The study for polyaromatic hydrocarbons decay on Chinese coal soot particles in atmosphere

A study for the photochemical behavior of some polyaromatic hydrocarbons (PAH), for example B(a )P, B( k )F and fluoranthene in coal smoke particles was performed by using indoor Teflon smog chamber.Experiments suggest that the photochemical reaction of PAH is first order reaction and kinetic rates of some PAH were obtained. It was shown that the reaction rate constant is proportional to light intensity and water vapor concentration. Temperature and PAH loading also have influence on PAH decay rate. A model for PAH loss has been set up on the basis of the results of our experiments and the simulating results of this model suggest that coal particle PAH half lives are of the order of a period of days in winter and a few hours in summer. Other factors which may have effect on the photochemical reaction of PAH have also been discussed.     

The hierarchy and spatial characteristics of ecosystems: A reconsideration of the ecosystem concept (II)

This paper, based on the autonomy concept, continues to investigate hierarchical forms and spatial structure of ecosystems. The former can lead to limits for the selection of the component parts of an ecosystem and a distinction between its endogenous and exogenous variables; and the latter can be lead to a hypothesis of the space of an ecosystem: the space of an ecosystem = its habitat area + supporting area + impact area, and two characteristics of ecosystems, space-overlapping and the area of ecosystem space, have been further studied referring to human activities.     

Effects of Ca2+ ions antagonistic to Al3+ ions poisoningin root growth , cell division and nucleolusin root tip cells of Allium cepa

The effects of different aluminium chloride concentrations together with varying calciumchloride concentrations on root growth, cell division and nucleoli in root tip cells of Allium cepa werestudied. The concentrations used for aluminium chloride were 10^-4, 10^-3 and 10^-2 mol/L ; and for calcium chloride were 10^-5 , 10^-4 , 10^-3 and 10^-2 mol/L, respectively. The results showed that after thetreatments with 10^-2 to 10^-3 mol/L Al³⁺ , root growth was severely inhibited , a large nurnber of thecells with c-mitosis were induced and the nucleolar material was extruded from the nucleus into the cytoplasm. However , the treatments with 10^-2 to 10^-3 mol/L of Al³⁺ together with 10^-2)to 10^-5 mol/LCa²⁺ suggested that Ca²⁺ gave the obviously protective effects against Al³⁺ poisoning in root growth.cell division and nucleoli of the root tip cells in A. cepa. The possible mechanism of these protective effects of Ca²⁺) is also briefly discussed.     

Effects of lead , cadmium , mercury chlorides and aquaticenvironmental samples on the growth of Escherichia coli

In this paper it was reported that PbCl₂ , CdCl₂ , HgCl₂, and aquatic environmental samples containing Al, Cd, Cu, Pb, Sr, Zn and other heavy metal ions as well as organic chemicals suppressed thegrowth of E. coli only at higher exposed concentrations. The stimulative effects of PbCl₂ and HgCl₂ on thegrowth of E. coli were clearly showed at lower concentrations and longer time. It suggested that the toxic effects of heavy metal ions and other pollutants on the growth of E. coli are variable according to the differentexposed levels.     

β修正分光光度法测定水中铍

在十六烷基吡啶存在下，Ｂｅ（Ⅱ）与铬天青Ｓ（ＣＡＳ）作用生成棕红色络合物。本文研究了用β修正光光度法分析水中痕量Ｂｅ。通过对样品测定，相对标准偏差ＲＳＤ≤５％，铍加标回收率为９０．７％－１０７％，铍最低检测浓度５μｇ／Ｌ，该方法适合工业废水等各环境水体分析。     

The buffering effects of aquatic sediments against acidic deposition

ＴｈｅｂｕｆｆｅｒｉｎｇｅｆｆｅｃｔｓｏｆａｑｕａｔｉｃｓｅｄｉｍｅｎｔｓａｇａｉｎｓｔａｃｉｄｉｃｄｅｐｏｓｉｔｉｏｎＬｉａｏＢｏｈａｎ；ＴａｎｇＨｏｎｇｘｉａｏ（ＲｅｓｅａｒｅｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ...     

Assay of some volatile compounds in human exhalation

ＡｓａｙｏｆｓｏｍｅｖｏｌａｔｉｌｅｃｏｍｐｏｕｎｄｓｉｎｈｕｍａｎｅｘｈａｌａｔｉｏｎＱｉｎＴａｏ，ＸｕＸｉａｏｂａｉＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅ...     

Test for the effects of three surfactants on the penetration ability of the calcium chloride and water glass solutions in dust

１ＩｎｔｒｏｄｕｃｔｉｏｎＣａｌｃｉｕｍｃｈｌｏｒｉｄｅｉｓｏｆｔｅｎｕｓｅｄｉｎｔｈｅｆｉｅｌｄｏｆｓｏｉｌｓｔａｂｉｌｉｚａｔｉｏｎａｎｄｒａｉｓｉｎｇｄｕｓｔｃｏｎｔｒｏｌｂｅｃａｕｓｅｉｔｃａｎｒｅａｃｔｗｉｔｈｗａｔｅｒｇｌａｓ（Ｗｕ，１９...