Brominated flame retardants and dechlorane plus in the marine atmosphere from Southeast Asia toward Antarctica

The occurrence, distribution, and temperature dependence in the marine atmosphere of several alternative brominated flame retardants (BFRs), Dechlorane Plus (DP) and polybrominated diphenyl ethers (PBDEs) were investigated during a sampling cruise from the East Indian Archipelago toward the Indian Ocean and further to the Southern Ocean. Elevated concentrations were observed over the East Indian Archipelago, especially of the non-PBDE BFR hexabromobenzene (HBB) with concentrations up to 26 pg m(-3) which were found to be related to continental air masses from the East Indian Archipelago. Other alternative BFRs- pentabromotoulene (PBT), pentabromobenzene (PBBz), and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE)-were elevated, too, with concentrations up to 2.8, 4.3, and 2.3 pg m(-3), respectively. DP was detected from 0.26 to 11 pg m(-3) and bis-(2-ethylhexyl)-tetrabromophthalate (TBPH) ranged from not detected (nd) to 2.8 pg m(-3), respectively. PBDEs ranged from nd to 6.6 pg m(-3) (Σ(10)PBDEs) with the highest individual concentrations for BDE-209. The approach of Clausius-Clapeyron (CC) plots indicates that HBB is dominated by long-range atmospheric transport at lower temperatures over the Indian and Southern Ocean, while volatilization processes and additional atmospheric emissions dominate at higher temperatures. In contrast, BDE-28 and -47 are dominated by long-range transport without fresh emissions over the entire cruise transect and temperature range, indicating limited fresh emissions of the meanwhile classic PBDEs.     

Material surfaces for electron-optical equipment

Electron-beam inspection systems for VLSICs and electron-beam pattern generation require exact positioning of the electron beam on the specimen. In this connection the question arises as to what properties the walls and diaphragms in the ambience of the path of the electron beam are required to have with respect to material, surface layers and cleanness in order to exclude their collecting electric charges that will undesirably influence the electron beam. Experimental investigations of this problem by means of electron-shadow projection show that the conductivity of a material should not be the sole criterion for its choice, but that its behavior under exposure to backscattered electrons and secondary electron emission must also be taken into account. Graphite of poor conductivity was found to be particularly favorable. Electroplated surfaces are often less favorable than untreated surfaces. Magnetic materials always exhibit minor defects. For cleaning, a carefully controlled ultrasonic technique using conventional cleaning agents is necessary and sufficient.     

Brominated flame retardants in seawater and atmosphere of the Atlantic and the Southern Ocean

Seawater and air samples were collected aboard the FS Polarstern during the cruises ANT-XXV/1 + 2 in the Atlantic and Southern Ocean in 2008. The particulate and dissolved phase in water and particulate and gaseous phase in air were analyzed separately for nine polybrominated diphenyl ethers (PBDEs) and six non-PBDE brominated flame retardants (BFRs). Air concentrations of 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and hexabromobenzene (HBB) in the gaseous and particulate phase (median = 0.56 pg m(-3) for DPTE and 0.92 pg m(-3) for HBB) were comparable to ∑(9)PBDEs (1.0 pg m(-3)). Pentabromotoluene (PBT) was detectable in ～30% of the gaseous phase samples, whereas concentration of 2,4,6-tribromophenyl allylether (ATE), hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) and 2-ethyl-1-hexyl 2,3,4,5-tetrabromobenzoate (EHTBB) were below their method detection limits. DPTE, and PBDEs were also found in seawater at low pg per liter levels. Elevated seawater concentrations of PBDEs and DPTE were measured in the English Channel and close to South African coast. Concentrations of DPTE, BDE-47, and BDE-99 in the atmosphere generally decreased from Europe toward the Southern Ocean, whereas no latitudinal trend was observed in seawater. Air-water exchange gradients suggested net deposition dominates for all selected substances. The medians of net deposition fluxes for the air-water gas exchange were 83, 21, 69, 20, and 781 pg m(-2) day(-1) for BDE-47, BDE-100, BDE-99, DPTE, and HBB, whereas medians of dry deposition fluxes were 2.0, 0.3, 1.2, 1.0, and 0.5 pg m(-2) day(-1) for BDE-47, BDE-100, BDE-99, DPTE, and HBB. Overall, these results highlight the important role of the long-range atmospheric transport of PBDE and non-PBDE BFRs to remote regions.     

Strength behaviour of flawed pipes under internal pressure and external bending moment: Comparison between experiment and calculation

Experimentally determined failure curves for pipes weakened by surface longitudinal or circumferential defects, were compared with results calculated with the aid of engineering approximation methods. Considering the scatter bands of the mechanical properties and the geometrical dimensions, then by use of the engineering approximation methods, one can make only rough estimates of the load bearing behaviour.     

An empirical bayes strategy for analysing manufacturing data in real time

This paper discusses and develops a real-time strategy to monitor manufacturing process control data. The strategy presented in this paper is designed to intercept, analyse and monitor data as measurements are generated from a high-volume information-intensive manufacturing process. Empirical Bayes theory is used to develop a method to monitor and analyse continuous type measurements generated by a manufacturing process in real time. Several specific techniques will be proposed for detecting manufacturing process problems and examples of applying these techniques will be shown.     

Analysis of the failure behaviour of longitudinally flawed pipes and vessels

A post-calculation by means of four engineering approaches, based on toughness, yield stress, plastic instability and ligament stress criteria, was made of the failure pressure on 134 pipes and vessels. The calculation was assessed by comparing the calculated with the experimentally obtained results. A statistical-based evaluation was made, since the results from the calculation and the experiment are affected by natural scattering of characteristic values, such as material properties and geometrical dimensions, among others. It was possible to find for each equation an individual weighting factor, which helped to improve considerably the approximation of the calculation to the experimentally determined failure pressure.     

Fluorescent whitening agents: Acute fish toxicity and accumulation studies

Four fluorescent whitening agents (FWA), three of which are currently marketed in the United States for use as ingredients in household laundry detergents, were tested to determine their acute toxicity to the bluegill (Lepomis macrochirus), as well as their potential for significant accumulation in the flesh of the bluegill and channel catfish (Ictalurus punctatus), two species of fish common to U.S. waters. Results of the acute toxicity bioassays showed that no acutely toxic effects on fish, caused by these materials, would be expected at concentrations well above their projected environmental levels. Rates of accumulation and maximum levels accumulated were evaluated in the laboratory for a period of 90–105 days, followed by an examination of the rate of elimination of these materials from the fish over a 28-day period. Under these conditions, neither species accumulated any of three anionic fluorescent whitening agents (sulfonated stilbene derivatives) when exposed to nominal concentrations of 0.125, 1.25, or 12.5 μg 1⁻¹ in water. A nonionic FWA not currently used in the U.S. detergent formulations was significantly accumulated at the two highest concentrations tested. The nonionic FWA accumulated was rapidly eliminated by fish upon their transfer to water devoid of this chemical. Elimination of FWA was essentially complete by 14 days. No significant accumulation by fish was detected with any FWA when exposure was conducted at levels approximating projected environmental concentrations. Details of the acute toxicity tests, and the patterns of accumulation and elimination seen in this study, as well as their significance, are discussed.