检索结果-南通市图书馆

Numerical Investigation of Three-dimensional Aeroacoustic Characteristics of Owl-inspired Trailing-edge Fringes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2023年第3期20卷 1103-1120页

作者： Jiaxin rong Hao Liu Shanghai Jiao Tong University and Chiba University International Cooperative Research Center(SJTU-CU ICRC) Shanghai200240China Graduate School of Engineering Chiba University1-33Yayoi-choInage-kuChiba263-8522Japan

Owls are widely known for their silent flight,which is attributed to their unique wing morphologies comprising leading-edge(LE)serrations,trailing-edge(TE)fringes,and a velvety *** aeroacoustic characteristics of owl-inspired TE fringes have been widely investigated through two-dimensional(2D)modeling,but remain yet poorly studied in association with their three-dimensional(3D)***,we present a numerical study of the 3D aeroacoustic characteristics of owl-inspired TE fringes in which we combined large-eddy simulations(LES)with the Ffowcs Williams‒Hawkings *** constructed a clean wing model and three wing models with TE fringes that were distributed differently *** aerodynamic forces and 3D acoustic characteristics reveal that,like the 2D results of our previous studies,the 3D TE fringes enable remarkable sound reduction spatially while having aerodynamic performance comparable to the clean *** of the near-field 3D flow structures,vortex dynamics,and flow fluctuations show that TE fringes can robustly alter the 3D flow by breaking 3D TE vortices into small eddies and mitigating 3D flow ***,it is verified that TE fringes alter spanwise flows,thus dominating the 3D aeroacoustic characteristics in terms of passive flow control and flow stabilizations,whereas the fringes are inefficient in suppressing the acoustic sources induced by wingtip ***,the TE fringes distributed at midspan have better acoustic performance than those in the vicinity of the wingtip,indicating the importance of a spanwise distribution in enhancing aeroacoustic performance.

关键词： Owl Three-dimensional trailing-edge fringes Aeroacoustics Large-eddy simulation Ffowcs Williams‒Hawkings equation

益生菌联合胰岛素泵治疗妊娠期糖尿病患者的效果观察

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国妇幼保健 2024年第16期39卷 3007-3011页

作者：吴丽霞罗荣康王文斌丽水市人民医院内分泌科丽水市人民医院急诊医学科杭州市第一人民医院内分泌科

目的探讨益生菌联合胰岛素泵治疗妊娠期糖尿病（GDM）患者的效果。方法选取2021年3月—2022年3月丽水市人民医院收治的104例GDM患者，随机分为对照组和观察组，每组各52例。对照组给予胰岛素泵治疗，观察组在对照组基础上给予益生菌... 详细信息

目的探讨益生菌联合胰岛素泵治疗妊娠期糖尿病（GDM）患者的效果。方法选取2021年3月—2022年3月丽水市人民医院收治的104例GDM患者，随机分为对照组和观察组，每组各52例。对照组给予胰岛素泵治疗，观察组在对照组基础上给予益生菌治疗。比较两组血糖[空腹血糖（FBG）、餐后2 h血糖（2 h PG）、糖化血红蛋白（HbA1c）]及血脂[三酰甘油（TG）、总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（LDL-C）]水平、胰岛素抵抗和胰岛素水平[空腹胰岛素（FINS）、胰岛素抵抗指数（HOMA-IR）]、血清氧化相关物质[还原型谷胱甘肽（GSH）、超氧化物歧化酶（SOD）、活性氧类物质（ROS）活性]及母婴结局。结果治疗后，观察组FBG、2 h PG、HbA1c水平分别为（5.16±0.69）mmol/L、（6.29±1.33）mmol/L、（6.65±1.10）%,均明显低于对照组的（5.90±0.96）mmol/L、（7.30±1.62）mmol/L、（7.55±1.23）%,差异均有统计学意义（均P<0.05）。治疗后，观察组TG、TC、LDL-C水平分别为（1.58±0.35）mmol/L、（5.39±0.45）mmol/L、（3.22±0.25）mmol/L,均明显低于对照组的（1.94±0.52）mmol/L、（5.82±0.47）mmol/L、（3.72±0.31）mmol/L,差异均有统计学意义（均P<0.05）,HDL-C水平为（1.21±0.27）mmol/L,明显高于对照组的（1.05±0.22）mmol/L,差异有统计学意义（P<0.05）。治疗后，观察组FINS、HOMA-IR水平分别为（16.10±3.42）mU/L、（3.69±1.02）,均明显低于对照组的（19.63±3.65）mU/L、（5.14±1.36）,差异均有统计学意义（均P<0.05）。治疗后，观察组GSH、SOD水平分别为（29.00±5.13）μmol/L、（20.64±3.78）U/L,均明显高于对照组的（25.42±4.36）μmol/L、（18.10±3.52）U/L,ROS水平为（617.58±31.28）U/ml,明显低于对照组的（642.21±50.05）U/ml,差异均有统计学意义（均P<0.05）。观察组母婴不良结局总发生率为7.69%,明显低于对照组的25.00%（χ2=4.300,P<0.05）。结论益生菌联合胰岛素泵治疗可有效控制GDM患者的血糖和血脂水平，改善胰岛素抵抗和胰岛素水平，调节血清氧化相关物质，降低母婴不良结局发生率。

关键词：益生菌胰岛素泵妊娠期糖尿病疗效

Fabrication of sintering-free flexible copper nanowire/ polymer composite transparent electrodes with enhanced chemical and mechanical stability

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2016年第7期9卷 2162-2173页

作者： cho rong Chu Changsoo Lee Jahyun Koo Hyuck Mo Lee Department of Materials Science and Engineering KAIST 291 Daehak-ro Yuseong-gu Daejeon 305-701 Republic of Korea

The thermal decomposition synthesis of long copper nanowires （CuNWs） was achieved by controlling the synthesis parameters. A detailed study was performed to determine the effect of the molar ratio of copper chloride to nickel acetylacetonate, temperature, and stirring rate on the final shape of the products. Transparent electrodes （TEs） were fabricated by wet treatment with acetic acid （AA）, without using a sintering process. The low oxidation stability and high surface roughness are the main disadvantages of the CuNW TEs, which limit their applications. In order to overcome these issues, we prepared CuNW/polymer composite TEs by partial embedding of the CuNWs into poly（methyl methacrylate）（PMMA） on poly（ethylene terephthalate）（PET） substrates. The CuNW/PMMA composite TEs exhibit excellent optoelectronic performance （91.3% at 100.7 ff2/sq）, low surface roughness （4.6 nm in height）, and good mechanical and chemical stability as compared with CuNW TEs. On the basis of these properties, we believe that CuNW-based composite TEs could serve as low-cost materials for a wide range of new optoelectronic devices.

关键词： copper nanowires nanowire/polymercomposite transparent electrode chemical stability mechanical stability

肝炎肝硬化患者肝功能生化检验的临床应用价值观察

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国现代药物应用 2024年第5期18卷 61-64页

作者：罗小攀熊春容武汉市东湖新技术开发区豹澥街社区卫生服务中心 430200 鄂州市鄂州二医院检验科 436000

目的探讨肝功能生化检验在肝炎肝硬化患者中的临床应用价值,以便为临床治疗提供参考。方法选择72例肝炎肝硬化患者作为观察组, 50例健康体检者作为对照组。两组均开展肝功能生化检验。比较两组的肝功能生化指标[总胆汁酸(TBA)、白蛋白... 详细信息

目的探讨肝功能生化检验在肝炎肝硬化患者中的临床应用价值,以便为临床治疗提供参考。方法选择72例肝炎肝硬化患者作为观察组, 50例健康体检者作为对照组。两组均开展肝功能生化检验。比较两组的肝功能生化指标[总胆汁酸(TBA)、白蛋白(ALB)、总胆固醇(TC)、胆碱酯酶(CHE)及胆固醇(cho)],观察组不同Child-Pugh分级肝功能生化指标。结果对照组TBA、ALB、CHE、cho及TC水平分别为(6.25±0.72)μmol/L、(47.45±5.64)g/L、(5854.67±354.25)U/L、(4.11±0.74)mmol/L、(5.17±1.42)mmol/L,观察组分别为(39.78±5.16)μmol/L、(30.32±4.26)g/L、(2378.71±268.67)U/L、(2.93±0.51)mmol/L、(3.89±0.83)mmol/L,与对照组比较,观察组TBA水平升高, ALB、TC、CHE及cho水平均降低,差异有统计学意义(Pcho水平比较差异具有统计学意义(Pcho水平高于Child B级、Child C级, Child B级患者TBA水平低于Child C级, ALB、TC、CHE及cho水平高于Child C级,差异具有统计学意义(P<0.05)。结论肝炎肝硬化临床检测过程中使用肝功能生化检验,能有效对患者的肝功能状态进行评估,可判断其肝组织损伤程度,具有临床推广意义。

关键词：肝炎肝硬化肝功能 Child-Pugh分级生化指标

不同通风策略下大规模鸭粪堆肥的腐熟和光谱特征

在线全文

学校读者我要写书评

暂无评论

植物营养与肥料学报 2024年第3期30卷 575-586页

作者： Zubair Muhammad 柳夏艳李兆君王建才朱荣生山东省农业科学院畜牧兽医研究所山东济南250100 北京林业大学/水体污染源控制技术重点实验室北京100083 中国农业科学院农业资源与农业区划研究所北京100081

[目的]鉴于鸭粪处理的固有挑战,有效的通风措施是鸭粪工业堆肥过程成功的关键。这项开创性的研究旨在评估来自鸭粪和蘑菇废弃物堆肥的腐熟度和稳定性。本研究进一步探讨了各种通风策略在促进堆肥过程中有机物分解和转化方面的有效性和... 详细信息

[目的]鉴于鸭粪处理的固有挑战,有效的通风措施是鸭粪工业堆肥过程成功的关键。这项开创性的研究旨在评估来自鸭粪和蘑菇废弃物堆肥的腐熟度和稳定性。本研究进一步探讨了各种通风策略在促进堆肥过程中有机物分解和转化方面的有效性和效率。[方法]将鸭肥和蘑菇废弃物按干重比为2∶1(C/N约为21.15)混合进行堆肥试验。堆肥采用梯形桩,每桩体积5.6 m^(3),采用管道通风。堆肥试验包括4个通气时间处理,分别为10、20、30、60 min/d(分别记作C1、C2、C3和C4处理)。主要研究了堆肥过程中物理化学特性、紫外-可见光谱、X射线衍射(XRD)和红外光谱(IR)的变化特征。[结果]在堆肥第5天和第6天,堆肥进入嗜热期,持续17天,第15天达到50℃。在堆肥前5天,堆肥pH从8.5迅速上升到12.3,可能是由于鸭粪蛋白质的分解,然后在接下来的20天里逐渐下降,在28~30天急剧下降,之后逐渐下降。在高温期(第17天)后,堆肥C1、C2、C3和C4处理的含水量较堆肥初期分别减少了45.9%、46%、44.7%和43%。C3和C4处理的TC值远低于C1和C2。所有堆肥处理的紫外吸收均随波长的增加而降低。在X射线衍射图中存在部分纤维素特征峰(2θ=26.56°)。这些样品含有更多的结晶和“无定形”纤维素、木聚糖和其他多糖。在200~220 nm光谱范围内,硝酸盐和羧基类化学物质的吸收速度比芳香族或不饱和分子快。堆肥的吸收率随初始碳氮比和堆肥过程的持续时间而变化。相反,在460~480 nm处的吸光度表明有机材料的腐殖质化。Q2/6或Q4/6值越低,表明有机物腐殖化程度越高和越多的有机物缩合成芳香族化合物。在红外光谱中,整个堆肥过程中与有机或无机官能团相关的所有条带的强度都有明显的变化。红外光谱显示出一个宽峰,中心波数为3400 cm^(-1),表明存在与羟基(oh)基团和水分子相关的拉伸振动。在3000~2800 cm^(-1)的光谱范围内,可以观察到一个与有机化合物所表现出的疏水特性相关的现象。在2900~2850 cm^(-1)处存在的条带可以归因于C-H脂肪族基团和醛基基团(cho)的伸缩振动。初始堆肥样品和C1、C2、C3、C4的红外光谱在堆肥过程中发生了显著变化。由于这些变化,红外光谱吸收带发生了显著的变化,表明相关的物质结构发生了变化。因此,C3和C4在堆肥过程中表现出较高程度的稳定性。[结论]65天的堆肥试验显示,在整个堆肥过程中,温度发生变化,通风60 min/d的堆肥最高温度高于通风10 min/d的堆肥。在堆肥过程中,随着通气量的增加,pH呈下降趋势,因此,日通风30~60 min的堆肥pH较低。堆肥过程中,堆料C/N逐渐降低,表明纤维素活性增加。XRD光谱显示峰值强度降低,反映了纤维素的分解。日通风30~60 min堆肥表现出较高的成熟度,突出了通风对成功堆肥的重要性。

关键词：鸭粪蘑菇废弃物堆肥通风成熟度

川西北高寒地区5种饲草产量与CNCPS组分分析

在线全文

学校读者我要写书评

暂无评论

草地学报 2024年第6期32卷 1672-1681页

作者：张雯露黄雄杰李容汪辉关皓周青平陈有军西南民族大学草地资源学院四川成都610041 西南民族大学四川若尔盖高寒湿地生态系统国家野外科学观测研究站四川成都610041

饲草种质资源是新品种创制的基础,本研究选择适宜在川西北高寒区栽培的中华羊茅(Festuca sinensis)、无芒雀麦(Bromus inermis)、垂穗披碱草(Elymus nutans)、圆柱披碱草(Elymus cylindricus)和老芒麦(Elymus sibiricus)饲草种质资源,... 详细信息

饲草种质资源是新品种创制的基础,本研究选择适宜在川西北高寒区栽培的中华羊茅(Festuca sinensis)、无芒雀麦(Bromus inermis)、垂穗披碱草(Elymus nutans)、圆柱披碱草(Elymus cylindricus)和老芒麦(Elymus sibiricus)饲草种质资源,测定了饲草产量、全株及不同部位(茎、叶、穗)的营养成分,利用康奈尔净碳水化合物-蛋白质体系(Cornell net carbohydrate and protein system, CNCPS)对其组分进行分析,为筛选高产优质饲草种质资源奠定基础。结果表明,鲜草产量随年份增加逐年降低,老芒麦连续四年的鲜草产量高于其他饲草。圆柱披碱草的干草产量最高,变异系数较小,稳产性较好。无芒雀麦茎、叶和穗的中性洗涤纤维(Neutral detergent fiber, NDF)、酸性洗涤纤维(Acid detergent fiber, ADF)含量低于其他饲草,非结构性碳水化合物(Nonstructural carbohydrate, NSC)含量显著高于其他饲草(Pohydrate, cho)含量低于其他饲草。综合分析得出,无芒雀麦和老芒麦的生产性能及营养品质表现较好,可作为当地种质资源研究和新品种选育的基础材料。

关键词：川西北饲草产量康奈尔净碳水化合物-蛋白质体系粗蛋白碳水化合物

维普期刊数据库博看期刊

同方期刊数据库

FT-ICR mass spectrometry for molecular characterization of water-insoluble organic compounds in winter atmospheric fine particulate matters

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2022年第1期34卷 51-60页

作者： Cuiping Ning Yuan Gao Haoran Yu Haijun Zhang Ningbo Geng rong Cao Jiping Chen CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China University of Chinese Academy of Sciences Beijing 100049China

Water-insoluble organic compounds(WIOCs)are an important fraction of atmospheric fine particulate matters(PM_(2.5)),which could affect the climate system and threaten human health *** this study,molecular characterization of WIOCs in PM_(2.5) were investigated by 15 T Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)with atmospheric pressure photoionization(APPI)source in positive ion mode.A total of 2573 and1875 molecular formulas were identified in WIOCs extracted by dichloromethane,which were collected in hazy and normal days,*** identified molecular formulas were further classified into four major subgroups,including CH,CHN,cho and CHNO *** compounds predominated in WIOCs,accounting for more than 60%in both *** compounds(26.6%)and CH compounds(16.1%)were the second highest subgroups in WIOCs from the hazy days and normal days,*** relative abundance and number of nitro-substituted aromatic compounds were significantly higher in hazy days than in normal *** molecular composition of WIOCs was more complex in hazy days while more aromatic compounds were identified in normal days.

关键词： PM_(2.5) WIOCs FT-ICR MS Molecular characteristics Polycyclic aromatic hydrocarbon

Oxidation-enhanced bonding strength of Cu sinter joints during thermal storage test

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第20期115卷 251-255页

作者： Yue Gao Jinting Jiu Chuantong Chen Katsuaki Suganuma rong Sun Zhi-Quan Liu Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Senju Metal Industry Co. Ltd.Senju Hashido-cho 23Adachi-ku Tokyo 120-8555Japan The Institute of Scientific and Industrial Research(ISIR) Osaka UniversityMihogaoka 8-1IbarakiOsaka 567-0047Japan Shenzhen College of Advanced Technology University of Chinese Academy of SciencesShenzhen 518055China

With the development in next-generation semiconductor power devices,the power devices based on silicon carbide(SiC)and gallium nitride(GaN)are expected to replace the traditional Si-based power devices[1–6].However,the foreseeable harsh operating environment such as heavy thermal-load or extremely temperature cycle required more reliable interconnection technology[4,7-9].

关键词： interconnection thermal bonding

ESTABLISHMENT OF ASSESSMENT SYSTEM FOR STRUCTURAL FLOOD CONTROL MEASURES

在线全文

学校读者我要写书评

暂无评论

Tropical Cyclone Research and Review 2019年第1期8卷 46-52页

作者： cho-rong KIM Department of Land Water and Environment Research Korea Institute of Civil Engineering and Building Technology

Due to abnormal weather environment such as global warming and greenhouse effect, the risk of flood has been increased with larger scale of flood damages. In this regard, it is needed to establish a comprehensive and integrated system to evaluate the most optimized measures for flood control through eliminating uncertainties of socio-economic impacts. Assessment System of Structural Flood Control Measures(ASFCM) was developed for determining investment priorities of the flood control measures and establishing the social infrastructure projects. ASFCM consists of three modules: 1) the initial setup and inputs module, 2) the flood and damage estimation module, and 3) the socio-economic analysis ***, the D/B for flood damage estimation was constructed, which is the initial and input data about the estimation unit, property, historical flood damages, and topographic and hydrological data in the target area were applied. After that, it is important to classify local characteristic for constructing flood damage data. Five local characteristics(big city, medium size city, small city, farming area, and mountain area) are classified by criterion of application(population density). Next step is the floodplain simulation with HEC-RAS which is selected to simulate inundation. Through inputting the D/B and damage estimation, it is able to estimate the total damage(only direct damage) that is the amount of cost to recover the socio-economic activities back to the safe level before flood did occur. The last module suggests the economic analysis index(B/C ratio) with Multidimensional Flood Damage. Consequently, ASFCM suggests the reference index in constructing flood control measures to reduce water-related damage and decision-makers can choose the proper flood control measures in the socioeconomic aspects.

关键词： ASFCM socio-economic assessment flood damage structural flood control HEC-RAS