• Title/Summary/Keyword: Densities

Search Result 3,409, Processing Time 0.032 seconds

Treatment of Cow manure by Vermicomposting 1. Effect of population densities on the growth and reproduction of the earthworm(Eisenia foetida) (Vermicomposting에 의한 우분의 처리 1. 사육밀도가 지렁이의 생육과 증식에 미치는 영향)

  • Lee, J.S.;Kim, S.J.;Cho, G.Y.
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.1 no.2
    • /
    • pp.259-266
    • /
    • 1993
  • This experiment was carried out to the effect of population densities on the growth reproduction, cast production of the earthworm and chemical composition of worm casts. The population densities of 50, 100, 150, 200 and 250 individuals of the earthworm fed with cow manure was studied in rearing box($6,400cm^3$) and fertility stage during a period of 60 days. The results were summarized as follows 1. Survival rates(SR) of the earthworms had significantly positive correlated with increasing rate(IR). But, survival rates(SR) and increasing rate(IR) had significantly negative correlated with reproductive efficiency(RE). 2. The ranges of optimum population densities estimated were $42.7cm^3-128.0cm^3/worm$. 3. The cast production estimated were 36.5mg-80.9mg/day/worm grown in optimum population densities(50-150 worms/$6,400cm^3$). 4. The earthworm castings are an excellent soil conditioning material with a high chemical composition and their physical properties.

  • PDF

Treatment of Cow Manure by Vermicomposting -Effects of population density and C/N ratios of feed on the growth and cast production of the earthworm(Eisenia foetida)- (Vermicompositing에 의한 우분의 처리 -먹이의 탄질율과 사육밀도가 지렁이의 생육과 분립의 생산에 미치는 영향-)

  • Lee, Ju-Sam
    • Journal of Animal Environmental Science
    • /
    • v.1 no.1
    • /
    • pp.65-75
    • /
    • 1995
  • This experiment was carried out to the effects of population density and C/N ratios of feed on the growth, reproductive effciency and cast producation of the earthworm(Eisenia foetida). The population densities of 50, 100, 150, 200 and 250 individuals of the earthworm fed with different C/N ratios of 25, 35, 45 and 55 cow manures were studied in rearing box($6,400cm^3$), and at the fertility stage during a period of 60 days. The results were summarized as follows; The survial rate(SR), increasing rate(IR), reproductive efficiency(RE) and cast production of the earthworms showed highest values in C/N ratio of 25. These results may indicate that C/N ratio of 25 is a very favourable feed for the growth of the earthworms. The survial rate(SR) indicated significant positive correlation with reproductive efficiency(RE) in different C/N ratios of feeds. The survial rate(SR) showed highest values in population densities of $50{\sim}100$ worms/$6,400cm^3(64.0{\sim}128.0cm^3/worm$). On the contrary, increasing rate(IR) tended to decreased with the increased population densities. The survival rate(SR) indicated significant negative correlation with reproductive efficiency(RE) in different population densities of the earthworms. The cast production estimated were $31.6mg{\sim}67.4mg/day/worm$ grown in optimum population densities($50{\sim}100\;worms/6,400cm^3$). The earthworm casting are an excellent soil conditioning material or organic fertilizer sources with a high chemical composition and their physical properties.

  • PDF

Effects of Planting Density and Fertilizer Level on Agronomic Characteristics and Yield of Solanum njgrum L. (재식밀도와 시비량이 야생약초 까마중(Solanum njgrum L.)의 주요 형질과 수량에 미치는 영향)

  • 최성규;이종일
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.36 no.4
    • /
    • pp.340-344
    • /
    • 1991
  • This study was investigated to find out the optimum planting densities fo Solanum njrum L. about growth characters. yield components and yield at 6 planting densities by direct sowing culture. The results obtained are summarized as follows: Studying the correlationship. the highly negative significances were found between planting densities and fresh eights weights per plant, on the other hand, the highly positive significances were found between planting densities and plant height. Plant height was long in dense planting, and short in spacious planting by direct sowing culture. Stem diameter was thick in spacious planting. and was thin in dense planting. Fresh wt. per plant was decreased in dense planting and was increased in spacious planting by direct sowing culture. Yield was highest in dense planting densities (10 x 20cm : 50plants/$m^2$) by direct sowing culture. Fertilizing ((N: P$_2$O$_{5}$ $K_2$O=6 : 6 : 6Kg/10a) was increased than without fertilizing because plant height and number of branch was good.d.

  • PDF

Evaluation of preslaughter losses, meat quality, and physiological characteristics of broilers in response to crating density for the standard of animal welfare and to seasonal differences

  • Myunghwan Yu;Elijah Ogola Oketch;Jun Seon Hong;Shan Randima Nawarathne;Yuldashboy Vohobjonov;Jung Min Heo
    • Korean Journal of Agricultural Science
    • /
    • v.49 no.4
    • /
    • pp.927-936
    • /
    • 2022
  • The effects of seasonal differences and crating densities on the preslaughter losses, breast meat quality, and physiological indices of broilers were determined. A total of 600 broilers aged 35 days were divided into 10 treatment groups based on five crating densities (10.3, 11.5, 12.8, 14.1, 15.4 birds·m-2) with two seasons (i.e., summer and winter) to give six replicates and were placed at various locations in the truck. The birds were transported in crates having dimensions of 1.0 m × 0.78 m × 0.26 m. The transportation distance was 20 km for 40 minutes (average 30 - 50 km·h-1) during the early morning. The results revealed that broilers transported at densities of 14.1 and 15.4 birds·m-2 recorded lower (p < 0.05) pH, water-holding capacity (WHC), and muscle redness compared to those at densities of 11.5 birds·m-2. Furthermore, higher (p < 0.05) cooking loss was found in birds stocked at more than 14.1 birds·m-2 compared to the other treatments. However, no effect (p > 0.05) with different crating densities on body weight loss, carcass traits, glucose, lactate, or muscle yellowness was observed. Crating density of 14.1 birds·m-2 showed lower (p < 0.05) cortisol contents compared with birds at 10.3 and 15.4 birds·m-2. Winter transportation had higher (p < 0.05) relative breast meat weight, cooking loss, muscle redness, and cortisol contents whereas summer transportation had higher (p < 0.05) glucose and lactate contents in the blood plasma of broilers. In conclusion, the stocking of 12.8 birds·m-2 is recommended to minimize stress responses and undesirable changes that could negatively affect muscle quality.

Application of HMO for Reactivity of the Benzologous Pyridine Ligands (Ⅱ) (Benzologous Pyridine 계 리간드의 반응성에 대한 HMO 의 응용(제 2보))

  • Ja Hong Kim;Gae Soo Lee
    • Journal of the Korean Chemical Society
    • /
    • v.24 no.1
    • /
    • pp.20-24
    • /
    • 1980
  • The frontier electron densities and pK values for benzologous pyridine ligands are calculated using the HMO. Linear regression formula for pK in protonation of ligands is derived from the electron densities and observed pK values. The calculated pK values are in agreement with those of experimental values and a parallelism is shown between pK and qN. The reactivities for electrophilic, nucleophilic and radical reactions have also been calculated respectively by frontier electron densities.

  • PDF

Analyses on Current Densities Induced Inside a Worker Using AC Arc Welder (교류 아크용접기를 사용하는 작업자의 인체 유도전류밀도 해석)

  • Park, Jun-Hyeong;Min, Suk-Won
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.3
    • /
    • pp.433-438
    • /
    • 2008
  • This paper analyses current densities induced inside a worker using AC arc welder. Applying the boundary element method, we calculate current densities induced in organs inside a worker in case he was located at 1cm, 3cm, 5cm, 10cm, 15cm, 20cm far from a power cable of AC arc welder. As results of study, we find a maximum current density induces at a heart surface and may be higher than $10mA/m^2$ of ICNIRP guideline if he works within 15cm from a power cable.

The Distribution and Population Densities of Yeasts and their Epiflora on Seaweeds in Inshore Waters of Mok-po, Korea (한국 목포 연해안해수내의 효모 분포 및 집단밀도와 해조류상의 효모상)

  • 전순배;박명삼
    • Korean Journal of Microbiology
    • /
    • v.13 no.4
    • /
    • pp.157-164
    • /
    • 1975
  • The distribution and population densities of yeasts including their epiflora on seaweeds were estimated over two months in inshore waters of Mok-po, Korea. Nine species of 48 isolates were obtained from this area. Rhodotorula, Torulopsis and Debaryomyces that are widespread in estuaries were of common occurrence in this water body. The highest counts belonged to Torulopsis candida which was predominated in temperate estuarine zone. The distribution of sea weeds seems to be correlated with the population densities of yeasts. Two species of marine algae harbored yeasts during May and July, 1975. Among seaweeds isolates, the highest numbers werre of the species Rhodotorula glutinis var. glutinis. A dominant colonization of this strain on Chlorophyceae and Phaeophyta and a role of water temperature for the growth of yeasts are discussed.

  • PDF

A Study on the Mechanical Properties to the Weight Reduction Rate of PET Fabrics(II) (PET직물의 감량률에 따른 역학적 특성변화에 관한 연구(II))

  • 이희준;이민수;김승진;홍성철;김석근;전계현
    • Textile Coloration and Finishing
    • /
    • v.10 no.6
    • /
    • pp.10-19
    • /
    • 1998
  • This study surveys the mechanical properties such as tensile and compressional properties to the weight reduction rate of PET fabrics with various weft linear densities, weft t.p.m. and desities. 18 kinds of plain and 12 kinds of satin weave fabrics were woven and processed with variation of weight reduction rate(0%, 12%, 25% and 30%) in dyeing and finishing processes. Tensile work, resilience and compressional work and resilience of these finished fabrics treated with different weight reduction rates were measured by KES-FB System and discussed with various wok linear densities, weft t.p.m., densities, and weight reduction rates.

  • PDF

Density of Molten Salt Mixtures of Eutectic LiCl-KCl Containing UCl3, CeCl3, or LaCl3

  • Zhang, C.;Simpson, M.F.
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.15 no.2
    • /
    • pp.117-124
    • /
    • 2017
  • Densities of molten salt mixtures of eutectic LiCl-KCl with $UCl_3$, $CeCl_3$, or $LaCl_3$ at various concentrations (up to 13 wt%) were measured using a liquid surface displacement probe. Linear relationships between the mixture density and the concentration of the added salt were observed. For $LaCl_3$ and $CeCl_3$, the measured densities were significantly higher than those previously reported from Archimedes' method. In the case of $LiCl-KCl-UCl_3$, the data fit the ideal mixture density model very well. For the other salts, the measured densities exceeded the ideal model prediction by about 2%.

Determination of Doping Density in GaAs Semiconductor by Wavelength-Dependent Photoacoustic Spectroscopy

  • Lim, Jong-Tae;Choi, Ok-Lim;Boo, Doo Wan;Choi, Joong-Gill
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.3
    • /
    • pp.895-898
    • /
    • 2014
  • The wavelength dependence of the photoacoustic signal for n-type GaAs semiconductors in the region of the band-gap energies was investigated. The significant changes in the phase and amplitude of the photoacoustic signal near the band-gap absorption wavelengths were observed to occur when the Si-doping densities in GaAs were varied. Particularly, the first derivatives of the photoacoustic phase vs. wavelength graphs were evaluated and fitted with single Gaussian functions. The peak centers and the widths of the Gaussian curves clearly showed linear relationships with the log values of the Si-doping densities in n-type GaAs semiconductors. It is proposed that the wavelength-dependent PA spectroscopy can be used as a simple and nondestructive method for measuring the doping densities in bulk semiconductors.