Tantalum nitrides () have been developed to substitute the Cd based pigments for non-toxic red pigment. Various doping elements were doped to reduce the amount of high price Tantalum element used and preserve the red color tonality. Doping elements were added in the synthesizing process of precursor of amorphous tantalum oxides and then Tantalum nitrides doped with various elements were obtained by ammonolysis process. The average particle size of final nitrides with secondary phases was larger than the nitride without the secondary phases. Also secondary phases reduced the red color tonality of final products. On the other hand, final nitrides without secondary phase had orthorhombic crystal system and presented good red color. In other words, in the case of nitrides without secondary phases, doping elements made a solid solution of tantalum nitride. In this context, doping process controlled the ionic state of nitrides and the amount of oxygen/nitrogen in final nitrides affected the color tonality.
주요 엽채류 7종의 주년 안정생산을 위한 담액수경 재배 시 양액의 순환주기가 양액의 용존산소 농도, 엽채류의 생육, 그리고 식물영양소의 함량에 미치는 효과를 검토한 결과, 양액을 1일 10분 순환 처리구는 정식 13일 후 용존산소 농도가 급격하게 떨어지고 17일 후에는 2.8mg L-1, 20일 후에는 최저 1.5mg L-1까지 낮아졌다. 처리 20일 후 7가지 엽채류의 생체중은 1일 10분 처리구에서는 대조구인 10분 순환/110분 정지 처리구에 비해 0~24% 범위에서 낮아졌으며, 10분 순환/10분 정지 처리구에서는 -2~34% 증가하였다. 양액의 순환주기가 짧을수록 식물체 엽내 P의 함량이 증가하였으며, 식물체의 C/N율과 비타민 C 함량은 감소하였다. 이상의 결과, 담액수경 엽채류의 안정적인 생육과 식물영영소의 흡수를 위해서 2시간에 10분 정도의 양액 순환 처리가 효율적이었다.
The film coated snap bean (Phaseolus vulgaris) seeds with five different coating materials treated with 3% increase in seed weight were planted at sandy loam soil controlled moisture content of 18, 19, 20 and 21 %. The oxygen diffusion rate (ODR) was calculated from the different moisture content soil. The number of normal seedlings, seedling vigor, and seedling capability in field (seed vigor x dry matter weight) were observed at 9 days after planting and compared to the changes of ODR. The germination rate and ODR were sharply decreased simultaneously in the seeds planted at 21 % soil moisture content. Seedling emergence did not occur at all as the soil moisture content increased above 22 %. Hence this value should be considered as the threshold of soil moisture content for seedling emergence. An ODR value under 20% did not influence the percent emergence significantly. The certain difference observing in the emergence at the same ODR was not related clearly to the condition of soil. So it can be assumed that the limit of soil moisture content for the emergence of snap bean was approximately 20%. The value of 18% soil moisture content may be considered as the optimum for snap bean emergence. There was close relationship between the mean value of ODR in different soil moisture contents and the emergence. The germination rates of the seeds coated with the different materials were quite different when the seeds were planted at 21 % soil moisture. Dry weight of the seedlings from film coated seeds was decreased slightly, but the germination rates were not much different from the non-treated control under relatively higher soil moisture content (21 %). Major factor lowering emergence rate was oxygen stress while film coating act as a minor constraint for snap bean sown in excess soil moisture condition.