Effect of Electric Field on the Directly Electrospun Nanofiber Yarns: Simulation and Experimental Study

Shixin Jin,Binjie Xin,Yuansheng Zheng,Shuhua Liu 한국섬유공학회 2018 Fibers and polymers Vol.19 No.1

Electric field plays a key role in electrospinning process for nanofiber and nanofiber yarn producing. The electric field distribution of the yarn manufacturing system is simulated by using finite element method analysis. The effects of electric field distribution and intensity were studied to analyze the influence of the electric field on the electrospun nanofiber yarn surface morphology, mechanical, thermal and water absorption properties. The results show that the morphology anddiameters of nanofiber and yarn were obviously affected by the electric field with changing the needle distance and applied voltage, which further influence the mechanical performance of the yarn. The needle distance does not much affect the thermal property of the PSA electrospun yarn, whereas the yarn obtains better thermal resistance properties at voltage of 25 kV. The nanoyarn electrospun and assembled under higher applied voltage is proved to have a better wicking property in our research.

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.

A Signal Subspace Interference Alignment Scheme with Sum Rate Maximization and Altruistic-Egoistic Bayesian Gaming

( Shixin Peng ),( Yingzhuang Liu ),( Hua Chen ),( Zhengmin Kong ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.6

In this paper, we propose a distributed signal subspace interference alignment algorithm for single beam K-user (K≥3) MIMO interference channel based on sum rate maximization and game theory. A framework of game theory is provided to study relationship between interference signal subspace and altruistic-egoistic bayesian game cost function. We demonstrate that the asymptotic interference alignment under proposed scheme can be realized through a numerical algorithm using local channel state information at transmitters and receivers. Simulation results show that the proposed scheme can achieve the total degrees of freedom that is equivalent to the Cadambe-Jafar interference alignment algorithms with perfect channel state information. Furthermore, proposed scheme can effectively minimize leakage interference in desired signal subspace at each receiver and obtain a moderate average sum rate performance compared with several existing interference alignment schemes. K-3K≥

Historical Opportunity for OBOR and NAPCR’s Strategic Connection

Jiao Shixin 제주평화연구원 2018 JPI Research Series Vol.43 No.-

Historical Opportunity for OBOR and NAPCR's Strategic Connection

Jiao Shixin 제주평화연구원 2018 JPI Peace Net Vol.2018 No.43

A double-layer optimization method for forging process parameters of hinge beam structure and size of intermediate billet

Guizhong Xie,Shixin Zhang,Hao Li,Liangwen Wang,Wenliao Du,Chongmao Zhao,Hangqi Jia 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.10

A double-layer optimization method for the forging process parameters of a hinge beam structure and the design of intermediate billet structure is proposed. First, a primary optimization system for the forging process parameters of hinge beam was established based on orthogonal experiments and range analysis method, and the optimal combination of forging process parameters was selected. On this basis, a mathematical model of the secondary optimization of the final forging of the hinge beam was established. Through radial basis function (RBF) agent model and multi-island genetic algorithm, the secondary optimization of intermediate billet structure of hinge beam was carried out, which improved the grain refinement degree of final forging and reduced the forming load required for forging. Through numerical simulation and optimization design of forging process, the quality and performance of final forging of hinge beam were improved, which has certain guiding significance for the actual production of hinge beam.

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.

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.

Preparation, characterization, and in vivo evaluation of a polymorphic form of valnemulin hydrogen tartrate

Xinle Zhu,Shixin Xu,Lianshou Lu,Shensen Wang,Qi Zhao,Dan Li,Jian Li,Hui Zhao,Bingen Xu 대한수의학회 2019 Journal of Veterinary Science Vol.20 No.2

We prepared a polymorphic form of valnemulin hydrogen tartrate (Form I) to overcome the instability and irritating odor of valnemulin hydrochloride that affect its use in the production and application of veterinary drugs. The physicochemical properties of Form I were characterized by scanning electron microscopy, X-ray powder diffraction, infraredspectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The results showed the crystal structure and thermal properties of Form I were very different from those of a commercially available form of valnemulin hydrogen tartrate (Form II). Form I and Form II were more stable than valnemulin hydrochloride after storage under irradiation and high humidity conditions, respectively. The solubility of Form I was 2.6 times that of Form II, and Form I was selected for use in pharmaceutical kinetics experiments in vivo. Compared to valnemulin hydrochloride, after oral administration at a dose of 10 mg/kg in pigs, Form I had similar pharmaceutical kinetic behavior but a slightly higher area under the concentration– time curve from time zero to the last measurable concentration. Consequently, Form I should be suitable for the development of simple formulations and be effective in the clinical application of veterinary drugs.