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Characterization and Three-dimensional Structural Modeling of Humic Acid via Molecular Mechanics and Molecular Dynamic Simulation

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Chemical Research in Chinese universities 2013年第6期29卷 1180-1184页

作者： ZHAO Nan l.u) Yi-zhong lI Guang-jun College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R.China School of Chemistry and Environment Beijing University of Aeronautics and AstronauticsBeijing 100191 P.R.China

The humic acid（HA） sample obtained from the al.uvial soil was characterized by elemental composition, pyrolysis gas chromatography-mass spectrometry（Py-GC-MS） and solid-state 13C nuclear magnetic resonance （13C NMR） spectroscopy. There is high fat content and a few nitrogen-containing functional groups in HA. Py-GC-MS demonstrates the characterization and structural identification of HA. One long list of identified pyrolysis products was proposed for the construction of conceptual model of HA. Solid-state 13C NMR data indicate there are higher values of alkyl-C, O-alkyl-C and aryl-C in HA. The elemental composition, structural carbon distribution and l3C NMR spectroscopy of simulated HA are consistent with those of experimental HA. HyperChem was used to simulate the three-dimensional molecular structure of the monomer, which was optimized by the molecular mechanics of the optimized potential for liquid simulations（OPlS） force field and molecular dynamics simulation to get the stable and balanced conformation. The deprotonation process study depicts that the degree of ionization of HA gets deeper, while the electronegativity of HA and the energy of van der Waals（vdW） increase. Moreover, the 3D structure of humic acid with -4 charges is the most stable. The deprotonation process is an endothermic process.

关键词： Al.uvial soil Humic acid Conceptual model Elemental analysis Pyrolysis gas chromatography-mass spectrometry(Py-GC-MS) 13C nuclear magnetic resonance(13C NMR) Molecular simulation Three-dimensional structure Optimized potential for liquid simulatio

Genes associated with Alzheimer's disease affecting ischemic neurodegeneration of the hippocampal CA3 region

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Neural Regeneration Research 2021年第7期16卷 1392-1393页

作者： Ryszard Pluta Marzena ułamek-Kozioł laboratory of Ischemic and Neurodegenerative Brain Research Mossakowski Medical Research CentrePolish Academy of SciencesWarsawPoland

Neurodegeneration in the brain after ischemia with reperfusion mimicking the neuropathology of Alzheimer's disease:Brain ischemia with reperfusion,which is one of the main causes of morbidity and mortality in the world,triggers various neuropathological changes characteristic for Alzheimer's disease(AD)such as increased blood-brain barrier permeability,excitotoxicity,necrosis,autophagy,mitophagy,apoptosis,neuroinflammation,amyloid plaques,neurofibrillary tangles,cerebral vessel pathology,and brain atrophy that lead to the death of neurons,deteriorating motor,sensory and cognitive functions(Figure 1)(Kato et al.,1988;Wisniewski et al.,1995;Van Groen et al.,2005;Kocki et al.,2015;ułamek-Koziołet al.,2016,2017,2019).Brain ischemia is recognized as a major contributor to the dysfunction of an aging brain and the development of neurodegenerative diseases,including AD(Pluta,2019).

关键词： Alzheimer ischemia cerebral

Influence of ageing on oil degradation and gassing tendency under high-energy electrical discharge faults for mineral oil and synthetic ester

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High Voltage 2020年第6期5卷 731-738页

作者： l.loiselle u.Mohan Rao I.Fofana Research Chair on the Aging of Power Network Infrastructure(ViAHT) Universitédu QuébecàChicoutimiChicoutimiQCG7H 2B1Canada

In this work, mineral oil and synthetic esters were selected at different ageing factors (based on acidity values). Fresh and aged oils have been subjected to high-energy discharges (repeated 100 breakdowns) to simulate electric faults of highly vulnerable intensity. The intent of this work is to understand the influence of high-energy electric faults on oil degradation and gassing tendency at different ageing conditions. In this study, the influence of the high-energy discharges on degradation and gassing tendency at different ageing factors is reported for mineral oil and synthetic esters. Oil degradation is reported by adopting ultraviolet spectroscopy, turbidity and particle counter as per american society for testing and materials (ASTM) standard test methods. Gassing tendencies and fault gas analysis are understood by dissolved the gas analysis using Duval's triangle and Duval's pentagon methods for mineral and non-mineral oils. It is found that the influence of high-energy discharges on oil degradation is higher in mineral oils to that of the synthetic esters. The intensity of the gassing tendency is higher for ester fluids;however, as per the Duval methods, the faulty conditions are at lower levels as compared to mineral oils.

关键词： synthetic energy high

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cel.ular & Molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat M.u.Demael l.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,MERS-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKu1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

Inquiries and Confession before the Cross： An Interpretation of Wang Guilin＇s My Jerusalem

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Frontiers of literary Studies in China-Selected Publications from Chinese universities 2015年第2期9卷 318-336页

作者： l.u Yan Institute for Trans-cul.ural Studies Beijing Intemational Studies University Beijing 100024China

This essay employs the approach of New Criticism close reading to interpret My Jerusalem by a contemporary Chinese poet, Wang Guilin, from the dialogic perspective of＂I and Thou.＂ From a dimension of faith beyond daily life, the poet narrates his astonishment, historical reflection and spiritual transformation during a visit to Jerusalem. For him, the journey to Jerusalem was also a pilgrimage to a spiritual homeland, self-achievement, and peace and love.

关键词： Jerusalem Bible I and Thou the Cross

A Rapid-Ab/Desorption and Portable Photothermal MIl- 101(Cr) Nanofibrous Composite Membrane Fabricated by Spray-Electrospinning for Atmosphere Water Harvesting

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Energy & Environmental Materials 2023年第1期6卷 111-118页

作者： Ailin li Jian Xiong Ye l.u liming Wang xiaohong Qin Jianyong Yu Key laboratory of Textile Science and Technology of Ministry of Education College of TextilesDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China

MIl-101(Cr)is a promising moisture absorbent for solar-driven water harvesting from moisture to tackle the worldwide water shortage ***,the MIl-101(Cr)powder suffers from a long ab/desorption cycle due to the crystal aggregation caused by its inherent powder ***,we demonstrate a MIl-101(Cr)nanofibrous composite membrane with a nanofibrous matrix where MIl-101(Cr)is monodisperse in the 3D porous nanofibrous matrix through a simple spray-electrospinning *** continuous porous nanofibrous matrix not only offers sufficient sites for MIl-101(Cr)loading but also provides rapid moisture transport channels,resulting in a super-rapid ab/desorption duration of 50 min(including an absorption process for 40 min and a desorption process for 10 min)and multicycle daily water production of 15.9 l kg^(−1) d^(−1).Besides,the MIl-101(Cr)nanofibrous composite membrane establishes a high solar absorption of 92.8%,and excellent photothermal conversion with the surface temperature of 70.7°C under one-sun *** addition,the MIl-101(Cr)nanofibrous composite membrane shows excellent potential for practical application due to its flexibility,portability,and use *** work provides a new perspective of shortening MOF ab/desorption duration by introducing a porous nanofibrous matrix to improve the specific water production for the solar-driven ab/desorption water harvesting technique.

关键词： electrospinning fast vapor transport MIl-101(Cr) MOF composite membrane solar-driven moisture harvesting

Sewage sludge ditch for recovering heavy metals can improve crop yield and soil environmental quality

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Frontiers of Environmental Science & Engineering 2021年第2期15卷 65-75页

作者： Xianke lin xiaohong Chen Sichang li Yangmei Chen Zebin Wei Qitang Wu Key laboratory of Soil Environment and Waste Reuse in Agricul.ure of Guangdong Higher Education Institutes College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Key laboratory of the Pearl River Estuarine Dynamics and Associated Process Regulation Ministry of Water ResourcesPearl River Hydraulic Research InstitutePearl River Water Resource CommissionGuangzhou 510611China

The treatment and disposal of municipal sewage sludge(MSS)is an urgent problem to be resolved in many *** using the nutrients within MSS to increase crop yield and enhance the fertility of poor soil could contribute to achieving sustainable *** indirect use of MSS in ditches alongside Pennisetum hybridum plants was studied in field plots for 30 months and the contents of heavy metals and macronutrients were monitored in soil,sludge and plant *** found that the yield of *** was significantly increased by 2.39 to 2.80 times and the treated plants had higher N content compared with no *** addition,the organic matter(OM)and N contents in the planted soil increased significantly compared with the initial *** OM content in the planted soil of the MSS treatment was 2.9 to 5.2 times higher than that with no sludge,and N increased by 2.0 to 3.8 ***,MSS had no significant effect on the N,P and K contents in the soil at the bottom of the MSS ditch,and the content of heavy metals(Cd,Pb,Cu and Zn)were also within the safe ***,the moisture content and phytotoxicity of MSS after this indirect use were reduced and the heavy metal contents changed little,which is favorable to the further disposal of recovered ***,this indirect use of MSS is beneficial to agricul.ural production,soil quality and environmental sustainability.

关键词： Municipal sewage sludge Indirect use Heavy metals Macronutrients Pennisetum hybridum

In-situ nitrogen fate in the vadose zone of different soil types and its implications for groundwater quality in the Huaihe River Basin,China

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Acta Geochimica 2020年第3期39卷 281-290页

作者： Rongfu li xiaohong Ruan Tianhai Ma Ying Bai Congqiang l.u MOE Key laboratory of Surficial Geochemistry Nanjing UniversityNanjing 210023China Department of Water Science School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China Jinling Institute of Nanjing university Nanjing 210089China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China

This paper focused on nitrate fate in the vadose zone(VZ)and its implications for groundwater vulnerability under different soil types in the agricul.ural area of Huaihe River Basin,*** compositions of nitrate(δ15N andδ18O)along with NO3-and Cl-concentrations were determined in the VZ-shallow groundwater continuum beneath silty-loam and silty-clay-loam,which are distinctive in texture and organic carbon(OC).In the soil zone(uredδ18O-NO3-suggested the ubiquitous of nitrification regardless of soil *** the subsoil zone(>1 m in depth),however,the concurrent enrichment ofδ15N-NO3-andδ18O-NO3-indicated the occurrence of denitrification,which showed a dependence on subsoil ***,during wheat and maize land uses,denitrification removed as much as 76%-88%of the total nitrate where the subsoil was dominated by stratified OC-rich *** contrast,only 0%-28%of the nitrate was degraded via denitrification where the subsoil was composed of uniform,OC-depleted ***,inactive denitrification and higher permeability in the silty-loam VZ implied higher groundwater *** observation was consistent with the fact that groundwater NO3--N concentration beneath silty-loam(11.24 mg l-1)was over two times higher than that of the silty-clay-loam(5.32 mg l-1),where stricter fertilization management and conservation strategies should be applied to protect groundwater quality.

关键词： Vadose zone Silty-loam Silty-clay-loam Nitrogen transformation Groundwater vulnerability Stable isotopes

Acute toxicity assessment of drinking water source with luminescent bacteria: Impact of environmental conditions and a case study in luoma lake, East China

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 201-209页

作者： Xuewen Yi Zhanqi Gao lanhua l.u Qian Zhu Guanjiu Hu xiaohong Zhou College of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China State Environmental Protection Key laboratory of Monitoring and Analysis for Organic Pol.utants in Surface Water Jiangsu Environmental Monitoring CenterNanjing 210036China State Key Joint laboratory of ESPC School of EnvironmentTsinghua UniversityBeijing 100084China

Protecting the quality of lake watersheds by preventing and reducing their contamination is an effective approach to ensure the sustainability of the drinking water *** this study,acute toxicity assessment was conducted on the basis of acute bioluminescence inhibition assay using the marine bacterium Vibrio fischeri as the test organism and luoma lake drinking water source in East China as the research *** suitable ranges of environmental factors,including pH value,organic matter,turbidity,hardness,and dissolved oxygen of water samples were evaluated for the toxicity testing of bioluminescent *** physicochemical characteristics of water samples at the selected 43 sites of luoma lake watershed were *** showed that the variations in pH value(7.31-8.41),hardness(5-20°d)and dissolved oxygen(4.44-11.03 mg/l)of luoma lake and its main inflow and outflow rivers had negligible impacts on the acute toxicity testing of *** luminescence inhibition rates ranged from-11.21%to 10.80%at the 43 ***'s correlation analysis in the experiment revealed that temperature,pH value,hardness,and turbidity had no correlation with luminescence inhibition rate,whereas dissolved oxygen showed a weak statistically positive correlation with a Pearson correlation coefficient of 0.455(p<0.05).

关键词： Bioluminescent bacteria Acute toxicity Pearson correlation analysis Drinking water source Vibrio fischeri