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Defence Technology（防务技术） 2024年第2期32卷 675-690页

作者： Xijin Wang Zhitao Liu Pengfei Sun Feiyun Chen Bin Xu xin liao School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina China North Industries Group Corporation Limited Beijing 100045China

The severe erosion and inadequate mechanical strength are prominent challenges for high-energy gun propellants.To address it,novel PTW@PDA composites was prepared by polydopamine(PDA)-modifying onto potassium titanate whisker(PTW,K_(2)Ti_(6)O_(13)),and after was incorporated into gun propellant as erosion-reducing and mechanical-reinforcing fillers.The interfacial characterizations results indicated that as-prepared PTW@PDA composites exhibits an enhanced surface compatible with propellant matrix,thereby facilitating their dispersion into propellants more effectively than raw PTW materials.Compared to original propellants,PTW@PDA-modified propellants exhibited significant less erosion,with a Ti-Kbased protective coating being detected on the eroded steel.And 0.5 wt%and 1.0 wt%addition of PTW@PDA significantly improved impact,compressive and tensile strength of propellants.Despite the inevitably reduction in relative force,PTW@PDA slightly increase propellant burning rate while exerting little adverse impact on propellant dynamic activity.This strategy can provide a promising alternative to develop high-energy gun propellant with less erosion and more mechanical strength.

关键词： High energy gun propellant Potassium titanate whiskers Polydopamine modification Erosion inhibitors Mechanical reinforcing fillers

Polyp-Canal Reconstruction Reveals Evolution Toward Complexity in Corals

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Research 2024年第1期2023卷 417-428页

作者： Yixin Li xin liao xin Wang Yuanchao Li Hongwei Zhao Yunpeng Zhao Junyuan Chen Chunpeng He Zuhong Lu State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Guangxi Key Lab of Mangrove Conservation and Utilization Guangxi Mangrove Research CenterGuangxi Academy of SciencesBeihai 536000China Hainan Academy of Ocean and Fishery Sciences Haikou 571126China State Key Laboratory of Marine Resources Utilization in South China Sea Hainan UniversityHaikou 570228China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences39 East Beijing RoadNanjing 210008China

Modern scleractinian corals are classified into robust,complex,and basal clades through comparative molecular studies.However,only few morphological or biological criteria can systematically determine the evolutionary trajectories of these major scleractinian coral clades.Here,we obtained the structural information of 21 scleractinian coral species representing robust and complex clades:High-resolution micro-computed tomography was used to reconstruct the polyp-canal systems in their colonies and to visualize the dynamic polyp growth processes.We found that the emergence of mesh-like canals may distinguish representatives of complex and robust clades.The differences in polyp-canal connections suggest distinct evolutionary trajectories among coral species:The formation of the canal network promoted the development of more complex coral structures,and coral polyps within this network formed calices of very similar volume,following precise axial growth directions.The influence of individual polyps on the coral colony becomes less significant as coral structures become more complex,and coral species with more complicated polyp-canal systems occupied niches more efficiently.This work supplements current evolutionary studies on reef-building corals,providing insight for further studies on coral growth patterns.

关键词： Coral representing directions

Multiplicity of solutions for the semilinear subelliptic Dirichlet problem

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Science China Mathematics 2024年第3期67卷 475-504页

作者： Hua Chen Hong-Ge Chen Jin-Ning Li xin liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈C(Ω×R),g(x,u)is a Carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth boundary.Combining the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the Morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem above.Furthermore,we discuss the difference between the eigenvalue estimate approach and the Morse index approach in degenerate situations.Compared with the classical elliptic cases,both approaches here have their own strengths in the degenerate cases.This new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method Morse index

Effects of particle size and content of RDX on burning stability of RDXbased propellants

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Defence Technology（防务技术） 2022年第7期18卷 1247-1256页

作者： Bin-bin Wang xin liao Luigi T.DeLuca Wei-dong He School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Special Energy Materials Ministry of EducationNanjing210094China SPLab Department of Aerospace EngineeringPolitecnico di Milano(RET)MilanI-20156Italy

Particle size and content of RDX are the two main factors that affect the burning stability of RDX-based propellants. However, these effects and the corresponding mechanisms are still controversial. In this work, we investigated the physicochemical processes during burning and the corresponding mechanisms through the technologies of structure compactness analysis on the base of voidage measurement and theoretical interfacial area estimation, apparent burning rate measurement using closed vessel(CV)and extinguished burning surface characterization relying on interrupted closed vessel(ICV) and scanning electron microscope(SEM). The results indicate that the voidage increased with the increase of RDX content and particle size due to the increasing interfacial area and increasing interface gap size,respectively. The apparent burning rate increased with the increase of RDX particle size because of the decreasing RDX specific surface area on the burning surface, which could decrease the heat absorbing rates of the melting and evaporation processes of RDX in the condensed phase. Similarly, the apparent burning rate decreased with the increase of RDX content at pressures lower than around 55 MPa due to the increasing RDX specific surface area. Whereas, an opposite trend could be observed at pressures higher than around 55 MPa, which was attributed to the increasing heat feedback from the gas phase as the result of the increasing propellant energy. For propellants containing very coarse RDX particles, such as 97.8 and 199.4 μm average size, the apparent burning rate increased stably with a flat extinguished surface at pressures lower than around 30 MPa, while increased sharply above around 30 MPa with the extinguished surface becoming more and more rugged as the pressure increased. In addition, the turning degree of u-p curve increased with the increase of coarse RDX content and particle size, and could be reduced by improving the structure compactness.

关键词： RDX particle Size and content Structure compactness Apparent burning rate Extinguished surface Burning stability

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延展认知与功能主义的关系初探

科学技术哲学研究 2024年第3期41卷 21-27页

作者：廖新媛北京大学哲学系北京100871

延展认知理论主张大脑之外的因素可以部分地构成人们的心理状态。为了论证这一点,它的支持者提出了“对等性原则”,即应该给予发挥了相同作用的外部过程和内部过程同等的认知地位。然而,延展认知的批评者则不断指出内外过程的差异,质疑... 详细信息

延展认知理论主张大脑之外的因素可以部分地构成人们的心理状态。为了论证这一点,它的支持者提出了“对等性原则”,即应该给予发挥了相同作用的外部过程和内部过程同等的认知地位。然而,延展认知的批评者则不断指出内外过程的差异,质疑“对等性原则”的有效性。面对这些挑战,部分支持者借用功能主义来说明“对等性原则”要求的是“功能对等性”,而不必在意内外因素之间的表面差异。但是这种方式也引发了新一轮的质疑。文章认为,延展认知与功能主义可以分开看待,延展认知在没有功能主义支持的情况下仍旧成立。

关键词：延展认知功能主义多重可实现性对等性原则

Experimental model of Fusarium solani keratitis in rats

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International Journal of Ophthalmology(English edition) 2011年第4期4卷 371-376页

作者： Jiang-Li Zhu, xin liao People's Hospital Affiliated to Tongji University School of Medicine Shanghai 200072 China People's Hospital Affiliated to Shanghai Jiaotong University School of Medicine Shanghai 200011 China Department of Ophthalmology Shanghai East Hospital Affiliated to Tongji University School of Medicine Shanghai 200120 China

AIM: To establish a repeatable rat model of Fusarium solani keratitis (F. solani keratitis) that mimicked fungal keratitis in humans. METHODS: Wistar rats' corneas were scratched on the superficial stroma after scraping the unilateral corneal epithelia. Then, the corneal surface was inoculated with different inoculum dose of E solanispore suspension. Doses ranged from 10(6) to 10(9) colony-forming unit per milliliter (CFU/mL). The treated corneas were covered by contact lenses that were made of Parafilm M membrane. Negative controls were inoculated with sterile phosphate-buffered saline (PBS). For statistical analysis, corneas were evaluated daily on a 12-point scale to check the state of corneal inflammation. Furthermore, the pathological characteristics of this model were investigated. RESULTS: The rat model of F solani keratitis was established by the combination methods of corneal trauma and parafilm-made contact lens and inoculation of fungus spore suspension. 10(6) and 10(7)CFU/mL of F solani induced mild corneal infection, while 10(8)CFU/mL of F solani was sufficient to induce moderate infection that was consistent with human keratomycosis. Dose of 10(9)CFU/mL of E solani was excessive and led to perforated corneas. CONCLUSION: The rat model of E solani keratitis, established by the combinational methods of corneal trauma, parafilm-made contact lens and the appropriate dose of inoculum, that imitates the developing processes of F solani keratitis in human beings and provides a repeatable method of creating a rat model.

关键词： fungal keratitis Fusarium solani corneal trauma contact lens rat

A new streamline diffusion finite element method for the generalized Oseen problem

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Applied Mathematics and Mechanics(English Edition) 2018年第2期39卷 291-304页

作者： Chao XU Dongyang SHI xin liao Faculty of Mathematics and Physics Education Luoyang Institute of Science and Technology School of Mathematics and Statistics Zhengzhou University

This paper aims to present a new streamline diffusion method with low order rectangular Bernardi-Raugel elements to solve the generalized Oseen equations. With the help of the Bramble-Hilbert lemma, the optimal errors of the velocity and pressure are estimated, which are independent of the considered parameter e. With an interpolation postprocessing approach, the superconvergent error of the pressure is obtained. Finally, a numerical experiment is carried out to confirm the theoretical results.

关键词： streamline diffusion method Bernardi-Raugel element Oseen problem,superconvergent error estimate

Low order nonconforming mixed finite element method for nonstationary incompressible Navier-Stokes equations

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 1095-1112页

作者： Chao XU Dongyang SHI xin liao Faculty of Mathematics and Physics Education Luoyang Institute of Science and Technology School of Mathematics and Statistics Zhengzhou University

This paper studies a low order mixed finite element method （FEM） for nonstationary incompressible Navier-Stokes equations. The velocity and pressure are approximated by the nonconforming constrained Q1^4ot element and the piecewise constant, respectively. The superconvergent error estimates of the velocity in the broken H^1-norm and the pressure in the L^2-norm are obtained respectively when the exact solutions are reasonably smooth. A numerical experiment is carried out to confirm the theoretical results.

关键词： nonstationary incompressible Navier-Stokes equation constrained Q1^rot nonconforming finite element （FE） superconvergent error estimate

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基于JPEG图像的模块化可逆信息隐藏方法

计算机应用研究 2024年第4期41卷 1177-1183页

作者：张成欧博廖鑫湖南大学信息科学与工程学院长沙410082

当前的可逆信息隐藏方法为了寻求更好的嵌入性能,通常会基于给定的图像内容对修改模式和嵌入参数作出自适应的调整。然而,通过细化自适应程度或扩大解空间来寻找更优解时,会造成计算复杂度高、时间成本难以承受等问题。为此,提出了一种... 详细信息

当前的可逆信息隐藏方法为了寻求更好的嵌入性能,通常会基于给定的图像内容对修改模式和嵌入参数作出自适应的调整。然而,通过细化自适应程度或扩大解空间来寻找更优解时,会造成计算复杂度高、时间成本难以承受等问题。为此,提出了一种适用于JPEG图像的模块化可逆嵌入方法来提高自适应寻优的效率。通过比较不同情况下最优解的嵌入性能,对原有的解空间进行优化、筛选,从而生成一个适用于不同图像的通用修改模式集合。每一个修改模式被定义为在多直方图修改框架下的最优嵌入点集合。在嵌入时,为给定的图像内容自适应地从预设的解集中选定合适的修改模式。实验在USC-SIPI数据集上与五个具有代表性的方法进行了比较。相比于同类算法,所提算法可将峰值信噪比提升0.03~1.81 dB。对于文件大小扩展,所提算法的性能结果可比两个经典方法分别减少12.4%和5.1%。实验结果表明,相比于主流经典方法,该方法在含密图像质量和文件大小扩展方面有更好的性能表现,并能以较低的计算复杂度取得与最近的高效方法相近的自适应嵌入效果。

关键词：可逆信息隐藏 JPEG图像模块式优化自适应修改时间复杂度

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多囊卵巢综合征与代谢异常

中华糖尿病杂志 2024年第3期16卷 371-376页

作者：廖鑫黄琦张琳王茜遵义医科大学附属医院内分泌与代谢病科遵义563000 遵义医科大学附属医院核医学科遵义563000

多囊卵巢综合征(PCOS)是育龄妇女最常见内分泌疾病之一,PCOS患者大多存在糖脂代谢异常,同时高血压、脂肪肝以及心血管疾病的发生风险显著增加。因此,PCOS患者除了关注生殖异常,更需要关注代谢异常。所有PCOS患者就诊时均应评估是否存在... 详细信息

多囊卵巢综合征(PCOS)是育龄妇女最常见内分泌疾病之一,PCOS患者大多存在糖脂代谢异常,同时高血压、脂肪肝以及心血管疾病的发生风险显著增加。因此,PCOS患者除了关注生殖异常,更需要关注代谢异常。所有PCOS患者就诊时均应评估是否存在代谢异常,尤其是糖代谢。生活方式的干预和管理是改善PCOS患者代谢异常最基础、最重要的非药物措施。药物治疗中,二甲双胍、噻唑烷二酮类以及α-葡萄糖苷酶抑制剂等药物治疗在多个指南中有相应的推荐,近年来的文献报道,新型降糖药物胰高糖素样肽-1受体激动剂及钠-葡萄糖共转运蛋白2抑制剂也有改善PCOS女性代谢异常的作用。

关键词：多囊卵巢综合征雄激素增多症代谢异常胰岛素抵抗