GSTF Digital Library (GSTF-DL): Open Journal Systems (Global Science and Technology Forum)
Not a member yet
1700 research outputs found
Sort by
Base-catalyzed Asymmetric Diels-Alder Reaction of N-Nosyl-3-hydroxy-2-pyridone with a Chiral Acrylate, and Its Application to the Synthesis of Aminocarbasugars
No full textA base-catalyzed asymmetric Diels-Alderreaction of N-sulfonylated 3-hydroxy-2-pyridone and achiral acrylate has been developed. In the presence of acatalytic amount of cinchona alkaloid, the reactionproceeded smoothly in aqueous tetrahydrofuran and gave ahighly functionalized bicyclolactam in good yield with up to91% diastereoselectivity (de). Absolute configuration of theadduct was established as 1R, 4S, 8R, based ontransformation to compounds with known configuration. Itssynthetic utility was demonstrated by preparing 2-epivalidamine, 2,3-epivalidamine, and an enantiomer of aTamiflu intermediate, in short steps
Synthesis, Characterization and Biological Activity of Organotin(IV) Complexes featuring di-2-ethylhexyldithiocarbamate and N-methylbutyldithiocarbamate as Ligands
No full textOrganotin(IV) compounds have received tremendous attention for their synthesis, characterization and biological activities and their ability to bind with sulfur ligand such as dithiocarbamate ligand. Organotin(IV) dithiocarbamate complexes can be synthesized by the reaction of carbon disulphide with secondary amine. Four new organotin(IV) dithiocarbamate complexes were successfully synthesized by the reactions between di-2-ethylhexyldithiocarbamate, C16H34NCS2 and N-methylbutyldithiocarbamate, C5H12NCS2 with dibutyltin(IV) dichloride and triphenyltin(IV) chloride, RxSnClx (R = Bu, Ph) and (x = 1, 2 or 3). These series of complexes were synthesized using “in situ†insertion method and characterized by determination of melting point, CHNS elemental analysis, infrared spectroscopy (FT-IR) and UV-vis spectroscopy. The melting points of the synthesized compounds were in the range 88.3 - 128.4 °C. The experimental CHNS data of the compounds, mostly exhibit the calculated CHNS values. Using infrared spectra (FT-IR), the formation of organotin(IV) dithiocarbamate complexes were confirmed by the presence of v(C=N+) at 1464 - 1497 cm-1, v(C-S) at 963 - 1025 cm-1 and v(Sn-S) at 412 - 445 cm-1 in all complexes. Besides that, the UV-vis analysis showed the peaks chromophore of N=C within range 259 - 260 nm, nonbonding electron on sulphur and charges transferred between the tin metal and ligand (M-L). Using TGA analysis, complex 1 and 3 show two degradation curve but complex 2 and 4 shows only one degradation curves. The antibacterial activity of all synthesized organotin(IV) dithiocarbamate complexes were then determined towards four types of bacterial strains which were Escherichia coli, Staphylococcus aureus, Salmonella thypi and Bacillus cereus. Penicillin was used as positive control and streptomycin as negative control in order to compare diameter of inhibition zone between both controls and complexes. From antibacterial test, almost all synthesized complexes were found to give positive results. Thus, it can be concluded that the complexes formed do have applications in biological and medical aspects
Enhancing Creativity in Chinese Classrooms Module and Techniques
No full textthe paper addresses the need for a creativity curriculum in Chinese education provides a creativity development module designed to work effectively in the Chinese culture and educational environment. Drawing on an extensive cross-domain literature review of creativity research, the project concludes that individual creativity is best promoted through an interdisciplinary, self-reflective and holistic approach. Based on this research, a flexible creativity module is designed that creates a framework which can be used across disciplines to improve individual creativity in a diverse and complex environment like Chinese society
Effects of Fly Ash, Silica Fume, and Ground-Granulated Blast Slag on Properties of Self-Compacting High Strength Lightweight Concrete
No full textIn this paper, the effect of utilizing Fly ash (FA), Silica fume (SF), Ground granulated blast slag (GGBS), and various combinations of them is assessed. Their effect on the fresh stage and mechanical properties of Self-compacting Lightweight Concrete (SCCLWC) is investigated and compared to a control mix without Supplementary Cementitious Materials (SCMs). Flowability, compressive strength, and flexural strength were the main criteria considered in the evaluation. Moreover, the applicability of the ACI 318 reduction factor (λ) for flexural strength was assessed for all mixes to capture the effect of various SCMs based on the lower and upper limits of the proposed ACI 318 equation. Results from the evaluation show that SF greatly improved the compressive strength and GGBS increased flexural strength of SCCLWC. However, SF reduces the flowability of SCCLWC. Equally important, FA achieved the lowest increase in compressive strength compared to the control mix. Furthermore, the λ value of 0.85 proposed by ACI 318 for sand-lightweight provides a good estimate of LWC properties even when different SCMs are utilized. However, fly ash can affect the λ value at early age
Concrete with Recycled Aggregate: Evaluation of Mechanical Properties
No full textThis paper discusses the suitability of producing concrete with 100% recycled aggregate to meet durability and strength requirements for different applications. Aggregate strength, gradation, absorption, specific gravity, shape, and texture are some of the physical and mechanical characteristics that contribute to the strength and durability of concrete. In general, quality of the recycled aggregate depends on the loading and environmental conditions that the demolished structures were exposed to. Therefore, the experimental program consisted of two tasks. The first task was focused on the evaluation of physical and mechanical properties of the recycled aggregate over 6 months to determine variability in aggregate properties. The second task was directed towards evaluation of concrete portieres produced with fine and coarse recycled aggregate. Several concrete mixes were prepared with combinations of different aggregate grades and the results were compared to that of a control mix. Workability and compressive strength were performed to assess the suitability of these mixes for different applications
Indication Strike Slip Movement a Part of Sorong Fault Zone in Yapen Island, Papua, Indonesia
Get PDFSorong Fault Zone is located at northern of the Papua Island. It is moving from the body bird of Papua Island toward south-southeast of Molluca Island, spreading to east part of Celebes Island, and overstepping east part of Yapen Island which occupied the Bird’s Neck of Papua. The fault became a border between Caroline oceanic plate (part of pacific oceanic plate) and Australian continental plate. Instead, The Sorong Fault Zone controlled forming of Salawati Basin in west of Yapen Island. The Sorong Fault, Lengguru Fold thrust belt, Tarera-Aiduna Fault, and Seram Thrust are structural features which associated with the collision between the Australian continental plate and the Pacific oceanic plate at Oligo-Miocene as regional uplift.This paper explains the indication trace of Sorong Fault Zone in research area, there are shear zone, minor fault, brecciation zone, and lineament in Cataclastic Breccia Formation. The research was conducted in the Sumberbaba area, Yapen Timur sub-district, Yapen Waropen district with fieldwork as the main method. The Sumberbaba area is located appropriate in fault line of Sorong Fault Zone. The general structure pattern that worked in research area is northwest-southeast direction with strike-slip movement. The lithologies at the area are Cataclastic Breccia in late Miocene, tuffaceous sandstone and tuffaceous breccias for Volcanic Yapen Formation in late Eocene to early Miocene, limestone for Wurui Formation in early Miocene, and sandstone Kurudu Formation in early Pliocene.Structural analysis in this area was done by using the measurement method of collecting structure evidence. There are shear fracture and extension fracture in rock outcrop. The characteristics of fault should have shear orientation or strike of shear plane, dip direction, and slickenside. The majority of lineaments are in NW-SE direction, lineament orientation at the fault in research area in NW-SE (almost W-E) and it is appropriately following the Sorong Fault Zone
Crissot and his ‘Alang Dios’: A Metacritical Study
No full textInformed by John Guillory’s theory on canon-formation, and Michel Foucault’s author-function, this present work critically analyzes the criticisms about Juan Crisostomo Soto and his masterpiece Alang Dios! It intends to disclose and interrogate the power relations/struggle at work in the creation of a “Crissot†that was over and beyond the historical man that he was—a construct, a revered author, a literary icon, a “myth†of Kapampangan Literature. Significantly, it offers critical foundation and framework in the study of regional literature which is the pressing need at the moment to help characterize national literary sensibility. Using close reading and metacriticism to unveil the assumptions, norms, and contexts that necessitated the criticisms, findings show that the critics were moved by the needs of their own time and space. This means that their criticisms were meant to satisfy the demands of time that led to the use of similar means of propagating such demands through the use of press, newspapers, agencies, relevant situations, and celebrations that led to the sense of identity and valor for every Kapampangan and Kapampangan literature as a whole amidst colonial influences, subjugations, and promising literature across regions
Factors Influencing the Career Choice of Nursing Students
Get PDFThe people who choose nursing as a career should choose it consciously, should very well recognize it, and embrace it, and love it so that, this profession can develop and rise in social status. This was a descriptive type of study, aimed to determine the reasons why the students choose to study nursing
Male and Societal Responses to Vasectomy in Java, Indonesia
Get PDFBackground: Indonesia is the fourth most populous nation, with a growth rate of 1.49 percent per year. Such a great number of people with lack of sufficient knowledge and skills are a challenge when it comes to issues related to national development. Generally, the result of the Family Planning Program (FPP) to Indonesian women has met much success, where approximately 60 percent of all participants are women. Fear and anxiety rank as major reasons why men remain somewhat hesitant to participate in the surgical method of vasectomy. There are also misled perceptions that sometimes cause husbands to hesitate and decided not to have a vasectomy. This often occurs because of the lack of general information and knowledge about a vasectomy and all of its effects to their long-term physical and psychological and social side effects of Javanese men.Research Objective: To explore Javanese men’s response after undergoing a vasectomy as well as society’s perspectives about the procedures.Research Method: This is a qualitative research study applying a grounded theory approach. The sample was selected using a theoretical sampling technique. The data collection instruments used include field reports, audio recordings, video recordings, and field notes. The data was analyzed using Colaizzi`s method.Research Results: Seven individuals participated in this study. The reasons participants decided to have a vasectomy were due to their social responsibility, feeling pity for their wife, and concern for the welfare of their children in the future. There was no general changes noticed in the physical nature of participants. Sexual ability after the vasectomy surgery showed no changes. Social views toward the vasectomy surgical varied. Most within Javanese society believe that having children is important, and that the welfare of the family is also important.Conclusion: Participants felt no significant physical changes after the vasectomy was completed. They decide to have a vasectomy to show their affection towards their wife, the responsibility towards the family and children welfare in the future. Therefore, undergoing a vasectomy in Java, Indonesia can improve the quality of the marital relationship
Influencing Leadership and Building Research Capacity through the Implementation of Health Policy into Practice
Get PDFLeadership in nursing and midwifery is a cornerstone to guide and support teams in the dynamic and rapidly changing health environment. Developing research capacity in health is also a key factor to produce and implement a sound evidence base for practice. Internationally, building health service research capacity is a recognized essential factor to influence and inform policy and practice. This includes developing research capacity across the range of individuals and teams, organisations and networks. This paper describes how one NHS Health Board in Scotland promoted a supportive environment and activities to develop leadership and increase research capacity to support implementation of national Early Years policies into practice