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101.
102.
This paper presents an experimental study on the evaluation of thermal response of a spiral coil type GHE (ground heat exchanger). This GHE was installed on partially saturated landfill ground that was composed of silt and clay in the runway area of Incheon International airport. TRT (thermal response test) was conducted for more than 65 hours under continuous operation conditions. Ground thermal conductivity was derived based on line source theory, which has usually been found to be appropriate for line type GHEs such as U, W and 2U types. A reasonable method to derive ground thermal conductivity using the infinite line source theory for a spiral coil type GHE was introduced. Ground thermal conductivity from the TRT using spiral coil type GHE was compared with those from the analytical equivalent model of ground thermal conductivity. 相似文献
103.
Thi Ngoan Nguyen Hyeong Jin Joen Bong Hyeon Kwon Hyeong Hoon Kim Dai Lam Tran Karl Mortan Jeung Sang Go 《Journal of Materials Science》2014,49(13):4583-4589
This study presents a stable and controllable synthesis of fluorescent magnetic nanoparticles in a flow-through microchannel for the bimodal use of magnetic activated cells sorting and fluorescence-activated cell sorters. The La Mer process is carried out to synthesize magnetic nanoparticles using co-precipitation. Then, the magnetic nanoparticles are coated with conjugation of chitosan and fluorescent isothiocyanate with two different concentrations. The chemical composition of the magnetic nanoparticles is determined by comparing the standard X-ray diffraction peaks of Fe3O4, and their sizes are also examined by using field emission scanning electron microscopy and dynamic light scattering measurement. The magnetic property of saturation magnetization and coercive field is characterized in a vibrating sample magnetometer. Also, the possibility of external manipulation in the synthesis of the magnetic particles is demonstrated by separating the synthesized fluorescent magnetic nanoparticles into a non-reacting lamination flow. Finally, their fluorescence property is determined by measuring the fluorescence adsorption spectra and the photoluminescence emission spectra in UV–Vis spectroscopy. 相似文献
104.
A surface acoustic wave-based sample delivery and ionization method that requires minimal to no sample pretreatment and that can operate under ambient conditions is described. This miniaturized technology enables real-time, rapid, and high-throughput analysis of trace compounds in complex mixtures, especially high ionic strength and viscous samples that can be challenging for conventional ionization techniques such as electrospray ionization. This technique takes advantage of high order surface acoustic wave (SAW) vibrations that both manipulate small volumes of liquid mixtures containing trace analyte compounds and seamlessly transfers analytes from the liquid sample into gas phase ions for mass spectrometry (MS) analysis. Drugs in human whole blood and plasma and heavy metals in tap water have been successfully detected at nanomolar concentrations by coupling a SAW atomization and ionization device with an inexpensive, paper-based sample delivery system and mass spectrometer. The miniaturized SAW ionization unit requires only a modest operating power of 3 to 4 W and, therefore, provides a viable and efficient ionization platform for the real-time analysis of a wide range of compounds. 相似文献
105.
Nayeon Kim Chaeyeong Kim Soo Ho Ryu Go Oun Kim Jong-Sup Bae 《International journal of molecular sciences》2022,23(18)
Sparstolonin B (SsnB), which is found in Sparganium stoloniferum, prevents the synthesis of inflammatory mediators and is related to functional pathways of survival. In this study, we assessed the possible protective functions of SsnB on lipopolysaccharide (LPS)-induced inflammatory responses. We determined the functions of SsnB on controlling heme oxygenase (HO)-1, cyclooxygenase (COX-)2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). Furthermore, the distinct function of SsnB on the expression of iNOS and well-known pro-inflammatory mediators, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, were assessed in the pulmonary histological status of LPS-injected mice. SsnB upregulated the HO-1 production, inhibited luciferase-NF-κB interaction, and lowered COX-2/PGE2 and iNOS/NO, which lead to the reduction of STAT-1 phosphorylation. Moreover, SsnB enhanced the nuclear translocation of Nrf2, elevated the binding activity between Nrf2 and antioxidant response elements (AREs), and weakened IL-1β expression on LPS-treated HUVECs. SsnB-suppressed iNOS/NO synthesis was restored by the process of the RNAi inhibition of HO-1. In experiment with an LPS-injected animal model, SsnB remarkably decreased the iNOS expression in the pulmonary biostructure and TNF-α level in the bronchoalveolar lavage fluid (BALF). Therefore, these results demonstrate that SsnB is responsible for inflammation ameliorative activity by controlling iNOS through inhibition of both NF-κB expression and p-STAT-1. Therefore, SsnB could be a candidate for promoting novel clinical substances to remedy pathologic inflammation. 相似文献
106.
Go Oun Kim Nayeon Kim Gyu Yong Song Jong-Sup Bae 《International journal of molecular sciences》2022,23(18)
Sepsis is an uncontrolled response to inflammatory infection and is associated with high levels of mortality and morbidity. Rg4 is a rare ginsenoside mainly found in the leaves of Panax ginseng C. A. Meyer and the major protopanaxatriol-type ginsenoside of black ginseng. In this study, we determined whether Rg4 affects cecal ligation and puncture (CLP)-induced sepsis. Animals were separated into the following six groups: control group, CLP-operated group, CLP plus maslinic acid (MA), and CLP plus Rg4 (5, 10, or 15 mg/kg). Survival rate, body weight changes, inflammatory cytokines, and histological analyses were assessed. Human endothelial cells were activated with the high-mobility group box 1 (HMGB1) protein and Rg4. Cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Enzyme-linked immunosorbent assay (ELISA) and Western blot analysis were used to assess inflammation and gene expression, respectively. After CLP surgery, the Rg4-administered group exhibited a higher survival rate and body weight compared with the untreated control group. Rg4 treatment reduced cytokine levels, including tumor necrosis factor (TNF)-α and interleukin (IL)-1β, as well as nitric oxide (NO) levels and renal inflammation. After Rg4 treatment of HMGB1-activated cells, the expressions of toll-like receptor (TLR) 4 and TNF-α were decreased, and the activation of phosphoinositide 3-kinase (PI3K)/AKT signaling increased cell viability. In summary, Rg4 inhibited inflammation and exhibited a protective effect against CLP-induced sepsis, thereby reinforcing cell survival against septic responses. 相似文献
107.
In order to solve a power consumption problem of the driver stage in the cathode-follower RF system, a grid-cathode driving scheme is investigated by means of an isolation transformer. A very low output impedance can be realized together with a voltage gain a few tens of times higher than that of a cathode-follower. The model system has been tested under frequency modulation in the 1-3-MHz range at 40-Hz repetition; the output impedance is less than 30 Ω and the driver voltage 62 V to produce a 1.2-kV peak at the cavity gap 相似文献
108.
Clinical experience of arthroscopy in 12 temporomandibular joints with a clinical diagnosis of closed lock was described. There were 10 patients and all were females with a mean age of 31.2 years (range 20 to 59 years). The antero-lateral approach was used for entry into 11 joints. The clinical findings were adhesions (64%), fibrillation (64%), anterior displacement of disc (36%) and scuffing of the articular surface of the glenoid fossa (9%). Two of the joints that had arthrocentesis prior to arthroscopy did not show any different findings from the rest. Of the 8 patients who had pre-arthroscopy pain, 7 patients (88%) had reduction of the symptom. Three patients (38%) had complete resolution of pain. The range of mouth opening (measured as maximal incisor opening) increased in all patients two weeks following arthroscopy. The average change in maximal incisor opening was 40.3% with a range of 22% to 85%. The mean follow-up was 34 months (range 4 to 68 months). 相似文献
109.
110.
Ludwig J Gauckler Martin Go¨dickemeier Daniel Schneider 《Journal of Electroceramics》1997,1(2):165-172
Ceria solid solutions are potential electrolytes for solid oxidefuel cells (SOFC). At the anode side of SOFCs at low oxygen partialpressures ceria is partially reduced. The nonstoichiometry ofCeO2-x solid solutions with 20 mol%SmO1.5, 20 mol% GdO1.5 and 10 mol%CaO were investigated by isothermal coulometric titration in a zirconia cellin the temperature range from 700 to 900°C and in the oxygen partialpressure range from 10-12 to 10-25 atm. Theresults of the 3 different compositions at 900°C are comparable to thosefor pure ceria. At lower temperatures, pure ceria is more stable againstreduction than ceria solid solutions. The dependence of nonstoichiometry onoxygen partial pressure suggests a defect model with oxygen vacancies andtheir associates with reduced cerium cations and dopant cations. Low oxygennonstoichiometries of x = 0.005 to 0.008 can be expected for ceria solidsolutions at 700° under SOFC operating conditions. 相似文献