bluuebunny/crossref_metadata_2025 huggingface dataset:
Breeding of Oleaginous Rhodotorula Glutinis and the Synthesis of Biodiesel
Authors: He Ping , Huang Jia Le , Shi Qing Cui , Li Xiao Lin , Yuan Li , Zou Qian Ru
Published: October 2011

Biodiesel is a renewable, easily biodegradable energy. However, due to the rising cost of its raw materials such as vegetable oils, using of biodiesel is restricted. Microbial lipid has many advantages like short production cycle, high production efficiency, and low cost, can be used to provide cheap and ample raw materials for biodiesel production. In this study, Rhodotorula glutinis was treated with ultraviolet radiation to get mutants and then screened by spectrophotometry. RG-UV02 was identified as a high yield oleaginous strain and exhibited a good genetic stability. Optimal fermentation conditions were obtained as follows: 20% dissolved oxygen, 10% inoculum size, 100 g/L glucose and C/N ratio was 154. Under such conditions, dry biomass, lipid concentration and lipid content of RG-UV02 reached 11.583 g/L, 3.535 g/L and 30.51%，respectively, which raised by 10.77%, 36.86% and 23.52% than these before optimizing. Gas chromatography-mass spectroscopy analysis showed that the compositions of RG-UV02 lipid were similar to these of vegetable oils. Chemical modification improved the affinity of the porcine pancreatic lipase with the substrate. The enzyme activity recovery rate of immobilized chemical modification porcine pancreatic lipase was 47.90%. The calculation result showed that immobilized chemical modification porcine pancreatic lipase catalyzed 1g RG-UV02 lipid to synthesize 183.8 mg biodiesel, the yield rate of transesterification was 35.55%.
Pathway Analysis of the Restrictedly Expressed Genes in Oryza Sativa Implanted by the Low-Energy Nitrogen Ion
Authors: Ya Hui Yuan , Wang Wei Dong , Chen Qiu Fang , Qin Guang Yong , Jiao Zhen , Zhang Xiang Sheng
Published: October 2011

The current knowledge of the transcriptome is limited to understand the exact molecular mechanism of the ion-implantation biological effects on cereals. In order to investigating the overall characteristics of the transcript profiles associated with these puzzling biological effects. We used the Agilent Rice Oligo Microarray （4×44K）Genome Array to learn the molecular mechanism in rice responding to ion-implantation. Rice seeds were implanted by the Nitrogen ion beam and their vigor index was investigated at ten days after germination. Total RNAs was extracted from the rice seedlings at 96 hour after germination and hybridized by the genome genechip. The results of measuring of the vigor index showed that lower-dose implantation of the nitrogen ion beam (6×1017 N+/cm2) promoted the vigor index of the rice seedlings and the higher-dose implantation (9×1017 N+/cm2) damaged the rice seedlings because of the smaller vigor index than the control. The analysis of the genechip array showed that there were 982 transcripts expressed differentially (fold change＞2 and P value＜0.05) including 429 up-regulated transcripts and 553 down-regulated transcripts under the dose3 6×1017 N+/cm2. 30 out of the 553 down-regulated transcripts were involved in 48 pathways. 14 out of these 30 transcripts were associated with more than two interrelated pathways. Os04g0518400 (Phenylalanine ammonia-lyase 2 (PAL; EC 4.3.1.5; down-regulated 3.3 folds; p value=0.005) were involved in 7 pathways, Os07g0446800 (Hexokinase; dwon-regulated 2.8 folds; p value =0.006) were involved in 12 pathways, and Os02g0730000 (Mitochondrial aldehyde dehydrogenase ALDH2a; down-regulated 2.2 folds; p value=0.019) were involved in 13 pathways. These results revealed that down-regulated genes involving important pathways were compatible with the distinct cellular events in response to implantation of low-energy ion beam and supplied the first comprehensive and comparative molecular information for further understanding the mechanism underlying implantation of the low-energy nitrogen ion beam.
Study on Aerobic Biological Phase in the System of Coal Tar Processing Wastewater Treatment
Authors: Lǚ Yan Li , Wang Yan Qiu , Shan Ming Jun , Pan Da Wei , Li Tie Feng , Hu Hong Zhi
Published: October 2011

The paper discusses the change regulation, characteristics and designation function of the aerobic biological phase in the biological treatment system of single reactor system for high ammonium removal over nitrite-anaerobic ammonium oxidation (SHARON-ANAMMOX) of Coal Tar Processing wastewater treatment. And soma advice is given for the adjustment and supervision of the similar biological disposing system of industrial dirty water.
A Dense Deformable Model for Craniofacial Reconstruction
Authors: Hu Yong Li , Sun Yan Feng , Yin Bao Cai , Zhou Ming Quan
Published: October 2011

The traditional craniofacial reconstruction methods construct the face shape according to the soft tissue thickness measured at a sparse set of landmarks on the skull. But the landmarks are difficult to detect and generally need human interactive assistance. The quantity and position of the landmarks lack for uniform definition. We propose an automatic craniofacial reconstruction method based on a dense deformable model. To construct the model, hundreds of skull and face samples are acquired by CT scanner. A dense mesh registration algorithm is proposed to build the point-to-point correspondences of the samples. Based on the aligned samples, the deformable model is constructed. For a given skull, the reconstructed face is obtained by a model matching procedure. Experimental results indicate that the deformable model has good performance for craniofacial reconstruction.
Mx Gene Polymorphism in Part Region of Eight Local Chicken Breeds
Authors: Yin Chun Guang , Cao Ding Guo , Du Li Xin
Published: October 2011

In the study, theMxgene promoter, exon 1, exon 2, and exon 14 and intron 13 in eight Chinese local chicken breeds were examined. Amino acid 631 in the GED region was tested in eight Chinese local chicken breeds and two exotic breeds. The frequency of allele A was 0.1259 and the frequency of allele G was 0.8741. Meanwhile, induction of expression of theMxgene in chicken embryo fibroblasts was analyzed in the local chicken breed, Beijing-you and the exotic breed, White Leghorn.The semi-quantitative and quantitative results showed that the expression of theMxgene in White Leghorn was significantly different under different induction conditions. There was also a difference in the genotypic distribution of S631N in two breeds: allele A/G was 0.8471/0.1529 and 0.1613/0.8387 in White Leghorn and Beijing-you chickens, respectively. We speculate that the difference in the genotypic distribution has an effect onMxgene expression.
Simultaneous Determination of 10-Deacetylbaccatin，Cephalomannine and Taxol in Different Parts of Taxus Media with Different Growth Years by UPLC
Authors: Zhang Jing , Yang Chao Feng , Yuan Ke
Published: October 2011

Taxus media is the natural hybrid variety of Taxus cuspidate and Taxus baccata, and has been used as an anticancer plant with some medical components-taxanes. In this study, ultra performance liquid chromatography was used for quantiﬁcation of three major bioactive taxanes in Taxus media, which were collected in Zhejiang province and Sichuan province (China). As a result of this study, a convenient, accurate, rapid and reproducible UPLC method has been developed to successfully quantify 10-Deacetylbaccatin Ⅲ (10-DABⅢ), Cephalomannine and Taxol in the needle and twig of Taxus media. The results indicate that the sequence of the contents of three active components in Taxus media with different parts was needle>twig; the sequence of the contents of three active components in Taxus media with different growth years was 5 year old >4 year old >3 year old; and there were great differences in the contents of three active components in Taxus media between Zhejiang province and Sichuan province. The results also provided a scientific basis for uses of Taxus media.
License Plate Location Method Based on LOG Edge Detection Operator
Authors: Wu Zhan Wen
Published: October 2011

The license plate location method is the key technology of license plate recognition system, new algorithm is proposed based on LOG operator detecting edge of License Plate Location. First, a large number of color plate images are preprocessed to remove the background interference information, and then rough location of license plate based on block method, search area of plate will be greatly reduced and accurate positioning the plate will be realized by LOG operator combined with projection method. Static license plate image positioning by simulation and analysis show that the method has high accuracy in license plate location.
Talent Training Order Mode Practicing and Exploring on Insurance Claims Professional
Authors: Sun Hui Zhi
Published: October 2011

Abstract. Claim Management is a professional work; Order mode can decrease the demand difference between school and enterprise. There are some problems in this mode, for example, less cognitive aspects of School-enterprise cooperation, and inconformity for common account. The paper analyses the problems of talent training mode of order, and puts forward some improvement measures and suggestions.
Impact Signal Analysis and Fault Diagnosis of High-Speed Automata
Authors: Pan Ming Zhi , Pan Hong Xia , Zhao Run Peng
Published: October 2011

Aiming at the early fault diagnosis of the automata of small-caliber antiaircraft guns, a full set of theories and techniques for the early fault diagnosis of the high-speed automata, based on the techniques of the decomposition of motility patterns and the fusion of information entropy, have been established in this article by the strategy of combining of the theoretical research and the experiment study, which can deal with the practical problems of the superposition and interference of successive impulse signals, cope with the difficulties in the effective extraction of the weak signals of early faults in the environment with strong noises and in the determination of sensitive characteristic parameters, and overcome the disadvantages of the traditional methods of fault diagnosis such as its low conversation speed, the weakness in determining the accurate location of faults and the impotence in real time diagnosis. With the techniques of motility pattern decomposition and information entropy fusion, the efficiency and accuracy of the early fault diagnosis of automata will be increased and the study scope of the mechanical fault diagnosis discipline will be extended.
Finite Element Simulation of Surface Roughness of an Al-5052 Plate Processed by Shot Peening
Authors: Lan Jiao Xia , Wang Mei Li , Wang Yan Hong , Shen Xue Jing
Published: October 2011

The evolution of surface roughness of Al-5052 plate subjected to shot peening was simulated by means of LS-DYNA, and the influences of variation of parameters, such as the size of shot, the velocity of shot, the density of shot, strength coefficient, strain hardening exponent, friction coefficient and incident angle, were investigated. Moreover, the effect of space ratio of two shots was also studied. The simulated results, analytical results and experimental results were compared, and the results showed that the simulated results were agreement with experimental results and analytical results, that the important roles played by the shot size and shot velocity, but to a much lesser extent by the other parameters.
Micro-Structure and Hardness of (Ti,Al,Nb)N Coatings Prepared under Different Negative Pulse Bias by Arc Ion Plating
Authors: Li Ming Sheng , Zhang Shu Juan , Huang Jiao , Zhang Li Zhen
Published: October 2011

In this study, composite metastable (Ti,Al,Nb)N coatings were respectively deposited on a wrought martensite steel 1Cr11Ni2W2MoV by arc ion plating technique with different negative pulse bias. With the increase of negative bias, the deposition rate initially increases and then decreases, metallic composition of the coatings deviates from the target more obviously, grain size is refined and the orientation of B1 phase changes from (111) to (220), and the hardness of the coatings improve first and then drop.
Dynamic Data-Bit Allocation of a Ternary Optical Computer
Authors: Wang Xian Chao , Yao Yun Fei , Wang Chun Sheng , Wang Kang Zhe
Published: October 2011

The purpose of this study is to explore the allocation of lots of data-bit resource in a ternary optical computer (TOC). It analyzes previous important results and proposes the Dynamic Data-bit Allocation (DDBA) method. And it divides 1024 data-bits of TOC into 8 sizes of suanweis by using static grouping technology, and discusses the process of DDBA in detail. Finally, an example is given to illustrate the allocation process.
Effect of Annealing Process and Cold Reduction Ratio on Microstructure and Mechanical Property of 350MPa Grade Structural Hot Dip Galvanized Steel Sheets
Authors: Wang Min Li , Zheng Zhi Wang , Xiao Li
Published: October 2011

Hot rolled 350MPa Grade structural hot dip galvanized steel sheets was used to study the effect of annealing process and cold reduction ratio on the microstructures and mechanical properties. The results showed that the experimental steel was recrystallize finished after cold rolling follow different cold reduction ratio and Salt-bath annealing (annealing temperature 750°C and soaking time 60s) under experimental condition. When the cold reduction ratio was increased, annealing temperature was above 720°C, the yield strength and tension strength had no significant change. The annealing temperature was 750°C,the elongation had no significant change . when the cold reduction ratio was increased,the plastic strain ratio value reduced, and the strain hardening exponent value was gradually increase. In the end, that suggested the optimal annealing temperature is 750°C,and cold reduction ratio is 55% to 65%, consequently that obtained good match of mechanical properties and punching property.
Optical Fiber CO Concentration Measurement Prism of the Gas Chamber Variable Optical Path Automatic Adjustment System Research
Authors: Zhu Hong Xiu , Zheng Hao , Zhang Hong Bo , Wang Xin , Yang Bo Xi , Yang Xiong , Hou Bo
Published: October 2011

According to the absorption spectrum, combined with CO distribution feedback type laser diode (DFB-LD) light source, we selected R a center for 1567.3 nm as the wavelength of the absorption spectrum line. Comprehensively using of prism of gas chamber and harmonic detection technology, we constructed the optical fiber CO concentration measurement system. Through the stepping motor regulation height, it changes indoor prism gas effective absorption process, adjusts the light sensitivity system.
Influence of Depth of Cut on Grind-Hardened Layer and Its Uniformity
Authors: Liu Lian Fen , Zhuang Jie Zhen , Liu Chao
Published: October 2011

The grind-hardening of steel 65Mn had been carried out on a conventional surface grinder with alumina grinding wheel, the influence of depth of cut on the microstructure and the microhardness of workpiece, the depth and its uniformity of grind-hardened layer were studied. The results show that the completely hardened zone of grind-hardened layer is composed of fine acicular martensites, residual austenites and a little carbide. The variety of depth of cut has no obvious influence on the microstructure and the microhardness of completely hardened zone of grind-hardened layer. The maximum depth of grind-hardened layer and the depth uniformity of grind-hardened layer of workpiece increases with the increase of depth of cut ap.
Automatic Wool Washing Machine Design and Research
Authors: Fan Hong Chao , Yi Xin Hua , Cheng Xiao Min , Zhu Ya Fen
Published: October 2011

As import and export business of the wool continues to expand in China, it is necessary to carry out constantly random testing of wool for quality control departments, at the same time it is urgent to use special wool washing machine to monitor the cleaning process of the wool. However, wool cleaning machine still has not been developed in market. The object of washing machine is the wool conglomeration-like dust samples with other impurities. This paper presents the design principle and operational performance analysis of wool washing machine, its design parameters and product quality has been verified to be improved by the experiment testing.
Design and Simulation of Brushless DC Motor Control System Based on DSP
Authors: Zhang Xia , Sun Ren Yun , Liu Xi Ming
Published: October 2011

Based on the principle of sensorless control of brushless DC motor (BLDC) and combining the characteristics of TMS320LF2407A, this paper mainly researched on the key techniques of position detection and starting for sensorless BLDC. And put forward a sensorless BLDC control system, which combined back-EMF and pre-position start mode. The simulation has shown that the control system meets the requirements of stability and rapidity, and it is able to control motor precisely.
Research and Application of High-Efficiency Multi-Cyclone Dust Removal
Authors: Yang Yan Hong , Ni Da Fu
Published: October 2011

Performance and working principle of high-efficiency multi-cyclone were analyzed, and the structural design shortage of original high-efficiency multi-cyclone was pointed out. Its structure was researched and designed, including determination of setting chamber and pipe number, selection of material and the design of cyclones.
The Method on Modifying the Dynamic Properties of Self-Interactive Systems by External Factors
Authors: Wang Wei
Published: October 2011

As one of the general mathematical models of polymers, self-interactive systems have been studied extensively. In this paper, however, we investigate the method on modifying the dynamic properties of self-interactive systems by using external inputs. The main idea is that, based on the basic principle of control systems, we will introduce the external inputs to the system. And we will pay more attention to the possible influence of the purposeful external factors on the dynamic properties. Some interesting results can be obtained mainly based on simulation. So we can find many new properties or dynamic characteristics about the system. The research may also provide people with the possibility of improving the properties of Brownian dynamics of polymer chains.
Analysis on Tax Preferential Policies of Promoting University Students' Venture and Employment
Authors: Jiang Rong
Published: October 2011

As an important lever that the states adjust the economy, tax revenue plays a significant regulatory role in university students' venture and employment. The influence of preferential tax to university students' employment is mainly a guiding and driving role. Enough attractive preferential tax can drive university students’ venture, also can make the enterprise provide more jobs for college students in the guidance of the preferential tax. For domestic employment situation of serious college students’ employment difficulty, this paper discussed how to use tax reform means to improve the present situation of university students' venture and employment, and proposed the feasible tax reform measures.
Robust and Fast Spatial Verification
Authors: Wang Wen Ying , Guo Ru Jiang , Yu Hui , Tian Si Rui
Published: October 2011

Spatial verification for object retrieval is often time-consuming and susceptible to viewpoint changes. In this paper, we propose a novel spatial verification method that is robust to viewpoint changes. Firstly, the affine covariant neighborhoods (ACNs) of corresponding local regions are matched to eliminate possible false matches. Secondly, the RANSAC is performed to estimate the affine transformation from each single pair of corresponding local regions without the gravity vector assumption used in previous spatial verification methods. Experimental results demonstrate that this method is more robust and fast than previous spatial verification methods.
Numerical Simulation of Gas Flow Field in Gas-Liquid Hydrocyclone Separator
Authors: Jin Xiang Hong , Han Feng Shuang , Zhang Jin Liang , Huang Hui , Liu Xin Wen
Published: October 2011

The gas flow field in hydrocyclone separator was numerically simulated by applying RSM turbulence model, and the gas flow velocity distribution and stress distribution were calculated. According to the characteristics of gas flow distribution within the separator, it is found that: (1) the rotating strength of gas flow is related to the outlet angle of guide blade, the greater the outlet angle, the smaller the tangential velocity; (2) the obvious short circuit flow distribution under the exhaust pipe mouth area is easy to carry droplets and roll them out, causing a decrease in separation efficiency; (3) the high strength of turbulence pulse at mouth area of vent and drainage is easy to break the droplets and decrease their diameter, which affects the separation efficiency. The above research results lay the foundation for the structure optimization and the improvement of separation properties of axial guide vane cyclone gas-liquid separator.
The Testing Equipment Research of Auto Electric Window Lifter Performance
Authors: Li Qing Hua , Li Yue Guang , He Chun Shan
Published: October 2011

Based on the test requirement of auto electric window lifter, using the control method of the machine-electron-liquid, the test equipment was researched and designed, using the method of the swing load to realize the load, the method effectively reduce the impact to the auto electric window lifter, and has the characteristics of automatic loading and automatic unloading. The technology was used in actual test, and the test precision satisfies the design requirements.
Secondary Development of Automatic Drawing Software of Spindle of Numerical Control Lathe
Authors: Zhang Shu Lan , Zhang Nan Qiao
Published: October 2011

Looking up data mainly depends on the designer. Automation of looking up related data of charts, curve resource is a key to automatic design of common components, and is neccessory to be solved for strength and structural design automation of common components. A continuous curve on the logarithmic coordinates taken automatically search algorithm and discrete forms of data management and automated check to take the basic data structure to solve all the data graphs and charts automatically check the computer taken. With computer technology, in mechanical product design, various standards curves and tables can be processed.
Research of Recommended Service of Mobile Terminal Based on User Behavior Analysis
Authors: Liu Wei , Mu Dong Mei , Huang Dao Li , Hao Ji
Published: October 2011

Due to its portability, mobile terminals (mobile phones and similar devices) have become an transfer of information, between people as well as an important tool for network access. Based on user behavior analysis, using the information of data warehouse will be a reasonable quantification of qualitative indicators, draw the user a variety of potential semantic behavior, and user clustering and dimension reduction, the establishment of a recommendation based on user behavior analysis model . This paper based on user behavior analysis, first extract the user factors into the model are data on these factors reduce the dimensions of the conclusion that the targeted user recommendation system, and such user back into the model test to verify the target User's accuracy.
Design of Defense Algorithm Concerning Arp Attack on Campus Network
Authors: Zhang Hong Xing , Zhu Jin Shan , He Ke Jia , Wu Zhao Xiao
Published: October 2011

Since some security flaws exist in the arp protocol, some network attacks may arise such as arp overflow, arp spoofing and so on. By analyzing the modes of arp attack on campus network, the paper puts forward a defense algorithm against the arp attack. In the algorithm, the arp packets sent and receive by the host computer are to be detected ,and those differing ones are abandoned; In accordance with the policy of “receiving arp response after sending an arp request ”checks the arp response packets, those no-request ones are refused. The above defense algorithm can effectively prevent arp attacks, which can be applied in the campus network with high-safety requirements.
Principles of Collaborative Decision Making Application at Airport (Ukraine)
Authors: Wang Bo , Yang Shao Lan
Published: October 2011

This article deals with the general principles of airport collaborative decision making concept. The Euro control methodology of practical application of collaborative decision making at European airports and the long-term plan of implementation of concept in Ukraine are considered.
Developing Students’ Comprehensive Abilities through Mathematical Modeling Teaching
Authors: Ma Jun Er , Li Dong Ming , Zhu Dong Bi
Published: October 2011

The paper aims at improving students’ comprehensive qualities through mathematical model teaching and practice. The students can acquire better innovative and data-processing capacity. This paper clearly states that in mathematical model teaching, theory should be combined with practice to stimulate students’ thirst for knowledge, and proper cases should be chosen according to different majors, thus improving student’s application ability of mathematics and computers.
Ningbo Urban Logistics System Planning
Authors: Jia Chun Mei , Yu Ling Hong
Published: October 2011

With China’s rapid economic development, people's demand is also further expand the logistics. The logistics from traditional logistics to the current development of modern logistics, is a manifestation of the further expansion of the logistics requirements, therefore, since the reform and opening up, some of China's coastal regions and cities have recognized the urgency of the Development of Modern logistics, Modern logistics, as have The Main Pillars of economic Development, Industry, and to a Strategic height. It is in this case, I made Ningbo Urban logistics System Planning Study.
A New Formant Detection Algorithm Based on Cepstrum
Authors: He Jin Bao , Fan Hong Chao , Yi Xin Hua , Hu Jia Fen
Published: October 2011

Formant frequency is one of important parameters for speech signal. This paper presents a new formant detection algorithm based on cepstrum. Firstly, the traditional speech formant method is discussed. To overcome the weakness of traditional method, an extraction method based on formant enhancement is described. Then, the first-order derivative of phase-frequency characteristics has better frequency resolution than logarithmic amplitude-frequency characteristics, so the first-order derivative of phase-frequency characteristics based on formant enhancement is proposed. Finally, the experimental results show that formants parameters can be extract more precisely.
A SPH Based Particle System Editor for Computer Games
Authors: Zhan Yong Song , Chen Xian Jun
Published: October 2011

Particle system is an essential building block for visualize various types of special effects in applications of computer graphics. In this paper, we propose a novel approach based on particle system editor supported by GPU (Graphic Process Units) to provide a WYSIWYG (What You See Is What You Get) editing environment for simplifying special effects development process, where a SPH (Smoothed Particle Hydrodynamics) solver is used for particles movement simulation. Experimental results show the robustness and efficiency of the proposed system for computer games in real time.
Failure Mode Estimation with Inter-Fiber Failure Analysis of Composite Wind Turbine Blade
Authors: Kim Soo Hyun , Bang Hyung Joon
Published: October 2011

This paper provides an overview of the failure mode estimation result with 3D finite element (FE) analysis model of wind turbine blade. In order to predict the realistic behavior in the whole blade region, fiber failure (FF) and inter-fiber failure (IFF) analysis were applied to account delamination or matrix failure on composite materials. The Puck’s fracture criteria were used for the IFF evaluation. For the comparison of FE analysis result with the measured data of static test, a 3.5m down-scaled wind turbine blade was designed and fabricated using glass fiber epoxy composite materials. A nonlinear static structural analysis was performed and then the failure mode and the location were estimated with the FF and IFF analysis.
Surface Effects Considerations for the Design of Casimir Actuated Nanoswitches
Authors: Ma Jian Ming Bryan , Asokanthan Samuel F. , Jiang Li Ying
Published: October 2011

New techniques that can control Casimir forces in nanosacle structures may soon ensure the physical realization of switchable Casimir-force devices. In order to provide useful insights into the behaviour of this class of switches, the idea of Casimir-force actuation window has been proposed here to assist in the design of such switches. The influence of surface effects including residual surface stress and surface elasticity on the pull-in parameters of Casimir actuated switches has been demonstrated. These effects, together with other currently known difficulties due to uncertainties such as surface roughness and trapped electric charge may hinder the realization of this class of devices. An Euler-Bernoulli beam model has been employed to demonstrate surface effects in a nanocantilever switch, and numerical solutions employing a finite difference approach have been obtained for the static bending of this switch. The results demonstrate that surface effects play a significant role in the selection of basic design parameters of Casimir actuated switches, such as static deflection and detachment length. Threshold value of residual surface stress is also studied for these switches. The predictions reveal that exclusion of surface effects in Casimir-force actuation window may result in non-functional switch designs.
Research of Aerodynamic Performance of HP-Turbine with Coolant Injections for Variable Cycle Engine
Authors: Liu Zhi Gang , Fang Xiang Jun , Liu Si Yong , Wang Ping , Yin Zhao
Published: October 2011

A highly loaded high-pressure turbine with a supersonic nozzle guide vane and a transonic rotor for a Variable Cycle Engine (VCE) has been investigated. Film cooling strategies were designed for the whole stage, during which the positions, injection orientations and arrangements of cooling holes were confirmed. Three-dimensional steady numerical simulations have been performed in the two operation modes of low and high bypass ratio with different thermodynamic cycle parameters according to the VCE and the coolant injections have been simulated by means of additional source term method. The influences of coolant injections in the fully cooled turbine stage on aerodynamic performance and flow characteristics have been analyzed. The results indicate that, the supersonic nozzle guide vane, over-expansion degree of main flows, fluctuations of static pressure and intensity of corner vortex are lessened or alleviated. In the transonic rotor, expansion and doing work capabilities in the mixed fluid are strengthened. Proper coolants injections are beneficial to the flow characteristics in the blade passage.
Investigation into Electrorheological Fluid-Assisted Polishing Optical Glass
Authors: Zhao Yun Wei , Geng De Xu , Iu Xiao Min , Zhang Jin Tao
Published: October 2011

Electrorheological (ER) fluid-assisted polishing process is the ultra precision finishing technologies for micro-aspherical lenses and dies. The principle of ER fluid-assisted polishing (ERP) is to use ER effect as a result of the application of electric field. The ER particles and abrasive particles suspended in silicone oil are polarized in which ER particles strongly attract each other and aggregate into chain like structure along the electric field lines, and the abrasive particles may adhere to the ER chain. The force acting on ER particles and abrasive particles in an electric field is calculated. Furthermore, experiments of polishing optical glass with Al2O3 are carried out to find the influential regularities of polishing time, rotational speed of micro-tool, voltage, the density of abrasives in ER fluid on the surface roughness.
Study of the Heat and Mass Transfer in a Dehumidification of Liquid Desiccant
Authors: Salarian Hesamoddin
Published: October 2011

Desiccant systems have been proposed as energy saving alternatives to vapor compression air conditioning for handling the latent load. Desiccants are classified as either liquid or solid. The main components for a liquid desiccant system are the dehumidification and regeneration towers. This paper presents the results from a study of the performance of a packed tower absorber for lithium chloride desiccant dehumidification system. A finite difference model was developed to determine the packing height of the dehumidification towers. The finite difference model was written in MATLAB language which is a suitable model to measure the optimum height of a tower. The paper also examines the effects of different design parameters on the height of a packed tower using a mathematical model. The effects of air and liquid flow rates, air humidity, desiccant temperature and concentration were reported on the packing height and humidity effectiveness of the column. In conclusion the results of the present study are compared with previous experimental studies.
The Investigation of Electret Film Durability in Polyethylene Terephthalate (PET) from a Certain Angle of their Application as Pressure Sensors
Authors: Klimiec Ewa , Zaraska Wiesław , Kuczyński Szymon , Machnik Monika
Published: October 2011

Article presents research methods and their results for 100μm polyethylene terephthalate PET film, from a certain angle of its application as pressure sensors. Film was polarized at 150V/μm electric field intensity in dwo different temperatures: 60°C and 90°C. Direction of polarization was measured by thermally stimulated depolarization current TSDC. Results shows presence of homo-and heterocharge. Relaxation was calculated by two methods: from relationship ln J (T) = const – W/kT and from relationship (T) = P (T) / J (T). Activation energy for heterocharge calculated by first relationship is 6.14 eV to 6.77 eV and its relaxation time in 24°C is ~1020 years. For second one relationship, relaxation time in 24°C is ~1035 years. Piezoelectric voltage in 33 direction is 74V for termination resistance 1014Ω and 30V for termination resistance 109Ωfor applied stress 10N/cm2 from 10 cm2 surface. Obtained results for studied PET film, encourage to use it in practice as pressure sensors.
Effect of Niobium/Molybdenum Microalloying on SS316LN Steel
Authors: Dhal Jyoti Prakash , Mishra Subash Chandra
Published: October 2011

In recent years SS316LN microalloyed stainless steel is preferred for use as jacket material for Nb3Sn superconductor strands/wires. In the present investigation, microalloyed SS316LN is prepared in a vacuum induction melting furnace; Niobium and Molybdenum in their ferroalloy stage are considered as alloying element. This microalloyed steels are cast in water cooled copper mould. The tensile strength and elongation are measured and the fracture surface is studied under scanning electron microscope. It is observed that, there is a reduction of tensile strength and decrease in hardness of the steels prepared with addition of either/both the alloying elements; however there is an increase in ductility, which is helpful for cold rolling operation. From the micrographs it is observed that nitride precipitates are formed along the grain boundary, but formation of chromium carbide precipitates is reduced.
The Effect of Quenching in Polymer and Addition of 0.1% Zr on Properties of Al-5.6% Zn-2.5%Mg-1.6%Cu Alloy
Authors: Salman Jassim Mohammed , Al-Sultani Khadim Finteel , Abedulsada Shymaa Abbas
Published: October 2011

The Al-Zn-Mg-Cu aluminum alloys are primarily used in the aerospace industry as structural components. This study aim to improve properties of Al-5.6% Zn-2.5%Mg-1.6%Cu such as impact toughness, thermal stability and corrosion resistance by using quenching in 30% polyethylene glycol and addition 0.1%Zr to this alloy. Results showed that the addition 0.1% Zr to base alloy improve impact toughness by (40%) when quenching in water, and by (60 %) when quenching in 30%PAG corresponding to the base alloy when aging at 150 °C. Also results showed that the thermal stability improved when we addition 0.1% Zr by (20%). An improvement of corrosion resistance when addition 0.1% Zr (B alloy) by (326 %), at aging time 150°C in comparison to the base alloy.
Effect of Abrasive Medium Ingredients on Finishing of Al Alloy and Al Alloy/SiC Metal Matrix Composites Using Rotational Abrasive Flow Finishing
Authors: Sankar M. Ravi , Jain V.K. , Ramkumar Janakarajan
Published: October 2011

Al alloy/SiC composites possess better mechanical and physical properties thus finding applications in automotive, sports, and aerospace. In some cases, these components require nanolevel finished surface. But, traditional abrasive finishing processes are labor intensive, time consuming and confined to only simple geometries. Abrasive flow finishing (AFF) is one of the advanced finishing processes that can be used to finish complex surfaces by flowing polymer based abrasive medium but its finishing rate is low. In the present work, Rotational-AFF (R-AFF) process is developed where in workpiece rotates about its axis. This rotation provides the dynamic motion (additional force and velocity components) to the workpiece. By cumulative effect of workpiece rotation and medium reciprocation, the active abrasive particles try to abrade the workpiece in a helical path. Thus, finishing length and finishing rate both increase. In AFF process, because of more finishing time medium undergoes chemical change or degradation (loses its viscosity) because of continuous shearing and rise in temperature. Therefore the effect of medium shear viscosity variation with the temperature is studied to understand how the viscosity reduces with the temperature. Later complete experiments are conducted on R-AFF process by varying plasticizer to polymer volume ratio and polymer to abrasive ratio. The finishing from micron surface topography to nanosurface topography is studied using atomic force microscopy.
Performance Evaluation of Thermal Interface Material for Space Applications
Authors: Gandhi Jigar , Pathak A. V.
Published: October 2011

Thermal interface material is one of the many tools often used as part of the thermal control scheme for space-based applications. An experimental investigation was conducted to better understand the effect of graphite based thermal interface material under vacuum condition. The heat transfer ability of different interface materials was evaluated. Theoretical and experimental studies have yielded valuable data which provide an insight into the complexity of the problem and a better understanding for future development.
An Energy Model for Fatigue Life Prediction of Composite Materials Using Continuum Damage Mechanics
Authors: Movaghghar A. , Lvov G. I.
Published: October 2011

In this paper an energy-based model for predicting fatigue life and evaluation of progressive damage using plane-stress assumption is proposed. This model allows us to predict fatigue durability taking into account principal directions of the stress tensor relative to planes of elastic symmetry of material. First, the unknown parameters of this model will be calculated for three different composites with various lays-up. Method for determining these parameters is based on the minimum necessary set of experimental data. Afterwards the model was used to predict fatigue life and estimate accumulated fatigue damage in a unidirectional composite under different angles of loading. The analysis of conclusions of the theory for various loading conditions was carried out and performed comparison between the experimental data and predicted results. The predicted fatigue lives obtained by the proposed energy model were in good agreement with the experimental data.
Study on the Sol-Gel Process of TEOS by React-IR
Authors: Zhou Hua Hua , Xue Wei , Li Fang , Qin Yan Fei
Published: October 2011

Porous silica was prepared through TEOS sol-gel process catalyzed by acid-base joint catalyst, and the process was monitored by React IRTM. Based on the measurements, mechanism of TEOS hydrolyzation and succedent condensation polymerization was inferred. Under acidic conditions, H+ attacks –OR group of TEOS firstly, then the electronegative Cl- can attack Si4+ and make TEOS be hydrolyzed. When basic catalyst was added, the reaction will be accelerated. The promotion effect of base is attributed to the direct nucleophilic reaction mechanism and the smaller size of OH-, which can attack Si more easily. Thirdly, silanol, generated from TEOS hydrolyzation, attract Si-OR or other Si-OH around; thereby resulting rapid dehydration or de-alcohol reaction. So the condensation polymerization rate is elevated, and Si-O-Si bond comes into being. Lastly, cross-linking reaction among Si-O-Si bonds forms the particle like conglomeration. The porous silica was characterized by SEM and N2 adsorption-desorption technique. It was shown that the silica had large specific surface area, 818.5 m2/g, and relatively narrow distribution of pore size in meso-scale. Futhermore, the mesopores were nonuniform in shape and arrangement.
Ball Milling of WC-Co Powder as Injection Molding Feedstock
Authors: Amin Sri Yulis M. , Muhamad Norhamidi , Jamaludin Khairur Rijal , Fayyaza Abdolali , Yunn Heng Shye
Published: October 2011

In this paper, an attempt has been made to mill constituent of WC and Co powder towards achieving volumetric percentage of WC (91%) and Co (9%). The ball milling technique was conducted under dry and wet condition using various milling parameters, rotation speed, time and ethanol as milling medium. Electron dispersive spectrometer (EDS) detected the elemental distribution, whilst SEM and particle size analysis was done to study the effect of changes in particle morphology and reduction of particle size. As a conclusion, powder milled by parameter of wet milling by ethanol, speed of rotation at 250 rpm and 90 minutes of milling time exhibits best results in term of volumetric percentage of 91%WC and 9%Co and particle size reduction.
A Study on the Stability of Curvic Coupling for Distance to Disk in a Mill Turret
Authors: Choi Jih Wan , Kim Chae Sil
Published: October 2011

Curvic coupling of mill turret should maintain disk weight and the cutting resistance, which occurs when the machining operation must have a power transmission function. In order to improve machining operation range, distance to the disk must increase as much as possible. But moment is increased by the lack of bearing capacity of the curvic coupling. Increase of moment is the cause of vibration/noise and degradation of machining performance, it not only a stability problem. In this study, a finite element analysis model of the mill turret is designed and considered in the method of equations for finding distance to the disk by structural analysis of Ansys workbench. Through the considered method, critical distance to the disk, and the stability of the curvic coupling are confirmed by increasing each value 10mm from 228.5mm
The Effect of Pressure Induced Hoop Stress on Bi-Axially Loaded through Wall Cracked Cylindrical Structures – A Strain Based Method
Authors: Sivakumar M.V.N. , Rao B. N. , Satishkumar S. R.
Published: October 2011

This paper presents a simplified strain-based fracture mechanics approach to study the effect of pressure induced hoop stress on bi-axially loaded through walled cracked (TWC) pipes subjected to an external bending load in combination with internal pressure. Elastic-plastic finite element analyses are conducted to establish the relation between global strain and Crack tip opening displacement (CTOD). In the finite element model X65 pipeline steel is considered using power-law idealization of stress-strain, and the inelastic deformations, including ductile tearing effects, are accounted for by use of the Gurson–Tvergaard–Needleman model. Several parameters are taken into account, such as crack length, internal pressure and material hardening. Strain based crack driving force equation is used and maximum load criterion is adopted to determine the critical strain from ductile tearing in the cracked pipeline. The results suggest that presence of pressure-induced hoop stresses increases the fracture response in high-hardening materials and their effects are significant due to large plastic-zone size.
Near Time Optimal Path Control of Kinematically Redundant Manipulators with Bounded Joint Velocities and Torques
Authors: Ghasemi Mohammad Hassan , Kashiri Navvab , Dardel Morteza , Pashaei Mohammad Hadi
Published: October 2011

here, a time optimal control scheme for trajectory planning of kinematically manipulators subjects to actuator torque limits is proposed by using the phase plane analysis and linear programming technique. In addition, the limit on joint velocities is considered. In order to affect the constraint of joint velocities, this constraint is converted to constraint on joint acceleration and it is affected linear programming problem as an additional constraint. Also, an explicit algorithm for finding the switching points is presented. To this end, some simulations are given to demonstrate the efficiency of proposed trajectory planning algorithm.
Multi Response Optimization of the Hole Punching Process Parameters in the Leaf Spring Assembly Using the Grey Taguchi Method and Simulated Annealing Algorithm
Authors: Gopalaramasubramaniyan Gopalsamy , Zhu Ke
Published: October 2011

This paper presents an attempt to develop an approach to predict the optimal process parameters for the Hole punching process on sheet metal. The Taguchi method is used to define the experimental procedure by its orthogonal array. The multiple responses of the Hole punching process, hole diameter and hole offset are optimised by the Grey Relational Analysis procedure. The statistical analysis of variance reveals the significant parameters which affect the process by analyzing the input parameters with the grey relational grade. The Non linear model obtained by this analysis is further processed by a Meta heuristic algorithm to obtain the optimality.
A Framework for a Feature Based Machining Using Macro
Authors: Al’Hapis M. , Razak A. , Zakaria Ahmad
Published: October 2011

This paper describes a research work to explore the utilization of macros in an effort to improve an overall machining efficiency. Latest models of CNC machine are equipped with many functions and resulting difficulty in creating NC program. Feature based machining is optimizing the capabilities of CNC machine. A novel framework of a feature based machining system using macros is discussed in this paper by applying some normally used features and work material in manufacturing industry. Experiments has been conducted in proving its functionality. This system found enable to reduce pre-machining setup time and easy to used. Lastly, a graphical user interface is proposed.
Anisotropic Nanocomposite Hydrogels with High Mechanical Strength Using Hydrophilic Reactive Microgels and Self-Assemble
Authors: Qin Xu Ping , Zhao Fang , Feng Sheng Yu
Published: October 2011

Anisotropic hydrogels based on acrylamide were prepared by frontal photopolymerization. First hydrophilic microgels (HM) were spreparaed by inverse emulsion photopolymerization, and secondly hydrophilic reactive microgels (HRM) with C=C double bonds were synthesis by chemical modification of the HM used N-methylolacrylamide, Last, HRM hydrogels were synthesis by frontal photopolymerization using HRM as crosslinkers. Only one direction of the HRM hydrogels show excellent fracture strength and tensile elongation but the other two directions show little fracture strength and tensile elongation. The reason of the high mechanical performance in the given direction is that the hydrogels are crosslinked by HRM as a new crosslinking agent instead of the conventional crosslinking agents and these nanoparticles can self-assemble into anisotropic structures and the structure can be stabilized by free radical polymerization. The anisotropic hydrogels could use potential materials such as artificial muscles tissue.