Investigation of Aging Behavior and Thermal Stability of Styrene-Butadiene-Styrene Tri-block Copolymer in Blends

Xiong Xu,Jianying Yu,Canlin Zhang,Song Xu,Lihui Xue,Dong Xie 한국고분자학회 2016 폴리머 Vol.40 No.6

Aging behavior and thermal stability of styrene-butadiene-styrene tri-block copolymer (SBS) in blends were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and thermo-gravimetric analysis (TG). From the analysis of FTIR, the alcohol and carboxyl hydroxyl groups will be gradually generated during the thermal and ultraviolet aging, and the effect of short-term high temperature is more serious than longterm ultraviolet exposure on the structure of SBS; XPS results show that oxygen/carbon ratio of thermal and ultraviolet aged SBS have significantly increased, while the relative concentration of C-O-H(R) is far higher than that of COOH(R); inferred oxidation mechanism of SBS based on the analytical results of FTIR and XPS shows alcohol, carboxyl, ether, ketone, etc. have mainly formed in blends after thermal or ultraviolet aging; moreover, on account of the distribution index of carbon-oxygen binding state of thermal and ultraviolet aged SBS(respectively 3.15 and 1.28), C-O is easily produced than C=O and the effect of thermal aging is more obvious; from the results of TG, the maximum decomposition rate and temperature decrease after aging.

The fuzzy comprehensive evaluation (FCE) and the principal component analysis (PCA) model simulation and its applications in water quality assessment of Nansi Lake Basin, China

Shiguo Xu,Yixiao Cui,Chuanxi Yang,Shujing Wei,Wenping Dong,Lihui Huang,Changqing Liu,Zongming Ren,Weiliang Wang 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.2

The Fuzzy Comprehensive Evaluation (FCE) and the Principal Component Analysis (PCA) were simulated to assess water quality of the Nansi Lake Basin, China. The membership functions were established via the Nor-Half Sinusoidal Distribution Method, and the weight was calculated via the Exceeding Standard Multiple Method. To enhance the efficiency of extracting principal pollutant, the eigenequation was solved through the Jacobi Method, and the principal components were extracted based on eigenvalue, contribution ratio, accumulating contribution ratio, principal component loading and score. Water quality classification based on “National Surface Water Environmental Quality Standards of China (GB3838-2002) was used to assess the water quality. Considering the difference of the temporal and spatial distribution in average, water quality of Level I was 28.9%, 28.1%, 25.1%, 25.6%, respectively in spring, summer, autumn, and winter, which suggested that water quality in spring and summer was better than in autumn and winter. The order of water quality was Zhaoyang Lake (Level I) > Nanyang Lake (Level I) > Dushan Lake (Level III) > Weishan Lake (Level III and IV). There were four extracted principal components that can replace the fourteen pollutant indexes for assessing water quality. According to the annual mean data of the 1<SUP>st</SUP> principal components, the most important pollutions were heavy metals, including As (0.933), Hg (0.931), Cd (0.929), Cr(VI) (0.926), Pb (0.925), and Cu (0.534). It is proved that the combined FCE-PCA model could provide valuable information in the water quality assessment for the Nansi Lake Basin.

The visible and ultraviolet organic light-emitting diodes with germanium dioxide as facile solution-processed anode buffer layer

Kai Xu,Zhenchang Tang,Yan Zhang,Wanshu Li,Haiou Li,Lihui Wang,Li-Ming Liu,Hong-Hang Wang,Feng Chi,Xiaowen Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.10

Germanium dioxide (GeO2) aqueous solutions are facilely prepared and the corresponding anode buffer layers (ABLs) with solution process are demonstrated. Atomic force microscopy, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy measurements show that solution-processed GeO2 behaves superior film morphology and enhanced work function. Using GeO2 as ABL of organic light-emitting diodes (OLEDs), the visible device with tris(8-hydroxy-quinolinato)aluminium as emitter gives maximum luminous efficiency of 6.5 cd/A and power efficiency of 3.5 lm/W, the ultraviolet device with 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl- 1,2,4-triazole as emitter exhibits short-wavelength emission with peak of 376 nm, full-width at halfmaximum of 42 nm, maximum radiance of 3.36 mW/cm2 and external quantum efficiency of 1.5%. The performances are almost comparable to the counterparts with poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) as ABL. The current, impedance, phase and capacitance as a function of voltage characteristics elucidate that the GeO2 ABL formed from appropriate concentration of GeO2 aqueous solution favors hole injection enhancement and accordingly promoting device performance.

Lactate exacerbates lung damage induced by nanomicroplastic through the gut microbiota–HIF1a/PTBP1 pathway

Xuan Lihui,Xu Zheng,Luo Jinhua,Yin Wang,Yan Yuhui,Qu Can,Xie Zuozhong,Skonieczna Magdalena,Zhou Ping-Kun,Huang Ruixue 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Exposure to nanomicroplastics (nano-MPs) can induce lung damage. The gut microbiota is a critical modulator of the gut–lung axis. However, the mechanisms underlying these interactions have not been elucidated. This study explored the role of lactate, a key metabolite of the microbiota, in the development of lung damage induced by nano-MPs (LDMP). After 28 days of exposure to nano-MPs (50–100 nm), mice mainly exhibited damage to the lungs and intestinal mucosa and dysbiosis of the gut microbiota. Lactate accumulation was observed in the lungs, intestines and serum and was strongly associated with the imbalance in lactic acid bacteria in the gut. Furthermore, no lactate accumulation was observed in germ-free mice, while the depletion of the gut microbiota using a cocktail of antibiotics produced similar results, suggesting that lactate accumulation in the lungs may have been due to changes in the gut microbiota components. Mechanistically, elevated lactate triggers activation of the HIF1a/PTBP1 pathway, exacerbating nano-MP-induced lung damage through modulation of the epithelial–mesenchymal transition (EMT). Conversely, mice with conditional knockout of Ptbp1 in the lungs (Ptbp1flfl) and PTBP1-knockout (PTBP1-KO) human bronchial epithelial (HBE) cells showed reversal of the effects of lactate through modulation of the HIF1a/PTBP1 signaling pathway. These findings indicate that lactate is a potential target for preventing and treating LDMP.

$H_{\infty}$ filter for flexure deformation and lever arm effect compensation in M/S INS integration

Liu, Xixiang,Xu, Xiaosu,Wang, Lihui,Li, Yinyin,Liu, Yiting The Society of Naval Architects of Korea 2014 International Journal of Naval Architecture and Oc Vol.6 No.3

On ship, especially on large ship, the flexure deformation between Master (M)/Slave (S) Inertial Navigation System (INS) is a key factor which determines the accuracy of the integrated system of M/S INS. In engineering this flexure deformation will be increased with the added ship size. In the M/S INS integrated system, the attitude error between MINS and SINS cannot really reflect the misalignment angle change of SINS due to the flexure deformation. At the same time, the flexure deformation will bring the change of the lever arm size, which further induces the uncertainty of lever arm velocity, resulting in the velocity matching error. To solve this problem, a $H_{\infty}$ algorithm is proposed, in which the attitude and velocity matching error caused by deformation is considered as measurement noise with limited energy, and measurement noise will be restrained by the robustness of $H_{\infty}$ filter. Based on the classical "attitude plus velocity" matching method, the progress of M/S INS information fusion is simulated and compared by using three kinds of schemes, which are known and unknown flexure deformation with standard Kalman filter, and unknown flexure deformation with $H_{\infty}$ filter, respectively. Simulation results indicate that $H_{\infty}$ filter can effectively improve the accuracy of information fusion when flexure deformation is unknown but non-ignorable.

H∞ filter for flexure deformation and lever arm effect compensation in M/S INS integration

Xixiang Liu,Xiaosu Xu,Lihui Wang,Yiting Liu 대한조선학회 2014 International Journal of Naval Architecture and Oc Vol.6 No.3

On ship, especially on large ship, the flexure deformation between Master (M)/Slave (S) Inertial Naviga-tion System (INS) is a key factor which determines the accuracy of the integrated system of M/S INS. In engineering this flexure deformation will be increased with the added ship size. In the M/S INS integrated system, the attitude error between MINS and SINS cannot really reflect the misalignment angle change of SINS due to the flexure deformation. At the same time, the flexure deformation will bring the change of the lever arm size, which further induces the uncertainty of lever arm velocity, resulting in the velocity matching error. To solve this problem, a H∞ algorithm is proposed, in which the attitude and velocity matching error caused by deformation is considered as measurement noise with limited energy, and measurement noise will be restrained by the robustness of H∞ filter. Based on the classical “attitude plus velocity” matching method, the progress of M/S INS information fusion is simulated and compared by using three kinds of schemes, which are known and unknown flexure deformation with standard Kalman filter, and unknown flexure deformation with H∞ filter, respectively. Simulation results indicate that H∞ filter can effectively improve the accuracy of information fusion when flexure deformation is unknown but non-ignorable.

The molecular characteristics of two metallothioneins in Ostrinia furnacalis and expression under conditions of heavy metal stress

Zhang Jiali,Guo Xin,Xu Fanshu,Chen Lihui,Wei Hongyi 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.1

Metallothioneins are ubiquitously-expressed metal-binding proteins. Despite their potential ecological relevance, no prior reports have identified any metallothioneins in Ostrinia furnacalis or other Lepidoptera species. A better understanding of the molecular characteristics and regulatory dynamics of metallothionein genes in O. furnacalis under heavy metal stress conditions would enable future studies of the roles played by these proteins in the context of heavy metal detoxification. Herein, we identified and characterized two metallothionein (OfMT) genes in O. furnacalis, including the 147 bp OfMT1 gene encoding a 48 amino acid protein containing 10 cysteine residues, and the 141 bp OfMT2 gene encoding a 46 amino acid protein containing 12 cysteine residues. The expression of OfMT2 was found to be related to Cu and Cd concentrations in a dose-dependent manner but was unaffected by Zn exposure. Overall, these results indicate that OfMT genes likely encode metal-binding proteins consistent with their potential role in the maintenance of heavy metal homeostasis.

Rapid Detection of SdhBP225F and SdhBH272R Mutations in Boscalid Resistant Botrytis cinerea Strains by ARMS-PCR

Xin Liu,Rong Zeng,Shigang Gao,Lihui Xu,Fuming Dai 한국식물병리학회 2019 Plant Pathology Journal Vol.35 No.1

SdhBP225Fand SdhBH272R mutations have been found associated with boscalid resistance in Botrytis cinerea from strawberry in Shanghai, China. For rapid detection of two mutations, tetra-primers were designed and optimized to gain the relatively high accuracy and specificity based on the ARMS-PCR technique, by which resistance can be identified with different lengths of products on agarose gels. The tetra-primer ARMS-PCR systems for SdhBP225F and SdhBH272R were validated by 9 SdhB-squenced strains repeatedly. Then, sensitivity of 30 more strains were also tested by the methods, which were accordant with genotypes by sequencing and the sensitivity of conidial germination to boscalid by 100%. Thus, the methods developed in this study are proved to be rapid, inexpensive, accurate and practical for resistance detection of Botrytis cinerea caused by SdhBP225F and SdhBH272R mutations.

Solution-processed WOx hole injection layer for efficient fluorescent blue organic light-emitting diode

Wanshu Li,Yan Zhang,Qinghong Zheng,Kai Xu,Xiuyun Zhang,Liming Liu,Bin Wei,Lihui Wang,Jiwen Xu,Xiaowen Zhang 한국물리학회 2018 Current Applied Physics Vol.18 No.5

Solution-processed tungsten oxide (s-WOx) interfacial layer for efficient hole injection in fluorescent blue organic light-emitting diode (OLED) is demonstrated. The OLED using 2-methyl-9,10-bis(naphthalen-2- yl)anthracene (MADN) as emitter shows luminous efficiency of 3.3 cd/A, power efficiency of 2.5 lm/W and external quantum efficiency of 4.6% with Commission Internationale d'Eclairage (CIE) color coordinates of (0.154, 0.102). Using MADN doped 1-4-di-[4-(N,N-diphenyl)amino]styryl-benzene as emitter, luminous efficiency of 10.8 cd/A, power efficiency of 6.4 lm/W and external quantum efficiency of 7.2% with CIE color coordinates of (0.167, 0.283) are achieved. Atomic force microscopy and X-ray photoelectron spectroscopy show that s-WOx features superior film morphology and non-stoichiometry with slight oxygen deficiency. Current-voltage characteristics and impedance spectroscopy analysis indicate that s-WOx behaves slightly enhanced hole injection and accordingly contributes to improved device performance in comparison with conventional vacuum thermal evaporation WOx. Our results pave an alternative way for broadeningWOx application with solution process and advancing fluorescent blue OLEDs.

Sensor-less external force detection for industrial manipulators to facilitate physical human-robot interaction

Bitao Yao,Zu-De Zhou,Lihui Wang,Wenjun Xu,Quan Liu 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

Sensor-less external force detection is important for industrial robots which are usually not equipped with external force sensors to be applied in physical human-robot interaction (pHRI). This paper adopts the dynamic models of the robot in both dynamic mode and quasistatic mode to detect the external force. In the dynamic mode, the inertia and friction parameters of the robot are identified with the weighted least squares. The excitation trajectory for parameter identification is optimised. The un-modelled peak points in the joint torque residual are removed by a statistical method. The torque changes of joints in quasi-static mode which are equivalent to the joint pre-sliding friction is modelled with a lumped parameter model, generalised Maxwell slip (GMS) element model. Therefore, there is no need for the switching between the friction models in different modes and this and facilitates the application of dynamic model in the external force detection. The dynamic models of robots both in dynamic mode and quasi-static mode and their effectiveness for external force detection in pHRI are verified by experimental results.