7,675 research outputs found

    Performance of Ceriporiopsis SP. in the Treatment of Black Liquor Wastewater

    Full text link
    High amounts of black liquor wastewater are generated from bioethanol production by using oil palm empty fruit bunches. It contains an alkaline solution (NaOH), so it is quite toxic for aquatic ecosystems if discharged directly into waters. Black liquor has been treated by coagulation method, and it still needs additional treatment. This study aimed to determine degradation of black liquor wastewater by selected white-rot fungi (WRF). Five different strains of WRF have been tested for their ability to decolorize black liquor on agar and liquid media. Out of five fungi studied, two fungi, Ceriporiopsis sp. and Phanerochaete chrysosporium, showed the capacity to grow more than 50% on agar medium. In liquid medium, the percentage of decolorization of 15,000 ppm coagulated and diluted black liquor ranged from 70 to 89% at 30 days depending on the fungal strain. Ceriporiopsis sp. showed the better ability to decolorize black liquor than P. chrysosporium. The performance of Ceriporiopsis sp was evaluated regarding decolorization of black liquor, chemical oxygen demand (COD), and mycelial dry weight both in coagulated black liquor and original black liquor. The color of original and coagulated black liquor can be decolorized up to 90.13 and 86.85%, respectively. COD in original and coagulated black liquor was reduced up to 70.17 and 40.09%, respectively. The presence of coagulant Poly Aluminum Chloride (PAC) inhibited degradation of black liquor by fungus. The result demonstrated that Ceriporiopsis sp has a potential alternative to treat black liquor wastewater

    Social Entrepreneurs and Innovation for the Unemployment

    Full text link
    This research explored the social entrepreneurship factors to reduce the rate of unemployment in North Sumatra Indonesia. Social entrepreneurship is built through four main elements, namely social value, civil society, innovation, and economic activity. Through the element of innovation, a new form of social entrepreneurship was discovered. Theoretical reviews of social entrepreneurship practices that have been applied in various elements of civil society show innovation elements. An effort to overcome unemployment in Medan Municipality many forms of Social Entrepreneurships were analyzed. Social entrepreneurship that is most appropriately adopted in the city of Medan to reduce unemployment is to empower young women. It concluded that the synergic forms of Social Entrepreneurship with universities, banking institutions and the government, elements of social entrepreneurship including social value, civil society, innovation and economic activity

    Estimates of Genetic and Phenotypic Trends of Growth Traits in Bali Cattle

    Full text link
    The aim of this study was to estimate genetic and phenotypic trends for growth traits including birth (BW), weaning (WW) and yearling weight (YW) in Bali cattle. The number of cattle used to determine growth traits of BW, WW, and YW were 235, 215, and 178 heads, respectively. Estimation of breeding value, phenotypic and genetic correlation were calculated by Restricted Maximum Likelihood and General Linier Model (GLM) procedures, respectively. Genetic trends analysis was performed using the regression mean breeding values on birth year. Phenotypic and genetic correlation among BW and WW were 0.10 and 0.08 respectively and 0.90 and 0.70 for WW and YW respectively. The phenotypic trends for traits of birth and weaning weight were constant, whereas yearling weight was fluctuating from 2000 to 2008. Likewise, in the case of genetic trends, the birth and weaning weight were constant from 2000 to 2008 except for WW in 2005, whereas the genetic trends for yearling weight showed a fluctuation of wide range. According to the breeding value estimated for all traits, the best was the sire No. 0565, whose breeding value for BW, WW and YW were +0.07, +2.79, and +10.25 kg, respectively higher than the mean value of the population. The genetic trends showed that there have been a significant and positive genetic improvement in all growth traits and indicate that selection would be effective. Genetic correlation between WW and YW was high (0.70) which indicates that the selection on weaning weight might also increase yearling weight in Bali cattle

    The Effect of Problem Posing Approach Towards Students\u27 Mathematical Disposition, Critical & Creative Thinking Ability Based on School Level

    Full text link
    The background of this study is the school of the new students of mathematics education courses came from grade high, medium and low. Here the writer wants to see how much influence of the school level on new students\u27 critical thinking skills and creative mathematical. The purpose of this study was to examine differences in new students\u27 mathematical disposition, critical & creative thinking ability through the mathematical problem posing approach based on school level (high, medium, low). The method used in this research is the experimental method, with only posttest design. The population of this study is all the students of mathematics education department in Cimahi; while the sample is selected randomly from one college. Then from this chosen college is taken two samples from random class. The instrument of essay test is used to measure students\u27 critical and mathematical creative thinking ability; while non-test instrument is questionnaire of attitude scale. The results show that: 1) based on the school level (high, medium, and low); there is difference in students\u27 mathematical critical thinking ability through problem posing approach. 2) based on the school level (high, medium, and low); there is difference in the students\u27 mathematical critical thinking ability through problem posing approach. 3) based on the school level (high, medium, and low); there is difference in students\u27 mathematical disposition

    Blended-Learning: the Responses From Non-English Students in the Indonesian Tertiary Context

    Full text link
    The process of language teaching and learning has undergone major changes due to the developments of technology. The use of technology in education field has paved the way for higher education institution to innovatively shape their modern media in a language teaching and learning. Subsequently, the implementation of blended-learning has aroused at the Universitas Teknokrat Indonesia for approximately one and a half year ago to maximize the use of technology. Most lecturers in all study programs have increasingly utilized the social network sites such as Instagram, Facebook, WhatsApp, etc. for the successfulness of blended-learning. This present study aims at exploring the students' responses on how blended-learning might be used to develop their language learning and discovering their attitudes towards the implementation of blended-learning as an interactional teaching and learning tool in English for Business course. Employing a qualitative in form of a case study, eighty-two undergraduate students from study program of Informatics Engineering were observed, interviewed, and distributed questionnaires. The data were performed to collect the students' responses and students' attitudes toward the implementation of blended-learning in the process of their language learning. The findings were found out that most students from Informatics Engineering major showed their positive responses and positive attitudes using blended learning for the language teaching and learning. They also gained some educational benefits for their English language development. Thus, this blended learning brings us to the new trend for language teaching and learning media in order to motivate the students in enhancing their language acquisition

    Power Density Spectra of Gamma-Ray Bursts in the Internal Shock Model

    Get PDF
    We simulate Gamma-Ray Bursts arising from internal shocks in relativistic winds, calculate their power density spectrum (PDS), and identify the factors to which the PDS is most sensitive: the wind ejection features, which determine the wind dynamics and its optical thickness, and the energy release parameters, which give the pulse 50-300 keV radiative efficiency. For certain combinations of ejection features and wind parameters the resulting PDS exhibits the features observed in real bursts. We found that the upper limit on the efficiency of conversion of wind kinetic energy into 50-300 keV photons is ∼\sim 1%. Winds with a modulated Lorentz factor distribution of the ejecta yield PDSs in accord with current observations and have efficiencies closer to 10−310^{-3}, while winds with a random, uniform Lorentz factor ejection must be optically thick to the short duration pulses to produce correct PDSs, and have an overall efficiency around 10−410^{-4}.Comment: 6 pages, 4 figures, Latex, submitted to The Astrophysical Journal (05/04/99

    On The Synchrotron Self-Compton Emission from Relativistic Shocks and Its Implications for Gamma-Ray Burst Afterglows

    Get PDF
    We consider the effects of inverse Compton scattering of synchrotron photons from relativistic electrons in GRB afterglows. We compute the spectrum of the inverse Compton emission and find that it can dominate the total cooling rate of the afterglow for several months or even years after the initial explosion. We demonstrate that the presence of strong inverse Compton cooling can be deduced from the effect it has on the time-evolution of the cooling break in the synchrotron spectral component, and therefore on the optical and X-ray afterglow lightcurves. We then show how the physical interpretation of the observed characteristics of the synchrotron spectrum must be modified to take into consideration this extra source of cooling, and give a revised prescription for computing physical parameters characterizing the expanding shock wave from the observed quantities. We find that for a given set of observables (synchrotron break frequencies and fluxes) there is either no consistent physical interpretation or two of them. Finally we discuss the prospects of directly detecting the inverse Compton emission with Chandra. We argue that such a detection is possible for GRBs exploding in a reasonably dense (n>1 cm^-3) medium.Comment: 21 pages, ApJ submitte

    Yield Performance of Locally Selected Cocoa Clones in North Luwu

    Get PDF
    Participatory selection in North Luwu District selected some locally cocoa clones, of which MCC 01 and MCC 02 the most promising to be developed as clonal material. This research has objectives to observe the stability performance of yield of these clones that enable be characterized of the potency as the basis for recommendation. Observation were carried out in 35 selected-farms be differentiated according to clone\u27s type, namely MCC 01, MCC 02 and Sulawesi 01 (control) and the year of planting (age). These farms were establised at the main area of cocoa in North Luwu. The assessed variables were the number of pod, yield components, the resistance to cocoa pod borer (CPB), vascular-streak dieback (VSD) and phytophthora pod rot (PPR). Data were recorded through 20 sampled-trees per farm in the period of April 2013 to April 2014 with monthly basis assessment. Data were analyzed refer to Eberhart & Russel method to perform stability parameters of the yield. The results indicate that these clones stable performing yield potency among plant age. MCC 01 and MCC 02 performed yield potency in amount of 3,682 kg/ha and 3,132 kg/ha respectively higher than Sulawesi 01 of 2,772 kg/ha. Evaluation of the resistance, MCC 01 having moderate resistance to CPB and VSD and resistance to PPR, however MCC 02 having resistance to CPB, VSD and PPR. Referring to the potency thus MCC 01 and MCC 02 were legally recommended as clonal material for farmers, restricted at the agroclimatic area similar to the condition in North Luwu
    • …
    corecore