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Based on modified natural gas direct injection engine, we studied the impacts of ignition timing and jet timing on natural gas engine start process in this paper. The results shows that: when the first jet ignition occurs in the first compression stroke, the engine reaches idle speed 400rpm fastest; as the jet timing is delayed, emissions during engine start is gradually reduced, but when the jet late, HC surge occurs, the emissions deteriorates; with the ignition advance angle increasing, the engine speed growth accelerates, the peak moves forward; with the ignition advance angle increasing, HC emissions peak increases, the peak moves forward.

TiC/Fe composites were successfully fabricated in situ by self-propagating high temperature synthesis (SHS) technology. The effect of Fe content on the microstructure of the synthetic products was discussed. Results showed that the SHS products of Ti-C-30wt%Fe system were mainly composed of TiC and Fe as well as a few Fe2Ti.Spherical TiC particles with 2-3μm distributed on the Fe matrix uniformly. With the increase of Fe content, the combustion temperature reduced, resulting in the decrease of growth rate of TiC particles.

Hydrajet fracturing connects hydraulic perforating and hydraulic fracturing together, realizing precise perforating and fracturing without packers, and it reduces the pollution to the reservoir. Initiation pressure is a very important factor during hydrajet fracturing operation. Through contrast studies of hydraulic fracturing and hydrajet fracturing, comparing their similarities and differences, analyze the initiation mechanism of hydrajet fracturing in open deviated wellbore. The derived formula of initiation pressure can help guide parameter optimization during fracturing.

In order to modify the properties of the epoxy composites, an alkali catalyzed biphenyldiol formaldehyde resin (BPFR) was synthesized and used to cure epoxy resin (ER). γ-Glycidoxypropyl trimethoxysilane (KH-560) was used as a reinforcer of the composites. Laminates of the BPFR/ER fiberglass reinforced composites with different (KH-560) contents were prepared. The influence of the KH-560 content on the glass transition temperature (Tg) and thermal degradation properties of the composites was researched by dynamic mechanical analyzer (DMA) and thermogravimetric analysis (TG). The mechanical, electrical properties of the composites were determined. The results showed that the interfacial bonding strength between resin matrix and fiberglass can be efficiently improved with the presence of KH-560. When the ratio of BPFR and ER is 3 : 7, the content of KH-560 is 5 ~7 wt%, the impact resistance of the fiberglass reinforced composites is 61.35~78.59 kJ/m2, the tensile resistance is 150.37~162.54 MPa, which are all 30 % higher than that of no added; The dielectric constant ε and dielectric loss tanδ of the composites is between 0.50~0.68 and between 0.008~0.01, respectively.

The core-shell nanocomposite particles were prepared from acrylate monomers and octavinyl polyhedral oligomeric silsesquioxane (V-POSS) by emulsion polymerization. The structure and properties of emulsion and latex film were characterized by FT-IR, dynamic mechanical analysis (DMA) and TEM and laser particle diameter analyzer (LPDA). The results showed that the V-POSS/polyacrylated (V-POSS/PMA) composite latexes was prepared and the diameter is about 36.1 nm when added 5wt% V-POSS. DMA results showed that the mechanical loss (tanδ) peak temperature (Tp) of the film enhance with increasing V-POSS content and had the best high Tp at 88.4°C for added 7 wt% V-POSS, which increased 7.8 °C than had not V-POSS. Thermogravimetric analysis (TGA) showed that the addition of V-POSS can increase the thermal decomposition temperature and improved the thermal stability of polyacrylate.

Sorbus sibirica fruits, popularly consumed as tea, is believed to promote healthy, relieve a cough. The literature reporting pharmacological studies related to Sorbus sibirica is very limited. Thus, The antioxidant activities of extracts from Sorbus sibirica fruits were evaluated using various in vitro assays including total flavonoid contents, total antioxidant activity, reducing power, lipid peroxidation inhibitory activity, scavenging hydroxyl and superoxide anion free radicals activity, and protective effects against DNA and protein damages. We selected the process of ultrasound-assisted extraction for total flavonoids from Sorbus sibirica fruits according to the extraction rate of total flavonoids. Results showed that the content of total flavonoids was 0.82 g per 100 g dry fruits sample obtained with ultrasound-assisted extraction method. The extracts exhibited strong scavenging capability with respect to hydroxyl and superoxide anion free radicals, and effectively inhibited the lipid peroxidation of polyunsaturated fatty acids. They also had good reducing power and protection against DNA and protein damage. Therefore, they might offer an important source of effective natural antioxidants in the food and cosmetic industries.

In traditional frequency synthesizers, there is a frequency synthesis module for every output channel, so there is crosstalk between output channels. The more the output modules, the more is the crosstalk. Deeply researching shows that the crosstalk between output modules has most of the influence on output stray [2,. To improve the output stray, a new scheme of designing frequency synthesizer with low output stray is given in this paper. In the new scheme, there is only one frequency synthesis module for all outputs. The output of the module is divided into several outputs by the power divider. Then these outputs directly input to the output modules. In this way, the crosstalk between the frequency synthesis modules can be effectively avoided, and the output stray can be significantly reduced. On the other hand, the volume and the cost of the synthesizer is reduced. Simulation result shows that the new scheme can meet the requirements of low output stray.

In order increasing properties of polyurethane acrylate coating, the epoxy resin/ polyurethane acrylate coating was prepared by UV and thermal dual curing with diphenyliodonium salt. The curing reaction and kinetics was investigated by UV-radiation and DSC, and the influence of the siloxane of methylacryloylpropyl-trimethoxysilane (MAPTMS) content on the properties of coating was determined by DMA and other physical methods. The results showed the hardness and glass transition temperature Tg of the coating film increased with the increasing MAPTMS content and the coating has good adhesion. When the content of MAPTMS reach 12 wt%, the Tg is the highest, which is 8.2°C higher than the before; When the triethylene glycol divinyl ether (DVE-3) can change the reaction from UV free radical/cationic reaction into thermal radical/cationic reaction, and can be described by autocatalytic Šesták-Berggre model (S-B) and the average activation energy Ea is 70.55 kJ/mol.

Low-field nuclear magnetic resonance (LFNMR) is a rapid, nondestructive analytical method which has been proved to be attractive for its application in brittle and easily compressed coals. In this paper, the relationships between NMR parameters and coal pores were analyzed by the NMR measurements of six coal samples with different ranks using AniMR with the resonance frequency of 12.15MHz. Results show that NMR porosity usually compare well to water porosity and be lower than He porosity, and the NMR porosity at echo spacing of 0.3ms sometimes underestimates the coal sample, lower than water porosity by >1 porosity unit. In contrast, the NMR porosity at echo spacing of 0.1ms is acceptable for characterization of coal reservoir. The difference of NMR porosity at different echo spacing may relate to the vitrinite content. Based on the T2c model, the transverse surface relaxivity of coal is calculated and it ranges from 0.25 to 20 um/s, commonly lower than 5um/s. The producible porosity could be a parameter used to estimate coal permeability, however there still needs a lot of work to construct a perfect method for this.

Effect of rotating speed and welding velocity on properties of 6063-3A21 dissimilar Friction Stir weld was experimental studied, results show that too high or too low welding velocity will result in a decrease of the weld strength; effect of rotating speed on weld strength is relatively small. An optimized method for Choosing Friction Stir Welding parameters was proposed, which include three steps, first, fix a rotating speed through experimental analysis; and then find out reasonable ranges of v/w; finally work out the optimized welding speed range.

There exist some mobile node localization algoriths in wireless sensor netwok,which require high computation and specialized hardware and high node large density of beacon nodes.The Monte Carlo localization method has been studied and an improved Monte Carlo node localization has been proposed. Predicting the trajectory of the node by interpolation and combing sampling box to sampling. The method can improve the efficiency of sampling and accuracy. The simulation results show that the method has achieved good localization accuracy.

Parting surface design is the key to mold design. Taking mold design of a component as an example, this paper introduces the implementation of a parting surface design of complex multi-cavity mold supported by the surface technique of Pro/E software.

In this paper, a novel approach based on time-frequency atom decomposition is presented to recognize the radar emitter signals. To decompose the signals into a linear expansion of time-frequency atoms, a fast matching pursuit (MP) algorithm, which is optimized by composite differential evolution (CoDE) algorithm, is introduced. The feature vectors of radar emitter signals are extracted based on the atoms generated in the process of decomposition. The Directed Acyclic Graph SVM (DAGSVM) is selected as the classifier to classify the feature vectors of different radar emitter signals.

In ouder to prepare the waterborne UV-curable polyurethane acrylate coatings, the anionic polyurethane acrylate emulsifier and bisphenol-S eopxy acrylate were synthesized. The curing process, kinetics and properties of waterborone UV-curable epoxy acrylate/polyurethanes acrylate coating were investigated by FTIR, DSC and DMA. The results show that the static initial curing temperature Ti is 52.36 oC, peak temperature Tp is 71.58 oC, the finished temperature Tf is 89.15 oC. The curing reaction can be described by two-parameter autocatalytic Šesták-Berggren (S-B) model.This coating has a better UV-curing property. The dynamic mechanical analysis showed that the glass transition temperature Tg of coating film is 52.70 oC.

Ceramic coatings were successfully fabricated on Mg-7Li alloy in Na2SiO3 electrolyte by microarc oxidation (MAO). The phase composition, formation mechanism and infrared emissivity of the coatings were investigated. Results show that the surface of MAO coating exists some micropores with a diameter of 2-6μm due to electric breakdown. The MAO coating with 13μm thickness is mainly composed of MgO, Li2O2 and Mg2SiO4. The infrared emissivity of the MAO coating is higher than that of bare Mg-7Li alloy, mainly because the coating consisting of ionic crystals has lower lattice vibration symmetry and larger dipole moment.

Microstructure of electromagnetic pulse tungstic electrode argon arc welding (EMP-TIG) welded Mg/Al dissimilar metal joint is studyed using optical microscope, scanning electron microscope, and X-ray diffraction. The results indicate that gas tungsten arc welding can provide Mg/Al joint with excellent microstructure and performance. The welding region is composed of Mg3Al2 phase, α(Mg), β(Li), and MgAl. The weld zone and the Al alloy base materials are well combined. There are massive MgAl phase dendrites in the weld area, which cause the significantly increase of hardness at weld zone. Near the Mg-8Li alloy base metal side of the weld zone, there exists a layer of 100~ 200μm equiaxed region. About 1μm Mg3Al2 reaction layer is distributed between Mg-8Li alloy base metal and the equiaxed grains. This reaction layer and the Mg-8Li alloy base metal, as well as the weld zone of equiaxed grains, have a good combination.

In order to prepare the innocuity polyvinyl chloride (PVC) products, the calcium/zinc stearate was used as the thermal stabilizer of PVC and the polyols were used as co-stabilizer of Ca/Zn stabilizer. The influence of polyols on the stabilization efficiency of Ca/Zn stabilizer to PVC was investigated by Congo red methods. The rheological behaviors and dynamic mechanical properties of PVC were also investigated by rotational rheometer and dynamic mechanical analyzer (DMA). The results showed that different polyols have different influences on the stability, but the pentaerythritol has a good synergy effect with Ca/Zn stabilizer for PVC and pentaerythritol and dipentaerythritol have a lower melt viscosity and good product color.

In order to prepare the innocuity polyvinyl chloride (PVC) products, the calcium/zinc stearate was used as the thermal stabilizer of PVC and the polyols were used as co-stabilizer of Ca/Zn stabilizer. The influence of polyols on the stabilization efficiency of Ca/Zn stabilizer to PVC was investigated by Congo red methods. The rheological behaviors and dynamic mechanical properties of PVC were also investigated by rotational rheometer and dynamic mechanical analyzer (DMA). The results showed that different polyols have different influences on the stability, but the pentaerythritol has a good synergy effect with Ca/Zn stabilizer for PVC and pentaerythritol and dipentaerythritol have a lower melt viscosity and good product color.

In this study, the strain softening behaviors of an overconsolidated silty clay was studied by a ring shear apparatus. The tested results present some different properties with the traditional shear tests. It was found that the silty clay samples with relatively high shear rates are liable to the occurrence of strain softening. With shear rate increasing, both the peak strengths and the post-peak strength reduction become greater. According to the data of deformation and pore pressure measured during the tests, there are two patterns of causing the strain softening of the silty clay. One is related with the contraction of soil specimens; the other is concerned with the generation of negative pore pressure due to the dilatancy of soil body.

Node localization is one of the key technologies in wireless sensor networks,DV-Hop algorithm is wildly usded .The main DV-Hop localization error is the distance between unknown nodes ande anchor nodes.In this paper, The distance geometry constrain in two-dimensional space has been applied to reduce the error of measurement ,which is the distance between unknown nodes and anchor nodes. Simulation results show that this localization algorithm is effective ,which improves the positioning accuracy.

This paper propose a new design of dual-band GPS microstrip antenna by spreading out the patches on the ground plane. With two independent patches, the antenna operates at two frequencies, which are available in different GPS systems. When patches are spread on the ground plane, the beam of radiation pattern shifts away and axial ratio degrades. In this design, two patches are printed on two independent substrates with a compact design, and positions of two antennas are optimized. Finally, above problems are solved with a conductive vaulted base. The design procedure is discussed, and optimized results are presented.

Establish interior flow field model of the control valves under the blocking fault, using the CFD simulation and analysis the internal flow field of the control valve under the blocking and the trouble-free. The research indicates that blocking changes the fluid state of motion, causes the vortex in the valve core, resulting energy loss and reduces valve control performance.

The communication module was designed based on DeviceNet bus technology in this paper, which had the circuit-breaker used in the DeviceNet. So the intelligence of circuit-breaker was improved. Firstly applied PIC18F458 single chip as control chip in hardware design and proposed the power source, dial switch and LED interface circuit design scheme based on DeviceNet protocol specification. Secondly proposed the soft design scheme, included established module and I/O information communication. At last SST-DN3-PCU-1 main station card was 阿applied as network analyzer to analyze the communication data detail.

Fly ash/LLDPE composite material was obtained by using the molten blending. The melting, crystallization and thermal degradation of fly ash/LLDPE blends were investigated. The results indicate that the addition of fly ash increases the molten peak of blends, which shows that fly ash has the function to prevent heat transfer. The addition of the powder of fly ash has prevented the regular spread of LLDPE molecue and has impact on the regular spread when the segmer crystallizes, spreads and moves, which slows LLDPE's crystallization rate, and has an inhibitory action to LLDPE crystalloid's growth; the starting degradation tempreture (T0, 5%weight loss ) of complex system is lower than that of pure LLDPE, but the tempreture at maximum egradation rate increases with the quantity of fly ash increasing.

Benvitimod (3,5-dihydroxy-4-i-propylstilbene) is a novel drug developed for common skin disorders such as atopic dermatitis by Welichem Biotech Inc. in Canada and Celestial Pharmaceuticals (Shenzhen) Co. Ltd. in China. But the ideal synthesis method is not reported so far. Herein an efficient synthesis method which is operated under the mild conditions is reported. According this route, the total yield will reach 40.3 - 48.1% and the benefits of the improved method are easily operating and environment friendly.

The polyacrylate emulsion coating modified by nano-silica was prepared by In-situ method. Tetraethoxysilane (TEOS) was added as the precursor of SiO2 in the late of the emulsion polymerization. The structure and properties of emulsion and latex film were characterized. The results showed that the nano-hybrid silica/polyacrylate emulsion coating with good performance can be prepared by In-situ method. FTIR analysis indicated that the -Si-O-Si- structure has embodied in the coating film. The particle diameter of emulsion is 378nm when nano-SiO2 content is 6% and the dispersing index is 0.164. The mechanical loss peak temperature (Tp) of coating film with 6% nano-SiO2 is 60.6°C which increase 6°C than pure emulsion film. The nano-hybrid emulsion coating has a good performance, such as good acid-alkali resistance and hardness.

The curing, thermal and mechanical properties of bi-component system for bisphenol A epoxy resin (BPAER) modified by liquid crystalline Sulfonyl bis(4,1-phenylene)bis[4-(2,3-epoxypro pyloxy)benzoate] (p-SBPEPB), with 4,4'-diaminodiphenyl ether (DDE) as a curing agent, were investigated. The effect of the different liquid crystalline contents and the heating rate on curing reaction was discussed. The results show that the curing peak temperature decreases, curing rate increases, the glass transition temperature (Tg)and impact strength all increase with adding of liquid crystalline p-SBPEPB when the content is not over 8wt%.

Boron-containing bisphenol-S formaldehyde resin (BBPSFR) was synthesized by formalin method. The structure and thermal properties of BBPSFR were characterized by 1H NMR, FTIR, torsional braid analysis (TBA) and thermogravimetric analysis (TGA), respectively. The results showed that the borate had formed, and the six-member ring containing boron-oxygen coordinate structure also formed during the curing process. The glass transition temperature (Tg) of BBPSFR is higher 104°C than that of bisphenol-S formaldehyde resins (BPSFR); the initial degradation temperature (Ti ) increases about 43°C; thermal degradation rate decrease and thermal stability increase significantly.

The excellent properties of Mg-Li alloys make them suitable light fabrication materials used extensively in many applications. The microstructure and the surface oxide film at different temperature of as-cast Mg-7Li alloy were investigated by optical microscope(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD) and electronic analytical balance. Results showed that Mg-7Li alloy was composed of mainly α phase and β phase. With increasing temperature, the morphology of the alloy surface varied from the formation of a very thin oxide film, large amounts of oxide particles to the thick and coarse film with a mass of cellular protuberances in size of 40-80μm. The ratio of oxidation weight gains rose from 0.08% to 11.58%. The surface oxide film consisted of mainly magnesium oxide(MgO) phase and lithium peroxide(Li2O2) phase, resulting from the reaction of oxygen with Mg and Li. The volume of the oxides on β phase greater than that on α phase led to the formation of cellular protuberance on the surface of Mg-7Li alloy at high temperature.

In order to improve the properties of boron-containing phenol-formaldehyde resin (BPFR), the tetrabromo-bisphenol A epoxy resin (TBBPAER) was used to cure BPFR. The curing mechanism, thermal properties and the fire resistance of TBBPAER/BPFR were investigated by fourier transform infrared spectrometer (FTIR), thermal gravimetric analysis (TGA), torsional braid analysis (TBA) and the oxygen index method. The results show, -OH of -C6H4-CH2OH and -C6H4OH reacts with the epoxy group. With the increase in the amount of BPFR, the thermal properties get better. When the additive amount of TBBPAER is 10 wt%, this material has best thermal stability at high temperature and higher temperature of loss bromine. The glass transition temperature (Tg) is 223.2 °C and the LOI is 68.5.

UV-curable bi-component coating of glycidyl methacrylate (GMA)/polyurethane –acrylate (PUA) modified with the methylacryloylpropyl polyhedral oligomeric silsesquioxanes (MAP-POSS) were prepared. The dynamic mechanical properties and thermal behavior of nano-hybrid coating (GMA/PUA/MAP-POSS) were characterized with dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and the Fourier transform infrared spectrometer (FTIR). The results indicate the three components have very good compatibility and can co-cure in UV-radialization by a free radical polymerization. The addition of MAP-POSS enhanced the thermal properties, the mechanical loss peak temperature Tp is 85.5°C when the amount of MAP-POSS is 10wt%, which is increased by 12.6 °C than the pure system. When the content of MAP-POSS is 20wt%, thermal decomposition temperature in the initial stages was increased by 7 °C than that of the pure GMA/ PUA.

Here a novel procedure to prepare stable (E)-resveratrol nanoemulsion is reported. The optimum (E)-resveratrol nanoemulsion formulation was sifted based on the pseudo ternary phase diagrams and particle size distribution. An optimized prescription was given as (E)-resveratrol 0.35%, EL-40 22.6%, 1,2-propylene glycol 5.03%, IPM 9.21% and water 62.81% (mass ratio), with the mean particle size 47.3 nm. The morphology of the (E)-resveratrol nanoemulsion was characterized by TEM. The test results demonstrate that the nanoemulsion could dramatically improve the stability and release of (E)-resveratrol.

The boron-containing o-cresol-formaldehyde resin (BoCFR) with different amounts of boron was synthesized from o-cresol, boric acid and formaldehyde solution. The curing process of resin was by characterized by FTIR. The thermal properties and dynamic mechanical properties of resin were investigated. The results show that the borate has formed. The BoCFR has a better thermal stablitity. The residual rate of BoCFR is 30-40 % at 900 oC, which is higher about 400 oC than ordinary o-cresol-formaldehyde resin (o-CFR). The maximal mechanical loss temperature (Tp) is higher 30-38 oC than o-CFR. The weight loss of BoCFR can be main divided two stages. The main thermal degradation reaction follows first order kinetics.

Three class of novel liquid crystalline epoxy resins containing azomething groups: N,N’-Bis[4-(2,3-epoxypropoxy)benzylidene]-4,4-diamino-diphenyl ether (p-BEPBDDE), N,N’-Bis[4-(2,3-epoxypropoxy)benzylidene]-4,4-diamino-diphenyl methane (p-BEPBDDM) and N,N’-Bis[(4-(2,3-epoxypropoxy)-benzyliden)-1,4- phenylene diamine] (p-BEPBPD) were synthesized and characterized. The results show that p-BEBDDE and p-BEBDDM belong to smectic texture and melting point is 239.5 and 178 oC, respectively. The p-BEPBD is nematic texture between its melting temperature (Tm) of 192 oC and clearing temperature (Ti) of 238 oC. The curing reaction can be described by Ozawa equation, and the alcohol-hydroxyl group can accelerate the curing reaction and decrease Ea in DSC experiment.

UV-curable bi-component coating of epoxy-acrylate/polyurethane-acrylate modified with polyhedral oligomeric silsesquioxane containing vinyl group (V-POSS), and UV-cured process and kinetics were investigated by FTIR, DSC, and DMA. The results show that this coating has a good UV-curable property, and the two components have very good compatibility and can co-cure in free radical polymerization. The curing reaction can be described by a two-parameter autocatalytic Šesták-Berggren (S-B) model. The modified UV-curable coating has good adhesive strength for steel and hardness. The mechanical loss peak temperature Tp is highest when the content of V-POSS is 60%, which is increased by 5.2 oC than the pure system.

The poly(vinylchloride) (PVC) nanocomposite was prepared by melt mixed of PVC with polyhedral oligomeric silsesquioxanes containing vinyl group (V-POSS). The rheological behavior of V-POSS/PVC nanocomposites was investigated by torque rheometer and capillary rheometer. The influences of composition of blends, shear rate, shear stress on melt apparent viscosity and non-Newtonian index (n) were discussed. The dynamic mechanical properties, mechanical properties and morphology were determined. The result shows that the plastic time of nanocomposites decreases while melt viscosity increases with increasing V-POSS content. V-POSS has a good compatibility with PVC. The nanocomposites have better impact strength with increasing V-POSS content. V-POSS can use as process aid and impact aid at appropriate contents.

The UV-curable unsaturated polyester (UPR) was modified with glycidyl methacrylate and methylacryloylpropyl polyhedral oligomeric silsesquioxanes (MAP-POSS), and the cure kinetics of MAP-POSS/UPR system was investigated by non-isothermal DSC. The result shows that UPR, glycidyl methacrylate and MAP-POSS have very good compatibility and can co-cure in free radical polymerization.The curing reaction can be described by a two-parameter autocatalytic Šesták-Berggren (S-B) model. The average reaction activation energy Ea for 6% and 9% MAP-POSS content is 73 kJ/mol and is lower than 0% ( about 82kJ/mol). The mechanical loss peak temperature Tp of curing nanocomposites increase with increasing MAP-POSS content and has a highest value when MAP-POSS content is 9%, which is 114.1 oC and higher about 12 oC than pure UPR.

Boron-containing bisphenol-A formaldehyde resin (BBAFR) with different amounts of boron was synthesized from bisphenol-A, formaldehyde solution and boric acid. The fiber-glass reinforced laminates were prepared. The thermal, electric and mechanical properties were determined. The results show that the BBAFR has a better thermal stablitity. The residual rate of BBAFR is 18% at 900 oC, which is higher 300 oC than ordinary phenolic resin. The tensile strength of BBAFR fiber-glass laminates is higher 19.07MPa than ordinary phenolic resin fiber-glass laminates. The volume resistivity and surface resistance of BBAFR laminates increased, but the dielectric loss tanδ and dielectric constant ε decreased.

The elongated grain evolution of alumina ceramics doping with Al2O3-CaO-SiO2(CAS), Nb2O5, and 3Y-TZP was studied under pressureless sintering. From in-situ growth elongated grain cooperating with second phase to toughen the alumina ceramics, microstructure and sintering properties were firstly studied systematically. The effect of additives on the alumina ceramics with columnar grain were analyzed by means of TEM, SEM, XRD, etc. Basing on the analyzed sintering process by the principle of dynamics, the elongated grain growth mechanism was further studied.