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We focused on the production of docosahexaenoic acid (DHA)-containing microbial lipids by Aurantiochytriumsp. using of defatted soybean (DS) as a nitrogen source. Defatted soybean is a plant biomass that could provide a sustainable supply at a low cost. Results showed that Aurantiochytriumsp. could not directly assimilate the DS as a nitrogen source but could grow well in a medium containing DS fermented with rice malt. When cultivated in a fermented DS (FDS) medium, Aurantiochytriumsp. showed vigorous growth with the addition of sufficient sulfate and chloride ions as inorganic nutrients without seawater salt. A novel isolated Aurantiochytriumsp. 6-2 showed 15.8 ± 3.4 g/L DHA productivity (in 54.8 ± 12.1 g/L total fatty acid production) in 1 L of the FDS medium. Therefore, DHA produced by Aurantiochytriumsp. using FDS enables a stable and sustainable DHA supply and could be an alternative source of natural DHA derived from fish oil.Graphical AbstractFor the development of novel fish feed, docosahexaenoic acid (DHA) produced by a novel isolated strain Aurantiochytriumsp. 6-2 was applied as an alternative source of DHA by using defatted soybean treated with koji.

Undergraduate engineering education in the United States is in need of reform that addresses the recruitment and retention of a diverse population of students. Change Chem is a curriculum reform model that has been created to address this issue for freshman students. This article reports on a mixed method efficacy study of Change Chem, which uses collaborative problem-based learning with model-eliciting activities to transform the discussion section of general chemistry so as to better retain freshman who are engineering majors. The results support the viability of the model as a unique approach for reinventing the discussion component of general chemistry for engineers and supporting student learning, but not for producing positive changes in self-efficacy. Revisions to the model and plans for future testing are described. Change Chem was successful in providing an authentic engineering experience for freshman engineering students, an important outcome for building identity and, potentially, retention., Undergraduate engineering education in the United States is in need of reform that addresses the recruitment and retention of a diverse population of students. Nationally, the dropout rate for students [...]

To present the detailed history of three cervical cancer patients with rectovaginal fistula, who had undergone radiotherapy.

Rationale: Stigma permeates disability experiences and compounds disability-related challenges.Objective: Identify individual and environmental factors of stigmatizing experiences of college students with learning disabilities (LDs) and attention-deficit/hyperactivity disorder (ADHD).Methodology: A qualitative descriptive design was used with a thematic analysis of 30 transcripts from group discussions among four cohorts of undergraduates with LD/ADHD (N= 52). The Person-Environment-Occupation-Performance Model was used in interpreting the stigmatizing experiences.Findings: The themes Perceived Misconceptionsand Stigmatizing Actionsdescribe key social-environmental factors. The theme Overcoming Stigmatizing Experienceselucidates key skills and processes for developing stigma resilience. These skills and processes were anchored in self-awareness and personally contextualized understanding of disability-related challenges and strengths, which were fostered during positive interactions with supportive others, such as instructors and mentors.Implications: Findings illustrate the biopsychosocial nature of stigma and highlight the role of individual and social-environmental factors in building stigma resilience among young adults with LD/ADHD.

ABSTRACTDue to concerns about adverse health effects associated with inhalation of atmospheric polycyclic aromatic hydrocarbons (PAHs), 30 ambient air samples were obtained at an air quality monitoring station in Palm Beach County, Florida, from March 2013 to March 2014. The ambient PAH concentration measurements and fractional emission rates of known sources were incorporated into a chemical mass balance model, CMB8.2, developed by EPA, to apportion contributions of three major PAH sources including preharvest sugarcane burning, mobile vehicles, and wildland fires. Strong association between the number of benzene rings and source contribution was found, and mobile vehicles were identified to be the prevailing source (contribution ≥56%) for the observed PAHs concentration with lower molecular weights (four or fewer benzene rings) throughout the year. Preharvest sugarcane burning was the primary contributing source for PAHs with relatively higher molecular weights (five or more benzene rings) during the sugarcane burning season (from October to May of the next year). Source contribution of wildland fires varied among PAH compounds but was consistently lower than for sugarcane burning during the sugarcane harvest season. Determining the major sources responsible for ground-level PAHs serves as a tool to improving management strategies for PAH emitting sources and a step toward better protection of the health of residents in terms of exposure to PAHs. The results obtain insight into temporal dominance of PAH polluting sources for those residential areas located near sugarcane burning facilities and have implications beyond Palm Beach County, in areas with high concerns of PAHs and their linked sources.Implications: Source apportionment of atmospheric polycyclic hydrocarbons (PAHs) in Palm Beach County, Florida, meant to estimate contributions of major sources in PAH concentrations measured at Belle Glade City of Palm Beach County. Number of benzene rings was found to be the key parameter in determining the source with the prevailing contribution. Mobile vehicle sources showed a higher contribution for species with four or fewer benzene rings, whereas sugarcane burning contributed more for species with five or more benzene rings. Results from this study encourage more control for sugarcane burns and help to better manage authorization of the sugarcane burning incidents and more restrictive transportation plans to limit PAH emissions from mobile vehicles.

This paper specifically addresses the effect of changing the constant temperature region of the sintering temperature curve in manufacturing nickel powder capillary structure (wick) on the performance of a flat loop heat pipe (FLHP). The sintering temperature curve is composed of three regions: a region of increasing temperature, a region of constant temperature, and a region of decreasing temperature, with the sintering time and temperature in the region of constant temperature having significant effect on the permeability of the wick. In this study, for wick manufacturing the temperatures in this region tested range from 550°C to 650°C and the time from 30 minutes to 60 minutes. The properties and internal parameters of the wick are measured, and the wick is placed into FLHP for performance testing. Experimental results show that at sintering temperature of 550°C and lasting about 45 minutes, maximum heat load is 200W, minimum thermal resistance is 0.32°C/W, permeability is , porosity is 66%, effective porosity is 3.8and heat flux is around 21W/cm2; related literatures have only reported maximum heat load increase of 25%.

In this paper, the key parameters and functions for quantification of temperature creep stress were offered. These key parameters established the creep-heat-change fluctuation on fully graded concrete. The information is helpful for simulation of super arch dam concrete pouring process.

Implemented, based on practical engineering projects, is a statistical analysis of strata soil characteristics and geological columns sampled from the main embankment of Yangtse Rive in southern Jingzhou zone of China. Furthermore, it was verified under Kolomogorov-Smirnov theory that this assumption, namely, the statistical hypothesis of Gaussian probability distribution for random permeability tensors of soils to be submitted into the stochastic seepage field simulation would be accepted by the statistical testing. By the help of numerical analysis for stochastic seepage fields simulations using three dimensional finite element method as well as the rationality of simulated stochastic results, investigated were various statistical characteristics and random natures in random seepage fields of the main embankment of Yangtse Rive in southern Jingzhou zone of China. Meanwhile, the developed model was also examined through statistical testing. Especially, as a stochastic boundary condition, the random variation of upstream and downstream water level was taken into account of three-dimensional finite element model in practical analysis for the random seepage field simulations, by which, it has been realized deeply to describe disturbed effects of the boundary randomness due to variability of downstream and upstream water level over variabilities of simulated results presented by vector series of the random seepage field. Furthermore，the function of some safeguards to set up against the seepage problem，such as sheet-pile breakwater and catch-water，as the turbulence of complex boundary condition together with the effects of variability of soil permeability has been analyzed for description of influence of them on the hydraulic potential distributed in the random seepage field and the random evolution of stochastic seepage field under these comprehensive aspects has also been compared with the result obtained by determinate analysis for the corresponding steady seepage field problem. Philosophy deduced in this paper presents the necessity，feasibility and practicability of employing stochastic studies in seepage field problems. Meanwhile, sensitivities of random seepage field hydraulic gradient and downstream exit height were studied upon the variation of permeability and boundary conditions of the main embankment of Yangtse Rive in southern Jingzhou zone of China, by which, broadened is the research domain on seepage field evolution under uncertain numerical coverage.

Inclusive of the consideration for Solid-Liquid double phase character of dike construction, fuzzy comprehensive judgement system model was set up on the basis of Analytic Hierarchy Process as well as Fuzzy Consistency Theorem. With normal membership of fuzzy function, dike construction safety comprehensive judgement was realized by the help of weighted theorem that had been fabricated in the foregoing contents. With indirect theorem of model discrimination, generalized multi-dimension weighted fuzzy discriminating model was set up on the basis of fuzzy comprehensive evaluation. Furthermore, dike section system safety model discrimination for representative dike section was realized and sensitivity analysis for model system was carried out.

Owing to the complexity of geo-engineering seepage problems influenced by different random factors, three-dimensional simulation and analysis of the stochastic seepage field plays an important role in engineering applications. A three-dimensional anisotropic heterogeneous steady random seepage model was developed on the basis of the finite element method. A statistical analysis of the distribution characteristics of soil parameters sampled from the main embankment of the Yangtze River in the Southern Jingzhou zone of China was conducted. The Kolomogorov-Smirnov test verified the statistical hypothesis that the permeability coefficient tensor has a Gaussian distribution. With the help of numerical analysis of the stochastic seepage field using the developed model, various statistical and random characteristics of the stochastic seepage field of the main embankment of the Yangtze River in the Southern Jingzhou zone of China were investigated. The model was also examined with statistical testing. Through the introduction of random variation of the upstream and downstream water levels into the model, the effects of the boundary randomness due to variation of the downstream and upstream water levels on the variation of simulated results presented with a vector series of the random seepage field were analyzed. Furthermore, the combined influence of the variation of the soil permeability coefficient and such seepage resistance measures as the cut-off wall and relief ditch on the hydraulic head distribution was analyzed and compared with the results obtained by determinate analysis. Meanwhile, sensitivities of the hydraulic gradient and downstream exit height to the variation of boundary water level were studied. The validity of the simulated results was verified by stochastic testing and measured data. The developed model provides more detail and a full stochastic algorithm to characterize and analyze three-dimensional stochastic seepage field problems.

We developed the simple method of soymilk cream production from the high-fat soymilk, which was prepared by papain digestion and heat treatment. As a result of the treatment, high-fat soymilk was aggregated and it became possible to separate soymilk cream as the surface fraction by low-speed centrifugation (6000 × g, 10 min).

TiO2/activated carbon composite photocatalyst was prepared by a microwave-assisted impregnation method and was employed for the removal of methanol from humid air streams. A commercial microwave oven (800 W) was used as the microwave source. Under 2450 MHz microwave irradiation, titanium tetra-isopropoxide (TTIP) was quickly hydrolyzed and anatase TiO2 was formed in a short time (<20 min). As a result of the volumetric heating and selective heating of the microwave, the solvent and byproducts were quickly removed which reduced energy consumption and processing time. The formed submicrometer TiO2 particles mainly deposited on the external surface of carbon. In a packed bed reactor with an empty bed contact time of 0.35 s, the prepared materials maintained a 40% removal efficiency at an inlet methanol concentration of 39 ppm. When the TTIP conversion was complete, neither the irradiation time nor the water/TTIP ratio could further change the photocatalytic activity.

AbstractNanoparticles are a class of materials with properties distinctively different from their bulk and molecular counterparts. A critical review of the very broad topic of environmental nanoparticles is presented. Because of the vast nature of the topic, the review is focused primarily on gas-borne nanoparticles. The “life history of nanoparticles” is presented, tracking it from its formation to its potential use and eventual fate in the environment. Nanoparticle sources, anthropogenic emissions from industrial and occupational settings, and conversion and formation in the atmosphere are discussed. The ability to characterize and capture these nanoparticles (as would be necessary in a nanoparticle production system), as well as their control (of emissions from an industrial source) is discussed. A description on the use of nanoparticles in environmental technologies and the potential impact on the energy sector is provided. The potential effects on human health and the environment, both adverse and beneficial, are important aspects that need to be considered. As will be evident, the study of “environmental nanoparticles” is a new and fast-growing field. Much work remains to be done before we can fully harness the advantages of nanoparticles and ensure that there are no potential adverse consequences. A set of recommendations for additional work in each area is provided.

Integrating materials with different functionalities into a composite material to obtain synergetic properties has generated considerable interest in various scientific and technical fields. In this study, a dry-mechanical coating process was used to fix nanosized Al2O3and CuO particles directly onto the surface of Al2O3fiber substrates by employing high shear and compression forces. The resulting composite materials showed good dispersion and homogeneous distribution of Al2O3and CuO nanoparticles. Important coating parameters, including initial particle loadings and processing times were investigated for their effects on coating characteristics and product properties. The experimental results showed that the product surface area increased with higher nanoparticle loadings. The degree of dispersion and homogenous distribution of Al2O3nanoparticles with CuO nanoparticles increased with the processing time. Additionally, the crystalline phase of raw materials was preserved during the coating process under the conditions studied in this work.

A novel high surface area SiO2–TiO2composite has been developed for elemental mercury vapor removal from combustion sources. The composite exhibits synergistic adsorption and photocatalytic oxidation. Mercury vapor in the gas stream is adsorbed, oxidized and stays on the composite. The composite has demonstrated a high mercury capacity (1512ug/g) although in its current 3-mm pellet form only the outer layer is effectively utilized. The loading of 13% TiO2shows the best removal, both with and without UV irradiation. Increasing TiO2loading beyond this level does not enhance the removal further. It has also been observed that the composite after being 'activated' by photocatalytic oxidation has better performance, probably due to the change of surface functional groups. The examination of the effects of flow velocity reveals that mass transfer is the rate limiting step. Relative humidity has been found to impede adsorption therefore decreasing the overall removal efficiency. By rinsing with acid, both the deposited mercury and composite can be regenerated.

Equilibrium analyses are carried out to determine the potential sorbent materials for effective chemisorption of arsenic in combustion systems. Al-, Fe-, Li-, Na-, K-, Be-, Mg-, Ca-based sorbents are found to be effective. Excellent removal of arsenic is achieved in a wide range of temperatures. However, the effectiveness of these sorbents may be reduced when chlorine or sulfur is present in the system. The presence of chlorine in the system greatly reduces the performance of alkali metal and Fe-based sorbents due to the formation of chlorides. The impact of chlorine on alkaline earth metal and Al-based sorbents is found to be less significant. The presence of sulfur reduces the effectiveness of most sorbents due to the formation of sulfates. The only exception is Al-based sorbent. The affinity to adsorb arsenic generally follows the order: Li > K > Na > Al > Ca > Mg > Fe > Be, if there is no chlorine or sulfur in the system. However, the order of effectiveness will be altered if chlorine or sulfur is present in the system. The analyses establish the understanding of how various parameters affect the effectiveness of the sorption process.

Condensational growth of monodisperse aerosols in a system with limited vapor is studied. The equations for particle size and vapor concentration variation due to condensation are derived for the free molecular and continuum regimes, respectively. The corresponding condensation characteristic times for both size regimes are also developed. The particle size increase and vapor concentration decrease in a system with a limited vapor source are examined for varying surface vapor concentration and particle loading. The differences in the characteristic time expression derived in this work and those developed previously for constant particle size and unlimited vapor source are discussed. The expression of the condensation characteristic time developed is used to study the effect of sample aerosol concentration on the operation of the condensation particle counter, and compared to the characteristic times of other mechanisms such as nucleation, coagulation, and chemical reaction. The characteristic time estimation is shown to be a convenient and effective tool for estimating the relative importance of condensation in comparison to other concurrently occurring mechanisms in the system.

The discrete-sectional model is an important tool used to study aerosol dynamics, although it suffers inherent numerical diffusion errors that are dependent on the model parameters including section spacing, numerically conserved aerosol property, and number of discrete sizes. An analytical evaluation of the errors due to the deviations of the derived aerosol properties in the sectional formulation and the interchange between discrete-size and sectional aerosols is carried out. The errors are larger if the difference in the aerosol property function index (ξ) between the derived and conserved properties is larger. Results of parametric studies are reported for condensation and coagulation systems. The results for condensation systems show that the υ-model is better than the n-model and the υ2-model in predicting the integral properties of the size distribution. However, the deviation in the results between the n-model, υ-model, and υ2-model reduces as the section spacing is decreased. A finite value of the geometric standard deviation (σg) is obtained for a specific section spacing and is independent of the chosen conserved aerosol property. The results for coagulation systems also show that the υ-model is better in predicting N, V, and υg, although the υ2-model is better in predicting the second volume moment, V2, and σg. The inclusion of a larger number of discrete sizes gives more precise description of aerosol dynamics for the molecular clusters, although the effect is rather insignificant for the number greater than 20. It is also found that the discrete formulation possesses numerical diffusion in simulating a condensation process.

A potential method of control of toxic metallic emissions is the use of sorbents for physical and chemical capture of toxic metal species. Equilibrium calculations have been used to deteimine the feasibility of using sorbents and to identify optimal operating regimes for maximum removal of melallic species. Three different sorbents are analyzed for capture of seven toxic metallic species encountered in coal combustion and waste incineration. The results of the simulation are compared to the limited available data reported in the literature. The speciation of metallic species is determined for typical coal combustion conditions and a parametric evaluation of metal-sorbent reactions is carried out. The role of chlorine content on the capture efficiencies is established.

ABSTRACTThis paper constitutes a review of the control of toxic metal emissions using sorbents. The objective of sorbent-in-jection methods is to effectively capture the metal species (preferably transform it to an environmentally benign fo rm) and to suppress the fraction in the submicrometer mode. The design of an effective sor-bent-injection methodology thus requires an understanding of the fate of the metallic species and its transformation pathways (transfer to the gas phase, subsequent chemistry at high temperatures, and aerosol formation and growth dynamics) in the combustor. Several different sorbent methodologies used for metals capture are discussed, and a mechanistic description is provided. The need for further experimentation and pilot scale testing is also emphasized.

Learning disabilities and attention disorders (LD/AD) are highly prevalent neurodevelopmental conditions that influence developmental trajectories and whose impacts exist throughout the life course. Self-advocacy skills are critical for college students with LD/AD, which are underpinned by understanding of self and one's disability.

The characterisation of the capacitance matrix of a multilayer and multiconductor transmission-line system is very important in the development of microwave integrated circuits. Many practical multilayer and multiconductor configurations are just special cases of the general configuration described in the letter. The method presented is based on the variational principle. The determination of the capacitance matrix of a generalised N-layer and N-strip transmission-line system is programmable on a digital computer. It should be realised that the transverse-transmission-line concept does indeed make the application of the variational analysis to a multilayer and multiconductor system a relatively simple task.