Recent developments in the synthesis of 11β-aryl-estrone derivatives

An industrial synthesis of 11β-aryl-estrone derivatives is described, based on the 1,4-addition of the aryl side-chain, as a cuprate, on to a mixture of allylic 5(10) alpha and beta epoxides, followed by hydrolysis and subsequent aromatization.     

Strategic commitment to price to stimulate downstream innovation in a supply chain

It is generally in a firm’s interest for its supply chain partners to invest in innovations. To the extent that these innovations either reduce the partners’ variable costs or stimulate demand for the end product, they will tend to lead to higher levels of output for all of the firms in the chain. However, in response to the innovations of its partners, a firm may have an incentive to opportunistically increase its own prices. The possibility of such opportunistic behavior creates a hold-up problem that leads supply chain partners to underinvest in innovation. Clearly, this hold-up problem could be eliminated by a pre-commitment to price. However, by making an advance commitment to price, a firm sacrifices an important means of responding to demand uncertainty. In this paper we examine the trade-off that is faced when a firm’s channel partner has opportunities to invest in either cost reduction or quality improvement, i.e. demand enhancement. Should it commit to a price in order to encourage innovation, or should it remain flexible in order to respond to demand uncertainty. We discuss several simple wholesale pricing mechanisms with respect to this trade-off.     

Supercritical fluid chromatography of industrial paraffins and waxes

Summary The application of capillary SFC for SIMDIST investigations of paraffins and waxes is reported. Pressure, density and temperature of the mobile phase are optimized to obtain high chromatographic resolution of complex mixtures of industrial products. Isothermal linear pressure programming and asymptotic pressure and density programming are used in the range from 15 to 35 MPa in the isothermic mode above 100°C. SFC chromatograms of natural and synthetic paraffins, microcrystalline wax and candle wax are compared. The retention behaviour of paraffin mixtures and waxes has been investigated on methyl/phenyl and biphenyl capillary columns. The polarity of the stationary phases influences the absolute retention time more than it influences the chromatographic resolution.     

工业用水中总铁含量的快速测定

介绍了以菲咯嗪－醋酸钠－醋酸缓冲溶液为显色体系、用自制的铁含量比色测定仪快速测定工业用水中总铁含量的方法。总铁含量≤０５ｍｇ／Ｌ时，标准偏差≤００３ｍｇ／Ｌ；总铁含量＞０５ｍｇ／Ｌ时，相对标准偏差≤５％。单次测定时间（包括样品处理）为１０～１５ｍｉｎ。采用单色光源及微型流动比色池，由蠕动泵和电子线路实现自动进样，直接显示测定结果。     

Electron beam forming system for irradiation of large diameter cylindrical products

The report describes electron beam electromagnetic forming system, which is destined for irradiation of cylindrical long goods, specifically for PE tubes 160 mm diameter. System consists of electromagnet, power supply units, beam distributions control units, etc. for use at an electron accelerator at 5 MeV and 50 kW. The particular geometry of the magnet poles and their mutual arrangement are creating an irradiation field that allows the electrons to irradiate the surface of the product close to 90°.     

Evaluating the mobility of toxic metals in untreated industrial wastewater sludge using a BCR sequential extraction procedure and a leaching test

The distribution and speciation of toxic metals in industrial wastewater sludge (IWS) was investigated. In this work, the modified BCR three-stage sequential extraction procedure was applied to the fractionation of Cr Pb Ni, and Cd in untreated industrial wastewater sludge from industrial sites in Hyderabad (Pakistan). The extracts were analyzed using electrothermal atomic absorption spectrometry. The procedure was evaluated using a certified reference material for soil mixed with sewage sludge BCR 483. The results from the partitioning study indicate that more easily mobilized forms (acid exchangeable) of Cd were dominant. The oxidizable fraction was dominant for all four toxic metals. Metal recovery was good, with <4% difference between the total metal recovered through the extractant steps and the total metal determined after microwave digestion. Lixiviation tests (DIN 38414-S4) were used to evaluate the leaching of toxic species from IWS, and it was observed that levels of leachable toxic metals were low compared to the amount of metal extracted in the exchangeable fraction of the BCR protocol.     

Determination of volatile organic compounds in urban and industrial air from Tarragona by thermal desorption and gas chromatography-mass spectrometry

This study describes the optimisation of an analytical method to determine 54 volatile organic compounds (VOCs) in air samples by active collection on multisorbent tubes, followed by thermal desorption and gas chromatography-mass spectrometry. Two multisorbent beds, Carbograph 1/Carboxen 1000 and Tenax/Carbograph 1TD, were tested. The latter gave better results, mainly in terms of the peaks that appeared in blank chromatograms. Temperatures, times and flow desorption were optimised. Recoveries were higher than 98.9%, except methylene dichloride, for which the recovery was 74.9%. The method's detection limits were between 0.01 and 1.25 μg m⁻³ for a volume sample of 1200 ml, and the repeatability on analysis of 100 ng of VOCs, expressed as relative standard deviation for n = 3, was lower than 4% for all compounds. Urban and industrial air samples from the Tarragona region were analysed. Benzene, toluene, ethylbenzene and xylenes (BTEX) were found to be the most abundant VOCs in urban air. Total VOCs in urban samples ranged between 18 and 307 μg m⁻³. Methylene chloride, 1,4-dichlorobenzene, chloroform and styrene were the most abundant VOCs in industrial samples, and total VOCs ranged between 19 and 85 μg m⁻³.     

Nitroarene catalyzed oxidation with sodium percarbonate or sodium perborate as the terminal oxidant

A new catalytic oxidation method for the preparation of aromatic carboxylic acids from methyl aryl ketones is reported. The method is an alternative to the haloform reaction; it is benign and affords the desired product without production of any harmful side products. The catalytic cycle is based on the use of an electron-deficient nitroarene as catalyst with either of the two cheap and green oxidants sodium percarbonate or sodium perborate. The method gives a good yield (87%) and shows excellent selectivity when the model substrate (acetophenone) is oxidized. A series of benzoic acids of industrial interest were prepared by means of this method.     

The Wittig Reaction in Industrial Practice

The effects of a scientific discovery on industrial practice are illustrated with reference to the Wittig reaction. The aim of utilizing the Wittig reaction of linking terpenoid building blocks to give vitamin A and carotenoids on an industrial scale prompted extensive research and development work of a synthetic and chemical engineering nature. The importance of the Wittig reaction and its variants in the synthesis of active compounds and fine chemicals in industrial research is demonstrated in the present article.