scholarly journals EFEKTIVITAS SUPERPLASTICIZER TERHADAP WORKABILITAS DAN KUAT TEKAN BETON GEOPOLIMER

2019 ◽  
Vol 10 (2) ◽  
Author(s):  
Herwani Herwani ◽  
Iswandi Imran ◽  
Ivindra Pane ◽  
Ediansjah Zulkifli ◽  
Elvira Elvira
Keyword(s):  
Fly Ash ◽  
M 10 ◽  
M 12

Beton Geopolimer merupakan beton yang tersusun dari campuran agregat kasar dan halus tanpa pengikat semen Portland (OPC). Sebagai penggantinya, digunakan pengikat dari bahan yang banyak mengandung silica dan alumina seperti fly ash. Analog dengan beton yang berbasis semen Portland, beton geopolimer juga menjadi kurang sempurna jika campuran beton segar mempunyai konsistensi yang tinggi dan bersifat kental (kaku) sehingga sulit untuk dikerjakan (workabilitas rendah). Penambahan Superplastisizer manjadi salah satu cara untuk meningkatkan workabilitasnya. Dalam makalah ini digunakan superplastisizer yang berbasis naphthalene dengan dosis 0%, 1.5%, dan 2 %. Molaritas larutan NaOH yang digunakan sebagai aktivator alkalin adalah 8 M, 10 M, 12 M, dan 14 M dengan rasio Na2SiO3/NaOH = 1.5. Dari hasil pengujian diketahui bahwa pengaruh superplastisizer yang berbasis naphthalene cukup efektif untuk memperbaiki workabilitas beton geopolymer. Beton segar menjadi lebih encer dan mudah dilakukan pemadatan saat di tuang ke dalam cetakan. Superplastisizer juga mampu meningkatkan kekuatan beton geopolymer namun besaran hanya mencapai 5.42%. Dosis Superplastisizer akan optimum pada persentase 1.5% terhadap berat fly ash dengan kuat tekan mencapai 31.63 MPa dan nilai slump antara 8-10 cm. Molaritas larutan NaOH yang baik untuk rasio Na2SiO3/NaOH = 1.5 adalah 8 M.

scholarly journals Fly ASH Aggregates on Strength and Workability Characters of Geo-Polymer Concrete

2019 ◽  
Vol 8 (12S) ◽  
pp. 957-962
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Strength Test ◽  
Polymer Concrete ◽  
M 10 ◽  
The Matrix ◽  
Naoh Solution ◽  
M 12 ◽  
Maximum Compressive Strength ◽  
Ash Aggregates

The Present study deals with preparation of FA aggregates. Artificial aggregates with FA (class C) and combination of fly ash and GGBFS were preparedTwo sorts of restoring techniques were embraced for aggregates. Restoring strategies incorporate water relieving and Chemical restoring (NaoH). The tests results the fly ash water cured and chemically cured aggregates were performed well, so these two types of aggregates were adopted for preparation of GPC mixes. The GGBFS replacement content in finalized as 30% from phase I results. The GPC mixes with 8 M, 10 M, 12 M NaoH Solution concentrations were cast using fly ash aggregates. Workability and strength test were done on the GPC samples. It was observed that GPC mix W6 attained a maximum compressive strength of 42.89 MPa among GPC specimens with water cured aggregates. It is observed that the specimens with chemically cured aggregates. It is observed that the GPC mix with chemical cured aggregate have better workability and bonding with the matrix

scholarly journals Photometry of Faint Stars in Globular Clusters using the Six Meter Telescope

1988 ◽  
Vol 126 ◽  
pp. 619-620
Author(s):  
N. Samus
Keyword(s):  
Globular Clusters ◽  
Horizontal Branch ◽  
Group V ◽  
M 10 ◽  
Group I ◽  
Ubv Photometry ◽  
M 12 ◽  
Magnitude Difference ◽  
Photographic Photometry ◽  
Branch Morphology

Our program is based on photographic and photoelectric UBV photometry of globular cluster stars with the Soviet 6 m telescope. M 10 = NGC 6254 remains, regretfully, the only cluster for which we were able to gain photoelectric observational material sufficient for calibration of the photographic photometry for faint stars. Samus and Shugarov (1983) presented for M 10 a V, (B - V) diagram showing an unusually large magnitude difference between the main sequence turn-off point and the horizontal branch, V(TO) - V(HB) ≍ 3.8 mag. It seemed of interest to compare M 10 and M 12 by their values of V(TO) - V(HB). A preliminary calibration of the faint star photographic photometry in M 12 leads to V(TO) - V(HB) ≍ 4 mag (Mironov et al., 1984). One may notice that in the classification introduced by Mironov and Samus (1974, 79), which is based mainly on the horizontal-branch morphology, both M 10 and M 12 belong to group I, presumably the older group. V, (B-V) diagrams were also published by us for NGC 288 and M 2 = NGC 7089 (Samus and Shugarov 1978, 79).

The chemical composition of stars in the globular clusters M 10, M 12, and M 71

2003 ◽  
Vol 47 (3) ◽  
pp. 248-253 ◽  
Author(s):  
T. V. Mishenina ◽  
V. E. Panchuk ◽  
N. N. Samus’
Keyword(s):  
Chemical Composition ◽  
Globular Clusters ◽  
M 10 ◽  
M 12

scholarly journals The assessment of Ki-67 as a prognostic marker in neuroendocrine tumours: a systematic review and meta-analysis

2015 ◽  
Vol 69 (7) ◽  
pp. 612-618 ◽  
Author(s):  
Sebastian Richards-Taylor ◽  
Sean M Ewings ◽  
Eleanor Jaynes ◽  
Charles Tilley ◽  
Sarah G Ellis ◽  
...  
Keyword(s):  
English Language ◽  
Neuroendocrine Tumours ◽  
Meta Analysis ◽  
Survival Rates ◽  
Combine Data ◽  
Exclusion Criteria ◽  
Ki 67 ◽  
M 10 ◽  
M 12 ◽  
Gastroenteropancreatic Neuroendocrine Tumours

IntroductionGastroenteropancreatic neuroendocrine tumours (GEP NETs) are classified according to tumour mitotic count or Ki-67 labelling index (LI).Aim(s)To systematically review articles reporting the prognosis of patients by Ki-67 LI and thereby improve the ability of clinicians to prognosticate for their patients.Method265 abstracts were identified relating Ki-67 and survival. After exclusion criteria were applied, 22 articles remained. Articles were excluded if they described non-human specimens, were non-English language, published prior to 2000, reported non-GEP NETs, reported subgroups selected by treatment modality or included <20 cases. Random-effects meta-analysis was used to combine studies to estimate survival proportions.ResultsAuthors used varied methods in which to present 5-year survival, with often limited survival information. This reduced the number of studies that could be included in the meta-analysis. 5-year survival for patients with grade 1 and 2 GEP NETs were estimated to be 89% (95% CI 85% to 92%, m=12 studies, n=977 participants) and 70% (95% CI 62% to 79%, m=9, n=726), respectively. Using an alternative grade 1/2 boundary of 5%, 5-year survival rates for Ki-67≤5% and 5–20% were estimated as 89% (95% CI 84% to 94%, m=7, n=654) and 51% (95% CI 44% to 59%, m=4, n=183), respectively. For Ki-67>20%, 5-year survival was estimated to be 25% (95% CI 12% to 38%, m=10, n=208).ConclusionsStandardisation of grade boundaries has allowed us to combine data from multiple studies and amass a body of evidence linking Ki-67 and survival.

Algorithm and Experiment of the Separated Foundation Bearing Capacity of Culverts Considering Lateral Fill

2012 ◽  
Vol 450-451 ◽  
pp. 1616-1624
Author(s):  
Wen Lu Wang ◽  
Shu Jun Cui ◽  
Da Jun Zhao ◽  
Lei Wang
Keyword(s):  
Bearing Capacity ◽  
Model Test ◽  
Similarity Theory ◽  
Calculation Model ◽  
Test Results ◽  
Foundation Soil ◽  
Model Experiments ◽  
M 10 ◽  
Foundation Deformation ◽  
M 12

How to determine the foundation bearing capacity of high-stacked culverts in highway construction becomes a problem that must be taken seriously. Combining with the stress characteristics of the foundation soil, the soil force was analyzed for finding the improved effect on the separated foundation bearing capacity of lateral fill. Establishing the calculation model and algorithm, the general formulation of separated foundation bearing capacity considering lateral fill was deduced. Then under direction of similarity theory, six model experiments were designed to simulate the silt clay foundation deformation in whole loading process. The pressure-settlement curves were drew and the foundation bearing capacity under lateral fill height of 0 m, 4 m, 6 m, 8 m, 10 m, 12 m were measured. Test results showed that with the fill height increasing the bearing capacity increased significantly, it had been reached 815 kPa when the fill height was 10 m. But the growth was nonlinear, it first increased from 18.40% to 20.37% and then reduced to 8.59%. At last the bearing capacity reached 885 kPa while fill height exceeded 12 m. Meanwhile the errors between the calculated results and measured by model test were almost less than 10% so the algorithm was feasible. The conclusion is that the lateral fill is advantageous for improve the foundation bearing capacity and reduce project cost significantly when the settlement of the culverts foundation satisfied the design request, with the lateral fill increasing, the rate of the improvement first increases and then decreases, at last it tends to 885 KPa when fill height exceeded 12 m.

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