13 results on '"EREN, HÜSEYİN"'
Search Results
2. Comparison of the colour fading effects of sodium hypochlorite and ozone treatments.
- Author
-
Yiğit, İdil, Eren, Semiha, Karalı, Recep, Yıbar, M. Fahri, and Eren, Hüseyin Aksel
- Subjects
NATURAL dyes & dyeing ,SODIUM hypochlorite ,OZONE ,CHEMICAL oxygen demand ,WATER conservation ,SCANNING electron microscopy ,COLOR ,OPTICALLY stimulated luminescence - Abstract
Colour fading is a method that is used to achieve a vintage look in textile goods. It is desired by customers in the textile market. Additionally, customers demand that these types of products are produced by environmentally friendly methods. In this study, sodium hypochlorite and ozone were used as laboratory‐scale colour fading reagents on dyed cotton fabrics. Cotton fabrics were dyed with four different primary colours: red, yellow, blue and black. Dyed fabrics were subjected to ozone and sodium hypochlorite treatment under different treatment conditions. Ozone was chosen as an alternative for comparison and it was applied at fixed flow rate (5 L/min) and time (10 minutes). Colour differences, chemical oxygen demand, bursting strength and energy, water and chemical consumptions were measured. The surface morphology was characterised by scanning electron microscopy. We can conclude that ozonation is effective in discharging colour from dyed fabric samples, and the colour‐fading effect is uniform, like in sodium hypochlorite treatment. It was observed that both processes are similar in terms of strength and surface modification. Results showed a 90% cost reduction, 85% water conservation and a 26% chemical oxygen demand reduction. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
3. An investigation of process parameters on colour during the dyeing of polyester in supercritical carbon dioxide media.
- Author
-
Yiğit, İdil, Eren, Semiha, Özcan, Hande, Avinc, Ozan, and Eren, Hüseyin Aksel
- Subjects
NATURAL dyes & dyeing ,SUPERCRITICAL carbon dioxide ,DYES & dyeing ,POLYESTERS ,COLOR ,ENERGY consumption - Abstract
Innovative supercritical carbon dioxide (scCO2) treatment conditions in fluidised media technology were examined for polyester dyeing. The different dyeing processes in scCO2 media were carried out under a constant dyeing temperature of 120°C (at pressures ranging from 9 to 29 MPa), a constant pressure of 25 MPa (at dyeing temperatures ranging from 40 to 140°C) and a constant density range of 500‐550 kg/m3 (at combinations of dyeing temperatures ranging from 80 to 130°C and dyeing pressures ranging from 18 to 28 MPa). The constant dyeing temperature, constant dyeing pressure and constant density (120°C, 25 MPa, 500‐550 kg/m3, respectively) were selected according to the best results in the literature and recommendations from industrial applications for polyester dyeing in scCO2 media. The different conditions of the studied parameters and their influence are discussed. Colour difference (ΔE) and colour strength (K/S), as well as washing fastness and bursting strength properties, were investigated and compared. Acceptable colour properties (similar to those for standard [control reference] fabric: dyed in scCO2 media at 120°C, 25 MPa pressure and 506 kg/m3 density for 90 minutes) on polyester fabric, with commercially acceptable and quite high washing fastness levels and comparable bursting strength values (similar to those for standard fabric without significant or drastic strength loss), could be achieved with the following scCO2 dyeing processes: at a lower dyeing pressure with the same dyeing temperature (in scCO2 media at 120°C, 21 MPa pressure and 423 kg/m3 density for 90 minutes), at a lower dyeing temperature with the same dyeing pressure (in scCO2 media at 100°C, 25 MPa pressure and 588 kg/m3 density for 90 minutes) and at both a lower dyeing pressure and a lower dyeing temperature with a constant density range of 500‐550 kg/m3 (in scCO2 media at 110°C, 24 MPa pressure and 526 kg/m3 density for 90 minutes). Satisfactory and successful dyeing properties and performance similar to polyester fibre dyed under standard scCO2 dyeing conditions with less energy consumption could be achieved with the correct scCO2 dyeing process parameter optimisation. For instance, the dyeing process in the scCO2 environment at the same dyeing temperature with the standard scCO2 dyeing process (at 120°C), but with a lower dyeing pressure (at 21 vs 25 MPa), resulted in a 17 kWh decrease in energy consumption. In conclusion, it is very important to choose the correct dyeing pressure to obtain level dyeing in the polyester dyeing process carried out in a scCO2 environment and to achieve a reduction in energy consumption during dyeing in a scCO2 medium. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
4. Ozone utilisation for discharge printing of reactive dyed cotton.
- Author
-
Yigit, Idil, Eren, Semiha, and Eren, Hüseyin Aksel
- Subjects
GAS flow ,DYES & dyeing ,CHEMICAL oxygen demand ,SODIUM hydroxide ,TEXTILE finishing - Abstract
Environmental pollution is one of the major concerns of the textile finishing sector. The reduction or substitution of the harsh chemicals used during dyeing and printing processes is necessary. In this study, the use of ozone for the discharge printing process was examined in order to substitute the use of reductive agent and caustic soda by ozone gas. The reactive dyed cotton samples were wetted by water and some selected solutions at 25%, 40% and 60% pick up were used and subjected to ozone gas treatment. The gas flow rates were 5 and 10 l/min for 5 and 10 min treatment times, respectively. The results were compared with that of conventional discharge printed samples. Colour discharge (%), colour difference (ΔE), strength, washing and rubbing fastness and chemical oxygen demand (COD) values were compared and reported. Colour discharge increased at higher gas flow rates and prolonged treatment times. Although ozone printing could not attain the contour sharpness of conventional discharge printing, the addition of selected chemicals affected colour discharge and the contour sharpness. Strength tests did not show a significant decrease when using ozone treatment. Fastness tests results (washing and rubbing) were slightly higher compared with conventional discharge printed samples. COD values were much lower for ozone treatment compared with conventional discharge printing effluent. Consequently, it was demonstrated that ozone may be an environmentally friendly substitute for discharge printing. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
5. Application of ozone gas for the stripping of fabric ink-jet-printed with reactive dyes.
- Author
-
Kıcık, Hülya and Eren, Hüseyin Aksel
- Subjects
INK-jet printing ,REACTIVE dyes ,TEXTILE printing ,INK-jet printers ,THIOUREA ,CHEMICAL oxygen demand - Abstract
In this study, a novel process utilizing ozone was carried out for colour stripping of fabrics misprinted with reactive dyes in ink-jet machines. The results of ozone applications were compared with conventional colour stripping process performed by thiourea dioxide ( TUDO) and soda ash. In trials, cotton-based and viscose-based woven fabrics were used as these fabrics were the most utilized at the textile mill in which this study was performed. Different ozone treatment times (30, 45, 60 or 90 min) were tested to find optimum process time and it was found that process times depended on fabric type. Particularly, colour stripping on high density and thick fabrics were harder than low density and thin fabric types. Fabric strengths, whiteness indexes and chemical oxygen demand ( COD) values were measured. Also energy, chemical and water consumptions were calculated. Consequently, it was found that the reduction of the COD value of effluent was up to 98%. The calculations showed that the savings in time and cost in ozone treatment were up to 77%. Satisfactory colour stripping and tensile strengths were achieved. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
6. Colour stripping of reactive-dyed cotton by ozone treatment.
- Author
-
Eren, Semiha, Gümüs, Buse, and Eren, Hüseyin Aksel
- Subjects
DYES & dyeing ,COTTON textiles ,OZONE ,CHEMICAL oxygen demand ,STRIPPERS (Chemical technology) - Abstract
Trials have been carried out to investigate the efficiency of ozone treatment in the colour stripping of reactive-dyed cotton fabrics. The trials were performed on a specially designed apparatus to inject ozone gas into the liquor passing through a perforated beam with fabric rolls on it, just like a beam dyeing machine with ozone venturi injection. Conventional reductive colour stripping was applied as the control treatment, and ozone treatment was applied for three different application times (15, 30, and 45 min). Trials were performed with seven selected reactive dyes having various chromophores and reactive groups. The results indicate that 45 min ozone treatment yielded the best colour stripping results among the three application times. Furthermore, the colour stripping percentages of the 45 min ozone treatment were higher for four of the tested dyes, the same for one of the tested dyes, and lower for two of the tested dyes compared with the control treatment, which consisted of conventional reductive colour stripping. Colour stripping of 90% and above was achieved for all samples of the 45 min ozone treatment. The chemical oxygen demand values of the colour stripping baths were compared: the average value of the 45 min ozone application baths was 105 mg l
−1 , and it was 1993 mg l−1 for the conventional reductive treatment baths. Consequently, a reduction in chemical oxygen demand of almost 94% was achieved by ozone treatment compared with conventional reductive treatment. The strength values of the fabrics after the respective treatments were similar, with a difference of only 3%. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
7. Practical realisation of ozone clearing after disperse dyeing of polyester.
- Author
-
Gundogan, Seda and Eren, Hüseyin Aksel
- Subjects
POLYESTERS ,DYES & dyeing ,TEXTILE dyeing ,PROTOTYPES ,OZONE generators - Abstract
In this study, a novel system utilising ozone in jet dyeing machines is introduced, and the results of ozone-clearing treatments of disperse dyed polyester on the prototype modified machine are reported. A Venturi injector was mounted on the liquor circulation pipe of the jet dyeing machine to feed ozone gas into the machine. Ozone was generated via an ozone generator by feeding conditioned air into the generator. The ozone gas entering the pipe partly dissolved in the treatment liquor; the dissolved portion and the gaseous ozone interacted via the fabric in the pipe, especially in the nozzle and also at the bottom of the autoclave (machine body). Disperse dyed polyester fabrics of textile-company mass production were ozone cleared in this prototype. Ozone clearing was achieved in cold water (room temperature), and no other chemicals were used. The colour of the samples, wet fastness properties, and the chemical oxygen demand of the effluent were investigated, and costs were compared with those of conventional reduction clearing of ozone. Results were outstanding: an 83% cost reduction, 67% timesaving, and an 88% COD reduction were achieved. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
8. Ozone applications for after-clearing of disperse-dyed poly(lactic acid) fibres.
- Author
-
Avinc, Ozan, Eren, Hüseyin Aksel, and Uysal, Pınar
- Subjects
OZONE ,POLYLACTIC acid ,DYES & dyeing ,CHEMICAL oxygen demand ,COLOR - Abstract
In this study, the effectiveness of the ozonation process, in neutral distilled water at room temperature, as a clearing process for disperse-dyed poly(lactic acid) fibre fabrics is investigated. The efficiency of simultaneous decolorisation of dyebath effluent and clearing of dyed poly(lactic acid) in the cooled dyebath after completion of the poly(lactic acid) dyeing cycle is also explored. Conventional alkaline reduction clearing with sodium dithionite was chosen as a control clearing process for comparison. Wash fastness, colour difference, colour removal (in Hazen) and chemical oxygen demand values were determined and compared. Long ozone treatment times at high ozone dose resulted in unacceptable colour differences. The colour difference problem was solved by use of lower ozone dose; however, a warm soaping step had to be added to the after-clearing sequence in order to achieve the desired fastness properties. A 33% reduction on the chemical oxygen demand load of the total process (dyeing + after-clearing) could be achieved by ozone after-clearing instead of using a conventional reduction clearing treatment. The addition of the warm soaping step to improve the fastness properties of the ozonated samples increased the total chemical oxygen demand of the process (dyeing + ozonation in water + warm soaping), but a 12-18% reduction on the chemical oxygen demand load of the total process was observed when compared with the conventional treatment sequence (dyeing + reduction clearing). [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
9. Comparison of different ultrasound support methods during colour and chemical oxygen demand removal of disperse and reactive dyebath solutions by ozonation.
- Author
-
Aksel Eren, Hüseyin, Avinc, Ozan, and Erismis, Burcu
- Subjects
CHEMICAL oxygen demand ,OZONIZATION ,COLOR ,DYES & dyeing ,OXYGEN - Abstract
In this study, the effects of ozonation, ozonation with ultrasonic bath and ozonation with ultrasonic homogeniser processes on colour and chemical oxygen demand removal properties of disperse (CI Disperse Red 60, CI Disperse Blue 337) and reactive (CI Reactive Blue 171 and CI Reactive Blue 19) dyebath solutions with and without dyeing auxiliaries were investigated. Chemical oxygen demand (in mg/l) and colour (in Hazen) measurements of the studied dyebath solutions were determined. The ozonation process caused simultaneous chemical oxygen demand removal during decolorisation. However, the improvement in chemical oxygen demand reduction was less than of that on decolorisation. The application of the combination of ozonation with ultrasonic homogeniser is the most efficient process and creates a great time advantage over the other process types studied (ozonation alone and ozonation with ultrasonic bath) to reach the same colour and levels of chemical oxygen demand removal. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
10. Simultaneous afterclearing and decolorisation by ozonation after disperse dyeing of polyester.
- Author
-
Eren, Hüseyin Aksel
- Subjects
SYNTHETIC fiber dyeing ,OZONIZATION ,COLOR in the textile industries ,COLORFASTNESS (Textiles) ,GAS flow ,DYES & dyeing - Abstract
A set of trials have been conducted to examine the efficiency of ozonation on afterclearing of disperse dyed poly(ethylene terephthalate) fibres. Ozonation was performed in the cooled dyebath after the completion of the dyeing cycle. The ozone concentration used was 12.8 ± 0.3 mg/min at a gas flow rate of 400 ml/min. The results indicate that 3 min ozonation time is appropriate to achieve wash fastness results comparable to conventional reduction clearing. These results were obtained with simultaneous dyebath decolorisation ratios up to 67% and without significant colour yield ( K/S value) losses of the dyed fabric. Ozonation periods exceeding 3 min caused significant colour yield ( K/S value) losses, although dyebath decolorisation ratios increased up to 82% and wash fastness properties further improved. The chemical oxygen demand of the dyeing process decreased up to 62% by the ozonation afterclearing. The advantages of the ozonation afterclearing process are savings in terms of water, energy and time and reduction in environmental load. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
11. Afterclearing by ozonation: a novel approach for disperse dyeing of polyester.
- Author
-
Eren, Hüseyin Aksel
- Subjects
OZONIZATION ,DYES & dyeing ,COLOR in the textile industries ,GAS flow ,CHEMICAL reduction ,CHEMICAL reactions ,FORCE & energy ,SYNTHETIC fibers ,TEXTILES - Abstract
A set of trials has been conducted to examine the efficiency of ozonation afterclearing on poly(ethylene terephthalate) fibres dyed with disperse dyes. The afterclearing process was performed in neutral distilled water at room temperature with 12.8 ± 0.3 mg/min ozone at 400 ml/min ozone gas flow rate. The results indicate that 1 min ozonation time is adequate to achieve wash fastness results comparable with conventional reduction clearing without significant colour yield losses. Ozonation periods greater than 1 min not only caused significant colour yield losses, but also caused a severe decrease of the breaking load of the fabric. The advantages of ozonation afterclearing are: savings in energy and time, as it is performed at room temperature for only 1 min, and decrease of environmental load as it avoids the use of the harsh chemicals used in conventional reduction clearing. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
12. Efficacy and safety of rectal thiopental: Sedation for children undergoing computed tomography and magnetic resonance imaging.
- Author
-
Alp, Güler, İbrahim, Orbak, Karakelleoğlu, Eren, Hüseyin Tan, and Orbak, Zerrin
- Subjects
TOMOGRAPHY ,MAGNETIC resonance imaging ,RECTAL medication ,ANESTHESIA - Abstract
Abstract Purpose: We evaluated the clinical safety, effectiveness, efficiency and potential side effects of rectally administered thiopental in 30 children undergoing computed tomography (CT) and magnetic resonance imaging (MRI). Methods: The doses of thiopental used were 50 mg/kg for infants under 6 months of age, 35 mg/kg for infants between 6 and 12 months of age and 25 mg/kg for older children. After administration of the sedative, oxygen saturation was continuously monitored and vital signs were recorded every 20 min during the imaging procedure and then every 20 min until discharge. Results: Successful sedation and adequate imaging were obtained in 29 of 30 (96.7%) patients. Respiratory depression was not observed in any patient. However, oxygen saturation dropped below 90% transiently (to 88%) in three patients (10.0%) and this was immediately corrected by repositioning the child’s neck to open the upper airway. All successfully sedated patients were asleep within 15 min (mean~SD 7.3~2.7 min) and sedation was sufficient for at least 30 min. Prolonged sedation was observed in two patients. Conclusions: We believe that rectal thiopental is a safe, effective and efficient form of sedation for pediatric imaging. [ABSTRACT FROM AUTHOR]
- Published
- 1999
- Full Text
- View/download PDF
13. A Giant Pedunculated Urothelial Polyp Mimicking Bladder Mass in a Child: A Rare Case.
- Author
-
Kaba, Mehmet, Kaba, Sultan, Kaya, Tacettin Yekta, Eren, Hüseyin, and Pirinççi, Necip
- Subjects
PEDIATRIC radiography ,PEDIATRIC tomography ,COMPUTED tomography ,HEMATURIA in children - Abstract
Ureteral fibroepithelial polyps are rarely seen benign tumors with mesodermal origin. These polyps can involve kidney, pelvis, ureter, bladder, and urethra. The most common symptoms are hematuria and flank pain. The choice of treatment is either endoscopic or surgical resection of polyp by sparing kidney. Here, we presented a pediatric case with giant, fibroepithelial polyp that mimics bladder tumor, originating from middle segment of the ureter. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.