A model to characterize the effect of particle size of fly ash on the mechanical properties of concrete by the grey multiple linear regression

Yunpeng Cui,Jun Liu,Licheng Wang,Runqing Liu,Bo Pang 사단법인 한국계산역학회 2020 Computers and Concrete, An International Journal Vol.26 No.2

Fly ash has become an important component of concrete as supplementary cementitious material with the development of concrete technology. To make use of fly ash efficiently, four types of fly ash with particle size distributions that are in conformity with four functions, namely, S.Tsivilis, Andersen, Normal and F distribution, respectively, were prepared. The four particle size distributions as functions of the strength and pore structure of concrete were thereafter constructed and investigated. The results showed that the compressive and flexural strength of concrete with the fly ash that conforming to S.Tsivilis, Normal, F distribution increased by 5-10 MPa and 1-2 MPa, respectively, compared to the reference sample at 28 d. The pore structure of the concrete was improved, in which the total porosity of concrete decreased by 2-5% at 28 d. With regarding to the fly ash with Andersen distribution, it was however not conducive to the strength development of concrete. Regression model based on the grey multiple linear regression theory was proved to be efficient to predict the strength of concrete, according to the characteristic parameters of particle size and pore structure of the fly ash.

GOP Adaptation Coding of H.264/SVC Based on Precise Positions of Video Cuts

( Yunpeng Liu ),( Renfang Wang ),( Huixia Xu ),( Dechao Sun ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.7

Hierarchical B-frame coding was introduced into H.264/SVC to provide temporal scalability and improve coding performance. A content analysis-based adaptive group of picture structure (AGS) can further improve the coding efficiency, but damages the inter-frame correlation and temporal scalability of hierarchical B-frame to different degrees. In this paper, we propose a group of pictures (GOP) adaptation coding method based on the positions of video cuts. First, the cut positions are accurately detected by the combination of motion coherence (MC) and mutual information (MI); then the GOP is adaptively and proportionately set by the analysis of MC in one scene. In addition, we propose a binary tree algorithm to achieve the temporal scalability of any size of GOP. The results for test sequences and real videos show that the proposed method reduces the bit rate by up to about 15%, achieves a performance gain of about 0.28-1.67 dB over a fixed GOP, and has the advantages of better transmission resilience and video summaries.

Echinacoside Ameliorates Cyclophosphamide-Induced Bladder Damage in Mice

Yunpeng Shao,Yu Liu,Baixin Shen,Qiao Zhou,Zhongqing Wei 한국식품영양과학회 2022 Journal of medicinal food Vol.25 No.7

Interstitial cystitis (IC) is featured by apoptosis and chronic inflammation in bladder tissue. We aimed to evaluate the effect of echinacoside (ECH), which is known to modulate inflammation and apoptosis on IC using relevant models. We established a mouse model of cystitis using cyclophosphamide (CYP) and treated human urothelium cells (SV-HUC-1) with lipopolysaccharide (LPS) + ATP as in vitro model. The bladder function was tested by urodynamics. Apoptosis of bladder cells was assessed by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Expressions of apoptosis-associated and inflammation-related proteins were assessed using western blotting. Treatment with ECH significantly improved bladder function, reduced inflammatory damage, and decreased apoptosis in the models. Furthermore, ECH decreased the phosphorylation levels of IκB and NF-κB(p65), and upregulated the expression of peroxisome proliferator-activated receptor gamma (PPARγ), which are related to apoptosis and inflammation in CYP-induced mouse cystitis. Moreover, ECH did not reduce apoptosis of urothelial cells after treatment with PPARγ antagonist GW9662. Our findings suggest that ECH might have protective effect against IC in bladder and be mediated through modulation of the PPARγ/NF-κB pathway.

Declined Preoperative Aspartate Aminotransferase to Neutrophil Ratio Index Predicts Poor Prognosis in Patients with Intrahepatic Cholangiocarcinoma after Hepatectomy

Lingyun Liu,Wei Wang,Yi Zhang,Jianting Long,Zhaohui Zhang,Qiao Li,Bin Chen,Shaoqiang Li,Yunpeng Hua,Shunli Shen,Baogang Peng 대한암학회 2018 Cancer Research and Treatment Vol.50 No.2

Purpose Various inflammation-based prognostic biomarkers such as the platelet to lymphocyte ratio and neutrophil to lymphocyte ratio, are related to poor survival in patients with intrahepatic cholangiocarcinoma (ICC). This study aims to investigate the prognostic value of the aspartate aminotransferase to neutrophil ratio index (ANRI) in ICC after hepatic resection. Materials and Methods Data of 184 patients with ICC after hepatectomy were retrospectively reviewed. The cut-off value of ANRI was determined by a receiver operating characteristic curve. Preoperative ANRI and clinicopathological variables were analyzed. The predictive value of preoperative ANRI for prognosis of ICC was identified by univariate and multivariate analyses. Results The optimal cut-off value of ANRI was 6.7. ANRI was associated with tumor size, tumor recurrence, white blood cell, neutrophil count, aspartate aminotransferase, and alanine transaminase. Univariate analysis showed that ANRI, sex, tumor number, tumor size, tumor differentiation, lymph node metastasis, resection margin, clinical TNM stage, neutrophil count, and carcinoembryonic antigen were markedly correlated with overall survival (OS) and disease-free survival (DFS) in patients with ICC. Multivariable analyses revealed that ANRI, a tumor size > 6 cm, poor tumor differentiation, and an R1 resection margin were independent prognostic factors for both OS and DFS. Additionally, preoperative ANRI also had a significant value to predict prognosis in various subgroups of ICC, including serum hepatitis B surface antigennegative and preoperative elevated carbohydrate antigen 19-9 patients. Conclusion Preoperative declined ANRI is a noninvasive, simple, and effective predictor of poor prognosis in patients with ICC after hepatectomy.

Quinetides: diverse posttranslational modified peptides of ribonuclease-like storage protein from Panax quinquefolius as markers for differentiating ginseng species

Qiang Zhao,Yunpeng Bai,Dan Liu,Nan Zhao,Huiyuan Gao,Xiaozhe Zhang 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.5

Background: Peptides have diverse and important physiological roles in plants and are ideal markers for species identification. It is unclear whether there are specific peptides in Panax quinquefolius L. (PQ). The aims of this study were to identify Quinetides, a series of diverse posttranslational modified native peptides of the ribonuclease-like storage protein (ginseng major protein), from PQ to explore novel peptide markers and develop a new method to distinguish PQ from Panax ginseng. Methods: We used different fragmentation modes in the LTQ Orbitrap analysis to identify the enriched Quinetide targets of PQ, and we discovered Quinetide markers of PQ and P. ginseng using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry analysis. These “peptide markers” were validated by simultaneously monitoring Rf and F11 as standard ginsenosides. Results: We discovered 100 Quinetides of PQ with various post-translational modifications (PTMs), including a series of glycopeptides, all of which originated from the protein ginseng major protein. We effectively distinguished PQ from P. ginseng using new “peptide markers.” Four unique peptides (Quinetides TP6 and TP7 as markers of PQ and Quinetides TP8 and TP9 as markers of P. ginseng) and their associated glycosylation products were discovered in PQ and P. ginseng. Conclusion: We provide specific information on PQ peptides and propose the clinical application of peptide markers to distinguish PQ from P. ginseng.

Epsilon-Fe₂O₃ is a novel intermediate for magnetite biosynthesis in magnetotactic bacteria

Tong Wen,Yunpeng Zhang,Yuanyuan Geng,Junquan Liu,Abdul Basit,Jiesheng Tian,Ying Li,Ji-Lun Li,Jing Ju,Wei Jiang 한국생체재료학회 2019 생체재료학회지 Vol.23 No.3

Background: Natural biological magnetite nanoparticles are widely distributed from microorganisms to humans. It is found to be very important in organisms, especially in navigation. Moreover, purified magnetite nanoparticles also have potential applications in bioengineering and biomedicine. Magnetotactic bacteria (MTB) is considered one of the most abundant species around the world which can form intracellular membrane enveloped magnetic nanoparticles, referred to as magnetosomes. To our knowledge, the biomineralization of magnetosome in MTB involves a serious of genes located on a large unstable genomic region named magnetosome island, which specially exists in MTB. The magnetite core of magnetosome formed via a Fe (III) ion intermediates, for instance, α-Fe2O3 and ferrihydrite. Though the biosynthesis of magnetosome represents a general biomineralization mechanism of biogenic magnetite, knowledge of magnetosome biosynthesis and biomineralization remains very limited. Method: Cells used in this study were cultured in a 7.5-L bioreactor, samples for intermediate capture were taken each certain time interval after the generation of magnetosome biosynthesis condition. High-resolution transmission electron microscopy were used to analyze the detailed structure of magnetosomes. The parameters of the crystal structures were obtained by Fast Fourier Transform analyses. Results: In this study, we identified a novel intermediate phase, ε-Fe2O3, during the magnetite maturation process in MTB via kinetic analysis. Unlike α-Fe2O3, which has been reported as a precursor during magnetosome biosynthesis in MTB before, ε-Fe2O3, due to its thermal instability, is a rare phase with scarce natural abundance. This finding confirmed that ε-Fe2O3 is an important novel intermediate during the biomineralization of magnetosome in MTB, and shed new light on the magnetosome biosynthesis pathway.

Study on the irradiation effect of mechanical properties of RPV steels using crystal plasticity model

Junfeng Nie,Yunpeng Liu,Qihao Xie,Zhanli Liu 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.2

In this paper a body-centered cubic(BCC) crystal plasticity model based on microscopic dislocationmechanism is introduced and numerically implemented. The model is coupled with irradiation effect viatracking dislocation loop evolution on each slip system. On the basis of the model, uniaxial tensile tests ofunirradiated and irradiated RPV steel(take Chinese A508-3 as an example) at different temperatures aresimulated, and the simulation results agree well with the experimental results. Furthermore, crystalplasticity damage is introduced into the model. Then the damage behavior before and after irradiation isstudied using the model. The results indicate that the model is an effective tool to study the effect ofirradiation and temperature on the mechanical properties and damage behavior.

Neutron-irradiated effect on the thermoelectric properties of Bi2Te3-based thermoelectric leg

Zhao Huanyu,Liu Kai,Xu Zhiheng,Liu Yunpeng,Tang Xiaobin 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.8

Thermoelectric (TE) materials working in radioisotope thermoelectric generators are irradiated by neutrons throughout its service; thus, investigating the neutron irradiation stability of TE devices is necessary. Herein, the influence of neutron irradiation with fluences of 4.56 1010 and 1 1013 n/cm2 by pulsed neutron reactor on the electrical and thermal transport properties of n-type Bi2Te2.7Se0.3 and ptype Bi0.5Sb1.5Te3 thermoelectric alloys prepared by cold-pressing and molding is investigated. After neutron irradiation, the properties of thermoelectric materials fluctuate, which is related to the material type and irradiation fluence. Different from p-type thermoelectric materials, neutron irradiation has a positive effect on n-type Bi2Te2.7Se0.3 materials. This result might be due to the increase of carrier mobility and the optimization of electrical conductivity. Afterward, the effects of p-type and n-type TE devices with different treatments on the output performance of TE devices are further discussed. The positive and negative effects caused by irradiation can cancel each other to a certain extent. For TE devices paired with p-type Bi0.5Sb1.5Te3 and n-type Bi2Te2.7Se0.3 thermoelectric legs, the generated power and conversion efficiency are stable after neutron irradiation.

Simulation of the irradiation effect on hardness of Chinese HTGR A508-3 steels with CPFEM

Junfeng Nie,Pandong Lin,Yunpeng Liu,Haiquan Zhang,Xin Wang 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.8

Understanding the irradiation hardening effect of structural steels under various irradiation conditions plays an important role in developing advanced nuclear systems. Such being the case, a crystal plasticity model for body-centered cubic (BCC) crystal based on the density of dislocations and irradiation defects is summarized and numerically implemented in this paper. Based on this model, nano-indentation hardness of Chinese A508-3 steels with ion irradiation is calculated. Very good agreement is observed between simulation and experimental data of several different irradiation doses subjected to various operating temperatures, from which, it can be concluded that indentation hardness increases with increasing irradiation dose at both room temperature and high temperature. Consequently, the validity of this model has been proved properly, and furthermore, the model established in this paper could guide the study of irradiation hardening effect and temperature effect to some extent.

A Fluorinated Polythiophene Derivative with Stabilized Backbone Conformation for Highly Efficient Fullerene and Non-Fullerene Polymer Solar Cells

Zhang, Shaoqing,Qin, Yunpeng,Uddin, Mohammad Afsar,Jang, Bomee,Zhao, Wenchao,Liu, Delong,Woo, Han Young,Hou, Jianhui American Chemical Society 2016 Macromolecules Vol.49 No.8

<P>Here, taking a polythiophene derivative (PBDD4T) as a starting polymer, we tried to increase the rotation barrier and hence stabilize its backbone conformation by introducing fluorine into the beta and beta'-position of the alpha-linked bithiophene segments and then synthesized a new polymer named as PBDD4T-2F. Our results demonstrate that the rotation barrier between the a-linked bithiophene significantly increases after the fluorination, so PBDD4T-2F has a more stable backbone conformation than PBDD4T. Compared to PBDD4T, PBDD4T-2F shows stronger aggregation effect in solution state and more compact pi-pi stacking in solid thin film and also possesses deeper HOMO level. These properties make PBDD4T-2F being an ideal donor material in PSCs. When blended with PC71BM, a fullerene acceptor, the PBDD4T-2F-based device showed a power conversion efficiency (PCE) of 9.04%, which is 38% higher than that of the PBDD4T-based device; when blended with ITIC, a non-fullerene acceptor, the PBDD4T-2F-based device showed a PCE of 8.69%, which is almost 20 times higher than that of the PBDD4T-based device. What is more, the tandem cell, in which the blend of PBDD4T-2F:PC61BM was used for making the front subcell, exhibited a high PCE of 10.12%. The photovoltaic results indicate that the fluorination is an effective method to enhance interchain pi-pi interaction for the polythiophene and hence to tune its photovoltaic properties in PSCs, especially for the fullerene-free device based on ITIC.</P>