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The Survey on Pesticide Residues in Vegetables Collected In Seoul (서울지역 유통 채소류의 잔류농약 조사)

  • Jang, Mi-Ra;Moon, Hyun-Kyung;Kim, Tae-Rang;Yuk, Dong-Hyun;Kim, Eun-Hee;Hong, Chae-Kyu;Choi, Chae-Man;Hwang, In-Sook;Kim, Jung-Hun;Kim, Moo-Sang
    • The Korean Journal of Pesticide Science
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    • v.15 no.2
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    • pp.114-124
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    • 2011
  • The characteristics of pesticide residues by multiresidue analysis method using GC, HPLC and GC-MSD were examined for 18,069 numbers of 91 kinds of vegetables in Seoul from 2007 to 2009. Detection rates of pesticide residues were 11.2% in 2007, 8.5% in 2008 and 12.0% in 2009, respectively, and the excess rates of Maximum Residue Limits (MRLs) showed a declining tendency as 4.6% in 2007, 2.8% in 2008 and 2.1% in 2009, respectively. The pesticides exceeding MRLs were 43 ingredients in 2007, 30 ingredients in 2008 and 36 ingredients in 2009, respectively. The frequencies of pesticides exceeding MRLs were 71 of azoxystrobin in 2007, 29 of procymidone in 2008, 24 of endosulfan in 2009, respectively. The excess rate of mustard green for MRLs in comparison with sample numbers was the highest among vegetables analyzed more than 10 cases each year. As a result of comparing annually pesticide residues about pesticide ingredients showed high frequency rates for pesticide detection, there was a statistical significance for the detection quantities of diazinon, endosulfan, paclobutrazol and procymidone.

Effects of 2-Mercaptoethanol on the Protoplast Formation and Osmotic Stabilizers on the Protoplast Reversion of Pyricularia oryzae Cavara (벼 도열병균(稻熱病菌)의 원형질체(原形質體) 생성(生成)에 미치는 2-Mercaptoethanol과 복귀(復歸)에 미치는 삼투압 안정제(安定劑)의 영향(影響))

  • Kim, Heung-Tae;Chung, Hoo-Sup
    • The Korean Journal of Mycology
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    • v.17 no.1
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    • pp.1-6
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    • 1989
  • The mycelia of Pyricularia oryzae were treated with enzyme solution mixture consisting of Driselase, ${\beta}-Glucuronidase$, Cellulase, and Macerozyme R-10 for the production of protoplasts. More protoplasts were formed from mycelia of race KJ 101 of P. oryzae than that of race KI 315a in the enzyme mixtures. The number of protoplasts was decreased in the untreated control three hrs after the enzyme treatment, whereas the number was increased in the treatments with 10, 50 and 100 mM 2-mercaptoethanol, respectively. The number of protoplasts increased to reach maximum at five hrs after treatment of 10 mM 2-mercaptoethanol, but the least was found in 200 mM. The protoplasts of P. oryzae in a liquid medium containing 2.5% yeast extract, and 2% dextrose reverted to the mycelia after five hrs shaking incubation at $27^{\circ}C$. Some protoplasts produced yeast like buds and the buds were developed to irregularly shaped chains of cell protruded a germ tube like hypha from the distal cell. Once in a while a germ tube like hypha protruded directly from the protoplasts. Except in the first type of reversion, other protoplasts reverted to the normal mycelia. The reversion frequency was highest on PDA with stabilizer of 0.6 M KCl. No reversion of protoplasts occurred on water agar regaardless oftreaatments.

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A Study on the Carbothermic Reduction and Refining of V, Ta and B Oxides by Ar/Ar-H2 Plasma (Ar/Ar-H2 플라즈마에 의한 V, Ta, B 산화물의 탄소용융환원 및 정련)

  • Chung, Yong-Sug;Park, Byung-Sam;Hong, Jin-Seok;Bae, Jung-Chan;Kim, Moon-Chul;Baik, Hong-Koo
    • Transactions of the Korean hydrogen and new energy society
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    • v.7 no.1
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    • pp.81-92
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    • 1996
  • The Ar/Ar-$H_2$ plasma method was applied to reduce oxides and refine metals of V, Ta and B. In addition, the high temperature chemical reaction in Ar plasma and of the refining reaction in the Ar-(20%)$H_2$ plasma were analyzed. The crude V of 96wt% purity was obtained at the ratio of $C/V_{2}O_{5}=4.50$ by the Ar plasma reduction grade and the maximum reduction was obtained at $C/V_{2}O_{5}=4.50$ due to the $O_{2}$ loss from the thermal decomposition of vanadium oxide. In the Ar-(20%)$H_2$ plasma refining, the metallic V of 99.2wt% was produced at the ratio of $C/V_{2}O_{5}=4.40$. It was considered that a main refining reaction resulted from the chemical reaction between the residual carbon and residual oxygen. The metallic Ta of 99.8wt% was obtained at the ratio of $C/Ta_{2}O_{5}=5.10$ in a Ar plasma reduction and the Oz loss from the thermal decomposition of tantalum pentoxide did not take place. The deoxidation reaction was more significant than the decarburization reaction in the Ar-(20%)$H_2$ plasma refining and the metallic Ta of 99.9wt% was produced within the range of $C/Ta_{2}O_{5}$ ratio of 4.50 to 5.10. The Vickers hardness of Ta in the above mentioned range was about 220Hv due to the decrease in a residual oxygen by the deoxidation reaction. On the other hand, C is no suitable agent for the reduction of $B_{2}O_{3}$ by the Ar and Ar-$H_2$ plasma. But Fe-B-Si alloy was produced with the reduction of $B_{2}O_{3}$ in the melt when Fe, C, $B_{2}O_{3}$, and ferroboron mixtures were melted by the high frequency induction melting.

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Analysis of the Characteristics of Precipitation Over South Korea in Terms of the Associated Synoptic Patterns: A 30 Years Climatology (1973~2002) (종관적 특징에 따른 남한 강수 특성 분석: 30년 (1973~2002) 기후 통계)

  • Rha Deuk-Kyun;Kwak Chong-Heum;Suh Myoung-Seok;Hong Yoon
    • Journal of the Korean earth science society
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    • v.26 no.7
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    • pp.732-743
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    • 2005
  • The characteristics of precipitation over South Korea from 1973 to 2002 were investigated. The synoptic patterns inducing precipitation are classified by 10 categories, according to the associated surface map analysis. The annual mean frequency of the total precipitation, its duration time and amount for 30 years are 179 times, 2.9 hours, and 7.1 mm, respectively. About $59\%$ of the total precipitation events were associated with a synoptic low. The dominant patterns are identified with respect to seasons: A synoptic mobile low pressure pattern is frequent in spring, fall, and winter, whereas low pressure embedded within the Changma and orography induced precipitation are dominant in summer and in winter. For the amount of precipitation, precipitation originated from tropical air associated with typhoon, tropical convergence, and Changma is more significant than that with other pressure patterns. The statistical elapse time reaching to 80 mm, which is the threshold amount of heavy rainfall watch at KMA, takes 12.9 hours after the onset of precipitation. The probability distribution function of the precipitation shows that the maximum probability for heavy rainfall is located at the south-coastal region of the Korean peninsula. It is also shown that the geographical distribution of the Korean peninsula plays an important role in occurrence of heavy rainfall. For example, heavy precipitation is frequently occurred at Youngdong area, when typhoon passes along the coastal region of the back borne mountains in the peninsula. The climatological classification of synoptic patterns associated with heavy rainfall over South Korea can be used to provide a guidance to operational forecast of heavy rainfall in KMA.

Relationship of Maternal Perception of the Infant Temperament and Confidence and Satisfaction of Maternal Role (어머니가 지각한 영아기질과 어머니 역할수행에 대한 자신감 및 만족도의 관계)

  • Lee Young-Eun;Kang Yang-Hee;Park Hae-Sun;Hwang Eun-Ju;Mun Mi-Young
    • Child Health Nursing Research
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    • v.9 no.2
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    • pp.206-220
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    • 2003
  • Purpose: this study was intended to search the relationship between perception of the infant temperament in mother of infant at the age of 1~12 months and maternal confidence and satisfaction in performing maternal role, and to submit a basic data to establish a nursing intervention program which is helpful for determination of infant development and performing maternal role promotion by identify variables associated with infant temperament. Method: The subjects of this study were 300 mothers of infant at the age of 1~12 months who visited well baby clinic in 4 hospitals in Busan city and Kyoung-Nam province. Final analysis was performed in 293 cases. Seven cases was excluded in this study because of its inappropriate data collection. The data was collected from 1st July to 15th August 2002. The questionaries which were fill-up by mother were collected. Infant temperament was measured by using the tool of 'what my baby is like'(WBL) which was developed by Priham et. al.(1994) and translated by Bang(1999). The scale of postpartum self evaluation which was developed by Lederman et al(1981) and translated by Lee(1992) was used for the confidence and satisfaction of maternal role. All statistical analyses were performed using SPSS-PC for window, version 10.0: frequency, percentage, minimum, maximum, mean, SD, t-test, ANOVA, Post-hoc test(Scheffe's test), Pearson Correlation Coefficients. Result: The mean score of maternal perception of the infant temperament was 6.17±1.04, and mother recognized her infant as positive. The mean score of confidence of maternal role was 2.89± .41 and this revealed in an average level. The mean score of satisfaction of maternal role was 3.29± .51 and this revealed in a higher level. There was a weak significant positive correlation between the score of maternal perception of infant temperament and confidence of maternal role(r=0.176, P= .003), but there was no significant correlation between satisfaction of maternal role(P> .05). It revealed the more maternal perception of the infant temperament as positive, the higher confidence of maternal role. There was a moderate significant positive correlation between confidence of maternal role and satisfaction of maternal role(r=0.410, P= .000). It revealed the more confidence of maternal role, the higher satisfaction of maternal role. The variables related with the score of maternal perception of infant temperament were the type of delivery (t=-2.600, P= .010), experience of learning baby care(t=2.382, P= .018), maternal perception on baby's health status(F=3.467, P= .033), maternal perception on her health status(F=3.467, P= .027), baby's age(F=3.080, P= .028). Conclusion: Our result showed the confidence of maternal role was increased as the maternal perception of infant temperament was positive, and conformed that the confidence of maternal role was also related with satisfaction of maternal role. Prenatal education, type of delivery, baby's age were also related with the maternal perception of infant temperament. So, nursing intervention program of developmental stage maybe necessary in order to help maternal perception of infant temperament as positive, and it will be increased the confidence of maternal role and satisfaction of performing maternal role which was considered as real indicate of achievement of maternal role.

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Effect of the magnetism(neodymium magnet) on growth factor receptors of osteoblasts (희토류 자석의 자성이 골모세포 성장인자 수용체의 증가에 미치는 영향에 관한 연구)

  • Lee, Sang-Min;Lee, Sung-Bok;Choi, Boo-Byung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.19 no.2
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    • pp.87-96
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    • 2003
  • The purposes of this study were to find out the optimum intensity of magnetic field where magnetism could promote the activity of osteoblast, and to discover the possibility of clinical application in the areas of dental implants and bone grafts by confirming the effect of clinically increasing bone formation. In this experiment, we used the Neodymium magnet, which had magnetic power six times as strong as the current ones and enabled the resistances against the demagnetization up to 20 to 50 times to be minimized with the size of 1mm in sight. In order to culture cells, a specially designed device was used. It was made to adjust the distance and accordingly to control the intensity of the magnetic field, by placing the cell culture plate in the center with a magnet of 1mm long and thick installed on the both ends. Using MC3T3-E1 cell, a kind of osteoblast-like cell, we cultured, for 24 hours, not only the test group which had been cultured under the magnetic fields with different intensity of 5, 10, 50, 100, 500, and 1000 Gauss, but also the control group excluding the influences of the magnetic field. After observing the cell's form and the density of the culture medium through an inverted microscope, we made a series of proceedings needed for the immunofluoroscence staining, such as fixation, normal serum reaction, primary antibody reaction, and secondary antibody reaction. And with a fluorescence microscope, we observed those-above and compared the frequency of expression of IFG-1 receptor. To make a Western immunoblotting analysis, the cells cultured under the same condition as the above had the procedure of the lysis buffer and the acrylamide gel electrophoresis was carried out. Protein transferred into the nitrocellulose membrane and tested on the primary and the secondary antibody reactions was observed and compared. The results were as follows: When observed through an inverted microscope, the nuclear divisions of the cells under the magnetic field of 10 Gauss were the most active, and the density of the cells could be observed the most enormously. As the result of an immunofluoroscence staining of IGF-1 receptor, the expression of IFG-1 was the most frequently observed under the magnetic field of 10 Gauss. On the other hand, few differences of consideration were made between the test group cultured under the magnetic fields of 5, 500, and 1000 Gauss and the control group. In respect of the expression of IFG-1 receptor, the test group cultured under the magnetic fields of 50 and 100 Gauss were higher than the control group, and lower than that cultured under the magnetic field of 10 Gauss.(p<0.05) According to the Western immunoblotting analysis, the band of IFG-1 receptor which had 85KDa of molecular weight was the darkest. Judging from the above-mentioned results, the growth factor receptor of an osteoblast cell which was an important criterion for the bone formation was increased in maximum under the magnetic field of 10 Gauss. Moreover it was observed that the optimum intensity of magnetic field in which magnetism made the activity of the osteoblast cell increase was about 10 Gauss.

Comparative Study on Acoustic Characteristics of Vocal Fold Paralysis and Benign Mucosal Disorders of Vocal Fold (성대마비와 양성 성대점막질환의 음향학적 특성비교)

  • Kong, Il-Seung;Cho, Young-Ju;Lee, Myung-Hee;Kim, Jong-Seung;Yang, Yun-Su;Hong, Ki-Hwan
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.18 no.2
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    • pp.122-128
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    • 2007
  • This study aims to analyze the voices of the patients with voice disorders including vocal fold paralysis, vocal fold cyst and vocal nodule/polyp in the aspect of acoustic phonetics. This study intends to collect subsidiary acoustic data in order to make a speech treatment and an standardization of vocal disorders. Subjects and Methods: The subjects of this study were 64 adult patients who underwent indirect laryngoscopy and laryngostroboscopy, and were diagnosed as vocal fold paralysis, vocal fold cyst or vocal nodule/polyp. Experimental group consisted of 20 patients who were diagnosed as vocal fold paralysis, 21 patients who were diagnosed as vocal fold cyst and had the average age of 42.0 $({\pm}10.03)$ ; and 23 patients who were diagnosed as vocal nodule/polyp and had the average age of 40.9 $({\pm}13.75)$. For the methodology of this study, the patients listed above were asked to sit in a comfortable position at intervals of 10cm apart from the patient's mouth and a microphone, and subsequently to phonate a vowel sound /e/ for the maximum phonation time with natural tone and vocal volume then the sound was directly inputted on a computer. During recording, sampling rate was set to 44,100Hz and the 1-second area corresponding to stable zone except the first and the last stage of waveform of the vowel sound /e/ vocalized by the individual patients was analyzed. Results: First, there was no statistically significant difference in jitter and shimmer between vocal fold paralysis and vocal fold cyst, while there was highly statistically significant difference in them between vocal fold paralysis and vocal nodule/polyp. Second, looking into the mean values obtained from NNE, HNR and SNR results associated with noise ratio, the disease showing the most abnormal characteristics was vocal fold paralysis, followed by cyst and nodule/polyp in order. For NNE, there was statistically significant difference between vocal nodule/polyp, and cyst or paralysis. In other words, it was found that the NNE of vocal nodule/polyp was weaker than that of cyst or paralysis. Similarly, HNR and SNR also showed the same characteristics; there was statistically significant difference between vocal fold paralysis and vocal fold cyst or nodule/polyp, and HNR and SNR values of vocal fold paralysis were lower than those of vocal fold cyst or nodule/polyp. Conclusion: For vocal fold paralysis, the abnormal values of acoustic parameters associated with frequency, amplitude and noise ratio were statistically significantly higher than those of vocal fold cyst and nodule/polyp. This finding suggests that the voices of the patients with vocal fold paralysis are the most severely injured due to less stability of vocal fold movement, asymmetry and incomplete glottic closure. In addition, there was no statistically significant difference in the acoustic parameters of tremor among vocal fold paralysis, vocal fold cyst and vocal nodule/polyp. Further studies need to ascertain reasonable acoustic parameters with various vocal disorders as well as to clarify the correlation between acoustics-based objective tools and subjective evaluations.

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Investigation into influence of sound absorption block on interior noise of high speed train in tunnel (터널 내부 도상 블록형 흡음재의 고속철도차량 내부 소음에 미치는 영향에 대한 고찰)

  • Lee, Sang-heon;Cheong, Cheolung;Lee, Song-June;Kim, Jae-Hwan;Son, Dong-Gi;Sim, Gyu-Cheol
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.4
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    • pp.223-231
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    • 2018
  • Recently, due to various environmental problems, blast tracks in tunnel are replaced with concrete tracks, but they have more adverse effects on noise than blast tracks so that additional noise measures are needed. Among these measures, sound-absorbing blocks start to be used due to its easy and quick installation. However, the performance of sound absorption blocks need to be verified under real environmental and operational conditions. In this paper, interior noise levels in KTX train cruising in Dalseong tunnel are measured before and after the installation of sound-absorbing blocks and the measured data are analyzed and compared. Additionally, noise reduction are estimated by modeling the high speed train, the tunnel and absorption blocks. Measurement devices and methods are used according to ISO 3381 and the equivalent sound pressure levels during the cruising time inside the tunnel are computed. In addition to overall SPLs(Sound Pressure Levels), 1/3-octave-band levels are also analyzed to account for the frequency characteristics of sound absorption and equipment noise in a cabin. In addition, to consider the effects of train cruising speeds and environmental conditions on the measurements, the measured data are corrected by using those measured during the train-passing through the tunnels located before and behind the Dalseong tunnel. Analysis of measured results showed that the maximum noise reduction of 6.8 dB (A) can be achieved for the local region where the sound-absorbing blocks are installed. Finally, through the comparison of predicted 1/3-octave band SPLs for the KTX interior noise with the measurements, the understanding of noise reduction mechanism due to sound-absorbing blocks is enhanced.

Preliminary Study on the Development of a Platform for the Optimization of Beach Stabilization Measures Against Beach Erosion III - Centering on the Effects of Random Waves Occurring During the Unit Observation Period, and Infra-Gravity Waves of Bound Mode, and Boundary Layer Streaming on the Sediment Transport (해역별 최적 해빈 안정화 공법 선정 Platform 개발을 위한 기초연구 III - 단위 관측 기간에 발생하는 불규칙 파랑과 구속모드의 외중력파, 경계층 Streaming이 횡단표사에 미치는 영향을 중심으로)

  • Chang, Pyong Sang;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.6
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    • pp.434-449
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    • 2019
  • In this study, we develop a new cross-shore sediment module which takes the effect of infra-gravity waves of bound mode, and boundary layer streaming on the sediment transport into account besides the well-known asymmetry and under-tow. In doing so, the effect of individual random waves occurring during the unit observation period of 1 hr on sediment transport is also fully taken into account. To demonstrate how the individual random waves would affect the sediment transport, we numerically simulate the non-linear shoaling process of random wavers over the beach of uniform slope. Numerical results show that with the consistent frequency Boussinesq Eq. the application of which is lately extended to surf zone, we could simulate the saw-tooth profile observed without exception over the surf zone, infra-gravity waves of bound mode, and boundary-layer streaming accurately enough. It is also shown that when yearly highest random waves are modeled by the equivalent nonlinear uniform waves, the maximum cross-shore transport rate well exceeds the one where the randomness is fully taken into account as much as three times. Besides, in order to optimize the free parameter K involved in the long-shore sediment module, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach from 2017.4.26 to 2018.4.20 as well, and proceeds to optimize the K by comparing the traced shoreline change with the measured one. Numerical results show that the optimized K for Mang-Bang beach would be 0.17. With K = 0.17, via yearly grand circulation process comprising severe erosion by consecutively occurring yearly highest waves at the end of October, and gradual recovery over the winter and spring by swell, the advance of shore-line at the northern and southern ends of Mang-Bang beach by 18 m, and the retreat of shore-line by 2.4 m at the middle of Mang-Bang beach can be successfully duplicated in the numerical simulation.

Effects of light intensity and temperature on photosynthesis and respiration of Panax ginseng leaves (인삼엽(人蔘葉)의 광합성(光合成)과 호흡(呼吸)에 미치는 광도(光度) 및 온도(溫度)의 영향(影響))

  • Park, Hoon;Lee, Chong-Hwa;Bae, Hyo-Won;Hong, Young-Pyo
    • Korean Journal of Soil Science and Fertilizer
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    • v.12 no.1
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    • pp.49-53
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    • 1979
  • Effects of temperature and light intensity on photosynthesis, respiration and chlorophyll content of ginseng (Panax ginseng C. A. Meyer) were as follow. 1. Optimum light intensity for apparent photosynthesis at $25^{\circ}C$ was 25Klux($1.35mgCO_2/dm^2{\cdot}hr$) for two years old ginseng grown in pot and 30Klux($1.94mgCO_2/dm^2{\cdot}hr$) for the six years old palmate cut leaves. Optimum temperature at 25Klux was $15^{\circ}C$ ($1.40mgCO_2$) for the 2 years old and 20 to $22^{\circ}C$ ($2.03mgCO_2$) for the 6 years old. 2. Dark respiration increased almost linearly with the increase of air temperature till $25^{\circ}C$ (2.6times between $16^{\circ}C$ to $25^{\circ}C$ for the 6 years old and 1.8 times between $15^{\circ}C$ to $25^{\circ}C$ for the 2 years old). Dark respiration was 11.1 % of net photosynthesis at $16^{\circ}C$, 17.8% at $25^{\circ}C$ for the 6 years old and 40% at $15^{\circ}C$, 64.7% at $25^{\circ}C$ for 2 years old. 3. Stomata appeared only in abaxial surface (lower epidermis) and stomatal frequency was $37per\;mm^2$. 4. Above results together with other informations quoted here strongly suggest that air temperature is much better criteria than light intensity for the improvement of shading roof material and shading construction. That is to promise maximum light intensity unless air temperature is above $25^{\circ}C$.

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