http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Reza Saghafi (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Marziyeh Ranjbar-Mohammadi,Vida Sa’di,Meysam Moezzi,Reza Saghafi 한국섬유공학회 2022 Fibers and polymers Vol.23 No.6
Antibacterial suture yarns containing antibiotic drugs can play an important role in preventing the infection andholding tissues together to achieve wound closure. In this research, the possibility of production drug loaded nano yarns froma mixture of chitosan/polyvinyl alcohol (PVA/CS) (70:30) and poly(lactic acid) (PLA) was assessed by combiningdual‐electrospinning technique with aligned fibers collection. For this, CS/PVA solution was injected from one syringe andPLA from another one. The effect of weight ratio of PLA-PVA/CS (100:0, 80:20 and 60:40), collector speed (500, 800,1100 rpm) and voltage (10, 15 and 20 kV) on the diameter and morphology of fabricated nanofibers was assessed. Fabricatednanofibers with the length of 70 cm were twisted for manufacturing suture yarns. The results showed that fabrication ofstructure with the finest diameter was possible with the weight ratio of PLA-PVA/CS (60:40), the applied voltage of 15 kV,spinning distance of 17 cm and the rotational speed of about 1100 rpm. The diameter of produced nanofibers in this conditionwas about 290±42 nm. Then, tetracycline hydrochloride (T) loaded PLA-PVA/CS nanofibers (PLA/T-PVA/CS) wereproduced with optimum condition and the drug (5 wt. %) was loaded in PLA solution. FTIR analysis of drug loaded yarnexhibited the most important functional groups of chitosan, PVA, tetracycline hydrochloride and PLA in PLA-PVA/CSstructure. Contact angle data for PLA-PVA/CS and PLA/T-PVA/CS was about 89±3 ° and 30±2 °, respectively. The result ofthe antibacterial test indicated that the PLA/T-PVA/CS nanofibrous yarns were the most suitable sample with the prominentantibacterial activity against both gram-positive bacterium Staphylococcus aureus and gram-negative bacterium Escherichiacoli with inhibition zones of 17.5 and 20 mm, respectively. It seems that the fabricated nanofiber based yarns with suitablemorphological characteristics, hydrophilicity nature, and prevention of the surgical infections without affecting the cellviability can be an excellent structure for utilization as suture yarn.
-
Amir Farasat,Mohsen Vafaie Sefti,Saeid Sadeghnejad,Hamid Reza Saghafi 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.5
Preformed particle gel (PPG) treatment is now one of the most effective remediation techniques for conformance controlling and selective plugging of high-water flow conduits in mature water-flooded oil reservoirs. Recognizing the intrinsic properties of PPGs, e.g., the swelling ratio, in reservoir condition is of prime importance to the optimization of their performance as plugging agents. In this study, the classical and three-level full factorial experimental design methods are joined with laboratory measurements to investigate the swelling ratio dependency of a new class of enhanced PPGs at different brine salinities and reservoir temperatures. To cover severe reservoir conditions, the reservoir temperature from 298 to 418 K and brine salinity from 0 to 225,000 ppm were considered during the laboratory measurements. The results show that the swelling ratio decreases by rising water salinity. Moreover, the swelling ratio rises by increasing reservoir temperature up to 380K and then starts to decrease. The factor screening illustrates that the swelling ratio is more dependent on salinity than the reservoir temperature in low salinity solutions, while is less dependent on salinity in high salinity solutions. In addition, a precise mathematical model was developed to predict the swelling ratio of PPGs in a wide range of salinities and temperatures. The results of this study present a practical insight into the swelling-related behavior of the PPGs at reservoir conditions.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
