bluuebunny/crossref_metadata_2025 huggingface dataset:
The Dynamic Optimization and a New Structure of the Nursing Bed Robot
Authors: Xin S.J. , Zhang H.H.
Published: January 2010

In line with the principle of ergonomics and mechanism and based on bar linkage ,this thesis puts forward a nursing bed robot with the introduction of its structure and working principle. According to the many-body system dynamics theory and by the application of the simulation software ADAMS of mechanical system dynamics ,we first set up the pattern of the virtual model machine which posses a nursing bed with the combined linkage of sitting up straight with its knees bent. And second we successfully optimized the dimensions of the structural parts of the nursing bed robot by realizing the design goal of minimizing the maxi force intensity borne by the linear motor .Finally following the result of optimization and the optimal scheme which satisfies the design requirements, we made the model machine of the nursing bed robot.
Study on Desktop Virtual Assembly System for Interactive Assembly Process Planning
Authors: Zhang Dan , Jiao Guang Ming , Zuo Dun Wen , Xie Jian , Li J.P. , Zhou Hua Lin
Published: January 2010

Aiming at the shortcomings of traditional assembly process design and immersive virtual assembly system, the architecture of Desktop Virtual Assembly System (DVAS) for interactive assembly process planning is presented. The key technologies such as data conversion and reconstruction of assembly models, assembly intention recognition and assembly control navigation are studied. The lightweight storage of assembly models’ data and the intelligent constraints recognition are realized. The problem of assembly operations resulted from the lack of immersion is solved by movement navigation. The algorithms were proposed and applied to the DVAS prototype, and an application case is studied to demonstrate the effectiveness of the system.
Study of Intelligent Controller Based on FWN Oriented to Indirect Nonmetal Rapid Tooling
Authors: Zhang Hai Guang , Hu Qing Xi , Liu Yuan Yuan , Wang J.W. , Chi Z.F. , Huang H.J.
Published: January 2010

As one key technology of Rapid Tooling (RT), Indirect Nonmetal Rapid Tooling (INRT) has been used widely, so this paper analyzed the modeling process of INRT and concluded that the velocity of stirring and casting are key factors which affect products quality and production efficiency. In nature, just need to control the speeds of driving motors. In order to resolve problems of existing modeling equipments, such as strong dependency on operators experience and low control precision, this paper studied an intelligent controller model based on Fuzzy Wavelet Network (FWN) which integrated wavelet analysis and fuzzy neural network technologies. The structure and implementation algorithm of FWN are introduced in detail. After considering the advantages of Permanent Magnet Synchronous Motor (PMSM), the INRT equipments use it as driving motors. Because it is nonlinear, uncertain, coupled, sensitive and multivariable system, this paper made improvement on traditional IP controller, FWN acted as error compensator which can compensate for disturbance influence and trace expected speed in real time. The IP intelligent controller based on FWN can strengthen interference ability. The robustness of this control system has been verified by simulation experiment. This controller realized closed loop control of stirring and casting motor and improved the products quality and control precision of INRT.
Development of PCD Combined Tool for Machining Cylinder Block
Authors: Wang Yong Guo , Liu G. , Zhang J.S. , Yu Jian Bo , Li M.
Published: January 2010

4 blades PCD combined tool used for hole reaming and chamfer milling Al-alloy cylinder block has been developed. Results showed that the tool life of this PCD tool is 21.5 times than the former carbide tools made by Japanese company, the surface roughness of the hole is Ra0.2, better than the required Ra3.2, the 90 chamfer surface roughness is Ra1.6, better than the required Ra25.
Investigation into the Grindability and Surface Integrity of the Nickel Base Superalloy Using Liquid Nitrogen Jet Grinding
Authors: Li Chang He , Hou Ya Li , Ding Yu Cheng
Published: January 2010

Grinding processes are mainly technique employed widely as a finishing process in a variety of materials, such as metals, hardness and brittleness and ductile materials machining to achieve good dimensional and form accuracy of the product with acceptable surface integrity. However, grinding is associated with high specific energy requirements which may be an order higher than that required in other conventional machining processes such as turning, planning, milling etc. Therefore, in grinding process, high grinding zone temperature may lead to thermal damage to the work surface, induces micro-cracks and tensile residual stresses at the ground surfaces, which deteriorate surface quality and integrality of the ground surface. Therefore, grinding fluids are applied in different forms to control such high temperature, but they are ineffective, especially under high speed grinding conditions where the energy of the fluid is not sufficient to penetrate the boundary layer of air surrounding the wheel. Moreover, the conventional flood supply system demands more resources for operation, maintenance, and disposal, and results in higher environmental and health problems. Therefore, there are critical needs to reduce the use of cutting fluid in grinding process, and cryogenic cooling grinding is a promising solution. The work presented in this paper aims at evaluating the grind ability and surface integrity of the nickel base super alloy resulting from the application of cryogenic cooling.
Research on the Mechanism of Sludge Dewatering Treatment by High-Voltage
Authors: Wu Z.Y. , Chen H.J. , Rui Yan Nian
Published: January 2010

This supersonic splitting treatment of high- water ratio of sludge is studied by the mechanism of focusing of high voltage pulse discharge. Meanwhile, the theoriotical methods and relative parameters are deeply discussed by experiment and satisfactory result is received. The research of this item presents a new practical and effective method for the treatment of high-water ratio sludge.
Methods to Control Financing Risks in Colleges and Universities
Authors: Zhang S.H.
Published: January 2010

With the great development of higher education and more and more autonomy in college running, the financing risks in college finance management have become increasingly foregrounding in China. Under such a new situation and condition, it is necessary to strengthen research and practice of the risk control of college financial affairs management so as to accelerate the sustained development of various tasks in Chinese colleges and universities.
HSM Strategies of CAD/CAM Systems — Part I Tool Path Generation
Authors: Ding Song Lin , Mo John , Yang D.
Published: January 2010

Owning to the ultra high feed rate and spindle speed, tool path patterns which are less important in conventional metal cutting processes becomes critical in High Speed Machining (HSM). Without an appropriate tool path strategy HSM can not be fully implemented even though the CNC machine has HSM potentials. In practice attentions are usually drawn to advanced hardware components; tool path pattern catering to HSM is often overlooked. This paper introduces the principles of tool path generation for HSM. Essential properties of HSM and its technical requirements on the CAD/CAM system are summarized. The state-of-the-art technologies and practice-oriented tool path generation methodologies are presented.
A Study on Application of the Honeycomb Structure in the Large-Scaled Parts
Authors: Yin F.H. , Guo H.
Published: January 2010

The Application of honeycomb structure was studied for the large-scaled structures in the paper. Stress and strain distribution of different nephogram structure is gained by the finite element method (FEM), the simulation results are discussed. Based on above-mentioned analysis, the evaluation of distortion is accomplished. The research provides a useful reference for the design of large-scale structure; it has had a certain project practical value and theoretical research value academically.
Study on Influence of Machine Tool Thermal Deformation During ELID Super-Precision Grinding
Authors: Jin W.D. , Tang Guo Xing
Published: January 2010

For ELID (Electrolytic In-process dressing) super-precision grinding, as the result of machine tool thermal deformation, actual grinding depth is much less than nominal grinding depth. However, controlling accurately grinding depth is more significant for realizing normal grinding process, increasing material removal rate and analyzing rightly material removal mechanism. In this paper, based on study of thermal deformation law and compensating technique, three feeding strategies for ELID grinding was analyzed. On the premise of measuring of total thermal deformation of machine tool, indirect compensating numerical value may be preset to ensure effective contact between wheel and workpiece, and right evaluation method of material removal rate was explored.
Stress in Freestanding CVD Diamond Thick Film
Authors: Lu Wen Zhuang , Yuan Jia Jing , Zuo Dun Wen , Xu Feng , Sun Yu Li
Published: January 2010

The present paper describes research on stress in freestanding diamond thick film, diameter of 60mm, prepared on Mo substrate by DC arc plasma jet chemical vapor deposition (DCPCVD) method. The stress in the CVD diamond film was investigated by X-ray diffraction and Raman spectrum. The results show that the stress in the film is compressive. The stress changes little at the same homocentric round. The compressive stress along radial direction is that the stress in the centre of the film is lower than that in the edge at both the final surface and the original surface.
Five-Axis HSM Tool-Path Planning of Integral Impeller
Authors: Zhao Can , Guo Y.Y. , Bu Guang Bin
Published: January 2010

There are two key problems in the manufacture process of impeller with HSM(High Speed Machining). One is the collision between tool and blade, the other is gnawed-cutting arisen by non-uniform change of the cutter axis. The control algorithm of collision-free cutter-axis was described and applied in this paper. The cutter-axis vector was optimized by quaternary linear interpolation method to make normal vector of blade changing continuous, so. These methods were synthetically used in the manufacture experiment. And the qualified impeller was produced. It indicated that the tool vector control method was feasible.
Fixed Abrasive Lapping and Polishing of Hard Brittle Materials
Authors: Li Jun , Zhu Yong Wei , Zuo Dun Wen , Lin Kui , Li M.
Published: January 2010

Fixed abrasive lapping and polishing (FALP) is a new machining technology and was adopted to manufacture hard brittle materials and obtain the high productivity because of fixed abrasive. The preparation process of fixed abrasive pad (FAP) was described. FALP of K9 glass, mobile panel glass and Si were investigated with fixed 5-10 µm diamond abrasives. The effect on material removal rate (MRR) and surface quality of different materials was studied. The results show that in the same FALP process conditions, Si is the highest MRR and reaches 4428 nm/min, mobile panel glass is inferior to and K9 glass is the lowest. And surface quality of mobile panel glass that surface roughness Sa is 2.10 nm and little and less damages is the best, Si is followed and K9 glass is the worst. So FALP can obtain the higher MRR and reaches several micrometers per minute and the better quality that surface roughness Sa can reach nanometer level for different materials.
Parametric Sensitivity Analysis of Fuzzy Reliability Based on the Cut-Set of Fuzzy Mathematics
Authors: Cheng X.J.
Published: January 2010

The problem of the parametric sensitivity of fuzzy reliability analysis was discussed in this paper. Firstly, based on the concept of cut-set of fuzzy mathematics, a computational model is introduced. Then, the expression of cut-set of fuzzy mathematics is built in the case of normal random stress and normal fuzzy strength, and the effect of each parameter is analyzed. Finally, a simulation method is given to obtain the numerical solution of parametric sensitivity, and its validity is proved successfully by an example.
Thermal Modeling and Analysis for Grinding Operation
Authors: Qin Yan Ding , Tian Yan Ling , Zhang Da Wei
Published: January 2010

This paper focuses on the effects of heat source profiles during thermal analysis of grinding. Three different models of heat source, namely triangular model, parabolic model and elliptic model, have been suggested and their numeric formulas are provided. These models take into account of the variation of heat flux along the contact zone, so as to improve the accuracy of numeric results. Finite Element Analysis (FEA) is utilized to investigate the temperature distributions under different thermal models and the effects of two profile parameters (η and ξ). The result is a) peak temperature decreases as η increases and the location of peak value moves backwards simultaneously; b) peak temperature decreases as ξ increases and the location of peak value moves forwards simultaneously.
On the Dynamics of Bull-Nose Plane Six-Rod Mechanism Considering some Practical Factor
Authors: Li C.M.
Published: January 2010

Taking the mechanics characteristic of electromotor, the mass of slide and the sliding friction into account, the resolving calculating formulae for the kinematics and dynamic analysis of bull-nose plane six-rod mechanism is educed based on the dynamics principle. The disposing method of friction force operation direction is proposed. The computing simulation of this mechanism shows that the speed fluctuation would be aggrandized with the friction considered and the periodic change of friction force direction would be presented in the periodic change of acceleration. At last, the adding flexible component for the computing simulation near to actual movement is pointed out.
The Research on Wear Mechanism of Micro-Automobile Clutch Friction Material
Authors: Lv Jun Cheng , Mo Yi Min , Pan L.
Published: January 2010

According to the national test standards for constant speed friction tester :GB/5763-98, the sample test is designed which suits for the study of the micro-automobile clutch friction material’s properties, and the experiment data has been analyzed, and also using X-ray diffraction and Scanning electron microscopy(SEM) to analyze the friction coefficient of friction material, changes in wear quality and the formation of friction work surface layer, the final conclusion has been made that the micro-automobile clutch sliding wear consist of mild wear and severe wear; The friction surface of mild wear is relatively rough, while the friction surface of severe wear is relatively smooth or with obvious noise; mild wear mostly appears as oxidation wear and abrasive wear and normally with the adhesive wear together, while severe wear is mostly induced by severe plastic deformation(serious delaminating wear) , and mostly appears as adhesive wear and abrasive wear.
Application of UG/Open GRIP Technology in 3D Design of Splicing Chamber
Authors: Chang De Gong , Yang Z. , Xin Long Sheng
Published: January 2010

Using UG/Open Grip technique, the 3D parameter design of the splicing chamber was achieved by a computer program and the parameters could be modified through the interactive operation. This work strengthens the interactive design function of the CAD system and has an important significance for improving the design quality of the splicing chamber.
Influencing Factors Analysis of the Crack on Laser Cladding of Valve Sealing Surface
Authors: Fu Ge Yan , Shi Shi Hong
Published: January 2010

Thick laser coating on sealing surface of high parameter nuclear and chemical valve have been made, And the factors that will influence layer’s cracking behavior have been analyzed including laser cladding material, technology and base metal. It is approved by experiment that the greater the energy ratio is, the lower the possibility of cracking would be. But this case may cause diluting rate of the coat increasing, grains coarsening and hardness reducing. B and Si can create hard phase, reduce coating’s plasticity, and generate segregation easily in Ni-base alloy which may cause crystal crack. The rate of coating cracking will reduce when substrate has homogeneous structure, no relict stress, no defect, good plasticity, and, its rate of heat expansion is a bit higher than clad material, heat capacity is small, shape and structure is simple and heat symmetrical characteristic is good.
Green Laser Drilling Assisted with Jet Electrochemical Machining of Nickel-Based Superalloy
Authors: Zhang H. , Xu Jia Wen , Wang J.M.
Published: January 2010

Laser drilling is extensively used in the aerospace and aircraft industries. The most important application is the drilling of fine cooling holes in aero turbine engine components such as nozzle guide vanes and blades. However, laser-drilled holes are typically associated with a number of inherent defects such as recast layer and spatter. In order to solve these problems, a novel hybrid process of laser drilling assisted with jet electrochemical machining (JECM-LD) has been developed to improve the overall quality of laser-drilled holes. The process based on the application of a jet electrolyte, being aligned coaxially with the focused laser beam, on the workpiece surface. The effects of the jet electrolyte during the process mostly consist of electro chemical reaction, effective cooling with materials and transporting debris. A pulsed Nd:YAG laser with frequency doubling is used in the JECM-LD experiments. On the basis of a measurement of laser attenuation in electrolyte, an experimental apparatus system is built and JECM-LD experiments are performed on 0.5mm thickness nickel-based superalloy sheets with the system. The optical microscope is used to detect the experimental results. It is found that the recast layer and spatter have been effectively removed during the JECM-LD compared with laser drilling in ambient atmosphere conditions. The efficiency of JECM-LD with millisecond green laser is about 70% of laser drilling in air.
Synthesis and Characterization of a New Organometallic Palladium Coordinated Liquid Crystal
Authors: Liu Jian Qiang , Zhang Xing Cheng , Dai You Yong , Xiao Hong Di , Yan Shi Shen , Hou Wan Guo
Published: January 2010

A new organometallic palladium coordinated liquid crystal that is written by PdS4 has been synthesized by chelating reaction of the tetrachloropalladate (PdCl42-) and the star-like liquid crystal (S4) containing four butoxyazobenzene mesogens in its periphery. The structure and liquid crystallinity (LC) of PdS4 were characterized by infrared absorption spectroscopy (IR), ultraviolet absorption spectra (UV), nuclear magnetic resonance spectroscopy (NMR), elemental analysis (EA), polarizing optical microscope (POM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The phase behavior of PdS4 is Cr167N232I200N170Cr, its melting point and clearing temperature are higher than those of the free azo ligand S4, its mesophase range is broader than S4’s. It will be used as a new type photoelectric functional material in the future.
Synthesis and Properties of Thermotropic Liquid Crystalline Polyesters with Flexible Polymethylene Spacer
Authors: Lu Wei Zhong , Wei Chun , Gao Qui Shan
Published: January 2010

Polymethylene bis(p-hydroxybenzoates) were prepared from methyl p-hydroxybenzoate and different diols by melted transesterification reaction. Three liquid crystalline polyesters were synthesized from terephthaloyl dichloride and polymethylene bis(p-hydroxybenzoates). Its structure, morphology and properties were characterized by Ubbelohde viscometer, Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimetry (DSC), polarized optical microscopy (POM) with a hot stage, and wide-angle X-ray diffraction (WAXD). Results indicated that the intrinsic viscosities were between 0.088 and 0.210 dL/g. Optical microscopy showed that the TLCP has a highly threaded liquid crystalline texture and a high birefringent schlieren texture character of nematic phase and has wider mesophase temperature ranges for all polyesters. DSC analysis were found that the melting point (Tm), isotropic temperature (Ti) of TLCPs decreased and the temperature range of the liquid crystalline phase became wider with increased number of methylene spacers in the polyester. The WAXD results showed that TLCPs owned two strong diffraction peaks at 2θ near 19° and 23°.
Properties of Poly(4-hyderoxybenzoate) Oligomer and its Blends with Poly(trimethylene Terephthalate)
Authors: Run Ming Tao , Hu Xiao Min , Sun Mei Bo , Ma Wei Tao
Published: January 2010

The poly(4-hydroxybenzoate) (PHBA) oligomer was synthesized by using the monomer of 4-acetoxybenzoic acid (PABA), and its blends with poly(trimethylene terephthalate) (PTT) are prepared by melt-blending at 250oC in nitrogen. Their chemical structure characterization and crystal morphology were investigated by using the fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1HNMR), and polarizing optical microscopy, respectively. The results suggest that PHBA oligomer with 3 polymerization degree was synthesized and it is a thermotropic liquid crystal with the nematic characteristics. When the blends crystallize from melt, because the rigid oriented PHBA molecules becomes the nucleating agents for PTT molecules’ crystallization, much transcrystalline layers formed in the blends, although the crystalline PTT/PHBA blends show spherulites morphology character without observing nematic LC phase.
Synthesis and Mesomorphic Properties of Three-Ring Containing Bent-Core Liquid Crystal 1,3-Phenylene-bis(4-butoxybenzylideneamine)
Authors: Huang Yuan Ming
Published: January 2010

A three-ring containing bent-core compound 1,3-phenylene-bis(4-butoxybenzylidene amine) was synthesized and characterized with differential scanning calorimetry and polarized optical microscopy. It exhibited mesophases in the temperature range of 48-54oC for the first cyclic heating and cooling. Our results demonstrated that three-ring containing bent-core molecules can form mesophases.
Electric-Field Effects in Dilute Suspensions of Carbon Nanotubes Dispersed in Nematic Liquid Crystals
Authors: Rahman Muklesur , Lee Wei
Published: January 2010

Colloids composed of liquid-crystal hydrosols exhibit a rich set of interesting phenomena. The coupling between liquid-crystalline media and colloidal particles plays an essential role leading to an abundant source of new physics. In the last few years, peculiar behaviors of carbon-nanotube-doped calamitic liquid crystals have attracted considerable attention. This paper provides a brief introduction to this alluring subject for its on-going research development in this laboratory. First presented are our current understandings of the nematic colloidal system comprising carbon nanotubes and of their possible orientation and dynamics under the application of an external field. Various electro-optical and electrical properties of a liquid-crystal display rectified by the nanoscale carbonaceous guest are then addressed to a larger extent. Dielectric relaxation obtained from a nematic impregnated with carbon nanotubes is also discussed. With historical significance for the dawn of the liquid-crystal–carbon-nanotube research, several important findings of enhanced nonlinear optical properties in typical nematic mesomaterials consisting of suspended nanotubes are delineated. With the new colloidal systems of elongated nanoscale solids dispersed in anisotropic fluids in the mesophase, many new intriguing phenomena are awaiting theoretical and experimental explorations. Collaborations are called to draw attention of interested theoretical physicists, in particular.
Effect of Temperature on the Columnar Tilt of Discotic Liquid Crystals
Authors: Zheng Wen Jun , Chiang Chen Yan , Ong Chi Wi
Published: January 2010

The effect of temperature on the tilt of discotic columns in a columnar phase has been studied. The homogenous alignment of discotic columns is achieved by applying a mechanical shearing. In the columnar phase, the tilt of the discotic columns at substrate surface is found to change with temperature. A decrease in the temperature of the substrates causes an increase in the pretilt of the discotic columns. The phenomenon is explained based on the consideration of surface free energy at the interface of the substrate.
Photostability of an Antiferroelectric Banana-Shaped Liquid Crystal
Authors: Chen Lan Li , Zhai Bao Gai , Huang Yuan Ming
Published: January 2010

We have investigated the photostability of an antiferroelectric banana-shaped liquid crystal 4-chloro-1,3-phenylene bis [4-(4-n-tetradecyl) phenylimino methyl] benzoate by measuring its polarization as a function of photo-irradiation duration. Upon intense photo-irradiation for three hours, the banana-shaped liquid crystal exhibits a significant photostability although it bears the linkages of –COO– and –CH=N–.
Dispersion Properties of Nonlinear Bulk Polaritons in Uniaxial Antiferromagnetic Film
Authors: Bai Jing , Fu Shu Fang , Wang Xuan Zhang
Published: January 2010

Nonlinear bulk polaritons in uniaxial antiferromagnetic film are investigated under a magnetic field that is along the anisotropy axial. The numerical calculations show that the nonlinear shift in frequency is very obvious. The antiferromagnetic film presents the strong anisotropy under the magnetic field.
Photochemistry in an Azo-Containing Banana-Shaped Liquid Crystal
Authors: Zhai Bao Gai , Chen Lan Li , Huang Yuan Ming
Published: January 2010

By triangular wave method, the polarization currents of an azo-containing banana-shaped antiferroelectric liquid crystal were investigated as a function of the time of 365-nm ultraviolet irradiation. Under the 365-nm irradiation, the polarization currents were observed to evolve with the time of ultraviolet irradiation until they diminished. The roles of photoisomerization, photolysis and thermolysis were discussed for the azo-containing banana-shaped liquid crystal.
Optical Absorption and Light Emission of a Banana-Shaped Liquid Crystal
Authors: Huang Yuan Ming , Zhai Bao Gai
Published: January 2010

With the ultraviolet-visible spectrometer and photospectrometer, we have investigated the optical absorption and light emission from the dilute tetrahydrofuran solutions of a classical banana-shaped liquid crystal 1,3-phenylene-bis[4-(4'-nonyloxy)phenyliminomethyl]benzoate. In the dilute tetrahydrofuran solutions, three optical absorption bands were recorded for the banana-shaped compound at about 255, 290 and 355 nm, respectively. Upon the 325 nm excitation, white light emissions were recorded for the solid phase of the banana-shaped liquid crystal whereas blue-greenish emissions were observed for the banana-shaped molecules in dilute solution.
Effect of Molecular Shape on Polymeric Liquid Crystal
Authors: Fu Shu Fang , Bai Jing , Zhou Sheng , Qu Xiu Rong , Li Hua , Wang Xuan Zhang
Published: January 2010

The effect of molecular shape on molecular configuration of liquid crystalline polymers under shear flows is numerically analyzed using the extended Doi theory. We can find that the molecular shape strongly affects on the transition among flow-orientation modes. The change in sign of the first normal stress difference is to speed up by the increasing .
Concentration-Dependent Light Scattering in Lyotropic Liquid Crystal Formed by Sodium Dodecyl Sulfonate
Authors: Liu Wei Wei , Huang Yuan Ming
Published: January 2010

Lyotropic liquid crystal synthesized by sodium dodecyl sulfonate in the mixed solvent of distilled water through make the different concentration. Using Polarized optical microscopy and ultraviolet-visible spectrometer and theoretical simulation, we have studied the relation between the samples concentration and light scattering. Our results have demonstrated that natural light scattering increased with the samples concentration increased. The results we have gotten now are almost equal to our theoretical simulation.
Study on Crystal Morphology and Melting Properties of the Isothermally Crystallized Poly(trimethylene Terephthalate)
Authors: Run Ming Tao , Hao Yan Ping , Song Hong Zan
Published: January 2010

The spherulites’ morphology and melting properties of the poly(trimethylene terephthalate) formed in limited space at specific temperatures was studied by the polarized optical microscopy (POM). The results suggest that the spherulites’ morphology depends strongly on the temperature. When the isothermal crystallization temperatures increase from 190 to 225 oC, the spherulites’ morphology continuously changes in the following order: nonbanded → regular banded → serrated banded → nonbanded spherulites. Furthermore, the band spacing increases with the crystallization temperature. Heating the banded spherulites will cause them melt as well as the changing of the bandings, especially the bandings changes in the following order: clear → faint → clear → disappear in a certain range of temperature, which is proposed for resulting from a lamellar melting-recrystallization-remelting mechanism.
Blue Light Emission from a Rod-Like Liquid Crystal
Authors: Zhai Bao Gai , Huang Yuan Ming
Published: January 2010

A rod-like liquid crystal 4-butoxybenzylidene-4'-octylphenylamine was synthesized. The molecular structure and the liquid crystalline phases of the synthesized compound were characterized with the nuclear magnetic resonance spectroscopy, the differential scanning calorimetry, and the polarizing optical microscopy, respectively. The absorption measurement shows that the dilute tetrahydrofuran solutions of the rod-like liquid crystal absorb photons at about 290 and 330 nm, respectively; while the luminescence measurements indicate that this rod-like liquid crystal can give off intense blue photoluminescence with its dominant peak located at about 430 nm. Using Hückel tight-binding program, we have calculated the electronic structures of the liquid crystal, and the origin of the blue photoluminescence is discussed. Introduction
Electronic Transitions in a Classical Antiferroelectric Banana-Shaped Compound
Authors: Zhai Bao Gai , Huang Yuan Ming
Published: January 2010

The electronic transitions in a classical banana-shaped liquid crystal 1,3-phenylene-bis [4-(4-octylphenylimino) methyl] benzoate have been investigated by measuring its optical absorption spectra in dilute solutions of ethyl alcohol and by calculating its electronic structures with extended Hückel tight binding program. The banana-shaped compound shows strong absorptions at 240, 280, 350 nm, respectively. On the basis of the calculated electronic structures, the three strong absorptions can be assigned to the *, n*, and nn* electronic transitions in this banana-shaped compound.
Research on the Line Distortions and its Causation for Liquid Crystals Modules
Authors: Zhang Ping Jun , Jiang Xin Hua
Published: January 2010

According to the manufacturing procedure of liquid crystals modules (LCM), several display distortions of LCM, such as S line distortion, G line distortion, line short-circuit and cs-open are introduced. Combined with its internal structure and its working principle, key causes and repair methods of these distortions are focused on. The pass rate of the product is improved. A foundation has been laid on research in automated diagnosing systems which based on image processing and circuit parameter diagnosing technology.
Synthesis of Small Silicate Spacers for Ferroelectric Liquid Crystal Displays
Authors: Zhai Bao Gai , Huang Yuan Ming
Published: January 2010

In the presence of the aqueous solution of ammonia, tetraethyl orthosilicate (TEOS) was hydrolyzed in the mixture of ethyl alcohol and water with the results of silica spacers. The spacer morphology and size distribution of the synthesized silica spacers were characterized with scanning electron microcopy and laser light scattering spectroscopy, respectively. Our results demonstrated that the synthesized silica spacers were monodispersed and were in perfect spherical shape with their sizes of about 0.7 m in diameter. The correlation between the spacer sizes and the amount of ammonia catalyst was examined, and the spacer sizes of the silica spacers strongly depended on the temperature of chemical reaction and the amount of catalyst. The diameter of silica spacers could be well controlled by controlling the amount of ammonia catalyst, and uniformly distributed silica spacers were produced. Behavior of the miscibility of the silica spacers with a nematic liquid crystal was examined.
Selection of Voltage and Spectral Range in Liquid Crystal Gating
Authors: Liu Han Cheng , Yu Hua Wa , Yan Xiang An , Wu Jun Fang
Published: January 2010

Liquid crystal device (LCD) used as spatial gating apparatus has a lot of new using at low light detecting, imaging spectrum and so on. Since LCD's lattice characteristic, it can come true point gating, local field gating and whole surface gating. It can carry out point-by-point control and feedback of imaging cooperating with CCD detector. Some characteristics of we used LCD, LCX023CMT (SONY), have been detected in order to use conveniently, those include spectra transmittance and which’s changing with gating voltage. The results show that when incident wavelength more than 650nm, this LCD couldn't be used as spatial gating because of polaroid's extinction ratio becoming worse; LCD can modulate the incident light from 400 to 650nm, and the modulates of wavelength range, extent and linearity were related to the modulate voltage clearly. The results indicate that LCD modulates the incident light better and better at voltage more than 2.5V for 550nm; the action modulated become linear with voltage approximately; the modulate extent goes to saturation at voltage more than 5V, and the spectral range modulated is steady in 400-650nm. At voltage more than 5V, transmittance of spectrum is a horizontal beeline almost with incident wavelength range from 400 to 650nm. This indicates that transmittance of spectrum in this range is same, and liquid crystal has none selectivity in colored light. As a result, there is no chromatism between transmitted and incident light. However, because that there is lower transmittance, the reflected light can be used which can ensure not only effective using ratio of light, but also the consistency between reflected and incident light.
Fabrication of Pixel Array Type FED Device with Carbon Nanotube Emitters
Authors: Li Yu Kui , Xing Wen Sheng
Published: January 2010

Because of better field emission characteristics, carbon nanotube was a suitable and excellent cathode material for use in the field emission display device. The screen-printing process was adopted in the course of device fabrication for decreasing the manufacturing cost of the pixel array type field emission display. The new simple-structure flat panel display device with carbon nanotube emitters was reported. The design and fabrication process of pixel array cathode structure were also presented. The silver slurry was screen-printed to form the conducting layer, and the insulation slurry was used to form the high quality insulation layer and covering layer, respectively. The whole display device was vacuum-packaged and developed. The fabricated pixel array type field emission display exhibited better field emission performance and adequate brightness.
Green Aluminate Phosphors Used for Information Display
Authors: Guo Ye Tang , Huang Yuan Ming
Published: January 2010

Well known long-persistent phosphorous strontium aluminates were synthesized by conventional combustion method in a furnace at about 600oC. By incorporating the obtained phosphorous strontium aluminates into organic host polystyrene, we prepared the organic-inorganic composite material (i.e., phosphor-polystyrene) which could be cast into flexible and green-light- emitting films. The morphology of the obtained phosphorous strontium aluminates and the phosphorescence of the organic-inorganic composite films were characterized with the scanning electron microscopy and the fluorescence spectroscopy, respectively. Our results show that the organic-inorganic composite films can be used as green-light- emitting roll-able screens in the industry of information displays.
Research of the Application of Virtual Machine Manufacturing Technology Based on Internet
Authors: Wang Xiao Jun , Xiao Zhong Yue
Published: January 2010

With the use of virtual manufacturing technology, machine tool enterprise shortens the product design and manufacturing cycle, reduces the cost of the product development and improves the ability of the product in response to rapid changes in the market. With the use of the computer emulation and virtual reality technology, and the computer network, machine tool enterprise enhances the ability of decision-making and control at all levels of manufacturing process. This paper analyzes the key technologies to the virtual machine manufacturing and puts forward three models of the virtual machine manufacturing.
Study on the Gloss of Polyurethane Water-Based Ink
Authors: Fang Chang Qing , Zhou Shi Sheng , Zhang M.R. , Ren P.G.
Published: January 2010

With the advantages of no pollution and no poison, the water-based ink, as a new type of green packaging material, is especially applicable to the food, medicine and drink packaging. However, the traditional domestic water-based ink, featuring some disadvantages in the properties of stability, gloss and so on, increasingly evolves into an enormous obstacle to the widespread application of the packaging and the rapid development of the whole industry. In this paper, the polyurethane resin is adopted to replace the ordinary binder resin in the experiment of the water-based ink, and the gloss of the polyurethane water-based ink is also studied. It is shown that the gloss of water-based ink is influenced by the dispersion of pigment, water content and surface tension of water-based ink system, hydrotropic agent and some other factors.
Research on Color Space Conversion Model between XYZ and RGB
Authors: Li Xin Wu
Published: January 2010

Color space conversion for color digital camera is a key and difficult technique in the color reproduction information optics. A new color space conversion model based on subsectional fitting to correct color conversion error camera image is presented. First, color error sources and color rendering mechanism are analyzed in theory; then the paper takes standard color target for experimental sample and substitutes color blocks in color shade district for complete color space to solve the difficulties of experimental color blocks selecting; third the model uses subsectional fitting algorithm to built three dimension color conversion curve to correct color conversion error; Finally the experimental results show that the model can color space conversion accuracy of color digital camera and can be used in color conversion for digital camera practically.
An Analysis for Ground Diffraction about Detecting beyond the Horizon Using Television-Based Bistatic Detection System
Authors: Guo Qiang , Li Yu Kui , Gao Bao Ning , Tao Ran , Zhou Si Yong
Published: January 2010

Analysing the characteristics of a television transmitter carefully, the paper compares the television-based bistatic radar with the conventional monostatic and bistatic radar on targets detecting beyond the horizon in some given direction. In the light of the effect of ground diffraction produced by electromagnetic wave propagation on different radar ranges, it is shown that television-based bistatic radar has a potential advantage over conventional radar in targets detecting beyond the horizon because of its particular advantages in height gain and diffracting efficiency. At the same time, we have an in-depth study which is the decisive factor on radar ranging, height gain or diffraction effect, conduct an effective method of how determine the optimal wavelength so as to get the maximum radar detecting range.
Multi-Channels PCs Polarization Filter and Analysis of Influence Factors
Authors: Shi Jian Ping , Huang Yuan , Wen Song Ling
Published: January 2010

We present a multi-channel PCs polarization filter, which overcomes the disadvantage of the low channel numbers in the existing filters. The multi-channel PCs polarization filter is based on one dimensional photonic crystal with a defect layer. The simulation results by transfer matrix method show that the filter can realize more than four filtering channels with the separation degree better than 0.95 and the transmission rate more than 50%, and the channels are almost distributed evenly. We also analyze the influence factors of filter performance. The results show that defect layer thickness of photonic crystal determines the number of filter channels. The thickness and number of unit layers of photonic crystals does not affect the number of filter channels, however it can adjust the location of central wavelength for each filter channel.
Study on Polyurethane/Polyurethane Emulsion Water-Based Ink
Authors: Fang Chang Qing , Zhang M.R. , Li Tie Hu , Zhou Shi Sheng , Zhao S.J.
Published: January 2010

In this paper, polyurethane and its emulsion, with appropriate additives added, are used as binder to replace the traditional resin binder in the experiment of making water-based ink. And then the main mechanism of each component is analyzed. It is indicated that the emulsion makes the binder soak through the paint faster and infiltrate into the particles pores of pigments aggregates by reducing the tension on the surface of monomer and water. Thickener can enhance the viscosity of ink and promote the well-proportioned dispersion of pigment mainly by making the water-based ink form a network on the structure. The surface-active molecules, forming "a protective shell" on the surface of paint, effectively strengthen the affinity between the binder and pigment to make them be fully reconciled and ultimately improve the performance of water-based ink.
Synthesis of Liquid Crystalline Epoxy Resin p-BDEPB and Cure Kinetics with 3-MeTHPA
Authors: Gao Jun Gang , Zhang Cai Yun , Huo Li , Zhang Yuan Yuan
Published: January 2010

A liquid crystalline epoxy resin of p-biphenylene di-4-(2,3-epoxypropyloxy)benzoate (p-BDEPB) was synthesized from allyl bromide, 4-hydroxy ethyl benzoate and 4,4-dihydroxybiphenyl. Its structure and liquid crystalline behavior were characterized by DSC, 1H-NMR, FTIR, POM and XRD. The results are shown that this compound is smectic liquid crystalline.The melting point of p-BDEPB is 210 oC and clearing point is over 300 oC, the epoxy value is 0.312 mol/100g. The average curing Ea of p-BDEPB/3-methyl-tetrahydrophthalic anhydride (MeTHPA) system is 97.2kJ/mol. The gel point of cured-system Tgel is 89.0 oC, curing temperature Tcu is 132.5 oC and finishing temperature Tf is 146.5 oC. The curing reaction can be described by the autocatalytic Šesták-Berggren (S-B) equation, the two reaction orders m and n is 0.23 and 0.74, respectively.
Design, Synthesis and Properties of Asymmetric Substituted Coronene Derivative as Discotic Liquid Crystal
Authors: Wang Wen Guang , Liu Xu Ying , Liu Ling , Pu Jia Ling
Published: January 2010

Asymmetric substituted coronenes as building blocks for preparation of materials used as functional molecular devices in the fields of self-organization, organic light-emitting diode, photovoltaic solar cell and field effect transistor are easily converted to potential interesting coronene’s derivatives. A novel kind of derivative of dibenzocoronene with perylene tetracarboxdiimide as discotic liquid crystal with two kinds of soft and long chains was designed and synthesized. Its structure was confirmed by 1HNMR and IR. Its UV-vis was measured. Its properties as discotic liquid crystal are investigated in progress.
The Hydrogen Evolution Reaction on Electrolytic Nickel-Based Coatings Containing Metallic Molybdenum
Authors: Popczyk Magdalena
Published: January 2010

Ni-Mo and Ni+Mo coatings were prepared by electrodeposition under the galvanostatic conditions, in such a manner that the coatings contain the same quantity of molybdenum. The electrochemical activity of these coatings was studied in the process of hydrogen evolution reaction (HER) from 5 M KOH solution using steady-state polarization and electrochemical impedance spectroscopy (EIS) methods. Basing on the results of EIS measurements, the rate constants of the HER as well as the surface roughness factors were determined. It was found that Ni+Mo composite coating is characterized by enhanced electrochemical activity towards hydrogen evolution as compared with Ni-Mo alloy coating. Improvement of the electrocatalytic performance of Ni+Mo composite coating could be attributed to the increase in its real surface area as well as to the catalytic effect in points of contact of molybdenum and nickel matrix. Thus obtained composite coating may be useful in application as electrode materials for the hydrogen evolution reaction.
Cordierite Foam Supports Washcoated with Zeolite-Based Catalysts for Volatile Organic Compounds (VOCs) Combustion
Authors: Silva Elisabete R. , Silva J.M. , Oliveira Fernando A. Costa , Vaz M. Fatima , Ribeiro M. Filipa
Published: January 2010

Reticulated cordierite foams produced by a direct foaming method were successfully washcoated with platinum-based zeolite catalysts. For comparison purposes, commercial cordierite monoliths were also washcoated. The effect of the structural properties on the fluid dynamics and catalytic behaviour for the toluene combustion were evaluated. Foam supports revealed highest performances, in terms of conversion into CO2, when compared to conventional honeycomb monoliths. The experimental results suggest that the catalytic behaviour is critically dependent on the fluid dynamics provided by structural characteristics of the supports, such as porosity, density and size of pores. The randomness and tortuosity of foams enhance reactant mixing, as it was evidenced by the higher axial and radial dispersions of the gas flow across the foam structure. This leads to better mass and heat transfers in the reaction system, thus improving the catalytic behaviour.
Zn-TiO2 and ZnNi-TiO2 Nanocomposite Coatings: Corrosion Behaviour
Authors: Gomes Augusto , Almeida I. , Frade Tania , Tavares Ana C.
Published: January 2010

This work presents the corrosion behaviour of the as-prepared of Zn-TiO2 and ZnNi-TiO2 films in neutral Na2SO4 solution and a first attempt to correlate with their composition, morphology and structure. The films were prepared by galvanostatic pulse method onto steel electrodes, at room temperature. The X-ray diffraction study revealed that the ZnNi alloy consists of a homogenous Ni5Zn21 phase and that the preferred crystallographic orientation of Zn deposits changes in the presence of TiO2. The SEM results show that the morphology of the metallic coating is function of the metal phase composition and become more porous in the presence of 1.5 wt% TiO2.The corrosion parameters for the nanocomposite coatings were compared with those of pure Zn and ZnNi electrodeposits, and the ZnNi-TiO2 nanocomposite coating shows the less cathodic corrosion potential.