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Evaluation of oxygen uncoupling characteristics of oxygen carrier using micro-fluidized bed thermogravimetric analysis

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Chinese Journal of Chemical Engineering 2021年第4期34卷 408-415页

作者： Lei liu Zhenshan li ye li Ningsheng Cai Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Oxygen uncoupling characteristics of a natural manganese ore and a perovskitetype oxide CaMn_(0.5)Ti0_(37)5Fe_(0.125)O_(3)were studied by using a microfluidized bed thermogravimetric analysis(MFBTGA)technology which is based on a realtime mass measurement of fluidizing particles inside a bubbling bed *** chemical stability,kinetics of the oxygen release and uptake reactions and fluidization property were investigated and the experimental data measured by MFBTGA were compared with the results in a regular TGA instrument(TGA Q500).The regular TGA Q500 results show the reactivity of both the manganese ore and perovskite oxide are stable for multi cycles,and the oxygen uncoupling capacity of the manganese ore is~1.2%(mass)which is~2 times higher than that of the perovskite ***,the experimental results from the MFBTGA indicated that there is a serious agglomeration for the manganese ore.A very important finding is that the reaction rate of oxygen release and oxygen uptake of the perovskite oxide measured by the MFBTGA are~2 and~4 times faster than that of testedby the TGA *** can conclude that MFBTGA is a very useful tool to measure the reactivity stability and kinetics of oxygen carriers in highthroughput analysis instead of the regular TGA.

关键词： CO_(2)capture Oxygen carrier Oxygen uncoupling Fluidized-bed Thermogravimetric analysis Agglomeration

Measured Impedance and Threshold Value of Electrode line Impedance Supervision Based Protection in HVDC Transmission System

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1294-1304页

作者： Qiang Sun Bin li Jiawei He ye li Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjinChina State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina

At present,electrode line impedance supervision(EliS)based protection is widely used to detect faults on grounding electrode lines,which are indispensable elements of high-voltage direct current(HVDC)*** existing theoretical analysis of measured impedance is based on lumped line model and the threshold value is generally set according to engineering experience,which have caused the dead zone problem and even ***,a study on measured impedance of EliS-based protection and its threshold value selection method is carried out to solve this *** this study,the expressions of measured impedance under normal operation and fault conditions are deduced based on rigorous and accurate line *** on the expressions,the characteristics of the measured impedance are calculated and *** the characteristics of the measured impedance,the applicability of the protection with the traditional threshold value is further discussed and the distribution of the dead zone can be ***,the method to calculate the threshold value of EliS-based protection is *** a proper threshold value selected by the proposed method,the dead zone of EliS-based protection is effectively eliminated,and the protection can identify all types of faults even with large transition *** studies on PSCAD/EMTDC have been conducted to verify the conclusion.

关键词： Grounding electrode line electrode line impedance supervision(EliS)based protection measured impedance characteristic threshold value selection

Arsenic biotransformation in industrial wastewater treatment residue: Effect of co-existing Shewanella ***-3 and MR-1

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Journal of Environmental Sciences 2022年第8期34卷 14-20页

作者： Hao li lixin Zhang li ye Chuanyong Jing State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Science and Engineering Shandong UniversityQingdao 266237China

Shewanella sp. ANA-3 with the respiratory arsenate reductase(ArrAB) and MR-1 with ferric reduction ability always coexist in the presence of high arsenic(As)-containing waste residue. However, their synergistic impacts on As transformation and mobility remain unclear. To identify which bacterium, ANA-3 or MR-1, dominates As mobility in the coexisting environment, we explored the As biotransformation in the industrial waste residue in the presence of Shewanella sp. ANA-3 and MR-1. The incubation results show that As(Ⅲ)was the main soluble species, and strain ANA-3 dominated As mobilization. The impact of ANA-3 was weakened by MR-1, probably due to the survival competition between these two bacteria. The results of micro X-ray fluorescence and X-ray photoelectron spectroscopy analyses further reveal the pathway for ANA-3 to enhance As mobility. Strain ANA-3 almost reduced 100% surface-bound Fe(Ⅲ), and consequently led to As(V) release. The dissolved As(V) was then reduced to As(Ⅲ) by ANA-3. The results of this study help to understand the fate of arsenic in the subsurface and highlight the importance of the safe disposal of high As-containing industrial waste.

关键词： Arsenic Shewanella sp.ANA-3 and MR-1 Coexistence Biotransformation Waste residue

Solvent effects on photophysical properties of copper and zinc porphyrins

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Chinese Science Bulletin 2008年第23期53卷 3615-3619页

作者： li ye Department of Chemistry School of Applied Science Beijing University of Science and Technology Beijing 100083 China

The photophysics of Zn(tetraphenylporphyrin,TPP), Zn(tetra-2,4,6-trimethylphenyl porphyrin, TMP), Zn (tetra-(o-dichlorophenyl) porphyrin, TPPCl8), Cu(tetraphenylporphyrin,TPP), Cu(tetra-2,4,6-trimethyl- phenyl porphyrin,TMP), and Cu(tetra-(o-dichlorophenyl) porphyrin, TPPCl8, TPPCl8) in several solvents have been investigated on steady state and time-resolved spectroscopy. The Cu(TPPCl8 ) is normal and shows no evidence of CT transition in the visible or near UV regions in nonpolar solvent. However, Cu(TPPCl8)shows a blue shift in the absorption spectrum and intramolecular CT bands at absorption spectra in polar solvent, which shows a fluorescence maximum emission at 650 nm and 8.4 ns lifetime. The reason can be attributed to two points. Firstly, the increase of solvent polarity can enlarge outer reorganisational energy, which is favorable to reduce the activation free energy of charger-transfer transition based on Marcus theory of electron transfer. Moreover, the internal heavy-atom effect on Cu(TPPCl8) is encouraging to stabilize the 2T1 state also, which increases the possibility of population to CT band from 2T1 state. This result is in accord with an earlier estimate of a 10 ns lifetime and CT absorption at 640 nm bands for the CT state of Cu (II) octethylporphyrins. Other possible reasons arousing unusual fluorescence like H-bonding, axial ligands, molecular aggregation are excluded.

关键词：金属卟啉荧光性电荷转移极性

Polyhedrosis Virus in Bacillus thuringiensis

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Agricultural Sciences in China 2011年第1期10卷 92-100页

作者： ye Xiang-li XIA li-qiu Key Laboratory of Microbial Biology of Hunan Province/College of life Science Hunan Normal University Changsha 410081 P.R China College of Medicine Hunan Normal University Changsha 410013 P.R.China

This study was conducted to build a recombinant strain with highly insecticidal activity and a wide host range by using the crylAc and p74 gene. Firstly, the p74 gene was amplified from the genosome ofAutographa californica multicapsid nucleopolyhedrovirus. The crylAc gene and the terminator gene of crylAc, named crylAct, were amplified from the plasmid of Bt 4.0718 strain. Three T vectors, named pTp74, pT1Ac, and pT1Act which held the aimed gene p74, cry1Ac, and crylAct, respectively, and two middle vectors, named pTp74Act and pTIAcp74 which held the aimed fusion gene p74-crylAct and cry lAc-p74, respectively, were built by using pMDI 8-T. Then pTiAcp74 and the shuttle plasmid were digested and linked and an expressing-vector pH1Acp74 was built. Finally, pH1Acp74 was transformed into the acrystalliferous strain XBU001 and the aimed recombinant strain XBU-H1Acp74 was obtained. The expression of Bt transformant XBU-H1Acp74 was analyzed by SDS-PAGE which showed XBU-H1Acp74 could produce 130 kDa CrylAc protein and 50 kDa P74 protein. The insecticidal activity of transformant against Spodoptera exigua was evaluated compared with the contrast strains HTX-42 （only crylAc gene was transformed into XBU001） after autolysis. The LCs0 of HTX-42 was higher than that of the XBU-H IAcp74＇s, which implied that P74 could increase the efficacy and range of Bt Cry toxins in insect control. The fusion gene of crylAc and p74 were constructed successfully which will be served as the foundation lbr constructing the fusion genes of Bt cry gene and other foreign genes.

关键词： Bacillus thuringiensis Autographa californica multicapsid nucleopolyhedrovirus crylAc gene p74 gene fusion gene

Bionic Leaf Simulating the Thermal Effect of Natural Leaf Transpiration

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Journal of Bionic Engineering 2014年第1期11卷 90-97页

作者： Zhi Yuan Hong ye Shimin li Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 P. R. China

We proposed a kind of bionic leaf to simulate the thermal effect of leaf transpiration. The bionic leaf was firstly designed to be composed of a green coating, a water holding layer, a Composite Adsorbent （CS） layer and an adsorption-desorption rate controlling layer. A thermophysical model was established for the bionic leaf, and the dynamic simulation results reveal that the water holding layer is not necessary; a CS of high thermal conductivity should be selected as the CS layer; the adsorp- tion-desorption rate controlling layer could be removed due to the low adsorption-desorption rate of the CS; and when CaC12 mass fraction of the CS reaches 40%; the bionic leaf could simulate the dynamic thermal behavior of the natural leaf. Based on the simulation results, we prepared bionic leaves with different CaC12 content. The thermographies of the bionic leaf and the natural leaf were shot using the Infrared Thermal Imager. The measured average radiative temperature difference between the bionic and natural leaves is less than 1.0 ℃.

关键词： bionic leaf composite sorbent transpiration thermal effect leaf temperature

高活性脐带间充质干细胞干预老年树鼩衰老脾脏的作用与机制

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中国组织工程研究 2025年第19期29卷 4000-4010页

作者：叶丽田川赵晓娟陈梦蝶叶倩倩李强廖珠银李晔朱向情阮光萍何志旭舒莉萍潘兴华贵州医科大学基础医学院免疫学教研室组织工程与干细胞实验中心贵州省贵阳市550004 中国人民解放军联勤保障部队第九二〇医院干细胞与免疫细胞生物医药技术国家地方联合工程实验室云南省细胞治疗技术转化医学重点实验室昆明市干细胞与再生医学重点实验室基础医学实验室云南省昆明市650032 遵义医科大学附属医院儿科学教研室贵州省遵义市563100

背景:脾脏具有储血、造血和免疫功能,随着年龄增长,脾脏结构退变、功能衰退引起免疫系统功能受损,进而加速机体衰老进程,而高活性脐带间充质干细胞治疗树鼩脾脏衰老尚未见报道。目的:探讨高活性脐带间充质干细胞对树鼩脾脏衰老的干预作... 详细信息

背景:脾脏具有储血、造血和免疫功能,随着年龄增长,脾脏结构退变、功能衰退引起免疫系统功能受损,进而加速机体衰老进程,而高活性脐带间充质干细胞治疗树鼩脾脏衰老尚未见报道。目的:探讨高活性脐带间充质干细胞对树鼩脾脏衰老的干预作用及机制。方法:从剖腹产的新生树鼩脐带组织中分离、培养和获得高活性脐带间充质干细胞,三系分化试剂盒检测成脂、成骨、成软骨分化能力,流式细胞术检测细胞周期和表面标志物。以感染复数值分别为100,120,140,160,180,200的吉凯基因绿色荧光蛋白转染第2代高活性脐带间充质干细胞,筛选最佳转染条件;转染后的第4代高活性脐带间充质干细胞尾静脉输注给老年治疗组树鼩,青年对照组和老年模型组不予特殊处理,治疗4个月时取脾脏组织,苏木精-伊红染色观察脾脏组织结构;β-半乳糖苷酶染色检测衰老相关半乳糖苷酶活性;免疫组织化学染色检测p21和p53蛋白表达水平;Ki67和PCNA免疫荧光染色检测细胞增殖活性;免疫荧光染色检测脾脏自噬蛋白分子Beclin1和APG5L/ATG5表达水平;活性氧荧光染色检测脾脏组织的活性氧含量;CD3免疫荧光染色检测总T淋巴细胞比例变化;酶联免疫吸附实验检测脾脏组织白细胞介素1β和转化生长因子β1分泌水平;DAPI复染细胞核观察绿色荧光蛋白标记的高活性脐带间充质干细胞在脾脏组织的分布情况。结果与结论:①高活性脐带间充质干细胞呈核小短梭形、鱼群样生长,G_(0)/G_(1)期占比大,具有向成脂、成骨和成软骨分化潜能。②感染复数为140且转染72 h为吉凯基因绿色荧光蛋白标记树鼩高活性脐带间充质干细胞的最佳条件。③与老年模型组相比,老年治疗组树鼩脾脏组织细胞排列紧密,白髓面积增加(P0.05),脾脏组织衰老相关半乳糖苷酶活性水平降低(Plin1和APG5L/ATG5表达上调(P0.05)。与青年对照组相比,以上检测指标在老年治疗组中均有显著差异(P<0.05)。④冰冻组织切片观察可见老年治疗组树鼩脾脏组织中有绿色荧光蛋白标记的绿色荧光细胞。结果表明:静脉输注高活性脐带间充质干细胞可迁移至脾脏组织,抑制活性氧产生,下调衰老相关蛋白分子表达,诱导细胞自噬,促进细胞增殖,降低慢性炎症,进而改善脾脏组织结构和功能。

关键词：高活性脐带间充质干细胞树鼩脾脏衰老免疫自噬炎症

A review of the protection for the multi-terminal VSC-HVDC grid

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Protection and Control of Modern Power Systems 2019年第1期4卷 251-261页

作者： Bin li Jiawei He ye li Botong li School of Electrical and Information Engineering Tianjin UniversityTianjin300072China

The multi-terminal VSC-HVDC grid is believed to be widely applied in the future power system. The dc line protection is the key technique for operation security and power supply reliability of the dc grid. In this paper, the single-ended protections, namely, the traveling-wave based protection and transient-variable based protection, as well as the pilot protections, mainly including the directional pilot protection and current differential protection, are discussed in detail. With the analyzed protections, the effective main and back-up protection strategy can be configured for the dc line in multi-terminal VSC-HVDC grid.

关键词： Multi-terminal VSC-HVDC grid Traveling-wave based protection Transient-variable based protection Directional pilot protection Current differential protection

Model parameters estimation of aero-engine based on hybrid optimization algorithm

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航空动力学报 2011年第7期26卷 1665-1671页

作者： li Qiu-hong li ye-bo JIANG Dian-wen (College of Energy and Power EngineeringNanjing University of Aeronautics and Astronautics Nanjing 210016 China

A hybrid optimization algorithm for the time-domain identification of multivariable,state space model for aero-engine was presented in this *** optimization procedure runs particle swarm optimization(PSO) and least squares optimization(LSO) "in series".PSO starts from an initial population and searches for the optimum solution by updating ***,it can sometimes run into a suboptimal *** LSO can start from the suboptimal solution of PSO,and get an optimum solution by conjugate gradient *** algorithm is suitable for the high-order multivariable system which has many parameters to be estimated in wide *** optimization algorithm is applied to estimate the parameters of a 4-input 4-output state variable model(SVM) for *** simulation results demonstrate the effectiveness of the proposed algorithm.

关键词： aero-engine state variable model(SVM) particle swarm optimization(PSO) least squares optimization(LSO) hybrid optimization algorithm