• Title/Summary/Keyword: Properties of substances

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A Understanding of Dietary Supplements and Functional Foods in the Occident (서양의 식이보충제와 기능성 식품에 대한 인식)

  • Seo, Min-Jun;Park, Jin-Han
    • The Journal of Dong Guk Oriental Medicine
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    • v.11
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    • pp.41-51
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    • 2008
  • Dietary supplements are used by more than one-half of the adult US population. By contrast, herbal products in Germany are carefully regulated by the same standards as drugs, and efforts are under way to standardize their regulation in the entire European Union. Most herbal users do not inform their physicians that they are taking these supplements, and most physicians do not inquire. Although some herbal products have clinically proven benefits, it is increasingly apparent that many contain potentially toxic substances, particularly in relation to interactions with drugs. Hence, it is essential that practicing physicians develop a working knowledge of herbals-specifically, about claims for their usage and potential or proven efficacies and toxicities-and that they incorporate such knowledge into the evaluation and management of their patients. By contrast, functional foods-integral components of the diet that are understood to contribute added health benefits-are the subject of intense and widespread research in food and nutritional science. Examples include many polyphenolic substances, carotenoids, soy isoflavones, fish oils, and components of nuts that possess antioxidant and other properties that decrease the risk of vascular diseases and cancer. Practicing physicians are advised to stay abreast of these emerging findings in order to best advise their patients on the value of health-promoting diets in disease prevention.

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Fine Dust Adsorption of Cement Matrix Using Sepiolite (세피올라이트를 활용한 시멘트 경화체의 미세먼지 흡착 특성 )

  • Jeon, Eun-Yeong;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.71-72
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    • 2023
  • As industrialization and urbanization accelerate, environmental issues have moved from local concerns to global issues. Among them, air pollution is the most important issue. Modern people spend more than 88% of their day indoors, but the concentration of fine dust and pollutants flowing indoors is increasing. The indoor environment has its own complexity, and various substances used indoors, such as building materials, furniture, electronics, and cleaning agents, emit chemical substances and cause various diseases. Therefore, when selecting building materials and interior finishing materials, the pollutant emission and adsorption capacity must be greatly considered. These considerations will ensure the construction of a sustainable future environment and a healthy life within that environment. Therefore, in order to reduce the generation of indoor air pollutants, this study aims to examine the fine dust adsorption properties of cement hardening materials using sepiolite, which has a porous structure and high absorption power among clay minerals. As a result of the experiment, it was found that the concentration of fine dust decreased as the addition rate of sepiolite increased. It is believed that the fine dust concentration was reduced due to the high porosity due to the microfibrous structure and large specific surface area of sepiolite, which has a porous structure among clay minerals. It is believed that these experimental results can be used as basic research for future use of sepiolite as a construction material.

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Effects of EPS on membrane fouling in a hybrid membrane bioreactor for municipal wastewater treatment

  • Zhang, Aining;Liu, Zhe;Chen, Yiping;Kuschk, Peter;Liu, Yongjun
    • Membrane and Water Treatment
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    • v.5 no.1
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    • pp.1-14
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    • 2014
  • A pilot-scale hybrid membrane bioreactor (HMBR) for real municipal wastewater treatment was developed by adding biofilm carriers into a conventional membrane bioreactor, distribution and dynamic changes of the extracellular polymeric substances (EPS) and their roles in membrane fouling were investigated. The results showed that the concentrations of loosely bond EPS (LB-EPS) and tightly bond EPS (TB-EPS) in activated sludge, carrier biofilm and sludge cake layer have been increased significantly with the running time of HMBR, during operation of the HMBR, EPS demonstrated positive correlations with membrane fouling. Compared to TB-EPS, LB-EPS showed more significant correlations with sludge physical properties and specific resistance to filtration (SRF) in HMBR, and thus demonstrated that LP-EPS have a stronger potential of fouling than TB-EPS. It was also found that a lower organic loading in HMBR could result a significant increase in EPS concentration, which would in turn influence membrane fouling in HMBR. This critical investigation would contribute towards a better understanding of the behavior, composition and fouling potential of EPS in HMBR operation.

Marine Sponges as a Drug Treasure

  • Anjum, Komal;Abbas, Syed Qamar;Shah, Sayed Asmat Ali;Akhter, Najeeb;Batool, Sundas;Hassan, Syed Shams ul
    • Biomolecules & Therapeutics
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    • v.24 no.4
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    • pp.347-362
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    • 2016
  • Marine sponges have been considered as a drug treasure house with respect to great potential regarding their secondary metabolites. Most of the studies have been conducted on sponge's derived compounds to examine its pharmacological properties. Such compounds proved to have antibacterial, antiviral, antifungal, antimalarial, antitumor, immunosuppressive, and cardiovascular activity. Although, the mode of action of many compounds by which they interfere with human pathogenesis have not been clear till now, in this review not only the capability of the medicinal substances have been examined in vitro and in vivo against serious pathogenic microbes but, the mode of actions of medicinal compounds were explained with diagrammatic illustrations. This knowledge is one of the basic components to be known especially for transforming medicinal molecules to medicines. Sponges produce a different kind of chemical substances with numerous carbon skeletons, which have been found to be the main component interfering with human pathogenesis at different sites. The fact that different diseases have the capability to fight at different sites inside the body can increase the chances to produce targeted medicines.

Cancer Chemoprevention by Dietary Phytochemicals: Rationale and Mechanisms (Dietary Phytochemical을 이용한 화학적 암에방과 그 작용 기전)

  • Surh, Young-Joon;Lee, Jong-Min
    • Environmental Mutagens and Carcinogens
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    • v.18 no.1
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    • pp.1-8
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    • 1998
  • Chemoprevention refers to the use of non-toxic chemical agents to prevent the neoplastic development by inhibiting, delaying, or reversing a multi-stage carcinogenesis. The primary goal of chemoprevention research is to identify or produce effective agents and strategies for clinical trials for applications to normal or high risk human populations. A large number of compounds have been tested for their possible chemopreventive activities, and it is of interest to note that many of them are naturally occurring substances. Thus, a variety of plant and vegetable constituents, particularly those included in our daily diet, have been found to possess substantial protective properties against experimental carcinogenesis. These substances, collectively known as dietary phytochemicals, exert their chemopreventive effects by influencing specific step(s) of multi-stage carcinogenesis: some inhibit metabolic activation or enhance detoxification of carcinogens, others interfere with covalent interactions between ultimate eloctrophilic carcinogens and the target cell DNA and still others may exert anti-promoting or anti-progressing effects. Mechanism-based interventions by use of safe dietary phytochemicals may provide one of the most practical and promising cancer chemopreventive strategies.

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Prediction of the Net Heats of Combustion of Organic Halogenated Compounds based on the Atomic Contribution Method (원자기여법에 근거한 유기 할로겐 화합물의 순연소열 예측)

  • Ha, Dong-Myeong;Lee, Sung-Jin
    • Fire Science and Engineering
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    • v.17 no.4
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    • pp.7-12
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    • 2003
  • The heat of combustion is one of the major physical properties used to determine the fire and explosion hazards of the flammable substances. Empirical equations have been developed to pre-dict the net heats of combustion of organic halogenated compounds based on the atomic contribution method. The method developed in this study was compared with Cardozo's method and Hanley's method. As can be seen from the average absolute deviation(A.A.D.), the proposed equation was found to be best. The proposed equation may serve as an estimation scheme for the heats of combustion of the other organic halogenated compounds.

Prediction and Measurement of Flash Point and Fire Point of Aromatic Hydrocarbons (방향족탄화수소의 인화점과 연소점 측정 및 예측)

  • Ha Dong-Myeong;Han Jong-Geun
    • Journal of the Korean Institute of Gas
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    • v.9 no.3 s.28
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    • pp.21-26
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    • 2005
  • The flash points and the fire points are one of the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable substances. In this study, the flash points of aromatic hydrocarbons, were measured by using Pensky-Martens Closed Cup apparatus(ASTM-D93) and Tag Open-Cup apparatus(ASTM D 1310-86). Also the fire points of aromatic hydrocarbons, were measured by using Tag Open-Cup apparatus. The measured flash points were in good agreement with reference values. The measured fire points compared with the estimated values based on 1.23 times stoichiometric concentration. The values calculated by the proposed equation were in agreement with measured values.

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Eco-Friendly Emissive ZnO-Graphene QD for Bluish-White Light-Emitting Diodes

  • Kim, Hong Hee;Son, Dong Ick;Hwang, Do-Kyeong;Choi, Won Kook
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.627-627
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    • 2013
  • Recently, most studies concerning inorganic CdSe/ZnS quantum dot (QD)-polymer hybrid LEDs have been concentrated on the structure with multiple layers [1,2]. The QD LEDs used almost CdSe materials for color reproduction such as blue, green and red from the light source until current. However, since Cd is one of six substances banned by the Restriction on Hazardous Substances (RoHS) directive and classified into a hazardous substance for utilization and commercialization as well as for use in life, it was reported that the use of CdSe is not suitable to fabricate a photoelectronic device. In this work, we demonstrate a novel, simple and facile technique for the synthesis of ZnO-graphene quasi-core.shell quantum dots utilizing graphene nanodot in order to overcome Cd material including RoHS materials. Also, We investigate the optical and structural properties of the quantum dots using a number of techniques. In result, At the applied bias 10 V, the device produced bluish-white color of the maximum brightness 1118 cd/$m^2$ with CIE coordinates (0.31, 0.26) at the bias 10 V.

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Simple Identification Methods for Unknown Suspicious White Powders using Microfluidic-based Platform (미세유체 기반의 플랫폼을 이용한 미지의 백색가루 간이식별 탐지방안)

  • Park, Jae Woo;Song, Jiyoung;Na, Sang Cheol;Byun, Kisik;Jeon, Noo Li
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.6
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    • pp.853-859
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    • 2017
  • Terrorists always threats the global security with the possibility of using prohibited warfare, NBCs(Nuclear, Biological and Chemical Warfare). Compared to other prohibited warfares, most of biological warfare agents (BWAs) have no physical properties and time delays from spread to affect. Therefore the early detection is important to protect and decontaminate from BWAs. On the preliminary detection stage for suspicious material, most of detection kits only serve to know weather the BWAs exists or not. Due to this reason, simple field confirmation testing for suspicious substances have been used to identify materials which show negative result on detection kits. Considering the current Lab on a Chip(LOC) technologies, we suggest simple identification platform for unknown suspicious substances based on paper fluidics. We hope that our research will envision the future direction for the specific point-of-view for LOC technologies on detection strategy of BWAs.

Evaluation of Indoor Air Improvement of Matrix Using Activated clay as Adsorption Material (활성백토를 흡착재로 활용한 경화체의 실내 공기 개선 평가)

  • Jeong, Hyun-Su;Kim, Yeon-Ho;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.189-190
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    • 2020
  • The importance of indoor air quality management has recently been highlighted due to environmental problems such as indoor air pollution. Among indoor air pollutants, carbon dioxide occurs in cooking, heating, burning, and causes forgetfulness, dementia and amnesia. Radon, which occurs in building materials, soil and ground, is a type 1 carcinogen that causes lung cancer in the body through breathing. These substances can be released from the room through ventilation, but there is a limit to reducing the amount of indoor activity due to reduced ventilation conditions due to increased indoor activity time. However, these substances can be removed from the gas by adsorption. The purpose of this study was to identify the properties of granular active and powdered active white soil and mix them to make cement-based active white soil adsorbent matrix for carbon dioxide, fine dust and radon gas adsorption, and to evaluate indoor air improvements according to the mixing scale. The results of the experiment showed that active carbon dioxide adsorption performance increased for carbon dioxide and radon as the exchange rate increased through physical adsorption. In particular, the higher the replacement rate of the granular active bag, the better adsorption performance was shown.

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