• 센서학회지
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• 제22권4호
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• pp.244-248
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• 2013

The discovery of a two-dimensional electron gas (2DEG) in $LaAlO_3$ (LAO)/$SrTiO_3$ (STO) heterostructure has stimulated intense research activity. We suggest a new structure model based on $KNbO_3$ (KNO) material. The KNO thin films were grown on $TiO_2$-terminated STO substrates as a p-type structure ($NbO_2/KO/TiO_2$) to form a two-dimensional hole gas (2DHG). The STO thin films were grown on KNO/$TiO_2$-terminated STO substrates as an n-type structure to form a 2DEG. Oxygen pressure during the deposition of the KNO and STO thin films was changed so as to determine the effect of oxygen vacancies on 2DEGs. Our results showed conducting behavior in the n-type structure and insulating properties in the p-type structure. When both the KNO and STO thin films were deposited on a $TiO_2$-terminated STO substrate at a low oxygen pressure, the conductivity was found to be higher than that at higher oxygen pressures. Furthermore, the heterostructure formed at various oxygen pressures resulted in structures with different current values. An STO/KNO heterostructure was also grown on the STO substrate, without using the buffered oxide etchant (BOE) treatment, so as to confirm the effects of the polar catastrophe mechanism. An STO/KNO heterostructure grown on an STO substrate without BOE treatment did not exhibit conductivity. Therefore, we expect that the mechanics of 2DEGs in the STO/KNO heterostructures are governed by the oxygen vacancy mechanism and the polar catastrophe mechanism.

• 한국작물학회지
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• 제62권4호
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• pp.373-381
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• 2017

The main objective of this study was to increase the germination percentage of kenaf seeds with less number of times under non-saline and saline conditions. Therefore, the first goal was to assess the response of kenaf seeds to NaCl. The second goal was to evaluate the effects of $KNO_3$ on kenaf seed germination. The germination percentage exhibited a decreasing tendency in germination rate. Plant dry weight was approximately 0.2 g in all treatments at 5 days after germination. As time passed, the electrical conductivity (EC) value of hydro-priming (HP) consistently increased by 8.7 mS/cm at 24 hours of immersion. However, seeds primed with $KNO_3$ showed no difference in EC values even as times passed. Regarding the priming effect, priming in 100 mM $KNO_3$ concentration for 12 hours increased germination up to 85% in $H_20$ solution and in 0 mM $KNO_3$ concentration upto 73.8% under 0.3% NaCl solution, compared to that of Control. Germination synchronization, shoot length, and leaf unfolding of primed seeds were greater than those of the Control. In addition, main root and hair roots appeared more rapidly in the treated seeds and were more abundant compared to that of the Control. The T50 (times to reach 50% of the final germination percentage) of the Control in both $H_20$ and 0.3% NaCl solutions was 18 and 22 hours, respectively. However, when treated $KNO_3$ priming (0 to 100 mM) in $H_20$ and 0.3% NaCl solution, 9 hours was sufficient to reach T50. Primed (hydro-priming and $KNO_3$) seeds had a lower MDG (mean days untill germination; 0.6-0.62) compared to that of the Control (1.13-1.31) in $H_20$ and 0.3% NaCl solutions. Regarding dry weight of plants after priming, an increasing tendency after the priming treatment in the H20 solution was observed. Furthermore, no significant difference in plant dry weight under 0.3% NaCl stress was observed between the Control and primed seeds. Taken together, the results suggest that 50-100 mM $KNO_3$ priming for 24 hours optimize seed germination rate in less number of times of exposure with great vigor. Therefore, it is recommended for kenaf seed invigoration before planting.

• 한국약용작물학회지
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• 제24권3호
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• pp.177-182
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• 2016

Background: Many Taraxacum spp. plants are widely used in medicine, but some of them have propagation problems, such as strong dormancy and poor germination rates. This study investigated the effects of temperature, gibberellic acid ($GA_3$), and potassium nitrate ($KNO_3$) on seed germination in Taraxacum ohwianum. Methods and Results: The seeds (NIBRGR0000135524) were exalbuminous, and their length and width were $4.54{\pm}0.032mm$ and $0.97{\pm}0.029mm$, respectively. Various germination temperatures were tested (15, 20, 25, and $30^{\circ}C$), the optimum temperature for germination was found to be $20^{\circ}C$ (31.3%). High temperature ($30^{\circ}C$) resulted in non-typical seedlings (thickened and crumpled cotyledons, with a restricted root system). To increase the germination capacity, $GA_3$ (200, 500, and $1,000mg/{\ell}$) or $KNO_3$ (20, 50, 100, 200, and $500mg/{\ell}$) solutions were used as pre-soaking solutions instead of water. The $GA_3$ treatments increased the germination percentage and rate, but germination percentage was higher with the $KNO_3$ treatments. Under the $50-200mg/{\ell}\;KNO_3$ treatments, the germination percentage exceeded 80% after 12 days, and $50mg/{\ell}\;KNO_3$ was notably effective (91.2% after 15 days). Conclusions: T. ohwianum seeds showed improved germination at low temperatures. The best method for germination was presoaking in $50mg/{\ell}\;KNO_3$ for 24 h, in the dark at $4^{\circ}C$, and then incubating the germinated seed at $20^{\circ}C$ for 15 days.

• 한국환경농학회지
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• 제19권4호
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• pp.319-323
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• 2000

광산인근 논토양의 형태별 중금속 함량[수용태$(H_2O)$, 치환태 $(0.5M\;KNO_3)$, 유기복합태(0.5M NaOH), 탄산염태$(0.05M\;Na_2-EDTA)$, 황화잔류태$(4M\;HNO_3)$] 과 현미에 흡수 이행된 중금속과의 관계를 구명하기 위하여 5개 광산지역에서 30개 지점 논토양 및 현미를 대상으로 분석 검토한 결과는 다음과 같다. 광산인근 논토양의 Cd, Pb 및 Zn의 주된 형태는 EDTA 및 $HNO_3$ 침출태, Cu는 NaOH 및 $HNO_3$침출태였고, 식물에 흡수이행이 용이한 것으로 알려진 $H_2O\;+KNO_3$침출태의 함량비율은 Cd 25.1, Zn 8.7, Cu 4.0, Pb 0.4% 순으로 나타났다. 토양 pH와 $H_2O+KNO_3$침출태 중금속 함량비율은 고도의 부의 상관, $EDTA+HNO_3$침출태 중금속과는 고도의 정의 상관을 보였다. 토양의 총 중금속함량 수준에 따라 형태별 중금속함량의 분포비율은 다르게 나타났고, 특히 높은 함량수준에서 $H_2O+KNO_3$침출태 Cd, Cu, Pb 및 Zn의 분포비율이 높게 나타났다. 토양의 $H_2O+KNO_3$침출태 Cd, Cu, Pb 및 Zn함량비율은 토양 pH가 높은 지역(D site)에서 각각 1.06, 0.15, 0.008, 0.05%로 나타나 pH가 낮은 지역의 평균치 30.31, 4.06, 1.75, 10.16%보다 매우 낮게 나타났다. 현미중 Cd 및 Zn흡수이행과 관련이 큰 토양의 존재형태는 각각 $KNO_3$침출태, EDTA 및 $HNO_3$침출태로 나타났다.

• 한국토양비료학회지
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• 제25권1호
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• pp.57-61
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• 1992

질소염(窒素鹽)들의($(NH_4)_2SO_4$, $NH_4NO_3$, $KNO_3$, $Mg(NO_3)_2$, $Ca(NO_3)_2$, $(NH_2)_2CO$) 농도별(濃度別) 염강도(鹽强度)를 비교하고 영양액연속유출경사사경재배장치(營養液連續流出傾斜砂耕栽培裝置)를 이용하여 배추와 상치에 대한 발아장해정도(發芽障害程度)를 조사하였다. 그람분자량으로 동일농도(同一濃度)의 EC(electrical conductivity, mS/cm)를 측정한 결과 황산암몬은 1가염(價鹽)의 2배수준(倍水準)을 나타냈으나 질산고토, 질산석회는 1.5배정도 이었고 요소(尿素)는 전연 측정되지 않았다. 그리고 동일백분률(同一百分率) 농도(濃度)에서는 황산암몬(1.37)>질산암몬(1.22)>질산칼리(1.0)>질산석회(0.72)>질산고토(0.64)의 순(順)으로 EC치의 비율을 보였다. 배추와 상치의 발아에 가장 심한 장해를 주는 염(鹽)은 질산고토, 황산암몬이었으며 질산암몬도 질산칼리에 비하여 장해정도가 컸고 요소(尿素)는 질산칼리, 질산석회와 같이 가장 낮은 영향을 주었으나 농도가 짙어지면서 질산칼리, 질산석회도 장해를 나타냈다. 그리고 상치가 배추보다 발아장해에 더 예민한 편이었다. 발아장해(發芽障害)는 염농도(鹽濃度)보다 질소염(窒素鹽)의 종류(種類)에 더 큰 영향을 받는 것으로 나타났다.

• Restorative Dentistry and Endodontics
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• 제20권2호
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• pp.508-526
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• 1995

This experiment was performed to study mechanisms of desensitization by chemical desensitizing agents in hypersensitive dentin and compare effects of these agents by measuring the activity of intradental nerves and observing their occluding aspects on dentinal tubules with SEM over time after application of chemical desensitizing agents to the exposed dentinal surfaces. Canines of adult cats weighing 2-3 kg were cross-sectioned at 1.5 mm from incisal apex, and the smear layer of the exposed dentinal susface was removed by 32 % $H_3PO_4$ for 15 sec. Chemical desensitizing agents such as 10% $SrCl_2$, 5% $KNO_3$ and 30% $K_2C_2O_4$, were applied to the exposed dentin surfaces for 2 minutes. Intradental nerve activity was measured immediately after application of the agents, at 15 minutes and at 30 minutes by stimulating with 4M NaCl. To compare occluding ability of desensitizing agents on dentinal tubules in vivo and in vitro, the structures of the exposed dentinal surfaces of nonvital and vital teeth were morphologically observed by SEM. The results obtained were as follows : 1. Intradental nerve activity was decreased immediately after the application of 10 % $SrCl_2$, 5% $KNO_3$ and 30% $K_2C_2O_4$. (p<0.01), among which 30% $K_2C_2O_4$. showed the highest desensitizing effect(p<0.01). 2. The immediately decreased intradental nerve activity after application of 10 % $SrCl_2$ and 5% $KNO_3$ was increased over time. 10% $SrCl_2$ and 5% $KNO_3$ showed no desensitizing effect respectively at 30 minutes and at 15 minutes after application. 3. The immediately decreased intradental nerve activity after application of 30 % $K_2C_2O_4$ was persistently continued during the period of observation (p<0.01). 4. Precipitates of $SrCl_2$ and $KNO_3$ were not noted on the exposed dentinal surfaces and within dentinal tubules by SEM examination. On the other hand, 30 % $K_2C_2O_4$ produced precipitates on the exposed dentinal surfaces and openings of dentinal tubules without any formed preciptates within dentinal tubules. 5. Ten percent $SrCl_2$, 5 % $KNO_3$ and 30 % $K_2C_2O_4$ showed no differences in their occluding aspects on dentinal tubules either in vivo or in vitro studies and either immediately following application or at 30 minutes. These results suggest that the desensitizing effect of $SrCl_2$ and $KNO_3$ is resulted from their reducing effect on the intradental nerve activity rather than from their precipitates' occluding the dentinal tubules. However, desensitizing effect of 30 % $K_2C_2O_4$, is probably resulted from its precipitates' occluding the openings of the dentinal tubules as well as from it's reducing effect on the intradental nerve actibity.

• Transactions on Electrical and Electronic Materials
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• 제15권2호
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• pp.60-65
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• 2014

This article explains the experimental results of ferroelectric polarization switching (FPS) of potassium nitrate ($KNO_3$) with different polymers such as polyvinylidene fluoride (PVDF) and polyvinyl fluoride (PVF) using simple melt-press techniques. To analyze the ferroelectric polarization switching in potassium nitrate ($KNO_3$) composite films at room temperature, we applied the Ishibashi and Takagi theory (based on Avrami model) to the switching current transient. To investigate the dimensionality of domain growth, the ferroelectric polarization switching current (FPS current) was observed from the square - wave bipolar signals across a resistance of $0.1k{\Omega}$ in series with the composite films. The existence of a switching current transient pulse confirmed the ferroelectricity and indicated the stability of the ferroelectric phase (phase III) of $KNO_3$ at room temperature. Polarization hysteresis (P-E) characteristics supported the prominent features of ferroelectric polarization switching in the composite films at room temperature.

• 자원리싸이클링
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• 제10권4호
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• pp.3-9
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• 2001

박판상을 갖는 세리사이트 분말의 분쇄 효율을 향상시키기 위하여 분쇄조제 1 M $KNO_3$ 용액이 첨가된 분말을 시간에 따라 분쇄하였으며, 증류수만을 첨가하여 분쇄한 분말과 비교하였다. 분쇄된 분말의 평균 입자크기는 분쇄시간 1시간까지는 감소하다가 1시간 이후에는 미세 입자들간의 응집으로 증가하였다. 세리사이트 분말에 $1 M KNO_3$용액을 첨가한 경우 1시간 분쇄하였을 때 평균입자크기가 $1.9mu$m로 가장 작게 나타났으며 증류수를 첨가한 경우에도 1시간 분쇄 시 $2.4\mu$m로 가장 작게 나타났다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.49-49
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• 2007

최근 반도체 소자의 고집적화와 나노 (nano) 크기의 회로 선폭으로 인해 기존에 사용되었던 텅스텐이나 알루미늄 금속배선보다, 낮은 전기저항과 높은 electro-migration resistance가 필요한 Cu 금속배선이 주목받게 되었다. 하지만, Cu CMP 공정 시 높은 압력으로 인하여 low-k 유전체막의 손상과 디싱과 에로젼 현상으로 인한 문제점이 발생하게 되었다. 본 논문에서는, $KNO_3$ 전해액의 농도가 Cu 표면에 미치는 영향을 알아보기 위해 Tafel Curve와 CV (cyclic voltammograms)법을 사용하여 전기화학적 특징을 알아보았고 scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray Diffraction (XRD) 분석을 통해 금속표면을 비교 분석하였다.

• 원예과학기술지
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• 제17권2호
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• pp.136-137
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• 1999

신나팔나리의 발아률(發芽率) 및 상품성 향상을 위하여 $GA_3$, 염류(鹽類) 및 저온(低溫) 등을 이용하여 종자 priming 처리한 결과 파종 후 10일째 초기 발아률(發芽率)은 $Ca(NO_3)_2$ 200mM 및 $KNO_3$ 200mM 처리구가 높았으나 최종 발아률(發芽率)에서는 처리구간에 유의차가 없었으며 발아세는 $Ca(NO_3)_2$ 200mM 처리구에서 가장 높게 나타났다. 초기 생육은 $Ca(NO_3)_2$ 200mM, $KNO_3$ 200mM 처리구가 엽수(葉數)가 많았고 구경(球徑)이 컸으며 건물중(乾物重)도 무거웠다.