Identifikasi Miskonsepsi Materi Kesetimbangan Kimia Menggunakan Tes Diagnostik Pilihan Ganda Tiga Tingkat (Three-tier Multiple Choice) Pada Peserta Didik Kelas XI Mia SMA Negeri 2 Pekanbaru

The aim of this research were to know misconceptions and the category level of misconceptions in the second year students of SMA Negeri 2 Pekanbaru aboutt concepts of chemical equallibrium. This research took place in SMA Negeri 2 Pekanbaru and the data were collected on April 2017. was all the students of XI MIA class of four classes. The population consisted of 161 students. The sample was all the population. This research was descriptive quantitative. The technique of collecting data used diagnostic test and interview. The result showed that students found misconception in the definition concept of chemical equallibrium with the percentage was 34,78% (category of average), for the concept of heterogen and homogen was 36,335% (average), the concept of dissociation degree was 33,54% (average), the concept of Kc measurement was 43,785% (average), the concept of Kp measurement was 27,55% (poor), the principle concept of Le Chatelier was 36,764% (average), the concept of using chemical equallibrium in world industry was 23,60% (poor)

Pemetaan Sebaran Ikan Tongkol (Euthynnus SP.) Dengan Data Klorofil-α Citra Modis Pada Alat Tangkap Payang (Danish-seine) Di Perairan Teluk Palabuhanratu, Sukabumi, Jawa Barat

Palabuhanratu waters is the center of important economic fisheries commodity like tinker mackerel (Euthynnus sp.). Statistic datas of PPNP (2011) showed that production value of fishery in Palabuhanratu was decreased 3% from a year before, that is have an impact to economy condition of Palabuhanratu. Payang (Danish-seine) as a one of pelagic fishing gear in Palabuhanratu have an imbalance condition between supplies and income. Tinker mackerel production decreased in 2011 resulted in the economic condition of fishermen Palabuhanratu decreased. As one of the predictors of the presence of fish, chlorophyll-a can be used in the determination of the study the fishing ground through remote sensing technology. The purpose of the studies are to analyze the factors that influence the distribution of tinker mackerel (Euthynnus sp.), analyze the relation of chlorophyll-a and the value of the catch, and create a map of potential Palabuhanratu tinker mackerel in the Palabuhanratu waters. The research method used was descriptive with the case study and data collection by purposive sampling. Chlorophyll-a values in March - April 2012 ranged from 0,70 mg / l – 2,585 mg / l, with an average value of 0,475 mg / l. The amount of catches reach 695 kg in March and April of 426,24 kg. The results of measurements of field data has showed that average of salinity, SPL, DO, current, and depth respectively: 33 ppt, 30,9° C, 6,28 mg / l, 0,108 m / s, and 288,67 m. The results of the regression test showed that current was the significant variable with a value of p=0,02 (p <0,05) and r = 0.690 (indicating a strong correlation). The results showed that correlation pattern between water quality parameters, chlorophyll-a, and the catch of mackerels (Euthynnus sp.). Based on field data and MODIS image overlay, potential fishing areas in March - April 2012 include: Cimandiri, Tanjung Kembar, Gedogan, Ujung Karangbentang, Ujung Sodongprapat, and the Gulf Amuran

Control-volume representation of molecular dynamics

A Molecular Dynamics (MD) parallel to the Control Volume (CV) formulation of fluid mechanics is developed by integrating the formulas of Irving and Kirkwood, J. Chem. Phys. 18, 817 (1950) over a finite cubic volume of molecular dimensions. The Lagrangian molecular system is expressed in terms of an Eulerian CV, which yields an equivalent to Reynolds' Transport Theorem for the discrete system. This approach casts the dynamics of the molecular system into a form that can be readily compared to the continuum equations. The MD equations of motion are reinterpreted in terms of a Lagrangian-to-Control-Volume (\CV) conversion function $\vartheta_{i}$, for each molecule $i$. The \CV function and its spatial derivatives are used to express fluxes and relevant forces across the control surfaces. The relationship between the local pressures computed using the Volume Average (VA, Lutsko, J. Appl. Phys 64, 1152 (1988)) techniques and the Method of Planes (MOP, Todd et al, Phys. Rev. E 52, 1627 (1995)) emerges naturally from the treatment. Numerical experiments using the MD CV method are reported for equilibrium and non-equilibrium (start-up Couette flow) model liquids, which demonstrate the advantages of the formulation. The CV formulation of the MD is shown to be exactly conservative, and is therefore ideally suited to obtain macroscopic properties from a discrete system.Comment: 19 pages, 15 figure

Polarized Redundant-Baseline Calibration for 21 cm Cosmology Without Adding Spectral Structure

21 cm cosmology is a promising new probe of the evolution of visible matter in our universe, especially during the poorly-constrained Cosmic Dawn and Epoch of Reionization. However, in order to separate the 21 cm signal from bright astrophysical foregrounds, we need an exquisite understanding of our telescopes so as to avoid adding spectral structure to spectrally-smooth foregrounds. One powerful calibration method relies on repeated simultaneous measurements of the same interferometric baseline to solve for the sky signal and for instrumental parameters simultaneously. However, certain degrees of freedom are not constrained by asserting internal consistency between redundant measurements. In this paper, we review the origin of these "degeneracies" of redundant-baseline calibration and demonstrate how they can source unwanted spectral structure in our measurement and show how to eliminate that additional, artificial structure. We also generalize redundant calibration to dual-polarization instruments, derive the degeneracy structure, and explore the unique challenges to calibration and preserving spectral smoothness presented by a polarized measurement.Comment: 12 pages, 3 figures, updated to match the published MNRAS versio

Imaging on PAPER: Centaurus A at 148 MHz

We present observations taken with the Precision Array for Probing the Epoch of Reionization (PAPER) of the Centaurus A field in the frequency range 114 to 188 MHz. The resulting image has a 25' resolution, a dynamic range of 3500 and an r.m.s. of 0.5 Jy\beam (for a beam size of 25' x 23'). A spectral index map of Cen A is produced across the full band. The spectral index distribution is qualitatively consistent with electron reacceleration in regions of excess turbulence in the radio lobes, as previously identified morphologically. Hence, there appears to be an association of 'severe weather' in radio lobes with energy input into the relativistic electron population. We compare the PAPER large scale radio image with the X-ray image from the ROSAT All Sky Survey. There is a tentative correlation between radio and X-ray features at the end of the southern lobe, some 200 kpc from the nucleus, as might be expected from inverse Compton scattering of the CMB by the relativistic electrons also responsible for the radio synchrotron emission. The magnetic fields derived from the (possible) IC and radio emission are of similar magnitude to fields derived under the minimum pressure assumptions, ~ 1 {\mu}G. However, the X-ray field is complex, with large scale gradients and features possibly unrelated to Cen A. If these X-ray features are unrelated to Cen A, then these fields are lower limits.Comment: 9 pages, 5 figures; Section 7 and Fig. 5 have been revised and minor corrections have been implemented throught the paper; submitted for publication to MNRA