Flow cytometric techniques were used to measure the cytological and biochemical damage to respiratory tract cells in animals exposed to particulates. Hamsters were exposed to raw and spent oil shale particulates and silica by intratracheal instillation. Exfoliated lung cells were obtained by sacrificing the animals and lavaging the respiratory tract posterior to the trachea with saline. Cell samples were fixed in ethanol and stained with mithramycin for fluorescence analysis of DNA content. DNA content distributions from hamsters exposed to spent oil shale and silica particulates showed atypical changes 28 to 35 days later. Cell counts and total numbers of macrophages, leukocytes, and epithelial cells in the lavage fluid also showed marked changes related to time after exposure.
An in vitro system for studying Pu uptake by, and removal from, macrophages was developed to provide data for the actinide therapy program. We have shown that "2"3"9PuO_2 particle uptake in vitro resembles the process in vivo with respect to the intracellular localization of phagocytized particles. At the end of 7 days of culture of Pu-loaded cells, 54% of the cells were viable even though 71% of the cells in the culture initially contained enough "2"3"9PuO_2 to deliver more than 53 intracellular #alpha#-disintegrations.
This report documents the collaborative effort between the United States and Canada to investigate the impact of process-induced defects on strength and stiffness under static and fatigue loading and for low-cost composite aircraft structures, in particul...
The particulate matter of a light-duty diesel engine was characterized in its morphology, sizes, internal microstructures, and fractal geometry. A thermophoretic sampling system was employed to collect particulates directly from the exhaust manifold of a 1.7-liter turbocharged common-rail direct-injection diesel engine. The particulate samples collected at various engine-operating conditions were then analyzed by using a high-resolution transmission electron microscope (TEM) and an image processing/data acquisition system. Results showed that mean primary particle diameters (dp), and radii of gyration (Rg), ranged from 19.4 nm to 32.5 nm and 77.4 nm to 134.1 nm, respectively, through the entire engine-operating conditions of 675 rpm (idling) to 4000 rpm and 0% to 100% loads. It was also revealed that the other important parameters sensitive to the particulate formation, such as ...
Biodiesel is an alternative fuel for internal combustion engines. It can reduce carbon monoxide (CO), hydrocarbon (HC) and particulate matter (PM) emissions, compared with diesel fuel, but there is also an increase in nitrogen oxides (NOx) emission. This study is aimed to compare the effect of applying a biodiesel with either 10% blended methanol or 10% fumigation methanol. The biodiesel used in this study was converted from waste cooking oil. Experiments were performed on a 4-cylinder naturally aspirated direct injection diesel engine operating at a constant speed of 1800 rev/min with five different engine loads. The results indicate a reduction of CO{sub 2}, NOx, and particulate mass emissions and a reduction in mean particle diameter, in both cases, compared with diesel fuel. It is of interest to compare the two modes of fueling with methanol in combination with biodiesel. For the blended mode, there is a slightly higher ...
We had previously identified a macrophage surface protein whose expression is highly induced, transient, and specific, as it is restricted to actively fusing macrophages in vitro and in vivo. This protein...Full Text Available
Cells of the mononuclear phagocyte lineage have the capability to adhere to and fuse with each other and to differentiate into osteoclasts and giant cells. To investigate the macrophage adhesion/fusion...Full Text Available
The present study describes pathologic findings and immunohistochemical diagnosis of canine visceral leishmaniasis (CVL) in 22 dogs who died naturally in the Aegean region of Turkey. At necropsy, lymphadenomegaly, hepatosplenomegaly, hepatic, and nephrosclerotic lesions were conspicuous. Histopathologically, chronic inflammatory reactions of the spleen, lymph nodes, bone marrow, liver, and skin were marked findings. Cytological and histological examinations showed macrophagesloaded with Leishmania amastigotes in these organs. Immunohistochemistry revealed that immunolabeling of amastigotes and/or parasite antigen, especially in the lymph nodes, spleen, bone marrow, liver, and skin, and occasionally, in the kidneys, intestines and lungs. Our laboratory results showed that immunohistochemis...
Previous studies suggest that the radiosensitivity and origin of tissue macrophage precursors differ from those of hemopoietic macrophage colony-forming units (CFU-Ms) committed to macrophage-lineage cells. We assessed the origins of tissue macrophage colony-forming cells (M-CFCs) in mice by comparing their kinetics and radiosensitivities in the normal steady state and under the conditions of bone marrow depletion by [sup 89]Sr-administration and/or splenectomy. The results indicate that the radiosensitive peritoneal M-CFCs elicited by thioglycollate are derived from bone marrow macrophage precursors; where as alveolar M-CFCs, which are radioresistant, are self-sustained locally and independent of hemopoietic macrophage precursors. In contrast, highly radiosensitive liver M-CFCs are probably derived from CFU-Ms that appear to be propagated in the spleen in ...
In 1991, the air quality monitoring program in Alberta consisted of continuous, intermittent, static, portable, mobile, and acid precipitation monitoring networks. The air quality monitoring networks are described and results from the continuous, intermittent, static, and acid precipitation networks are summarized. Regulations and guidelines for individual pollutants are discussed in detail. Pollutants monitored continuously (1-h average basis) include ammonia, CO, coefficient of haze, H{sub 2}S, nitrogen oxides, ozone, SO{sub 2}, and total hydrocarbons. Good air quality was observed most of the time at all continuous monitoring stations in 1991. The frequency of good air quality ratings ranged from 81% at the Edmonton northwest station to 98% at the Fort McMurray station. Intermittent monitoring (every 6th day) was conducted for total suspended particulates and for vinyl chloride monomers in the Fort Saskatchewan area. Chemical analyses of benzo(a)pyrene and lead ...
The effect of Escherichia coli lipopolysaccharide (LPS) on the expression of major histocompatibility complex (MHC) class II molecules by bovine mammary macrophages was examined. The ability of LPS-treated...Full Text Available
The phagocytic and killing abilities of heifer mammary gland macrophages (M phi) and neutrophils were evaluated after exposure to recombinant bovine interferon-gamma (rBoIFN-gamma) stimulation in vitro....Full Text Available
To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that...Full Text Available
BackgroundMacrophages (MΦs) utilize macropinocytosis to integrate immune and metabolic signals in order to initiate an effective immune response. Diabetes is characterized...Full Text Available
The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII...Full Text Available
BackgroundHuman immunodeficiency virus type 1 (HIV-1) infection frequently causes neurologic disease, which is the result of viral replication and activation of macrophages and microglia...Full Text Available
To study the expression of Fc receptors in human alveolar macrophages (AM), the cells were collected from 12 healthy controls and 22 patients with sarcoidosis and the activity involved in binding to...Full Text Available
Eosinophils are associated with helminth immunity and allergy, often in conjunction with alternatively activated macrophages (AAMs). Adipose tissue AAMs are necessary to maintain glucose homeostasis...Full Text Available
Macrophage phagocytosis is an essential biological process in host defense and requires large amounts of energy. To date, glucose is believed to represent the prime substrate for ATP production in macrophages....Full Text Available
B lymphocytes can function independently as efficient APCs. However, our previous studies demonstrate that both dendritic cells and macrophages are necessary to propagate immune responses initiated...Full Text Available
The translocation of particles from the alveolar compartment to the pleural space and tracheobronchial lymph nodes was investigated in rats over a 30 day period following the intrapulmonary instillation of 4 x 10/sup 8/ polystyrene microspheres (1.9 ..mu..m dia.). In initial studies, approx. =10/sup 4/ particles were found in the pleural space compartment on Days 1, 14 and 30 after particle deposition, and most of these were cell-associated. Subsequent pleural space studies indicated, however, that the particles found in this compartment were, at least in part, due to the pleural lavage technique, and, unlike observations reported for some fibers, the translocation of the particles used in our study to the pleural space does not represent an important lung clearance pathway. In regard to particle clearance to the tracheobronchial lymph nodes, the accumulation of particles, most of which were extracellular, kinetically was biphasic with the most rapid phase occurring within the first 24 ...
A new method, near-infrared laser desorption/ionization aerosol mass spectrometry (NIR-LDI-AMS), is described for the real time analysis of organic aerosols at atmospherically relevant mass loadings. Use of a single NIR laser pulse to vaporize and ionize particle components deposited on an aluminum probe results in minimal fragmentation to produce exclusively intact pseudomolecular anions at [M-H](-). Limits of detection (total particulate mass sampled) for oxidized compounds of relevance to atmospheric primary and secondary organic aerosol range from 89 fg for pinic acid to 8.8 pg for cholesterol. NIR-LDI-AMS was used in conjunction with the University of Vermont Environmental Chamber to study secondary organic aerosol (SOA) formation from ozonolysis of limonene at total aerosol mass loadings ranging from 3.2 to 25.0 ?g m(-3) and with a time resolution of several minutes. NIR-LDI-AMS permitted direct delineation between ...
Discontinuously reinforced aluminium-based composites containing particulate or whisker SiC reinforcements at different volume fractions, were produced via a powder-route. Isothermal creep tests have been carried out at 270, 300 and 320 C. During these tests axial and transverse strains were monitored using a non-contacting laser scanning extensometer arrangement. At the same time neutron diffraction has been used to measure the elastic phase strain evolution with composite creep deformation. It was found that after the initial loading the phase strains remained essentially constant during primary and secondary creep. This indicates that the initial matrix/reinforcement inelastic misfits remain largely unchanged, probably due to the setting up of a dynamic equilibrium between misfit generation and stress relaxation. For each system, the neutron data has been combined with Eshelby modelling to obtain a measure of the load ...
Sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) has worse outcome because of multiresistance to a large group of antibiotics, which may lead to death from septic shock. In the present study, we firstly found that artesunate in combination with oxacillin was capable of protecting mice challenged with live MRSA WHO-2 (WHO-2) and the protection was related to the reduced TNF-a and IL-6 levels and decreased bacterial load. Based on above results, artesunate was further investigated from two aspects in vitro, anti-inflammation effect and antibacterial enhancement effect on antibiotics. Artesunate not only inhibited TNF-a and IL-6 release but also inhibited mRNA and protein expressions of TLR2 and Nod2, two important receptors, in murine peritoneal macrophages stimulated wit...
Adenosine triphosphate (ATP) is an indicator of living biomass in marine particulates. This report details the method used by Lawrence Berkeley Laboratory to analyze particulate ATP in samples taken from oligotrophic, tropical ocean waters. It represents a synthesis of previously published methods.
A method is described for determining the particulate contamination in miniature ball bearings in which the bearing is flushed with a solvent that is then filtered. The particles that are collected on the filter are examined by optical microscopy.
A remarkable aspect of the interaction of Cryptococcus neoformans with mammalian hosts is a consistent increase in capsule volume. Given...Full Text Available
... as far as mammary development is concerned but carries the NF-κB reporter, there is diffuse NF-κB activity throughout the epithelial tissue that is ...
Legionella pneumophila is the causative agent of Legionnaires’ disease, an acute pulmonary infection. L. pneumophila is able to infect and multiply in both...Full Text Available
Immunomodulation by environmental chemical contaminants and the role immune parameters play in toxicity and risk assessment studies is of increasing concern. Although considerable evidence has indicated...Full Text Available
Several old and new observations suggest the existence in Crohn's disease of a phagocytic disorder of macrophages related to impaired bactericidal activity of host cells or to the presence of invasive bacteria that have developed strategies to counteract macrophage killing. It was recently reported that disordered macrophage cytokine secretion underlies impaired acute inflammation and bacterial clearance in Crohn's disease. Secretion of proinflammatory cytokines by CD macrophages was impaired in response to E. coli or specific Toll-like receptor agonists. In addition, major advances in the etiology of Crohn's disease came from the existence of polymorphism in NOD2 and autophagy-related susceptibility genes (ATG16L1 and IRGM) in patients and from the identification of the presence of adhere...
Aggregatibacter (Actinobacillus) actinomycetemcomitans is a facultative anaerobic gram-negative bacterium associated with severe forms of periodontitis. A leukotoxin, which belongs...Full Text Available
The biological activity of coir fibre, coir ash and their components were investigated in vitro by measuring the haemolytic activity and macrophage cytotoxicity. In vivo studies carried out by injecting guinea pigs intratracheally with coir fibres resulted in resolving granulomas. The observed haemolytic activity and macrophage cytotoxicity was more marked with coir ash compared with coir fibres. Chemical analysis of coir ash revealed the presence of toxic chemical constituents in appreciable amounts. PMID:6283694
A new exhaust cleaning system is introduced, aiming to remarkably reduce NOx emission using a type of EGR method (hybrid EGR) of feeding back the exhaust from an exhaust cleaning ternary catalyst provided gasoline engine to the Diesel engine intake on one hand and, on the other hand, aiming to reduce even the emitted particulates using an exhaust supplying gasoline engine driven supercharger for an enhanced Diesel engine supercharging. The hybrid EGR system used here can uniformly reduce the emitted NOx under any load conditions and, as compared with the conventional type, is two to three times more effective, with the EGR rate kept constant. The exhaust concentration is approximately 10%. An sample of the hybrid EGR was simulated, and it was shown, as compared with the original non-supercharged Diesel engine, that the emitted NOx decreased to 1/3 or 1/4, that the exhaust concentration was approximately the same, and that the total fuel ...
Experiments were completed to study intermittent coal-water slurry (CWS) fuel sprays injected from an electronically-controlled accumulator injector system. A new synchronization technique was developed using the light extinction signal as a triggering source for the data taking initiation with a laser diffraction particle analyzing (LDPA) technique. This technique allowed measurement of SMDs near the spray tip where the light extinction was low and the data were free from the multiscattering bias. Coal-water slurry fuel with 50% coal loading in mass containing 5 {mu}m mass median diameter coal particulates was considered. A correlation of the SMD with the injection conditions was determined which should show a satisfactory agreement with the measured SMD data. The spray SMD showed an increase with the distance of the axial measurement location and with the ambient gas density, and showed a decrease with increasing injection pressure.
Streptococcus pneumoniae colonizes the mucosal surface of the human upper respiratory tract. A colonization event is gradually cleared through phagocytosis by monocytes/macrophages that are recruited to the airway lumen. Here, we sought to define the bacterial and host factors that promote monocyte/macrophage influx and S. pneumoniae clearance using intranasal bacterial challenge in mice. We found that the recruitment of monocytes/macrophages required their expression of the chemokine receptor CCR2 and correlated with expression of the CCR2 ligand CCL2. Production of CCL2 and monocyte/macrophage recruitment were deficient in mice lacking digestion of peptidoglycan by lysozyme (LysM) and cytosolic sensing of the products of digestion by Nod2. Ex vivo macrophages produced CCL2 following bacterial uptake, digestion by LysM, and sensing of peptidoglycan by Nod2. Sensing of digested ...
Cancer cells recruit monocytes, macrophages and other inflammatory cells by producing abundant chemoattractants and growth factors, such as macrophage colony-stimulating factor (M-CSF/CSF-1) and monocyte chemoattractant protein-1 (MCP-1/CCL2), to promote tumor growth and dissemination. An understanding of the mechanisms that target cancer cells and regulate tumor microenvironment is essential in designing anticancer therapies. Here, we showed that serum amyloid-A (SAA) and cathelicidin (LL-37) stimulated M-CSF and MCP-1 expression with or without lipopolysaccharide (LPS) administration; conversely, lipoxin-A4 (LXA4) and annexin-A1 (ANXA1) inhibited LPS-induced M-CSF and MCP-1 production by human (HepG2) and mouse (H22) hepatocellular carcinoma cells (HCCs). The effects of LXA4, ANXA1, SAA ...
BackgroundRecent research highlights the promise of remotely sensed aerosol optical depth (AOD) as a proxy for ground-level particulate matter with aerodynamic diameter ≤...Full Text Available
The food ingestion consequences due to radioactive particulates of an accidental release, scenario 1-RD-3, are evaluated for Savannah River Technology Center. The sizes of land areas requiring the protective action of food interdiction are calculated. The consequences of the particulate portion of the release are evaluated with the HOTSPOT model and an EXCEL spreadsheet for particulates.
AbstractThe tick-borne protozoan parasite Theileria annulata causes a debilitating disease of cattle called Tropical Theileriosis. The parasite predominantly invades...Full Text Available
CBA/Ca mice were infected by either the intravenous or intraperitoneal route with Mycobacterium microti and the subsequent changes in local macrophage populations examined. Following infection, the number of macrophages increased and they showed greater expression of both MHC Class II molecules. This response was not dependent on viability of the mycobacteria, in contrast to reports with other microorganisms such as Listeria. Studies in sublethally irradiated mice indicated that persistent antigen could give rise to a response after a period of host recovery which was radiation dose dependent. This procedure also highlighted differences in the regulation of different murine class II antigens in vivo, as seen by delayed re-expression of I-E antigens. Macrophage accessory cell function, as assessed by an in vitro T cell proliferation assay, correlated with Ia expression after fixation, but not after indomethacin treatment; ...
Macrophage activation by the proinflammatory cytokine interferon-γ (IFN-γ) is a critical component of the host innate response to bacterial pathogenesis. However, the precise nature...Full Text Available
Antibodies to myelin oligodendrocyte glycoprotein (MOG) have been implicated in Multiple Sclerosis demyelination through activation of complement and/or macrophage-effector processes. We presented...Full Text Available
The use of infectious pathogens has allowed the detection of the development of synergism between pathogens and ubiquitous environmental chemical contaminants. This synergism has been demonstrated to...Full Text Available
Neuronal death is known to trigger reactive microgliosis. However, little is known regarding the manner by which microglia are activated by injured neurons and how microgliosis participates...Full Text Available
Despite the demonstrated clinical efficacy of CD20 monoclonal antibody (mAb) for lymphoma therapy, the in vivo mechanisms of tumor depletion remain controversial and variable. To identify the molecular...Full Text Available
Host cells use metabolic signaling through the LXRα nuclear receptor to defend against Listeria monocytogenes infection. 25-Hydroxycholesterol is a natural ligand of LXRs that...Full Text Available
Exteriorized phosphatidylserine (PS) residues in apoptotic cells trigger rapid phagocytosis by macrophage scavenger receptor pathways. Mimicking apoptosis with liposomes containing PS may represent...Full Text Available
Dectin-1, the major β-glucan receptor in leukocytes, triggers an effective immune response upon fungal recognition. Here we use sortase-mediated transpeptidation, a technique that allows placement...Full Text Available
The influence of pretreatment of Escherichia coli and Staphylococcus aureus with sub-MICs of the new beta-lactam antibiotic imipenem on phagocytosis and killing by murine peritoneal macrophages and...Full Text Available
PurposeTo address the roles of the stromal derived factor-1 (SDF-1) α in the course of experimental corneal neovascularization (CNV).MethodsCNV...Full Text Available
Normal healthy volunteers underwent broncho-alveolar lavage and the cells obtained were cultured for 24 h and 48 h, either alone or in the presence of the corticosteroid, Budesonide. Cell differentials...Full Text Available
The role of intracellular Ca2+ (Ca2+i) on hematopoiesis was investigated in long term bone marrow cultures using cytokines and agonists of P2 receptors. Cytokines interleukin 3 and granulocyte/macrophage colony stimulator factor promoted a modest increase in Ca2+i concentration ([Ca2+]i) with activation of phospholipase Cgamma, MEK1/2, and Ca2+/calmodulin kinase II. Involvement of protein kinase C was restricted to stimulation with interleukin 3. In addition, these cytokines promoted proliferation (20 times) and an increase in the Gr-1(-)Mac-1+ population with participation of gap junctions (GJ). Nevertheless ATP, ADP, and UTP promoted a large increase in [Ca2+]i, moderate proliferation (6 times), a reduction in the primitive Gr-1(-)Mac-1(-)c-Kit+ population, and differentiation into macrophages without participation of GJ. It is likely that Ca2+i participates as a regulator of hematopoietic signaling: moderate increases in [Ca2+]i would be ...
Macrophages are cells of the immune system that protect organisms against invading pathogens by fulfilling critical roles in innate and adaptive immunity and inflammation. They originate from circulating...Full Text Available
The aggregation substance (AS) of Enterococcus faecalis, encoded on sex pheromone plasmids, is a surface-bound glycoprotein that mediates aggregation between bacteria thereby facilitating...Full Text Available
The authors have presented results of an investigation of wettability of SiC particulates by liquid alloys of the Al-Si-Mg system. The evaluation of wetting has been carried out through the determination of the threshold pressure for infiltration of packed SiC particulates by the liquid alloy. The results indicate that whereas Si and Mg additions do not affect wetting, in the case of the ternary alloys the contact angle decreases in an amount proportional to the content of Mg[sub 2]Si.
An experimental study was performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (RCCI) combustion mode utilizing dual-fuel approach in a light-duty, multi-cylinder diesel engine. In-cylinder fuel blending using port fuel injection of gasoline before intake valve opening (IVO) and early-cycle, direct injection of diesel fuel was used as the charge preparation and fuel blending strategy. In order to achieve the desired auto-ignition quality through the stratification of the fuel-air equivalence ratio ( ), blends of commercially available gasoline and diesel fuel were used. Engine experiments were performed at an engine speed of 2300rpm and an engine load of 4.3bar brake mean effective pressure (BMEP). It was found that significant reduction in both nitrogen oxide (NOx) and particulate matter (PM) was realized successfully through the RCCI combustion mode even without ...
In Oslo, traffic has been one of the dominating sources of air pollution in the last decade. In one part of the city where most traffic collects, two tunnels were built. A series of before and after studies was carried out in connection with the tunnels in use. Dispersion models were used as a basis for estimating exposure to nitrogen dioxide and particulate matter in two fractions. Exposure estimates were based on the results of the dispersion model providing estimates of outdoor pollutant concentrations on an hourly basis. The estimates represent concentrations in receptor points and in a square kilometre grid. The estimates were used to assess development of air pollution load in the areas, compliance with air quality guidelines, and to provide a basis for quantifying exposure-effect relationships in epidemiological studies. After both tunnels were taken in use, the pollution levels in the study areas were lower than when the traffic was on ...
ObjectivesThe objective of this meeting will be to interface the two ends of the particulate flow spectrum - those working to understand the fundamentals of granular flows and those attempting to control particulate flows in an industrial setting - to develop solutions to the complex problems presented by dense granular flows. We will aim~%~~%~to provide a forum for the interface between practical users of particulate technology and the developers of theories for understanding granular flow;~%~to present [continued...]DescriptionIn practical situations such as those met in industry where segregation and mixing are important, understanding particulate flows is complex due to the presence of polydispersity, anisotropy and complex grain morphology. In attempting to model such systems, many of these features are generally ignored, except perhaps through empirical parameter fitting. ...
... Briefly, a standard detonator (normally the Scale 1 Gap Test Donor, comprising an exploding bridgewire to initiate a low density PETN pellet and ...
In order to realize simultaneous reduction of NO{sub x} and Particulate emissions, effects of combustion chamber geometry were investigated in a high speed direct-injection diesel engine. The reentrant combustion chambers with different throat diameter were compared in terms of engine performance, combustion characteristics and emissions such as NO{sub x}, particulate and THC. The phenomena of combustion process were also observed with endoscopic high speed photography. The results showed that when the throat diameter of a reentrant combustion chamber was reduced to an extent, NO{sub x} and particulate decreased simultaneously due to retarded injection timing and the intensified squish. (author)
An inorganic particulate adsorbent of a titania-alumina is described for treating a superheated water containing radioactive materials such as cobalt ions, which is free from release of corrosive impruities, and which has a high adsorption capacity of radioactive materials and a high mechanical strength is prepared by hydrolyzing a titanium alkoxide and an aluminum alkoxide, thereby forming a hydrous titanium oxide and a hydrous aluminum oxide, respectively; precalcining the hydrous titanium oxide and aluminum oxide, mixing and molding the resulting titania and alumina into a particulate mixture thereof having a titania mole fraction of 0.2 to 0.9, and calcining the particulate mixture at 500/sup 0/-700/sup 0/C. This absorbent is effectively used in treat boiling water-type nuclear reactor core-circulating water to remove radioactive substances therefrom.
In this study, the effect of intake charge dilution with carbon dioxide on the combustion and emission characteristics of a 4-cylinder direct-injection diesel engine fueled with biodiesel, ethanol-biodiesel and methanol-biodiesel were investigated. With increase of intake CO"2 concentration, CO, HC, particulate mass concentration, particle number concentration and geometric diameter (GMD) of all fuels increased while NO"x decreased obviously. After addition of methanol and ethanol in biodiesel, the NO"x, particulate mass concentration and particle number concentration decreased at each intake CO"2 concentration, compared with biodiesel. Moreover, as the intake CO"2 concentration increased from 2% to 5.6%, particulate mass concentration of the alcohol-biodiesel blends remained almost unchan...
A high-average power (kW) infrared (IR) free-electron laser (FEL) is currently being commissioned for the Jefferson Laboratory FEL User Facility. The IR FEL is driven by a unique superconducting rf linac which is recirculated to recover electron beam power that is not radiated in the FEL. The design and installation of the vacuum system for the FEL involved particular attention to minimizing particulate contamination which could cause problems with the superconducting acceleration cavities and the high power FEL optics. Particulate contamination levels of all vacuum components were monitored during the cleaning process using laser scattering. Cleaning, transport, and installation procedures were developed to minimize the contamination of the complete system. We will summarize a data base we compiled of particulate contamination levels of the various components installed in the FEL vacuum system.
The interaction of thermal radiation with conduction and convection in thermally developing absorbing, emitting, nongray gas-particulate turbulent suspension flow through a circular tube is investigated. The contribution of thermal radiation is obtained through evaluation of the total hemispherical emittance of the particulate cloud and through evaluation of single band absorptances for molecular gases, modified to account for the interaction with the particles. The governing differential equation is derived as a (nonlinear) energy equation, coupled with integral equations to find the thermal radiation contributions. The energy equation is solved numerically by an implicit finite difference method with an iterative procedure. Qualitative results for Nusselt numbers are shown for a variety and range of parameters, such as optical thickness of particulates and single molecular gas bands, relative gas band position and band ...
The interaction of thermal radiation with conduction and convection in thermally developing absorbing, emitting, non-gray gas particulate turbulent suspension flow through a circular tube is investigated. The contribution of thermal radiation is obtained through evaluation of the total hemispherical emittance of the particulate cloud and through evaluation of single band absorptances for molecular gases, modified to account for the interaction with the particles. The governing differential equation is derived as a (nonlinear) energy equation, coupled with integral equations to find the thermal radiation contributions. The energy equation is solved numerically by an implicit finite difference with its iterative procedure. Qualitative results for Nusselt numbers are shown for a variety and range of parameters, such as optical thickness of particulates and single molecular gas bands, relative gas band position and band width, ...
An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of par...
Airborne lead particulates collected on a membrane filter were determined by the nondestructive X-ray fluorescence method. The gamma/X radionuclide source "2"4"1Am/Ag and a scintillation detector with a NaI/Tl crystal were used for the excitation and detection, respectively, of L X-rays of Pb. One can say, with reference to the obtained results, that the sensitivity and accuracy of the measurement is more than adequate for monitoring the Pb level in air. (author).
A composition of matter to treat particles entrained in flue gas, is described comprising: a caustic liquid used to adjust resistivity of the entrained particles; and inert particulate matter supporting the caustic liquid for inhibiting chemical action of the caustic liquid until used to adjust the resistivity of the entrained particles, the inert particulate matter supporting sufficient caustic liquid to adjust the resistivity of the entrained particles.
This capsule report describes a Research-Cottrell/Bahco scrubber module for sulfur dioxide and particulate emission control located at the central heat plant of Rickenbacker Air Force Base. he report also describes flue gas desulfurization technology using any fuel, including hig...
An experimental investigation was conducted to evaluate the effect of three different oxygenated compounds, diglyme, diethyl maleate and dibutyl maleate, on emissions from a Volkswagen 1.9 litre, turbocharged, direct injection diesel engine. Sampling was performed using a mini-dilution tunnel technique to obtain particulate matter and a Fourier transform infrared (FTIR) spectrometer for gaseous emissions. The particulate samples were analysed using thermal analysis and Soxhlet extraction to determine the fraction of volatile and soluble organic material respectively. All three oxygenated compounds were found to be effective at reducing particulate emissions, with the maleate compounds being more effective overall than the diglyme. Analysis of the relative contributions of changes in the soot and soluble organic fraction (SOF) to the reduction of particulate matter indicated that, for diethyl maleate and ...
An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of particle introduction, assessed using Trypan blue dye exclusion, had no effect on cell viability. In combination with a differential mobility classifier, the ...
In this study, we measured the effects of different concentrations of paraquat (0,01 mM and 1,0 mM) on the 1-"1"4CO_2 and 6-"1"4CO_2 production of rabbit lung slices and isolated alveolar macrophages, in 20% and 95% oxygen phases respectively. A 95% oxygen phase induced an increase in the 6-"1"4C-glucose oxidation of control lung slices over a 3-hour period, while the increased activity of the pentose pathway over the first 2 hours started to decline during the third hour of incubation. Paraquat (1,0mM) in 20% oxygen caused a consistent increase in the 6-"1"4CO_2 production by lung slices, but in a 95% oxygen phase gradually inhibited the 6-"1"4C-glucose oxidation over a period of 3 hours. The pentose phosphate pathway was highly significantly stimulated by 1,0 mM paraquat in 20% and 95% oxygen over 3 hours. When isolated alveolar macrophages (viability 95%) were incubated in a 20% and 95% oxygen phase respectively, both the 6-"1"4C-glucose and ...
A cDNA library was constructed from HL60 human promyelocyte poly(A)+ RNA harvested 3 h after induction of macrophage differentiation with 12-O-tetradecanoyl phorbol-13-acetate in the presence of cycloheximide....Full Text Available
In monocytes, sulfatide, a lipid from Mycobacterium tuberculosis, blocked priming for enhanced release of superoxide (O2-) by the macrophage activating factors lipopolysaccharide, gamma interferon,...Full Text Available
LRP1 is a type-1 transmembrane receptor that mediates the endocytosis of diverse ligands. LRP1 β-chain proteolysis results in release of sLRP1 that is present in human plasma. In this study,...Full Text Available
The CNS is a unique organ due to its limited capacity for immune surveillance. As macrophages of the CNS, microglia represent a population originally known for the ability to assist neuronal stability,...Full Text Available
The overall goal of the DOE fine particulate program is to ensure that the best science and technology is available for any regulatory decision-making related to the health and environmental impacts of ambient fine particulate matter and regional haze. Interest primarily lies in the particulate fraction having aerodynamic diameters of 2.5 microns and less (PM2.5). Particulates of this size are the focus of the newly established National Ambient Air Quality Standards. As such, the Federal Energy Technology Center (FETC) is establishing a fine particulate sampling station at the Center's Pittsburgh site located in South Park Township, PA. This sampling station is one of a group of stations scattered throughout Pennsylvania, West Virginia, and Ohio that constitute the Upper Ohio River Valley Project. The station is equipped with a full complement of fine ...
In a method for formulating a multi-component explosive composition, the steps are described comprising: (a) providing a defined body of unconsolidated particulate aluminum fuel granules having an average particle size within the range of 1/64-1/4 inch and an average bulk density within the range of 0.2-1.0 gm/cc; (b) providing a phase oxidizing liquid; and (c) flooding said body of particulate aluminum fuel of step (a) with the oxidizing liquid of step (b) to provide a bulk density of said mixture of oxidizing liquid and particulate aluminum fuel mass within the range of 1.2-1.7 gm/cc and provide an explosive formulation detonable at 20 C in a diameter of 4 inches by a one pound pentolite booster.
...2010-07-01 false Loading and haulage equipment; inspection and maintenance... § 77.1606 Loading and haulage equipment; inspection and maintenance. (a) Mobile loading and haulage equipment shall be inspected by a...
...position to receive material. (2) Self-loading haulage equipment used as a loading machine. In working places in which self-loading haulage equipment is operated to load material, the areas which...
If you missed the ARTE programme entitled "L'Ultime Particule" broadcast in February, you have another chance to catch it in CERN's Main Auditorium on 13 March. "L'Ultime Particule" is a documentary by the French director Michel Andrieu that seeks to explain particle physics through a contemplative quest for the research physicists of matter of today and yesteryear. Invariably kitted out in a red parka and a soft hat, the programme's investigator scours the planet and the archives in search of the research physicists who are stalking the ultimate particle, the Higgs boson, in their quest to understand the structure of matter. Naturally enough, CERN is an important stage of his journey where Michel Andrieu and his team spent several days last year. Both from the physics and metaphysical points of view, "L'Ultime Particule" is worth seeing. The film's director, Michel Andrieu, will introduce his documentary and answer ...
Biomass fuel burning leads to high levels of suspended particulate matter and hazardous chemicals in the indoor environment in countries where it is in common use, contributing significantly to indoor...Full Text Available
The present document represents an attempt to summarize the most important features of the different forms of ED-XFR as applied to the analysis of airborne particulate matter. It is intended to serve as a set of guidelines for use by participants in the IAEA's own programmes, and other scientists, who are not yet fully experienced in the application of ED-XRF to airborne particulate samples, and who wish either to make a start on using this technique or to improve their existing procedures. The methodologies for sampling described in this document are of rather general applicability. Emphasis is also placed on the sources of errors affecting the sampling of airborne particulate matter. The analytical part of the document describes the different forms of ED-XRF and their potential applications. Spectrum evaluation, a key step in X-ray spectrometry, is covered in depth, including discussion on several calibration and peak ...
School buses contribute substantially to childhood air pollution exposures yet they are rarely quantified in epidemiology studies. This paper characterizes fine particulate matter (PM2.5)...Full Text Available
Allergic asthma is characterized by airway hyperresponsiveness, inflammation, and a cellular infiltrate dominated by eosinophils. Numerous epidemiological studies have related the exacerbation of allergic...Full Text Available
The growing use of coal for heating and electric power generation and diesel engines in light duty motor vehicles will increase not only the existing atmospheric concentrations of criteria pollutants...Full Text Available
This study tried to reduce NO{sub x} and particulate emissions simultaneously in a high speed direct-injection diesel engine. Fuel-rich combustion was used to reduce NO{sub x} emission at initial combustion stage and high turbulence combustion was used to reduce particulate emission at diffusion combustion stage. Experiments were carried out to investigate the effects of high squish combustion chambers with small throat on combustion process and exhaust emissions. Results showed that in the high squish combustion chamber, both NO{sub x} and particulate emissions reduced with retarded injection timing. Endoscopic high speed photography was employed to analyze experimental results. In the original combustion chamber at the early combustion stage, the high luminosity flame tended to spread out of the cavity. Fuel-rich mixture burned slowly over the piston crown. In the high squish combustion chamber, flame rotated violently ...
Attention has shifted from the treatment of colorectal cancer (CRC) to chemoprevention using aspirin and folic acid as agents capable of preventing the onset of colon cancer. However, no sensitive...Full Text Available
Particulate (i.e. tokamak dust) has been collected from the DIII-D tokamak located at General Atomics in San Diego, CA, USA. Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Sampling was completed in four toroidal locations of the machine; the 0-90 area, the 90-180 area, the 180-270 area, and the 270-360 area. The 0 direction designates the north side of the DIII-D machine. Four tiles in each area were sampled; the first vertical tile above the floor on the centerpost, a floor tile next to the center post, a tile on the isolated ring, and the first tile up from the isolated ring on the divertor. In addition, samples were collected from underneath the floor tiles at the 275 and the 75 ...
BackgroundParticulate systems are well known to be able to deliver drugs with high efficiency and fewer adverse side effects, possibly by endocytosis of the drug carriers. On the...Full Text Available
The pharmacokinetic concepts of bioavailability and biotransformation are introduced into the assessment of public health risk from experimental data concerning the emissions of potentially mutagenic...Full Text Available
The measurement of air pollutants is no more sufficient. It is necessary to assess the risk induced by air pollution, and then to put in place actions to reduce it. The air quality monitoring takes into account different pollutants: nitrogen oxides, carbon monoxide, particulates for the traffic; sulfur dioxide and particulates for use of fuel or coal or chemical transformations in air; ozone and nitrogen dioxide from hydrocarbon and nitrogen oxides emissions; the use of simulation methods allow to calculate the concentrations levels for these pollutants taken as indicators. (N.C.)
The 8 papers in the report deal with the following areas: Introduction to diesel particulate emissions, alternative fuels, and the transit industry; Technical problems and policy issues associated with the 1991 bus emissions standards; Reducing transit bus emissions: comparative costs and benefits of methanol, particulate traps, and fuel modification; Effects of applying emissions averaging, trading, and banking to transit buses; Strategic review of heavy-duty engine emission regulations and alternate fuels; Meeting bus emissions standards--a perspective; Economic evaluation of bus maintenance contracting; Objectives for a transit-bus-fleet management data, information, and knowledge exchange.
Early effects of boron neutron capture therapy (BNCT) on malignant glioma are characterized by reduction of the enhancement area and regression of the peritumoral edema radiologically. The aim of this study was to investigate the early histological changes of tumors and inflammatory cells after BNCT in the rat brain. Rats were treated with BNCT using boronophenylalanine (BPA) 7 days after implantation of C6 glioma cells. The tumors were assessed with magnetic resonance imaging and histopathological examination at 4 days after BNCT. The mean tumor volumes were 39#+-#2 mm"3 in the BNCT group and 134#+-#18 mm"3 in the control group. In the BNCT group, tumor cells showed a less pleomorphic appearance with atypical nuclei and mitotic figures. The Ki-67 labeling index was 6.5%#+-#4.7% in the BNCT and 35%#+-#3.8% in the control group. The reactions of the inflammatory cells were examined with ED-1 as macrophage marker and OX42 as microglia marker. ED-1- and OX-42-positive ...
A new simple multi-well plate-based assay to determine monocyte differentiation-inducing activity was developed. It is based on the increase of macrophage adherence after the induction of monocyte differentiation. The assay was conducted using a human monocytic leukemia cell line, THP-1, treated with either 12-O-tetradecanoylphorbol 13-acetate or cytokines, such as tumor necrosis factor-alpha and interferon-gamma. This method is sensitive and easy to perform, especially in case of analyzing a large number of samples. PMID:17920620
A new simple multi-well plate-based assay to determine monocyte differentiation-inducing activity was developed. It is based on the increase of macrophage adherence after the induction of monocyte differentiation. The assay was conducted using a human monocytic leukemia cell line, THP-1, treated with either 12-O-tetradecanoylphorbol 13-acetate or cytokines, such as tumor necrosis factor-? and interferon-?. This method is sensitive and easy to perform, especially in case of analyzing a large number of samples.
Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced /sup 86/Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. /sup 86/Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated /sup 86/Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, ...
The purpose of this paper is to establish probabilistic models for still-water loads, based on design data, and the combined still-water and wave load effects for semi-probabilistic and probabilistic design of floating production, storage and offloading vessels (FPSO). A new still-water load model for FPSOs is proposed, based on a Poisson square-wave model, with a modified Weibull distribution for load intensity, which accounts for load control during operation. The long-term variation of wave-induced load effects is modelled by a Poisson square-wave process. A new solution for the combined effect is derived. A procedure for determining characteristic extreme values for individual and combined load effects, and load combination factors, is established. The methodology is used to illustrate...
In 2003, Vehicle Emissions Team of the Clean Air Strategic Alliance (CASA) decided to explore ways to reduce vehicle emissions such as particulate matter, nitrogen oxides, carbon monoxide, and hydrocarbons from diesel engines. One of the options for reducing emissions from diesel engines, a diesel particulate filter (DPF), is the subject of a demonstration project to test the effectiveness of the Johnson Matthey diesel particulate filter called Continuously Regenerating Technology (CRT) under cold weather conditions. The project involved filter testing between January 2003 and January 2004 on two diesel buses in Edmonton Transit System's (ETS) fleet. Vehicle exhaust emissions were tested for total hydrocarbons, nitrogen oxides, carbon monoxide, carbon dioxide, and particulate matter. The objectives of the project were to: prove the effectiveness of DPF under cold weather conditions in Alberta; ...
Most mechanical forces acting on the skeleton are generated either through impact with the ground (i.e., gravitational loading) or through muscle contractions (i.e., muscle loading). If one...Full Text Available
An estimator for the load share parameters in an equal load-share model is derived based on observing k-component parallel systems of identical components that have a continuous...Full Text Available
In this paper an attempt is made to forecast load using fuzzy neural network (FNN) for an integrated power system. Here, the proposed system uses a two stage FNN for a short term peak and average load forecasting (STPALF). The first stage FNN deals with the load forecasting and the second stage algorithm can be worked independently for network security. This technique is used to forecast load accurately on week days as well as holidays, weekends and some special occasions considering historical data of load and weather information and also take necessary control action for network security.
Quantitative estimates of lung cancer risk from exposure to diesel engine emissions were developed using data from three chronic bioassays with Fischer 344 rats. Human target organ dose was estimated with the aid of a comprehensive dosimetry model. This model accounted for rat-human differences in deposition efficiency, normal particle clearance rates, transport of particles to lung-associated lymph nodes, respiration rates, and lung surface area, as well as high-dose inhibition of particle clearance. Recent evidence indicates that the inert carbon core of the diesel particulate matter is likely to be the primary source of carcinogenicity. The epithelial tissue lining the alveoli and lower airways is the primary target site for induction of lung tumors. Dose was therefore based upon the concentration of carbon particulate matter per unit lung surface area. Unit risk estimates were developed using either a time-to-tumor or a linearized ...
The consequences of converting a facility from brown coal fuel to gas fuel were analyzed by model simulation. Treated were a district heating plant with an output of 700 TJ/yr and minor local heating sources (stoves) at a density of 1 family house per 100 m"2. Emissions of particulate matter, sulfur dioxide, nitrogen oxides, carbon monoxide, and hydrocarbons before and after the conversion are given for the two types of source. Conversion of a major air pollution source to gas fuel would result in a reduction of the contribution of sulfur dioxide emissions of the order of 10"-"4, of particulate matter and carbon monoxide of the order of 10"-"3, and of hydrocarbons of the order of 10"-"2. The decrease will be lowest for nitrogen oxides, viz. about 40%. Analogous data for local heating sources in towns would be 10"-"5 for sulfur dioxide, 10"-"4 for particulate matter, 10"-"3 for carbon monoxide and hydrocarbons, and roughly ...
... Accession Number : ADD431225. Title : Influence of Fiber Loading on Thermal Ablation of PTFE,. Corporate Author : Personal Author(s) : Letson,KN. ...
This document is the annual update of the FFTF and Advanced Reactors Transition Program Resource Loaded Schedule for FY 2002 using current project direction and authorized funding levels
A large database (507 station-years) of daily suspended particulate matter (SPM) concentration and discharge data from 36 stations on river basins ranging from 600?km2 to 600,000?km2 in size (USA and Europe) was collected to assess the effects of SPM transport regime on bias and imprecision of flux estimates when using infrequent surveys and the discharge-weighted mean concentration method. By extracting individual SPM concentrations and corresponding discharge values from the database, sampling frequencies from 12 to 200 per year were simulated using Monte Carlo techniques. The resulting estimates of yearly SPM fluxes were compared to reference fluxes derived from the complete database. For each station and given frequency, bias was measured by the median of relative errors between estima...
The main pollutants from marine diesel engines are oxides of nitrogen (NOx), sulfur oxides (SOx) and particulates (soot). However, the proposed marine diesel engine emission regulations will primarily focus on the levels of NOx and SOx. In the future, once the proposed regulations are met, the limits and levels of other emissions will come under increasing scrutiny, such as particulates, hydrocarbons and carbon monoxide. Regardless of the type of pollutant, there are generally two classes of emission control: (1) techniques that reduce the amount of pollutant formed in the combustion process, or (2) prevent the pollutants from reaching the atmosphere. Unfortunately, some of these control techniques will not be able to meet the incoming regulations. Therefore, this paper identifies the diesel engine emissions of concern, the impending regulations, and the merits of current and future emission control technologies required to meet these ...
Protein kinase C activity has been identified in the rat brown adipocyte. About 60% of this activity is found in the cytosolic fraction under basal conditions, and 12-O-tetradecanoylphorbol 13-acetate (TPA) causes a rapid shift from the cytosol to the particulate fraction. Norepinephrine and phenylephrine causes a similar redistribution that can be blocked by prazosin but not by alprenolol. {alpha}{sub 1}-Adrenergic agonists cause three- to fivefold stimulation of type 2 iodothyronine 5{prime}-deiodinase activity in brown adipocytes. TPA has no effect on basal deiodinase activity and reduces the response of the enzyme to {alpha}{sub 1}-adrenergic agonists. These results suggest that the translocation of protein kinase C from cytosol to particulate fraction is not sufficient to increase deiodinase activity but can modulate the {alpha}{sub 1}-adrenergic agonist-mediated responses in these cells.
Abstract Smoke is a mixture of toxic gases and suspended particulate matter of solids and liquids that evolves from a fire of flammable materials. This article presents real-time consequence modeling to track the concentration of individual species in smoke as well as its soot deposition. In the modeling process presented, the burning rate or vapor mass is fed into a combustion model in which the combustion of products has been identified and quantified along with the temperature of the fire. The output of the combustion model is the smoke that will be dispersed into the ambient. The fire geometry, which depends on the type of fire (e.g., pool or flare), is identified. A dispersion model with the capability of determining particulate deposition is then used for tracking the smoke plume. Th...
Ni-Co/SiC nanocomposite coatings were electrodeposited in a modified watt type of Ni-Co bath containing 20nm SiC particles to be codeposited. Potentiodynamic polarization tests were conducted to study the effect of the SiC particulates on the electrodeposition of Ni and Co. Scanning electron microscopy was used to assess the morphology of the Ni-Co alloy and Ni-Co/SiC nanocomposite coatings. The distribution of the particulates in the matrix was considered by means of transmission electron microscopy. Applying nanomechanical testing instruments coupled to atomic force microscopy, mechanical properties of the alloy and composite coatings were studied and compared. The presence of 11vol.% SiC in the Ni-Co matrix increased hardness more than 60%. The average depth of scratch in the mentioned ...
The North Dakota Energy & Environmental Research Center (EERC) approach to removing NO{sub x} from flue gas emitted by coal-fired utility boilers or for the control of NO{sub x} formation by advanced combustion techniques involves the development of a catalytic fabric filter (CFF) for simultaneous NO{sub x} and particulate control. The NO{sub x}is removed by catalytic reduction with ammonia to form nitrogen and water. Bench-scale experimental results have shown that over 90% NO{sub x} removal can be achieved. This report details the strengths and areas for for development in this project.
The immune system modulates many key biological processes in humans. However, the exact role of the immune system in particle-associated periprosthetic osteolysis is controversial. Human tissue retrieval studies, in vivo and in vitro experiments suggest that the immune response to polymer particles is non-specific and macrophage-mediated. Lymphocytes may modulate this response. However direct lymphocyte activation by polymer particle-protein complexes seems unlikely. However, metallic byproducts may complex with serum proteins and lead to a Type IV, lymphocyte-mediated immune reaction. In predisposed individuals, this reaction may rarely lead to persistent painful joint effusions, necessitating debridement and excision of the bearing surfaces of the prosthesis. In these patients, retrieved...
Objective To evaluate the inhibitory property of de-glycyrrhizinated extract of Glycyrrhiza glabra root and its phytoconstituents (glabridin, isoliquiritigenin and glycyrrhizin) on LPS-induced production of pro-inflammatory mediators. Materials and methods Inhibitory effect of G. glabra extract and its phytoconstituents were studied on lipopolysaccharide (LPS)-induced nitric oxide (NO), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) levels in J774A.1 murine macrophages. Results G. glabra and isoliquiritigenin significantly inhibited LPS stimulated NO, IL-1 beta and IL-6 production. Glabridin showed significant inhibition of NO and IL-1 beta release, but failed to attenuate IL-6 levels at the tested concentrations. In addition, glycyrrhizin did not exhibit inhibitory response towar...
Objective: Atherosclerosis is an inflammatory disease, modulated by plaque stabilizing and de-stabilizing cell populations such as infiltrating monocytes and vascular smooth muscle cells (vSMCs). Transcription factors regulating proliferation and differentiation of atherosclerosis relevant cell types are of interest in this context. The forkhead box transcription factor FoxP1 modulates monocyte differentiation. We studied FoxP1 expression in atherosclerotic tissue, correlated FoxP1 expression with plaque characteristics and identified associations between FoxP1 and plaque proteins. Methods: 116 Atherosclerotic plaques from carotid endarterectomy samples were histologically classified (fibrous, fibroatheromatous, atheromatous) and subjected to semi-quantitative protein analysis. Macrophage,...
We hypothesize that the mushroom-derived active compound may be a potential strategy for increasing survival in response to influenza virus (H1N1) infection through the stimulation of host innate immune response. The validity of the hypothesis can be tested by immune response to influenza infection as seen through survival percentage, virus clearance, weight loss, natural killer cell cytotoxicity, Tumor Necrosis Factor-? (TNF-?) and Interferon-gamma (IFN-?) levels, lytic efficiency in the spleens of mice and inducible nitric oxide synthase mRNA expressions in RAW 264.7 murine macrophage cells. The hypothesis may improve people's quality of life, reduce the medical cost of our healthcare system and eliminate people's fears of influenza outbreak. PMID:21660092
This document describes a simple and general way to generate House Simulation Protocol (HSP)-consistent internal sensible and latent loads in unoccupied homes. It is newly updated based on recent experience, and provides instructions on how to calculate and set up the operational profiles in unoccupied homes. The document is split into two sections: how to calculate the internal load magnitude and schedule, and then what tools and methods should be used to generate those internal loads to achieve research goals.
This is a patent for a device to increase compaction of the loaded batch in a coking chamber that assures a balanced compaction of the batch from the upper to the bottom layer. The leveling rod has a device on the external end that causes the rod to shift vertically and bring pressure on the material and the pressing attachment. Opposite the loading hoppers of the coking chambers there are guides that ensure the rod will be sunk perpendicularly into the loaded material.
A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.
The present invention concerns a high thermal load heat receiving plate such as a divertor plate of a thermonuclear device. The high thermal load heat receiving plate of the present invention has a cooling performance capable of suppressing the temperature of an armour tile to less than a threshold value of the material against high thermal loads applied from plasmas. Spiral polygonal pipes are inserted in cooling pipes at a portion receiving high thermal loads in the high temperature load heat receiving plate of the present invention. Both ends of the polygonal pipes are sealed by lids. An area of the flow channel in the cooling pipes is thus reduced. Heat conductivity on the cooling surface of the cooling pipes is increased in the high thermal load heat receiving plate having such a structure. Accordingly, temperature elevation of the armour tile can be ...
The article deals with the effects of various hazardous materials in the working environment. Some of these may be detrimental to the safety and health of the worker. The absorption of hazardous substances by the human body is discussed, as well as the effects of toxic substances. The hazardous substances are classified into the following categories: irritants, asphyxiants, anaesthetics and narcotics, carcinogens, mutagens, teratogens, systemic poisons, hazardous particulate matter and the biotransformation of toxic substances. Examples of hazardous substances include: industrial solvents, fumes and vapours, lead, mercury and uranium.
This article describes the Monsanto's Indian Orchard plant gas-fired, combined-cycle cogeneration facility in Springfield, Massachusetts. The topics of the article include project configuration, the thermodynamic cycle, fuel selection, electrical distribution system, plant control, and air pollution control of NO[sub X], SO[sub 2], CO, particulates, non-methane hydrocarbons, opacity and ammonia.
A description is given of sinterable powders and methods of producing sintered products using such powders. The powders consist of (a) a particulate ceramic material, e.g. SiC, having specified particle size and surface area; (b) a carbon source material, e.g. sugar or a phenol-formaldehyde resin; and (c) a residue from a solution of H3BO3, B2O3, or mixtures of these as sintering aid. (U.K.).
BackgroundThere are several known factors that cause ischemic heart disease. However, the part played by air pollution still remains something of a mystery. Recent attention has...Full Text Available
The report summarizes the results of a dioxin/furan emissions test of a secondary copper recovery cupola furnace equipped with an afterburner for hydrocarbon emissions control and two baghouses for particulate emissions control. The cupola furnace is used...
Proper estimation of shipping emissions is essential for an impact assessment of shipping on air quality and health in port cities and coastal regions. In the Netherlands shipping is an important source of particulate matter. This report provides an internationally accessible and transparent summary and description of the methodologies used in the Netherlands Pollutant Release and Transfer Register (PRTR) to estimate PM emissions from shipping, including recently implemented updates.
A lamp system with a very soft high-intensity output is provided over a large area by water cooling a long-arc lamp inside a diffuse reflector of polytetrafluorethylene (PTFE) and titanium dioxide (TiO.sub.2) white pigment. The water is kept clean and pure by a one micron particulate filter and an activated charcoal/ultraviolet irradiation system that circulates and de-ionizes and biologically sterilizes the coolant water at all times, even when the long-arc lamp is off.
A fuel injector comprises first and second housing parts, the first housing part being located within a bore or recess formed in the second housing part, the housing parts defining therebetween an inlet chamber, a delivery chamber axially spaced from the inlet chamber, and a filtration flow path interconnecting the inlet and delivery chambers to remove particulate contaminants from the flow of fuel therebetween.
Contents: Lead smelter operations generating SO2 and particulate; Sulfuric acid plant technology; Lead smelters with sulfuric acid plant SO2 control; Sulfuric acid plant operation with lead sinter machine problems and solutions; SO2 control for ASARCO lea...
BackgroundStudies of chronic health effects due to exposures to particulate matter with aerodynamic diameters ≤ 2.5 μm (PM2.5) are often limited by sparse...Full Text Available
The present work mainly involves bench scale studies to investigate partitioning of mercury in pulverized fuel co-combustion at 1000 and 1300{sup o}C. High volatile bituminous coal is used as a reference case and chicken manure, olive residue, and B quality (demolition) wood are used as secondary fuels with 10 and 20% thermal shares. The combustion experiments are carried out in an entrained flow reactor with a fuel input of 7-8 kWth. Elemental and total gaseous mercury concentrations in the flue gas of the reactor are measured on-line, and ash is analyzed for particulate mercury along with other elemental and surface properties. Animal waste like chicken manure behaves very differently from plant waste. The higher chlorine contents of chicken manure cause higher ionic mercury concentrations whereas even with high unburnt carbon, particulate mercury reduces with increase in the chicken manure share. This might be a problem due to coarse fuel ...
This report contains data collected on a monthly basis over the period April, 1973 - April, 1975 for dustfall particulates, sodium and chloride and SO2 levels obtained from 12 monitoring sites near the Chalk Point Generating Station operated by PEPCO and ...
Pollutant emissions due to fossil fuel and biomass energy utilization in Turkey have been estimated. Standard emission factors were used for estimating the levels of particulate matter, sulfur oxides, nitrogen oxides, carbon monoxide, volatile organic compounds, and aldehydes. The results are presented for different fuels and energy-consuming sectors for the reference year 1987. Total Turkish emissions vs energy consumption are presented for every fifth year since. 1960. (author).
A billet of low-density carbon-bonded carbon fiber (CBCF) composite is machined into a desired attenuator or load element shape (usually tapering). The CBCF composite is used as a free-standing load element or, preferably, brazed to the copper, brass or aluminum components of coaxial transmission lines or microwave waveguides. A novel braze method was developed for the brazing step. The resulting attenuator and/or load devices are robust, relatively inexpensive, more easily fabricated, and have improved performance over conventional graded-coating loads.
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation of macrophage cell line with herval extracts with the treatments of recombinant interferon-{gamma} resulted in increased nitric oxide synthesis in a dose-dependent manners. In addition, ...
The long-term survival of serologically incompatible red cell units was measured in five patients with antibodies to high-frequency antigens. Initially, the survival of 1 ml of "5"1Cr-labeled incompatible red cells was measured over 1 hour. After demonstrating that the 1-hour survival times were successful (greater than 70%), each patient then received 5 ml of the same "5"1Cr-labeled red cells followed by the transfusion of the remainder of the red cell unit. The long-term T 1/2Cr survival for each case was patient 1 (anti-McCa), 15 days; patient 2 (anti-JMH), 12 days; patient 3 (anti-Kna), 31 days; patient 4 (anti-McCa), 12 days; and patient 5 (anti-Hya), 14 days. Each antibody tested in an in vitro homologous macrophage assay showed less than 5 percent phagocytosis. Anti-JMH was the only antibody to react with IgG subclass antisera and was determined to be IgG4. The macrophage assay, IgG subclass testing, and short-term (1 hour, 1 ml) "5"1Cr ...
Radiation chimeras in the early phase after bone marrow transplantation are a good model to study the efficiency of the body's nonspecific defense system represented by macrophages (M phi), polymorphonuclear cells (PMN), and NK cells. These cell types are present in large numbers in spleen and liver at that time, whereas the specific immune system represented by T and B cells is functionally deficient. We previously reported enhanced activities in vitro of M phi (and PMN) from recipient animals in an early phase after allogeneic bone marrow transfer. We here demonstrate that these activities result in enhanced spontaneous resistance against Listeria monocytogenes in vivo: CFU of L. monocytogenes in spleen and liver 48 h after infection were about 1 or 2 to 4 log steps less than in untreated control mice of donor or host haplotype. This enhanced resistance decreased over the 4-mo period after marrow transfer. Preactivated M phi were identified as the most important ...
Grid connected photovoltaic systems is one of the most promising applications of photovoltaic systems. These systems are employed in applications where utility service is already available. In this case, there is no need for battery storage because grid power may be used to supplement photovoltaic systems (PV) when the load exceeds available PV generation. The load receives electricity from both the photovoltaic array and the utility grid. In this system, the load is the total electrical energy consumption. The main objective of the present work is to optimize the electrical load pattern in Kuwait using grid connected PV systems. In this situation, the electric load demand can be satisfied from both the photovoltaic array and the utility grid. The performance of grid connected photovoltaic systems in the Kuwait climate has been evaluated. It was found that the peak ...
Some considerations regarding ice load in risk-based dam safety analysis are presented for small concrete dams. The most significant physical mechanisms leading to ice thrust on dams (such as thermal expansion and water level fluctuations) are outlined. Published literature on dam ice loads to examine ice load magnitude-return period relationships, sliding and overstressing failure mechanisms and structural performance criteria to resist ice loads, are also reviewed. Related loading combinations for structural safety evaluations were determined regarding the issue of simultaneity of ice loads with other events such as earthquakes. Parametric analyses were conducted on a small gravity dam section, 3m high, and a taller dam, 17.9 m high, to demonstrate the ultimate ice load carrying capability as a function of dam geometry and shear and ...
An effect of load conditions on Corrosion Fatigue Crack Propagation (CFCP) behavior of High Performance Steel (HPS) under seawater environment was investigated. Fatigue crack propagation tests under several load conditions including stress ratio and load frequency were conducted in air and 3.5% NaCl solution environments. Corrosion/fatigue ratio factor, C/F, particularly was defined to analyze the effect of such conditions. As shown in the results, a decrease of load ratio and frequency leads to an increase of C/F factor. Consequently, under lower loading frequency and stress ratio, the seawater condition causes much more significant effect on CFCP behavior of HPS.
Purpose Nonpoint sources (NPS) pollution has been an important cause for water quality impairment worldwide. To take the temporal variations of both NPS pollution and in-stream attenuation into consideration, an inverse modeling approach and the load duration curve (LDC) method were combined for variable nutrient total maximum daily load (TMDL) development. Methods Water quality and hydrological parameters were monitored monthly along the ChangLe River system in 2004?2008. The catchment NPS export load (EL) and TMDL for total nitrogen (TN) were estimated by the inverse format of an existing stream nutrient transport equation. The LDC method was used to describe the variability of EL, TMDL, requiring load (RLR) and percent (the ratio between the RLR and the EL, RPR) reduction, and then to s...
Research highlights: #-># The building occupancy affecting the cooling load prediction is studied. #-># PENN model is adopted in this study for predicting the building cooling load. #-># Statistical approach is adopted to result a less prejudice prediction performance. #-># Results show that occupancy data can significantly improve the prediction. -- Abstract: Building cooling load prediction is one of the key factors in the success of energy-saving measures. Many computational models available in the industry today have been developed from either forward or inverse modeling approaches. However, most of these models require extensive computer resources and involve lengthy computation. This paper discusses the use of data-driven intelligent approaches, a probabilistic entropy-based neural (PENN) model to predict the cooling load of a building. Although it is common knowledge that the presence ...
The adverse effects and diagnostic accuracy of thallium-201 myocardial SPECT after intravenous infusion of adenosine triphosphate (ATP) were studied and compared with SPECT examinations with other type of loading. The subjects of the study were 147 patients with or without coronary artery disease, who underwent some type of loading SPECT and coronary arteriography (CAG) within 30 days. Myocardial ischemia was evaluated qualitatively in SPECT and was compared with CAG for the diagnostic accuracy of coronary artery disease. The degree of myocardial uptake defect was also calculated semiquantitatively using visual scoring method and compared with coronary artery severity score. The adverse effects occurred in 46.7% of ATP loading SPECT which was more frequent that DIP loading SPECT, but all of them were transient and mild. As for the diagnostic ability the ATP loading SPECT was as ...
VACUTAINER PPT plasma preparation tubes were evaluated to determine the effects of various handling and shipping conditions on plasma human immunodeficiency virus (HIV) load determinations. Plasmas...Full Text Available
This paper presents part-load evaluation of a natural gas-fired chemical looping combustion (CLC) combined cycle with CO2 capture. The novel combined cycle employs an air-based gas turbine, a CO2-turbine and a steam turbine cycle. In this combined cycle, the CLC reactors replace combustion chamber of the gas turbine. The proposed combined cycle has a net plant efficiency of about 52.2% at full-load, including CO2 compression to 200 bar. The part-load evaluation shows that reducing the load down to 60% results in an efficiency drop of 2.6%-points. However, the plant shows better relative part-load efficiency compared to conventional combined cycles. The pressure in CLC-reduction and -oxidation reactors is balanced by airflow control, using a compressor equipped with variable guide vanes. A combination of control strategies is discussed for plant start-up and shutdown and for ...
There has been great interest in understanding the methods by which collagen-based load-bearing tissue is constructed, grown and maintained in vertebrate animals. To date, the responsibility for this...Full Text Available
In regions of high bone loading, the mechanoresponsive osteocytes inhibit osteoclastic bone resorption by producing signaling molecules. One possible candidate is matrix extracellular phosphoglycoprotein...Full Text Available
This document presented the results of a full-scale pile load tests conducted on helix pile foundations supporting power transmission towers in northern Manitoba. The site conditions were described along with pile installation and the performance of the foundations. The pile load tests were carried out in 2 different soil conditions, notably soft to firm clays and stiff high plastic clays with silt varves. The performance of the helix pile foundations were examined under axial compressive and axial tension (uplift) loading conditions. The results of the compressive load tests were presented in the form of load settlement curves while the results of the uplift load tests were presented in the form of load displacement curves. Both types of load tests in soft or stiff clays showed the suitability of helical pile ...
A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.
The association of dietary glycaemic index (GI) and glycaemic load (GL) with cardiovascular diseases has been examined in several populations with varying results. We tested the hypothesis that...Full Text Available
Jun 16, 2011 ... Results indicated that fuel loadings averaged 24.05 Mg ha 1 in 2004–2006. Forest litter decreased from wetter to drier forest life zones. ...
Thermodynamic Stable Metal Compositions for Improvement of an Operational Safety of Constructional Materials under Conditions of Multifactor Loadings of an Aggressive Environment
disciplinary methods were used to independently determine the aerodynamic loads, the thermal response, and strardural performance of the hydrogen cooled ...
PurposeThis prospective study followed 61 patients who were partially dentulous and considered to have insufficient bone volume for routine implant treatment and consequently underwent sinus inlay bone grafting.Patients and MethodsThe patients were treated with maxillary sinus floor augmentation with particulated autogenous bone from the mandibular ramus/corpus. After a healing period, dental implants (n = 180) were installed.ResultsRadiographic examination revealed average residual vertical bone heights of 6.5 mm in the first premolar region, 3.8 mm in the second premolar region, 3.5 mm in the first molar region, and 2.6 mm in the second molar region. The average implant lengths were 12 mm in the first premolar region and 11 mm in the second premolar, first, and second molar regions. All ...
Researchers at Lawrence Livermore National Laboratory are developing high-performance explosive firing vessels to contain (one time) explosive detonations that contain toxic metals and hazardous gases. The filament-wound polymer composite vessels are designed to contain up to 80 lb (TNT equivalent) explosive in a 2-meter sphere without leakage. So far, two half-scale (1-meter diameter) vessels have been tested; one up to 150% of the design explosive limit. Peak dynamic pressures in excess of 280 MPa (40 Ksi) in the vessel were calculated and measured. Results indicated that there was a small amount of gas and particle leakage past the first two of the seven o-ring seals. However, the remaining five seals prevented any transient leakage of the toxic gases and particulates out of the vessel. These results were later confirmed by visual inspection and particulate analysis of swipes taken from the sealing surfaces.
In response to the consultation from the National Council on Radiation Protection and Measurements (NCRP) to the International Commission on Radiological Protection (ICRP) committee 2, retention and excretion of 239Pu deposited at wound site were calculated by coupling together the proposed NCRP wound model and the current ICRP systemic model of Pu. The physicochemical forms considered were the soluble form categorized into 'Strong Retention', and the colloidal, particulate and fragmentary forms. The results are summarized as follows. If in soluble form, immediate medical intervention is needed to prevent uptake of radionuclides to body tissues, and prompt wound monitoring is essential for an accurate estimation of the initially deposited radioactivity. If in particulate form, a multi-component exponential equation leads to an overestimation of the absorption rate to blood because of significant lymph node drainage. The committed doses in the ...
Cell extracts of the thermophile Clostridium thermohydrosulfuricum catalyzed the phosphorylation by (..gamma..-/sup 32/P)ATP of several endogenous proteins with M/sub r/s between 13,000 and 100,000. Serine and tyrosine were the main acceptors. Distinct substrate proteins were found in the soluble (e.g., proteins p66, p63, and p53 of M/sub r/s 66,000, 63,000, and 53,000, respectively) and particulate (p76 and p30) fractions, both of which contained protein kinase and phosphatase activity. The soluble fraction suppressed the phosphorylation of particulate proteins and contained a protein kinase inhibitor. Phosphorylation of p53 was promoted by 10..mu..M fructose 1,6-bisphosphate or glucose 1,6-bisphosphate and suppressed by hexose monophosphates, whereas p30 and p13 were suppressed by 5 ..mu..M brain (but not spinach) calmodulin. Polyamines, including the odd polyamines characteristic of thermophiles, modulated the labeling of most of the ...
MoSi_2-particulate-reinforced #alpha#-SiAlON ceramic composites 10, 20, 25, and 30 vol% were prepared by at 1,750--1,800C. The #alpha#-SiAlON matrix was of the composition (Y_0_._4_8Si_1_0_._0_0Al_2_._3_0O_1_._1_7N_1_5_._2_9). The hardness for the fully dense samples changed from HV10 = 22.5 to 15.3 GPa and the toughness from 3.2 to around 5.2 MPa#centre dot#m"1"/"2 when up to 30 vol% MoSi_2 was present. Two interesting microstructural features have been found. First, with an increasing amount of MoSi_2 a pronounced coalescence of MoSi_2 particles formed a ''dual phase'' material. The second effect was the growth of elongated #alpha#-SiAlON grains in the matrix with 10 vol% MoSi_2 added. The oxidation resistance has been determined, to be unaffected by the addition of 20 vol% MoSi_2 at 1,250 C in oxygen gas of 1 atm pressure.
This report describes results from emissions testing of a prototype diesel engine, developed by Volvo Truck Corporation of Sweden, which uses pilot injection of diesel fuel for compression ignition of alcohol fuel injection for main combustion. In addition to this dual-fuel engine, emission testing was also conducted on a heavy-duty diesel engine of similar design. Both engines were tested over the 1979 13-mode FTP, or shorter versions of this modal test, and over the 1984 Transient FTP as well as an experimental bus cycle. The dual-fuel engine was characterized with methanol, ethanol and ethanol with 30 percent water (wt %). An oxidation catalyst was also used with methanol and ethanol. Emission characterization included regulated emissions (HC, CO, and NOX) along with total particulate, unburned alcohols, individual hydrocarbons, aldehydes, phenols, and odor. The particulate matter was characterized in terms of particle size distribution, ...
This work is directly to analysis of atmosphere surrounding Ipiranga Refinery; witch is located in the city of Rio Grande, in estate of Rio Grande do Sul. The refinery is surrounded by neighborhood, witch are impacted by atmospheric emissions of refinery. The objective of this work is correlating the refinery to the inhabitants that lives near the refinery, using an environmental sustainability index. This work will be achieve by analysis of Polycyclic Aromatic Hydrocarbons (PAH) bounded in particulate matter with diameter of 100 {mu}m (PTS), the acquisition of health data on the city hospitals and correlation of this data with PAH concentrations in Particulate Matter. The Samples were obtain by FEPAM, witch have three samples sites in the center of city. The samples was obtained by a High Volume Sampler equipped with quartz fiber filters. The meteorological data important to this work, like wind direction and speed, will be obtain in ...
An air conditioner intakes open-air from an open-air intake port to remove sands and sea salt particles by air filters. Then, natural and artificial radioactive particles of less than 1 {mu}m are removed by high performance particulate filters. After controlling the temperature by an air heater or an air cooler, air is sent to each of chambers in a facility under pressure elevation by a blower. In this case, glass fibers are used as the filter material for the high performance particulate filter, which has a performance of more than 99.97% for the particles of 0.3 {mu}m grain size. Since this can sufficiently remove the natural radioactive materials intruded from the outside, a detection limit value in each of the chambers of the facility can be set 10{sup -13} to 10{sup -14} {mu}ci/cm{sup 3} in respect of radiation control. Accordingly, radiation control can be conducted smoothly and appropriately. (I.N.).
This study aims to develop a particulate model combining solid waste particle combustion and heavy metal vaporization from burning particles during MSW incineration in a fluidized bed. The original approach for this model combines an asymptotic combustion model for the carbonaceous solid combustion and a shrinking core model to describe the heavy metal vaporization. A parametric study is presented. The global metal vaporization process is strongly influenced by temperature. Internal mass transfer controls the metal vaporization rate at low temperatures. At high temperatures, the chemical reactions associated with particle combustion control the metal vaporization rate. A comparison between the simulation results and experimental data obtained with a laboratory-scale fluid bed incinerator and Cd-spiked particles shows that the heavy metal vaporization is correctly predicted by the model. The predictions are better at higher temperatures because of the temperature ...
This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.
Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.
The purpose of SEADEX was to acquire a comprehensive, high-quality data base for evaluating models of dispersion within coastal zones, it secondary objective was to provide data to help determine which meteorological measurements are most appropriate for emergency preparedness at nuclear power plant sites. The study was conducted in the vicinity of Kewannee, Wisconsin, on the western shore of Lake Michigan. This report describes the design of the study and the data base resulting from it. Both a gas tracer (SF/sub 6/) and a particulate tracer (oil fog) were used. (ACR)
A catalytic trap oxidizer based on a radial flow metal mesh filter was developed for use as an after treatment device on light-duty diesel vehicles. A complete system for assisted regeneration was devised to enable this unit to operate without blocking during all normal driving modes. The integration of the catalyzed trap and regeneration system with the vehicle to provide a practical system for the reduction of diesel particulate emissions is discussed. To date, many prototype catalytic trap and regeneration system installations have been completed on various test vehicles, both naturally aspirated and turbocharged. The operational conditions and test results from a selection of these studies are presented.
Study of the rate of dissolution in simulated lung fluid of uranium from 3 different ore matrices and from refined uranium dioxide in an essentially all teflon extraction apparatus; the rate of dissolution of thorium from a nickel metal/2 percent thoria mixture; the effect of neutron irradiation of the studied materials upon the dissolution rates; and the adsorptions of the radioisotope tracers barium 133 (substitute for radium), lead 203 and thorium 234 upon the extraction system components.
Building on the concepts of MIRD methods described by Webber, Watson and others at this Symposium on the Dosimetry of Administered Radionuclides, we will now consider how to apply these principles to several experimentally based open-quote macroclose quotes and multicellular models. Specifically, methods to calculate absorbed dose using different types of particulate emission (alpha, beta) with a variety of antibody carriers (IgG, F(ab')_2, Fab) for radioimmunotherapy (RIT) will be reviewed. Additionally, a discussion of direct measurement methods at the multicellular level will reveal the problems of tumor absorbed dose heterogeneity when applied to animal and clinical studies.
Sessions covered economic and management, advance control technologies (including pulverized coal dynamic balancing-activator and control strategy by B. DeMarcy and X.Ollat), nuclear technologies, environmental (including purge considerations for seasonal SCR systems by D.P. Evely, NOx and heat rate supervisory control at NRG-Huntley operations by G Lange, comparison of gypsum dewatering technologies at flue gas desulfurization plants by B.A. Perlmutter, beta gauge particulate monitoring by J.L. Arnold), improving performance at nuclear power plants, network security, and emerging applications.
Radian Corporation was contracted to investigate duct injection and ESP phenomena in a 1.7 MW pilot plant constructed for this test program. This study was an attempt to resolve problems found in previous studies and answer remaining questions for the technology using an approach which concentrates on the fundamental mechanisms of the process. The goal of the study was to obtain a better understanding of the basic physical and chemical phenomena that control: (1) the desulfurization of flue gas by calcium-based reagent, and (2) the coupling of an existing ESP particulate collection device to the duct injection process. Process economics are being studied by others. (VC)
Radian Corporation was contracted to investigate duct injection and ESP phenomena in a 1.7 MW pilot plant constructed for this test program. This study was an attempt to resolve problems found in previous studies and answer remaining questions for the technology using an approach which concentrates on the fundamental mechanisms of the process. The goal of the study was to obtain a better understanding of the basic physical and chemical phenomena that control: (1) the desulfurization of flue gas by calcium-based reagent, and (2) the coupling of an existing ESP particulate collection device to the duct injection process. Process economics are being studied by others. (VC)
The Federal Republic of German (FRG) had uniquely strict emission legislation for particulates SO_2 and NO_X from fossil-fired power plants. The 13th Regulation to the Federal Emission Control Act required that by 1 July 1988 all large furnaces fired with solid or liquid fuels that would not be decommissioned by 1993 be retrofitted with SO_2 control technology. The emission limits are 15 per cent of the sulphur introduced with the fuel (400 mg/m"3 maximum) at thermal capacities above 300 MW. 1 ref., 9 figs, 15 bibliographies.
Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and "2"3"8Pu exciting source was used in the study of Mn, Fe, Cu, Zn, and Pb content of solid emissions, raw and final materials of a brick factory. From the point of view of metal content, the working environment if the brick factory is safe for workers. (author) 2 refs.; 2 figs.; 1 tab.
The basis of assessment for particulate exhaust emissions is the gravimetric analysis of the particle concentration of diluted exhaust gases at temperatures below 52 C. This is very time consuming and takes sufficient sensitivity at low particulate emission rates like downstream of particle filters. For this reason the C/S-method, based on the thermographic analysis of carbon and sulfur, has been developed as an alternative to the gravimetric anallysis. This method yields particle mass as well as the main particle compounds. Comparisons between both methods have been carried out for heavy duty and automobile diesel engines as well as road vehicles and large diesel engines. The tests were conducted with commercial diesel fuel and also with other fuels, such as heavy oils. It could be shown that the C/S-procedure yields the same results as the gravimetric procedure independent of engine, engine mode and kind of fuel. The analysis of all important ...
The invention concerns a method for the graduated introduction of finely-particulate and especially pulverously-particulate solid substance, in particular coal dust, from a pressurised proportioning tank containing a supply of solid matter into an industrial furnace with several supply points, in particular a shaft furnace such as a blast furnace or a cupola furnace, the solid matter being conveyed to the individual supply points in a flow of carrier gas heavily charged with solid matter, through a separate transport line for each supply point, the carrier gas being conveyed to the lower end section of the proportioning tank in a current which causes a local loosening in the lower section of the supply of solid matter, with the transport lines opening into the loosened area, whilst the proportioning tank that contains the solid matter is weighed continuously, the actual weight of the proportioning tank being compared with the latter's ...
The diagnosis of idiopathic pulmonary hemosiderosis (IPH) may be elusive. A 6-year-old boy had microcytic hypochromic anemia and a hemolytic component. Hemosiderin-laden macrophages were not found in the gastric aspirate. He had no pulmonary signs or symptoms. Extensive hematologic and roentgenologic investigations failed to reveal the cause of the anemia. Quantitative serial scintigraphic scanning showed significant (35%) pulmonary sequestration of autologous erythrocytes labeled with sodium chromate Cr51. The half-life of the RBCs was moderately decreased (half-life, 15 days; normal, 25 to 35 days). An open-lung biopsy spece Cr51. The half-life of the RBCs was moderately decreased (half-life, 15 days; normal, 25 to 35 days). An open-lung biopsy specimen confirmed the diagnosis of IPH. A diagnosis of IPH should be considered when children have iron deficiency anemia and pulmonary signs or symptoms. Organ sequestration studies may be helpful in equivocal cases.
Cholestatic liver injury induced by alpha-naphthylisothiocyanate (ANIT) is provoked by injury to intrahepatic bile ducts and the progression of hepatic necrosis requires the procoagulant protein tissue factor (TF) and extrahepatic cells including neutrophils. Recent studies have shown that myeloid cell TF contributes to neutrophil activation. We tested the hypothesis that myeloid cell TF contributes to neutrophil activation in ANIT-treated mice. TF activity in liver homogenates increased significantly in TF^f^l^o^x^/^f^l^o^x mice treated with ANIT, but not in TF^f^l^o^x^/^f^l^o^x/LysMCre mice (TFD^M^y^e^l^o^i^d mice), which have reduced TF expression in monocytes/macrophages and neutrophils. Myeloid cell-specific TF deficiency did not alter expression of the chemokines KC or MIP-2 but redu...
Patients with acquired immunodeficiency syndrome (AIDS) are subject to a spectrum of central nervous system (CNS) disorders. Recent evidence implicates the human T-cell lymphotropic virus type III (HTLV-III) in the pathogenesis of some of these illnesses, although the cells infected by the virus have yet to be identified. Using in situ hybridization, the authors examined brain tissue from two patients with AIDS encephalopathy for the presence of HTLV-III RNA. In both cases, viral RNA was detected and concentrated in, though not limited to, the white matter. The CNS cells most frequently infected included macrophages, pleomorphic microglia, and multinucleated giant cells. Less frequently, cells morphologically consistent with astrocytes, oligodendroglia, and rarely neurons were also infected. The findings strengthen the association of HTLV-III with the pathogenesis of AIDS encephalopathy. In situ hybridization can be applied to routinely prepared biopsy tissue in ...
Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to #beta#_2 subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasma membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP) fused ...
A device is described for transporting loads, especially for moving belt driving stations in open pit mining operations with a propelling mechanism which for lifting a respective load is operable to move into a free space formed by the load with the ground. The device comprises a plurality of lifting mechanisms, by means of which, a lifting platform can be brought into engagement with a supporting surface of the load. The device comprises at least one supporting member which is so designed that it prevents the lifting platform from lifting off lifting mechanisms. Furthermore, means are provided which permit a turning of the lifting platform relative to the lifting mechanisms about a vertical axis which is arranged in a certain relationship to the propelling mechanism.
Background, aim, and scope Semi-trailers with load boxes are the most important mode of grain transport by land in the world. Load boxes can be produced with different materials such as: wood, steel, and synthetic material. They are responsible for effectiveness retention and quality of grains during the transport. Among the main aspects to be considered and valued when selecting materials for load boxes are the final mass of the semi-trailer, loss of grains, and mechanical properties. Environmental performance is another important aspect to be taken into account for developing and selecting new materials in this kind of application. This study presents a comparative environmental evaluation of load boxes built from two different materials (a wood panel and a three-layer synthetic (TLS) pa...
Experimental results of quasi-static and dynamic fracture of particle-filled polymer composite (PFPCM) "ALTUGLAS EI CH25" with a matrix of polymethylmethacrylate (PMMA) are reported in this paper. PMMA matrix is filled with rubber particles, as result a shock-resistant transparent composite is produced. The main task was to investigate experimentally and theoretically the fracture toughness of this composite under static and dynamic loading. A high-rate loading has been created by impulse magnetic field. Analysis of fracture process and its relation with the load parameters and material microstructure have been established. Application of the original testing method enabled determination of fracture toughness at very short loading times and comparison of the results with material dynamic p...
This paper introduces the summary of design guideline (draft) for the limit state design method for foundation structures, and examples of calculations on pile foundations. The limit states were set using the load to transformation curves, and the limit state No. 3 in particular assumed a large earthquake, a state that a foundation is fatally damaged because of rarely acting loads that lead to generation of displacement and loss of stability and functions. Ground survey coefficient, ground resistance coefficient, and ground property coefficient were defined especially as the safety coefficients. With respect to the displacement in the limit state No. 3, a restriction value was set for the plasticity of the foundation. Loads were given considerations of combination of permanent load, variation load, and accidental load, each having been set with a ...
Accurately predicting wind turbine blade loads and response is important for the proper design of wind turbines. The need to accurately predict both deterministic and stochastic blade loads is now widely recognized. Previous rotor code development and validation efforts at NREL have concentrated on prediction of deterministic and stochastic blade loads for rigid hub rotors. During the past year this effort was expanded for predicting blade and shaft loads for two-bladed teetering hub rotors. The NREL (formerly SERI) Teetering Rotor Analysis Program (STRAP), a derivative of the Force and Loads Analysis Program (FLAP), can include the effects of rotor undersling, delta-3 and the effects of a concentrated hub mass. The degrees of freedom include rotor teeter and symmetric and asymmetric rotor flap modes. A time-dependent, prescribed yaw motion can also be input to the code. ...
Taiheiyo coal deashed using acid treatment and loaded with potassium or calcium was hydro-cracked under gaseous phase to discuss effects of these metals on liquefaction reaction. In addition, the loaded coal was added with red mud catalyst to examine effects of the addition. The loaded potassium has a softening power, and particularly the potassium adsorbed into surface and micropores in the coal decomposes selectively HI-BS and BI-PS and generates gas and HS. On the other hand, potassium deposited on coal surface promotes direct gas production from the coal. Irrespective of its loading modes, calcium has a catalytic nature to produce HI-BS selectively. Calcium also acts to impede decomposition of HI-BS into HS. Adding red mud catalyst to potassium loaded coal increases the inversion rate and the liquefaction yield, and most of the increase is accounted for by HI -BS, and BI-PS. ...
A 25m wind turbine blade was tested to failure when subjected to a flapwise load. With the test setup, it was possible to test the blade to failure at three diffe-rent locations. The objective of these tests is to learn about how a wind turbine blade fails when exposed to a large flapwise load and how failures propagate. The report shows also results from ultra sonic scan of the surface of the blade and it is seen to be very useful for the detection of defects, especially in the layer between the skin laminate and the load carrying main spar. Acoustic emission was successfully used as sensor for the detection of damages in the blade during the test. The report contains measurements of the total deflection of the blade, the local deflection of the skin and the load carrying main spar and also measurement of strain all as a function of the applied load and up to failure of the blade. ...
The solubilities of plutonium and uranium have been determined for alkaline salt solutions having compositions which bound those which will be processed in the In-Tank Precipitation (ITP) process. Loadings of plutonium and uranium onto monosodium titanate (MST) have been determined at temperatures bounding those expected to occur during ITP and using a salt solution which was determined to have the maximum solubility for uranium and plutonium. Fissile loadings increase with decreasing amounts of MST in contact with the salt solutions saturated in plutonium and uranium. At MST concentrations bounding those which are planned for the ITP process, expressions for the maximum loadings (wt %) are determined to be 0.29 - 0.20x[MST] for plutonium and 1.8 - 0.29x[MST] for uranium, where [MST] is the concentration of MST in grams/liter. These expressions are valid over the range of MST concentrations from 0.05 to 0.51 g/L and ...
The thermal contact resistance between balls and inner and outer rings of thermally steady space-use deep groove ball bearings was studied experimentally to verify the validity of the previously proposed calculation method for the resistance. The 440C stainless steel single row bearing was used for measuring its steady state temperature distributions in a vacuum environment under axial, radial and combined load conditions. As a result, the experimental results of the resistance well agreed with calculated ones under each load condition resulting in the sufficient validity at nearly the same surface roughness. It was necessary to apply a static equivalent radial load to calculation under the combined load that a contact angle is larger than the angle of resultant force dependent on both load components. In experiments under only radial load, measurement of outer ...
The objective of the study was to investigate neuronal processing during the encoding, retention and retrieval phases of a serial visual working memory task. Particularly, we were interested in how these phases are affected by working memory load and how processing is modulated by methylphenidate. Healthy adults were asked to memorize the order of four, five or six pictures under methylphenidate (20mg) and under placebo while brain electrical activity was recorded. On the performance level, the number of correct responses decreased with increasing working memory load. Concerning brain electrical activity, in the encoding phase P3 amplitudes increased at midline electrodes with increasing memory load while load had no effect in the retention and retrieval phase. Medication neither influenced performance nor the different processing stages significantly. Our data provide evidence that during the encoding ...
An experimental apparatus has been built that allows direct measurement of the oil film thickness in a bearing that is subjected to dynamic loads and shaft speeds representative of those occurring in automotive engine connecting rod, big-end bearings. Dynamic motion of the shaft, relative to the bearing, is measured as a function of shaft rotational angle, using non-contact, eddy-current probes. A computer based data acquisition system is used to measure, record, and analyze the journal position in the bearing. The test bearing is 63.5 mm in diameter by 25.4 mm long, and is loaded using a servo-hydraulic actuator rated at 98.3 kN. The journal has an operating speed of 500 to 3800 rpm. The actuator is controlled by a computer-generated waveform that can duplicate load profiles developed by various engines operating at a wide range of conditions. Measurements taken with the shaft statically loaded show ...
Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed to evaluate gear fault advancement quantitatively. We found that this parameter is insensitive to varying load and ...
This paper presents a systematic approach to the automatic determination of the evolution of the rigid-plastic structural response caused by a proportional or single parameter pressure loading which varies with time in a monotonic non decreasing fashion. The frame structure is envisaged as a network, and the fundamental vectorial conditions characterising its behaviour at any instant of time are combined in a consistent manner. By considering the level of the pressure loading to be a single load parameter ranging monotonically from zero to infinity, the structural governing system may be regarded as a parametric linear complementary problem. (author). 13 refs., 2 figs.
The load-carrying capacity and ultimate deformation capacity of timber-concrete composite systems can be significantly influenced by the ductility of the connection between the two materials. The use of more ductile connections can increase the load-carrying capacity of the composite system as well as its ultimate deformation capacity. In this work, the potential increase that might be expected for these two parameters due to the use of ductile connections will be assessed through numerical simulations, taking the non-linear behaviour of the connections into account. Furthermore, the connection ductility required to achieve the maximum load capacity depends on the mechanical properties of the connection as well as on the geometric and mechanical properties of the composite system. There ar...
ABS>A horizontal steam generator design for the SM-2 was lysis to determine the per formance of such a steam generator under steady state operating conditions and during load transients, The configuration for this design is a two- drum unit consisting of a heat exchanger unit and separator drum interconnected by integral riser and downcomer. An analog computer was used to analyze the steam generator behavior Wring load transients. The effect of various design changes on the response of the steam generator to step chages in load was determined. The horizontal steam generator design was compared to the existing vertical steam generator design for weight, size, price, and performance. (auth)
A study was conducted on diesel engines to find out the effect of induction rate of biogas on engine performance indices. The results of dual fuel engine performance was compared with diesel mode for various levels of biogas induction rate (0.3 to 7.2 l/s) engine load (20% to full load) and injection timing (20.6 to 48 before top dead centre). At full and 80% brake load, the best energy mix between diesel and biogas was 1.5:1 and 4:1 respectively. (author). 7 refs., 7 figs., 4 tabs.
Long crack fatigue threshold ({delta} K{sub th}) and crack closure behaviour of two thermomechanically processed microalloyed (MA) ferrite-pearlite steels are reported. {delta} K{sub th} and crack closure were measured using a dynamic compliance measurement technique. Crack closure was observed at low load ratios (R < 0.5) and the fatigue thresholds decreased with increasing load ratio. In both steels, the closure-free intrinsic threshold ({delta} K{sub eff} {sub th}) was found to be independent of the load ratio. (orig.)
Several types of X-band high power loads developed for several tens of MW range were designed, fabricated and used for high power tests at X-band facility of KEK. Some of them have been used for many years and few units showed possible deterioration of RF performance. Recently revised-design loads were made by CERN and the high power evaluation was performed at KEK. In this paper, the main requirements are recalled, together with the design features. The high power test results are analysed and presented
The effect of additives on the grafting of a monomer, butylmethacrylate (BA), into simul (a soft wood) has been studied using {sup 60}Co source at 3 Mrad. The enhancement of polymer loading (grafting) by the addition of minute amounts (1%) of oligomers and of polyfunctional monomers into simul + BA system has been further increased in the presence of acid and urea. The synergistic polymer loading yields by acid addition cause substantial decrease of tensile strength values of wood-plastic composite; but urea increases both polymer loading and tensile strength values synergistically in these systems. (author).
The effect of additives on the grafting of a monomer, butylmethacrylate (BA), into simul (a soft wood) has been studied using "6"0Co source at 3 Mrad. The enhancement of polymer loading (grafting) by the addition of minute amounts (1%) of oligomers and of polyfunctional monomers into simul + BA system has been further increased in the presence of acid and urea. The synergistic polymer loading yields by acid addition cause substantial decrease of tensile strength values of wood-plastic composite; but urea increases both polymer loading and tensile strength values synergistically in these systems. (author).
An aspiration cover is proposed for the site of loading a belt conveyer including a housing arranged above the belt conveyer in whose cover there is an aspiration sleeve and a discharge chute from the upper wall and a guide having a cushioning plate on the lower end. It is distinguished by the fact that in order to improve the effectiveness of removing dust by decreasing the volume of aspirated air, the cover between the aspiration sleeve and the upper wall of the loading chute is convex in the inside of the housing and has a smooth connection to the upper wall of the discharge chute turned towards the cushioning plate.
The non linear electrical loads can give rise to a number of disturbances in electrical power networks. Among them, the high consumption of relative power is to be noted and so is the several harmonic components which may be injected in the industry system and very often in the utility system. So, by using appropriate technical considerations, as well as measurements in typical special electrical loads, such negative effects are analyzed and ways of minimizing them are suggested. (author) 3 refs., 11 figs., 6 tabs.
The problem of pile groups subjected to lateral loads is of interest particularly in offshore and coastal regions. An understanding of pile-soil interaction is essential in designing such pile foundations. In this paper, a simplified finite element analysis in conjunction with Yegian and Wright approach has been presented to study the behavior of pile groups under lateral loads. The pile is treated as a shear beam and the soil media is assumed to be linear elastic. The results of the analysis are used to estimate: (1) Lateral Group Efficiency and (2) Extent of stress influence around the pile. The results obtained from the theoretical predictions are found to be reasonably in good agreement with the published literature.
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe{sup 3+} and Fe{sup 2+}) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe"3"+ and Fe"2"+) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
This paper presents a detailed characterization and rheometric property study of in-situ sodium activated, organomodified bentonite clay - styrene-butadiene rubber (SBR) nanocomposite. It was found that around 10phr loading was the optimum level for maximum effect of the organo clay. The WAXD data indicated that at higher loading there was formation of agglomerations in the matrix. It was found that organo clay compound exhibited lower maximum torque in comparison to equivalent amount of carbon black loaded compound. The nanocomposites were also used for partial replacement of N330 carbon black in a highly black loaded compound. Part replacement of the carbon black with nano-clay reduced the maximum rheometric torque in comparison to the control compound. Detail study revealed that with sl...
Wood-polymer composites (WPC) have been prepared of pinewood with different monomers using Gamma radiation: acrylamide, butyl acrylate, butyl methacrylate, styrene, acrylonitrile, and polyester. The polymer loading was determined as a function of monomer concentration and absorbed dose. The data show that polymer loading increases by increasing the monomer concentration. In two cases, BMA and polyester, the polymer loading decreases at high concentrations. This can be explained by the increase of the viscosity. Thus the diffusion of the compound into bulk would be slower. The absorbed dose seems to play a positive role in enhancing the polymer loading by increasing the dose. The mechanical properties, tensile and compression strength, have been improved in the most cases for all monomer concentrations or absorbed doses. Using polyester there was no improvement in the mechanical properties, and using ...
This paper presents a dynamic displacement influence line method for moving load identification on bridge. The finite element model of Poyang Lake continuous truss bridge-train systems is established and the dispersed modal shapes are acquired by modal analysis. Multi-axle moving train loads are identified with simulated annealing genetic algorithm by minimizing the errors between the measured displacements and the reconstructed displacements from the identified moving loads. In the identification process, the dynamic displacement influence line technique is used to calculate the time history displacement responses of the bridge to avoid solving equations of motion of the bridge repetitively. Several important parameters of the bridge-train system are discussed to investigate their effects...
A method for determining the rational capacity of the shield supports under various geological conditions is proposed. Based on the instrumentation of the pressure histories of the shield legs in eight mines, the relation between the final load or the increment of support resistance in a mining cycle and the setting load is established. The relation is represented by a mathematical equation with characteristic constants. Those constants are related to the physical properties of the immediate and main roof strata. Nomographs were constructed for determining the constants under various geological conditions. The paper discusses the principles and step-by-step procedures for determining the rational setting and yield loads for all the shield supports employed in the eight mines. The predicted values are then compared with the actual ones used by the operators. 7 refs., 6 figs., 4 tabs.
This paper describes Automatic Refueling Planning System (ARPS) for a nuclear power station using Genetic Algorithms (GA) and a Simulated Annealing (SA). ARPS has been developed and verified by applying to the Fugen nuclear power station (NPS), which is a 165MWe, heavy water-moderated, boiling light water-cooled, pressure tube-type reactor developed by JNC utilizing mainly uranium and plutonium mixed oxide (MOX) fuel. Fuel loading patterns have been managed independently in the Fugen NPS since the initial core. A planning of an adequate fuel loading pattern on each operational cycle needs one to two months even for expert core management engineers, for the reason that it has multi-objective optimization and nonlinear problems. In order to achieve the optimum fuel loading pattern and a fuel cost reduction, ARPS has been developed by JNC and CRC Solutions Corporation for the last five years. ARPS firstly generates several ...
The load-following operation of nuclear power plants will become inevitable due to the increased nuclear share in the total electricity generation. As a groundwork for the load-following capability of the Korean next generation PWRs, the state-of-the-art has been reviewed. The core control principles and methods are the main subject in this review as well as the impact of load-following operations on the fuel performance and on the mechanical integrity of components. To begin with, it was described what the load-following operation is and in what view point the technology should be reviewed. Afterwards the load-following method, performance and problems in domestic 900 MWe class PWRs were discussed, and domestic R and D works were summarized. Foreign technologies were also reviewed. They include Mode G and Mode X of Foratom, D and L bank method of KWU, the method using PSCEA of ...
High-energy synchrotron x-ray diffraction (XRD) has been used to quantify load transfer in bovine plexiform bone. By using both wide-angle and small-angle XRD, strains in the mineral as well as the collagen phase of bone were measured as a function of applied compressive stress. We suggest that a greater proportion of the load is borne by the more mineralized woven bone than the lamellar bone as the applied stress increases. With a further increase in stress, load is shed back to the lamellar regions until macroscopic failure occurs. The reported data fit well with reported mechanisms of microdamage accumulation in bovine plexiform bone.
0pen ended piles develop internal frictional resistance between the internal soil plug end the pile wall during axial loading. Current pipe pile design practice assumes that the ultimate internal skin friction is of the same order of magnitude as the outer skin friction. This paper describes a series of laboratory pile load tests on instrumented model pipe piles, designed to investigate the development of plug stresses and skin friction along the plug length during pile loading. The piles contain sand columns of various relative densities and of different heights. The soil plugs are loaded to failure under fully drained conditions. The test data indicate that internal skin friction in sand can be substantially higher than assumed in conventional design practice. This finding could lead to significant economical savings on future pipe pile foundations in sand.
The fatigue and fracture behavior of hard tissues are topics of considerable interest today. This special group of organic materials comprises the highly mineralized and load-bearing tissues...Full Text Available
The nucleation of microdamage under dynamic loading was investigated through planar impact experiments accomplished with a light gas gun. The microscopic observation of recovered and sectioned specimens showed that microcracks were nucleated only by cracking of brittle particles inside material. However, for comparison the in situ static tensile tests on the same material conducted with a scanning electron microscope showed that the microcracks were nucleated by many forms those were fracture of ductile matrix, debonding particles from matrix and cracking of brittle particles. The quantitative metallographic observations of the specimens subjected to impact loading showed that most of the cracked particles were situated on grain boundaries of the aluminum matrix. These facts suggested the concept of critical size and incubation time of submicroscopic cavities in the dynamic case and the mechanism of embryo-damage induced nucleation by fracture ...
Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires the determination of the effective thermal conductivity as well as the thermal contact resistance between the GDL and adjacent surfaces/layers. The Part 1 companion paper describes an experimental procedure and a test bed devised to allow separation of the effective thermal conductivity and thermal contact resistance, and presents measurements under a range of static compressive loads. In practice, during operation of a fuel cell stack, the compressive load on the GDL changes. In the present study, experiments are performed on Toray carbon papers with 78% porosity and 5% PTFE under a cyclic compressive load. Results show a significant hy...
... In fact, for dynamic loading, the ultimate compressive strength can be more than doubled (Bischoff and Perry 1991), whereas the ultimate uniaxial ...
;Table of Contents: Legal authority; Summary of proposed regulations; Industry definition and waste streams; Industry description; Data and information gathering; Selection of pollutant parameters; Drilling wastes-characterization, control, and treatment technologies; Produced water-characterization, control, and treatment technologies; Miscellaneous waste-characterization, control, and treatment technologies; Cost and pollutant loading determination of drilling fluids and drill cuttings; Compliance cost and pollutant load determination of produced water; Compliance cost and pollutant load determination of well treatment, workover, and completion fluids; Cost and pollutant loading determination of deck drainage; Options selection-rationale and total costs; Pretreatment standards; Non-water quality environmental impacts and other factors; Best Management Practices; and Appendices.
Background Photopolymerizable poly(ethylene glycol) (PEG) hydrogels offer a platform to deliver cells in vivo and support three-dimensional cell culture but should be designed to degrade in sync with neotissue development and endure the physiologic environment. Questions/purposes We asked whether (1) incorporation of degradation into PEG hydrogels facilitates tissue development comprised of essential cartilage macromolecules; (2) with early loading before pericellular matrix formation, the duration of load affects matrix production; and (3) dynamic loading in general influences macroscopic tissue development. Methods Primary bovine chondrocytes were encapsulated in hydrogels (n?=?3 for each condition). The independent variables were hydrogel degradation (nondegrading PEG and degrading olig...
... being designed for projected Minotaur IV launch load environments, with design objectives of light weight, integrated vibration isolation, low shock ...
Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed ...
This paper presents a design of fuzzy power system stabilizer (FPSS) using adaptive evolutionary computation (AEC). We have proposed an adaptive evolutionary algorithm which uses a genetic algorithm (GA) and an evolution strategy (ES) in an adaptive manner in order to take merits of two different evolutionary computations. FPSS shows better control performances than conventional power system stabilizer (CPSS) in three-phase fault with heavy load which is used when tuning FPSS. To show there robustness of the proposed FPSS, it is applied to damp the low frequency oscillations caused by disturbances such as three-phase fault with normal and light load, the angle deviation of generator with normal and light load and the angle deviation of generator with heavy load. Proposed FPSS shows better robustness than CPSS. (author). 15 refs., 13 figs., 3 tabs.
During the first and second quarters of 1994 air samples were collected and analyzed from 54 air particulate/halogen sampling stations, 10 noble gas sampling stations and 19 tritiated water vapor sampling stations. Surface water samples were collected and analyzed from 12 open water supply reservoirs, 8 natural springs, 2 wastewater containment ponds and 9 sewage lagoons. Groundwater samples were obtained brom 10 potable and 1 non-potable supply wells, and 8 drinking water consumption points. Ambient radiation levels were measured at 193 locations.
Diesel passenger car is superior to gasoline engine car in the fuel economy, but it has some defects to improve: noise, startability, particulate and transient performance, etc. Among these problems, this paper presents particularly transient performance in a diesel engine and clarifies the causes of its decline at lower temperature operation. As the results, it is found that the transient torque at the early stage of acceleration is only 50% at -20/sup 0/C, and that when coolant temperature went up to 20/sup 0/C, the transient torque approaches to that of the warmed up engine. The transient response become worse with retarding the injection timing and with decreasing the engine speed. On the other hand, since the normal response is not obtained despite using high cetane number fuel, main cause of the inferior transient torque is not the poor combustion, but the increase of friction or cooling loss.
High energy physics is a basic research domain with a well established European and international cooperation. Cooperation can be of different type depending on the size of the facilities involved (accelerators), on their financing, and on the type of experiments that use these facilities. The CERN, the European center for nuclear research, created in October 1954, is the best example of such a cooperation. This article examines first the juridical and scientifical structure of the CERN and the mode of organization of big experiments. Then, it presents the role of international committees in the establishment of a common scientific policy in Europe and in the rest of the world. Finally, the possible future evolution of the CERN towards a worldwide project is evoked. (J.S.)
The conference was organized to bring together scientific and business people from Canada, United States, and Mexico to foster the protection and improvement of the environment and to promote sustainable development in the three NAFTA countries. The sessions are international cooperation and partnerships (panel discussion), markets, market access, economic instruments, venture and capital growth, economic instruments versus regulations, international financial institutions, partnerships and networks, government support programs (panel), acid rain, stratospheric ozone, smog and ground level ozone, innovative measurement methods, hazardous air pollutants, respirable fine particulates, climate change prevention technologies, pollution prevention technologies, indoor air technology, and posters. Selected papers have been abstracted separately.
The age hardening behavior of Al-4.5%Cu alloy composite reinforced with zircon sand particulates and produced by stir casting route has been investigated in different quenching media viz, water, oil, and salt brine solution (7wt%). Optical microscopy of the as cast alloy composite indicates that the matrix of the composite has the cellular structure. Copper rich CuAl2 precipitates have been found near particle matrix interface. The results of ageing demonstrate that the microhardness of age hardenable Al-Cu based alloy composites depend on the quenching medium in which they are heat treated. Salt brine quenching is faster as compared to water and oil, even if higher strength is obtained but cannot be used for complex shapes and thin sections where oil quenching is the alternative due to mi...
Results of discrete element method (DEM) simulation and magnetic resonance imaging (MRI) experiments are compared for monodisperse granular materials flowing in a half-filled horizontal rotating cylinder. Because opacity is not a problem for MRI, a long cylinder with an aspect ratio {approximately}7 was used and the flow in a thin transverse slice near the center was studied. The particles were mustard seeds and the ratio of cylinder diameter to particle diameter was approximately 50. The parameters compared were dynamic angle of repose, velocity field in a plane perpendicular to the cylinder axis, and velocity fluctuations at rotation rates up to 30 rpm. The agreement between DEM and MRI was good when the friction coefficient and nonsphericity were adjusted in the simulation for the best fit. {copyright} {ital 1998 American Institute of Physics.}
Mechanistic studies on a charged ultrafiltration (UF) membrane fouled with natural organic matter (NOM) and colloidal particles are systematically investigated to understand the relative role of each NOM fraction and the presence of colloidal particulate to membrane fouling. Humic acid (HA), dextran, and kaolin were employed as surrogate model foulants representing the organic hydrophobic acid NOM, hydrophilic neutral NOM, and inorganic colloidal materials, respectively. The results obtained showed that the organic NOM of hydrophilic surrogate (dextran) plays a primary role in promoting membrane fouling, followed by hydrophobic acids and inorganic kaolin, but to a lesser extent than organic NOM compounds. Significant differences in the extent of fouling between dextran and HA have been obs...
Radiological and environmental protection experience associated with the reactor cover gas processing system at the Fast Flux Test Facility (FFTF) has been excellent. Personnel radiation exposures received from operating and maintaining the reactor cover gas processing system have been very low, the system has remained free of radioactive particulate contamination through the first seven operating cycles (cesium contamination was detected at the end of Cycle 8A), and releases of radioactivity to the environment have been very low, well below environmental standards. This report discusses these three aspects of fast reactor cover gas purification over the first eight operating cycles of the FFTF (a duration of a little more than four years, from April 1982 through July 1986).
The changed political situation and recognition of the acute destruction of the natural environment in Poland have caused a series of actions aimed at preventing further deterioration of Polish environment. One of the most important events which took place in the last few years was the enactment by the Polish Parliament in May 1991 of the Act on the National Ecological Policy. The basic assumption of the new environmental policy is a declaration that sustainable development will in future direct economic development in Poland. The aim of the presented paper is to introduce existing policy of air protection and instruments which have been implemented to protect the air. Special attention is paid to legislation instruments, introduction and enforcement of proper economic mechanisms strengthening air protection and foreign policy aiming at increasing foreign assistance for this objective. Pollutants involved include sulfur dioxide, nitrogen oxides, carbon dioxide and ...
SUMMARY We construct a new class of granular landslide models in which avalanches are simulated with large numbers of independent particles moving under the influence of topographically derived gravitational and centripetal acceleration. Concurrently, the particles suffer deceleration due to basal and dynamic friction. The novel aspect of the calculation is that complex particle-to-particle interactions, fluctuating basal contacts, and unresolved topographic roughness within and below the deforming flow are mimicked by random perturbations in along-track and cross-slope acceleration. We apply the method to the 1980 May 18 Mount Saint Helens debris avalanche by constraining the initial geometry and structure of the slide mass from geological data, and the initial failure sequence from eyewi...
Twelve powders of TiO_2-Y_2O_3-ZrO_2 solid solution of the methodically changed composition were prepared by a coprecipitation-calcination technique. After mixing with phenol-formaldehyde resin, the powders were calcinated for 2 hours at 1200"oC in vacuum. The resultant composite powders contained TiC and non-reacted carbon. Green compacts were sintered in vacuum at 1500"oC for 2 hours. A temperature increase was stopped at 1200"oC to react remains of carbon. There were two carbides in the composites TiC and ZrC. TiC non-stoichiometry depended on carbon content in the system. Phase composition of the depended on of titania and yttria in zirconia solid solution. The majority of the samples showed two tetragonal zirconia phases differing in lattice parameter and tetragonality. (author)
ResumeLa convergence des solutions faibles du systeme de Navier-Stokes-Fourier-Poisson compressible avec un terme de frottement est etudiee dans la limite dun frottement infini, la loi de pression incluant, comme cas particulier, celle correspondant aux particules de Fermi-Dirac. La limite se trouve etre une solution faible dun systeme de Smoluchowski-Poisson non isotherme, la temperature ne dependant que de la variable temporelle et etant determinee par la conservation de lenergie totale.
A microcosm laboratory experiment was conducted to determine the impact of biological reworking by the ragworm Nereis diversicolor on the redistribution of particle-bound radionuclides deposited at the sediment-water interface. Over the course of the 40-day experiment, as much as 35% of a 137Cs-labelled particulate tracer deposited on the sediment surface was redistributed to depths of up to 11 cm by the polychaete. Three different reworking models were employed to model the profiles and quantify the biodiffusion and biotransport coefficients: a gallery-diffuser model, a continuous sub-surface egestion model and a biodiffusion model. Although the biodiffusion coefficients obtained for each model were quite similar, the continuous sub-surface egestion model provided the best fit to the data...
Optimization of nonviral gene delivery typically focuses on the design of particulate carriers that are endowed with desirable membrane targeting, internalization, and endosomal escape properties. Topographical control of cell transfectability, however, remains a largely unexplored parameter. Emerging literature has highlighted the influence of cell-topography interactions on modulation of many cell phenotypes, including protein expression and cytoskeletal behaviors implicated in endocytosis. Using high-throughput screening of primary human dermal fibroblasts cultured on a combinatorial library of microscale topographies, we have demonstrated an improvement in nonviral transfection efficiency for cells cultured on dense micropit patterns compared to smooth substrates, as verified with flow...
In June 2003, we conducted a two-part field exercise to examine biogeochemical characteristics of water in the lower Mississippi river during the 4 days prior to discharge and in the Mississippi river plume over 2 days after discharge. Here we describe the fates of materials immediately after their discharge through Southwest Pass of the Mississippi delta into the northern Gulf of Mexico. Changes in surface water properties immediately after discharge were much larger and more rapid than changes prior to discharge. Total suspended matter (TSM) declined, probably due to sinking, dissolved macronutrients were rapidly diminished by mixing and biological uptake, and phytoplankton populations increased dramatically, and then declined. This decline appeared to begin at salinities of approximatel...
The 'KUPOLOPT' joint research project has as its target the economic and ecological optimization of cupola furnaces in foundries. The use of natural gas/oxygen burners during foundry operation is being studied on Fritz Winter Eisengiesserei GmbH and Co. KG's cupola furnace with the objective of enhancing melting rate, reducing emissions and permitting re-utilization of foundry and other particulates. This work is also intended to improve the cupola-furnace process in economic terms, in order to enhance its competitiveness. This article presents the results of the first project phase, which served to investigate the natural gas/oxygen burner as an external supplier of energy. (orig.)
Environmental data were collected for most environmental media including air, Columbia River water, external radiation, foodstuffs (milk, beef, eggs, poultry, and produce) and wildlife (deer, fish, and game birds), as well as soil and vegetation samples. In general, offsite levels of radionuclides attributable to Hanford operations during 1979 were indistinguishable from background levels. The data are summarized in the following highlights. Air quality measurements of NO/sub 2/ in the vicinity of the Hanford Site and releases of SO/sub 2/ onsite were well within the applicable federal and state standards. Particulate air concentrations exceed the standards primarily because of agricultural activities in the area. Discharges of waste water from Hanford facilities in the Columbia River under the National Pollution Discharge Elimination System (NPDES) permit were all within the parameter limits on the permit.
Los Alamos National Laboratory (the Laboratory) is subject to emissions reporting requirements for regulated air contaminants under Title 20 of the New Mexico Administrative Code, Chapter 2, Part 73 (20 NMAC 2.73), Notice of Intent and Emissions Inventory Requirements. The Laboratory has the potential to emit 100 tons per year of suspended particulate matter, nitrogen oxides, carbon monoxide, sulfur oxides, and volatile organic compounds. For 1998, combustion products from the industrial sources contributed the greatest amount of criteria air pollutants from the Laboratory. Research and development activities contributed the greatest amount of volatile organic compounds. Emissions of beryllium and aluminum were reported for activities permitted under 20 NMAC 2.72 Construction Permits.
Objectives1. We will use reduction of lysosomal stability as an indicator of cell injury induced by C-60 fullerenes and carbon nanotubes in the liver analogue or digestive gland (hepatopancreas) of marine mussels. Molluscan hepatopancreatic digestive cells are key to normal function and are a sensitive key interface with the environment. Reduction of lysosomal stability is mechanistically linked with impaired health of the whole animal. 2. We will also test the hepatopancreatic digestive cells for evide [continued...]DescriptionNanotechnology is a major innovative scientific and economic growth area, which may present a variety of hazards for environmental and human health. The surface properties and very small size of nanoparticles and nanotubes provides surfaces that may bind and transport toxic chemical pollutants, as well as possibly being toxic in their own right by generating reactive oxygen species (ROS). There is a wealth of evidence for the harmful effects of nanoscale ...
The performance of different polymers used to flocculate red mud particulate materials in the Bayer process can be evaluated on the basis of their efficiency to achieve adequate settling velocities and turbidity levels. In this study, three commercially available flocculants are evaluated under typical conditions found in the last washer of a Bayer plant. The different shear levels are produced by using a modified Couette flow system. Great differences are noticed in the performance of the polymers when they are compared at different dosages and at different shear rate levels. The data collected also suggests that conventional cylinder settling tests may not be adequate to measure the performance of certain types of polymers. (author)
The performance of different polymers used to flocculate red mud particulate materials in the Bayer process can be evaluated on the basis of their efficiency to achieve adequate settling velocities and turbidity levels. In this study, three commercially available flocculants are evaluated under typical conditions found in the last washer of a Bayer plant. The different shear levels are produced by using a modified Couette flow system. Great differences are noticed in the performance of the polymers when they are compared at different dosages and at different shear rate levels. The data collected also suggests that conventional cylinder settling tests may not be adequate to measure the performance of certain types of polymers. (author)
An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NOx and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.
Abstract While the techniques and technologies associated with contaminated sediment remediation are relatively mature, there are several issues associated with these practices that make them unattractive. The inability of currently used mechanical mixing implements to place amendments in aqueous environments and their intrusive behavior toward benthic communities are just two examples of a necessity for an improved delivery method. Waterjets may be a viable option for placement of particulate remediation amendments, such as activated carbon and granular iron, at depth. A custom waterjet nozzle and injection system has been fabricated by the authors to examine this delivery concept. The developed injection system's performance was tested by characterizing the waterjet-delivered amendment (...
Cholera toxin catalyzes transfer of radiolabel from ["3"2P]NAD"+ to several peptides in particulate preparations of human foreskin fibroblasts. Resolution of these peptides by two-dimensional gel electrophoresis allowed identification of two peptides of M/sub r/ = 42,000 and 52,000 as peptide subunits of a regulatory component of adenylate cyclase. The radiolabeling of another group of peptides (M/sub r/ = 50,000 to 65,000) suggested that cholera toxin could catalyze ADP-ribosylation of cytoskeletal proteins. This suggestion was confirmed by showing that incubation with cholera toxin and ["3"2P]NAD"+ caused radiolabeling of purified microtubule and intermediate filament proteins.
The project is focusing on the formation and growth mechanisms of atmospheric aerosol and cloud droplets. Both aerosol particles and cloud droplets affect strongly on the atmospheric radiation fluxes by scattering and absorption. The droplet formation results from physical and chemical processes occurring simultaneously. The studies concerning the tropospheric cloud droplet formation, laboratory experiments with a cloud chamber and stratospheric cloud formation are summarized. The recent studies summarized in this presentation indicate that both aerosol particles and cloud droplets have a significant role in climatic change and ozone depletion problems. The anthropogenic emissions of gaseous and particulate pollutants change the properties of atmospheric aerosols and cloud droplets. The research in this field will be continued and more quantitative understanding based both experimental and theoretical studies is required
Papers are presented on the modeling, dispersion, formation, transformation, monitoring and biological effects of atmospheric pollution. Specific topics include a prognostic mesoscale model for pollutant transport and diffusion, commuter exposure modeling, a Gaussian plume model for an urban area, carbon monoxide dispersion in an urbanized area, wind-tunnel modeling of flue gas dispersion, the regional-scale transport of fine aerosol components in eastern North America, and a Markov process for the generation of hourly average wind vectors. Attention is also given to photochemical aerosol formation in multicomponent systems, heterogeneous nitrogen oxide-particulate reactions, the generation and measurement of primary soot aerosols of size between 50 and 400 A, inertial particle size classification techniques, the design of air quality monitoring networks, visibilities in polluted and unpolluted areas, and monitoring air quality according to an analysis of ...
Determination of the radiocarbon (14C) content of airborne particulate matter yields insight into the proportion of the carbonaceous material derived from fossil and contemporary carbon sources. Daily samples of PM2.5 were collected by high-volume sampler at an urban background site in Birmingham, UK, and the fraction of 14C in both the total carbon, and in the organic and elemental carbon fractions, determined by two-stage combustion to CO2, graphitisation and quantification by accelerator mass spectrometry. OC and EC content was also determined by Sunset Analyzer. The mean fraction contemporary TC in the PM2.5 samples was 0.50 (range 0.27-0.66, n=26). There was no seasonality to the data, but there was a positive trend between fraction contemporary TC and magnitude of SOC/TC ratio and fo...
This report presents results of an air quality assessment program in northwestern Ontario. It includes data from communities where long term monitoring is conducted, mostly in urban areas and near industrial sources of air pollution such as mining, pulp and paper, and thermal power generation. Summaries are also presented of special studies in the Thunder Bay area. The monitoring program identifies pollution sources and assesses the results of pollution control measures. Data are included only on those contaminants routinely monitored in northwestern Ontario, including particulates, CO, NOx, ozone, SO[sub 2], total reduced sulfur, organic compunds, and heavy metals. Data from air quality and meteorological instruments are supplemented by vegetation, soil and snow sampling studies. 25 refs, 14 figs., 16 tabs.
Abstract Large areas of the southern European countries possess a Mediterranean climate, which influences soil properties, land use, fertilizer application practices and pathways of phosphorus (P) loss from agricultural soils. On average, inputs of fertilizer P exceed P exports from the agricultural areas in these countries; however, large differences in P surplus/deficit and soil P test values exist among regions. Losses of P in drainage water are modest except in some irrigated areas and in those regions where intensive animal production is concentrated. Losses of P in runoff water, whether as dissolved reactive or particulate P, can be substantial as a result of the significance of erosive processes under the land uses typical of the Mediterranean region, where extreme rainfall events c...
Abstracts are presented for about 40 papers. The Fossil Energy Advanced Research and Technology Development Materials program is an integrated materials research activity of the fossil energy coal program, whose objective is to conduct R and D for all advanced coal conversion and utilization technologies. The program is aimed at understanding materials behavior in coal system environments and the development of new materials for improving plant operations and reliability. A generic approach is used for addressing multiple coal technologies; for example, the hot-gas particulate filter development is applicable to pressurized fluidized bed combustion, integrated coal gasification combined-cycle, coal combustion, and indirectly fired combined-cycle systems.
A phenomenological model based on the multizone method is described. The model requires a relatively low amount of central processing unit (CPU) time and memory for each run and, consequently, is useful for parameter studies. The flame morphology predicted by the model is compared to that recently uncovered in experimental studies. As a demonstration of its utility, the model is used to study the effect of the oxygen content in intake air on the emission of particulate matter (PM) and NO{sub x} from a direct injection diesel engine. A parametric study reveals that while oxygen-enriched intake air is useful for reducing PM, the reduction comes with a large increase in NO{sub x} emission. The PM-NO{sub x} trade-off curve for the oxygenated intake air is worse than that for the baseline air case. (Author)
may be possible to meet those loads with renewable energy systems &mdashachieving zero-net- energy performance.Solar-thermal heating systems, ...p/p Spencer and others argue that renewable energy systems should be considered only after the building envelope ...energy loads are brought low enough, however, a renewable energy system may make sense financially. p
The experimental superconducting magnetic system of 0.5 MJ energy storage is described. The step variation of the winding inductance provides a control by the discharge current at the energy output on a high-ohmic load. The voltage on a load is 45 kV at the current 1100 A under the controllable discharge conditions. The energy transfer coefficient constitutes 0,76 under the maximum-to-minimal current ratio equal to 1.3. 7 refs., 3 figs., 2 tabs.
Wood/polymer composites (WPC) have been prepared from pinewood with different compounds using gamma irradiation: butyl acrylate, butyl methacrylate, styrene, acrylamide, acrylonitrile, and unsaturated polyester styrene resin. The polymer loading was determined with respect to the compound concentration and the irradiation dose. The polymer loading increases generally with increase in the monomer or polymer concentration. Tensile and compression strength have been improved in the four cases, but no improvement was observed using unsaturated polyester styrene resin or acrylamide.
Pile foundations are extensively used to support off-shore and on-shore structures. Under dynamic loads, the behavior of single pile is well understood. However the soil-pile-soil interaction studies are confusing, on which account the analyses do not necessarily predict response of the systems which may match satisfactorily with the performances. In this paper, the nature of dynamic loads is described, and solutions for soil-pile and pile-soil-pile interaction solutions by several authors are presented and a critical evaluation is made.
With the frequent load changes to which a hard coal power station is subjected in the middle and peak load range, great demands are linked with the transient behaviour of the steam generator. Due to the serial connection of the crusher and boiler, the strongly delaying transient behaviour of the crusher compounds entirely with the transient behaviour of the steam generator. Therefore, a suggestion is to be made here as to the improvement of the dynamics of the crusher.
These ten chapters present an overview of floating production, storage and offloading (FPSO) vessels, and examines deep water developments; hydrostatic stability; production, storage and offloading systems; the configuration and structure of flexible risers and umbilicals; the structural and global dynamic analysis of flexible riser and umbilicals; verification of FPSO structural integrity; vessel global loading and rigid body response; environmental loading and vessel response; and mooring systems. (UK)
Load-deflection characteristics of alumina and alumino-silicate fibrous blankets were experimentally determined. Load retention and springback capability of combinations of these materials were measured in a 10,000-hour test at surface temperatures of 650 to 1000"0C (1200 to 1832"0F). Experimental results are presented and future testing plans are discussed.
An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.
The Fast Flux Test Facility (FFTF) bottom-loading transfer cask (BLTC) system is designed to provide ex-vessel fuel transfers of irradiated reactor components between the reactor containment building and the LMFBR shipping cask in the reactor service building. This system is being procured from National Lead Industries, Wilmington, Delaware, under management of Aerojet Manufacturing Company.
The data center in this study had a total floor area of 8,580 square feet (ft{sup 2}) with one-foot raised-floors. It was a rack lab with 440 racks, and was located in a 208,240 ft{sup 2} multi-story office building in San Jose, California. Since the data center was used only for testing equipment, it was not configured as a critical facility in terms of electrical and cooling supply. It did not have a dedicated chiller system but served by the main building chiller plant and make-up air system. Additionally, it was served by a single electrical supply with no provision for backup power. The data center operated on a 24 hour per day, year-round cycle, and users had all hour full access to the data center facility. The study found that data center computer load accounted for 23% of the overall building electrical load, while the total power consumption attributable to the data center including allocated cooling load and ...
The applicability of conventional strength hypotheses in the long-term creep range was examined by means of multiaxial loaded small and large-scale specimens of 1% CrMoNiV-steel at 550deg C. The experimentally determined deformation behaviour in the primary and secondary creep range was simulated by means of a finite element analysis. The creep deformation capacity is influenced by the degree of multiaxiality. The validity of a strength hypothesis depends on the type of load and on deformation resp. failure criteria. (orig.).
Aluminum hydroxide coating thicknesses were measured on fuel elements stored in aluminum canisters in K West Basin using specially developed eddy current probes . The results were used to estimate coating inventories for MCO fuel,loading. Brushing tests successfully demonstrated the ability to remove the coating if deemed necessary prior to MCO loading.
A novel CFD/structural analysis was performed to predict functionality of a cross parachute under loadings near the structural limits of the parachute. The determination of parachute functionality was based on the computed structural integrity of the canopy and suspension lines. In addition to the standard aerodynamic pressure loading on the canopy, the structural analysis considered the reduction in fabric strength due to the computed aerodynamic heating. The intent was to illustrate the feasibility of such an analysis with the commercially available software PATRAN.
This paper presents actual time/motion data for an oversize truck spent-fuel shipment from its origin, Surry, Virginia to its destination, Idaho National Engineering Laboratory (INEL). These data include the receipt of the empty cask at the reactor, wet-loading the cask, over-the-road or in-transit data, and receipt and dry unloading of the shipping cask at the receiving facility. Occupational doses were recorded at the Surry Power Plant as well as at INEL, and public doses were calculated for the in-transit dose analysis. This shipment was one of a series performed in support of a demonstration and evaluation of dry storage at INEL. The oversized shipment consisted of a TN-8L shipping cask loaded with three 10-yr-old pressurized water reactor assemblies. The total distance traveled was #approx#2800 miles, requiring 62 h including stops. The time required to receive and inspect the empty shipping cask and wet-load and ...
Chitosan-filled rubber compounds were prepared using a laboratory sized two-roll mill. The effect of chitosan loading on three different types of rubber (STR 5L, ENR-25 and SBR) was investigated. The results indicate that, overall, the scorch time (t"S"2), cure time (t"9"0), tensile strength and elongation at break (Eb) decrease with chitosan loading, whereas an increment was observed in the maximum torque (MH) and the tensile modulus (M100 and M300) of all three types of rubber. At a similar chitosan loading, the cure characteristics of SBR were found to be longer (for t"S"2 and t"9"0) and higher (for MH) than those of STR 5L and ENR-25. The tensile properties of SBR were found to be the lowest of the three rubbers at a similar chitosan loading. The rubber-filler interaction for all three...
One of the most loaded parts of a steam generator of VVER 440 MW type are the bolts and thread holes of the primary collector cover sealing set. The strength calculations and tensometric measurings performed during operation proved the high degree of a load on the bolts. The conditions of the stress limitation are not met in some cases according to the pertinent standards. The untightnesses at nickel rings occurred during putting the units of Jaslovske Bohunice and Dukovany nuclear power stations into operation. With regard to improve the reliability, the producer has taken measures to improve the quality of the rings and users have introduced more strict regulations for bolts tightening. Due to these measures the high reliability of the set has been obtained from point of view of the tightness, but substantial reduction of bolts and holes threads loading have not been obtained. Several years operation experience proved ...
Five cycles of loading, elution, and regeneration were performed to remove technetium from a Hanford waste sample retrieved from Tank 241-AW-101 using SuperLig 639 resin. The waste sample was diluted to 4.95 M Na plus and then was processed to remove 137Cs through dual ion exchange columns each containing 15 mL of SuperLig 644. To remove 99Tc, the cesium decontaminated solution was processed downwards through two ion exchange columns, each containing 12 mL of SuperLig 639 resin. The columns, designated as lead and lag, each had an inside diameter of 1.45 cm and a height of 30 cm. The columns were loaded in series, but were eluted and then regenerated separately. The average technetium loading for the cycles was 250 BV at 10 percent breakthrough. There was no significant difference in the loading performances among the five cycles. The percent removal of 99Tc was greater than 99.94 percent and the ...
The Fast Flux Test Facility (FFTF) was designed to test fast-reactor fuels and other nonfuel materials. In its 37 reactor cycles of operations, the FFTF reactor has performed very well and successfully completed all the irradiation testings with an operating efficiency factor as high as 98%. Since FFTF is an experimental reactor, its core loading changed from cycle to cycle. Depending on the number of test assemblies in the core and their location, the core loading can change significantly from an essentially homogeneous core loading to a relatively nonhomogeneous or even highly localized heterogeneous loading. Consequently, the core reload design and initial criticality analyses were required for each operating cycle. The zero power initial critical control rod bank height was predicted before each reactor startup. The initial critical prediction depends on the reactivity conditions at the end of the ...
Vegetation is a key compartment of ecosystems. It contains a large part of the biodiversity at the species level. For the evaluation of critical loads, we have to separate different receptors: lower plants (algae, fungi, lichens and mosses) and vascular plants. Trees must be distinguished due to their economic value. We analyze the different changes that pollution produces on vegetation: the state of health of individuals, changes in the biology and genetics at the population level, changes in the biodiversity or the specific composition at the community level. Calculation of critical loads is based on observational or experimental studies, in more or less controlled environments. However, they cannot yet be obtained through models of vegetation changes. Some results have been acquired at the European level, mainly for critical loads for nitrogen, but these results have come mostly from Northern Europe. Moreover, only ...
Zone modeling permits taking account of the effect of load-relieving air conduction systems in the planning of HVAC plants. Although this only supplies average values for the degree of load and height of the fresh air layer rather than a detailed description of concentration and temperature distributions in the room, it is quite sufficient for the planning of load-relieving air conduction systems. Moreover, the cost of zone modeling in the planning of HVAC plants remains within reasonable limits. Upscale planning, instruments can thus be reserved for more exacting problems. (orig.) [Deutsch] Zonenmodelle erlauben die Wirkung lastmindernder Luftfuehrungen bei der Planung von RLT-Anlagen zu beruecksichtigen. Sie liefern zwar nur Mittelwerte fuer den Belastungsgrad und die Hoehe der Zuluftschicht und keine detaillierte Konzentrations- und Temperaturverteilungen im Raum. Diese Werte reichen jedoch fuer die Planung ...
Reinforcement of the legislation concerning the emission of atmospheric pollutants, aerosols, refrigerants, solvents etc and the reduction of the greenhouse effect, has led to the development of performing instruments for the survey and control of ambient air quality and for the limitation of exhaust gases, combustion products, volatile organic compounds (VOC), particulates and noxious compounds in the atmosphere. This study is divided in 4 main parts. The first part describes the context of the air quality control: the problems linked with the environment and health, the pollutants characteristics, the pollution levels and the detection sensitivity of instruments according to the different type of pollutants (petroleum products, VOCs, ozone compounds, particulates, smells..), the protocols of air pollution measurements and their application (chimney smokes, industrial volatile compounds, indoor and ambient air quality, exhaust gases from ...
Airborne fine particle sulfur data from the summer intensive of Project MOHAVE (Measurement of Haze and Visual Effects) was analyzed by the Receptor Model Applied to Patterns in Space (RMAPS) model, a novel multivariate receptor-oriented model that applies to secondary and primary species. The sulfur data from 17 sites were found to be well predicted by three spatial patterns interpreted as sources along the valley of the Colorado River (including the large Mohave coal-fired power plant, a smaller power plant and the city of Las Vegas); transport from sources located to the southwest; and transport from sources located to the southeast. The model was tested by using parameters derived from the 17-site data set to apportion sulfur for six sites that were not part of the original data set. The sulfur apportionment for these site sites was in agreement with the original apportionment and the physical interpretation of the spatial patterns given above. The effects of systematic and random ...
Particulate ceramic composites that were composed of a combustion-synthesized #beta#'-SiAlON matrix and dispersed MoSi_2 particles were hot pressed at 1,600 C in a nitrogen atmosphere. The physical and mechanical properties of the composites that contained 15, 30, and 45 vol% MoSi_2 were evaluated. The average four-point bend strength, fracture toughness, and Vickers hardness of the composites were in the ranges of 500--600 MPa, 3--4 MPa#centre dot#m"1"/"2, and 11--13 GPa, respectively. The measured mechanical strength and hardness were very similar to the values that were predicted from the rule of mixtures. The fracture toughness of the combustion-synthesized #beta#'-SiAlON (2.5 MPa#centre dot#m"1"/"2) was apparently enhanced by the MoSi_2 particles that were added. The increase in the fracture toughness was predominantly attributed to the residual thermal stress that was induced by the thermal expansion mismatch between the MoSi_2 particles and the ...
There is a need to reduce air pollutant emissions in some U.S. urban regions to meet federal and state air quality guidelines. Opportunities exist for reducing pollutant emissions from natural gas appliances in the residential sector. A cost-benefit analysis on various pollutant-reducing strategies is needed to evaluate these opportunities. The effectiveness of these pollutant-reducing strategies (e.g., low-emission burners, energy conservation) can then be ranked among themselves and compared with other pollutant-reducing strategies available for the region. A key step towards conducting a cost-benefit analysis is to collect information on pollutant emissions from existing residential natural gas appliances. An extensive literature search was conducted to collect data on residential natural-gas-appliance pollutant emission factors. The literature primarily describes laboratory tests and may not reflect actual emission factor distributions in the field. Pollutant emission factors for ...
The Coal Fired Combined Cycle (CFCC) is the unique powerplant concept developed under the leadership of the General Electric Company to provide a direct coal-burning gas turbine and steam turbine combined cycle powerplant. On the basis of previous studies and confirming work under this contract, General Electric continues to believe that the CFCC approach offers important advantages over alternate approaches: higher powerplant efficiency in the combustor temperature range of interest; reduced combustor/steam generator corrosion potential, due to low fluid-bed tube temperature (as contrasted to the air in tube cycle); and increased gas turbine bucket life from improved material protection systems. The objective of this program is to evaluate the coal fired combined cycle powerplant conceptual design, and to conduct a supporting development program. The supporting development is required for evaluating the pressurized fluidized bed combustion concept, for developing engineering ...
The conversion of highly radioactive waste liquor into glass by the pot vitrification process has been studied at Harwell using a full-scale inactive pilot plant. A summary of the off-gas behavior and its interpretation is presented. Experimental runs were carried out on 3 representative wastes (MAGNOX - thermal reactor, metal fuel, THORP - thermal oxide fuel and PFR - fast reactor oxide fuel) using 2 methods of feeding the glass-formers (slurry and crizzle). Materials were carried over from the vitrification vessel into the off-gas system by entrainment supplemented by volatilization. The overall behavior of the off-gas was consistent with the presence in it of 5 separate aerosols of particulate matter. Sources of entrainment gave rise to 3 aerosols, and a further 2 aerosols were formed as a result of chemical reaction (Ru) and condensation (Cs) processes involving the volatile species. Entrainment was enhanced when the feed contained free alkali nitrate. The Ru ...
A summary of the off-gas behavior in the HARVEST pot vitrification process is presented. Experimental runs were carried out on 3 representative wastes (MAGNOX - thermal reactor, metal fuel, THORP - thermal oxide fuel and PFR - fast reactor oxide fuel) using 2 methods of feeding the glass-formers (slurry and crizzle). Materials were carried over from the vitrification vessel into the off-gas system by entrainment supplemented by volatilization. The main volatile elements were Ru, B, Cs. Some volatility was also shown by Na and Li. The overall behavior of the off-gas was consistent with the presence in it of 5 separate aerosols of particulate matter. Sources of entrainment gave rise to 3 aerosols, and a further 2 aerosols were formed as a result of chemical reaction (Ru) and condensation (Cs) proceses involving the volatile species. Entrainment was enhanced when the feed contained free alkali nitrate. The Ru volatility correlated directly with the amount of salt ...
Objectives: We have previously shown that chronic exposure to ambient fine particulate matter (less than 2.5 ?m in aerodynamic diameter, PM(2.5)) pollution in conjunction with high-fat diet induces insulin resistance through alterations in inflammatory pathways. In this study we evaluated the effects of PM(2.5) exposure over a substantive duration of a rodent's lifespan and focused on the impact of long-term exposure on adipose structure and function.Methods and Results: C57BL/6 mice were exposed to PM(2.5) or filtered air (FA) (6 hours/day, 5 days/week) for duration of 10 months in Columbus, OH. At the end of the exposure, PM(2.5)-exposed mice demonstrated insulin resistance (IR) and a decrease in glucose tolerance compared with the FA-exposed group. Although there were no significant differences in circulating cytokines between PM(2.5)- and FA-exposed groups, circulating adiponectin and leptin were significantly decreased in PM(2.5)-exposed group. PM(2.5) ...
Dissolved humic substances (humic and fulvic acids) occur in surface waters and groundwaters in concentrations ranging from less than 1 mg(C)/L to more than 100 mg(C)/L. Humic substances are strong complexing agents for many trace metals in the environment and are also capable of forming stable soluble complexes or chelates with radionuclides. Concentrations of humic materials as low as 1 mg(C)/L can produce a detectable increase in the mobility of some actinide elements by forming soluble complexes that inhibit sorption of the radionuclides onto rock materials. The stability of trace metal- or radionuclide-organic complexes is commonly measured by an empirically determined conditional stability constant (K'), which is based on the ratio of complexed metal (radionuclide) in solution to the product concentration of uncomplexed metal and humic complexant. Larger values of stability constants indicate greater complex stability. The stability of radionuclide-organic complexes is ...
The PPCC technology, a combined cycle, requires comprehensive cleaning of the flue gases because coal contains a large variety of minerals and other substances. This would lead to fast destruction of the gas turbine blades due to erosion and corrosion. The present specifications of the turbine manufacturers for the required flue gas quality are at a maximum particulate content of 5 mg/m3 s.t.p., diameter of < 5 {micro}m, and a maximum alkali content < 0.01 mg/m3 s.t.p. The PPCC project is aimed at cleaning the flue gases of pressurized coal combustion. This method will be applied at temperature ranges where the ash is in a liquid state and which will be thus cleaned from coarse particulate material by agglomeration and inertial force separators. Appropriate separating methods are also being investigated and developed for the hazardous gaseous contents, e.g. alkali compounds, which are released during the coal combustion process. ...
Feline heartworm disease is a very different clinical entity from canine heartworm disease. In cats, the arrival and death of immature heartworms in the pulmonary arteries can cause coughing and dyspnea as early as 3 months postinfection. Adult heartworms suppress the function of pulmonary intravascular macrophages and thus reduce clinical disease in chronic feline heartworm infection. Approximately 80% of asymptomatic cats self-cure. Median survival time for symptomatic cats is 1.5 years, or 4 years if only cats living beyond the day of presentation are considered. Aberrant worm migration is more frequent than it is in dogs, and sudden death can occur with no prior clinical signs. The bacterial endosymbiont Wolbachia likely contributes to the inflammatory pathology of heartworm disease, but its role is not yet fully clear. Unfortunately, the diagnosis, treatment, and management of feline heartworm disease are far from simple. Antemortem diagnosis is hampered by ...
Scrotal skin of black Long-Evans rats and human thigh skin were maintained in vitro as organ cultures for as long as 14 days, and examined histologically using the combined skin splitting and Dopa techniques. Selected rat skin cultures received testosterone in the culture medium and/or were irradiated with ultraviolet light (290 to 320 nm uvl). With increased time in culture, scrotal melanocytes round up and there is an increase in epidermal pigmentation. Human skin behaves similarly; after eight days in vitro human melanocytes also become rounded, but remain strongly Dopa-positive. Addition of exogenous testosterone to cultured rat skin maintains dendritic morphology of melanocytes, but cell body size is still reduced. uvl irradiation stimulates melanocytes in rat skin cultures, maintaining their dendritic morphology and increasing epidermal and dermal pigmentation. Cultured skin receiving both uvl and testosterone illustrates a synergistic effect. Electron microscopic examination of ...
BackgroundIn recent years, near-infrared fluorescence (NIRF)-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area.ResultsThis study manufactured 12-nm DMSA-coated Fe3O4 nanoparticles labeled with a near-infrared fluorophore, IRDye800CW (excitation/emission, ...
This paper summarizes results of preliminary experiments to develop cytological and biochemical indicators for estimating damage to respiratory cells in test animals exposed by inhalation to toxic agents associated with nonnuclear energy production, the specific goal being the application of advanced multiparameter flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. Normal Syrian hamster lung cell samples composed of histiocytes, leukocytes, macrophages, ciliated columnar cells, and epithelial cells were stained with fluorescent dyes specific for different biochemical parameters and were analyzed in liquid suspension as they flowed through a chamber intersecting a laser beam of exciting light. Multiple sensors measured the total or two-color fluorescence and light scatter on a cell-by-cell basis. Cellular parameters proportional to optical measurements (i.e., cell size, DNA content, total protein, nonspecific esterase ...
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Some fractions of Him-I and Him-II increased the proliferation of bone marrow cells irradiated {gamma}-ray(4Gray). Stimulation of macrophage cell line with herval extracts with the ...
Influenza virus infection during pregnancy has been implicated as one of cause of premature delivery, abortion and stillbirth. We have reported that cultured human fetal membrane chorion cells undergoing apoptosis by influenza virus infection secrete unidentified heat-stable monocyte differentiation-inducing (MDI) factors. In this study, cellular, biological and immunochemical characteristics of MDI factors were investigated using human monocytic leukemia THP-1 cells by nitroblue tetrazolium reduction and cell adhesion assays. The treatment of THP-1 cells with culture supernatants from the influenza virus-infected chorion cells induced the nitroblue tetrazolium reduction ability, which was inhibited by the addition of superoxide dismutase and diphenyleneiodonium chloride, an inhibitor for reduced nicotinamide adenine dinucleotide phosphate oxidase. The phenomenon was also observed in human peripheral blood monocytes and histiocytic leukemia U937 cells, but not in promyelocytic leukemia ...
One of the limiting contributors to the heat load constraint for a long term spent fuel repository is the decay of americium-241. A possible option to reduce the heat load produced by Am-241 is to eliminate it via transmutation in a light water reactor thermal neutron environment, in particular, by taking advantage of the large thermal fission cross section of Am-242 and Am-242m. In this study we employ lattice loading optimization techniques to define the loadings and arrangements of fuel pins with blended americium and uranium oxide in boiling water reactor bundles, specifically, by defining the incineration of pre-loaded americium as an objective function to maximize americium transmutation. Subsequently, the viability of these optimized lattices is tested by assembling them into bundles with Am-spiked fuel pins and by loading these bundles into realistic ...
Due to the cyclical human life, utility loads appear to be cyclical too. During daytime when most factories are in operation, the electricity demand is very high. On the contrary, when most people are sleeping from midnight to daybreak, the electric load is very low, usually only half of the peak load amount. To meet this large gap between peak load and light load, utilities must idle many generation plants during light load period while operating all generation plants during peak load period no matter how expensive they are. This low utilization factor of generation plants and uneconomical operation have sparked utilities to invest in energy storage devices such as pumped storage plants, compressed air energy storage plants, battery energy storage systems (BES) and superconducting magnetic energy storage systems (SMES) etc. Among these, ...
A simple approach to controlling the loading percentage and size of zero-valent iron nanoparticles (ZVI NPs) immobilized within polyacrylic acid (PAA)/polyvinyl alcohol (PVA) nanofibrous mats for dye remediation applications is described. A functional "nanoreactor" comprised by electrospun PAA/PVA nanofibers served to bind ferric ions with the carboxyl groups of PAA, prior to their reduction to ZVI NPs. The resulting ZVI NP-immobilized hybrid polymer nanofibers were characterized using scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis. The morphology of the polymer nanofibers exhibited no appreciable change even after eight cycles of ferric ion binding/reduction, and the loading percentage and size of the ZVI NPs were controlled simply by varying the number of ferric ion binding/reduction cycles. Dye remediation experiments revealed that the decoloration effect of ZVI NPs immobilized within the ...
Nitrate microelectrodes and ORP microelectrodes were fabricated to study the denitrification characteristics of dynamic membrane at different COD loadings. The denitrification process was found at 0.6-1 mm depth beneath the interface of biofilm/bulk. The results of ORP microelectrode also demonstrated that the ORP value in the range of denitrification area was between 88.6 approximately -128.4 mV which was appropriate to denitrification. When the COD loading was 0.45 kg/(m3 x d), the denitrification rate (NO3- -N) was the maximum of 0.6347 x 10(-6 mol/(L x s). With the increase of COD loading, the denitrification area was increasing and two layers with different denitrification rates emerged in the dynamic membrane. The phenomenon implied the effect of organic concentration, oxygen concentration and bacterial competition on the denitrification rate. PMID:17117632
In general, the tickover speed of a car engine is made sufficiently high, in order to permit an assumed maximum load to be taken from the engine at tickover. This setting of the tickover speed is usually done by stops in the fuel supply. Matching the actual load would lead to lower fuel consumption, without any danger of the engine stalling. The purpose of the invention is to provide a tickover speed controller, so that the tickover speed is adjusted by electronic control equipment, independently of the machine load. The fuel consumption on tickover is reduced and the emission of noxious substances is decreased. The electro-magnetic control of the throttle valve tickover setting is explained by extensive section drawings of the system. This process dispenses with the special tickover cams for a cold start.
Power loadings experienced by tokamak plasma-facing components during normal operation and during off-normal events are discussed. A model for power and particle flow in the tokamak boundary layer is presented and model predictions are compared to infrared measurements of component heating. The inclusion of the full three-dimensional geometry of the components and of the magnetic flux surface is very important in the modeling. Experimental measurements show that misalignment of component armour tile surfaces by only a millimeter can lead to significant localized heating. An application to the design of plasma-facing components for future machines is presented. Finally, thermal loads expected during tokamak disruptions are discussed. The primary problems are surface melting and vaporization due to localized intense heating during the disruption thermal quench and volumetric heating of the component armour and structure due to localised impact of ...
In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been conducted in searching for suitable adjusting methods for the GHPS and on the subsequent effects on the working parameters of the GHPS. Firstly, several methods are compared, and it is found that the method of adjusting the compressor's rotation speed using a transducer is better than the others. Secondly, this method is experimented on a small scale GHPS at frequencies ranging from 30 to 55 Hz. The analysis of the experimental data reveals the relationships between the compressor frequency and other important parameters, such as coefficient of performance, heat capacity, cool capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS. (Author)
This paper is concerned with the fracture analysis of thin cylindrical shells subject to secondary bending stresses with some degree of elastic follow-up. A P.Y.F.M. failure assessment route is utilised for an initial investigation. Results are presented graphically and indicate the differences obtained by considering the stresses as primary or secondary in nature. The Jsup(*) contour integral is computed from the results of a non-linear finite element analysis of a thermally loaded cracked cylinder. Comparison is made between Jsup(*) and the P.Y.F.M. failure criteria demonstrating the degree of conservatism in the latter. It is observed that LEFM may be appropriate for moderate load levels but that the elastic follow-up of the structure causes enhancement of Jsup(*) for higher loads, at which stage LEFM becomes non-conservative. (orig.).
In order to perform the structural analysis and stress evaluation for frame structures in the nuclear power plants, ADAMS (AIJ Design Analysis and Modules System) has been developed by the addition of the following functions to the ICES-STRUDL system. 1. Load combination and stress evaluation on the basis of specifications for designing steel structure (issued by the Architecture Institute of Japan). 2. Combination of load and stress evaluation of piping support on the basis of the regulations of Ministry of International Trade and Industry. 3. Addition of other functions than that described above. ADAMS enables structural analysis and stress evaluation exactly and efficiently not only for a large scale structure such as the pipe whip protection structure installed inside of the primary containment vessel for many loading cases but also for a large number of structures such as piping support. This system can be applied not ...
A distributed watershed hydrologic model soil and water assessment tool (SWAT, 2000 Version) was applied to simulate stream flow and nutrient loadings (including total nitrogen (TN) and total phosphorus (TP)) in Gucheng Lake Basin, which is located in the lower reach of Yangtze River Basin. Model parameters related to stream flow and nutrient loadings were calibrated and validated by the observed value, and the simulation showed that the simulated values were reasonably comparable to the observed data, suggesting the validity of SWAT model. The simulated surface runoff and nutrient yield between two stages, viz. 1981-2000 and 1951-1960, were compared, basically considering land reclamation in the mid-1970s. The result indicated that, the average annual runoff and output of TN and TP in 198...
The paper discusses the aspects of repair and retrofitting technique adopted for a damaged reinforced concrete beam-column joint specimen under cyclic loading. A specimen designed based on Indian Standard specifications with consideration of seismic load but without adopting ductile detailing (NonDuctile) was investigated under reverse cyclic loading. Then, the damaged nonductile specimen was repaired with epoxy mortar and grouted using low viscous polymer, and retrofitted using fiber reinforced plastic (FRP) wrapping in beam and column components and steel plate jacketing in joint region. The experimental results showed that the retrofitted specimen not only regained its original strength and stiffness but also has overcome the deficiencies of nonductile detailing. The present study shows...
A new controlled-clearance pressure balance is under development with the aim of improving the hydraulic high-pressure standard up to 1 GPa. This pressure balance consists of three parts: (i) a pressure generation device up to 1 GPa, (ii) a weight-loading unit which can load/unload weights automatically and independently, (iii) a controlled-clearance piston-cylinder which is designed to allow the jacket pressure to be applied independently. Some adjustments were made for loading heavy weights on/off the piston safely, keeping them in balance, then generating the pressure stably. Stability of the generated pressure was checked for several piston-cylinders, and it was found that pressure fluctuation was less than a few parts per million. The jacket pressure coefficient of a 500 MPa controlled-clearance piston-cylinder was precisely evaluated as a function of both the system pressure and the jacket pressure.
The ability of the /sup 252/Cf-source-driven neutron noise analysis method to measure subcriticality has been demonstrated in a variety of experimental configurations of fissile materials. Calculations for an approximately 4-m-dia configuration of light water reactor (LWR) fuel elements indicated the feasibility of measuring the subcriticality of large, loosely coupled arrays of LWR fuel elements by this same method. These analysis suggested application to the initial loading of both pressurized and boiling water reactors, zero-power testing of reactors (such as shutdown margin measurements after initial loading), light water reactor refueling, and safe storage of LWR spent fuel. In the fuel storage application, direct measurement of subcriticality in the actual fuel storage facilities provides the parameter which is directly related to criticality safety.
The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)
A compression ignition engine was operated on dual fuel principle inducting two commercial fuels and four pure hydrocarbon fuels in turn through intake manifold along with air and injecting diesel fuel to initiate the combustion in the conventional manner. The engine was operated at different loads and at each load the quantity of inducted fuel was increased gradually till knocking set in. The engine performance and exhaust pollutant emissions were recorded at different operating conditions. It was observed that the extent of induction and the effect on the performance depend on the properties of the inducted fuel such as volatility, self ignition temperature and oxidation characteristics. The energy release during the cycle was also observed to shift depending on the properties of inducted fuel. With the dual fuel operation, the thermal efficiency at part loads was observed to be less compared to neat diesel operation. The ...
Summary. Ratiometric fluorescent dyes are often used to monitor free ion concentrations in vivo, especially in cells that are recalcitrant to transformation with genetically encoded fluorescent markers. Although intracellular dye distributions are often found to be cytosolic, dye localisation has often not been examined in detail. We began exploring the use of BCECF (2?,7?-bis(2-carboxyethyl)-5(6)-carboxyfluorescein) to monitor pH in the giant alga Chara australis and discovered that younger leaf cells could be loaded using the acetoxymethyl ester of BCECF. However, we were puzzled to find in microphotometric measurements that the fluorescence ratio appeared insensitive to manipulations affecting cytosolic pH. Confocal imaging of C. australis cells loaded with BCECF showed an accumulation ...
The Department of Energy has proposed a rulemaking process to set minimum standards for the efficiency of gas ranges under the National Appliance Energy Conservation Act (NAECA). The Gas Research Institute is compiling information on annual household range gas usage in order to prepare a response to the proposed rulemaking. The data base from the Northern Illinois Gas residential load study provides recent information (data taken from 1990 through 1992) over a comprehensive study of household types and appliance and user characteristics (150 variables noted for each household). The stated Objective is to study the Northern Illinois Gas residential load study data base and to evaluate its effectiveness in predicting annual household gas usage.
The mechanical stability of diamond-like carbon (DLC) films coated on nitinol vascular stents was investigated under cyclic loading condition by employing a stent crimping system. DLC films were coated on the vascular stent of a three dimensional structure by using a hybrid ion beam system with rotating jig. The cracking or delamination of the DLC coating occurred dominantly near the hinge connecting the V-shaped segments of the stent where the maximum strain was induced by a cyclic loading of contraction and extension. However the failures were significantly suppressed as the amorphous Si (a-Si) buffer layer thickness increased. Interfacial adhesion strength was estimated from the spalled crack size in the DLC coating for various values of the a-Si buffer layer thickness.
Bags of explosive are loaded rapidly into deep wellbores by suspending a rigid positioning tube partway into the wellbore, and loading the bags into the tube, the bags being prevented from dropping through the open bottom end of the tube by a cord attached to the lowermost bag and secured at the upper end of the tube when the tube-suspending cable is in tension by a cordsecuring/releasing means, E.G., a pivotable bar having a hook on one end. When the bag-laden tube is lowered to the bottom of the wellbore, or to a column of bags previously placed therein, the tension on the cable is relaxed and the cord is released, allowing the positioning tube thereafter to be raised to the surface for re-use, leaving the cord and bags in the wellbore. Freedom of the bag-supporting cord to move with respect to the positioning tube when the latter is raised to the surface is assured by threading the cord through plastic tubing mounted to the wall of the ...
In the WWER-440 reactor the primary piping consists of six horizontal loops going radially from the pressure vessel, each loop having a horizontal steam generator. In this reactor type the relatively long primary piping with many curved sections requires special attention in order to successfully eliminate the consequences of the design basis accident. Emergency supports are located in appropriate places to restrict the movements of the pipe. Under normal conditions there is a gap of some centimeters between the pipe and a support so that in the pipe can be deformed freely under changing loads. This paper deals with those energy-absorbing structures used at the Loviisa Nuclear Power Plant for protection against impact loading. Places and circumstances where energy-absorbing structures are employed are specified. Development and design of impact absorber elements are discussed and impact tests are described. (Auth.).
Investigations were conducted on the range of emission rates of NO, NO[sub 2], CO and hydrocarbons, and the thermal efficiencies produced by each burner on three production cookers, supplied by different Australian manufacturers. It was found that the emissions and efficiencies were markedly affected by (1) the thermal input, both with and without a load on the burner, and (2) the load-height to flame-length ratio, with a load on the burner. The effect of hydrocarbon leakage into the secondary/dilution air was investigated, to explain the observed correlation of hydrocarbon emission rate with dilution air flow. The hydrocarbons were found to arise from two sources: -leakage from the stabilisation ports at the base of the burner, which was found to be significant at the higher thermal input; -incomplete combustion of the fuel in the premix, which was the dominant source of hydrocarbons emissions at the lower thermal input. ...
The authors obtain the critical load levels corresponding to the onset of spalling microdamage for Armco iron and steels St.3 and 12Kh18N10T in a broad temperature range (-196-800 degrees C. The results of the investigation of the effect of the temperature on spalling fracture are presented. The effect of the loading time on the strength of the investigated materials is also given. The authors assume that at -196 degrees C impact-wave strain-hardening may also be characterized by the value of H obtained for the center of the specimen since measurements on great thicknesses, including those reaching as far as the opposite surface, did not reveal any substantial change of microhardness.
ABSTRACT Purpose: The aim of this two-center study was to evaluate screw-type titanium implants with a chemically modified, sandblasted and acid-etched surface when placed in the posterior maxilla or mandible, and loaded 21 days after placement. Material and Methods: All 56 patients met strict inclusion criteria and provided informed consent. Each patient displayed either a single-tooth gap, an extended edentulous space, or a distal extension situation in the posterior mandible or maxilla. Eighty-nine dental implants (SLActive, Institut Straumann AG, Basel, Switzerland) were inserted according to an established nonsubmerged protocol and underwent undisturbed healing for a period of 21 days. Where appropriate, the implants were loaded after 21 days of healing with provisional restorations i...
Process engineers can predict quickly and accurately the equilibrium behavior of simultaneous H/sub 2/S and CO/sub 2/ absorptions in monoethanolamine and diethanolamine systems by using the nomographs developed by H.K. Ferguson Co. Correlation lines for temperature and amine concentration provided with the loading curves make the nomographs useful for any combination of temperature, concentration, and liquid loadings. The accuracy of the nomographs is within the acceptable range for normal engineering applications when the operating parameters lie in the region of practical gas-treating conditions. Correction curves given for each nomograph to improve the accuracy are generally not needed except for cases where the gas loadings are higher than 0.5 mole/mole of amine.
Microstructural observations of damage around indentations in Ti{sub 3}SiC{sub 2} are presented. The Vickers hardness decreased with increasing load and asymptotically approached 4 GPa at the highest loads. No indentation cracks were observed even at loads as high as 300 N. Preliminary strength versus indentation plots indicate that, at least for the large-grained material ({approx}100 {micro}m) studied here, Ti{sub 3}SiC{sub 2} is a damage-tolerant material able to contain the extent of microdamage to a small area around the indent. The following multiple energy-absorbing mechanisms have been identified from scanning electron micrographs of areas in the vicinity of the indentation: diffuse microcracking, delamination, crack deflection, grain push-out, grain pull-out, and the buckling of individual grains.
The operation of pumped-storage plants (PSP) is based on the daily load variations of power demand. It performs power generation at peak load times during the day, and pumps water up into the reservoir during the off-peak times at night. In the Taipower system in Taiwan, there are two pumped storage plants with ten units. These had a total installed capacity of 2,602 MW or a 12 percent capacity at the end of 1995. The plants were able to reduce system generation costs and improve reliability. A Pumped-Storage Plant Benefit Analysis (PSPBA) program was established using the principle of economic dispatch in 1985. This paper explains the rules of the program, the analysis results of the past 10 years, and a a cost benefit evaluation. It was found that the advantages of PSP are not only in supplying the power for peak load, but also in decreasing the total fuel cost. 5 figs., 4 refs.
A non-resonant RF cavity loaded with amorphous alloy cores has been designed and tested. The cavity has a re-entrant structure loaded with 8 amorphous alloy toroidal core and its characteristic impedance is designed as 450 Omega . The RF power is fed by 1 kW solid state amplifier using a step-up transformer with 1:9 impedance ratio. In the high power test, an accelerating gap voltage of more than 900 V was measured with input power of 1 kW in the frequency range of 1 to 10 MHz. The voltage standing wave ratio (VSWR) was less than 2.0. The results prove that the cavity may be used successfully within a compact proton synchrotron for a cancer therapy facility. (3 refs).
In recent years, interest in the development of a polymer electrolyte fuel cell (PEFC) has considerably increased due to its advantages (e.g., high power density) compared with other fuel cell systems, and its potentials to become the power plant for the next generation, nonpolluting automobile engine. For large scale application of fuel cells, low platinum loading electrode structures are necessary. An electrode based on a highly porous carbonized polyacrylonitrile foam material with very low platinum loading ({approximately} 13 {micro}g/cm{sup 2}) was prepared. The performance of this electrode for oxygen reduction was evaluated and compared with bulk platinum and glassy carbon electrodes.
This is the quarterly progress review report for Wolsung NPP 2, 3, 4 NSSS design and engineering which evaluates the performance of project and describes the project highlight, manpower loading status, design and engineering and project related meeting by...
Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This paper discusses the development of a model for the simulation of these stochastic loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Streamtube analysis is employed, which includes the effects of wind shear. Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. Calculations are presented for the VAWT 34-m Test Bed currently being assembled at Bushland, Texas. Time histories of the loads, as well as their Fourier spectra, are presented and discussed. An unexpected finding is that the average output power is predicted to ...
In General Electric's design of the Simplified Boiling Water Reactor (SBWR), The depressurization valves (DPV) are installed in the reactor pressure boundary: four are connected to the reactor vessel by means of nozzles, and two more are located on the main steam pipes (one DPV for each line), which act during particular transients and/or loss of coolant accidents (LOCA), consequently providing the reactor vessel with a safe quick depressurization system. Once the vessel is de pressurised, the passive gravity-driven cooling system (GDCS) starts to operate, permitting the injection of water required for continuous core cooling. DPVs are leak tight, with welded flaps, actuated by a [striker[hammer***] which is activated by an explosive mixture. The dynamic loads that open these valves include, in addition to those produced by steam (typical in any thermodynamic transient with open/close valves), other important loads that are characteristic of ...
Most pumped-storage plants have the capability to operate as synchronous condensers. As such, they can be brought on line very quickly to support system load requirements. However, one of the effects of making a rapid transition from synchronous condenser operation to turbine/governor operation is an initial reverse power flow into the machine. This reverse power flow can be very undesirable at a time when the system is calling for load support. On weak or isolated systems, this reverse power flow can lead to objectionable voltage and frequency dips in the system. With the proper utilization of a static frequency converter (SFC) and its associated controls and auxiliary switchgear systems, the reverse power flow resulting from a transition from synchronous condenser operation can be eliminated. This paper will describe the method by which an SFC system can be used to make this rapid load response in pumped-storage plants ...
The mini-chromosome maintenance proteins Mcm2–7 are essential for DNA replication. They are loaded onto replication origins during G1 phase of the cell cycle to form a pre-replication complex...Full Text Available
By placing a discharge or 'dump' tube across an exploding bridgewire load, it is possible to by-pass the electrical energy and terminate the explosion of the wire. The dump tube is triggered by a signal derived from the energy removed from the storage cap...
Wood Plastic Composite (WPC) was prepared with simul (soft wood, density = 0.4g/cc) and butylmethacrylate (BMA) monomer using 10% methanol as the swelling agent. Effect of additives including (i) multifunctional acrylates such as tripropylene glycol diacrylate (TPGDA), trimethylol propane triacrylate (TMPTA) (ii) oligomer acrylates like the urethane (UA), epoxy (EA) and polyester (PEA) acrylates and (iii) N-vinyl pyrrolidone (NVP) was investigated using 1 to 3 Mrad dose at 0.8 Mrad/h. Synergistic increases in polymer loading yields was achieved in presence of the additives, particularly with the trifunctional acrylate (TMPTA). In addition, acid as well as urea were also used as co-additives and synergistic enhancement in yields of polymer loading were obtained. The synergistic polymer loading by acid addition causes substantial decrease in tensile strength of the composite; but other additives and co-additives increase both ...
This work presents an analysis of the operation of a multi-cylinder, tubro charged, indirect injection diesel engine from a second-law analysis point of view. For this purpose, a single-zone thermodynamic model following the filling and emptying modelling technique is developed. A second-law analysis is performed in all parts of the diesel engine plant, which provides all the existing availability terms and accounts for the evaluation of every component`s irreversibilities. A complete second-law terms tabulation is given for the maximum speed-full load operation case, which is compared with its first-law counterpart. A detailed parametric study is performed in all parts of the diesel engine plant comprising the effects of speed and load on the availability terms in a range that covers the whole operation of the engine under turbocharged action. Various second-law (availability) terms such as indicated and brake work, heat transfer, inlet air, ...
In order to study the boundary conditions for the occurrence of ratcheting, a testing rig was erected. In this rig, small-scale mock-ups of the first wall were tested under mechanical conditions similar to those expected during disruptions. These mock-ups were made of stainless steel AISI 316. They were heated on the surface and water cooled from inside. Disruption forces were simulated by a high-speed hydraulic bending system by impact loads. The mock-ups were heated by a high-frequency generator and cooled by water through two cooling channels.In addition to the experimental work, simplified analytical analysis and numerical calculations were carried out using the finite element program ABAQUS. In these calculations, the temperature and stress fields in the mock-ups were investigated and the influence of the different constitutive equations was studied.The experimental results confirm the ratcheting behaviour predicted by the calculations. It has been ...
The article presents measures for the solution of construction-biological problems and for reducing the pollutant load of buildings. (HW) [Deutsch] Der Artikel berichtet ueber Massnahmen ueber Sanierung von baubiologischen Schwachstellen und Schadstoffbelastungen in Gebaeuden. (HW)
BackgroundCalcitonin gene related peptide (CGRP) is a neuropeptide that is abundant in the sensory neurons which innervate bone. The effects of CGRP on isolated bone cells have been...Full Text Available
Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm"3 volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone density and the fracture load ...
Probabilistic sensitivities using the score function method are developed for a lifing analysis of an alpha + beta titanium alloy in a round bar under axial fatigue load. Sensitivities with respect to the statistical inputs of the crack initiation size (a...
Indomethacin, a potent nonsteroidal anti-inflammatory drug, has been used in the treatment of various kinds of pains, inflammation and arthritis. However, oral administration of indomethacin produces...Full Text Available
Excised sheets of canine myocardium were subjected to cyclic loading and unloading in the predominant fibre and cross-fibre directions to determine passive mechanical properties. Myocardium under biaxial...Full Text Available
The Heliophysics roadmap: "The Solar and Space Physics of a New Era: ..... Improved materials and manufacturing processes to produce Iridium/Rhenium apogee class ... In addition to batteries, other advanced energy storage/load leveling ...
loading,W/S = k. 390 og~uda per squsre foot. Total rudder movement,. Total pedal movement, 30.64?. Radius of pedel about center of rotation,. 12 inches ...
This study deals with the torsional response of Ti-8823 and 18Ni (200) maraging steel. The effect of different heat treatments and the subsequent change in microstructure are investigated. In the case of the Ti-8823, a comparison was made between the solu...
Bone remodeling is necessary to avoid microdamage accumulation, which could lead to whole-bone failure. Previous studies have shown that this bone-repair mechanism is triggered by osteocyte apoptosis....Full Text Available
The first offshore wind farm in Sweden; Bockstigen, consists of five 500 kW stall controlled wind turbines on mono pile foundations. The main objectives of the technical evaluation are to verify the original design assumptions made for a load carrying mono pile and bedrock, investigate offshore power production versus onshore ditto as well as to determine park effects and analyse meteorological multi-mast statistics which serve as reference data to a newly developed computer code for offshore wind energy potential mapping. The 'main' measurement system has continuously been acquiring data at 1 and 20 Hz/channel since the summer of 1998. A 40 m meteorological mast was built within the wind farm in the summer of 1999 in order to acquire relatively undisturbed wind speed data from 'free' sectors as well as to enable wake measurements. The mono pile and tower of one of the turbines are equipped with strain gauges at several depths ...
Approximately 62,000 lbs Fuel Load: 58,000 lbs. Type Fuel: JP4, JP5, JP8, JET A, JET A-1, JET B Standard Fuel Burn: 4500 - 6000 lbs/hr depending on altitude and airspeed Maximum...
The water permeability of tissues was investigated by measuring the efflux of 3HHO from previously loaded (in darkness) etiolated bean buds (Phaseolus vulgaris L. var. Red...Full Text Available
Samples of fat coal-E, its roof sandstone-A and blind coal-W from two coal mines in Hebei Province of China were brought to the laboratory to study the features of infrared thermal images and radiation temperature in the course of uni-axial load and uni-axial cycle load. To check the results of infrared remote sensing detection, two other methods, acoustic emission detection and electrical resistance detection were also used. The AGA-782 thermalvision detected change of the temperature field of the samples` surfaces. The study showed that: (1) coal rocks and sandstone in the course of loading have three types of infrared thermal image features and three types of infrared radiation temperature features; (2) infrared detection is comparable with acoustic emission detection and electrical resistance detection. Generally, the infrared forewarning of coal rocks` failure comes later than that of acoustic and electrical ...
The definition of “minor” veins in leaves is arbitrary and of uncertain biological significance. Generally, the term refers to the smallest vein classes in the leaf, believed to function...Full Text Available
In this report the effects of harmonics in marine power systems is discussed and a comparison is given between the most typical converter types, including pulse width modulated drives, load commutated inverters and cycloconverters. The effect of harmonic distortion on the power system equipment and loads is first briefly discussed. Special attention is given to the circumstances in the low voltage distribution system, where general load equipment is connected. In addition to the total harmonic distortion the effect of voltage deviation to the supply quality is also considered. The origin of harmonics in the load currents of the three converter types is then considered. The differences between the converters are outlined, and the most typical spectra are presented. The possible means for reducing the harmonic distortion are also studied. The solutions considered are the increasing of the short circuit ...
Background:Stem cells can differentiate into multiple cell types, and therefore can be used for cellular therapies, including tissue repair. However, the participation of stem cells...Full Text Available
This Health and Safety (HSE) document offers technical information on the design of foundations for supports in offshore installations, and relates particularly to the North Sea. It is based largely on guidance offered earlier in Section 20 of the Fourth Edition of the Health and Safety Executive's 'Offshore Installations; Guidance on Design, Construction and Certification', which was withdrawn in 1998. The document contains a general section on foundations and the rest of the document comprises sections on: (a) piled foundations (planning, problems, pile make-up, steel stresses, design of pile foundations, axial pile capacity, factors of safety for piled foundations, load-deflection of piles, and piles for tethered buoyant structures); (b) foundations for gravity structures (foundation types, loads and reactions during installation, operating loads and reactions, foundation problems, cyclic ...
Under a cooperative agreement, the Bureau of Mines, Magma Copper Co., and ASARCO, Inc., tested backfilled ground support systems at two elevations in Magma's San Manuel, AZ, mine. The tests were mainly for guidance in designing the loading crosscuts of th...
situ by isolating portions of the building envelope and performing tests .MAXIMUM ALLOWED LOAD ...and shall identify commissioning team members who will perform testing and prepare documentation.The commissioning agent may be
Electrical power is generated by steam turbines (steam being produced by coal, oil, gas or nuclear reactors), hydro units, gas turbines, internal combustion engines, jet engines, and pumped storage plants. Nuclear Power Plants generate only 15% of the total electrical power in the US. Nuclear Power Plants being cheaper to run are generally base loaded. The pumped-storage and gas turbine plants have ideal characteristics for peaking duty. In the pumping mode, pumped storage plants are used to provide additional system load and in the generating mode, they supply reactive power during peak load demands. Gas turbine plants have higher running costs, but are used as peaking units with a fast start capability. Fossil power plants need a minimum of 1 hour to stabilize expansion in the boiler and turbine generator. Due to a more competitive power supply market due to deregulation, most of the utilizes plan generation only for the ...
The dispersion mechanism of highly loaded coal-water mixture (CWM) in the presence of a polyelectrolyte additive was investigated. Two important factors have been found: the ability of the additive to apply a sufficient electric repulsive force to the coal particles, and an appropriate affinity of the additive to the coal surface.
A micro-mechanistic understanding of bone fracture thatencompasses how cracks interact with the underlying microstructure anddefines their local failure mode is lacking, despite extensive research nthe response of bone to a variety of factors like aging, loading, and/ordisease.
The effects of events which occur prior to slaughter, such as loading, transport, and holding at an abattoir, on the prevalence of Campylobacter species, including Campylobacter...Full Text Available
A numerical technique is developed for estimating water quality violation frequencies due to pollutant discharges from urban areas during combined sewer overflow events. The first four moments of in-stream pollutant concentration are found by integrating a pollutant loading - wat...
A new approach to dynamic security assessment in electric power systems is proposed. A power system is modeled as a dynamical system with random variable structure. Structural variations are caused by primary and secondary events. Primary events are state-independent disturbances representing line and unit faults and load changes and are modeled by random jump processes. Secondary events that represent forced line and unit outages and load sheddings are modeled through an aggregate representation of the protection system as random processes whose change in time corresponds to the crossing of switching surfaces by the state process. These switching surfaces are defined by the setting of the protective relays. Commensurate with this model a three-state decomposition of the operating conditions into normal, emergency, and partial load operating states is suggested. Transitions between these states are described in terms of ...
The hierarchical arrangement of collagen and mineral into bone tissue presumabley maximizes fracture resistance with respect to the predominant strain mode in bone. Thus, the ability of cortical...Full Text Available
Qualitative and quantitative aspects of the mechanisms involved in the regulation of cytoplasmic pH during an acid-load have been studied in Acer pseudoplatanus cells. Two main processes,...Full Text Available
BackgroundLeukocyte telomere length (LTL) is an emerging marker of biological age. Chronic inflammatory activity is commonly proposed as a promoter of ...Full Text Available
This report surveys the possibilities and restrictions of different construction materials for the purpose of the blades of a small stall regulated turbine. For example scaling up, material saving at decreasing of static or dynamic loads, comparisons of global costs based on prices per unit of weight, etc. For the mutual comparison of construction materials for turbine blades the starting point is a stall regulated horizontal axis turbine with a rotor diameter of 16 m and a tipvane speed of about 64 m/s. Short descriptions are given of the materials and of the applied production methods with the resulting blade geometry. The blade skins are dimensionized for storm loads after the optimalization of the blade geometry, needed for the design wind speed, is recorded. The resulting blade skins are mutually compared as for weight, mass inertia and bending stiffness. Also a comparison took place of the resulting reserve factors against ...
Urethral and endocervical swabs and self-collected vaginal swabs (SCVSs) and urine specimens are all used as samples for diagnosis of urogenital infection with Chlamydia trachomatis....Full Text Available
Failure of bone under monotonic and cyclic loading is related to the bone mineral density, the quality of the bone matrix and the evolution of microcracks. The theory of linear elastic fracture...Full Text Available
Pile foundations in several coastal and offshore structures are subjected to significant amounts of lateral loads due to wave action. Usually batter piles are adopted to resist large lateral loads. In this investigation an attempt has been made to study the behavior of batter pile in clayey soils through an experimental program carried out on instrumented model aluminium piles of 26 mm diameter in a test tank of size, 1,200 mm x 800mm x 1,100 mm. The pile was instrumented with electrical resistance type strain gauges to determine the bending moment variations along the depth of embedment of pile. Bending moment vis depth relationships were used to determine the Soil reaction (p) and lateral displacement (y) along the length of the pile for the applied load. From the bending moment vs depth curves it is found that depth of maximum bending moment is greater for negative batter pile than for vertical and positive batter pile. ...
A bedload trap in the riverbed provided direct quantitative measurement of debris-transport rate in the East Fork River, Wyoming, a basin of 466 km2 drainage area. Traction load moves only...Full Text Available
BackgroundKinematic and kinetic measurements used in laboratory settings can quantify upper extremity movement impairment following stroke, but their relationship...Full Text Available
The different radiation loads caused by natural and artificial radionuclides are compared in this paper. This examples will serve to illustrate that the problem of population exposure to radiation can only be solved in consideration of all components and to show which effects of the radiation from natural sources are of special importance in this connexion. (orig./AK).
Magnetic drug targeting, using core-shell magnetic carrier particles loaded with anti-cancer drugs, is an emerging and significant method of cancer treatment. Gold shell-iron core nanoparticles (Fe@Au) were synthesized by the reverse micelle method with aqueous reactants, surfactant, co-surfactant and oil phase. XRD, XPS, TEM and magnetic property measurements were utilized to characterize these core-shell nanoparticles. Magnetic measurements showed that the particles were superparamagnetic at room temperature and that the saturation magnetization decreased with increasing gold concentration. The anti-cancer drug doxorubicin (DOX) was loaded onto these Fe@Au nanoparticle carriers and the drug release profiles showed that upto 25% of adsorbed drug was released in 80 h. It was found that the amine (-NH2) group of DOX binds to the gold shell. An in vitro apparatus simulating the human circulatory system was used to determine the retention of these ...
179 cognitively healthy adults enrolled in the Sun Health Brain Donation program between 7/91 and 12/07 were at least 60 years old and nondemented at the time of death (21 had developed mild...Full Text Available
Cortical bone contributes the majority of overall bone mass and bears the bulk of axial loads in the peripheral skeleton. Bone metabolic disorders often are manifested by cortical microstructural changes...Full Text Available
BackgroundDuring normal breathing, the mesothelial surfaces of the lung and chest wall slide relative to one another. Experimentally, the shear stresses induced by...Full Text Available
...contribution of all diesel equipment on such section; (2) In the area of the section loading point if diesel haulage equipment is operated on the working section; (3) At a point inby the last piece of diesel equipment on the...
An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves in the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first. 14 figs.
This patent describes an automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves on the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first.
Pressurized fluidized bed combustion (PFBC) is an emerging coal-fired, combined-cycle power generation technology nearing commercial status through several operating and planned demonstration plants throughout the world. Current-generation PFBC plants use ``ruggedized`` gas turbines that can tolerate dust loading common with conventional cyclone gas cleaning. The next generation of PFBC will apply advanced hot gas cleaning systems that will reuse the dust loading to low levels acceptable to high performance, industrial gas turbines. These advances should result in performance and cost advantages. This article examines the demonstration of PFBC technology at Tidd power station.
Design methods and parameters are described which are addressed when considering consequences of a postulated pipe rupture event in a nuclear plant design. Parameters discussed are break opening time and size, resultant blowdown characteristics of the effluent from the broken pipe, jet reaction and impingement loading, pipe motion, and pipe impact loading on steel and concrete structures. The impact the various parameters have on overall plant designs and conservatisms inherent in each consideration are evaluated in a qualitative nature. Finally, recommendations are provided for each parameter discussed for further evaluation and study.
A prototype hydride storage bed, using LaNi{sub 4.25}Al{sub 0.75} as the storage material, was fitted with strain gages to measure strains occurring in the stainless steel bed vessel caused by expansion of the storage powder upon uptake of hydrogen. The strain remained low in the bed as hydrogen was added, up to a bed loading of about 0.5 hydrogen to metal atom ratio (H/M). The strain then increased with increasing hydrogen loading ({approximately} 0.8 H/M). Different locations exhibited greatly different levels of maximum strain. In no case was the design stress of the vessel exceeded.
The layout of the network with its frequency and transmission power control shows how the time behaviour of power plants and consumers determines the frequency curve during sudden power disturbances. As for switching processes in the network for the turbine, network operation entails loads due to shock-like disturbance functions to which one should not normally respond by switching off. The interception controllers are therefore adjusted via a simulation model by which the vibrations of the turbine rotor can be modelled in real time under different network loads. (GL).
The risk analysis was carried out in consideration of conditions prevailing at the Kalkar site analogous to the investigations in phase A of DRS (German Reactor Study). Earthquake design loads include the probabilities of upper deviations of the site intensities to be expected. The calculations of dynamic loads for select buildings are made using models and computational methods. Component analyses were performed analogous to DRS for the supports of large components, supports of the roof construction of the reactor building taking into account support reserves due to plastic work capacity, wall disks in steam generator buildings and switchboard plant buildings. (DG).
The general types of pumped-storage plants and considerations for determining their need, use, and selection are presented. A brief discussion of TVA's experience on two pumped-storage schemes is included. Pumped-storage plants have become an integral part of many hydropower systems. Most of these systems use pumped-storage plants to meet power requirements during the peak load demands. In any application, large or small, the expected load demand and supply source must be identified to select the best scheme required for the particular system.
Simplified strain-based fracture mechanics equations, established for external surface cracked pipelines subjected to an external bending load, are presented and used in probabilistic assessment of a pipeline girth weld. The model takes into account several parameters, such as variation in crack depth, crack length, internal pressure and material hardening. The critical strain from ductile tearing in the cracked pipeline is found by using the tangency criterion. The reliability problem is solved using first and second order reliability methods for different pipe dimensions and load levels.
A method for cleaning timing optimization in a parallel steam generator system is described. The method is based on the minimization of a suitable objective function, and takes into account the load allocation on steam generators. In order to establish appropriate fouling growth models the mechanism of the particle deposition and removal on heat transfer surfaces is analyzed. The objective function is related to the short time management costs which are based on depreciation of steam generators, fuel costs and the costs of cleaning interventions. The optimization problem is described; a direct one level method is compared with a two level method. Some applications and their results are reported and discussed. (author)
This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.
This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.
In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.
This invention concerns a hydraulic braking system for loads subjected to impacts and vibrations. These double acting telescopic type hydraulic braking systems possess significant drawbacks linked to possibly important hydraulic leaks due to (a) the use of many dynamic seals in such appliances and (b) the effects of the environment of the system on these seals, particularly when employed in nuclear power stations where the seals reach significant temperatures and are subjected to radiation. Under this invention a remedy is suggested to such drawbacks by integrating means to offset automatically the leaks and the accumulation of hydraulic fluid expansions, as well as facilities to show if such leaks have occurred.
The present paper dealt with the extension of tendon friction coefficient correlation as a function of loading end load and circumferential angle, proposed in the former paper. The extended correlation further included the effects of the number of strands contacted with sheath, tendon diameter, politicization of tendon and tendon local curvature. The validity of the correlation was confirmed by several published measured data. The structural analysis of middle cylinder part of 1/4 PCCV (Prestressed Concrete Containment Vessel) model was conducted using the present friction coefficient correlation. The results were compared with the analysis using constant friction coefficient, focused on the tendon tension force distribution. (author)
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a {sup 60}Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used.
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a "6"0Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used.
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a "6"0Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used. (author)
Fastening systems for parts that endure high vibration shear loads have traditionally been difficult or expensive to produce. This application describes a fastening system with multiple conical surfaces and eccentric offsets. The novel conical fastener system allows parts to be assembled with reduced tolerance controls at interface features while improving alignment precision. The eccentric conical fastening system is particularly well suited for assemblies with high shear loads in high vibration/shock environments, and/or for systems that have extremely precise pointing requirements.
The data center in this study had a total floor area of 3,024 square feet (ft{sup 2}) with one-foot raised-floors. It was a rack lab with 147 racks, and was located in a 96,000 ft{sup 2} multi-story office building in San Jose, California. Since the data center was used only for testing equipment, it was not configured as a critical facility in terms of electrical and cooling supply. It did not have a dedicated chiller system but was served by the main building chiller plant and make-up air system. Additionally it was served by only a single electrical supply with no provision for backup power in the event of a power outage. The Data Center operated on a 24 hour per day, year-round cycle, and users had full-hour access to the data center facility. The study found that data center computer load accounted for 15% of the overall building electrical load, while the total power consumption attributable to the data center including allocated cooling ...
SnO{sub 2}-carbon nanotube (CNT) composite sheets are synthesized using poly(vinylpyrrolidone) to uniformly load a monolayer of SnO{sub 2} nanoparticles onto the surfaces of CNTs and CNT bundles within cross-stacked CNT sheets. When they are used as high-capacity (over 850 mA h g{sup -1}) and binder-free anodes in rechargeable lithium-ion batteries, they exhibit good cycle performance. (Abstract Copyright [2009], Wiley Periodicals, Inc.)
The CASTOC project addresses environmentally assisted cracking (EAC) phenomena in low alloy steels used for pressure boundary components in both Western type boiling water reactors (BWR) and Russian type pressurised water reactors (VVER). It comprises the four work packages (WP): inter-laboratory comparison test (WP1); EAC behaviour under static load (WP2), EAC behaviour under cyclic load and load transients (WP3); evaluation of the results with regard to their relevance for components in practice (WP4). The use of sophisticated test facilities and measurement techniques for the on-line detection of crack advances have provided a more detailed understanding of the mechanisms of environmentally assisted cracking and provided quantitative data of crack growth rates as a function of loading events and time, respectively. The effect of several major parameters controlling EAC was investigated with ...
With the compensator-series equipment put into operation in 1992 - giving a performance of 330 Mvar - it was made possible for high-performance electronics to use a continuously variable, fully loaded power transmission line and to regulate the energy flow and minimise overcurrent losses. As well as these technical qualities, this system could offer environmental advantages for European implementation. This would avoid the need to plan and construct new high voltage transmission lines in order to meet increased demand. (orig.)
The compressive and torsional buckling behavior of carbon nanotube bundles at room temperature is examined with classical molecular dynamics simulation. The critical compressive load and stiffness of a single carbon nanotube in the bundle are found to be similar to those of individual carbon nanotubes. However, the critical torsional moment and stiffness of a single carbon nanotube in the bundle are found to be higher than those of individual carbon nanotubes. In addition, this study demonstrates that van der Waals interactions between the nanotubes in the bundle significantly affect the critical compressive load of the nanotube bundle.
A concept of a traveling wave direct energy converter (TWDEC) is developed for 14.7-MeV fusion protons based on the principle of a backward wave oscillator. Separation of fusion protons from thermal ions is accomplished by using ExB ion drift. Energy conversion rate up to 0.87 is attained by applying three-stage modulation of the proton beam. A one-dimensional particle-circuit code is developed to examine self-excitation of the traveling wave and its stability under loading. Electrostatic wave with a fixed frequency is excited spontaneously, and stability of the wave is ensured under loading. (author).
In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil.
The effect of interfacial structure on the mechanical properties of aluminum-ceramic composite materials fabricated by liquid phase sintering was studied. The composites were based on two matrix alloys (powder metallurgy alloys 201 and 601) reinforced with either Al{sub 2}O{sub 3} or SiC particulate. Characterization of the interfacial regions demonstrated that the SiC-matrix interfaces were faceted whereas the Al{sub 2}O{sub 3}-matrix interfaces had an incomplete layer of a silicon-rich amorphous phase. Preferential attack of the particles during sintering is believed to cause the crystallographic facets to form on SiC. Locally high silicon concentrations near Al{sub 2}O{sub 3} particles led to the formation of a glassy phase from the reduction of Al{sub 2}O{sub 3}. The difference in interfacial structure resulted in a higher particle-matrix bond strength and therefore improved composite mechanical properties in the SiC-reinforced materials compared with the ...
Sensors installed at a telephone office building in Neenah, WI, continuously monitor 24 parameters related to the operation of the building's heating, ventilating, and air conditioning (HVAC) system. This data is stored in a dedicated minicomputer and can be retrieved, in various formats, for subsequent analyses. For more than a year, we have measured indoor and outdoor concentrations of both fine and coarse airborne particles, their chemical constituents, and volatile organic compounds at this same location. Using this data, we have examined the composition of the indoor air as it correlates to the composition of the outdoor air and the various HVAC operating parameters. The steady-state indoor concentrations of the particles, particulate constituents, and organic vapors can be explained in the context of a mass balance model. This model can also be used to calculate the rate at which selected chemicals are generated within the building, as well as to ...
This paper presents the history and objectives of the development of a standard method for the measurement of organic contaminants in biomass producer gases. Recently, a project with that title has started in the European 5{sup th} Framework Programme. The structure of this project with acronym 'Tar Protocol' is also described in this paper. The project is performed by 17 partners and continues earlier work initiated by IEA (International Energy Agency), DoE (Department of Energy) and EU (European Union) in 1998. The project aims to combine two draft Protocols that resulted from this earlier work. The Tar Protocol will be developed for accurate measurement of organic contaminants ('tars') over a large range of concentrations (1 mg/Nm{sup 3} to 100 g/Nm{sup 3}) and conditions (0 - 900 deg C; 0.9 - 60 bars). Besides, a particulate concentration will be determined too. Together with the Protocol comes a number of accepted ...
The search for alternative energy supplies continues since the oil crisis of 1973. One energy vector is dihydrogen, H_2. Of the group VI hydrides, water has been the focus of most studies in harnessing solar energy and generating H_2. Two basic photochemical strategies have been employed: molecular photocatalytic systems, and semiconductor based photocatalytic systems. The results have not met with the euphoric expectations of the mid-1970's because of the difficulties encountered in H_2O splitting (E"0 S"2 "-/S = + 0.51 eV, NHE) is another vehicle tapped as a potential source of H_2. Heterogeneous photocatalysis utilizing semiconductor particulates and sunlight as the photon source has been successful with interesting quantum efficiencies. To this end, novel photocatalytic devices have been developed; one of these uses two coupled semiconductors to achieve vectorial displacement of the photogenerated reducing and oxidizing equivalents. An important area in which ...
This document provides details on a $120.2 million package of initiatives to implement the Ozone Annex, an agreement signed in December 2000 between Canada and the United States to significantly reduce transboundary smog causing pollutants and to improve air quality. Taking action under the Ozone Annex will address health and environmental challenges by reducing emissions of nitrogen oxides and volatile organic compounds which are precursors to ground-level ozone. This document described the actions that will be taken by the Government of Canada to reduce emissions from vehicles and the fuels that power them. It also described the measures that will be taken to improve air quality monitoring networks. The National Pollutant Release Inventory will be used to meet new reporting commitments contained in the Annex. This document also highlights the initial actions that will be taken to reduce pollution from industrial sources and products. Some of the major initiatives already launched ...
There has been considerable interest in producing and studying nanoparticle materials because of the effect of size on their structure, physical and chemical structure. Most studied nanoparticle semiconductors belong to the II-VI group, as they are relatively easy to synthesize and are generally prepared as particulates or in thin film form. Among II-VI compounds, CdS is one of the most studied materials. There are different ways to synthesize CdS nanoparticles such as colloidal particles, chemical decomposition, sol-gel, gas evaporation, magnetron sputtering, electrostatic deposition, and etc. {gamma}-irradiation is one of the effective methods for synthesis of nanomaterials. These nonomaterials have been extensively used in the preparation of nanocrystalline metals, metal oxides, and metal-polymer composites. However, The preparation of CdS nanoparticle and CdS/ polyacrylonitrile nanocomposite by {gamma}-irradiation method at room temperature and ambient ...
In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR (formerly Kellogg Brown & Root) Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results gasification operation with Illinois Basin bituminous coal in PSDF test campaign TC17. The test campaign was completed from October 25, 2004, to November 18, 2004. System startup and initial operation was accomplished with Powder River Basin (PRB) subbituminous coal, and then the system was transitioned to Illinois Basin coal operation. The major objective for this test ...
The association of Finnish Plastics Industry examined the possibilities to utilize energy content of plastic wastes in spring 1990. A bark fuelled boiler plant of forest industry was used as test power plant. The power of the plant was 60 Mw. This report discusses shortly the theory of combustion of plastics. About 130 000-15 000 tons of plastic waste, corresponding to 7 % of the solid municipal waste, is dumped annually in Finland. Utilization of the plastic waste recovered from municipal wastes for energy production is technically viable in present power plants among present energy production. The chipping and mixing of the plastic in the other fuel are the only pretreatment required for the plastic waste. In Finland there are several power plants using suitable fuels for plastic mixture combustion. The portion of the plastic of the total fuel power was 10 %. No problems occurred during the tests. The results of the tests are presented in this report. Special attention has been paid ...
This paper presents the results of a study carried out at three sites in Madurai, India in order to assess ambient air quality levels and their impact on public health in urban areas. Indicators of public health were sought through primary and secondary health data and blood lead concentrations of male and female inhabitants and shopkeepers. Lean concentrations in blood samples were examined according to distance from the road, age, smoking status, hours of stay per day in the city, and period of stay in years in Madurai. Ambient air quality level indicators included the level of gaseous and particulate pollution using Central Pollution Control Board standard estimation methods. Observed atmospheric conditions across the three sites are examined according to mean solar insolation, mean temperature, mean relative humidity and mean wind velocity. The study concluded that pollution abatement measures must be implemented to safeguard public health in Madurai. 5 refs., ...
Tests with a 61 cm diameter fluidized-bed combustor revealed that raw cotton gin trash could be efficiently burned while satisfying Federal standards for particulate emissions. Certain chemicals within cotton gin trash zone can cause slagging or caking of ash and bed particles in the combustion zone. They can also corrode and accumulate on the heat recovery equipment. These problems are not considered insurmountable and methods of control are being studied. Raw cotton gin trash was also converted into a low Btu gas using fluidized-bed technology. Tests with a 30 cm diameter gasifier revealed that raw gin trash could be converted to a combustible gas, containing carbon monoxide and hydrogen. The heating value of the gas ranged from 3.65 to 5.29 MJ/m3 and about 50 percent of the heat value of the raw trash was converted to combustible gases. Economic analyses have shown that these techniques can be economically competitive with present fuels in specific situations.
Working in partnership with industry, the US Department of Energy`s (DOE`s) Office of Industrial Technologies (OIT) is helping reduce industrial energy use, emissions, and waste while boosting productivity. Operating within the Office of Energy Efficiency and Renewable Energy (EE), OIT conducts research, development, demonstration, and technology transfer efforts that are producing substantial, measurable benefits to industry. This document summarizes some of the impacts of OIT`s programs through 1997. OIT tracks energy savings as well as other benefits associated with the successfully commercialized technologies resulting from OIT-supported research partnerships. Specifically, a chart shows current and cumulative energy savings as well as cumulative reductions of various air pollutants including particulates, volatile organic compounds (VOCs), nitrogen oxides (NO{sub x}), sulfur oxides (SO{sub x}), and the greenhouse gas, carbon dioxide (CO{sub 2}). The bulk of ...
As part of the 1999 NARSTO Northeast Oxidant and Particulate Study (NE-OPS) field campaign, the DOE G-1 aircraft sampled trace gases and aerosols in and around the Philadelphia metropolitan area. Twenty research flights were conducted between July 25 and August 11. The overall goals of these flights were to obtain a mechanistic understanding of O(sub 3) production; to characterize the spatial and temporal behavior of photo-oxidants and aerosols; and to study the evolution of aerosol size distributions, including the process of new particle formation. Within the NE-OPS program, other groups provided additional trace gas, aerosol, and meteorological observations using aircraft, balloon, remote sensing, and surface based instruments (Phillbrick et al., 2000). In this article we provide an overview of the G-1 observations related to O(sub 3) production, focusing on the vertical distribution of pollutants. Ozone production rates are calculated using a box model that is ...
This report is an assessment of emission-control costs for municipal-waste combustors (MWCs). The details of the cost estimates, including their development, components, and cost premises, are addressed. A model-plant approach was used in the sizing and costing of the emission control systems. Due to differences in the feed-waste characteristics, combustion parameters, and emissions, separate cost estimates were required for mass burning (MB), modular (MOD), refuse-derived fuel (RDF), and fluid-bed combustion (FBC) type furnaces. Cost estimates were developed for control of particulate matter (PM) emissions only and for control of both acid gas and PM emissions from the MWC model plants. Controlled PM emission levels of 0.03, 0.02, and 0.01 gr/dscf, corrected to 12% CO/sub 2/, and 90 and 70% reductions of HC1 and SO2, respectively, were used to develop the control cost estimates. Costs were developed using the cost information received from a number of ...
The contamination of environmental materials (soil and dust) by heavy elements is of concern in assessing environmental pollution. Characterization of samples is performed in order to provide information that can be used to assess the potential hazard of the material, to assess remediation strategies, and to determine the source of the heavy element-bearing material. Microbeam analysis using a scanning electron microscope (SEM) or electron microprobe on polished particle mounts allows the size, internal morphology and chemical composition to be determined on a particle-by-particle basis. Computer controlled SEM allows all factors except internal structure to be acquired in an automated fashion. The authors present examples of two studies using microbeam techniques. In the first example, they illustrate how cadmium associated with sphalerite in soils can be quantified at levels down to a few parts per million (ppm) using computer controlled SEM techniques. In the second example, they ...
Carbonaceous solid material such as coal is gasified in a fast fluidized bed gasification system utilizing dual fluidized beds of hot char. The coal in particulate form is introduced along with oxygen-containing gas and steam into the fast fluidized bed gasification zone of a gasifier assembly wherein the upward superficial gas velocity exceeds about 5.0 ft/sec and temperature is 1500.degree.-1850.degree. F. The resulting effluent gas and substantial char are passed through a primary cyclone separator, from which char solids are returned to the fluidized bed. Gas from the primary cyclone separator is passed to a secondary cyclone separator, from which remaining fine char solids are returned through an injection nozzle together with additional steam and oxygen-containing gas to an oxidation zone located at the bottom of the gasifier, wherein the upward gas velocity ranges from about 3-15 ft/sec and is maintained at 1600.degree.-200.degree. F. temperature. This ...
The successful development of coal-fired combined cycle power generation systems require that all component parts are manufactured from appropriate materials and that these materials give predictable in-service performance. High temperature corrosion resulting from coal-derived particulates, deposition and gaseous species, is potentially life limiting for many components in these systems. Realistic laboratory test methods are outlined for gasifier and gas turbine environments and these have been combined with a materials assessment method based on accurate dimensional metrology. Such tests have allowed the production of models of materials performance as well as accurate comparisons between laboratory and plant derived data. These initial models predict the performance of materials well in the gas turbine environment, but tend to under-predict the damage observed in real gasifier environments. The differences found between materials performances observed in real ...
Processing of food with ionizing radiation is a method suitable to enhance shelf-life and hygienic quality. Up to a dose of 10 kGy the method is considered wholesome. In many countries the practical use of food irradiation is increasing, however, in the Federal Republic of Germany the process is strictly forbidden. Applications and methods for radiation processing of food are compiled, limits and prospects are explained, and advantages and disadvantages are compared with traditional methods. Identification of irradiated foods and dosimetry and process control for radiation processing of food are areas where further research is needed. Continuous processing of particulate foods in bulk is an application where electron accelerators might be profitable. Beam parameters and velocity distribution of food particles in the treatment area can be matched for an effective result. Thus, dose distribution can be adjusted for homogeneous treatment and at the same time radiation ...
Mechanisms that govern transport, accumulation and toxicity of persistent pollutants at interfaces in aquatic ecosystems were the foci of this thesis. Specific attention was paid to humic substances, their occurrence, composition, and role in exchange processes across interfaces. It was concluded that: The composition of humic substances in aquatic surface microlayers is different from that of the subsurface water and terrestrial humic matter. Levels of dissolved organic carbon (DOC) in the aquatic surface microlayer reflect the DOC levels in the subsurface water. While the levels and enrichment of DOC in the microlayer generally show small variations, the levels and enrichment of particulate organic carbon (POC) vary to a great extent. Similarities exist between aquatic surface films, artificial semi-permeable and biological membranes regarding their structure and functioning. Acidification and liming of freshwater ecosystems affect DOC:POC ratio and humic ...
Advanced coal-fired combined-cycle power systems under development and demonstration have the potential to increase generating efficiency to approach 50%, reduce the cost of electricity by up to 20%, and meet stringent standards on emissions of SO{sub x}, NO{sub x}, fine particulates, and air toxic metals. Integrated gasification combined cycle, pressurized fluidized-bed combustion, and externally fired combined cycle systems rely on different high-temperature combinations of heat exchange, gas filtration, and sulfur capture to meet these requirements. The success of these systems when operated on low-rank coals depends importantly on the behavior of the ash. This paper focuses on the behavior of ash in an intermediate-scale transport gasifier coupled with a hot-gas cleanup system. The work reported is part of the overall program on hot-gas cleanup and the transport reactor development unit (TRDU) located at the Energy and Environmental Research Center (EERC), ...
The size of the market for pulverized activated charcoal and particulate activated charcoal prepared by the Association of Inorganic Chemicals of Japan is 55,000t/y (1987) in total. Individually, some fields showed the expansion such as water purification, water treatment and gas treatment on the one hand, but on the other hand, several fields showed the decline such as sugar refining, dextrin sugar and soda glutamate. As a whole, the market showed no marked fluctuations or a very slight increase. Many of the above usages are traditional in the chemical industry and the food industry, etc., and the new usages developed in the past several years have not grown to influence the statistics as yet. Selection of raw material is the key for determining the character of activated charcoal. And the factors of determining the characteristic features are fine pore, surface area and surface activity (catalystic activity). Furthermore, the function requirement from the ...
Los Alamos National Laboratory is subject to annual emissions-reporting requirements for regulated air contaminants under Title 20 of the New Mexico Administrative Code, Chapter 2, Part 73 (20.2.73 NMAC), Notice of Intent and Emissions Inventory Requirements. The applicability of the requirements is based on the Laboratory's potential to emit 100 tons per year of suspended particulate matter, nitrogen oxides, carbon monoxide, sulfur oxides, or volatile organic compounds. For calendar year 2001, the Technical Area 3 steam plant was the primary source of criteria air pollutants from the Laboratory, while research and development activities were the primary source of volatile organic compounds. Emissions of beryllium and aluminum were reported for activities permitted under 20.2.72 NMAC. Hazardous air pollutant emissions from chemical use for research and development activities were also reported.
In this study, the exhaust gas from a common-rail direct injection diesel engine was investigated both upstream and downstream warm-up catalytic converters (WCC). Three different types of ultra-low sulfur fuels (ethanol-diesel blend, ethanol-diesel blend with cetane improver and pure diesel) were tested in this study. The objective of the work was to study the engine performance and the formation of THC (total hydro carbon), CO (carbon monoxide), NO{sub x} (nitrogen oxides), smoke and PM (particulate matters) when using these fuels. THC and CO emissions of the ethanol-diesel blend fuels were slightly increased, and about 50-80% mean conversion efficiencies of THC and CO on catalysts were achieved in the ECE R49 13-mode cycle. Smoke was decreased by more than 42% in the entire ECE 13-mode cycles. From the measurement of scanning mobility particle sizer (SMPS) for the particle size range of 10-385 nm, the total number and total mass of the PM of the ethanol-diesel ...
The concept of oxygen enriched air applied to reciprocating engines is getting renewed attention in the context of the progress made in the enrichment methods and the tougher emissions regulations imposed on diesel and gasoline engines. An experimental project was completed in which a direct injection diesel engine was tested with intake oxygen levels of 21% -- 35%. Since an earlier study indicated that it is necessary to use a cheaper fuel to make the concept economically attractive, a less refined fuel was included in the test series. Since a major objection to the use of oxygen enriched combustion air had been the increase in NO{sub x} emissions, a method must be found to reduce NO{sub x}. Introduction of water into the engine combustion process was included in the tests for this purpose. Fuel emulsification with water was the means used here even though other methods could also be used. The teat data indicated a large increase in engine power density, slight improvement in thermal ...
DF (decontamination factor) of two types of air filter was investigated against /sup 198/Au aerosol particles with AMAD (activity median aerodynamic diameter) = 1.2 ..mu..m and sigmag (geometric standard deviation) = 2.0. One of the filters, SO filter, is HEPA (high efficiency particulate air) filter media with 46 mmphi, and the other is HE-40T (cellulose-glass fiber filter for dust sampling) filter media with 40 mmphi. DF of the SO filter was found to be over 5 x 10/sup 4/ at air flow rate of 1 lmin. And DF of HE-40 T filter was determined to be 94+-4 at the same airflow rate. In the multistage HE-40 T filter system, DF decreased at each succeeding stage. It was confirmed by numerical simulation that the decrease of DF was not inconsistent with the decrease of collection performance in each successive filter. It was also confirmed that DF could be predicted by the numerical simulaiton, if particle penetration function of filter and size distribution function of ...
DF (decontamination factor) of two types of air filter was investigated against "1"9"8Au aerosol particles with AMAD (activity median aerodynamic diameter) = 1.2 #mu#m and #sigma#g (geometric standard deviation) = 2.0. One of the filters, SO filter, is HEPA (high efficiency particulate air) filter media with 46 mm#phi#, and the other is HE-40T (cellulose-glass fiber filter for dust sampling) filter media with 40 mm#phi#. DF of the SO filter was found to be over 5 x 10"4 at air flow rate of 1 l/min. And DF of HE-40 T filter was determined to be 94#+-#4 at the same airflow rate. In the multistage HE-40 T filter system, DF decreased at each succeeding stage. It was confirmed by numerical simulation that the decrease of DF was not inconsistent with the decrease of collection performance in each successive filter. It was also confirmed that DF could be predicted by the numerical simulaiton, if particle penetration function of filter and size distribution function of ...
ATLAS is one of the four experiments which will take place at the LHC, the CERN future protons collider. This accelerator, which should start in 2007, will allow to continue the studies carried out by its predecessors, as the standard model Higgs boson and new physics searches. The very high luminosity -10 fb{sup -1} during the first three functioning years, then 100 fb{sup -1}- and the 14 TeV in the frame center will ease these studies. The Centre de Physique des Particules de Marseille took part in the ATLAS collaboration, taking in charge half of the End-cap electromagnetic calorimeter modules construction. The description of this sub-detector and the construction steps, in particular the electrical tests which allow the stacking validation, are presented in this document. These tests results, obtained for the live first production modules, are analysed. The pre-series module (module 0) performances, obtained with beam tests performed at CERN in 1999, are also ...
The EPA proposed air emission guidelines for existing Municipal Waste Combustion (MWC) facilities on December 20, 1989. The regulation, 40 CFR Subpart Ca, was eventually issued on February 11, 1991, but Section 129 of the Clean Air Act Amendments of 1990 required the EPA to review and revise the regulations. On October 31, 1995, Subpart Ca was withdrawn and replaced by a more stringent regulation, 40 CFR Subpart Cb. The new guidelines apply to all existing MWC facilities for which construction began before September 20, 1994 and have a capacity to combust over 35 megagrams per day. Most facilities will be required to be in compliance with the new regulations four years from the date Subpart Cb was issued, or by December 19, 1999. Subpart Cb requires significant capital expenditures and increases in operating costs. The major modifications EPA based the guidelines on are summarized. Pollutants of concern include sulfur dioxide, hydrochloric acid, dioxin/furans, metals, ...
It is very important in a nuclear air cleaning system that HEPA (High Efficiency Particulate Air) filter is for reduction of releasing amounts of airborne radioactive particles. HEPA filter, by definition, has a minimum collection efficiency of 99.97 % for 0.3 #mu#m particles. However, DF (Decontamination Factor), which is necessary for safety management, can not be directly derived from the efficiency. And the current standard defined for 0.3 #mu#m particles has no scientific justification, because it has been found that the most penetrating particle size through HEPA filter is not always 0.3 #mu#m. In the present paper, a numerical experiment was made in order to estimate a relationship between DF and the efficiency. And new standard, in which the minimum DF is able to be easily obtained, was proposed. In the multistage filtration system, it was found that lower values of DF was possible to be experimentally indicated in the second and the third stages, even if ...
This study analyzed the atmospheric emissions produced by the live firing of a 155 mm Howitzer gun. The study was conducted during a live firing training exercise at a Canadian Forces Base. Air emissions were sampled continuously for 3 hours. Particles and chemicals were accumulated on sampling media during the firing of 69 rounds. A single round was fired using 4 bags of propellants, and an additional 3 rounds were fired using 5 bags of propellant. Samples included particulate matter; hydrogen cyanide; polycyclic aromatic hydrocarbons (PAHs); dinitrotoluene compounds; benzene; toluene; ethylbenzene; xylene; metals; aldehydes; nitric acid; nitric oxide; nitrogen dioxide; hydrogen sulphide; and sulphur dioxide. Samples were collected at 8 m to the left of the gun as well as at 22 m in front of the gun muzzle in the line of fire. Results of the study showed that 60 per cent of the particles were below 10 {mu}m. Formaldehyde concentrations of 7.1 and 3.6 {mu}g/m{sup ...
This study was undertaken to collect emissions performance data for Canadian and comparable American refineries. The objective was to examine parameters that affect refinery air emissions performance and develop methods or correlations to normalize emissions performance. Another objective was to correlate and compare the performance of Canadian refineries to comparable American refineries. For the purpose of this study, benchmarking involved the determination of levels of emission performance that are being achieved for generic groups of facilities. A total of 20 facilities were included in the benchmarking analysis, and 74 American refinery emission correlations were developed. The recommended benchmarks, and the application of those correlations for comparison between Canadian and American refinery performance, were discussed. The benchmarks were: sulfur oxides, nitrogen oxides, carbon monoxide, particulate, volatile organic compounds, ammonia and benzene. For ...
Laser devices are currently in widespread use in particular by armed forces for different tasks. Electro-optical sensors as well as unprotected human eyes are extremely sensitive to laser radiation and can be permanently damaged from direct or reflected beams. Laser damage depends on the interaction between the laser beam and the atmosphere in which it traverses. The atmospheric conditions, including the range, terrain features, turbulence, and atmospheric particulates, may alter the laser's effect on different electro-optical devices and systems. When a laser beam passes through the atmosphere the optical turbulence affects the beam. As a result, temporal intensity fluctuations (scintillations) or spatial variations in intensity within a beam cross-section occur. Atmospheric scintillations pose a safety problem because an observer or sensor can be subjected to the risk of a localized irradiance (local focusing effect) much greater than that which would occur in a ...
The DOE is conducting a comprehensive technical analysis of a flexible-fuel transportation system in the United States -- that is, a system that could easily switch between petroleum and another fuel, depending on price and availability. The DOE Alternative Fuels Assessment is aimed directly at questions of energy security and fuel availability, but covers a wide range of issues. This report examines environmental, health, and safety concerns associated with a switch to alternative- and flexible-fuel vehicles. Three potential alternatives to oil-based fuels in the transportation sector are considered: methanol, compressed natural gas (CNG), and electricity. The objective is to describe and discuss qualitatively potential environmental, health, and safety issues that would accompany widespread use of these three fuels. This report presents the results of exhaustive literature reviews; discussions with specialists in the vehicular and fuel-production industries and with Federal, State, ...
Simultaneous reduction of NO{sub x} and particulate emissions in a direct-injection diesel engine has been realized experimentally with a high squish combustion chamber. The purpose of this study is to investigate the effects of high squish combustion chamber on combustion process in detail. Engine CFD code FREC was used for the analysis. The results show the followings. (1) Compared with standard toroidal chamber, high squish chamber generates high turbulence due to strong squish and large expansion flow is caused in the cavity. (2) Rich and high-turbulence combustion, which forms ring area in the cavity under squish lip, continues during the combustion. (3) The high squish combustion chamber keeps fuel long in the cavity and less hid spreads out to the cold clearance volume. (4) For the condition of retarded injection timing, the effect of high squish is mainly observed at initial combustion and high swirl is more effective at diffusion combustion. (author)
Maternal exposure to ambient air pollution has increasingly been linked to adverse pregnancy outcomes. The evidence linking this exposure to congenital anomalies is still limited and controversial. This case-control study investigated the association between maternal exposure to ambient particulate matter with aerodynamic diameter less than 10 ?m (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxide, nitric oxide (NO), ozone (O(3)), and carbon monoxide (CO) and the occurrence of congenital heart disease in the population of Northeast England (1993-2003). Each case and control was assigned weekly average (weeks 3-8 of pregnancy) of pollutant levels measured by the closest monitor to the mother's residential postcode. Using exposure as both continuous and categorical variables, logistic regression models were constructed to quantify the adjusted odds ratios of exposure to air pollutants and the occurrence of each outcome group. We found exposure to CO and NO to be ...
The adsorption of mercury vapor on particles was studied by using soot particles generated by incineration of sewage sludge (EP-ash) and activated carbon particles. Through the experiments, it was found that, at 298 K, the EP-ash has a fairly high adsorption capacity for mercury vapor in the order of 10/sup -6/g/g, which is between that of the ordinary soils and that of activated carbon particles. Furthermore, it was found that physical adsorption of mercury vapor on the studied particles at high temperature is described by Dubinin's equation. On the basis of the equation, it was shown that EP-ash physically adsorbs very little mercury at high temperature, and therefore, most mercury in the EP-ash is chemically adsorbed or contained in a form of mercury compounds. Nevertheless, the total amount of mercury contained in the particles is very little compared to the total mercury in the exhaust gases so that most mercury behaves as a vapor in the presence of ...
Improved test techniques are needed for evaluating the inherent stability of middle distillate fuels both in surveillance and in procurement activities. A project was initiated to define and evaluate the contributing conditions leading to the formation of deleterious products in accelerated aging tests of middle distillate fuels and to relate these results to an experimental definition of more repeatable/reliable middle distillate fuel stability test technique(s). A literature search was conducted to provide a list of stability test techniques and their interpretations which could be used in a correlative middle distillate fuel stability test program. For this program, seven accelerated stability tests were chosen and evaluated using a set of six test fuels. The test techniques were selected to represent a wide variety of test conditions, including temperature, aging time, and oxygen availability. These six test fuels were purposely chosen to represent a wider range of stabilities than ...
Biomass and nutrient dynamics of black spruce seedlings during the hardening phase of the greenhouse rotation were examined after four pre-hardening fertilization regimes - conventional, constant-rate loading, exponential loading, and high exponential loading (delivering respectively 15, 40, 40 and 60 mg N seedling{sup -1}) - in order to assess nutrient dilution and steady-state nutrition. Although height growth of seedlings had virtually ceased during hardening, shoot biomass increased 99-142% and root biomass increased five- to tenfold depending on treatment. The biomass increase compromised steady-state nutrient status by diluting internal nutrient pools as nutrient supply was unable to keep up with growth. Soil nutrient levels were rapidly depleted during this period because of plant uptake and lack of fertilizer supplementation. Pre-hardening nutrient loading partly countered and delayed dilution ...
Some motor operated valves now have higher torque switch settings due to regulatory requirements to ensure valve operability with appropriate margins at design basis conditions. Verifying operability with these settings imposes higher stem loads during periodic inservice testing. These higher test loads increase stresses in the various valve internal parts which may in turn increase the fatigue usage factors. This increased fatigue is judged to be a concern primarily in the valve disks, seats, yokes, stems, and stem nuts. Although the motor operators may also have significantly increased loading, they are being evaluated by the manufacturers and are beyond the scope of this study. Two gate valves representative of both relatively weak and strong valves commonly used in commercial nuclear applications were selected for fatigue analyses. Detailed dimensional and test data were available for both valves from previous studies ...
This paper describes the design of a test rig, which is used to apply a representative pressure load to a full-scale composite sandwich secondary aircraft structure. A generic panel was designed with features to represent those in the composite sandwich secondary aircraft structure. To provide full-field strain data from the panels, the test rig was designed for use with optical measurement techniques such as thermoelastic stress analysis (TSA) and digital image correlation (DIC). TSA requires a cyclic load to be applied to a structure for the measurement of the strain state; therefore, the test rig has been designed to be mounted on a standard servo-hydraulic test machine. As both TSA and DIC require an uninterrupted view of the surface of the test panel, an important consideration in the design is facilitating the optical access for the two techniques. To aid the test rig design a finite element (FE) model was produced. The model provides ...
The decrease mechanic effect on loads being transported, shock load limiters (dampers) are being widely used today. Usually, the materials having 'stress-strain' diagrams (#sigma#-#epsilon#) of compression with a substantial portion, where #sigma# = const., are used as dampers. Most widely used are dampers made of foam polystyrene having just the same compression diagram. Similar strain diagrams can be enlisted for some porous materials, timber under cross compression, perforated metallic crushers and some others. By selecting damper material, the level of transmitted to the protected object pressures can be varied from several to hundreds MPa. Timber, as being widely used and featuring good technologic properties together with low cost, becomes an attractive material to be used as the limiter of shock loads. This paper presents the results of stress-strain sequoia properties (USA deliverable) and birch properties ...
Hydrogen (H{sub 2}) emissions characteristics of H{sub 2}-diesel dual fuel engine were measured using a 2004 turbocharged heavy-duty diesel engine with H{sub 2} supplemented into the intake air. The emissions of H{sub 2} were measured using an Electron Pulse Ionization (EPI) Mass Spectrometer (MS). The effect of the amount of H{sub 2} added, the engine load, and diesel fuel flow rates on the emissions of H{sub 2} and its combustion efficiency in the engine were investigated. The addition of H{sub 2} under high load operation was notable for its ability to obtain high H{sub 2} combustion efficiency and improve brake thermal efficiency. However, the addition of H{sub 2} at low load resulted in high emissions of H{sub 2} due to the failure to initiate and support a sufficiently vigorous flame for the complete combustion of H{sub 2} present outside the diesel spray plume. The maximum H{sub 2} emissions of 1.4% (volume in dry ...
The aim of the present study was to describe the distribution and remobilization of plutonium (Pu) in the sediments off the Rhone river mouth. Most of the {sup 238}Pu and {sup 239,240}Pu isotopes introduced into the Rhone River were discharged by the liquid effluents released from the Marcoule reprocessing plant, located 120 km upstream the river mouth. Due to its high affinity for particles and its long half life, {sup 238}Pu is a promising tracer to follow the dispersion of particulate matter from the Rhone River to the Mediterranean Sea. During the 3 REMORA cruises, sediment samples were specifically collected in the Rhone pro-delta area and more offshore on the whole continental shelf of the Gulf of Lions. The measurements of alpha emitters gave a first detailed spatial distribution of Pu isotope concentrations in surface sediments off the Rhone mouth. Using {sup 137}Cs concentrations and their correlations with Pu isotopes, we were able to give a first ...
Dust detection and control in real time, represent one of the most challenging problem in all those environments where fine and ultrafine airborne particulate solids products are present. The presence of such products can be linked to several factors, often directly related and influenced by the working-production actions performed. Independently from the causes generating dust, airborne contaminants are an occupational problem of increasing interest as they are related to a wide number of diseases. In particular, airborne dusts are well known to be associated with several classical occupational lung diseases, such as the pneumoconiosis, especially at high levels of exposure. Nowadays there is also an increasing interest in other dust related diseases, from the most serious as cancer and asthma, to those related with allergies or irritation and other illnesses, also occurring at lower levels of exposure. Among the different critical factors influencing health risk ...
Percutaneous osseointegrated prostheses are being investigated as an alternative strategy to attach prosthetic limbs to patients. Although the use of these implants has shown to be promising in clinical trials, the ability to maintain a skin seal around an osseointegrated implant interface is a major challenge to prevent superficial and deep periprosthetic infections. The specific aim of this study was to establish a translational load-bearing ovine model to assess postoperative limb compensation and gait symmetry following a percutaneous osseointegrated implant. We tested the following hypotheses: (1) the animals would return to pre-amputation limb loads within 12-months; (2) the animals would return to a symmetrical gait pattern (stride length and time in stance) within 12-months. The results demonstrated that one month following surgery, the sheep loaded their amputated limb to a mean value of nearly 80% of their ...
One of the limiting contributors to the heat load constraint for the Yucca Mountain repository is the decay of Americium 241. A possible option to reduce the heat load produced by Am-241 is to eliminate or transmute it in a light water reactor thermal neutron environment, particularly, by taking advantage of the thermal fission cross section of Am-242 and Am-242m. In this study we employ lattice loading optimization techniques to define the americium/uranium blending and pin arrangements via an adaptation of the code FORMOSA-L to include the incineration of preloaded americium as an objective function. The optimization routines were designed to maximize americium transmutation, while maintaining power peaking below a predefined constraint. The viability of these lattice designs has been analyzed by creating bundles with these Am-spiked lattices and by loading these bundles into realistic 3D BWR ...
Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This report describes the theoretical background of the VAWT Stochastic Aerodynamic Loads (VAWT-SAL) computer code, whose purpose is to numerically simulate these random loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Stream Tube (DMST) analysis is employed to model the rotor's aerodynamic response. The analysis includes the effects of Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. The mean ambient wind is assumed to have a shear profile which is described by either a power law or a logarithmic variation ...
A bottom-up approach is used here to combine carbon nanotubes synthesized by CVD and organically capped platinum nanoparticles electrocatalyst exhibiting a direct electrochemical activity towards oxygen reduction. Both nano-objects are handled in liquid suspension and are associated together in a controlled way. The nanocomposite liquid dispersions can be precisely controlled in terms of platinum nanoparticles to carbon nanotubes weight ratios (NP/NT) which correspond to different coverages of nanotubes by nanoparticles. Electrodes with low to ultra-low platinum loadings can then be prepared on porous fuel cell carbon supports by filtration. The direct electrochemical activity towards aqueous oxygen reduction reaction (ORR) of electrodes with platinum loadings ranging from about 1 to 60 {mu}g/cm{sup 2} is reported without any activation step in order to keep the features of the nanoparticles intact. Before that, we studied the responses ...
The objective of this project is to develop a pellet formulation which is capable of achieving low sulfur partial pressures and a high capacity for sulfur, loaded from a hot fuel gas and which is readily regenerable. Furthermore the pellet must be strong for potential use in a fluidized bed and regenerable over many cycles of loading and regeneration. Regeneration should be in air or oxygen-depleted air to produce a high-concentration sulfur dioxide. Fixed-bed tests were conducted with several formulations of manganese sesquioxide and titania, and alumina They were subject to a simplified fuel gas of the oxygen-blown Shell type spiked with a 30,000ppmv concentration of H{sub 2}S. Pellet crush strengths for 4 and 2mm diameter pellets was typically 12 lbs per pellet and 4 lbs per pellet, respectively. For the most favorable of the formulations tested and under the criteria of break-through at less than 100ppmv H2S and loading ...
In the first part of this paper, IrO_2 electrodes produced by thermal decomposition of H_2IrCl_6 precursor were manufactured using the spin coating deposition technique, where centrifugal forces spread the precursor solution with simultaneous evaporation of the solvent on the rotating Ti substrate. It was found using this technique, that it is possible to obtain thin and uniform IrO_2 coatings with controlled loadings. The influence of the concentration of iridium salt in the precursor solution (c_0) as well as the influence of the rotation speed at which the substrate spins (#omega#) on the IrO_2 loading have been studied using voltammetric charge measurements. From these results, a simple relation has been proposed for the estimation of the IrO_2 loading for a given c_0 and #omega#. In the second part of this paper and from measurements performed using different IrO_2 loadings and formic acid ...
Three different configurations of cylindrical submerged media anaerobic reactors (SMARs) with packing volumes of 85 items were operated at 35 C for 415 days with COD loading rates varying from 1 to 12 g/l/d and three retention times of 0.5, 1, and 2 days. A synthetic waste consisting of a milk solution with a mineral supplement was used for the feed. Tracer studies on clean-bed and dirty-bed SMARs indicate that reactor configuration, biogas mixing, and biomass accumulation all have a significant effect on SMAR hydraulics and cause short-circuiting. Based on the isothermal energy dissipation theory, the higher hydrostatic pressures resulting from higher SMAR heights increases self-induced biogas mixing and improves the contact efficiency between substrate and organisms. Based on TCOD removal rate, the tallest SMAR performed slightly better at COD loading rates above 4/g/l/d. At COD loading rates equal to or below 4 g/l/d, ...
The objective of the research was to develop a machine combination for harvesting of small wood, which carries out both the harvesting and forest haulage. The development was started in September 1995. The first prototype of the machine is ready. A Lokomo 910 forest tractor was acquired for the tests. The prototype has been mounted on the tractor, and the tests have been started in the beginning of March 1996. The reconstruction of the device will be made after the tests, as well as the description of different working praxis. Time consumption study and the analysis of it will be made after the equipment tests. The device consists of a grapple equipped with a guillotine cutting device mounted on the tractor. The actual felling is made stem by stem in the test phase. The stem can be forwarded directly into the load or it can be left aside, and new stems can be brought beside it and then all the stems can be taken together into load. The ...
Extracellular matrix (ECM) comprises a rich meshwork of proteins and proteoglycans, which not only contains biological cues for cell behavior, but is also a reservoir for binding growth factors and controlling their release. Here we aimed to create a suitable bony microenvironment with cell-derived ECM and biodegradable ?-tricalcium phosphate (?-TCP). More specifically, we investigated whether the ECM produced by bone marrow-derived mesenchymal stem cells (hBMSC) on a ?-TCP scaffold can bind bone morphogenetic protein-2 (BMP-2) and control its release in a sustained manner, and further examined the effect of ECM and the BMP-2 released from ECM on cell behaviors. The ECM was obtained through culturing the hBMSC on a ?-TCP porous scaffold and performing decellularization and sterilization. SEM, XPS, FTIR, and immunofluorescent staining results indicated the presence of ECM on the ?-TCP and the amount of ECM increased with the incubation time. BMP-2 was loaded onto ...
Depth sensing indentation tests were carried out to obtain load-penetration depth curves of SiAlON-ZrO_2 ceramics under different peak loads ranging from 200 to 1800 mN. The values of indentation hardness (H_O_P, H_C_C) and reduced elastic modulus (E_O_P, E_C_C) were calculated by using Oliver-Pharr (OP) and Cheng-Cheng (CC) methods. The experimental results revealed that the indentation hardness and reduced elastic modulus exhibit peak-load dependence, i.e. indentation size effect. Both indentation hardness and reduced elastic modulus values were obtained by considering indenter tip roundness and machine compliance. These values obtained from the OP method are higher than from the CC method. On the other hand, h_f/h_m ratios were used to clarify the indentation deformation behaviour of the SiAlON-ZrO_2 ceramic. The experimental h_f/h_m values were lower than the reported critical value (0.7) for all applied test ...
Vehicle heating requires a substantial amount of energy. Engines in conventional cars produce enough waste heat to provide comfort heating and defogging/defrosting, even under very extreme conditions. Electric vehicles (EVs), however, generate little waste heat. Using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. Water vapor generated by the vehicle passengers is in large part responsible for the high heating loads existing in vehicles. In cold climates, the generation of water vapor inside the car may result in water condensation on the windows, diminishing visibility. Two strategies are commonly used to avoid condensation on windows: windows are kept warm, and a large amount of ambient air is introduced in the vehicle. Either strategy results in a substantial heating load. These strategies ...
This report presents the results of a survey of the uses of the refrigeration available from vaporizing liquefied natural gas. The major emphasis of the study is on peakshaving plants, which liquefy and regasify domestic gas; the minor emphasis is on base-load terminals, which gasify imported LNG continuously. There are 54 full-scale LNG peakshaving plants in the US and several others under construction. The US has three operating base-load import terminals. One more is under construction and several more large terminals have been proposed. There are at least 12 foreign base-load import terminals in operation, and more are under construction or are proposed. The report presents a survey of operating conditions for about 15 large domestic peakshaving plants. It also presents published design data for the existing US import terminals, for the major proposed import terminals, and for the major overseas import terminals. The ...
This paper reports the results of an investigation into the vibration of functionally graded cylindrical shells with flowing fluid, embedded in an elastic medium, under mechanical and thermal loads. By considering rotary inertia, the first-order shear deformation theory (FSDT) and the fluid velocity potential, the dynamic equation of functionally graded cylindrical shells with flowing fluid is derived. Here, heat conduction equation along the thickness of the shell is applied to determine the temperature distribution and material properties are assumed to be graded distribution along the thickness direction according to a power-law in terms of the volume fractions of the constituents. The equations of eigenvalue problem are obtained by using a modal expansion method. In numerical examples, effects of material composition, thermal loading, static axial loading, flow velocity, medium stiffness and shell geometry parameters on ...
Optimal capacitor placement determines the size, type, and location of capacitors to be installed on a radial distribution feeder that will reduce peak power and energy losses while minimizing the costs of investment and installation of the capacitor banks. This paper describes a sensitivity-based optimal placement of capacitors that employs a new load characterization scheme using a voltage-current-angle-logger. The proposed method allows modeling of loads of different power factors for different portions of the distribution feeder. The optimal solution is obtained by testing various combinations of capacitor banks (based on the smallest bank size specified by the user) and candidate nodes along the distribution feeder, and calculating the resultant savings. In order to reduce solution time, the candidate nodes are ranked according to their sensitivity factors. The highest ranking nodes are considered first in the optimization process. At a ...
In order to design roof bolting systems safely and economically, it is essential to understand the flexural behaviour of the immediate roof. Based on the strata sequence, the strata in the immediate roof are divided into three types. The flexural behaviour of the three strata types are investigated in terms of the following effects: roof span, horizontal stress, thickness and Young's modulus of the lowest strata. The suspension reinforcement mechanism is analysed using beam-column theory. The equations for the maximum bending stress, deflection and transferred bolt load for the bolted strata are derived. In the analysis, the bolt load is assumed to be a point load and a horizontal stress is uniformly applied to each stratum. The friction reinforcement mechanism is also investigated. The major function of roof bolting in this case is to create frictional resistance by tensioning the roof bolts so that the individual ...
The Underground Hydroelectric Pumped Storage (UHPS) Program Plan describes in detail the planned activities and expected accomplishments in the conduct of UHPS technology development and validation envisioned in the 1976 to 1990 time frame. This document describes the program objectives, implementation strategy, and management methodology. The concept of underground hydroelectric pumped storage is fully directed to application in the electric utility industry. This technology involves using electrical energy generated by base-load plants during off-peak load periods to drive a high-head pump/turbine which pumps water from a lower reservoir to a substantially elevated (upper) reservoir corresponding to a head of 1000 m or so. The upper reservoir is at ground level and the lower reservoir is below ground. Then, during peak-load periods, water in the upper reservoir is allowed to flow to the lower reservoir which, in turn, ...
Partial combustion of biomass in the gasifier generates producer gas that can be used for heating purposes and as supplementary or sole fuel in internal combustion engines. In this study, the potential of coir-pith and wood chips as the feedstock for gasifier is analyzed. The performance of the gasifier-engine system is analyzed by running the engine for various producer gas-air flow ratios and at different load conditions. The system is experimentally optimized with respect to maximum diesel savings and lower emissions in the dual fuel mode operation while using coir-pith and wood chips separately. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. Specific energy consumption in the dual fuel mode of operation is found to be in the higher side at all load conditions. The brake thermal efficiency of the engine while using wood chips in ...
In order to establish the optimum fueling in a natural gas fueled dual fuel engine, tests were made for some operational parameters and their combination on the engine performances and the exhaust emissions. The results show that the gas oil quantity should be increased and gas oil injection timing should be advanced to suppress unburned hydrocarbon emission at middle and low output range, while the quantity should be reduced and the timing should be retarded to avoid onset of knock at high loads. The unburned hydrocarbon emission and the thermal efficiency are improved at the same load avoiding too lean natural gas premixture by restriction of intake charge air. However the improvement is limited because the ignition and initial combustion of pilot diesel fuel is deteriorated when the cylinder pressure is excessively lowered by throttling. The increase in pilot gas oil amount is effective for low-load operation and the ...
Influence of gamma irradiation and storage on the microbial load, chemical and sensory quality of chicken kabab was investigated. Chicken kabab was treated with 0, 2, 4 or 6 kGy doses of gamma irradiation. Treated and untreated samples were kept in a refrigerator (1-4 deg. C). Microbiological, chemical and sensory characteristics of chicken kabab were evaluated at 0-5 months of storage. Gamma irradiation decreased the microbial load and increased the shelf-life of chicken kabab. Irradiation did not influence the major constituents of chicken kabab (moisture, protein and fats). No significant differences (p>0.05) were observed for total acidity between non-irradiated (control) and irradiated chicken kabab. Thiobarbitric acid (TBA) values (expressed as mg malonaldehyde (MDA)/kg chicken kabab) and volatile basic nitrogen (VBN) in chicken kabab were not affected by the irradiation. Sensory evaluation showed no significant differences between ...
This study evaluates the correlation between transplanted Asiatic clam and indigenous community responses to acid mine drainage and nutrient loading in first-to-third-order streams, by comparing the toxicological endpoints of clam survival and growth with benthic macro-invertebrate community indices as community responses to both acid mine drainage and nutrient loading. Clam survival was found to be positively correlated with water column pH and negatively correlated with conductivity and metal concentrations. There was also a positive correlation with the relative abundance of the macro-invertebrate Ephemeroptera, the most sensitive taxonomic group, to acid mine drainage in this watershed. No correlation was found between clam growth and acid mine drainage inputs, but there was evidence of positive correlation with nitrate concentrations and the relative abundance of collector-filterer functional feeding groups. These results suggest that clam ...
The theory of a method of determination of reactivity from power spectral density measurements with /sup 252/Cf and the results of experiments with a critical assembly mockup of a liquid-metal fast breeder reactor (LMFBR) and with uranium (93.2 wt % /sup 235/U) metal cylinders and a sphere are presented. This method of reactivity determination has an advantage over existing methods in that it determines the reactivity only from properties of the reactor at the subcritical state of interest and thus does not require a calibration near delayed criticality. In these experiments, the reactivity was varied by changing the fissile loading or the amount of neutron absorber inserted; for the LMFBR mockup, the reactivity varied to approximately 75 dollars subcritical, and for the uranium metal assemblies to approximately 30 dollars subcritical. These experiments verified for the first time the predictions of theory that could be tested in the measurements. This method has ...
The magnetically controlled plasma opening switch (MCPOS) is an advanced plasma opening switch that utilizes magnetic fields to improve operation. Magnetic fields always dominate terawatt, pulsed power plasma opening switches. For that reason, the MCPOS uses controlled applied magnetic fields with magnitude comparable to the self-magnetic field of the storage inductor. One applied field holds the plasma in place while energy accumulates in the storage inductor, then another applied field pushes the plasma away from the cathode to allow energy to flow downstream. Over a ten month period, an MCPOS was designed, built, and tested on DECADE Module 2 at Physics International. The peak drive current was 1.8 MA in 250 ns. The output parameters were up to 1 MA into an electron beam load. The radiation temporal pulse width averaged 60 nanoseconds full-width at half-maximum. The peak load voltage ranged from one to two megavolts. The experiments ...
This paper investigated the effect of hydrogen (H{sub 2}) addition on the combustion process of a heavy-duty diesel engine. The addition of a small amount of H{sub 2} was shown to have a mild effect on the cylinder pressure and combustion process. When operated at high load, the addition of a relatively large amount of H{sub 2} substantially increased the peak cylinder pressure and the peak heat release rate. Compared to the two-stage combustion process of diesel engines, a featured three-stage combustion process of the H{sub 2}-diesel dual fuel engine was observed. The extremely high peak heat release rate represented a combination of diesel diffusion combustion and the premixed combustion of H{sub 2} consumed by multiple turbulent flames, which substantially enhanced the combustion process of H{sub 2}-diesel dual fuel engine. However, the addition of a relatively large amount of H{sub 2} at low load did not change the two-stage heat release ...
The main purpose of this paper is to explore a numerical algorithm for determining the contact stress when a circular crowned roller is compressed between two plates. To start with, the deformation curve on a plate surface will be derived by using the contact mechanical model. Then, the contact stress distribution along the roller which occurs on the plate surface is divided into three parts: from the center of contact to the edge, the edge and apart from the contact line. The first part is calculated by the elastic contact theorem for the contact subjected to nominal stress between non-crowned parts of roller and plates, the second part is obtained by the classical Hertzian contact solution for the contact between crowned parts of roller and plates, and the third part is simulated as exponential decay. In order to overcome the defect of the half space theorem, in which a plate with infinite thickness is assumed initially, a weighting method is introduced to find the contact stress of ...