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An offshore shoal or bar refracts ocean surface waves and causes wave focusing/defocusing on the adjacent beach. Wave focal patterns characterized by alongshore variations in wave height, wave angle, and breaking location induce alongshore non-uniformities of wave setup and nearshore circulation, e.g., rip currents and alongshore currents, in the surfzone. A simplified analytic model for nearshore circulation generated by focused/defocused waves on a planar beach is developed and theoretical solutions are obtained using transport stream function and perturbations in alongshore distributions of wave height and wave angle at the breaker line. The analytic model suggests that alongshore currents are strongly affected by a pair of counter-rotating vortices generated shoreward of the wave focal zone. The vortices are persistent, and their strengths depend on the amplitudes of alongshore variations in wave height and wave angle. The alongshore gradient in wave height tends to intensify the vortices while the convergence of wave angle tends to weaken the vortices. Divergent flows associated with the vortices in the surfzone are intense, strengthening alongshore currents in the downstream of the wave focal zone and weakening alongshore currents or causing flows reversal in the upstream. Alongshore currents are modulated by rip currents associated with the wave focusing/defocusing patterns.

This retrospective study investigated the effects of fascia iliaca compartment block (FICB) as an adjunctive management to parecoxib for pain control after total hip arthroplasty (THA).A total of 72 patient records of THA were included in this retrospective study. All patients received parecoxib and were allocated to either the treatment group (n = 36) or the control group (n = 36). In addition, patients in the treatment group underwent FICB. The primary outcome was pain intensity measured using a resting and moving visual analog scales (VASs). The secondary outcomes were inflammatory factors (interleukin 6 and C-reactive protein) and occurrence rate of adverse events.Patients in the treatment group had better outcomes in the resting VAS (12 hours, P.01; 24 hours, P.01; 36 hours, P = .01; 72 hours, P = .03), moving VAS (12 hours, P.01; 24 hours, P.01; 36 hours, P = .02; 72 hours, P = .02), serum interleukin 6 (P.01), and C-reactive protein (P.01) than those in the control group at different time points. In addition, there were no significant differences in the occurrence rate of adverse events.The findings of this study demonstrated that the effects of FICB as an adjunctive management to parecoxib are superior to those of parecoxib alone for pain control after THA.

Studies have shown that periodontal pathogens can enter the bloodstream, causing a series of reactions that can lead to a variety of systemic diseases. Epidemiological investigations also found a tight correlation between periodontitis (PD) and osteoporosis. This study aimed to further explore the effect of periodontal pathogens on bone volume fraction like bone tissue and mass, and explain the relationship between PD and osteoporosis. Sprague Dawley rats (female, 16 weeks old) were divided into the wild-type (WT) control group (n=9) and PD group (n=9). After eight weeks, periodontal tissues and ligatures, the fourth lumbar vertebra, the femur, the tibia, and blood were extracted and analyzed by micro-computed tomography (micro-CT), hematoxylin and eosin (HE) staining, tartrate-resistant acid phosphatase (TRAP) staining, polymerase chain reaction (PCR), and enzyme-linked immunoassay (ELISA), respectively. We found that the bone mass of the lumbar vertebra, femur, and tibia was decreased in the PD group. The number of osteoclasts was higher in bone tissue in the PD group than in the WT group (P0.05). The levels of inflammatory mediators and type I collagen C-terminal peptide (CTX-1) were higher in the PD group than in the WT group (P0.05), although no significant difference in bone glutamic acid protein (BGP) levels was observed (P0.05). In addition, we detected several periodontal pathogens, such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Fusobacterium nucleatum, in blood samples from rats in the PD group. These findings suggest that periodontal pathogens can enter the blood circulation from periodontal tissue, promote a systemic inflammation response, and subsequently reduce systemic bone density.

In this paper, UV irradiation curing technology is used in the processing and manufacturing of micro structure parts and a micro-injection molding method of UV-curable molding was proposed to process microstructures. The special material for UV light curing injection of microstructural products was developed. The light curing reactivity of the micro injection light curing special material and its effect on the processing molding are studied. The kinetics of light curing reaction of UV curing injecting material were studied by online infrared spectroscopy (RT-IR). The contribution of mono functional monomers to the double bond conversion rate of microstructures is higher than that of high functional monomers. Under the same condition, the mono functional monomer can make the UV curing reaction more complete. Under the same process conditions, the rate of UV curing reaction of high functional monomers is higher than that of mono functional monomers.

The tetracycline (Tet)-off gene expression regulation system based on the TetR-VP16/Top10 construct has not been widely utilized in plants, for its highly expressed TetR-VP16 activator is toxic to some plants and repeatedly replenishing tetracycline to turn off the constitutively active system is a tedious process. To solve these problems, a Tet-off and heat shock (HS)-on gene expression regulation system was constructed in this study. This system is composed of a chimeric transactivator gene TetR-HSF that is derived from a Tet repressor (TetR) and a HS transcription factor (HSF) controlled by a HS promoter HSP70m, and a Tet operator containing hybrid promoter, Om35S, that drives expression of the β-glucuronidase ( GUS ) gene. The resultant system yields a GUS expression pattern similar to that of the HSP70m promoter under inducing temperatures and at 35 and 40°C drives GUS expression to a similar level as the Cauliflower mosaic virus (CaMV) 35S promoter. Further examination revealed that the TetR-HSF and GUS genes were induced by HS, reaching peak expression after 1 and 6 h treatment, respectively, and the HS induction of the expression system could be inhibited by Tet. This system will provide a useful tool for transgenic studies of plants in the laboratory and in the field, including transgene function analysis, agronomic trait improvement, biopharmaceutical protein production and others.

Non-small-cell lung cancer (NSCLC) is a widespread and particularly aggressive form of cancer. Patients with NSCLC and early metastases typically have poor prognosis, highlighting the critical need for additional drugs to improve disease outcome following surgical resection. The present study aimed to determine if Siamese crocodile bile (SCB) had an anti‑cancer effect on NCI‑H1299 human NSCLC cells. The inhibitory mechanism of SCB was examined in cell culture and nude mice. In vitro experimental results revealed that SCB inhibited the proliferation and colony‑forming ability of NCI‑H1299 cells by arresting cell cycle and inducing apoptosis. The loss of the mitochondrial membrane potential and the release of cytochrome c indicated that SCB treatment may lead to mitochondrial dysfunction in NCI‑H1299 cells. At the molecular level, SCB altered the ratio of protein expression of Bax/Bcl‑2 and activated associated caspases, suggesting that intrinsic pathway involvement in the SCB‑induced apoptosis of NCI‑H1299 cells. In the in vivo experiments, intraperitoneal injection of SCB for 4 weeks inhibited xenograft tumor growth by 46.8% without observable toxicity in nude mice. Immunohistochemistry analysis of proliferating cell nuclear antigen and vascular endothelial growth factor also revealed that SCB inhibited cell proliferation and metastasis in NSCLC xenograft tumors. Overall, SCB exerted an anti-cancer effect on NCI‑H1299 human NSCLC cells in vitro and in vivo and may have therapeutic potential for the treatment of human NSCLC.

In this paper, carbon nanotubes (CNTs) dispersion behavior in epoxy resin under synergistic effect of continuous stretching flow and ultrasound oscillation was studied. A small continuous stretching machine which could provide continuous stretching flow for polymer was designed and manufactured for studying the synergistic effect of continuous stretching flow and ultrasound oscillation on dispersive property. Firstly, the influence of different initial phase angle of dual rotor and mixing time on dispersive property were studied by preparing specimens of CNTs/epoxy resin composite under continuous stretching machine. Then, the synergistic effect of continuous stretching flow and ultrasound oscillation on dispersive property was studied with various ultrasonic power and synergistic time. In this study, the morphology of blends was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that initial phase angle of dual rotor and mixing time had great effect on the dispersion of CNTs in epoxy resin. The degree of CNTs dispersion was best when the initial phase angle of dual rotor was 0°, and increasing mixing time could improve the degree of CNTs dispersion. Increasing ultrasonic power and synergistic time were helpful to disperse CNTs in epoxy resin. It demonstrated that the synergistic effect of continuous stretching flow and ultrasound oscillation had obviously effect on the dispersion of CNTs.

Marine Oil spills have become a serious environmental problem, and contribute to severe impacts and economic losses. Fast and efficient cleanup of oil from marine environment is vital. The use of sorbents is one of the most efficient techniques in removing oil from water. In this work, pure polypropylene (PP) ultrafine fibers with 2 μm diameter were prepared by air assisted melt electrospinning device to be used as oil sorbent. Two fiber samples were used in this study, fluffy, cotton like appearance and oriented, cloth like appearance with different porosities. The influence of temperature change on oil/water mixture was studied. Fluffy fibers showed a better performance in sorption capacity. Results indicated that change in temperature was an important factor in determining the sorption capacity of the fibers. Additionally, in contrast to solution electrospinning, melt electrospinning is safer, cost effective and environmental friendly because of solvents elimination.

Water-brone UV-curable polyurethane acrylate was synthesized based on the toluene diisocynate, polypropylene glycol, dihydroxy methyl acrylic acid and hydroxyethyl acrylate. The structure and the influencing factors on the water solubility and photosensitivity of the waterbrone UV-curable polyurethane acrylate were analyzed. Results show that the water solubility of the resin is enhanced with the increasing of the content of hydrophilic group in the resin. The UV-curing rate of the waterborne coating is good by adding the 819-DW photoinitiator. Triethylamine is a good neutralizer in the waterbrone UV-curable system for having 90% neutralization degree.

This paper mainly introduces a new method of preparation of microcellular material, this method can be divided into three stages: kettle with saturation pressure, heating foaming, flattening and calendaring. During the process of supercritical CO2saturated, different materials need reasonable control parameters such as saturation pressure, saturation temperature and saturated time, and the values of saturation temperature and saturation pressure will directly affect the permeability of supercritical CO2. During the process of heating foaming, it needs to strictly control the parameters such as foaming temperature and foaming time, because the bubble density and bubble size are closely related to the two parameters. During flattening and calendaring process, it is important to control temperature and speed of roller reasonably to avoid the phenomena of collapse in bubbles. There are no harmful substances emissions using this method to produce ultrathin microcellular material, which can also protect the environment.

Some polymers like polypropylene (PP), polyethylene (PE), polyphenylene sulfide (PPS) are very hard to be solute in conventional solvents at room temperature, and impossible to be solution electrospun, but they can be easily fabricated into ultra-fine fibers using melt electrospinning. In this study, PP/PVA compound ultra-fine fibers were produced using mlet electrospinning. The effect of PVA content in PP/PVA compound on the properities of resultant fibers was studied. Different plasticizers were added into the compound to find the most effective plasticizer reducing the melt viscosity. It was shown that PP/PVA compound with content of 5% PVA can produce the finest fiber while adding 8% hyper-branched polyester (HBP). In addition, the resultant fibers were made into thin paper using compaction processing, and water absorbability was tested. The results were expected to be used in dyeable PP cloth production and degradable polymer paper production.

This article mainly introduced the structure and the principle of gas barrier of the rubber nano-laminated composite materials with alternating layer structure and excellent gas barrier property. Due to the fact that the barrier resin material was dispersed in matrix rubber evenly and parallelly in nanometer, the phase structure lead to the existence of multipath movement and deep penetration in the composite materials, thus the permeability coefficient of composite materials were reduced significantly. So the rubber nano-laminated composite materials owned excellent gas barrier performance.

The article proposed a kind of new structure for aircraft tire, which includes double firm rings. The aircraft tire of double firm rings was simulated in the instant of landing by finite element analysis, then the simulation result was compared with the one of ordinary aircraft tire. The result indicated that the grounding area and deformation of aircraft tire with double firm rings was less than that of ordinary aircraft tire, which can decrease the rolling resistance and improve high speed performance. In addition, the larger contact pressure located the central region of the contact surface, which can reduce the damage of shoulder rubber and lengthen the life of the aircraft tire.

Polymer melt flowing in the multiplying element and matched die was simulated for the flowing uniformity and pressure distribuiton based on ANSYS. The results of simulation revealed that the height difference between outlet and inlet sections of the channels in multiplying element, the length of transition region and forming region of molding die all affected pressure distribution and velocity uniformity at the outlet.

Based on the advantages of polymer materials over other materials, rotors which are made of the polymer material, are the functional elements of the rotor-assembled strand, and rotate under certain mass flow rate to obtain heat transfer enhancement and online automatic cleaning. The paper carried out numerical studies on heat transfer and friction loss characteristics of the tube fitted with rotors of different spaces. The comparison of the field synergy angle between plain tube and the tube fitted with rotors was also presented in the paper. The numerical data had good agreement with the experimental data. The numerical studies indicated that the field synergy angle of the rotors inserted tube were significantly smaller than that of the plain tube, which validated that the rotors could significantly enhance heat transfer process and had a better comprehensive performance of heat transfer enhancement though extra friction loss was generated. In addition, both the Nusselt number and friction factor of the tube fitted with rotors increased with the increasing space between rotors; the thermal performance factor of the rotors were all higher than 1, which validated the heat transfer enhancement function of the rotors; meanwhile, the thermal performance factor increased with the space between rotors.

In this paper, employing the mixing theory of polymer and the numerical simulation of polymer processing, numerical simulation model for dispersive mixing of solid powders in polymer matrix is studied, and a multi factor accumulative size distribution function is established. Based on this, the dispersive mixing processes of black carbon/natural rubber are studied using three-dimension dynamic numerical simulation, and the influences of operating conditions on the dispersive mixing of black carbon are analyzed. The simulation results show that the final size of solid powder aggregates is depended on the rotational speed of rotors. When the maximum shear stress of polymer flow field is sufficient to overcome the cohesive force of solid powder aggregates, the size of aggregates distribution will be related with mixing time.

In this paper, the 3D flow field and dynamic mixing processing in the continuous mixer with new-type rotors have been studied using finite element software package Polyflow. The influences of continuous mixer process conditions on mixing properties were analyzed by numerical simulation. The results show that the dispersion property is mainly affected by the rotational speed of rotors and the viscosity of polymer. Better dispersion property can be gained as and the viscosity increase. However, the distribution property is mainly affected by feed rate, and the distribution efficiency will reduce if feed rate is too fast.

This work presents the effect of V cut and square cut rotors in circular tubes for turbulent heat transfer using computational fluid dynamics (CFD) modeling. The computational results are in good agreement with experimental data. The obtained results reveal that the use of square cut rotors leads to higher Nusselt number than use of V cut rotors. The results also show that the heat transfer rate, friction factor and thermal performance factor of rotors with square cut increase with the increase of width (a) and depth (b) of rotors’ cut. Square cut rotors with a=b=3 yields higher mean thermal performance factor than those with other width and depth, a=b=1, 2 and the highest thermal performance factor of square cut rotors at a=b=1, 2, 3 are found to be 2.08, 2.11 and 2.13.

Rolling lamination forming of polyvinylchloride light conveyor was simulated using ANSYS12.0/LS-DYNA of FEM software. The filling condition of materials, the change of products’ geometry and the plastic deformation of products during the rolling forming process were studied. And the deforming displacement curves of the product in X direction during the process were also explored and discussed deeply. A simulation method of rolling lamination forming process was established and good results were achieved, which made a contribution to the theory of rolling lamination forming and is meaningful to the mould optimization, process parameters design and product quality control.

In the process of rotational molding, there are two important parameters, temperatures in the rotational molding machine’s oven and in the mold. It is the crux of the evaluation about the molding efficiency and products’ quality to control the time of the temperatures to reach the top. This article puts forward to two time parameters C1, C2 to show temperatures’ change in machine’s oven and in the mold during the molding processing. Besides, these two time parameters are applied to direct the structure design of rotational molding machines and molds. Meanwhile, the theoretical analysis agrees well with the experimental data from the comparison between them. Hence, the efficacy and practicality of the two parameters are well verified.

Absrtract. In this paper, the method of ultrasonic vibration in preparation of multi-walled carbon nanotubes(MWCNTs)/epoxy resin composites was studied. Suspension specimens of MWCNTs/epoxy resin solution prepared by different ultrasonic conditions were compared to find out the influences of operating conditions on dispersion properties. In this study, transmission electron microscopes(TEM) were used to characterize the morphology of the blends and suspension stability was used to evaluate the stability of blends. The results showed that ultrasonic power, ultrasonic time and material quantity have great effect on the dispersion of MWCNTs in epoxy resin solution. Increasing ultrasonic power and time can improve dispersion of MWCNTs, and decreasing material quantity within an appropriate range was helpful to disperse MWCNTs into epoxy resin solution. The results of suspension stability were very similar with TEM results, which demonstrate that suspension stability of MWCNTs/epoxy resin blending could be used as an assistant method to characterize the dispersion of MWCNTs in epoxy resin.

As unfavorable molding defect, weld lines often result in reduced mechanical properties and poor appearance quality of injection molded parts. In this present work, effects of gate locations on the tensile strength of weld lines were investigated by changing the distances between two gates in 10mm, 20mm and 25mm, respectively. Test specimens were prepared with an all-electrical injection molding machine under different process parameters (injection speed, injection pressure and melt temperature). Visualization method and scanning electron microscope (SEM) were employed to further discuss mechanical test results. Study results indicated that tensile strength of injection molded weld lines was lessened as the increase of gate distances. Higher injection speed, higher injection pressure and lower melt temperature induced to lower weldline tensile strength whatever the gate locations were. Study results also illustrated that it was gate location rather than molding conditions had the most decisive influence on the weldline mechanical properties.

Three different kinds of carcass A, B and C for aircraft tires were presented in the article, which is based on the different length of rolling up for carcass cord across the bead ring. And then they were simulated by applying finite element analysis method when aircraft tire was landing in an instant. The simulation results indicated that, the carcass structure of rolling up from the side of bead extending to the other bead (A type) has the minimum deformation, which can reduce the outward of bulge for the side wall and effectively resolve the failure problem for rubber in the sidewall of tire , what’s more , it can prolong the life of aircraft tire to a certain degree and provide good braking performance.

Based on fiber length, fiber orientation distribution and fraction volume, the Halpin-Tsai’ elasticity modulus prediction equation were modified and the elasticity modulus of SGF/TPU composites was experimentally studied. The relationship between the structure and elasticity modulus of SGF/TPU composites was discussed. Results showed that the elasticity modulus of GF-TPU composite rapidly increased as the increasing of fiber volume fraction () and the increasing of the fiber length at the range of 0%-20%. The modified prediction equation of the elasticity modulus fits the test result quite well.

In this article, three kinds of belt named B, C and D type are invented, then their main performance are compared with the other two kinds of belt structures introduced in previous papers. Simulation results showed that B and D-type belts are better than the other three. Comparatively the latter needs less material, its molding process is easier, and the tire body is lighter than B type tire, so in general it can be considered that D-type belt is the best among the five kinds of belt structures.

This study was aimed at understanding how the process conditions affected the dimensional stability of glass fiber reinforced PP by microcellular injection molding. A design of experiments (DOE) was performed and plane test specimens were produced for the shrinkage and warpage analysis. Injection molding trials were performed by systematically adjusting six process parameters (i.e., Injection speed, Injection pressure, Shot temperature, SCF level, Mold temperature, and Cooling time). By analyzing the statistically significant main and two-factor interaction effects, the results showed that the supercritical fluid (SCF) level and the injection speed affected the shrinkage and warpage of microcellular injection molded parts the most.

The new micro-nano lamination technology is developed to produce composite materials with alternating layers structure. After polymer melt enter into the unit passing the process of stream-reverse-superimposed, it produces functional composites with dozens or even thousands of alternating layers, it obtains barrier performance that general multi-layer co-extrusion can not compare with. Equipment cost is low and production process is simple in the barrier composite material production process.

The ability for polymer melt to flow into the microstructure is a crucial factor for successful molding in the microinjection molding of plastic parts. In this study, a simplified analytical model with a direct hot runner nozzle and was constructed to estimate the filling percentage of mold’s cavity. The filling behavior of polymer melt was observed by 3D simulation software Moldflow. The effects of the mold temperature, melt temperature, injection pressure, injection rate, and packing pressure on the filling behavior of polymer melt were investigated. Results revealed that the filling percentage increased with respect to the increase of mold temperature and melt temperature which didn’t exceed its degradation temperature. The injection pressure and packing pressure dramatically influence the filling percentage, and it made no sense to lift the injection speed to fill the cavity when the injection speed reached the relatively high values, and only processing parameter combined available could guarantee the perfect flow and filling for the microstructure.

Melt electrospinning was used to produce PLA superfine fibers. The high spun temperature will lead to serious degradation of PLA. To alleviate the thermal decomposition and obtain superfine fibers at low temperature, sucrrose fatty acid esters (SE) was added to decrease the viscosity of PLA melt. The diameter of PLA including SE was 1.5μm while those of pure PLA was 6.4μm. At the same time, pure PLA melt cost a long time to flow out of cylinder. So SE increased the flowability of PLA melt, which ensured PLA fibers of small diameters were get at low temperature. Spinning load or melt velocity has a direct effect on the relative molecular mass of PLA fibers.

In this paper, the three-dimensional flow field and dynamic mixing processing in the continuous mixer have been studied using the professional polymer processing finite element analysis software package Polyflow. A quantitative evaluation system which consisted of dispersion mixing and distributive mixing was used to evaluate the mixing properties in simulation. Based on these numerical simulations, the influences of rotors’ phase angle and cross-section on mixing properties were analyzed. The results show that the main contribution of phase angles focus on distributive mixing and the main contribution of rotors’ cross-sections focus on dispersion mixing.

In order to get a soft and enclosed vesicle which can endure an instantaneous high temperature and super high pressure the soaking technology of aramid fiber with Room Temperature Vulcanization silicon rubber and liquid polyurethane was studied. Then the performance of the composites was tested. Two kinds of rubber vesicle were made, one with metal valve and another without the valve. Using three-dimension braid method, aramid fiber vesicle was made outside the rubber vesicle. Compression test results of the composite vesicle showed that no-valve rubber vesicle had a good match with the aramid one and endured a very large pressure. It can transfer the liquid pressure from inner vesicle to the outer one, which the aramid fiber has excellent mechanical performance and can endure a very large compression.

Melt electrospinning is a safer, more environmentally friendly and cheaper alternative to solution electrospinning in producing superfine fibers. In this paper, a novel melt electrospinning device was used, which has higher efficiency than conventional equipment. Polypropylene is widely used in many fields and it is difficult to find a suitable solvent for its solution electrospinning at room temperature, so it was chosen in this study. The influences of the electrospinning parameters such as temperature and voltage on the diameter of the spinning fibers have been studied. Temperatures higher than normal processing temperatures were used in present electrospinning system in order to reduce the viscosity of the polymer melt sufficiently. Good quality fibers with smooth surfaces and with diameters mostly smaller than 10 microns were spun successfully. It was found that there was an optimum point for the spinning voltage (70-80KV) and the temperature (230-260°C) to get fine fibers.

The current work is a continuation of Part I. In this part, the simulation results showed that the free tire contour changed measurably after charging and installing it on a steel rim. A distinct stress concentration appeared on the tire shoulder part whenever the tire was charged, touching ground or rolling. When the rotational velocity of the free tire changed, the displacement of the tire crest remains stable while the tire shoulder changes considerably.

Defects such as black spots and yellow surfaces appeared in the process of injection molding light guiding plate as a result of the failure surfaces of the screw and screw tip. To choose and optimize the solutions of different surface treatments of the special screw for light guiding plate, the stripping performance testing platform was established. The experimental results showed that TiN and TiAlN or similar coatings by physical vapor deposition could significantly reduce the adhesion force between polycarbonate (PC) and different coatings. Through surface topography analysis of diversified coatings with SEM and AFM, TiAlN coatings represented the excellent surface quality of its smoothness, continuum, and low surface wave. To enhance the bonding force between the molding screw and coatings, TiAlN/Cr and TiAlN/Ti multi-films was developed which owned much more firm bonding force than TiAlN and good surface quality to be suitable for the special screw for manufacturing light guiding plate.

In order to improve the dispersion homogeneity and stabilization of multi-walled carbon nanotubes (MWNT) in epoxy resin, the effect of different surfactants such as hexadecyl trimethyl ammonium bromide (HTAB), sodium dodecyl sulfate (SDS), oleic acid, Triton X-100 and BYK-9077 on the dispersion of MWNT were investigated. Suspensions of MWNTs/epoxy resin with various surfactants were prepared by ultrasonic agitation. Dispersion homogeneity of MWNT in epoxy resin was evaluated by transmission electron microscopy (TEM), and dispersion stabilization was evaluated by stationary observation. The results show that dispersion properties were not improved by HTAB, while they were improved incoordinately by SDS, oleic acid, Triton X-100 and BYK-9077. Suspensions of MWNTs/epoxy resin with HTAB, SDS, oleic acid and Triton X-100 were all delaminated quickly, it means, dispersion stabilization were not improved by these surfactants. BYK-9077 was the only surfactant which enhanced the dispersion homogeneity and stabilization of MWNTs/epoxy resin significantly. Based on this research, various weight ratios of surfactant BYK-9077 to MWNT were studied. The experimental results show that the dispersion system could reach a balance state when the ratio of surfactant BYK-9077 to MWN was 2.

Injection molding visualization is the experimental method of direct observation on the melt filling behavior in the mold cavity. By using developed visualization system, the influence of mold structure design on the injection molding product’s defects, such as jetting and weld were studied in this paper. The forming process of jetting was observed by the visual method, and results show that it is useful to avoid jetting by locating gate correctly. According to the generation of weld line in single gate cavity, an improved measure to adjust the weld locations by adding overflow traps was proposed. The result indicates that the overflow trap is good for adjusting weld location and makes the defects appear in the unimportant points of surface. Another experiment on the forming process of weld line in two-gate cavity with setting different distance parameters were carried out. The result shows that increasing of gates distance may significantly affect the performance of weld line.

Pressure-Volume-Temperature (P-V-T) properties of two amorphous polymers (ABS and PS) were measured by an on-line testing measurement in the temperature ranges from 20 to 150 °C and pressures from 20 to 120 MPa. The on-line testing measurement is based on an injection molding machine (IMM), and it can be used to get P-V-T data of polymers directly with a special testing mold under normal processing conditions. The experimental P-V-T results of amorphous polymers under industrial processing conditions were presented. A new modified two-domain Spencer-Gilmore equation of state (EOS) was developed. The P-V-T properties were correlated by the modified Spencer-Gilmore EOS and a modified two-domain Tait EOS, showing a good agreement with measurements. The effects of sample forms were investigated. A sample with large length diameter ratio is the best one to be measured.

While the transfer from filling to packing is particularly crucial during injection molding, the transfers from packing to holding and holding to screw recovery also significantly affect part quality. In this study, the control of the transfer from holding to screw recovery, that is the control of the end-point of the holding phase, was examined. The holding end-point control by time, cavity pressure and cavity temperature were presented. The purpose of this study was to validate the feasibility of the control methods of holding end-point by cavity pressure and cavity temperature. The qualities of injection-molded parts, weight, will serve as measures to probe their process capabilities. Recently found to be a good indicator of product quality, both cavity pressure and temperature profiles are applied here to obtain more precise control. Change of mold temperature was specially considered. After the experimental verification is conducted, the results reveal that the innovative holding end-point control by cavity temperature yields a more uniform product weight with mold temperature. It proved that the holding end-point control by cavity temperature can be used to obtain the optimum holding time and accommodate the product weight to the change of mold temperature, which is the other holding control methods cannot obtain.

The light guide plate is an important element of the LCD backlight module which demands a certain degree of transparency and uniformity of gray. The defects such as black spots and yellow surface appeared when the light guide plate was processed by domestic equipments. The main problem was caused by the plasticization unit. The Influencing factors of performance for polycarbonate (PC) special screw were discussed in this paper. The conveyance capacity of melt in the metering zone of injection screws with different flight width and channel depth was analyzed by POLYFLOW software. In order to obtain high surface hardness, corrosion resistance and smoothness of PC special screw, surface coating processing was the key point for injection molding light guide plate. Moreover, the peel strength of PC with different coating processing metallic block was tested and measured. he experimental results of the analysis showed that the nickel-tungsten alloy plating and physical vapor deposition can significantly improve stripping properties, corrosion resistance and smoothness. The influencing factors of coating and PC materials’ stripping were analyzed. Through industrial testing, the defective rate of light guide plate had been greatly reduced with physical vapor deposition compared to the screw with hard chromium plating.

The purpose of this study was to investigate the expression of pituitary tumor transforming gene (PTTG) and basic fibroblast growth factor (bFGF) in oral squamous cell carcinoma (OSCC) and tongue cancer cell line Tca8113, as well as their effects on each other. We detected PTTG protein and bFGF in OSCC tissues from 56 cases using the streptavidin-biotin peroxidase (S-P) method; additionally, after being treated with different concentrations of anti bFGF or PTTG antibody, PTTG or bFGF expression in Tca8113 was examined by immuno-cytochemistry. The results were as follows: (1) Positive rates of PTTG protein and bFGF were 78.2% and 67.3% in OSCC, respectively, which were significantly higher than those in normal mucosal tissues (P

The effect of ethylene–propylene–diene monomer rubber (EPDM) as an additive on the abrasion resistance of a thermoplastic polyurethane (TPU) resin was investigated. The mechanical properties and microstructure of the resultant TPU/EPDM composites were evaluated, and the surface morphology of the composites after abrasion testing was examined. The results showed that the addition of EPDM greatly improved both the mechanical properties and abrasion resistance of the TPU resin. A TPU/EPDM composite with 8 wt % EPDM demonstrated the highest tensile strength, the largest elongation at break, and the best overall performance. The abrasion of this composite was 27 mg, whereas that of the pure resin was 73 mg. With the further addition of EPDM, the abrasion resistance of the resultant composites decreased, whereas the viscosity increased. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

The filling process of plastic precise gear is simulated by CAE software and the factors that influence injection molding accuracy in single cavity mold are discussed in this paper. With the assistant of visualization technology, the mechanism of filling unbalance which influences efficient injection molding was especially studied. The model of filling unbalance was supposed that was verified experimentally by visualization technique. It is clarified that the mechanism of filling unbalance results from dissymmetrical temperature distribution on the cross-section of runner, which is strongly influenced by the shear heat and the cooling process in the runner. At the same time, a new method was proposed for improving the filling imbalance by applying appropriate injection molding process without any changes in runner shape of multi-cavity mold.