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Experimental and numerical investigations on acoustic damping of monoclinic crystalline wideband sound absorbing structures

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Journal of Central South University 2024年第6期31卷 1931-1944页

作者： xie su-chao HE Lei YAN Hong-yu ZHANG Feng-yi HE Guan-di WANG Jia-cheng Key Laboratory of Traffic Safety on Track Ministry of EducationSchool of Traffic&Transportation EngineeringCentral South UniversityChangsha 410075China Joint International Research Laboratory of Key Technology for Rail Traffic Safety Changsha 410075China National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle Changsha 410075China

In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the shape of monoclinic crystals:uniaxial oblique structure(UOS)and biaxial oblique structure(BOS).Through finite element simulation and experimental research,the theoretical models of UOS and BOS were verified,and their sound absorption mechanisms were *** the same time,the influence of multi-cavity composites on sound absorption performance was analyzed based on the theoretical model,and the influence of structural parameters on sound absorption performance was *** research results show that,in the range of 100-2000 Hz,UOS has three sound absorption peaks and BOS has five sound absorption *** frequency range of the half-absorption bandwidth(α>0.5)of UOS and BOS increases by 242% and 229%,*** with traditional microperforated sound-absorbing structures,the series and parallel hybrid methods significantly increase the sound-absorbing bandwidth of the sound-absorbing *** research has guiding significance for noise control and has broad application prospects in the fields of transportation,construction,and mechanical design.

关键词： monoclinic crystal microperforated plate acoustic metamaterials inclined cavity sound absorption

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Effecacy of Biejia(Carapax Trionycis) and Ezhu(Rhizoma Curcumae Phaeocaulis) couplet medicine on epithelial-mesenchymal transition, invasion and migration of MDA-MB-231 triple negative breast cancer cells via PI3K/Akt/mTOR signaling pathway

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Journal of Traditional Chinese Medicine 2021年第6期41卷 853-861页

作者： ZHU Manjing xie su xie Qing ZHU Jiulong HUANG Yazhen Guizhou Medical University Guiyang 550004China the Affiliated Hospital of Guizhou Medical University Guiyang 550004China

OBJECTIVE:To investigate the efficacy of Biejia(Carapax Trionycis)and Ezhu(Rhizoma Curcumae Phaeocaulis)couplet medicine on epithelial-mesenchymal transition(EMT),invasion and migration of MDA-MB-231 triple negative breast cancer(TNBC)cells based on PI3K/Akt/mTOR signaling ***:MDA-MB-231 cells were treated with different medicated serum as Biejia-,Ezhu-,Biejia-Ezhu(BJ-,EZ-,BJ-EZ-)groups,intervened with no drug rat serum and paclitaxel with final concentration of 33 nM(IC50)as negative and positive control(NC and PC)***-8 assay,scratch test,and Transwell assay were used to examine cell proliferation,invasion,and *** expression of E-cadherin,N-cadherin,Vimentin,MMP-2,MMP-9,PI3K,Akt,p-Akt,mTOR,and p-mTOR was determined by Western blot,and the m RNA expression of PI3K,Akt and mTOR was determined by real-time polymerase chain ***:BJ-EZ group inhibited proliferation after 24,48,and 72 h compared with the NC group(P<0.05,<0.01 or<0.001)and reduced the invasion and migration of MDA-MB-231 cells(P<0.01 or<0.001).In addition,BJ-EZ group upregulated the expression of E-cadherin,downregulated the expression of N-cadherin,Vimentin,MMP-2,and MMP-9(P<0.05,P<0.01 or P<0.001),and inhibited the m RNA and protein expression of PI3K,Akt(p-Akt),mTOR(p-mTOR)(P<0.05,<0.01 or<0.001).CONCLUSION:Biejia(Carapax Trionycis)and Ezhu(Rhizoma Curcumae Phaeocaulis)couplet medicine can inhibit the proliferation,invasion,migration and EMT of MDA-MB-231 cells through PI3K/Akt/mTOR signaling pathway,and the effect is better than that of Biejia(Carapax Trionycis)or Ezhu(Rhizoma Curcumae Phaeocaulis)alone.

关键词： triple negative breast neoplasms epithelial-mesenchymal transition PI3K/Akt/mTOR signal transduction Biejia(Carapax Trionycis) Ezhu(Rhizoma Curcumae Phaeocaulis)

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高效全自动数控缠绕机的设计开发

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湘潭大学学报（自然科学版） 2024年第4期46卷 85-93页

作者：付杰秦长江胡自化苏尚勇付鹏苏勰湖南江南四棱数控机械有限公司技术研发部湖南湘潭411200 湘潭大学机械工程与力学学院湖南湘潭411105

随着新能源技术的不断发展,高压气瓶的生产需求日益增长,纤维缠绕成型技术则是生产高压气瓶过程中的一种关键技术.目前纤维缠绕技术在国内发展中依然面临着许多严峻的挑战,如由于有芯纱团自身原因导致纱线缠绕张力控制不均以及缠绕手腕... 详细信息

随着新能源技术的不断发展,高压气瓶的生产需求日益增长,纤维缠绕成型技术则是生产高压气瓶过程中的一种关键技术.目前纤维缠绕技术在国内发展中依然面临着许多严峻的挑战,如由于有芯纱团自身原因导致纱线缠绕张力控制不均以及缠绕手腕运作时所需的驱动电机过多导致成本过高等问题.故该文以数控龙门式缠绕机为研究对象,设计了一种缠绕手腕装置,然后对纤维缠绕工艺进行优化,提出了一种往复式数控有芯纱团张力控制方法,并通过实验对龙门缠绕机器的性能进行验证.实验表明,经过改进后的缠绕机缠绕速度提升至150 m·min^(-1),缠绕小车运行速度提升至125 m·min^(-1).

关键词：龙门缠绕机缠绕小车纤维缠绕数控张力控制

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自闭症儿童睡眠障碍神经机制和干预研究现状

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陕西医学杂志 2024年第10期53卷 1435-1437,F0003页

作者：蒙艳谢甦赵爱平贵州医科大学临床学院贵州贵阳550025 贵州医科大学附属医院中医科贵州贵阳550001 六盘水市妇幼保健院儿童康复科贵州六盘水553000

自闭症(ASD)儿童具有较高的睡眠障碍发生率,其病发机制尚不明确。自闭症所造成的睡眠障碍可能会引起自闭症儿童社交、沟通、语言发展等多方面的障碍,增加护理难度和成本,对患儿的生长发育情况和其父母的健康生活质量都造成了较大影响。... 详细信息

自闭症(ASD)儿童具有较高的睡眠障碍发生率,其病发机制尚不明确。自闭症所造成的睡眠障碍可能会引起自闭症儿童社交、沟通、语言发展等多方面的障碍,增加护理难度和成本,对患儿的生长发育情况和其父母的健康生活质量都造成了较大影响。自闭症儿童睡眠障碍的神经机制研究能够帮助了解患儿发生睡眠障碍的生理病理原因,进一步改善患儿的治疗方案。对自闭症儿童的睡眠障碍进行多种策略干预有助于患儿的核心并发症的有效缓解。本文综述了自闭症儿童睡眠障碍的神经机制并对常见的干预策略效果进行梳理分析,旨在为临床自闭症儿童睡眠障碍的治疗提供一定文献依据和参考。

关键词：自闭症儿童睡眠障碍神经机制干预研究现状

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Synthesis and optical activity of isosorbide chiral derivative containing fluorocarbon group as chiral dopant in liquid crystal materials

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Chinese Chemical Letters 2011年第12期22卷 1447-1450页

作者： Kong Liang xie Yin He su Chun Xiang Zhang College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China

Novel isosorbide derivative containing perfluorocarbon group,bi（perfluorooctanesulfonyl）isosorbide ester as chiral dopant in liquid crystal,was *** structure was characterized by elemental analysis,FT-IR,~1H NMR and ^（19）F *** optical texture of the mixture was observed by polarized optical microscopy（POM）.Novel chiral dopant containing perfluorocarbon group had excellent optical *** specific rotation and molar rotation were noticeable higher than those of bi（4-chloromethylbenzenecarbonic）isosorbide *** fluorocarbon group improved the molar rotation of chiral compound and did not affect optical rotation *** texture of the mixture added isosorbide derivative with fluorocarbon group showed the oily streak texture.

关键词： Optical properties surfaces Texture Liquid crystal Fluorocarbon

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Multi-objective optimisation of a vehicle energy absorption structure based on surrogate model

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Journal of Central South University 2014年第6期21卷 2539-2546页

作者：谢素超周辉 Key Laboratory of Traffic Safety on Track of Ministry of Education(School of Traffic and Transportation Engineering Central South University) School of Transportation and Logistics Central South University of Forestry and Technology

In order to optimize the crashworthy characteristic of energy-absorbing structures, the surrogate models of specific energy absorption （SEA） and ratio of SEA to initial peak force （REAF） with respect to the design parameters were respectively constructed based on surrogate model optimization methods （polynomial response surface method （PRSM） and Kriging method （KM））. Firstly, the sample data were prepared through the design of experiment （DOE）. Then, the test data models were set up based on the theory of surrogate model, and the data samples were trained to obtain the response relationship between the SEA ＆amp; REAF and design parameters. At last, the structure optimal parameters were obtained by visual analysis and genetic algorithm （GA）. The results indicate that the KM, where the local interpolation method is used in Gauss correlation function, has the highest fitting accuracy and the structure optimal parameters are obtained as： the SEA of 29.8558 kJ/kg （corresponding toa=70 mm andt= 3.5 mm） and REAF of 0.2896 （corresponding toa=70 mm andt=1.9615 mm）. The basis function of the quartic PRSM with higher order than that of the quadratic PRSM, and the mutual influence of the design variables are considered, so the fitting accuracy of the quartic PRSM is higher than that of the quadratic PRSM.

关键词： railway vehicle energy-absorbing structure surrogate model Kriging method (KM) polynomial response surface method (PRSM) structure optimization

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RCA法联合戴明循环管理模式对住院患者抗菌药物治疗前病原学送检率的影响

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中华医院感染学杂志 2024年第2期34卷 272-276页

作者：谢素霞姜克文黄欣欣赵姗姗展慧莉洛阳市东方人民医院感染防控与公共卫生科河南洛阳471003 洛阳市东方人民医院神经外科河南洛阳471003

目的分析根本原因分析法(RCA)联合戴明循环管理模式对住院患者抗菌药物治疗前病原学送检率的影响。方法选取河南省洛阳市某三级综合医院2021年4—6月治疗性使用抗菌药物的病例2454例作为对照组,2021年8月1日起采取RCA法联合戴明循环管... 详细信息

目的分析根本原因分析法(RCA)联合戴明循环管理模式对住院患者抗菌药物治疗前病原学送检率的影响。方法选取河南省洛阳市某三级综合医院2021年4—6月治疗性使用抗菌药物的病例2454例作为对照组,2021年8月1日起采取RCA法联合戴明循环管理模式,2022年4—6月治疗性使用抗菌药物的病例2417例作为干预组,比较两组抗菌药物治疗前病原学送检率,包括不同级别抗菌药物、不同病原学项目及各类微生物及显微镜检查项目。结果干预组抗菌药物,限制级抗菌药物,特殊级抗菌药物治疗前病原学标本送检率分别为74.39%、74.50%、89.04%均高于对照组(P<0.001);9个临床科室中妇科除外,其余8个科室的住院患者治疗前病原学送检率均高于对照组(P<0.05);干预组各类病原学项目送检率及各类微生物培养及显微镜检查项目送检率均高于对照组(P<0.05)。结论RCA法联合戴明循环管理模式可有效提高住院患者抗菌药物治疗前病原学送检率。

关键词：病原学送检率根本原因分析法戴明循环管理模式住院抗菌药物

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Understanding surface Water-Groundwater Conversion Relationship and Associated Hydrogeochemistry Evolution in the Upper Reaches of Luan River Basin, North China

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Journal of Earth Science 2024年第3期35卷 1010-1023页

作者： Le Zhao Chunli su Wenbo Liu Xianjun xie School of Environmental Studies China University of GeosciencesWuhan 430078China State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution Ministry of Ecology and EnvironmentWuhan 430078China China Geological Environmental Monitoring Institute Beijing 100081China

Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is *** is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion *** this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July *** factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical *** indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley *** hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate *** cation exchange adsorption has minor impact on groundwater *** rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural *** main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data ***,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.

关键词： groundwater water sources conversion relationship hydrogeochemical characteristics evolutional processes water-rock interaction factor analysis Luan River Basin.

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某院住院患者抗感染药学会诊的实践情况分析

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抗感染药学 2024年第8期21卷 815-821页

作者：蔡彩敏谢根英曾国富谢素治黎碧云厦门市海沧医院药学部福建厦门361026

目的:分析医院住院患者抗感染药学会诊的实践情况,为临床药师药学会诊的开展提供参考。方法:选取2022年1月—2023年2月厦门市海沧医院收治的77例开展抗感染药学会诊的住院患者作为研究对象,采集患者的年龄、性别、所在科室、微生物检查... 详细信息

目的:分析医院住院患者抗感染药学会诊的实践情况,为临床药师药学会诊的开展提供参考。方法:选取2022年1月—2023年2月厦门市海沧医院收治的77例开展抗感染药学会诊的住院患者作为研究对象,采集患者的年龄、性别、所在科室、微生物检查结果、会诊意见及其被采纳情况、治疗结局等资料,分析接受抗感染药学会诊患者的临床特点。结果:77例接受抗感染药学会诊的患者中,男性明显多于女性(50例vs 27例),年龄上以>60岁的老年患者居多(43例,占55.84%);患者主要来自普外二科(26例,占33.77%)和泌尿疼痛科(20例,占25.97%),其次为心血管科(11例,占14.29%)和肿瘤血液科(10例,占12.99%);77例患者中微生物检查结果呈阳性的有46例,共检出病原菌46株,其中革兰阳性菌22株、革兰阴性菌22株和真菌2株;临床药师提出的会诊意见主要集中于“调整抗菌药物品种”(46例,占59.74%)和“保持当前抗感染治疗方案”(21例,占27.27%);77例患者中,有73例的药学会诊意见被医生采纳,其中患者治疗结局为康复或好转的有57例,而结局为病情加重或治疗无效的有16例。结论:医院临床药师开展药学会诊,提出个性化的药物治疗建议,受到了临床的欢迎和接受,并且很大程度上促进了患者的康复。

关键词：药学会诊抗感染治疗临床药师合理用药

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Tungsten oxide/nitrogen-doped carbon nanotubes composite catalysts for enhanced redox kinetics in lithium-sulfur batteries

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Chinese Journal of Chemical Engineering 2024年第3期67卷 58-67页

作者： Deqing He Zihao xie Qian Yang Wei Wang Chao su School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage ***,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-S ***,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal *** composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction *** a result,the WO_(3)/N-CNT-Li2S6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion.

关键词： Li-S batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics

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