Solution Blowing of Polyacrylonitrile Nanofiber Mats Containing Fluoropolymer for Protective Applications

Xiaojie Li,Shiying Teng,Xianlin Xu,Hang Wang,Feng Dong,Xupin Zhuang,Bo-wen Cheng 한국섬유공학회 2018 Fibers and polymers Vol.19 No.4

A new type of hydrophobic polyacrylonitrile (PAN) nanofiber is fabricated by solution blowing of a blend solution of fluorine-containing polyacrylate (FPA) and PAN. The nanofibers’ surface composition, hydrophobicity, and protection ability were evaluated to clarify the effects of FPA addition. Results revealed that FPA addition increased the nanofiber diameter, as well as enhanced the hydrophobicity and transport properties of the nanofiber mats. The mats had average water contact angles of 123.44 o, 132.11 o, and 137.11 o for FPA contents of 0.66 wt%, 1.98 wt%, and 3.30 wt%, respectively. All these results suggested the potential of the solution blowing nanofiber mats as protection materials.

Immobilization of Coacervate Microcapsules in Multilayer Sodium Alginate Beads for Efficient Oral Anticancer Drug Delivery

Feng, Chao,Song, Ruixi,Sun, Guohui,Kong, Ming,Bao, Zixian,Li, Yang,Cheng, Xiaojie,Cha, Dongsu,Park, Hyunjin,Chen, Xiguang American Chemical Society 2014 Biomacromolecules Vol.15 No.3

<P>We have designed and evaluated coacervate microcapsules-immobilized multilayer sodium alginate beads (CMs-M-ALG-Beads) for oral drug delivery. The CMs-M-ALG-Beads were prepared by immobilization of doxorubicin hydrochloride (DOX) loaded chitosan/carboxymethyl coacervate microcapsules (DOX:CS/CMCS-CMs) in the core and layers of the multilayer sodium alginate beads. The obtained CMs-M-ALG-beads exhibited layer-by-layer structure and rough surface with many nanoscale particles. The swelling characteristic and drug release results indicated that 4-layer CMs-M-ALG-Beads possessed favorable gastric acid tolerance (the swelling rate <5%, the cumulative drug release rate <3.8%). In small intestine, the intact DOX:CS/CMCS-CMs were able to rapidly release from CMs-M-ALG-Beads with the dissolution of ALG matrix. Ex vivo intestinal mucoadhesive and permeation showed that CMs-M-ALG-Beads exhibited continued growth for <I>P</I><SUB>app</SUB> values of DOX, which was 1.07–1.15 folds and 1.28–1.38 folds higher than DOX:CS:CMCS-CMs in rat jejunum and ileum, respectively, demonstrating that CMs-M-ALG-Beads were able to enhance the absorption of DOX by controlled releasing DOX:CS/CMCS-CMs and prolonging the contact time between the DOX:CS/CMCS-CMs and small intestinal mucosa.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/bomaf6/2014/bomaf6.2014.15.issue-3/bm401890x/production/images/medium/bm-2013-01890x_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/bm401890x'>ACS Electronic Supporting Info</A></P>

A Dynamic Power Distribution Strategy for Large-scale Cascaded Photovoltaic Systems

Kangan Wang,Xiaojie Wu,Fujin Deng,Feng Liu 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.5

The cascaded H-bridge (CHB) multilevel converter is a promising topology for large-scale photovoltaic (PV) systems. The output voltage over-modulation derived by the inter-module active power imbalance is one of the key issues for CHB PV systems. This paper proposed a dynamic power distribution strategy to eliminate the over-modulation in a CHB PV system by suitably redistributing the reactive power among the inverter modules of the CHB PV system. The proposed strategy can effectively extend the operating region of the CHB PV system with a simple control algorithm and easy implementation. Simulation and experimental results carried out on a seven-level CHB grid-connected PV system are shown to validate the proposed strategy.

A Dynamic Power Distribution Strategy for Large-scale Cascaded Photovoltaic Systems

Wang, Kangan,Wu, Xiaojie,Deng, Fujin,Liu, Feng The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.5

The cascaded H-bridge (CHB) multilevel converter is a promising topology for large-scale photovoltaic (PV) systems. The output voltage over-modulation derived by the inter-module active power imbalance is one of the key issues for CHB PV systems. This paper proposed a dynamic power distribution strategy to eliminate the over-modulation in a CHB PV system by suitably redistributing the reactive power among the inverter modules of the CHB PV system. The proposed strategy can effectively extend the operating region of the CHB PV system with a simple control algorithm and easy implementation. Simulation and experimental results carried out on a seven-level CHB grid-connected PV system are shown to validate the proposed strategy.

Clinical application of sartorius tendon transposition during radical vulvectomy: a case control study of 58 cases at a single institution

Lei Li,Xinxin Kou,Xiaojie Feng,Fenghua Liu,Hongtu Chao,Liying Wang 대한부인종양학회 2015 Journal of Gynecologic Oncology Vol.26 No.4

Objective: The aim of this study was to investigate the clinical effects of sartorius tendon transposition versus sartorius transposition during bilateral inguinal lymphadenectomy of radical vulvectomy. Methods: A total of 58 vulvar cancer patients who had surgery from May 2007 to October 2013, in which 30 patients received sartorius transposition and 28 patients received sartorius tendon transposition. All patients were matched by age, body mass index, stage, histology, and grade. Intraoperative variables and postoperative complications, recurrence, progression-free survival (PFS), and overall survival (OS) and postoperative life quality were compared and analyzed. Results: No significant differences were found at median surgical times and amounts of bleeding (p=0.316 and p=0.249, respectively), neither at the incidences of groin cellulitis and lymphocele (p=0.673 and p=0.473, respectively), but the recovery times of the inguinal wounds were shorter (p=0.026) and the incidences of wound break and chronic lymphedema were significantly decreased in the tendon transposition group (p=0.012 and p=0.022, respectively). Postoperative quality of life in tendon transposition group was significantly improved as indicated by the EORTC QLQ-C30 questionnaire. Recurrences were similar (p=0.346) and no significant differences were found at PFS and OS (p=0.990 and p=0.683, respectively). Conclusion: Compared to sartorius transposition, sartorius tendon transposition during inguinal lymphadenectomy led to improved patient recovery, reduced postoperative complications, and improved life quality without compromising the outcomes.

Path Following of Underactuated Unmanned Surface Vehicle Based on Trajectory Linearization Control with Input Saturation and External Disturbances

Bingbing Qiu,Guo-Feng Wang,Yun-Sheng Fan,Dong-Dong Mu,Xiaojie Sun 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.8

This paper investigates the path following control problem for underactuated unmanned surface vehicle(USV) in the presence of unmodeled dynamics, external disturbances and input saturation. A novel adaptive robustpath following control scheme is proposed by employing trajectory linearization control (TLC) technology andfinite-time disturbance observer, which is composed of a concise yaw rate controller and a surge speed controller. The salient features of the proposed scheme include: a path following guidance law is designed to ensure USVeffectively converging to and following the desired path; TLC is introduced into the field of USV motion controlas new effective technique, and it is the first time used to design path following controller for underactuated USV;a finite-time nonlinear tracking differentiator is constructed not only to avoid the signal jump caused by derivation,but also to filter noise and high frequency interference. A finite-time disturbance observer (FDO) is devised toexactly observe the uncertain dynamics and unknown external disturbances, which improves the tracking accuracyand precise disturbance rejection of the proposed controller; then, an auxiliary dynamic system that is governed bysmooth switching function is developed to compensate for the saturation constraint on actuator. Stability analysisverifies that all signals in the closed-loop system are uniformly ultimately bounded. Finally, simulation results andcomparisons illustrate the superiority of the proposed control scheme.

Spinal Cord Ependymoma Associated with Neurofibromatosis 1 : Case Report and Review of the Literature

Cheng, Hongwei,Shan, Ming,Feng, Chunguo,Wang, Xiaojie The Korean Neurosurgical Society 2014 Journal of Korean neurosurgical society Vol.55 No.1

Patients with neurofibromatosis 1 (NF1) are predisposed to develop central nervous system tumors, due to the loss of neurofibromin, an inactivator of proto-oncogene Ras. However, to our knowledge, only three cases of ependymomas with NF1 have been reported in the literature. The authors present a case of NF1 patient with a spinal cord ependymoma. She was referred for about half a year history of increasing numbness that progressed from her fingers to her entire body above the bellybutton. Magnetic resonance imaging revealed a relative-demarcated, heterogeneously enhanced mass lesion accompanied by perifocal edema in C5-7 level, a left-sided T11 spinous process heterogeneously enhanced mass in soft tissue, intervertebral disk hernia in L2-5 level, and widespread punctum enhancing lesion in her scalp and in T11-L5 level. The patient underwent C5-7 laminectomies and total excision of the tumor under operative microscope, and intraoperative ultrasonography and physiological monitoring were used during the surgery. Histopathologically, her tumor was found to be a ependymoma without malignant features (grade II in the World Health Organization classification). Therefore, no adjuvant therapy was applied. Following the operation, the patient showed an uneventful clinical recovery with no evidence of tumor recurrence after one year of follow-up.

Influencing Factors Analysis of Facial Nerve Function after the Microsurgical Resection of Acoustic Neuroma

Hong, WenMing,Cheng, HongWei,Wang, XiaoJie,Feng, ChunGuo The Korean Neurosurgical Society 2017 Journal of Korean neurosurgical society Vol.60 No.2

Objective : To explore and analyze the influencing factors of facial nerve function retainment after microsurgery resection of acoustic neurinoma. Methods : Retrospective analysis of our hospital 105 acoustic neuroma cases from October, 2006 to January 2012, in the group all patients were treated with suboccipital sigmoid sinus approach to acoustic neuroma microsurgery resection. We adopted researching individual patient data, outpatient review and telephone followed up and the House-Brackmann grading system to evaluate and analyze the facial nerve function. Results : Among 105 patients in this study group, complete surgical resection rate was 80.9% (85/105), subtotal resection rate was 14.3% (15/105), and partial resection rate 4.8% (5/105). The rate of facial nerve retainment on neuroanatomy was 95.3% (100/105) and the mortality rate was 2.1% (2/105). Facial nerve function when the patient is discharged from the hospital, also known as immediate facial nerve function which was graded in House-Brackmann : excellent facial nerve function (House-Brackmann I-II level) cases accounted for 75.2% (79/105), facial nerve function III-IV level cases accounted for 22.9% (24/105), and V-VI cases accounted for 1.9% (2/105). Patients were followed up for more than one year, with excellent facial nerve function retention rate (H-B I-II level) was 74.4% (58/78). Conclusion : Acoustic neuroma patients after surgery, the long-term (${\geq}1year$) facial nerve function excellent retaining rate was closely related with surgical proficiency, post-operative immediate facial nerve function, diameter of tumor and whether to use electrophysiological monitoring techniques; while there was no significant correlation with the patient's age, surgical approach, whether to stripping the internal auditory canal, whether there was cystic degeneration, tumor recurrence, whether to merge with obstructive hydrocephalus and the length of the duration of symptoms.

Anchoring effect of Ni²⁺ in stabilizing reduced metallic particles for growing single-walled carbon nanotubes

He, Maoshuai,Wang, Xiao,Zhang, Lili,Wu, Qianru,Song, Xiaojie,Chernov, Alexander I.,Fedotov, Pavel V.,Obraztsova, Elena D.,Sainio, Jani,Jiang, Hua,Cui, Hongzhi,Ding, Feng,Kauppinen, Esko Elsevier 2018 Carbon Vol.128 No.-

<P><B>Abstract</B></P> <P>The suitability of the NiMgO catalyst as a catalyst in chiral-selective growth of single-walled carbon nanotubes (SWNTs) by chemical vapor deposition has been assessed. It reveals that catalyst calcination temperature plays an important role in affecting the catalyst performances. Using CO as the carbon precursor and a chemical vapor deposition reaction temperature of 600 °C, NiMgO pre-calcined at 600 °C demonstrates the best performances in catalyzing the growth of SWNTs with predominant (6, 5) species. Systematic characterizations on catalysts calcinated at different temperatures indicate that Ni<SUP>2+</SUP> ions diffuse towards the interior of MgO matrix upon annealing. DFT-based calculations reveal that the binding energy between Ni<SUP>2+</SUP> and adjacent Ni(0) is larger than that between Mg<SUP>2+</SUP> and Ni (0), while Ni<SUP>2+</SUP> situated deep inside MgO has weak interactions with surface Ni atoms. This work highlights the importance of subsurface Ni<SUP>2+</SUP> in anchoring reduced surface Ni atom, which inhibits the aggregation of Ni particles and therefore, facilitates the growth of SWNTs with a narrow chirality distribution.</P> <P><B>Graphical abstract</B></P> <P>A Ni-incorporated MgO catalyst was developed for predominant synthesis of (6, 5) single walled carbon nanotubes. Density functional theory-based calculations revealed that the unreduced subsurface Ni stabilized reduced Ni atoms on the surface, facilitating the growth of carbon nanotubes with a narrow chirality distribution.</P> <P>[DISPLAY OMISSION]</P>