Journal articles: '+316.614'

1

He, Yi, Zhao Yao Zhou, Wen Jiong Cao, and De Zhi Yang. "Numerical Simulation of Solidification by SPH in Sand Cast Process." Advanced Materials Research 314-316 (August 2011): 614–19. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.614.

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In this paper, Smoothed Particle Hydrodynamics (SPH) was used for the prediction of heat conduction problems in sand cast process. The implementation of solidification modeling in a curved casting based on SPH has been described. The treatment of latent heat was introduced in SPH conduction problem by temperature compensation method, which demonstrated the role of latent heat has a great influence on the heat distribution in the casting. The temperature distribution calculated by SPH provided a great agreement with those computed through numerical software MSC.Marc, which validated the efficiency and precision of SPH simulation of heat transfer problems in sand cast process.

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2

Kurunina, G. M., O. M. Ivankina, and G. M. Butov. "Hydrogenation of Nitro Compounds over Catalytic Systems Containing Rare-Earth Oxides." Solid State Phenomena 316 (April 2021): 684–88. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.684.

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The paper studies the activity of 1 % palladium catalysts containing rare earth oxides (REOs) and alumina as a carrier in the hydrogenation of nitro compounds exemplified by nitrobenzene and o-nitro anisole. Under the liquid-phase hydrogenation conditions, these catalytic systems provide high selectivity of the process and a quantitative yield. It has been found that the partial replacement of Al2O3 with REO allows increasing the hydrogenation rate by 5–6 times, as compared with the reference catalyst and by 1.2–1.7 times as compared with the individual carrier. The oxide mixtures (REO and Al2O3) containing 20–40 % REO allow reaching the same hydrogenation rate with that over an REO-containing 1 % Pd catalyst.

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3

Bobkov, V. I., M. I. Dli, and A. S. Fedulov. "Mathematical Model for the Kinetics of Heterogeneous Reaction of Carbonates Dissociation in the Process of Roasting in the Presence of Temperatures Gradients in Phosphate Raw Material." Solid State Phenomena 316 (April 2021): 610–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.610.

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The paper deals with the investigation of the parameters for the structural and kinetic rate equation of the carbonates dissociation reaction, in accordance with the obtained results of the nonisothermic experiment, in the conditions of gradient temperature presence in the investigated samples. The most significant is the study of physicochemical transformations kinetic laws, which degree of completeness effects the quality of intermediate products directly, that is decarbonization and sintering. The main part of the process, when phosphorites are heated, takes place in a solid phase. The feature of topochemical reactions is their localization in the aria between a solid phase surface of the initial substance and the reaction products. This surface is formed and changed, as a result of chemical and power technological process for roasting, determining the dependence of the reaction rate on time. The method of thermal analytical experiments is used. The reverse kinetic problem is solved in the temperatures range of the chemical–technological process for roasting phosphate raw materials on conveyor indurating machines. The authors propose a method of approximate calculation for the parameters of kinetic equations which allows to reduce errors, caused by the heat exchange processes in a measuring cell, significantly. The obtained results and their accuracy are suitable for the practical application.

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4

Chaikin, L. I., A. E. Kireev, and Irina V. Loginova. "Studying the Possibility of Obtaining Titanium Powder of Various Sizes by Alumino-Thermic Reduction." Solid State Phenomena 316 (April 2021): 619–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.619.

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The main aim of this work is to obtain a compact spherical titanium powder by the metallo-thermic reduction. The feedstock is TiO2 (rutile), and aluminum shavings are used as the reducing metal. In the reduction process granules of titanium powder and corundum were obtained. For cleaning titanium powder from corundum, various alkaline and acid processing methods were used. When using the alkaline treatment method of the powder, obtained after reduction of sand and floury rutile by aluminum shavings, its weight decrease was 36-37%.

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5

Kolmachikhina, O. B., S. E. Polygalov, and K. A. Vakula. "The Study of Physicochemical Features of Laterite Ores of the Buruktalsky Deposit." Solid State Phenomena 316 (April 2021): 694–98. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.694.

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Currently, there are practiced various pyrometallurgical, hydrometallurgical, and com-bined pyro and hydrometallurgical methods for processing of oxidized nickel ores to produce metal-lic nickel, cobalt, and their compounds in non-ferrous metallurgy. The problem is the difficult ore concentration, and consequently the high consumption of reagents or low extraction of valuable components from it. Ural plants previously implemented the technology of reducing-sulphiding smelting of laterite ore to produce fire nickel and transfer of cobalt to matte. The economic ineffi-ciency of this technology predetermined the search for a new method for processing of significant reserves of oxidized nickel ores in the Ural region.

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6

Qiu, Li, Yi Liang Lv, Cheng Xi Jiang, Xiao Tao Han, and Liang Li. "Numerical Analysis of the Workpiece Velocity in Electromagnetic Forming Process." Advanced Materials Research 314-316 (August 2011): 634–38. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.634.

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The effect of the motional electromagnetic force in the electromagnetic forming circuit on the workpiece velocity is analyzed. The differential equations of unconsidering and considering the motional electromagnetic force in the electromagnetic forming circuit are solved numerically. The results without considering the motional electromagnetic force are unavailable because they violate the law of conservation of energy, while the results with considering the motional electromagnetic force can accurately reflect the electromagnetic forming process. Furthermore, it is found that the electrical energy transforms into the kinetic energy due to the motional electromagnetic force.

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7

Yang, Ji Chang, Jian Zhong Zhou, Yong Kang Zhang, Su Min Yin, Ai Xin Feng, and Dun Wen Zuo. "Ultra-Speed Plastic Deformation of TC6 Sheet Induced by Laser Shock Loading." Key Engineering Materials 315-316 (July 2006): 612–16. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.612.

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8

Lu, Ze Sheng, and Ming Hai Wang. "Optimization of Cutting Conditions in Ultra-Precision Turning Based on Mixed Genetic-Simulated Annealing Algorithm." Key Engineering Materials 315-316 (July 2006): 617–22. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.617.

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In ultra-precision turning process, the predictive modeling of surface roughness and the optimization of cutting conditions are the key factors to improve the quality of products and raise the efficiency of equipments. In this paper, the application of genetic algorithm in identifying nonlinear surface roughness prediction model is discussed, and presents mixed genetic-simulated annealing algorithm approach to optimization of cutting conditions in ultra-precision turning. The experiment was carried out with diamond cutting tools, for machining single crystal aluminum optics covering a wide range of machining conditions. The results of fitting of prediction model and optimal cutting conditions using genetic algorithm (GA) are compared with least square method and traditional optimal method.

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9

Wei, Xin, Rui Wei Huang, Shao Hui Lai, and Z. H. Xie. "Vibration Analysis of ID Slicing Process and Wafer Measurement." Key Engineering Materials 315-316 (July 2006): 641–45. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.641.

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ID (inner-diameter) slicing is widely used in cutting ingots currently. In this paper, the deflection (axial vibration) and vibration (radial vibration) signals in different slicing conditions of the silicon wafers were measured online and analyzed. The effects of the vibration signals on the machining accuracy and surface roughness of sliced wafers were investigated based on the measurement and analysis of the surface roughness, warpage and TTV (total thickness vibration) of the sliced wafers. The results show that the changes of surface roughness, warpage and TTV of the sliced wafers exhibit approximately consistence with the changes of the power spectrums of the acquired vibration signals in different working stage of the blade. The vibration and deflection signals can give evidence of the changes in the cutting forces and blade performance during slicing. The power spectrum of the signals is useful for monitoring the blade wear and tension condition and predicting the surface quality and machining accuracy of the sliced wafers.

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10

Li, Xiang Feng, Zhong Shan Wei, Dun Wen Zuo, and Min Wang. "Corrosion Resistance of TC4 Alloy Implanted by La⁺, Mo⁺." Key Engineering Materials 315-316 (July 2006): 61–65. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.61.

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The surface treatment for TC4 alloy was conducted by MEVVA ion implantation method. The corrosion resistance of TC4 alloy implanted by La+, Mo+ were measured. It were found that Mo ion implantation improved corrosion resistance of TC4 alloy in acidic chloride solution, but La ion implantation gave the opposite result because they have different chemical activity. The more implanted dose of Mo+, the more improvement of corrosion resistance.

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11

Ponurko, I. V., S. A. Krylova, A. S. Limarev, and I. Y. Mezin. "The Use of Phosphate Compositions for Chemical Treatment of Make-Up Water in Centralized Heat Supply Systems." Solid State Phenomena 316 (April 2021): 605–9. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.605.

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The paper investigates two different protective phosphate compositions for the chemical treatment of water and the use of them with a view to improve quality of “make-up” water in water heating systems. The research proved a positive effect of reducing the corrosive activity of water and the amount of scale.

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12

Loginova, Irina V., and Aleksei V. Kyrchikov. "The Study of the Magnetic Properties of Red Mud from Alumina Production after Alkaline Treatment." Solid State Phenomena 316 (April 2021): 673–77. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.673.

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In Russia, the main feedstock for producing aluminum is bauxite. During the processing of 1 ton of bauxite into alumina (Al2O3), up to 0.5–0.6 ton of techno-genic waste is formed, that is red mud. It is not currently disposed of and accumulated in mud tailing dumps. It contains valuable components: Al – 8 %; Fe – 25 %; Ti – 2.4 % and it can be considered as a potential raw material for ferrous metallurgy and as a source of vanadium, titanium, and rare-earth elements (REE) Sc, Y, La. The paper shows the possibility of obtaining red mud with an increased iron content of up to 36 %, with an additional extraction of aluminum. Red mud from the Ural Aluminum Plant (Russia) is considered. It is proposed to direct this mud to the production of pellets for the production of cast iron. To extract aluminum from red mud, it is proposed to process the mud in a highly alkaline medium by sintering in the temperature range 300–600 °C. The resulting sinter is leached with water or a slightly alkaline solution with the conversion of aluminum compounds into solution. The red mud, obtained this way, exhibits magnetic properties. A magnetic separation was carried out, and the yield of the magnetic fraction is 79.87 %. The iron content increases by 25 % and amounts to 51.88 % of Fe2O3.

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13

Anikin, Y. V., O. Yu Makovskaya, and V. I. Shilkov. "The Use of Hydrogen Peroxide and Hydrazine Sulfate for Removal of Chromium from Electroplating Effluents." Solid State Phenomena 316 (April 2021): 655–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.655.

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The use of hydrogen peroxide and hydrazine sulfate for the treatment of chrome-containing rinsing waters of galvanic production of machine-building enterprises is proposed. The process of reducing chromium (6+) to (3+) from rinsing waters with a concentration of 8.55 mg/dm3 was studied. These reagents allow reducing more than 99% of chromium (6+) to chromium (3+) and maintaining a low salt content of treated wastewater. The consumption of hydrogen peroxide is 1.5 mg/dm3, and the consumption of hydrazine sulfate is 10 mg/dm3. The current situation in the treatment of galvanic wastewater leads to pollution of the environment with dangerous substances (CN-, Cr6+, F-, Cd2+), irrational use of raw materials and significant economic losses. The possibility of extracting valuable components from wastewater, in order to recycle them and return the treated water to production, is considered. Hydrogen peroxide is effective for treating acidic wastewater, and hydrazine sulfate can be used for both acidic and alkaline wastewater. Removal of excess hydrogen peroxide from the solution after reduction of chromium (6+) before precipitation of chromium (3+) hydroxide is required. The toxicity of hydrazine compounds must be taken into account.

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14

Mokrova, Nataliya V. "Methods of Mathematical Modeling of the Leaching Process of Cobalt-Containing Solutions." Solid State Phenomena 316 (April 2021): 661–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.661.

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Current cobalt processing practices are described. This article discusses the advantages of the group argument accounting method for mathematical modeling of the leaching process of cobalt solutions. Identification of the mathematical model of the cascade of reactors of cobalt-producing is presented. Group method of data handling is allowing: to eliminate the need to calculate quantities of chemical kinetics; to get the opportunity to take into account the results of mixed experiments; to exclude the influence of random interference on the simulation results. The proposed model confirms the capabilities of the group method of data handling for describing multistage processes.

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15

Medyanik, Nadezhda L., Anton P. Ponomarev, and Olga V. Yershova. "The Chemical Technology for Producing Precious Metals from Enrichment Rejects of Copper-Pyrite Ores." Solid State Phenomena 316 (April 2021): 625–30. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.625.

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The chemical technology for recovery precious metals Au and Ag from mature flotation tailings of copper-pyrite ores by two-stage sintering with chlorine-ammonium reagents and leaching of bakes with water is developed. The chemical extraction of gold and silver is carried out, using NH4Cl and NH4NO3 reagents in the ratios of 1:1 at a temperature of 250 °C, and 2:1 at 200 °C. In accordance with the obtained results, a chemical technology of enrichment rejects of copper-pyrite ores processing and a scheme of primary apparatus chain for implementing this technology are proposed. The economic effect of the technology realization is calculated. This effect is 96.3 million rubles with a payback period of 8 years when processing enrichment rejects of copper-pyrite ores in amount of 109.5 thousand tons per year under the conditions of JSC “Uchaly Mining and Metallurgical Combine”.

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16

Tyutrin, Andrey A., and Andrey S. Vologin. "Analysis of the Composition and Properties of the Silicon Production Wet Cleaning Sludge to Identify Sustainable Techniques for its Processing." Solid State Phenomena 316 (April 2021): 649–54. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.649.

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The paper is devoted to the urgent issue of processing the dust waste of metallurgical-grade silicon production, i.e. wet cleaning sludge, which contains a significant amount of valuable silica. The paper analyzes the formation of finely dispersed techno-genic materials that are generated in significant quantities (up to 120 t/d) at the Kremniy JSC. The composition and properties of the silicon production wet cleaning product have been studied. In analytical studies of the wet cleaning sludge samples, the modern certified analysis techniques have been used: laser diffraction, X-ray diffraction, and X-ray fluorescence. According to the analysis, the L:S ratio of liquid sludge is 2.1:1; after dehydration, the sludge cake has a grain size of 150 μm, with the prevailing (90 %) grain size of 59.65 μm in the test sample. The chemical composition of the sludge is 95.86 % SiO2; therefore, the wet cleaning sludge is a valuable raw material to produce metallurgical-grade silicon. Based on the analysis of the composition and properties of the silicon production wet cleaning sludge sample, we have developed a program for its processing. Sustainable sludge processing techniques are aimed at obtaining a briquetted charge, which can be used as an additive to the main raw material.

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17

Nemchinova, Nina V. "Hydrometallurgical Processing of Spent Carbon Lining to Extract Valuable Components for Cryolite Production." Solid State Phenomena 316 (April 2021): 667–72. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.667.

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The technique of mathematical modeling using the Selector software package has been applied to study the leaching of fluorine from the carbon part of the aluminum electrolysis cell spent lining. Based on the model obtained, the effects of the solvent (caustic soda Na2Oку) concentration and the ratio of liquid and solid phases in the pulp on the fluorine extraction have been assessed. The research object was the lining samples by the RUSAL Krasnoyarsk JSC. A thermodynamic assessment of the spent carbon lining components behavior during the alkaline processing has been performed with the introduction of three solvent concentrations into the model: 12.5, 17.5, and 25.0 g/dm3. According to the model solutions, the maximum fluorine extraction (up to 90 %) is achieved when using a reagent with the Na2Oку concentrations of 12.5 and 17.5 g/dm3 and a liquid to solid ratio of 8.5÷10:1. Using the model, the phase composition of the cake and the forms, in which fluorine remains in the solid residue (cake), have been determined. Laboratory studies confirm the convergence of the simulation results with the experimental data: solutions have been obtained to crystallize out cryolite (with fluorine and silica content of 50–53 % wt. and 0.11÷0.53 % wt., respectively), which is in demand in the electrolysis of cryolite-alumina melts.

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18

Dizer, Oleg A., Denis A. Rogozhnikov, and Stanislav S. Naboichenko. "Thermodynamics of Copper Arsenious Raw Materials Dissolution in Nitric Acid." Solid State Phenomena 316 (April 2021): 678–83. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.678.

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This article describes thermodynamic study of hydrometallurgical method for processing of copper arsenious gold-containing raw material. Chemical and phase composition of the material were researched. Calculations of the Gibbs energy change were conducted for possible reactions of the main minerals, present in the raw material, with nitric acid. Eh-pH diagrams and solid/liquid equilibrium distribution diagrams, which were constructed in order to confirm the possibility of obtaining the required reaction products through nitric acid leaching of the studied raw material.

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19

Agapova, L. Ya, S. K. Kilibayeva, and A. N. Zagorodnyaya. "Electrochemical Processing of Metal Wastes of Rhenium-Containing Heat-Resistant Nickel Alloys." Solid State Phenomena 316 (April 2021): 631–36. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.631.

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The paper presents the results of studies of electrochemical processing of large pieces of metal wastes of rhenium-containing heat-resistant nickel alloys (HRNA) with subsequent processing of the products of electrolysis. It shows the possibility of electrochemical processing of large (up to 2 kg) scrap pieces, without preliminary grinding, in sulfuric acid solution with nitric acid addition, under the current density of 500-1000 A/m2, with a temperature of 30-40о С. Up to 80-90% of rhenium and over 90% of nickel, cobalt, chrome and aluminum can be converted into the solution. Tungsten, tantalum and hafnium remain in the anode slime almost completely. Rhenium, nickel and cobalt remaining in the anode slime can be transferred to the solution, when the slime is chemically processed in sulfuric acid solution with nitric acid addition. The cake remaining after chemical decomposition of anode slimes represents a concentrate of refractory rare metals, containing up to 42% W; 18% Ta; 4% Hf. Rhenium is extracted from the combined solutions from anodic decomposition of HRNA wastes, and chemical dissolution of anode slimes, by the known extraction method in the form of the crude ammonium perrhenate (68,9 mас. % Re). After rhenium extraction the raffinate contains considerable quantities of nickel and cobalt, which can be precipitated by the alkali solution in the form of hydroxides to the nickel-cobalt concentrate, containing 31.5% Ni and 4.8% Co.

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20

Karshigina, Zaure B., Zinesh S. Abisheva, and Yelena G. Bochevskaya. "Processing of Hydro-Mineral Lithium Raw Material of Kazakhstan Using Inorganic Sorbents." Solid State Phenomena 316 (April 2021): 643–48. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.643.

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The article presents the results of studies on recovery of lithium from reservoir brines using both commercial and synthesized aluminum hydroxide and hydrated manganese oxide as sorbents. The research results showed that, when using commercial aluminum hydroxide and synthesized hydrated manganese oxide as sorbents, lithium recovery from brine was 21.8 and 20.1%, respectively. Studies were conducted on lithium chemisorption on freshly precipitated aluminum hydroxide, which was obtained by adding aluminum chloride solution and tri-calcium hydro-aluminate to the brine. Chemisorption of lithium was carried out under the following conditions: T = 50 °C; AlCl3 solution concentration - 120 g/dm3; molar ratio Li/Al = 7; pH equal = 8.0-8.8; holding time with stirring 1 h. The degree of lithium extraction from brine was 71%; lithium capacity of freshly precipitated Al (OH)3 was 5.9 mg/g. During calcareous leaching of lithium-aluminum precipitate, lithium was extracted into a solution by 74.7%.

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21

Bochevskaya, Yelena G., Zaure B. Karshigina, and Aynash S. Sharipova. "Processing Technogenic Raw Materials-Phosphorus Slags with the Production of Precipitated Nanosilica and Simultaneous Recovery of Valuable Components." Solid State Phenomena 316 (April 2021): 637–42. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.637.

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The paper provides a flow sheet of the phosphorus slag processing to produce precipitated silica (white soot). The process conditions for opening phosphorus slag at the I stage of leaching have been selected: the nitric acid concentration is 3.5 mol/dm3; the ratio S:L = 1:3.5; the temperature is 60 oС; and the process duration is 1 hour. The parameters of the white soot production II stage have been determined: the HNO3 concentration is 6.5 mol/dm3; the ratio S:L = 1:3.5; the temperature is 50 oС; and the process duration is 1 hour. The temperature effect on the white soot structure and the specific surface have been established. At optimal process parameters, the white soot batches have been obtained with the main SiO2 component content of 88.2 and 90.5 %, and a specific surface of 170 and 182 m2/g, respectively. The through recovery of silicon into a commercial product is 98.0 % of its initial content in slag.

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22

Luo, Yu Jun, and Zhong Yong Gao. "Estimation of Friction Coefficient Related to Squeal in Cutting." Advanced Materials Research 314-316 (August 2011): 603–8. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.603.

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This research focus on the squeals occurred in cutting from the views of tribology. A multi-degree-freedom model was established referring to cylindrical turning. The model was made up of two coupled subsystems — tool and workpiece which coupled through the friction between their contacted surface. The relationship between cutting squeal and friction was studied through experiments, and the coefficients of friction were estimated by experimental data. Then the tribological conditions related to squeal generating were discussed. In the end a method of reducing cutting squeal by lubrication was proposed.

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23

Zhang, Guo Zhi, and Jun Jing Fu. "Study on Mechanical Mechanism of ARB Process Based on Randomness." Advanced Materials Research 314-316 (August 2011): 609–13. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.609.

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The process control mechanism of ARB(accumulative roll bonding) process was studied. Based on micro-plastic theory, the principal stress method of macro-plastic theory and probability theory, theoretical models of rolling force and its standard deviation calculation were established. Moreover, shear deformation was analyzed with the finite element method and the finite element model established was verified through comparing with the experiment. Furthermore, through calculating the rolling force of ARB process of the typical parameters, roll force variation of every cycle was obtained and the theoretical model was verified through comparing with the results of the finite element method. The study in the paper provides analysis method and theory foundation for process control and manufacturing of ARB process.

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Yao, Zhi Hui, Liang Gao, Mi Xiao, and Lei Yang. "DOE-Based Numerical Investigation on Factors Affecting Temperature Field during Line Heating." Advanced Materials Research 314-316 (August 2011): 620–25. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.620.

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Line heating is a complex thermal-mechanical process as many factors affect the final shape of a processed plate. Generally, the temperature field of the processed plate determines the stress field and strain field. To predict the deformation of the processed plate, this paper investigates the effects of different factors on the temperature field during line heating by using design of experiment (DOE). Firstly, a three dimensional thermal elasto-plastic finite element method (FEM) is developed to calculate the temperature field induced by the single-pass oxygen-acetylene line heating. Secondly, the temperature field is analyzed by using fractional factorial design, in which the maximum temperature is selected as the response, and a fishbone diagram is used to overview all influencing factors. After performing a series of numerical experiments selected by using an ortho-gonal array, three main influencing factors are screened out: plate thickness, flow of acetylene and velocity of heat source. Next, the main effects of these factors are discussed. Finally, analytical re-sults indicate that there exist interaction effects among the three main influencing factors. This in-vestigation demonstrates that DOE is an efficient method for study of the temperature field during line heating.

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Shuai, Ci Jun, Pei Feng, Cheng De Gao, Ying Zhou, and Shu Ping Peng. "Simulation of Temperature Field during the Laser Sintering Process of Nano-Hydroxyapatite Powder." Advanced Materials Research 314-316 (August 2011): 626–29. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.626.

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A three-dimensional finite element model has been created to study the change rules of temperature field during the laser sintering process of nano-hydroxyapatite powder. The numerical simulation of temperature distribution has been achieved based on the equivalence between the sintering time and the sintering speed. The simulation results show that the temperature declines gradually along the radial direction of the laser spot. At the same time, there was the largest temperature gradient at the edge of the laser spot. The temperature of sintering layer rises with the increase of laser power linearly when the other process parameters are the same. The maximum sintering temperature is 1320°C with laser power of 8.75W, laser spot diameter of 4mm, sintering time of 5s and layer thickness of 0.2mm. The test results verify that nano-hydroxyapatite powder could be sintered under this process condition. It shows that the finite element model can be used to simulate the temperature field during the laser sintering process.

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Dong, Yi Wei, Ding Hua Zhang, Kun Bu, and Yang Qing Dou. "An Optimum-Curved Die-Profile for Investment Casting of Turbo Blades." Advanced Materials Research 314-316 (August 2011): 630–33. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.630.

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In order to avoid tremendous modifications of the die cavity for investment casting of turbo blades, this paper proposed an inverse iterative compensation method that adjusts certain geometric parameters to establish the die-profile. The parameterized modeling is achieved by identifying geometric parameters describing the mean camber line; the optimum-curve die-profile can be obtained based on the inverse iteration algorithm. As a result, the dimension precision of turbo blades can be guaranteed. The applicability of this method is validated using numerical simulation data.

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Cai, Jun Feng, Jian Zheng Yi, and Tian Peng Li. "The Research of Shock Wave Attenuation Test of UHMWPE-PUF Composite by PVDF Piezoelectric Sensor." Advanced Materials Research 314-316 (August 2011): 639–42. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.639.

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In the paper, The PVDF piezoelectric sensor was customized and the structure and test circuit of PVDF piezoelectric sensor is introduced. The polyurethane(PUF) reinforced by ultra high molecular weigh polyethylene (UHMWPE) material(UHMWPE-PUF composites) was synthesized. The pressure in UHMWPE-PUF composites under explosion load was measured and shock wave attenuation waveform is gained and the data is analyzed. The studies showed that PVDF piezoelectric firm sensor is suitable to shock wave measurement in material and UHMWPE- PUF composites can improve maximally shock wave attenuation properties of the material and have good applied outlook in the realm of anti-explosion.

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Yin, Fei, Hua Jie Mao, Lin Hua, and Zhi Qiang Gu. "Investigation of Die Wear during Fine-Blanking Process of a Kind of Automobile Synchronizer Slipper by FEM and Experiments." Advanced Materials Research 314-316 (August 2011): 643–52. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.643.

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In this paper, die wear during fine-blanking process of a kind of automobile synchronizer slipper was investigated based on Finite Element Method (FEM) and experiments. The Finite Element (FE) model to simulate the fine-blanking process of the automobile synchronizer slipper was established on the DEFORM-3D software platform, and Archard's wear model was employed to calculate die wear during the process. Meanwhile, mesh refinement and automatic remeshing technique were used during meshing process of the blanked materials and bottom die in order to achieve high accuracy results of FE simulations and improve the computational efficiency. Simulation results have been verified and show good agreement with the real manufacture. In addition, relationships between die wear and the process parameters during fine-blanking process such as pressure pad force, ejector force, blanking speed, blanking clearance, fillet radius of bottom die as well as hardness of bottom die were investigated, respectively via FEM. The simulation results indicate that die wear is in proportion to the pressure pad force, ejector force, blanking speed and fillet radius of bottom die, while in inverse proportion to the blanking clearance and hardness of bottom die, which will provide a reliable reference for the real manufacture and engineering application.

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Wen, Li Zhi, Zhi Wei Guan, Jian Feng Song, and Yue Chen. "Finite Element Analysis of Vehicle Engine Connection Rod under Mechanical Load." Advanced Materials Research 314-316 (August 2011): 653–56. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.653.

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In this paper, the model of the engine connection rod is founded by use of UG, and then joined in the ANSYS, applied the Multiphysics module and static structuer analysis function, we can count the stress field of the connection rod and accomplish the evaluate of the mechanical load.

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Chen, Jian Min, Meng Zhang, and Jia Deng. "Optimal Design of Triangle Fastening Screw Thread's Turn Number." Advanced Materials Research 314-316 (August 2011): 657–60. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.657.

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The paper firstly numerically simulates the coupled model of triangle fastening screw threads in the application of ANSYS software. Calculate stress intensity of the screw thread on the axial pressure of 200MPa. The fittest coupled turn number of the screw nut is designed to make sure the strength of coupled teeth and make every turn of the screw thread go on very well and also save material. The maximum equivalent stress of the screw thread changes linearly with the axial pressure. The stress of the thread's root is greater than that of the thread's top so that the root is easily damaged. The paper's research method can apply to the optimal design of the other patterns of screw thread's turn number.

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Tian, Xin Li, Ke Ling Lin, Bao Guo Zhang, and Chun Fang Xue. "Numerical Simulation of Temperature Field and Experimental Verification during Micro-Detonation of Arc Strike Machining." Advanced Materials Research 314-316 (August 2011): 661–66. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.661.

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A theoretical model of heat transfer for Si3N4 ceramics during micro-detonation of arc strike machining was established. Based on finite element theory, the temperature of Si3N4 ceramics during micro-detonation of arc strike machining was simulated with the aid of COMSOL Multiphysics software, combined with the actual processing, the width and depth of crater impacted by micro-detonation were calculated. The simulation results show that the highest temperature of Si3N4 ceramics is over 12100 °C in a given processing parameters, while the high-temperature zone is quite small; the material removal rate with the increase of pulse width and electricity increases, with the increase of the nozzle radius first increases and then decreases; the diameter to depth ratio with the increase of pulse width and electricity decreases, with the increase of nozzle radius increases. The data gained from the simulation is proved to be accordant with the data gained from experiments.

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Deng, Kang. "A New Single Step Full Discrete Scheme for a Semilinear Second Order Hyperbolic Equation." Advanced Materials Research 314-316 (August 2011): 667–71. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.667.

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In this paper, we study a simplified single step full discrete scheme for a class of semilinear hyperbolic problems of second order. At first we obtain a system of second ordinary differential equations with initial value by use of spatially discrete finite element approximation with interpolated coefficients. Next in terms of a single step scheme to the time variable for this system we gain a fully discrete scheme with high accuracy. Finally we give the stable and convergence of the full discrete schemes.

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Liu, Yi, and Ji Shun Li. "Finite Element Analysis of High - Pressure Grinding Mill." Advanced Materials Research 314-316 (August 2011): 675–81. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.675.

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The stress distribution of the high - pressure grinding roller is an important index of the grinding mill design. A simulation model of high - pressure grinding roller is created by means of finite element method (FEM), utilizing the FEM software ANSYS. At first, the paper calculated the pressure of the high - pressure grinding roller by the grinding materiel mathematical model. Secondly, a physical model is set up material characteristics is defined and the areas are meshed, then the border conditions are established, finally loading and solving are made. The result of the FEM simulation indicated the mathematical model of the grinding materiel is rational.

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Du, Jian Jun, Wing Bun Lee, Chi Fai Cheung, Suet To, Ying Xue Yao, Dong Gao, and Jian Guang Li. "Research on Software Error Compensation of Ultra-Precision Lathe." Key Engineering Materials 315-316 (July 2006): 602–6. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.602.

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Based on the theory of kinematics for multi-body system, the relative motion constraint equation is deduced according to the structure layout and the error distribution of the ultra-precision lathe Nanoform200. By solving the constraint equation, the corrective NC code is derived that can compensate the geometric errors. The error compensation software is developed aimed at the ultra precision manufacturing of optics parts. The cutting experiments show that the method and model in this paper can improve the accuracy about 50% for the ultra-precision turning of optical parts.

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Zhou, Jian Zhong, Yong Kang Zhang, Xing Quan Zhang, Chao Jun Yang, Hui Xia Liu, and Ji Chang Yang. "The Mechanism and Experimental Study on Laser Peen Forming of Sheet Metal." Key Engineering Materials 315-316 (July 2006): 607–11. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.607.

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Laser peen forming of sheet metal is a new plastic forming technique based on laser shock waves, which derives from the combination of laser shock processing and conventional shot peening technique, it uses high-power pulsed laser replacing the tiny balls to peen the surface of sheet metal, when the laser induced peak pressure of shock waves exceeds the dynamic yield strength of the materials, the sheet metal yields, resulting in an inhomogeneous residual stresses distribution in depth. The sheet metal responds to this residual stress by elongating at the peened surface and effectively bending the overall shape. On the basis of analyzing the mechanism of laser peen forming, the line-track-peening experiments of 45 steel sheets with 2 mm thickness were carried out; a curved sheet metal with deep layer of residual compressive stress was obtained. The preliminary experiment result shows that laser peen forming can offer desirable characteristics in shaped metals and is a valuable technique for producing components for a range of industries.

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Wei, P., Z. L. Wang, and L. H. Qiu. "A New Fuzzy Variable Structure Control of a Type of Nonlinear Multivariable System." Key Engineering Materials 315-316 (July 2006): 623–27. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.623.

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In order to improve the robust performance for a type of nonlinear multivariable system, a new fuzzy variable structure control method is introduced in detail, which combined the features of traditional variable structure control method with the advantages of the fuzzy control theory. The present work realized the linearization of the nonlinear multivariable system, and then the new fuzzy variable structure control method is applied to control the linearization system. The robust experiments were carried out on the novel method. The results indicated that the required robust performance could be achieved with high efficiency by utilizing the new method.

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Liang, Yu Teng, C. J. Lo, and W. C. Chen. "The Image Similarity Analysis Technique Applied to the Tool Wear Monitoring in Face Milling." Key Engineering Materials 315-316 (July 2006): 628–31. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.628.

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The purpose of this paper is to monitor the tool wear based on the image data of cutting tool in the face milling operation. The surface images of the different coated inserted blade cutters are captured using a machine vision system incorporating with the mutual information and image similarity analysis technique for processing the images. The milling test is designed by using Taguchi’s method. The experimental results indicate that the coating layer factor is recognized to make the most significant contribution to the over all performance. The TiAlN-surface multilayer coated inserted blade cutter has the least wear rate amongst these coated milling cutters and has the longest tool life in this experiment.

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Xu, Chong Hai, Chuan Zhen Huang, Xing Ai, and H. Y. Wang. "Thermal Shock Resistance of a New Ceramic Tool Material and Its Microstructural Characterization." Key Engineering Materials 315-316 (July 2006): 632–36. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.632.

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Thermal shock resistance is one of the important properties for ceramic cutting tool materials in machining operation. Thermal shock resistance of a new SiC/Ti(C,N)/Al2O3 ceramic tool material is investigated in detail by means of the water quenching test. It indicates that the addition of Ti(C,N) and SiC is effective in the improvement of thermal shock resistance of the composite and the tested maximum temperature difference of thermal shock reaches about 330. Microstructures of the ceramic samples after thermal shock have been observed and analyzed by SEM focusing mainly on the morphologies of cracks and the peeling off of grains as well as the accompanied oxidation phenomenon at elevated temperatures.

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Liu, Li Li, Jian Xin Deng, and Jun Zhou. "Erosion Wear and Design Model of Functionally Gradient Ceramic AJM Nozzle." Key Engineering Materials 315-316 (July 2006): 637–40. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.637.

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The stress states of the ceramic nozzle in abrasive jet machining (AJM) process are analyzed. Results shown that the maximum stress appears in entrance area of the nozzle and minimum stress in middle area, while the stress of exit area was lower than entrance area and higher than middle area. It can interprets why the entrance and exit area of the nozzle were worn badly. The idea of functionally gradient material (FGM) theory was used to design of ceramic nozzle. The purpose was to reduce the stresses at the entrance and exit area of the nozzle during AJM processes. The physical, composition distribution, and property parameter models of the FGM nozzle were established.

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Xu, Feng, Dun Wen Zuo, Wen Zhuang Lu, Xiang Feng Li, Bing Kun Xiang, and Min Wang. "Preparation of Nanocrystalline Diamond Films on Molybdenum Substrate by Double Bias Method." Key Engineering Materials 315-316 (July 2006): 646–50. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.646.

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The synthesis of nanocrystalline diamond film on polycrystalline molybdenum substrates was carried out by using of self-made hot filament chemical vapor deposited (HFCVD) system. Positive bias voltage on the grid electrode on top of hot filaments and negative bias voltage on the substrate were applied. High purity and extremely smooth nanocrystalline diamond films were successfully prepared by using the double bias method. Raman, SEM, XRD and AFM results show that the diamond films obtained have grain sizes less than 20nm, nucleation density higher than 1011cm-1. The mechanism of double bias is also discussed in this paper. The positive grid bias increases the active, decomposition and ionization of hydrogen and methane molecules, while negative substrate bias helps positive carbon-containing ions bombard the substrate that leads to the high nucleation density of the diamond film.

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Yu, Tian Biao, Ya Dong Gong, Jie Liu, G. Yu, and Wan Shan Wang. "Study on Networked Technical Service System Oriented Production Process." Key Engineering Materials 315-316 (July 2006): 651–55. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.651.

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To improve the quality and efficiency of technical service, shorten the producing cycle of product, a new mode of technical service is presented, which is networked technical service based on the multi-Agent technique, network technique and modern communications technique. The architecture and function of the networked technical service system oriented production-NTSS are researched, and the key technologies including multi-Agent system, virtual assembling oriented the process of production and the assignment and rank of technical service information are studied. The workflow of NTSS is discussed, and base on these theories a prototype system is established, and the security, practicability and high efficiency of NTSS are proved.

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42

Zhang, Song, Xing Ai, Jun Zhao, and J. G. Liu. "Effects of Dynamic Characteristics of High-Speed Machine Tool/Cutting Tool System on Machining Quality." Key Engineering Materials 315-316 (July 2006): 656–60. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.656.

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During high-speed machining, in order to make cutting tools work reliably and obtain ideal machining quality, not only good static characteristics, but also good dynamic characteristics are necessary. In this paper, with the help of the close combination of experimental research and modal parameter identification technique, the dynamic characteristics of the machine tool/cutting tool system were analyzed. Experimental results indicated that studying the effect of the dynamic characteristics on cutting force, machining accuracy and surface roughness could provide theoretical basis for effectively excluding the resonance zone that obviously destroyed machining quality and then optimizing cutting parameters further.

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Yao, C. Y., Wei Peng, and Tao Gao. "The Abrasion Mechanism of Diamond Coated Blades with Ultraviolet-Cured Resins." Key Engineering Materials 315-316 (July 2006): 661–65. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.661.

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In recent work, a creative idea has been proposed by applying the rapid prototyping technology to develop a new diamond-coated blade based on ultraviolet-cured resin bond. The new technology features many advantages such as fast processing speed, low environmental pollution, and low energy consuming. This paper makes an investigation on the adherence and abrasion mechanisms of such diamond blades. The experimental plan is well designed for selection of an optimal prescription of the mixture to achieve good mechanical performance and a manufacturing process is proposed to produce ultraviolet-cured resin bonded diamond coated blades. Practical experiments are carried to test the blade performance and to compare with different tools in incising artificial crystal. Furthermore, this paper also observes how the tensile strength and elastic modulus of ultraviolet-cured resin affect the crevasse and quality of machined edge surfaces.

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Wan, Zhen Ping, Yong Tang, and F. Y. Zhang. "On Manufacturing of Long Stainless Steel Fiber with Fin by Multi-Tooth Tool and Mechanical Properties of the Fiber." Key Engineering Materials 315-316 (July 2006): 666–70. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.666.

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Metal fiber manufactured by the methods nowadays available almost could not meet the new requirements any more due to the increasing demands for its properties as it is used more and more widely. In this paper, cutting by multi-tooth tool, a new method, which can bifurcate chip and simultaneously get many pieces of long stainless steel fiber with high tensile strength, good tenacity and corresponding diameter within 100μm even 50μm, is proposed. Tiny fins which induce crystal growth as nucleation in composites can form regularly at the edge of fiber under certain conditions. The fiber possesses unique advantages if it is used to filled, reinforced and porous materials because of its rough surface, fins, high tensile strength and good tenacity.

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Jiang, J., Yong Bo Wu, Xu Yue Wang, and M. Kato. "A New Magnetic Polishing Liquid (MPL) for Precision Surface Finishing." Key Engineering Materials 315-316 (July 2006): 671–75. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.671.

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This paper presents a new magnetic polishing liquid (MPL) produced by mixing sub-micron or micron order abrasive particles into a magnetic compound fluid (MCF) and its fundamental performance in surface finishing. MCF is an intelligent fluid, which is developed by mixing a magnetic fluid (MF) and a Magneto-rheological fluid (MRF) into a solvent, and hence reacting upon magnetic fields. In the present work, seven kinds of kerosene-based MPLs were prepared. The hydrodynamic characteristics of MPLs such as the viscosities under different magnetic fields were investigated. The obtained result indicated that the viscosity increases with the growing of the magnetic field and that the type of MPL affects greatly the viscosity. This phenomenon was discussed by observing the magnetic clusters formed in MPL. It was observed that the magnetic clusters are distributed along the magnetic fluxes. An experimental result indicated that the surface roughness varies with polishing time and gets smallest at a certain value of magnetic field strength.

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Iqbal, Asif, Ning He, Liang Li, W. W. Zha, and Y. Xia. "Influence of Tooling Parameters in High-Speed Milling of Hardened Steels." Key Engineering Materials 315-316 (July 2006): 676–80. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.676.

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Tool life, surface roughness, and cutting forces have always remained extremely important output parameters of milling process. In this paper an attempt has been presented in order to study the influence of cutter geometry and cutter coating upon these three output parameters. Series of high-speed side milling experiments were done upon hardened AISI 4340 and AISI D2 steels using coated and uncoated carbide cutters. Mechanisms of wear occurring in different tools have been described in the paper using SEM photographs and micro-analysis of the tool surface. The analysis of experimental data shows that the coated carbide cutters having high values of helix angle and small values of rake angle, in the negative range, provide the better optimization of highspeed milling of hardened steels. Results imply that tool geometry and coating are influential upon cutting forces and tool wear but not upon surface quality. Introduction of MQL in the process leads the tool to fail abruptly because of the onset of chipping.

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Silitonga, Pola Risda Aswita, Wilis Ari Setyati, and Mada Triandala Sibero. "Pengaruh Fermentasi Gracilaria verrucosa dengan Penambahan Starter Lactobacillus plantarum pada Profil Metabolit dan Aktivitas Biologisnya." Journal of Marine Research 11, no. 2 (April 30, 2022): 309–19. http://dx.doi.org/10.14710/jmr.v11i2.33262.

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Gracilaria verrucosa merupakan salah satu spesies penting Rhodophyta yang telah banyak dimanfaatkan dalam berbagai industri. Hasil penelitian sebelumnya menunjukkan bahwa G. verrucosa memiliki aktivitas biologis sebagai antioksidan, namun laporan mengenai potensi sebagai antibakteri dan antikanker masih sedikit dilaporkan. Penelitian ini bertujuan untuk mengetahui pengaruh fermentasi menggunakan L. plantarum terhadap aktivitas antibakteri, toksisitas, dan karakteristik metabolit ekstrak rumput laut G. verrucosa dengan waktu fermentasi yang berbeda. Metode dalam penelitian ini adalah preparasi, fermentasi, ekstraksi, uji antibakteri, uji toksisitas, dan karakterisasi metabolit. Uji aktivitas antibakteri dengan metode agar well diffusion terhadap bakteri foodborne disease sedangkan uji toksisitas dengan metode BSLT. Karakterisasi metabolit dilakukan menggunakan KLT dengan eluent kloroform: etil asetat (9:1), serta visualisasi metabolit dengan reagen Dragendorff, dan Ninhidrin. Hasil analisis KLT menunjukkan ekstrak G. verrucosa yang difermentasi menggunakan L. plantarum menghasilkan senyawa yang diduga senyawa alkaloid dan asam amino bebas. Uji aktivitas antibakteri ekstrak G. verrucosa menunjukkan hasil negatif dan tidak memiliki aktivitas antibakteri terhadap bakteri MDR E. coli dan S. typhi. Analisis toksisitas menunjukkan bahwa setiap ekstrak rumput laut dikategorikan toksik terhadap larva A. salina L. dengan nilai LC50 ETA (73,26 μg/mL), EDA (218,09 μg/mL), Fr 24 (316,69 μg/mL), Fr 48 (316,69 μg/mL), dan Fr 72 (316,69 μg/mL). Berdasarkan hasil penelitian menunjukkan bahwa fermentasi menggunakan L. plantarum tidak dapat meningkatkan aktivitas biologis rumput laut G. verrucosa. Gracilaria verrucosa is one of the most important Rhodophyta species that has been widely used in various industries. The results of previous studies showed that G. verrucosa has a weak antioxidant activity, however, reports on its potential as antibacterial and anticancer are still under explored. This study aimed to determine the effect of fermentation using L. plantarum in G. verrucosa’s metabolites and biological activities with different fermentation times. This study consisted of preparation, fermentation, extraction, antibacterial test, toxicity test, and metabolite characterization. The antibacterial activity assay was conducted by agar well diffusion method against foodborne disease bacteria while toxicity test using BSLT method. Metabolite characterization was carried out using TLC with chloroform : ethyl acetate (9:1) as the eluent, spot visualization was conducted by the addition of Dragendorff, and Ninhydrin reagents. The result of TLC analysis showed that G. verrucosa produced alkaloids and amino acids derivative compounds after fermentation. G. verrucosa extracts had no antibacterial activity against MDR E. coli and S. typhi. Toxicity assay showed that each seaweed extract was categorized as toxic to A. salina L. larvae with an LC50value of ETA (73.26 ug/mL), EDA (218.09 ug/mL), Fr 24 (316.69 ug/mL), Fr 48 (316.69 ug/mL), and Fr 72 (316.69 ug/mL). Based on the results of the study showed that fermentation using L. plantarum could not elevate the antimicrobial and toxicity of G. verrucosa.

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Yu, Ying Xia, Bo Lin He, Huang Huang Yu, and Jian Ping Shi. "Research about the Effect of Residual Stress on the Fatigue Life of Cruciform Joint of 16MnR Steel." Advanced Materials Research 382 (November 2011): 400–403. http://dx.doi.org/10.4028/www.scientific.net/amr.382.400.

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Surface treatment was carried out on the cruciform joint of 16MnR steel by using the HJ-II-type ultrasonic impact machine. The impact current is 1.2A, impact amplitude is 30 microns. Fatigue experiments were carried out for impact treated specimen, impact treated and heattreated specimen and un-heattreated specimen. The effect of ultrasonic impact on the hardness of the weldment and weld toe was researched. The experimental results show that the fatigue life of the cruciform joint of 16MnR steel can be significantly improved through the ultrasonic impact treatment and the hardness of weld toe can also be promoted. Compared to the sample without impact treatment, its fatigue life was increased 692.52%. The hardness of weld toe was increased 31%. Compared to the sample with heat treatment, the fatigue life of impact specimen was increased 316.67%. Compared to the sample without impact treatment, the fatigue life of impact and heat treated specimen was increased 218.69%.

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Ali, Mazen Nasser. "تأثير وزن الكتكوت بعمر يوم واحد على صفات النمو وقطعيات الذبيحة لفروج اللحم ROSS." Electronic Journal of University of Aden for Basic and Applied Sciences 2, no. 4 (December 31, 2021): 186–89. http://dx.doi.org/10.47372/ejua-ba.2021.4.127.

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أجريت التجربة في حظيرة قسم الانتاج الحيواني كلية ناصر للعلوم الزراعية م/ لحج خلال الفترة 28/1/2020 لغاية 2/3/2020م، استهدفت الدراسة دراسة فئتين وزنيتين للكتاكيت، استخدم في التجربة 90 كتكوت من سلالة Ross بعمر يوم واحد غير مجنس قسمت هذه الكتاكيت إلى معاملتين على أساس الوزن المعاملة الاولى T1 45 كتكوت بوزن 39-40جم واحتوت المعاملة الثانية T2 أيضا على 45 كتكوت بوزن 44-45جم قسمت الكتاكييت في المجموعتين اى ثلاثة مكررات بوقع 15 كتكوت لكل مكرر، أظهرت النتائج وجود تفوق معنوي عند مستوى (P<0.05) في صفتي وزن الجسم ووزن الذبيحة حيث تفوقت المعاملة T2 على المعاملة T1 و كانت الأوزان 1576.66 و 1126.جم و 1643.33، 1193.33 جم لكلا من وزن الجسم ووزن الذبيحة على التوالي في حين لم تظهر النتائج اي تفوق معنوي في كمية العلف المستهلك ومعامل التحويل الغذائي ونسبة التصافي. اظهرت المعاملة T2 تفوقا وزنيا على المعاملة T1 في وزن الصدر، الأفخاذ الظهر والرقبة وكانت الاوزان 391، 310، 203.33، 78 جم و 433، 316.67، 8، 225، 86.67 جم، للمعاملة T1 و T2 على التوالي، وهذه الزيادة لم تصل حد المعنوية.

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Liu, Yi, Weina Li, Changhong Tan, Xi Liu, Xin Wang, Yuejiang Gui, Lu Qin, Fen Deng, Changlin Hu, and Lifen Chen. "Meta-analysis comparing deep brain stimulation of the globus pallidus and subthalamic nucleus to treat advanced Parkinson disease." Journal of Neurosurgery 121, no. 3 (September 2014): 709–18. http://dx.doi.org/10.3171/2014.4.jns131711.

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Object Deep brain stimulation (DBS) is the surgical procedure of choice for patients with advanced Parkinson disease (PD). The globus pallidus internus (GPi) and the subthalamic nucleus (STN) are commonly targeted by this procedure. The purpose of this meta-analysis was to compare the efficacy of DBS in each region. Methods MEDLINE/PubMed, EMBASE, Web of Knowledge, and the Cochrane Library were searched for English-language studies published before April 2013. Results of studies investigating the efficacy and clinical outcomes of DBS of the GPi and STN for PD were analyzed. Results Six eligible trials containing a total of 563 patients were included in the analysis. Deep brain stimulation of the GPi or STN equally improved motor function, measured by the Unified Parkinson's Disease Rating Scale Section III (UPDRSIII) (motor section, for patients in on- and off-medication phases), within 1 year postsurgery. The change score for the on-medication phase was 0.68 (95% CI – 2.12 to 3.47, p > 0.05; 5 studies, 518 patients) and for the off-medication phase was 1.83 (95% CI – 3.12 to 6.77, p > 0.05; 5 studies, 518 patients). The UPDRS Section II (activities of daily living) scores for patients on medication improved equally in both DBS groups (p = 0.97). STN DBS allowed medication dosages to be reduced more than GPi DBS (95% CI 129.27–316.64, p < 0.00001; 5 studies, 540 patients). Psychiatric symptoms, measured by Beck Depression Inventory, 2nd edition scores, showed greater improvement from baseline after GPi DBS than after STN DBS (standardized mean difference −2.28, 95% CI −3.73 to −0.84, p = 0.002; 3 studies, 382 patients). Conclusions GPi and STN DBS improve motor function and activities of daily living for PD patients. Differences in therapeutic efficacy for PD were not observed between the 2 procedures. STN DBS allowed greater reduction in medication for patients, whereas GPi DBS provided greater relief from psychiatric symptoms. An understanding of other symptomatic aspects of targeting each region and long-term observations on therapeutic effects are needed.

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