• 농업생명과학연구
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• 제43권6호
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• pp.77-84
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• 2009

Using recombinant DNA technology, the vector system containing minimal fragment of a bacterial hemoglobin gene (vgb) was constructed. When this vector was inserted into Escherichia coli, the growth of the host was significantly improved in both viable cell counts and absorbance measurement, compared to that of the wild type strain. In addition, by minimizing the size of bacterial hemoglobin in the vector, the ability of vgb in growth improvement was augmented, due to the reduction of metabolic burden from the maintenance and replication of the plasmid. By using this system, it is expected that the growth of microorganisms can be improved even in the hypoxic condition.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.366-369
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• 2002

Subsurface biobarrier technology has potential applications to contain contaminated groundwater and/or to degrade toxic pollutants in groundwater. Most biobarrier studies were conducted under aerobic condition, however there were several obstacles to make aerobic condition. Thus, In this study, we examined biobarrier formation under denitrifying condition by using nitrate as an electron acceptor. Experiments were performed with a sand column inoculated with activated sludge from the nearby WWTP. The substrate medium was pumped to the sand column in an upflow mode. During the low substrate loading rate period, the extent of reduction rate in hydraulic conductivity was found similar throughout the column, and permeability became relatively stable after couple of days. However, during the high substrate loading rate period, the column demonstrated a gradient of permeability reduction, with the greatest reduction in sections nearest the column inlet. Rapid growth of microorganisms near the column inlet resulted in the unbalanced reduction of hydraulic conductivity throughout the sand column. As a result, at this denitrifying condition the thickness of biobarrier could be controlled by adjusting the medium conditions of microbial growth.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.96.1-96
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• 2003

Serratia plymuthim A21-4 strongly inhibits the mycelial growth, zoospore formation, and cystospore germination of Phytophthor spp and Pythium species. The bacterial isolate produced antifungal substance and chitinase. The bacteria also enhanced to plant growth remarkably in low nutritional condition. The application of cell suspension of A21-4 to pepper seedlings in greenhouse experiments and soil drenching in farmer's field was proved successfully to control the phythophthora blight of pepper. For the effective control, however, relatively high density of cell number(10$\^$9/cfu/$m\ell$) is required. Density effect was similar in plant growth promoting activity of A21-4. Though this investigation we improved the problem with changes of culture condition of bacteria and some nutritional amendment.

• 대한수학회보
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• 제60권6호
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• pp.1673-1685
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• 2023

Inspired by Hongjie Dong and Qi S. Zhang's article [3], we find that the analyticity in time for a smooth solution of the heat equation with exponential quadratic growth in the space variable can be extended to any complete noncompact Riemannian manifolds with Bakry-Émery Ricci curvature bounded below and the potential function being of at most quadratic growth. Therefore, our result holds on all gradient Ricci solitons. As a corollary, we give a necessary and sufficient condition on the solvability of the backward heat equation in a class of functions with the similar growth condition. In addition, we also consider the solution in certain L^p spaces with p ∈ [2, +∞) and prove its analyticity with respect to time.

• 한국버섯학회지
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• 제3권1호
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• pp.40-44
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• 2005

노랑느타리버섯의 인공재배를 위한 우량균주 선발 및 균사배양적 특성을 조사한 결과는 다음과 같다. 1) 노랑느타리버섯균의 적정배지는 MCM에서 87.8mm/10일로 균사생장과 균사밀도가 가장 좋았으며, 그 다음은 PDA, YM, MEA, Czapek 순이었다. 2) 노랑느타리버섯의 균사생장과 밀도에 가장 적정한 온도는 $25^{\circ}C$이었으며 $5^{\circ}C$에서는 균사가 사멸하였다. KNAC2003 균주는 $25^{\circ}C$에서 87.8mm/10일로 균사생장과 밀도가 가장 양호하였으며, 온도별로는 25, 30, 20, 35, 10, $5^{\circ}C$ 순으로 균사생장 속도와 밀도가 좋았다. 3) 노랑느타리버섯의 균사생장과 밀도에 가장 적정한 산도(pH)는 6.0에서 88.3mm/10일이며 이보다 높거나 낮으면 균사생장과 밀도에 저해를 받는다.

• 환경생물
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• 제27권1호
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• pp.82-87
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• 2009

우리나라의 주요 우점종인 상수리나무, 굴참나무, 신갈나무의 생태적 특성을 밝히기 위하여 식물생장에서 가장 중요하다고 판단되는 광, 토양수분, 영양소를 이들 3종의 참나무 유식물에 각각 실내에서 처리하여 그 생육반응을 관찰하고, 분석하고자 시도하였다. 상수리나무와 굴참나무는 광이 높을수록 잘 자라는 경향이 있었고, 신갈나무만이 뚜렷한 경향이 없었다. 신갈나무는 낮은 광도에서도 생육이 크게 감소하지 않았다 굴참나무와 신갈나무는 수분구배에 따라 생육의 차이가 없었고, 상수리나무만이 약간 높은 구배에서 잘 자랐을 뿐이었다. 상수리나무, 굴참나무와 신갈나무 모두는 영양소가 적을 때 잘 자랐고, 높을수록 못 자랐다. 영양소 구배에 따른 감소정도는 굴참나무, 신갈나무, 상수리나무 순으로 낮았다. 이상으로 볼 때, 신갈나무는 피음조건에, 상수리나무는 토양이 다습한 조건에 그리고 굴 참나무는 유기물이 적은 조건에서 각각 적응한 종이라고 판단된다.

• 한국환경과학회지
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• 제28권1호
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• pp.147-158
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• 2019

In this study, we investigated the influences of abnormal high temperature on growth, yield and physiologically active substances of the strawberry. General strawberry cultivars in the $20^{\circ}C$ growth condition showed much better growth of leaf number, length, diameter along with plant height, compared with those in $22.5^{\circ}C$ or $25^{\circ}C$. But the cultivars of both 'Sulhyang' and 'Mehyang' showed good growth and development at $25^{\circ}C$ with the roots showing great growth at $20^{\circ}C$. The quality and yield of the strawberry were best in the $20^{\circ}C$ growth condition, but the merchantability deteriorated in the $25^{\circ}C$ high temperature condition. As for the content of the physiologically active substances of the strawberry, it increased at $20^{\circ}C$, the optimum growth temperature, but decreased at $25^{\circ}C$. The physiologically active substances in the strawberry differed among the cultivars, the contents of cyanidin-3-glucoside, cinchonine, ellagic acid and cinnamic acid higher in the 'Mehyang', whereas the content of fisetin is higher in the 'Sulhyang' cultivar.Consequentially, the high temperature in summer has a negative effect on the physiological active ingredients of the strawberry, which was increased in the strawberry cultivated at proper temperature, and high quality strawberry production was possible.

• 한국결정성장학회지
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• 제9권3호
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• pp.303-308
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• 1999

As a semiconductor material for electronic devices operated under extreme environmental conditions, silicon carbides(SiCs) have been intensively studied because of their excellent electrical, thermal and other physical properties. The growth characteristics of single-crystalline 4H-SiC homoepitaxial layers grown by a thermal chemical vapor deposition (CVD) were investigated. Especially, the successful growth condition of 4H-SiC homoepitaxial layers using a SiC-uncoated atmospheric pressure chamber and carried out using off-oriented substrates prepared by a modified Lely method. In order to investigate the crystallinity of grown epilayers, Nomarski optical microscopy, Raman spectroscopy, photoluninescence(PL), scanning electron microscopy(SEM) and other techniques were utilized. The best quality of 4H-SiC homoepitaxial layers was observed in conditions of growth temperature $1500^{\circ}C$ and C/Si flow ratio 2.0 of $C_{3}H_{8}\;0.2\;sccm\;&\;SiH_{4}\;0.3\;sccm$. The growth rate of epilayers was about $1.0\mu\textrm{m}/h$ in the above growth condition.

• 한국작물학회지
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• 제45권5호
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• pp.282-287
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• 2000

Soybean [Glycine max (L.) Merrill] crops, grown in a rice soybean rotation, can suffer when grown in soil with excessive moisture. The objective of this work were to determine the reduction in growth and yield, responses of vegetative and reproductive growth of soybean to excessive soil moisture achieved by prolonged irrigation. Responses of different cultivars were determined at growth stages from V6 to R8 to clarify the sensitive growth stages or characteristics to excessive soil moisture. Cultivar differences in response to excessive soil moisture condition were conspicuous in seed dry weight and harvest index (HI) but not in the response of seed number or pod number per plant. The timing of irrigation causing the condition of excessive soil moisture influenced the vegetative or reproductive traits. Soybean plants were more affected by irrigation commencing at the pre-flowering than at the post-flowering stage. Post-flowering irrigation did not reduce growth of vegetative organs significantly; in fact the growth of stems and leaves was facilitated by the prolonged irrigation commencing at flowering. Differences between cultivar response to prolonged irrigation were assumed to relate to the reduced amount of assimilates translocated to the reproductive organ.

• 한국잡초학회지
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• 제14권1호
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• pp.62-70
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• 1994

각(各) 재배양식별(栽培樣式別)로 벼와 피의 생육특성(生育特性) 및 각부형태적(各部形態的) 진전(進展)의 변화(變化)를 알아보기 위하여 파종(播種) 및 이앙후(移秧後)(DAS/T) 1, 2, 3, 5, 7, 10, 15, 20일째에 식물체(植物體)를 굴취(堀取)하여 조사(調査)하였으며, 조사내용별(調査內容別) 결과(結果)는 다음과 같다. 1) 벼와 피의 발아(發芽) 및 입묘양상(立苗樣相)의 차이(差異) 가. 벼는 발아시(發芽時) 초엽과 유근 모두 같은 배반(胚盤)에서 출현(出現)하는데 반해 피는 그와 반대방향(反對方向)에서 출현(出現)하였다. 나. 재배양식(栽培樣式)간의 벼 입묘양상(立苗樣相)은 건답직파(乾沓直播)의 경우 지상부(地上部) 및 지하부생육(地下部生育)이 균형적(均衡的)이었으나 담수직파(湛水直派)는 지하부(地下部) 위주(爲主)의 생육(生育)이 이루어졌고 표면(表面)벼보다 토중(土中)벼의 입묘(立苗가) 더 좋았다. 2) 벼와 피의 생육특성(生育特性) 차이(差異) 가. 초기생육(初期生育)을 통한 벼와 피간의 초장차이(草長差異)는 담수직파(湛水直播)보다는 건답직파(乾沓直播)에서 더 컸고 같은 직파(直播)에서도 피가 표면(表面)벼나 토중(土中)벼보다 컸으며 이앙재배(移秧栽培)에서는 벼가 피보다 지속적으로 우위성을 유지하였다. 나. 근장(根長)은 모든 재배양식(載培樣式)에서 피가 벼보다 컸으며 벼와 피간의 근장(根長) 차이(差異)는 담수(湛水)보다 건답(乾沓)에서, 이앙(移秧)보다 직파(直播)벼에서 유의적(有意的)으로 컸다. 다. 地上部重(지상부중)은 직파(直播)의 경우 건답(乾沓짧)피가 가장 컸으며 벼와 피간(間)의 지상부(地上部) 생육중(生體重) 차이(差異)는 담수(湛水) 보다 건답(乾沓에)에서, 표면(表面)벼보다는 토중(土中)벼가, 그리고 벼보다 피가 컸으나 이앙조건(移秧條件)에서는 이앙(移秧)벼가 피보다 우위에 있었다. 라. 지상부(地下部) 생체중(生體重)은 직파(直播)의 여러 양식간(樣式間)에 차이(差異)를 보이지 않았으나 파종후(播種後) 10일(日) 이후부터 피가 벼를 능가하는 경향이었고 이앙재배(移秧栽培)에서는 벼가 피보다 지속적으로 우위에 있었다. 마. 중경장(中莖長)은 피만이 형성되었고 건답(乾沓)보다는 담수(湛水)에서, 파종(播種)깊이가 클수록 더 컸다. 바. 엽령(葉齡)은 직파재배(直播載培)에서 피가 벼보다 크고, 벼와 피간의 엽령(葉齡) 차이(差異)는 담수(湛水)보다는 건답(乾沓)에서 약간 더 컸으며 이앙재배(移秧我培)에서는 벼가 피보다 컸다. 사. 엽면적지수(葉面積指數)는 벼와 피간의 차이(差異)가 담수직파(湛水直播)보다는 건답직파(乾沓直播)에서 월등히 컸으며 이앙조건(移秧條件)에서 벼가 유의적으로 컸다. 아. 엽록소함량(葉綠素含量)은 각 재배양식(我培樣式)에서 피가 유의적으로 높았으며 담수직파(湛水直播)보다는 이앙(移秧)벼에서, 이앙(移秧)벼보다는 간답직파(乾畓直播)에서 높았다.