• Title/Summary/Keyword: Non-hydration

Search Result 136, Processing Time 0.021 seconds

Feasibility Study on the Use of CFBC Ash as Non-sintered Binder (순환유동층 보일러애시를 활용한 비소성 결합재로써의 활용 가능성 검토)

  • Kang, Yong Hak;Lim, Gwi Hwan;Kim, Sang Jun;Choi, Young Cheol
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.22 no.5
    • /
    • pp.119-126
    • /
    • 2018
  • Recently, the production of circulating fluidized bed combustion ash has been increased in thermal power plants. The addition of limestone for the desulfurizing effect of circulating fluidized bed boiler ash increases the content of CaO and $SO_3$ contained in ash, which is higher than the free fly ash in general fly ash. Unlike conventional fly ash, the circulating fluidized bed combustion ash has a high reactivity when it comes into contact with water due to its hydraulic properties and high free-CaO content. The aim of this study is to investigate the possibility of non-sintered binder by using self-cementing properties of circulating fluidized bed combustion ash. The mechanical and hydration characteristics were investigated according to the content of CFBC ash. In addition, the effects of gymsum type and content on the compressive strength and micro-structure of non-sintered binder pastes.

Reaction Properties of Non-Cement Mortar Using Ground Granulated Blast Furnace Slag (고로슬래그 미분말을 사용한 무시멘트 경화체의 반응 특성)

  • Park, Sun-Gyu;Kwon, Seung-Jun;Kim, Yun-Mi;Lee, Sang-Soo
    • The Journal of the Korea Contents Association
    • /
    • v.13 no.9
    • /
    • pp.392-399
    • /
    • 2013
  • The purpose of this study is to identify the manufacturing possibility of non-cement mortar using blast furnace slag and alkali accelerator. In this experimental study, the blast furnace slag which is the by-product of the steel industry substitute for cement, and the potassium hydroxide(KOH), calcium hydroxide ($Ca(OH)_2$) and sodium hydroxide(NaOH) as stimulus were added to each specimen. And the analysis on reaction property of non-cement mortar was conducted by measurement such as flexural and compressive strength, XRD, EDS and SEM. From the test results, it can be founded that $SiO_2$ and CaO included in the blast furnace slag are released and make the calcium silicate hydrate like the hydration reaction of the cement. Also, the continued study is need to reduce emission of $CO_2$ because of major content in filed of the building construction.

Quality Characteristics of Yukwa (Popped Rice Snack) made by Different Varieties of Rice (쌀 품종별 유과제조 특성)

  • Shin, Dong-Hwa;Kim, Myung-Kon;Chung, Tae-Kyu;Lee, Hyun-Yu
    • Korean Journal of Food Science and Technology
    • /
    • v.21 no.6
    • /
    • pp.820-825
    • /
    • 1989
  • Yukwa (one of most popular Korean traditional popped rice snacks) was made by four different varieties of rice, Shinsun (Japonica) and Hangang $(Japonica{\times}Indica)$ which are waxy rice and Dongjin (Japonica) and Samgang $(Japonica{\times}Indica)$ which are non waxy rice, for their quality by total expansion volume, hardness and brittleness. It was notified that hydration rate of waxy and non waxy rice for preparation of Yukwa were different by 30% and 42% in moisture content respectively soaked at $12^{\circ}C$ for 12 hours and the gelatinization temperature of their starch was $64.5-67.5^{\circ}C$ with no big difference by varieties. The quality of Yukwa was deeply related with amylose contents ranging from 18.5% of non waxy rice to 2-3% of waxy rice. Superior quality (p<0.05) was got from waxy rice. Lactic acid bacterial fermentation didn't improve the quality, and soybean and rice bran oil can be used for popping in even value.

  • PDF

Microstructure of Non-Sintered Inorganic Binder using Phosphogypsum and Waste Lime as Activator

  • Kim, Ji-Hoon;An, Yang-Jin;Mun, Kyung-Ju;Hyung, Won-Gil
    • Journal of the Korea Institute of Building Construction
    • /
    • v.18 no.3
    • /
    • pp.305-312
    • /
    • 2018
  • This study is about the development of a non-sintered binder (NSB) which does not require a sintering process by using the industrial by-products Phosphogypsum (PG), Waste Lime (WL) and Granulated Blast Furnace Slag (GBFS). In this report, through SEM analysis of the NSB paste hardening body, micropore analysis of paste using the mercury press-in method and microstructure observation were executed to consider the influence of the formation of the pore structure and the distribution of pore volume on strength, and the following conclusions were reached. 1) Pore structure of NSB paste of early age is influenced by hydrate generation amount by GBFS and activator. 2) Through observing the internal microstructure of NSB binder paste, it was found that the strength expression at early age due to hydration reaction was achieved with a large amount of ettringite serving as the frame with C-S-H gel generated at the same time. It was confirmed that C-S-H gel wrapped around ettringite, and as time passed, the amount generated continually increased, and C-S-H gel tightly filled the pores of hardened paste, forming a dense network-type web structure. 3) For NSB-type cement, the degree of formation of gel pores below $10{\mu}m$ had a greater influence on strength improvement than simple pore reduction by charging capillary pores, and the pore size that had the greatest effect on strength was micropores with diameter below $10{\mu}m$.

Characteristics of Opaque Endosperm Originated from a Rice Cultivar ′Pokhareli Mashino′ (벼품종 ″Pokhareli Mashino′에서 유래된 Opaque형질의 배유특성)

  • ;Mun-Hue Heu
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.34 no.2
    • /
    • pp.155-162
    • /
    • 1989
  • This experiment was conducted to investigate the endosperm characteristics of an opaque rice which was derived from an Indica cultivar Pokhareli Mashino. Grain apperance of opaque rice looked similar to the waxy grain, while the blue-color response to the iodine solution was similar to non-waxy endosperm. The shape of starch granules was alike each other, but their size were different each other with the smallest of the opaque rice. Their cristaline structure of starch granules were A type. The content of total protein and most of the amino-acids of opaque rice was about 1.5 times of other varieties. Alkali digestibility of the opaque rice was very low. Total water uptake and hydration rate of opaque rice was similar to non-waxy variety Tongil. Amylogram characteristics such as viscosity, setback and consistency of opaque rice revealed medium value between. waxy and non-waxy rice.

  • PDF

Clinical Efficacy of Combination Chemotherapy with Ifosfamide Cisplatin, and Etoposide(ICE) in Advanced Non-Small Cell Lung Cancer (진행성 비소세포 폐암 환자에서 Ifosfamide, Cisplatin Etoposide(ICE) 복합화학요법의 효과)

  • Lee, Gu;Kim, Byung Duk;Kang, Hee Jung;Lee, Sang Won;Oh, Hyun A;Bae, Sung Hwa;Lee, Jae Lyun;Lee, Kyung Hee;Hyun, Myung Soo;Shin, Kyeong Cheol;Jung, Jin Hong;Lee, Kwan Ho;Ryu, Hun Mo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.52 no.4
    • /
    • pp.309-316
    • /
    • 2002
  • Background: To evaluate the efficacy and toxicity of combination chemotherapy using ifosfamide, cisplatin, and etoposide in patients with advanced non-small cell lung cancer(NSCLC). Materials and methods: Thirty-three patients with inoperable NSCLC(stage IIIb+IV) who had measurable diseases, and had not been treated with chemotherapeutic drugs, were enrolled in this study(from March 1995 to December 1996). The patients received ifosfamide($1500mg/m^2/day$, a full drop with Mesna on days 1-5), Cisplatin ($80mg/m^2/day$ infusion with a hydration on day 2), and Etoposide ($100mg/m^2/day$ infusion for 2 hours on days 1-3). The treatment was repeated every 4 weeks. Results: Ten patients showed a partial responses (30.3%). The overall survival time of the responders was longer than that of the non-responders (median 55 vs 22 weeks, p=0.01). The toxicities of this treatment were tolerable. Grade 3 or 4 leukopenia was observed in 21%. There was 1 death related to febrile neutropenia. The non-hematologic toxicity was mild. The relative dose intensity given to the patients was 0.86 ifosfamide, 0.87 cisplatin, and 0.89 etoposide, showing an average dose intensity of 0.87. Conclusions: A combination regimen of ifosfamide, cisplatin, and etoposide is effective and tolerable for treating advanced non-small cell lung cancer.

A Study on Fluid Intake among Nursing Home Residents (시설노인의 수분섭취 실태분석 및 수분섭취 장애요인)

  • Oh, Hee-Young;Hur, Myung-Haeng;Kim, Jin-Sun
    • Journal of Korean Academy of Nursing
    • /
    • v.36 no.6
    • /
    • pp.959-967
    • /
    • 2006
  • Purpose: The purposes of this study were to examine the amount of daily fluid intake among nursing home residents and to explore the caregiver's perceived barriers to elderly's fluid intake. Method: Data was collected from 111 nursing home residents and 64 caregiver's in 4 nursing homes. A random, non-consecutive three days of 24 hour fluid intake was measured and recorded. The caregiver's perceived barriers to elderly's fluid intake was assessed using a structured questionnaire. Results: The average amount of daily fluid intake was 1,035(SD=359)ml with the range of 210m1 to 2,050ml. About 52% (n=58) of the subjects had a less than adequate fluid intake. The amount of daily fluid intake was significantly associated with age, mental status, physical functioning, and the number of oral medications ordered. The most frequently mentioned caregiver's perceived barrier was elderly's concern about incontinence with increased fluid intake. Conclusion: Inadequate fluid intake among nursing home residents is prevalent. To enhance adequate hydration of nursing home residents, an institution wide nursing intervention is necessary.

Effect of Morphology and Dispersibility of Silica Nanoparticles on the Mechanical Behaviour of Cement Mortar

  • Singh, Lok Pratap;Goel, Anjali;Bhattachharyya, Sriman Kumar;Ahalawat, Saurabh;Sharma, Usha;Mishra, Geetika
    • International Journal of Concrete Structures and Materials
    • /
    • v.9 no.2
    • /
    • pp.207-217
    • /
    • 2015
  • The influence of powdered and colloidal nano-silica (NS) on the mechanical properties of cement mortar has been investigated. Powdered-NS (~40 nm) was synthesized by employing the sol-gel method and compared with commercially available colloidal NS (~20 nm). SEM and XRD studies revealed that the powdered-NS is non-agglomerated and amorphous, while colloidal-NS is agglomerated in nature. Further, these nanoparticles were incorporated into cement mortar for evaluating compressive strength, gel/space ratio, portlandite quantification, C-S-H quantification and chloride diffusion. Approximately, 27 and 37 % enhancement in compressive strength was observed using colloidal and powdered-NS, respectively, whereas the same was up to 19 % only when silica fume was used. Gel/space ratio was also determined on the basis of degree of hydration of cement mortar and it increases linearly with the compressive strength. Furthermore, DTG results revealed that lime consumption capacity of powdered-NS is significantly higher than colloidal-NS, which results in the formation of additional calcium-silicate-hydrate (C-S-H). Chloride penetration studies revealed that the powdered-NS significantly reduces the ingress of chloride ion as the microstructure is considerably improved by incorporating into cement mortar.

Removal of Nitrate by Ferrous Cement Hydrates (2가철 시멘트 수화물에 의한 질산성 질소의 제거)

  • Kang, Wan-Hyup;Park, Tae-Sook;Park, Joo-Yang
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.19 no.1
    • /
    • pp.53-60
    • /
    • 2005
  • Ferrous cement hydrates made from hydrating Portland cement doped with Fe (II) were reported to reductively dechlorinate chlorinated organics and to reduce Cr (VI) to Cr (III). In this study, kinetics of nitrate removal by ferrous cement hydrates were investigated. Nitrate removal kinetics were characterized by experimental variables such as cement hydration, amount of cement addition, Fe (II) dose, pH, and byproducts. As a result, hydrated cement showed better performances than non-hydrated cement due to the formation of LDH (layered double hydroxide). Doping of Fe (II) into the cement was found to improve removal efficiency at high pHs by association with Fe (II) sorbed on cement hydrates as a reactive reductant. Reduction of nitrate produced ammonium as a major product, which accounted for 63.5% of the final products, and nitrite (0.15%) as a minor product. These results indicate that the developed media are effective as sorbent/reducing agents in the nitrate removal and the reaction mechanisms of nitrate removal are sorption and reduction.

Prediction of chloride ingress into saturated concrete on the basis of a multi-species model by numerical calculations

  • Nguyen, T.Q.;Baroghel-Bouny, V.;Dangla, P.
    • Computers and Concrete
    • /
    • v.3 no.6
    • /
    • pp.401-422
    • /
    • 2006
  • A multi-species model based on the Nernst-Planck equation has been developed by using a finite volume method. The model makes it possible to simulate transport due to an electrical field or by diffusion and to predict chloride penetration through water saturated concrete. The model is used in this paper to assess and analyse chloride diffusion coefficients and chloride binding isotherms. The experimental assessment of the effective chloride diffusion coefficient consists in measuring the chloride penetration depth by using a colorimetric method. The effective diffusion coefficient determined numerically allows to correctly reproduce the chloride penetration depth measured experimentally. Then, a new approach for the determination of chloride binding, based on non-steady state diffusion tests, is proposed. The binding isotherm is identified by a numerical inverse method from a single experimental total chloride concentration profile obtained at a given exposure time and from Freundlich's formula. In order to determine the initial pore solution composition (required as initial conditions for the model), the method of Taylor that describes the release of alkalis from cement and alkali sorption by the hydration products is used here. Finally, with these input data, prediction of total and water-soluble chloride concentration profiles has been performed. The method is validated by comparing the results of numerical simulations to experimental results obtained on various types of concretes and under different exposure conditions.