系测定海水中磷酸盐的方法,确立了最佳试验条件,有效解决了海水的盐度干扰问题.方法线性良好,检出限为0.1 μg/L,精密度和准确度均符合要求,且流路简单,操作方便,可用于现场自动分析.     

倒置A/A/O工艺在城市污水处理中的应用研究

通过对常州市城北、清潭两座城市污水处理厂的倒置A／A／O工艺，采用不同的控制参数运行和相应的试验表明：(1)倒置A／A／O工艺对城市污水中有机物、氮和磷都具有较好的处理效果，出水水质达到《城镇污水处理厂污染物排放标准))(GBl8918—2002)一级标准中的A级标准；(2)推荐的相应控制运行参数为：污泥回流比控制在75～150％，气／水比值控制在3．0～5．0；生化反应池MLSS保持在2．50～3．50g／L，水力停留时间为10h，SRT控制为7～10d左右，生化反应池好氧段DO保持在3mg／L；(3)在进水TP浓度较低(≤2．0mg／L)的条件下，可以省略厌氧段，采用缺氧／好氧(A／O)方式运行。