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Identification of secondary organic aerosols based on aerosol mass spectrometry

中国科学：化学英文版 2010年第12期53卷 2593-2599页

作者： HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat environmental Science and Technology School of Environment and energy,Peking University Shenzhen Graduate School,Shenzhen 518055,China 2 State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental Sciences and Engineering,Peking University,Beijing 100871,China 3 Division of Environment,Hong Kong University of Science & Technology,Hong Kong,China Key Laboratory for Urban Habitat environmental Science and Technology School of Environment and energy Peking University Shenzhen Graduate School Shenzhen China State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental Sciences and Engineering Peking University Beijing China Division of Environment Hong Kong University of Science & Technology Hong Kong China

Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so *** to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol *** study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) *** sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer *** showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic *** with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary *** ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the *** most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this *** study provides a new technical method and a new idea for SOA investigation.

关键词： secondary organic aerosol aerosol mass spectrometry positive matrix factorization (PMF)

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Bridge pier failure probabilities under combined hazard effects of scour, truck and earthquake. Part Ⅰ: occurrence probabilities

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 229-240页

作者： Zach Liang George C. Lee department of Mechanical and Aerospace Engineering Unidersity at Buffalo Depart of Civil Structural and Environmental EngineeringUniversity at Buffalo

In many regions of the world, a bridge will experience multiple extreme hazards during its expected service life. The current American Association of State Highway and Transportation Officials （AASHTO） load and resistance factor design （LRFD） specifications are formulated based on failure probabilities, which are fully calibrated for dead load and nonextreme live loads. Design against earthquake loads is established separately. Design against scour effect is also formulated separately by using the concept of capacity reduction （or increased scour depth）. Furthermore, scour effect cannot be linked directly to an LRFD limit state equation, because the latter is formulated using force-based analysis. This paper （in two parts） presents a probability-based procedure to estimate the combined hazard effects on bridges due to truck, earthquake and scour, by treating the effect of scour as an equivalent load effect so that it can be included in reliability-based bridge failure calculations. In Part I of this series, the general principle of treating the scour depth as an equivalent load effect is presented. The individual and combined partial failure probabilities due to truck, earthquake and scour effects are described. To explain the method of including non-force-based natural hazards effects, two types of common scour failures are considered. In Part 11, the corresponding bridge failure probability, the occurrence of scour as well as simultaneously having both truck load and equivalent scour load are quantitatively discussed.

关键词： multi-hazards load and resistance factor design bridge scour

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Entrepreneurship training:its influences on innovation potentials among nursing students

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Frontiers of Nursing 2024年第1期11卷 85-98页

作者： Asmaa Abdel Rahman Abdel Rahman Dalia Abdallah Abdelatief Medical Surgical Nursing department Faculty of NursingAin Shams UniversityCairoEgypt

Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing ***:A quasi-experimental design was utilized to conduct this *** study was conducted in the classroom at the faculty of nursing,and the“i Hub”center at Ain Shams University(ASU)in Cairo,Egypt.A purposive sample of 42 nursing students who participated in the“Ain Shams University-innovate”competition from the Faculty of Nursing of ASU were included in this *** collection tools included(1)Nursing students'innovation skills assessment questionnaire and(2)Innovative projects evaluation ***:There was a statistically significant difference between the mean scores of nursing students'total innovation skills pre-and post-implementation of entrepreneurship training,where P-value<***:The results of the current study support the research hypothesis because the implementation of entrepreneurship training positively affects nursing students'innovation *** entrepreneurship education in nursing and integrating it into nursing programs will stimulate creativity,innovation,and entrepreneurship among nursing students and health care services.

关键词： entrepreneurship training innovation potentials nursing students creative skills energy/motivation

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Silver recovery as Ag^0 nanoparticles from ion-exchange regenerant solution using electrolysis

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Journal of environmental Sciences 2019年第4期31卷 161-173页

作者： Tabish Nawaz Sukalyan Sengupta Chen-Lu Yang Civil and environmental Engineering department University of Massachusetts Dartmouth Center for Innovation and Entrepreneurship University of Massachusetts Dartmouth

Many silver(Ag)containing consumer-products(***)release Ag into the environment,posing ecotoxicological *** recovery mitigates environmental hazards,recycles Ag,and leads to *** the present work,Ag has been recovered as Ag^0nanoparticles from the spent solution(thiourea(TU)～0.5 mol/L pH～1.1–1.2,and Ag～550 mg/L)obtained from the regeneration of an Ag-loaded resin using a simple undivided electrolytic *** reclaimed regenerant solution has been recycled and reused in a closed-loop scheme over multiple *** process parameters,i.e.,current(0.05 A)and stirring speed(600 r/min),have been optimized for Ag recovery of～94%and TU loss of～2%.The reclaimed regenerant solution has been shown to regenerate Ag-loaded resin samples with>90%regeneration efficiency over 4 cycles of consecutive extraction and *** recovered Ag^0nanoparticles are monodisperse,consistently spherical in shape,and have a mean diameter of～6 nm with standard deviation of the Gaussian fit as～2.66 nm.

关键词： Silver recovery Ag^0 nanoparticles Waste management Thiourea Sustainability Resource recovery Electrowinning

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Disbond detection with piezoelectric wafer active sensors in RC structures strengthened with FRP composite overlays

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 213-223页

作者： Victor Giurgiutiu Kent Harries Michael Petrou Joel Bost Josh B.Quattlebaum department of Mechanical Engineering University of South CarolinaUSA Associate Professor department of Civil and environmental Engineering University of South CarolinaUSA Assistant Professor department of Civil and environmental Engineering University of South CarolinaUSA Associate Professor department of Mechanical Engineering University of South CarolinaUSA Undergraduate Research Assistant department of Civil and environmental Engineering University of South CarolinaUSA Graduate Research Assistant

The capability of embedded piezoelectric wafer active sensors(PWAS)to perform in-situ nondestructive evaluation(NDE)for structural health monitoring(SHM)of reinforced concrete(RC)structures strengthened with fiber reinforced polymer(FRP)composite overlays is ***,the disbond detection method were developed on coupon specimens consisting of concrete blocks covered with an FRP composite *** was found that the presence of a disbond crack drastically changes the electromecfianical(E/M)impedance spectrum lneasurcd at the PWAS *** spectral changes depend on the distance between the PWAS and the crack ***,large scale experiments were conducted on a RC beam strengthened with carbon fiber reinforced polymer(CFRP)composite *** beam was subject to an accelerated fatigue load regime in a three-point bending configuration up to a total of 807,415 *** these fatigue tests,the CFRP overlay experienced disbonding beginning at about 500,000 *** PWAS were able to detect the disbonding before it could be reliably seen by visual *** correlation between the PWAS readings and the position and extent of disbond damage was *** preliminary results demonstrate the potential of PWAS technology for SHM of RC structures strengthened with FRP composite overlays.

关键词： FRP composite overlays composite strengthening and rehabilitation structural health monitoring piezoelectric wafer active sensors E/M impedance aging infrastructure disbond damage PWAS

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长壁放顶煤工作面沿空巷道的变形破坏机理

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Journal of Central South University 2024年第5期31卷 1542-1559页

作者：王浩森何满潮王炯王瑞明灿朱道勇马资敏 State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining&TechnologyBeijing 100083China NBK Institute of Mining Engineering University of British ColumbiaVancouver BC V6T 1Z4Canada Mining Engineering and Geology College Xinjiang Institute of EngineeringUrumqi 830023China department of Earth Sciences University of FlorenceFirenze 50121Italy College of Water&Architectural Engineering Shihezi UniversityShihezi 832003China School of Resource and environmental Engineering Shandong University of TechnologyZibo 255000China

本文利用物理和数值模型研究了长壁放顶煤工作面沿空巷道的变形和破坏机理。物理模型实验表明,长壁放顶煤工作面沿空巷道的变形破坏过程可分为四个阶段:初始变形阶段Ⅰ(相邻工作面后方-47~45 m)、快速变形阶段Ⅱ(45~150 m)、变形稳定阶... 详细信息

本文利用物理和数值模型研究了长壁放顶煤工作面沿空巷道的变形和破坏机理。物理模型实验表明,长壁放顶煤工作面沿空巷道的变形破坏过程可分为四个阶段:初始变形阶段Ⅰ(相邻工作面后方-47~45 m)、快速变形阶段Ⅱ(45~150 m)、变形稳定阶段Ⅲ(150~240 m)和压实稳定阶段IV(工作面后方240 m外)。值得注意的是,长壁放顶煤工作面沿空巷道围岩的大变形主要发生在快速变形阶段Ⅱ和变形稳定阶段Ⅲ。这主要是由沿空巷道上方的侧向悬臂梁结构旋转下沉过程中产生的应力集中造成的。因此,本文提出了一种创新方法,使用顶板预裂技术来优化巷道顶板结构,控制长壁放顶煤工作面沿空巷道围岩的大变形并自动留巷。数值模拟和现场应用表明,使用顶板预裂自动留巷技术后,长壁放顶煤工作面沿空巷道实体煤帮的支承压力、顶底板变形量和两帮变形量分别降低了6.49%、79.25%和60%。因此,顶板预裂自动留巷技术可以有效控制长壁放顶煤工作面沿空巷道的围岩大变形。本文所提出的长壁放顶煤工作面顶板预裂自动留巷技术可以为厚及特厚煤层综放工作面使用切顶卸压无煤柱自成巷技术提供参考。

关键词：物理模型实验变形机理沿空巷道顶板预裂

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Characteristics of greenhouse gas emissions from rice paddy fields in South Korea under climate change scenario RCP-8.5 using the DNDC model

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Pedosphere 2021年第2期31卷 332-341页

作者： Wonjae HWANG Chanyang KIM Kijong CHO Seunghun HYUN department of environmental Science and Ecological Engineering Korea UniversitySeoul 02841(South Korea)

Understanding the greenhouse gas(GHG)emission from rice paddy fields is essential to come up with appropriate countermeasure in response to global ***,GHG emissions from paddy fields in South Korea are not well *** objectives of this study were to estimate the carbon dioxide(CO_(2))and methane(CH_(4))emissions from rice paddy fields in South Korea,under the Representative Concentration Pathway 8.5(RCP-8.5)climate change scenario using the DNDC(i.e.,DeNitrification-DeComposition)model at 1-km^(2)*** performance of the model was verified with field data collected using a closed chamber,which supports the application of the model to South *** the model predictions and field measurements showed that most(>95%)GHG emissions occur in the cropping period,between April and *** a baseline(assuming no climate change),the national sums of the CO_(2)and CH_(4)emissions for the 2020 s and 2090 s were estimated to be 5.8×10^(6)and 6.0×10^(6)t CO_(2)-equivalents(CO_(2)-eq)year^(-1)for CO_(2)and 6.4×10^(6)and 6.6×10^(6)t CO_(2)-eq year^(-1)for CH_(4),respectively,indicating no significant changes over 80 *** RCP-8.5,in the 2090 s,CH_(4)emissions were predicted to increase by 10.7×10^(6)and 14.9×10^(6)t CO_(2)-eq year^(-1),for a 10-or 30-cm tillage depth,***,the CO_(2)emissions gradually decreased with rising temperatures,due to reduced root *** tillage increased the emissions of both GHGs,with a more pronounced effect for CH_(4)than CO_(2).Intermittent drainage in the middle of the cropping season can attenuate the CH_(4)emissions from paddy *** findings of this work will aid in developing nationwide policies on agricultural land management in the face of climate change.

关键词： CH_(4) CO_(2) model performance paddy soil rising temperature tillage depth

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Wheat-Exuded Organic Acids Influence Zinc Release from Calcareous Soils

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Pedosphere 2011年第5期21卷 657-665页

作者： M.A.MAQSOOD S.HUSSAIN T.AZIZ M.ASHRAF Institute of Soil and environmental Sciences University of Agriculture department of Soil Science University of Sargodha

Rhizosphere drives plant uptake of sparingly soluble soil zinc(Zn).An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes(Sehar-06 and Vatan),Zn fractions in 10 different calcareous soils from Punjab,Pakistan,and release of different soil Zn fractions by organic *** two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient *** a deficient Zn level,Sehar-06 released more maleic acid in the rhizosphere than *** soils used in the present study had very different physicochemical properties;their total Zn and Zn distribution among different fractions varied *** release behaviour was determined by extracting the soils with 0.005 mol L-1 citric acid or maleic *** parabolic diffusion model best described Zn release as a function of *** diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different *** Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg-1 using maleic acid and from 0.37 to 11.84 mg kg-1 using citric *** the selected calcareous soils,the results of stepwise linear regression indicated significant release of Fe-Mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-effcient ***,release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.

关键词： citric acid maleic acid phytoavailability plant uptake rhizosphere

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Responses of Ryegrass(Lolium perenne L.) Grown in Mudflats to Sewage Sludge Amendment

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Journal of Integrative Agriculture 2014年第2期13卷 426-433页

作者： BAI Yan-chao GU Chuan-hui TAO Tian-yun ZHU Xiao-wen XU Yi-ran SHAN Yu-hua FENG Ke College of environmental Science and Engineering Yangzhou University department of Geology Appalachian State University

Sewage sludge amendment （SSA） is an alternative waste disposal technique and a potential way to increase fertility of mudflats for crop growth. The present study aimed to assess the suitability of SSA by assessing the nitrogen （N） and phosphorous （P） uptakes, heavy metal accumulation, growth, biomass, and yield response of ryegrass （Lolium perenne L.） at 0, 30, 75, 150, and 300 t ha-1 SSA rates at various growth stages. The results showed that the highest biomass ofryegrass at seedling and vegetative stages were at 300 and 150 t ha-1 SSA rate, respectively. The increments of ryegrass yield at reproductive stage at 30, 75, 150, and 300 t ha1 SSA rates were 98.0, 122.6, 88.1, and 61.2%, compared to unamended soil. N and P concentrations in ryegrass increased with increasing SSA rates at all stages except N and P in roots dropped significantly at 300 t ha-1 rate at vegetative stage. The metal concentration for Mn, Cu, Zn, Ni, Cd, Cr, and Pb in shoot of ryegrass at 300 t ha-1 S SA rate increased by 0.63-, 2.34-, 15.02-, 0.97-, 10.00-, 0.01- and 1.13-fold, respectively, compared to unamended soil. However, heavy metal concentrations in shoot of ryegrass were lower than the standard for forage products in China. The study suggested that sewage sludge amendment in mudflat soils might be feasible. However, the impacts of sludge application on edible crop plants and soil environment need further investigations.

关键词： sewage sludge mudflat soil ryegrass growth metals

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Hybrid q-Rung Orthopair Fuzzy Sets Based CoCoSo Model for Floating Offshore Wind Farm Site Selection in Norway

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CSEE Journal of Power and energy Systems 2022年第5期8卷 1261-1280页

作者： Muhammet Deveci Dragan Pamucar Umit Cali Emre Kantar Konstanze Kolle John O.Tande department of Industrial Engineering Turkish Naval AcademyNational Defence UniversityIstanbul 34940Turkey department of Operations Research and Statistics Faculty of Organizational SciencesUniversity of BelgradeBelgradeSerbia department of Electric Power Engineering Norwegian University of Science and TechnologyTrondheim NO-7491Norway department of Electric Power Technology SINTEF Energy ResearchTrondheim NO-7491Norway department of energy Systems SINTEF Energy ResearchTrondheim NO-7034Norway

Unlocking offshore wind farms’high energy generation potential requires a comprehensive multi-disciplinary analysis that consists of intensive technical,economic,logistical,and environmental *** wind energy projects have high investment volumes that make it essential to conduct extensive site selection to ensure feasible investment decisions that reduce the potential financial *** on the scenario and circumstances,a ranking of alternative offshore wind energy projects helps to prioritise the investment *** algorithms based on expert knowledge can support the prioritisation and thus alleviate the work load for investment decisions in the *** case study considered here is to find the best site for a floating offshore wind farm in Norway from four pre-selected alternatives:Utsira Nord,Stadthavet,Froyabanken,and Trana *** propose a hybrid decisionmaking model as a combined compromised solution(CoCoSo)based on the q-rung orthopair fuzzy sets(q-ROFSs)including the weighted q-rung orthopair fuzzy Hamacher average(Wq-ROFHA)and the weighted q-rung orthopair fuzzy Hamacher geometric mean(Wq-ROFHGM)*** this model,the q-ROFSs based full consistency method(FUCOM)is introduced as a new methodology to determine the weights of the decision *** results of the proposed model show that the best site among the investigated four alternatives is A1:Utsira Nord.A sensitivity analysis has verified the stability of the proposed decision-making model.

关键词： Decision-making q-rung orthopair fuzzy sets Fuzzy hamacher site selection offshore wind farm FUCOM

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