• Advances in concrete construction
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• v.9 no.1
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• pp.33-41
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• 2020

In this study, polyethylene glycol (PEG) and polyacrylamide (PAM) have been used as self-curing agents to produce self-curing concrete (SC). Compressive strength, ultrasonic pulse velocity (UPV), bulk electrical resistivity, chloride ion penetrability, water permeability, and main microstructural characteristics were examined under different curing regimes, and compared to those of the control concrete mixture with no self-curing agents. One batch of a control mixture and one batch of a SC mixture were air-cured in the lab to act as non-water-cured samples. The water curing regimes for the control mixture included continuous water curing for 3, 7, and 28 days and periodical moist curing using wetted burlap for 3 and 7 days. Curing regimes for the SC mixtures included 3 days of water curing and periodical moist curing for 3 and 7 days. SC mixtures showed better microstructure development and durability performance than those of the air-cured control mixture. A short water curing period of 3 days significantly improved the performance of the SC mixtures similar to that of the control mixture that was water cured for 28 days. SC concrete represents a step towards sustainable construction due to its lower water demand needed for curing and hence can preserve the limited water resources in many parts of the world.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.465-470
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• 2015

The curing of epoxy asphalt mixture depends on the chemical reaction of epoxy resin and the curing agent. The curing level of epoxy asphalt mixture needs to be predicted in order to decide traffic opening time and to establish further construction plans. In this study, chemical analysis of the prediction model was executed to expand the applicability of the previous prediction model. Consequently, the curing level prediction model of epoxy asphalt concrete mixture was proposed using the concentration ratio and the acid value ratio. According to the results of outdoor curing experiments, the final prediction model showed that the correlation coefficient is greater than 0.971. Precise prediction results of different composition epoxy asphalt were obtained by reflecting the chemical composition ratios in the curing level prediction model.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.217-230
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• 1994

The purpose of this study was to assess the 24-hour shear bond strength of amalgam to glass ionomer cement, using five different intermediaries. The intermediaries used in this study were Scotchbond 2 (light curing dentin adhesive), Panavia (resin cement), liquid' of glass ionomer cement (chemical curing & light curing), and uncured mixture of light curing glass ionomer cement. This study was operated with 48 specimens devided into 6 groups. The experimental groups are as follows: Group 1 : Bonded Amalgam to chemical curing glass ionomer cement with liquid of chemical curing glass ionomer. Group 2 : Bonded Amalgam to light curing glass ionomer cement with liquid of chemical curing glass ionomer. Group 3: Bonded Amalgam to light curing glass ionomer cement with resin cement. Group 4: Bonded Amalgam to light curing glass ionomer cement with light curing dentin adhesive. Group 5: Bonded Amdlgam to light curing glass ionomer cement with liquid of light curing glass ionomer. Group 6: Bonded Amalgam to light curing glass ionomer cement with uncured mixture of light curing glass ionomer cement. 30 minutes after amalgam condensation, all specimens were stored for 24 hours in water at $37^{\circ}C$ and tested with Instron (1122). The following results obtained: 1. The shear bond strength of group 6 was higher than those of the other groups (46.7 kgf/$cm^2$, p<0.05). 2. The shear bond strength of resin cement intermediary group was lower than that of the group using uncured mixture of light curing glass ionomer cement. 3. The results of group 1 and group 2 were different, even though the inter-me diaries used were same. 4. Intermediary of Group 5 did not show complete set in Scanning Electromicroscopic examination. 5. Light-curing dentin adhesive did not show any bonding ability to amalgam.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.489-494
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• 2010

A geo-composite soil (GCS) is a stabilized mixture of bottom ash, cement and dredged soil. Various samples with different mass ratios of mixtures were tested under curing time of 7 and 28 days to investigate physical properties and compressive strength. This paper focused on the effect of bottom ash on the strength characteristics of Busan marine dredged soil. Cement has been added as an additive constituent to enhance self-hardening of the blended mixture. The unconfined compressive strength of GCS increases with an increase in curing time due to pozzolanic reaction of the bottom ash. The strength after 28 days of curing is found to be approximately 1.3 to 2.0 times the strength after 7 days of curing, regardless of mixture conditions. The secant modulus of GCS is in the range of 55 to 134 times the unconfined compressive strength. The correlation of unconfined compressive strength with bottom ash content and initial void ratio are suggested.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.1
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• pp.33-41
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• 2000

Fiber reinforced metal laminates(FRMLs) were new type of hybrid materials. FRMLs consist of high strength metals(Al 5052-H34) and laminated fiber with structural adhesive bond. The effect of resin mixture ratios on the fatigue crack propagation behavior and mechanical properties of aramid fiber reinforced aluminum composites was investigated. The epoxy, diglycidylether of bisphenol A(DGEBA), was cured with methylene dianiline(MDA) with or without an accelerator(K-54). Eight kinds of resin mixture ratio were used for the experiment ; five kinds of FRMLs(1)(mixture of epoxy and curing agent) and three kinds of FRMLs(2)mixture of epoxy, curing agent and accelerator). The characteristic of fatigue crack propagation behavior and mechanical properties FRMLs(2) shows more effecting than that of FRMLs(1).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.1
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• pp.59-64
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• 2004

We have fabricated the polymer dispersed liquid crystal (PDLC) cell where a control of phase separation is very important. The factors to influence the phase separation are mixing ratio of LC and polymer, curing temperature and UV intensity. In this paper, we inspected the change of a phase separation as a function of curing temperature for the mixture of E7 and. NOA65 with different ratios. When the LC concentration is less than polymer such as LC:NOA65 = 40:60wt％, the PDLC cell is influenced strongly by the curing temperature. However, when the LC concentration is much less than polymer such as LC:NOA65 = 80:20wt％, it is influenced slightly by the curing temperature. The reason is because the mixture shows upper critical solution temperature behavior and therefore it is important to know the behavior of phase separation as a function of curing temperature of the mixture.

• Korean Journal of Poultry Science
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• v.45 no.1
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• pp.29-39
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• 2018

The goal of the present work was to determine the optimal addition amounts of liquid smoke and curing mixture to develop Chuncheon Dakgalbi with improved preference and shelf-life. In the first experiment, Chuncheon Dakgalbi was prepared with different amounts of liquid smoke. In the second experiment Chuncheon Dakgalbi was prepared with various amounts of curing mixture and 0.1% (w/w) liquid smoke. Different amounts of liquid smoke resulted in different aroma patterns, which were observed using an electronic nose, and Dakgalbi with 0.1% (w/w) liquid smoke had the highest score in overall acceptability. The addition of liquid smoke and curing mixture inhibited the growth of bacteria, slowed down the decline in pH, and delayed increased in volatile basic nitrogen contents and lipid oxidation. However, no clear effects were observed on instrumental color. From a consumer preference test, the highest preference score was achieved by added 0.2% (w/w) curing mixture. Liquid smoke and curing mixture extended shelf-life and improved preference of Chuncheon Dakgalbi. Considering the physicochemical, microbiological and consumer preference, it was recommended to add 0.1% (w/w) liquid smoke and 0.2% (w/w) curing mixture to Chuncheon Dakgalbi to enhance shelf-life and preference.

• Elastomers and Composites
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• v.19 no.3
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• pp.163-177
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• 1984

The effect of curing temperature increase and sulfur amount added were studied with natural and synthetic rubbers. Also, the effects of TMTD, MBTS and mixture of zinc soaps of high molecular fatty acids added to natural rubber were investigated respectively. The experimental results showed that, in the case of the conventional curing ($145^{\circ}C$), natural rubber, compared with synthetic rubber, gave higher values in elongation, tensile strength, cure rate, and lower values in modulus change. But, at high temperature curing ($180^{\circ}C$), natural rubber showed faster reversion rate, and higher heat build-up compared to synthetic rubber, than in the conventional curing. Also, natural rubber produced at high temperature showed severe degradation in hardness and tensile strength before heat-aging as well as in hardness, modulus and tensile strength after heat-aging. Improved reversion effect was obtained with natural rubber either by blending mixture of zinc soaps of high molecular acids or by applying semi-efficient vulcanization system.

• Current Research on Agriculture and Life Sciences
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• v.18
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• pp.61-69
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• 2000

This study was conducted to investigate most effective the optimum lime content for lime-clay modification. To achieve the aim, characteristics of compaction and compressive strength were tested by adding of 0, 5, 10, 15 and 20% lime (Hydrated lime) of dry weight of the clay. Distilled water was added 10, 15, 20 and 25% of dry weight of lime-clay mixture. In this test, the compressive strength of the specimens was measured according to the following curing period : 7, 21, 28, 35 and 49 days. The results are as follows. (1) As lime additive increased, the optimum moisture content of lime-clay mixture was increased and the maximum dry density was decreased. (2) The soil mixture of 20% of the moisture content and 10% of lime additive was shown the maximum compressive strength. (3) As curing period longer, the compressive strength was increased but after 21 curing days, the increasing rate of compressive strength was low as compared with earlier its value. (4) In the range of 20% of the moisture content, compressive strength of mixture of 10% lime additive increased twice compared with that of mixture of 0% lime additive. (5) All of the lime-clay are possible to use for an sub-base material and 20% of moisture content of lime-clay mixture is possible to use for a base material.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.4
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• pp.2761-2769
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• 1972

The following results were obtained by the compression test of 3, 7, 14 and 28 days cured lime soil mixtures. The soil used in this test was clayey soil(sand : 20% silt : 45%, clay : 35%) and the rates of hydrated lime mixture for the dry weight of soil were 4, 8, 12, 19 and 20 percents. 1. The optimum moisture content increases and the maximum dry density decreases with the increase of the lime content. 2. The compacted moisture for the maximum strength in lime soil mixture increases with the increase of the lime content and the increase of curing periods. 3. The compressive strength increase of curing periods and its increasing ratio is largest at the 8 percent lime content. 4. The line content for the maximum strength decreases with increase of curing period and the largest strength shows at the 8 percent lime content when the curing period is over two weeks. 5. It seems to depend on the temperature effect that the compressive strength of lime soil mixtures cured in soil shows the lowest value. Accordingly, the effect of curing moisture does not influence to the strength of lime soil mixtures as much as the variation of curing temperature.