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Simulation of the plasticizing behavior of composite modified doublebase(CMDB)propellant in grooved calendar based on adaptive grid technology

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Defence Technology（防务技术） 2021年第6期17卷 1954-1966页

作者： Su-wei Wang Xiu-duo Song Zong-kai Wu Lei Xiao Guang-pu Zhang yu-bing hu ga-zi hao Wei Jiang Feng-qi Zhao National Special Superfine Powder Engineering Research Center of China School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094China Xi'an Modern Chemistry Research Institute Xi'an710065China

The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)*** of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering *** improve the accuracy of the simulation results,material parameters and model structure were corrected based on actual conditions,and adaptive grid technology was applied in the local mesh *** addition,the rheological behavior,motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps,rotational rates and temperatures of two *** results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the *** with the gap,the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear ***,under the synergistic effect of contact heat transfer as well as convective heat exchange,heat accumulated near the outlet and diffused along the reflux movement,which led to the countercurrent heat dissipation behavior of CMDB propellant *** plasticizing mechanism of slurry and the safety of calendering under different conditions were explored,which provided theoretical guidance and reference data for the optimization of calendering process *** on the simulation results,the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle.

关键词： Composite modified double base propellant Calendering process Fluid simulation Vortex flow0

参数优化最大二阶循环平稳盲解卷积行星轮轴承故障提取

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振动与冲击 2023年第2期42卷 321-328页

作者：林云郭瑜陈鑫昆明理工大学机电工程学院昆明650500

在行星齿轮箱振动中,齿轮相关振动分量通常具有较大的能量,同时轴承滑移会造成行星轮轴承故障对应振动分量的特征频率获取困难。为此,提出一种基于参数优化最大二阶循环平稳盲解卷积(cyclostationary blind deconvolution, CYCBD)的行... 详细信息

在行星齿轮箱振动中,齿轮相关振动分量通常具有较大的能量,同时轴承滑移会造成行星轮轴承故障对应振动分量的特征频率获取困难。为此,提出一种基于参数优化最大二阶循环平稳盲解卷积(cyclostationary blind deconvolution, CYCBD)的行星轮轴承故障提取方法。该方法针对CYCBD技术在轴承滑移条件下难以获取循环频率和滤波器长度的问题,以改进的包络谱故障特征比(improved envelope spectrum fault feature ratio, IFFR)指标作为粒子群算法的适应度函数,自动获取CYCBD算法中实际的循环频率和优化滤波器长度,利用参数自适应的CYCBD算法增强了轴承故障冲击。通过解卷积结果的平方包络谱反映轴承故障特征,达到准确提取故障特征的目的。故障仿真和试验研究结果表明,该方法可以有效提取行星轮轴承故障特征。

关键词：最大二阶循环平稳盲解卷积(CYCBD) 行星齿轮箱轴承故障诊断故障特征比

Non-invasive evaluation of liver steatosis with imaging modalities:New techniques and applications

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World Journal of gastroenterology 2023年第17期29卷 2534-2550页

作者： Ke-yu Zeng Wu-Yong-ga Bao Yun-han Wang Min Liao Jie Yang Jia-Yan huang Qiang Lu Department of Medical Ultrasound West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

In the world,nonalcoholic fatty liver disease(NAFLD)accounts for majority of diffuse hepatic ***,substantial liver fat accumulation can trigger and accelerate hepatic fibrosis,thus contributing to disease ***,the presence of NAFLD not only puts adverse influences for liver but is also associated with an increased risk of type 2 diabetes and cardiovascular ***,early detection and quantified measurement of hepatic fat content are of great *** biopsy is currently the most accurate method for the evaluation of hepatic ***,liver biopsy has several limitations,namely,its invasiveness,sampling error,high cost and moderate intraobserver and interobserver ***,various quantitative imaging techniques have been developed for the diagnosis and quantified measurement of hepatic fat content,including ultrasound-or magnetic resonancebased *** quantitative imaging techniques can provide objective continuous metrics associated with liver fat content and be recorded for comparison when patients receive check-ups to evaluate changes in liver fat content,which is useful for longitudinal *** this review,we introduce several imaging techniques and describe their diagnostic performance for the diagnosis and quantified measurement of hepatic fat content.

关键词： Non-alcoholic fatty liver disease hepatic steatosis Imaging techniques Quantitative evaluation Ultrasound Quantitative ultrasound

一种卷积神经网络和极限学习机相结合的人脸识别方法

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数据采集与处理 2016年第5期31卷 996-1003页

作者：余丹吴小俊江南大学物联网工程学院无锡214122

卷积神经网络是一种较好的特征提取器,但却不是最佳的分类器,而极限学习机能够很好地进行分类,却不能学习复杂的特征,根据这两者的优点和缺点,将它们结合起来,提出一种新的人脸识别方法。卷积神经网络提取人脸特征,极限学习机根据这些... 详细信息

卷积神经网络是一种较好的特征提取器,但却不是最佳的分类器,而极限学习机能够很好地进行分类,却不能学习复杂的特征,根据这两者的优点和缺点,将它们结合起来,提出一种新的人脸识别方法。卷积神经网络提取人脸特征,极限学习机根据这些特征进行识别。本文还提出固定卷积神经网络的部分卷积核以减少训练参数,从而提高识别精度的方法。在人脸库ORL和XM2VTS上进行测试的结果表明,本文的结合方法能有效提高人脸识别的识别率,而且固定部分卷积核的方式在训练样本少时具有较大优势。

关键词：卷积神经网络极限学习机特征提取人脸识别

Anti-MMP-2 and MMP-9 activity of Salsola komarovii Iljin extract and its solvent fractions

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Asian Pacific Journal of Tropical Biomedicine 2020年第10期10卷 460-469页

作者： Jung-ha Kil Fatih Karadeniz ga h.un yu hojun Kim Junse Kim Jung hwan Oh Jung Im Lee Chang-SukKong Youngwan Seo Marine Biotechnology Center for Pharmaceuticals and Foods Silla UniversityBaegyang-daero 700 beon-gil 140Sasang-guBusan 46958Korea Department of Food and Nutrition College of Medical and Life SciencesSilla UniversityBaegyang-daero 700 beon-gil 140Sasang-guBusan 46958Korea Division of Marine Bioscience Korea Maritime and Ocean UniversityBusan 49112Korea

Objective: To investigate matrix metalloproteinases(MMP)-2 and MMP-9 inhibitory effect of Salsola komarovii Iljin, an edible halophyte with health beneficial ***: Salsola komarovii crude extracts(SKI), and solvent(n-hexane, 85% aq. MeOh, n-BuOh, and h2O) fractionated extracts of SKI were prepared. Gelatin zymography was carried out to observe MMP enzymatic activity. The release of the MMP enzymes was measured by enzyme-linked immunosorbent assay. Expression of MMPs in m RNA and protein level were investigated by polymerase chain reaction analysis and immunoblotting, ***: SKI and SKI fractions inhibited active MMP-2 and MMP-9 amount in the treated cell culture medium. Also, SKI suppressed the release of MMP-2 and MMP-9 from stimulated hT1080 human fibrosarcoma cells. Furthermore, SKI suppressed the m RNA and protein expression of MMP-2 and MMP-9. SKI fractions showed parallel effects except for h2O fraction which did not yield any significant MMP inhibitory effect. Among fractions, 85% aq. Me Oh was the most active fraction to inhibit both the enzymatic effect and expression of MMP-2 and ***: SKI may contain potential MMP release inhibitory compounds. Salsola komarovii is a promising source of compounds against MMP and could be utilized in the development of antitumor agents.

关键词： release utilized effect

Puerariae Radix protects against ulcerative colitis in mice by inhibiting NLRP3 inflammasome activation

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Food Science and human Wellness 2024年第4期13卷 2266-2276页

作者： yu ga yuanyuan Wei Qingyu Zhao Yimeng Fan Yannan Zhang Zhifang Zhang Sijia hao Lixia Wang Zhifen Wang Jinlong han Shuang Wu Zhihui hao Innovation Centre of Chinese Veterinary Medicine College of Veterinary MedicineChina Agricultural UniversityBeijing 100086China National Center of Technology Innovation for Medicinal Function of Food National Food and Strategic Reserves AdministrationBeijing 100193China Inner Mongolia Medical university Hohhot 010059China China Agricultural university Yantai Institute Yantai 264670China Shandong Academy of Agricultural Sciences Jinan 250100China

Ulcerative colitis(UC)is a common inflammatory disease of the gastrointestinal *** Chinese medicine(TCM)has long been used in Asia as a treatment for UC and Puerariae Radix(PR)is a reliable anti-diarrheal *** aims of this study were to investigate the protective effect of PR using the dextran sulfate sodium salt(DSS)-induced UC model in mice and identify molecular mechanisms of PR *** chemical constituents of PR via ultra-performance liquid chromatography/tandem mass spectrometry and identified potential PR and UC targets using a network pharmacology(NP)approach were obtained to guide mouse experiments.A total of 180 peaks were identified from PR including 48 flavonoids,46 organic acids,14 amino acids,8 phenols,8 carbohydrates,7 alkaloids,6 coumarins and 43 other *** results showed that caspase-1 was the most dysregulated of the core genes associated with UC.A PR dose of 0.136 mg/g administered to DSS treated mice reversed weight loss and decreased colon lengths found in UC *** also alleviated intestinal mucosal shedding,inflammatory cell infiltration and mucin *** treatment suppressed upregulation of NOD-like receptor protein 3(NLRP3),cysteinyl aspartate-specific proteases-1(caspase-1),apoptosis-associated speck-like(ASC)and gasdermin D(GSDMD)at both the protein and m RNA expression *** addition of a small molecule dual-specificity phosphatase inhibitor NSC 95397 inhibited the positive effects of *** results indicated that PR exerts a protective effect on DSS-induced colitis by inhibiting NLRP3 inflammasome activation in mice.

关键词： Puerariae Radix Ulcerative colitis Molecular mechanisms Pyroptosis NOD-like receptor protein 3 inflammasome

On n-K Width of Certain Function Classes Defined by Linear Operators in L_2 Space

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Chinese Quarterly Journal of Mathematics 2016年第1期31卷 96-101页

作者： yu Rui-fang WU ga-ridi Department of Mathematics Inner Mongolia Normal University

Let M(u) be an N-function, L_r(f, x) and K_r(f, x) are Bak operator and Kantorovich operator, W_M(L_r(f)) and W_M(K_r(f)) are the Sobolev-Orlicz classes defined by L_r(f, x), K_r(f, x) and M(u). In this paper we give ... 详细信息

关键词： linear operator Sobolev-Orlicz class width

A review on the high energy oxidizer ammonium dinitramide:Its synthesis,thermal decomposition,hygroscopicity,and application in energetic materials

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Defence Technology（防务技术） 2023年第1期19卷 163-195页

作者： Fu-yao Chen Chun-lei Xuan Qiang-qiang Lu Lei Xiao Jun-qing Yang yu-bing hu Guang-Pu Zhang Ying-lei Wang Feng-qi Zhao ga-zi hao Wei Jiang National Special Superfine Powder Engineering Technology Research Center Nanjing University of Science and TechnologyNanjingChina Xi'an Modern Chemistry Research Institute Xi'anChina

Ammonium dinitramide(ADN)is considered as a potential substitute for ammonium perchlorate in energetic materials due to its high density,positive oxygen balance,and halogen-free ***,its application has been severely limited because of its strong hygroscopicity,difficult storage,and incompatibility with isocyanate curing *** order to better bloom the advantages of the highly energetic and environment-friendly ADN in the fields of energetic materials,an in-depth analysis of the current situation and discussion of key research points are particularly *** this paper,a detailed overview on the synthesis,thermal decomposition,hygroscopic mechanism,and antihygroscopicity of ADN has been discussed,its application in powdes and explosives are also presented,and its future research directions are proposed.

关键词： Ammonium dinitramide high energy oxidizer Synthesis Properties Applications

基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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