含氮化合物废气选择性催化氧化技术研究进展

通过对当前含氮化合物废气治理技术的对比分析,总结选择性催化氧化的相关技术优势。根据对含氮化合物的种类及来源分析,介绍氨气、腈类、胺类及其他含氮化合物的催化净化技术。重点总结催化剂的种类、研发进展和在实际使用中可能遇到的问题,同时展望含氮化合物废气选择性催化氧化技术的研发方向。     

Butyltin Species and Inorganic Tin in Water and Sediment of the Detroit and St. Clair Rivers

Water and sediment samples from 29 locations in the Detroit and St. Clair rivers were analyzed for the highly toxic tri-n-butyltin (Bu₃Sn⁺) species and for the less toxic di-n-butyltin (Bu₂Sn²⁺) and n-butyltin (BuSn³⁺) species and inorganic tin. In general, locations sampled in the St. Clair River were less contaminated with butyltin species than those in the Detroit River. Inorganic tin and BuSn³⁺ were detected in over 90% of all subsurface water samples, while Bu₂Sn²⁺ and Bu₃Sn⁺ were detected in 45 and 28% of the same samples, respectively. The highest concentration ofBu₃Sn⁺ in subsurface water, 5.9 × 10^?10 mol Sn/L, was at the mouth of the Ecorse River, a tributary of the Detroit River. The three butyltin species and inorganic tin were also detected in 23–46% of all sediment samples. The highest concentrations of Bu₃Sn⁺ in sediment were found close to the mouths of the River Rouge, another tributary of the Detroit River, and the Ecorse River, and were 6.2 × I0^–7 and 1.7 × I0^–7 mol Sn/kg dry weight, respectively, for the top 2 cm of sediment.     

Forecasting Capillary Characteristics for Aluminum Nitride Ceramic ― Liquid Metal Systems

A test has been devised that allows one to determine the work of adhesion and wettability in a system composed of aluminum nitride ceramics with a liquid metal without the need for experimental examination. A correlation is examined between the work of adhesion on the one hand and that criteria or others on the other that have been proposed by various researchers. Forecasts are made for the work of adhesion and wetting angle for a series of metals that have not been examined previously. An experimental check has been made on the forecast adhesion activity for some elements.     

Oscillating Cup Viscosity Measurements of Aluminum Alloys: A201, A319 and A356

An oscillating cup viscometer was developed to measure the absolute viscosities of molten metals. Previous experiments established the capability of the apparatus to characterize the viscosities of molten nickel-based superalloys. However, modifications to the instrument and its theoretical analysis were required for reliable measurements on molten aluminum alloys, presumably due to their lower densities and lower viscosities. The theoretical literature for the fluid flow inside an oscillating cup is reviewed, and a working equation without any correction factor is developed for the improved viscometer. Some design parameters of the viscometer that directly affect the accuracy of viscosity estimation by using the working equation are discussed. A special vertical furnace was adopted to uniformly heat a longer cylindrical sample (10 mm inner diameter and 120 mm length) with a temperature difference of less than 2°C over the sample length. The measuring procedure was also improved to get more accurate motion parameters. It is estimated that the working equation and improved instrument provide an uncertainty of less than 4%. In addition, applications and experimental data are presented for pure aluminum and three aluminum alloys: A201, A319, and A356.     

Preliminary Assessment of Contaminants in Soft Sediments of the Detroit River

Soft sediments from the Detroit River were analyzed for the USEPA priority pollutants to generally characterize contaminant distribution. Forty-three were detected. Highest heavy metal concentrations were found in the Trenton Channel and immediately downstream of Grosse Ile. They ranged from an area mean (N = 2) of 0.19 mg/kg mercury to 338.7 mg/kg zinc (dry weight). Polynuclear aromatic hydrocarbons ranged from 0.1 mg/kg to 38.8 mg/kg (mean, N = 2) with the highest levels near Grosse Ile. PCBs ranged from 0.015 mg/kg to 1.7 mg/kg (mean, N = 2). Organochlorine pesticides were not detected except for a trace of heptachlor in one sample. Sediment contamination in the Detroit River is widespread with higher concentrations on the U.S. side downstream of the Rouge River and in the Trenton Channel. The significance of these in-place pollutants to biota and as a source to Lake Erie is still unknown.     

Baseline assessment of metals and hydrocarbons in the sediments of Lake Mulwala, Australia

An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg⁻¹) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons.     

难熔金属与硬质材料进展─—从第十三届国际普兰西会议看发展动向（Ⅰ）

根据第十三届国际普兰西会议获得的信息，对国际上难熔金属、硬质合金、硬质材料和涂层技术等方面近几年来的研究和发展动态进行了综合评述。最后，提出了几点自己的看法。     

Effect of Iron on the Color of Barley and Other Cereal Porridges

ABSTRACT: Iron added as ferrous sulfate at 500 mg*kg⁻¹ to rice, oats, whole grain wheat, or proanthocyanidin-free barley porridge caused significant changes in the Hunter "L", "a", and "b" values but the visual appearance of these porridges remained satisfactory. Porridge made with normal barley flour fortified with 500 mg*kg⁻¹ of iron developed an unappealing gray color with ferrous sulfate, ferrous fumarate, or electrolytic iron, 3 salts differing in solubility. At 100 and 250 mg*kg⁻¹ of iron, the discoloration of normal barley porridge was less pronounced, but still objectionable. When fortified with 50 mg*kg⁻¹ of iron, normal barley porridge had a slight color change but was not noticeably gray. Thus barley-containing foods can be fortified with a soluble iron compound at the level of iron used in enriched flour and similar cereal-grain foods for the general population without developing an unattractive color.     

发泡金属的开发、性质及应用(Ⅰ)──发泡金属的制备方法

系统地综述了发泡金属的生产方法，包括铸造法、粉末冶金法、烧结法、沉积法和高压浸透法等。介绍了各种方法的特点及适用范围，指出了它们的优缺点及相应的改进措施，并对今后的发展方向提出了建议。     

Isotherm analyses for single component and multi-component metal sorption onto lignite

The adsorption of the three metal ions, copper, cadmium and zinc in single component and multi-component mixtures in aqueous solutions by lignite is reported. A comparison is made between the single component saturation uptake and the multi-component uptakes. The isotherms indicate a competitive uptake with copper being preferentially absorbed by the lignite in multi-component solutions. The isotherms are plotted to obtain the Langmuir constants, the Freundlich constants and the Redlich–Peterson constants. Lignite is shown to possess an affinity for the metal ions which make its use as an adsorbent a possible alternative to the use of more expensive activated carbons.