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Search Results: 1 - 10 of 322232 matches for " Bigeard P. H. "
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L'hydrocraquage : une solution simple pour produire des distillats moyens de haute qualité Hydrocracking: a Flexible Solution for Producing High Quality Middle Distillates
Espinosa A.,Bigeard P. H.,Marion P.
Oil & Gas Science and Technology , 2006, DOI: 10.2516/ogst:1994034
Abstract:
Ifp's New Flexible Hydrocracking Process Combines Maximum Conversion with Production of High Viscosity, High Vi Lube Stocks Le nouveau procédé IFP d'hydrocraquage à haute flexibilité combine conversion maximum et production de bases, huile à haute viscosité et à indice de viscosité élevé
Hennico A.,Billon A.,Bigeard P. H.,Peries J. P.
Oil & Gas Science and Technology , 2006, DOI: 10.2516/ogst:1993010
Abstract: Institut Fran ais du Pétrole (IFP) has developed a new dual catalytic system for its hydrocracking process that enables high conversion to middle distillates and production of high viscosity, high VI lube stocks. Although the hydrocracking process is mainly devoted to the conversion of vacuum distillates, deasphalted oil or mixture of both into high quality middle distillates, it can also produce a residue, that after dewaxing will be a very high VI lube base oil. In this presentation major emphasis is put on the possibility to produce very high VI lubes with high viscosity thanks to the development of the new catalytic system. Large flexibility in feedstock selection and easy control of operating variables allow the production of all grades of lube oils associated with high quality middle distillates for a large range of conversion levels. L'Institut Fran ais du Pétrole (IFP) a mis au point, pour son procédé d'hydrocraquage, un nouveau système catalytique à 2 catalyseurs qui permet une forte conversion en distillats moyens et la production de fractions lubrifiantes à haute viscosité et indice de viscosité élevé. Si le procédé d'hydrocraquage est essentiellement utilisé pour la conversion de distillats sous vide, d'huile désasphaltée ou d'un mélange des deux en distillats moyens de haute qualité, il peut aussi produire un résidu qui, après déparaffinage, fournira une base pour lubrifiant à indice de viscosité très élevé. Cet article souligne particulièrement la possibilité de produire des lubrifiants à indice de viscosité très élevé et haute viscosité, grace à ce nouveau système catalytique. Une grande flexibilité dans le choix des produits à traiter et la facilité de contr le des paramètres opératoires permet la production de toutes les qualités d'huiles lubrifiantes associées à des distillats moyens de haute qualité, pour une large gamme de niveaux de conversion.
Efficient FPGA implementation of AES 128 bit for IEEE 802.16e mobile WiMax standards  [PDF]
P. Rajasekar, Dr. H. Mangalam
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.74032
Abstract: In an advancement of communication field, wireless technology plays a predominant role in data transmission. In the timeline of wireless domain, Wi-Fi, Bluetooth, zigbee etc are some of the standards, which are being used in today’s wireless medium. In addition, the WiMax is introduced by IEEE in IEEE 802.16 for long distance communication, specifically 802.16e standard for mobile WiMax. It is an acronym of Worldwide Interoperability for Microwave Access. It is to be deliver wireless transmission with high quality of service in a secured environment. Since, security becomes dominant design aspect of every communication, a new technique has been proposed in wireless environment. Privacy across the network and access control management is the goal in the predominant aspects in the WiMax protocol. Especially, MAC sub layer should be evaluated in the security architecture. It has been proposed on cryptography algorithm AES that require high cost. Under this scenario, we present the optimized AES 128 bit counter mode security algorithm for MAC layer of 802.16e standards. To design a efficient MAC layer, we adopt the modification of security layers data handling process. As per the efficient design strategy, the power and speed are the dominant factors in mobile device. Since we concentrate mobile WiMax, efficient design is needed for MAC Security layer. Our proposed model incorporates the modification of AES algorithm. The design has been implemented in Xilinx virtex5 device and power has been analyzed using XPower analyzer. This proposed system consumes 41% less power compare to existing system.
Damping Factor Estimation of a Flexible-Matrix-Composite Body Pump  [PDF]
N. P. Kumar, H. Ghoneim
Journal of Materials Science and Chemical Engineering (MSCE) , 2016, DOI: 10.4236/msce.2016.47009
Abstract:

Two very important factors which determine the effectiveness of a pump are its volumetric and power efficiencies. Yin and Ghoneim constructed a prototype of a Flexible-Matrix-Composite (FMC) body pump with a very high volumetric efficiency or pumping potential (the relative volume reduction due to a relative input stroke). The high volumetric efficiency is attributed to the geometry of the pump’s structure (hyperboloid) as well as the high negative effective Poisson’s ratio of the 3-layer [θ/β/θ] flexible-matrix-composite (carbon/polyurethane) laminate adopted for the body of the pump. However, the power efficiency of the pump was not evaluated. It is the objective of the current paper to obtain an estimate of the power efficiency of the pump. The viscoelastic properties of the 3-layer FMC (carbon/polyurethane) laminate are evaluated experimentally using the Dynamic Mechanical Analyzer (DMA) as well as analytically by applying the correspondence principle together with the micro-mechanics approach. In order to obtain an estimate of the power efficiency of the FMC body pump, the axial and shear loss factors of a laminated infinitely long cylindrical tube as functions of β and θ fiber orientation angles are determined employing the Adam and Bacon approach. The analysis engenders high loss factors (greater than 0.4), which suggests that the power efficiency of the proposed pump using the 3-layer carbon/polyurethane laminate may be low.

Synthesis and Characterization of a [Li0+xMg2-2xAl1+x(OH)6][Cl·mH2O] Solid Solution with X = 0 - 1 at Different Temperatures  [PDF]
A. Niksch, H. P?llmann
Natural Resources (NR) , 2017, DOI: 10.4236/nr.2017.86029
Abstract: The synthesis of a novel Li+ /Mg2+ /Al3+ containing layered double hydroxide (LDH) by using a hydrothermal synthesis route is represented in this work. The autoclaves were heated up to 100oC, 120oC, 140oC and 160oC for 10 h and 48 h with a water to solid ratio (W/S) of 15:1. The physicochemical properties of the synthesized LDHs were investigated by X-ray powder diffraction (PXRD), fourier transform infrared spectroscopy (FTIR), thermo gravimetric and differential thermal analysis (TG-DTA), inductively coupled plasma optical emission spectroscopy (ICP-OES) and scanning electron microscopy (SEM). The formation of a solid solution phase depends strongly on the composition of the reactants and the synthesis temperature. Using an exact stoichiometric ratio of Li+/Mg2+/Al3+ resulted in the synthesis of amorphous phases without producing plenty of crystalline amounts of the expected solid solutions while using higher temperatures than 140oC resulted in a formation of AlO(OH). To avoid the formation of an Al containing amorphous phase or an AlO(OH) crystalline phase, the stoichiometric ratio of Li+ was changed. The results show solid solutions with the formula [Li0+xMg2-2xAl1+x(OH)6][Cl.mH2O] with X ≥ 0.9. The lattice parameters and chemical compositions for solid solutions with different compositions were determined and the pure solid solution with the highest amount of Mg (x = 0.9) is [Li0.9Mg0.2Al1.9(OH)6] [Cl.0.50H2O] with the lattice parameters a = 5.1004(4) Å, c = 15.3512(1) Å, V = 345.844(9) Å3. For X < 0.9 two separate phases, a Mg2+ and a Li+ dominated solid solution, are coexistent.
An IEEE 1547-Based Power Conditioner Test System for Distributed Energy Resources  [PDF]
Azen Y. Liu, P. H. Lan, H. H. Lin
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B181
Abstract:

Power conditioner, that is responsible for electric power conversion, is a critical component used in many renewable energy power generation systems. Most of the electric power produced by distributed energy resources cannot directly import to utility network without power conversion. Meanwhile, power conversion may includes several different types, for example AC/DC, and DC/AC, which is realized by a variety types of power conditioners in the electric power system. Currently, many concerns are focused on the operation of these power conditioners used in distributed energy resources due to the worse designing may cause the terrible influence on safety and performance characteristic of distributed energy resources. The power quality and reliability of interconnected electric power network may be affected as well. In the view of this, IEEE standards board provides a uniform standard for interconnection of distributed resources with electric power systems. It provides requirements relevant to the performance, operation, testing, safety considerations, and maintenance of the interconnection. Based on the IEEE 1547 standard, this paper presents a test system for power conditioners that are used in distributed energy resources or other renewable energy applications. Some of the test items that described in IEEE 1547.1 relevant to interconnection issues can be realized by proposed test system.

Nutritional, Physicochemical and Microbial Quality of Ultrasound-Treated Apple-Carrot Juice Blends  [PDF]
Jingfei Gao, H. P. Vasantha Rupasinghe
Food and Nutrition Sciences (FNS) , 2012, DOI: 10.4236/fns.2012.32031
Abstract: Three different apple-carrot juice blends (60:40, 75:25 and 90:10, v/v) were prepared and treated with ultrasound with comparison to the conventional thermal pasteurization. Total aerobic viable count (TAC) were significantly lower in juice blends with lower pH (apple-carrot ratio of 90:10, v/v) than the blends with higher pH after one month storage at 4?C. TAC were similar in ultrasound-treated and thermal pasteurized juice blends. Changes of turbidity of juice during storage followed the same pattern of TAC. Other juice quality parameters such as color, pH, titratable acid, total soluble solids, antioxidant capacity and beta-carotene did not change significantly during the storage period. The results suggest that ultrasound treatment has a potential to use as an alternative non-thermal technique for traditional thermal pasteurization process for maintaining the quality of beverages prepared from fruit and vegetable juices.
The Two-Constant Cost Model and the Estimation of the Cost Performance Evolutions of the Proton Exchange Membrane Fuel Cell Power Generation  [PDF]
H. F. Zhang, P. C. Pei
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.52A001
Abstract:

This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. For this purpose, electricity-cost ratio (ECR) is proposed as the measuring parameter for the cost performance and a two-constant cost model is proposed to concisely describe the cost characteristic of the power generation as the opposite of a multi-constant cost model. Combination of the two-constant cost model and the ideal cell model developed recently produces an inclusive ECR equation that has three analytical expressions and thus allows of straight overviews of the cost performance evolutions in the working zones of the cells. The applications to real cells confirm the validity of the equation for operation optimization and technique evaluation of PEM fuel cells. And more insights into the cost performance evolutions are inferred by means of the equation to help promote the commercialization of PEM fuel cells.

Discrimination and Estimation of the Maximum Cost Performance of Proton Exchange Membrane Fuel Cell Power Generation with Seven Constants  [PDF]
H. F. Zhang, P. C. Pei
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.52A008
Abstract:

This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation.

Asymptotic Harmonic Behavior in the Prime Number Distribution  [PDF]
Maurice H. P. M. van Putten
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.516244
Abstract: We consider \"\" on x > 0, where the sum is over all primes p. If Φ is bounded on x > 0, then the Riemann hypothesis is true or there are infinitely many zeros \"\". The first 21 zeros give rise to asymptotic harmonic behavior in Φ(x) defined by the prime numbers up to one trillion.
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