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101.
Abstract:

In 2006, the Assistant Secretary of the Army for Installations and Environment announced the Army's desire to transition to the U.S. Green Building Council's Leadership in Energy and Environmental Design for Existing Buildings rating scheme in an effort to institutionalize sustainable practices across all Army facilities. This article describes an engineering management tool developed for project managers at Fort Bragg's Directorate of Housing and Public Works used to determine the most cost-effective route to building certification and to support the Army goal of sustainability. The results expose practicing engineering managers to a significant issue concerning Army sustainability, where numerous engineering management methods are employed for more effective decision-making. Future research is needed to convert retrofit project life-cycle costs from specific location sources to national values.  相似文献   
102.
Niobium(V) oxide (Nb2O5): application to phosphoproteomics   总被引:1,自引:0,他引:1  
Proteomics-based analysis of signaling cascades relies on a growing suite of affinity resins and methods aimed at efficient enrichment of phosphorylated peptides from complex biological mixtures. Given the heterogeneity of phosphopeptides and the overlap in chemical properties between phospho- and unmodified peptides, it is likely that the use of multiple resins will provide the best combination of specificity, yield, and coverage for large-scale proteomics studies. Recently titanium and zirconium dioxides have been used successfully for enrichment of phosphopeptides. Here we report the first demonstration that niobium pentoxide (Nb 2O 5) provides for efficient enrichment and recovery ( approximately 50-100%) of phosphopeptides from simple mixtures and facilitates identification of several hundred putative sites of phosphorylation from cell lysate. Comparison of phosphorylated peptides identified from Nb 2O 5 and TiO 2 with sequences in the PhosphoELM database suggests a useful degree of divergence in the selectivity of these metal oxide resins. Collectively our data indicate that Nb 2O 5 provides efficient enrichment for phosphopeptides and offers a complementary approach for large-scale phosphoproteomics studies.  相似文献   
103.
An experimental study on the effects of an applied external electric field on the combustion behavior of solid fuels and solid propellants has been conducted. In an opposed flow burning configuration, application of an electric field was shown to extinguish a paraffin fuel and gaseous oxygen flame over a broad range of operating conditions. When subjected to the electric field, burning paraffin fuel strands were found to extinguish at various axial locations relative to the exit of the oxidizer gas jet. Extinguishment location was found to be a function of field strength as well as electrode surface area, while changes in polarity did not significantly alter the results. In addition, the combustion behaviors of two composite solid rocket propellants were studied while subjected to an external electric field. Both propellants were based on HTPB/AP combinations, with one propellant containing aluminum and the other being non‐aluminized. Application of an electric field to the composite solid rocket propellant strands demonstrated decreases in propellant burning rate under all operating conditions for both propellants including changes in polarity. The flame structure of the aluminized propellant was examined closely as the luminosity, flame length, and flame width varied significantly with field strength and burning location of the strand relative to the electrodes.  相似文献   
104.
The effects of solid particle concentration on hydraulic performance and wear need to be considered during the design of slurry transport equipment used in the petroleum and mining industries. The acoustic properties of slurry flows such as velocity, backscatter, and attenuation as a function of volume fraction of solid particles are examined in this study. An ultrasound A-mode imaging method is developed to obtain particle concentration in a flow of soda lime glass particles (diameter of 195 μm) and water slurry in a 0.0254 m diameter pipe. Based on the acoustic properties of the slurry, a technique is developed to measure local solid particle concentrations. The technique is used to obtain concentration profiles in homogeneous (vertical flow) and non-homogeneous (horizontal flow) slurry flows with solid particle concentrations ranging from 1 to 10% by volume using a window size of 0.159 cm. The profiles show average concentration within each window vs. distance from the transducer face. For horizontal flow, profiles are obtained for average flow velocities of 2.0, 3.0, and 3.5 m/s. The algorithm developed utilizes the power spectrum and attenuation measurements obtained from the homogeneous loop as calibration data in order to obtain concentration profiles in other (i.e. non-homogenous) flow regimes. A computational study using FLUENT is performed and a comparison is made with the experimental results. Reasonable agreement between the experimental and computational results is observed. The ultrasound technique has proven to be useful in characterizing slurry flows containing concentrations too high to be investigated using optical techniques.  相似文献   
105.
The aim of this preliminary study was to examine whether individuals with avoidant personality disorder (APD) could be characterized by deficits in the classification of dynamically presented facial emotional expressions. Using a community sample of adults with APD (n = 17) and non-APD controls (n = 16), speed and accuracy of facial emotional expression recognition was investigated in a task that morphs facial expressions from neutral to prototypical expressions (Multi-Morph Facial Affect Recognition Task; Blair, Colledge, Murray, & Mitchell, 2001). Results indicated that individuals with APD were significantly more likely than controls to make errors when classifying fully expressed fear. However, no differences were found between groups in the speed to correctly classify facial emotional expressions. The findings are some of the first to investigate facial emotional processing in a sample of individuals with APD and point to an underlying deficit in processing social cues that may be involved in the maintenance of APD. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
106.
Dissolved trace metal (Ag, Cd, Cu, Fe, Ni, Pb, and Zn), inorganic nutrient (NO3, NH4, PO4, H4SiO4), and DOC concentrations were measured at 43 stations during low (July 2000) and high (April 2001) river discharge conditions in surface waters of Long Island Sound (LIS). To evaluate the impact of fluvial sources to the total metal budget of the sound, samples were collected from major tributaries discharging into LIS (Thames, Quinnipiac, Housatonic, Connecticut, and East Rivers). To compare LIS with other coastal embayments, samples were also collected from five LIS coastal embayments (Manhassett Bay, Huntington Harbor, Oyster Bay, Hempstead Harbor, and Port Jefferson Harbor), which are monitored by the U.S. National Status and Trends Program. Metal and nutrient distributions identified two biogeochemical regimes within LIS: an area of relatively high nutrient and metal concentrations in the East River/Narrows region in western LIS and an area in the eastern region of the sound that had comparatively lower concentrations. Mass balance estimates indicated that, during low flow conditions, the East River was the dominant allochthonous source of most trace metals (Ag, Cd, Cu, Ni, Zn) and inorganic nutrients (NO3 and PO4); during high flow conditions, the most influential source of these constituents was the Connecticut River. Mass balance estimates also evidenced a large autochthonous source of Cu, Ni, and Zn, as their spatial distributions displayed elevated concentrations away from point sources such as the East River. Principal component analysis suggested that metal and nutrient distributions in the LIS system were influenced by different seasonal processes: remobilization from contaminated sediments, anthropogenic inputs from sewage discharges and phytoplankton scavenging during the spring freshet, and benthic remobilization during summer conditions.  相似文献   
107.
Carbon nanoparticles were synthesized from natural gas soot and functionalized with ferrocenyl moieties by using 4-ferrocenylphenyldiazonium as the reactive precursor. The incorporation of the ferrocenyl units onto the carbon nanoparticle surface was confirmed by varied spectroscopic measurements. For instance, in FTIR measurements the characteristic vibrational bands of the ferrocenyl and phenyl moieties could be clearly identified. XPS measurements showed that there were approximately 31.9 ferrocenyl units per nanoparticle. UV-vis spectroscopic measurements displayed an absorption band at ca. 465 nm which was consistent with the optical characteristics of ferrocenyl derivatives. Furthermore, with surface functionalization by the ferrocenyl moieties, the photoluminescence of the carbon nanoparticles was found to diminish in intensity and red-shift in energy with the addition of NOBF(4). This was accounted for by the formation of varied electron-accepting moieties on the particle surface, such as positively charged ferrocenium, quinone-like derivatives, and nitrosation of the aromatic rings of the graphitic cores. Interestingly, in electrochemical studies the nanoparticle-bound ferrocenyl moieties were found to exhibit two pairs of voltammetric waves with a difference of their formal potentials at about 78 mV, suggesting nanoparticle-mediated intraparticle charge delocalization at mixed valence as a result of the strong core-ligand covalent bonds and the conductive sp(2) carbon matrix of the graphitic cores. Consistent behaviors were observed in near-infrared measurements, indicating that the particles behaved analogously to a Class I/II mixed-valence compound.  相似文献   
108.
Spent nuclear fuel chemical reprocessing plants process several 103 kg of spent nuclear fuel, especially Pu isotopes, which present significant potential for terrorism (Note: ∼8 kg Pu constitutes a threat level quantity). This requires detecting actinides in transit, but also, to ensure they are not diverted. Present-day sensors disallow real-time monitoring leading to significantly non-optimal operations.  相似文献   
109.
Secondary analysis of the 2007 Australian National Children’s Nutrition and Physical Activity survey was undertaken to assess the intake and food sources of EPA, DPA and DHA (excluding supplements) in 4,487 children aged 2–16 years. An average of two 24-h dietary recalls was analysed for each child and food sources of EPA, DPA and DHA were assessed using the Australian nutrient composition database called AUSNUT 2007. Median (inter quartile range, IQR) for EPA, DPA and DHA intakes (mg/day) for 2–3, 4–8, 9–13, 14–16 year were: EPA 5.3 (1.5–14), 6.7 (1.8–18), 8.7 (2.6–23), 9.8 (2.7–28) respectively; DPA 6.2 (2.2–14), 8.2 (3.3–18), 10.8 (4.3–24), 12.2 (5–29) respectively; and DHA 3.9 (0.6–24), 5.1 (0.9–26), 6.8 (1.1–27), 7.8 (1.5–33) respectively. Energy-adjusted intakes of EPA, DPA and DHA in children who ate fish were 7.5, 2 and 16-fold higher, respectively (P < 0.001) compared to those who did not eat fish during the 2 days of the survey. Intake of total long chain n-3 PUFA was compared to the energy adjusted suggested dietary target (SDT) for Australian children and 20 % of children who ate fish during the 2 days of the survey met the SDT. Fish and seafood products were the largest contributors to DHA (76 %) and EPA (59 %) intake, while meat, poultry and game contributed to 56 % DPA. Meat consumption was 8.5 times greater than that for fish/seafood. Australian children do not consume the recommended amounts of long chain omega-3 fatty acids, especially DHA, which could be explained by low fish consumption.  相似文献   
110.
The design and preparation of porous materials with controlled structures and functionalities is crucial to a variety of absorption‐ or separation‐relevant applications, including CO2 capture. Here, novel functional polymeric materials with three‐dimensionally ordered macroporous (3DOM) structures are prepared by using colloidal crystals as templates using relatively simple, rapid, and inexpensive approaches. These ordered structures are used for the reversible CO2 capture from ambient air by humidity swing. Typically, the colloidal crystal template is synthesized from polymer latex particles of poly(methyl methacrylate) (PMMA) or polystyrene (PS). To maintain the functionality of the material, it is important to prevent the porous structure collapsing, which can occur by the hydrolysis of the ester bonds in conventional crosslinkers under basic conditions. This hydrolysis can be prevented by using a water‐soluble crosslinker containing two quaternary ammonium moieties, which can be used to prepare stable porous crosslinked polymers with the monomer (vinylbenzyl)trimethylammonium chloride (VBTMACl) and using a PMMA‐based colloidal crystal template. The hydroxide‐containing monomer and dicationic crosslinker are synthesized from their chloride precursors, avoiding the ion‐exchange step which causes shrinkage of the pores. An analysis of different methods for infiltrating the monomer solution into the colloidal crystal template shows that infiltration using capillary forces leads to fewer defects than infiltration under a partial vacuum. In addition, functional macroporous films with micrometer thickness are prepared from a template of PS‐based colloidal crystals in a thin film. In general, the colloidal crystal templated materials showed improved CO2 absorption/desorption rates and swing sizes compared to a commercially available material with similar functional groups. This work could easily be extended to create a new generation of ordered macroporous polymeric materials with tunable functionalities for other applications.  相似文献   
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