• Title/Summary/Keyword: reducing

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Optimization for Enzymatic Hydrolysis of Mannitol (만니톨의 효소 가수분해 반응 조건 최적화)

  • Park, Eun-Young;Kim, Yong-Jin;Jeong, Seung-Mi;Lee, Dong-Hoon
    • KSBB Journal
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    • v.28 no.2
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    • pp.65-73
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    • 2013
  • This study aimed to investigate the enzymatic hydrolysis of mannitol using Viscozyme$^{(R)}$ L, Celluclast$^{(R)}$ 1.5 L, Saczyme$^{(R)}$, Novozym$^{(R)}$, Fungamyl$^{(R)}$ 800 L, Driselase$^{(R)}$ Basidiomycetes sp., and Alginate Lyase, and to optimize of reaction conditions for production of reducing sugar. Response surface methodology (RSM) based on central composite rotatable design was used to study effects of the independent variables such as enzyme (1-9% v/w), reaction time (10-30 h), pH (3.0-7.0) and reaction temperature ($30-70^{\circ}C$) on production of reducing sugar from mannitol. The coefficient of determination ($R^2$) of $Y_1$ (yield of reducing sugar by Viscozyme$^{(R)}$ L) and $Y_3$ (yield of reducing sugar by Saczyme$^{(R)}$) for the dependent variable regression equation was analyzed as 0.985 and 0.814. And the p-value of $Y_1$ and $Y_3$ showing 0.000 and 0.001 within 1% (p < 0.01), respectively, was very significant. The optimum conditions for production of reducing sugar with Viscozyme$^{(R)}$ L were 9.0 % (v/w) amount of enzyme, 30.0 hours of reaction time, pH 4.5 and $30.0^{\circ}C$ of reaction temperature, and those with Saczyme$^{(R)}$ were 9.0% (v/w) of amount of enzyme dosage, 30.0 h of reaction time, pH 7.0 and $30.0^{\circ}C$ of reaction temperature, consequently, the predicted reducing sugar yields were 22.5 and 27.9 mg/g-mannitol, respectively.

The Effectiveness of Non-pharmacological Interventions on Anxiety in Children Undergoing Surgery: A Systematic Review and Meta-analysis (수술 환아의 불안에 적용한 비약물적 중재의 효과: 체계적 문헌고찰 및 메타분석)

  • Kim, Hyeon-Young;Shin, Sun Hwa
    • Journal of East-West Nursing Research
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    • v.27 no.1
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    • pp.1-13
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    • 2021
  • Purpose: The purpose of this study was to examine the effectiveness of non-pharmacological interventions for reducing perioperative anxiety in children undergoing surgery. Methods: A systematic review of randomized controlled trials (RCTs) with the primary outcome of children's perioperative anxiety was conducted. The literature search was performed using various databases, including Cochrane Library, CINAHL, EMBASE, PubMed, and Korean electronic databases with confined to RCTs between 2000 and 2020. A total of sixteen studies were suitable the inclusion criteria and were systematically reviewed. The bias risk of randomized studies was evaluated using Cochrane's risk of bias tool. For the meta-analysis, RevMan 5.4 was used to analyze effect sizes of interventional factors. Results: Finally, twelve RCTs studies were used for meta-analysis. The non-pharmacological interventions implemented to reduce perioperative anxiety in children were therapeutic play, clown therapy and information provision. First, therapeutic play had a significant effect on reducing preoperative anxiety, with an effect size of -1.46 (95% CI=-1.78~-1.14). Second, clown therapy had a significant effect on reducing preoperative anxiety, with an effect size of -0.97 (95% CI=-1.45~-0.49). Finally, the provision of information had a significant effect on reducing preoperative anxiety, with an effect size of -0.75 (95% CI=-0.99~-0.51). Conclusion: This meta-analysis suggests that non-pharmaceutical interventions provide effective methods of reducing perioperative anxiety in children. Therefore, the findings verify evidence that various non-pharmacological interventions are effective means for reducing children's preoperative anxiety.

Alkaline Peroxide Pretreatment of Waste Lignocellulosic Sawdust for Total Reducing Sugars

  • Satish Kumar Singh;Sweety Verma;Ishan Gulati;Suman Gahlyan;Ankur Gaur;Sanjeev Maken
    • Korean Chemical Engineering Research
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    • v.61 no.3
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    • pp.412-418
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    • 2023
  • The surge in the oil prices, increasing global population, climate change, and waste management problems are the major issues which have led to the development of biofuels from lignocellulosic wastes. Cellulosic or second generation (2G) bioethanol is produced from lignocellulosic biomass via pretreatment, hydrolysis, and fermentation. Pretreatment of lignocellulose is of considerable interest due to its influence on the technical, economic and environmental sustainability of cellulosic ethanol production. In this study, furniture waste sawdust was subjected to alkaline peroxide (H2O2) for the production of reducing sugars. Sawdust was pretreated at different concentrations from 1-3% H2O2 (v/v) loadings at a pH of 11.5 for a residence time of 15-240 min at 50, 75 and 90 ℃. Optimum pretreatment conditions, such as time of reaction, operating temperature, and concentration of H2O2, were varied and evaluated on the basis of the amount of total reducing sugars produced. It was found that the changes in the amount of lignin directly affected the yield of reducing sugars. A maximum of 50% reduction in the lignin composition was obtained, which yielded a maximum of 75.3% total reducing sugars yield and 3.76 g/L of glucose. At optimum pretreatment conditions of 2% H2O2 loading at 75 ℃ for 150 min, 3.46 g/L glucose concentration with a 69.26% total reducing sugars yield was obtained after 48 hr. of the hydrolysis process. Pretreatment resulted in lowering of crystallinity and distortion of the sawdust after the pretreatment, which was further confirmed by XRD and SEM results.

Shrinkage Properties of High Performance Concrete Used Expansive Additive and Shrinkage Reducing Agent (팽창재와 수축저감제를 사용한 고성능 콘크리트의 수축 특성)

  • Koh, Kyung Taek;Park, Jung Jun;Ryu, Gum Sung;Kang, Su Tae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4A
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    • pp.787-794
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    • 2006
  • Generally, high performance concrete has characteristics such as low water-cementitious material ratio, lots of unit binder powder, thus the heat of hydration, autogenous shrinkage are tend to be increased. This study is to investigated the effect of the expansive additive and shrinkage reducing agent on the shrinkage properties of high performance concrete as a study to develop the reduction technology of the concrete shrinkage. Test results showed that the expansive additive and shrinkage reducing agent were effective the reduction of shrinkage of high performance concrete. Especially, the using method in combination with expansive additive and shrinkage reducing agent was more effective than the separately using method of that. Also, it analyzed that the combination of expansive additive of 5% and shrinkage reducing agent of 1% was the most suitable mixture, considering to the fluidity, strength and shrinkage properties.

Fundamental and Shrinkage Properties of High Performance Concrete in Combined with Expansive Additive and Shrinkage Reducing Agent (팽창재와 수축저감제를 조합 사용한 고성능콘크리트의 기초물성 및 수축특성)

  • Han Cheon-Goo;Kim Sung-Wook;Koh Kyoung-Taek;Cheol Han-Min
    • Journal of the Korea Concrete Institute
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    • v.16 no.5 s.83
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    • pp.605-612
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    • 2004
  • This study investigated the fundamental properties and shrinkage properties of high performance concrete with water/binder ratio of 0, 30 and with combination of expansive additive and shrinkage reducing agent. According to the results, the fluidity of high performance concrete showed lower the using method in combination with expansive additive and shrinkage reducing agent than the separately using method of that, so the amount of superplasticizer increased when the adding ratio of expansive additive and shrinkage reducing agent increased. However the air content of concrete increased when used in combination with expansive additive and shrinkage reducing agent, so the amount of AR agent decreased. The compressive strength showed the highest at $5\%$ of expansive additive, and decreased with an increase of the amount of shrinkage reducing agent. Furthermore, in order to reduce the shrinkage of high performance concrete, it was found that the using method in combination with expansive additive and shrinkage reducing agent was more effective than separately using method of that. Therefore, it analyzed that the combination of expansive additive of $5\%$ and shrinkage reduction agent of $1\%$ was the most suitable mixture, considering to the fluidity, strength and shrinkage under the condition of this experiment.

A Study on Viscosity Reducing of Cement-Based Materials by Replacing Byproducts and Adding Low-Viscosity Type HRWR (산업부산물 치환 및 저점도형 고성능 감수제를 사용한 시멘트 계열 재료의 점도저하 방안 연구)

  • Son, Bae-Geun;Han, Dongyeop
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.4
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    • pp.353-358
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    • 2017
  • The aim of this research is providing a fundamental idea on reducing viscosity of high performance cementitous materials. In rheological aspect, to determine the fluidity of the cementitious materials, both yield stress and viscosity should be controlled. For the high performance cementitious materials with low water-to-binder ratio and high volume fraction, it was difficult to reduce the viscosity with superplasticizer while reducing yield stress was relatively easy. Hence, in this research, with the goal of reducing viscosity of the cementitious materials, both ways of reducing viscosity were suggested: achieving proper combination of powder conditions, and adding low-viscosity typed water reducer. First, by replacing various byproduct powders, specifically, raw coal ash and wasted limestone powder showed favorable results on reducing viscosity of the cement paste. Regarding the low viscosity typed superplasticizer, it showed a good performance on reducing viscosity comparing with generic superplasticizer. Therefore, based on the results of this research, it is expected to provide a fundamental idea on reducing viscosity of cementitious materials by various methods.

Current status, perception and practicability of restaurant staffs related to reducing sodium use in Seongnam, Korea (성남 지역 외식업소의 나트륨 저감화 현황과 종사자의 저감화 실행에 대한 인식 및 실천용이도)

  • Ahn, So-Hyun;Kwon, Jong Sook;Kim, Kyungmin;Lee, Yoonna;Kim, Hye-Kyeong
    • Journal of Nutrition and Health
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    • v.52 no.5
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    • pp.475-487
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    • 2019
  • Purpose: With the increase of going out to eat, reducing the sodium in restaurant foods has a crucial impact on reducing sodium intake. This study aimed to assess the current status and perceptions of restaurant staffs related to reducing sodium use in restaurants. Methods: Restaurant managers and chefs (n = 312) in Seongnam area completed a questionnaire on the current status related to sodium use, the barriers to practice for reducing sodium use, support needs, and the practicability of methods for reducing sodium use in restaurants. Results: The percentage of restaurants in the preaction stage (including the precontemplation, contemplation, and preparation stages) for reducing sodium use was 79.7%. Logistic regression analysis showed that measuring salinity while cooking was associated with measuring seasoning (OR, 4.761; 95% CI, 2.325 ~ 9.751), action/maintenance stages of behavior change (OR, 2.829; 95% CI, 1.449 ~ 5.525) and providing salinity information of restaurant foods (OR, 6.314; 95% CI, 2.964 ~ 13.45). Maintaining taste and hindering the cooking process were the main barriers to reduce sodium use. The total practicability of actions for reducing sodium was higher in staffs who worked in restaurants that measured seasoning and salinity while cooking (p < 0.05 and p < 0.01, respectively). The hardest item to practice was 'purchase foods after comparing sodium content in the nutrition labeling'. 'Avoid serving salt-fermented foods as side dishes', 'serve small portions of kimchi and less salty kimchi', and 'put up promotional materials for reducing sodium intake' were selected as easy items to perform. The majority (82%) was willing to reduce sodium in restaurant foods under the support of local government and they desired the promotion of participating restaurants and education on cooking skills to reduce sodium. Conclusion: Measuring seasoning and salinity while cooking is a meaningful practice that is associated with stages of behavior change and the practicability of actions for reducing sodium. It is necessary to provide support and education with a gradual approach to staffs for reducing sodium in restaurant foods.