Analysis of MHD micro-mixers with differential pumping capabilities for two different miscible fluids

Xiao, Xuejiao,Li, Tiantian,Kim, Chang Nyung Elsevier 2018 Chemical engineering research & design Vol.139 No.-

<P><B>Abstract</B></P> <P>In this study, newly devised is a magneto-hydrodynamic (MHD) micro-mixer capable of differential pumping of two different miscible fluids, and numerically investigated are the mixing performance and the mass flow rates of the two fluids. By artfully applying different potentials to different electrode pairs, Lorentz-force with different sizes can be created, driving the liquids in a desired direction for pumping, and inducing fluid circulation at a cross-section for mixing. The results show that the micro-mixer proposed in this study can achieve high mixing performance for electrolytes, together with differential pumping capabilities for the two different miscible fluids. The effect of the total difference in potential applied to the electrodes in pumping section on the mixing performance is numerically analyzed. Also, rectangular and H-shaped cross-sections for pumping section have been examined to explore the geometrical effect on the differential pumping capability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Magnetohydrodynamics can provide a convenient way for pumping and mixing. </LI> <LI> Numerical method based on CFD is used to analyze MHD flows. </LI> <LI> MHD micro-mixer with differential pumping capabilities are investigated. </LI> <LI> The micro-mixer proposed in this study can achieve high mixing performance. </LI> <LI> The geometrical effect on the differential pumping capability is explored. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Role of soy lecithin combined with soy isoflavone on cerebral blood flow in rats of cognitive impairment and the primary screening of its optimum combination

Li Hongrui,Wang Xianyun,Li Xiaoying,Zhou Xueyang,Wang Xuan,Li Tiantian,Xiao Rong,Xi Yuandi 한국영양학회 2023 Nutrition Research and Practice Vol.17 No.2

BACKGROUND/OBJECTIVES: Soy isoflavone (SIF) and soy lecithin (SL) have beneficial effects on many chronic diseases, including neurodegenerative diseases. Regretfully, there is little evidence to show the combined effects of these soy extractives on the impairment of cognition and abnormal cerebral blood flow (CBF). This study examined the optimal combination dose of SIF + SL to provide evidence for improving CBF and protecting cerebrovascular endothelial cells. MATERIALS/METHODS: In vivo study, SIF50 + SL40, SIF50 + SL80 and SIF50 + SL160 groups were obtained. Morris water maze, laser speckle contrast imaging (LSCI), and hematoxylineosin staining were used to detect learning and memory impairment, CBF, and damage to the cerebrovascular tissue in rat. The 8-hydroxy-2′-deoxyguanosine (8-OHdG) and the oxidized glutathione (GSSG) were detected. The anti-oxidative damage index of superoxide dismutase (SOD) and glutathione (GSH) in the serum of an animal model was also tested. In vitro study, an immortalized mouse brain endothelial cell line (bEND.3 cells) was used to confirm the cerebrovascular endothelial cell protection of SIF + SL. In this study, 50 μM of Gen were used, while the 25, 50, or 100 μM of SL for different incubation times were selected first. The intracellular levels of 8-OHdG, SOD, GSH, and GSSG were also detected in the cells. RESULTS: In vivo study, SIF + SL could increase the target crossing times significantly and shorten the total swimming distance of rats. The CBF in the rats of the SIF50 + SL40 group and SIF50 + SL160 group was enhanced. Pathological changes, such as attenuation of the endothelium in cerebral vessels were much less in the SIF50 + SL40 group and SIF50 + SL160 group. The 8-OHdG was reduced in the SIF50 + SL40 group. The GSSG showed a significant decrease in all SIF + SL pretreatment groups, but the GSH showed an opposite result. SOD was upregulated by SIF + SL pretreatment. Different combinations of Genistein (Gen)+SL, the secondary proof of health benefits found in vivo study, showed they have effective antioxidation and less side reaction on protecting cerebrovascular endothelial cell. SIF50 + SL40 in rats experiment and Gen50 + SL25 in cell test were the optimum joint doses on alleviating cognitive impairment and regulating CBF through protecting cerebrovascular tissue by its antioxidant activity. CONCLUSIONS: SIF+SL could significantly prevent cognitive defect induced by β-Amyloid through regulating CBF. This kind of effect might be attributed to its antioxidant activity on protecting cerebral vessels.

A (n, t, n) Verifiable Multi-secret Sharing Scheme with Secure Secret Reconstruction

Li Meng,Qu Shaoyun,Xun Tiantian,Yu Jia 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.1

Characteristics of the gut microbiota colonization, inflammatory profile, and plasma metabolome in intrauterine growth restricted piglets during the first 12 hours after birth

Shimeng Huang,Na Li,Cong Liu,Tiantian Li,Wei Wang,Lili Jiang,Zhen Li,Dandan Han,Shiyu Tao,Junjun Wang 한국미생물학회 2019 The journal of microbiology Vol.57 No.9

Intrauterine growth restriction (IUGR) predisposes newborns to inflammatory and metabolic disturbance. Disequilibrium of gut microbiota in early life has been implicated in the incidence of inflammation and metabolic diseases in adulthood. This study aimed to investigate the difference in gut microbiota colonization, cytokines and plasma metabolome between IUGR and normal birth weight (NBW) piglets in early life. At birth, reduced (P < 0.05) body, jejunum, and ileum weights, as well as decreased (P < 0.05) small intestinal villi and increased (P < 0.05) ileal crypt depth were observed in IUGR piglets compared with their NBW counterparts. Imbalanced inflammatory and plasma metabolome profile was observed in IUGR piglets. Furthermore, altered metabolites were mainly involved in fatty acid metabolism and inflammatory response. At 12 h after birth and after suckling colostrum, reduced (P < 0.05) postnatal growth and the small intestinal maturation retardation (P < 0.05) continued in IUGR piglets in comparison with those in NBW littermates. Besides, the gut microbiota structure was significantly altered by IUGR. Importantly, the disruption of the inflammatory profile and metabolic status mainly involved the pro-inflammatory cytokines (IL-1β and IFN-γ) and amino acid metabolism. Moreover, spearman correlation analysis showed that the increased abundance of Escherichia-Shigella and decreased abundance of Clostridium_sensu_stricto_1 in IUGR piglets was closely associated with the alterations of slaughter weight, intestinal morphology, inflammatory cytokines, and plasma metabolites. Collectively, IUGR significantly impairs small intestine structure, modifies gut microbiota colonization, and disturbs inflammatory and metabolic profiles during the first 12 h after birth. The unbalanced gut microbiota mediated by IUGR contributes to the development of inflammation and metabolic diseases.

A new separation method for phenolic compounds from low-temperature coal tar with urea by complex formation

Tiantian Jiao,Chunshan Li,Maoming Gong,Xulei Zhuang,Suojiang Zhang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-

A new reaction agent (urea) was used to efficiently separate the phenol and cresols from lowtemperaturecoal tar (model oil) through complexing. The effects of contact time, reaction temperature,and initial concentration were investigated. The phenols content of the upper layer was analyzed byusing gas chromatography. The separation mechanism was determined by analyzing the chemical bondof the complex for urea and m-cresol using Fourier transform infrared spectrometer. Finally, urea can berecovered through reaction with diethyl ether, and the phenols removal efficiencies can remain constantafter three cycles.

The mechanism of photocurrent enhancement of ZnO ultraviolet photodetector by reduced graphene oxide

Tiantian Yang,Bin Sun,Lei Ni,Xing Wei,Tingting Guo,Zhemin Shi,Fei Han,Li Duan 한국물리학회 2018 Current Applied Physics Vol.18 No.8

An ultraviolet (UV) photodetector based on ZnO-reduced graphene oxide (ZnO-rGO) composites have been successfully fabricated. A pure ZnO photodetector was also fabricated by similar method. In comparison with the pure ZnO UV photodetector, the ZnO-rGO photodetector exhibits a much larger photocurrent and a better lightto- dark-current-ratio. The mechanism of photocurrent enhancement was investigated using I-V characteristics, photoluminescence (PL) spectra, transmittance spectra and time-dependent photocurrent analysis. Results show that the photocurrent enhancement of the ultraviolet photodetector is due to the improvement of the carrier lifetime, because the carrier recombination of ZnO were reduced by rGO. It provides a potential way to fabricate high-response UV photodetectors.

Dynamic colonization of gut microbiota and its influencing factors among the breast-feeding infants during the first two years of life

Li Ping,Chang Xuelian,Chen Xiaoyu,Tang Tiantian,Liu Yajing,Shang Yu,Qi Kemin 한국미생물학회 2022 The journal of microbiology Vol.60 No.8

The maturation of infant gut microbiota has lifelong implications on health, which has been proposed as the major events during the first year of life. However, little is known about their dynamic colonization and influencing elements among the first two-year infancy as well as into the adulthood. So based on the 16S rRNA sequencing data among 30 healthy breast-feeding mother-infant pairs with normal ranges of growth and development indicators from birth to two years old, the dynamic colonization of gut microbiota and its influencing factors were discussed using this birth cohort. Among these, we identified that the diversity of gut microbiota was significantly increased from six-month to two-year subgroups. The significantly dynamic trends of gut microbiota at the phylum (genus) level were that the percents of Firmicutes (Faecalibacterium, Blautia, Enterococcus, Subdoligranulum, Agathobacter, unidentified_Erysipelotrichaceae, Staphylococcus, unidentified_Ruminococcaceae, and Fusicatenibacter), Bacteroidetes and Verrucomicrobia were increased, while Actinobacteria (Bifidobacterium) and Proteobacteria (unidentified- Enterobacteriaceae and Klebsiella) were decreased with the increased ages from six months to two years old, which might simultaneously modulate the host pathways, such as the higher percents of chemoheterotrophy and fermentation, and lower percentages of nitrate_reduction, aerobic_chemoheterotrophy and so on. Furthermore, there were significant associations between maternal (milk microbiota, pre-pregnancy BMI, BMI increment during the pregnancy)/infant characteristics (BMI at birth and BMI gain), and the compositions of gut microbiota. However, no differences of gut microbiota were shown between the different sex and productive mode subgroups. Overall, the colonization of gut microbiota is significantly matured into the adulthood with the increased ages to two-years old and regulated by the above maternal/infant characteristics, which will provide a new direction for the host-gut microbiota interplay during the first two years of life.

Dual-Encoded Features from Both Spatial and Curvelet Domains for Image Smoke Recognition

( Feiniu Yuan ),( Tiantian Tang ),( Xue Xia ),( Jinting Shi ),( Shuying Li ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.4

Visual smoke recognition is a challenging task due to large variations in shape, texture and color of smoke. To improve performance, we propose a novel smoke recognition method by combining dual-encoded features that are extracted from both spatial and Curvelet domains. A Curvelet transform is used to filter an image to generate fifty sub-images of Curvelet coefficients. Then we extract Local Binary Pattern (LBP) maps from these coefficient maps and aggregate histograms of these LBP maps to produce a histogram map. Afterwards, we encode the histogram map again to generate Dual-encoded Local Binary Patterns (Dual-LBP). Histograms of Dual-LBPs from Curvelet domain and Completed Local Binary Patterns (CLBP) from spatial domain are concatenated to form the feature for smoke recognition. Finally, we adopt Gaussian Kernel Optimization (GKO) algorithm to search the optimal kernel parameters of Support Vector Machine (SVM) for further improvement of classification accuracy. Experimental results demonstrate that our method can extract effective and reasonable features of smoke images, and achieve good classification accuracy.

Automatic identification and analysis of multi-object cattle rumination based on computer vision

Yueming Wang,Tiantian Chen,Baoshan Li,Qi Li 한국축산학회 2023 한국축산학회지 Vol.65 No.3

Rumination in cattle is closely related to their health, which makes the automatic monitoring of rumination an important part of smart pasture operations. However, manual monitoring of cattle rumination is laborious and wearable sensors are often harmful to animals. Thus, we propose a computer vision-based method to automatically identify multi-object cattle rumination, and to calculate the rumination time and number of chews for each cow. The heads of the cattle in the video were initially tracked with a multi-object tracking algorithm, which combined the You Only Look Once (YOLO) algorithm with the kernelized correlation filter (KCF). Images of the head of each cow were saved at a fixed size, and numbered. Then, a rumination recognition algorithm was constructed with parameters obtained using the frame difference method, and rumination time and number of chews were calculated. The rumination recognition algorithm was used to analyze the head image of each cow to automatically detect multi-object cattle rumination. To verify the feasibility of this method, the algorithm was tested on multi-object cattle rumination videos, and the results were compared with the results produced by human observation. The experimental results showed that the average error in rumination time was 5.902% and the average error in the number of chews was 8.126%. The rumination identification and calculation of rumination information only need to be performed by computers automatically with no manual intervention. It could provide a new contactless rumination identification method for multi-cattle, which provided technical support for smart pasture.

Monitoring polarization and dielectric relaxation behaviors of BaTiO3/ PC composite films via transmittance measurement

Haifa Zhai,Jinfeng Wang,Tiantian Zhang,Min Su Cho,Hongying Luo,Haiqin Li,In Man Kang,Hairui Liu,Jian Su 한국물리학회 2016 Current Applied Physics Vol.16 No.7

BaTiO3/polycarbonate (BT/PC) composite films with different concentration of BaTiO3 ferroelectric nanocrystals are prepared by a spin coating method. The polarization and dielectric relaxation behaviors of BT/PC composite films are characterized by the introduction of orientational order parameter (f) through in-situ transmission spectrum measurement. It's found that 15%BT/PC composite film has the largest orientation change with the f value of 10.5% and slow dielectric relaxation, almost 10% decay of f after 24 h. The optical band-gap of 15%BT/PC composite film decreases after poling indicates that the orientation of BaTiO3 ferroelectric nanocrystals aligns due to the effect of polarization, from 3.8 eV to 3.67 eV. From the XRD results, we consider that the preferential alignment orientation of BaTiO3 ferroelectric nanocrystals after poling is [001]. This suggests that in-situ transmittance measurement is a simple and effective way to evaluate the polarization and dielectric relaxation behaviors of ferroelectric nanocrystals/polymer systems.