[en] A novel hot-wire chemical vapor deposition (HW-CVD) geometry was employed to study the deposition of Teflon-like films from hexafluoropropylene oxide (HFPO). In this configuration hot wires were replaced by thin ribbons, and under proper operating conditions the complex HW-CVD geometry is simplified to a one-dimensional system. The kinetics of both HFPO decomposition and Teflon deposition were measured as a function of operating conditions. A hybrid 2-D CFD/1-D stagnation flow model was used to interpret the results. At relatively low ribbon temperatures good agreement between model and experiment was observed. Deviations observed at higher ribbon temperatures were attributed to gas-phase polymerization of CF₂ moieties, and participation of these oligomers in the deposition process

[en] Apparatus for filtering and removing heat from pressurized gases, particularly gases from a nuclear reactor accident, comprising: an impervious enclosure; a filter having a porous filter bed, the top of the porous filter bed defining a first stage within the enclosure, a second stage extending therefrom to the water level within the enclosure and of greater height than the first stage; the cross-sectional area of the porous filter bed defining a central region and a boundary region surrounding the central region; a distributor for receiving hot pressurized gases and distributing same toward the porous filter bed; and means for permitting water to flow from the boundary region in the first stage, laterally inwardly to within the space between the porous filter bed and the base of the enclosure for mixing with the gases and producing a mixed two-phase flow through the first and second stages. (author)

[en] Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy for the treatment of uveal melanoma resulted in fewer abnormal maculas, lower central macular thickness on OCT, and a trend toward better final visual acuity in comparison with matched control patients who underwent brachytherapy alone

[en] The oilfield specialty chemical market has undergone many changes over the past 10 years. Looking back to 1980-1981, the oilfield chemical market was robust as oilfield activity was peaking at 4,500 rigs in the U.S. and 5,800 rigs worldwide. At that time, a fever-pitched industry sought new specialty chemicals for improved drilling, completion and workover, cementing, stimulation, production, and particularly enhanced oil recovery (EOR) techniques. After all, crude oil was reaching $40/barrel and the outlook showed $100/barrel by the end of the decade. Complicating matters, however, was the fact that while higher oil and gas prices were spurring oilfield activity they were also pushing the world into a recession. And, as commodity chemical usage was declining rapidly, many chemical companies, seeking relief from the cyclicality of commodity products, ventured into the oilfield specialty chemical segment. (Author)

[en] The kinetics and thermodynamics of octadecyltrichlorosilane (OTS) self-assembled monolayers (SAMs) on vapor deposited alumina were quantified. Ozone cleaning serves to create well-defined hydrophilic surfaces for OTS attachment, and the use of heptane as a solvent enables the formation of high quality SAMs under ambient conditions. The kinetics was characterized as a function of OTS concentration using contact angle goniometry, ellipsometry and Fourier transform infrared (FTIR) spectroscopy. The kinetics of SAM formation and the saturation contact angle (∼100^o) on alumina are comparable to what has been observed for OTS on silicon. The free energy of adsorption with ΔG_ads values ranged from −7.5 to −5.4 kcal/mol, and the SAMs were stable up to 230 ^oC. The critical surface tension of the OTS monolayer was found to be 21.4 dyne/cm.

[en] This paper describes a methodology which could be applicable to establish a country report. In the framework of nuclear non proliferation appraisal and IAEA safeguards implementation, it is important to be able to assess the potential existence of undeclared nuclear materials and activities as undeclared facilities in the country under review. In our views a country report should aim at providing detailed information on nuclear related activities for each country examined taken 'as a whole' such as nuclear development, scientific and technical capabilities, etc. In order to study a specific country, we need to know if there is already an operating nuclear civil programme or not. In the first case, we have to check carefully if it could divert nuclear material, if there are misused declared facilities or if they operate undeclared facilities and conduct undeclared activities aiming at manufacturing nuclear weapon. In the second case, we should pay attention to the development of a nuclear civil project. A country report is based on a wide span of information (most of the time coming from open sources but sometimes coming also from confidential or private ones). Therefore, it is important to carefully check the nature and the credibility (reliability?) of these sources through cross-check examination. Eventually, it is necessary to merge information from different sources and apply an expertise filter. We have at our disposal a lot of performing tools to help us to assess, understand and evaluate the situation (cartography, imagery, bibliometry, etc.). These tools allow us to offer the best conclusions as far as possible. The paper is followed by the slides of the presentation. (author)

[en] Plasma-enhanced chemical vapor deposition has been used to form electrochromic tungsten oxide thin films from gas mixtures of WF₆, O₂, and H₂. The chemistry of this system was investigated using optical emission spectroscopy. The plasma composition and deposition rate were examined as a function of operating conditions. Growth rates were maximized when the atomic fluorine density was attenuated and the atomic oxygen density was saturated. With the exception of hydrogen scavenging of fluorine radicals, the major reaction pathway was simply dissociation, as the densities of the atomic species were proportional to the initial reagent composition. An apparatus was built to evaluate electrochemical performance in direct registry with optical transmission. This characterization technique was used to demonstrate that ion bombardment has a dramatic impact on electrochromic performance. Ion bombardment was found to increase film density, as inferred from measurements of the refractive index. Efficient hydrogen intercalation was observed only in those films whose refractive index at 400 nm were less than 2.1. Finally, it was shown that a tungsten oxide thickness of ∼600 nm was optimal with respect to contrast ratio

[en] Highlights: • Detailed energy data can be developed from U.S. greenhouse gas reporting. • Nearly all heat demand at temperatures below 100 °C occur in the Midwest. • Medium- and high-temperature demands are more evenly distributed. • The technical potential of alternative heat supplies is 30% of heat demand. -- Abstract: Industry is frequently highlighted as the world’s largest energy-using end-use sector. More specifically, the demand for heat drives much of the demand for energy and fossil fuels in the industrial sector. We conduct a top-down analysis to characterize historical energy and fossil fuel use in 14 top-GHG-emitting industries in the United States, their heat demand requirements, and the potential to substitute heat from geothermal, solar thermal (including concentrating technologies), and small modular nuclear reactors to meet these needs while reducing fossil-fuel use and greenhouse gas (GHG) emissions. We base this analysis on publicly-available facility-level GHG emissions and fuel-combustion data, in addition to assumed requirements for process temperature, to demonstrate the potential value to industry energy analysts of the U.S. Environmental Protection Agency’s Greenhouse Gas Reporting Program data. We estimate on a county level that the adoption of these alternative heat sources could have reduced 2015 fossil-fuel use by approximately 31% and combustion GHG emissions by approximately 24%. The most extensive substitution opportunities are in the ethyl alcohol manufacturing and wet corn-milling industries; petroleum refining represents the largest absolute emissions mitigation potential. This initial top-down analysis of substitution potential does not consider more detailed technical factors, including resource availability that will influence the actual deployment of alternative energy technologies. The analysis also does not consider the economic or market factors, including the expected cost to build and operate these generators. We do assume process byproducts that are extensively used for combustion fuels would not be good candidates for substitution for alternative energy generators. Based on these caveats, our analysis could be considered a top-range estimate for this mix of heat generators and industry heat demands. Any subsequent analysis of these alternate energy sources should increase the level of technical, economic, and policy detail.

[en] Self-limiting deposition of aluminum oxide (Al₂O₃) thin films was accomplished by pulsed plasma-enhanced chemical vapor deposition using a continuous delivery of trimethyl aluminum (TMA) and O₂. Film characterization included spectroscopic ellipsometry and Fourier transform infrared (FTIR) spectroscopy. Deposition rates scaled with TMA exposure and could be controlled over a large range of 1-20 A/pulse. For fixed conditions, digital control over film thickness is demonstrated. Deposition rates initially decreased with substrate temperature before becoming constant for T_s>100 deg. C. Higher growth rates at low temperature are attributed to the thermal reaction between H₂O, produced during the plasma on step, with TMA during the plasma off step. Gas-phase analysis confirms the coexistence of these species, and their degree of overlap is a strong function of the chamber wall temperature. With both the substrate and chamber wall temperature elevated, impurities related to carbon and hydroxyl groups are attenuated below the detection limit of FTIR

[en] A first report proposes an overview of hydrogeological and chemical knowledge of the Aquitaine basin (geological history, Eocene aquifers, Infra-Molasse sand aquifers, Paleocene aquifers), a determination of physical-chemical well-logging of underground waters (methods, application, and interpretation), a study of underground water chemistry (protocol, analysis, results and interpretation of sampling campaign in May 2006), a report of an isotopic approach to underground waters during this campaign of May 2006 and the presentation of another sampling campaign performed in October 2006. The last chapter presents communication actions (web site, scientific valorization). The second report presents the objectives and means of the Carismeau project, recalls various aspects concerning the definition, measurements and operation of isotopes, presents isotopic tools, and report their application to the management of water resources. Synthesis sheets are proposed, as well as abstracts of contributions to conferences and submitted articles.