Reconstruction of the polyamide film in nanofiltration membranes via the post-treatment with a ternary mixture of ethanol-water-NaOH: Mechanism and effect

Desalination ◽  
2021 ◽  
Vol 519 ◽  
pp. 115317
Author(s):  
Ruijun Zhang ◽  
Song Su ◽  
Shanshan Gao ◽  
Jiayu Tian
1996 ◽  
Vol 34 (7-8) ◽  
pp. 445-453 ◽  
Author(s):  
G. Baumgarten ◽  
C. F. Seyfried

The leachate treatment plant of the landfill in Mechernich including biological pretreatment, reverse osmosis and evaporation and drying of the concentrate has been in operation since the beginning of 1994. Originally the plant was designed for a capacity of 130 m3/d. In the future, an average leachate amount of ca. 280 m3/d and even considerably higher montly peaks must be assumed. The necessary enlargement of the biological pretreatment will be realized by a second biological contactor plant. Corresponding to the operation of the existing plant a large amount of the ammonium can be eliminated under aerobic conditions by deammonification so no enlargement of the denitrification stage is needed. by simply replacing the reverse osmosis membranes by nanofiltration membranes, an operational capacity of ca. 280 m3/d may easily be achieved at the existing physical post-treatment stage. With the aid of this enlargement conception, the relatively high operational costs at present will be reduced considerably.


2011 ◽  
Vol 50 (8) ◽  
pp. 4678-4685 ◽  
Author(s):  
Yan Zhang ◽  
Yanlei Su ◽  
Wenjuan Chen ◽  
Jinming Peng ◽  
Yanan Dong ◽  
...  

Proceedings ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 27
Author(s):  
Ewa Puszczało ◽  
Anna Marszałek

The aim of the research presented in this article was to present the possibilities of wastewater treatment coming from the confectionery plant using pressure membrane techniques. Nanofiltration was carried out in a pressure dead-end filtration set up (Osmonics type GH-100-400) with a cell capacity of 350 cm3 equipped with a magnetic stirrer. Four flat nanofiltration membranes were used during the tests. The efficiency of the process was estimated by determining the purified wastewater volumetric stream and based on the removal degree of pollution load. The nanofiltration membrane, thanks to which the highest cleaning results were obtained, is a flat composite membrane, with the symbol NF-270, with the polyamide film layer of the Dow Filmtec company. The degree of removal of COD after nanofiltration in this membrane was 98.7%. It was found, that wastewater treated by pressure membrane techniques in the confectionery industry can be reused, for example, for irrigation of agricultural land or gardens, and for machines and equipment washing (closing water circuits). The use of NF processes enables wastewater treatment to such a degree that it can be drained to a natural receiver.


Author(s):  
Amreek Singh ◽  
Judith M. McLaren ◽  
Onkar S. Atwal ◽  
Peter Eyre

Introduction3-methylindole (MI), a rumen metabolite of the amino acid L-tryptophan, has been shown to produce bovine pulmonary edema and emphysema. The airways contain free and exfoliated cells. A morphologic analysis of these cells may complement the understanding of the mechanism of lung edema. Ultrastructure of the bronchopulmonary lavage (BL) cells 24 h following MI oral administration to calves is described in this experiment. The 12 hours post-treatment results were described earlier.Materials and MethodsTwo Holstein-Friesian calves were each administered an oral dose of 0.2 g MI/Kg body weight and another two calves served as controls. The animals were euthanized with sodium pentabarbitol 24 h after receiving the compound. The lungs and trachea were removed and 0.1 M sodium phosphate buffered saline was infused into the lungs through the trachea. Glutaraldehyde fixative was added to the recovered BL fluid so as to form a 1% solution. The fluid was centrifuged and the resulting cell pellet was suspended in the buffer. The procedures were repeated on the suspension; the pellet was post-fixed in osmium tetroxide and was processed by conventional methods of section preparations for TEM examination. Lung samples from caudal lobes were fixed in 1.5% glutaraldehyde to obtain tissue sections for TEM.Results and DiscussionPulmonary alveolar macrophages (AM), neutrophils, ciliated epithelial cells, globule leukocytes and plasma cells were recovered from the BL fluid of the control and Mi-administered calves. Ciliated cells and globule leukocytes could not be harvested from the controls. The AM obtained from the treated calves (Fig. 1) in comparison with similar cells from the controls were larger, and contained large membrane-limited inclusions (phagolysosomes). There was a remarkable similarity between the lavaged AM and the AM studied in thin sections of lung (cf. Fig. 1 and Fig. 2). The neutrophil was the second most abundant cell type retrieved from the lavage fluid from the calves of control or treated group. Except for scanty pseudopodia in the neutrophils obtained from the Mi-receiving calves, the cells appeared unaltered (Fig. 3). Ciliated cells were abundant in the BL fluid of Mi-ingesting calves. A heterogeneous collection of vesicles filled the ciliated cell cytoplasm (Fig. 3). Globule leukocytes were commonly observed among BL cells of treated calves. The globule leukocytes were ca. 15 μm in diameter and contained round or elliptical nuclei with conspicuous nucleoli. The cytoplasmic granules, which are a prominent feature of globule leukocytes, were electron-opaque and had a variable diameter (0.5-3.0 μm). A one-line account of globule leukocytes in the bronchi of steers administered MI has appeared. Plasma cells were rare. Ultrastructure of BL cells is compatible with their response to chemical insult by MI.


2014 ◽  
Vol 24 (2) ◽  
pp. 48-58 ◽  
Author(s):  
Lakshmi Kollara ◽  
Graham Schenck ◽  
Jamie Perry

Studies have investigated the applications of Continuous Positive Airway Pressure (CPAP) therapy in the treatment of hypernasality due to velopharyngeal dysfunction (VPD; Cahill et al., 2004; Kuehn, 1991; Kuehn, Moon, & Folkins, 1993; Kuehn et al., 2002). The purpose of this study was to examine the effectiveness of CPAP therapy to reduce hypernasality in a female subject, post-traumatic brain injury (TBI) and pharyngeal flap, who presented with signs of VPD including persistent hypernasality. Improvements in mean velopharyngeal orifice size, subjective perception of hypernasality, and overall intelligibility were observed from the baseline to 8-week post-treatment assessment intervals. Additional long-term assessments completed at 2, 3, and 4 months post-treatment indicated decreases in immediate post-treatment improvements. Results from the present study suggest that CPAP is a safe, non-invasive, and relatively conservative treatment method for reduction of hypernasality in selected patients with TBI. More stringent long-term follow up may indicate the need for repeated CPAP treatment to maintain results.


2019 ◽  
Vol 89 (1-2) ◽  
pp. 5-12
Author(s):  
Alon Harris ◽  
Brent Siesky ◽  
Amelia Huang ◽  
Thai Do ◽  
Sunu Mathew ◽  
...  

Abstract. Introduction: To investigate the effects of a lutein complex supplementation on ocular blood flow in healthy subjects. Materials and Methods: Sixteen healthy female patients (mean age 36.8 ± 12.1 years) were enrolled in this randomized, placebo-controlled, double-blinded, two-period crossover study. Subjects received daily an oral dose of the lutein with synergistic phytochemicals complex (lutein (10 mg), ascorbic acid (500 mg), tocopherols (364 mg), carnosic acid (2.5 mg), zeaxanthin (2 mg), copper (2 mg), with synergistic effects in reducing pro-inflammatory mediators and cytokines when administered together in combination) and placebo during administration periods. Measurements were taken before and after three-week supplementation periods, with crossover visits separated by a three-week washout period. Data analysis included blood pressure, heart rate, intraocular pressure, visual acuity, contrast sensitivity detection, ocular perfusion pressure, confocal scanning laser Doppler imaging of retinal capillary blood flow, and Doppler imaging of the retrobulbar blood vessels. Results: Lutein complex supplementation produced a statistically significant increase in mean superior retinal capillary blood flow, measured in arbitrary units (60, p = 0.0466) and a decrease in the percentage of avascular area in the superior (−0.029, p = 0.0491) and inferior (−0.023, p = 0.0477) retina, as well as reduced systolic (−4.06, p = 0.0295) and diastolic (−3.69, p = 0.0441) blood pressure measured in mmHg from baseline. Data comparison between the two supplement groups revealed a significant decrease in systemic diastolic blood pressure (change from pre- to post-treatment with lutein supplement (mean (SE)): −3.69 (1.68); change from pre- to post-treatment with placebo: 0.31 (2.57); p = 0.0357) and a significant increase in the peak systolic velocity (measured in cm/sec) in the central retinal artery (change from pre- to post-treatment with lutein supplement: 0.36 (0.19); change from pre- to post-treatment with placebo: −0.33 (0.21); p = 0.0384) with lutein complex supplement; data analyses from the placebo group were all non-significant. Discussion: In healthy participants, oral administration of a lutein phytochemicals complex for three weeks produced increased ocular blood flow biomarkers within retinal vascular beds and reduced diastolic blood pressure compared to placebo.


2014 ◽  
Vol 84 (3-4) ◽  
pp. 0140-0151 ◽  
Author(s):  
Thilaga Rati Selvaraju ◽  
Huzwah Khaza’ai ◽  
Sharmili Vidyadaran ◽  
Mohd Sokhini Abd Mutalib ◽  
Vasudevan Ramachandran ◽  
...  

Glutamate is the major mediator of excitatory signals in the mammalian central nervous system. Extreme amounts of glutamate in the extracellular spaces can lead to numerous neurodegenerative diseases. We aimed to clarify the potential of the following vitamin E isomers, tocotrienol-rich fraction (TRF) and α-tocopherol (α-TCP), as potent neuroprotective agents against glutamate-induced injury in neuronal SK-N-SH cells. Cells were treated before and after glutamate injury (pre- and post-treatment, respectively) with 100 - 300 ng/ml TRF/α-TCP. Exposure to 120 mM glutamate significantly reduced cell viability to 76 % and 79 % in the pre- and post-treatment studies, respectively; however, pre- and post-treatment with TRF/α-TCP attenuated the cytotoxic effect of glutamate. Compared to the positive control (glutamate-injured cells not treated with TRF/α-TCP), pre-treatment with 100, 200, and 300 ng/ml TRF significantly improved cell viability following glutamate injury to 95.2 %, 95.0 %, and 95.6 %, respectively (p < 0.05).The isomers not only conferred neuroprotection by enhancing mitochondrial activity and depleting free radical production, but also increased cell viability and recovery upon glutamate insult. Our results suggest that vitamin E has potent antioxidant potential for protecting against glutamate injury and recovering glutamate-injured neuronal cells. Our findings also indicate that both TRF and α-TCP could play key roles as anti-apoptotic agents with neuroprotective properties.


1997 ◽  
Vol 13 (2) ◽  
pp. 118-130 ◽  
Author(s):  
Juan I. Capafóns ◽  
Carmen D. Sosa ◽  
Manuel Herrero ◽  
Conrado Viña

The results are presented for the validation of a videotape as an analogous situation for a flight. The video includes the most significant elements of a flight by air: confirmation of the flight, packing, going to the airport, checking-in, going through the metal-detector, departure lounge, boarding the plane, demonstration of the personal safety drills, interiors and exteriors during the flight and landing. Two physiological measures are used for validation (heart rate and temperature) and a subjective measure (situational anxiety, SA). The results (both t-tests and the discriminant analysis) indicate that the videotape is able to discriminate between phobics and non-phobics of flying in the three variables considered. With respect to sensitivity in detecting change produced by various treatments in clients with phobia of flying, the results are also satisfactory. A greater differentiation is produced between the pre-post treatment measures, both in subjective and in the physiological measures.


Sign in / Sign up

Export Citation Format

Share Document