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81.
Integrated water resources management practice is gaining popularity as an alternative water source due to the limited supply of freshwater. The present study was carried out on the photocatalytic degradation of Direct red 28 (DR-28) dye using magnetic nanoparticles (MNPs; Fe3O4) as a photocatalyst. The study was conducted on the photocatalytic degradation of DR-28 dye in synthetic dye effluent water, to understand the effects of different photoreaction parameters on the degradation kinetics. The influence of different parameters such as time, amount of photocatalyst, concentration of H2O2 and pH was investigated. At the optimum dosage of MNPs (0.6?g/L) with 4?mmol/L of H2O2, significant photocatalytic degradation of DR-28 dye (93.2%) was observed. The kinetic study revealed that the photocatalytic degradation followed pseudo-first-order kinetics. The degradation performance of Fe3O4 nanoparticles as a photocatalyst for DR-28 dye was compared with titanium dioxide (TiO2) and it was found that the performance of Fe3O4 as a photocatalyst is superior to TiO2 photocatalyst. The real dye effluent was also degraded at optimum conditions and promising results were achieved. 相似文献
82.
83.
We present an interferometric contrasting technique that allows visualizing the thickness and refractive index of a molecular film being part of an optical multilayer structure (etalon). Small wavelength shifts of the comblike etalon spectrum are transformed into measurable intensity variations using a second reference etalon (optical correlator), illuminated in series. A charge-coupled device camera acting as two-dimensional photometer is utilized to measure the optical spectral correlation (OSC) image. The performance of the here proposed optical spectral correlation method is demonstrated using very thin confined liquid films. We give a detailed signal-to-noise analysis. Subangstrom film thickness resolution is experimentally verified with single exposure images acquired at frame rates comparable to video standards (approximately 25 Hz). Finally, we describe the calibration procedures necessary to obtain an absolute quantification of the OSC image. 相似文献
84.
Marina Danalache Jasmin Knoll Walter Linzenbold Markus Enderle Tanja Abruzzese Arnulf Stenzl Wilhelm K. Aicher 《International journal of molecular sciences》2021,22(8)
Previously, we developed a novel, needle-free waterjet (WJ) technology capable of injecting viable cells by visual guided cystoscopy in the urethral sphincter. In the present study, we aimed to investigate the effect of WJ technology on cell viability, surface markers, differentiation and attachment capabilities, and biomechanical features. Porcine adipose tissue-derived stromal cells (pADSCs) were isolated, expanded, and injected by WJ technology. Cell attachment assays were employed to investigate cell–matrix interactions. Cell surface molecules were analyzed by flow cytometry. Cells injected by Williams Needle (WN), normal cannula, or not injected cells served as controls. Biomechanical properties were assessed by atomic force microscopy (AFM). pADSCs injected by the WJ were viable (85.9%), proliferated well, and maintained their in vitro adipogenic and osteogenic differentiation capacities. The attachment of pADSCs was not affected by WJ injection and no major changes were noted for cell surface markers. AFM measurements yielded a significant reduction of cellular stiffness after WJ injections (p < 0.001). WJ cell delivery satisfies several key considerations required in a clinical context, including the fast, simple, and reproducible delivery of viable cells. However, the optimization of the WJ device may be necessary to further reduce the effects on the biomechanical properties of cells. 相似文献
85.
Mary Jasmin Ang Sueun Lee Mai Wada Poornima D. E. Weerasinghe-Mudiyanselage Sung-Ho Kim Taekyun Shin Tae-Il Jeon Seung-Soon Im Changjong Moon 《International journal of molecular sciences》2021,22(11)
Changes in structural and functional neuroplasticity have been implicated in various neurological disorders. Sterol regulatory element-binding protein (SREBP)-1c is a critical regulatory molecule of lipid homeostasis in the brain. Recently, our findings have shown the potential involvement of SREBP-1c deficiency in the alteration of novel modulatory molecules in the hippocampus and occurrence of schizophrenia-like behaviors in mice. However, the possible underlying mechanisms, related to neuronal plasticity in the hippocampus, are yet to be elucidated. In this study, we investigated the hippocampus-dependent memory function and neuronal architecture of hippocampal neurons in SREBP-1c knockout (KO) mice. During the passive avoidance test, SREBP-1c KO mice showed memory impairment. Based on Golgi staining, the dendritic complexity, length, and branch points were significantly decreased in the apical cornu ammonis (CA) 1, CA3, and dentate gyrus (DG) subregions of the hippocampi of SREBP-1c KO mice, compared with those of wild-type (WT) mice. Additionally, significant decreases in the dendritic diameters were detected in the CA3 and DG subregions, and spine density was also significantly decreased in the apical CA3 subregion of the hippocampi of KO mice, compared with that of WT mice. Alterations in the proportions of stubby and thin-shaped dendritic spines were observed in the apical subcompartments of CA1 and CA3 in the hippocampi of KO mice. Furthermore, the corresponding differential decreases in the levels of SREBP-1 expression in the hippocampal subregions (particularly, a significant decrease in the level in the CA3) were detected by immunofluorescence. This study suggests that the contributions of SREBP-1c to the structural plasticity of the mouse hippocampus may have underlain the behavioral alterations. These findings offer insights into the critical role of SREBP-1c in hippocampal functioning in mice. 相似文献
86.
Reactive absorption using aqueous amine solutions is the technically most feasible retrofit option for the separation of CO2 from flue gases. Frequently discussed issues are the realization of a cost‐effective increase in efficiency in the sophisticated overall absorption process and the minimization of the energy demand for solvent regeneration under operating conditions. However, the influence of degradation phenomena on capacity and energy efficiency during the absorption‐regeneration cycles using blended monoethanolamine solutions has been less considered so far. The decrease in capacity depends in particular on time, temperature, O2‐ and SO2 concentration in the flue gas and has to be considered in plant design. Addition of degradation inhibitors decreases the energy requirements. 相似文献
87.
88.
The low-temperature geothermal potential of the flooded Gaspé Mines, near Murdochville, Québec, Canada, has been estimated from a long-term pumping test and numerical groundwater flow modelling. A former mining shaft was used to pump water for 3 weeks at a rate averaging 0.062 m3/s (3720 L/min). A mean recovery temperature equal to 6.7 °C and a maximum drawdown of 3.63 m were observed during this test. The observed drawdown was reproduced with a three-dimensional finite element model that simulates groundwater flow through the mine workings and surrounding rock mass. The model was then used to simulate longer-term pumping performed for heat recovery. Modelling results combined with a simplified energy balance calculation suggest that a sustainable energy extraction rate is attained at a pumping rate of 0.049 m3/s (2940 L/min), with a corresponding geothermal energy production potential of 765 kW, assuming a return water temperature of 3 °C. This energy could be extracted with heat pumps and used for space heating at the town's industrial park. 相似文献
89.
S. Yoon A. G. Panov R. G. Tonkyn A. C. Ebeling S. E. Barlow M. L. Balmer 《Catalysis Today》2002,72(3-4):243-250
The role of plasma processing on NOx reduction over γ-alumina and a basic zeolite, NaY was examined. During the plasma treatment NO is oxidized to NO2 and propylene is partially oxidized to CO, CO2, acetaldehyde, and formaldehyde. With plasma treatment, NO as the NOx gas, and a NaY catalyst, the maximum NOx conversion was 70% between 180 and 230 °C. The activity decreased at higher and lower temperatures.
As high as 80% NOx removal over gamma alumina was measured by a chemiluminescent NOx meter with plasma treatment and NO as the NOx gas.
For both catalysts a simultaneous decrease in NOx and aldehydes concentrations was observed, which suggests that aldehyde may be important components for NOx reduction in plasma-treated exhaust. 相似文献
90.
Electroencephalography and computerized transaxial tomography in patients with temporal lobe epilepsy 总被引:1,自引:0,他引:1
Computerized transaxial tomography was carried out on 112 patients with partial seizures with complex symptomatology. Structural abnormalities were defined in 33% of their studies: tumors in 8 patients, diffuse cerebral atrophy in 2, focal cortical atrophy in 27 and vascular abnormality in 1 case. 相似文献