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Effects of H_2/CO/ch_4 syngas composition variation on the nO_x and CO emission characteristics in a partially-premixed gas turbine combustor

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Science ch.na(Technological Sciences) 2016年第12期59卷 1804-1813页

作者： Lee min chul Department of Safety Engineering College of EngineeringFire Disaster Prevention Research CenterIncheon National University

This paper reports the effects of variations in the fuel composition of H_2/CO/ch_4 syngas on the characteristics of nO_x and CO emissions in a partially-premixed gas turbine combustor. Combustion tests were conducted on a full range of fuel compositions by varying each component gas from 0% to 100% at heat inputs of 40 and 50 k Wth. Flame temperature, combustor liner temperature, ignition delay time, and flame structure were investigated computationally and experimentally to judge whether they are significant indicators of nO_x and CO formation. The characteristics of and reasons for nO_x and CO emissions were investigated by analyzing the emission mech.nisms and relationships among fuel property, equivalence ratio, flame temperature, liner temperature, flame shape. The flame structures were investigated using the following flame visualization methods:(1) time-averaged OH* chemiluminescence and its Abel-deconvolution;(2) direct photography; and(3) instantaneous OH-PLIF. The flame structures were greatly ch.nged by the fuel composition and heat input, and they were subjected to key affecting parameters of the temperatures of the flames and the liners. nO_x and CO emissions also largely varied according to fuel composition and heat input, showing neither linearly nor exponentially clear proportional trends toward the syngas compositions because of the singular conditions. For example, only the 100% CO flame at low load emitted lots of CO, whereas complete combustion was observed in other cases. However, the qualitative observations showed that the root causes of nO_x emission behaviors were flame temperature and flame structure, which were directly related to the residence time in the flame. Various sets of practical test results were obtained, and these results could contribute to the optimal selection of the fuel-feeding condition when fuel is ch.nged from natural gas to syngas in order to minimize nO_x and CO emissions with stable combustion.

关键词： gas turbine combustor nO_x and CO emission synthetic gas OH* chemiluminescence planar laser induced fluorescence

ALV-J感染对鸡脾脏巨噬细胞天然免疫因子的影响

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中国家禽 2024年第3期46卷 44-50页

作者：张曦谢婷婷冯敏张细权华南农业大学动物科学学院广东广州510642 农业农村部鸡遗传育种与繁殖重点试验室广东广州510642

为探究J亚群禽白血病病毒(Avian leukosis virus subgroup J,ALV-J)对鸡脾脏巨噬细胞天然免疫反应的影响,试验利用密度梯度离心法和贴壁法,从鸡脾脏组织中分离得到单核细胞,并通过显微镜观察培养至24 h、72 h、120 h单核细胞的分化过程... 详细信息

为探究J亚群禽白血病病毒(Avian leukosis virus subgroup J,ALV-J)对鸡脾脏巨噬细胞天然免疫反应的影响,试验利用密度梯度离心法和贴壁法,从鸡脾脏组织中分离得到单核细胞,并通过显微镜观察培养至24 h、72 h、120 h单核细胞的分化过程;通过PCR扩增ALV-J特异性引物H5/H7,验证脾脏巨噬细胞对ALV-J的易感情况;同时,通过qPCR验证感染ALV-J后鸡原代脾脏巨噬细胞中炎性因子、干扰素及肿瘤抑制因子的表达。结果显示:单核细胞分化至第120 h形成形态正常的巨噬细胞,通过流式细胞技术检测鸡巨噬细胞表面特异性标记蛋白发现,84.9%的细胞为KUL01阳性细胞;鸡原代脾脏巨噬细胞对ALV-J易感,并且ALV-J可整合进鸡原代脾脏巨噬细胞基因组中;对感染ALV-J的鸡脾脏巨噬细胞进行形态观察,发现ALV-J感染导致鸡脾脏巨噬细胞形态逐渐萎缩直至死亡;ALV-J感染6 h、12 h、24 h及48 h可诱导鸡原代脾脏巨噬细胞炎性因子(IL-1β、IL-6)的表达显著上调,在ALV-J感染24 h、48 h诱导肿瘤抑制因子(TnF-α)的表达显著上调(Pn-β)及干扰素刺激基因(ch25H、STAT1、PKR)表达,后期(感染48 h)抑制部分干扰素刺激基因(OAS、STAT1、ZAP、Mx、PKR)的表达。研究表明ALV-J感染鸡原代脾脏巨噬细胞早期可诱发强烈的天然免疫反应,后期可能通过抑制IFn-β及部分干扰素刺激基因的表达实现免疫逃逸。

关键词：鸡鸡原代脾脏巨噬细胞 ALV-J感染天然免疫因子

On SYMMETRIC SCALAR CURVAURE On S^2

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ch.nese Annals of Mathematics,Series B 1999年第3期20卷 325-330页

作者： JI min(Graduate School at Beijing, University of Science and Technology of ch.na, Beijing 100039, ch.na.)(Project supported by the national natural Science Foundation of ch.na (no.19631050, no.19725102)and the Foundation of the ministry of Education of ch Graduate School at Beijing University of Science and Technology of China Beijing 100039 China

Some new results are obtained for the problem of prescribing scalar curvature R on S2 when R possesses some kinds of symmetries.

关键词： Scalar curvature Symmetry Critical point minimax method

What decarbonized the residential building operation worldwide since the 2000s

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Petroleum Science 2022年第6期19卷 3194-3208页

作者： min-Da Ma min-Xia ch.n Wei Feng Jing-Wen Huo Building Technology&Urban Systems Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States School of Management Science and Real Estate Chongqing UniversityChongqing400045PR China Department of Earth System Science Tsinghua UniversityBeijing100084PR China

Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy *** accelerate the pace of global carbon neutrality,this study explores the operational carbon ch.nge in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different *** results show that(1)most of the samples showed a decrease in the total emissions from 2000 to *** for ch.na and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study *** per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon *** US almost consistently presented strong decoupling,while ch.na showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing *** 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.

关键词： Global residential building Operational decarbonization Generalized divisia index method Decoupling elasticity Building decarbonization strategies

In Vitro Propagation of Agave guiengola Gentry Using Semisolid Medium and Temporary Immersion Bioreactors

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Phyton-International Journal of Experimental Botany 2021年第3期90卷 1003-1013页

作者： Lucía Isabel chávez-Ortiz JoséFrancisco Morales-Domínguez Araceli Rodríguez-Sahagún Eugenio Pérez-Molphe-Balch Departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México Laboratorio de Biología Molecular Vegetal Centro Universitario de la CiénegaUniversidad de GuadalajaraOcotlán47820México

Agave guiengola Gentry is an endemic plant from a very small locality in Oaxaca,*** conservation status is fragile and can rapidly *** of its scarcity,this agave has been used solely for ornamental purposes,but it could have other uses if more plants were *** vitro propagation by enhanced axillary sprouting from stem segments was attained using Murashige and Skoog Basal Medium(MS)as well as basal medium supplemented with cytokinins 6-Benzylaminopurine(BA)or 6-(γ,γ-Dimethylallylamino)purine(2iP).The best treatment for shoot induction in semisolid medium consisted in MS supplemented with 2 mg l^(–1) BA,obtaining a mean of 3.7 shoots per *** interesting responses were observed,such as nodular callus induction using combinations of BA and 2,4-Dichlorophenoxyacetic acid(2,4-D);root induction without Plant Growth Regulators(PGR);and generation of shoot *** clusters constituted an excellent explant for micropropagation in temporary immersion bioreactors,obtaining a propagation rate of 43 shoots per explant with 1 min immersion and 6 h immersion *** new plants rooted and survived the transfer to *** study developed an in vitro propagation scheme to produce individuals that can be used either for reforestation,economical purposes,or to carry out studies in this species to assess its full potential,avoiding exploitation from wild plants.

关键词： Agavaceae temporary immersion systems callus induction micropropagation

碱性速凝剂对盾构壁后注浆浆体性能影响及微观机理研究

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材料导报 2024年第19期38卷 40-46页

作者：朱文超张雷张亚洲李明清张建峰闵凡路河海大学土木与交通学院南京210024 中交隧道工程局有限公司北京100102 河海大学力学与材料学院南京211100

在盾构隧道壁后注浆工程中,选择合适的速凝剂,缩短壁后注浆浆体(浆体)的凝结时间,对控制地层沉降和管片上浮至关重要。采用na_(2)CO_(3)和Li_(2)CO_(3)两种碱性速凝剂配制壁后注浆,分析了两者对浆体凝结时间、流动度经时损失和强度的影... 详细信息

在盾构隧道壁后注浆工程中,选择合适的速凝剂,缩短壁后注浆浆体(浆体)的凝结时间,对控制地层沉降和管片上浮至关重要。采用na_(2)CO_(3)和Li_(2)CO_(3)两种碱性速凝剂配制壁后注浆,分析了两者对浆体凝结时间、流动度经时损失和强度的影响规律及微观机制。结果表明:两类速凝剂均能明显缩短浆体的凝结时间,提高浆体强度,但同时导致浆体流动度经时损失加快。添加3%na_(2)CO_(3)、0.5%Li_(2)CO_(3)分别使浆体凝结时间缩短至6.5 h和8 h,2.5 h后浆体流动度保持在220 mm,浆体14 d强度为3.8 MPa,相比未添加速凝剂浆体的强度提高30%以上。微观结构分析表明,碱性速凝剂通过与石膏和ch晶体反应,促进水泥矿物C_(3)A和C_(3)S水化,缩短了浆体的凝结时间;此外,碱性速凝剂促使水泥水化产生水滑石、方解石,并激发粉煤灰生成C-A-S-H,均使浆体结构更为致密,进而提高其后期强度。

关键词：壁后注浆碱性速凝剂凝结时间流动度经时损失反应机理

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Downregulation of Hes1 expression in experimental biliary atresia and its effects on bile duct structure

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World Journal of Gastroenterology 2018年第29期24卷 3260-3272页

作者： Rui-Zhong Zhang Xin-Hao Zeng Ze-Feng Lin ming-Fu Yan-Lu Tong Vincent ch Lui Paul KH Tam Jonathan R Lamb Hui-min Xia Yan ch.n Department of Pediatric Surgery Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhou 510623Guangdong ProvinceChina Department of Surgery and Pathology University of Hong KongHong KongChina Department of Life Sciences Faculty of Natural SciencesImperial College LondonLondon SW7 2AZUnited Kingdom

AIM To analyze the expression and function of the notchsignaling target gene Hes1 in a rhesus rotavirusinduced mouse biliary atresia model. METHODS The morphologies of biliary epithelial cells in biliary atresia patients and in a mouse model were examined by immunohistochemical staining. Then, the differential expression of notch signaling pathway-related molecules was investigated. Further, the effects of the si RnAmediated inhibition of Hes1 expression were examined using a biliary epithelial cell 3 D culture *** Both immature(Ep CAM+) and mature(CK19+) biliary epithelial cells were detected in the livers of biliary atresia patients without a ductile structure and in the mouse model with a distorted bile duct structure. The hepatic expression of transcripts for most notch signaling molecules were significantly reduced on day 7 but recovered to normal levels by day 14, except for the target molecule Hes1, which still exhibited lower m RnA and protein levels. Expression of the Hes1 transcriptional co-regulator, RBP-Jκ was also reduced. A 3 D gel culture system promoted the maturation of immature biliary epithelial cells, with increased expression of CK19+ cells and the formation of a duct-like structure. The administration of Hes1 si RnA blocked this process. As a result, the cells remained in an immature state, and no duct-like structure was *** Our data indicated that Hes1 might contribute to the maturation and the cellular structure organization of biliary epithelial cells, which provides new insight into understanding the pathology of biliary atresia.

关键词： Biliary atresia Rhesus rotavirus Hes1 EpCAM Epithelial cells 3D culture

Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability

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Journal of Materials Science & Technology 2001年第2期17卷 260-262页

作者： min XU, mingxiu QUAn and Zhuangqi HU State Key Laboratory for RSA, Institute of Metal Research, ch.nese Academy of Sciences, Shenyang 110016, ch.na Lizhi ch.nG and Kaiyuan HE School of Materials and Metallurgy, northeastern University, Shenyang 110004, ch State Key Lab. for RSA Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A ferromagnetic amorphous Fe73Al4Ge2nb1P10C6B4 alloy with high glass-forming ability was synthesized by melt spinning. The supercooled liquid region before crystallization reaches about 65.7 K. The crystallized structure consists of alpha -Fe, Fe3B, FeB, Fe3P and Fe3C phases. The Fe-based amorphous alloy exhibits good magnetic properties with a high saturation magnetization and a low saturated magnetostriction. The crystallization leads to an obvious decrease in the soft magnetic properties.

关键词： Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability Am GFA

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甲烷掺氢旋流预混燃烧回火特性研究

工程热物理学报 2024年第6期45卷 1570-1578页

作者：储旭丁思宇李嘉斌杨阳赵洪亮朱民王兴建清华大学能源与动力工程系北京100084 国家管网集团北方管道公司压缩机组维检修中心廊坊065000

在节能减排与碳中和大背景下,燃气轮机燃烧室燃料逐渐向富氢方向发展。燃料掺氢后,燃烧过程更容易发生回火现象,需要对掺氢燃烧回火规律进行探究。本文选取了带钝体旋流预混燃烧室开展甲烷掺氢–空气的预混燃烧数值模拟研究,湍流模型采... 详细信息

在节能减排与碳中和大背景下,燃气轮机燃烧室燃料逐渐向富氢方向发展。燃料掺氢后,燃烧过程更容易发生回火现象,需要对掺氢燃烧回火规律进行探究。本文选取了带钝体旋流预混燃烧室开展甲烷掺氢–空气的预混燃烧数值模拟研究,湍流模型采用SST k-ω模型,湍流燃烧模型采用火焰面生成模型(FGM);准确地计算湍流火焰速度对回火现象的预测非常重要,因此对进度变量输运方程中源项的封闭考虑了掺氢对层流火焰传播速度的影响。数值模型与方法得到了实验验证,并进一步探究了当量比、入口平均轴向速度、钝体壁面热边界条件对回火现象的影响。结果表明降低当量比、提高入口平均轴向速度以及增强壁面换热对回火现象具有抑制作用。本文所总结的回火规律对于掺氢燃烧室设计具有指导意义。

关键词：掺氢燃烧 FGM 回火旋流预混燃烧