Clear Experimental Signature of Charge-Orbital density wave in Nd1−x_{1-x}Ca1+x_{1+x}MnO4_{4}

Single Crystals of Nd$_{1-x}$Ca$_{1+x}$MnO$_{4}$ have been prepared by the travelling floating-zone method, and possible evidence of a charge -orbital density wave in this material presented earlier [PRB68,092405 (2003)] using High Resolution Electron Microscopy [HRTEM] and Electron Diffraction [ED]. In the current note we present direct evidence of charge-orbital ordering in this material using heat capacity measurements. Our heat capacity measurements indicate a clear transition consistent with prior observation. We find two main transitions, one at temperature $T_{_H}=310-314$ K, and other at $T_{_A}=143$ K. In addition, we may also conclude that there is a strong electron-phonon coupling in this material.Comment: 7 pages, 8 figure

On entropy, specific heat, susceptibility and Rushbrooke inequality in percolation

We investigate percolation, a probabilistic model for continuous phase transition (CPT), on square and weighted planar stochastic lattices. In its thermal counterpart, entropy is minimally low where order parameter (OP) is maximally high and vice versa. Besides, specific heat, OP and susceptibility exhibit power-law when approaching the critical point and the corresponding critical exponents $\alpha, \beta, \gamma$ respectably obey the Rushbrooke inequality (RI) $\alpha+2\beta+\gamma\geq 2$. Their analogues in percolation, however, remain elusive. We define entropy, specific heat and redefine susceptibility for percolation and show that they behave exactly in the same way as their thermal counterpart. We also show that RI holds for both the lattices albeit they belong to different universality classes.Comment: 5 pages, 3 captioned figures, to appear as a Rapid Communication in Physical Review E, 201

Phase-coexisting patterns, horizontal segregation and controlled convection in vertically vibrated binary granular mixtures

We report new patterns, consisting of coexistence of sub-harmonic/harmonic and asynchronous states [for example, a granular gas co-existing with (i) bouncing bed, (ii) undulatory subharmonic waves and (iii) Leidenfrost-like state], in experiments on vertically vibrated binary granular mixtures in a Heleshaw-type cell. Most experiments have been carried out with equimolar binary mixtures of glass and steel balls of same diameter by varying the total layer-height ($F$) for a range of shaking acceleration ($\Gamma$). All patterns as well as the related phase-diagram in the ($\Gamma, F$)-plane have been reproduced via molecular dynamics simulations of the same system. The segregation of heavier and lighter particles along the horizontal direction is shown to be the progenitor of such phase-coexisting patterns as confirmed in both experiment and simulation. At strong shaking we uncover a {\it partial} convection state in which a pair of convection rolls is found to coexist with a Leidenfrost-like state. The crucial role of the relative number density of two species on controlling the buoyancy-driven granular convection is demonstrated. A possible model for spontaneous horizontal segregation is suggested based on anisotropic diffusion

Quenching of light hadrons at RHIC in a collisional energy loss scenario

We evaluate the nuclear suppression factor, $R_{AA}(p_T)$ for light hadrons by taking into account the collisional energy loss. We show that in the measured $p_T$ domain of RHIC the elastic process is the dominant mechanism for the partonic energy loss.Comment: 4 pages with 3 figures, Quark Matter 2008 Proceeding

The impact of support for imports on food security in Indonesia

This study on the impact of import support on food security was conducted in eight developing countries -including Indonesia- that were facing food insecurity and were recipients of subsidized exports and food aid. In Indonesia, the analysis of import flows in comparison with overall production and consumption data led to the selection of the three import substitute commodities, soybean, sugar and milk, that were the focus of this study. The objective of the study was to provide an analysis of the national impact of export support measures on food security, by taking into account their impact on the producers and consumers of the three commodities.IMPORTS, EXPORTS, FOOD, ECURITY, SOYBEANS, SUGAR, MILK, FOOD AID, Agricultural and Food Policy, Crop Production/Industries, Food Security and Poverty, International Relations/Trade, Production Economics,

Weak Kaon Production off the Nucleon

The weak kaon production off the nucleon induced by neutrinos is studied at the low and intermediate energies of interest for some ongoing and future neutrino oscillation experiments. This process is also potentially important for the analysis of proton decay experiments. We develop a microscopical model based on the SU(3) chiral Lagrangians. The basic parameters of the model are fpi, the pion decay constant, Cabibbo's angle, the proton and neutron magnetic moments and the axial vector coupling constants for the baryons octet, D and F, that are obtained from the analysis of the semileptonic decays of neutron and hyperons. The studied mechanisms are the main source of kaon production for neutrino energies up to 1.2 to 1.5 GeV for the various channels and the cross sections are large enough to be amenable to be measured by experiments such as Minerva and T2K

Low Mass Dilepton Rate from the Deconfined Phase

We discuss low mass dilepton rates ($\le 1$ GeV) from the deconfined phase of QCD using both perturbative and non-perturbative models and compare with those from lattice gauge theory and in-medium hadron gas. Our analysis suggests that the rate at very low invariant mass ($M\le 200$ MeV) using the nonperturbative gluon condensate in a semiempirical way within the Green function dominates over the Born-rate and independent of any uncertainty associated with the choice of the strong coupling in perturbation theory. On the other hand the rate from $\rho-q$ interaction in the deconfined phase is important between 200 MeV $\le M \le 1 GeV as it is almost of same order of the Born-rate as well as in-medium hadron gas rate. Also the higher order perturbative rate, leaving aside its various uncertainties, from HTL approximation becomes reliable at$M\ge 200$MeV and also becomes comparable with the Born-rate and the lattice-rate for$M\ge 500$ MeV, constraining on the broad resonance structures in the dilepton rate at large invariant mass. We also discuss the lattice constraints on the low mass dilepton rate. Furthermore, we discuss a more realistic way to advocate the quark-hadron duality hypothesis based on the dilepton rates from QGP and hadron gas than it is done in the literature.Comment: 24 pages, 9 figures; Discussion added, Accepted in Phys. Rev.

Perancangan Antena Mikrostrip Array 2x2 Frekuensi 2,4 Ghz Untuk Komunikasi Iot

Jurnal ini ditujukan untuk men-desain antena mikrostrip dengan empat elemen peradiasi dengan susunan array 2x2 yang bekerja pada frekuensi 2,4 Ghz . Teknik pencatuan yang digunakan pada perancangan antena microstrip adalah teknik pencatuan saluran microstrip. Pada desain antena ini dititik beratkan pada gain dengan frekuensi 2,4 Ghz yang digunakan untuk komunikasi antara sensor-sensor pada jaringan Wi-Fi dengan sensor gateway. Hasil simulasi perancangan antena pada frekuensi 2.4 Ghz didapatkan return loss sebesar -27.23 dB dengan VSWR sebesar 1.089. Bandwidth yang didapatkan pada perancangan antena mikrostrip array 2x2 adalah 308 MHz

Rancang Bangun Antenna Mikrostrip Peripheral Slits Linear Array Untuk Aplikasi Wi-Fi

Wireless Fidelity (Wi-Fi) is the modern telecommunication technology nowadays being so widely used and developed at operating frequency of 2.4 GHz, that needs microstrip antenna as best suited supporting means for transmitting and receiving data signals as well at its wave transceiver subsystem. The proposed antenna design were consists of four elements rectangular patch antenna with peripheral slits technique arranged in a linear array of 2x2 operating at the frequency of 2.4 GHz until 2.5 GHz. In addition to that, the feeding technique used in this research is microstrip fed line. The simulation from this research resulted in reducing the size of related antenna dimension up to 17% compared to that of four elements array without peripheral slits. It is also apparent that the bandwidth of the proposed antenna is 320 MHz (2.253 GHz–2.573 GHz) which is equivalent to bandwidth increase percentage of 13.07%, The simulation results in the center of frequency 2.448 GHz obtained return loss of -26.14 dB with a VSWR of 1.104. The measurement results obtained bandwidth of the proposed antenna is 150 MHz (2.424 GHz–2.574 GHz) which is equivalent to 12% increase of bandwidth percentage. The results of measurements process at the center of frequency 2.448 GHz obtained value of return loss of -16.88 dB with VSWR of 1.304