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Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期34卷 303-322页

作者： JU Dehao liU Rui ZHENG liang DENG Jiahui ZHANG Wenzheng HUO Jinlu huang li Shanghai Marine Diesel Engine Research Institute National Key Laboratory of Marine Engine Science and Technology Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with X-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

关键词： atomization dual-orifice nozzle nozzle structure spray flame asymmetry

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Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-li Kang Yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze li Wen-li huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

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达格列净联合二甲双胍对格列美脲治疗血糖控制不佳的老年T2DM患者血糖及胰岛β细胞功能的影响

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临床合理用药 2025年第2期18卷 12-15页

作者：黄莉谢妍南昌市洪都中医院药剂科 330000 南昌市第一医院药剂科 330000

目的观察达格列净联合二甲双胍对格列美脲治疗血糖控制不佳的老年2型糖尿病(T2DM)患者血糖及胰岛β细胞功能的影响。方法选取2022年1月—2024年1月南昌市洪都中医院收治的格列美脲治疗血糖控制不佳的老年T2DM患者96例,按照随机数字表法... 详细信息

目的观察达格列净联合二甲双胍对格列美脲治疗血糖控制不佳的老年2型糖尿病(T2DM)患者血糖及胰岛β细胞功能的影响。方法选取2022年1月—2024年1月南昌市洪都中医院收治的格列美脲治疗血糖控制不佳的老年T2DM患者96例,按照随机数字表法分为研究组(n=48)和对照组(n=48)。研究组给予达格列净联合二甲双胍治疗,对照组给予二甲双胍治疗,2组均治疗3个月。比较2组治疗前后血糖、胰岛β细胞功能指标及不良反应。结果治疗3个月后,2组空腹血糖(FPG)、餐后2 h血糖(2 hPG)水平及胰岛素抵抗指数(HOMA-IR)低于治疗前,空腹胰岛素(FINS)、餐后2 h C肽(2 hCP)水平及胰岛β细胞功能指数(HOMA-β)、改良β细胞功能指数(MBCI)、胰岛素生成指数(IGI)、口服葡萄糖胰岛素敏感性指数(OGIS)高于治疗前,且研究组FPG、2 hPG水平及HOMA-IR低于对照组,FINS、2 hCP水平及HOMA-β、MBCI、IGI、OGIS高于对照组(P<0.05或P<0.01)。研究组不良反应总发生率为10.42%,与对照组的16.67%比较差异无统计学意义(χ^(2)=0.801,P=0.371)。结论格列美脲治疗血糖控制不佳的老年T2DM患者应用达格列净联合二甲双胍能降低血糖水平,改善胰岛β细胞功能,且未增加药物不良反应发生风险,安全性较高。

关键词： 2型糖尿病老年达格列净二甲双胍格列美脲血糖胰岛β细胞功能

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运动对大学生肠道菌群影响的系统综述

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中国组织工程研究 2025年第11期29卷 2394-2401页

作者：刘昭志黄丽田浩冬李岚陈晓陶云飞彭莉西南大学体育学院重庆市400715 西南大学体育学院国家体育总局体质评价与运动机能监控重点实验室重庆市400715 山东中医药大学健康学院山东省济南市250000

背景:运动对肠道菌群的调节与人体健康密切相关,但肠道菌群涉及多方面因素影响,国内外研究尚缺乏有关运动对大学生肠道菌群影响的较为一致的证据。目的:探讨运动对大学生肠道菌群多样性和物种组成的影响。方法:通过系统检索PubMed、Web ... 详细信息

背景:运动对肠道菌群的调节与人体健康密切相关,但肠道菌群涉及多方面因素影响,国内外研究尚缺乏有关运动对大学生肠道菌群影响的较为一致的证据。目的:探讨运动对大学生肠道菌群多样性和物种组成的影响。方法:通过系统检索PubMed、Web of Science、Embase、Medline、Cochrane library、中国知网、万方、维普数据库,筛选后纳入8篇实证研究,对其采用半定量的方法进行分析。结果与结论:①在运动改变大学生肠道菌群物种多样性方面,高强度间歇训练和太极拳运动均能显著提升大学生肠道菌群的物种多样性,而有氧运动对大学生肠道菌群多样性的提升效果不显著;②在运动影响肠道菌群物种组成方面,3种运动方式均能显著改变大学生肠道中菌群的组成结构,可以提高瘤胃球菌、普氏粪杆菌、布劳提亚菌等有益菌的丰度,降低埃希氏菌属等有害菌的丰度;相较于高强度间歇训练,有氧运动和太极拳运动引起了更多有益菌丰度的提升;③除肠道菌群特征的变化外,运动还可以改善大学生体成分、心肺功能以及执行功能等,这些健康效益与运动引起的菌群变化密切相关,这些菌群可通过代谢调节、屏障功能以及神经调节对机体产生健康效益;④虽然目前已有研究证实了运动与肠道菌群存在关联,但运动影响肠道菌群的机制尚未明确,同时定位与宿主健康相关的菌群是未来以肠道菌群为治疗靶点的关键,这些均值得学者进一步关注和探究。

关键词：运动干预大学生肠道菌群菌群多样性物种组成

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Misclassification analysis of discriminant model

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Applied Mathematics(A Journal of Chinese Universities) 2023年第2期38卷 180-191页

作者： huang li-wen College of Mathematics and Computer science Quanzhou Normal UniversityQuanzhou 362000China Key Laboratory of Financial Mathematics Putian UniversityPutian 351100China

This paper extends the criterion of the misclassification ratio of discriminant model and presents a new selection method of discriminant *** selecting the discriminant model,this method establishes the rule of misclassification degree ratio through misclassification ratio of the discriminant model and misclassification degree of the *** test the effect of this method,this work uses seven UCI data *** experiments on these examples indicate that this method has certain rationality and has a better effect to select a discriminant model.

关键词： discriminant model misclassi cation ratio misclassi cation degree

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Rethinking resolution estimation in fluorescence microscopy: from theoretical resolution criteria to super-resolution microscopy

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Science China(life Sciences) 2020年第12期63卷 1776-1785页

作者： Mengting li Zhen-li huang Britton Chance Center for Biomedical Photonics.Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology Wuhan 430074.China MoE Key Laboratory for Biomedical Photonics Collaborative Innovation Center for Biomedical Engineering.School of Engineering Sciences.Huazhong University of Science and TechnologyWuhan 430074China School of Biomedical Engineering Hainan UniversityHaikou 570228China

Resolution is undoubtedly the most important parameter in optical microscopy by providing an estimation on the maximum resolving power of a certain optical microscope. For centuries, the resolution of an optical microscope is generally considered to be limited only by the numerical aperture of the optical system and the wavelength of light. However, since the invention and popularity of various advanced fluorescence microscopy techniques, especially super-resolution fluorescence microscopy, many new methods have been proposed for estimating the resolution, leading to confusions for researchers who need to quantify the resolution of their fluorescence microscopes. In this paper, we firstly summarize the early concepts and criteria for predicting the resolution limit of an ideal optical system. Then, we discuss some important influence factors that deteriorate the resolution of a certain fluorescence microscope. Finally, we provide methods and examples on how to measure the resolution of a fluorescence microscope from captured fluorescence images. This paper aims to answer as best as possible the theoretical and practical issues regarding the resolution estimation in fluorescence microscopy.

关键词： fluorescence microscopy super-resolution microscopy Abbe limit Rayleigh criterion image resolution

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Pre-chamber turbulent jet ignition of methane/air mixtures with multiple orifices in a large bore constant volume chamber: effect of air-fuel equivalence ratio and pre-mixed pressure

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Frontiers in Energy 2019年第3期13卷 483-493页

作者： Xiang li Wenzheng ZHANG Zhong huang Dehao JU li huang Mingzhi FENG Xingcai LU Zhen huang Key Laboratory of Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China Shanghai Marine Diesel Engine Research Institute Shanghai 201108China

liquefied natural gas (LNG), mainly composed of methane, is in progress to substitute diesel fuel in heavyduty marine engine for practical, economic, and environmental considerations. However, natural gas is relatively difficult to be ignited in a large bore combustion chamber. A combustion enhancement technique called prechamber turbulent jet ignition (TJI) can permit combustion and flame propagation in a largebore volume. To investigate the effect of air-fuel equivalence ratio and pre-mixed pressure on pre-chamber TJI of methane/air mixtures with multiple orifices in a large bore volume, experimental tests and computational simulations were implemented to study the discharge of hot turbulent jets from six orifices of the pre-chamber. Different initial pressures and air-fuel equivalence ratios were considered to analyze the characteristics of TJI. The asymmetry of the turbulent jet actuated from six different orifices were found due to the asymmetric orientation of the spark plug, resulting in the inhomogeneous distribution of combustion in the constant volume chamber, which should be considered seriously in the marine engine design. Besides,as the premixed pressure increases, it has more effect on the flame propagation and plays a more important role, as it further increases.

关键词： marine engine natural gas methane turbulent jet ignition (TJI) pre-chamber

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A euryarchaeal histone modulates strand displacement synthesis by replicative DNA polymerases

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Science China(life Sciences) 2016年第7期59卷 709-716页

作者： Fei Sun li huang State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences

Euryarchaeota and Crenarchaeota, the two main lineages of the domain Archaea, encode different chromatin proteins and differ in the use of replicative DNA polymerases. Crenarchaea possess a single family B DNA polymerase(Pol B), which is capable of strand displacement modulated by the chromatin proteins Cren7 and Sul7 d. Euryarchaea have two distinct replicative DNA polymerases, PolB and PolD, a family D DNA polymerase. Here we characterized the strand displacement activities of Pol B and Pol D from the hyperthermophilic euryarchaeon Pyrococcus furiosus and investigated the influence of HPf A1, a homolog of eukaryotic histones from P. furiosus, on these activities. We showed that both Pol B and Pol D were efficient in strand displacement. HPf A1 inhibited DNA strand displacement by both DNA polymerases but exhibited little effect on the displacement of a RNA strand annealed to single-stranded template DNA. This is consistent with the finding that HPf A1 bound more tightly to double-stranded DNA than to a RNA:DNA hybrid. Our results suggest that, although crenarchaea and euryarchaea differ in chromosomal packaging, they share similar mechanisms in modulating strand displacement by DNA polymerases during lagging strand DNA synthesis.

关键词： euryarchaea PolB PolD strand displacement archaeal histone

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Preparation and properties of physically and chemically cross-linked hybrid hydrophobic association hydrogels with good mechanical strength

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Science China Chemistry 2016年第3期59卷 282-292页

作者： Guoqing Jiang li huang Bo li Quan Zhou Zhiying li Enhanced Oil Recovery Laboratory Exploration and Development Research InstituteDaqing Oilfield Company LimitedDaqing163712China State Key Laboratory of Enhanced Oil Recovery Petrochina Research Institute of Petroleum Exploration&DevelopmentBeijing100083China Production Engineering&Research Institute Daqing Oilfield Company LimitedDaqing163453China College of Chemistry Jilin UniversityChangchun130012China

To correct the defects of hydrophobic association hydrogels （HA-gels）, new physically and chemically cross-linked hybrid hy- drophobic association hydrogels （hybrid HA-gels） were prepared by radical copolymerization of acrylamide （AM）, octylphe- nol polyoxyethylene （n） acrylate （OPnAC, n stands for the number of ethoxy group, and is 10 and 21） and N,N＇-methylene- bisacrylamide （MBA）. On the basis of the statistical molecular theory of rubber elastic, the Mooney-Rivlin model and using the tensile true stress （O＇true） tested at room temperature, the number of network strands per unit volume （o~） and the num- ber-average molar mass of a network strand （Me） were evaluated for hybrid HA-gels. For the hydrogels, the effect of the con- tent of MBA and OP10AC on their tensile mechanical properties was studied by using o0 and Mc; also, the effect of the com- positions and temperature on their swelling behavior in distilled water was discussed in detail. In addition, hybrid HA-gels in- cluding a small quantity of MBA possessed the capabilities of secondary self-healing and remolding. In contrast with HA-gels prepared by the same compositions besides MBA, hybrid HA-gels showed good mechanical strength and long-term thermal stability in distilled water in the range of 25 to 80℃. Furthemore, hybrid HA-gels also avoided the self-deswelling behavior of HA-gels. The results show that the application fields of HA-gels will be greatly broadened after introducing a chemical cross-linking network.

关键词： hydrophobic association hydrogels hybrid hydrogels mechanical properties swelling behavior reforming capability

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A linear Operator Method to Compute the Normal Modes with Rotation of any Asymmetric 3D Planet with Pure Vector Spherical Harmonics

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Research in Astronomy and Astrophysics 2023年第10期23卷 224-254页

作者： Mian Zhang Cheng-li huang CAS Key Laboratory of Planetary Sciences Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surface spherical harmonics(GSSHs) are usually applied to the elliptical models with a stress tensor, which cannot be expressed in vector spherical harmonics explicitly. However, GSSHs involve complicated math. LOM is an alternative to GSSHs,whereas it only deals with the coupling fields of the same azimuthal order m, as is the case when a planet model is axially symmetric and rotates about that symmetry axis. We extend LOM to any asymmetric 3D model. The lower degree spheroidal modes of the Earth are computed to validate our method, and the results agree very well with what is observed. We also compute the normal modes of a two-layer Saturn model as a simple application.

关键词： planets and satellites:interiors Earth planets and satellites:gaseous planets

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