REACTOR-MEMBRANE PERMEATOR CASCADE FOR ENHANCED PRODUCTION AND RECOVERY OF H2 AND CO2 FROM THE CATALYTIC METHANE-STEAM REFORMING REACTION

The catalytic reforming of methane by steam is an important industrial process that produces H₂, CO and CO₂, thus chemically transforming natural gas, coal gas and light hydrocarbon feedstocks to synthesis gas or hydrogen fuel. Methane-steam reforming may consist of a number of reactions depending on the reforming catalyst, operating conditions and feedstock composition, The typical industrially desirable reactions are the reverse of methanation (CH₄ + H₂O = CO + 3H₂) and the water-gas shift (CO + H₂O = CO₂ + H₂). Both reactions are equilibrium limited and the composition of the mixture that exits the reformer is in accordance with the one calculated thermodynarmically. Removal of reaction products at the reactor exit by means of selective membrane permeation can offer improved CH₄ conversions and CO₂ and H₂ yields, assuming the subsequent utilization of the reject streams by a second methane-steam reformer. We numerically investigated the feasibility of a system of two tubular methane-steam reformers, in series with an intermediate permselective polyimide membrane permeator, as means of improving the overall CH₄ conversion and the H₂, CO₂ yields over conventional methane-steam reforming equilibrium reaction-separation schemes that are currently in industrial practice. The unique feature of the permselective polyimide separator is the simultaneous removal of H₂ and CO₂ versus CH₄ and CO from the reformed streams. The utilized 6FDA-3,3', 5,5'-TMB aromatic polyimide was reportedly characterized [10] and found to exhibit superior permselective properties compared with other polyimides of the same or different dianhydride sequence. Conversion and yield of the designed reactor-membrane permeator reforming system can be maximized by optimizing the permselective properties of the membrane material and the design variables of the reactors and the permeator. Product recovery and purity in the permeate stream need to be compromised to overall enhance methane conversion and product yield. The operating variables that were varied to investigate their effect on the magnitude of conversion and yield included the inlet pressure of the first reformer, the temperature of both reformers, and the permeator dimensionless Pe' number (variation of the first two variables results to a drastic change in the composition of the reformed stream that enters into the permeator). The numerical results show that the new reformer-membrane permeator cascade process can be more effective (it can offer increased CH₄ conversions and H₂, CO₂ yields) than conventional equilibrium methane-steam reforming reaction-separation processes currently in practice.     

Comparing Public Perceptions of Alternative Water Sources for Potable Use: The Case of Rainwater,Stormwater, Desalinated Water,and Recycled Water

This research investigated how people’s perceptions of alternative water sources compare with their perceptions of other technologies, and identified significant predictors of comfort with different alternative water sources. We drew on data from four questionnaire survey studies with a total sample of more than 1200 Australian participants. Relative levels of comfort with the alternative water sources was consistent across the four studies: comfort was always highest for drinking rainwater and lowest for drinking recycled water, with comfort with drinking treated stormwater and desalinated water sitting between these two. Although comfort with drinking recycled water was always lowest of the four alternative water sources, participants were significantly more comfortable with drinking recycled water than they were with nuclear energy, or with using genetically modified plants and animals for food. In general, demographic variables were less important predictors of comfort with alternative water sources than were psychological variables; only age and gender emerged as relatively consistent predictors for recycled water, stormwater, and desalinated water, with older participants and males more comfortable with drinking these water sources. Of the psychological variables, participants’ comfort with technology in general, trust in science and trust in government emerged consistently as significant positive predictors of comfort with drinking recycled water, stormwater, and desalinated water.

     

Accommodation of impurities in α-Al2O3, α-Cr2O3 and α-Fe2O3

Atomic scale computer simulation was used to predict the mechanisms and energies associated with the accommodation of aliovalent and isovalent dopants in three host oxides with the corundum structure. Here we consider a much more extensive range of dopant ions than has previously been the case. This enables a rigorous comparison of calculated mechanism energetics. From this we predict that divalent ions are charge compensated by oxygen vacancies and tetravalent ions by cation vacancies over the full range of dopant radii. When defect associations are included in the model these conclusions remain valid. At equilibrium, defects resulting from extrinsic dopant solution dominate intrinsic processes, except for the largest dopant cations. Solution reaction energies increase markedly with increasing dopant radius. The behaviour of cluster binding energies is more complex.     

Salmonella Enteritidis in shell eggs: Current issues and prospects for control

Foodborne illness caused by Salmonella spp. is a worldwide problem. In the United States Salmonella Enteritidis is the second most commonly isolated serotype from human illness, and is known to be strongly associated with shell eggs and egg containing products. Eggs can become contaminated internally either by penetration through the shell or directly during formation in the reproductive tract. This review begins with a brief account of the physiology of egg production and the various physical and chemical barriers the egg possesses to prevent bacterial contamination. Factors involved in vertical and horizontal transmission of S. Enteritidis are examined, as well as the role of forced molt in colonization of the hen. Pre- and post-harvest mitigation strategies are also discussed.     

Collection of daily patient reported outcomes is feasible and demonstrates differential patient experience in chronic kidney disease

Introduction: Patient reported outcomes (PROs) are a critical metric documenting the impact of disease and treatment from the patient's perspective. A variety of generic and disease specific PRO measures (PROMs) are used in chronic kidney disease (CKD) but studies are primarily cross‐sectional. None of the available PROMs are designed for frequent iterative application. Methods: An online PROM for daily use in dialysis and CKD 4/5 patients was developed. The custom website utilised visual analogue scales to capture 6 PROs (general well being (GWB), pain, sleep, breathing, energy, and appetite). Outcomes of interest were uptake, response rates, intermodality variation, and change in PRO corresponding to predefined events. Findings: Forty‐three patients submitted at least once and 34 submitted beyond 30 days. Median follow‐up was 247 days, 64% male, age 62 ± 12 years. In individuals submitting for >30 days, dialysis patients had significantly worse median scores compared to CKD for sleep (47[32–80], 97[76–99], P = 0.003), appetite (66[50–96], 97[88–100], P = 0.008), energy (47[40–89], 84[67–96], P = 0.031), and GWB (63[49–94], 93[71–98], P = 0.026). Patients demonstrated a variety of stable bandwidths of response, deviations from this were associated with specific events e.g., acute admission, vascular procedures, disturbed fluid status, and dialysis start. Discussion: We successfully introduced an online, patient acceptable, iterative PROM that discriminates symptom burden, cross‐sectionally, and longitudinally. Further work will prospectively examine the predictive power of changes in PRO and more rigorously investigate the potential use of these methods to optimise patient care.     

界之眼 日本丰田通商株式会社办公室

作为DURA Sambient品牌服饰全日本门店的设计方sinato，一直以来颇受设计界关注。随着公司的发展，以店铺设计见长的sinato，渐渐开始尝试多元的设计，这次为丰田通商株式会社设计的办公室，可能只是他们在办公设计领域的小试牛刀，但展现出来的非凡实力，让人惊艳。同时，也告诉世人，仅用几何线条表达的简约设计，不但完美表现了办公空间所需的克制内敛，亦让空间极具识别性，一种点到即止的夸张，让整个设计带有浓厚的个性标识。     

Visual representation of malleable and rigid objects that deform as they rotate.

Most studies and theories of object recognition have addressed the perception of rigid objects. Yet, physical objects may also move in a nonrigid manner. A series of priming studies examined the conditions under which observers can recognize novel views of objects moving nonrigidly. Observers were primed with 2 views of a rotating object that were linked by apparent motion or presented statically. The apparent malleability of the rotating prime object varied such that the object appeared to be either malleable or rigid. Novel deformed views of malleable objects were primed when falling within the object's motion path. Priming patterns were significantly more restricted for deformed views of rigid objects. These results suggest that moving malleable objects may be represented as continuous events, whereas rigid objects may not. That is, object representations may be "dynamically remapped" during the analysis.of the object's motion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)