ENHANCEMENT OF LIPID EXTRACTION BY MIXTRURE OF ETHYL ACETATE AND EHANOL FROM MICROALGAE VIA DEEP EUTECTIC SOLVENTS PRETREATMENT

Weidong LU,Zhongming WANG,Ying PAN,Zhenhong Yuan 한국신재생에너지학회 2015 AFORE Vol.2015 No.11

Evaluation of an Immune-privileged Scaffold for In vivo Implantation of Tissue-engineered Trachea

Shu Pan,Fei Sun,Hongcan Shi,Fangbiao Zhang,Xingchen Liu,Weidong Zhang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.5

Forty tracheas were harvested from donor NewZealand rabbits. Thirty of the tracheas were randomlydivided into four treatment groups corresponding to 4, 5, 6,or 7% NaClO4 and one untreated group (n = 6 each group). Scanning electron microscopy distinctly revealed thecilium of epithelial cells in the fresh trachea. The internalsurface of the trachea was rough in the 4% treatment groupand smooth in the 5% treatment group, whereas the matrixwas fractured in the 6% treatment group and highlyfractured in the 7% treatment group. We observed that thenumber of nuclei in the cells of the 4, 5, 6, and 7%treatment groups decreased compared to the cells of theuntreated group (p < 0.05). Although there was a significantdecrease in maximum tensile strength, tensile strain atfracture and the elastic modulus (p < 0.05) with increasingconcentrations of NaClO4, the content of glycosaminoglycans(GAGs) did not significantly decline (p > 0.05) in the 5%treatment group. In addition, histopathological analysisshowed that the fiber component and basement membraneof the matrix in the 5% treatment group were retained afteroptimal decellularization. Despite the preserved cartilage,in vitro immunohistochemical analysis revealed that thematrix did not show the presence of major histocompatibilitycomplex (MHC) antigens. The remaining ten donor tracheas,which were divided into a positive control group and anoptimal decellularized group, were used for allogeneictransplantation. Blood samples were taken regularly, andhistologic examinations were performed at 30 days postimplantation,which showed no significant immune rejection. In conclusion, we surveyed the structural integrity throughmorphological observation and compared the biomechanicaland immunogenic changes in the tracheal matrix under thedifferent treatments. The optimal decellularized trachealmatrix with preserved cartilage, which was acquired via 5%NaClO4 treatment, exhibited structural integrity, antigen cellremoval and immune privilege and would be suitable for useas a tissue-engineered trachea for in vivo transplantation inrabbit models.

Optimization of algal lipid extraction by mixture of ethyl acetate and ethanol via response surface methodology for biodiesel production

Zhong-Ming Wang,Weidong Lu,Md Asraful Alam,Ying Pan,William Junior Nock,Zhen-Hong Yuan 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.9

The effects of extraction time, extraction temperature, solvent to biomass ratio and solvent composition on lipid yield from lyophilized Chlorococcum sp. biomass using a mixture of ethyl acetate and ethanol (EAE), a new proposed solvent, were studied. Subsequently, the process conditions of extraction by EAE were optimized using Box- Behnken design (BBD). The results revealed that the extraction temperature had the greatest effect on lipid extraction efficiency, followed by volume ratio of ethyl acetate to ethanol (EA/E) and extraction time. The largest lipid extraction yield of 15.74% was obtained under the following extraction conditions: 40mL solvents per gram of biomass for 270 min with gentle stirring at 80 oC by EAE with an EA/E of 1.0. Furthermore, palmitic acid, stearic acid, oleic acid, and linoleic acid were the most abundant fatty acids in the lipids extracted, indicating the great potential of the proposed lipid extraction procedure for microalgae-based biodiesel production.

67-fs pulse generation from a mode-locked Tm,Ho:CLNGG laser at 2083 nm

Zhao, Yongguang,Wang, Yicheng,Chen, Weidong,Pan, Zhongben,Wang, Li,Dai, Xiaojun,Yuan, Hualei,Zhang, Yan,Cai, Huaqiang,Bae, Ji Eun,Choi, Sun Young,Rotermund, Fabian,Loiko, Pavel,Serres, Josep Maria,Mat The Optical Society 2019 Optics express Vol.27 No.3

Objective Evaluation of Fabric Wrinkles Based on 2-D Gabor Transform

Kangjun Shi,Jingan Wang,Lei Wang,Ruru Pan,Weidong Gao 한국섬유공학회 2020 Fibers and polymers Vol.21 No.9

In order to establish an objective, stable and efficient wrinkle evaluation system for fabric wrinkle evaluation, amethod based on 2-D Gabor transform was proposed. Among this system, the directions of Gabor filter were determinedaccording to the range of amplitude response. Then a set of Gabor filters were obtained by selecting and optimizing thecentral frequency, the half peak bandwidth and the shape factor of the Gaussian surface. After Gabor transform by such filterbank, the amplitudes of different response spectrums were extracted, constructing a multi-dimensional feature vector. Finally,the feature vectors of the fabric image samples, whose wrinkle degrees were evaluated manually in advance, were extractedand used to train a support vector machine (SVM), which achieved 81.82 % evaluation accuracy on the 345 samples. Thetrained SVM was applied to evaluate the wrinkle degree of the fabric samples acquired in different illumination directions,and verified the stability of the proposed method to illumination environment. Compared with the existing method, theproposed method has higher classification accuracy. The comparison results indicate the Gabor amplitude feature proposedby this research has a high correlation with the fabric wrinkle grades.

Color Prediction for Pre-Colored Cotton Fiber Blends Based on Improved Kubelka-Munk Double-Constant Theory

Ge Zhang,Jian Zhou,Ruru Pan,Lei Wang,Weidong Gao 한국섬유공학회 2021 Fibers and polymers Vol.22 No.2

The accuracy of color prediction results for pre-colored fiber blends is critical in the textile industry. In this paper,we attempt to investigate a feasible method for predicting the color of pre-colored fibers blends. Five pre-colored cottonfibers were divided into two groups, one for achromatic primaries (white and black) and one for chromatic primaries (red,blue, and yellow). Their respective absorption coefficient (K) and scattering coefficient (S) were calculated by the leastsquares method from the prepared fiber blends samples. The color information of the 34 test blending samples including twoprimaryand three-primary was predicted by the improved Kubelka-Munk (K-M) double-constant theory. Comparing withthe measurement results, the minimum and maximum DE00 color differences were 0.215 and 1.890. The variance of colordifference for two-primary samples was 0.128 and for three-primary samples was 0.154, both were smaller than that obtainedby the K-M theory relative value method, the Stearns-Noechel (S-N) model, revised S-N models, and the Friele model. Theresults show that the improved K-M double-constant theory can be used to better predict the color blending effect of precoloredfibers.

Wear Behavior of P/M High Nb Containing γ-TiAl Alloy in Different Environments

Jingwen Qiu,Zhengfan Fu,Bin Liu,Yong Liu,Jianhui Yan,Di Pan,Weidong Zhang 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.6

The wear behavior of Ti–45Al–7Nb–0.3W (at%) alloy prepared by powder metallurgy (P/M) has been investigated using pinon-disk wear tests at the room temperature. The dry sliding wear tests were performed against on a zirconia disk in differentenvironments, viz, argon, hydrogen in nitrogen mixture, air and oxygen. The worn surfaces of Ti–45Al–7Nb–0.3W pins andwear debris were examined by scanning electron microscope, X-ray diffractometer and X-ray photoelectron spectroscopy. It was found that the high Nb containing Ti–45Al–7Nb–0.3W alloy didn’t exhibit better wear resistance in the presence ofoxygen than commercial γ-TiAl (Ti–47Al–2Nb–2Cr–0.2W) alloy. The oxidation on the worn surface and spalling of oxidescaused by the mechanical force during sliding were the main reason for the high wear losses in the air and oxygen. Thezirconia disk underwent a phase transformation caused by the high contact temperature and stress during the sliding tests. The abrasive particles produced in the wear tests largely consisted of the zirconia particles in different environments, exceptin the pure oxygen. The hard zirconia debris was embedded into the friction layer on the worn surfaces of TiAl pins, whichprovided protection against wear to some extent. The main wear mechanisms of Ti–45Al–7Nb–0.3W alloy were abrasivewear of two-body and three-body, some delamination and plastic deformation.

Insect cytokine growth-blocking peptide may regulate density-dependent phase trait of cuticular melanization in the larval armyworm, Mythimna separata

Zhang Yingchao,He Juan,Zhang Yuxia,Li Yue,Yu Yang,Jiang Xingfu,Pan Weidong 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

Growth-blocking peptide (GBP) is a 25 amino acid insect cytokine found in lepidopteran insects that has diverse biological activities such as larval growth regulation, paralysis induction, cell proliferation and stimulation of immune cells. Density-dependent phase polyphenism is a phenomenon of phenotypic plasticity in which the expression of a variety of traits can be affected by local population density. In the present study, the armyworm Mythimna separata larvae with four rearing densities (1 larva/vial, 2 larvae/vial, 4 larvae/vial and 6 larvae/vial) were tested for cuticular melanization and body weight throughout the third-fifth instar, and the functional role of GBP in regulating the changes was investigated. The results indicated that when reared at high densities, the larvae exhibited less body weight and more degree of cuticular melanization than larvae reared at low densities. The gene expression of GBP in armyworm larvae showed an initial rise and then decline trend with increased rearing densities in the third to fifth instar. Compared with control, more degree of cuticular melanization was observed in GBP-injected larvae (500 ng/larva in volume 50 μL) than that in Ringer’s solution-injected counterparts. Furthermore, the gene expression level of dopa decarboxylase and prophenoloxidase increased significantly in GBP-injected fifth instar larvae from 6 h to 12 h after injection, suggesting the role of GBP in modulating density-dependent phase trait of armyworm cuticular melanization.