• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.133-133
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• 1998

In the thin film alloy formation of the transition metals ion-beam-mixing technique forms a metastable structure which cannot be found in the arc-melted metal alloys. Sppecifically it is well known that the studies about the electronic structure of ion-beam-mixed alloys pprovide the useful information in understanding the metastable structures in the metal alloy. We studied the electronic change in the ion-beam-mixed ppt-Ct alloys by XppS and XANES. These analysis tools pprovide us information about the charge transfer in the valence band of intermetallic bonding. The multi-layered films were depposited on the SiO2 substrate by the sequential electron beam evapporation at a ppressure of less than 5$\times$10-7 Torr. These compprise of 4 ppairs of ppt and Cu layers where thicknesses of each layer were varied in order to change the alloy compposition. Ion-beam-mixing pprocess was carried out with 80 keV Ae+ ions with a dose of $1.5\times$ 1016 Ar+/cm2 at room tempperature. The core and valence level energy shift in these system were investigated by x-ray pphotoelectron sppectroscoppy(XppS) pphotoelectrons were excited by monochromatized Al K ａ(1486.6 eV) The ppass energy of the hemisppherical analyzer was 23.5 eV. Core-level binding energies were calibrated with the Fermi level edge. ppt L3-edge and Cu K-edge XANES sppectra were measured with the flourescence mode detector at the 3C1 beam line of the ppLS (ppohang light source). By using the change of White line(WL) area of the each metal sites and the core level shift we can obtain the information about the electrons pparticippating in the intermetallic bonding of the ion-beam-mixed alloys.

• 한국세라믹학회지
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• 제52권4호
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• pp.229-233
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• 2015

Currently, the majority of commercial white LEDs are phosphor converted LEDs made of a blue-emitting chip and YAG yellow phosphor dispersed in organic silicone. However, silicone in high-power devices results in long-term performance problems such as reacting with water, color transition, and shrinkage by heat. Additionally, yellow phosphor is not applicable to warm white LEDs that require a low CCT and high CRI. To solve these problems, mixing of green phosphor, red phosphor and glass, which are stable in high temperatures, is common a production method for high-power warm white LEDs. In this study, we fabricated conversion lenses with LUAG green phosphor, SCASN red phosphor and low-softening point glass for high-power warm white LEDs. Conversion lenses can be well controlled through the phosphor content and heat treatment temperature. Therefore, when the green phosphor content was increased, the CRI and luminance efficiency gradually intensified. Moreover, using high heat treatment temperatures, the fabricated conversion lenses had a high CRI and low luminance efficiency. Thus, the fabricated conversion lenses with green and red phosphor below 90 wt% and 10 wt% with a sintering temperature of $500^{\circ}C$ had the best optical properties. The measured values for the CCT, CRI and luminance efficiency were 3200 K, 80, and 85 lm/w.

• 한국농공학회지
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• 제16권1호
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• pp.3225-3262
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• 1974

The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

• KSBB Journal
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• 제29권6호
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• pp.443-447
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• 2014

Biosynthesis of lactate-containing polyhydroxyalkanoates (PHAs) was examined in recombinant Escherichia coli W strain from sucrose. The Pseudomonas sp. MBEL 6-19 phaC1437 gene and the Clostridium propionicum pct540 gene, which encode engineered Pseudomonas sp. MBEL 6-19 PHA synthase 1 ($PhaC1_{Ps6-19}$) and engineered C. propionicum propionyl-CoA transferase ($Pct_{Cp}$), respectively, were expressed in E. coli W to construct key metabolic pathway to produce poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)]. The recombinant E. coli W expressing the phaC1437 gene and the pct540 gene could synthesize P(3HB-co-13mol%LA) up to the polymer content of 31.3 wt% when it was cultured in chemically defined MR medium containing 20 g/L of sucrose and 2 g/L of sodium 3-hydroxybutyrate. When Ralstonia eutropha phaAB genes were additionally expressed to provide 3-hydroxybutyrate-CoA (3HB-CoA) from sucrose, P(3HB-co-16mol%LA) could be synthesized from sucrose as a sole carbon source without supplement of sodium 3-hydroxybutyrate in culture medium, but the PHA content was decreased to 12.2 wt%. The molecular weight of P(3HB-co-16 mol%LA) synthesized in E. coli W using sucrose as carbon source were $1.53{\times}10^4$ ($M_n$) and $2.78{\times}10^4$ ($M_w$), respectively, which are not different from those that have previously been reported by other recombinant E. coli strains. Engineered E. coli strains developed in this study should be useful for the production of lactate-containing PHAs from sucrose, one of the most abundant and least expensive carbon sources.

• Journal of Ginseng Research
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• 제41권3호
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• pp.392-402
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• 2017

Background: Previously, we reported that Korean Red Ginseng inhibited liver fibrosis in mice and reduced the expressions of fibrogenic genes in hepatic stellate cells (HSCs). The present study was undertaken to identify the major ginsenoside responsible for reducing the numbers of HSCs and the underlying mechanism involved. Methods: Using LX-2 cells (a human immortalized HSC line) and primary activated HSCs, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) assays were conducted to examine the cytotoxic effects of ginsenosides. $H_2O_2$ productions, glutathione contents, lactate dehydrogenase activities, mitochondrial membrane permeabilities, apoptotic cell subpopulations, caspase-3/-7 activities, transferase dUTP nick end labeling (TUNEL) staining, and immunoblot analysis were performed to elucidate the molecular mechanism responsible for ginsenoside-mediated cytotoxicity. Involvement of the AMP-activated protein kinase (AMPK)-related signaling pathway was examined using a chemical inhibitor and small interfering RNA (siRNA) transfection. Results and conclusion: Of the 11 ginsenosides tested, 20S-protopanaxadiol (PPD) showed the most potent cytotoxic activity in both LX-2 cells and primary activated HSCs. Oxidative stress-mediated apoptosis induced by 20S-PPD was blocked by N-acetyl-$\text\tiny L$-cysteine pretreatment. In addition, 20S-PPD concentration-dependently increased the phosphorylation of AMPK, and compound C prevented 20S-PPD-induced cytotoxicity and mitochondrial dysfunction. Moreover, 20S-PPD increased the phosphorylation of liver kinase B1 (LKB1), an upstream kinase of AMPK. Likewise, transfection of LX-2 cells with LKB1 siRNA reduced the cytotoxic effect of 20S-PPD. Thus, 20S-PPD appears to induce HSC apoptosis by activating LKB1-AMPK and to be a therapeutic candidate for the prevention or treatment of liver fibrosis.

• Applied Biological Chemistry
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• 제7권
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• pp.15-19
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• 1966

유리제(製) 포장용기(包裝容器)의 질(質)이 Malathion 유제(乳劑)의 주성분(主成分) O-dimethyl S-(1, 2-dicarboxyethoxyethyl) di-thiophosphate에 미치는 경시적분해관계(輕視的分解關係)를 밝히기 위(爲)하여 각각(各各) 다른 3개회사(三個會社)에서 사용(使用)하고 있는 100 ml용(容) 갈색병(褐色甁)과 Pyrex flask를 대조(對照)로 하여 저장기간중(貯藏期間中) 용기(容器)로부터의 무기성분(無機成分)의 용출량(溶出量) pH치(値)의 변화(變化) 및 Malathion 주성분(主成分)의 분해율(分解率)을 비교(比較) 검토(檢討)하였다. 1. 공시용기(供試容器) A.B.C에다 Malathion 유제(乳劑)를 넣고 60 일(日), 120 일(日), 240 일후(日後)에 일어나는 여러가지 변화(變化)를 보았다. 2. 각기간중(各期間中)의 Si, Mg. K. Ca, Na의 용출량(溶出量)을 보면, 용기(容器)의 질(質)에 따라 각성분(各成分)의 용출량(溶出量)이 현저(顯著)히 다르고 용기(容器) A는 B,C, 보다 Na와 Ca의 용출량(溶出量)이 240 일간(日間)에 근(近) 10 배(倍)나 된다. 3. 각기간중(各期間中)의 pH 변화(變化)는 pH 6.6 에서 모두 알칼리성(性)으로 기울어지며 특히 용기(容器) A는 60 일후(日後)에 pH 9.2에 달하여 240 일후(日後)에는 9.9 까지 이른다. 그러나 Pyrex flask에서는 거의 변화(變化)가 없다. 4. Malathion의 경시변화율(輕視變化率)은 용기(容器) A에서 가장 크며 240 일후(日後)에는 7.37%나 분해(分解)된다. 그러나 pyrex flask 에서는 0.51%가 분해(分解)된다. 5. Malathion 분해율(分解率)과 동일(同一)한 질(質)의 용기(容器)에 넣어둔 물의 pH 변화(變化)와의 상관관계(相關關係)는 $r^2=0.899$ 이다. 이상(以上)의 실험결과(實驗結果)로 보아 Malathion 유제(乳劑)는 이의 용기(容器)로서 연질(軟質)인 불량(不良)한 유리병에다 저장(貯藏)하게 되면 알칼리성(性) 금속염(金屬鹽)의 용출(溶出)로 Malathion의 분해(分解)가 촉진(促進)되어 1년간(年間)에 약(約) 10나 분해(分解)됨을 알수 있다.

• Journal of Applied Biological Chemistry
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• 제59권4호
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• pp.357-360
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• 2016

국화(C. morifolium)의 꽃을 80 % MeOH 수용액으로 추출한 뒤, 감압농축한 추출물을 EtOAc, n-butyl alcohol 및 물분획으로 나누었다. EtOAc 분획과 n-butyl alcohol 분획에 대하여 $SiO_2$ 및 ODS column chromatography를 반복 실시하여 4종의 flavonoid를 분리, 정제하였다. Nuclear magnetic resonance, infrared spectrometry 및 FAB-MS data를 해석하여, 화합물 1-4를 각각 apigenin, acacetin, cosmetin (apigenin-7-O-${\beta}$-$\small{D}$-glucopyranoside), acacetin-7-O-${\beta}$-$\small{D}$-glucoside으로 구조 동정 하였다.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2000년도 학술회의 논문집 3권2호
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• pp.189-201
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• 2000

접근성이란 특정 목적을 가진 통행자가 한 지점에서 다른 지점으로 얼마나 쉽게 갈 수 있는가 를 나타내는 척도를 말한다. 따라서 접근성은 주로 공간적인 거리나 시간이 가장 중요한 요인으로 작용하며 최근에는 공간적 거리보다는 접근시간이 더 중요한 접근성 척도로 사용되고 있다. 본 연구는 GIS공간분석기법과 접근성이론을 접목하여 도시시설의 적정후보지 평가방법을 정립한 후 현재 검토되고 있는 수도권 도심공항터미널 입지 후보지 중 어떤 후보지가 이용들의 총통행시간을 최소화하는 후보 지인가에 대해 평가해보았다. 평가 결과 다음과 같은 사실을 밝힐 수 있었다. 첫째, 수도권 전체로 볼 때 평균접근시간이 가장 양호한 후보지는 쌍문터미널(현 간이 도심공항터미널)이고, 2위는 현 삼성동 도심공항터미널과 강남고속터미널, 3위는 동서울터미널과 남서울터미널 순으로 나타났다. 둘째, 수도권전체 이용자들의 총통행시간을 최소로 하는 도심공항터미널 후보지는 접근성이 가장 양호한 쌍문동터미널이 아니라 현 서울역이 1위이고, 2위는 강남고속 터미널, 3위는 용산 역으로 나타났다. 셋째, 터미널 후보지간의 가중평균접근 시간은 도심인 서울시내에 입지한 후보지와 수도권 외곽에 입지 한 후보지간에 큰 차이가 없으나 총 이용자 접근시간은 서울시에 입지한 후보지보다 외곽의 후보지가 훨씬 높게 나타나 뚜렷한 차별성을 보이고 있다. 넷째, 최적후보지 1,2,3순위 모두 서울도심과 강남도심에 입지한 지역들로 나타나 교통의 접근성 보다는 아직 인구밀집도가 주요 도시시설의 입지결정에 주요한 결정요인 되는 것으로 나타났다.해석 시스템을 구축할 예정이다. 추후에는 하수도 관망해석 컴포넌트와 하수도 업무 컴포넌트와의 통합부분에 대한 연구가 진행되어야 할 것이다.7.0로 하고 표준(標準) EDTA 용액(溶液)을 소량(少量)넣고 8N-KOH로 pH $12{\sim}13$으로 하고 N-N 희석분말(稀釋粉末)을 지시약(指示藥) 으로써 표준(標準) EDTA 용액(溶液)으로 적정(滴定)하여 Ca 치(値)를 얻었다. Ca와 Mg의 합계결정치(合計決定値)와 Ca 적정치(滴定値) 차(差)로 Mg 치(値)를 얻었다. 음(陰) ion 구분(區分)으로부터 상법(常法)에 의하여 $MgNH_4PO_4$의 침전(沈澱)을 만들어서 HCl에 녹키고 일정량(一定量)의 표준(標準) EDTA 용액(溶液)을 넣어 pH 7.0로 한다음 완충액(緩衝液)으로 pH 10으로 하고 BT 지시약(指示藥)을 써서 표준(標準) Mg $SO_4$용액(溶液)으로 적정(滴定)하여 P 치(値)를 얻었다. 본법(本法)으로 Na-phytate를 분석(分析)한 결과(結果) Na-phytate의 분자식(分子式)을 $C_6H_6O_{24}P_6Mg_4CaNa_2{\cdot}5H_2O$라고 하였을 때의 이론치(理論値)에 비(比)하여 P가 98.9% Cark 97.1%, Mg가 99.1%이고 통계처리(統計處理)한 결과분석치(結果分析値)와 이론치(理論値)는 잘 일치(一致)된다. 그러나 종래법(從來法)에 의(依)한 분석치(分析値)는 이론치(理論値)에 비(比)하여 P가 92.40%, Cark 86.80

• 한국발생생물학회지:발생과생식
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• 제13권4호
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• pp.281-289
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• 2009

이 연구는 2006년 1월부터 3월까지 전남 여수시 거문도 해역에서 어획된 찰가자미의 어미로부터 실험실 내 자연 산란을 유도하여 난발생 및 자치어 형태 발달을 관찰하였다. 수정란은 무색 투명한 분리부성란이고, 유구는 없었으며, 난경은 1.64${\pm}$0.03 mm(n=50)였다. 부화에 소요되는 시간은 수온 $9.8\sim13.0^{\circ}C$(평균 $11.4{\pm}1.6^{\circ}C$)에서 수정 후 168시간 40분이었으며, 부화 직후의 평균 전장은 4.05${\pm}$0.18 mm(n=20)였다. 부화 직후 자어는 막지느러미가 발달하였고, 물방울 모양 구조를 이루고 있으며, 입과 항문은 열려 있지 않았다. 이때 근절은 14~15+33~34=47~49개였으며, 난황은 장경이 평균 1.64${\pm}$0.12 mm, 단경은 평균 1.23${\pm}$0.19 mm였다. 부화 후 12일째 자어의 전장은 평균 7.32${\pm}$0.42 mm(n=20)로 난황은 완전히 흡수되어 후기 자어기로 이행하였고, 막지느러미 가장자리에는 별 모양 흑색 소포와 나뭇가지 모양의 황색 소포가 더욱 밀집되었고, 척색은 국화 모양의 흑색 소포가 밀집되어 4~5개의 흑색 소포대를 형성하였다. 부화 후 90~93일째 평균 전장이 19.91${\pm}$1.63 mm(n=20)였고, 모든 지느러미 줄기 수가 정수에 달하였으며, 모든 반문이 형성되어 치어기로 이행하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 제3회 최신 분말제품 응용기술 Workshop
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• pp.25-37
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• 2002

The most important industrial application of gamma radiation in characterizing green compacts is the determination of the density. Examples are given where this method is applied in manufacturing technical components in powder metallurgy. The requirements imposed by modern quality management systems and operation by the workforce in industrial production are described. The accuracy of measurement achieved with this method is demonstrated and a comparison is given with other test methods to measure the density. The advantages and limitations of gamma ray densitometry are outlined. The gamma ray densitometer measures the attenuation of gamma radiation penetrating the test parts (Fig. 1). As the capability of compacts to absorb this type of radiation depends on their density, the attenuation of gamma radiation can serve as a measure of the density. The volume of the part being tested is defined by the size of the aperture screeniing out the radiation. It is a channel with the cross section of the aperture whose length is the height of the test part. The intensity of the radiation identified by the detector is the quantity used to determine the material density. Gamma ray densitometry can equally be performed on green compacts as well as on sintered components. Neither special preparation of test parts nor skilled personnel is required to perform the measurement; neither liquids nor other harmful substances are involved. When parts are exhibiting local density variations, which is normally the case in powder compaction, sectional densities can be determined in different parts of the sample without cutting it into pieces. The test is non-destructive, i.e. the parts can still be used after the measurement and do not have to be scrapped. The measurement is controlled by a special PC based software. All results are available for further processing by in-house quality documentation and supervision of measurements. Tool setting for multi-level components can be much improved by using this test method. When a densitometer is installed on the press shop floor, it can be operated by the tool setter himself. Then he can return to the press and immediately implement the corrections. Transfer of sample parts to the lab for density testing can be eliminated and results for the correction of tool settings are more readily available. This helps to reduce the time required for tool setting and clearly improves the productivity of powder presses. The range of materials where this method can be successfully applied covers almost the entire periodic system of the elements. It reaches from the light elements such as graphite via light metals (AI, Mg, Li, Ti) and their alloys, ceramics ($AI_20_3$, SiC, Si_3N_4, $Zr0_2$, ...), magnetic materials (hard and soft ferrites, AlNiCo, Nd-Fe-B, ...), metals including iron and alloy steels, Cu, Ni and Co based alloys to refractory and heavy metals (W, Mo, ...) as well as hardmetals. The gamma radiation required for the measurement is generated by radioactive sources which are produced by nuclear technology. These nuclear materials are safely encapsulated in stainless steel capsules so that no radioactive material can escape from the protective shielding container. The gamma ray densitometer is subject to the strict regulations for the use of radioactive materials. The radiation shield is so effective that there is no elevation of the natural radiation level outside the instrument. Personal dosimetry by the operating personnel is not required. Even in case of malfunction, loss of power and incorrect operation, the escape of gamma radiation from the instrument is positively prevented.