Fabrication of dual-coated graphene oxide nanosheets by polypyrrole and poly(ionic liquid) and their enhanced electrorheological responses

Chen, Panpan,Cheng, Qianqian,Wang, Li-Min,Liu, Ying Dan,Choi, Hyoung Jin Elsevier 2019 Journal of industrial and engineering chemistry Vol.69 No.-

<P><B>Abstract</B></P> <P>A two-dimensional composite material, poly(ionic liquid)-modified graphene oxide/polypyrrole (GO/PPy/PIL) multilayered nanosheets, was fabricated and applied as a new electrorheological (ER) material. The morphological differences between the single- and dual-coated nanosheets were confirmed using scanning electron microscopy and transmission electron microscopy. Rheological properties measured using a rotational rheometer indicated that the GO/PPy/PIL composite nanosheets exhibited relatively high ER effect under a certain electric field strength than the GO/PPy nanosheets because of the universal PIL second coating. The dual-coated nanosheets also showed a higher applicable electric field strength due to the semiconductive properties of the thick PIL layer.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dual-coated composite GO/PPy/PIL nanosheets were fabricated. </LI> <LI> The PIL second coating significantly enhanced the ER effect of the nanosheets. </LI> <LI> GO/PPy/PIL exhibited higher available electric field strength than GO/PPy. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Exploring COVID-19 in mainland China during the lockdown of Wuhan via functional data analysis

Li, Xing,Zhang, Panpan,Feng, Qunqiang The Korean Statistical Society 2022 Communications for statistical applications and me Vol.29 No.1

In this paper, we analyze the time series data of the case and death counts of COVID-19 that broke out in China in December, 2019. The study period is during the lockdown of Wuhan. We exploit functional data analysis methods to analyze the collected time series data. The analysis is divided into three parts. First, the functional principal component analysis is conducted to investigate the modes of variation. Second, we carry out the functional canonical correlation analysis to explore the relationship between confirmed and death cases. Finally, we utilize a clustering method based on the Expectation-Maximization (EM) algorithm to run the cluster analysis on the counts of confirmed cases, where the number of clusters is determined via a cross-validation approach. Besides, we compare the clustering results with some migration data available to the public.

Enhancement of Gas Permeability for CH4/N2 Separation Membranes by Blending SBS to Pebax Polymers

Panpan Guan,Jujie Luo,Wei Li,Ziqin Si 한국고분자학회 2017 Macromolecular Research Vol.25 No.10

Three poly(ether-b-amide) (Pebax) membranes with different polyamide (PA) contents were prepared to study CH4/N2 gas separation property. The increase in CH4 and N2 gas permeability was observed with the lowering of PA content. It was attributed to the decreased fraction of impermeable crystalline PA regions and the decrease in the crystallinity of the semi-crystalline PA phase of Pebax membranes. This result is consistent with the previous reports on other gases for Pebax membranes. To lower the crystallinity and higher the CH4 permeability, 10wt% poly(styrene-b-butadiene-b-styrene) (SBS) block copolymer was blended with Pebax. For single gas permeation test, we demonstrated that CH4 permeability of the Pebax/SBS blend membrane is 60% higher than that of Pebax, reaching 106 Barrer at 55 °C. In CH4 and N2 mixed gas permeation test, up to 26 vol% of CH4 could be obtained from passing 10 vol% CH4 of CH4/N2 mixed gas through the Pebax/SBS membranes, demonstrating that Pebax based membranes could potentially be applied to the enrichment of CH4 for the coal-bed methane (CBM).

Fabrication of dual-coated graphene oxide nanosheets by polypyrrole and poly(ionic liquid) and their enhanced electrorheological responses

Panpan Chen,Qianqian Cheng,Li-Min Wang,Ying Dan Liu,최형진 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.69 No.-

A two-dimensional composite material, poly(ionic liquid)-modified graphene oxide/polypyrrole (GO/PPy/PIL) multilayered nanosheets, was fabricated and applied as a new electrorheological (ER) material. The morphological differences between the single- and dual-coated nanosheets were confirmed using scanning electron microscopy and transmission electron microscopy. Rheological properties measured using a rotational rheometer indicated that the GO/PPy/PIL composite nanosheets exhibited relatively high ER effect under a certain electric field strength than the GO/PPy nanosheets because of the universal PIL second coating. The dual-coated nanosheets also showed a higher applicable electric field strength due to the semiconductive properties of the thick PIL layer.

Apoptosis and autophagy of muscle cell during pork postmortem aging

Li Chunmei,Yin Xialian,Xue Panpan,Wang Feng,Song Ruilong,Song Qi,Su Jiamin,Zhang Haifeng 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.2

Objective: Pork is an important source of animal protein in many countries. Subtle physiochemical changes occur during pork postmortem aging. The changes of apoptosis and autophagy in pork at 6 h to 72 h after slaughter were studied to provide evidence for pork quality. Methods: In this article, morphological changes of postmortem pork was observed through Hematoxylin-eosin staining, apoptotic nuclei were observed by TdT-mediated dUTP nick end labeling assay, protein related to apoptosis and autophagy expressions were tested by western blot and LC3 level were expressed according to immunofluorescence assay. Results: In this study, we found the occurrence of apoptosis in postmortem pork, and the process was characterized by nucleus condensation and fragmentation, formation of apoptotic bodies, increase in apoptosis-related Bax/Bcl-2 levels, and activation of caspases. Autophagy reached its peak between 24 and 48 h after slaughter, accompanied by the formation of autophagosomes on the cell membrane and expression of autophagy-related proteins beclin-1, P62, LC3-I, LC3-II, and ATG5. Conclusion: Obvious apoptosis was observed at 12 h and autophagy reached its peak at 48 h. The present work provides the evidence for the occurrence of apoptosis and autophagy during postmortem aging of pork. In conclusion, the apoptosis and autophagy of muscle cells discovered in this study have important implications for pork in the meat industry.

Potential rocky desertification simulation for the karst plateau area using CA-Markov model

Panpan Zhang,Yuanman Hu,Duning Xiao,Xiuzhen Li,Jie Yin 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

It has been recognized that karst rocky desertification is one of the most serious geo-ecological problem in Southwestern China. Understanding the development trend of karst rocky desertification is of fundamental importance in rocky desertification management and control. More attention should be paid to karst areas with potential rocky desertification. In this paper, ARFGIS software was used to discribe the historical and current situation of potential rocky desertification spatial pattern in the middle and lower reaches of houzhai stream, a typical karst plateau area. Remote sensing images from the study area, Remote sensing images from the study area, collected in 1987,1955 and 2004 were used for spatial pattern simulation of potential rocky desertification subdivided into six types: none, extreme slightly, slightly, moderately, severely and extreme severely. The result showed that the potential rocky desertification landscape distributed unevenly; a little more than half of the are showed gradual rocky desertification trend and about 60% of those regions had emarkable rocky desertification trend; Slightly potential rocky desertification was increasing all the time, while the other five types of potential rocky desertification had different change tendencies during different states. Then based on CA-Markov model, the potential rocky desertification spatial pattern was predicted. Verification with investigation based on map in 2004 indicated that 87.2% of the simulation was consistant with real data. therefore the model is robust in prediction potential rocky desertification spatial pattern in this study area.

Analysis of Global Sagittal Postural Patterns in Asymptomatic Chinese Adults

Panpan Hu,Miao Yu,Zhuoran Sun,Weishi Li,Liang Jiang,Feng Wei,Xiaoguang Liu,Zhongqiang Chen,Zhongjun Liu 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.2

Study Design: A prospective imaging study. Purpose: To characterize the distribution of the global sagittal postural patterns in asymptomatic Chinese adults using Roussouly classification. Overview of Literature: The norms of sagittal parameters in asymptomatic Chinese population have been previously described, but no report described their global sagittal postural patterns as characterized by Roussouly classification. Methods: A cohort of 272 asymptomatic Chinese adults was recruited. Data was assimilated by reviewing the films for each subject. Sagittal parameters were measured and sagittal postural patterns were then determined according to Roussouly classification. The pattern distributions were compared across genders within the study cohort. We also compared the data across different ethnicities from our study and a previous study to further characterize Chinese sagittal postures. Results: The cohort included 161 males and 111 females, with mean age of 23.2±4.4 years. The average descriptive results were as below: pelvic incidence (PI) 46.4°±9.6°, thoracic kyphosis (TK) 24.2°±9.0°, lumbar lordosis (LL) 50.6°±10.6°, sacral slope (SS) 37.2°±7.6°, pelvic tilt (PT) 9.4°±6.8°, spinosacral angle (SSA) 131.1°±7.5° and sagittal vertical axis (SVA) 17.24±32.36 mm. Despite a significant difference between two genders in LL, PI, SSA, and SVA, no difference was found in the distribution of Roussouly types among them. 47.8% of our cohort belonged to Roussouly type 3, while type 1, 2 and 4 comprised 23.2%, 14.0% and 15.1% of the subjects, respectively. Roussouly classification was capable of categorizing sagittal parameters except for the PT. This study also found that 4.4% of the recruited subjects belonged to the C7-anterior subgroup. Conclusions: From a characterization of the sagittal postural patterns of asymptomatic Chinese adults using Roussouly classification, the distribution was similar between Chinese males and females; however, from a cross-study comparison, it was different between asymptomatic Chinese and Caucasian adults, with a higher proportion of Roussouly type 3 in Chinese adults.

The Oligomer Polyacrylic Acid Effect on Immobilization of Silver Nanoparticles onto Cotton Fabric to Achieve a Durably Antibacterial Function

Lin Li,Panpan Duan,Qingbo Xu,XuJun Zhang,JiaNing Chen,Feiya Fu,HongYan Diao,Xiangdong Liu 한국섬유공학회 2020 Fibers and polymers Vol.21 No.9

Aiming to a durably antibacterial function, stable immobilization of silver nanoparticles (Ag NPs) on cottontextiles still represents challenging in textile industry. In the present work, by grafting oligomeric polyacrylic acid (PAA) ontocotton fiber surfaces, we effectively prepared the Ag NPs with controllable size on the fiber surface, which are of average sizeof 16.43 nm, and therefore achieved a desirable antibacterial durability. The oligomer PAA binder can give the modifiedfabrics with a remarkable antibacterial durability against washing, as the bacterial reduction rates against bothStaphylococcus aureus and Escherichia coli remained over 90 % even after 50 laundering cycles. Moreover, this graft toapproach using oligomeric PAA shows merits in maintaining the desired cotton properties such as flexibility, waterabsorptivity and vapor permeability. Finally, this finishing process ensures a reliable safety for human skin.

Polyaniline/Cerium Oxide Hybrid Modified Carbon Paste Electrode for Non-Enzymatic Glucose Detection

Jie Zhang,Panpan Guan,Yongjian Li,Wei Li,Qingping Guo 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.7

Measurement, Visualization and Reduction of Micro-Dust

홍승범,류정재,( Panpan Li ),김재규,조성우 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.0

Here we present our bold vision and research plan to measure, visualize and reduce the micro-dust in Korea. Inspired by the portable rapid building energy modeler (RAPMOD) 3-D indoor mapping system, where the user wears a backpack equipped with position and temperature sensors to measure and visualize the temperature inside buildings and transforms the mapping of existing buildings and streamlining integration with energy simulation tools, we plan to use a backpack equipped with position and dust sensors to map the concentration of dust inside buildings. Furthermore, we will design a water bubbler based dust cleaning system integrated with micron-size bubbler plates as well as ozone cleaner, which will drastically reduce the cost of micro-dust cleaning inside buildings.