Surface functionalization of silicon substrates via graft polymerization

Ph.DDOCTOR OF PHILOSOPH

Morris Water Maze Test for Learning and Memory Deficits in Alzheimer's Disease Model Mice

The Morris Water Maze (MWM) was first established by neuroscientist Richard G. Morris in 1981 in order to test hippocampal-dependent learning, including acquisition of spatial memoryand long-term spatial memory 1. The MWM is a relatively simple procedure typically consisting of six day trials, the main advantage being the differentiation between the spatial (hidden-platform) and non-spatial (visible platform) conditions 2-4. In addition, the MWM testing environment reduces odor trail interference 5. This has led the task to be used extensively in the study of the neurobiology and neuropharmacology of spatial learning and memory. The MWM plays an important role in the validation of rodent models for neurocognitive disorders such as Alzheimer’s Disease 6, 7. In this protocol we discussed the typical procedure of MWM for testing learning and memory and data analysis commonly used in Alzheimer’s disease transgenic model mice

Bioinspired heat exchangers based on triply periodic minimal surfaces for supercritical CO2 cycles

The supercritical carbon dioxide (sCO2) based Brayton cycle is a proposed alternative to replace conventional Rankine cycles in terms of high cycle efficiency, compact turbomachinery and heat exchangers. In the sCO2 cycle, however, the existing heat exchangers have been challenged by large portion of heat transfer (approximately 60–70% of total cycle heat transfer) and high cycle efficiency required. In the present study, two novel heat exchangers were proposed by utilizing triply periodic minimal surface (TPMS) structures. i.e. the Gyroid structure and Schwarz-D surface, to enhance heat transfer and improve cycle efficiency. TPMS structures are a class of structures composed of two distinct inter-penetrating volume domains separated by an area-minimizing wall, which have been observed as biological membranes and co-polymer phases. Two heat exchangers along with a reference printed circuit heat exchanger (PCHE) were investigated numerically by computational fluid dynamics simulations when the hot and cold sCO2 fluids pass through them at various Reynolds numbers. Effects of geometrical shapes and Reynolds number on the hydraulic and thermal performances were identified. It was demonstrated that two heat exchangers with TPMS can improve overall thermal performance by 15–100%, and the Nusselt number is raised by 16–120% for a given pumping power in comparison with the PCHE. Hence, heat exchangers with TPMS have a very good potential to enhance sCO2 cycle efficiency

High performance interrogation by a composite-double-probe-pulse for ultra-weak FBG array

We propose and experimentally demonstrate a technique using a composite-double-probe-pulse (CDPP) to eliminate the effect of polarization fading for phase-sensitive optical time-domain reflectometry (Φ-OTDR) based on ultra-weak FBG (UWFBG) array. The CDPP is composed of two optical pulses whose spatial interval is equal to twice the spatial interval of adjacent UWFBGs in the UWFBG array. One optical pulse is a long optical pulse, and the other optical pulse is composed of two continuous short optical pulses, whose polarization states are orthogonal to each other. The width of the short pulse is equal to half of the width of the normal pulse and their frequencies are different from the long pulse. By using such a method to perform the sensing for the UWFBG array, distributed quantitative measurement can be realized with only direct detection scheme and the influence of polarization fading in the demodulation of signal is thoroughly eliminated

Reconstruction of mandibular defects using vascularized fibular osteomyocutaneous flap combined with nonvascularized fibular flap

The height of single-layer fibular flap is not long enough to return to the ideal height of the mandible. While the double-layer vascularized fibular osteomyocutaneous flap(VFF) is more complicated in shaping and fixation, along with a longer operation time. The aim of this study was to investigate the clinical effect of VFF combined with nonvascularized fibular flap(NVFF) in the reconstruction of mandibular defect. From September 2016 to June 2018, 15 patients with benign mandibular tumors underwent reconstruction with VFF and NVFF. SimPlant Pro ? software (version 11.04) was used to simulate reconstruction of the mandible preoperatively. All patients were followed up for 8-23 month, with an average of 11.7 months. 15 VFFs survived well. Among the 15 NVFFs, one was almost completely absorbed, two with partial absorption, and the remaining survived regardless of the small amount of absorption. The postoperative absorption of the whole fibula was 7.53±6.362%, a favorable facial contour and speech function were attained. The VFF combined with NVFF to reconstruct the mandibular defect can restore the vertical height of the mandible and achieve satisfactory clinical results

1,2-Di-tert-butyl­ethane-1,2-diyl bis­(tert-butane­sulfinamide)

In the title compound, C18H40N2O2S2, a vicinal diamine derivative, the crystal structure is stabilized by two intra­molecular N—H⋯O hydrogen bonds. The distance between the two kernel chiral C atoms is 1.580 (2) Å

Heat transfer enhancement of water-cooled triply periodic minimal surface heat exchangers

Whether triply periodic minimal surface (TPMS) heat exchangers are applicable to cooling or cold storage systems as a cooler for supercritical carbon dioxide (SCO2) is undocumented. Here the conjugated heat transfer of SCO2 in TPMS Schoen-G heat exchanger and printed circuit heat exchanger (PCHE) was predicted based on three-dimensional steady turbulent Reynolds-averaged Navier-Stokes equations, energy equation and shear stress transport model using computational fluid dynamics software ANSYS CFX when SCO2 inlet temperature and pressure vary in 65-30 ℃ and (8-9)MPa. SCO2 in two heat exchangers is cooled under counter-flow conditions by a stream of cold water with given inlet temperature and mass flow rate. It was shown that the mean heat transfer coefficient of SCO2 in TPMS Schoen-G heat exchanger is larger than PCHE. As the inlet pressure rises, the friction factor increases and Nusselt number decreases in the heat exchangers due to decreased Reynolds number and Prandtl number, respectively. The friction factor ratio, Nusselt number ratio and performance evaluation criterion vary in the range of 0.38-0.50, 1.07-1.49, and 1.45-2.04 with Reynolds number and inlet temperature when the PCHE serves as a reference heat exchanger. The streamlines in TPMS Schoen-G heat exchanger are quite smooth even though the areas with a higher velocity appear. The streamlines in PCHE exhibit a spiral flow pattern to result in extra hydraulic loss. The heat transfer enhancement of TPMS Schoen-G heat exchanger is much better TPMS Schwarz-D heat exchanger at a Reynolds number higher than 16,000. The enhancement is attributed to a larger heat transfer surface area and more topological tortuosity without flow separation than PCHE

Pyrolysis treatment of nonmetal fraction of waste printed circuit boards : Focusing on the fate of bromine

Advanced thermal treatment of electronic waste offers advantages of volume reduction and energy recovery. In this work, the pyrolysis behaviour of nonmetallic fractions of waste printed circuit boards was studied. The fate of a bromine and thermal decomposition pathway of nonmetallic fractions of waste printed circuit boards were further probed. The thermogravimetric analysis showed that the temperatures of maximum mass loss were located at 319°C and 361°C, with mass loss of 29.6% and 50.6%, respectively. The Fourier transform infrared Spectroscopy analysis revealed that the spectra at temperatures of 300°C–400°C were complicated with larger absorbance intensity. The nonmetallic fractions of waste printed circuit boards decomposed drastically and more evolved products were detected in the temperature range of 600°C–1000°C. The gas chromatography–mass spectrometry analysis indicated that various brominated derivates were generated in addition to small molecules, such as CH4, H2O and CO. The release intensity of CH4 and H2O increased with temperature increasing and reached maximum at 600°C–800°C and 400°C–600°C. More bromoethane (C2H5Br) was formed as compared with HBr and methyl bromide (CH3Br). The release intensity of bromopropane (C3H7Br) and bromoacetone (C3H5BrO) were comparable, although smaller than that of bromopropene (C3H5Br). More dibromophenol (C6H4Br2O) was released than that of bromophenol (C6H5BrO) in the thermal treatment. During the thermal process, part of the ether bonds first ruptured forming bisphenol A, propyl alcohol and tetrabromobisphenol A. Then, the tetrabromobisphenol A decomposed into C6H5BrO and HBr, which further reacted with small molecules forming brominated derivates. It implied debromination of raw nonmetallic fractions of waste printed circuit boards or pyrolysis products should be applied for its environmentally sound treating.© 2020 Sage. The article is protected by copyright and reuse is restricted to non-commercial and no derivative uses. Users may also download and save a local copy of an article accessed in an institutional repository for the user's personal reference.fi=vertaisarvioitu|en=peerReviewed