Adsorption of Fluoride Ions from Water by SF/PP Nonwoven Fabrics

Zuoze Fan,Yanfei Gao,Xin Ning,Fukui Pan,Jinfa Ming 한국섬유공학회 2019 Fibers and polymers Vol.20 No.4

Silk fibroin/polypropylene (SF/PP) nonwoven fabrics were prepared via electrospinning method. The compositematerials combine the advantage of nanofibers with the high specific surface area and the strong affinity toward fluoride. SF/PP nonwoven fabrics were characterized, and the adsorption of fluoride was investigated. The results showed the diameter ofSF nanofibers increased from 950±37 nm to 2400±50 nm in nonwoven fabrics with the increase of SF concentration from5.0 wt% to 10 wt%. Before fluoride adsorption, no crystal particles were deposited on the surface of SF/PP nanofibers. Afteradsorption 5 min, only several white crystals were deposited. Within the increase of adsorption times from 10 min to 60 min,many larger crystals were grown. Fluoride ions were confirmed in crystals by EDS. From adsorption rate curve, the rate offluoride removal was rapid initially and slowed down gradually until it attained equilibrium. At the same time, a largefraction of fluoride ions was removed within 20 min of contact times in all the experimental various studied. Therefore, thisnonwoven fabric has a great potential as a novel adsorbent material for the fluoride removal from drinking water.

Sparsity maximization nonlinear blind deconvolution and its application in identification of satellite microvibration sources

Teng Gong,ZhouSuo Zhang,Xin Luo,Jianbin Cao,Yanfei Guo 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.1

In this study, sparsity maximization nonlinear blind deconvolution (NBD) is proposed to identify the vibration sources of satellite systems from mixed vibration signals. The proposed algorithm decomposes NBD into two independent stages, namely, nonlinear compensation and blind deconvolution. Since nonlinear distortion weakens the sparsity of the observed signals, sparsity maximization is introduced to the nonlinear compensation stage. In the blind deconvolution stage, the blind deconvolution algorithm with reference is used to separate the source signals. The proposed algorithm can improve the accuracy of source signal extraction from nonlinear mixed signals of complex mechanical systems. The effectiveness of the proposed method is verified through simulations. An experimental system of aluminum cabin structure is built based on the satellite’s cabin structure. Results show that the proposed algorithm can successfully realize the identification of source signals.

Genotoxicity and subchronic toxicological study of a novel ginsenoside derivative 25-OCH₃-PPD in beagle dogs

Li, Wei,Zhang, Xiangrong,Ding, Meng,Xin, Yanfei,Xuan, Yaoxian,Zhao, Yuqing The Korean Society of Ginseng 2019 Journal of Ginseng Research Vol.43 No.4

Background: Ginsenosides have been widely used clinically for many years and were regarded as very safe. However, a few researches on the toxicities of these kinds of agents showed that some ginsenosides may have side-effect on the rats or dogs. So it is extremely necessary to further clarify the potential toxicity of ginsenosides. This study was carried out to investigate long-term toxicity and genotoxicity of 25-methoxydammarane-3, 12, 20-triol ($25-OCH_3-PPD$), a new derivative of ginsenoside, in beagle dogs. Methods: Twenty-four beagle dogs were divided randomly into four treatment groups and repeatedly orally administered with $25-OCH_3-PPD$ capsule at 60, 120, and 240 mg/kg/day for 91 consecutive days. Ames, micronucleus, and chromosomal aberration tests were established to analyze the possible genotoxicity of $25-OCH_3-PPD$. Results: There was no $25-OCH_3-PPD$einduced systemic toxicity in beagle dogs at any doses. The level of $25-OCH_3-PPD$ at which no adverse effects were observed was found to be 240 mg/kg/day. The result of Ames test showed that there was no significant increase in the number of revertant colonies of $25-OCH_3-PPD$ administrated groups compared to the vehicle control group. There were also no significant differences between $25-OCH_3-PPD$ administrated groups at all dose levels and negative group in the micronucleus test and chromosomal aberration assay. Conclusion: The highest dose level of $25-OCH_3-PPD$ at which no adverse effects were observed was found to be 240 mg/kg per day, and it is not a genotoxic agent either in somatic cells or germs cells. $25-OCH_3-PPD$ is an extremely safe candidate compound for antitumor treatment.

Genotoxicity and subchronic toxicological study of a novel ginsenoside derivative 25-OCH₃-PPD in beagle dogs

Wei Li,Xiangrong Zhang,Meng Ding,Yanfei Xin,Yaoxian Xuan,Yuqing Zhao 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.4

Background: Ginsenosides have been widely used clinically for many years and were regarded as very safe. However, a few researches on the toxicities of these kinds of agents showed that some ginsenosides may have side-effect on the rats or dogs. So it is extremely necessary to further clarify the potential toxicity of ginsenosides. This study was carried out to investigate long-term toxicity and genotoxicity of 25-methoxydammarane-3, 12, 20-triol (25-OCH₃-PPD), a new derivative of ginsenoside, in beagle dogs. Methods: Twenty-four beagle dogs were divided randomly into four treatment groups and repeatedly orally administered with 25-OCH₃-PPD capsule at 60, 120, and 240 mg/kg/day for 91 consecutive days. Ames, micronucleus, and chromosomal aberration tests were established to analyze the possible genotoxicity of 25-OCH₃-PPD. Results: There was no 25-OCH₃-PPD-induced systemic toxicity in beagle dogs at any doses. The level of 25-OCH₃-PPD at which no adverse effects were observed was found to be 240 mg/kg/day. The result of Ames test showed that there was no significant increase in the number of revertant colonies of 25-OCH₃- PPD administrated groups compared to the vehicle control group. There were also no significant differences between 25-OCH₃-PPD administrated groups at all dose levels and negative group in the micronucleus test and chromosomal aberration assay. Conclusion: The highest dose level of 25-OCH₃-PPD at which no adverse effects were observed was found to be 240 mg/kg per day, and it is not a genotoxic agent either in somatic cells or germs cells. 25-OCH₃-PPD is an extremely safe candidate compound for antitumor treatment.

Efficient Expression of Glucagon-like Peptide-1 Analogue with Human Serum Albumin Fusion Protein in Pichia pastoris Using the Glyceraldehyde-3-phosphate Dehydrogenase Promoter

Kai Qian,XiaoHai Gong,Bo Guan,SuPing Wu,JingJing Zhang,Jing Qian,YanFei Cai,Yun Chen,ZuoYing Duan,Xin Ma,HuaZhong Li,Jian Jin 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.4

Glucagon-like peptide-1 (GLP-1) was a potential therapeutic drug for type II diabetes, mainly because of the stimulatory effect on insulin secretion under condition of high blood glucose. We used PCR to obtain a recombination gene, GGH, in which two GLP-1 (GLP-1A2G) mutants were connected in series and then fused to the N terminal of human serum albumin. The fusion gene was inserted into pGAPZaA plasmid with Saccharomyces cerevisiae α- factor secretion signal sequence, and was expressed by the glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter. The engineered strain was constructed by integrating the recombinant plasmid pGAPZαA/GGH into the genome of Pichia pastoris GS115. Genome PCR and western blot showed that the recombinant P. pastoris successfully expressed the fusion protein GGH. The yield of GGH reached 78 mg/L after 72 h fermentation in a flask, using glucose as the optimal carbon source. Fed-batch fermentation was investigated in a 5 L bioreactor, and the expression level of GGH reached 246 mg/L in 52 h. The fusion protein GGH was purified in four steps, and the final purity was 96.1%. The in vitro bioactivity of GGH was the same as that expressed in P. pastoris by the AOX1 promoter. This study described an efficient way to express GGH fusion protein in P. pastoris using GAP promoter, fermentation was easier to control without carbon source change and fermentation time was 20 h less than AOX1 promotercontrolled GGH fermentation.