Pemanfaatan Bottom Ash Sebagai Agregat Buatan

The aim of this study is to explore the possible use of bottom ash as artificial aggregates. It is found that the pelletizer method by using mixer without blade is one possibility to manufacture artificial aggregates. The optimum mixture composition of artificial aggregate is found to be 3 BA : 1FA : 0,5 C , by weight, and immersed once in cement slurry. The water content in ssd condition is 27% with the compressive strength of the aggregate 2.4 MPa on the seventh day. Concrete produced with mixture compositition of 1 cement : 1.5 sand by weight, resulted in water content of 14.63% in ssd condition and compresive strength of 14.20 MPa at 28th day

Pembuatan Pasta Ringan Geopolimer Celluler Lightweight Concrete (Clc) Berbasis Campuran Lumpur Sidoarjo Dan Fly Ash

Penelitian ini membahas upaya pemanfaatan lumpur Sidoarjo dan sisa pembakaran batubara berupa fly ash agar dapat bermanfaat untuk dunia konstruksi sebagai pengganti semen. Penelitian ini menggunakan bahan dasar lumpur Sidoarjo, fly ash, NaOH, sodium silikat, dan foam agent. Variasi kadar sodium silikat yang digunakan pada percobaan sebesar 30%, 40%, 50% dan 60% dari massa campuran lumpur dan fly ash,dengan memperhatikan perbandingan massa larutan sodium silikat dengan larutan NaOH. Variasi molaritas NaOH yang digunakan pada percobaan sebesar 5M, 6M, 7M dan 8M.Untuk menghasilkan berat jenis yang lebih kecil maka ditambahkan foam agent. Perbandingan volume foam agent dengan air yang digunakan adalah 1:50. Pada masing-masing penelitian tersebut diberikan variasi pemberian foam sebesar 0.5 liter, 1 liter, dan 1.5 liter yang dikonversi menjadi perbandingan massa foam dengan massa binder (campuran lumpur Sidoarjo, fly ash, NaOH padat, sodium silikat dan air). Pengujian yang dilakukan adalah tes kuat tekan pada benda uji berukuran 5×5×5 cm3, dan uji berat jenis.Hasil terbaik dari penelitian ini, yaitu campuran fly ash murni dengan komposisi larutan sodium silikat 480 gram (60%), NaOH 5M, dan penambahan foam 1.5 liter.Hasil kuat tekan umur 7 hari sebesar 1.44 MPa dan berat jenis sebesar 0.61 gr/cm3

Implementasi Peraturan Daerah Kota Pekanbaru No. 8 Tahun 2012 Tentang Retribusi Izin Gangguan ( Studi Kasus SPBU)

Pekanbaru city is one of the cities in Indonesia are experiencing a rapid increase in business development and investment in Indonesia. Disturbance Permit be one important factor in obtaining legality of local authorities towards the establishment of a business. Appropriation nuisance permit (HO) aims to protect the public interest and to maintain order and as a form of government oversight and pengedalian in certain locations which may cause hazards losses and disruption. Establishment of a gas station in the city of Pekanbaru often cause problems with the surrounding community. On the other hand there are many gas station stations that have not paid levies nuisance permit (HO). Integrated Service Agency and Investment (BPTPM) Pekanbaru City as an institution designated by the city of Pekanbaru who has authority in the permitting process and the levy charged for this permit in accordance with Regulation City of Pekanbaru No. 8 in 2012 regarding Disturbance Permit.Based on these findings, this study aims to determine the extent of implementation and the factors that affect the implementation of Pekanbaru City Regional Regulation No. 8 in 2012. This study uses the theory of implementation by Van Meter and Van Horn who has six variables, standards and objectives, resources, characteristics of the implementing agencies, communication between organizations, socio-economic conditions and political and disposition. The method used in this research is qualitative research. With the technique performed is purposive sampling to key informants. In this study, the informant is BPTPM, Disperindag Pekanbaru and related institutions. In gathering the data used qualitative approach with the method of observation and interviews, after the data is collected then analyzed by descriptive.Based on the research that has been carried out based on theoretical concepts, the implementation of Local Regulation No. 8 in 2012 Licenses Disorders at the Gas Stations, has been implemented by BPTPM. However, implementation of the regulations are not well realized. Weak sanctions make local regulation of fee collection process is not going well. The lack of resources in the form of personnel and technical team in the field also affects the implementation of the local regulation

Inhomogeneous Quasi-stationary States in a Mean-field Model with Repulsive Cosine Interactions

The system of N particles moving on a circle and interacting via a global repulsive cosine interaction is well known to display spatially inhomogeneous structures of extraordinary stability starting from certain low energy initial conditions. The object of this paper is to show in a detailed manner how these structures arise and to explain their stability. By a convenient canonical transformation we rewrite the Hamiltonian in such a way that fast and slow variables are singled out and the canonical coordinates of a collective mode are naturally introduced. If, initially, enough energy is put in this mode, its decay can be extremely slow. However, both analytical arguments and numerical simulations suggest that these structures eventually decay to the spatially uniform equilibrium state, although this can happen on impressively long time scales. Finally, we heuristically introduce a one-particle time dependent Hamiltonian that well reproduces most of the observed phenomenology.Comment: to be published in J. Phys.

Statistical model for intermittent plasma edge turbulence

The Probability Distribution Function of plasma density fluctuations at the edge of fusion devices is known to be skewed and strongly non-Gaussian. The causes of this peculiar behaviour are, up to now, largely unexplored. On the other hand, understanding the origin and the properties of edge turbulence is a key issue in magnetic fusion research. In this work we show that a stochastic fragmentation model, already successfully applied to fluid turbulence, is able to predict an asymmetric distribution that closely matches experimental data. The asymmetry is found to be a direct consequence of intermittency. A discussion of our results in terms of recently suggested BHP universal curve [S.T. Bramwell, P.C.W. Holdsworth, J.-F. Pinton, Nature (London) 396, 552 (1998)], that should hold for strongly correlated and critical systems, is also proposedComment: 13 pages. Physica Review E, accepte

The Spectator Electromagnetic Effect on Charged Pion Spectra in Peripheral Ultrarelativistic Heavy-Ion Collisions

We estimate the electromagnetic effect of the spectator charge on the momentum spectra of $\pi^+$ and $\pi^-$ produced in peripheral Pb+Pb collisions at SPS energies. We find that the effect is large and results in strongly varying structures in the $x_F$ dependence of the $\pi^+/\pi^-$ ratio, especially at low transverse momenta where a deep valley in the above ratio is predicted at $x_F \sim$ 0.15 -- 0.20. It appears that the effect depends on initial conditions. Thus, it provides new information on the space and time evolution of the non-perturbative pion creation process.Comment: 20 pages and 8 figure

First and second order clustering transitions for a system with infinite-range attractive interaction

We consider a Hamiltonian system made of $N$ classical particles moving in two dimensions, coupled via an {\it infinite-range interaction} gauged by a parameter $A$. This system shows a low energy phase with most of the particles trapped in a unique cluster. At higher energy it exhibits a transition towards a homogenous phase. For sufficiently strong coupling $A$ an intermediate phase characterized by two clusters appears. Depending on the value of $A$ the observed transitions can be either second or first order in the canonical ensemble. In the latter case microcanonical results differ dramatically from canonical ones. However, a canonical analysis, extended to metastable and unstable states, is able to describe the microcanonical equilibrium phase. In particular, a microcanonical negative specific heat regime is observed in the proximity of the transition whenever it is canonically discontinuous. In this regime, {\it microcanonically stable} states are shown to correspond to {\it saddles} of the Helmholtz free energy, located inside the spinodal region.Comment: 4 pages, Latex - 3 EPS Figs - Submitted to Phys. Rev.

Diffractive photoproduction of opposite-charge pseudoscalar meson pairs at high energies

We calculate the cross section for diffractive photoproduction of opposite-charge pseudoscalar meson pairs $M^+M^- = \pi^+ \pi^-$, $K^+ K^-$, $D^+ D^-$ and $B^+ B^-$ in a broad range of center-of-mass energies relevant for GlueX/Hall D, FOCUS, COMPASS and HERA experiments. In the case of $\pi^+\pi^-$ production we find that the interference of the $\rho^0$ resonance and the two-pion continuum leads to a considerable deformation of the shape of $\rho^0$ in agreement with the data from the ZEUS collaboration. We also discuss the spectral shape of the $\rho^0$ as a function of the momentum transfer and the contribution of higher partial waves to the $\pi^+\pi^-$ mass spectrum. We predict a sizeable energy-dependent forward-backward asymmetry in the Gottfried-Jackson frame. For the heavy meson production we find that the cross section for diffractive production increases much slower than the one for open charm or bottom production. We discuss lower and upper limits for the cross sections for diffractive production of $D^+ D^-$ and $B^+ B^-$ pairs, which we find can be as large as 10% of the open flavor production.Comment: 14 pages, 19 figure

Pengaruh Dari Penggunaan Superplasticizer Terhadap Rheology Pasta Dan Mortar Dengan Cementitious Materials

Tercapainya kualitas dari suatu beton merupakan hal yang paling utama. Dalam proses pembuatan suatu beton banyak faktor yang mempengaruhi kualitas beton seperti air, aggregat, admixture, dan cementitious materials. Suatu campuran beton biasa yang menggunakan air, semen, aggregat halus, dan aggregat kasar masih terdapat banyak rongga – rongga, cementious material seperti silica fume dapat mengisi rongga tersebut sehingga didapatkan campuran yang lebih padat. Selain hal tersebut, pada penelitian ini mengukur kualitas dari mortar untuk menentukan sifat dari beton segar seperti kelecakan, berat jenis, kehilangan berat, dan kuat tekan dalam beton. Rheology suatu campuran dipengaruhi oleh rasio dari volume air dan powder (Vw/Vp) dan juga penggunaan superplasticizer. Penelitian dalam skala kecil ini harus lebih diperhatikan setiap material yang dipakai dan proses pelaksanaanya.Pada penelitian ini didapat bahwa campuran Mortar dengan tambahan fly ash paling menghasilkan Perubahan diameter dan kuat tekan yang bagus, hal ini disebabkan fly ash memiliki kebutuhan air yang sedikit jika dibandingkan dengan campuran Mortar saja ataupun dengan penambahan silica fume

Nonlinear mechanics with photonic crystal nanomembranes

Optomechanical systems close to their quantum ground state and nonlinear nanoelectromechanical systems are two hot topics of current physics research. As high-reflectivity and low mass are crucial features to improve optomechanical coupling towards the ground state, we have designed, fabricated and characterized photonic crystal nanomembranes, at the crossroad of both topics. Here we demonstrate a number of nonlinear effects with these membranes. We first characterize the nonlinear behavior of a single mechanical mode and we demonstrate its nonlocal character by monitoring the subsequent actuation-related frequency shift of a different mode. We then proceed to study the underlying nonlinear dynamics, both by monitoring the phase-space trajectory of the free resonator and by characterizing the mechanical response in presence of a strong pump excitation. We observe in particular the frequency evolution during a ring-down oscillation decay, and the emergence of a phase conjugate mechanical response to a weaker probe actuation. Our results are crucial to understand the full nonlinear features of the PhC membranes, and possibly to look for nonlinear signatures of the quantum dynamics