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Physical and chemical processes of wintertime secondary nitrate aerosol formation

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 348-361页

作者： qi ying Zachry Department of Civil Engineering Texas A&M UniversityCollege StationTX 77845-3136USA

The UCD/CIT model was modified to include a process analysis(PA)scheme for gas and particulate matter(PM)to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM_(2.5)/PM_(10) Air Quality Study(CRPAQS)where detailed measurements of PM components are available at a few *** nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4μg·m^(-3)·d^(-1) during the study *** secondary nitrate formation rate in rural areas is lower due to lower NO_(2).In the afternoon hours,near-surface temperature can be high enough to evaporate the particulate *** the nighttime hours,both the gas phase N_(2)O_(5) reactions with water vapor and the N_(2)O_(5) heterogeneous reactions with particle-bound water are important for secondary nitrate *** N_(2)O_(5) reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1μg·m^(-3)·d^(-1) and are more significant in the rural areas where the O3 concentrations are high at *** general,vertical transport during the day moves the nitrate formed near the surface to higher *** the stagnant days,process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration.

关键词： secondary nitrate aerosol N_(2)O_(5)heterogeneous reaction process analysis

Temperature stability and fracture toughness of Nd-Fe-B magnets

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Rare Metals 2006年第Z1期25卷 637-640页

作者： LI ying qi Yuxuan LI Xiumei Tianjin Navigation Instrument Institute Tianjin 300131 China Tianjin Navigation Instrument Institute Tianjin 300131 China Division of Functional Materials Central Iron & Steel Research Institute Beijing 100081 China

Temperature stability and toughness of magnets are very important properties especially for application in motor. In this paper, it is found that temperature stability and toughness of magnets are improved when Fe is substituted with Co and heavy rare earth is substituted for Nd in part and suitable rich B grain-boundary phase is added. In addition, heavy rare earth substitution decreases the remanence temperature coefficient greatly, but has a little effect on Curie temperature of the magnets, which is beneficial to Nd-Fe-B magnets for the application in motor.

关键词： Nd-Fe-B permanent magnet temperature stability mechanical characteristic motor

Stable high-dimensional solitons in nonlocal competing cubic-quintic nonlinear media

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Communications in Theoretical Physics 2022年第2期74卷 19-27页

作者： qi-ying Zhou Hui-jun Li Institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhuaZhejiang 321004China

We find and stabilize high-dimensional dipole and quadrupole solitons in nonlocal competing cubic-quintic nonlinear *** adjusting the propagation constant,cubic,and quintic nonlinear coefficients,the stable intervals for dipole and quadrupole solitons that are parallel to the x-axis and those after rotating 45°counterclockwise around the origin of coordinate are *** the dipole solitons and those after rotation,their stability is controlled by the propagation constant,the coefficients of cubic and quintic *** stability of quadrupole solitons is controlled by the propagation constant and the coefficient of cubic nonlinearity,rather than the coefficient of quintic nonlinearity,though there is a small effect of the quintic nonlinear coefficient on the *** proposal may provide a way to generate and stabilize some novel high-dimensional nonlinear modes in a nonlocal system.

关键词： nonlocal media competing cubic-quintic nonlinearity dipole soliton quadrupole soliton

Spatial and Temporal Variations in the Atmospheric Age Distribution of Primary and Secondary Inorganic Aerosols in China

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Engineering 2023年第9期28卷 117-129页

作者： Xiaodong Xie qi ying Hongliang Zhang Jianlin Hu Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyNanjing University of Information Science&TechnologyNanjing 210044China Zachry Department of Civil Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Environmental Science and Engineering Fudan UniversityShanghai 200438China

The aging timescale of particles is a key parameter in determining their impacts on air quality,human health,and *** this study,a one-year simulation of the age distributions of the primary and secondary inorganic fine particulate matter(PM_(2.5))components was conducted over China using an age-resolved Community Multiscale Air Quality(CMAQ)*** results indicate that primary PM_(2.5)(PPM)and ammonium mainly originate from fresh local emissions,with approximately 60%-80%concentrated in 0-24 h age bins in most of China throughout the *** average age is about15-25 h in most regions in summer,but increases to 40-50 h in southern region of China and the Sichuan Basin(SCB)in *** is more aged than PPM,indicating an enhanced contribution from regional *** sulfate with atmospheric age>48 h account for 30%-50%of total sulfate in most regions and seasons,and the concentrations in the>96 h age bin can reach up to 15μg·m-3 in SCB during *** seasonal variations occur in the Yangtze River Delta,Pearl River Delta,and SCB,with highest average age of 60-70 h in winter and lowest of 40-45 h in *** average age of nitrate is 20-30 h in summer and increases to 40-50 h in *** enhanced deposition rate of nitric acid vapor combined with the faster chemical reaction rate of nitrogen oxides leads to a lower atmospheric age in ***,on pollution days,the contributions of old age bins(>24 h)increase notably for both PPM and secondary inorganic aerosols in most cities and seasons,suggesting that regional transport plays a vital role during haze *** age information of PM_(2.5),provided by the age-resolved CMAQ model,can help policymakers design effective emergent emission control measures to eliminate severe haze episodes.

关键词： Atmospheric age PM_(2.5) CMAQ model Control strategy

Hutchinson-Gilford Progeria Syndrome and its Relevance to Cardiovascular Diseases and Normal Aging

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Biomedical and Environmental Sciences 2013年第5期26卷 382-389页

作者： qi ying Chun XIE Xiao Hua First Department of Comprehensive Surgery in South Building Chinese PLA General Hospital

Hutchinson-Gilford progeria syndrome(HGPS,OMIM176670)is an extremely rare,sporadic genetic syndrome with a reported prevalence of one in4-8million children *** April2012,the total number of known living children with ... 详细信息

关键词： HGPS Hutchinson-Gilford Progeria Syndrome and its Relevance to Cardiovascular Diseases and Normal Aging

Leptin administration exacerbates thioacetamide-induced liver fibrosis in mice

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World Journal of Gastroenterology 2005年第31期11卷 4822-4826页

作者： Kai Dai Jun-ying qi De-ying Tian Department of Infectious Diseases Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To investigate the effects of leptin administration on liver fibrosis induced by thioacetamide （TAA）. METHODS： Twenty-four male C57BI/6 mice were randomly allocated into four groups, which were intra-peritoneally given saline （2 mL/kg）, leptin （1 mg/kg）, TAA （200 mg/kg）, TAA （200 mg/kg） plus leptin （1 mg/kg） respectively, thrice a week. All mice were killed after 4 wk. The changes in biochemical markers, such as the levels of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in serum and superoxide dismutase （SOD）, malondialdehyde （MDA） in liver were determined. For histological analysis, liver tissues were fixed with 10% buffered formalin, embedded with paraffin. Hematoxylin-eosin （HE） staining and picric acid-Sirius red dyeing were performed. The level of α1（I） procollagen mRNA in liver tissues was analyzed by RT-PCR. RESULTS： Apparent liver fibrosis was found in TAA group and TAA plus leptin group. Compared to saline group, the levels of ALT and AST in serum and MDA in liver increased in TAA group （205.67±27.69 U/L vs 50.67±10.46 U/L, 177.50±23.65 U/L vs76.33±12.27 U/L, 2.60±0.18 nmol/mg pro vs 1.91±0.14 nmol/mg pro, P〈0.01） and in TAA plus leptin group （256.17±22.50 U/L vs 50.67±10.46 U/L, 234.17±27.37 U/L vs76.33±12.27 U/L, 2.97±0.19 nmol/mg pro vs 1.91±0.14 nmol/mg pro, P〈0.01）. The level of SOD in livers decreased （51.80±8.36 U/mg pro vs 81.52±11.40 U/mg pro, 35.78±6.11 U/mg pro vs81.52± 11.40 U/mg pro, P〈0.01） and the level of α1（I） procollagen mRNA in liver tissues also increased （0.28±0.04 vs0.11± 0.02, 0.54±0.07 vs0.11±0.02, P〈0.01）. But no significant changes were found in leptin group and saline group. Compared to TAA group, ALT, AST, MDA, and α1（I） procollagen mRNA and grade of liver fibrosis in TAA plus leptin group increased （256.17±22.50 U/L vs 205.67± 27.69 U/L, P〈0.05; 234.17±27.37 U/L vs 177.50±23.65 U/L, P〈0.05; 2.97±0.19 nmol/mg pro vs 2.60±0.18 nmol/mgpro, P〈0.05, 0.54±0.07 vs0.28±0.04, P〈0.01, 3.17 vs 2.00, P〈0.05）, and

关键词： Liver fibrosis Leptin α1(I) procollagen

Preparation of rare-earth-modified medical stone powders and their application as conductive fillers

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 260-266页

作者： Li-ying qi Su-e Hao Tian-cheng Sun School of Chemistry and Chemical Engineering Harbin Institute of Technology

Traditional metal conductive fillers are expensive and prone to oxidation. Thus, the development of new conductive powders as fillers is urgently needed. A novel gaseous penetration technology was adopted to prepare La-doped medical stone powders(La-MSPs), which are inexpensive mesoporous materials, as a new kind of conductive filler material. The prepared La-MSPs attained a resistivity of 450 ?·m and were used as a filler to prepare conductive coatings with epoxy resin as the resin matrix. The influence of the La-MSPs dosage on the resistance and hardness of the coatings was also determined. The resistance and the hardness both decreased with increasing filler dosage. Finally, the optimum recipe of the conductive coatings with the most suitable fillers dosage(55 wt%) was obtained. The hardness and resistance of the coatings with 55 wt% La-MSPs were HV 4 and 5.5 × 10~7 ?, respectively.

关键词： chemical engineering conductive materials rare earths medical stone powders gaseous penetration technology

Gold-catalyzed intermolecular reaction of ynamides with 3-indolyl azides via an unexpected 1,2-alkyl migration

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Science Bulletin 2017年第17期62卷 1201-1206页

作者： Bo Zhou ying-qi Zhang Xin Liu Long-Wu Ye State Key Laboratory of Physical Chemistry of Solid Surfaces and The Key Laboratory for Chemical Biology of Fujian Province College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A gold-catalyzed intermolecular reaction of ynamides with 3-indolyl azides via the presumable α-imino gold carbenes has been developed, providing an alternative and efficient way for the synthesis of valuable 3-amino-β-carbolines in generally good to excellent yields. Importantly, this new protocol involves an unexpected 1,2-alkyl migration pathway.

关键词： Gold Heterocycles Migration Cyclization Tandem reaction

Underlying mechanisms of mindfulness meditation:Genomics,circuits,and networks

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World Journal of Psychiatry 2022年第9期12卷 1141-1149页

作者： ying-qi Gu Yi Zhu Department of Psychology Zhejiang Sci-Tech UniversityHangzhou 310018Zhejiang ProvinceChina School of Psychology Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Department of Psychology The First Affiliated Hospital of Hainan Medical UniversityHaikou 570102Hainan ProvinceChina

Understanding neuropsychological mechanisms of mindfulness meditation(MM)has been a hot topic in recent *** review was conducted with the goal of synthesizing empirical relationships via the genomics,circuits and networks between MM and mental *** describe progress made in assessing the effects of MM on gene expression in immune cells,with particular focus on stressrelated inflammatory markers and associated biological *** then focus on key brain circuits associated with mindfulness practices and effects on symptoms of mental disorders,and expand our discussion to identify three key brain networks associated with mindfulness practices including default mode network,central executive network,and salience *** research efforts need to be devoted into identifying underlying neuropsychological mechanisms of MM on how it alleviates the symptoms of mental disorders.

关键词： Mindfulness meditation Gene expression Neural circuits Neural networks