In this study, the hydrogen sulfide removal performance of materials that can be used instead of NaOH was evaluated to reduce the amount of NaOH, a harmful substance used in chemical cleaning methods. Three alternative chemical agents were evaluated: commercially available chemical-based CB, enzyme-based EB, and natural substance-based NB. The hydrogen sulfide removal performance evaluation consisted of three lab tests: the EL608 method, a method using a bag, a method using a sensor and a chamber, and a field test conducted on a scrubber in operation in the actual field. As a result of evaluation by the EL608 Method, CB was 92.3% (±2.9%), EB 60.5% (±5.8%), and NB 88.3% (±3.6%), similar or somewhat similar to NaOH (5%) 99.8% (0.1%). In the evaluation of the hydrogen sulfide removal performance using Bag, the Michaelis-Menten coefficient was CB 4.30 and EB 5.30, lower than NaOH 6.60, and the affinity for hydrogen sulfide was evaluated to be stronger. Even in the method using the sensor and chamber, CB and EB showed similar hydrogen sulfide removal performance of NaOH, but NB showed low treatment performance. In the evaluation using the scrubber in the actual field, the treatment efficiency of CB and EB was higher than that of NaOH under all hydrogen sulfide inlet concentration conditions. If microorganisms grow on the packing material filled inside the scrubber, treatment efficiency may decrease. In order to prevent this phenomenon, the microbial growth inhibitory function of alternative materials was evaluated, and CB, EB, and NB were all superior to NaOH. As a result of this study, it was shown that CB and EB can replace NaOH because they have excellent performance in removing hydrogen sulfide and inhibiting microbial growth.
This study examined the factors influencing the purchase intention of meat substitutes. A survey was conducted on 589 consumers in Korea (297 people) and China (292 people). The perception of meat substitute foods was lower in Korean consumers than in Chinese consumers, but there was no significant difference. The purchase intention of meat substitute foods was lower in Korean consumers than in Chinese consumers (p<0.01). Korean consumers’ perception of meat substitute foods was higher in males than in females (p<0.01). The purchase intention of meat substitute foods also showed the same trend (p<0.001). Chinese consumers’ perception of meat substitute foods was higher in males than in females. The overall purchase intention of meat substitute foods was significantly higher in males than in females (p<0.05). The perception of meat substitute foods by Korean consumers’ was higher in their 40s and 50s than in their 20s and 30s. The purchase intention of meat substitute foods was also high in their 40s and 50s (p<0.01). On the other hand, the perception of meat substitute foods by Chinese consumers’ was higher in their 20s and 30s than in their 40s and 50s (p<0.01). The purchase intention of meat substitute foods also showed the same trend (p<0.01). Korean consumers’ perception of meat substitute foods had a significant positive effect on the purchase intention of meat substitutes (p<0.001). Chinese consumers’ perception of meat substitute foods also had a significant positive effect on the purchase intention of meat substitute foods (p<0.001). Overall, food technology neophobia has a significant negative effect on the purchase intention of meat substitutes (p<0.05).
This research extends the seminal work on the role of haptic (touch) information for consumers’ purchase decisions in both online and store shopping settings. Especially, this research focuses on which information consumers rely on as substitutes for haptic information when they cannot touch products at online shopping. A conceptual model is developed to investigate and compare the relative importance of touch, brand, virtual word-of-mouth, and product design. The proposed model is tested with the data collected from 380 consumers in an Asian country (Japan). The empirical results on two product categories (leather bags and smart phone cases) suggest that 1) consumers rely on other information than touch for online shopping, 2) the priority of substitute information differs depending on product categories, and 3) the priority also changes between online and store shopping for the same product category.
In this study, we investigated primary biocompatibility and osteogenic gene expression of porous granular BCP bone substitutes with or without strontium (Sr) doping. In vitro biocompatibility was investigated on fibroblasts like L929 cells and osteoblasts like MG-63 cells using a cell viability assay (MTT) and one cell morphological observation by SEM, respectively. MTT results showed a cell viability percent of L929 fibroblasts, which was higher in Sr-BCP granules (98-101%) than in the non-doped granules (92-96%, p< 0.05). Osteoblasts like MG-63 cells were also found to proliferate better on Sr-doped BCP granules (01-111%) than on the non-doped ones (92-99%, p< 0.05) using an MTT assay. As compared with pure BCP granules, SEM images of MG-63 cells grown on sample surfaces confirmed that cellular spreading, adhesion and proliferation were facilitated by Sr doping on BCP. Active filopodial growth of MG-63 cells was also observed on Sr-doped BCP granules. The cells on Sr-doped BCP granules were well attached and spread out. Gene expression of osteonectin, osteopontin and osteoprotegrin were also evaluated using reverse transcriptase polymerase chain reaction (RT-PCR), which showed that the mRNA phenotypes of these genes were well maintained and expressed in Sr-doped BCP granules. These results suggest that Sr doping in a porous BCP granule can potentially enhance the biocompatibility and bone ingrowth capability of BCP biomaterials.
It is necessary to improve the esthetic and function in the patient with oral and maxillofacial bone defects. Synthetic bone substitute materials and anorganic bovine bone mineral(ABBM) have been used for clinical restoration. The purpose of this study was to observe the biocompatibility and bone formation of synthetic hydroxyapatite(SHA) and ABBM in hole of rabbit's tibia. After specimens with SHA and ABBM at 8 weeks were fixed in 10% neutral formalin solution, dehydrated, and embedded with spurr low viscosity, they were cut by 500um with slow diamond wheel saw and grinded up to 200um in thickness. These specimens were coated with carbon and examined with r efraction microscope for bone density. Refraction microscopic features of 8 weeks in synthetic HA showed network-like new bone forming trabecular pattern attached to resorbed HA. Less well calcified trabecular bone surrounding conglomerated HAs showed irregular arrangement of numerous osteocytes. There was not completely filled in defected area by new bone trabecular. New trabecular bone formation by ABBM was more prominent and completely compacted in defect hole at 8 weeks. It suggested that although bone formation activity of AMMB might be superior to that on synthetic HA, both group would be the good biocompatibility in this experiment.
Twenty three samples of man-made mineral fibers (MMMF) were collected and analyzed for their mineral contents using a transmission electron microscope equipped with energy dispersive X-ray analyzer (TEM-EDX). Five glass fibers showed a straight fiber type without branches with average diameter ranged from 2.6㎛ to 5.6㎛ and average length 12.2∼29.6㎛. The major atomic compositions of the glass fibers were Na, Mg, Si, Ca, and Fe with a little variance among them and contained trace amounts of Al and Si. Eleven rock wool fibers also showed a straight fiber type without branches. The rock wool fibers used in 3 insulation panel and 1 insulation tube had average diameter 13.6∼26.4㎛ and average length 13.6∼26.4㎛. The major atomic compositions of the rock wool fibers were Na, Mg, Al, Si, S, Ca, Fe, and Cu with a little variance among them. Two of rock wool sealant fibers and one of coating material fibers had average 0.8∼ 2.2㎛ diameter and 9.9∼16.2㎛ average length. The major atomic compositions of the fibers were Mg, Al, Si, Ca, and Fe with a little variance among them and contained trace amount of S. The fibers in the rock wool coating materials contaminated partially with another type of fibers. Four of rock wool ceiling board showed 0.9∼2.04㎛ average diameter and 4.3∼15.2㎛ average length. The major atomic compositions of the fibers were Mg, Al, Si, S, Ca, and Fe with a little variance among them and contained trace amounts of Na, K, and Ti. Three of long glass fibers showed a mass appearance with finely splitted fibers, and the major atomic compositions of the fibers were Na, Mg, Al, Si, S, Ca, and Fe with no variance among them. One type of ceramic fiber showed 2.9±1.59㎛ average diameter and 20.3±9.38㎛ average length. The major compositions of the fibers were Al, Si, and S. A gypsum board and a perlite and a calcium silicate insulation material all showed aspect ratio less than 3:1, indicating non-fibrous materials. The major compositions of the gypsum board particles were Al, Si, S, K, Ca, and Fe, The perlite particles were consisted of Na, Al, Si, S, K, Ca, and Fe, and the calcium silicate insulation materials were mainly consisted of Al, Si, Ca, and Fe.
본 연구에서는 실리카흄 대체재로 활용 가능한 실리카 흄 무혼입 결합재(SFFB)의 치환율에 따른 고강도 콘크리트의 품질특성을 비교․분석하기 위하여, 실리카흄, SFFB의 2수준과 물-결합재비는 25, 35% 치환율은 실리카 흄 10%, SFFB 5, 10 15(%)의 4수준으로 설정하였다. 실험을 실시한 결과, 목표 유동성을 확보하기 위한 고성능감수제의 첨가율은 물-결합재비가 낮을수록 증가하였으며, SFFB가 실리카 흄 보다 저흡수성을 갖는 재료적 특성으로 인해 고성능감수제의 첨가율이 감소하는 경향을 나타내었다. 압축강도에서는 SFFB 치환율이 10%일 경우 인장강도에서는 치환율이 15%일 경우 가장 우수한 강도를 나타내었으며, 자기수축에서는 W/B와 SFFB의 치환율과 상관없이 Plain(SF)에 비해 수축이 저감하는 것으로 나타났다.