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重型柴油机匹配双喷SCR系统实现超低排放的研究

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车用发动机 2024年第4期 9-16页

作者：朱敏霖王辉高建宾赵令猛李明星王晓辉广西玉柴机器股份有限公司广西玉林537000

以一款满足国六b排放标准的重型柴油机为研究对象,探索匹配双喷铜基SCR系统实现超低排放的潜力。研究表明:匹配双喷SCR系统的柴油机通过排气热管理优化、氨存储和当量喷射策略的协同优化,具有满足欧七排放草案限值的能力。同时发现,尿... 详细信息

以一款满足国六b排放标准的重型柴油机为研究对象,探索匹配双喷铜基SCR系统实现超低排放的潜力。研究表明:匹配双喷SCR系统的柴油机通过排气热管理优化、氨存储和当量喷射策略的协同优化,具有满足欧七排放草案限值的能力。同时发现,尿素喷射会大幅度增加PN排放,对PN_(10)的影响远大于对PN_(23)的影响,其中ufSCR的尿素喷射对PN_(10)排放影响较大,可通过优化SCR混合器降低PN_(10)排放。发动机本体的N_(2)O排放较低,N_(2)O主要在催化器产生,特别是SCR和ASC单元;在不同温度区间NO_(2)的生成机理和速率有较大区别,与尿素喷射量有较大关联性。

关键词：柴油机选择性催化还原喷射策略排放控制

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受古铜币灵感设计的太赫兹多波束调控反射编码超表面

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无线电工程 2024年第11期54卷 2640-2648页

作者：李银飞杨晟凡李明星秦瑶蔡成欣河南工业大学信息科学与工程学院河南郑州450001

随着研究的不断深入,太赫兹器件在多个基础研究及工程应用领域的重要地位日益凸显,但是这些器件一般只能工作在单一频点且对圆极化较敏感。为了克服这一限制,从中国古代铜币中汲取灵感,设计了一种多频点的太赫兹编码超表面,该结构由单元... 详细信息

随着研究的不断深入,太赫兹器件在多个基础研究及工程应用领域的重要地位日益凸显,但是这些器件一般只能工作在单一频点且对圆极化较敏感。为了克服这一限制,从中国古代铜币中汲取灵感,设计了一种多频点的太赫兹编码超表面,该结构由单元“0”和单元“1”构成。通过相位编码构造的1-bit太赫兹超表面可以在x线极化波和圆极化波的入射下分别在3个频点实现不同的反射波束分裂功能,进一步通过改变1-bit编码超表面的半径,可以构建2-bit太赫兹编码超表面,实现波束偏转功能。利用幅度差异可以构造幅度编码超表面在x线极化波和圆极化波的入射下实现空间成像功能。所设计的超表面解决了仅利用相位或幅度编码进行太赫兹波前操纵的问题,克服了传统器件只能在单一频点工作和对圆极化波敏感的缺陷,为太赫兹通信领域的应用提供巨大潜力。

关键词：太赫兹编码超表面多频点圆极化不敏感太赫兹成像太赫兹波束分束

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Assessment of an Evapotranspiration Deficit Drought Index in Relation to Impacts on Ecosystems

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Advances in Atmospheric Sciences 2019年第11期36卷 1273-1287页

作者： Xia ZHANG mingxing li Zhuguo MA Qing YANG Meixia LV Robin Clark Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Met Office Hadley Centre Exeter EX 1 3PB UK

Ecosystems have increasingly been subject to the challenge of heavy drought under global warming. To quantitatively evaluate the impacts of drought on ecosystems, it is necessary to develop a drought index that can sensitively depict the response of vegetation to drought evolution at a biological time scale. For the ability of direct connection between climate and ecosystem by deficit of evapotranspiration, in the present study, a drought index was defined based on standardized evapotranspiration deficit (SEDI), according to the difference between actual and potential evapotranspiration, to meet the need for highlighting drought impacts on ecological processes. Comparisons with traditional indices show that SEDI can reasonably detect droughts and climatic dry and wet transitions, especially at a monthly time scale, and can also regenerate long-term trends. Moreover, SEDI can more sensitively capture the biological changes of ecosystems in response to the dynamics of drought intensity, compared with the indices of precipitation and temperature. SEDI is more practical than the precipitation and temperature indices to highlight signals of biological effects in climate droughts. Hence, it has potential for use in assessments of climate change and its impact on ecosystems.

关键词： evapotranspiration drought index vegetation ecosystem leaf area index climate change

Soil moisture-based study of the variability of dry-wet climate and climate zones in China

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Chinese Science Bulletin 2013年第28期58卷 531-544页

作者： li mingxing MA ZhuGuo Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric Physics Chinese Academy of Sciences

An ensemble soil moisture dataset was produced from 11 of 25 global climate model (GCM) simulations for two climate scenarios spanning 1900 to 2099; this dataset was based on an evaluation of the spatial correlation of means and trends in reference to soil moisture simulations conducted using the community land model driven by observed atmospheric forcing. Using the ensemble soil moisture index, we analyzed the dry-wet climate variability and the dynamics of the climate zone boundaries in China over this 199-year period. The results showed that soil moisture increased in the typically arid regions, but with insignificant trends in the humid regions; furthermore, the soil moisture exhibited strong oscillations with significant drought trends in the transition zones between arid and humid regions. The dynamics of climate zone boundaries indicated that the expansion of semiarid regions and the contraction of semi-humid regions are typical characteristics of the dry-wet climate variability for two scenarios in China. During the 20th century, the total area of semiarid regions expanded by 11.5% north of 30°N in China, compared to the average area for 1970-1999, but that of semi-humid regions decreased by approximately 9.8% in comparison to the average for the period of 1970-1999, even though the transfer area of the humid to the semi-humid regions was taken into account. For the 21st century, the dynamics exhibit similar trends of climate boundaries, but with greater intensity.

关键词：土壤水分中国北部气候变异气候带干湿半湿润地区半干旱地区全球气候模型

Solutions of linear Differential Equations in the Unit Disc

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Journal of Mathematical Research with Applications 2014年第6期34卷 729-735页

作者： mingxing li lipeng XIAO Institute of Mathematics and Informations Jiangxi Normal University

In this paper, some properties of solutions of linear differential equations f(k)+A(z)f = 0 and f(k)+ A(z)f = F(z) are discussed. Our results are a generalization of the original results.

关键词： unit disc linear differential equations analytic function Qp space

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前牙瓷贴面美学修复体比色的影响因素

口腔医学 2024年第3期44卷 203-208页

作者：王胤霖张馨月李明星傅柏平浙江大学医学院附属口腔医院修复科浙江大学口腔医学院浙江省口腔疾病临床医学研究中心浙江省口腔生物医学研究重点实验室浙江大学癌症研究所浙江杭州310006

瓷贴面修复具有微创、美观和生物相容性良好等优势,是目前较主流的前牙美学修复技术。然而,瓷贴面修复体的比色是决定美学修复效果的重要因素。综合考量比色可以使瓷贴面与周围天然牙融为一体,从而实现自然、美观、功能相协调。该综述... 详细信息

瓷贴面修复具有微创、美观和生物相容性良好等优势,是目前较主流的前牙美学修复技术。然而,瓷贴面修复体的比色是决定美学修复效果的重要因素。综合考量比色可以使瓷贴面与周围天然牙融为一体,从而实现自然、美观、功能相协调。该综述旨在从视觉方法和数字化方法角度探讨前牙瓷贴面美学修复体比色的影响因素,为临床提供细化且具操作性的参考。

关键词：瓷贴面视觉比色数字化比色

Analysis of the Concept and Connotation of the New Economy and Reconstruction of Its Development Path:A Study Based on Chengdu’s Practices

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Contemporary Social Sciences 2022年第1期7卷 32-43页

作者： li mingxing School of Economics Sichuan UniversityChengdu

In order to promote the transformation and development of China’s economy and cope with the realistic challenges posed by the global economic recession and slowing domestic economic growth,the Fourth Session of the 12 th National People’s Congress adopted a strategic resolution on developing the "new economy" and fostering new drivers of ***,capital of Sichuan province,is one of the cities in China which firstly begin to carry out the layout of the new economy *** achieving results,it also faces many troubles due to its insufficient cognition of the connotation,definition,and path of the "new economy." The paper is based on a theoretical study in combination with the new economic development of Chengdu’s five new paths,to analyze the concept and connotation of the "new economy." It also analyzes from the perspective of higher dimensional reconstruction and new strategic path of economic development,in order to add some insights to the theorectical study and to promote better strategic value of the new economy.

关键词： new economy Chengdu perplex reconstruction strategic path

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一株高效降胆固醇乳酸菌的筛选与特性研究

中国微生态学杂志 2024年第4期36卷 401-407,413页

作者：丁小萌李明星赵芃莫湘黄元霞罗红霞杨忠华邱忠平广州中医药大学针灸康复临床医学院广东广州510405 西南交通大学生命科学与工程学院

目的筛选具有高效降胆固醇能力的干酪乳酪杆菌,以干酪乳酪杆菌标准菌株为参照研究其降胆固醇能力和益生特性,以期为心血管相关疾病防治和微生物保健品开发提供微生物资源。方法为获得安全、稳定、高效的降胆固醇益生菌,从老坛子泡菜... 详细信息

目的筛选具有高效降胆固醇能力的干酪乳酪杆菌,以干酪乳酪杆菌标准菌株为参照研究其降胆固醇能力和益生特性,以期为心血管相关疾病防治和微生物保健品开发提供微生物资源。方法为获得安全、稳定、高效的降胆固醇益生菌,从老坛子泡菜中筛选获得1株干酪乳酪杆菌S1(Lacticaseibacillus casei S1),研究了干酪乳酪杆菌S1的益生特性。结果干酪乳酪杆菌S1较标准菌株D10871的耐酸耐胆盐能力更强,人工胃肠液处理24 h后存活率可达37.06%,较D10871高237.80%(t=61.18,P<0.000 1);对几种有机溶剂的平均疏水性达60.87%,较D10871高39.41%(t=37.64,P<0.001 0);超氧自由基清除率、羟自由基清除率和还原力分别较D10871高222.86%、66.90%和2 029.03%;γ-氨基丁酸水平和脂肪酶活性分别较D10871高76.90%、83.90%;S1胆固醇去除率和胆盐水解酶活性分别较D10871高94.15%、213.20%;S1与胆盐共沉淀和菌体同化是其降胆固醇的主要方式,二者占总去除率的82.52%;抗生素敏感试验显示S1的安全性显著优于D10871。结论干酪乳酪杆菌S1是1株性能稳定、安全可靠的降胆固醇益生菌,具有重要的开发应用潜力。

关键词：干酪乳酪杆菌降胆固醇抗氧化胃肠道耐受高脂血症

低分子量肝素与阿哌沙班对髋关节置换术后下肢深静脉血栓的预防价值比较

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血管与腔内血管外科杂志 2024年第2期10卷 215-218页

作者：方钧李明星杨培伟赵枫张冬福联勤保障部队第九一〇医院骨科福建泉州362000 联勤保障部队第九一〇医院普外科福建泉州362000

目的探讨低分子量肝素与阿哌沙班对髋关节置换术后下肢深静脉血栓(DVT)的预防价值。方法收集2020年6月至2022年12月于联勤保障部队第九一〇医院住院接受髋关节置换术的217例患者的临床资料,按照使用药物的不同将其分为低分子肝素组(n=... 详细信息

目的探讨低分子量肝素与阿哌沙班对髋关节置换术后下肢深静脉血栓(DVT)的预防价值。方法收集2020年6月至2022年12月于联勤保障部队第九一〇医院住院接受髋关节置换术的217例患者的临床资料,按照使用药物的不同将其分为低分子肝素组(n=113)和阿哌沙班组(n=104)。比较两组患者的手术相关指标、术后住院期间下肢DVT发生率以及其他并发症发生率。结果两组患者手术时间、麻醉方式、术中出血量、术后住院期间治疗方法比较,差异均无统计学意义(P>0.05)。两组患者术后下肢DVT发生率、其他并发症发生率比较,差异均无统计学意义(P>0.05)。结论低分子肝素与阿哌沙班均可以安全、有效降低髋关节置换术后下肢DVT的发生率,值得临床推广应用。

关键词：髋关节置换术深静脉血栓低分子肝素阿哌沙班预防