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Decomposition of highly vibrationally excited CDCl3 was studied in the time domain by measuring laser-induced fluorescence from one of the decomposition products CCl2 or by observing luminescence from CCl2 radical fragments produced in the A(1B1) state following IR excitation. It is shown that highly vibrationally excited CDCl3 can be made via two different routes: i\mple optical absorption of an incident 13CO2 laser pulse or through collision-moderated energy pooling coupled with photon absorption. Higher fluence measurements are consistent with the former and support previous claims that the infrared multiphoton decomposition probability for CDCl3 is pressure independent. At a lower fluence the vibrational up-pumping mechanism apparently relies heavily upon collisions, which supports other claims that the decomposition probability is pressure dependent. The results of the present work reconcile these previous disparate claims. Furthermore, there is an indication that the vibrational energy transferred during a collision could be much larger than collision-induced dipole selection rules would allow. In some of the experiments, electronically excited CCl2 fragments are created but only through post-laser-pulse collisions that appear to involve exchanges of very large amounts of vibrational energy. By contrast, no electronically excited CCl2 is produced following excitation with the CO2 laser alone. The experiments also corroborate an earlier prediction that the extent of reaction is governed by adiabatic expansion of the centrally heated zone, even at pressures as low as 0.66 kPa, rather than by diffusion, as is commonly believed. [ABSTRACT FROM AUTHOR]

The most important radioisotope for nuclear medicine is Tc. After the supply crisis of Mo starting in 2008, the availability of Tc became a worldwide concern. Alternative methods for producing the medical imaging isotope Tc are actively being developed around the world. The reaction Mo( p, 2 n)Tc provides a direct route that can be incorporated into routine production in nuclear medicine centers that possess medical cyclotrons for production of other isotopes, such as those used for Positron Emission Tomography. This paper describes a new approach for manufacturing targets for the ( p, 2n) nuclear reaction on Mo and the foundation for the subsequent commercial separation and purification of the Tc produced. Two designs of targets are presented. The targets used to produce Tc are subject to a number of operational constraints.They must withstand the temperatures generated by the irradiation, accommodate temperature gradients from cooling system of the target, must be resilient and must be easily post-processed to separate the Tc. After irradiation, the separation of Tc from Mo was carried out using an innovative two-step approach. The process described in this paper can be automated with modules that easily fit in standard production hot cells found in nuclear medicine facilities. [ABSTRACT FROM AUTHOR]

simple, sensitive, and specific analytical method has been developed for the quantitative determination of 15 reducing carbohydrates in the soil solution of crop rhizosphere. Reducing carbohydrates were derivatized with 1-phenyl-3-methyl-5-pyrazolone, separated by reversed-phase high-performance liquid chromatography and detected by electrospray ionization tandem mass spectrometry. Lower limits of quantitation of 2 ng/mL were achieved for all carbohydrates. Quantitation was performed using peak area ratios (analyte/internal standard) and a calibration curve spiked in water with glucose-d as the internal standard. Calibration curves showed excellent linearity over the range 2-100 ng/mL (10-1,000 ng/mL for glucose). The method has been tested with quality control samples spiked in water and soil solution samples obtained from the rhizosphere of wheat and canola and has been found to provide accurate and precise results. [ABSTRACT FROM AUTHOR]

Injection of CO2 into geological structures is a key technology for sequestering CO2 emissions captured from the combustion of fossil fuels. Current projects inject volumes on the order of megatonnes per year. However, injection volumes must be increased by several orders of magnitude for material reductions in ambient concentrations. A number of questions surrounding safety and security of injection have been raised about the large scale deployment of geological CO2 sequestration. They are site specific and require an effective monitoring strategy to mitigate risks of concern to stakeholders. This paper presents a model-based framework for monitoring design that can provide a quantitative understanding of the trade-offs between operational decisions of cost footprint size, and uncertainty in monitoring strategies. Potential risks and challenges of monitoring large scale CO2 injection are discussed, and research areas needed to address uncertainties are identified. Lack of clear guidance surrounding monitoring has contributed to hampering the development of policies to promote the deployment of large scale sequestration projects. Modeling provides an understanding of site specific processes and allows insights into the complexity of these systems, facilitating the calibration of an appropriate plan to manage risk. An integrated policy for risk-based monitoring design, prior to large scale deployment of sequestration will ensure safe and secure storage through an understanding of the real risks associated with large scale injection. [ABSTRACT FROM AUTHOR]

The environment has emerged as an important determinant of the performance of the modern chemical industry. This paper reviews approaches for incorporating environmental issues into the design of new processes and manufacturing facilities. The organizational framework is the design process itself, which includes framing the problem and generating, analyzing, and evaluating alternatives. A historical perspective on the chemical process synthesis problem illustrates how both performance objectives and the context of the design have evolved to the point where environmental issues must be considered throughout the production chain. In particular, the review illustrates the need to view environmental issues as part of the design objectives rather than as constraints on operations. A concluding section identifies gaps in the literature and opportunities for additional research. [ABSTRACT FROM AUTHOR]

As the valve seat hardfacing materials in boiler feed water service of coal power plants, the corrosion behavior of Stellite 6 alloy and 17-4PH stainless steel in amine solutions is studied using electrochemical test methods. Morpholine, cyclohexylamine, and sodium hydroxide (NaOH) solution with pH 9.5 are selected to be the corrosive media. The first solution is a typical amine medium, the second one is selected to examine if different amine media with the same pH can result in any change in the corrosion behavior of these materials. Sodium hydroxide is chosen to offset the effect of pH change. Polarization test is performed on Stellite 6 alloy and 17-4PH stainless steel under the low potential varying from –0.4 VSCE to 1.2 VSCE and is also conducted under a constant high potential (4 VSCE) in order to fail the sample surfaces. The polarization curves 17-4PH stainless steel from the low potential tests show an apparent passivation region indicating a protective oxide film formed on the sample surface, but Stellite 6 alloy only exhibits a tendency to passivate. The Stellite 6 alloy and 17-4PH stainless steel samples after the failure tests under the high potential (4 VSC) are analyzed using SEM/EDX. It is shown that the former is severely corroded in all the solutions while the latter is only corroded in morpholine solution and it is very corrosion-resistant in sodium hydroxide solution. The corrosion mechanisms of Stellite 6 alloy and 17-4PH stainless steel in amine solutions are discussed with assistance of the Pourbaix diagrams. [ABSTRACT FROM AUTHOR]

Florence Nightingale and subsequent nurse scholars have written about the impact of the environment on human health. Nightingale described, and staked out, the nurse's role in optimizing environments for healing. Since Nightingale's time numerous scholars have documented that environmental conditions play a major role in the health of individuals and populations. As nurses become more informed about the environment as a determinant of human health, they will be able to advocate more effectively for environmental conditions that promote health. This article provides both theoretical and practical perspectives to integrate environmental concerns into nursing practice. It recommends specific actions nurses can undertake to improve the environment within the health care setting. In particular the article provides a historical review of an environmental focus in nursing, discusses ways to manage both upstream waste and downstream waste (solid, biohazard, and hazardous chemical wastes) so as to decrease environmental pollution, and recommends specific nursing actions to promote a healthy environment within our health care agencies. [ABSTRACT FROM AUTHOR]

Background: Infectious disease has a significant impact on livestock production. Availability of alternatives to antibiotics to prevent and treat disease is required to reduce reliance on antibiotics while not impacting animal welfare. Innate immune stimulants, such as mycobacterium cell wall fractions (MCWF), are used as alternatives to antibiotics for the treatment and prevention of infectious disease in a number of species including cattle, horses and dogs. This study aimed to evaluate the safety of Amplimune®, an MCWF‐based immune stimulant, for weaner Angus cattle. Methods: On day −1 and 0, sixty mixed‐sex Angus weaner cattle were transported for 6 h before being inducted and housed in a large single pen, simulating feedlot induction conditions. The cattle were assigned to one of six treatment groups (n = 10 per group): 2 mL Amplimune intramuscularly (2IM); 2 mL Amplimune subcutaneously (2SC); 5 mL Amplimune intramuscularly (5IM); 5 mL Amplimune subcutaneously (5SC); 5 mL saline intramuscularly (SalIM) and 5 mL saline subcutaneously (SalSC) on day 0 following transportation. Body temperature, body weight, concentrations of circulating pro‐inflammatory cytokines (TNFα, IL‐1β, IL‐6 and IL‐12) and haematology parameters were measured at various times up to 96 h post‐treatment. Results: No adverse effects from Amplimune treatment were observed. Amplimune induced an increase in circulating cytokine TNFα concentrations, total white blood cell count and lymphocyte counts indicative of activation of the innate immune system without causing an excessive inflammatory response. Conclusions: Results confirm that Amplimune can be safely administered to beef cattle at the dose rates and via the routes of administration investigated here. [ABSTRACT FROM AUTHOR]

Abstract: The effect of concrete pore solution composition on the protective properties of the oxide films that form on black reinforcing steel has been experimentally investigated using anodic polarization and electrochemical impedance spectroscopy (EIS). The tests were conducted on oxide films grown in saturated calcium hydroxide solutions that included different representative amounts of NaOH, KOH, and Ca(SO4), which are compounds that are commonly observed in most ordinary portland cement concrete types. The results of both anodic polarization and EIS tests show that pore solution composition has an effect on the protective properties of the passive oxide films and, in particular, sulfate ions have been shown to have a negative influence on the film quality. [Copyright &y& Elsevier]

A probe has been developed to determine the solubility of hydrogen in metals. The method is based on mass balance and high-pressure hydrogen produced in situ partitioning between a zirconium probe and the metal. As an example, the solubility of hydrogen in copper, SH in Cu, has been determined between 350 and 450 °C: S H\,in\,Cu = (1000 ± 200) exp - 43000 ± 1300 RT [mol H 2 / m 3 MPa ]. This solubility agrees with permeation and diffusivity measurements spanning 10 and 6 orders of magnitude, respectively. [ABSTRACT FROM AUTHOR]