Beijing haze type and agricultural biomass 北京霾 类型 及与生物质燃烧 秸秆焚烧的关系
Atmos.Chem.Phys.,10,8119–8130,2010 https://www.wendangku.net/doc/d510095393.html,/10/8119/2010/ doi:10.5194/acp-10-8119-2010
?Author(s)https://www.wendangku.net/doc/d510095393.html, Attribution3.0
License.Atmospheric Chemistry and Physics
Haze types in Beijing and the in?uence of agricultural biomass burning
W.J.Li1,2,3,L.Y.Shao2,and P.R.Buseck3
1Environment Research Institute,Shandong University,Jinan,Shandong250100,China
2State Key Laboratory of Coal Resources and Safe Mining&College of Geoscience and Surveying Engineering,China University of Mining and Technology,Beijing100083,China
3School of Earth and Space Exploration&Department of Chemistry and Biochemistry,Arizona State University,Tempe, AZ85287-1404,USA
Received:26January2010–Published in Atmos.Chem.Phys.Discuss.:22April2010
Revised:17August2010–Accepted:26August2010–Published:1September2010
Abstract.Emissions from agricultural biomass burning
(ABB)in northern China have a signi?cant impact on the re-
gional and global climate.The monthly average aerosol op-
tical depth(AOD)at550nm in northern China in2007had a
maximum of0.7in June.The AOD measurements are con-
sistent with regional brown hazes that occurred at that time,
which was a period of severe aerosol pollution.Aerosol par-
ticles were collected in urban Beijing from12to30June
2007,during a period of high haze,and studied using trans-
mission electron microscopy with energy-dispersive X-ray
spectrometry.The dominant particle types collected in the
?ne fraction(diameter<1μm)were ammonium sulfate,soot,
K2SO4,KNO3,and organic matter,except that the K salts
were minor between21and30June.K-rich particles as trac-
ers of biomass burning,together with wild?re maps,show
that intense regional ABB in northern China contributed sig-
ni?cantly to the regional haze between12and20June.We
therefore grouped the episodes into type-1and-2haze,with
the former occurring between12and20June and the latter
between21and30June.After long-range transport,ABB
particles in the type-1haze exhibited marked changes in mor-
phology,composition,and mixing state.KCl particles were
absent,presumably having been converted by heterogeneous
reactions to K2SO4and KNO3.Soot particles were mixed
with the other particle types.Abundant organic matter and
soluble salts emitted by ABB increased their sizes during
transport and resulted in more hygroscopic aerosol particles
in downwind areas,becoming additional cloud condensation
nuclei.The high AOD(average value2.2)in Beijing during
12to20June is partly explained by the hygroscopic
growth
Correspondence to:L.Y.Shao (shaol@https://www.wendangku.net/doc/d510095393.html,)of?ne aerosol particles and by the strong absorption of inter-nally mixed soot particles,both coming from regional ABB emissions.Therefore,it is important to consider the origins of the haze,which in turn leads to the different particle types. 1Introduction
Biomass burning is a global phenomenon that releases large quantities of gases and aerosol particles that affect the atmo-spheric chemistry and climate by scattering and absorbing solar radiation on regional and global scales(Crutzen and Andreae,1990).Aerosol particles from biomass burning also dramatically increase the concentration of cloud condensa-tion nuclei(CCN)and affect the formation and lifetime of clouds(Andreae et al.,2004;Roberts et al.,2003).Such aerosol particles serving as CCN also alter the radiation bud-get of clouds in the troposphere(IPCC,2007).In addition, because of the transport of biomass-burning particles with nutrient species(e.g.,S,K,and N)from agricultural regions into urban areas,these aerosols alter the regional biogeo-chemical cycling and adversely affect human health(Bow-man et al.,2009;Crutzen and Andreae,1990;Da Rocha et al.,2005;Koe et al.,2001;Niemi et al.,2005;Reid et al., 2005).
Agricultural biomass burning(ABB)in China is draw-ing worldwide attention because of its rapid development and increase in agricultural activities.Numerous studies have shown that the mixtures of pollutants from industries, biomass burning,and urban areas in northern China can be transported over the Paci?c Ocean(Jacob et al.,2003;Ma et al.,2003)into North America and thus cause problems across
Published by Copernicus Publications on behalf of the European Geosciences Union.
wide areas(de Gouw et al.,2004;Jaffe et al.,1999;Peltier et al.,2008;Yienger et al.,2000).
Compared with plumes from soil dust and industrial emis-sions,as well as with relatively clean air masses,those over northern China that contain emissions from ABB show dis-tinct optical properties(Yang et al.,2009).In particular,mas-sive quantities of?ne soot particles(also known as black car-bon or elemental carbon)are emitted into the troposphere. According to Ramanathan and Carmichael(2008),soot in the troposphere is the second greatest contributor to global warming after CO2.
In the atmosphere,soot particles commonly acquire coat-ings of sulfates,organic matter,and sulfuric acid(Adachi and Buseck,2008;Adachi et al.,2010;Johnson et al.,2005; P′o sfai et al.,1999),thereby enhancing the light absorption of soot(Chung and Seinfeld,2002;Jacobson,2001;Lesins et al.,2002;Zhang et al.,2008).For example,particles coated with sulfate absorb30%more light than soot alone(Fuller et al.,1999).Clearly,a complete physical and chemical inves-tigation of ambient ABB aerosol particles,most particularly soot particles,must be conducted before the climate impacts of aerosols can be evaluated for China.
In recent studies of ABB from China,Cao et al.(2008) estimated that emissions from straw burning amount to 140Tg/year.Duan et al.(2004)found that monthly aver-age concentrations of K in Beijing were three times higher in June than in May,likely because of ABB emissions.Zhang et al.(2007)showed that such emissions increased both organic and elemental carbon concentrations and that smoldering and ?aming signi?cantly in?uenced the formation of elemental carbon and polycyclic aromatic hydrocarbons(PAHs).
In spite of the above studies,information is lacking about the composition and mixing states of aged ABB aerosol par-ticles in urban regions and their impacts on regional climate. Two reasons explain this situation.First,ABB emissions oc-cur at different times within the spring season because timing of farming activities change with latitude throughout China. Therefore,?exible sampling schedules are needed.Second, the frequent episodes of severe pollution with high mass con-centrations of particulate matter(PM)from industrial and vehicular emission in urban areas may mask ABB aerosols, suggesting that bulk analytical methods cannot adequately identify such particles.Also,bulk methods,which focus on the composition of aerosol particle obtained from relatively long sampling periods,are unable to identify ABB particles during those episodes.In addition,bulk methods only pro-vide information about aerosol mixtures,not individual ABB particles.
In contrast,individual-particle analysis using transmission electron microscopy(TEM)provides detailed information on individual particles at a high resolution(Buseck and P′o sfai, 1999;P′o sfai and Buseck,2010;Johnson et al.,2005).TEM is uniquely suited for observing and analyzing the morphol-ogy,size,structure,and mixing state of such aerosol parti-cles(Johnson et al.,2005;P′o sfai et al.,1999;Li and Shao, 2009b).
The goal of this paper is to determine the properties of in-dividual ABB particles that are signi?cant contributors to the regional brown hazes in northern China and that are promi-nent in Beijing.K-rich aerosol particles serve as tracers of biomass burning and,together with wild?re maps,were used to identify regional ABB sources for the https://www.wendangku.net/doc/d510095393.html,-ing TEM,particular attention was paid to the phase and mixing state of individual aerosol particles.Air-mass back-trajectories,satellite observations of?res,and aerosol optical depth(AOD)measurements from sun photometers were used to evaluate the effects of ABB-related aerosol particles in the brown hazes.
2Materials and methods
2.1Aerosol sampling and laboratory preparations Aerosol particles were collected during seven haze episodes between12and27June2007in northwestern urban Beijing (39?59?N,116?20?E)(Table1).Samplers were mounted 18m above ground on the roof of a building on the cam-pus of the China University of Mining and Technology.Par-ticles were collected onto copper TEM grids coated with carbon?lm(carbon type-B,300-mesh copper,Tianld Co., China)using a single-stage cascade impactor with a0.5-mm-diameter jet nozzle with a?ow rate of1.0L min?1.Sam-pling times varied from30to120s,depending on the visibil-ity and thus likely particle loading.Measurements of wind speed,wind direction,relative humidity,barometric pressure, and ambient temperature were automatically recorded by a Kestral4000Pocket Weather Tracker(Nielsen-Kellermann Inc.,USA)(Table1).After collection,each sample was placed in a sealed dry plastic tube and stored in a desiccator at25?C and20±3%RH to minimize exposure to ambient air and preserve it for analysis.
Additionally,K2SO4and KNO3aerosol particles were generated from1M solutions prepared from analytical reagent-grade chemicals(97%purity,Aldrich).The parti-cles were dried using a silicon diffusion drier(TSI Model 3062)to an RH of20%(TSI,2003).Single particles were de-posited by diffusion onto TEM grids,a technique described by Freney et al.(2009).
2.2TEM analysis
Aerosol particles were analyzed with a Philips CM200TEM operated at200kV.The distribution of aerosol particles on the TEM grids was not uniform.Coarser particles were de-posited near the center of the grids and?ner particles on the periphery.Therefore,to ensure that the analyzed particles were representative of the entire size range,three to four ar-eas were chosen from the center and periphery of the sam-pling spot on each grid.An ellipse was used to?t a particle
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https://www.wendangku.net/doc/d510095393.html,rmation on analyzed samples from urban Beijing.
Date Start Time T RH a P WS WD V
UTC?C mean,%max,%hPa(m s?1)km 12/06/200709:3020626710002SE3
17/06/200709:453042489993SSE4
19/06/200702:3031445110042WSS3
19/06/200705:3032505310021SSE0.5
20/06/200707:0028666910013S2
21/06/200703:003636399992WS3
23/06/200704:002862659932SE3
23/06/200704:102862659932SE3
27/06/200702:003264679913SEE2
27/06/200702:103264679913SEE2
27/06/200705:452470759918WSS4
T–temperature,RH–relative humidity,P–barometric pressure,WS–wind speed,WD–wind direction,V–visibility.
a RH includes mean and maximum value during each sampling period.
outline,and the arithmetic mean of the short and long axes of the ellipse was used to determine the particle diameter (P′o sfai et al.,2003).
Elemental compositions were determined semi-quantitatively by using an energy-dispersive X-ray spectrometer(EDS)that can detect elements heavier than C.For some particles,EDS data were combined with selected-area electron diffraction(SAED)to verify their identities.Copper was not considered because of interfer-ences from the copper TEM grid.To understand the details of internally mixed aerosol particles and their sources,the compositions of different parts of targeted aerosol particles were analyzed(e.g.,coatings,inclusions,and aggregations). EDS spectra were collected for30s in order to minimize radiation exposure and potential beam damage.Prior TEM observations of the major aerosol types collected in brown hazes from30May to10June2007revealed mineral,soot, organic matter,K-rich,S-rich,?y ash,and metal particles (Li and Shao,2009a).In the current study,we focused on the soot,organic matter,K-rich,and S-rich particles.
3Results
3.1Regional haze in northern China
The regional distribution of aerosols and AOD were obtained from Giovanni maps[Giovanni is an acronym for the G ES-DISC(Goddard Earth Sciences Data and Information Ser-vices Center)I nteractive O nline V isualization AN d a N alysis I nfrastructure]from MODIS(Moderate Resolution Imag-ing Spectroradiometer)satellite data(Acker and Leptoukh, 2007).These data indicate that severe aerosol pollution oc-curred in northern China(Fig.1a),with a maximum monthly average AOD at550nm of0.7in June2007(Fig.1b).Such
a 2
3
Fig.1.Aerosol optical depth(AOD)map and monthly average AOD of area-averaged time series over northern China(region: 101.25E–121.99E,26.02N–44.30N)derived from MODIS-Terra data from January to December2007(https://www.wendangku.net/doc/d510095393.html,/ giovanni/).(a)Mean AOD value at550nm from January to Decem-ber2007.(b)Monthly mean AOD value in2007.
high value indicates high PM loading in the troposphere and is related to severe pollution episodes such as regional brown hazes or dust storms(Du et al.,2008;Eck et al.,1999).
Asian dust storms usually begin in late February and end in mid-May(Shao et al.,2008;Zhang et al.,2003).There-fore,the regional pollution episodes in June are more likely to be the brown hazes,consistent with our observations at the sampling site.The aerosols in the regional hazes were largely contributed by anthropogenic sources such as indus-trial emissions,vehicular fossil fuel combustion,and ABB (Li and Shao,2009a).The hazy days had visibility less than 5km,wind speeds less than3m s?1,and winds from south of Beijing(Table1).The regional hazes disappeared in half a day or less because of the onset of abrupt cold fronts from the west,and then formed again within a day or less dur-ing the sampling period.The daily mass concentrations of PM10and SO2in June displayed dramatic changes(Fig.2), consistent with the visual observations of the haze.The
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2
3 Fig.2.Daily mass concentrations of PM
10,SO2,and NO2in Bei-jing in June2007(https://www.wendangku.net/doc/d510095393.html,/).Sample collection was conducted during the?ve haze episodes(HE-1,HE-2,HE-3, HE-4,and HE-5)indicated by the orange vertical bars.Widths of the bars indicate the haze periods.
frequent alternation between clear and hazy days is conspic-uously noticeable in what Jia et al.(2008)called a sawtooth cycle.Eleven samples collected in the?ve haze episodes (HE-1,HE-2,HE-3,HE-4,and HE-5)were selected for de-tailed analysis(Fig.2).
Mass concentrations of PM10,SO2,and NO2on hazy days ranged from192to286μg m?3,16to48μg m?3,and50to 83μg m?3,respectively(data provided by the Beijing Meteo-rological Bureau).Pollutants on hazy days(peaks in the saw-tooth cycle)showed mass concentrations2to3times higher than pollutants on clear days(valleys in the sawtooth cycle), suggesting that the stable meteorological conditions on hazy days favored the accumulation of air pollutants that were then slowly transported into adjacent areas.
3.2Major?ne aerosol particles and their size
distributions
In this section,we describe the different kinds of particles in the brown hazes.We then combine these results with the MODIS data to identify those speci?cally related to ABB in section3.3.The experimental data are based on TEM analysis of individual aerosol particles from the brown haze episodes.We distinguished seven kinds of aerosol particles: mineral,soot,organic matter,?y ash,and K-rich,S-rich, and metal particles(Li and Shao,2009a).Sizes of the1066 analyzed haze particles collected between12and27June range from0.01to13μm,with a median diameter of1.4μm (Fig.3).Sizes of the470K-and S-rich particles range from
0.01to10μm,with a median diameter of0.7μm.
K-rich particles,one of the abundant inorganic aerosol constituents of the brown hazes,are regarded as tracers of biomass burning and biofuel emissions(Reid et al.,2005;
Adachi and Buseck,2008;Engling et al.,2009).Most K-rich
Fig. 3
2
3
Fig.3.Size distributions of1066haze particles(i.e.,mineral,soot, organic matter,K-rich,S-rich,?y ash,and metal particles)and 470K-and S-rich particles.The size distributions represent the fraction sampled rather than the total collection of aerosol parti-cles.Most K-and S-rich particles were internally mixed with soot, organic matter,or both.
particles are irregularly shaped.EDS measurements show that they consist mostly of N,Na,O,S,and K and are free of Cl(Fig.4).Diffraction patterns indicate the presence of K2SO4and KNO3,and they are internally mixed(Fig.4). The KNO3is more beam-sensitive than the K2SO4,making good diffraction patterns of KNO3dif?cult to obtain.These EDS and SAED results are consistent with our observations of laboratory-generated K2SO4and KNO3particles.KCl is barely detected in the samples,even though it has been found to be internally mixed with K2SO4and KNO3in fresh biomass burning plumes(Li et al.,2003;Adachi and Buseck, 2008).
S-rich particles,another of the abundant inorganic aerosol constituents of brown hazes,appear as subrounded masses on TEM grids,with their principal elements being N,O,S, and minor Na and K(Fig.5).Their SAED patterns indi-cate most are ammonium sulfate((NH4)2SO4).In addition, sulfate particles with one or more rings of smaller particles (Fig.5)suggest that they are somewhat more acidic than pure ammonium sulfate(Buseck and P′o sfai,1999;Sheridan et al., 1993).The abundant(NH4)2SO4particles in Beijing air have been reported to form through chemical reactions between NH3and H2SO4(Yao et al.,2003).
Soot particles are abundant in urban air and commonly oc-cur as inclusions in or associated with K-and S-rich parti-cles(Johnson et al.,2005;Adachi and Buseck,2008;Li and Shao,2009a;Adachi et al.2010).The soot particles display their characteristic morphologies of chains and agglomerates (Fig.6a).High-magni?cation TEM images show that some aggregates contain as few as ten to as many as hundreds of carbon spheres,with diameters from10to50nm and with
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Fig. 4
2 3
Fig.4.Mixtures of (a)KNO 3and (b)K 2SO 4from samples collected on 17June (left)and 19June (right),respectively,based on their compositions and crystal structures from EDS and SAED measurements.The inset shows an indexed diffraction pattern of K 2SO 4.KNO 3is more beam-sensitive than K 2SO 4.
some as large as 100nm.As is typical,the soot spheres dis-play the onion-like structures of disordered graphitic layers (Fig.6b).
Although volatile and some semi-volatile chemical species evaporate in the high vacuum of electron microscopes,individual-particle analysis using electron microscopy has been used to study non-volatile particles,including or-ganic matter and its mixing characteristics in the atmosphere (P′o sfai et al.,2003;Niemi et al.,2005;Adachi and Buseck,2008;Li and Shao,2010).Much of the organic matter contains C and minor N,O,S,and K and lacks graphitic,soot-like structures in high-resolution TEM images (Fig.6).It typically displays rounded,relatively non-descript shapes and commonly coats or embeds other particle types such as the K-rich,S-rich,and soot particles.3.3
Identi?cation of the regional hazes affected by agricultural biomass burning
ABB and its associated impacts on Beijing air were reported by Li et al.(2008)and Duan et al.(2004),who showed that the intense ABB in some provinces (e.g.,Shandong,Hebei,Henan,Anhui)of northern China is usually concentrated in June.MODIS wild?re maps show that intense ABB occurred in northern China between 10and 20June 2007,and that slight ABB occurred between 21and 30June (Fig.7).
Many K-rich particles and some S-rich particles occurred during the former period,whereas the opposite situation ex-isted during the second period.The abundance of K-rich par-ticles in the haze between 12and 20June probably arose from biomass burning,consistent with the results of Reid et al.(1998),P′o sfai et al.(2003),and Engling et al.(2009).Samples were collected during that period,and air masses during the HE-1,HE-2,and HE-3episodes were transported through the area with intense ABB.Air masses during HE-4and HE-5were transported through areas with slight ABB (Fig.7).Prevailing southerly or southeasterly winds (Ta-ble 1)likely carried large amounts of ?ne ABB particles over long distances into the regional haze of Beijing during the period 12to 20June.
Using wild?re maps and individual-particle analysis,we distinguished between what we call type-1and -2haze,with the former occurring between 12and 20June and the latter between 21and 30June.Figure 8a,which is based on 470
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Fig. 5
2
3
Fig.5.TEM image and element content(S,N,O,and K)of S-rich particle(23June).The diffraction pattern was obtained from a similar-looking particle,which was destroyed during electron-beam exposure.
K-and S-rich particles,shows that65%of aerosol particles in type-1haze fall to the left of the K2SO4line,while only 9%in type-2haze do.The particles to the left of the K2SO4 line are enriched in K and contain minor S.Based on the EDS measurements and SAED analysis,the major particles on the left are dominated by K2SO4,KNO3,or mixtures of both(Figs.4and7b).The low-magni?cation TEM images also show that there are more complex mixtures of the K-rich and S-rich particles(Fig.8b)from type-1haze than the S-rich particles(Fig.8c)from type-2haze.On the other hand,mean values of AOD and water vapor content(WVC)between12 and20June were2.0and2.2,respectively(Fig.9).The mean values of AOD and WVC during the period21to28June were1.1and2.7,respectively(Fig.9).
4Discussion
4.1Effects of ABB emissions on the brown hazes Transported ABB emissions not only increased the atmo-spheric loading but also changed the chemical and physical properties of aerosol particles in downwind areas.Brown hazes over northern China are normally produced by emis-sions from industry,fossil fuels(e.g.,vehicles and cooking), and soil dust from natural and anthropogenic activities(Li and Shao,2009a).We assumed that these sources had a con-stant emission rate throughout the period of the study.Dur-ing the sampling period,daily average mass concentrations of PM10and SO2between12and20June and21and30 June decreased from192μg m?3to143μg m?3,and from 37μg m?3to18μg m?3,respectively(Fig.2).We infer from wild?re maps(Fig.7)that the intense ABB emissions in type-1haze increased the loading of PM10and SO2in Bei-jing air.
ABB can emit large quantities of?ne primary particles (e.g.,organic matter and K-rich particles),soot,and gases (e.g.,VOCs,CO,NO x,SO2,and NH3)into the troposphere (Crutzen and Andreae,1990).Reid et al.(1998)estimated that condensation and gas-to-particle conversions of vapors from biomass burning increased the aerosol mass by20to 40%.In addition,the mean WVC value is slightly higher in type-2haze than in type-1haze(Fig.9),consistent with the RH measurements in Fig.S1.However,type-1haze has a mean AOD double that of the type-2haze in this study (Fig.9).The most logical explanation is that the intense ABB emissions in the type-1haze increased the AOD. Internally mixed?ne particles are common in the hazes (Fig.8b).Soot and organic matter occur as inclusions in K-and S-rich particles(Fig.10),and only small quantities of externally mixed organic matter and soot particles were observed on the TEM grids that sampled the hazes.The re-sult is consistent with our investigation of aerosol particles in the brown hazes from31May to11June(Li and Shao, 2009a).The soot particles in Fig.10e–g became hydrophilic when they were coated with water-soluble compounds such as(NH4)2SO4,NH4HSO4,KNO3,K2SO4,or oxidized or-ganic matter,implying that soot can provide important nuclei for the development of?ne particles in the hazes. Abundant KCl particles have been detected in fresh smoke plumes of biomass burning,and they are transformed through heterogeneous chemical reactions to K2SO4and KNO3(Engling et al.,2009;Li et al.,2003;P′o sfai et al., 2003;Adachi and Buseck,2008).The dominance of K2SO4 and KNO3and absence of KCl in type-1haze suggests that KCl from ABB presumably reacted with nitric acid and sul-furic acid in the atmosphere,prior to sampling.In addition,
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Fig. 6
2 3
Fig.6.TEM images of soot aggregates and organic matter.(a)TEM image of chain-like soot aggregate from the haze on 27June.(b)High-magni?cation TEM image showing the onion-like structures and disordered graphitic layers typical of soot.(c)Mixture of organic matter,ammonium sulfate,and soot from the haze on 27June.
3 4
Fig.7.Maps of northern China and ?ve 48-h back trajectories (red lines)of air masses arriving at Beijing at a 500-m eleva-tion (https://www.wendangku.net/doc/d510095393.html,/HYSPLIT.php).(a)Areas of intense ABB during 10–20June.The orange dots represent the positions of wild?res.(b)More disperse and fewer ABB spots during 21–30June.
many S-rich particles in type-1haze contain minor K (Fig.5).A similar mixture was also observed in smoke hazes in Mex-ico (Yokelson et al.,2009).4.2
Further considerations about regional brown hazes over China
Field observations show that all brown hazes display sim-ilarities such as low visibility and a high load of PM,but aerosol particles in different hazes exhibit different composi-tions,morphologies,and mixing states.Furthermore,differ-ences in the chemical and physical properties of ?ne aerosol particles in different haze types (e.g.,dust,brown smoke,and non-smoke brown haze)also impact the regional and global climates differently (Wang et al.,2009).Therefore,we need to identify haze types as well as the properties of individual aerosol particles in different hazes.
Emissions from ABB produce high concentrations of gases and ?ne particles for brief periods each year.These gases and particles enhance coagulation and condensation onto pre-existing aerosol particles,resulting in signi?cant changes to their compositions,shapes,and mixing states (Bein et al.,2008).More importantly,however,high RH during brown hazes can promote the hygroscopic growth of K-rich,S-rich,and organic particles,or their mixtures.The positive correlation (R =0.9)between AOD and WVC dur-ing the type-1hazes (Fig.9)suggests that large amounts of aerosol particles can grow hygroscopically (Li et al.,2007).Whenever the RH is elevated,its importance to the AOD is substantially ampli?ed if the particles are hygroscopic (Bian et al.,2009).In addition,the AOD of aged soot in polluted air is increased over that of fresh soot and correlates strongly with RH (Zhang et al.,2008),leading to even greater de-creases in visibility.
Morning and night relative humidity in June normally reaches 80%or higher but then decreases to between 20and 60%from midday to late afternoon (Fig.S1).Therefore,when we consider the climate effects of aerosol particles in regional haze,the solid and aqueous states of the hygro-scopic particles should be evaluated at different humidities.The variation of humidity during a haze episode can create cyclic changes of the soluble particles between the aqueous and solid states.
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Fig. 8
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3
https://www.wendangku.net/doc/d510095393.html,parison of compositions and morphologies of individual ?ne particles from different haze episodes.(a)Separation of type-1and-2haze according to the S/K ratio of the respective aerosol particles.The open triangles represent the weight percentages of S and K in the measured particle.The solid line indicates the weight percentage of S and K from measurements of K2SO4particles gen-erated in the laboratory.All analyses were made using the same EDS instrument,yielding similar uncertainties,and are thus inter-nally consistent.(b)Example of aerosol particles from a type-1 haze(17June).(c)Example of aerosol particles from a type-2haze (23June).Fig. 9
2
3
Fig.9.Correlation between the AOD(“level2.0,quality assured”)
at440nm and water vapor content during type-1and-2haze.Data
points are from the NASA Aeronet network(http://aeronet.gsfc.
https://www.wendangku.net/doc/d510095393.html,/)and were obtained by sun photometers at15-min inter-
vals during the sampling period at the Beijing site,except that data
points were excluded when it was cloudy or raining.
The high AOD values over northern China suggest that the
haze particles reduce solar?ux on the ground and cool the
surface atmosphere.In contrast,the internally mixed soot
particles in regional hazes absorb solar radiation and heat the
upper atmosphere.Recent observations of radiative forcing
from aerosols in regional hazes over northern China show
that aerosol particles under hazy weather conditions generate
a positive heating effect on the atmospheric column(Wang et
al.,2009;Xia et al.,2006).Once aerosols alter the radiation
budgets of the lower and upper atmospheres,a haze episode
may persist because the atmosphere becomes more stable.
Furthermore,the change may affect the development and
microphysics of clouds by reducing vertical heat exchange
and restricting convective transport(Fan et al.,2008).Sig-
ni?cantly,these aged?ne aerosol particles(Fig.10)can be
transported great distances and have the ability to carry toxic
materials such as heavy metals and PAHs(Guilloteau et al.,
2009;Li and Shao,2009a).The adverse effects of these
aerosol particles on human health merit serious attention.
5Conclusions
The AOD from Giovanni map shows that the monthly av-
erage value of550nm in the region had its maximum(0.7)
in June2007.TEM/EDS measurements showed that potas-
sium salts(K2SO4and KNO3)were abundant in?ne par-
ticles collected during12–20June,and were minor during
21–30June.To highlight the contrast,we grouped the haze
episodes into two categories,with HE-1to HE-3(12–20
June)called“type-1haze”,and HE-4to HE-5(21–30June) Atmos.Chem.Phys.,10,8119–8130,https://www.wendangku.net/doc/d510095393.html,/10/8119/2010/
Fig. 10
2 Fig.10.Examples of mixtures of organic matter,K-rich and S-rich particles,and soot.(a)K 2SO 4(beam damaged)with organic coating (12June),(b)KNO 3with organic matter (12June),(c)S-rich particle with thick organic coating (19June),(d)(NH 4)2SO 4with organic matter (19June),(e)soot,organic matter,and K 2SO 4(19June),(f)soot embedded within (NH 4)2SO 4(20June),(g)soot with S-rich coating (20June).
called “type-2haze.”Consistent with MODIS wild?re maps and air mass back-trajectories,the abundant K-rich particles indicated that ABB contributed heavily to type-1haze,and signi?cantly in?uenced Beijing air quality.
The anthropogenic sources of aerosol particles contribut-ing to the regular haze days (i.e.,type-2haze)in Beijing mainly consist of industry (steel and power plants),trans-portation,waste incineration,and cooking (Li and Shao,2009a).However,the copious organic matter,soot parti-cles,and gases emitted by ABB enhance the formation of secondary particles and the coagulation of pre-existing inor-ganic particles,resulting in more complex aerosol particles for type-1haze than for type-2haze.
Soot particles from ABB were generally mixed with potas-sium and ammonium salts,and organic matter.The aging of soot particles may increase the absorption of visible so-lar radiation when compared to soot alone (Jacobson,2001;Adachi et al.,2010).In addition,abundant K 2SO 4and KNO 3in the absence of KCl illustrate that aerosol particles emit-ted by ABB reacted during their transport to the sampling site.Therefore,ABB emissions after atmospheric residence not only complicated the chemical transformation of aerosol particles during the transport but also changed their physical properties in downwind areas.Furthermore,the ABB con-tribution likely resulted in the doubling of the AOD due to type-1haze relative to that of type-2haze.Supplementary material related to this article is available online at:
https://www.wendangku.net/doc/d510095393.html,/10/8119/2010/acp-10-8119-2010-supplement.pdf .
Acknowledgements.We thank Wei Wang for assistance with sample collection and Evelyn Freney for providing two laboratory-generated samples of K 2SO 4and KNO 3.We appreciate Kouji Adachi’s comments,and acknowledge the use of the TEMs in
https://www.wendangku.net/doc/d510095393.html,/10/8119/2010/
Atmos.Chem.Phys.,10,8119–8130,2010
the LeRoy Eyring Center for Solid State Science at Arizona State University.Analyses and visualizations used in this study were produced with the Giovanni online data system,developed and maintained by the NASA Goddard Earth Sciences(GES) Data and Information Services Center(DISC).Financial support was provided by National Basic Research Program of China (2006CB403701),State Key Laboratory of Coal Resources and Safe Mining(SKLCRSM09KFB04),China Postdoctoral Science Foundation funded project(20090461213),and NSF grant ATM-0531926.
Edited by:D.Knopf
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酒精燃烧法测量土壤水分
酒精燃烧法测量土壤水分 土壤水分是土壤的重要组成部分，也是重要的土壤肥力因素。进行土壤水分的测定有两个目的：一是了解田间土壤的水分状况，为土壤耕作、播种、合理排灌等提供依据;二是在室内分析工作中，测定风干土的水分，把风干土重换算成烘干土重，可作为各项分析结果的计算基础。土壤水分的测量方法有很多种，有烘干法、酒精燃烧法、中子法、专业测量仪器法(如使用便携式土壤水分速测仪)，下面就来简单的了解一下酒精燃烧法的操作方法以及优缺点： 酒精燃烧法： 1.方法原理 本方法是利用酒精在土壤样品中燃烧释放出的热量，使土壤水分蒸发干燥，通过燃烧前后的质量之差，计算出土壤含水量的百分数。酒精燃烧在火焰熄灭前几秒钟，即火焰下降时，土温才迅速上升到180~200℃。然后温度很快降至85~90℃，再缓慢冷却。由于高温阶段时间短，样品中有机质及盐类损失很少。故此法测定土壤水分含量有一定的参考价值。 2. 操作步骤 称取土样5g左右(精确度0.01g)，放入已知质量的铝盒中。然后向铝盒中滴加酒精，直到浸没全部土面为止，并在桌面上将铝盒敲击几次，使土样均匀分布于铝盒中。将铝盒放在石棉铁丝网或木板上，点燃酒精，在即将燃烧完时用小刀或玻璃棒轻轻翻动土样，以助其燃烧。待火焰熄灭，样品冷却后，再滴加2ml酒精，进行第二次燃烧，
再冷却，称重。一般情况下，要经过3~4次燃烧后，土样才可以恒重。 3.结果计算同风干土样吸湿水的测定。 4.注意事项：本法不适用于含有机质高的土壤样品的测定，操作过程中注意防止土样损失，以免出现误差。 酒精燃烧法测定土壤水分快但精确度较低，只适合田间速测。土壤水分田间检测的话还可以使用土壤水分温度测量仪来进行操作，这种可以长期的进行检测土壤中的水分。
最新开工前看着前面一组完成的作品
电工顶岗实习总结 在这次为期40天的电工实习，我从感性上学到了很多东西，使我更深刻地了解到了实践的重要性，范文之心得体会:中级电工实习心得体会。只具有理论知识是不行的，更要有动手能力。通过实习我们更加体会到“学以致用”这句话中蕴涵的深刻道理。 本次实习的目的主要是使我们对电工工具、电器元件及线路安装有一定的感性和理性认识;了解一些线路原理以及通过线路图安装、调试、维修的方法;对电工技术等方面的专业知识做初步的理解;培养和锻炼我们的实际动手能力，使我们的理论知识与实践充分地结合，做到不仅具有专业知识，而且还具有较强的实际操作能力，能分析问题和解决问题的高素质人才。以前我们学的都是一些理论知识,比较注重理论性，而较少注重我们的动手锻炼，而这一次的实习有不少的东西要我们去想，同时有更多的是要我们去做，好多东西看起来十分简单，但没有亲自去做，就不会懂得理论与实践是有很大区别的，很多简单的东西在实际操作中就是有许多要注意的地方，也与我们的想象不一样，这次的实训就是要我们跨过这道实际和理论之间的鸿沟。理论说的再好，如果不付诸于实际，那一切都是空谈。只有应用与实际中，我们才能了解到两者之间的巨大差异。开始的时候，老师对电路进行介绍，我还以为电工实习非常简单，直至自己动手时才发现，看时容易作时难，人不能轻视任何事。连每一根电线，都得对机器，对工作，对人负责。这也培养了我们的责任感。这次实习很累，在安装过程中我们都遇到了不少困难，理论与实践是有很大区别的，许多事情需要自己去想，只有付出了，才会得到，有思考，就有收获，就意味着有提高，就增强了实践能力和思维能力。 通过这一个星期的电工技术实习，我得到了很大的收获，这些都是平时在课堂理论学习中无法学到的，我主要的收获有以下几点： 1.掌握了几种基本的电工工具的使用，导线与导线的连接方法，导线与接线柱的连接方法，了解了兆欧表的使用方法等基本常识; 2.了解了简单电工横杆的安装方法，掌握了一般开关的倒闸方法; 3.本次实习增强了我们的团队合作精神，培养了我们的动手实践能力和细心严谨的作风。 通过实践，深化了一些课本上的知识，获得了许多实践经验，另外也认识到了自己部分知识的缺乏和浅显，激励自己以后更好的学习，并把握好方向。信息时代，仅会操作鼠标是不够的，基本的动手能力是一切工作和创造的基础和必要条件。而且，现在严峻的就业形势让我认识到，只有不断增加自身能力，具有十分丰富的知识才能不会在将来的竞争中被淘汰。总而言之，这次实习锻炼了自己，为自己人生的道路上增添了不少新鲜的活力!我会一如既往，将自己的全部心血倾注于工作上。我们的工作需需要有积极的工作热情和踏实的工作作风。我将以
The Haze关于雾霾对话
(An Interview A reporter and a student from CSU) A：In recent years, we are facing a new environmental problems--the haze, which is not far away from us. The haze weather, everyone is a victim. Taday we are honored to interview a student from CSU whose research issue is about the haze. Hello, Miss B. Can you say something about the haze ? What is the haze? B：Ok, it;s my great honor for this interview. Haze is a disaster weather. The effective horizontal visibility is less than 10KM due to a large number of very small particles of dust, soot, salt evenly floating in the air, So the haze is an air mixed erosion phenomenon. A：What is the exactly reason of the haze? Or in other words, where are the small particles from? B：The source of the haze is complex. Motor vehicle exhaust in the city as well as other carbon source, especially in big cities, industrial production, construction, motor vehicle exhaust emissions of harmful material such as coal. A：In the past, we still use laege amount of coal, why the haze weather be so severe in recent years? B：In recent years, with the development of industry, motor vehicles increasing, emission of pollutants and a large number of suspended solids increased, which is difficult to spread timely, making our city looks gray. What’s worse, it brings great harm to human health. A：That’s it. Haze is a disaster weather, have great influence on the highway, railway, aviation, shipping, power supply system, the growth of crops. haze will cause decline in air quality, affecting the ecological environment, bring great harm to human health. What should we do to fight against this big enemy? B：It’s a huge project to control the haze. The country, the government, even all of us should do something. A：Can you explain in detail? B：OK. First, Increase the environmental law enforcement, must also make the rules, punish law enforcement personnel dereliction of duty. A：Experts tell that the haze problem must be solved from the source. What the government can do for this aspect? B：Close the severe pollution enterprises, eliminate backward technology and equipment,do less exhaust gas, promote the use of clean energy. A：Clean energy is important. Sush as natural gas, hydropower, wind power, nuclear power and solar power. B：Yeah, that’s it ! A：Now that the haze is seriously hamful to our body, how to protect ourselves from the harm? Can you give some suggestions? B：Avoid foggy morning to go outside, If you have to go out, it is best to wear a mask.Try to stay away from the road. A：The haze weather, everyone is a victim.To reduce the occurrence of haze weather is in need of "responsibility". What can we do to make our contributions? B：Improving stove combustion efficiency, reducing the solid fuel use, A variety of green plants, reducing the use private cars, more public transport. Life as much
乙醇燃烧热实验报告
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年度工作完成情况
工作业务完成情况 律回春晖渐，万象始更新。时光飞逝，2010年马上就要过去。我来公司也将有1年多的时间。将要对自己本职工作进行总结与计划。在工作一年当中，每个人现已有固定服务客户进行操作流程。身为公司的操作员，我们应该首先为公司利益着想，维护好与客户服务关系，同时要让客户对我们的服务表示满意。要经常与客户沟通，尽量客户对我们的一系列要求，双方可以互补协商。 来公司一年多时间，本人现主要负责（李尔长春汽车内饰件系统有限公司）GTI返协件市内运输业务，刚开始领导给予这项工作时，我一头雾水，总怕自己干的不好，对自己和工作都没有信心。接触这项工作时，只是简单跟着学习一下大概流程以及找相关人士办何手续，后来就是自己慢慢接触，刚开始看货物名称和一些人说的专业术语我不是很理解，不太懂，最后接触时间长了，不懂得就问问别人，慢慢干起来比较得心应手。回想起一年前工作的状态，我也有很多不足，有很多地方出现了问题，有时跟客户沟通比较少，不知道做事要有提前准备，导致客户对我公司的服务态度不是很满意。 （一）、客户信息与流程： 从刚开始接触这项工作时，我就没有提前和客户沟通好，不清楚Lear对我公司提货有什么样的要求？运输途中的发生的问题以及货物外包装情况。主要操作流程：1.如Lear需要货物应提前一天把备货单以邮件的方式发给大众计划员和取件负责人的邮箱。2.操作员需严格按照提货单提货，准备好车辆去国际物流取件并送往李尔。3.在
国际物流提货时，曾经也因为第一次接触，不清楚状况而出现提多件的情况，导致车辆不能出一汽大众门。经过一次教训现应该注意标识和条码零件号与数量是否相符，如有不符，则需和国际物流协商重新提货，并通知Lear计划员事件经过。提货时需要对提货的包装状态负责，如果包装箱有破损或是发现提货零件有质量问题，应立即通知Lear计划员确认是否继续提货。如果包装破损Lear急需次货物，则需在现场拍照，为客户提供依据。4.货物装车后要开出门证，出门证要对好每箱货物的数量，必须持有与装车的货物一致的物资出门证单才能开出大众。5.最近常有代购件，需要先去Lear拿代购协议，然后去大众财务部找人核价、审批、签字，一系列手续办好之后，方可提货。6.Lear卸货的同时，把物资出门证复印三份，各留一份，谁卸货谁做最后的签字，确保货物没有问题操作员留一份签收，作为以后对账结算的依据。 （二）、出现问题与解决方案： 现在返件比较多，生产量相对从前加大了很多，在返件过程中同样也出现了很多问题，例如：1.车辆运输方面，安排提货车辆经常紧张，返件常常因车辆排号和找件耽误时间。大众的装车人员只有一位，所以很局限，而且开出门证也需要一段时间，这样可能会影响其他地方用车的情况。导致现在只要用车就会很困难。况且国际物流现规定一些厂家需要下午提件，往往自家车辆到得很晚，有时国际物流工作人员就会和Lear计划员打电话进行投诉，这样会影响两家的合作关系。客户的要求我们也应尽量满足，公司本身的利益又不能受到影响，所
Excel的作品完成标准和要求
Excel的作品完成标准和要求 一、任务： 每个同学在规定的时间内，提交一个用excel2003设计完成的工作簿作品，作为该同学在高中信息技术课必修课学习阶段的主要学习效果的评价依据。 二、要求： 1、要求每个同学求独完成作品的设计制作工作。 2、要求作品所采用的基础数据有一定的真实性。注明数据出处。 3、要求作品能够对比较有实际意义的信息数据处理和管理。 4、要求作品有一定的使用价值和独创性。 5、作品适当采用如下技术手段：多张工作表、函数、排序、分类汇总、筛选、图表等。 三、完成方式： 1、作品的保存和提交：用个人姓名+班级命名，格式为xls.提交到教师机。 2、作品可提交到教师机或发送至邮箱zzfls18@https://www.wendangku.net/doc/d510095393.html,。 四、评价和使用： 1、作品评价标准：独立完成不抄袭、功能丰富不单调、有一定的实用性、有一定的独创性。 2、作品评分：作品评价分为A,B,C和D四个等级，对有特别突出的创意设计者，可评为A+。
五、设计项目参考 (下面题目任选一个完成)。 1、设计一个现场打分统计表： 要求：将评委给分填入表中后，立刻得出去掉一个最高分和一个最低分后的选手平均分和名次。并用一个直方图进行同步显示。 2、商品进销存账本 要求：对一批商品的进货、销售情况进行同步管理。 3、学习成绩统计分析 要求：对一次全年级的各个班级的各科考试成绩进行统计分析。4、邮包计费系统 要求：邮件按重量分档后，进行不同的计价标准计费。 5、解二元一次方程组 要求：填入标准的二元一次方程组的系数，可以立即得出解。（如方程组为：ax+by=m,cx+dy=n, 给定a,b,c,d,m,n的值，立即可以解出x= ,y= .） 6、个人日常物品管理 要求：对个人的日常物品进行管理，便于查找和提示等。 7、其他 要求：按照自己的思路，设计一个利用excel实用方案。
The Harm and Solution of the Haze
The Harm and Solution of the Haze Economy has an increasingly development in China, which brought us a lot of benefits, but evoked some problems. One of the most serious problems is pollution. Recently, haze has affected many cities in China, which has drawn widespread attention. There is a famous video made by Chai Jin, to show some factors and opinions about haze. After watching the radio, I think we have to realize that the harm of haze and how to reduce the haze. It is obvious that haze could bring us all kinds of harm. First, haze made bad effect on our health. In some cities with haze weather, more and more people develop disease such as asthma, allergy, and pneumonia and lung disease.Secondly, haze could make bad effects on the traffic because haze reduces our vision. In heavy haze weather, traffic jam is usual since drivers have to keep slow to avoid to accident. The haze weather also has a variety of impacts on agriculture. The haze could hinder plants from photosynthesis since the dust reduces the light. So the plants can't grove well and even wither. To reduce the harm from the haze, we have many effective measures to do.As far as government is concerned, they have to introduce practical policies and put into effect. They should close the factories that produced too much industry exhaust. They should plant trees as many as possible. They should also try to limit the number of private cars since automobile exhaust plays an important role in casing haze. What's more, it is our duty and obligation for citizen to do something for reducing the haze. We could choose public vehicles and bicycle instead of private cars. We could use clean energy instead of coal and firewood. Facing the haze, we have to think what harm we are suffering and realize that Chinese are living with danger. Then, government and civilian should tack action to reduce haze from now on.
完成阶段审计2 试题
完成阶段审计2 试题
一、单选题 1、在资产负债表试算平衡表中，各资产项目的期末审定数为（）。 A.期末未审数+账项调整借方-账项调整的贷方 B.期末未审数-账项调整借方+账项调整的贷方 C.期末未审数+账项调整借方-账项调整的贷方+重分类调整借方-重分类调整贷方 D.期末未审数-账项调整借方+账项调整的贷方-重分类调整借方+重分类调整贷方 【答案】C 【解析】资产的期末审定数等于期末未审数加上账项调整借方减去账项调整的贷方加上重分类调整借方减去重分类调整贷方。 2、项目组内部最高级别的复核是（）。 A.项目负责经理现场复核 B.项目合伙人的复核 C.独立的项目质量控制复核 D.项目组内成员间的复核 【答案】B 【解析】项目合伙人的复核是项目组内部最高级别的复核。
3、A注册会计师2011年3月25日完成对Y公司2010年度财务报表的外勤审计工作，2011年3月26日取得Y公司管理层书面声明，2011年3月30日完成并签署报告，2011年4月2日将审计报告送交Y公司报出。则Y公司管理层书面声明的日期通常是（）。 A.2011年3月25日 B.2011年3月26日 C.2011年3月30日 D.2011年4月2日 答案：C 解析：管理层书面声明的日期通常与审计报告日一致。 4、下列有关财务报表日至审计报告日之间发生的期后事项的说法中正确的是（）。 A.因为这个阶段已经不属于注册会计师所审计年度的事项，无须关注 B.注册会计师没有责任针对财务报表实施审计程序进行专门查询 C.注册会计师应当实施必要的审计程序，获取充分、适当的审计证据以主动识别该期后事项
个人工作完成情况总结
个人工作完成情况总结 xx年上半年个人工作任务及完成情况 作为一名进入郫县“一村（社区）两名大学生”这个大家庭一年半的成员来讲，对这项工作从陌生到了解再到熟悉经历了一个漫长的过程，这当中也遇到了很多困难，但是在各个镇领导的帮助与鼓励下也收获了许多，学习到了许多。在犀浦镇政府服管办的一年时间里，我慢慢熟悉了我们办公室的工作内容及工作形式；但从犀浦转向安靖镇政府，虽然都是政府办公，但每个政府单位的环境不同、实际的工作内容不同、领导方式不同，这又让我进入了一个陌生的工作环境。在这里，我又被分到了一个不一样的办公室——安全生产办公室，同时又分配到了方碑村，职务是村主任助理，虽然在这里的一切都是陌生的，但是这里的领导是热心的，在他们的不断关心与支持下，我渐渐的进入了正常的工作轨道。到现在半年时间，我基本上了解了安办的工作内容和工作目标，对领导安排的工作也能够得心应手，与此同时也让我建立起了为郫县、为安靖镇服务的信心。现将这半年的工作目标及完成情况总结如下： 一、加强政治业务学习，不断提高自身素质。 半年来，认真学习贯彻“毛泽东思想，邓小平理论， __重要思想”的精神，不断的提高自身政策理论水平，政治敏感性和政治鉴别力不
断增强，进一步加深了对“ __”重要思想和科学发展观、安全发展理念内涵的理解，进一步坚定了理想 信念，强化了宗旨观念和纪律观念，增强了党性修养，改进了思想作风、学风、工作作风、领导作风、生活作风。通过一系列学习，提高了履行职能、依法行政的业务素质。 二、认真贯彻落实上级部署 坚决贯彻落实市、区（县）重大决策和重要工作部署。结合本部门工作实际，协助镇领导及时研究、制定切实可行的贯彻措施，确保政令畅通和各项工作落到实处，并按要求及时反馈贯彻落实情况。 三、xx年上半年所做工作及完成情况 （一）完成办公室的文字工作，档案收集工作，办公室人员接待工作，会议记录工作等； （二） xx年3月，协同我办领导对安靖镇的锅炉使用情况进行了为期一个月的摸底检查，其中摸排出锅炉使用户71户，并对锅炉使用过程中的违规现象提出整改要求。
The cause of the haze雾霾原因(英语)
The cause of the haze There are many reasons for the formation of haze, among them, as far as I'm concerned, there are five cases playing more important roles than others. First of all, the atmospheric air pressure is low and the air doesn’t flow, so that the small particles in the air are all accumulated, and then they will be floating in the air. This is the main factor of all. Second, there are a lot of dust on the ground and the air humidity is low, people and traffic flow make the dust stirred up. Third, automobile exhaust is the main pollutant emissions, in recent years, since the number of the cars has increased largely in the city , automobile exhaust emission is gradually becoming one of the main factors in the formation of haze. The fourth reason lies in those factories which produce pollution. At last, winter heating has increased CO2 emissions and other pollutants. In most northern cities, the winter heating is inevitable, for which we are obliged to burn more fuel. As we all know，the energy we used mainly derived from non-renewable resources such as oil, coal and natural gas. Burning coal will lead to air pollution and endanger public health. the situation in some northeastern cities is even worse , where people have to suffer from serious haze problem.
工作完成情况报告
人劳科2010年工作责任目标完成情况报告 2010年人劳科按照县局（分公司）工作目标管理要求，在上级领导的关心下，在兄弟部门的配合支持下，圆满完成了本单位的工作计划。现将2010年工作责任目标完成情况报告如下： 责任目标之一：完善系统工作考勤制度和工资审批制度，确保工资全额按时发放 工作完成情况：认真制定好工资发放计划，对职工工资的发放统一实行一支笔审批制度，确保在市局下达的工资计划内管理好，使用好工资。截止2010年12月25日，系统2010年工资已全额兑现，内退人员生活费和离退休人员的自建补贴也已全额发放结束。 责任目标之二：确保系统养老金、医保金、住房公积金、计算准确，个人账户足额到户，并定时公示 工作完成情况：圆满完成了养老金等的缴纳工作，全年缴纳各项资金共计1091.6万，其中养老金454万，失业保险金14.7万，医疗保险金179.2万，住房公积金424.7万，在职职工工伤保险金5.8万，离休人员医药费13.2万。 责任目标之三：加强对离退休人员的管理工作 工作完成情况：遵照上级有关文件精神要求，加强对离退休人员的管理工作。截止2010年12月底，共办理职工退休20人。 近年来，我们行业的退休和内退人员逐年增多，截止2010年12月底，系统共有离退休人员380人，内退人员81人，计461人。为了充分体现企业对老干部、老同志的关怀，2010年以来，我们在做好系统老干部工作方面投入了大量的精力。2010年春节前，人劳科按照县局（分公司）安排，积极组织人员，备足了慰问品，冒着风雪寒冷，县内县外，走村串户，亲切的把公司党委和干部职工的美好祝福和爱心及时送到了每个老干部、老同志的家中，使他们过上了祥和愉快的节日。并与建军节前夕对18名退休军转干部进行了慰问。通过春节慰
酒精溅身上怎么去灭火
女生吃烧烤时被酒精烧伤酒精溅身上怎么去灭火 2014年09月09日09:05:50 来源：温州网王雄涛王志军 浙江在线09月09日讯 9月2日，温州大学大二女生应小倩在义乌一家烧烤店吃饭时，不幸被酒精严重烧伤。当时，小倩同学用衣服上前拍打救火，但效果并不明显。那么顾客在遇见酒精着火后，应该选择哪种救火方法？昨天，温都记者在鹿城消防分局消防宣教员王志军的帮助下，进行了灭火实验。 实验目的：遇见酒精着火，哪种灭火效果最好 实验材料：四块带皮猪肉(模仿人体肌肤)、两瓶500毫升浓度75%的医用酒精、一个干粉灭火器、一小盆清水、一罐小型家用水喷雾灭火器、一个开口半截铁桶、一块湿桌布、一个铁制托盘、打火机和餐巾纸。 方法一 酒精燃烧后，用水灭火 酒精燃烧后，直接用水上前救火的效果如何？将一块10平方厘米的带皮猪肉放在铁制托盘中，再将其放在开口铁桶中，将铁桶放在地上，在肉上浇了200
毫升医用酒精，点燃后酒精很快燃烧，猪肉也发出“吱吱”的声音，十几秒以后，消防员拿来一小盆清水直接倒上去。 这时，只见猪肉上燃烧的酒精四散开来，火焰根本没有熄灭。直到托盘中的酒精完全燃烧后，火焰才熄灭。 消防解释：身上沾有燃烧的酒精，如果直接用清水扑救的话，会使燃烧面积增大，引发其他部位燃烧，不利于灭火。 方法二 酒精燃烧后，用干粉灭火器灭火 义乌消防说，如果能及时用干粉灭火器灭火，小倩的烧伤可能不会那么严重。那么酒精燃烧后，干粉灭火器灭火效果如何？ 拿一块10平方厘米的带皮猪肉放在铁制托盘中，再将其放在开口铁桶中，将铁桶放在地上，随后在肉上浇200毫升医用酒精，点燃后，酒精很快燃烧起来。十几秒以后，消防员拿来干粉灭火器上前灭火，消防人员只喷了两下，整个铁桶中的大火就被扑灭，猪肉表皮烧伤严重，但肌肉烧肉不严重。美中不足的是，猪肉表皮上沾满干粉。 消防解释：实验表明干粉灭火器的灭火效果比较明显。饭店里大都有干粉灭火器，因此顾客遇见酒精燃烧时，可使用干粉灭火器。店家要将干粉灭火器放在醒目位置，并要教会店员如何使用。 方法三 酒精燃烧后，用小型水喷雾灭火器灭火
需要大家完成的工作
毕业设计需要完成的任务及各种注意事项,请大家认真阅读 设计说明： 特别提醒：近年对毕业设计要求严格，设计题目三年不能重复，内容重复率不能超过30%，所以大家一定要认真通读全文，并按照自己的语言重新表述，防止重复率过多，将来上级检查中如果重复率超标，将对毕业设计者给予处分，最严重可能会取消毕业设计成绩，大家切记，不能应付了事。 温馨提示：毕业设计结束时间日趋逼近，大家要对自己负责，抓紧吧！ 1. 通读全文，对全文作简要总结， 2. 完成“毕业设计手册”中“毕业设计任务书”、“开题报告”内容，尽量写满，学校近期要检查——这是近期最着急的任务。“毕业设计任务书”中参考文献要求是根据毕业设计查找最接近的参考文献，不少于15篇，要求近5年的资料，参考文献格式在“毕业论文格式”中有明确规定；毕业设计手册按照我给的范本,结合你自己的设计题目和内容重新撰写,但不要提前打印,在答辩后检查通过再打印. 3. 设计题目以我给你们的为主，将资料中所有出现的设计题目修改过来。自拟题目也要求所以资料题目一致统一。 4. 按照毕业设计题目，查找3000字左右与毕业设计题目相关的中文资料，然后翻译成英文，做成word备用；注意：百度翻译等软件翻译后要斟酌，不能出现语法错误。——这是近期最着急的任务。 5. 按照学院毕业设计格式将论文资料重新整理，包括字体、字号、
页边距、纸型、页眉页脚、封面; 6. 通读全文，对全文作简要总结，撰写中文摘要和相对应的英文摘要（不少于300字），中英文严格对照; 7. 论文或说明书中参考文献要增加至35篇，要求和你本课题相关的参考书、期刊论文、设计手册、设计软件书等文献资料，并在论文中应用该文献的位置用“上角标”标注出来，至少1篇外文文献.可以查找CNKI的资料. 例：题目:PLC电梯控制系统设计 标注方法: PLC将会继续失去市场份额甚至被完全取代[4]， 参考文献中的[4]应该是和PLC 相关的参考资料 8. 对照毕业设计格式，查缺补漏，看你的设计资料是否齐全; 9. 全部设计内容要求在5月1日前必须完成，完成后与我联系，将资料发到我QQ邮箱，我在检查合格后允许打印。 10. 最后将所有文字资料合为一个文件，包括论文、中文摘要、英文摘要、目录、正文、参考文献、致谢等环节. 11. 毕业设计图纸至少折合2-3张0号。说明书不少于1.5万字 12. 毕业设计结束后，每人将自己的设计资料全部刻成一张光盘上交。 打印说明： 1、设计说明书：A4纸打印，然后裁减成16K，单面打印，装白色布纹纸封皮（学校附近印刷厂、打印社等可以实现）
项目完成工作情况总结五篇
项目完成工作情况总结五篇 工作总结怎么写?总结是对已经做过的工作进行理性的思考。它要回顾的是过去做了些什么，如何做的，做得怎么样。下面给大家整理了关于项目完成工作总结，方便大家学习。 项目完成工作总结1 一、__年主要工作： 1、“凯晨世贸中心竣工长城杯”创优(__年3月7日～__年6月)： 负责通风、空调、给排水、消防等专业的创优工作，协调业主及物业公司，组织原相关专业施工单位，依据“北京市竣工长城杯”标准对工程实体及内业资料进行整改、完善，并同步完成了对“凯晨物业”的移交工作。 __年7月，经评定，凯晨世贸中心获“北京市竣工长城杯金奖”。 2、光华世贸中心(__年6月～7月2日) a.配合商务部门完成光华世贸中心d座通风专业的对业主方的竣工结算工作。
b.协同赤几前方，完成“马拉博国际会议中心项目”通风、空调专业初设图纸的会审和空调水工程量的统计工作。 c.协助机电经理，完成《项目策划――马拉博国际会议中心(机电部分)》的编制。 3、赤几马拉博国际会议中心(__年7月3日到达赤几) a.协助机电经理，协调中建国际c板块(采购部)及其它相关部门，依据赤几公司及会议中心项目部的要求，完成第一批进场物资的请款及相关工程物资及施工机具申请计划的编制或审核。 b.协调西南院设计，对设备参数等设计图纸细节问题进行协商、确认。 c.鉴于成本角度考虑，建议西南院设计调整了部分管材、保温等材料。 d.协同中建国际qs板块(成本、测算部)，完成《机电固定总价部分成本预算初稿》的编制。 e.协助会议中心项目商务部门完成第一批机电到港物资的 清关手续的办理及到港物资的清点及运输协调工作，并针对过程中发现的问题，对公司采购部门提出了具体的建议和要求(详见附件1《对船运物资控制的几点建议》)。
ENVI去云补丁Haze Tool使用说明
Haze Tool User Guide 使用方式 (2) 云层厚度检测 (2) HOT13 (2) 操作步骤 (3) HOT123 (4) 操作步骤 (4) 案例 (5) 云层厚度完善 (8) Haze perfection TM (9) 操作步骤 (9) Haze perfection QB (11) Maskandinterpolation (12) 案例 (13) Thresholdandinterpolation (13) fill_sink (14) flatten_peak (15) 操作步骤 (15) 云层去除 (17) Dark Substract (17) 操作步骤 (20) Hist match (22) 操作步骤 (22) Cloud Point (22) 操作步骤 (23) 案例 (28) 鸣谢 (29) 引文 (29)
使用方式 该模块是在ENVI4.4中二次开发而成。使用时只需将文件置于***\ITT\IDL64\products\envi44\save_add文件夹内，然后运行ENVI，Basic Tool菜单中会出现一个Haze tool按钮。绝对不要修改文件名，否则无效。 Haze tool主要由三部分组成：云层厚度检测（haze detection），云层厚度完善（haze perfection），云层去除（haze removal）。这三部分前后连贯，每一步的结果都会影响到最终的除云效果，而且在参数的选择上主观性较大，这也是这个模块的缺点即不够自动化。 有问题联系作者请加QQ：27126797 或者e-mail联系：whogamble@https://www.wendangku.net/doc/d510095393.html, 除云案例请见作者博客：https://www.wendangku.net/doc/d510095393.html, 云层厚度检测 一副影像中往往云层厚薄不一，因此不同厚度云覆盖下的地表需要恢复的强度不一；当然，完全遮挡地面的厚云不在考虑范围内。在该模块中云层厚度检测有两个指数：HOT13和HOT123。两者都是相对厚度检测，而不是绝对的光学厚度检测，HOT123是作者在HOT13的基础上的改进。 HOT13 HOT13由加拿大遥感研究中心的Zhang ying提出的(Zhang et al. 2002) （原称HOT，13是作者加上去的以示与HOT123的区别）。根据地物在蓝色（TM1）和红色（TM3）波段的高度相关性，在特征空间里绝大部分像素分布在晴空线上。云的存在会使得云下地物的光谱偏离这条晴空线，云越厚，偏离越大。HOT13等于偏移距离。
【数字电子技术基础实验】阶段完成的任务
阶段完成的任务： 一、TTL门电路的逻辑功能测试及其应用（第一章和第三章） 1、与非门74LS00的逻辑功能测试 实验电路： 拷贝Multisim电路原理图-输入采用开关、实际搭接电路的图片 输出采用发光探针 实验结果：（word编辑） 与非门74LS00逻辑功能测试 2、非门74LS04和异或门74LS86的逻辑功能测试 实验电路：（要求同上）
实验结果： 非门74LS04逻辑功能测试 异或门74LS86逻辑功能测试
3、楼道顶灯控制电路的设计 楼道中的一个电灯L，由A、B、C三个开关控制，要求任何一个开关都能控制该灯的亮和灭，试用与非门设计一个控制该灯的逻辑控制电路。要求写出逻辑抽象，列出真值表，写出逻辑表达式，画出电路图，写出与非-与非表达式，画出与非逻辑电路图。Multisim 仿真时采用逻辑转换器，拷贝Multisim与非-与非电路原理图、逻辑转换器的仿真结果；拷贝实际搭接电路（原始表达式）的图片，并列表记录实测结果。
二、组合逻辑器件的应用（第三章） 1、三线-八线译码器74LS138的应用 设计一个三路报警电路，当第一路有报警信号时，数码管显示为1；当第二路有报警时，数码管显示2；当第三路有报警时，数码管显示3；当两路或两路以上有报警信号时，数码管显示4；当无报警信号时，数码管显示0。要求：用74LS138和与非门设
计此电路，写出设计过程，画出逻辑电路图，Multisim 仿真时输入采用字信号发生器，拷贝Multisim 电路原理图和实际搭接电路的图片，并列表记录仿真结果和实测结果。 2、四选一数据选择器74LS153的应用 利用74LS153实现逻辑函数，函数的输入变量A 、 B 、 C 分别接逻辑电平输出开关，输出端Z 接发光探针显示。要求写出设计过程，画出逻辑电路图，根据所设计的电路连接实验线路，拷贝Multisim 电路原理图和实际搭接电路的图片，并列表记录仿真结果和实测结果。 Z ABC ABC ABC ABC =+++
如何有效完成工作计划
如何有效的按时完成工作计划 一、首先要制定一个有效的、严谨的、可量化的、合理的工作计划。 1、制定工作计划的程序。 周五晚下班前店总/公司副总组织参加公司周会的管理人员总结上周未完成工作，并汇总下周工作计划周六早上参加公司大周会（必须要认真倾听、用专用笔记本做笔记、专职文员做记录并录音）周六中午店总/公司副总组织参会人员讨论学习会议内容，整理出初步的工作计划由文员打印出工作计划交由店总/公司副总审核各店面/部门周六晚10：00前必须把电子版工作计划上交公司人事部人事部在周日中午12：00前把各店面/部门的工作计划整理完毕后上交公司总经理审批公司总经理审批后由人事部在周日晚9：30前下发到各店面/部门负责人手中（文字版+电子版）。 2、怎样写工作计划。 2.1最重要的工作计划内容要加粗、加黑（最多三项），并要写在 计划的最前面一看就知。 2.2上周未完成的工作计划要放在“最重要的工作计划”下面，并 在备注栏用“★”标注。 2.3 区分职责、计划、目标的区别，按标准填写工作计划（职责是 定性的、定方向的，职责是“做什么”；计划是可细化的具体工 作步骤，计划是“怎么做”；目标是定量的、可量化、可考核的，目标是“做到什么程度，达到什么样的结果”）。 2.4工作计划的目标来源： A 岗位职责（本职工作） B 上级安排工作 C 客户需求 D 其它工作安排和应急事项 2.5经营、管理、培训各项工作计划要分开写，各单独写一页，并 都要从第“1”项开始。
二、有效的完成工作计划的必要条件 1、店总/公司副总在周一晚下班前必须主持开完酒店/主管部门周 会。由店总主持的酒店周会主管级（前厅/厨房）及以上级别管理人员和后勤员工代表 (职餐员、宿管员、洗碗工)必须参加，并适当要求酒店骨干员工参加酒店周会，参会人员不低于15人（要让尽可能多的人参加周会，培养他们的管理意识和参与意识，提高他们的综合素质，让他们感觉到被重视，让他们在工作中更具激情和活力）；由公司副总主持的二线部门周会必须全员参与（财务可财务经理1人参加）。 2、公司各分部门周会由各分部门负责人主持，必须在周三晚下班 前全部开完。 3、计划要分工明确，责任到人，专人提醒（电话、当面或短信提 醒，可用飞信软件），计划要贴到公共区域，要全员知晓、全员参与。 4、每天碰头会必须带上工作计划，计划总负责人要要每日协调、每 日沟通、每日催进（计划不是放在夹子里到周五才拿出来看的东西）。 5、工作计划在完成时要用笔划掉，不能按时完成的应立即调整确定 完成时间并对相关责任人做好通知和要求。 6、工作计划的总负责人要及时与上级、下级做好沟通，做到对计划 的完全掌控；每项计划都要有专人替补，不能因人而随意变动。 7、把每周、每月都固定的重点工作要做成固定计划（计划必须严谨、 合理，要与公司各项计划要求一致，并加上自己部门职能内的工作计划），计划要上墙，由专人提醒，不按计划做的要做好自罚，把完不成计划接受处罚形成一种习惯。 8、工作计划在开周会当周周五未完成的，要提前用红笔勾勒出来， 并提前做好总结。 9、周六开公司周会汇报的下周工作计划内容不是周五才开始想的， 下周工作计划是每时、每日提前不断积累好的。