• Title/Summary/Keyword: scientific research

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On the Study of Foundation and Activity in the Early Scientific Societies (초창기 과학학회의 설립 및 활동에 관한 연구)

  • Yoon, Ill-He
    • Journal of Science Education
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    • v.41 no.2
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    • pp.267-280
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    • 2017
  • The purpose of this study is to review the foundation of the representative early scientific societies and their major activities. The documents, books, and literature related to this study were collected through internet websites (e.g., google scholar, wikipedia) and analyzed by the qualitative content analysis method. The result of this study shows that requirement for the necessary resources to acquire or to prepare the instruments for the experiment is significantly increased with the rising importance of the experiments to conduct the scientific methods. As a consequence, scientists faced urgent necessities to conduct scientific experiments with cooperation and exchange of the newest information by establishing a community beyond the independent and individual research activity. Establishment of the scientific societies is the result of these necessities. At the beginning of the scientific societies, the resources are provided by either wealthy patron or member contribution or public through foundation of government organization. This study provides the implications for future scientific societies.

Synthesis of Activated Carbon from a Bio Waste (Flower of Shorea Robusta) Using Different Activating Agents and Its Application as Supercapacitor Electrode

  • Ghosh, Souvik;Samanta, Prakas;Murmu, Naresh Chandra;Kim, Nam Hoon;Kuila, Tapas
    • Composites Research
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    • v.35 no.1
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    • pp.1-7
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    • 2022
  • The activated carbon is a very good choice for using as supercapacitor electrode materials. Herein, the flower of Shorea robusta, a bio-waste material was successfully used to synthesize the activated carbons for application as supercapacitor electrode materials. The activated carbon was synthesized through chemical activation process followed by thermal treatment at 700℃ in presence of N2 atmosphere using KOH, ZnCl2 and H3PO4 as the activating agents. The physicochemical analyses demonstrate that the obtained activated carbons are graphitic in nature and the degree of disorder of the graphitic carbons is changed with the activating agents. The activated carbon obtained from Shorea robusta flower (ACSF-K) electrode shows the specific capacitance of ~610 F g-1 at 2 A g-1 current density, which is higher than ACSF-Z (560 F g-1) and ACSF-H (470 F g-1) electrode material under the identical current density. The synthesized graphitic carbons also demonstrated good rate capability and high electrochemical stability as supercapacitor electrode.

Diversity Analysis of Diazotrophic Bacteria Associated with the Roots of Tea (Camellia sinensis (L.) O. Kuntze)

  • Arvind, Gulati;Sood, Swati;Rahi, Praveen;Thakur, Rishu;Chauhan, Sunita;Nee Chadha, Isha Chawla
    • Journal of Microbiology and Biotechnology
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    • v.21 no.6
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    • pp.545-555
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    • 2011
  • The diversity elucidation by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of 96 associative diazotrophs, isolated from the feeder roots of tea on enriched nitrogen-free semisolid media, revealed the predominance of Gram-positive over Gram-negative bacteria within the Kangra valley in Himachal Pradesh, India. The Gram-positive bacteria observed belong to two taxonomic groupings; Firmicutes, including the genera Bacillus and Paenibacillus; and Actinobacteria, represented by the genus Microbacterium. The Gram-negative bacteria included ${\alpha}$-Proteobacteria genera Brevundimonas, Rhizobium, and Mesorhizobium; ${\gamma}$-Proteobacteria genera Pseudomonas and Stenotrophomonas; and ${\beta}$-Proteobacteria genera Azospira, Burkholderia, Delftia, Herbaspirillum and Ralstonia. The low level of similarity of two isolates, with the type strains Paenibacillus xinjiangensis and Mesorhizobium albiziae, suggests the possibility of raising species novum. The bacterial strains of different phylogenetic groups exhibited distinct carbon-source utilization patterns and fatty acid methyl ester profiles. The strains differed in their nitrogenase activities with relatively high activity seen in the Gramnegative strains exhibiting the highest similarity to Azospira oryzae, Delftia lacustris and Herbaspirillum huttiense.

Scientists' Information Behavior for Bridging the Gaps Encountered in the Process of the Scientific Research Lifecycle (과학기술분야 연구활동 단계별 문제상황 극복을 위한 정보행동 연구)

  • Lee, Jung-Yeoun;Chung, Eun-Kyung;Kwon, Na-Hyun
    • Journal of the Korean Society for information Management
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    • v.29 no.3
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    • pp.99-122
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    • 2012
  • This study analyzed scientists information behaviors when they engage in solving specific research problems in various situations throughout the entire scientific R&D lifecycle process. In-depth interviews with a total of 24 scientists were conducted in their research laboratories, the scientists' everyday workplace and the contexts of scientific research. The theoretical and methodological frameworks employed for this study were Dervin's Sense-making, Savolainen's Everyday Life Information Seeking, and Engestrom's Activity Theory. The findings of this study informed context-specific research and information behaviors of the scientists in the 14 sub stages of the five-stage of R&D lifecycle. Specifically, the study revealed the research objectives and related information behaviors (e.g., information needs, information seeking, information sources and channels, information barriers, etc.) to achieve the objectives at each sub-stage. The study results provided essential information to re-design the information services and strategies that accommodate the scientific R&D lifecycle.

Field measurement and numerical simulation of excavation damaged zone in a 2000 m-deep cavern

  • Zhang, Yuting;Ding, Xiuli;Huang, Shuling;Qin, Yang;Li, Peng;Li, Yujie
    • Geomechanics and Engineering
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    • v.16 no.4
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    • pp.399-413
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    • 2018
  • This paper addresses the issue of field measurement of excavation damage zone (EDZ) and its numerical simulation method considering both excavation unloading and blasting load effects. Firstly, a 2000 m-deep rock cavern in China is focused. A detailed analysis is conducted on the field measurement data regarding the mechanical response of rock masses subjected to excavation and blasting operation. The extent of EDZ is revealed 3.6 m-4.0 m, accounting for 28.6% of the cavern span, so it is significantly larger than rock caverns at conventional overburden depth. The rock mass mechanical response subjected to excavation and blasting is time-independent. Afterwards, based on findings of the field measurement data, a numerical evaluation method for EDZ determination considering both excavation unloading and blasting load effects is presented. The basic idea and general procedures are illustrated. It features a calibration operation of damage constant, which is defined in an elasto-plastic damage constitutive model, and a regression process of blasting load using field blasting vibration monitoring data. The numerical simulation results are basically consistent with the field measurement results. Further, some issues regarding the blasting loads, applicability of proposed numerical method, and some other factors are discussed. In conclusion, the field measurement data collected from the 2000 m-deep rock cavern and the corresponding findings will broaden the understanding of tunnel behavior subjected to excavation and blasting at great depth. Meanwhile, the presented numerical simulation method for EDZ determination considering both excavation unloading and blasting load effects can be used to evaluate rock caverns with similar characteristics.

Model test and numerical simulation on the bearing mechanism of tunnel-type anchorage

  • Li, Yujie;Luo, Rong;Zhang, Qihua;Xiao, Guoqiang;Zhou, Liming;Zhang, Yuting
    • Geomechanics and Engineering
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    • v.12 no.1
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    • pp.139-160
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    • 2017
  • The bearing mechanism of tunnel-type anchorage (TTA) for suspension bridges is studied. Model tests are conducted using different shapes of plug bodies, which are circular column shape and circular truncated cone shape. The results show that the plug body of the latter shape possesses much larger bearing capacity, namely 4.48 times at elastic deformation stage and 4.54 times at failure stage compared to the former shape. Numerical simulation is then conducted to understand the mechanical and structural responses of plug body and surrounding rock mass. The mechanical parameters of the surrounding rock mass are firstly back-analyzed based on the monitoring data. The calculation laws of deformation and equivalent plastic strain show that the numerical simulation results are rational and provide subsequent mechanism analysis with an established basis. Afterwards, the bearing mechanism of TTA is studied. It is concluded that the plug body of circular truncated cone shape is able to take advantage of the material strength of the surrounding rock mass, which greatly enhances its bearing capacity. The ultimate bearing capacity of TTA, therefore, is concluded to be determined by the material strength of surrounding rock mass. Finally, recommendations for TTA design are proposed and discussed.

The Effect of Scientific Discussion Classes Focusing Problem Finding on the Primary School Students' Scientific Creative Problem Solving Ability and Science Process Skills (문제발견 중심의 과학토론수업이 초등학생들의 과학 창의적 문제해결력과 과학탐구능력에 미치는 영향)

  • Kim, Soon-Shik;Lee, Yong-Seob
    • Journal of the Korean Society of Earth Science Education
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    • v.7 no.1
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    • pp.133-143
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    • 2014
  • The purpose of this study was to examine the effect of scientific discussion classes focusing problem finding on the primary school students' scientific creative problem solving ability, science process skills and attitude toward science class. To verify this research problem, the subject of this study was fifth-grade students selected from four classes of M elementary school located in Busan city. For four months, the experimental group of 51 students was taught using the "scientific discussion classes focusing problem finding". The control group also of 53 students was taught in normal classes which used a text-book. All students were given pre and post test to verify the effects of scientific discussion classes focusing problem finding on the primary school students' scientific creative problem solving ability, science process skills and attitude toward science class. The results from this study are as the following. First, the scientific discussion classes focusing problem finding were effective in scientific creative problem solving ability among the primary school students. It is possibly because in the process where one student compare his/her own thoughts with the others' ones and discuss them. Second, the scientific discussion classes focusing problem finding were effective in science process skills among the primary school students. Third, the scientific discussion classes focusing problem finding were effective in attitude toward science class. In conclusion, the scientific discussion classes focusing problem finding had positive effects on improvement of primary school students' scientific creative problem solving ability, science process skills and also could lead to a change in students' cognition about science class to a positive way. Therefore, the scientific discussion class focusing problem finding is hopefully to be provided as an effective instructive strategy of science class in school in the future.

Invasion potential of Kappaphycus alvarezii on corals at Kurusadai Island, Gulf of Mannar, India

  • Mandal, Subir Kumar;Mantri, Vaibhav A.;Haldar, Soumya;Eswaran, Karuppanan;Ganesan, Meenakshisundaram
    • ALGAE
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    • v.25 no.4
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    • pp.205-216
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    • 2010
  • The marine red alga Kappaphycus alvarezii is a major source of $\kappa$-carrageenan. It has been introduced in 20 countries including India. Recently, several reports have expressed concerns about Kappaphycus invasion on Acropora corals at Kurusadai Island in the Gulf of Mannar, India, which is part of a marine bioreserve. To understand the extent of the Kappaphycus invasion, 27 randomly selected locations around Kurusadai Island and the mainland coast were surveyed during May-August 2008 and July 2009. Our rigorous sampling revealed that K. alvarezii was confined to two different patches of 105 m $\times$ 55 m and 8 m $\times$ 9 m located at the southeastern part of Kurusadai Island. The actual extent of the K. alvarezii canopy coverage was 76.7 $m^2$, accounting for less than 0.0035% of the total coral reef area. The daily growth rate of the K. alvarezii at Kurusadai was 0.7%. K. alvarezii was not observed in the coral reef area of the adjoining Pullivasal and Poomarichan Islands or the Palk Bay area cultivation sites. The lack of functional reproductive cycle, low spore viability, and the absence of microscopic phases in the life cycle of this alga coupled with the abundance presence of herbivores may restrict the further spread of this alga, so its invasive potential at Kurusadai Island is considered remote.

Self Charging Sulfanilic Acid Azocromotrop/Reduced Graphene Oxide Decorated Nickel Oxide/Iron Oxide Solar Supercapacitor for Energy Storage Application

  • Saha, Sanjit;Jana, Milan;Samanta, Pranab;Murmu, Naresh Chandra;Lee, Joong Hee;Kuila, Tapas
    • Composites Research
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    • v.29 no.4
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    • pp.179-185
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    • 2016
  • A self-charging supercapacitor is constructed through simple integration of the energy storage and photo exited materials at the photo electrode. The large band gap of $NiO/Fe_3O_4$ heterostructure generates photo electron at the photo electrode and store the charges through redox mechanism at the counter electrode. Sulfanilic acid azocromotrop/reduced graphene oxide layer at the photo electrode trapped the photo generated hole and store the charge by forming double layer. The solar supercapacitor device is charged within 400 s up to 0.5 V and exhibited a high specific capacitance of ~908 F/g against 1.5 A/g load. The solar illuminated supercapacitor shows a high energy and power density of 33.4 Wh/kg and 385 W/kg along with a very low relaxation time of ~15 ms ensuring the utility of the self charging device in the various field of energy storage and optoelectronic application.

Bioprocess Development for Production of Alkaline Protease by Bacillus pseudofirmus Mn6 Through Statistical Experimental Designs

  • Abdel-Fattah, Y.R.;El-Enshasy, H.A.;Soliman, N.A.;El-Gendi, H.
    • Journal of Microbiology and Biotechnology
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    • v.19 no.4
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    • pp.378-386
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    • 2009
  • A sequential optimization strategy, based on statistical experimental designs, is employed to enhance the production of alkaline protease by a Bacillus pseudofirmus local isolate. To screen the bioprocess parameters significantly influencing the alkaline protease activity, a 2-level Plackett-Burman design was applied. Among 15 variables tested, the pH, peptone, and incubation time were selected based on their high positive significant effect on the protease activity. A near-optimum medium formulation was then obtained that increased the protease yield by more than 5-fold. Thereafter, the response surface methodology(RSM) was adopted to acquire the best process conditions among the selected variables, where a 3-level Box-Behnken design was utilized to create a polynomial quadratic model correlating the relationship between the three variables and the protease activity. The optimal combination of the major medium constituents for alkaline protease production, evaluated using the nonlinear optimization algorithm of EXCEL-Solver, was as follows: pH of 9.5, 2% peptone, and incubation time of 60 h. The predicted optimum alkaline protease activity was 3,213 U/ml/min, which was 6.4 times the activity with the basal medium.