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Stability switches and bifurcation analysis in a coupled neural system with multiple delays

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Science China(Technological Sciences) 2016年第6期59卷 920-931页

作者： ge Ju hong XU Jian Department of Mathematics and Information Science Henan University of Economics and Law School of Aerospace Engineering and Applied Mechanics Tongji University

A coupled neural system with multiple delays has been investigated. The number of equilibrium points is analyzed. It implies that the neural system exhibits a unique equilibrium and three ones for the different values of coupling weight by employing the pitchfork bifurcation of the trivial equilibrium point. Further, the local asymptotical stability of the trivial equilibrium point is studied by analyzing the corresponding characteristic equation. Some stability criteria involving multiple delays and coupling weight are obtained. The results show that the neural system exhibits the delay-independent and delay-dependent stability. Increasing delay induces stability switching between resting state and periodic motion in some parameter regions of coupling weight. In addition, the criterion for the global stability of the trivial equilibrium is also derived by constructing a suitable Lyapunov functional. Finally, some numerical simulations are taken to support the theoretical results.

关键词： multiple delays stability switches global stability

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疝修复补片:材料设计与应用的最新进展

中国组织工程研究 2025年第16期29卷 3494-3502页

作者：陈静宇洪阁郭宁刘天军天津中医药大学天津市301617 中国医学科学院北京协和医学院生物医学工程研究所天津市生物医学材料重点实验室天津市300192 河北大学基础医学院河北省保定市071000

背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”... 详细信息

背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”为中文检索词,以“abdominal wall defect,hernia patches,hernia treatment”为英文检索词,分别检索中国知网、谷歌学术和PubMed数据库,检索时限主要为2018年1月至2024年2月,同时采用少数经典的早期文献以概述疝修复补片的发展历程,通过阅读题目和摘要进行初步筛选,排除与疝修复材料相关性较低的文献,最终纳入90篇文献进行归纳总结。结果与结论:根据制备材料的不同可以将疝修复补片分为不可吸收人工合成补片、可吸收人工合成补片、天然高分子补片和复合补片。不可吸收补片具有较高的机械强度,有益于疝气区域的组织愈合,但体内长期存在的补片可能会引发身体的免疫反应,导致炎症和疼痛。可吸收人工合成补片与天然高分子补片具有良好的组织相容性、降解性,但机械强度不稳定。复合材料补片继承了传统不可吸收补片优良的机械性能,同时通过可吸收部分的设计降低了一些并发症发生的风险。在疝修复补片的后续研究中,科研人员应重点关注如何将新技术与复合补片结合起来,形成多功能的疝修复补片。

关键词：腹壁缺损疝修复补片聚丙烯抗菌补片疝气不可吸收补片可吸收补片复合补片

Electronic Properties of Armchair Graphene Nanoribbons with Oxygenterminated Edges:A Density Functional Study

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Chinese Journal of Structural Chemistry 2015年第5期34卷 641-649页

作者： ge hong-Yu WANG Guo Department of Chemistry Capital Normal University

Armchair graphene nanoribbons with different proportions of edge oxygen atoms are analyzed in this study using the crystal orbital method,which is based on density functional *** buckled edges are present,all the nanoribbons are energetically *** the adjacent edge oxygen atoms,the isolated edge oxygen atoms cause semiconductor-metal transitions by introducing edge *** graphene nanoribbons with all oxygen atoms on the edges,band gap and carrier mobility vary with ribbon ***,this behavior is different from that of hydrogen-passivated graphene nanoribbons because of different effective widths,which are pictorially presented with crystal *** carrier mobilities are as 18%~65% magnitude as those of hydrogen-passivated nanoribbons and are of the order of 10^3 cm^2·V^-1·s^-1.

关键词： graphene nanoribbon semiconductor-metal transition crystal orbital carrier mobility density functional theory

A Prediction Model of MF Radiation in Environmental Assessment

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Biomedical and Environmental Sciences 2006年第5期19卷 405-408页

作者： HE-SHAN ge YAN-FENG hong Institute for Environmental Health and Related Product Safety China CDC Beijing 100050 China

Objective To predict the impact of MF radiation on human health. Methods The vertical distribution of field intensity was estimated by analogism on the basis of measured values from simulation measurement. Results A kind of analogism on the basis of geometric proportion decay pattern is put forward in the essay. It showed that with increasing of height the field intensity increased according to geometric proportion law. Conclusion This geometric proportion prediction model can be used to estimate the impact of MF radiation on inhabited environment, and can act as a reference pattern in predicting the environmental impact level of MF radiation.

关键词： MF radiation Electromagnetic environment Predictive model Environmental impact assessment

Synthesis,Crystal Structure and Fluorescence Property of the Ag(Ⅰ) Coordination Polymer Constructed by 2D[Ag(1,3-BIP)(PMA)_(0.5)]_n^(n-)Layers and 1D[Ag(1,3-BIP)(H_2O)]_n^(n+) Chains

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1259-1264页

作者： LU Jiu-Fu ge hong-Guang SHI Juan Chemical Engineering College Shaanxi University of Technology

A new AgO） coordination polymer, {[Ag（1,3-BIP）（H20）][Ag（1,3- BIP）（PMA）0.5.- 4H20}n （PMA = 1,2,4,5-benzenetricarboxylic acid, 1,3-BIP = 1,3-bis（imidazole）propane）, have been synthesized and characterized by single-crystal X-ray diffraction, powder XRD, FTIR, TGA and elemental analysis techniques. The single-crystal X-ray diffraction reveals that the title complex is formed by 1D polymeric cationic chains of [Ag（1,3-BIP）（H2O）]n^n＋ and 2D polymetric anionic layer of [Ag（1,3-BIP）（PMA）0.5]n^n-, which are further linked by intermolecular H-bonding to form a 3D supramolecular framework. In addition, the photoluminescence property of the title complex in the solid state at room temperature was also investigated.

关键词： Ag(I) coordination polymer, helical chains, photoluminescence property

Brownian Dynamics Simulations of Rigid Polyelectrolyte Chains Grafting to Spherical Colloid

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Chinese Journal of Polymer Science 2018年第6期36卷 791-798页

作者： Qing-Hai Hao Zhen Zheng Gang Xia hong-ge Tan College of Science Civil Aviation University of China

Brownian dynamics simulations are employed to explore the effects of chain stiffness and trivalent salt concentration on the conformational behavior of spherical polyelectrolyte brush. The rigid brush adopts bundle-like morphology at a wide range of trivalent salt concentration. The number variation of bundles pinned on the colloid surface shows a non-monotonic profile as a function of the chain stiffness. The radial distributions of monomers and ions and the charge ratio between condensed ions and monomers are calculated. The charge inversion is observed for the high salt concentration regardless of chain rigidity. Furthermore, the pair correlation functions of monomer-monomer and monomer-salt cation are used to elucidate the aggregated mechanism of the bundle-like structure.

关键词： Brownian dynamics simulation Spherical polyelectrolyte brush Chain stiffness Trivalent salt concentration Pinned bundle morphology

Mechanism of Strength Improvement of Magnetite Pellet by Adding Boron-bearing Iron Concentrate

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Journal of Iron and Steel Research International 2014年第1期21卷 9-15页

作者： hong-wei GUO Jun-li BAI Jian-liang ZHANG hong-ge LI School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The mechanism of improving compressive strength of magnetite pellet by adding boron-bearing iron concentrate was studied. Boron-bearing iron concentrate and magnetite were mixed, pelletized and roasted under differ ent roasting conditions. Then, compressive strength of pellets was tested, and polished sections of the roasted pellets were analyzed from the perspective of mineralogy. Finally, the effects of different proportions, roasting temperatures and roasting time of boron-bearing iron concentrate on the compressive strength of magnetite pellets were investigated and explained.

关键词： boron-bearing iron concentrate magnetite pellet compressive strength roasting condition proportion

Relationship between expression of COX-2,TNF-α,IL-6 and autoimmune-type recurrent miscarriage

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Asian Pacific Journal of Tropical Medicine 2013年第12期6卷 990-994页

作者： Fu Hua Chang-Hua Li hong Wang hong-ge Xu Department of Gynaecology and Obstetrics Huai'an First People's HospitalNanjing Medical University

Objective:To investigate the roles of COX-2,TNF-α,IL-6 in the pathogenesis of autoimmunetype recurrent spontaneous abortion(RSA).Methods:RT-PCR was used to detect the mRNA of COX-2,TNF-α.IL-6 in the trophoblast cells of murine RSA and normal pregnant *** COX-2,TNF-α.IL-6 protein expressions were determined by using immunohistochemisry staining *** COX-2,TNF-α,IL-6 protein expressions were determined by ***:The embryo loss rates in experiment group was significantly higher than that in normal pregnancy control group,the expression of COX-2,TNF-α,IL-6 in the trophoblast cells of murine RSA and normal pregnant *** expression of COX-2 in autoimmunetype recurrent spontaneous abortion was significantly lesser than in normal pregnant *** expression of TNF-α,IL-6 in autoimmune-type recurrent spontaneous abortion was significantly higher than in normal pregnant *** was a positively correlation between TNF-αand *** was no relationship between COX-2,TNF-αand ***:The abnormal expression of COX-2,TNF-αand IL-6 may result in RSA.

关键词： Autoimmune Recurrent miscarriage Animal model Maternal-fetal interface

Application of a Novel Multilayer Spray Forming Technology in the Preparation of Large Dimension Aluminium Alloy Blanks

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Journal of Central South University 2000年第4期12卷 201-204页

作者： CHEN Zhen-hua KANG Zhi-tao YAN hong-ge Department of Materials Science and Engineering Central South UniversityChangsha 410083China

Principle of multilayer spray forming and preparation technique of tubes and billets by it were presented and described in the article. The marked characteristic of multilayer spray forming technology is the to and fro movement of spray system, so the preform is deposited layer by layer with the surface of the deposit retaining relatively low temperature during the spray forming process. The two outstanding advantages of multilayer spray forming are as follows: suitable for manufacturing large dimension blanks, higher solidification cooling rate. Now Al Fe V Si alloy (8009) and SiC particle reinforced aluminium alloy metal matrix composite billets of 300 600 mm in diameter and tubular blanks of size up to 650 mm in outer diameter, 360 mm in inner diameter and 1 200 mm in length have been made with the technology. After extrusion, the material has good properties.

关键词： multilayer spray forming billet tube aluminium alloy composite