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distribution control and formation mechanism of gas inclusions in directionally solidified Al2O3-Er3Al5O12-ZrO2 ternary eutectic ceramic by laser floating zone melting

第十六届中国医师协会神经外科医师年会

作者： di zhao The First Hospital of Hebei Medical University

目的:Objective:To understand the impact of COVID-19 epidemic on the mental health status of ICU practitioners in China,and to explore the relevant factors that may affect the mental health status of first-line medical... 详细信息

关键词： COVID-19 ICU practitioners mental health SCL-90 intervening measure

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Journal of Materials Science & Technology 2021年第7期66卷 21-27页

作者： Haijun Su Yuan Liu Qun Ren Zhonglin Shen Haifang Liu di zhao Guangrao Fan Min Guo Jun Zhang Lin Liu Hengzhi Fu Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518057China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an710072China

distribution control and formation mechanism of gas inclusions formed in directionally solidified Al2O3-Er3Al5O12-ZrO2 eutectic ceramic rods are explored during laser floating zone melting. In atmospheric environment, highly-dense bubble-free eutectic rods are well fabricated at low solidification rate(dification rate is in the range of 25-50 μm/s,but produce continuously at higher solidification rates(100-200 μm/s). The gas inclusions exhibit an elongated finger-like pattern along the growth direction, which of the maximum value of diameter first increases and then decreases with increasing the solidification rate. Meanwhile, the volume fraction of gas inclusions increased gradually with the solidification rate. Based on the effect of surface tension gradient, heterogeneous nucleation of gas bubbles is evaluated to be the primary formation mechanism of gas inclusions.

关键词： directional solidification Gas inclusions Eutectic oxide Laser floating zone melting Formation mechanism

Outcomes of microsurgical clipping vs coil embolization for ruptured aneurysmal subarachnoid hemorrhage

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Outcomes of microsurgical clipping vs coil embolization for ...

Extractive desulfurization of fuel oil with metal-based ionic liquids

第十五届中国医师协会神经外科医师年会

作者： di zhao The First Hospital of Hebei Medical University

＜正＞目的:Aneurysmal subarachnoid hemorrhage （SAH） is a complex neurovascular syndrome with high disability and *** patients may be managed with surgical clipping or coil *** this study,we provided a real-world analysis of the outcome and prognostic factors of aneurysmal SAH in patients treated with coil embolization or microsurgical clipping.

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Chinese Chemical Letters 2015年第9期26卷 1169-1173页

作者： Teng-Jie Ren Juan Zhang Yan-Hui Hu Jun-Pan Li Meng-Shuai Liu di-Shun zhao College of Chemistry and Pharmaceutical Engineering Hebei University of Science and Technology The Academy of Fundamental and Interdisciplinary Science Harbin Institute of Technology

Several metal-based ionic liquids（ILs） were synthesized and used as extractants for the desulfurization of dibenzothiophene（DBT） in simulated fuel *** effects of several anion and metal ions,n（ILs）/n（metal） as mole ratio,V（IL）/V（oil） and extractive times on the removal ratio of DBT were investigated in *** results showed that[BMIM]HSO4/FeCl3（BMIM was short for l-butyl-3-methyl imidazole）was superior to the other ILs for the extractive desulfurization.A total of 100%of DBT was removed at room temperature in 5 min with V[BMIM]HSO4/Fecl3/Voil = 1：*** extractive activity of[BMIM]HSO4/FeCl3 IL did not change almost after five *** desulfurization of different sulfur compounds and commercial diesel fuel oil were also *** removal ratios of the sulfur compounds as the reaction substrates were all over 90%and the sulfur content of commercial diesel oil decreased to120 ppm from 12,400 ppm.

关键词： Ionic liquids Extractive desulfurization [BMIM]HSO4/FeCl3 dibenzothiophene

Single-Atom Protecting Group for on-Surface Synthesis of Graphdiyne Nanowires

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Chinese Journal of Chemical Physics 2019年第5期32卷 620-624页

作者： Huan Shan Ya-hui Mao Ai-di zhao Hefei National Laboratory for Physical Sciences at the Microscale Synergetic Innovation Center of Quantum Information & Quantum Physics Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

On-surface synthesis of semiconducting graphdiyne nanowires usually suffer severe side reactions owing to the high reactivity of the butadiynylene units at noble metal surfaces,limiting the production of isolated nanowires. In this work, we report the high-yield synthesis of branchless graphdiyne nanowires [-C≡C-Ph2-C≡C-]nvia on-surface Ullmann coupling of 1,4-bis（4-bromophenyl）-1,3-butadiyne molecules with chemical vapor deposition ***-contact atomic force microscopy with single-bond resolution reveals that single gold adatoms act as effective protecting groups for butadiynylene units by forming Au-π ligand bonds, preventing unwanted branched coupling reactions and enabling the synthesis of ultralong isolated graphdiyne nanowires. This study will stimulate further investigation on the role of various surface adatoms in protecting on-surface reactions.

关键词： On-surface synthesis Graphdiyne Ullmann coupling Protecting group Atomic force microscopy

Improved Corrosion Resistance in AZ61 Magnesium Alloys Induced by Impurity Reduction

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 225-232页

作者： Yan Dai Xian-Hua Chen Tao Yan Ai-Tao Tang di zhao Zhu Luo Chun-Quan Liu Ren-Ju Cheng Fu-Sheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing 400045China Chongqing Academy of Science and Technology Chongqing 401123China

The effect of impurity element Fe on corrosion behavior of AZ61 magnesium alloys in various states has been investigated by immersion test and hydrogen evolution measurements in 3.5% sodium chloride *** corrosion rate is found to relay on the impurity Fe concentration in the alloys and decreases with decreasing Fe *** Fe content drops from 150 ppm to 10 ppm,the corresponding corrosion rates under as-cast and solution treatment conditions are reduced from 8.54 mm/a and 8.61 mm/a to 2.54 mm/a and 0.21 mm/a,*** corrosion pattern of the AZ61 alloys is the localized corrosion,and the galvanic couples are formed among the impurity particles,second-phase particles and the *** Fe impurity particles tend to act as main cathodic to form micro-galvanic cell with the α-Mg matrix,which is harmful for corrosion resistance of AZ61 alloy.

关键词： AZ61 magnesium alloy Impurity Fe Corrosion rate

Microstructure evolution and solidification behaviour of ZrB_(2)-SiC composite ceramics fabricated by laser surface zone-melting

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Journal of Materials Science & Technology 2024年第23期190卷 145-154页

作者： Zhuo Zhang Xiping Song Haijun Su Hao Jiang di zhao Xiang Li Dong Dong Yuan Liu Zhonglin Shen Yinuo Guo Peixin Yang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China

Microstructure evolution and solidification behaviour of ZrB_(2)-SiC composite ceramics fabricated by laser surface zone-melting were *** coarsening at high scanning speed and mi-crostructure refining after turning off the laser was observed due to the changes in the solidification *** solidification behaviour from bottom to top of the molten pool was studied,where there are some coarsen eutectic bands caused by the secondary heating of the melting pool on the solidified eu-tectic zone in the molten *** deviation of melt composition from the eutectic ratio due to the volatilization of SiC can form a coarse primary ZrB_(2) phase among fine eutectic structure(single-phase instability),and the constitutional supercooling due to the accumulation of impurity elements can form coarse eutectic dendrites among fine eutectic structure(two-phase instability).Both single-phase insta-bility and two-phase instability are adverse to the mechanical properties,which should be prevented by adjusting the composition of raw materials and the solidification process.

关键词： ZrB_(2)-SiC Eutectic composite ceramics Microstructure evolution Solidification behaviour Laser surface zone-melting

The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

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Journal of Environmental Sciences 2019年第5期31卷 121-134页

作者： Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue di zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Shenyang Academy of Environmental Sciences Shenyang Environmental Monitoring Centre Chinese Research Academy of Environmental Sciences

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang.

关键词： Volatile organic compounds Source apportionment Photochemical ozone formation Field measurement

Adipose tissue dysfunction and the pathogenesis of metabolic syndrome

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World Journal of Hypertension 2013年第3期3卷 18-26页

作者： di zhao Hui Liu division of Hypertension the Second Hospital Affiliated to Zhengzhou University division of Endocrinology Luoyang Central Hospital Affiliated to Zhengzhou University

Metabolic syndrome is a growing research area. The underlying mechanisms of metabolic syndrome are still not very clear. Insulin resistance, obesity, inflammation and oxidative stress may play an important role in the pathogenesis of metabolic syndrome. The role of adipose tissue dysfunction is emphasized during the development of obesity. Adipose tissue is identified as a complex endocrine organ and its metabolic functions extend well beyond the classical actions of thermoregulation and of storage and release of fatty acids. Chronic low-grade inflammation activated by the immune system in adipose tissue is a key contributing factor to type 2 diabetes mellitus and cardiovascular diseases. Visceral obesity results in cell autonomous impairment in insulin signaling that leads to insulin resistance. Chronic inflammation in adipose tissue has gained acceptance as a lead promoter of insulin resistance in obesity. Furthermore, obesity creates oxidativestress conditions in adipose tissue that not only correlates with insulin resistance but is also causative in its development. Oxidative stress may be a mechanistic link between several components of metabolic syndrome and cardiovascular diseases, through its role in inflammation and its ability to disrupt insulin-signaling. The study around adipose tissue dysfunction will help to understand the pathogenesis of metabolic syndrome and may bring effective therapy in treatment of metabolic syndrome related diseases. Therefore, this review mainly focuses on the roles of adipose tissue dysfunction in inflammation, insulin resistance, and oxidative stress in the pathogenesis of metabolic syndrome.

关键词： Metabolic syndrome Adipose tissue dysfunction Insulin resistance Inflammation Oxidative stress