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111.
Synthesis of new colloidal formations during the strengthening of different activated hydrated metallurgical slags 总被引:3,自引:0,他引:3
Vsvolod A. Mymrin Haroldo A. Ponte Carlos I. Yamamoto 《Colloids and surfaces. A, Physicochemical and engineering aspects》2003,220(1-3):211-221
This paper reports on a comparison of experimental researches on the hydration hardening of different types of dumped ferrous slag (DFS) (blast furnace, open hearth, electric steel and converter), non-activated and activated with small (2%) additions of Portland cement or lime. Activation was found to accelerate the strengthening processes in the early stages of hydration resulting from the growth of colloidal sol–gel new formations in a more alkaline environment. Over time, these formations became denser and transformed into stone-like amorphous materials with a uniaxial strength of up to 47.6 MPa at 1 year of age. All these types of slag can, therefore, be used in different applications, for example, like traditional binders, such as Portland cement, to different ceramic goods, new construction materials, etc. But till now the results of this research were used only for the preparing of binder materials for natural soils strengthening as road bases in Russia. Highways whose roadbeds were built with these DFS as binder materials have shown excellent performance indices in different parts of Russia, including Siberia and northern regions. 相似文献
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Takakazu Yamamoto Junichi Ishizu Sanshiro Komiya Yoshiyuki Nakamura Akio Yamamoto 《Journal of organometallic chemistry》1979,171(1):103-112
13C NMR data are given for a series of phosphinenickel(0) complexes of ethyl methacrylate (ema), Ni(PR3)2(CH2=C(CH3)COOC2H5) (PR3 = PPh3 (Ia), PEtPh2 (Ib), PEt2Ph (Ic), PMe2Ph (Id), PEt3 (Ie)). The olefinic carbon signals of ema shift upfield by 71.5–86.5 ppm on coordination, the magnitude of the upfield shift increasing with increase in the bacisity of the phosphine ligand. The effect of the basicity of PR3 is discussed on the basis of the back-bonding from Ni to ema. Variable temperature1H NMR studies reveal that the ema of Id, the complex having the least sterically demanding phosphine ligands, exchanges with free ema in toluene on the NMR time scale. The dependence of the rate of exchange on the concentration of ema shows that the exchange proceeds through anSN2 mechanism. The activation parameters are: ΔH273≠ 2.75 kcal/mol, ΔG273≠ 12.7 kcal/mol, ΔS273≠ ?37 e.u. The31P NMR spectra of the complexes show two doublets when the exchange is frozen out, indicating the inequivalence of the two phosphine ligands in the ema-coordinated complex. The difference in the31P chemical shifts of the two coordinated tertiary phosphines increases with increase in the basicity of the PR3 ligand. 相似文献
114.
Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C 《Physical review letters》1995,75(21):3809-3813
115.
Balakin V Alexandrov VA Mikhailichenko A Flöttmann K Peters F Voss G Bharadwaj V Halling M Holt JA Buon J Jeanjean J LeDiberder F Lepeltier V Puzo P Heimlinger G Settles R Stierlin U Hayano H Ishihara N Nakayama H Oide K Shintake T Takeuchi Y Yamamoto N Bulos F Burke D Field R Hartman S Helm R Irwin J Iverson R Rokni S Roy G Spence W Tenenbaum P Wagner SR Walz D Williams S 《Physical review letters》1995,74(13):2479-2482
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Cinabro D Henderson S Liu T Saulnier M Wilson R Yamamoto H Bergfeld T Eisenstein BI Gollin G Ong B Palmer M Selen M Thaler JJ Sadoff AJ Ammar R Ball S Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kwak N Lam H Kubota Y Lattery M Nelson JK Patton S Perticone D Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Nemati B O'Neill JJ Severini H Sun CR Zoeller MM Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Malchow R Morrow F Skovpen Y 《Physical review letters》1994,72(10):1406-1410
120.
Balest R Cho K Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Drell PS Ehrlich R Gaiderev P Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Salman S Sapper M Würthwein F Avery P Freyberger A Rodriguez J Stephens R Yang S Yelton J 《Physical review letters》1994,72(15):2328-2331