• Title/Summary/Keyword: $H_2S$ yield

Search Result 1,157, Processing Time 0.037 seconds

Effects of Varying Nutritional and Cultural Conditions on Growth of the Ectomycorrhizal Fungus Pisolithus tinctorius SMF

  • Suh, Hyung-Won;Don L. Crawford
    • Journal of Microbiology and Biotechnology
    • /
    • v.1 no.2
    • /
    • pp.121-125
    • /
    • 1991
  • The culture conditions and nutritional requirements for enhanced mycelial growth of the ectomycorrhizal fungus P. tinctorius SMF were determined in flask scale experiments. Optimum culture conditions for growth of P. tinctorius SMF in a further modified Melin-Norkrans broth were as follows; temperature 25~$27^{\circ}C$, agitation 120 rpm, and pH 4.0. P. tinctorius SMF utilized various carbon sources including monosaccharides, disaccharides, and polysaccharides. D-Glucose and mannitol were respectively the first and second most suitable carbon sources for mycelial growth. With D-Glucose as the principal carbon source, supplementation of modified Melin-Norkrans (MMN) broth with Lysine (800 mg/l), Glutamic Acid (500 mg/l), or Proline (50 mg/l) enhanced mycelial yields 63%, 34%, and 22% respectively as compared to growth in medium lacking amino acids. ThiaminㆍHCl+biotin+pyridoxine supplementation also enhanced growth. As compared to mycelial growth in the MMN medium, growth of P. tinctorius SMF was enhanced 120% in MMN broth when the carbon/nitrogen ratio was 25/1 in citrate buffer at pH 4.5, and growth was 50% greater in MMN broth of carbon/nitrogen ratio with a 10/1~20/1 without using the buffer. Standard conditions established for growth of P. tinctorius SMF in MMN broth were 25~$27^{\circ}C$, agitation 120 rpm, buffered to pH 4.0 with citrate, in MMN medium containing 10 g/l D-glucose supplemented with 800 mg/l lysine. In this medium the carbon/nitrogen ratio was 20/1~25/1, and the maximal mycelial yield ($Y_{x/s}$ ) was 0.472 (4.72 mg/ml) after 7 days of incubation, as compared to 0.214 (2.14 mg/ml), when the fungus was grown in standard MMN broth.

  • PDF

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF HOT-DEFORMED AlMg4 ALLOYS WITH THE VARIATIONS OF Mn, Fe, AND Si CONTENTS

  • DA B. LEE;BONG H. KIM;KWEON H. CHOI;SEUNG Y. YANG;NAM S. KIM;SEONG H. HA;YOUNG O. YOON;HYUN K. LIM;SHAE KIM;SOONG K. HYUN
    • Archives of Metallurgy and Materials
    • /
    • v.65 no.4
    • /
    • pp.1255-1259
    • /
    • 2020
  • This paper aims to investigate the microstructural evolution and mechanical properties of hot-deformed AlMg4 alloys with Mn, Fe, and Si as the main impurities. For this purpose, solidification behavior and microstructural evolution during hot-rolling and heat-treatment processes are investigated by using theoretical calculations and experimental characterization. The crystallization and morphological transformation of intermetallic Al3Fe, Al6Mn, and Mg2Si phases are revealed and discussed in terms of the variation in chemical composition. Following a homogenization heat-treatment, the effect of heat treatment on the intermetallic compounds is also investigated after hot-rolling. It was revealed that the Mg2Si phase can be broken into small particles and spherodized more easily than the Al3Fe intermetallic phase during the hot-rolling process. For the Mn containing alloys, both yield and ultimate tensile strength of the hot-rolled alloys increased from 270 to 296 MPa while elongation decreased from 17 to 13%, which can be attributed to Mn-containing intermetallic as well as dispersoid.

Synthesis of Neplanocin A Analog with 2′-“up”-C-Methyl Substituent as Potential Anti-HCV Agent

  • Lee, Hyung-Rock;Kang, Jin-Ah;Park, Ah-Young;Kim, Won-Hee;Chun, Pu-Soon;Kim, Jung-Su;Kim, Jin-Ah;Lee, Bo-Eun;Jeong, Lak-Shin;Moon, Hyung-Ryong
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.9
    • /
    • pp.2043-2050
    • /
    • 2009
  • 2′-$\beta$-C-Methylneplanocin A (3) was synthesized via 2-$\beta$-C-methylribonolactone, prepared by a modified Whistler and BeMiller’s method developed by our laboratory, as potential anti-HCV agent. Reduction of 14 with Dibal-H afforded 26 in a good yield with a trace of 25, whereas a Luche reduction gave 26/25 = 4/1 mixture. Several attempts were made to chemoselectively remove TBS group in the presence of TBDPS group and treatment with both PPTS and TsOH showed the best result. Condensation of 26 with 6-chloropurine under Mitsunobu conditions produced an $S_N$2 product 27 along with an $S_N$2′ product 28.

Effects of V and C additions on the Thermal Expansion and Tensile Properties of a High Strength Invar Base Alloy (고강도 인바계 합금의 열팽창 및 인장 특성에 미치는 바나듐과 탄소 원소 첨가 영향)

  • Yun, A.C.;Yun, S.C.;Ha, T.K.;Song, J.H.;Lee, K.A.
    • Transactions of Materials Processing
    • /
    • v.24 no.1
    • /
    • pp.44-51
    • /
    • 2015
  • The current study seeks to examine the effects of V and C additions on the mechanical and low thermal expansion properties of a high strength invar base alloy. The base alloy (Fe-36%Ni-0.9%Co-2.75%Mo-0.7Cr-0.23Mn-0.17Si-0.3%C, wt.%) contains $Mo_2C$ carbides, which form as the main precipitate. In contrast, alloys with additions of 0.4%V+0.3%C (alloy A) or 0.4%V+0.45%C (alloy B) contain $Mo_2C$+[V, Mo]C carbides. The average thermal expansion coefficients of these high strength invar based alloys were measured in the range of $5.16{\sim}5.43{\mu}m/m{\cdot}^{\circ}C$ for temperatures of $15{\sim}230^{\circ}C$. Moreover, alloy B showed lower thermal expansion coefficient than the other alloys in this temperature range. For the mechanical properties, the [V, Mo]C improved hardness and strengths(Y.S. and T.S.) of the high strength invar base alloy. T.S.(tensile strength) and Y.S.(yield strength) of hot forged alloy B specimen were measured at 844.6MPa and 518.0MPa, respectively. The tensile fractography of alloy B exhibited a ductile transgranular fracture mode and voids were initiated between the [V, Mo]C particles and the matrix. Superior properties of high strength and low thermal expansion coefficient can be obtained by [V, Mo]C precipitation in alloy B with the addition of 0.4%V and 0.45%C.

High-Yield Production of Astragalosides from Transgenic Hairy Root Cultures of Astragalus membranaceus (형질전환된 황기 모상근으로부터 Astragalosides의 생산을 위한 연구)

  • Hwang, Sung-Jin
    • KSBB Journal
    • /
    • v.21 no.2
    • /
    • pp.123-128
    • /
    • 2006
  • A transgenic hairy root clone AG-04 of Astragalus membranaceus was obtained following co-cultivation of leaf explants with Agrobacterium rhizogenes ATCC15834. This clone was examined for its growth and production of cyclolanostane-type saponins, astragalosides I, II, and III, under various culture conditions. Among the five basal media tested, Shenk and Hildebrandt(SH)(18) medium was best for roots growth and astragalosides production. The maximum root biomass was obtained at inoculum size of 500 mg FRW per flask, initial sucrose concentration of 3%, and shaking speeds of 90 rpm. The astagalosides production was promoted when the hairy root clone AG-04 was cultured at shaking speeds of 120 rpm and light irradiation of 18 h. Astragaloside contents was also stimulated with high initial sucrose concentration, and the maximum astargalosides contents of 6.21 %/g DRW was obtained at initial sucrose concentration of 6%. The addition of chitosan(100 mg/L) to the culture medium was significantly increased astragalosides production. This was 2.1 times higher than that obtained in a control culture without chitosan.

Characteristics of Soil Parameter for Lade's Single Work-Hardening Constitutive Model with Relative Density of Bottom ash (석탄회의 상대밀도에 따른 Lade 단일항복면 구성모델의 토질매개변수 특성)

  • Kim, Chan-Kee;Lee, Jong-Cheon
    • Journal of the Korean Geosynthetics Society
    • /
    • v.12 no.4
    • /
    • pp.87-98
    • /
    • 2013
  • This study was performed a series of the isotropic compression-expansion tests and the drained triaxial tests with various the relative densities 40%, 60%, 80% and 95% for bottom ash. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. The soil parameters Kur and n representing elastic behavior are not much affected by the change of the relative density. The other parameters such as failure criterion(m, ${\eta}_1$), hardening function(c, p) and plastic potential(${\psi}_2$, ${\mu}$) are in a positive linear relationship with the relative density. Since the soil parameters h and ${\alpha}$ representing yield function do not change much to the change of relative density and also closely related to failure criterion, they can be replaced by failure criterion ${\eta}_1$. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data.

Characteristics of Soil Parameter for Lade's Single Work-Hardening Constitutive Model with Dry Density of Pocheon Granite Soil (포천 화강토의 건조단위중량에 따른 Lade의 단일항복면 구성모델의 토질매개변수 특성)

  • Cho, Won-Beom;Kim, Chan-Kee
    • Journal of the Korean Geosynthetics Society
    • /
    • v.10 no.4
    • /
    • pp.29-36
    • /
    • 2011
  • In this study, a series of the isotropic compression-expansion tests and the drained triaxial tests were performed on Pocheon granite soil with various the dry densities of $16.67kN/m^3$, $17.26kN/m^3$ and $17.65kN/m^3$. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. The soil parameters such as kur and n related to elastic behavior, m and ${\eta}_1$ related to failure criterion, c and p related to hardening function and ${\psi}_2$ and ${\mu}$ related to plastic potential show in a positive linear relationship with the dry density. Since the soil parameters h and representing yield function do not change much to relative density and also are closely related to failure criterion, they can be replaced by failure criterion. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data.

Development of Substrate and Cultural Method for the Cultivation of Pleurotus sajor-caju (느타리 버섯(Pleurotus sajor-caju) 재배를 위한 기질 및 재배방법의 개발)

  • Hong, B.S.;Kim, S.J.;Song, C.H.;Hwang, S.Y.;Yang, H.C.
    • The Korean Journal of Mycology
    • /
    • v.20 no.4
    • /
    • pp.354-359
    • /
    • 1992
  • The effect of the addition of various vegetable oils on the mycelial growth was studied. Most vegetable oils were proved to be stimulative for the mycelial growth, and the best mycelial growth (12 mg/ml) was obtained with the addition of cotton seed oil. Several agricultural wastes i.e., rice straw, peanut hull, sawdust, rice hull, cocoa hull, coffee waste and beer waste were empolyed as substrates for sporophore production of p. sajor-caju. The biological efficiency(BE) for sporophore productions of rice straw and peanut hull were 36.4% and 32.6%, respectively. The highest yield of sporophore was obtained from the mixture of rice straw (50%) and beer waste (50%)(BE 109.6%) followed by peanut hull (50%) and beer waste (50%)(BE; 74.5%).

  • PDF

Characteristics of Soil Parameter for Lade's Single Work-Hardening Constitutive Model with Relative Density of Baekma River Sands (백마강 모래의 상대밀도에 따른 Lade의 단일항복면 구성모델의 토질매개변수 특성)

  • Cho, Won-Beom;Kim, Chan-Kee;Kim, Joong-Chul
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.1C
    • /
    • pp.11-17
    • /
    • 2011
  • This study was performed a series of the isotropic compression-expansion tests and the drained triaxial tests with various the relative densities 25%, 50%, 80% and 100% for Baekma river sand. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. The soil parameters Kur and n representing elastic behavior are not much affected by the change of the relative density. The other parameters such as failure criterion (m, ${\eta}_1$), hardening function (C, p) and plastic potential (${\Psi}_2$, ${\mu}$) are in a positive linear relationship with the relative density. Since the soil parameters h and $\alpha$ representing yield function do not change much to the change of relative density and also closely related to failure criterion, they can be replaced by failure criterion ${\eta}_1$. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data.

Plant Damages and Yields of the Different Rice Cultivars to Brown Planthopper (Nilaparvata lugens S.) in Fields (벼멸구에 의한 벼품종(品種)의 피해(被害)와 수량(收量))

  • Kim, Y.H.;Lee, J.O.;Park, H.C.;Kim, M.S.
    • Korean journal of applied entomology
    • /
    • v.24 no.2 s.63
    • /
    • pp.79-83
    • /
    • 1985
  • Plant damages and yields of the different rice cultivars to brown planthopper (BPR), Nilaparvata lugens S., were observed for the evaluation of varietal resistance in paddy fields. Twenty nine Korean cultivas were transplanted in paddy fields with three plots of no insecticide, no insecticide and fungicide, and no fungicide at Haenam, southern coastal area in 1983. Among 6 varieties with BPR resistant genes, Samgang, Gaya, Hangangchal, and Cheongcheong showed very low populations of BPR and no damages on all treatments. Milyang 30 and Wonpung among them had considerable populations of BPR. Seokwang and 23 others showed high populations and serious damages. Yield increasea(%) with insecticides were low on Gaya(12%), Samgang(29%) and Hangangchal(35%), but very high on Bongkwang(260%), Palgueum(223%), Songjeon(200%), and Guanauk(200%).

  • PDF