Laboratory study of soil acidification and leaching of nutrients from a soil amended with various surface-incorporated acidifying agents

Granular S, finely-ground S, iron sulphate and aluminium sulphate were added at two rates to the surface (0–6 cm) of a soil and acidification and leaching of nutrients were measured over 12 months in a laboratory study. Iron and aluminium sulphate both rapidly lowered soil pH in the top 0–6 cm of the soil. There was little difference in soil pH after 3 and 12 months reaction of these two amendments. In contrast, for granular S and finely-ground S there were clear decreases in soil pH between 3 and 12 months reaction with the soil. Finely-ground S was oxidized in the soil faster than granular S and therefore had a more acidifying effect. The top 0–6 cm of the soil was acidified by all the agents used but the deeper soil was less affected. The only treatments which lowered the pH of the 12–18 cm layer below pH 6 were the high rates of iron and aluminium sulphate. Soil acidification resulted in a decrease in exchangeable Ca, Mg and K, an increase in exchangeable Al and a decrease in effective CEC in the acidified soil layers.At both levels of addition, total ionic strength of percolates from the soil followed the order: aluminium sulphate = iron sulphate > finely gound S > granular S > control and was higher at the higher rate of addition. The pH values of percolates followed the order: control > granular S > finely ground S > iron sulphate = aluminium sulphate and were lower at the higher rate of addition. For the amended soils there was a very close relationship between the pattern and total amounts of SO ₄ ^2- and Ca²⁺ leached.It was concluded that granular S is not an effective acidifying agent since it is oxidized very slowly in the soil and that acidfying agents should be incorporated to the depth that acidification is required.     

3-乙酰基-2-芳基-5-（2-碘苯基）-1，3，4-嗯二唑啉化合物的合成与表征

2-碘苯甲酰肼与八种芳醛反应得到相应的酰腙(1 a~1h),后与乙酸酐脱水环化合成3-乙酰基-2-芳基-5-(2-碘苯基)-1,3,4-噁二唑啉化合物(2 a~2h),通过元素分析、IR、1H NMR和MS对化合物2 a~2h的结构进行了表征。     

A novel sintering resistant and corrosion resistant Pt4ZrO2/C catalyst for high temperature PEMFCs

A novel Pt₄ZrO₂/C catalyst was prepared and compared with 20 wt.% Pt/C in terms of the sintering resistance and corrosion resistance. To evaluate their sintering resistance and corrosion resistance properties, an accelerated ageing test (AAT) was performed. The catalysts before and after AAT were characterized by cyclic voltammetry (CV), rotating disk electrode (RDE) and X-ray diffraction (XRD). After AAT, the dissolution rate of Pt and Zr in H₃PO₄ media (105 wt.%, 204 °C) was characterized by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The electrochemical area (ECA) changes of thin film electrodes based on Pt₄ZrO₂/C and Pt/C catalysts were also evaluated using continuous CV sweep technique. All the results showed that Pt₄ZrO₂/C has higher sintering resistance and corrosion resistance than Pt/C. ‘Anchor effect’ is proposed to explain the enhanced effect of ZrO₂ in Pt₄ZrO₂/C binary catalyst compared with Pt/C that contain platinum alone.     

Alarm pheromone system of leaf-footed bugLeptoglossus zonatus (Heteroptera: Coreidae)

The alarm pheromone system ofLeptoglossus zonatus (Dallas) adults was shown to be composed of hexyl acetate, hexanol, hexanal, and hexanoic acid. Single components tested in the field elicited dispersive behavior of over 70% of adults. 2-(E)-Hexenal, found in the secretion of nymphs, but not in the exudates of adults, was also active against adults. In addition, first-instar nymphs responded to the four components of the alarm pheromone of adults as well as to 2-(E)-hexenal, a component of their own alarm pheromone system. Adults and nymphs possess different alarm pheromone systems, which are not specific to their own life stage. That hemipteran alarm pheromone systems are not species-specific was supported by the fact that both adult and nymphL. zonatus responded to butanoic acid, an alarm pheromone of Alydidae, which was not found in this Coreidae species.     

俄罗斯对轮胎稳定剂的研究

俄罗斯轮胎工业研究院对俄轮胎稳定剂(稳定剂1)和P(稳定剂2)在俄轻、重型轮胎中的试用及与国外稳定剂产品Wingstay100、SPPD、6PPD、IPPD的配合使用进行了研究。结果表明,由于轻型轮胎的胎侧比重型胎胎侧薄1倍多,稳定剂损耗更快,因此在轻型胎胶中稳定剂1的用量一般比重型胎多50％-100％;稳定剂1与稳定剂2配合使用可提高侧胶耐磨损和抗破裂的稳定性;IPPD/SPPD/稳定剂2配合的稳定剂体系使胎侧胶耐热老化和抗疲劳的稳定性最好。     

Tween-60+Span-80/异戊醇/环己烷微乳液法制备纳米Fe3O4

采用W/O型Tween-60 Span-80/异戊醇/环己烷微乳液作为"微反应器"合成纳米磁性Fe3O4粒子。研究结果表明纳米Fe3O4粒子磁化率均随着反应温度、pH、铁离子的浓度比例ω(=[Fe2 ]/[Fe3 ])的增大先增大后减小;最优的制备条件为反应温度30℃、ω=1.2:2、pH=11。最优条件下制备的纳米Fe3O4粒子AFM图片表明所得纳米Fe3O4为均匀分散的球形微粒,平均粒径为70nm。     

Phase inversion and its effect on the properties of polyester polyurethane cationomers

Polyester polyurethane cationomers are prepared using polyester polyol of molecular weight 2000 as soft segments, N-methyl diethanolamine as chain extender, glycolic acid as quaternization agent, methyl ethyl ketone as solvent, and 4,4'-diphenylenemethylene diisocyanate (MDI) as diisocyanate. Properties of the films cast from solutions and emulsions are studied by infrared spectroscopy, dynamic mechanical analysis, thermogravimetric analysis, differential scanning calorimetry, and tensile-elongation testing. Ionization can cause phase separation and produces increased cohesion in the hard domains. The dispersion process can be divided into three stages involving a separation of hard segment aggregates due to adsorption of water on their surface, water entering into hard segment microionic lattics, and finally a rearrangement of agglomerates to form microspheres. The dispersion can disrupt the order in the hard domains and an increased phase separation.     

一种合成4-氰基联苯的方法

以联苯为原料,经傅克酰基化、氨解、脱水三步反应合成4-氰基联苯,不产生含氰废水。4-氰基联苯的总收率达到70.70%,HPLC含量达到98%以上。     

185nmUV降解水中4-CP、4-NP和RhB的研究

本文以对氯苯酚（4-cP）、对硝基苯酚（4-NP）和罗丹明B（RhB）为模型有机物（以4-CP和4-NP为小分子模型有机物，以RhB为大分子模型有机物），分别研究了185nmUV对水中这3种模型有机物的降解规律、性能和效果．研究结果表明，185nmUV直接对水中4-CP、4-NP和RhB有很好的降解效果．研究内容包括：185nmUV降解模型有机物的浓度、TOC（Totalorganic carbon）浓度、185nmUV降解模型有机物过程中溶液pH及电导率变化、以及降解模型有机物过程中产生的无机离子等几个方面．     

Suppression of the α → β-nickel hydroxide transformation in concentrated alkali: Role of dissolved cations

The presence of dissolved cations such as Al and Zn in alkaline electrolyte (6 M KOH) suppresses the -nickel hydroxide transformation. The uptake of Al (10 mol%) and Zn (30 mol%) exhibited by the active material likely stabilizes the -phase. Dissolved Al is deleterious to the performance of the nickel hydroxide electrode, whereas, dissolved Zn enhances the specific discharge capacity of nickel hydroxide by approximately 25% showing that the mode of metal uptake is different in the two cases.