Zobrazeno 1 - 10
of 183
pro vyhledávání: '"S.A. Abo El-Enein"'
Publikováno v:
HBRC Journal, Vol 14, Iss 2, Pp 207-214 (2018)
A number of chemical and mineral admixtures are usually used in the oil-well cement (OWC) pastes to modify and control their fluidity to resist the higher temperatures and pressures during the drilling process of the well. In this study a newly prepa
Externí odkaz:
https://doaj.org/article/a69b896247954f0cba8e2fa6fbf953a4
Autor:
H.A. Abdel-Gawwad, S.A. Abo-El-Enein
Publikováno v:
HBRC Journal, Vol 12, Iss 1, Pp 13-24 (2016)
Geopolymer cement is the result of reaction of two materials containing aluminosilicate and concentrated alkaline solution to produce an inorganic polymer binder. The alkali solutions are corrosive and often viscous solutions which are not user frien
Externí odkaz:
https://doaj.org/article/0bbfc0bb6d1744f29e064d475cf54f8d
Publikováno v:
HBRC Journal, Vol 11, Iss 3, Pp 321-327 (2015)
Filled-pozzolanic cement pastes were made by different replacements of OPC by electric arc furnace slag (EAFS) with silica fume (SF) at water/cement ratio of 0.27. The pastes were hydrated up to 90 days. At each time interval, the physico-chemical ch
Externí odkaz:
https://doaj.org/article/6b00db2832cd478b8988a40c425261e1
Publikováno v:
HBRC Journal, Vol 11, Iss 1, Pp 7-15 (2015)
This works aims to study the effect of partial substitution of ordinary Portland cement (OPC) by silica fume (SF) and fly ash (FA) on the physico-mechanical properties of the hardened OPC–FA–SF composite cement pastes. The OPC was partially repla
Externí odkaz:
https://doaj.org/article/e3a856771dc8423391e37434d304705d
Publikováno v:
HBRC Journal, Vol 10, Iss 1, Pp 64-72 (2014)
Nano-metakaolin (NMK) was prepared by firing of Nano-kaolin (NK) at different temperatures (750–825 °C) for 2 h. The pozzolanic activities of NMK samples were studied using hydrated lime as an activator. The optimum firing temperature of metakaoli
Externí odkaz:
https://doaj.org/article/b4473a2b8cd24456baf5ece596785c65
Publikováno v:
HBRC Journal, Vol 9, Iss 2, Pp 118-124 (2013)
Utilization of electric arc furnace slag (EAF slag) as blending material for Portland cement has been examined. This was done via the investigation of the hydration characteristic of EAF slag – Portland cement blended mixtures. Various ratios of EA
Externí odkaz:
https://doaj.org/article/ce3c4bbc75b94242a28964ca019da3db
Publikováno v:
HBRC Journal, Vol 9, Iss 1, Pp 36-40 (2013)
Calcite is one of the most common and wide spread mineral on Earth constituting 4 wt% of the Earth’s crust. It is naturally found in extensive sedimentary rock masses, as lime stone marble and calcareous sandstone in marine, fresh water and terrest
Externí odkaz:
https://doaj.org/article/e916095f1df54eb8afdade3d7c0f2be6
Publikováno v:
HBRC Journal, Vol 8, Iss 3, Pp 185-192 (2012)
The microbes can hydrolyze urea by urease enzyme to produce ammonium as well as carbonate ions and in the presence of calcium ions which can precipitate calcium carbonate; this process is called “biocalcification” or microbial induced calcite pre
Externí odkaz:
https://doaj.org/article/a1f43d7635d742eca2dadba369dbe146
Publikováno v:
Arabian Journal of Chemistry, Vol 9, Iss S1, Pp S138-S143 (2016)
This investigation dealt with the effect of active silica, silica fume (SF) or rice husk ash (RHA), on the mechanical and physico-chemical characteristics of the hardened blended cement pastes made of Portland blast-furnace slag cement (PSC) containi
Externí odkaz:
https://doaj.org/article/23d5c07087124792b4cf20f81f26e7a4
Autor:
A.M. Saad, Abdul-Basit A. Saleh, Fatima A. Al-Kadri, Abdulla S. Babaqi, Abdulla A. Basissa, S.A. Abo El-Enein
Publikováno v:
Sultan Qaboos University Journal for Science, Vol 13, Iss 0, Pp 13-25 (2008)
Portland cement pastes of various porosities were prepared using water/cement ratios of 0.30, 0.35, 0.40, 0.45, 0.50 and 0.55; and were hydrated for various time intervals ranging from 0.021 to 28 days. Pore structure and VL–t plots (plots of volum
Externí odkaz:
https://doaj.org/article/9ba61fb7789540a6a4b9e78a851ae7bb