Indonesian Institute of Sciences

About: Indonesian Institute of Sciences is a facility organization based out in Jakarta, Indonesia. It is known for research contribution in the topics: Population & Biology. The organization has 4795 authors who have published 10544 publications receiving 76990 citations. The organization is also known as: Indonesian Institute of Sciences Cibinong, Indonesia.

Development of reduced graphene oxide from biowaste as an electrode material for vanadium redox flow battery

Abstract: Vanadium redox flow battery (VRB) is a renowned electrochemical energy storage device for large scale applications owing to its promising storage capability, long life and safety. However, the lower efficiency of VRB system combined with the non-renewable graphite-based electrodes have limited the widespread of VRB commercial market. This study investigates the feasibility of converting renewable biomass waste, namely spent coffee beans, into reduced graphene oxide (rGO) as an alternate electrode material for VRB system. As prepared rGO has been thoroughly characterised and employed to design a modified electrode for VRB. The electrochemical performance of rGO based modified electrodes has been comprehensively examined using electrochemical impedance spectroscopy, cyclic voltammetry and galvanostatic charge-discharge cycling. The results demonstrate that the energy, voltage and coulombic efficiencies of rGO based electrodes are over 90%, which are comparable to that of commercially used pristine graphite electrode. Moreover, a stable cyclic performance is observed for rGO based electrodes over a total of 65 cycles owing to their high electrocatalytic activity and improved charge transfer. The stable performance and comparable efficiency present promising potential of biomass derived rGO as a low-cost replacement to the commercial graphite as an electrode material for VRB applications.

Molecular evidence suggests radical revision of species limits in the great speciator white-eye genus Zosterops

Abstract: White-eyes (Zosterops spp.) are a group of small passerines distributed across the Eastern Hemisphere that have become a textbook example of rapid speciation. However, traditional taxonomy has relied heavily on conservative plumage features to delimit white-eye species boundaries, resulting in several recent demonstrations of misclassification. Resolution of confused taxonomy is important in order to correctly delimit species and identify taxa which may require conservation, particularly in Asia where the songbird trade is decimating wild populations. In this study, we aim to untangle multiple instances of confused taxonomic treatment in three large, widespread Asian wastebasket species complexes of white-eye (Oriental White-eye Zosterops palpebrosus, Japanese White-eye Zosterops japonicus and Mountain White-eye Zosterops montanus) renowned for their conservative morphology. Using mitochondrial DNA from 173 individuals spanning 42 taxa, we uncovered extensive polyphyly in Z. palpebrosus and Z. japonicus and propose some radically revised species limits under which former members of Z. palpebrosus and Z. japonicus would be reassigned into four and two different species, respectively. The revised taxonomy results in a net loss of two previously recognized species and a net gain of two newly recognized species, leading to significant taxonomic change but a lack of additional species-level diversity. One of the newly elevated species, Zosterops melanurus from Java and Bali, is also the world’s most heavily traded songbird and requires urgent conservation attention.

Insight into particle production mechanisms via angular correlations of identified particles in pp collisions at √s = 7 TeV

Abstract: Two-particle angular correlations were measured in pp collisions at $$\sqrt{s} = 7$$ TeV for pions, kaons, protons, and lambdas, for all particle/anti-particle combinations in the pair. Data for mesons exhibit an expected peak dominated by effects associated with mini-jets and are well reproduced by general purpose Monte Carlo generators. However, for baryon–baryon and anti-baryon–anti-baryon pairs, where both particles have the same baryon number, a near-side anti-correlation structure is observed instead of a peak. This effect is interpreted in the context of baryon production mechanisms in the fragmentation process. It currently presents a challenge to Monte Carlo models and its origin remains an open question.

Grand unified theory based on the SU(6) symmetry

Abstract: We present a complete set of generators for the rank 5 special unitary group, SU(6), to unify strong, weak and electromagnetic interactions. The unification is realized through the breaking pattern of SU(6){yields}SU(3){sub C}xSU(3){sub H}xU(1){sub C} followed by SU(3){sub H}{yields}SU(2){sub L}xU(1){sub B}. All known elementary particles and its quantum numbers are well accommodated in its {l_brace}6{r_brace} and {l_brace}15{r_brace} multiplets. These multiplets require a new neutral fermion which should be assigned as the heavy Majorana neutrino to realize the seesaw mechanism naturally.