Synthesis and Characterization of Novel Homopolyimides Containing Pyridine and Morpholine Groups for Gas Separation by Molecular Design and Simulation

Jing Ni,Jinling Li,Bowen Wei,Yufei Shi,Chanjuan Liu,Li Zhou,Xiaohua Huang 한국섬유공학회 2023 Fibers and polymers Vol.24 No.12

A novel 4-(4-(1-morpholinyl)phenyl)-2,6-bis(4-aminophenyl)pyridine (MPAP) diamine monomer was designed and synthesized by introducing non-coplanar morpholine groups and pyridine heterocyclic structures. By one-step homopolymerization of MPAP and different dianhydrides, three new polyimides (PIs) were synthesized. The obtained PIs are easily soluble in common organic solvents, such as NMP, DMAc, and CHCl3. Simultaneously, PIs have high thermal performance (Tg = 277–377 °C) and excellent thermal stability (Td,5% and Td,10% are 460–487 °C and 525–545 °C). They also have good optical transparency (λcutoff = 380–394 nm, λ80% = 469–482 nm) and hydrophobicity (θ = 87–92º). The free volume and gas adsorption are simulated by Materials Studio 2019 software, and the simulation results match the gas separation performance obtained from experimental test. They show good gas separation performance as well, especially PI-3 for the CO2/N2 (up to 23.26), O2/N2 (up to 5.02) and He/N2 (up to 59.78) separations, which is close to the 1991 Robeson upper bound.

Metal-Doped In2O3 Nanosphere Arrays with Enhanced Gas-Sensing Property

Xuanji Zhang,Ni Deng,Xianjia Chen,Yanting Yang,Jing Li,BO HONG,DINGFENG JIN,Xiaoling Peng,XINQING WANG,Hongliang Ge,HONGXIAO JIN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.3

In2O3 and metal-doped (Ni or Ce) In2O3 mesoporous three-dimensional (3D) nanospheres arrays were synthesized via nanocasting using mesoporous silica as hard templates. Effects of Ni or Ce doping on the structure, optical and gas-sensing properties of the In2O3 nanospheres were investigated. Both the undoped and the doped In2O3 nanospheres showed single-phase structure without any impurity. The nanospheres were about 20 nm in size and they stacked closely to formrigid 3D mesoporous structure. Achange in the value of optical band gap was observed upon metal doping. The room temperature photo luminescence behavior also showed some differences between pure and doped In2O3. Compared with pure In2O3 nanospheres, the metal-doped In2O3 exhibited superior response, fast recovery and good selectivity to ethanol. The enhanced gas-sensing properties might be related to the doping of metal ion and its effective contribution towards the oxygen vacancies, conductivity and crystallite size of the grains.

The Inhibition Effect of Triptolide on Human Endometrial Carcinoma Cell Line HEC-1B: a in vitro and in vivo Studies

Ni, Jing,Wu, Qiang,Sun, Zhi-Hua,Zhong, Jian,Cai, Yu,Huang, Xin-En Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: To investigate the inhibitory effect and the underlying mechanism of triptolide on cultured human endometrial carcinoma HEC-1B cells and corresponding xenograft. Materials and Methods: For in vitro studies, the inhibition effect of proliferation on HEC-1B cell by triptolide was determined by MTT assay; cell cycle and apoptosis of the triptolide-treated and untreated cells were detected by flow cytometry. For in vivo studies, a xenograft tumor model of human endometrial carcinoma was established using HEC-1B cells, then the tumor-bearing mice were treated with high, medium, and low-dose ($8{\mu}g$, $4{\mu}g$ and $2{\mu}g/day$) triptolide or cisplatin at $40{\mu}g/day$ or normal saline as control. The mice were treated for 10-15 days, during which body weight of the mice and volume of the xenograft were weighted. Then expression of Bcl-2 and vascular endothelial growth factor (VEGF) was analyzed by SABC immunohistochemistry. Results: Cell growth was significantly inhibited by triptolide as observed by an inverted phase contrast microscope; the results of MTT assay indicated that triptolide inhibits HEC-1B cell proliferation in a dose and time-dependent manner; flow cytometry showed that low concentration (5 ng/ml) of triptolide induces cell cycle arrest of HEC-1B cells mainly at S phase, while higher concentration (40 or 80 ng/ml) induced cell cycle arrest of HEC-1B cells mainly at G2/M phase, and apoptosis of the cells was also induced. High-dose triptolide showed a similar tumor-inhibitory effect as cisplatin (-50%); high-dose triptolide significantly inhibited Bcl-2 and VEGF expression in the xenograft model compared to normal saline control (P<0.05). Conclusions: triptolide inhibits HEC-1B cell growth both in vitro and in mouse xenograft model. Cell cycle of the tumor cells was arrested at S and G2/M phase, and the mechanism may involve induction of tumor cell apoptosis and inhibition of tumor angiogenesis.

Postmenopausal Hormone Therapy is Associated with in Situ Breast Cancer Risk

Ni, Xiao-Jian,Xia, Tian-Song,Zhao, Ying-Chun,Ma, Jing-Jing,Zhao, Jie,Liu, Xiao-An,Ding, Qiang,Zha, Xiao-Ming,Wang, Shui Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background: The relationship between postmenopausal hormone therapy (HT) and invasive breast cancer has been extensively investigated, but that with breast carcinoma in situ (BCIS) has received relatively little attention. The aim of our present study was to review and summarize the evidence provided by longitudinal studies on the association between postmenopausal HT use and BCIS risk. Methods: A comprehensive literature search for articles published up to May 2012 was performed. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Relative risk (RR) or odds ratio (OR) values were calculated using 14 reports (8 case-control studies and 6 cohort studies), published between 1986 and 2012. Results: There was evidence of an association between ever postmenopausal estrogen use and BCIS based on a random-effects model (RR = 1.25, 95% confidence interval (CI) = 1.01, 1.55). However, we found no strong evidence of an association between ever postmenopausal estrogen combined with progesterone use and BCIS using a randomeffects model (RR = 1.55, 95% CI = 0.95, 2.51). Furthermore, our analysis showed a strong association between "> 5 years duration" of estrogen or estrogen combined with progesterone use and BCIS. Furthermore, current use of any HT is associated with increased risk of BCIS in cohort studies. Additional well-designed large studies are now required to validate this association in different populations.

Droplet transient migration and dynamic force balance mechanism on vibration-controlled micro-texture surfaces

Jing Xu,Guodong Liu,Jiadi Lian,Jing Ni,Jing Xiao 한국물리학회 2018 Current Applied Physics Vol.18 No.11

In this paper, forced vibration was used to regulate the droplet migration, fully recording the transient migration of droplets on a micro-textured substrate under the resonance frequency by a high-speed camera. The influence of resonance frequency and dynamic migration characteristics of droplets on the solid micro-texture surface under lateral vibration were researched. The experiment demonstrates that the driving force is caused by the difference between the left and right contact angles made the droplet oscillate and migrate, and as time t increases, the left and right contact points are periodically shifted and the amplitude of migration increases. Therefore, based on the droplet migration behavior and its force balance mechanism, a spring vibration model of migration behavior of the vibrating droplet micro unit was set up to predict the complete trajectory of its migration on a solid surface. The calculation results show that the theoretical displacement is less than the experimental displacement, and the longer the time, the larger the difference. Affected by the vibration, part of the droplet permeates through the micro-texture, resulting in the droplet losing height and the contact angle becoming smaller as well. While the other part of droplet overcomes the internal surface tension to migrate.

Knock-out Rice Xylanase Inhibitor Gene (OsXII)Showed Abnormal Plant Development and Conferred Resistance to the Rice Blast Fungus

Jing Ni Wu,Yi Ming Wang,Sun Tae Kim,Kyu Young Kang 한국응용생명화학회 2008 Applied Biological Chemistry (Appl Biol Chem) Vol.51 No.5

Modeling and Tracing Web Content Provenance

Jing Ni,Jia Hao,Xuemei Li,Tong Zhao 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.4

In recent years, research in data provenance has attracted a lot of attention, since it helps to judge the relevance and trustworthiness of the information enclosed in the data. However, many webpages still lack provenance annotation, and this is a main obstacle of tracing the content. In this paper, we propose a model for on-line Web paper variation, based on the W3C PROV Data Model. A semantic similarity clustering method is adopted to determine the relationship within the documents derivation, and feature words variation and the responsible person can be found with the aid of PROV-O. To verify this model, a detailed case study is shown in this paper.

Design Feature-Based Jetfighter Shape Modeling

Jing Zang,Tianping Liu,Xianping Ni 한국항공우주학회 2013 International Journal of Aeronautical and Space Sc Vol.14 No.3

A jetfighter shape modeling method based on design features is researched, to improve the efficiency of shape modeling in the stage of conceptual aircraft design. The aircraft’s general design features and shape parameters, including geometric and position parameters, are described. The coordinate systems of the entire aircraft and its components are defined. As a sample of local shape, a method of inlet intake modeling is introduced. The whole process of the modeling method is proposed. Three examples of different jetfighters are listed, to describe the achievement of basic layout, which includes four main elements. The Fusion of Components can be achieved by regulating the details of the sections of the fuselage. Sample Cases of typical layouts are shown to verify the effectiveness of the proposed method, which provides the basis for further analysis and optimization.

Graphene–Ferroelectric Hybrid Structure for Flexible Transparent Electrodes

Ni, Guang-Xin,Zheng, Yi,Bae, Sukang,Tan, Chin Yaw,Kahya, Orhan,Wu, Jing,Hong, Byung Hee,Yao, Kui,Ö,zyilmaz, Barbaros American Chemical Society 2012 ACS NANO Vol.6 No.5

<P>Graphene has exceptional optical, mechanical, and electrical properties, making it an emerging material for novel optoelectronics, photonics, and flexible transparent electrode applications. However, the relatively high sheet resistance of graphene is a major constraint for many of these applications. Here we propose a new approach to achieve low sheet resistance in large-scale CVD monolayer graphene using nonvolatile ferroelectric polymer gating. In this hybrid structure, large-scale graphene is heavily doped up to 3 × 10<SUP>13</SUP> cm<SUP>–2</SUP> by nonvolatile ferroelectric dipoles, yielding a low sheet resistance of 120 Ω/□ at ambient conditions. The graphene–ferroelectric transparent conductors (GFeTCs) exhibit more than 95% transmittance from the visible to the near-infrared range owing to the highly transparent nature of the ferroelectric polymer. Together with its excellent mechanical flexibility, chemical inertness, and the simple fabrication process of ferroelectric polymers, the proposed GFeTCs represent a new route toward large-scale graphene-based transparent electrodes and optoelectronics.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-5/nn3010137/production/images/medium/nn-2012-010137_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn3010137'>ACS Electronic Supporting Info</A></P>

Parametric Study of Water Inrush in a Tunnel Crossing a Fault based on the “Three Zones” fault structure

Jing Wu,Xintong Wang,Li Wu,Ya-ni Lu,Yanhua Han 대한토목학회 2022 KSCE Journal of Civil Engineering Vol.26 No.8

As tunnelling progresses into the complex geological environment such as fault zones, water inrush has become one of the main geological hazards during tunnel construction. Consequently, understanding the evolution of pore pressure and flow velocity when a tunnel is excavated in a fault zone is crucial to ensure safe working conditions and reduce construction risks. In this work, based on the concept of “Three Zones” fault structure, we simulate the nonlinear water inrush process by solving the Darcy-Brinkman flow equation for the host rock and the fault zone. We examine the impacts of 1) the angle between the tunnelling direction and the fault and 2) the relative position from the tunnel face to the fault on the evolution of pore pressure and flow velocity near the tunnel face. The results show that within 5 m to 20 m ahead of the working face, pore pressure, flow velocity, and water inrush rate are the smallest when the angle is 90°. As the angle decreases, both pore pressure and flow velocity ahead of the working face increase. The pore pressure is larger when the tunnel has not reached the fault zone than when the tunnel has crossed the fault zone. Flow velocity also exhibits similar behaviour as pore pressure. With different relative positions from the tunnel working face to the fault, the closer the tunnel face to the fault, the lower the pore pressure and the larger the flow velocity ahead of the tunnel face. The largest water inrush rate occurs when the tunnel face is excavated to the center of the fault core, and the water inrush rate declines as the distance away from the fault increases. The simulation results provided a new method for simulating water inrush when a tunnel crosses a fault and could provide valuable references for the prediction of water inrush for underground projects.