• Title/Summary/Keyword: $CH_4/N_2$

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Synthesis and Characterization of banana-shaped achiral molecules

  • Lee, Chong-Kwang;Lee, Chong-Kwang;Kwon, Soon-Sik;Kim, Tae-Sung;Shin, Sung-Tae;Choi, Suk;Choi, E-Joon;Kim, Sea-Yun;Kim, Jae-Hoon;Zin, Wang-Choel;Kim, Dae-Cheol;Chien, Liang-Chy
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.504-508
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    • 2003
  • New banana-shaped achiral compounds, 4-chloro-1,3-phenylene bis [4-4(3-fluoro-9-alkenyloxy) phenyl-iminomethylbenzoate]s and 4-chloro-1,3-phenylene bis [4-4-(3-fluoro-10-alkanyloxy) phenyliminomethyl benzoate]s were synthesized by varying the substituent (X=H, F, or Cl); their electrooptical properties are described. The smectic phases, including a switchable chiral smectic C ($SmC^{\ast}$) phase, were characterized by differential scanning calorimetry, polarizing optical microscopy, and triangular method. The presence of vinyl end group at the terminals of linear side wings in the banana-shaped molecules induced a decrease in melting temperature. The smectic phase having the undecenyloxy group such $as-(CH_2)_9CH=CH_2$ showed ferroelectric switching, and its value of spontaneous polarization on reversal of an applied electric field was 2250 $nC/cm^2$, while the value of spontaneous polarization of the smectic phase having the decanyloxy group such as $-(CH2)_9CH_3$ was 3700 $nC/cm^2$. We could obtain the ferroelectric phase with low isotropic temperature by varying the end group at the terminals of linear side wings in the banana-shaped achiral molecules.

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Effects of Cellulase Supplementation on Nutrient Digestibility, Energy Utilization and Methane Emission by Boer Crossbred Goats

  • Wang, Lizhi;Xue, Bai
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.2
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    • pp.204-210
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    • 2016
  • This study examined the effect of supplementing exogenous cellulase on nutrient and energy utilization. Twelve desexed Boer crossbred goats were used in a replicated $3{\times}3$ Latin square design with 23-d periods. Dietary treatments were basal diet (control, no cellulase), basal diet plus 2 g unitary cellulase/kg of total mixed ration dry matter (DM), and basal diet plus 2 g compound cellulase/kg of total mixed ration DM. Three stages of feeding trials were used corresponding to the three treatments, each comprised 23 d, with the first 14 d as the preliminary period and the following 9 d as formal trial period for metabolism trial. Total collection of feces and urine were conducted from the 4th d of the formal trial, and gas exchange measures were determined in indirect respiratory chambers in the last 3 d of the formal trial. Results showed that cellulase addition had no effect (p>0.05) on nutrient digestibility. Dietary supplementation of cellulase did not affect (p>0.05) N intake and retention in goats. Gross energy (GE) intake, fecal energy and urinary energy excretion, heat production were not affected (p>0.05) by the cellulase supplementation. Total methane emission (g/d), $CH_4$ emission as a proportion of live weight or feed intake (DM, organic matter [OM], digestible DM or digestible OM), or $CH_4$ energy output ($CH_4$-E) as a proportion of energy intake (GE, digestible energy, or metabolizable energy), were similar (p>0.05) among treatments. There was a significant (p<0.001) relationship between $CH_4$ and live weight (y = 0.645x+0.2, $R^2$ = 0.54), $CH_4$ and DM intake (y = 16.7x+1.4, $R^2$ = 0.51), $CH_4$ and OM intake (y = 18.8x+1.3, $R^2$ = 0.51) and $CH_4$-E and GE intake. Results from this study revealed that dietary supplementation of cellulase may have no effect on nutrient digestibility, nitrogen retention, energy metabolism, and methane emission in goat.

Synthesis of N-(Alkyl-N'-nitrosocarbamoyl)-amino Acid Ester Derivatives and their Anticancer Activity (N-(Alkyl-N'-nitrosocarbamoyl)-amino Acid Ester류의 合成 및 抗癌 作用 評價)

  • Kim, Jeong-Gyun;Park, Moon-Tae;Shin, Hong-Dae;Koh, Young-Sim;Yoon, Ung-Chan;Ryu, Sung-Ho;Moon, Kyung-Ho;Kim, Min-Sook
    • YAKHAK HOEJI
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    • v.28 no.4
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    • pp.197-206
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    • 1984
  • The derivatives of N-(alkylcarbamoyl) amino acid methyl ester, N-(2-chloroethylcarbamoyl)-glycine methyl ester (7a), -valine methyl ester (8a), -phenylalanine methyl ester (9a), N-(N'-methylcarbamoyl)-glycine methyl ester (7b), -valine methyl ester (8b), and-phenylalanine methyl ester (9b), were prepared by reacting the corresponding free amino acid methyl ester (glycine-, valine-, phenylalanine-methyl ester) with isocyanate (R-N=C=O${\cdot};R=Cl-CH_2-CH_2-or\; CH_3-)$. The prepared N-(alkylcarbamoyl) amino acid methyl esters (7,8,9) were treated with $NaNO_2$/98% HCOOH in order to obtain their nitrosoated products, N-(alkyl-N'-nitrosocarbmoyl)amino acid methyl ester. The compound (7,8,9) gave N-(2-chloroethyl-N'-nitrosocarbamoyl)-valine methyl ester (14a),-phenylalanine methyl ester (15a), N-(N'-alkyl-N'-nitrosocarbamoyl)-glycine methyl ester (13b),-valine methyl ester. (14b), and-phenylalanine methyl ester (15b) respectively under the nitrosoation. On the other hand, N-(2-chloroethylcarbamoyl) glycine methyl ester produced N-(2-chloroethylcarbamoyl)-N-nitrosoglycine methyl ester (13a). The inhibitory activity of the prepared N-(alkylcarbamoyl) amino acid methyl ester (7,8,9) and N-(alkyl-N'-nitrosocarbamoyl) amino acid methyl ester (13,14,15) towards the growth of L1210 murine leukemia cells were examined. Among them the compound (14a) and (15a) exhibit excellent activity having $ED_{50}\; to\;be\;1.5{\mu}g/ml\;and\;3.0{\mu}g/ml respectively.

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Synthesis and Antitumor Evaluation of Acyclic 1-[${\omega}$-(N^I-2-chloroethyl-N^I-nitrosoureido)alkyl]thymidine Nucleoside Analogues

  • Kim, Jack-C.;Kim, Young-Hyun;Park, Jin-Il;Kim, Seon-Hee;Choi, Soon-Kyu
    • Archives of Pharmacal Research
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    • v.20 no.3
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    • pp.259-263
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    • 1997
  • In the preparation of acyclic thymidine nucleoside analogues, $K_2CO_3$(or NaH) treated thymine in DMSO was alkylated with .omega.-chloroalkyl nitrite (Cl-(CH_2)n-CN; n=1, 2, 3, 4) to provide an isomeric mixture of 1-(${\omega}$-cyanoalkyl)thymine (2a-d) and 1,3-bis(${\omega}$-cyanoalkyl)thymine in approximately 5:1 ratios. Reduction of the cyano function 2a-d with $NaBH_{4}/CoCl_{2}$ center dot$ 6H_{2}O$gave the corresponding 1-(${\omega}$aminoalkyl)thymine (3a-d). The newly formed primary amino function in 3a-d was directly reacted with 2-chloroethylisocyanate to afford the 1-[.omega.($N^{I}$-2-chloroethylureido) alkyl]thymine (4a-d) in good yields. Nitrosation of 1-[5-($ N^{I}-2$-chloroethylureido)pentyl] thymine (4d) with glacial acetic acid and dry $NaNO_{2}$-powder in anhydrous $CH_{2}Cl_{2}$gave two types of regioisomeric nitrosoureas, 1-[5-($N^{I}$--chloroethyl-$N^{I}$--nitrosoureido)pentylithymine (5d) and 1-[5-($N^{I}-2$-chloroethyl-N-nitrosoureido)pentyllthymine in approximately 5 :1 ratios. The in vitro cytotoxicity of the synthesized compounds (2a-d, 3a-d, 4a-d and 5a-d) against three cell lines (K-562, P-388 and FM-3A) are measured as $IC^{50}$ values. Compounds 3b and 4c showed moderate activities against all three cell lines, and all other compounds were found to be not active.

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Theoretical Studies on the Base-Catalyzed Deprotonation of 4-Phenacylpyridinium Cations

  • 김왕기;전영이;손창국;김창곤;이익준
    • Bulletin of the Korean Chemical Society
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    • v.18 no.2
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    • pp.193-197
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    • 1997
  • Theoretical studies on the base-catalyzed deprotonation of 4-phenacylpyridinium cations, R1-CO-CH2-C5H4N-R2, I (R1=YC6H4 -and R2=CH3), and II (R1=C6H5 and R2=CH2C6H4Y) have been carried out with bases, NH3 and XC6H4NH2 using AM1 MO method. The Brψnsted α values are 0.20 and 0.22 and the βB values are 0.62 and 0.61, respectively for cations I and II. The negative Ⅰ (=α-βB) values obtained are in accord with the experimental results in aqueous solution, although the theoretical gas-phase α values for I are somewhat smaller than the experimental values in water due to neglect of solvation effect. It has been stressed that the Brψnsted α is distorted not only by the lag in the resonance and solvation development in the carbanion, but also by the difference in the distance between the anionic center and substituents in the TS and in the product anion.

Relationship between the Methane Production and the CNCPS Carbohydrate Fractions of Rations with Various Concentrate/roughage Ratios Evaluated Using In vitro Incubation Technique

  • Dong, Ruilan;Zhao, Guangyong
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.12
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    • pp.1708-1716
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    • 2013
  • The objective of the trial was to study the relationship between the methane ($CH_4$) production and the Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate fractions of feeds for cattle and the suitability of CNCPS carbohydrate fractions as the dietary variables in modeling the $CH_4$ production in rumen fermentation. Forty-five rations for cattle with the concentrate/roughage ratios of 10:90, 20:80, 30:70, 40:60, and 50:50 were formulated as feed samples. The Menke and Steingass's gas test was used for the measurement of $CH_4$ production. The feed samples were incubated for 48 h and the $CH_4$ production was analyzed using gas chromatography. Statistical analysis indicated that the $CH_4$ production (mL) was closely correlated with the CNCPS carbohydrate fractions (g), i.e. CA (sugars); $CB_1$ (starch and pectin); $CB_2$ (available cell wall) in a multiple linear pattern: $CH_4=(89.16{\pm}14.93)$ $CA+(124.10{\pm}13.90)$ $CB_1+(30.58{\pm}11.72)$ $CB_2+(3.28{\pm}7.19)$, $R^2=0.81$, p<0.0001, n = 45. Validation of the model using 10 rations indicated that the $CH_4$ production of the rations for cattle could accurately be predicted based on the CNCPS carbohydrate fractions. The trial indicated that the CNCPS carbohydrate fractions CA, $CB_1$ and $CB_2$ were suitable dietary variables for predicting the $CH_4$ production in rumen fermentation in vitro.

NOx Formation Characteristics on Heat Loss Rate for CH4/Air Premixed Flames in a Perfectly Stirred Reactor (완전혼합 반응기에서 CH4/Air 예혼합화염의 열손실율에 따른 Nox 생성특성)

  • Hwang, Cheol-Hong;Lee, Kee-Man;Kum, Sung-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.7
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    • pp.1465-1472
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    • 2009
  • The effect of heat loss rate on NOx formation of $CH_4/air$premixed flame were examined numerically in a perfectly stirred reactor. The following conclusions were drawn. Under the adiabatic wall condition, an increase in the residence time causes a remarkable increases in NOx emission. Under the heat loss conditions, however, NOx decreases significantly as the heat transfer coefficient and residence time increase. As the heat loss rate increases, Thermal NO mechanism and Re-burning NO mechanism play an important role in the NOx reduction, but Prompt NO mechanism and $N_2O$-intermediate NO mechanism lead to the increase in NOx production. Although the NOx formation is actually related to complex NOx mechanism with the changes in the heat transfer coefficient and residence time, it was found that NOx concentration can be represented by independent Thermal NO mechanism. From these results, new NOx correlation combined with the heat loss rate and residence time was suggested for predicting the NOx concentration in a practical $CH_4/air$premixed combustor.

Possibilities for Reduction and the Emissions of Trace Gases from Livestock System (축산에서 기후변동 관련 기체의 발생원과 방지대책)

  • 류종원
    • Journal of Animal Environmental Science
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    • v.4 no.1
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    • pp.37-45
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    • 1998
  • There are a lot of trace gas of gaseous pollutants produced from farm animals. CO2 and CH4 are gases produced directly by the animal. NH3, N2O are produced from animal waste. Most of the effects of these gaseous pollutants on the farm animals have not been investigated in detail. CO2 emission from animal is very little. CH4 release from ruminant is also considered to be a significant factor in potential global warming. Nitrous oxide (N2O) emissions could be avoided by using organic or mineral fertilizer only as much as is needed by plant growing. This paper gives an overview about problems and solving strategies for possibilities for reduction of gaseous pollutants. The way to reduce the gaseous pollution risks from livestock systems are discussed.

Measurements of $CH_4$ Flux from Landfill Surface and Theoretical Estimation in Its Emission (매립지 표면으로부터의 $CH_4$ 배출량 측정과 이론적 장래배출량 예측)

  • 김득수;오진만;고현석;두강진;장영기;전의찬
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.04a
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    • pp.200-202
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    • 2000
  • 온실가스의 배출자료는 기후변화협약 참여협상 및 저감대책 수립에 없어서는 안될 중요한 기초자료이다. 그러나 국내에서는 현재 에너지와 농업 분야를 제외하고는 온실가스의 배출원 및 배출량 조사가 미미한 실정이다. 이번 연구에서는 기후변화와 관련된 온실효과에 커다란 기여를 하고 있는 메탄($CH_4$)의 매립지 표면으로부터의 국내 배출량을 조사하고자 한다. $CO_2$, $CH_4$, $N_{2}O$, $O_3$, CFC 등의 주요 온실가스들은 여러 경로를 통해서 대기로 배출되고 있으며, 온실가스의 배출기여도를 보면 도시쓰레기의 매립이 전체 배출량에 약 3%정도 기여하는 것으로 보고되었다. (중략)

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Studies on Oocyte Activation Regimen for Nuclear Transfer in Hanwoo(Korean Cattle) (핵이식을 위한 한우 난자 활성화 처리방법에 관한 연구)

  • 임기순;양보석;박성재;양병철;장원경;박창식
    • Korean Journal of Animal Reproduction
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    • v.24 no.3
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    • pp.281-288
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    • 2000
  • This experiment was carried out to investigate the optimal activation condition for parthenogenetic development. In order to activate oocytes at 22 h post onset of maturation, the oocytes were subjected to 5 $\mu$M ionomycin(I) for 5 min ,10 $\mu$M calcium ionophore(Ca) for 5 min, 2 mM 6-dimethylamino-purine(DMAP) for 3 h and 10 $\mu\textrm{g}$/$m\ell$ cycloheximide(CH) for 6 h alone or in combination. The activated oocytes were cultured in modified CR$_1$aa at 5% $CO_2$, 5% $O_2$, 90% $N_2$. l. The cleavage rates after 48 h culture of oocytes treated with I, Ca, DMAP and CH were 12.7%, 14.1%, 28.9% and 22.9%, respectively. There was no blastocyst formation. 2. The cleavage rates after 48 h culture of oocytes treated with I + DMAP, I + CH, Ca + DMAP and Ca + CH were 96.9%, 82.1%, 93.1% and 34.7%, respectively. Developmental rates to blastocysts were 10.4%, 5.3%, 17.6% and 7.1 %, respectively. When oocytes were treated with Ior Ca followed by DMAP, the blastocyst formation rate was significantly higher than other groups(P <0.05). 3. According to single activation treatment, pronucleus formation rates were 5.4%, 3.6%, 28.3% and 28.8%, respectively, Whereas, all oocytes treated with the combined activation agents formed 100% pronucleus.

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