Chapter17
Plant Nutrient Phytoremediation Using Duckweed Louis Landesman,Clifford Fedler,and Runbin Duan
Abstract Over the last40years a great deal of research has been published on the use of duckweed to treat wastewater both from point sources(feedlots, food processing plants)and from non-point sources. These plants can recover nutrients such as nitrogen and phosphorus from contaminated waters in those agricultural practices.They can also remove or accu-mulate metals,radionuclides,and other pollutants in their tissues.In addition,the duckweed can be used as a feed source for livestock and poultry as well as an energy source for biofuel production.A summary of some of the published work done using duckweed species to phytoremediate natural,domestic,industrial, and agricultural wastewaters is presented. Keywords Duckweed·Plant nutrients·Phytoremediation·Lemnaceae·Lemna·Wolf?a 17.1Introduction and Background
of Duckweed
Duckweeds belong to the arum family Araceae,sub-family Lemnoideae,a family of?oating,aquatic plants.This family consists of?ve genera with at least40species identi?ed as of1997(Les et al. 2002).Duckweeds are among the smallest and sim-plest?owering plants,consisting of an ovoid frond a https://www.doczj.com/doc/1018746318.html,ndesman( )
Virginia Cooperative Extension,Virginia State University, Petersburg,V A23806,USA
e-mail:llandesman@https://www.doczj.com/doc/1018746318.html, few millimeters in diameter and a short root usually less than1–cm long(Fig.17.1).The frond represents a fusion of leaves and stems and represents the max-imum reduction of an entire vascular plant(Landolt 1986).Some species of the genus Wolf?a are only 2mm or less in diameter;other Lemna spp.have frond diameters of about5–8mm.The largest species of Lemnaceae have fronds measuring up to20mm in diameter(Spirodela sp.).The minute?owers are rarely found in most species.Under adverse conditions such as low temperatures or desiccation,modi?ed fronds called turions appear which sink to the bottom of the water body.These turions can resurface at the onset of favorable conditions of light,moisture and temperature to start new generations of duckweed plants(Hillman 1961,Perry1968).Because?owering in Lemnaceae is rare,reproduction normally occurs by budding from mature fronds.The tolerance of Lemnaceae fronds and turions to desiccation allows a wide dispersal of Lemnaceae species.This low level of gene?ow and infrequent sexual reproduction has produced substan-tial levels of genetic divergence among populations, despite an absence of morphological differentiation (Cole and V oskuil1996).However,asexual reproduc-tion in Lemnaceae allows for rapid reproduction in this family.Occasionally extreme weather events,such as unusually high summer temperatures,can cause mass ?owering(Bramley1996).Usually?owering has to be induced with plant hormones or photoperiod manip-ulation(Cleland and Tanaka1979).All Lemnaceae ?owers are minute and barely discernable without magni?cation(Landolt1986).
Due to its ease of culture and worldwide distribu-tion,a tremendous literature exists on duckweed ecol-ogy,physiology,production,and https://www.doczj.com/doc/1018746318.html,ndolt and Kandeler’s two monographs on Lemnaceae are the
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DOI10.1007/978-90-481-9625-8_17,?Springer Science+Business Media B.V.2011
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Fig.17.1Spirodela (large ),Wolf?a (small ),and Lemna (intermediate )
most comprehensive works on Lemnaceae and list vir-tually all published works up to 1986(Landolt 1986,Landolt and Kandeler 1987).In addition there are sev-eral web sites that have more updated information on duckweed biology and applications (Cross 2007,Landesman 2008).
The genera Lemna ,Spirodela ,and Wolf?a of the family Lemnaceae play an important ecological role in lakes,ponds,and wetlands.They often are an impor-tant source of food for waterfowl (Krull 1970)and aquatic invertebrates.The outer margins of duckweed fronds (phyllosphere)support dense populations of diatoms,green algae,rotifers,and bacteria (Coler and Gunner 1969).Associated with this epiphytic commu-nity is an assortment of insects,including beetles,?ies,weevils,aphids,and water striders (Scotland 1940).Some of these insects may become abundant enough to affect the duckweed population.Together with the frond biomass this microfauna enhances the nutritive value of duckweed to grazing animals such as ducks,geese,nutria,turtles,coots,?sh,and snails,all of which have been recorded as feeding on duckweed.Duckweed populations are limited mostly by light,nutrients,and temperature (Hillman 1961).Duckweed populations can grow very densely in nutrient-rich environments,so much so that layers of fronds grow one on top of another to form a mat that can be up to 6–cm thick.This thick mat creates an anaerobic envi-ronment in the water body on which this mat ?oats,thus promoting anaerobic digestion and denitri?cation of the water body in which the duckweed grows.Since duckweed ?oats freely on water surfaces,strong winds can sweep fronds from the water surface.
The presence of duckweed in an aquatic envi-ronment has both direct and indirect effects on that environment.When duckweed is abundant enough to completely cover a pond,ditch,or canal,this layer of opaque fronds can shade out rooted aquatic macro-phytes (Janes et al.1996)as well as reduce phyto-plankton abundance.In eutrophic environments such as the polders of Holland,Lemna sp.can form a climax community that prevents Chara and other submerged macrophytes from getting established (Portielje and Roijackers 1994).A complete cover of duckweed on the water surface can lead to the creation of an anaero-bic environment in the water column,which in turn can make that water body inhospitable to ?sh and aquatic insects (Pokorny and Rejmankova 1983,Leng et al.2004).
The presence of duckweed can contribute to the organic matter present in a water https://www.doczj.com/doc/1018746318.html,yers of Lemna minor L.excrete amino acids and humic substances into the aquatic environment which can provide nutrients to other organisms such as bacte-ria,epiphytic algae,and indirectly to snails,spring-tails,isopods (Asellus sp.),and other microdetrivores (Thomas and Eaton 1996).Dead and dying duck-weed fronds fall to the bottom of the water column where their decay contributes organic matter,nitro-gen,phosphorus,and other minerals to the benthos (Laube and Wohler 1973).In addition cyanobacteria residing in the phyllosphere of duckweed fronds can
17Plant Nutrient Phytoremediation Using Duckweed343
?x atmospheric nitrogen,providing a nitrogen input in oligotrophic environments(Tran and Tiedje1985). This can be an important source of nutrients in aquatic environments.
Duckweeds are among the fastest growing aquatic angiosperms in the world,frequently doubling their biomass under optimum conditions in2days or less (Culley et al.1981).Based on growth rates recorded in the literature,duckweeds can grow at least twice as fast as other higher plants(Hillman1978).Depending on the genus,duckweed daughter fronds are produced vegetatively in pairs(Lemna and Spirodela)or as a daughter frond from the basal end of the mother frond (Wolf?a).Each daughter frond repeats the budding history of its clonal parents,resulting in exponential growth(Landolt1987).Lemna,Spirodela,and Wolf?a, three important genera of Lemnaceae,are all subject to self-shading(intra-speci?c competition)and reach a steady–state condition where frond death equals frond multiplication.Hence Lemnaceae is subject to density-dependent growth(Ikusima1955,Ikusima et al.1955). Once essential nutrients are depleted or waste products build up,the growth rate declines.
When duckweed was cultured in axenic(ster-ile)conditions using chemically de?ned media under arti?cial lights,growth rates were recorded that far exceeded growth rates measured under natural con-ditions(Hillman1961).Excessively high light lev-els(more than200Wm–2),nutrient shortages,and the presence of herbivores,parasites,and commen-sal organisms antagonistic to duckweed populations greatly reduce the growth rates of duckweeds in natural environments(Landesman2000).Duckweed growing in wastewater treatment plants,however,is under less pressure from herbivores because the high ammonia and low dissolved oxygen levels prevalent in wastew-ater may exclude potential grazers such as?sh and turtles.Wastewater environments also have abundant supplies of nitrogen and phosphorus as compared to natural aquatic environments.
17.2Duckweed for Phytoremediation
of Contaminated Waters Phytoremediation is de?ned as the method to utilize higher plants to alter contaminated envi-ronments.It is a cost-effective,low-impact,and environmentally sound remediation technology (Cunningham and Ow1996).And phytoremedia-tion includes?ve different mechanisms,which are rhizo?ltration,phytostabilization,phytoextraction, phytovolatilization,and phytotransformation(Ghosh and Singh2005).Rhizo?ltration is that plants are used to absorb,concentrate,and precipitate contami-nants from polluted aquatic environment by their roots; phytostabilization involves the stabilization of contam-inated soils by sorption,precipitation,complexation, or metal valence reduction rather than the removal of contaminants;phytoextraction,also referred as phytoaccumulation,is the process that plants absorb, concentrate,and precipitate the contaminants in the biomass;phytovolatilization is the mechanism that plants extract certain contaminants in nearby roots and then transpire them into the atmosphere;phy-totransformation,also referred as phytodegradation, is the process that plants remove contaminants from environment by their metabolism.More detailed infor-mation on these?ve different mechanisms is listed into Table17.1.
17.2.1As an Alternative Means
of Wastewater Treatment Duckweed has been utilized in the treatment of munic-ipal and industrial wastewaters for more than two decades,which can be traced back to before1990 (Oron et al.1988).Duckweed is widely and effectively used for phytoremediation of contaminated water due to its ability to grow at wide ranges of temperature,pH, and nutrient level(Landolt and Kandeler1987)in areas where land is available for its application(Krishna and Polprasert2008).Considerable work was done in the 1970s and1980s on the use of duckweed genera,espe-cially Lemna,as a means of treating wastewater of both agricultural and domestic origin.When Lemna is grown in wastewater treatment ponds the?oating mat of fronds is held in place by partitions and baf?es that prevent wind from blowing fronds to one side off or completely off the surface of the treatment pond.These partitions and baf?es are usually made of polyethy-lene in industrialized countries but may be made of bamboo or other natural materials in developing countries.
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Table17.1Contaminant removal processes and mechanisms by phytoremediation
Rhizo?ltration Phytostabilization Phytoextraction Phytovolatilization Phytotransformation
Mechanism Rhizosphere
accumulation,
absorption,
concentration,
precipitation Complexation,
sorption,
precipitation,
metal valence
reduction
Hyper-
accumulation,
absorption,
concentration,
precipitation
V olatilization Degradation by plant
metabolism
Contaminant Organics/
inorganics,
Pb,Cd,Cu,Zn,
Cr,Ni Inorganics,heavy
metals
Inorganics,heavy
metals
Organics/
inorganics,Hg,
Se
Organics,
ammunition
wastes,chlorinated
solvents,
herbicides
Environment Industrial
discharge,
agricultural
runoff,acid
mine drainage Soil,sediment,
sludge
Diffusely polluted
areas
Soil,water,
sediment
Soil,water,
groundwater
Reference Chaudhry et al.
(1998),USEPA
(2000),Ghosh
and Singh
(2005)Mueller et al.
(1999),USEPA
(2000),Ghosh
and Singh
(2005)
Rulkens et al.
(1998),USEPA
(2000),Ghosh
and Singh(2005)
Ba?uelos(2000),
Henry(2000),
Ghosh and Singh
(2005)
Black(1995),Ghosh
and Singh(2005)
As part of a facultative treatment system,duckweed can cover treatment ponds and reduce the growth of algae in these ponds as well as reduce nitrogen in the ef?uent from these ponds through ammonia uptake and denitri?cation(Alaerts et al.1996;Hammouda et al.1995).Duckweed can also be part of constructed wetland systems,either as a component of a wetland receiving wastewater or as plants that polish nutrients from wetland-treated ef?uents(Ancell1998,Fedler et al.1999,WEF2001).
Harvesting wastewater-grown duckweed helps to remove surplus nutrients,which might otherwise be released into aquatic environments by wastewater treatment plants(Harvey and Fox1973,Oron et al. 1988).Duckweeds,like other plants,take up nutri-ents from their surrounding environment(Landesman 2000).This ability has been exploited to remove sur-plus nutrients from swine lagoon ef?uents(Cheng et al.2002b).The growing plants can then be harvested to remove surplus nitrogen and phosphorus.However, the application of duckweed in recovery(Cheng et al.2002a)and removal of nitrogen and phosphorus in swine lagoon water was found to be subject to the water concentrations and seasonal climate since the primary mechanism is assimilation of those nutri-ents in environment;therefore,the appropriate light intensity and preferable temperature are key param-eters for duckweed in removal of surplus nutrients (Cheng et al.2002b),and duckweed prefers to take up NH4+than NO3-by both roots and fronds(Fang et al.2007).
Duckweed populations can remove nutrients from stormwater ponds.A monoculture of L.minor con-sistently removed a large amount of ammonia from stormwater while a mixture of L.minor and Spirodela polyrhiza removed the largest amount of phospho-rus from stormwater within8weeks of treatment (Perniel et al.1998).Recently,Drenner et al.(1997) have described a system for culturing periphyton on eutrophic ef?uents and raising?sh that graze on this wastewater-grown periphyton.In this way,surplus nutrients are concentrated in?sh?esh.A similar sys-tem could be designed using duckweed as the nutrient stripping plant(van der Steen et al.1998).
Duckweed systems can remove50–60%of nitro-gen and phosphorus(Vatta et al.1994)from domestic wastewater or even73–97%of total Kjeldahl nitrogen and63–99%of total phosphorus in duckweed-covered domestic wastewater(K?rner and Vermaat1998). The removal of chemical oxygen demand(COD)is faster in duckweed-covered domestic wastewater than uncovered wastewater,and organic degradation can be improved by additional oxygen supply and addi-tional surface in duckweed-covered domestic wastew-ater(K?rner et al.1998).The removal ef?ciencies can be reached at high to84,88,68,58,and87%
17Plant Nutrient Phytoremediation Using Duckweed345
for COD,BOD5,NH3-N,TN,and TSS,respec-tively,in duckweed-based wastewater treatment sys-tem under optimum operating and environmental con-ditions(Krishna and Polprasert2008).Furthermore duckweed systems evaporate20%less water com-pared to other open water wastewater treatment systems(Oron et al.1986,Borrelli et al.1998). The reduced evaporation of duckweed-covered sur-faces in wastewater treatment is an asset in arid climates.
Guidelines for the use of duckweed to remove ammonia and phosphorus from ef?uent from an algae culture system were given by Koles et al.(1987). Researchers at the Politecnico di Milano,Italy,have developed models for duckweed-based wastewater treatment plants(Boniardi et al.1994,Rota et al. 1995).These models will greatly assist in the design and management of duckweed-based wastewater treat-ment systems(Landesman et al.2005).Duckweed-based treatment systems have their limitations.They require large areas of land that may not be avail-able near urban areas.In temperate climates duckweed growth slows in the winter.This may restrict the use of such treatment systems in cooler climates unless a greenhouse system is utilized.Duckweedbased treat-ment systems may be most useful in treating secondary ef?uents from small communities where land costs are low(Bonomo et al.1997).
A series of investigations on duckweed application in restoration of eutrophic water were done in the past decades.Eutrophic water is associated with exces-sive nitrogen and phosphorus in water input by dis-charge from agricultural wastewater,industrial water, and domestic water.Eutrophic water had the risk of eutrophication de?ned as the negative effects of the excessive growth of phytoplanktons(Khan and Ansari 2005),degradation of water ecosystems,or even dis-appearance of the water body involved in.Duckweed was used to remove the targeted nutrients in eutrophic water due to its ability to survive in nutrient-laden envi-ronments and its rapid growth(Li et al.2009)so that those nutrients can be removed by harvesting duck-weed biomass(Li et al.2007)and eutrophic water can be recovered by combining other technologies.The duckweed L.minor is suitable for phytoremediation of eutrophic waters at acidic pH and at temperature from20to30?C(Ansari and Khan2008);however, the duckweed S.polyrhiza cannot be used to recover the eutrophic waters at low temperature of10–12?C (Song et al.2006).Many mathematical models have been developed for duckweed systems to describe its phytoremediation of eutrophic waters(Frédéric et al. 2006);those models incorporated duckweed growth parameters including temperature,photoperiod,nitro-gen concentration,phosphorus concentration,and mat density(Lasfar et al.2007).
17.2.2As a Means of Removing Heavy
Metals and Other Toxic Elements
in Waters
Heavy metals are readily accumulated and transported in aquatic environment in the form of dissolved or solid wastes from domestic,industrial,and agricultural runoff(Megateli et al.2009).Heavy metal contami-nation in environment can be cost-effectively removed by phytoremediation.Such a technology is most suit-able for developing countries(Ghosh and Singh2005). Generally,heavy metal cannot degrade or decompose as other contaminants;therefore,their removal by phytoremediation mainly depends on phytoextraction mechanism.In recent years,there were many?ndings reported on the removal of heavy metals by duckweed phytoremediation.
Khellaf and Zerdaoui(2009)addressed that the duckweed Lemna gibba L.can be successfully employed to remove Zn from contaminated water by 61–71%.Another research found that the duckweed L.gibba could remove Zn and Cu rapidly in the?rst 2days with concentration reduction higher than60% and then slowly in the following8days with reduc-tion of10–20%;however,the removal of Cd was linear and determined by initial Cd concentration and the removal was about90%after6or8days with initial concentrations of0.1or0.001mgL–1(Megateli et al. 2009).Duckweed phytoremediation has its limitation in heavy metal removal due to heavy metal’s toxicity. Hou et al.(2007)stated that Cd2+was more toxic than Cu2+for the duckweed L.minor;the tolerance levels of Cd and Cu were smaller than0.5and10mgL–1, respectively,and L.minor was recommended to phy-toremediate low-level contaminated waterbody by Cu and Cd.
S.polyrhiza was found to have a large capability for the uptake and accumulation of heavy metals,surpass-ing that of algae and other angiosperms.For example,
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the zinc concentration in frond tissue was2,700times higher than that of its medium(Sharma and Gaur 1995).Under experimental conditions L.minor proved to be a good accumulator of cadmium and copper and a moderately good accumulator of chromium. Duckweed can accumulate other toxic elements such as selenium(Ornes et al.1991),technetium(Hattink 2000),lead(Jain et al.1990,Kruatrachue et al.2002), uranium,and arsenic(Mkandawire et al.2004).The growth rates and ease of harvest make duckweed species useful for phytoremediation of certain heavy elements as compared to many algal species that require much more extensive harvesting equipment (Zayed et al.1998).Duckweed can therefore prove useful in treating ef?uents from mining operations. However,heavy metal concentrations can depress duckweed growth reducing its effectiveness in remov-ing toxic elements from the water body in which it grows(Boniardi et al.1999).The duckweeds L.minor (Alvarado et al.2008),L.gibba(Marín and Oron2007, Sasmaz and Obek2009),and S.polyrhiza L.(Rahman et al.2007)investigated for their phytoremediation ability to remove arsenic,boron,and uranium in water; L.gibba was found to be a suitable candidate used for the treatment of water containing boron with con-centration lower than2mgL-1(Marín and Oron2007) and to accumulated arsenic(133%),uranium(122%), and boron(40%)(Sasmaz and Obek2009);L.minor had good treatment of water with arsenic lower than 0.15mgL–1(Alvarado et al.2008);Spirodela polyrhiza L.was identi?ed as a good arsenic phyto?ltrator by physico-chemical adsorption mechanism(Rahman et al.2007).
17.2.3As a Means of Removing Toxic
Organic Compounds from
Wastewater
Duckweed species can accumulate toxic organic com-pounds such as phenols,chlorinated phenols,phar-maceuticals,and surfactants.Duckweed species can do this directly or indirectly through microbiota liv-ing on frond surfaces.For example,surfactants like alkylbenzene sulfonate and alcohol ethoxylate are mineralized by duckweed microbiota(Federle et al. 1989).Duckweed can take up?uorinated agricultural chemicals(Reinhold2006)and detoxify chlorinated phenols(Barber et al.1995).The duckweed S.olig-orrhiza L.wash proven to have the ability to uptake and transform DDT and organophosphorus pesti-cides(Gao et al.2000a,b).The ability of duck-weed to perform reductive dechlorination can be used in phytoremediation of industrial wastewaters (Ensley et al.1997).Duckweed species de?nitely have the potential to contribute to natural systems of bioremediation.
17.3Duckweed’s Other Practical
Application
In addition to the application for phytoremediation of contaminated waters,duckweed has been devel-oped for other applications.Duckweed can be used as livestock food,toxicity testing,and raw material for biofuel production.
17.3.1As a Source of Livestock Feed
The value of duckweed as a source of feed for?sh and poultry has been promoted by the World Bank,espe-cially in developing countries(Skillicorn et al.1993). Research at Louisiana State University demonstrated the value of using dried duckweed fronds as a feed source for dairy cattle and poultry(Culley et al.1981). Research at Texas Tech University has shown that duckweed species have potential as a feed ingredient for cattle,sheep,and pigs(Johnson1998,Moss1999). Duckweed also has potential as a feed ingredient in?sh farming(Gaigher et al.1984).
A great deal of work has been done on the nutri-tional value(Table17.2)of species of Lemnaceae, especially Lemna,Spirodela,and Wolf?a(Rusoff et al.1980,Landesman et al.2004).Duckweed has Table17.2Chemical composition of L.gibba meal(%
dry matter)
Chemical composition Dry matter(%)
Dry matter 3.5
Crude protein41.7
Crude fat 4.4
Acid detergent?ber15.6
Non-?ber carbohydrate17.6
Ash16.2
17Plant Nutrient Phytoremediation Using Duckweed347 Table17.3Amino acid
composition of dried L.gibba
(g amino acid/100g dry L.gibba)Amino acid
g amino acid/100g dry
L.gibba Amino acid
g amino acid
per/100g dry L.
gibba
Taurine0.03Methionine0.64
Aspartic acid 3.51Isoleucine 1.66 Threonine 1.68Leucine 2.89
Serine 1.39Tyrosine 1.27 Glutamic acid 3.67Phenylalanine 1.75
Proline 1.42Histidine0.73
Glycine 1.93Ornithine0.05
Alanine 2.30Lysine 1.85 Cysteine0.44Arginine 2.14
Valine 2.12Tryptophan0.40
been fed to pigs,cattle,sheep,chickens,ducks,and ?sh and can substitute for soybean meal in animal feed rations(Robinette et al.1980,Haustein et al. 1994,Bell1998,Moss1999,Johnson1999,Leng 2004).Wolf?a arrhiza is collected for human food in Thailand and Laos and is sold at local markets in these countries(Bhanthumnavin and McGarry1971). Its amino acid composition(Tables17.3and17.4) is more like that of animal protein than plant pro-tein having a high lysine and methionine content, two amino acids normally de?cient in plant products (Dewanji1993).Finally,dried duckweed can provide vitamins,minerals,and pigments such as beta-carotene in livestock diets,reducing the need to add these compounds to rations and thus reducing the cost of producing feed.
Research was conducted at Texas Tech University to utilize duckweed species as part of a system for recy-cling cattle wastes from feedlots(Fedler and Parker 1998).Duckweed growing in a series of ponds receiv-ing wastewater from a cattle feedlot concentrated nitro-gen,phosphorus,and other elements,both purifying this wastewater and providing an ingredient for cattle feed.Since the protein content of duckweed was found to be almost as high as that of soybean meal,duckweed production provided both a means of water puri?ca-tion and a source of livestock feed as well(Allen1997, Johnson1998,Moss1999).It was found that a level of up to11%of the protein requirements for cattle could be supplied by duckweed and provide added growth bene?ts as compared to soybean meal as the protein source(Johnson1998).
Mature poultry can utilize dried duckweed as a par-tial substitute for vegetable protein such as soybean meal in cereal grain-based diets(Islam et al.1997). Duckweed used at a level of up to15%in broiler diets can represent an important alternative source of pro-tein for poultry feeds in countries where soybean or ?sh meal is unavailable(Haustein1994).When dried Lemna spp.Nex fed to crossbred meat ducks as a sub-stitute for soybean meal there was no signi?cant dif-ference in the carcass traits between treatments(Bui et al.1995).The protein from duckweed has a biological value equivalent to that of soya beans in diets formu-lated for ducklings(Nguyen et al.1997).Duckweed has a high organic matter and protein content but has a low digestibility for ducks.When duckweed was used to replace half the ration in diets for ducks resulted in a reduced feeding costs by up to half(Khanum et al. 2005).
Diets formulated for pigs can substitute duckweed for soybean meal(Leng et al.1995).Duckweed has Table17.4Essential amino acid composition of dried L.gibba
meal(g amino acid/100g dry L.gibba)
g amino acid/100g Essential amino acid dry L.gibba Leucine 2.89
Arginine 2.14
Valine 2.12
Lysine 1.85 Phenylalanine 1.75
Threonine 1.68
Isoleucine 1.66
Tyrosine 1.27
Histidine0.73
Methionine0.64
Cysteine0.44 Tryptophan0.40
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been ensiled with other feed crops such as corn or cassava leaves to produce an alternative diet for pigs raised on small farms in Vietnam and that fresh duckweed(providing5%of the diet dry mat-ter)has a stimulating effect on weight gain(Du 1998).The addition of duckweed(Spirodela sp.) to corn signi?cantly increased both the pre-ensiled and the postensiled protein content of the silage (Eversull1982).
What has not been found are articles published on the effect of incorporating duckweed meal into penaeid shrimp diets.Fresh and decomposed duck-weed(Spirodela sp.)has been used as feed for the Australian red claw cray?sh(Cherax quadricar-inatus)(Fletcher and Warburton1997).They found that decomposed Spirodela species supported cray-?sh growth as well as commercial pellets did.The abundance of carotenoids and pigments can stimu-late crustacean growth(Hertampf and Piedad-Pascual 2000).
Perhaps the most promising use of duckweed is as a feed for pond?sh such as carp and tilapia(Landesman et al.2002).Ponds for duckweed production can be located next to?sh culture ponds,eliminating the need for expensive drying to produce a dried feed.Nile tilapia and a polyculture of Chinese carps fed read-ily on fresh duckweed added to their ponds,and the nutritional requirements of tilapia appear to be met by duckweed(Saber2004).W.arrhiza L.alone sup-ported the growth of two species of Indian carp and four species of Chinese carp as well as one species of barb Puntius javanicus(Bikr.)(Naskar1986).The her-bivorous grass carp(Ctenopharyngodon idella)digests duckweed species such as Lemna and Wolf?a quite well and it could,by itself,support production of this?sh(Cassani et al.1982,Van Dyke and Sutton 1977).Duckweed has also been tested as a compo-nent in the diet of cat?sh(Robinette et al.1980), silver barb(Azim et al.2003),and tilapia(Hassan and Edwards1992;Fasakin et al.1999)where it was also able to be substituted for soybean meal.A system for combining duckweed and?sh culture was developed in Bangladesh for use by small farmers in develop-ing countries by the non-governmental organization PRISM(Skillicorn et al.1993).This system could sus-tain a dry weight production of duckweed in excess of 20–35metric tons a year,(Leng1999).Hence,duck-weed can become a competitive source of plant protein especially in tropical countries.17.3.2As an Inexpensive and Accurate
Way of Toxicity Testing
Due to its small size and ease of growth,duck-weed species make useful organisms for toxicity test-ing(Lakatos et al.1993).Duckweed species offer many advantages for the testing of toxic compounds. Duckweed fronds assimilate chemicals directly from their aquatic media into their leaf tissue,allowing for toxicant application in a controlled manner.The growth assay for toxicant assessment is rapid and can be performed without special equipment by counting leaves.Since Lemna and Spirodela are inexpensive to maintain and the fronds are small,multiple treatments are easy to do simultaneously(Greenberg et al.1992). Duckweed species have been used to test the toxicity of oils(King and Coley1985),herbicides(Nitschke et al. 1999),phenol(Barber et al.1995),and polycyclic aro-matic hydrocarbons(Huang et al.1992),among other toxicants.
A new company in Germany has devised a Lemna toxicity test that has been approved by the European Commission(Lemna Tec1999),and the use of duck-weed for toxicity testing is mentioned in Standard Methods(1995).Duckweed can be used in both static and the dynamic test procedures(Davis1981,Wang 1990,Taraldsen and Norberg-King1990).
17.3.3Miscellaneous Uses
The ease and convenience of culturing duckweed species under both natural and arti?cial lights make this species an ideal teaching tool,both at the uni-versity and at the primary school level.An example of an experiment using duckweed that can be per-formed by elementary school students was published in the Journal of Biological Education by a Japanese teacher and two research workers(Kawakami et al. 1997).Since duckweed is so quick and easy to grow, students can learn how to study concepts of exponen-tial growth,heavy metal toxicity,photosynthesis,and asexual reproduction.The effect of environmental vari-ables like light and temperature can also be studied using duckweed(Robinson1988).
An allelopathic effect of duckweed on mosquito lar-vae may have public health signi?cance.Extracts of L.minor caused signi?cant mortality in the larvae of
17Plant Nutrient Phytoremediation Using Duckweed349
Aedes aegypti L.,a known vector of human diseases such as malaria.The presence of L.minor interfered with egg oviposition by Culex pipiens pipiens L.and was lethal to C.p.pipiens larvae at the?rst instar stage (Eid et al.1992).Duckweed may provide a source of mosquito anti-larval compounds that could have commercial signi?cance.Another use for duckweed is as fertilizer.In developing countries like India and Bangladesh where fertilizer is scarce and expensive for the small farmer,duckweed collected from local ponds and wetlands can provide a cheap and effective fertil-izer for rice and other crops(Ahmad et al.1990).It also makes an excellent compost and much of the duck-weed harvested from Louisiana wastewater treatment ponds is used for this purpose.Finally a new use for duckweed biomass as a cell-structured support mate-rial has emerged as a new technology for yeast fermen-tation.W.arrhiza biomass was extracted with ethanol and loaded with yeast cells.This yeast-impregnated W. arrhiza was placed in a semicontinuous?uid-bed fer-menter for the production of beer(Richter et al.1995). New uses for duckweed species will doubtless arise as more researchers learn to appreciate the versatility and potential of Lemnaceae.
From an energy standpoint,most terrestrial plants vary from about14.8to18.4kJ/g while aquatic plants vary from10.0to21.5kJ/g.Duckweeds average about 13.5kJ/g.When you consider the production levels of the various plants,duckweeds can produce from122×106to539×106kJ/ha annually,yet the range for many species of aquatic plants considered varies from a low of12×106to a high of2,900×106 kJ/ha annually(Fedler et al.2007).Table17.5shows the production level of duckweeds at various locations around the world.17.4Summary
Duckweeds of the family Lemnaceae are small,?oat-ing,aquatic plants with a worldwide distribution.They are one of the fastest growing angiosperms and can double their biomass within2days under optimal con-ditions.They have a high protein content(10–40% protein on a dry weight basis)although the moisture content(95%)of fresh duckweed biomass is quite high as well.Potentially,members of the Lemnaceae(of the genera Lemna,Spirodela,and Wolf?a)can produce edible protein six to ten times as fast as an equiva-lent area planted with soybeans.Therefore species of Lemnaceae potentially have a great value in agricul-ture.
A great deal of work has been done on the nutritional value of species of Lemnaceae,especially Lemna,Spirodela,and Wolf?a.Duckweed has been fed to pigs,cattle,sheep,chickens,ducks,and?sh and can substitute for soybean meal in animal feed rations.Its amino acid composition is similar to that of other plant proteins except for having a higher lysine and methionine content,two amino acids normally de?cient in plant products.Finally,dried duckweed can provide vitamins,minerals,and pigments,such as beta-carotene in livestock diets,reducing the need to add these compounds to rations and thus saving the producer money while having a higher quality feed as compared to the normal basal diet usually fed.
Much research has been done on the use of duck-weed in wastewater treatment systems.As part of a facultative treatment system,duckweed can cover treatment ponds and reduce the growth of algae in these ponds as well as reduce nitrogen in the ef?uent
Table17.5Annual worldwide duckweed growth rates(Leng et al.1995)
Location Yield(tons/acre)Yield(metric ton/ha)Source
Thailand 4.5–4.910–11Hassan and Edwards(1992),
Landolt and Kandeler(1987) Israel5–810–17Porath et al.(1979)
Russia 3.1–3.67–8Landolt and Kandeler(1987) Uzbekistan3–77–15Landolt and Kandeler(1987) Germany7–1016–22Landolt and Kandeler(1987) India1022Landolt and Kandeler(1987) Egypt510Landolt and Kandeler(1987) Louisiana1–102–23Culley and Epps(1973),
Rusoff et al.(1980),
12–3527–79Mestayer et al.(1984)
Israel16–2336–51Oron et al.(1984)
https://www.doczj.com/doc/1018746318.html,ndesman et al.
from these ponds through nitrogen uptake and denitri-?cation.Duckweed can also be a part of constructed wetland systems,either as a component of a wetland receiving wastewater or as plants that polish nutrients from wetland-treated ef?uents.
Due to their small size and ease of growth,duck-weed species make ideal organisms for toxicity testing.
A new company in Germany has devised a Lemna toxicity test that has been approved by the European Commission,and the use of duckweed for toxicity testing is mentioned in Standard Methods.Duckweed can be used in both the static and the dynamic test procedures.
Duckweed plays an important role in the ecology of wetland environments by providing a substrate for the growth of diatoms,protozoa,and bacteria.This phyl-losphere(microorganisms living on the outer frond surface)in turn supports insect life as well as enhanc-ing the nutritive value of duckweed for waterfowl and wetland animals such as nutria and turtles.In addition cyanophytes residing in the phyllosphere of duck-weed fronds can?x atmospheric nitrogen,providing nitrogen input in oligotrophic aquatic environments.
The three dominant duckweed genera(Lemna, Wolf?a,and Spirodela)will all grow on organic(for example,wastewater)as well as an inorganic media (for example,Hoagland’s medium).All three species grow faster on organic as opposed to inorganic media with equivalent amounts of nitrogen and phosphorus. This may be due to the ability of duckweed species to take up organic molecules directly from the media in which they grow.Even inorganic media supplemented with glucose will support faster duckweed growth than media without glucose.
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个人公司章程 公司章程 一、总则 第一条依据《中华人民共和国公司法》、《中华人民共和国公司登记管理条例》及有关法律、法规的规定，制定本公司章程。本公司章程对公司股东、董事、监事、经理均具有约束力。 第二条公司经公司登记机关核准登记并领取法人营业执照后即告成立。 二、公司名称和住所 第三条公司名称：有限公司。(以预先核准登记的名称为准) 第四条公司住所：市(县镇)路(街)号。 三、公司的经营范围 第五条公司的经营范围：(含经营方式)。 四、公司注册资本 第六条公司的注册资本为全体股东实缴的出资总额，人民币万元。(要符合法定的注册资本的最低限额) 第七条公司注册资本的增加或减少必须经股东会代表2/3以上表决权股东一致通过，增加或减少的比例、幅度必须符合国家有关法律、法规的规定，而且不应影响公司的存在。 五、公司股东名称
第八条凡持有本公司出具的认缴出资证明的为本公司股东，股东是法人的，由该法人的法定代表人或法人的代理人代表法人行使股东权利。 第九条公司在册股东共人，全部是法人股东 股东名录： (一)法人股东： 1.法人名称： 住所： 法定代表人： 认缴出资额：万元，占公司注册资本的 % 出资方式： (货币或实物或其它) 认缴时间：年月日 2.…………………………………… 第十条公司置备股东名册，并记载下列事项： (一)股东的姓名或者名称及住所; (二)股东的出资额; (三)出资证明书编号。 六、股东的权利和义务 第十一条公司股东享有以下权利： 1.出席股东会，按出资比例行使表决权;
2.按出资比例分取公司红利; 3.有权查询公司章程、股东会会议记录、财务会计报表; 4.公司新增资本时，可优先认缴出资; 5.按规定转让出资; 6.其它股东转让出资，在同等条件下，有优先购买权; 7.有权在公司解散清算时按出资比例分配剩余财产; 第十二条公司股东承担以下义务： 1.遵守公司章程; 2.按期缴足认购的出资; 3.以其出资额为限对公司承担责任; 4.出资额只能按规定转让，不得退资; 5.有责任保护公司的合法权益，不得参与危害公司利益的活动; 6.在公司登记后，不得抽回出资; 7.在公司成立后，发现作为出资的实物、工业产权、非专利技术、土地使用权的实际价额显著低于公司章程所定价额的，应当由交付该出资的股东补交其差额，公司设立时的其他股东对其承担连带责任 七、股东(出资人)的出资方式和出资额 第十三条出资人以货币认缴出资额。(以实物、工业产权、
企业先进个人事迹 【总厂之星·铿锵玫瑰】记xxx单位xxx同志 勇于开始才能找到成功的路 --记xxx单位xxx同志 xxx单位xxx xxx，一名默默奉献于总厂数字化业务的技术尖兵。2006年研究生毕业后xxx来到xxxxxx 工作，曾先后在抽油机制造分厂、产品研发中心从事技术研发。自总厂业务转型开始，她又积极投身其中，凭着自己勤于学习、善于钻研、勇于实践的性格，用短短三年时间，在数字化新产品、新技术开发应用方面结出了丰硕成果，成为xxxxxx数字化业务转型的铺路石，数字化技术创新的火炬手，数字化技术应用的传道者，数字化抽油机推广的护航人。 冲锋一线数字化业务转型的铺路石 2009年，xxxxxx按照xxxxxx要求制定了以数字化为核心推进业务转型的发展思路，并从全厂抽调了二十名技术人员探索涉入这一全新的业务领域。xxx是这二十名技术人员里唯一的女性，但作为总厂唯一的自动化专业的研究生，她又必须承担为总厂数字化业务转型闯出一条新路的重托，她没有犹豫，毅然放弃了研发中心优裕的办公环境和新婚不久的家庭，同其他男同志一道上前线学习、钻研数字化新技术，她充分运用专业所长，在团队里交流学习心得，帮促了其他技术人员的迅速成长，也自然而然地成为了这支技术团队的核心和带头人。现场施工时，她又与男同志一道爬电杆、装设备、接线、调试，亲力亲为、奋战一线，直到一天在去井场的颠簸道路上，她蜷缩在车后排的一角，脸上的汗珠直往下掉，才被大家送往医院检查，原来她早有身孕，大家都埋怨她不该隐瞒情况，她只歉意地解释现在是施工的关键期她不想离开。 刻苦钻研数字化技术创新的火炬手 根据xxxxxx "数字化关键技术要为xxx自己掌握"的指示精神，xxxxxx成立了专门的数字化产品研发团队，xxx同志以扎实的专业功底和实践能力成为了这支研发团队的副组长。按照"立足自主研发，技术研发与技术引进相结合"的原则，她带领研发组一边收集资料，学习国内外成熟的数字化技术与经验，一边拖着日渐笨重的身体，跑高校、院所和专业公司，谈技术引进与合作，顺利签署了多项合作协议。同时，她和团队也完成了 "数字化采油系统故障检测与现场维护系统开发"等8项xxxxxx和总厂重点科研项目，先后获得xxxxxx科学技术进步奖一等奖和二等奖各一项，"从式井场套管自动加药装置"等四项技术获得的股份公司实用新型专利授权，2010年她所在团队又荣获总厂"建功立业"先进集体称号，她也荣获女职工"建功立业"先进个人称号。 无私奉献数字化技术应用的传道者 通过刻苦钻研学习，xxx同志掌握了扎实的数字化技术功底，但她追求的不是一支独秀，而是满园芬芳。在xxxxxx数字化业务纵深推进过程中，她在人员培训以及数字化新技术、新产品现场推广应用方面倾注了大量心血。2011年，xxxxxx数字化技术服务在油田范围内全面铺开，因为服务大队是整建制转型， 前线人员的技术水平参差不齐，关于各种技术问题的求助电话铺天盖地打到技术研发团队。一方面，xxx耐心地对各种问题给予解答或远程技术指导，另一方面，她迅速组织技术团队编写了《数字化井站维护服务操作指南》，按照实际操作程序和步骤重点介绍了井场油系统、阀组间、视频监控系统等不同厂家和型号设备的配置、调试方法，为现场维护服务工作的顺利开展提供了强有力的技术支撑和保证。 勇挑重担数字化抽油机推广的护航人 第二代数字化抽油机在油田大范围推广应用，xxx作为数字化抽油机控制系统子项目的负责人，她主动承担了该项核心技术的现场技术支持工作，起草编制了《第二代数字化抽油
交通事故三维模拟演示系统 产品简介 交通事故三维模拟演示系统集成了三维360度全景照相技术、三维虚拟现实动态仿真技术（增强现实技术）为一体，完全满足现在公安系统里现场全景照相、全景三维测量、三维重建、模拟、和分析的应用。是北京金视和科技有限公司集十几年来图形图像和三维仿真领域的尖端科研成果，并结合多年来对公安交通系统的调研数据进行定制化开发的解决方案。 交通事故三维模拟演示系统生成高度逼真的三维场景图片和动画片。把这些全景图片、三维场景、动画片和声音、文字结合，为侦查、技术、指挥人员生成各种三维虚拟案件现场场景的多媒体影音和影像材料。对这些数字化多媒体信息进行分析、演示，并可以在网络服务器上发布、保存、修改案例，其他用户可以通过网络服务器进行查询、观看案例。为案件的侦破、记录、汇报、存档查询，都提供了便利的直观方便。 交通事故三维模拟演示系统是由三维数字化图形软件和360°全自动机器 人拍摄系统组成。是基于图形图像和三维仿真领域的尖端科研成果，并结合多年来对交通事故处理部门的调研数据进行定制化开发的解决方案。 产品特点 交通事故三维模拟演示系统搭载的全景拍摄系统，由高端单反数码相机、精密鱼眼镜头和全自动拍摄云台组成，可以在一分钟内拍摄一组完整的现场全景图片，并以全自动方式进行拼接融合，无须人工干预拼接过程。达到交通事故现场快速全景重建的目的。 在传统的工作流程当中，由于人为、天气等外界因素干扰，事故现场很容易在短时间内遭到破坏和干扰。鉴于事故现场的特殊性，快速、完整、准确的保存事故现场，交通事故现场不可能像刑事案件现场那样长时间保留。交警在记录事故现场时，大多是通过昂贵的单反数码相机，直观的对事故现场进行大量的物证和场景拍摄，在后期分析事故现场时由于照片数量繁多，很难建立起事故现场的形象认知，甚至有可能会漏拍一些关键信息。借助360°全自动机器人拍摄系统将真实交通事故现场的完整的保存下来，可以在撤离交通事故现场后随时在交通事故现场全景图上进行截图、测量和分析。 现场采集物证图像及多场景热点添加在真实的交通事故现场中需要拍摄大量的现场细节图像(车辆痕迹、道路痕迹、现场环境、尸体、现场散落物和遗留物、血迹等)。但大量的现场图片容易让技术人员混淆物证，这对于日后的案情分析来说有重大影响。交通事故三维模拟演示系统的热点添加功能可以将所有采集到的现场细节图像以超级链接方式添加到现场全景图和三维重建现场中，并且可以用鼠标双击放大凸显细节图像，还可以创建文件夹对物证图像进行组织分类、可重命名以及删改细目照片资源，为事故过程分析带来极大的帮助。
深圳市大诠实业有限公司简介 深圳市大诠实业有限公司大诠旗下网络变压器厂于2007年6月成立，公司主要生产脉冲变压器、滤波器、磁环线圈等磁性元件。2016年注册属于大诠实业的自主网络滤波器品牌NMS.工厂面积5000多平方米，前期项目总投资三百多万元人民币，目前年产值达6000多万元人民币。 公司属于内资企业，总部设于深圳市龙华新区大浪街道，现有员工300人左右。其中一些工厂在云南文山市环城西路中部，下辖13个分厂约7000人。大诠实业东莞工厂位于广东省东莞市高埗镇芦溪村银涌工业区创鸿基工业园四楼。公司目前正处于高速发展时期，是同行客户信得过的企业。 大诠优势 所有产品均符合全球业界各项质量及环保规定。公司拥有一个经验丰富的管理团队，有一批爱岗敬业，开拓进取，团结一心，坦诚从事之优秀员工，有公正严明的规章制度及相对完善的管控体系。 公司经过多年的锤炼，积累了丰富的集生产加工，开发，品质，后勤保障等各种管控经验，有多渠道固定之客户群，客户遍布珠三角，长三角以及欧美，东南亚等发达国家和地区。也有永久持续，品质交期稳定之产品前段供应链。 大诠文化 愿景：成为全球网络变压器最具领导地位的生产商！ 使命：为网络通讯行业提供最具竞争力的多元化网络变压器！ 理念：与员工共成长，与客户求共赢！以质量创品牌，以诚信谋发展！ 精神：开拓、创新，立足市场求发展；优质、高效，专心服务为用户! 价值观：以人为本，客户至上，诚信经营，大家共赢！ 工作作风：产前准备严格核对；生产过程严格要求； 员工作业严格规范；出厂成品严格把关。 服务宗旨：每位客户的满意是环宇人存在价值的最好体现！ 大诠产能（300K/天） 12PIN（超薄）SMD 20K/天 16PIN （常规）SMD 50K/天 24PIN（小）SMD 60K/天 24PIN（大）SMD 20K/天 48PIN（常规）SMD 10K/天 18PIN（单排常规）DIP 5K/天 36PIN（单排常规）DIP 10K/天 24PIN（双排常规）DIP 10K/天 48PIN（双排常规）DIP 15K/天 设备仪器列表 序号设备名称数量用途序号设备名称数量用途 1 TCP 1 集高压测试、综合测试、外 观检验、包装于一体的设 备。 14 切脚机 6 DIP产品切脚设备 2 射频网络分 析仪 1 产品特性测试15 显微镜8 产品局部放大，用于分析产品异 常。
个人开公司必备：注册、税务 一、选择公司的形式：- 普通的有限责任公司，最低注册资金3万元，需要2个（或以上）股东，从06年1月起新的公司法规定，允许1个股东注册有限责任公司，这种特殊的有限责任公司又称“一人有限公司”（但公司名称中不会有“一人”字样，执照上会注明“自然人独资”），最低注册资金10万元。-- 如果你和朋友、家人合伙投资创业，可选择普通的有限公司，最低注册资金3万元；如果只有你一个人作为股东，则选择一人有限公司，最低注册资金10万元。- 二、注册公司的步骤：- 1.核名：到工商局去领取一张“企业（字号）名称预先核准申请表”，填写你准备取的公司名称，由工商局上网（工商局内部网）检索是否有重名，如果没有重名，就可以使用这个名称，就会核发一张“企业（字号）名称预先核准通知书”。这一步的手续费是30元。（30元可以帮你检索5个名字，很多名字重复，所以一般常见的名字就不用试了，免得花冤枉钱） 2.租房：去专门的写字楼租一间办公室，如果你自己有厂房或者办公室也可以，有的地方不允许在居民楼里办公。租房后要签订租房合同，并让房东提供房产证的复印件。- 签订好租房合同后，还要到税务局去买印花税，按年租金的千分之一的税率购买，例如你的每年房租是1万元，那就要买10元钱的印花税，贴在房租合同的首页，后面凡是需要用到房租合同的地方，都需要是贴了印花税的合同复印件。-- 3.编写“公司章程”：可以在工商局网站下载“公司章程”的样本，修改一下就可以了。章程的最后由所有股东签名。- 4.刻私章：去街上刻章的地方刻一个私章，给他们讲刻法人私章（方形的）。费用大概20元左右。-
5.到会计师事务所领取“银行询征函”：联系一家会计师事务所，领取一张“银行询征函”（必须是原件，会计师事务所盖鲜章）。如果你不清楚，可以看报纸上的分类广告，有很多会计师事务所的广告。-- 6.去银行开立公司验资户：所有股东带上自己入股的那一部分钱到银行，带上公司章程、工商局发的核名通知、法人代表的私章、身份证、用于验资的钱、空白询征函表格，到银行去开立公司帐户，你要告诉银行是开验资户。开立好公司帐户后，各个股东按自己出资额向公司帐户中存入相应的钱。- 银行会发给每个股东缴款单、并在询征函上盖银行的章。- 注意：公司法规定，注册公司时，投资人（股东）必须缴纳足额的资本，可以以贷币形式（也就是人民币）出资，也可以以实物（如汽车）、房产、知识产权等出资。到银行办的只是货币出资这一部分，如果你有实物、房产等作为出资的，需要到会计师事务所鉴定其价值后再以其实际价值出资，比较麻烦，因此建议你直接拿钱来出资，公司法不管你用什么手段拿的钱，自己的也好、借的也好，只要如数缴足出资款即可。- 7.办理验资报告：拿着银行出具的股东缴款单、银行盖章后的询征函，以及公司章程、核名通知、房租合同、房产证复印件，到会计师事务所办理验资报告。一般费用500元左右（50万以下注册资金）。- 8.注册公司：到工商局领取公司设立登记的各种表格，包括设立登记申请表、股东（发起人）名单、董事经理监理情况、法人代表登记表、指定代表或委托代理人登记表。填好后，连同核名通知、公司章程、房租合同、房产证复印件、验资报告一起交给工商局。大概3个工作日后可领取执照。此项费用约300元左右。- 9.凭营业执照，到公安局指定的刻章社，去刻公章、财务章。后面步骤中，均需要用到公章或财务章。--
公司先进岗位事迹材料 锐意创新，建立行业领先的销售管理平台 ××集团公司销售部经理××自××年加入本公司以来，在领导的关心、支持和同事的配合下，比较圆满地完成了自己所承担的各项工作任务，在政治思想觉悟和业务工作能力等方面都取得了较大的进步，为今后的工作和学习打下了良好的基础。爱思范文23: 该同志政治立场坚定，遵纪守法；工作勤奋敬业，积极进取，团结协作，恪守职业道德，遵守社会公德；求真务实，作风严谨，诚实守信，具有良好的学术道德。 该同志在工作中勤于学习，具有扎实的专业理论基础，致力创新。经过销售部市场主管岗位及目前销售部经理岗位上五年多的工作，通过不断学习、不断积累，该同志具备了比较丰富的工作经验，能够比较从容地处理日常工作中出现的各类问题，在组织管理能力、综合分析能力、协调办事能力和文字言语表达能力等方面，都有了很大的提高，不但保证了本岗位各项工作的正常运行，而且能够较好地把握业务发展方向，结合业务工作提出新办法，建立健全销售管理平台和管理体系，极大的提高了本公司销售管理水平，使公司的销售管理在制药行业中保持领先。 一、建立crm系统，实现销售管理网络化、信息化、制度化。在以往传统的销售管理体系中，普遍存在销售过程难以监控、人员行为难以控制、经销商行为无法监管、销售费用难以控制、销售决策因无准确的市场信息所造成的主观失误等问题。针对以上的问题，该同志根据管理学的进步和信息发展的趋势，在公司领导的支持和同事的配合下，建立了利用现代信息与网络技术，将互联网与集团局域网融为一体的crm销售管理系统。crm销售管理系统的核心工作是围绕公司的市场、销售人员、经销商通过有效的方式准确地反映销售人员的工作状况，销售费用的发生状况，产品的销售状况及市场信息的变化状况等动态的销售信息。整个销售管理系统的监控考核的核心是市场和销售人员。在这些准确的销售动态信息的基础之上形成相关的统计分析数据，既是对市场及销售人员进行考核的量化指标又是提供给销售决策者重要的基本参照物。依托该系统，本公司以消费者满意为核心，建立起消费者→药店→二级经销商→一级经销商→集团总部的商业网络，并在此基础上建立起业务员、医务人员网络，从药店到患者，建立起家庭健康档案，履行家庭医师的职责，服务于患者。crm系统通过现代化的手段，解决了一系列销售管理的难题，为公司销售费用的控制及销售业绩的大幅提升做出了贡献，极大地提高了企业的营销运行效率，大大降低了企业的经营成本。
个人注册公司应该选择哪种类型的个人注册公司应该选择哪种类型的，对于初次创业的人来说，在资金、社会关系、业务渠道、经营实力等方面处于弱势，初次创业的人要经过详细的了解和计算来选择公司的组织形式，尽量选择最适合自己的公司形式注册。下面雁荡上海注册公司，对适合个人注册的几个类型进行了简要介绍和优劣对比分析。一、个人独资企业 个人独资企业是指由一个自然人投资,财产为投资者个人所有,并以其个人财产对企业债务承担无限责任的经营实体。 （一）个人独资企业其优势主要体现在: 1、设立门槛低。没有法定最低注册资本金的要求,投资人只需有申报的出资即可。 2、企业自由度大,经营管理灵活。个人独资企业财产归投资人所有,由投资人支配;投资人可以自行管理,也可以选择聘任管理或委托管理。 3、企业负税轻。个人独资企业非企业所得税纳税主体,企业所得不必缴纳企业所得税,投资人只须就个人投资所得交纳个人所得税。 （二）个人独资企业其劣势主要体现在： 个人独资企业作为非法人企业,不能以自己的财产独立承担有限责任,所以个人独资企业一旦资不抵债,投资人应以自己的全部财产偿还企业不能偿还的债务,承担的风险较大。 二、一人有限责任公司 一人有限责任公司简称一人公司，它是由一个自然人或者法人投资设立的有限责任公司。相对于个人独资企业而言，尽管投资人都是一人，但二者却存在根本的不同。一人公司是法人企业，有自己独立支配的法人财产，公司财产与投资人的个人财产严格分开，投资人以认缴的出资为限对公司承担责任，公司以自己所有的财产对债权人承担有限责任。 （一）一人公司的劣势主要体现在： 1、一人公司设立门槛比较高;公司法规定，注册一人公司，最低资本限额十万元人民币，而且必须一次缴足。 2、投资人负税较重。公司必须就其所得缴纳企业所得税，投资人从公司取
个人与企业的关系 企业发展离不开各个方面的发展，但就个人发展与企业发展的关系而言，从某种角度来说，可以理解为鱼和水的关系。鱼儿离不开水，也就是说个人的发展离不开企业这个大舞台；水深则鱼悦，表明企业发展良好，就会给个人发展提供相对较好的条件，个人从中受益匪浅！在现实社会中，我们每个人要给自己定好位，为企业的良好发展贡献自己的一份力量。 只有在集体中,个人才能获得全面发展其才能的手段,也就是说,只有在集体发展的前提下，个人才有可能发展 集体的氛围和风格在无形中会影响到每一个人，举一个最简单的例子，就是大学的文化和历史沉淀，人们常说在北大呆两年，什么也不干，熏也给你熏出点北大的气质来；还有“近朱者赤，近墨者黑”，其实都是这个道理。 其实，说的这些很多人都是认同的，并且在意识里是存在的，但是往往却有这样的一个误区，总希望自己成长在一个优秀的集体中，却从没有考虑怎样去营造一个优秀的集体，怎样去领导一个集体，或者当面对一个集体的困难时，不愿意去承担责任。当然，这中间可能有自身性格、能力、取向等各方面的原因，但是我想从根本上来讲还是没有把集体的利益真正融入到个人发展当中去，还是没有正确的团队观念。 那什么是正确的团队观念呢？每个人的看法都可能不同，但我想至少两个方面，一是主观欲望上渴望在一个优秀的集体中，并愿意配合集体的各项活动，愿意为集体的成长进步尽一个成员的义务，希望集体的发展促进自己的成长与进步；二是愿意承担集体的责任，以集体的发展为己任，以集体成员的成长进步为己任，尽自己最大的努力促进集体的发展。其实这两个方面说简单一点就是成员意识和主人翁意识，但二者却有着本质的区别，应该是两个层次上的。 我想大学时代，最重要的集体就是班级，大多数同学对班级都是有感情的，但往往都是停留在第一层次上，都渴望自己的班级团结、向上、相亲相爱，但很少有同学主动的去营造这种氛围。其实班长和普通同学在班级建设过程中的角色定位的差别就在这里。很多同学不愿意做班长也是因为这个，不愿意去承受这种压力。 但我想，任何一个团队，任何一个集体中，如果成员只是具有第一个层次的团队观念的话，这个团队不会取得多么大的成功，这个团队的成员也不会有什么大的发展；而如果每一个人都把自己当着团队真正的主人，都在谋划团队的发展，我想团队就会越来越好，成员同样就会越来越好，这就会形成一个良性的循环。 集体的发展是每一成员都应该思考的事情，每一个人都会从集体中获得东西，有形的或无形，如果你
公司先进人员事迹材料 年3月，我来到华茂工作，成为华茂科教仪器公司的一般职员。工作中，憨厚、朴实的我一方面积极向老职员虚心请教，一方面利用歇息间隙对产品进行熟悉、组装、维修，将自己的满腔热情彻底投入到了工作之中。艰难的努力，务实的工作，很快使我成了公司的业务骨干。“一具人能够没有文凭，但决别能够没有知识”，这是我十分观赏的一句话，为此，我几乎把所有的业余时刻都用在了钻研业务上，努力将自己的工作吃透，干好。 随着公司业务的拓展，工作难度也在加大，因公司业务人员少，一人身兼多职，我的要紧工作是代表公司出去招投标、整理投标样品。在整理样品的过程中，严格把关，因为样品在投标过程中占的比重较大，会直接妨碍到投标的结果。有时候遇到提供样品数量多的事情时，就必须花上好几天的功夫，而且在整理的过程中会遇到不少的难题，这就需要和相关技术人员进行交流，争取满脚客户的技术要求。 记得去山东菏泽投标时，我们公司共投了七标段，每个标段七本标书，做好的标书有三箱，再加上样品七箱，由于投标时刻紧迫，也为了安全期间，只能标书随身带，我一人拖着沉重的标书和样品，到了中途的徐州转车时，差不多是疲乏别堪，一想到时刻紧，任务重，也别可有半点怠慢，到了菏泽之后，算是紧继续摆放样品，等摆好之后，差不多是晚上十点多了，固然如此投标的次数有不少次，可是我没有一次怨言，时间把公司的利益放在第一位，个人的得失放之后。 这二年，随着公司业务拓展。公司经过代理商，业务涉及的省份较多，有等地，出差的频率别断的增加。有的时候刚回到家两天，就收到公司的委派任务。由于是和教育部门打交道，因此效率是特别重要的，我别得别放弃歇息时刻，为了能在第一时刻见到客户，经常是周六、周日的时刻在路上赶，让我经历犹新的是，11月份处理的业务。差不多延续一具月没有歇息了，体力严峻超支，那时候公司组织的旅游也别得别放弃。 去送，送货过程中每天早上6点起床，到别处零下10度的天气中进行分货、配送、装车等，有好几天吃饭也是有一顿没一顿的，晚上普通基本上八点左右回到仓库，和同事按照客户的意愿商讨下一步的打算，并要思考为公司减少别必要的开支，经过十三天时刻的配送，按合同要求顺利完成天津400多所所学校的配送工作，确保客户中意，让客户早日验收汇款。在出去招投标或送货时，我牢记，我是代表华茂的，我时时间刻注意自己的言行，维护公司的形象，以热忱的工作态度投入到工作中去。 很荣幸被公司推举为2011年度的优秀职员，这既是公司对我个人工作能力的确信，也是对我做好将来工作的一种鼓舞，尽管这一年里我没有什么可炫耀的业绩，但在自己的工作岗位上始终兢兢业业，仔细对待每一件事，多考虑，多关注，为把好产品的质量关尽自己的一份力。在将来的工作中，我将更加出色的完成各项工作，别辜负公司对我期望。
壹玖公司简介 河南壹玖实业有限公司成立于2014年7月的，壹玖实业是一家融实体企业经营与商业培训为一体的民营企业，由董事长袁国顺先生创立的“免费商业模式”培训为切入点的，企业家智慧及资源密集体。 壹玖实业是河南唯一一家以企业发展落地为基础，从商业模式学习切入、实操落地的新经济生态大系统，致力于中小企业未来根本核心竞争力的研究，通过帮助企业商业模式升级带动企业稳定，飞速发展，在行业里脱颖而出。 壹玖实业以河南为中心向全国乃至世界辐射，截止2016年底已在全国发展100家事业部，力争三年内发展1000家，目前已拥有中小企业家会员1万多人。挽救濒临倒闭民营中小企业120家以上，盘活10亿以上烂尾楼项目15个。间接帮助社会多创造10万个以上就业机会。河南壹玖实业有限公司目前正致力于帮助会员企业打造更具竞争力的免费商业模式，以振兴民族经济为己任，用免费模式，让奇迹发生，助推中华民族伟大复兴的中国梦早日实现。 公司自成立至2016年年底，已拥有高素质员工500多人，参股、控股多家公司及项目，初步形成了以中原为核心，辐射全国的战略布局。直接影响到的企业家会员超过1万名，间接影响到的企业超过8万余家。 壹玖实业以袁国顺老师为核心的企业家领导团队，用自身经营企业20多年的经验帮助会员企业。壹玖系统可以彻底帮助您解决现在面临的企业问题，为您的企业装上更具竞争力的武器，更轻松的经营企业。壹玖资本，等您加入！
袁国顺，河南壹玖实业集团董事长，一个实实在在践行免费模式的企业家！ l38O年25月6日9622 分電联年月日分，找袁国顺老师。“企业的一切问题都是老板的问题，老板行，一切都行!”“企业家不是努力不够，而是思维不够。” 袁国顺先生搏击商海二十年，运用哲学、逻辑学和心理学，从自己和他人成功或失败中剖析深层次的原理，形成了独特新颖而且具有现实指导意义的新的商业思维模式。“一花独放不是春，百花盛开春满园”。为了帮助哪些和他一样在商海中打拼的企业家少走弯路，袁国顺先生走上讲台，帮助多家企业创造了行业神话和奇迹。 壹玖资本自助式大平台主办的“聚世界资本、创商海经济”广东峰会上，国内顶级讲师、河南壹玖实业有限公司董事长袁国顺出场便语出惊人。他指出，在竞争激烈的当下，免费模式可以帮助企业实现腾飞。“中国企业家普遍认为免费就是无常付出、倒贴，其实这只是表象。根据企业产品特性，设定一个免费的时间段做铺垫，调试时间的浓度来让客户形成惯性消费行为，最终变成你的企业的忠实客户。” 纵观整个社会经济发展，50年前，开工厂能盈利，30年前做贸易很赚钱，现在互联网如此发达、产品库存极其庞大的情况下，很多企业家必须遵循当下互联网经济的规律——平台分享、合作共赢。如果企业家还停留在“机制、约定、管理员工、经营方法”的层面，企业是很难发展的，这也是为什么传统企业最近几年举步维艰的原因，当然这不是企业家的过错，也不是社会的过错，而是整个经济的发展到了新的周期。 袁国顺在接受采访时表示：请广大企业家不要认为免费就是打劫、白送，而是根据你的企业产品特性，设定一个免费的时间段做铺垫，调试时间的浓度来让客户形成惯性消费行为，最终变成你的企业的忠实客户。 来自全国各地近600个企业家参加峰会连续三天的“顶尖免费商业模式”学习。其中不乏广东商业巨头，如广药集团高管、喜喜传媒、国龙集团高管等。在为期三天的峰会中，还举办了壹玖资本广东分公司的启动仪式。广东壹玖资本负责人汪先付在接受采访时表示，“我们实战峰会灌输的是一种商业模式：弱化员工能力，强化模式的价值。”而公司的互助经济大平台不是简单的企业家培训、关系的抱团，而是默契的利益共同体。 平台里的企业家必须有共同的理念和价值观，“免费模式”只是系统里的一环，它要实现的并不是真正的免费，而是通过免费来延伸利润链条。
个人公司月总结 篇一：一个月工作总结 工作总结 我自XX年4月8日正式上岗至今已过去了足足一个月的时间，在过去的一个月里，我不断学习，不断成长，下面对这一个月的工作进行初步总结： 一、万事开头难。从一开始就要有心，有心才能办好事。俗话说万事开头难，一切事情都要有个很好的开头，工作自然如此，在来公司之前我就已做好充分的心理准备，无论工作是怎样的我都要认真对待，细心完成。工作重，要不气不馁不抱怨，工作轻，要不骄不躁足耐心。只有好心态，才有工作的好心情，进而才有好效率。 二、谦虚使人进步。生活是个大讲台，许多东西都要虚心受教。在学校学做人，在社会学做事。生活处处有学习。工作自然也是如此，刚来时，我被指派跟着阿姨尝试、学习。在此期间，我越来越懂得谦逊，谦虚使人进步，骄傲使人落后。世界之大，有许多东西是我所不知道的，我只有谦逊，不断学习，不断充实自己，才能有一个更好的自己。 三、众人拾柴火焰高。一定要与人合作，才能快速高效。自古就有圣人言：众人拾柴火焰高。在工作中，与人合作必
不可少，不仅要能合作，还要会合作。在生产部呆的这一个月让我充分认识到了这一点。无论是大家一起倒花还是好几个人一起换盆，我们自然而然会分工合作，几人搬，几人装，几人跟车，合作无间，效率自然高。 四、责任重于泰山。一定要有责任心，事情才能做到位。 爱因斯坦说过：对一个人来说，所期望的不是别的，而仅仅是他能全力以赴和献身于一种美好事业。而一个人要对一件事全力以赴，那他必须要有责任心，心中有责，做事才能负责，才能竭尽全力。而只要做事者竭尽全力，再难的事情也有解决的办法，世上无难事只怕有心人嘛。在我看来生产部是公司的源头，更要做好，管窖人员更要有责任感，才能更好的为公司为自己创造利益。 综上所述，我对接下来的工作做一个初步规划： 首先，我将每天以一个好心态来面对我的工作。将生活情绪撤离工作，不能让私人情绪影响工作。其次，在学习生活中，不骄傲不自满，随时学习，随时充实自己。以一个谦逊的自己面对以后的工作学习。再次，我要做到更好的与人合作，无论是生产部还是行政部都少不了分工合作，在合作中与人形成更好的合作默契，追求更高的效率。最后，在任何时候，做任何事，都要全心全力，认真负责。无论是谁交代的任务、工作，不接则已，接了就要全心全责。以整个心
模拟演练与3D培训系统方案 煤科集团沈阳研究院有限公司 2014/2/28
一、模拟演练技术资料 DMX-135A仿真模拟与演练评价系统说明 1.系统型号 DMX-135 A 通道长度 多功能模拟训练系 统 2．系统简介 “3D-VR煤矿事故仿真和安全培训 演练系统”是我院与澳大利亚新南威尔 士大学合作开发的一套应用于煤矿安全培训的大型沉浸式仿真演练系统。我院通过借助UNSW(新南威尔士大学)的世界领先技术及软硬件平台，开发出符合我国国情的煤矿安全培训模块。本系统可由危险识别、灾害模拟、自救逃生、救护救援等多个安全培训模块组成，本系统模块是按照国家煤矿安全规程和新编煤矿安全技术培训教材编制
而成。采用虚拟现实（VR）技术、360度环屏投影播放技术、12.1环绕立体声技术、3D电影技术、计算机网络协同处理技术为煤矿工人安全和技能培训提供一流的“沉浸式”培训环境，将安全培训装备和质量提升到一个崭新的水平。 通过使用本系统，创建一个逼真的虚拟现实世界，使学员在体验各种真实场景同时，学习各模块相关操作知识，认识灾害的发生、发展过程及危害，并通过问答式的交互学习，快速掌握每个模块的操作步骤及要点。从而提高矿工的整体技术水平、思想素质、及各种突发状况的应对能力，从而使煤矿整体操作能力及防范意识得到提高，真正进入规范化管理阶段，降低各种事故发生的概率。 DMX-135A多功能模拟训练系统通道总长135米，分三层，旨在通
过仿真救灾现场的严峻条件，人为设置测试科目，使训练人员背负呼吸器，在黑暗、噪音、浓烟、高温的模拟条件下，按照预先设定的工作程序，完成正确穿越各种障碍，并按规定动作完成抢险、伤员营救等工作。它可以测量出训练人员最大身体承受能力和心理承受能力，评定受训人员能否正确使用呼吸器及抢险救援任务等的完成情况。 最 额定电压：380V，允许偏差±10%； 谐波：不大于5%； 频率：50Hz，允许偏差±5%； 3．3 系统组成 系统由以下部分组成:
公司规章制度一、公司形象 1、员工必须清楚地了解公司的经营范围，并能向客户及外界正确地介绍公司业务。 2、在接待公司内外人员的垂询、要求等任何场合，应注视对方，微笑应答，切不可冒犯对方。 3、在任何场合应用语规范，语气温和，音量适中，严禁大声喧哗。 4、遇有客人进入工作场地应礼貌接待，上班时间（包括午餐时间）办公室内应保证有人接待。 5、接听电话应及时，一般铃响不应超过三声，如受话人不能接听，离之最近的职员应主动接听，重要电话作好接听记录，严禁占用公司电话时间太长。 6、员工在接听电话、洽谈业务、发送电子邮件及招待来宾时，必须时刻注重公司形象，按照具体规定使用公司统一的名片、公司标识及落款。 7、员工在工作时间内须保持良好的精神面貌。 8、员工要注重个人仪态仪表，工作时间的着装及修饰须大方得体。 二、生活作息 1、员工应严格按照公司统一的工作作息时间规定上下班。 2、作息时间规定 1）、夏季作息时间表（5月——9月） 上班时间早8：30 午休 12：00——13：30 下班时间晚 18：00 2）、冬季作息时间表（10月——3月） 上班时间早 9：00 午休 12：00——13：30 下班时间晚 17：30 3、员工上下班施行签到制，上下班均须本人亲自签到，不得托、替他人签到。 4、员工上下班考勤记录将作为公司绩效考核的重要组成部分。 5、员工如因事需在工作时间内外出，要向主管经理请示签退后方可离开公司。 6、员工遇突发疾病须当天向主管经理请假，事后补交相关证明。 7、事假需提前向主管经理提出申请，并填写【请假申请单】，经批准后方可休息。 三、卫生规范 1、员工须每天清洁个人工作区内的卫生，确保地面、桌面及设备的整洁。 2、员工须自觉保持公共区域的卫生，发现不清洁的情况，应及时清理。 3、员工在公司内接待来访客人，事后需立即清理会客区。 4、办公区域内严禁吸烟。 5、正确使用公司内的水、电、空调等设施，最后离开办公室的员工应关闭空调、电灯和一切公司内应该关闭的设施。 6、要爱护办公区域的花木。 四、工作要求 1、工作时间内不应无故离岗、串岗，不得闲聊、吃零食、大声喧哗，确保办公环境的安静有序。 2、新入职员工的试用期为二个月，员工在试用期内要按月进行考评。 3、公司内所制定的《员工日程表》是衡量员工完成工作量的依据,要求员工每天要认真、详尽的填写,作为公司考核员工工作量的标准。 4、职员间的工作交流应在规定的区域内进行（大厅、会议室），如需在个人工作区域内
公司先进员工年终获奖一分钟感言范文 公司先进员工年终获奖一分钟感言范文尊敬的公司各级领导.各位同事，大家好很荣幸代表公司先进个人在此发言。首先，请允许我代表所有先进工作者，向关心和支持我们工作的各级领导表示衷心的感激向并肩战斗在各个工作岗位上的同事们致以崇高的敬意回顾一年来的工作，不论我们处于什么样的岗位，都恪尽职守.无私忘我.勤勤恳恳；无论遇到什么样的困难，都以鑫炬人特有的坚韧意志去克服.去战胜。我们今日所取得的成绩，离不开各级领导的培养和帮忙，离不开各位同事的大力支持和配合。你们为我们的成长创造了空间和条件，为我们的工作创造了和谐的氛围和环境，从而促使我们一点一滴地提高。再次感激各级领导和各位同事给予的极大关心和鼓励，给予的充分肯定和荣誉我想，所有获奖的同事们都不会沉醉在今日的荣誉与掌声中。让我们进取行动起来，从我做起.从此刻做起，努力掌握专业知识，不断提高自身综合素质和本事，把过去的成绩作为新的工作起点，以更高的标准严格要求自我，使自我的业务水平在工作中不断提高和完善。我们要继续履行岗位职责，踏实工作.爱岗敬业，始终坚持着旺盛的精神和饱满的工作热情，全心全意投入生产，以此来回报各级领导和各位同事的鼓励和期盼作为公司的一员，“司兴我荣”深深地印在我的心中，昨日我们已经为之努力，明天我们将更加努力。让我们携起手来，把公司的明天建设得更加完美.
更加繁荣昌盛公司先进员工年终获奖一分钟感言范文2尊敬的各位领导.各位同事大家好今日能代表受表彰的“先进工作者”在那里发言，我感到无比的荣幸和激动。首先，请允许我代表本次获得荣誉称号的员工，向关心和支持我们的领导表示衷心的感激向风雨同舟.相互支持.并肩奋斗的信泰同仁们致以崇高的敬意我们在工作中所取得的成绩，是领导以身作则，正确引导的结果，是同事们相互帮忙团结奋斗的结果。今日我们被评为“先进工作者”，但不会沉醉于今日的荣誉和掌声中，我明白，我们还存在很多不足，就像我的不足之处，例如打资料的不细心，出现错别字，准备工作不周到等，这些都是工作中的细节，曾记得李总随口说过的一句话“细节决定成败”，这句话对我来说深有体会，让我明白不论在哪个岗位上，都要注重小事，关注细节，把小事做细，做透，也仅有把小事做好，才能做大事。在日常工作中比别人多思索一点细节，比别人眼里“多做一点活”，否则，任何忽视细节的行为，就会有1的错误导致100的失败。成绩只能说明过去，昨日我努力了，今日.明天我将更加努力。在此，我代表“先进工作者”向各位领导和同事表个态我们将把过去的成绩，作为新的工作起点，以更高的标准严格要求自我，虚心学习他人的长处，注重细节，严格要求自我，正确认识自身工作和价值，正确处理苦与乐，得与失，个人利益与团体利益，工作与家庭的关系，从大局出发，坚持甘于奉献，诚实敬业，不辜负各位领导和同事的期望。要想把事情做好，就必须有一个好的工作态度。
摘要 随着我国汽车保有量的大幅度上升，高新技术产品和装置在汽车上的不断引入和普及与汽车维修业高素质从业人员不足之间的矛盾显得日益突出。发动机电控技术是汽车专业的一门核心技术，理论性与实践性很强。开发发动机电控系统模拟教学实验台，能便于学生认识和学习发动机电控系统的工作原理。发动机电控系统模拟实验台可以广泛应用于科研、教学等方面，通过对发动机工作过程的模拟、显示，可以提高汽车从业人员的知识掌握水平及实际操作能力，增强对汽车电控系统的认识和掌握，为学生学习和掌握发动机电控系统的工作原理提供帮助。 本设计是以教学展示为前提，主要介绍了发动机电控系统的控制内容、发展简史与前景、组成与工作原理，并在此基础上设计电控系统模拟实验台的相关内容。主要包括实验台架的设计、电控系统的零部件布置、电动机转速控制等内容。这个教学实验台能够演示发动机的起动和正常工作过程，并且设置了测量点。通过完成对实验台的设计，可以深刻理解和掌握发动机电控系统的组成和工作原理、机械设计与机械制图的相关知识，最终设计出一款及机械、电控于一体化的产品。 关键词：发动机电控系统；电动机控制；实验台；单片机；PWM
ABSTRACT With significant increase of the number of automobile，the contradiction between high-tech products and devices, the constant introduction in the car and popularization of high-quality vehicle maintenance trade and lack of practitioners become increasingly prominent. Engine electronic control technology is the theoretical and practical of a core technology and theoretical and practical very strong. Electronic control system simulation teaching test can make students to understand and learn the engine electronic control system works easy. Engine electronic control simulation system can be widely used in scientific research, teaching, etc. By displaying of the course of the engine simulation process, it can be employed to improve motor vehicle mastery level of knowledge and practical ability, and enhance the automotive electronic control system of understanding and mastering, for the students to learn and master the engine control system works to help. The design is based on the premise of teaching show, this paper introduces control content system of the engine electronic control, brief history of and prospects for development, composition and working principle and design on the basis of electronic control system simulation test-bed of related content. It mainly includes the design of bench testing, electrical control system layout of components, such as motor speed control. The teaching experiment platform to demonstrate the engine start and normal work processes, and set the measurement points. The design of the test-bed by accomplish can help learns to understand and master the engine electronic control system components, a final design and mechanical and electrical control products in the integration. Key words: Engine Electrical Control System；Motor Control；Test-bed；microcontroller；PWM