NO874075L - Silisiumdioksyd oppslemming. - Google Patents
Silisiumdioksyd oppslemming.Info
- Publication number
- NO874075L NO874075L NO874075A NO874075A NO874075L NO 874075 L NO874075 L NO 874075L NO 874075 A NO874075 A NO 874075A NO 874075 A NO874075 A NO 874075A NO 874075 L NO874075 L NO 874075L
- Authority
- NO
- Norway
- Prior art keywords
- silica dust
- cement
- dispersion
- additive according
- viscosity
- Prior art date
Links
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims description 83
- 239000000377 silicon dioxide Substances 0.000 title description 8
- 235000012239 silicon dioxide Nutrition 0.000 title description 8
- 239000000725 suspension Substances 0.000 title 1
- 239000006185 dispersion Substances 0.000 claims description 65
- 239000000203 mixture Substances 0.000 claims description 35
- 239000004568 cement Substances 0.000 claims description 28
- 238000004519 manufacturing process Methods 0.000 claims description 26
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 12
- 239000011734 sodium Substances 0.000 claims description 12
- 239000006227 byproduct Substances 0.000 claims description 11
- 229910000519 Ferrosilicon Inorganic materials 0.000 claims description 10
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 10
- 239000000654 additive Substances 0.000 claims description 10
- 230000000996 additive effect Effects 0.000 claims description 10
- 229910052783 alkali metal Inorganic materials 0.000 claims description 10
- 150000001340 alkali metals Chemical class 0.000 claims description 10
- 229920000058 polyacrylate Polymers 0.000 claims description 10
- 229910052708 sodium Inorganic materials 0.000 claims description 10
- 239000003795 chemical substances by application Substances 0.000 claims description 7
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 6
- 229910052700 potassium Inorganic materials 0.000 claims description 6
- 239000003381 stabilizer Substances 0.000 claims description 6
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 5
- 239000011591 potassium Substances 0.000 claims description 5
- 159000000001 potassium salts Chemical class 0.000 claims description 4
- 229920002153 Hydroxypropyl cellulose Polymers 0.000 claims description 3
- 150000007513 acids Chemical class 0.000 claims description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 3
- 239000011396 hydraulic cement Substances 0.000 claims description 3
- 239000001863 hydroxypropyl cellulose Substances 0.000 claims description 3
- 159000000000 sodium salts Chemical group 0.000 claims description 3
- 229920002134 Carboxymethyl cellulose Polymers 0.000 claims description 2
- 229920002125 Sokalan® Polymers 0.000 claims description 2
- 239000001768 carboxy methyl cellulose Substances 0.000 claims description 2
- 235000010948 carboxy methyl cellulose Nutrition 0.000 claims description 2
- 125000004181 carboxyalkyl group Chemical group 0.000 claims description 2
- 239000008112 carboxymethyl-cellulose Substances 0.000 claims description 2
- 239000001913 cellulose Substances 0.000 claims description 2
- 229920002678 cellulose Polymers 0.000 claims description 2
- 229920013821 hydroxy alkyl cellulose Polymers 0.000 claims description 2
- 235000010977 hydroxypropyl cellulose Nutrition 0.000 claims description 2
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 2
- 229920000233 poly(alkylene oxides) Polymers 0.000 claims description 2
- 239000004584 polyacrylic acid Substances 0.000 claims description 2
- 235000019832 sodium triphosphate Nutrition 0.000 claims description 2
- 229920002845 Poly(methacrylic acid) Polymers 0.000 claims 1
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 claims 1
- UNXRWKVEANCORM-UHFFFAOYSA-I triphosphate(5-) Chemical compound [O-]P([O-])(=O)OP([O-])(=O)OP([O-])([O-])=O UNXRWKVEANCORM-UHFFFAOYSA-I 0.000 claims 1
- 239000007788 liquid Substances 0.000 description 14
- 239000000463 material Substances 0.000 description 13
- 239000000047 product Substances 0.000 description 8
- 150000003839 salts Chemical class 0.000 description 7
- 229910052710 silicon Inorganic materials 0.000 description 7
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 239000003638 chemical reducing agent Substances 0.000 description 6
- 239000010703 silicon Substances 0.000 description 6
- 238000003860 storage Methods 0.000 description 6
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 5
- 229920001577 copolymer Polymers 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 229910021487 silica fume Inorganic materials 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical group CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000010891 electric arc Methods 0.000 description 3
- 229920001495 poly(sodium acrylate) polymer Polymers 0.000 description 3
- 229920000193 polymethacrylate Polymers 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- NNMHYFLPFNGQFZ-UHFFFAOYSA-M sodium polyacrylate Chemical compound [Na+].[O-]C(=O)C=C NNMHYFLPFNGQFZ-UHFFFAOYSA-M 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 229920001732 Lignosulfonate Polymers 0.000 description 2
- 150000001768 cations Chemical class 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- -1 ferrosilicon alloys Chemical compound 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229920001519 homopolymer Polymers 0.000 description 2
- 239000012263 liquid product Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 239000002562 thickening agent Substances 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- SQAINHDHICKHLX-UHFFFAOYSA-N 1-naphthaldehyde Chemical compound C1=CC=C2C(C=O)=CC=CC2=C1 SQAINHDHICKHLX-UHFFFAOYSA-N 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical group [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 1
- 229920000388 Polyphosphate Polymers 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- 229910000676 Si alloy Inorganic materials 0.000 description 1
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- 230000000740 bleeding effect Effects 0.000 description 1
- 150000001720 carbohydrates Chemical class 0.000 description 1
- 235000014633 carbohydrates Nutrition 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 229920003086 cellulose ether Polymers 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000010961 commercial manufacture process Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000004567 concrete Substances 0.000 description 1
- 239000013256 coordination polymer Substances 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 230000009969 flowable effect Effects 0.000 description 1
- 238000001879 gelation Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052745 lead Inorganic materials 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000007974 melamines Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 150000002790 naphthalenes Chemical class 0.000 description 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000001205 polyphosphate Substances 0.000 description 1
- 235000011176 polyphosphates Nutrition 0.000 description 1
- 229920005614 potassium polyacrylate Polymers 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000002210 silicon-based material Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 235000000346 sugar Nutrition 0.000 description 1
- 150000008163 sugars Chemical class 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 150000003751 zinc Chemical class 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/14—Waste materials; Refuse from metallurgical processes
- C04B18/146—Silica fume
- C04B18/147—Conditioning
- C04B18/148—Preparing silica fume slurries or suspensions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Civil Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- Silicon Compounds (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US91201986A | 1986-09-29 | 1986-09-29 | |
| US06/912,018 US4888058A (en) | 1986-09-29 | 1986-09-29 | Silica fume slurry |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| NO874075D0 NO874075D0 (no) | 1987-09-28 |
| NO874075L true NO874075L (no) | 1988-03-30 |
Family
ID=27129592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO874075A NO874075L (no) | 1986-09-29 | 1987-09-28 | Silisiumdioksyd oppslemming. |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0263606A3 (da) |
| JP (1) | JPH0816019B2 (da) |
| AU (1) | AU594812B2 (da) |
| CA (1) | CA1272742A (da) |
| DK (1) | DK509087A (da) |
| NO (1) | NO874075L (da) |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0269015A3 (en) * | 1986-11-21 | 1989-03-01 | HENKEL CORPORATION (a Delaware corp.) | Sag resistant dry set mortar composition |
| NO162848C (no) * | 1987-09-11 | 1990-02-28 | Elkem As | Fremgangsmaate for tilsetning av silica stoev til en toerr sproeyte-betongblanding. |
| GB8904273D0 (en) * | 1989-02-24 | 1989-04-12 | Sandoz Ltd | Improvements in or relating to chemical compounds |
| GB2241499B (en) * | 1990-03-03 | 1994-09-21 | Sandoz Ltd | Concrete spraying process |
| GB9903938D0 (en) * | 1999-02-22 | 1999-04-14 | Univ Keele | Cementitious compositions |
| JP4959185B2 (ja) * | 2005-12-14 | 2012-06-20 | 住友大阪セメント株式会社 | シリカフュームスラリー |
| JP4895693B2 (ja) * | 2006-06-06 | 2012-03-14 | 住友大阪セメント株式会社 | コンクリートの製造方法及びコンクリート |
| JP4837483B2 (ja) * | 2006-08-04 | 2011-12-14 | 住友大阪セメント株式会社 | 高強度コンクリート用シリカフュームスラリー |
| JP4976803B2 (ja) * | 2006-10-13 | 2012-07-18 | 電気化学工業株式会社 | グラウト組成物およびそれを用いたグラウト材料 |
| JP5189274B2 (ja) * | 2006-11-10 | 2013-04-24 | 電気化学工業株式会社 | 地盤注入材及びそれを用いた地盤注入工法 |
| US8759423B2 (en) * | 2012-04-20 | 2014-06-24 | W. R. Grace & Co.-Conn. | Stabilized defoamers for cementitious compositions |
| US9994484B2 (en) | 2013-07-30 | 2018-06-12 | United States Gypsym Company | Fast setting portland cement compositions with alkali metal citrates and phosphates with high early-age compressive strength and reduced shrinkage |
| CN105130307A (zh) * | 2015-08-29 | 2015-12-09 | 华南理工大学 | 一种高流动性硅灰浆的制备方法 |
| US20220081364A1 (en) * | 2019-01-10 | 2022-03-17 | Construction Research & Technology Gmbh | Additive and admixture for cementitious compositions, cementitious compositions, cementitious structures and methods of making the same |
| US20220098120A1 (en) * | 2019-01-10 | 2022-03-31 | Construction Research & Technology Gmbh | Method of stabilizing an admixture component, a stabilized admixture for cementitious compositions, cementitious composition, cementitious structures and methods of making the same |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2510224A1 (de) * | 1974-03-14 | 1975-09-25 | Alfong Betonhaerdningsmedel & | Verfahren und zusatzmittel zur herstellung von betongegenstaenden |
| NO153566B (no) * | 1982-12-07 | 1986-01-06 | Elkem As | Tilsetningsblanding for betong og moertel, fremgangsmaate til fremstilling av blandingen, samt anvendelse derav. |
-
1987
- 1987-09-15 EP EP19870308153 patent/EP0263606A3/en not_active Withdrawn
- 1987-09-23 CA CA000547669A patent/CA1272742A/en not_active Expired - Lifetime
- 1987-09-23 AU AU78882/87A patent/AU594812B2/en not_active Ceased
- 1987-09-28 JP JP24100887A patent/JPH0816019B2/ja not_active Expired - Lifetime
- 1987-09-28 NO NO874075A patent/NO874075L/no unknown
- 1987-09-28 DK DK509087A patent/DK509087A/da not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| DK509087A (da) | 1988-03-30 |
| DK509087D0 (da) | 1987-09-28 |
| AU7888287A (en) | 1988-03-31 |
| EP0263606A3 (en) | 1988-08-31 |
| CA1272742A (en) | 1990-08-14 |
| JPS63147849A (ja) | 1988-06-20 |
| EP0263606A2 (en) | 1988-04-13 |
| JPH0816019B2 (ja) | 1996-02-21 |
| AU594812B2 (en) | 1990-03-15 |
| NO874075D0 (no) | 1987-09-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| NO874075L (no) | Silisiumdioksyd oppslemming. | |
| CN107473685B (zh) | 一种氟石膏基内墙抹灰材料及其生产工艺 | |
| CA2229020C (en) | High solids lime as a caustic replacement | |
| US4888058A (en) | Silica fume slurry | |
| SE460288B (sv) | Tillsatsblandning foer betong och bruk, foerfarande foer dess framstaellning samt anvaendning av densamma | |
| HU206300B (en) | Process for chemical stabilizing heavy metal-containing contaminations and precipitations | |
| GB2132599A (en) | Corrosion inhibiting additive for cement compositions | |
| US3923717A (en) | A kiln feed slurry for making portland cement containing an inorganic slat of a styrene-maleic anhydride copolymer | |
| NO20101299A1 (no) | Slurry av manganomanganioksidpartikler og fremgangsmate for fremstilling av slik slurry | |
| CA2975415A1 (en) | Liquid coloring suspension and colored cementitious composition | |
| JPH07100606B2 (ja) | ミクロシリカスラリ−及びその製造方法 | |
| JPH02248350A (ja) | 改良されたポゾラン組成物 | |
| NO342672B1 (en) | Microsilica slurry and method for producing such slurry | |
| CN111747665B (zh) | 一种添加拜耳法赤泥的成品水泥制作工艺 | |
| JPH058136B2 (da) | ||
| JP2672004B2 (ja) | シリカヒユームスラリー | |
| CN108659175A (zh) | 一种制备聚羧酸减水剂的方法和一种缓凝剂及其制备方法 | |
| CN109320118B (zh) | 一种干喷或者潮喷混凝土纳米级掺合料及其使用方法 | |
| US4046581A (en) | Refractory binder | |
| CN108659174A (zh) | 一种制备聚羧酸减水剂的方法和一种缓凝剂及其制备方法 | |
| US4226635A (en) | Extended BaCO3 for brick scum prevention | |
| US4755226A (en) | Sealing and/or stabilizing and/or binding preparations comprising alkali metal silicate solutions | |
| US5207997A (en) | Process for producing an inorganic barium-containing solids composition | |
| US1282188A (en) | Oxysalt composition and process of making the same. | |
| JPS6144835B2 (da) |