scholarly journals Solidification and Stabilization of Spent TBP/OK Organic Liquids in a Phosphate Acid-Based Geopolymer

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Teng Dong ◽  
Shuibo Xie ◽  
Jingsong Wang ◽  
Guodong Zhao ◽  
Qingchun Song
Keyword(s):  
Compressive Strength ◽  
Tributyl Phosphate ◽  
Setting Time ◽  
Tween 80 ◽  
Organic Liquids ◽  
Leaching Test ◽  
Freeze Thaw ◽  
Final Setting Time

A method for solidifying spent tributyl phosphate and kerosene (TBP/OK) organic liquids in a phosphate acid-based geopolymer (PAG) was investigated. The TBP/OK emulsion containing tween 80 (T80), TBP/OK organic liquids, and H3PO4 was prepared. The TBP/OK emulsion was mixed with metakaolin to obtain solidified TBP/OK forms (SPT). The compressive strength of the SPT was up to 59.19 MPa when the content of TBP/OK was 18%. The loss of compressive strength of SPT was less than 10% after immersion and less than 25% after freeze-thaw treatment. The final setting time was 40.0 h, and the shrinkage of SPT was nearly 3%. The leaching test indicated that the release of TBP/OK from hardened SPT was limited. Characterization of SPT suggested that solidification of TBP/OK using PAG occurred by physical encapsulation.

Behaviour of Calcium Alkali Orthophosphate Cements under Simulated Implantation Conditions

2008 ◽  
Vol 396-398 ◽  
pp. 213-216 ◽  
Author(s):  
Daniela Jörn ◽  
Renate Gildenhaar ◽  
Georg Berger ◽  
Michael Stiller ◽  
Christine Knabe
Keyword(s):  
Compressive Strength ◽  
Simulated Body Fluid ◽  
Clinical Application ◽  
Body Fluid ◽  
Setting Time ◽  
Great Decrease ◽  
Final Setting Time ◽  
Laboratory Conditions ◽  
Setting Times

The setting behaviour, the compressive strength and the porosity of four calcium alkali orthophosphate cements were examined under laboratory conditions (dry) and under conditions similar to those during clinical application (37°C, contact with body fluid). The results showed an increase of the setting times when specimens were covered with simulated body fluid. Especially, the final setting time (FHZ) was significantly higher for three of the four cements. Furthermore, when specimens were stored in SBF for 16h, an extensive decrease of the compressive strength was noted. The porosity was more than twice as high after 16h in SBF and this may be the cause for the great decrease of the compressive strength.

Preparation and Characterization of PMMA-Based Cements Containing Magnetic Nanoparticles for the Magnetic Hyperthermia

2013 ◽  
Vol 647 ◽  
pp. 155-159 ◽  
Author(s):  
Zheng Hai Tang ◽  
Xiao Wen Wang ◽  
Lin Pan ◽  
Yan Wen Hu ◽  
Yang Wu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Compressive Strength ◽  
Setting Time ◽  
Magnetic Hyperthermia ◽  
Control Material ◽  
Setting Reaction ◽  
Therapeutic Hyperthermia ◽  
Pmma Cement ◽  
Magnetic Fe3o4

Three types of polymethylmethacrylate(PMMA)-based cements containing magnetic (Fe3O4) particles were developed and their properties were evaluated. The commercial available PMMA cement (PMMAc) was used as a control material. The setting time of the cement extended while the compressive strength of the samples decreased with increasing Fe3O4 content. There was no obvious difference in peak temperature between the cements during the setting reaction. The cement with 10 wt% Fe3O4 in an alternating magnetic field (AMF) of 125 Gs and cement with 20 wt% Fe3O4 in an AMF of 100 Gs could generate enough heat for the therapeutic hyperthermia of bone metastasis.

scholarly journals A Feasibility Study on HPMC-Improved Sulphoaluminate Cement for 3D Printing

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2415 ◽  
Author(s):  
Zhu Ding ◽  
Xiaodong Wang ◽  
Jay Sanjayan ◽  
Patrick Zou ◽  
Zhi-Kun Ding
Keyword(s):  
Compressive Strength ◽  
3D Printing ◽  
Feasibility Study ◽  
Setting Time ◽  
Hydroxypropyl Methylcellulose ◽  
Hydration Heat ◽  
Heat Setting ◽  
Sulphoaluminate Cement ◽  
Final Setting Time ◽  
Experimental Parameters

A novel 3D printing material based on hydroxypropyl methylcellulose (HPMC)—improved sulphoaluminate cement (SAC) for rapid 3D construction printing application is reported. The hydration heat, setting time, fluidity of paste and mortar, shape retainability, and compressive strength of extruded SAC mortar were investigated. HPMC dosage, water-to-cement (W/C) ratio, and sand-to-cement (S/C) ratio were studied as the experimental parameters. Hydration heat results reveal HPMC could delay the hydration of SAC. The initial and final setting time measured using Vicat needle would be shortened in the case of W/C ratio of 0.3 and 0.35 with HPMC dosage from 0.5% to 1.5%, W/C ratio of 0.40 with HPMC dosage of 0.5%, 0.75%, and 1.5%, and W/C ratio of 0.45 with HPMC dosage of 0.45, or be extended in the case of W/C ratio of 0.4 with HPMC dosage of 1.0% and W/C ratio of 0.45 with HPMC dosage from 0.75% to 1.5%. Fluidity measurement shows HPMC significantly improves the shape retainability. Furthermore, the addition of HPMC remarkably increased the compressive strength of extruded mortar. The results showed that HPMC could be used to prepare 3D printing SAC having satisfactory shape retainability, setting time and compressive strength.

scholarly journals Comparison of Effects of Sodium Bicarbonate and Sodium Carbonate on the Hydration and Properties of Portland Cement Paste

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1033 ◽  
Author(s):  
Yuli Wang ◽  
Fengxia He ◽  
Junjie Wang ◽  
Qianku Hu
Keyword(s):  
Compressive Strength ◽  
Sodium Bicarbonate ◽  
Portland Cement ◽  
Cement Paste ◽  
Sodium Carbonate ◽  
Ordinary Portland Cement ◽  
Setting Time ◽  
Sprayed Concrete ◽  
Final Setting Time ◽  
Portland Cement Paste

Carbonates and bicarbonates are two groups of accelerators which can be used in sprayed concrete. In this study, the effects of the two accelerators sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) (0%, 1%, 2%, 3%, and 4% by weight of ordinary Portland cement OPC) on the properties of OPC paste were compared. The results show that both of them could accelerate the initial and final setting time of OPC paste, but the effect of the two accelerators on the compressive strength were different. After 1 day, sodium bicarbonate at 3% had the highest strength while sodium carbonate at 1% had the highest strength. After 7 days, both of the two accelerators at 1% had the highest compressive strength. After 28 days, the compressive strength decreased with the increase of the two. The improved strength at 1 and 7 days was caused by the accelerated formation of ettringite and the formation of CaCO3 through the reactions between the two with portlandite. The decrease of strength was caused by the Na+ could reduce the adhesion between C-S-H gel by replacing the Ca2+. NaHCO3 was found be a better accelerator than Na2CO3.

Preparation and Characterization of Silk Fibroin/Calcium Phosphate Composite

2011 ◽  
Vol 332-334 ◽  
pp. 1655-1658
Author(s):  
Biao Wang ◽  
Rui Juan Xie ◽  
Yang Yang Huang
Keyword(s):  
Compressive Strength ◽  
Calcium Phosphate ◽  
Silk Fibroin ◽  
Solid Phase ◽  
Setting Time ◽  
Testing Machine ◽  
X Ray Diffraction ◽  
Acicular Crystal ◽  
Setting Times

In this paper, calcium phosphate cement (CPC) was prepared with tetracalcium phosphate (TTCP)/dicalcium phosphate anhydrous (DCPA) system as solid phase and phosphate buffered solution (PBS) as liquid phase, then silk fibroin (SF) was added into CPC to form silk fibroin/calcium phosphate composite. To study the effect of SF on the properties of composite, different mass fraction of SF was added into the composite. The surface morphology was observed by Scanning Electron Microscope. The setting time was investigated by ISO Cement Standard Consistency Instrument. The structure of the composite was studied by X-ray diffraction and infrared spectroscopy. Mechanical properties of samples were tested by Instron Universal Testing Machine. The results showed that the particles of SF could be seen obviously in the surface of all composite, and acicular crystal of hydroxyapatite (HA) was formed in the hardening body of both the composite and the pure CPC. The acicular crystal of HA derived from composite with SF appeared to be thinner. The setting times of the composites were all between 9 to 15min. Compared to pure CPC, the compressive strength and work-of-compressive of composites were all improved. The compressive strength of the composite with 1% SF increased obviously.

Preparation and Characterization of Polycarboxylate Superplasticizer Synthesized at Non-Aqueous Condition

2013 ◽  
Vol 357-360 ◽  
pp. 1358-1361
Author(s):  
Xiao Liu ◽  
Zi Ming Wang ◽  
Xu Liang ◽  
Jie Zhu ◽  
Yang Zhang
Keyword(s):  
Fourier Transform ◽  
Polyethylene Glycol ◽  
Setting Time ◽  
Aqueous System ◽  
Hydration Heat ◽  
Time Interval ◽  
Final Setting Time ◽  
Polycarboxylate Superplasticizer ◽  
Convenient Preparation

Polycarboxylate superplasticizer (PCE) was synthesized in non-aqueous system to achieve the rapid transportation and convenient preparation. The results showed that, PCE using isopentenyl polyethylene glycol (TPEG) or isobutenyl polyethylene glycol (IPEG) as macromonomer exhibited excellent paste fluidities and retaining properties at 80°C and 75°C, respectively. Fourier Transform infrared spectroscopy (FTIR) measurement confirmed the polymerization between monomers. The synthesized PCE as solid state was dissolved into water to prepare the PCE solution, and its cement application performances were studied systematically. The results showed that PCEs with good paste fluidity retentions exhibited the longest final setting time and the shortest setting time interval. The hydration heat results showed that PCEs with good fluidity properties can significantly delay the hydration process and lower the hydration heat.

scholarly journals Physicochemical Properties and Dentin Bond Strength of a Tricalcium Silicate-Based Retrograde Material

2017 ◽  
Vol 28 (1) ◽  
pp. 51-56 ◽  
Author(s):  
Camila de Paula Telles Pires Lucas ◽  
Raqueli Viapiana ◽  
Roberta Bosso-Martelo ◽  
Juliane Maria Guerreiro-Tanomaru ◽  
Josette Camilleri ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Bond Strength ◽  
Physicochemical Properties ◽  
Setting Time ◽  
Tricalcium Silicate ◽  
Final Setting Time ◽  
Root Canal Dentin ◽  
Post Hoc ◽  
Push Out

Abstract The aim of this study was to evaluate the physicochemical properties and the apical dentin bond strength of the tricalcium silicate-based Biodentine in comparison to white MTA and zinc oxide eugenol-based cement (ZOE). Setting time and radiopacity were evaluated according to ISO 6876:2012 specification. Final setting time, compressive strength and pH were also assessed. Material’s bond strength to the apical root canal dentin was measured by the push-out assay. Data were analyzed by ANOVA and Tukey-Krammer post-hoc test. Biodentine presented the shortest initial (16.2±1.48 min) and final setting time (35.4±5.55 min). Radiopacity of Biodentine (2.79±0.27 mmAl) does not agree with ISO 6876:2012 specifications. On the other hand, Biodentine showed higher compressive strength after 21 days (37.22±5.27 MPa) and higher dentin bond strength (11.2±2.16 MPa) in comparison to white MTA (27.68±3.56 MPa for compressive strength and 2.98±0.64 MPa for bond strength) (p<0.05). Both MTA and Biodentine produced an alkaline environment (approximately pH 10) (p>0.05) compared to ZOE (pH 7). It may be concluded that Biodentine exhibited faster setting, higher long-term compressive strength and bond strength to the apical dentin than MTA and ZOE.

scholarly journals Compressive Strength and Setting Time of MTA and Portland Cement Associated with Different Radiopacifying Agents

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Mario Tanomaru-Filho ◽  
Vanessa Morales ◽  
Guilherme F. da Silva ◽  
Roberta Bosso ◽  
José M. S. N. Reis ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Zirconium Oxide ◽  
Setting Time ◽  
Strontium Carbonate ◽  
Strength Test ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Compressive Strength Test ◽  
Initial Setting

Objective. The aim of this study was to evaluate the compressive strength and setting time of MTA and Portland cement (PC) associated with bismuth oxide (BO), zirconium oxide (ZO), calcium tungstate (CT), and strontium carbonate (SC). Methods. For the compressive strength test, specimens were evaluated in an EMIC DL 2000 apparatus at 0.5 mm/min speed. For evaluation of setting time, each material was analyzed using Gilmore-type needles. The statistical analysis was performed with ANOVA and the Tukey tests, at 5% significance. Results. After 24 hours, the highest values were found for PC and PC + ZO. At 21 days, PC + BO showed the lowest compressive strength among all the groups. The initial setting time was greater for PC. The final setting time was greater for PC and PC + CT, and MTA had the lowest among the evaluated materials (P<0.05). Conclusion. The results showed that all radiopacifying agents tested may potentially be used in association with PC to replace BO.

Early Strength Agent on the Properties of Reinforcement Materials Research

2013 ◽  
Vol 477-478 ◽  
pp. 936-940
Author(s):  
Chang Zheng Sun ◽  
Xiao Ping Zhang ◽  
Hai Nan Zhao ◽  
Qiang Gao
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Sodium Nitrite ◽  
Setting Time ◽  
Initial Flow ◽  
Final Setting Time ◽  
Reinforcement Material ◽  
Materials Research ◽  
Early Strength ◽  
Nitrite Content

In the trial, the author explores sodium nitrite, triethanolamine and sodium on fluidity initial and final setting time, flexural strength and compressive strength and other properties, of early strength reinforcement material. The results showed that, when sodium nitrite content is 0.2%, triethanolamine content is 0.05%, the dosage of sodium sulfate is 0.8%, final setting time for 58min, the initial flow greater than 320[mm], 30min flow greater than 280[mm], 2h compressive strength of 30[MPa], 1d bending greater than 10[MPa], 28d compressive strength greater than 90[MPa], on the early strength reinforcement, meet construction requirements.

Research on the Compound early Strength Agent to the Performance of Super High early Strength Grouting Material

2013 ◽  
Vol 477-478 ◽  
pp. 996-1001 ◽  
Author(s):  
Xiao Ping Zhang ◽  
Chang Zheng Sun ◽  
Tong Feng Zhao
Keyword(s):  
Compressive Strength ◽  
Sodium Sulfate ◽  
Setting Time ◽  
Cementitious Material ◽  
Final Setting Time ◽  
Grouting Material ◽  
Reinforcement Material ◽  
Reasonable Proportion ◽  
Strength Material ◽  
Early Strength

The effect of sodium sulfate, triethanolamine and early strength agent A on the early strength reinforcement material final setting time, flexural strength and compressive strength and structure were investigated. The results show that the composite of sodium sulfate, triethanolamine and early strength agent according to a reasonable proportion, the dosage of 0.35% -0.40% (in cementitious material quality), the final setting time of early strength material for 50 to 60 min, Initial fluidity over 320mm, 0.5h flow degree greater than 280mm, 1d bending greater than 12MPa and 28d compressive strength greater than 80MPa, meet the requirements.

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