当前位置:文档之家› 2008 Fabrication of thin film dye sensitized solar cells with solar to

2008 Fabrication of thin film dye sensitized solar cells with solar to

2008 Fabrication of thin film dye sensitized solar cells with solar to
2008 Fabrication of thin film dye sensitized solar cells with solar to

Fabrication of thin film dye sensitized solar cells with solar to

electric power conversion efficiency over 10%

Seigo Ito ?,Takurou N.Murakami 1,Pascal Comte 1,Paul Liska 1,Carole Gr?tzel 1,

Mohammad K.Nazeeruddin 1,Michael Gr?tzel ?

Laboratoire de Photonique et Interfaces,Institut des Sciences et Ingénierie Chimiques,école Polytechnique Fédérale de Lausanne (EPFL),

Station 6,CH-1015,Lausanne,Switzerland

Available online 14June 2007

Abstract

Techniques of TiO 2film fabrication for dye-sensitized solar cells having a conversion efficiency of global air mass 1.5(AM 1.5,1000W/m 2)solar light to electric power over 10%are reported.Newly implemented fabrication technologies consist of pre-treatment of the working photoelectrode by TiCl 4,variations in layer thickness of the transparent nanocrystalline-TiO 2and applying a topcoat light-scattering layer as well as the adhesion of an anti-reflecting film to the electrode's surface.TiCl 4treatments induce improvements in the adhesion and mechanical strength of the nanocrystalline TiO 2layer.Optimization of the thickness of the TiO 2layer,acting as the working electrode,affects both the photocurrent and the photovoltage of the devices.Covering of the TiO 2photoanode by an anti-reflecting film results in enhancement of the photocurrent.Each of these components of film fabrication exerts a significant influence on the overall photovoltaic parameters of the devices resulting in improvements in the net energy conversion performance.?2007Elsevier B.V .All rights reserved.

Keywords:Dye-sensitized solar cells;Porous TiO 2film;Screen printing;High conversion efficiency;Reproducibility;TiCl 4treatment;Light-scattering layer;Anti-reflecting film

1.Introduction

Dye-sensitized solar cells (DSC)show great promise as an inexpensive alternative to conventional p –n junction solar cells.Investigations into the various factors influencing the photovol-taic efficiency in this novel approach have recently been intensified [1–4].Highly efficient photovoltaic conversions,combined with ease of manufacturing and low production costs,make the DSC technology an attractive approach for large-scale solar energy conversion [5].For the optimization of the DSC components,i.e.,the oxide semiconductor,the sensitizer and the electrolyte,exactitude in reporting the experimental procedures used is indispensable in order to compare the data between the many different laboratories active in this field.

Amongst the concepts fundamental to the development of the dye-sensitized solar cell is the association of a highly porous nanocrystalline TiO 2film (affording a large inherent adsorptive surface area),enhanced in recent designs by a light-scattering topcoat,with a high molar extinction coefficient dye as sensitizer to form the working electrode of the solar cell.Techniques in TiO 2film fabrication are,thus,a very important aspect in the production of highly efficient DSCs.TiO 2film preparation utilizes the techniques of screen-printing for the nanocrystalline and submicron-crystalline-TiO 2film layers as well as a chemical bath deposition for the TiCl 4treatment [6].A photon-trapping effect is induced by the use of the so-called “double layer ”[7],i.e.,the combination of a transparent nanocrystalline TiO 2film with a microcrystalline light-scattering layer,in conjunction with an anti-reflecting film (ARF),thus,enhancing the incident photon-to-electricity conversion efficiency (IPCE),also referred to as the “external quantum efficiency ”.

This manuscript describes the methodical fabrication of the TiO 2electrodes exploring the optimal cell design,while analyzing the influence of various technical procedures on the photovoltaic

Available online at https://www.doczj.com/doc/c63056231.html,

Thin Solid Films 516(2008)4613–

4619

https://www.doczj.com/doc/c63056231.html,/locate/tsf

?Corresponding authors.Tel.:+41216933112;fax:+41216936100.E-mail address:michael.graetzel@epfl.ch (M.Gr?tzel).1

Tel.:+41216933112;fax:+41216936100.

0040-6090/$-see front matter ?2007Elsevier B.V .All rights reserved.doi:10.1016/j.tsf.2007.05.090

performance of highly efficient DSC.A detailed procedure is presented for fabrication of cells showing reproducible conver-sion efficiencies over 10%under standard reporting conditions.2.Experimental details 2.1.Materials

4-tert-butylpyridine (Aldrich),acetonitrile (Fluka),and valer-onitrile (Fluka)were purified by vacuum distillation.Guanidi-nium thiocyanate (Aldrich)and H 2PtCl 6(Fluka)were used as received.H 2O was purified by distillation and filtration (Milli-Q).TiCl 4(Fluka)was diluted with water to 2M at 0°C to make a stock solution,which was kept in a freezer and freshly diluted to 40mM with water for each TiCl 4treatment of the FTO coated glass plates.Iodine (99.999%),(Superpur?,Merck)was used as received.1-butyl-3-methyl imidazolium iodide (BMII)was prepared according to the literature method [8].2.2.Preparation of TiO 2screen-printing pastes

Two types of TiO 2pastes yielding nanocrystalline-TiO 2(20nm,paste A)and microcrystalline-TiO 2(400nm,paste B)particles were prepared,forming respectively the transparent and the light-scattering layers of the photoanode.Scheme 1depicts the

stepwise preparation procedures for the paste (A)containing nanocrystalline-TiO 2(20nm)particles.

2.2.1.20nm particle sized TiO 2colloid:preparation and characterization

An amount of 12g (0.2moles)of acetic acid was added all at once to 58.6gm (0.2moles)of titanium iso-propoxide under stirring at room temperature.The modified precursor was stirred for about 15min and poured into 290ml water as quickly as possible while vigorously stirring (700rpm).A white precipitate was instantaneously formed.One hour of stirring was required to achieve a complete hydrolysis reaction.After adding a quantity of 4ml of concentrated nitric acid,the mixture was heated from room temperature to 80°C within 40min and peptized for 75min.Water was then added to the cooling liquid mixture to adjust the volume to a final 370ml.The resultant mixture was kept in a 570ml titanium autoclave and heated at 250°C for 12h.Following this step,2.4ml of 65%nitric acid was added and the dispersion was treated with a 200W ultrasonic titanium probe at a frequency of 30pulses every 2s.The resultant colloidal solution was concentrated with a rotary-evaporator to contain 13wt.%TiO 2.Finally,it was triply centrifuged to remove nitric acid and washed with ethanol three times to produce a white precipitate containing 40wt.%TiO 2in ethanol and only trace amounts of

water.

Scheme 1.Flow diagram depicting TiO 2colloid and paste used in screen-printing technique for DSC production.

4614S.Ito et al./Thin Solid Films 516(2008)4613–4619

2.2.2.Preparation of screen-printing pastes

Two kinds of pure ethyl cellulose(EC)powders,i.e.,EC(5–15 mPas,#46070,Fluka)and EC(30–50mPas,#46080,Fluka)were dissolved prior to usage in ethanol to yield10wt.%solutions.45g of EC(5–15,#46070)and35g of EC(30–50),#46080)of these 10wt.%ethanolic mixtures were added to a round bottomed rotavap flask containing16g pure TiO2(obtained from pre-viously prepared precipitate)and64.9g of terpineol(anhydrous, #86480,Fluka)and diluted with80ml of ethanol to obtain a final total volume of280ml.This mixture was then sonicated using an ultrasonic horn(Sonics&Materials,Inc),alternating stirring, with a hand mixer(Ultraturrax,IKA),and sonication,for three consecutive times.Ethanol and water were removed from these TiO2/ethyl cellulose solutions by rotary-evaporator(initial temperature40°C and pressure120mbar subsequently reduced to a final pressure of10mbar at40°C).The final formulations of the pastes were made with a three-roll mill(M-50,EXAKT, Germany).The final screen-printing pastes correspond to18wt.% Ti02,9wt.%ethyl cellulose and73wt.%terpineol(paste A).

For the paste used in the light-scattering layers(paste B),10nm TiO2particles which were obtained following the peptization step (particle size is determined at this stage of fabrication)and in a procedure analogous to those of20nm TiO2outlined in Scheme1, were mixed with400nm TiO2colloidal solution(CCIC,Japan)to give a final paste formulation of28.6%400nm-sized TiO2,2.9% 10-nm-sized TiO2and7.2%ethyl cellulose[EC30–50(#46080)] in terpineol.

2.3.Synthesis of ruthenium sensitizer

The synthesis of cis-di(thiocyanato)-N-N′-bis(2,2′-bipyridyl-4-carboxylic acid-4′-tetrabutylammonium carboxylate)rutheni-um(II)(N-719)was reported previously[9].The chromato-graphic purification of N-719was carried out three times on a column of Sephadex LH-20using the literature procedure[10]. The N-719complex was dissolved in water containing two equivalents of tetrabutylammonium hydroxide.The concentrated solution was filtered through a sintered glass crucible and charged onto a Sephadex LH-20column,which was prepared in water. The adsorbed complex was eluted using water.The main band was collected,and the solution pH was lowered to4.3using 0.02M HNO3acid.The titration was carried out slowly over a period of3h.The solution was then kept at?20°C for15h.After allowing the flask to return to ambient temperature(25°C),the precipitated complex was collected on a glass frit and air-dried. The same purification procedure was repeated three times to get pure N-bonded isomer complex.

2.4.Fabrication of porous-TiO2electrodes

In order to obtain an efficient and reproducible photovoltaic DSC performance,surface contamination by iron cations should be avoided,because these ions or iron oxides formed during the subsequent sintering of the TiO2layer enhance charge recombi-nation in photocells[11,12].Indeed we found that deposition of Fe3+by application of an aqueous FeCl3solution to the TiO2 electrode quenches the dye-sensitized photocurrent(J sc)effec-tively.The J sc decreased by30%upon addition of400ppm Fe2O3 [13].In order to exclude iron contamination the equipment used during the preparation of mesoscopic TiO2was made of plastic, titanium or glass,and was washed with an acidic solution prior to use.Plastic tweezers and spatulas were employed throughout.The treatment as mentioned below with solutions of0.1M HCl in ethanol or TiCl4(aqueous)had the effect to remove the iron contamination source.

As shown in Scheme2,to prepare the DSC working electrodes, the FTO glass used as current collector(Solar4mm thickness, 10Ω/□,Nippon Sheet Glass,Japan)was first cleaned in a detergent solution using an ultrasonic bath for15min,and then rinsed with water and ethanol.After treatment in a UV-O3system (Model No.256–220,Jelight Company,Inc.)for18min,the FTO glass plates were immersed into a40mM aqueous TiCl4solution at70°C for30min and washed with water and ethanol.A layer of paste A was coated on the FTO glass plates by screen-printing (90T,Estal Mono,Schweiz.Seidengazefabrik,AG,Thal),kept in a clean box for3min so that the paste can relax to reduce the surface irregularity and then dried for6min at125°C.However, this“leveling”(i.e.,reduction in surface irregularity)time must be controlled visually by the experimentalist since the speed at which this leveling occurs depends on the viscosity of each paste employed.The screen characteristics are as follows:material, polyester;mesh count,90T mesh/cm(or230T mesh/inch);mesh opening,60μm;thread diameter,50μm;open surface,29.8%; fabric thickness,83μm;theoretical paste volume,24.5cm3/m2; K/KS volume,17.0cm3/m2;weight,48g/m2.This screen-printing procedure with paste A(coating,storing and drying)was repeated to get an appropriate thickness of12–14μm for the working electrode.After drying the(paste A)films at125°C,two layers of paste B were deposited by screen-printing,resulting in a light-scattering TiO2film containing400nm sized anatase particles of4–5μm thickness.The electrodes coated with the TiO2pastes were gradually heated under an airflow at325°C for 5min,at375°C for5min,and at450°C for15min,and finally,at 500°C for15min.

The TiO2“double-layer”film thus produced is once again treated with40mM TiCl4solution,as described previously,then rinsed with water and ethanol and sintered at500°C for30min. After cooling to80°C,the TiO2electrode was immersed into a 0.5mM N-719dye solution in a mixture of acetonitrile and tert-butyl alcohol(volume ratio,1:1)and kept at room temperature for20–24h to assure complete sensitizer uptake.

2.5.Preparation of counter Pt-electrodes

To prepare the counter electrode,a hole(1-mm diameter)was drilled in the FTO glass(LOF Industries,TEC15Ω/□,2.2mm thickness)by sandblasting.The perforated sheet was washed with H2O as well as with a0.1M HCl solution in ethanol and cleaned by ultrasound in an acetone bath for10min.After removing residual organic contaminants by heating in air for 15min at400°C,the Pt catalyst was deposited on the FTO glass by coating with a drop of H2PtCl6solution(2mg Pt in1ml ethanol)with repetition of the heat treatment at400°C for 15min.

4615

S.Ito et al./Thin Solid Films516(2008)4613–4619

2.6.Electrolyte

The electrolyte employed was a solution of 0.6M BMII,0.03M I 2,0.10M guanidinium thiocyanate and 0.5M 4-tert-butylpyridine in a mixture of acetonitrile and valeronitrile (volume ratio,85:15).2.7.DSC assemblage

The dye-covered TiO 2electrode and Pt-counter electrode were assembled into a sandwich type cell (Fig.1)and sealed with a hot-melt gasket of 25μm thickness made of the ionomer Surlyn 1702(Dupont).The size of the TiO 2electrodes used was 0.16cm 2(i.e.,4mm ×4mm).The aperture of the Surlyn frame was 2mm larger than that of the TiO 2area and its width was 1mm.The hole in the counter electrode was sealed by a film of Bynel using a hot iron bar (protectively covered by a fluorine polymer film).A hole was then made in the film of Bynel by a needle.A drop of the electrolyte was put on the hole in the back of the counter electrode.It was introduced into the cell via vacuum backfilling.The cell was placed in a small vacuum chamber to remove inside air.Exposing it again to ambient pressure causes the electrolyte to be driven into the cell.Finally,the hole was sealed using a hot-melt ionomer film (Bynel 4702,35μm thickness,Dupont)and a cover glass (0.1mm thickness).In order to have a good electrical contact for the connections to the measurement set-up,the edge of the FTO outside of the cell was roughened slightly with sandpaper or a file.A solder (Cerasolza,Asahi Glass)was applied on each side of the FTO electrodes.The position of the solder was 1mm away from the edge of the Surlyn gasket and hence 4mm away from the side of the photoactive TiO 2layer.

Light reflection losses were eliminated using a self-adhesive fluorinated polymer film (Arktop,Asahi Glass)that served at the same time as a 380nm UV cut-off filter Masks made of black plastic tape were attached on the Arktop filter to reduce scattered light.

2.8.Photovoltaic measurements

Photovoltaic measurements employed an AM 1.5solar simulator equipped with a 450W xenon lamp (Model No.81172,Oriel).The power of the simulated light was

calibrated

Scheme 2.Schematic representation for fabrication of dye-sensitized-TiO 2

electrodes.

Fig.1.Configuration of the dye sensitized solar cells.

4616S.Ito et al./Thin Solid Films 516(2008)4613–4619

to 100MW/cm 2by using a reference Si photodiode equipped with an IR-cutoff filter (KG-3,Schott)in order to reduce the mismatch between the simulated light and AM 1.5(in the region of 350–750nm)to less than 2%[14,15]with measurements verified at two solar-energy institutes [ISE (Germany),NREL (USA)].I –V curves were obtained by applying an external bias to the cell and measuring the generated photocurrent with a Keithley model 2400digital source meter.The voltage step and delay time of photocurrent were 10mV and 40ms,respectively.3.Results and discussion 3.1.TiCl 4treatments

Two consecutive TiCl 4treatments were performed when preparing the TiO 2photoanodes for dye sensitized solar cells,one prior to and one following the screen printing of the mesoscopic (porous)-TiO 2films (Scheme 2).The initial TiCl 4treatment influences positively the TiO 2working electrode in two manners,firstly through enhancing the bonding strength between the FTO substrate and the porous-TiO 2layer,and secondly,by blocking the charge recombination between electrons emanating from the

FTO and the I 3?ions present in the I ?/I 3?

redox couple.Frank et al.[16]concluded from Intensity-Modulated Infrared Spectroscopy (IMIS)analysis that recombination occurs predominantly in the region of the FTO substrate rather than across the depth of the TiO 2film,underlining the utility of applying a TiO 2compact “under ”layer to the FTO glass surface.The second TiCl 4treatment has itself been shown to enhance the surface roughness factor and necking of the TiO 2particles thus augmenting dye adsorption and resulting in higher photocurrent [6].

Fig.2exhibits the dark current –voltage characteristics of two types of electrode surfaces,one consisting merely of FTO conducting glass with the other being TiCl 4treated FTO glass.The onset of the dark current emanating from the non-treated FTO substrate occurs at low forward bias as is clearly discernible on the right diagram where the current is plotted on a logarithmic scale.TiCl 4treatment is shown,however,to suppress the dark current,shifting its onset by several hundred millivolts.This can be

attributed to the fact that the SnO 2is highly doped and its conduction band edge is positively shifted by about 0.5V with respect to that of TiO 2resulting in a much higher electron density in the FTO glass within the investigated potential range.The suppression of dark current following compact TiO 2film formation is indicative of the tri-iodide reduction being enhanced at any exposed part of the FTO substrate in addition to occurring at the TiO 2film itself or at the interface of the dye sensitized-TiO 2and the electrolyte employed in cell fabrication.

Table 1shows the influence of TiCl 4chemical bath deposition on the characteristics of nanocrystalline-TiO 2layers which have been treated versus those layers prepared according to the original procedure [6]used in nanocrystalline-TiO 2film formation.Although the specific surface area decreased by 7.9%following the TiCl 4treatment,the overall weight of TiO 2increased by 28.1%leading to an increase in the TiO 2roughness factor.The augmentation in the roughness factor leads to an absorbance increase of 15.7%.The increase of particle diameter (by 1.9nm)following the TiCl 4treatment implies the generation of

an

Fig.2.Dark I –V curves of smooth electrodes measured in the absence of Ru-dye sensitizer.Left graph:linear current scale:dotted line,bare FTO;solid line,FTO covered with TiO 2layer.Right graph:logarithmic current scale;FTO (bare)[dotted line],FTO/TiO 2[solid line].Compact layer TiO 2on FTO was made using a dual TiCl 4treatment.Sandwich cell configuration as depicted in Fig.1.

Table 1

Characteristics of nanaocrystalline TiO 2layers illustrating the effects of the TiCl 4treatments [1]Film characteristics

Electrode description Nano-TiO 2

TiCl 4-treated nano-TiO 2Average pore diameter/nm 20.218.3Specific surface area/m 2g ?186.0

79.7

TiO 2weight a /mg cm ?2μm ?10.135±0.0030.173±0.003Roughness factor b /μm ?1

116±3

138±2Absorbance at 540c nm/μm ?1

0.159±0.05

0.184±0.06

The optical reference background was obtained using an identical TiO 2electrode after desorption of N-719by soaking in a 0.1M solution of tert-butylammonium hydroxide in acetonitrile.A cover glass was attached to the TiO 2layer surface and the pores in nanocrystalline TiO 2layers were filled with butoxyacetonitrile to decrease the light-scattering effect.Note:the last three characteristics tabulated are “per μm ”electrode thickness.a

The weight-measurement sample area was 16cm 2for a 15μm thickness.b

Roughness factor was obtained by multiplying the specific surface area and TiO 2weight.c

Absorbance measurements were performed with a N719-covered nano-crystalline TiO 2layer at 540nm.

4617

S.Ito et al./Thin Solid Films 516(2008)4613–4619

additional TiO 2layer (of approximately 1nm thickness)on the surface of the nanocrystalline-TiO 2film present in the porous layer.The photocurrent and the conversion efficiency increased by 9.6%and 8.0%,respectively,attributed to the increase of the roughness factor,with its resultant enhanced dye adsorbance,leading to DSC conversion efficiencies of more than 10%.3.2.Effect of the light-scattering TiO 2(anatase)layer A photon-trapping system,the so-called “double-layer ”(i.e.,TiO 2films consisting of transparent nanocrystalline and micro-crystalline light-scattering anatase particles),was used for DSC photocurrent enhancement.Fig.3exhibits the photovoltaic improvements engendered by using the double-layer TiO 2films.The total active cell area was 0.25cm 2and the cell area illuminated through the aperture of the mask was 0.16cm 2,respectively.With no light-scattering layer present the photo-voltaic parameters measured were J sc =15.6mAcm ?2,V oc =791mV,FF=0.740and η=9.12%.Upon addition of the light-scattering layer,these same photovoltaic characteristics dis-played an enhancement,i.e.,J sc =18.2mAcm ?2,V oc =785mV ,FF=0.704and η=10.1%.

The light-scattering layer has been shown to act not only as a photon-trapping system but to be equally active in photovoltaic generation itself [17].Cell efficiencies measured were 5%in dye sensitized solar cells using only the light-scattering TiO 2layer.

Losses of approximately 4%on the glass substrate due to reflection of incident light in DSC can be partially circumvented by adding an anti-reflecting film,which acts simultaneously as a 380nm UV cut-off filter.Fig.4compares the incident photon-to-electron conversion efficiency (IPCE),or “external quantum efficiency ”of a cell with and without the anti-reflecting layer.

3.3.Impact of nanocrystalline-TiO 2layer thicknesses on photovoltaic performance

Variation in thickness of the nanocrystalline-TiO 2layer is a crucial factor in optimizing photovoltaic performances of DSC.Although precise measurements of the exact layer thickness is difficult to perform following formation of the “double-layer ”electrode,the nanocrystalline-TiO 2layer can be measured prior to sintering using a surface profiler.In order to facilitate depth estimations and to make useful projections of the final thickness of the nanocrystalline-TiO 2layer comprised in the “double layer ”electrode following sintering,a calibration curve was made.The ratio “before sintering ”/“after sintering ”,described by a linear relationship going through the origin,yields a shrinkage factor of slightly under unity (i.e.,0.942)for 20nm TiO 2sized particulate films.By using this calibration line,a relationship between nanocrystalline-TiO 2film thickness and the resultant DSC conversion efficiency can be obtained,the optimum film thickness to produce highly efficient DSC being 12–14μm (with the addition of an adhered ARF),as shown in Fig.5

.

Fig.3.I –V curves comparing TiO 2electrodes produced using the standard procedure [6](thick line),without TiCl 4treatment (dotted line),and without a light-scattering layer (thin line).Cell characteristics described in text.The total active area of the cell was 0.25cm 2;the illuminated part corresponding to the aperture area of the black mask was 0.16cm 2.The V oc loss due to partial illumination of the active area is about 20–30mV depending on J sc .Pho-tovoltaic characteristics on TiO 2electrodes were:standard procedure:J sc =18.2mA cm ?2,V oc =789mV ,FF=0.704and η=10.1%;no TiCl 4treatment,J sc =16.6mA cm ?2,V oc =778mV ,FF=0.731and η=9.4%;no light-scattering layer,J sc =15.6mA cm ?2,V oc =791mV ,FF=0.740and η

=9.12%.

Fig.4.IPCE of DSC with and without adhesion of ARKTOP anti-reflecting

film.

Fig.5.Photoconversion efficiency as a function of nanocrystalline TiO 2layer thickness.Illuminated-TiO 2and aperture areas of cells are 0.16cm 2and 0.25cm 2,respectively [18].

4618S.Ito et al./Thin Solid Films 516(2008)4613–4619

3.4.Reproducibility of DSC fabrication

Fig.6depicts a histogram showing the performance statistics of twelve devices produced within 24hours of each other by following the procedure described above,optimizing cell performance parameters through TiCl 4treatments,nanocrystal-line-TiO 2layer thickness selection as well as by use of an anti-reflecting film (Arktop).Conversion efficiencies greater than 10%were obtained with all devices,the average being 10.2±0.2%.This statistical graph shows convincingly the excellent reproducibility of the method elaborated here for the fabrication of highly efficient dye sensitized solar cells.4.Conclusions

The present study systematically outlines the step-by-step procedures to follow in producing screen-printing pastes used to form both the transparent and light-scattering layers of TiO 2electrodes used in DSC devices.A methodological approach to the actual TiO 2electrode fabrication is likewise outlined complementing other systematic studies of experimental proce-dures [18].Adhesion of an anti-reflecting film (ARF)is seen to enhance the IPCE or “external quantum efficiency ”of the devices to reach up to 94%at wavelengths close to the absorption maximum of the sensitizer.Optimization of the nanocrystalline-TiO 2layer thickness (12–14μm)is shown to play a crucial role in cell design.

The protocol established here should assist researchers involved in the fabrication and characterization of small DSC laboratory cells as well as in the production of commercialized

https://www.doczj.com/doc/c63056231.html,bination of all of these “state of the arts ”procedures renders the production of reproducible,highly efficient (N 10%)dye-sensitized solar cells easily attainable.Acknowledgement

This work was supported by a grant from the Swiss Federal Energy Office (OFEN).Aid in manuscript preparation by Dr.Daibin Kuang and experimental assistance by Drs.Shaik Zakeeruddin and Peter Pechy is gratefully acknowledged.References

[1]B.O'Regan,M.Gr?tzel,Nature 335(1991)737.[2]M.Gr?tzel,Nature 414(2001)338.

[3]A.Hagfeldt,M.Gr?tzel,Acc.Chem.Res.33(2000)269.

[4]U.Bach,D.Lupo,https://www.doczj.com/doc/c63056231.html,te,J.E.Moser,F.Weiss?rtel,J.Salbeck,H.Spreitzert,M.Gr?tzel,Nature 395(1998)544.

[5]G.Smestad,Sol.Energy Mater.Sol.Cells 32(1994)259.

[6]S.Ito,P.Liska,R.Charvet,https://www.doczj.com/doc/c63056231.html,te,P.Péchy,Md.K.Nazeeruddin,S.M.Zakeeruddin,M.Gr?tzel,https://www.doczj.com/doc/c63056231.html,mun.(2005)4351.

[7]P.Wang,S.M.Zakeeruddin,https://www.doczj.com/doc/c63056231.html,te,R.Charvet,R.Humphry-Baker,M.Gr?tzel,J.Phys.Chem.,B 107(2003)14336.

[8]P.Bonh?te,A.P.Dias,M.Armand,N.Papageorgiou,K.Kalyanasundaram,M.Gr?tzel,Inorg.Chem.35(1996)1168.

[9]

Md.K.Nazeeruddin,S.M.Zakeeruddin,R.Humphry-Baker,M.Jirousek,P.Liska,N.Vlachopoulos,V .Shklover,Christian-H.Fischer,M.Gr?tzel,Inorg.Chem.38(1999)6298.

[10]Md.K.Nazeeruddin,F.De Angelis,S.Fantacci,A.Selloni,G.Viscardi,P.Liska,S.Ito,B.Takeru,M.Gratzel,J.Am.Chem.Soc.127(2005)16835.[11]N.J.Cherepy,D.B.Liston,J.A.Lovejoy,H.Deng,J.Z.Zhang,J.Phys.Chem.,B 102(1998)770.

[12]B.A.Gregg,F.Pichot,S.Ferrere,C.L.Fields,J.Phys.Chem.,B 105(2001)1422.

[13]A.Kay,PhD Thesis,Ecole Polytechnique Fédérale de Lausanne,Switzerland (1994).

[14]

M.K.Nazeeruddin,P.Péchy,T.Renouard,S.M.Zakeeruddin,R.Humphry-Baker,https://www.doczj.com/doc/c63056231.html,te,P.Liska,L.Cevey,E.Costa,V .Shklover,L.Spiccia,G.B.Deacon,C.A.Bignozzi,M.Gr?tzel,J.Am.Chem.Soc.123(2001)1613.

[15]S.Ito,H.Matsui,K.Okada,S.Kusano,T.Kitamura,Y .Wada,S.Yanagida,Sol.Energy Mater.Sol.Cells 82(2004)421.

[16]K.Zhu,E.A.Schiff,N.-G.Park,J.Van de Lagemaat,A.J.Frank,Appl.Phys.Lett.80(2002)685.

[17]

Z.Zhang,S.Ito,B.O'Regan,D.Kunag,S.M.Zakeeruddin,P.Liska,R.Charvet,https://www.doczj.com/doc/c63056231.html,te,Md.K.Nazeeruddin,P.Péchy,R.Humphry-Baker,T.Koyanagi,T.Mizuno,M.Gr?tzel,Z.Phys.Chem.221(2007)319.

[18]

S.Ito,Md.K.Nazeeruddin,P.Liska,https://www.doczj.com/doc/c63056231.html,te,R.Charvet,P.Péchy,M.Jirousek,A.Kay,S.M.Zakeeruddin,M.Gr?tzel,Prog.Photovolt.14(2006)

589.

Fig.6.Histogram depicting reproducibility of DSC conversion efficiencies.Reported values of 12DSC devices produced with a 24hour time period.

4619

S.Ito et al./Thin Solid Films 516(2008)4613–4619

(完整word)北师版高中英语必修3翻译

必修三 1航行到美洲的北欧海盗 北欧海盗是第一批到达美洲的欧美人。早在哥伦布起航之前,他们就已经到达那里了。 北欧海盗的祖先来自于斯堪地那维亚半岛。公元8世纪到10世纪期间,他们控制着北欧海绵和沿海地区。大约到公元900年,北欧很多地方都有海盗居住。公元982年,冰岛生活着多达一万人的北欧海盗,就在此时,一个叫红发埃里克的人决定走向西远航。 根据冰岛和挪威的传说,红发艾里克银犯谋杀案而惹上麻烦,并被迫离开冰岛。埃里克到达达格陵兰岛后,发现他登陆的地方可以居住,返回冰岛,告诉人么哪有管格陵兰岛的事情,病说服一些人与他一起回到格陵兰岛,埃里克再次起航时,有25艘船与他同行,但其中只有14艘最终到达格陵兰岛。 红发埃里克登上格陵兰岛不久,一个叫比阿尼的人也从冰岛起航来寻找埃里克一行人。比阿尼希望找到和埃里克在一起的父亲,但大风使他偏离航线,刮到一个不知名的地方,从哪里他最终抵达格陵兰岛。 1002年红发埃里克的儿子利夫打算继续向西航行,他和比阿尼一同商量他们的在行计划。利夫依照比阿尼的指点。据说航信到了现在的加拿大海岸,他又继续南行至现在叫纽芬兰的岛屿。 我们从挪威和冰岛记载下来并流传几个世纪的传说中得知红发埃里克和利夫的事迹。他们是记载中最早航行到达美洲的欧洲人。 3水下世界-------观赏海洋生物的最佳地点 这里有北极熊,还有一座真正的冰川!你只能看见冰山水上的一小部分,而水下部分是水上部分的三倍。你可以再给海豹喂食时观看海豹,看看那些不爱运动却非常友好的动作敏捷的企鹅。你一定会爱上他们的! 海底 看看世界上最美的珊瑚和最奇异的鱼类,看鱼飞翔着,闯过水面,与其他鱼类相比,他们不算绚丽多姿,但游姿却很美。 海洋剧院 看着聪明的海豚,精彩的表演每两小时一场。 探索他 这里是专为小孩子设计的,在这里,孩子们可以亲手接触摸螃蟹和其他小动物,还可以在这个令人兴奋的环境里学习到关于海滩上日常生活的知识。 虚拟航海 这是我们水管最新,最具有吸引力的活动,来和我们一起进行模拟航行吧!到海底走一走,看一看世界上最奇异的鱼。 最吵的鱼:有些鱼发出的声音几乎是你讲话声音的两倍,你绝对不会找到比他们更吵闹的鱼。 最漂亮的鱼:有的鱼用身体发光一心其他鱼靠近人后吃掉他们,这些的嘴巨大无比,可以吃掉和自己体积一样大的鱼。要当心哦! 最小的鱼:仔细找找这种世界上最小的鱼,他们还不及你家的苍蝇大。 和海豚一起游泳!直接面对海洋中最具有杀伤力的动物——大白鲨 快来参观吧,还有好多动物呢!22日前特价,尽快定票吧!每天早上10点开门。晚上7点关门 4海洋故事 B三年前,我遇到了一间可怕的事。6个小时的恐惧情形让我身心俱毁。你现在回认

球团竖炉烘干安全技术操作规程

吉林恒联编号: 精密铸造科技有限公司技术操作规程生效日期: 年月 编制: 审核: 竖炉烘干机岗位操作规程批准: 一、适用范围:本规程适用于竖炉烘干岗位的操作。 二、主要设备参数 1、干燥机 3、运输皮带机 三、技术操作要求 ①烘干炉操 1、首次引煤气烘炉操作 (1)新建或大修后的烘干炉在点火之前应进行烘炉。 (2)烘炉前首先将煤气引至烘干混合机前煤气管道盲板处。打开烘干混合机前煤气管道盲板前煤气放散阀,向厂内通往烘干混合机的高炉煤气主管道中通氮气吹扫,待煤气放散阀冒氮气10分钟后,关闭厂内高炉煤气主管道手动蝶阀,打开手动盲板阀,然后,再打开手动蝶阀,引煤气至烘干混合机前煤气管道盲板处,关闭烘干混合机前煤气管道盲板前煤气放散阀。(3)烘炉操作 烘炉的作用主要是蒸发耐火砌体内的物理水和结晶水,并提高砌砖泥浆的强度和加热砌体,使炉体达到要求的一定温度,以便投入生产。 烘炉应严格按烘炉曲线进行,一般可分为三个阶段: a低温阶段:烘烤温度从常温(20℃)至300℃。 这时主要是蒸发烘干炉砌体中的物理水。升温要求缓慢(10℃/h),以防止急骤升温而造成耐火砖及砖缝开裂,并在300℃时需要有一定的保温时间(一般为24小时)。这阶段一般用木

柴。 b中温阶段:烘烤温度在300℃~600℃。 主要是脱去砌体耐火泥浆生料粉中的结晶水。升到500℃时须要保温8~10小时,到600℃时为彻底使砌体泥浆发生相变,使其强度提高,因此要保温8~10小时,中温阶段升温可稍快(15℃~20℃/h)。这阶段一般用低压煤气。 c高温阶段:烘烤温度600℃~900℃ 主要是加热砌体,升温速度可快些(20℃/h),为了使砌体的温度达到均匀,也可进行保温(一般为8小时)。这阶段可使用高压煤气。 烘烤温度再往上升,升温速度可以加快到30-50℃/h,直到生产所需要的温度。 900℃ 20℃30 54 68 78 85 95 105小时 竖炉烘炉曲线图 2、正常生产中的引煤气点火操作 (1)引煤气前通知作业长到现场,得到中控同意后通知煤气加压站做好送气准备; (2)检查煤气放散阀是否在开位,煤气烧咀前阀门是否关闭,盲板前电动煤气蝶阀关闭;(3)向烘干混合机前煤气管道内通氮气吹扫,待煤气放散阀冒氮气十分钟后,倒盲板引煤气至烧咀前阀门处; (4)然后进行煤气检验,合格后方可进行点火; (5)点火时煤气压力要大于10000Pa;在炉膛温度大于750℃可直接引煤气点火,否则要用明火点燃。点火时要缓缓开启烧咀阀门,待煤气点着后,将煤气放散阀关死,并调节煤气与空气比例,使燃烧正常进行。 点火时要注意:

球团生产工艺介绍

球团生产工艺介绍 球团生产工艺是一种提炼球团矿的生产工艺,球团与烧结是钢铁冶炼行业中作为提炼铁矿石的两种常用工艺。球团矿就是把细磨铁精矿粉或其他含铁粉料添加少量添加剂混合后,在加水润湿的条件下,通过造球机滚动成球,再经过干燥焙烧,固结成为具有一定强度和冶金性能的球型含铁原料。 一、球团生产工艺的发展 由于天然富矿日趋减少,大量贫矿被采用;而铁矿石经细磨、选矿后的精矿粉,品位易于提高;过细精矿粉用于烧结生产会影响透气性,降低产量和质量;细磨精矿粉易于造球,粒度越细,成球率越高,球团矿强度也越高。综上所述原因,球团生产工艺在进入21世纪后得到全面发展与推广。 如今球团工艺的发展从单一处理铁精矿粉扩展到多种含铁原料,生产规模和操作也向大型化、机械化、自动化方向发展,技术经济指标显著提高。球团产品也已用于炼钢和直接还原炼铁等。球团矿具有良好的冶金性能:粒度均匀、微气孔多、还原性好、强度高,有利于强化高炉冶炼。 二、球团法分类 1、高温固结: (1)氧化焙烧:竖炉、带式机、链篦机-回转窑、环式焙烧机。 (2)还原焙烧:回转窑法、竖炉连续装料法、竖炉间歇装料法、竖罐法、带式机法。(3)磁化焙烧:竖炉法 (4)氧化-钠化焙烧:竖炉法、链篦机-回转窑。 (5)氯化焙烧:竖炉法、回转窑法。 2、低温固结: (1)水泥冷粘结法 (2)热液法 (3)碳酸化法 (4)锈化固结法 (5)焦化固结法 (6)其他方法 三、球团原理 球团生产一般流程:原料准备→配料→混匀(干燥)→造球→布料→焙烧→冷却→成品输出

球团焙烧过程:干燥→预热→焙烧→均热→冷却 四、球团工艺流程图 球团车间平面分布图 新配料料场新配-1 新配-2 新配-3 新配-4 新配-5 老配-2 老配-1 老配料仓 老配-3老配-4 烘干出料 润磨出料 润磨 室 1#烘干室 1#水泵 房办公室休息室 球-4 球-1 造球室 成-1 1#落地仓 1#链板 1#环冷机 1#回转窑 1#链篦机 1#布料 球-3 球-2 返-3 返-2 返-6 返-5 返-4 球-6 2# 布料 2#链篦机2#回转窑 2#环冷机 2# 链板 成-3成-4 2#落地仓 维修区域 维修值班室 球-5 球 -5 转 运站老配料料场 2#水泵房 喷煤系统2# 烘干室 主控楼 北

(完整版)北师大版高中英语单词表

必修一 Learning to learn Questionnaire 问卷,调查表 Matter 要紧,有重大关系 Partner 合作者,搭档 Unit 1 Warm up Lifestyle 生活方式 *shepherd 牧羊人 Peaceful 平静的,和平的 Relaxing 轻松的,放松的 Stressful 充满压力的,紧张的 Suppose 认为,猜想 Lesson 1 *series 系列节目;系列 TV series 电视连续剧 Cartoon 卡通片,动画片 Talk show 谈话节目,现场访谈 *complain 抱怨;投诉 *couch 长沙发,睡椅 Couch potato 终日懒散在家的人 Switch 转换,转变 Switch on 把开关打开,接通 Switch over 转换频道,转变 Switch off 把关掉,关上 BBC= British Broadcasting Corporation 英语广播公司 Portable 轻便的,手提(式)的 Remote 遥远的 Remote control 遥控 *workaholic 工作狂 Paperwork 日常文书工作 Alarm 警报,警告器 Alarm clock 闹钟 Go off (铃,爆竹等)响 Take up 占据 Be filled with 充满着 Urgent 急迫的,紧急的 Document 公文,文件 Midnight 午夜,半夜 Bored 厌烦的,不感兴趣的 Lesson 2 Stress 压力 Studio 演播室,工作室Expert 专家 Suffer 遭受(痛苦),感到疼痛Suffer from 忍受,遭受Pressure 压力 Social 社交的,社会的 Reduce 减少,降低 Organize 组织 Diet 饮食,节食 Prefer 更喜欢,宁愿 Stand 忍耐,忍受 Lesson 3 Volunteer 志愿者 Graduate 毕业 Minus 零下,负 Basin 脸盆 Challenge 挑战 Support 支持,支撑 Dial 拨(电话号码) Design 设计 Advertisement 广告Presentation 表演,展示 *slove 解决,解答 Lesson 4 Accountant 会计,会计师Tube (英)地铁 Crowded 拥挤的 Nearby 附近的 在附近 Otherwise 否则,另外Forecast 预报,预测 Crowed 人群,一伙人 Lung 肺 Sickness 疾病 Distance 距离 Distance learning 远程学习Cigar 雪茄烟 Communication Workshop At the moment 此刻,目前Over the years 数年间 *survey 调查 Classical 古典的 Mini-skirt迷你裙,超短裙Formal 正式的,合礼仪的Cycle 骑自行车

(完整word版)北师大版高中英语单词

必修一Learning to learn Questionnaire问卷,调查表 Matter要紧,有重大关系 Partner合作者,搭档 Unit 1 Warm up Lifestyle生活方式 *shepherdxx Peaceful平静的,和平的 Relaxing轻松的,放松的 Stressful充满压力的,紧张的Suppose认为,猜想 Lesson 1 *series系列节目;系列 TV series电视连续剧 Cartoon卡通片,动画片 Talk show谈话节目,现场访谈 *complain抱怨;投诉 *couchxx发,睡椅 Couch potato终日懒散在家的人

Switch转换,转变 Switch on把开关打开,接通Switch over转换频道,转变Switch off把关掉,关上 BBC=BritishBroadcastingCorporation 英语广播公司 Portable轻便的,手提(式)的Remote遥远的 Remote control遥控 *workaholic工作狂 Paperwork日常文书工作 Alarm警报,警告器 Alarm clock闹钟 Go off(xx,爆竹等)响 Take up占据 Be filled with充满着 Urgent急迫的,紧急的Document公文,文件 Midnight午夜,半夜 Bored厌烦的,不感兴趣的Lesson 2

Stress压力 Studio演播室,工作室Expert专家Suffer遭受(痛苦),感到疼痛Suffer from忍受,遭受 Pressure压力 Social社交的,社会的 Reduce减少,降低 Organize组织 Diet饮食,节食 Prefer更喜欢,宁愿 Stand忍耐,忍受 Lesson 3 Volunteer志愿者 Graduate毕业 Minus零下,负 Basin脸盆 Challenge挑战 Support支持,支撑 Dial拨(电话号码) Design设计 Advertisement广告

北师大版高中英语必修一课文电子版

Unit 1 Lifestyles Warm-up Tapescript 1 Football player: Being famous isn’t easy, you know. I travel a lot – I have matches in different countries. But my job is exciting, very exciting! I love the matches, the people cheering, know what I mean? 2 Student: My dad says these are the best days of my life –but I’m not so sure! You know, I’ve got lots of work to do and there’s not much time really. I also play football for the school team and we have to do training three nights a week. 3 Shepherd: I love the animals and I love nature. It’s peaceful, and there’s no one to tell me what to do. But it’s not so good when the weather’s bad! 4 Business manager: I’m very busy, and I don’t have time to see my husband and children. Mmmm and my life is very stressful, I suppose. I mean, I have to deal with lots of money. But I find it really exciting. 1 A Perfect Day? A Couch Potato Forty-three-year-old Brian Blakey from Birmingham is sitting on his sofa and telling me about his perfect day.

球团工艺及生产

球团工艺及生产

————————————————————————————————作者:————————————————————————————————日期:

球团工艺及生产 把细磨铁精矿粉或其他含铁粉料添加少量添加剂混合后,在加水润湿的条件下,通过造球机滚动成球,再经过干燥焙烧,固结成为具有一定强度和冶金性能的球型含铁原料。??球团矿生产的流程:? 一般包括原料准备、配料、混合、造球、干燥和焙烧、冷却、成品和返矿处理等工序,如下图所示。 球团矿的生产流程中,配料、混合与烧结矿的方法一致;将混合好的原料经造球机制成10-25mm的球状。 1.球团矿的概念?把细磨铁精矿粉或其他含铁粉料添加少量添加剂混合后,在加水润湿的条件下,通过造球机滚动成球,再经过干燥焙烧,固结成为具有一定强度和冶金性能的球型含铁原料。 球团生产与烧结生产一样,是为高炉提供“糖料”的一种加工方法,是将细磨精矿或粉状物料制成能满足高炉冶炼要求的原料的一个加工过程。将准备好的原料(细磨精矿或其他细磨粉状物料、添加剂等),按一定比例经过配料、混匀,制成一定尺寸的小球,然后采用干燥焙烧或其他方法使其发生一系列的物理化学变化而硬化固结,这一过程即为球团生产过程,其产品即为球团矿。球团矿分酸性球团矿和碱性球团矿。由于酸性球团矿生产操作较易控制,且品位高,强度好,同时,高炉冶炼也需要酸性球团与高碱度烧结矿配合使用。 ?2.球团矿生产迅速发展的原因:?◆天然富矿日趋减少,大量贫矿被采用。 铁矿石经细磨、选矿后的精矿粉,品位易于提高。

过细精矿粉用于烧结生产会影响透气性,降低产量和质量。?细磨精矿粉易于造球,粒度越细,成球率越高,球团矿强度也越高。?◆球团法生产工艺的成熟。?从单一处理铁精矿粉扩展到多种含铁原料。?生产规模和操作也向大型化、机械化、自动化方向发展。 技术经济指标显著提高。 球团产品也已用于炼钢和直接还原炼铁等。 ◆球团矿具有良好的冶金性能:粒度均匀、微气孔多、还原性好、强度高,有利于强化高炉冶 ?球团矿生产中的主要设备: 炼。? 圆盘造球机:将焦炭粉、石灰石粉或生石灰、铁精矿粉混合后,输入圆盘造球机上部的混合料仓内,均匀地向造球机布料,同时由水管供给雾状喷淋水,倾斜(倾角一般为40一50°)布置的圆盘造球机,由机械传动旋转,混合料加喷淋水在圆盘内滚动成球。 【烧结设备】圆盘造球机工作原理 ?圆盘造球机用于铁矿粉造球,它是各类球团厂的主要配套设备之一。将焦炭粉、石灰石粉或生石灰、铁精矿粉混合后,输入圆盘造球机上部的混合料仓内,均匀地向造球机布料,同时由水管供给雾状喷淋水,倾斜(倾角一般为40一50°)布置的圆盘造球机,由机械传动旋转,混合料加喷淋水在圆盘内滚动成球,通过粒度刮刀将球的粒度控制在5一15毫米。造好的生球落入输送皮带上,经辊轴筛进行筛分,小于5毫米和大于15毫米的返回到混合机。?主要用到的自动化产品:断路器、接触器、电动机?带式焙烧机:带式焙烧机工艺使球团焙烧的整个工艺过程——干燥、预热、焙烧、冷却都在一个设备上完成,具有工艺过程简单、布置紧凑、所需设备吨位轻等特点,为工厂缩小占地面积、减少工程量、实现焙烧气体的循环利用以及降低热耗和电耗创造了条件。? 主要用到的自动化产品:断路器、接触器、电动机 带式焙烧工艺介绍 带式焙烧工艺可以说是受带式烧结机的启示而发展起来的。?1、带式焙烧机不同于带式烧结机 细磨铁精矿球团的焙烧和铁矿粉的烧结,在固结原理上有着本质上的不同,致使其在工业 生产技术上也有着很大的不同。因而要想把一般的烧结机改造成带式焙烧机将是十分复杂和困难的。?带式焙烧机从外形上看,和烧结机十分相似,但在设备结构上存在很大的区别。如,台车的结构和支架的承力,风箱的分布和密封的要求.上部炉罩的设置和密封,风流的走向(不像烧结机那样是单一的抽风,而是既有抽风又有鼓风),布料方式,成品的排出和台车运行速度等,都不相同,特别是本体的材质更是完全不同。为了能长期安全地承受最高焙烧气体的温度(≥1300 ℃),而不得不采用耐高温性能极好的特殊合金钢。在国外带式焙烧机发展的过程中,曾因材质不过关而一度受挫,而使得同时正在开发的链篦机—回转窑得到了极大的发展。因为链篦机—回转窑工艺是将焙烧过程的最高温度段放在设有耐火炉衬的回转窑中进行,这样就顺利解决了在高温焙烧中的材质问题。而带式焙烧机在使用铺底铺边料和台车采用耐高温合金特殊钢的材质后才得以过关并获得大发展。 2、带式焙烧机工艺的优点 1)球团焙烧的整个工艺过程——干燥、预热、焙烧、冷却都在一个设备上完成,具有工艺过程简单、布置紧凑、所需设备吨位轻等特点,为工厂缩小占地面积、减少工程量、实现焙烧气体的循环利用以及降低热耗和电耗创造了条件。?2)能适应扩大生产规模的要求和实现大型化的要求。其最大已达到750 m2,单机产量达500万t以上。 3)对原料的适应性比竖炉强。这是因为在整个焙烧过程中,球团都处于静料层状态,不会因升温过程中球团本身强度的变化(时高时低)和球与球之间的相对运动而产生粉末。因而带

北师大版高中英语单词表

北师大版高中英语单词表 北师大版高中英语模块一单词表(English)Unit 1Unit 2Unit 3 Unit1 Learning to learn questionnaire 问卷,调查表;matter要紧,有重大关系;partner搭挡,合作者; Warm-up lifestyle生活方式;shepherd牧羊人; peaceful和平的;平静的;relaxing轻松的,放松的;stressful轻松的,放松的;suppose认为,猜想 ----------------------- Lesson 1 series连续;系列,丛书TV series电视连续剧cartoon卡通片,动画片talk show谈话节目,现场访谈complain抱怨,投诉couch睡椅,长沙发 couch potato终日懒散在家的人switch转换,转变 switch on把开关打开,接通switch off把关掉,关上switch over转换频道,转变play戏剧,短剧 BBC英国广播公司portable轻便的,手提(式)的remote遥远的remote control workaholic工作第一的人,专心工作的人 paperwork日常文书工作alarm警报,警告器 alarm clock闹钟(爆竹,铃等)响 go off

take up占据be filled with充满着urgent急迫的,紧急的personal私人的,个人的document公文,文件midnight午夜,半夜 bored厌烦的,不感兴趣的 ----------------------- Lesson 2 stress压力studio工作室,演播室expert专家suffer感到疼痛,遭受(痛苦) suffer from 忍受, 遭受pressure压力 social爱交际的;社交的reduce减少降低organize组织diet饮食,节食 stand忍耐,忍受prefer更喜欢,宁愿 ----------------------- Lesson 3 volunteer志愿者graduate毕业 minus负,零下basin水盆,脸盆challenge挑战support&支持;支撑 dial拨(电话号码) design&设计advertisement广告presentation表演,展示solve解答,解决 ----------------------- Lesson 4 accountant会计,会计师tube(英)地铁crowded拥挤的nearby附近的;在附近

炼钢生产流程图解

钢铁生产工艺主要包括:炼铁、炼钢、轧钢等流程。 (1)炼铁:就是把烧结矿和块矿中的铁还原出来的过程。焦炭、烧结矿、块矿连同少量的石灰石、一起送入高炉中冶炼成液态生铁(铁水),然后送往炼钢厂作为炼钢的原料。 (2)炼钢:是把原料(铁水和废钢等)里过多的碳及硫、磷等杂质去掉并加入适量的合金成分。 (3)连铸:将钢水经中间罐连续注入用水冷却的结晶器里,凝成坯壳后,从结晶器以稳定的速度拉出,再经喷水冷却,待全部凝固后,切成指定长度的连铸坯。 (4)轧钢:连铸出来的钢锭和连铸坯以热轧方式在不同的轧钢机轧制成各类钢材,形成产品。 炼钢工艺总流程图

炼焦生产流程:炼焦作业是将焦煤经混合,破碎后加入炼焦炉内经干馏后产生热焦碳及粗焦炉气之制程。

烧结生产流程:烧结作业系将粉铁矿,各类助熔剂及细焦炭经由混拌、造粒后,经由布料系统加入烧结机,由点火炉点燃细焦炭,经由抽气风车抽风完成烧结反应,高热之烧结矿经破碎冷却、筛选后,送往高炉作为冶炼铁水之主要原料。 高炉生产流程:高炉作业是将铁矿石、焦炭及助熔剂由高炉顶部加入炉内,再由炉下部鼓风嘴鼓入高温热风,产生还原气体,还原铁矿石,产生熔融铁水与熔渣之炼铁制程。 转炉生产流程:炼钢厂先将熔铣送前处理站作脱硫脱磷处理,经转炉吹炼后,再依订单钢种特性及品质需求,送二次精炼处理站(RH真空脱气处理站、Ladle Injection盛桶吹射处理站、VOD真空吹氧脱碳处理站、STN搅拌站等)进行各种处理,调整钢液成份,最后送大钢胚及扁钢胚连续铸造机,浇铸成红热钢胚半成品,经检验、研磨或烧除表面缺陷,或直接送下游轧制成条钢、线材、钢板、钢卷及钢片等成品。

球团竖炉

球团竖炉 一种用于焙烧冶金球团的竖炉,属于冶金设备的技术领域。它包括由炉墙组成的炉膛,设于炉膛下端的锁风卸料装置,炉膛上部的球团料进口和设于炉膛内中部的破碎辊,炉墙下部设有供风喷口,炉膛内设有与炉膛内外相通的燃料管道,所述燃料管道炉膛内部分设有燃料喷嘴。它结构简单,燃料直接在炉内燃烧,炉宽方向温度均匀,热效率高,焙烧带供热足,球团产量高,质量均匀。 包括由炉墙(1)组成的炉膛,设于炉膛下端的锁风卸料装置(8),设于炉膛上部的球团料进口和设于炉膛内中部的破碎辊(5),其特征在于:炉墙(1)下部设有供风喷口(6),炉膛外设有与炉膛内相通的燃料管道(3),所述燃料管道(3)炉膛内部分设有燃料喷嘴(2)。 ★TCS球团竖炉专利技术简介 TCS球团竖炉突破了竖炉大型化这一国际难题,成功地利用自身余热将助燃风温度预热到230℃以上。经河北省科学技术厅组织的国内球团专家委员会进行技术成果鉴定,确定为国内先进水平,取得了投资省、占地省、能耗低、成本低、质量高的实际生产效果,属于钢铁企业高炉精料的“短平快”技改项目。目前TCS球团竖炉的开发技术已走向系列化、大型化,年产6.6万吨、10万吨、30万吨、50万吨、60万吨、70万吨、80万吨已经实施应用,100万吨已设计完成。我公司“TCS球团竖炉”已发展到第六代技术,其中节能型TCS球团竖炉直接利用生产过程产生的600~800℃冷却风作助燃风,充分利用余热,减少了热量损失,节约了能源。 ★TCS球团竖炉专利技术特点: 1、炉顶气动布料器,结构简单,工作可靠。 2、上下两层烘干床,烘干面积大,且气体温度可分区控制,因而可实现变温变向慢速干燥,减少了过湿现象和爆裂现象。 3、烘干床具有气筛和固定筛作用,可将大部分粉末和返矿提前分离并排出炉外,改善了焙烧带料柱透气性和气流分布,增强了对原料和操作波动的适应能力,使TCS球团竖炉的利用系数高达7-8.33(t/m2.h)。 4、焙烧带喷火口和燃烧室置于炉子内部,从内向外烧,充分利用边缘效应,提高了喷火口对面外墙附近低温区域的气流量和温度,使整个焙烧带气流和温度分布趋于均匀合理。 5、环型焙烧带不需加大焙烧带的宽度,即可方便设计出较大焙烧带面积,有利于竖炉的大型化。 6、燃烧室、焙烧带、干燥带、防过湿带可分区独立计算机检测和控制,大大提高了操作精度,通过调试和操作可使各项参数达到最佳。

北师版高中英语翻译

Lesson 1 安格斯*伊德莱采访前百万富翁查尔斯雷时。查尔斯说:‘谁想当百万符文呢?我不想很多人一心想成为百万富翁。他们花一半的时间追求致富的方法。另一半的时间则在琢磨一旦富裕起来要做些什么。但是,是否所有的百万富翁真正得到了他们要实现的目标前所想的幸福呢、其实,有些人成为百万富翁后还有其他的烦恼———他们拼命的到的财富,怎样拼命以确保不在失去这些财富。 但是也有人把自己的百万资产置于一边,选择不同的人生的路,查二斯就是这样的一个人。 16年前,查尔斯是大学教授,住着一有六个卧室的房子,有着百万的资产,而现在住的则是小宿舍的房间,家具都是二手的,没有任何的迹象表明查尔斯是个富人没房间外有个小花园,花园里种着几个果树,查尔斯自己种植蔬菜和花,衣服和家具的用品都是从慈善点买的。 但是查尔斯喜欢折中改变。查尔斯对这样的富人的生活方式感到高兴。他不在想做在许多人一无所有的情况下自己拥有一切的那种人,他选择了了把自己的钱财送给别人,他说这样会给他带来快乐。 查尔斯说:几年前,我曾经是个百万富翁,但是我意识到世界上还有许多的忍受疾饿的穷人。因此他把所有的钱财捐给了慈善机构,当只剩下两千美元的时候,他将小额的纸币散发给当地的贫困街区的穷人,难道他真的举得自己像圣诞老人吗?查尔斯说这么做具有乐趣。 查尔斯相信很多人盼望着挣一大笔钱解除烦恼,然而,大多数的人根本没有挣多那么多的钱,查尔斯*格雷决定退出富人网,他发现拥有少量的钱会给人自由,难道真的没有什么让他依旧怀念的吗?查尔斯答道:没有,我现在更快乐了。什么也不可能在回到富人的行列——决不可能。 Lesson 3 五元钱能做什么?或许你觉得做不了什么,你如果对买包糖果或甜点不感兴趣的话,买课树怎样?确切的说,一棵树在黄河岸迹的树。 每年,大约有16亿吨泥土流入黄河——这条中国国第二大河流,这些泥土中含有保持该大自然平衡的物质,经年累月,大量的泥土被冲走,导致黄河两岸严重的水土流失,在山西省有些地区,折中水土流失几乎会掉了所有的土地,还迫使当地的农民迁移到其他地区去控制黄河水土流失是一项巨大的工程,很多人认为这项工作最好靠政府或是国际组织承担,你或许会赞同这样的观点,若真这样想的话,现在到了你重新考虑的时候了。 事实上,你才是阻止黄河水土流失最重要的人物,你知道你的五元钱的重要性吗?首先,你可以用五元钱买一棵树,而这棵树可以使泥土不流失,在肥沃的土地上,当地农民可以种庄稼陌生,农民会用他们种的庄稼赚到钱购买所需物品或服务,这有助于发展地区经济。 还是你不理解你得五元钱有如此大的作用吧?那么,看看下面的事实吧:自1997年期,一项植树计划已使内蒙古就成沙流变成了绿色家园,世界各地的人前来这里观赏这一伟大的成就,另外,这项规划的成功大大的改变了当地人民的生活,试想一下,这一切就是始于五元钱。 所以,下次当你的口袋里有五元钱时,仔细想想该怎么花,情记住,你可以用它买树,为了我们的祖国人民一及你自己创造绿色的未来。 所以,下次当你口袋里再有五元钱时,仔细想想该怎么花。请记住,你可以用它买树,为了我们的祖国,为人民以及你自己创造绿色的未来 Lesson 4 无线耳机

炼钢连铸工艺流程介绍

连铸工艺流程介绍 将高温钢水浇注到一个个的钢锭模内,而是将高温钢水连续不断地浇到一个或几个用强制水冷带有“活底”(叫引锭头)的铜模内(叫结晶器),钢水很快与“活底”凝结在一起,待钢水凝固成一定厚度的坯壳后,就从铜模的下端拉出“活底”,这样已凝固成一定厚度的铸坯就会连续地从水冷结晶器内被拉出来,在二次冷却区继续喷水冷却。带有液芯的铸坯,一边走一边凝固,直到完全凝固。待铸坯完全凝固后,用氧气切割机或剪切机把铸坯切成一定尺寸的钢坯。这种把高温钢水直接浇注成钢坯的新工艺,就叫连续铸钢。

【导读】:转炉生产出来的钢水经过精炼炉精炼以后,需要将钢水铸造成不同类型、不同规格的钢坯。连铸工段就是将精炼后的钢水连续铸造成钢坯的生产工序,主要设备包括回转台、中间包,结晶器、拉矫机等。本专题将详细介绍转炉(以及电炉)炼钢生产的工艺流程,主要工艺设备的工作原理以及控制要求等信息。由于时间的仓促和编辑水平有限,专题中难免出现遗漏或错误的地方,欢迎大家补充指正。? 连铸的目的: 将钢水铸造成钢坯。?将装有精炼好钢水的钢包运至回转台,回转台转动到浇注位置后,将钢水注入中间包,中间包再由水口将钢水分配到各个结晶器中去。结晶器是连铸机的核心设备之一,它使铸件成形并迅速凝固结晶。拉矫机与结晶振动装置共同作用,将结晶器内的铸件拉出,经冷却、电磁搅拌后,切割成一定长度的板坯。?连铸钢水的准备 一、连铸钢水的温度要求: 钢水温度过高的危害:①出结晶器坯壳薄,容易漏钢;②耐火材料侵蚀加快,易导致铸流失控,降低浇铸安全性;③增加非金属夹杂,影响板坯内在质量;④铸坯柱状晶发达;⑤中心偏析加重,易产生中心线裂纹。 钢水温度过低的危害:①容易发生水口堵塞,浇铸中断;②连铸表面容易产生结疱、夹渣、裂纹等缺陷; ③非金属夹杂不易上浮,影响铸坯内在质量。 二、钢水在钢包中的温度控制: 根据冶炼钢种严格控制出钢温度,使其在较窄的范围内变化;其次,要最大限度地减少从出钢、钢包中、钢包运送途中及进入中间包的整个过程中的温降。 实际生产中需采取在钢包内调整钢水温度的措施: 1)钢包吹氩调温 2)加废钢调温 3)在钢包中加热钢水技术 4)钢水包的保温 中间包钢水温度的控制

球团竖炉工国家职业标准

球团竖炉工国家职业标准 1.职业概况 1.1职业名称 球团竖炉工。 1.2职业定义 使用球团焙烧设备,对球团矿进行焙烧,以获得合格球团矿的人员。 1.3职业等级 本标准共设四个等级,分别为:初级(国家职业资格五级)、中级(国家职业资格四级)、高级(国家职业资格三级)、技师(国家职业资格二级)。 1.4职业环境条件 室内、外、高温、有毒有害。 1.5 职业能力特征 手指、手臂灵活,动作协调;学习能力、色觉和空间感强;无高温禁忌症。 1.6基本文化程度 高中毕业(或同等学历)。 1.7培训要求 1.7.1培训期限 全日制职业学校教育,根据其培养目标和教学计划确定。晋级培训期限:初级不少于400标准学时;中级不少于300标准学时;高级不少于200标准学时;技师不少于150标准学时。 1.7.2培训教师 培训初、中、高级的教师应具有本职业技师及以上职业资格证书或相关专业中级及以上专业技术职务任职资格;培训技师的教师应具有本职业技师资格证书2年以上或相关专业高级专业技术职务任职资格。 1.7.3培训场地设备 满足理论知识培训场地应具有可容纳20名以上学员,并配备投影仪、电视机及播放设备;满足实际操作培训用的焙烧设备、控制设备、取样工具及相关设备等。 1.8鉴定要求 1.8.1适用对象 从事或准备从事本职业的人员。 1.8.2申报条件 ——初级(具备以下条件之一者) (1)经本职业初级正规培训达到规定标准学时数,并取得结业证书。 (2)在本职业连续见习工作2年以上。 (3)在本职业学徒期满。 ——中级(具备以下条件之一者) (1)取得本职业初级职业资格证书后,连续从事本职业工作3年以上,经本职业中级正规培训达到规定标准学时数,并取得结业证书。 (2)取得本职业初级资格证书后,连续从事本职业5年以上。 (3)连续从事本职业7年以上。 (4)取得经劳动保障行政部门审核认定的、以中级技能为培养目标的中等以上职业学校本职业(专业)毕业证书。 ——高级(具备以下条件之一者) (1)取得本职业中级职业资格证书后,连续从事本职业工作4年以上,经本职业高级正规培训达到

北师大版高中英语模块一单词表

北师大版高中英语模块一单词表Unit 1 Learning to learn Questionnaire n. 问卷;调查表 matter n. 物质;原因;事件vi. 有关系;要紧partner n. 伙伴;合伙人;配偶 Warm-up lifestyle n. 生活方式 shepherd n. 牧羊人;牧师;指导者 peaceful adj. 和平的,爱好和平的;平静的relaxing adj. 令人轻松的推想 stressful adj. 紧张的;有压力的 suppose conj. 假使…结果会怎样vt. 假设;认为;Lesson 1 series n. 系列,连续;[电] 串联;丛书 TV series n. 电视连续剧 cartoon n. 卡通片,[电影] 动画片;连环漫画 talk show脱口秀;访谈节目 complain vi. Vt投诉;发牢骚;诉说 couch vi躺着n. 睡椅,长沙发 couch potato成天躺著或坐在沙发上看电视的人switch n. 开关;转换;鞭子vi. 转换;抽打 switch on接通,开启 switch off关掉;切断(电源) switch over切换转换交换 play n. 游戏;比赛;剧本 vt. 游戏;扮演;演奏;播放;同…比赛BBC(British Broadcasting Corporation) 英国广播公司portable adj. 手提的,便携式的;轻便的 remote adj. 遥远的;偏僻的;疏远的n. 远程remote control远程控制遥控器 workaholic工作狂专心工作的人拼命三郎paperwork n. 文书工作 alarm n. 警报,警告器;惊慌 alarm clock闹钟 go off离开;进行;变质;睡去爆炸动身 take up拿起;开始从事;占据(时间,地方) be filled with充满装满vt. 被……充满 urgent adj. 紧急的;急迫的 personal adj. 个人的;身体的;亲自的document文档文件公文midnight n. 午夜,adj. 半夜的;漆黑的 bored adj. 无聊的;无趣的;烦人的 Lesson 2 stress n. 压力;强调;紧张;重要性;重读 vt. 强调;使紧张;加压力于 studio n. 工作室制片厂画室 expert n. 专家;行家;能手adj. 熟练的; suffer vi. vt. 遭受;忍受 suffer from 忍受,遭受;患…病;受…之苦 pressure n. 压力;压迫,[物] 压强 social adj. 社会的,社交的;群居的 reduce vi. vt. 减少;降低;缩小; organize vi. 组织起来;成立组织 vt. 组织;使有系统化; diet饮食节食日常饮食 stand n. 站立;立场;看台;停止vi. 站立;位于;停滞vt. 使站立;忍受;抵抗 prefer vt. 更喜欢;宁愿;提出;提升 Lesson 3 volunteer n. 志愿者;志愿兵adj. 志愿的vt. vi. 自愿graduate毕业生毕业研究生vi. 毕业;渐变 minus prep. 减,减去 n. 负号,减号;不足;负数 basin 盆地流域洗脸盆 challenge n. 挑战;怀疑vt. 向…挑战 support n. 支持;支援,供养;支持者,支撑物 vt. 支持,支撑;扶持,;赡养,供养 dial刻度盘拨号拨 design n. 设计;图案vt. 设计;计划;构思advertisement n. 广告,宣传 presentation n. 描述,陈述;介绍;赠送 solve解决解答求解 Lesson 4 accountant n. 会计师;会计人员 tube n. 管;电子管;隧道;电视机 crowded adj. 拥挤的;塞满的 nearby prep. 在…附近adj. 附近的,邻近的adv. 在附近otherwise adv. 否则;另外;在其他方面 forecast n. 预测,预报vt. vi预报,预测;预示.

炼钢工艺流程

【导读】:转炉炼钢是把氧气鼓入熔融的生铁里,使杂质硅、锰等氧化。在氧化的过程中放出大量的热量(含1%的硅可使生铁的温度升高200摄氏度),可使炉内达到足够高的温度。因此转炉炼钢不需要另外使用燃料。炼钢的基本任务是脱碳、脱磷、脱硫、脱氧,去除有害气体和非金属夹杂物,提高温度和调整成分。归纳为:“四脱”(碳、氧、磷和硫),“二去”(去气和去夹杂),“二调整”(成分和温度)。采用的主要技术手段为:供氧,造渣,升温,加脱氧剂和合金化操作。本专题将详细介绍转炉炼钢生产的工艺流程,主要工艺设备的工作原理以及控制要求等信息。由于时间的仓促和编辑水平有限,专题中难免出现遗漏或错误的地方,欢迎大家补充指正。 转炉冶炼目的:将生铁里的碳及其它杂质(如:硅、锰)等氧化,产出比铁的物理、化学性能与力学性能更好的钢。 【相关信息】钢与生铁的区别:首先是碳的含量,理论上一般把碳含量小于2.11%称之钢,它的熔点在1450-1500℃,而生铁的熔点在1100-1200℃。在钢中碳元素和铁元素形成Fe3C固熔体,随着碳含量的增加,其强度、硬度增加,而塑性和冲击韧性降低。钢具有很好的物理、化学性能与力学性能,可进行拉、压、轧、冲、拔等深加工,其用途十分广泛。 转炉冶炼原理简介: 转炉炼钢是在转炉里进行。转炉的外形就像个梨,内壁有耐火砖,炉侧有许多小孔(风口),压缩空气从这些小孔里吹炉内,又叫做侧吹转炉。开始时,转炉处于水平,向内注入1300摄氏度的液态生铁,并加入一定量的生石灰,然后鼓入空气并转动转炉使它直立起来。这时液态生铁表面剧烈的反应,使铁、硅、锰氧化 (FeO,SiO2 , MnO,) 生成炉渣,利用熔化的钢铁和炉渣的对流作用,使反应遍及整个炉内。几分钟后,当钢液中只剩下少量的硅与锰时,碳开始氧化,生成一氧化碳(放热)使钢液剧烈沸腾。炉口由于溢出的一氧化炭的燃烧而出现巨大的火焰。最后,磷也发生氧化并进一步生成磷酸亚铁。磷酸亚铁再跟生石灰反应生成稳定的磷酸钙和硫化钙,一起成为炉渣。当磷与硫逐渐减少,火焰退落,炉口出现四氧化三铁的褐色蒸汽时,表明钢已炼成。这时应立即停止鼓风,并把转炉转到水平位置,把钢水倾至钢水包里,再加脱氧剂进行脱氧。整个过程只需15分钟左右。如果氧气是从炉底吹入,那就是底吹转炉;氧气从顶部吹入,就是顶吹转炉。 转炉冶炼工艺流程简介:

球团竖炉工艺介绍

12㎡×2球团竖炉工艺介绍 一.配料工艺介绍: 1.配料料仓布局,膨润土(1#和2#仓)铁精粉(3#-7#仓)由东向西一字排列。 2.原料入仓方式,袋装膨润土使用小型电动吊车起吊至料仓上方,包装袋下部开口,膨润土直接装入料仓。吊车配备电子吊钩称,在起吊入仓时分别对每袋膨润土计量并记录,每班汇总数量上报厂部;铁精粉使用装载机车辆运输入仓。 3.原料计量方式,配料室每个料仓下料口配备圆盘给料机和电子计量皮带秤,按照配比调整出料量,并记录数值。 4.原料经过配料皮带机输送到烘干混合机。 二.烘干混合工艺介绍: 1.混合的目的,使不同种类原料水分、粒度、成分等指标充分混合,得到均一稳定的造球原料。 2.烘干的目的,原料进场水份高低不同,为稳定造球原料水分在(7.5±0.5%)区间,使用烘干炉煤气与空气混合燃烧产生高温烘干气体,控制调整混合料水分。 3.烘干混合后的原料经过烘干皮带机输送到造球室。 三.造球工艺介绍: 1.设备布局,1#,2#造球室分别对应1#,2#竖炉。1#,2#造球室各3个造球盘,每个造球盘上方对应混合料仓和给料皮带。 2.造球原理,铁精粉被水润湿在滚动过程中靠毛细引力、分子引力、摩擦力等作用形成一定粒度的生球,并使生球具有一定强度能够入炉焙烧。 3.生球团经过生球皮带机输送到辊式筛分机。 四.辊式筛分机介绍: 1.筛分原理,通过调整相临圆辊之间的距离,把整个筛分机辊面分成Ф<9mm,9-16mm和>16mm三个区域。生球经过筛面时不同直径的生球被筛分三级,Ф9-16mm粒级入炉焙烧,Ф<9mm和>16mm粒级不合格生球由返料皮带机输送返回造球室。(粒级区间可按实际生产调整) 2.合格生球经过生球皮带机输送到竖炉布料。 五.竖炉焙烧工艺介绍: 1.布料工艺,合格生球通过往复梭式布料车均匀铺在“人”字型烘干床上。 2.焙烧工艺,生球由炉顶向下经过烘干→预热→焙烧→均热→冷却过程。 3.红热球团由振动卸料机和链板机输送到带式冷却机。 六.成品冷却系统介绍: 1.带式冷却机,台车底部为通风篦板,按冷却需求开启4台鼓风机。带冷机排矿温度≤150℃。 2.成品球团经过成品皮带机输送至高炉或汽运落地库存。 七.脱硫系统介绍: 1.脱硫原理,制备消石灰CaO+H 2O→Ca(OH) 2 烟气脱硫SO 2+Ca(OH) 2 →CaSO 3 +H 2 O 2.系统流程,烟气→电除尘→风机→石灰浆液逆流喷淋→浆液真空过滤→脱硫石膏排出。

相关主题
相关文档 最新文档