Investigation of the 0.4C-35Cr-45Ni-Nb Alloy after Service in High-Temperature Steam and Hydrocarbons Environment

The paper presents the results of investigation of the 0.4C-35Cr-45Ni-Nb alloy, which operated in the cracked hydrocarbon feeds and dilution steam at 1125 °C. The material originated from the pyrolytic furnace coil tubes, of which internal walls were in contact with the aforementioned medium, whereas the external walls were in contact with the flue gases. The examination included metallographic and mechanical tests on the material after service exposure, the results of which were compared with the ones obtained for the as-received non-exposed specimens. The metallographic tests revealed changes in the alloy’s structure manifested by formation of significant amount of the carbides due to carburization of the alloy from the steam and cracked hydrocarbon feeds side. The central and external parts of the alloy samples (having no contact with the process medium) underwent substantial degradation but within a relatively narrow zone of the material. The investigations of hydrogen and methane content in the alloy showed a high amount of these gases, resulting from high-temperature corrosion in steam environment. The mechanical tests demonstrated clear shortening of the plastic deformation range of the alloy due to penetration of the gases and formation of the carbides inside the material’s structure. A low level of corrosion and no creep mechanism were detected.

‘The Research is Conducted…’: An Exploration of a Grammatical Metaphor Syndrome in Indonesian Research Articles

The research examined the use of one grammatical metaphor (hereafter GM) syndrome frequently found in Indonesian language research articles (hereafter RAs). This syndrome followed the lexicogrammatical structure of Process+Range or Process+Medium. An interesting feature of this GM syndrome, which, to date, had not been studied, was that while GM typically increased the lexical density of a clause by condensing meaning into nominal groups. This GM syndrome seemed to do the opposite. e.g., rather than writing ‘merubah’ (changed) as Process, writers used ‘melakukan perubahan’ (do some changes), which had the structure of Process+Range. This had the effect of delexicalizing the verb as well as increasing the number of words in the clauses. Instead of seeing this form as a mere ritual in academic writing, the research sought to understand the functional role in the RAs. The data was taken from a small corpus of RAs from two refereed Indonesian humanities journals. The occurrences of this GM syndrome were identified. A systemic analysis was then conducted with a metafunctional lens, examining the ideational, interpersonal, and textual functions of this form of GM syndrome. The analysis reveals that ideationally, GM syndrome is a resource to manage technicality, abstraction, taxonomy, and activity sequence; textually, the syndrome is a resource organizing textual coherence through the management of hyperThemes; and interpersonally, the syndrome functions as a resource for Graduation, which decreases the force of propositions.

Research of energy-saving vibration machines with account of the stress-strain state of technological environment

An analytical method for determining the influence of a process medium on the dynamics of the working bodies of vibrating machines is considered. The results of the research are presented, which made it possible to identify the zones of effective action of parameters and characteristics of the "machine - environment" system to ensure the high quality of the compaction process, which is based on the idea of purposeful use of the elastic characteristics of a common vibration system. The scientific idea is put forward, which consists in the fact that during the study of a particular process the mathematical model of the vibration system "machine-environment" should be determined on the basis of taking into account the internal structure of these subsystems as a single one, despite their different physical nature and structure. The theoretical substantiation of the possibility of creating bulk molding Vibration Machines with highly effective parameters of energy intensity and material consumption for various conditions for the formation of concrete and reinforced concrete products is given in the paper. This is due to the creation and rational use of the regularities of changes in the internal (elastic-inertial and dissipative) properties of the "machine-environment" system in the regime, which is approximate to the mode of its free oscillations.

Pengaruh Laju Alir Umpan dan Arus Recycle Terhadap Proses Fermentasi Bioetanol Menggunakan Integrated Aerobic-Anaerobic Baffled Reactor (IAABR)

<div class="WordSection1"><p><strong>Abstract.</strong> Petroleum based fuel is the main energy source used in the world. However, there is a future problem with the declined petroleum reserves. Therefore changing to alternative energy resource is a must. This reserach was to investigate the effects of feed flowrate and recycle flow rate on bioethanol fermentation process using integrated aerobic-anaerobic baffled reactor, especially on bioethanol production and sugar consumption. Start up process was run with working volume of 25 L medium for 54 hours incubation. The recycle flow varried into 5 L/h and 10 L/h when the feed rate was 12.6 L/h. In other experiments, the feed flow rate was run at 5 and 12.6 L/h when the recycle flow rate was 10 L/h. The broth samples were taken out periodically for measurements of bioethanol concentration, yeast population and residual sugar of consumptions. The experiments results in the highest bioethanol concentration of 14% v/v at the effluent of reactor. It is higher from the process without recyle of process medium. Nevertherless, no difference effect of the recycle flow rate of 5 L/h and 10 L/h on the bioethanol production.</p><p> <strong>Keywords:</strong> Bioethanol, Baffled Reactor, Feed, Recycle</p></div>

PARTISIPASI MASYARAKAT DALAM PENYUSUNAN RENCANA PEMBANGUNAN JANGKA MENENGAH DAERAH (RPJMD) KOTA PEKANBARU 2012-2017

Status: Postprint di Jurnal PUBLIKa Jilid 2 Terbitan April dan Oktober Halaman 48-58The region authority to controlling the development planning contained in a regulations No. 25 of 2014 about the system of development planning. The regulation give an opportunity to the public to become involved in every process of development especially in the long-term process, medium-term although short-term. Medium-term development plan (RPJMD) become the important ones to every region especially Peknbaru city, because this formula was an elaboration of the vision and mission of regional head (Walikota) as well as executives products that directly related to the policies of city government development. As part of the process of formulating the development plan, the discussion of development planning (musrenbang) was the only step where the public get the chance to participate. Through a descriptive qualitative approach by the ethic data analysis and emic, concluded that the public participate in the discussion of development planning RPJMD of Pekanbaru city fully initiated by the government of Pekanbaru city, there was nothing mobilitation from the government to the public in musrenbang because the public voluntary attendance for the invitation, participation from the formal way and group and also there was nothing informal way, so this participation has not been effective because the public were not involved from the start in the formulations of the RPJMD, so that the public still seen as a subject in the development planning.Key word: participation, social changes and development, RPJMD.

Numerical Study of Dynamic Behavior of Joule-Heated Pool

In the present numerical study, we consider a low-Prandtl liquid metal heated by Joule effect in a rectangular cavity with an aspect ratio of 2. The direct current provides heat to the process medium by a pair of plate electrodes, located at the cavity sidewalls. The simulations have been carried out using finite volume method for fixed values of the Prandtl number, Pr=0.01, and of the Rayleigh number, Ra=1.5×104, while the Hartmann number, Ha=1410, Comparison between the original noise-free data and cleaned data is explored. More precisely, accurate performances predicted using removing noise from numerical simulation data is obtained to define the inherently complicated nature of the competition of buoyancy with electromagnetic body forces.