Research of the Synthesis and Film Performance of Silica/Poly(St-BA-MPS) Core-Shell Latexes Obtained by Miniemulsion co-Polymerization

Shixin Song,Hanxiao Lv,Yuanjing Bi,Shulin Sun,HuiXuan Zhang 한국고분자학회 2017 Macromolecular Research Vol.25 No.5

Colloid silica nanoparticles were hydrophobic modified by γ-methacryloxypropyl trimethoxysilane (MPS) for the encapsulation into polymer. The alkoxysilane- functionalized core-shell latexes were successfully synthesized via miniemulsion copolymerization of the butyl acrylate, styrene with MPS as the functional monomer in the presence of the modified silica. When these latexes dried at room-temperature, the post-cross-linking occurred due to the alkoxysilane groups on the particle surface and lead to the formation of the films. The morphology of the nanocomposite latexes and the mechanical properties, thermal properties, fire-resistant, optical properties and micro-structure of the resulted films were characterized and discussed. Scanning electron microscope result showed most of the nanoparticles dispersed homogeneously in the polymer matrix when the content of MPS-silica was 10%. However, when the content of MPS-silica nanoparticles was beyond 10%, the aggregation of the nanoparticles became obvious. The tensile test showed that the stress at break increased a lot with the increase of silica content. The thermal and fire-resistant behaviors of the nanocomposite films were improved greatly by the incorporation of silica particles. The optical test showed that the hybrid film was comparable to the pure polymer film at around 84% transmittance.

The Clinical Feature of Behçet’s Disease in Northeastern China

Yingbin Shang,Shixin Han,Jiuhong Li,Qiushi Ren,Fangji Song,Hongduo Chen 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.5

Purpose: Behçet’s disease (BD) is a chronic, relapsing, multi-system vasculitis of unknown aetiology with complicated and diversified clinical features predominantly involving oral and genital ulcers, and ocular and cutaneous lesions. The clinical features of this disease have been described to be different according to geographical areas and gender. We investigated the specific clinical features of BD patients in Northeastern China. Materials and Methods: 116 patients involved in this study fulfilled the classification criteria of the International Study Group for BD. The clinical manifestations and results of laboratory tests of BD were recorded in each patient. Results: The onset was typically between 20-39 years with a slight female predominance. Oral ulcers were the most common manifestation, followed by skin lesions, positive pathergy reaction/genital ulcers, and ocular lesions. Vascular lesion and epididymitis were rare in patients with BD. The frequency of erythema nodosum-like lesion and articular involvement were significantly higher in females, while gastrointestinal involvement was significantly higher in males. The results of laboratory tests showed that the human leukocyte antigen (HLA)-B*51 alleles were positive in 30.9% of patients and the immunological abnormities were present in some patients. Conclusion: The clinical features of BD showed geographical and gender difference. Genetic and immune factors might participate in aetiopathogenesis of BD. Purpose: Behçet’s disease (BD) is a chronic, relapsing, multi-system vasculitis of unknown aetiology with complicated and diversified clinical features predominantly involving oral and genital ulcers, and ocular and cutaneous lesions. The clinical features of this disease have been described to be different according to geographical areas and gender. We investigated the specific clinical features of BD patients in Northeastern China. Materials and Methods: 116 patients involved in this study fulfilled the classification criteria of the International Study Group for BD. The clinical manifestations and results of laboratory tests of BD were recorded in each patient. Results: The onset was typically between 20-39 years with a slight female predominance. Oral ulcers were the most common manifestation, followed by skin lesions, positive pathergy reaction/genital ulcers, and ocular lesions. Vascular lesion and epididymitis were rare in patients with BD. The frequency of erythema nodosum-like lesion and articular involvement were significantly higher in females, while gastrointestinal involvement was significantly higher in males. The results of laboratory tests showed that the human leukocyte antigen (HLA)-B*51 alleles were positive in 30.9% of patients and the immunological abnormities were present in some patients. Conclusion: The clinical features of BD showed geographical and gender difference. Genetic and immune factors might participate in aetiopathogenesis of BD.

Highly sensitive and wearable gel-based sensors with a dynamic physically cross-linked structure for strain-stimulus detection over a wide temperature range

Xia, Shan,Song, Shixin,Li, Yi,Gao, Guanghui The Royal Society of Chemistry 2019 Journal of Materials Chemistry C Vol.7 No.36

<P>Traditional hydrogel sensors can only be applicable in a limited temperature range, such as ambient temperature, since water is easily frozen or evaporated under extreme conditions, which seriously affects their practical application. Here, a highly sensitive wearable strain sensor is fabricated from a flexible, self-healing, anti-freezing and anti-drying gel with a physical cross-linking structure, which is composed of polyacrylic acid, chitosan, and graphene oxide in a mixed solvent of water and glycerol. The dynamic cross-linking enables the network structure and ion channels of the gel to be rapidly recovered and reconstituted, thereby allowing the gel-based strain sensor to display excellent stretchability (more than 1000%) and outstanding sensing performance with a rapid response time of 40 ms, and remarkable repeatability and stability. As a result, the gel can be applied as an epidermal strain sensor for real-time detection of human motions, including joint motions, speaking and breathing. Moreover, the gel can maintain excellent flexibility, stretchability and conductivity over a wide temperature range from −20 °C to 70 °C, which effectively improves the practicality and durability of the gel in practical applications. Therefore, such flexible, conductive, anti-freezing and anti-drying gel may have promising applications in the field of wearable devices, soft robot systems and other applications that need to be applied under changeable conditions.</P>

Performance Improvement of Poly(vinylidene fluoride) by In Situ Copolymerization of Methyl Methacrylate and Ionic Liquid

Xiujie Bi,Shixin Song,Shulin Sun 한국고분자학회 2017 Macromolecular Research Vol.25 No.12

1-Butyl-3-vinylimdazolium tetrafluoroborate ([BVIM][BF4]) was used as ionic liquid to in situ copolymerized with methyl methacrylate (MMA) in poly(vinylidene fluoride) (PVDF) solution by the free radical polymerization method. The content of [BVIM][BF4] in the copolymerized monomers ranges from 0 to 50%. Soxhlet extraction results showed that more than 60% P(MMA-co-[BVIM][BF4]) were grafted onto the PVDF chains and the grafting degree was higher than 15%. 1H NMR tests proved the occurrence of grafting reaction. SEM morphology indicated that phase separation took place for the in situ PVDF/P(MMA-co-[BVIM][BF4]) composites when the [BVIM][BF4] content was more than 40wt%. FTIR and XRD measurements indicated the crystal transformation of PVDF from α-phase to β/γ phase due to the ion-dipole interaction between PVDF and [BVIM][BF4]. Furthermore, the introduction of [BVIM][BF4] into the in situ PVDF/P(MMA-co-[BVIM][BF4]) composites enhanced the electrical conductivity and dielectric constant of PVDF. The present method improved the stability of ionic liquid in the PVDF composites and the in situ PVDF/P(MMA-co-[BVIM][BF4]) composites show potential applications in sensor, actuator and battery fields.

Enhanced Properties of PBT/PC Blends with the Addition of Carboxyl-functionalized Multiwalled Carbon Nanotube

Yuanjiao Hu,Shixin Song,Xue Lv,Shulin Sun 한국고분자학회 2018 폴리머 Vol.42 No.2

Carboxyl-functionalized multiwalled carbon nanotube (c-MWCNT) was used to enhance the properties of poly(butylene terephthalate)/polycarbonate (PBT/PC) blends by melt blending. The c-MWCNT inhibited transesterification reactions between PBT and PC. SEM result showed that most of the c-MWCNT dispersed in the PBT matrix and partial c-MWCNT lied between the interface of PBT and PC phases. c-MWCNT promoted the crystallization of PBT due to the decreased transesterification and the heterogeneous nucleating effect, which led to a 20 oC increase of the crystallization temperature. DMA test indicated that the miscibility between PBT and PC decreased with the c-MWCNT loading since the inhibited transesterification. When the c-MWCNT content was 4 wt%, the yield strength of 65.9 MPa and tensile modulus of 2116MPa were achieved, which corresponded to 23.9 and 19.5% increase relative to the pure PBT/ PC blend. The conductivity and dielectric properties of PBT/PC were largely enhanced by the c-MWCNT. The σdc values of PBT/PC improved greatly by several orders of magnitude from 10-18 to 10-7 when the c-MWCNT content was 2 wt%. The dielectric constant at 100 Hz for the nanocomposites increased from 2.8 to 146 when the c-MWCNT loading varied from 0.1 to 4 wt%, which improved more than 50 times.

ENERGY-SAVING MODEL PREDICTIVE CRUISE CONTROL COMBINED WITH VEHICLE DRIVING CYCLES

SiLun Peng,ZhiHao Xu,JianHua Li,Feng Xiao,Xu Zhang,ShiXin Song,Da Wang,ChunYang Qi,JianFeng Wang 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.2

This study analyzes the problem of adaptive cruise control of vehicles in different driving cycles and divides diverse weight coefficient intervals for the vehicles under the different driving cycles to improve the adaptability of the vehicles in various environments. This paper first describes the driving environment of the adaptive cruise vehicle, and a model prediction algorithm with fixed weight coefficients is established to control the vehicle state. Then, a neural network is established to identify the vehicle driving cycles, the weight intervals are divided in accordance with different driving cycles, and the weight value is dynamically adjusted through fuzzy control. Lastly, the variable weight coefficients of different driving cycles are combined with the model prediction controller. The software cosimulation shows that the method designed in this paper plays a positive role in the fuel economy of adaptive cruise.

Comparative evaluation of fermented ginseng on alleviating antibiotic-associated diarrhea in mice

Qiuyang Li,Pei Yin,Heyu Wang,Lei yu,Shengnan Liu,ShiXin Song,Boyu Xiong,Yunfeng Bi,Lina Wang 한국식품과학회 2024 Food Science and Biotechnology Vol.33 No.12

Antibiotic associated diarrhea (AAD) was a common side effect of antibiotics, and fermented ginseng exhibited potential in treating AAD. In this study, the effects of fermented red, white, and black ginseng on AAD were investigated, with a focus on intestinal flora and inflammation. Clindamycin was used to induce AAD in mice, which caused severe diarrhea and weight loss. However, treatment with fermented ginseng effectively alleviated diarrhea, and reduced inflammation in colonic serosal tissue, thereby mitigating antibiotic-induced intestinal tissue damage. 16S rRNA sequencing revealed that clindamycin disrupted the Bacteroides/Firmicutes ratio (P < 0.001), which was reversed by fermented ginseng treatment. Furthermore, inflammatory cytokines like IL-1β, IL-6, and TNF-α significantly decreased (P < 0.05) after clindamycin treatment but returned to normal levels following fermented ginseng treatment. In conclusion, fermented red, white, or black ginseng (at a dosage of 0.5 g/kg) exhibited efficacy against AAD in mice, reinstating gut flora balance and easing inflammation.