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 : Yingchun Guo (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
Yingchun Guo,Sheng Chen,Lingqia Su,Jing Wu,Jian Chen 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.6
Polyamidase was able to hydrolyze the amidebond of insoluble polymer. In the present study, apolyamidase from Nocardia farcinica CGMCCC4.1166was cloned and expressed in E. coli BL21(DE3). Therecombinant polyamidase was purified to homogeneity,through a combination of chromatography of anion exchange,and hydrophobic interaction. The purified enzyme wascharacterized in detail. The optimum temperature of theenzyme was 50°C, and it was stable below 40°C. Theenzyme had an optimum pH of 8.0, with pH stabilitybetween pH 7.0 and 9.0. The enzyme does not need metalion as cofactor. In addition, when the enzyme was utilizedto hydrolyze polyamide, the monomeric product of adipicacid was verified by HPLC analysis; as well, the wettabilityand dyeability of polyamide fabric after enzyme treatmentwere significantly improved, which differed from those ofits inactive S173A mutant, and the amidase from Rhodococcuspyridinivorans. Furthermore, the structural featuresnear the active site of polyamidase, different from otheramidases, were explored.
-
Image saliency detection based on geodesic‐like and boundary contrast maps
Yingchun Guo,Yi Liu,Runxin Ma 한국전자통신연구원 2019 ETRI Journal Vol.41 No.6
Image saliency detection is the basis of perceptual image processing, which is significant to subsequent image processing methods. Most saliency detection methods can detect only a single object with a high‐contrast background, but they have no effect on the extraction of a salient object from images with complex low‐contrast backgrounds. With the prior knowledge, this paper proposes a method for detecting salient objects by combining the boundary contrast map and the geodesics‐like maps. This method can highlight the foreground uniformly and extract the salient objects efficiently in images with low‐contrast backgrounds. The classical receiver operating characteristics (ROC) curve, which compares the salient map with the ground truth map, does not reflect the human perception. An ROC curve with distance (distance receiver operating characteristic, DROC) is proposed in this paper, which takes the ROC curve closer to the human subjective perception. Experiments on three benchmark datasets and three low‐contrast image datasets, with four evaluation methods including DROC, show that on comparing the eight state‐of‐the‐art approaches, the proposed approach performs well.
-
Yanli Liu,Yan Xia,Pan Guo,Guiping Wang,Zhenguo Shen,Yingchun Xu,Yahua Chen 한국원예학회 2013 Horticulture, Environment, and Biotechnology Vol.54 No.4
The effects of environmental factors on the paeonol accumulation in cortex moutan of herbal Paeonia suffruticosa cv. Fengdan were investigated. Cortex moutan of ‘Fengdan’ and the corresponding soil samples were collected from Tongling (Anhui Province, China). A pot experiment was also conducted to investigate the responses of plant growth and paeonol concentrations to copper (Cu) supply. The paeonol and Cu concentrations in cortex moutan samples, the basic soil properties and soil’s bacterial diversity were analyzed. The results showed that moderate levels of Cu in the soil enhanced the paeonol concentration in the cortex moutan. Moreover, the paeonol concentration was related significantly to soil bacterial diversity. The results of the pot experiment showed that increasing Cu supply from 63 to 263 mg·kg-1 did not produce any significant effect on the dry weight of ‘Fengdan’ cortex moutan,duramen, and total plant. Increasing Cu supply significantly increased the concentrations of paeonol in cortex moutan and duramen; but at 263 mg·kg-1 Cu there was a slight decline in their concentrations than those obtained at 156mg·kg-1 Cu. In all treatments, the concentrations of paeonol were much higher in the cortex moutan than those in the duramen. Due to its ecological benefits, ‘Fengdan’ can be planted in soil contaminated with moderate Cu.
-
Xue Bai,Yinghui Zhao,Zhenhu Song,Hui Chen,Sihang Zhang,Yonghui Luo,YingChun Gu,Shijian Tu,Guo Yao,Sheng Chen 한국섬유공학회 2022 Fibers and polymers Vol.23 No.3
The preparation of polymer nanocomposites combined with high strength, toughness, and high transparencyremains a challenge. Aramid fibers are often used as fiber-reinforced materials for their superior mechanical and thermalproperties, but the weak interfacial force between aramid fibers and matrix polymer limits the application in compositematerials. In this work, aramid nanofibers were prepared by a two-step process, which included deprotonation and acidhydrothermal treatment to obtain better dispersions in general solvents. The hydrothermal aramid nanofibers (HANFs) wereused as reinforcing materials and blended with polyacrylonitrile (PAN) to prepare polyacrylonitrile/aramid nanofibers (PAN/HANFs) composite films with different mass fractions of HANFs. The morphologies of HANFs and the thermal, optical, andmechanical properties of composite films were investigated. Interestingly, when the mass fraction of aramid nanofibers wasless than 1.0 %, the composite films were synchronously strengthened and toughened. When the mass fraction of HANFswas 0.5 %, the tensile strength and toughness of the PAN/HANFs composite film reached 62.04 MPa and 22.56 MJ/m3,which were 74.23 % and 162.31 % higher than the pure PAN film, respectively. Besides, its average transmittance in thevisible light region remained 76.34 %. This work may offer a novel and facile strategy for high transparent reinforcedpolymer composites, which have potential applications in high strength fiber or optical film.
-
Lili Zhang,Lanwei Zhang,Huaxi Yi,Ming Du,Yingchun Zhang,Xue Han,Zhen Feng,Jingyan Li,Yuehua Jiao,Yanhe Zhang,Chunfeng Guo 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.7
Stress-mediated bioprocess is a strategy designed to enhance biological target productivity. In this study,an attempt was made to enhance transglutaminase (TGase) production by Streptomyces mobaraensis by using different stress conditions including heat shock, alcohols and salt stress. Results showed that the effects of stress on TGase production depended on the type applied. For heat shock, TGase production (1.32 U/ml) was recorded maximum in the culture treated at 48 h post inoculation in water bath at 60 oC for 1 min. For alcohols treatment, the maximum activity of TGase (1.77 and 1.75 U/ml) was obtained when 3% methanol was added into the medium at 0 or 24 h of fermentation. However, a 3.5-fold increased production of TGase (3.8 U/ml) was observed in the medium supplemented with 0.2mol/l MgCl2 compared with the basic medium at the beginning of fermentation. In conclusion, TGase production from S. mobaraensis was improved by heat shock, methanol and salt stress treatments, MgCl2 stress was the most effective.
ScienceON연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
