Hydrothermal Synthesis of Xonotlite Fibers and Investigation on their Thermal Property

2010 ◽  
Vol 105-106 ◽  
pp. 841-843 ◽  
Author(s):  
Fei Liu ◽  
Ling Ke Zeng ◽  
Jian Xin Cao ◽  
Bo Zhu ◽  
An Yuan

A hydrothermal route for preparing large size xonotlite fibers without special instruments and synthesis conditions was development. Effect of pH values in system on the crystal phase and morphology of synthesized xonotlite fibers was studied by using XRD and SEM. The results indicated that the different pH systems have little effect on the crystallinity of synthesized xonotlite, but have great impact on the morphology of xonotlite fibers. The higher pH value is, the lager scale xonotlite fibers appear when the pH values are among 12.0, 12.5, 13.0 and 13.5. The formation of xonotlite fibers was promoted and xonotlite fibers with 10-30 μm in length and 100-200 nm in diameter were prepared at 220 °C for 15 h in the system of pH 13.5. The evaluation of thermal property revealed that synthesized fibers were excellent in thermal stability at high temperature, and could be potential candidate as reinforcement reagents in composite areas.

2010 ◽  
Vol 434-435 ◽  
pp. 787-789
Author(s):  
Fei Liu ◽  
Ling Ke Zeng ◽  
Jian Xin Cao ◽  
Qian Lin ◽  
Jing Li

Carbide slag was used as raw materials for the first time to prepare xonontlite whiskers via a hydrothermal route without special instruments and synthesis conditions. And the effect of pH value of emulsion of carbide slag and hydrothermal conditions on removal rate of impurities, morphology and crystallinity of synthesized xonotlite whiskers were explored using ICP, SEM and XRD techniques. The results indicated that the carbide slag after purification could be used to prepare xonotlite whiskers, and different pH values of emulsion of carbide slag had great impact on the removal rate of impurities and morphology of xonotlite whiskers. Xonotlite whiskers with 20-40 μm in length and 100-500 nm in diameter were hydrothermally synthesized at 230 °C for 15 h with using silicic acid as kiesel material.


2016 ◽  
Vol 847 ◽  
pp. 479-484 ◽  
Author(s):  
Ya Lu ◽  
Ming Li ◽  
Zi Han Guo ◽  
Xiao Yang Guo

In view of the common polymer retarder of AMPS has poor sedimentation stability for slurry in high temperature, and thickening curve for unusual problems, a new terpolymers retarder PSIH which can solve the problem for the large temperature difference was synthesized by free radical aqueous solution copolymerization using styrene sulfonate (SSS), Itaconic acid (IA) and unsaturated hydroxyl ester monomers X . The structure and thermal stability of the copolymer was characterized with gel permeation chromatography (GPC), infrared spectroscopy (IR), and thermal gravimetric analysis (TG). The application performance of the retarder was assessed. The results demonstrated as follows. 1) The preferred synthesis conditions of the retarder is: the mass ratio of SSS/IA/X=9: 3: 1, temperature=60°C, initiator concentration =2%, the reaction time=5h, pH value was controlled in the neutral bias acidity. 2) Synthetic copolymer is the target product with appropriate molecular weight and has good thermal stability with thermal decomposition temperature of the main chain up to 375°C. 3) Compared with ordinary retarder the PSIH has merits as follows: excellent thermal resistant ability and sedimentation stability in high temperature; the rapid development of compressive strength in low temperature, and a big temperature span (30 °C~150 °C). The thickening time of the slurry with 1.0% PSIH is 245 min at 150°C; the compressive strength of cement with the same dosage can get up to 4.7MPa at 30 °C. In short, PSIH has excellent ability to cope with large temperature difference, providing a strong technical support for complex deep well cementing.


2015 ◽  
Vol 8 (1) ◽  
pp. 58-63
Author(s):  
Wang Chunsheng ◽  
Sun Yingfan ◽  
He Chenglin ◽  
Zhang Haipeng ◽  
Du Qiuying

Under the constraints of high temperature and heterogeneity, the common profile control agent can not effectively plug the steam channeling. To address this issue, it is necessary to develop the high temperature resistance steam channeling plugging agent to improve the steam suction profile in the heavy oil reservoir. This paper used Simple Variable Method to optimize the content of the components of the high temperature resistant plugging agent. Static performances evaluation aims to study the influence rules of the formation condition (temperature, salinity and pH value). Dynamic evaluation is used to study its performance (plugging ratio, residual resistance factor, scouring resistance and thermal stability) in the sand-filled pipe to testify its applicability. The ratio of the component and the injection sequence are shown as follows: 0.03% coagulant +2.2% cross-linking agent I + 1.2% cross-linking II + 6% high efficient main agent. The evaluation experiment results show that the gel can resist at least 280ºC, the plugging ratio is above 93.1%. The plugging ratio only have a 8.43% reduction after scoured by 15 PV steam (280ºC). After a 10-day thermal stability experiment (280 ºC), the plugging ratio is still above 80%. The result indicated that the plugging agent is suitable for the improvement of steam suction profile. The suggested way of injection is also provided.


2011 ◽  
Vol 382 ◽  
pp. 384-387 ◽  
Author(s):  
Fei Liu ◽  
Xiao Dan Wang ◽  
Jian Xin Cao

The different pH values in CaO-SiO2-H2O systems were taken into account to prepare xonotlite whiskers without any surfactant, special instruments and synthesis conditions. Effect of pH values in system on the crystallinity and morphology of synthesized xonotlite whiskers was studied by using XRD and SEM techniques. The results indicated that the different pH values in system had little effect on the crystallinity of synthesized xonotlite, but posed significant impact on the morphology of xonotlite whiskers. The higher pH value is, the lager scale xonotlite whiskers appear. Little whiskers were synthesized in the system of pH 11.5, but in the system of pH 13.0, the formation of xonotlite whiskers was promoted and xonotlite whiskers with 20-40 μm in length and 400 nm in diameter were prepared at 225 °C for 15 h.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1247
Author(s):  
Fatih Oz ◽  
Emel Oz ◽  
Eyad Aoudeh ◽  
A. M. Abd El-Aty ◽  
Maomao Zeng ◽  
...  

Herein, the presence of heterocyclic aromatic amines (HAAs) in 24 different commercial ultra-high temperature processed (UHT) milk types was investigated. The dry matter and pH values of the samples were also determined. The milk types showed significant differences (p < 0.01) regarding the dry matter, pH values, and individual HAAs and total HAAs. The milk sample dry matter and pH values were in the range of 8.56–13.92% and 6.66–6.91, respectively. The growing up milk samples had the highest dry matter and pH values. While no significant correlation between the total HAAs and dry matter was found, a negative correlation (p < 0.01) between the total HAAs and pH value was determined. Among the tested HAAs, five compounds, (IQx (up to 0.06 ng), IQ (up to 0.10 ng), MeIQx (up to 0.55 ng), MeIQ (up to 1.97 ng), and PhIP (up to 0.39 ng)) were quantified in the samples. The average total HAAs of the samples ranged from 0.13 to 0.67 ng; however, one milk sample (200 mL) contained between 10.10 and 53.35 ng total HAAs. Therefore, it was shown that protein fortification and lactose hydrolysis substantially increased the formation of HAAs in UHT milk.


Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization


Alloy Digest ◽  
2017 ◽  
Vol 66 (12) ◽  

Abstract Nippon Sumitomo Super625 is a nickel alloy with an optimization of compositional elements for thermal stability and hot workability. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming. Filing Code: Ni-740. Producer or source: Sumitomo Metal USA Corporation.


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