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Coarsening and Age Hardening Behaviors of γ' Particles in GH742 During High Temperature Treatment

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Journal of Iron and Steel Research International 2009年第5期16卷 81-86页

作者： li Hong-yu SONG xi-ping WANG yan-li CHEN Guo-liang State Key Lab for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The coarsening and ageing hardening behaviors of γ′ particles in superalloy GH742 have been investigated by field emission scanning electron microscopy （FESEM）, coarsening kinetics calculation and microhardness testing when ageing at 1 050, 950 and 900 ℃ for different time. The cube of γ′ particle size and ageing time follows a linear law as predicted by LSW theory. The particle size distributions give better fit to the LSW theoretical distribution. The activation energy for γ′ coarsening is accurately determined to have 245. 06±14.42 kJ/mol when considering the effect of temperature on the solution concentrations in matrix. Based on the activation energy, the coarsening kinetics of γ′ particle is predicted as r^-t^3=7.35×10^15 Ce/T exp -（245060±14420）/RT *** microhardness studies indicate that microhardness decreases rapidly with increasing the ageing temperature and it has a maximum value corresponding to a critical particle size beyond which the microhardness increase stalls with increasing the ageing time.

关键词： superalloy γ′ particle coarsening kinetics activation energy microhardness

Spontaneous dislocation of a toric implantable collamer lens resulting in corneal endothelial decompensation:a case report and review of the literature

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International Journal of Ophthalmology(English edition) 2023年第1期16卷 135-138页

作者： li Zhang yan-xi li Chun-yan Lei lin Wang Mei-xia Zhang Sichuan University West China Hospital Chengdu 610041Sichuan ProvinceChina

Dear Editor We present a case of spontaneous dislocation of a toric implantable collamer lens(TICL)resulting in corneal endothelial decompensation 8y after *** 2006,by helping people take off their glasses,the Visian TICL(Staar Surgical Co,Monrovia,CA,USA)have gained popularity in *** complications of intraocular pressure(IOP)elevation,cataract formation and endothelial damage exist as relevant problems,implantable collamer lens(ICL)implantation has been generally accepted as a viable option to correct moderate to high ametropia[1-2].

关键词： dislocation implantation glasses

Distribution of avian influenza viruses according to environmental surveillanee during 2014-2018, China

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Infectious Diseases of Poverty 2021年第3期10卷 99-100页

作者： Hong Bo Ye Zhang li-Bo Dong Jie Dong xi-yan li xiang Zhao Zi li Yue-Long Shu Da-yan Wang Nation al Institute for Viral Disease Control and Preve ntion Chinese Center for Disease Control and PreventionWHO Collaborating Center for Reference and Research On InfluenzaKey Laboratory for BiosafetyNational Health CommissionBeijingChina 不详

Background:Recurrent infections of animal hosts with avian influenza viruses(AIVs)have posted a persistent *** is very important to understand the avian influenza virus distribution and characteristics in environment associated with poultry and wild *** aim of this study was to analyze the geographic and seasonal distributions of AIVs in the 31 provinces,municipalities and autonomous region(PMA)of China,compare the AIVs prevalence in different col-lecting sites and sampling types,analyze the diversity of AIVs subtypes in environment.

关键词： Avian influenza virus live poultry market Environment Surveillanee

A novel three-step approach to separate cathode components for lithium-ion battery recycling

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Rare Metals 2021年第6期40卷 1431-1436页

作者： Yun Zhao ling-Zhe Fang Yu-Qiong Kang li Wang Yu-Nan Zhou xin-Yi liu Tao li yan-xi li Zheng liang Zhe-Xu Zhang Bao-Hua li Engineering Laboratory for Next Generation Power and Energy Storage Batteries Graduate School at ShenzhenTsinghua UniversityShenzhen 518055China Department of Chemistry and Biochemistry Northern Illinois UniversityDekalb 60115USA Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Materials Science and Engineering Stanford UniversityStanford 94305USA

lithium-ion batteries(liBs)represent efficient energy storage technology that can help to alleviate fossil fuel-based CO_(2) ***,liBs are being applied extensively in consumer electronics and electric vehicles,but because of limited resources,there is an urgent need for spent liB recycling *** complexity of liBs,especially the electrode part,makes it difficult to achieve precision separations for each single component from the used electrode with low ***,we propose a three-step treatment for the separation of cathode *** detail,detaching of the current collector from the cathode is accomplished by the solvent method,which was found to be an ideal strategy compared with previous ***,a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride(PVDF)from other cathode components by dissolution with *** separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good *** anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory-and industrialscale *** of binder and development of novel binders,which can be easily recycled for sustainable liBs,are fruitful areas for further research.

关键词： lithium-ion batteries Recycling Electrode separation PVDF Thermal treatment Polymer solution

Wound Healing Assay Using Microfluidic Channels

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Chemical Research in Chinese Universities 2012年第3期28卷 472-476页

作者： xi yan-li WANG Shu-tao SU Bin HA Qing NIU Feng-lan NIE Fu-qiang School of Public Health Jinlin UniversityChangehun 130021P.R.China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeoTng 100190P.R.China

An approach was described to produce a wound area in vitro using laminar flow technique to selectively remove cells in micro fluidic channels. Cell migration which plays an important role in the process of wound healing can be observed dynamically by this method. In order to prove our system, we have studied its properties by injecting NIH-3T3 cells into main channel and added several reagents to observe the mediatory influence. The results reveal that fibroblast growth factor-2（FGF-2）, insulin-like growth factor 1（IGF-Ⅰ）, platelet-derived growth factor BB（PDGF-BB） and ascorbic acid（Vc） groups can promote cell migration compared with the control group. But the average migration distance was diminished in dexamethasone group. It can be concluded that this system can be used to analyze the process of wound healing.

关键词： Wound healing Cell migration Microfluidic channel

Sp1 contributes to overexpression of stanniocalcin 2 through regulation of promoter activity in colon adenocarcinoma

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World Journal of Gastroenterology 2019年第22期25卷 2776-2787页

作者： Ji-Bin li Zhe-xian liu Rui Zhang Si-Ping Ma Tao lin yan-xi li Shi-Hua yang Wan-Chuan Zhang Yong-Peng Wang Department of Colorectal Surgery Cancer Hospital of China Medical University Liaoning Cancer Hospital & Institute

BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the role of its overexpression in the development of COAD remains unclear. AIM To evaluate the regulation mechanism of STC2 overexpression in COAD. METHODS The expression of STC2 in COAD was assessed by TCGA COAD database and GEO (GSE50760). Methylation level of the STC2 promoter was evaluated with beta value in UALCAN platform, and the correlation between STC2 expression and survival rate was investigated with TCGA COAD. Transcription binding site prediction was conducted by TRANSFAC and LASAGNA, and a luciferase reporter system was used to identify STC2 promoter activity in several cell lines, including HEK293T, NCM460, HT29, SW480, and HCT116. Western blotting was performed to evaluate the role of Sp1 on the expression of STC2. RESULTS The central finding of this work is that STC2 is overexpressed in COAD tissues and positively correlated with poor prognosis. Importantly, the binding site of the transcription factor Sp1 is widely located in the promoter region of STC2. A luciferase reporter system was successfully constructed to analyze the transcription activity of STC2, and knocking down the expression of Sp1 significantly inhibited the transcription activity of STC2. Furthermore, inhibition of Sp1 remarkably decreased protein levels of STC2. CONCLUSION Our data provide evidence that the transcription factor Sp1 is essential for the overexpression of STC2 in COAD through activation of promoter activity. Taken together, our finding provides new insights into the mechanism of oncogenic function of COAD by STC2.

关键词： Transcription factor Sp1 Stanniocalcin 2 Overexpression Promoter activity Colon adenocarcinoma

沥青混合料的变速拌和功率测试与拌和流变模型

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交通运输工程学报 2016年第3期16卷 1-7页

作者：延西利田辉黎延喜乐游庆龙艾涛长安大学公路学院陕西西安710064 陕西省榆林公路管路局陕西榆林719000 长安大学材料科学与工程学院陕西西安710064

为了定量评价沥青混合料的和易性与深化认识其强度构成的演变机理,基于沥青混合料的常规拌和设备,自行开发了一种变速拌和功率测试装置V-P-Mixer,进行了沥青混合料的拌和流变特性试验。针对不同沥青用量(0~8%)的AC-13C型沥青混合料,在... 详细信息

为了定量评价沥青混合料的和易性与深化认识其强度构成的演变机理,基于沥青混合料的常规拌和设备,自行开发了一种变速拌和功率测试装置V-P-Mixer,进行了沥青混合料的拌和流变特性试验。针对不同沥青用量(0~8%)的AC-13C型沥青混合料,在不同拌和温度(130℃~170℃)和不同拌和速率(20~50r·min^(-1))下进行了拌和功率测试,绘制了功率-速率流变图,建立了黏塑性拌和流变模型,并以拌和黏度的倒数定义了和易性指数。分析结果表明:拌和消耗的电流、电压和有功功率的波动误差分别为2.25%、0.11%和5%,重复再现误差为0.25%,测试数据稳定、可靠,可用来表征沥青混合料的拌和功率;拌和流变模型服从线性的Bingham黏塑性模型,流变直线的斜率可以表征沥青混合料的拌和黏度,定义斜率的倒数为和易性指数;拌和温度每升高10℃可降低拌和黏度和提高和易性指数10%~20%;沥青用量的增加会增大拌和的黏度和阻力,每增加1%降低和易性指数5%~25%;从强度构成的演变机理来看,碎石决定了内在塑性极限,沥青决定了黏性强度。

关键词：路面材料沥青混合料拌和速率拌和功率流变模型和易性指数

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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Nano-Micro Letters 2025年第3期17卷 340-354页

作者： li An Jianyi li Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian xi * Zhichuan JXu Chun‑Hua yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is *** substituting Fe content influences both current change tendency and surface reconstruction ***_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based ***,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Ameliorative Effects of Brassinosteroid on Excess Manganese-Induced Oxidative Stress in Zea mays L. Leaves

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Agricultural Sciences in China 2009年第9期8卷 1063-1074页

作者： WANG Hai-hua, FENG Tao, PENG xi-xu, yan Ming-li, ZHOU Ping-lan and TANG xin-ke School of life Sciences, Hunan University of Science and Technology, xiangtan 411201, P.R.China School of life Sciences Hunan University of Science and Technology Xiangtan 411201 P.R.China

Manganese （Mn） is becoming an important factor limiting crop growth and yields especially on acid soils. The present study was designed to explore the hypothesis that brassinosteroid application can enhance the tolerance of maize （Zea mays L.） to Mn stress and if so, whether or not the mechanism underlying involves regulation of antioxidative metabolism in leaves. The effects of 24-epibrassinosteroid （EBR） on the growth, photosynthesis, water status, lipid peroxidation, accumulation of reactive oxygen species, and activities or contents of antioxidant defense system in maize plants under Mn stress were investigated by a pot experiment. At supplemented Mn concentrations of 150-750 mg kg^-1 soil, the growth of plants was inhibited in a concentration-dependent manner. The semi-lethal concentration was 550 mg Mn kgq soil. Foliage application with 0.1 mg L^-1 EBR significantly reduced the decrease in dry mass, chlorophyll content, photosynthetic rate, leaf water content, and water potential of plants grown in the soil spiked with 550 mg kg^-1 Mn. The oxidative stress caused by excess Mn, as reflected by the increase in malondialdehyde （MDA） content and lipoxygenase （LOX, EC 1.***.11.12） activity, accumulation of superoxide radical and H2O2, was greatly decreased by EBR treatment. Further investigations revealed that EBR application enhanced the activities of superoxide dismutase （SOD, EC 1.***.1.1）, peroxidase （POD, EC 1.***.1.7）, catalase （EC 1.***.1.6）, ascorbate peroxidase （APX, EC 1.11. 1.11）, dehydroascorbate reductase （DHAR, EC 1.***.5.1）, and glutathione reductase （GR, EC 1.***.4.2）, and the contents of reduced ascorbate and glutathione, compared with the plants without EBR treatment. It is concluded that the ameliorative effects of EBR on Mn toxicity are due to the upregulation of antioxidative capacity in maize under Mn stress.

关键词： excess manganese brassinosteroid oxidative stress antioxidant defense system maize (Zea mays L.)