Academic literature on the topic 'Self-loading transporter'
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Journal articles on the topic "Self-loading transporter"
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Lee, Kyungwoo, Daejin Min, Yonghyun Choi, Semi Yoon, Jaehee Jang, Jangsun Hwang, Hojeong Jeon, Yong Woo Cho, and Jonghoon Choi. "Self-Assembling β-Glucan Nanomedicine for the Delivery of siRNA." Biomedicines 8, no. 11 (November 12, 2020): 497. http://dx.doi.org/10.3390/biomedicines8110497.
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We aimed to design and manufacture a transporter capable of delivering small interfering RNAs (siRNAs) into the skin without causing any damage. β-glucans are unique chiral polysaccharides with well-defined immunological properties and supramolecular wrapping ability. However, the chiral properties of these polymers have hardly been applied in drug delivery systems. In this study, β-glucan nanoparticles were designed and manufactured to deliver genetic material to the target cells. The β-glucan molecules were self-assembled with an siRNA into nanoparticles of 300–400 nm in diameter via a conformational transition process, in order to construct a gene delivery system. The assembled gene nanocarriers were associated with high gene-loading ability. The expression and efficiency of siRNA were verified after its delivery via β-glucan. Our results provide evidence that β-glucan nanoparticles can be effectively used to deliver siRNA into the cells.
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Franksson, L., E. George, S. Powis, G. Butcher, J. Howard, and K. Kärre. "Tumorigenicity conferred to lymphoma mutant by major histocompatibility complex-encoded transporter gene." Journal of Experimental Medicine 177, no. 1 (January 1, 1993): 201–5. http://dx.doi.org/10.1084/jem.177.1.201.
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Presentation of antigenic peptides by major histocompatibility complex (MHC) class I molecules requires MHC-encoded molecules of the adenosine triphosphate binding cassette (ABC) family. Defects in these proteins represent a potential risk, since they are essential links in the machinery of T cell-mediated surveillance which continuously scrutinizes peptide samples of cellular proteins. Nevertheless, transfection of the mouse lymphoma mutant RMA-S with the rat ABC gene mtp2a (homologue to mouse HAM2 and human RING11), commonly termed TAP-2 genes, led to a marked increase in tumor outgrowth potential in vivo. This occurred despite restored antigen presentation and sensitivity to cytotoxic T lymphocytes, and was found to be due to escape from natural killer (NK) cell-mediated rejection. It has previously been proposed that adequate expression of self-MHC class I is one important mechanism to avoid elimination by NK cells. Our data argue that a defect in the machinery responsible for processing and loading of peptides into MHC class I molecules is sufficient to render cells sensitive to elimination by NK cells. The latter thus appear to function as a surveillance of the peptide surveillance machinery.
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Moriwaki, S., B. S. Korn, Y. Ichikawa, L. van Kaer, and S. Tonegawa. "Amino acid substitutions in the floor of the putative antigen-binding site of H-2T22 affect recognition by a gamma delta T-cell receptor." Proceedings of the National Academy of Sciences 90, no. 23 (December 1, 1993): 11396–400. http://dx.doi.org/10.1073/pnas.90.23.11396.
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We have previously identified a self-reactive gamma delta T-cell clone (KN6) specific for the H-2T region gene product T22b. Now we have investigated by an in vitro mutagenesis analysis of the T22b gene the possibility that the interaction between the KN6 gamma delta T-cell receptor and T22b involves a peptide. The results demonstrate that mutations at the floor of the putative antigen-binding groove of T22b affect recognition by the gamma delta T-cell receptor. Furthermore, we have shown that KN6 cells react with cells that are deficient in the class I peptide transporter TAP1/TAP2. These results suggest that peptide is involved in the interaction of the KN6 T-cell receptor with T22 and that loading of T22 with the putative peptide is TAP1/TAP2-independent.
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He, Yu Jing, Ang Wu, and Yan Li. "The Virtual Design of the Self - Propelled Tomato Harvester." Key Engineering Materials 621 (August 2014): 407–12. http://dx.doi.org/10.4028/www.scientific.net/kem.621.407.
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In order to improve the efficiency of life, reduce the labor intensity, On the basis of agronomic requirements, design a new type of tomato harvesting machine.Virtual design is aimed at cutting device,transporter,fruitseedling separating device,internalconveyer, transverse conveyer, Ascension conveyer, color select set, telescopic boom. By cutting machine, through a series of excluding foreign body, direct transportation loading, finished the harvest.The machine harvesting, transportation, separation and color to choose, and other functions in one body, make the post-harvest processing tomato can achieve enterprise standards.
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Li, L. P., M. D. Buschmann, and A. Shirazi-Adl. "Strain-rate Dependent Stiffness of Articular Cartilage in Unconfined Compression." Journal of Biomechanical Engineering 125, no. 2 (April 1, 2003): 161–68. http://dx.doi.org/10.1115/1.1560142.
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The stiffness of articular cartilage is a nonlinear function of the strain amplitude and strain rate as well as the loading history, as a consequence of the flow of interstitial water and the stiffening of the collagen fibril network. This paper presents a full investigation of the interplay between the fluid kinetics and fibril stiffening of unconfined cartilage disks by analyzing over 200 cases with diverse material properties. The lower and upper elastic limits of the stress (under a given strain) are uniquely established by the instantaneous and equilibrium stiffness (obtained numerically for finite deformations and analytically for small deformations). These limits could be used to determine safe loading protocols in order that the stress in each solid constituent remains within its own elastic limit. For a given compressive strain applied at a low rate, the loading is close to the lower limit and is mostly borne directly by the solid constituents (with little contribution from the fluid). In contrast, however in case of faster compression, the extra loading is predominantly transported to the fibrillar matrix via rising fluid pressure with little increase of stress in the nonfibrillar matrix. The fibrillar matrix absorbs the loading increment by self-stiffening: the quicker the loading the faster the fibril stiffening until the upper elastic loading limit is reached. This self-protective mechanism prevents cartilage from damage since the fibrils are strong in tension. The present work demonstrates the ability of the fibril reinforced poroelastic models to describe the strain rate dependent behavior of articular cartilage in unconfined compression using a mechanism of fibril stiffening mainly induced by the fluid flow.
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Skrypnyk, О., V. Abrakitov, and A. Stepanenko. "RISK- ANALYSIS OF DIAGNOSTIC DIAGNOSIS DURING OPERATION OF SELF-PROPELLED LOADING CRANES OF THE ARROW TYPE." Municipal economy of cities 1, no. 154 (April 3, 2020): 267–71. http://dx.doi.org/10.33042/2522-1809-2020-1-154-267-271.
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The problem of managing the safe operation of hoisting machines with an expired service life is associated with solving extremely complex interrelated tasks through a set of organizational and technical measures aimed at establishing the actual risk and economic feasibility of further operation. The most important condition in this case is the conduct of an expert examination of industrial safety and technical diagnostics, the results of which make it possible to establish the real state of hoisting machines at the current time. The safety of hoisting machines, including after the expiration of the standard service life (assigned resource), is associated with design features, workmanship, installation quality, their operation modes and a number of other factors. However, for heavily loaded hoisting machines, the main technical obstacle to safe operation is metal fatigue The results of a statistical analysis of defects detected by expert diagnosis of self-propelled boom-type cranes that have fulfilled the standard operating period are presented. The largest number of defects is associated with the destruction and wear of structural elements, the occurrence of fatigue cracks and the violation of the operating conditions of the equipment. The greatest number of defects is found in the hydraulic system of cranes, elements of the cable-block system, less often in metal construction. To conduct a risk analysis of self-propelled jib cranes in conditions of insufficient information, a methodology for expert assessments is proposed. It allows you to evaluate the impact of potential defects of self-propelled jib cranes on the amount of economic damage to the crane itself and the transported load and on the magnitude of the traumatic impact on humans. Defects and damage to the metal structures of the cranes discovered during the examinations are the result of the following combination of reasons: low quality of the metal (mild steel); unsatisfactory design; unsatisfactory quality of manufacture and installation of individual elements; environmental aggressiveness; operation of cranes in an unintended mode, poor maintenance and repair Keywords: safety, propelled jib crane, defect, expert assessment, risk analysis, diagnosis.
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Zubkov, Valeriy V., and Nina F. Sirina. "Improvement of freight transportation technologiy in the multimodal railway-water transport." Vestnik of the Railway Research Institute 78, no. 5 (December 23, 2019): 284–89. http://dx.doi.org/10.21780/2223-9731-2019-78-5-289.
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Analysis of arrangement of the local operation during freight transportation by the multimodal railway-water transport to Tobolsk river port of the Ob-Irtysh bassin is presented. Dynamics of growth of construction cargo loading and increase of the volumes of their transportation to the port enhance the working capacity of Sverdlovsk railroad, which increases the loading level of its processing and carrying capacities. It should be noted that the level of quality and reliability of such transportation is reduced in the period of the transport infrastructure repair, when the number of the freight trains temporarily removed from operation is grown at the approaches to the port railway station. The search for the possible solutions of arranging the local operation was conducted at the route limited in the carrying and processing capabilities, in particular at the interaction of two types of transport: railway and inland water transport. Effective solutions for automation of the processes of adaptive approval of the volume of transported cargo are proposed, as well as the methods and options of their transportation at all stages of transportation services, forecasting and planning of the regional freight transportation as a part of the inter-industry transportation. The “Electronic service of the complex transportation services” system is presented, which provides for selection of the best option of effect on the main quality criteria of the regional freight transportation and ensures self-arrangement and self-support of the process when its conditions are changed under the impact of external and internal factors. The system calculates the economically feasible mode of transportation, performs adaptive approval of the volumes of transported cargo at all stages of the technological cycle of rendering complex transportation services. The system provides for information and analytical support of the functions of planning, arrangement of local operation, and collection, analysis, and processing of statistical data. Methods of the system construction are used for control of the transportation services when arranging the car traffic volume of inert cargo making the forecast of their delivery. The “Electronic service of the complex transportation services” system has passed the state registration.
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Ren, Tongqun, Xin Li, Xiaodong Wang, Zheng Xu, Yugang Liu, Jin Yang, and Jiang Guo. "Automatic Sorting System for Rigid Piezoelectric Transducer Wafers Used in Displacement Adjustment." Micromachines 11, no. 10 (September 30, 2020): 915. http://dx.doi.org/10.3390/mi11100915.
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Piezoelectric transducer wafers are usually used in pairs to adjust the resonant cavity length of the ring laser gyro. In practice, the paired wafers are required to have similar piezoelectric charge coefficient d31. To handle the pairing operation in-batch, an automatic sorting system was developed on the basis of deformation measurement, which adopted a frame of a Cartesian-coordinate robot. The wafers were self-aligned in the vertical direction, and a vacuum holder was used to pick up, transfer, and then place them on thee testing desk one by one. The excitation voltage was loaded on the wafer by a specifically designed electrode, and the resulting micro deformation was measured by dual opposite inductive micrometers using the relative measurement principle. This particular electrode has the function of attitude self-adjustment and vacuum adsorption, which is conducive to loading the voltage reliably and protecting the wafer from undesired damage. Finally, the wafers were transported to different stock bins based on the measuring results. This system is suited to handle a mass of wafers by continuous processing on site for its high reliability and measurement consistency. The measurement accuracy, validated by laser interferometry, was better than 0.5 μm and the repeatability was superior to 0.1 μm.
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Laskaris, Zoey, Chad Milando, Stuart Batterman, Bhramar Mukherjee, Niladri Basu, Marie S. O’neill, Thomas G. Robins, and Julius N. Fobil. "Derivation of Time-Activity Data Using Wearable Cameras and Measures of Personal Inhalation Exposure among Workers at an Informal Electronic-Waste Recovery Site in Ghana." Annals of Work Exposures and Health 63, no. 8 (July 23, 2019): 829–41. http://dx.doi.org/10.1093/annweh/wxz056.
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Abstract Objectives Approximately 2 billion workers globally are employed in informal settings, which are characterized by substantial risk from hazardous exposures and varying job tasks and schedules. Existing methods for identifying occupational hazards must be adapted for unregulated and challenging work environments. We designed and applied a method for objectively deriving time-activity patterns from wearable camera data and matched images with continuous measurements of personal inhalation exposure to size-specific particulate matter (PM) among workers at an informal electronic-waste (e-waste) recovery site. Methods One hundred and forty-two workers at the Agbogbloshie e-waste site in Accra, Ghana, wore sampling backpacks equipped with wearable cameras and real-time particle monitors during a total of 171 shifts. Self-reported recall of time-activity (30-min resolution) was collected during the end of shift interviews. Images (N = 35,588) and simultaneously measured PM2.5 were collected each minute and processed to identify activities established through worker interviews, observation, and existing literature. Descriptive statistics were generated for activity types, frequencies, and associated PM2.5 exposures. A kappa statistic measured agreement between self-reported and image-based time-activity data. Results Based on image-based time-activity patterns, workers primarily dismantled, sorted/loaded, burned, and transported e-waste materials for metal recovery with high variability in activity duration. Image-based and self-reported time-activity data had poor agreement (kappa = 0.17). Most measured exposures (90%) exceeded the World Health Organization (WHO) 24-h ambient PM2.5 target of 25 µg m−3. The average on-site PM2.5 was 81 µg m−3 (SD: 94). PM2.5 levels were highest during burning, sorting/loading and dismantling (203, 89, 83 µg m−3, respectively). PM2.5 exposure during long periods of non-work-related activities also exceeded the WHO standard in 88% of measured data. Conclusions In complex, informal work environments, wearable cameras can improve occupational exposure assessments and, in conjunction with monitoring equipment, identify activities associated with high exposures to workplace hazards by providing high-resolution time-activity data.
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Arias, Elsa R., Vivian Angarita-Villamizar, Yolima Baena, Claudia Parra-Giraldo, and Leon D. Perez. "Phospholipid-Conjugated PEG-b-PCL Copolymers as Precursors of Micellar Vehicles for Amphotericin B." Polymers 13, no. 11 (May 27, 2021): 1747. http://dx.doi.org/10.3390/polym13111747.
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Amphotericin B (AmB) is a widely used antifungal that presents a broad action spectrum and few reports on the development of resistance. However, AmB is highly toxic, causing renal failure in a considerable number of treated patients. Although when AmB is transported via polymer micelles (PMs) as delivery vehicles its nephrotoxicity has been successfully attenuated, this type of nanoparticle has limitations, such as low encapsulation capacity and poor stability in aqueous media. In this research, the effect of modifying polyethyleglicol-block-poly(ε-caprolactone) (PEG-b-PCL) with 1,2-distearoyl-sn-glycero-3-phosphorylethanolamine (DSPE) on the performance of PMs as vehicles for AmB was studied. PEG-b-PCL with two different lengths of a PCL segment was prepared via ring opening polymerisation and modified with DSPE at a post-synthesis stage through amidation. Upon modification with DSPE, a copolymer was self-assembled, thereby producing particles with hydrodynamic diameters below 100 nm and a lower critical micelle concentration than that of the raw copolymers. Likewise, in the presence of DSPE, the loading capacity of AmB increased because of the formed intermolecular interactions, such as hydrogen bonds, which also caused a lower aggregation of this drug. The assessment of in vitro toxicity against red blood cells indicated that the toxicity of AmB decreased upon encapsulation; however, its antifungal action against clinical yeasts was maintained and enhanced, as indicated by a decrease in its minimum inhibitory concentration.
Dissertations / Theses on the topic "Self-loading transporter"
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Dvořák, Lukáš. "Modifikace konstrukce samonakládacího transportéru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443193.
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This master’s thesis deals with research similar self-loading packege transporters. The stress analysis and modification of the selected transporter are followed. The master thesis contains stress analysis of the original version, design of a modified version and stress analysis of the modified version. Then the original and modified versions are compared.
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Jakobtorweihen, Sven, Christopher P. Lowe, Frerich J. Keil, and Berend Smit. "Understanding the loading dependence of self-diffusion in carbon nanotubes: Understanding the loading dependence of self-diffusion in carbonnanotubes." Diffusion fundamentals 2 (2005) 20, S. 1, 2005. https://ul.qucosa.de/id/qucosa%3A14349.
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The influence of loading on the self-diffusion in an isolated single walled carbon nanotube is studied by molecular dynamics simulations. By simulating the carbon nanotube as a flexible framework we demonstrate that the flexibility has a crucial influence on self-diffusion at low loadings [1]. While simulating the nanotube as rigid a remarkable increase of the diffusion coefficient at low loadings is observed [2]. Molecular dynamics simulations of a fully flexible nanotube result in a far less pronounced increase, by a further reduction of the loading the diffusion becomes constant again.
To incorporate the influence of the flexible walls in a simulation of a rigid nanotube, we have introduced a Lowe-Andersen thermostat which works on interface-fluid collisions [1]. The reproduction of the results of a flexible carbon nanotube by a rigid nanotube simulation is excellent. With this approach we simulate the loading dependent self-diffusion in carbon nanotubes. The influence of pore width and temperature on
self-diffusion is studied. Furthermore, the influence of adsorption strength is investigated by comparing the self-diffusivities of different components. For small pores, in which the molecules cannot pass each other, single-file diffusion is observed under certain conditions.
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Jakobtorweihen, Sven, Christopher P. Lowe, Frerich J. Keil, and Berend Smit. "Understanding the loading dependence of self-diffusion in carbon nanotubes." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-195333.
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The influence of loading on the self-diffusion in an isolated single walled carbon nanotube is studied by molecular dynamics simulations. By simulating the carbon nanotube as a flexible framework we demonstrate that the flexibility has a crucial influence on self-diffusion at low loadings [1]. While simulating the nanotube as rigid a remarkable increase of the diffusion coefficient at low loadings is observed [2]. Molecular dynamics simulations of a fully flexible nanotube result in a far less pronounced increase, by a further reduction of the loading the diffusion becomes constant again.
To incorporate the influence of the flexible walls in a simulation of a rigid nanotube, we have introduced a Lowe-Andersen thermostat which works on interface-fluid collisions [1]. The reproduction of the results of a flexible carbon nanotube by a rigid nanotube simulation is excellent. With this approach we simulate the loading dependent self-diffusion in carbon nanotubes. The influence of pore width and temperature on
self-diffusion is studied. Furthermore, the influence of adsorption strength is investigated by comparing the self-diffusivities of different components. For small pores, in which the molecules cannot pass each other, single-file diffusion is observed under certain conditions.
Conference papers on the topic "Self-loading transporter"
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Huang, Hen-Wei, Andrew J. Petruska, Mahmut Selman Sakar, Maria Skoura, Franziska Ullrich, Qi Zhangm, Salvador Pane, and Bradley J. Nelson. "Self-folding hydrogel bilayer for enhanced drug loading, encapsulation, and transport." In 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2016. http://dx.doi.org/10.1109/embc.2016.7591143.
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Nesmiyanov, I. A., M. E. Nikolaev, and N. S. Vorobyova. "ROBOTIC LOADING AND TRANSPORT UNIT FOR PICKING UP VEGETABLE NETS FROM THE FIELD." In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS Volume 2. DSTU-Print, 2020. http://dx.doi.org/10.23947/interagro.2020.2.699-703.
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For the mechanization of loading and transport work when harvesting vegetables packed in nets, the design of the loading manipulator on the mobile chassis is proposed. The required number of degrees of freedom of capture for the quality assurance of the process is substantiated. In order to use the loading manipulator as an autonomous robot, the features of controlling the capture of the proposed manipulator on a mobile self-propelled chassis are defined.
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Li, Jia, Songlin Liu, Xuebing Ma, Yong Pu, and Xiangcun Chen. "Preliminary Neutronics Design and Analysis of the Bit Helium Cooling Ceramics Blanket for CFETR." In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15696.
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CFETR is a Tokamak fusion engineering test reactor whose concept design is being developed in China. It is a key issue for breeding blanket design to attain tritium self-sufficiency as one of important missions of CFETR. This paper presents a preliminary neutronics design and analysis employing a BIT (breeder inside tube) type helium cooling ceramics blanket (HCCB) design concept as one of CFETR blanket design candidates. Firstly, 1D reactor model was designed using ceramic breeder Li4SiO4 and beryllium in pebble for multiplier. The primary blanket parameters were optimized to yield the higher tritium breeder ratio (TBR), including the thickness of outboard breeder blanket, enrichment of Li-6 and ratio of Li4SiO4 to Be. Secondly, based on the optimized blanket parameters and plasma parameters, a detailed 3D neutronics calculation model of 22.5° reactor sector was developed, including blanket modules, shield, divertor, vacuum vessel and TF coil. The gap between blanket modules had been taken into account. Finally, a set of nuclear analyses were carried out addressing the key neutronics issues by Monte Carlo neutron-photon transport code MCNP version 5 and the FENDL-2.1 data library. The preliminary analysis results showed that the global TBR could achieve 1.21 which satisfied the tritium self-sufficiency demand. Nuclear heat, neutronic flux, and distribution of neutron wall loading (NWL) were also analyzed as source terms of the blanket thermal-hydraulics design and reactor nuclear response.
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Zhou, Jia, Paul Carman, Hong Sun, Richard Wheeler, Harold Brannon, D. V. Satya Gupta, and Ray Starks. "Revolutionary Particle Fluid System Unlocks of Fractured Reservoir Potential." In SPE Hydraulic Fracturing Technology Conference. SPE, 2015. http://dx.doi.org/10.2118/spe-173369-ms.
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Abstract Post-treatment production analyses for hydraulic fracturing treatments with conventional crosslinked gel or slickwater often indicate that the treatments do not achieve the designed stimulation effectiveness, which could be attributed to non-optimal proppant placement and/or significantly damaged fracture conductivity. Although conventional crosslinked fluids are observed to provide good proppant suspension in laboratory environments, they might not provide the desired proppant transport under downhole conditions. Crosslinked fluids are known to be difficult to clean up, and thus are notorious for imparting gel damage to proppant pack and formation. Slickwater can be used to mitigate gel damage by reducing the effective polymer loadings, but consequential extreme proppant settling and banking problems reduce the chance of achieving fracture performance. Several proppant placement techniques have been developed to generate highly conductive paths for hydrocarbons to flow from an unconventional reservoir to the wellbore, such as hybrid fracturing, reverse hybrid fracturing, and channel fracturing, each of which predominantly rely upon high viscosity fluids to carry the proppant to the designated location. This paper presents a non-traditional fracturing fluid system and application technique with near perfect proppant suspension and transport, high fracture conductivity, and self-diverting characteristics. The revolutionary fracturing fluid system employs engineered packing of particle domains for proppant suspension mechanics that are significantly different from crosslinked polymer systems which use polymer chain overlap and inter-chain crosslinking to generate viscosity governed proppant transport. The unique gel particle structure perfectly suspends proppant for several hours at reservoir conditions to facilitate better transverse and vertical placement of proppant in the fracture and significantly increases the fractured surface area, which is one of most important factors in unconventional reservoir production. The self-diverting tendencies offer the potential to maximize created fracture area while simultaneously reducing the treating fluid volumes without the addition of costly diverting additives. The degradability of the fluid can be controlled at reservoir conditions by fluid pH and/or breaker loading to yield near 100% regained proppant pack conductivity. This paper discusses the evolution of the technology, and laboratory results for this unique fluid system. The system can unlock reservoir potential in areas requiring high fractured surface area and high regained conductivity, such as unconventional liquid-rich formations.
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Liu, Wing Kam, and Ashfaq Adnan. "Multiscale Modeling and Simulation for Nanodiamond-Based Therapeutic Delivery." In ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13273.
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It has been demonstrated from recent research that nanodiamond(ND)-enabled drug delivery as cancer therapeutics represents an important component of optimized device functionality. The goal of the current research is to develop a multiscale modeling technique to understand the fundamental mechanism of a ND-based cancer therapeutic drug delivery system. The major components of the proposed device include nanodiamonds (ND), parylene buffer layer and doxorubicin (DOX) drugs, where DOX loaded self-assembled nanodiamonds are packed inside parylene capsule. The efficient functioning of the device is characterized by its ability to precisely detect targets (cancer cells) and then to release drugs at a controlled manner. The fundamental science issues concerning the development of the ND-based device includes (a) a precise identification of the equilibrium structure, surface electrostatics and self assembled morphology of nanodiamonds, (b) understanding of the drug/biomarker adsorption and desorption process to and from NDs, (c) rate of drug release through the parylene buffers, and finally, (d) device performance under physiological condition. In this study, we aim to systematically address these issues using a multscale computational framework. Specifically, the structure and electrostatics of the functionalized NDs are predicted by quantum scale calculation (Density Functional Tight Binding). The DFTB) study on smaller NDs suggests a facet dependent charge distributions on ND surfaces. Using the charges for smaller NDs (∼ valid for 1–3.3 nm dia ND), we then determined surface charges for larger (4–10 nm) truncated octahedral nanodiamonds (TOND). We found that the [100] face and the [111] face contain positively and negatively charged atoms, respectively. Employing this surface electrostatics of nanodiamonds, atomistic-scale simulations are performed to simulate the self-assembly process of the NDs and drug molecules in a solution as well as to evaluate nanoscale diffusion coefficient of DOX molecules. In order to quantify the nature of the aggregate morphology, a fractal analysis has been performed. The mass fractal dimensions for a variety of aggregate size have been obtained from molecular simulations assuming ‘diffusion-limited aggregation (DLA)’ process. Then, by considering the experimentally observed aggregate dimensions, by using DLA based fractal analysis and by utilizing Lagvankar-Gemmell Model for aggregate density, a continuum model for larger aggregates will be developed to characterize aggregate strengths and break-up mechanism, which in turn will help us to understand how aggregate size can be reduced. In this talk, an outline for this continuum model will be discussed. In addition, we have been performing molecular simulations on DOX-ND where multiple drug molecules are allowed to interact with a cluster of self-assembled nanodiamonds in pH controlled solution. The purpose of this study is to find the effect of solution pH on the loading and release of drug to and from nanodiamonds. Our initial results show that a higher pH is necessary to ensure drug release from nanodiamonds. Once we completely understand the essential physics of pH controlled drug loading and release, we plan to develop multiscale models of tumor nodules to represent them as a collection of individual tumor cells. Each cell will be then modeled as a deformable body comprised of three homogenous materials: cortex membrane, cytosol and nucleus. The cortex membrane and the cytosol will serve as a weak permeable medium where the absorption coefficients of the doxorubicin remain constant and obey Fick’s law. In this study, it will be assumed that drug release from the microdevice to its outer periphery will be governed by Fickian Diffusion. It will also be assumed that the complex flow of drug through the interstitial fluid of the body will be dictated by Darcy’s law. It will be assumed that the solute drug transport in these regions will be due to a combination of convection, diffusion, elimination in the intra- and extra-cellular space, receptive cell internalization and degradation. Results from this study will provide fundamental insight on the definitive targeting of infected cells and high resolution controlling of drug molecules.
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Doucet, M., L. Durand Terrasson, and J. Mouton. "Safety Criticality Standards Using the French CRISTAL Code Package: Application to the AREVA NP UO2 Fuel Fabrication Plant." In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89017.
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Criticality safety evaluations implement requirements to proof of sufficient sub critical margins outside of the reactor environment for example in fuel fabrication plants. Basic criticality data (i.e., criticality standards) are used in the determination of sub critical margins for all processes involving plutonium or enriched uranium. There are several criticality international standards, e.g., ARH-600, which is one the US nuclear industry relies on. The French Nuclear Safety Authority (DGSNR and its advising body IRSN) has requested AREVA NP to review the criticality standards used for the evaluation of its Low Enriched Uranium fuel fabrication plants with CRISTAL V0, the recently updated French criticality evaluation package. Criticality safety is a concern for every phase of the fabrication process including UF6 cylinder storage, UF6-UO2 conversion, powder storage, pelletizing, rod loading, assembly fabrication, and assembly transportation. Until 2003, the accepted criticality standards were based on the French CEA work performed in the late seventies with the APOLLO1 cell/assembly computer code. APOLLO1 is a spectral code, used for evaluating the basic characteristics of fuel assemblies for reactor physics applications, which has been enhanced to perform criticality safety calculations. Throughout the years, CRISTAL, starting with APOLLO1 and MORET 3 (a 3D Monte Carlo code), has been improved to account for the growth of its qualification database and for increasing user requirements. Today, CRISTAL V0 is an up-to-date computational tool incorporating a modern basic microscopic cross section set based on JEF2.2 and the comprehensive APOLLO2 and MORET 4 codes. APOLLO2 is well suited for criticality standards calculations as it includes a sophisticated self shielding approach, a Pij flux determination, and a 1D transport (Sn) process. CRISTAL V0 is the result of more than five years of development work focusing on theoretical approaches and the implementation of user-friendly graphical interfaces. Due to its comprehensive physical simulation and thanks to its broad qualification database with more than a thousand benchmark/calculation comparisons, CRISTAL V0 provides outstanding and reliable accuracy for criticality evaluations for configurations covering the entire fuel cycle (i.e. from enrichment, pellet/assembly fabrication, transportation, to fuel reprocessing). After a brief description of the calculation scheme and the physics algorithms used in this code package, results for the various fissile media encountered in a UO2 fuel fabrication plant will be detailed and discussed.
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Kremensas, Arūnas, Agnė Kairytė Kairytė, Saulius Vaitkus, Sigitas Vėjelis, Giedrius Balčiūnas, Anna Strąkowska, and Sylwia Członka. "Mechanical performance of biodegradable hemp shivs and corn starch-based biocomposite boards." In The 13th international scientific conference “Modern Building Materials, Structures and Techniques”. Vilnius Gediminas Technical University, 2019. http://dx.doi.org/10.3846/mbmst.2019.132.
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For the production of traditional building materials, excavated natural resources are used. The production process of such materials requires high-energy demands, wherefore, high amounts of CO2 gases, which have a great impact on climate change, are emitted. Only a small part of such materials is effectively recycled and reused. Generally, they are transported to landfills, which rapidly expand and may pollute the soil, groundwater and air. Currently, a great attention is paid to the production of novel building materials. The aim is to use as less excavated materials as possible and replace them by natural renewable resources. Therefore, the recycling and utilisation at the end of life cycle of such materials would be easier and generation of waste would reduce. This way, the efforts of switching to circular economy are being put. One of the approaches – wider application of vegetable-based raw materials (cultivated and uncultivated agricultural plants). The usage of fibre hemp shives (HS) as an aggregate and corn stach (CS) as a binding material allows development of biocomposite boards (WPCs) which could contribute to the solution of the before mentioned problems. Bio-sourced materials combined with a polymer matrix offer an interesting alternative to traditional building materials. To contribute to their wider acceptance and application, an investigation into the use of wood-polymer composite boards is presented. In this study, biocomposite boards for the building industry are reported. WPCa are fabricated using a dry incorporation method of corn starch and HS treatment with water at 100 °C. The amount of CS and the size of the HS fraction are evaluated by means of compressive, bending and tensile strength, as well as microstructure. The results show that the rational amount of CS, independently on HS fraction, is 10 wt.%. The obtained WPCs have compressive stress at 10% of deformation in the range of (2.4–3.0) MPa, bending of (4.4–6.3) MPa and tensile strength of (0.23– 0.45) MPa. Additionally, the microstructural analysis shows that 10 wt.% of CS forms a sufficient amount of contact zones that strengthen the final product. The obtained average density (~319–408 kg/m3) indicate that, according to European normative document EN 316, WPCs can be classified as softboards and used as self-bearing structural material for building industry. Based on the requirements, WPCs can be applied in dry and humid conditions for the internal and external uses without loading (EN 622-4, section 4.2) or as load-bearing boards in dry and humid conditions for instantaneous or short-term load duration (EN 622-4, section 4.3).
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Thatte, Azam. "A New Type of Rotary Liquid Piston Pump for Multi-Phase CO2 Compression." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-77011.
Full textAbstract:
A novel rotary liquid piston multi-phase pump that transfers pressure energy from high pressure motive fluid stream to a low pressure process fluid stream within a high speed multi-ducted rotor is presented. The multiple ducts in the rotor act like cylinders of a rotating liquid piston pump with the liquid-to-liquid interface between the working fluid and the motive fluid acting like a piston. This novel pump has promise to solve challenges typically seen in multi-phase pumping and in trans-critical and supercritical CO2 compression systems, na m el y, risks due to phase change, two-phase compression inefficiencies, rotordynamic instabilities and sealing challenges etc. In this design the entrance and exit flow angles impart momentum to the rotor and the rotor achieves a self-sustained rotation without external power. The rotational speed dictates the volumetric efficiency, travel distance of the liquid piston within the ducts and the zero-mixing effectiveness of the design. This creates a very efficient pumping/compression system with just one moving part and three stationary parts, which can handle very high pressures and temperatures typical of supercritical CO2 turbomachines and also mitigates some of the rotordynamic stability challenges typically seen in MW-scale sCO2 turbomachinery designs. Ability of the pressure exchanger to dynamically maintain micro-scale gaps between rotor and stators through intelligent pressure balancing features relaxes the need to have complex dynamic seals. In this paper, use of this novel pump for multi-phase CO2 pumping application is explored through an advanced 3D multi-scale multi-phase flow model. The model captures the phase transport, compressibility, advection & diffusion of one phase into the other using a hybrid Eulerian-Lagrangian algorithm. Using these advanced models, performance curves are developed and results for key performance parameters including phase mixing, compressibility losses, effect of inlet gas volume fractions etc. are presented. A detailed transient evolution of two-phase fluid piston interface in the rotor ducts that captures acoustic wave propagation and reflection is presented. This new technology has promise to solve challenges typically seen in multi-phase pumping/ compression, transcritical and supercritical CO2 compression systems or in applications where the traditional pumps face steep challenges like phase change, erosive/ corrosive fluids, particle laden flows with high particle loading or flows with high gas volume fractions. This technology renders itself useful to several applications including supercritical CO2 turbomachines, waste pressure recovery, applications in oil & gas extraction and carbon sequestration etc.