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[en] Shell and Tube type Oil Cooler is widely used for hydraulic presses, die casting machines, generation equipments, machine tools and construction heavy machinery. Temperature of oil in the hydraulic system changes viscosity and thickness of oil film. They have a bad effect to performance and lubrication of hydraulic machinery, so it is important to know exactly the heat exchanging efficiency of oil cooler for controlling oil temperature. But most Korean manufacturers do not have test equipment for oil cooler, so they cannot carry out the efficiency test of oil cooler and it is impossible to verify its performance. This paper includes information of construction of necessary utilities for oil cooler test and design and manufacture of test equipment. One can select the optimum product by obtaining performance data through tests of various kinds of oil coolers. And also the paper developed a program which can be easily used for design of 2D and 3D drawings of oil cooler
[en] Power consumption in the oil mixing process is very much affected by the impeller design. Minor modification on the impeller design might result in better mixing and less energy consumption. This paper reports an early stage of applying the observation technique to modify three standard impellers, namely the Pitched blade turbine impeller, the CHEMSHEAR impeller and the Vertical Flat-Blade Turbine Impeller. The advantages and disadvantages of these three impellers were analyzed; accordingly minor modification on the impeller design is adopted. The CFD tool is used to evaluate one of the modified impellers; results indicated that the modified impeller achieves better fluid dispersion.
[en] A quality by design approach was used to investigate the influence of formulation composition and spray drying conditions on physicochemical properties of redispersable lipid based nanosystems loaded with Syzygium aromaticum essential oil. Four critical independent variables were studied: presence or absence of the liquid lipid oleic acid (0% - 1%), of the cationic surfactant CTAB (0% and 1%), inlet drying temperature (60 oC -80 oC), and ratio of the drying aids (ADJ)regarded to total formulation constituents weight (1:1 and 2:1). Resuls showed the production of spray dried redispersable lipid systems loaded with essential is feasible under very restrict conditions. (Author)
[en] The aim of this work is to study the effects of drying conditions on the quality of extracted pricly pear seed oil, specifically α-tocopherol content. Drying experiments were carried on following a full 23 factorial design using a vertical drying tunnel. The temperature range was 45 to 70°C, relative humidity range was 15 - 30% and air velocity was 1 and 2 m/s. The Midilli- Kucuk model was found with satisfaction describing the seed air drying curves with a correlation coefficient of 0.999 and a standard error of 0.01. For each drying condition, the extraction of fixed oil seeds was performed at cold using mechanical pressing method. The oil quality was evaluated on the basis of the α-tocopherol content. The α-tocopherol was identified and quantified by high-performance liquid chromatography (HPLC-UV). According to the experimental results, it was found that convective drying of thin layer of seeds at soft air conditions, drying temperature of 45°C, relative humidity of 15% and air velocity of 1m/s give the optimal quality of extracted oil in terms of α-tocopherol content. (Author)
[en] Although phosphoenolpyruvate carboxylases (PEPCs) are reported to be involved in fatty acid accumulation, nitrogen assimilation, and salt and drought stresses, knowledge regarding PEPC gene functions is still limited, particularly in peanuts (Arachis hypogaea L.). In this study, the antisense expression of the peanut PEPC isoform 1 (AhPEPC1) gene increased the lipid content by 5.7%–10.3%. This indicated that AhPEPC1 might be related to plant lipid accumulation. The transgenic plants underwent more root elongation than the wild-type under salinity stress. Additionally, the specific down regulation of the AhPEPC1 gene improved the salt tolerance in peanuts. This is the first report on the role of PEPC in lipid accumulation and salt tolerance in peanuts.
[en] This order provides for the organization and attributions of divisions and departments of the Statistics Directorate of the Ministry of Energy and Oil. This direction has two divisions namely Division for Energy Statistics and Division for Oil Statistics . Energy Statistics Division includes the following services: Service collection and data analysis for energy statistics and the service of production, dissemination and conservation of energy statics. The division for Oil Statistics includes the Service collection and data analysis for energy statistics and the service of production, dissemination and conservation of energy statistics.
[fr]Cet arrete porte sur l'organisation et les attributions de la Direction des Statistiques du Ministere de l'Energie et du Petrole. Cette direction comprend deux divisions a savoir la Division des Statistiques Energetiques et la Division des Statistiques Petrolieres. la Division des Statistiques Energetiques regroupeles services suivants: service collecte et analyse des donnees statistiques energetiques et le service production, diffusion et conservation des statistques energetiques. Celle des Statistques Petrolieres est constituee du service collecte et analyse des donnees statistiques petrolieres et du service production, diffusion et conservation des statistiques petrolieres.
[en] A method is described for forming thin free-standing oil films which are spun from the edge of a sharp-edged rotating disc. The films can be made thin enough to show strong optical interference colors when viewed in white light. The thinnest films have areal densities down to about 10-20 μg/cm2. A stable roughly triangular film with an area of about 10 cm2 and fairly uniform thickness can be readily produced. Much larger films having either greater thickness or less stability are also possible. Films have been produced both in air and in vacuum. (orig.)
[en] The correlation between the coma sensitivity of the alternating phase-shifting mask (Alt-PSM) mark and the mark's structure is studied based on the Hopkins theory of partially coherent imaging and positive resist optical lithography (PROLITH) simulation. It is found that an optimized Alt-PSM mark with its phase width being two-thirds its pitch has a higher sensitivity to coma than Alt-PSM marks with the same pitch and the different phase widths. The pitch of the Alt-PSM mark is also optimized by PROLITH simulation, and the structure of p=1.92λ/NA and pw=2p/3 proves to be with the highest sensitivity. The optimized Alt-PSM mark is used as a measurement mark to retrieve coma aberration from the projection optics in lithographic tools. In comparison with an ordinary Alt-PSM mark with its phase width being a half its pitch, the measurement accuracies of Z7 and Z14 apparently increase
[en] Investigations of major accidents show that technical, human, operational, as well as organisational factors influence the accident sequences. In spite of these facts, quantitative risk analyses of offshore oil and gas production platforms have focused on technical safety systems. This paper presents a method (called BORA-Release) for qualitative and quantitative risk analysis of the platform specific hydrocarbon release frequency. By using BORA-Release it is possible to analyse the effect of safety barriers introduced to prevent hydrocarbon releases, and how platform specific conditions of technical, human, operational, and organisational risk influencing factors influence the barrier performance. BORA-Release comprises the following main steps: (1) development of a basic risk model including release scenarios, (2) modelling the performance of safety barriers, (3) assignment of industry average probabilities/frequencies and risk quantification based on these probabilities/frequencies, (4) development of risk influence diagrams, (5) scoring of risk influencing factors, (6) weighting of risk influencing factors, (7) adjustment of industry average probabilities/frequencies, and (8) recalculation of the risk in order to determine the platform specific risk related to hydrocarbon release. The various steps in BORA-Release are presented and discussed. Part II of the paper presents results from a case study where BORA-Release is applied
[en] Despite the oil industry's efforts in improving safety, it still presents a high rate of serious accidents, many involving human failure events (HFE), which can be identified, modelled, and quantified through human reliability analysis (HRA). The oil industry commonly analyzes process safety by focusing on technical barriers, and thus it could benefit from HRA. Phoenix methodology is an HRA method that uses a human response model and relates the crew failures modes (CFM) to performance influencing factors (PIFs). Based on Phoenix CFMs and PIFs, two refinery accidents, the BP Texas City (2005) and the Chevron Richmond (2012), are analyzed in this paper. The analysis consists of the construction of the accident timeline; identification of the HFEs and assigning them to appropriate CFMs; and, finally analysis of the PIFs. The analysis helped better understand how the operators responded to an abnormal condition of the process, and why they took the actions they did, investigating the contribution of human error to the accidents. The assessment of the role human error played in these accidents is a major contribution to the understanding of why they happened, and a key information to avoid the same happening again in the future. Moreover, the features and limitations of the application of Phoenix HRA, which was developed based mainly on nuclear power plant operations, to Oil Refinery operation scenarios, are discussed and evaluated. This article provides insights on value of investigating the potential impact of human error in the Petroleum Industry accidents. (author)