• Nuclear Engineering and Technology
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• 제56권2호
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• pp.707-714
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• 2024

Different degrees of natural radioactivity found in quartz can have negative consequences on health. Quartz vein along the investigated Abu Ramad area, Egypt, had its natural radioactivity assessed. The HPGe spectrometer was used to determine the role played by the radionuclides ²³⁸U, ²³²Th, and ⁴⁰K in the gamma radiation that was emitted, and the results showed that these concentrations are 484.64 ± 288.4, 36.8 ± 13.1 and 772.2 ± 134.6 Bq kg^-1 were higher than the corresponding reported global limits of 33, 45, and 412 Bq kg^-1 for each radionuclide (²³⁸U, ²³²Th, and ⁴⁰K). Among the radiological hazard parameters, the excess lifetime cancer risk (ELCR) is estimated and it's mean value of ELCR (1.2) is higher than the permissible limit of 0.00029. The relationship between the radionuclides and the associated radiological hazard characteristics was investigated based on multivariate statistical methods including Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA). According to statistical research, the radioactive risk of quartz is primarily caused by the ²³⁸U, ²³²Thand ⁴⁰K. Finally, applying quartz to building materials would pose a significant risk to the public.

• 대한환경공학회지
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• 제34권8호
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• pp.517-522
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• 2012

본 연구에서는 오 폐수의 처리에 있어서 천연제올라이트 및 맥반석을 활용하여 오 폐수의 응집 및 흡착 메커니즘에 적용하여 수처리제로서의 타당성을 검토하고자 하였다. Jar test를 이용한 응집 전 후의 $COD_{Cr}$의 제거율을 평가하였다. 맥반석과 천연제올라이트를 수처리제로써 주입량을 400~1,200 g/L로 변화시켜 처리한 결과 $COD_{Cr}$ 최종제거율은 별 차이를 보이지 않았으나, 맥반석과 천연제올라이트를 $600^{\circ}C$로 소결하여서 도시하수를 처리할 경우 $COD_{Cr}$제거율이 각각 15%, 3%정도 상승하였다. 또한 맥반석과 천연제올라이트를 혼합하여 미용화장지 폐수처리에 적용하였으며, 또 다른 폐수처리제로서의 가능성을 검토하였다.

• 한국산학기술학회논문지
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• 제4권1호
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• pp.27-30
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• 2003

자수정은 우리나라에서 산출되어 수출시장이 큰 준보석이다. 원석을 가공하여 최종 장신구제품을 제작하는데 실제 원석에서는 연수정, 자수정, 백수정이 함께 산출되어 이들의 품위를 정량적으로 평가하여 원석가격을 산출하는 것과 아직 확보되지 않은 자수정의 정량적 감정 기술이 필요하다. 이제까지는 아쉽게도 육안 판별과 경험에 의존하였으나 투과전자 현미경과 진동시편자력계측정을 통하여 3가지 원석의 특성을 명확히 구별하는 것이 가능하였다. 또한 FTIR(Fourier transformation infra-red) 측정을 통하여 고가 자수정의 정량품질 확인도 가능하였다. 이러한 방법은 원석의 품위를 확인하는데 효과적이고 최초 원석 상태에서의 고가 자수정의 함량을 평가할 수 있는 우수한 지표가 될 수 있었다.

• 한국결정성장학회지
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• 제13권1호
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• pp.41-45
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• 2003

FT-IR은 보석을 감별하고 연구하는데 있어서 아주 유용한 장비이다. 그러므로 본 연구에서는 FT-IR을 이용하여 자수정. 황수정, 백수정 그리고 비취를 감별하는 데에 중점을 두었다 FT-IR은 자수정, 황수정과 백수정의 천연과 합성의 진위를 가리는데 매우 효과적이었으며, 천연 비취(A-Jade)와 왁스가 주입된 비취, 폴리머가 주입된 비취(B-Jade)를 식별하는 데 매우 유용하였다. 이러한 기술은 처리와 합성에 의해 새롭게 변화되어 나타나는 보석의 감별에 있어, 결정적으로 도움이 될 것이다.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.2025-2037
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• 2021

The influence of lead cations on natural quartz (QZ) from Egypt as a glass shielding material for the composition with nominal formula (10Na₂O - (90 - x) QZ - xPbO (where x = 30, 35, 40, 45 and 50 mol %)) was examined. The studied samples are synthesized via the melt quenching method at 1050 ℃. The X-ray diffraction XRD patterns were confirmed the glass nature for studied samples. Moreover, the optical properties, and the transparency for all compositions were examined by UV-Vis spectroscopy. Also, the major elemental composition of the natural quartz were estimated via the X-ray fluorescence (XRF) technique. Further, the density and molar volume were determined. Furthermore, the nuclear shielding parameters such as, mass attenuation coefficient, effective atomic number, electronic density, the total atomic, and electronic cross sections as well as the mean free path, and the half value layer with different gamma ray energies (81 keV-1407 keV) were calculated. Besides, the results showed that the shielding behavior towards the gamma ray radiation for all glass samples was increased as the increment in PbO concentration in the glass system.

• Applied Biological Chemistry
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• 제14권3호
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• pp.183-189
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• 1971

규산재료(珪酸材料)인 강사(江砂) 및 석영(石英)과 농용(農用) 소석회(消石灰)의 혼합(混合) 용융물(溶融物)에 대(對)한 규산질(珪酸質) 비료(肥料)로써의 효과(效果)를 구명(究明)코져 유효규산함량(有效珪酸含量)이 낮은 답토괴(畓土壞)에서 수도(水稻)에 대(對)해서 천연(天然) 규회석(珪灰石)을 대조(對照)로 시비처리(施肥處理)하여 시험(試驗)한 결과(結果) 1. 모래용융물(溶融物)이 석영용융물(石英溶融物)에 비(比)하여 N/2 염산가용규산함량(鹽酸可溶珪酸含量)이 높고 2% 구연산 가용규산함량(可溶珪酸含量)은 석영용융물(石英溶融物)이 모래용융물(溶融物)보다 높았다. 2. 벼의 규산흡수량(珪酸吸收量)은 석영용융물(石英溶融物)에서 가장 크고 모래용융물(溶融物)과 규회석(珪灰石)은 거의 같았으며 이용율(利用率)은 천연(天然) 규회석(珪灰石)이 가장 높고 석영용융물구(石英溶融物區)가 모래용융물구(溶融物區)보다 높았다. 3. 정조수량(正租收量)은 규산물질(珪酸物質)의 시용(施用)으로 수량구성요소중(收量構成要素中) 수당입수(穗當粒數), 등숙률(登熟率) 및 천입중(千粒重)의 증가(增加)로 증수(增收)되었으며 공시재료중(供試材料中) 석영용융구(石英溶融區)에서 가장 크게 증수(增收)하였으며 대조구(對照區)${\fallingdotseq}$모래용융물(溶融物) 100kg/10a<천연규회석(天然珪灰石)${\fallingdotseq}$모래용융물(溶融物) 300kg/10a${\fallingdotseq}$석영용융물(石英溶融物) 100kg/10a<모래용융물(溶融物) 500kg/10a${\fallingdotseq}$석영용융물(石英溶融物) 300kg/10a<석영용융물(石英溶融物) 500kg/10a의 순서(順序)이었다.

• 대한전자공학회논문지
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• 제13권3호
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• pp.11-15
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• 1976

한국산 천연수정은 보석장식용으로서는 그 품질이 이미 알려져 있으나 수정진동자로서의 특성에 관해서는 아직 보고된 바가 없다. 본 연구는 특히 경상도일대에서 채굴되고 있는 천연수정을 채집, 선별, 가공하여 그 수정진동자로서의 사용가능성을 실험을 통하여 검토한 것이다. 필자들은 채굴현장 근처에서 채집한 원석을 특별히 고안제작된 검사경을 이용하여 분석선별하였으며 X-ray를 사용하여 AT-cut로 orientation 한후 시판을 절단하였다. 다음 적용하여 전기적, 광학적 쌍수상태를 검토하고 다시 선별하였다 Dimensioning은 5MHz를 목표로 하였는데 연잠제를 사용하여 5MHz의 조도까지 연마하고 전극으로서 표준형의 은막을 부착하여 시판을 완성하였다. 시판을 대한 측정결과는 모든 등가정수가 대표적인 수입수정판의 것과 대등하였으며 특히 Q는 모두 105를 넘었다. 온도특성도 AT-cut의 이론치와 대차가 없었으며 -20℃-+100℃ 범위에서 최대 20PPM 이내의 편차를 보였다. 즉, 한국산 천연수정은 적절히 선별, 가공 한다면 부유한 수정진동자의 원재로서 사용할수 있음이 증명되었다. Samples of domestic natural quartz were collected and screened optically and chemically, and, after weeding out portions unfit for electrical resonator, were cut into AT-cut wafers, which in turn were dimensioned, trimmed and lapped into 5MHz resonator units. The results of measurements obtained from the specimens indicated excellent electrical characteristics of domestic natural quartz with the average Q quotient of 10s or higher. Temperature characteristics also showed typical AT-cut corves with the frequency deviation of 20PPM at maximum throughout the range of -20 to 100℃. The experiment on the initial batch of samples amply indicates the excellent electrical quality of domestic natural quartz as quartz resonator units.

• 지구물리
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• 제7권2호
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• pp.113-120
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• 2004

Hydrochemical characteristics of deep groundwater at Surak-ri, Nonsan-gun, Chungnam Province was explained by major ion concentration, water type, and phase stability diagram. The area is composed of meta-sedimentary rock and quartz pophyry. The 5 boreholes where deep groundwater was sampled and analyzed are located on the meta-sedimentary rocks and drilling depth range of the wells is from 554 m to 928 m. pH, TDS, Na, and SiO2 values are high in the groundwater from meta-sedimentary area intruded by quartz pophyry, while Ca is high in the groundwater from meta-sedimentary area. K and Mg concentrations are low but F concentration is high both groundwater. The content of major anions is in the order of CO3(HCO3)>Cl>SO4(F) in both geology, while that of major cations shows the order of Na>Ca>K(Mg) in meta-sedimentary area intruded by quartz porphyry and a>Na>Mg>Na in meta-sedimentary area. Based on the phase equilibrium in the systems Na2O-Al2O3-SiO2-H2O and K2O-Al2O3-SiO2-H2O, the groundwater is saturated with respect to Quartz and more evolved compared with the natural mineral water. It is concluded that chemical evolution in the groundwater from meta-sedimentary area intruded by quartz porphyry, is nearly saturated with respect to feldspar, while the groundwater from meta-sedimentary area continue to proceed with increasing pH by reaction of feldspar.

• 자원환경지질
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• 제25권3호
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• pp.297-316
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• 1992

The Daebong gold-silver deposits is located in 8 km southwest of Cheongyang, Chungcheongnam-Do, Republic of Korea. The gold-silver-bearing hydrothermal quartz veins was formed within the Precambrian metasediments of Gyeonggi massif. Ore minerals occur as mainly of pyrite, sphalerite (0.78~6.19 wt.% Cd), galena, pyrrhotite and minor amounts of chalcopyrite, arsenopyrite, magnetite, ilmenite, chalcocite, electrum (55.00~89.55 wt.% Au) and argentite. The gangue minerals are quartz, calcite, chlorite, K-feldspar, biotite. Wall-rock alterations such as chloritization, silicification, pyritization, carbonatization and sericitization can be observed near the quartz veins. According to the mineral paragenetic sequence based on vein structure and mineral assemblages, three stage mineralizations can be recognized. Fluid inclusion, sulfur isotope and thermodynamic data show that the ore minerals were dominantly deposited at the between 388 and $204^{\circ}C$ from fluids with salinities of 8.1~0.3 wt.% equivalent NaCl, and sulfur isotope value 4.84 to 6.40 per mil of sulfides indicates igneous sources of sulfur in the hydrothermal system and fluid inclusion salinity data suggest that thermal fluids may have magmatic origin with some degree mixing of meteoric water.

• 자원환경지질
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• 제27권6호
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• pp.537-548
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• 1994

The Weolyu gold-silver deposits at Hwanggan, Chungcheongbukdo, is of a late Cretaceous $(74.24{\pm}1.63Ma)$ epithermal vein-type, and is hosted in the quartz porphyry of late Cretaceous age. Based on mineral paragenetic sequence interpreted from vein structure and mineral assemblages, three stages mineralization were distinguished. A variety of ore minerals occurs including pyrite, sphalerite, chalcopyrite, galena with small amount of electrum, native silver, argentite, pearceite, sb-pearceite, argyrotite. The gangue minerals are quartz, rutile, calcite, apatite, fluorite and rhodochrocite. Wall-rock alteration such as pyritization, chloritization, sericitization, silicification is observed near the quartz veins. Au-Ag minerals were crystallized at middle and late stage of the two mineralization sequences. Results from the analysis of fluid inclusion and thermodynamic calculation indicate that Au-Ag mineral deposits were formed primarily by cooling and dilution of hydrothermal fluids($165{\sim}313^{\circ}C$, 0.4~2.4wt.% equivalent NaCl) with some degree mixing of meteoric water.