• Title/Summary/Keyword: Lead extraction

Search Result 258, Processing Time 0.023 seconds

Health Risk Assessment of Airborne Toxic Metals in Taejon Third and Fourth Industrial Complexes (대전 3, 4 공단지역의 대기중 독성금속의 인체 위해도 평가)

  • Lee, Jin-Hong;Jang, Mi-Suk;Lim, Joung-Myung;Ku, Bu-Mi
    • Journal of Environmental Impact Assessment
    • /
    • v.9 no.4
    • /
    • pp.271-276
    • /
    • 2000
  • The research centers on the health risk assessment of airborne toxic metals in Taejon third and fourth industrial complexes. Total suspended particulates were collected on glass microfibre filters by high volume air samplers. Fifteen toxic metals including 6 carcinogenic metals were analyzed by ICP-MS and ICP-AES after the pre-treatment of mixed acid extraction. The following results were summarized from the research : 1) the concentrations of TSPs were $17.7{\sim}219.6{\mu}g/m^3$ while the arithmetic mean concentration was $101.7{\mu}g/m^3$; 2) the arithmetic mean concentrations of human carcinogens such as arsenic, hexavalent chromium and nickel subsulfide were 10.22, 6.96 and 6.42 $ng/m^3$, respectively while those of probable human carcinogens such as beryllium, cadmium and lead were 0.13, 3.41, 97.65 $ng/m^3$, respectively; 3) the point risk estimate for the inhalation of carcinogenic metals was $1.5{\times}10^{-4}$, which was much higher than a risk standard of $10^{-5}$; 4) approximately 93% of the cancer risk were to the inhalation of human carcinogens, arsenic and hexavalent chromium, which should be properly managed in Taejon third and fourth industrial complexes.

  • PDF

Chemical Properties and Assessment of Immunomodulatory Activities of Extracts isolated from Broccoli (브로콜리로부터 분리한 추출물의 In vitro 면역증진 활성평가 및 화학적 특성)

  • Kwak, Bong-Shin;Park, Hye-Ryung;Lee, Sue Jung;Choi, Hyuk-Joon;Shin, Kwang-Soon
    • The Korean Journal of Food And Nutrition
    • /
    • v.30 no.6
    • /
    • pp.1140-1148
    • /
    • 2017
  • For the purpose of developing new immunomodulatory agents from broccoli, ethanol extract (BCEE), hot water extract (BCHW), and crude polysaccharide (BCCP) were isolated from broccoli, and their immunomodulatory activities and chemical properties were examined. In the in vitro cytotoxicity analysis, BCHW and BCCP did not affect the growth of tumor cells and normal cells. Murine peritoneal macrophages stimulated with BCCP showed higher production of IL-6, IL-12, and $TNF-{\alpha}$ cytokines than those stimulated with BCHW. Also, BCHW and BCCP did not show proliferation of splenic lymphocytes. In the in vitro assay for intestinal immunomodulatory activities, only BCCP enhanced GM-CSF secretion and the bone marrow cell-proliferating activity via cells in Peyer's patches at $1,000{\mu}g/mL$. Also, BCHW mainly contained 33.7% neutral sugars, such as arabinose, glucose, and galactose, and 30.7% uronic acid, and BCCP consisted of 42.6% neutral sugars, including arabinose, galactose, and glucose, and 50.5% uronic acid. The above results lead us to conclude that crude polysaccharide (BCCP) isolated from broccoli causes considerably high cytokine production in peritoneal macrophages and bone marrow cell proliferation, and the polysaccharide extraction process is indispensable for separation of new immunomodulatory agents from broccoli.

ASSESSMENT OF INFERIOR ALVEOLAR NERVE DAMAGE USING DIGITAL INFRARED THERMOGRAPHIC IMAGING (디지털 적외선 체열 검사를 사용한 하치조 신경 손상의 평가)

  • Lee, Ji-Yeon;Lee, Jae-Hoon;Kim, Chul-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.30 no.6
    • /
    • pp.488-496
    • /
    • 2004
  • Oral & Maxillofacial surgery can lead to complications that result in abnormal sensation or movement. Inferior alveolar nerve(IAN) injury can result in dysesthesia, paresthsia of the lower lip and chin, so patients presenting with IAN damage suffer from sensory loss. But diagnosis of the nerve injury is largely limited to the subjective statements made by the patient. Distribution of sympathetic nerves parallels the distribution of the somatosensory nerves. Loss of sensory tone causes a concomitant loss of sympathetic activity, resulting in vasodilation of the cutaneous blood vessels that demonstrates greater heat loss. Digital infrared thermographic imaging(DITI) detects infra-red radiation given off by body. DITI can detect minute difference in temperature from different parts of the body and translates the amount of heat into quantitative data. The area of different temperature correlated with pain or disease can be visualized by corresponding color. The objective of this study was to determine the efficacy of DITI in objectively assessing IAN injury. The 19 normal subjects and the 14 patients underwent DITI scan. The normal subjects received unilateral IAN block anesthesia with 2 ml of 2% lidocaine (IAN bolck group) to evaluate temporary alteration in nerve function. Patient group were patients with unilateral IAN damage (dysesthesia or paresthesia) after surgical treatment(Mn. 3rd molar Extraction, etc.). The surgical procedure performed within 6 months of test. The results were as follows. 1. No significant differences in temperature were found between left and right sides of the lower lip and chin in the control group. 2. Significant temperature differences were found between the anesthetized and non-anesthetized sides of the lower lip and chin in the IAN block group. 3. Significant temperature differences were found between the involved and uninvolved sides of the lower lip and chin areas of the experimental group. The results of the study show that DITI can be an useful and effective means of objectively assessing and visualizing IAN damage.

A Focused Crawler by Segmentation of Context Information (주변정보 분할을 이용한 주제 중심 웹 문서 수집기)

  • Cho, Chang-Hee;Lee, Nam-Yong;Kang, Jin-Bum;Yang, Jae-Young;Choi, Joong-Min
    • The KIPS Transactions:PartB
    • /
    • v.12B no.6 s.102
    • /
    • pp.697-702
    • /
    • 2005
  • The focused crawler is a topic-driven document-collecting crawler that was suggested as a promising alternative of maintaining up-to-date web document Indices in search engines. A major problem inherent in previous focused crawlers is the liability of missing highly relevant documents that are linked from off-topic documents. This problem mainly originated from the lack of consideration of structural information in a document. Traditional weighting method such as TFIDF employed in document classification can lead to this problem. In order to improve the performance of focused crawlers, this paper proposes a scheme of locality-based document segmentation to determine the relevance of a document to a specific topic. We segment a document into a set of sub-documents using contextual features around the hyperlinks. This information is used to determine whether the crawler would fetch the documents that are linked from hyperlinks in an off-topic document.

Monitoring Onion Growth using UAV NDVI and Meteorological Factors

  • Na, Sang-Il;Park, Chan-Won;So, Kyu-Ho;Park, Jae-Moon;Lee, Kyung-Do
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.50 no.4
    • /
    • pp.306-317
    • /
    • 2017
  • Unmanned aerial vehicles (UAVs) became popular platforms for the collection of remotely sensed data in the last years. This study deals with the monitoring of multi-temporal onion growth with very high resolution by means of low-cost equipment. The concept of the monitoring was estimation of multi-temporal onion growth using normalized difference vegetation index (NDVI) and meteorological factors. For this study, UAV imagery was taken on the Changnyeong, Hapcheon and Muan regions eight times from early February to late June during the onion growing season. In precision agriculture frequent remote sensing on such scales during the vegetation period provided important spatial information on the crop status. Meanwhile, four plant growth parameters, plant height (P.H.), leaf number (L.N.), plant diameter (P.D.) and fresh weight (F.W.) were measured for about three hundred plants (twenty plants per plot) for each field campaign. Three meteorological factors included average temperature, rainfall and irradiation over an entire onion growth period. The multiple linear regression models were suggested by using stepwise regression in the extraction of independent variables. As a result, $NDVI_{UAV}$ and rainfall in the model explain 88% and 68% of the P.H. and F.W. with a root mean square error (RMSE) of 7.29 cm and 59.47 g, respectively. And $NDVI_{UAV}$ in the model explain 43% of the L.N. with a RMSE of 0.96. These lead to the result that the characteristics of variations in onion growth according to $NDVI_{UAV}$ and other meteorological factors were well reflected in the model.

Characteristics of Icing Phenomenon with Droplet of an Injector for Liquid Phase LPG Injection System (LPG 액상분사식 인젝터에서 후적에 의한 아이싱 특성 연구)

  • Park, Cheol-Woong;Kim, Chang-Up;Choi, Kyo-Nam;Kang, Kern-Yong
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.15 no.5
    • /
    • pp.9-16
    • /
    • 2007
  • Since the liquid phase LPG injection(LPLI) system has an advantage of higher power and lower emission characteristics than the mixer type fuel supply system, many studies and applications have been conducted. However, the heat extraction, due to the evaporation of liquid fuel, causes not only a dropping of LPG fuel but also icing phenomenon that is a frost of moisture in the air around the nozzle tip. Because both lead to a difficulty in the control of accurate air fuel ratio, it can result in poor engine performance and a large amount of HC emissions. The experimental investigation was carried out on the bench test rig in this study. It was found that n-butane, that has a relatively high boiling point($-0.5^{\circ}C$), was a main species of droplet composition and also found that the droplet problem was improved by the use of a large inner to outer bore ratio nozzle whose surface roughness is smooth. The icing phenomena were decreased when the an engine head temperature was increased, although a large amount of icing deposit was still observed in the case of $87^{\circ}C$. Also, it was observed that the icing phenomenon is improved by using anti-icing bushing.

Comparison of LoG and DoG for 3D reconstruction in haptic systems (햅틱스 시스템용 3D 재구성을 위한 LoG 방법과 DoG 방법의 성능 분석)

  • Sung, Mee-Young;Kim, Ki-Kwon
    • Journal of Korea Multimedia Society
    • /
    • v.15 no.6
    • /
    • pp.711-721
    • /
    • 2012
  • The objective of this study is to propose an efficient 3D reconstruction method for developing a stereo-vision-based haptics system which can replace "robotic eyes" and "robotic touch." The haptic rendering for 3D images requires to capture depth information and edge information of stereo images. This paper proposes the 3D reconstruction methods using LoG(Laplacian of Gaussian) algorithm and DoG(Difference of Gaussian) algorithm for edge detection in addition to the basic 3D depth extraction method for better haptic rendering. Also, some experiments are performed for evaluating the CPU time and the error rates of those methods. The experimental results lead us to conclude that the DoG method is more efficient for haptic rendering. This paper may contribute to investigate the effective methods for 3D image reconstruction such as in improving the performance of mobile patrol robots.

Effects of Biochar on Soil Quality and Heavy Metal Availability in a Military Shooting Range Soil in Korea

  • Lee, Sung-Eun;Ahmad, Mahtab;Usman, Adel A.R.A.;Awad, Yasser M.;Min, Sun-Hong;Yang, Jae-E;Lee, Sang-Soo;Ok, Yong-Sik
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.44 no.1
    • /
    • pp.67-77
    • /
    • 2011
  • Heavy metal remediation in shooting range soil is a challenge over the world. The excessive Pb accumulation in the soil can deteriorate soil quality and fertility. The objectives of this research were to evaluate the efficiency of biochar (BC) in improving the physicochemical and biological properties of the soil and to evaluate its effect on Pb availability in a military shooting range soil. Sandy loam soil was collected from shooting range of Gyeonggi Province, South Korea and was incubated for 30 days with different application rates (0-30% w $w^{-1}$) of BC. The results showed that the addition of BC increased aggregate stability, nitrogen (N) and phosphorus (P) contents, and enzyme activities in soil. Sequential extraction showed that residual and organic bound fractions in the soil amended with BC increased by 33.1 and 16.7%, respectively, and the exchangeable fraction decreased by 93.7% in the soil amended with BC, compared to the unamended soil. We concluded that the application of BC could not only improve physicochemical and biological soil qualities but also stabilize Pb in a shooting range soil.

CONSERVATIVE TREATMENT OF DENTIGEROUS CYSTS ; 5 CASES (소아에서 발생한 함치성 낭종의 보존적 치료의 치험례 ; 5 례)

  • Jun, Chang-Hun;Jeong, Jong-Cheol;Song, Min-Seok;Seo, Ji-Hoon;Kim, Sung-Beom;Choi, Se-Hoon;Kim, Hyeon-Min
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.29 no.2
    • /
    • pp.135-139
    • /
    • 2003
  • A dentigerous cyst is an epithelium-lined sac that surrounds the crown of an unerupted tooth or odontoma. And the most common sites of this cyst are the mandibular and maxillary third molar and maxillary cuspid a areas. Clinically, expansion of bone with subsequent facial asymmetry, extreme displacement of teeth, severe root resorption of adjacent teeth and pain are all possible sequelae of this cyst. The standard treatment for a dentigerous cyst is enucleation and extraction of the involved tooth. But in large cysts, this can lead to functional, cosmetic and psychologic consequences to the patients. So recently, more conservative methods are used. We report 5 cases of dentigerous cysts in pediatric patient which were treated by a conservative approach, By this methods, we can preserve teeth and guide eruption of the teeth which are involved in cystic area.

Determination of a Trace Amount of Copper, Lead, Cadmium and Zinc in Water by Solvent Extraction and Square Wave Polarography (溶媒抽出-矩形波폴라로그래피에의 물중의 미량 구리, 납, 카드뮴 및 아연의 定量)

  • Moon Su-Chan
    • Journal of the Korean Chemical Society
    • /
    • v.21 no.5
    • /
    • pp.372-378
    • /
    • 1977
  • The following new techniques have been developed: (A); To a 500ml of sample water, it was adjusted pH 10 with ammonia-anmonium citrate, added 10ml of 1${\%}$ sodium diethyldithiocarbamate and extracted three times with 10ml of CHCl3. The extract was shaken with 10ml of 0.05N $HCl-4{\times}10^{-4}M\;HgCl_2$. The aqueous solution was added 2ml of 2N KCl and washed two times with 10ml of pure $CHCl_3$, and then recorded square wave polarograms. (B); To a 500ml of sample water adjusted pH 10 with ammonia-ammonium citrate, it was added 2ml of 1${\%}$ 8-hydroxyquinoline and extracted three times with 10ml $CHCl_3$. The separated $CHCl_3$ phase was shaken with 10ml of 0.2 N HCl. The aqueous solution was recorded polarograms directly. These methods can be used for determination of the ppb order of metal in water with an error of ${\pm}10{\%}$. The method (B) can not be used for the determination of zinc on account of the free 8-hydroxyquinoline.

  • PDF