Crystal Growth and Crystallization Time Scales of the Panzhihua Layered Intrusion:Constraint from Crystal Size Distribution

The Panzhihua layered intrusions is generated closely related to the Emeishan LIPs.This paper analyzes the spatial distribution of plagioclase and pyroxene.The quantitative texture analysis of 2209 plagioclase shows that the characteristic length of plagioclase is 0.54 to 0.96 mm,the intercept variation range is large,from-0.67 to 0.96,and the slope is-1.85 to-1.04,the Aspect Ratio shows from 1.84 to 2.59 and fractal dimension D is 1.908–1.933.The quantitative texture analysis of 2342 pyroxene shows that the characteristic length of pyroxene is 0.38–0.64 mm,the intercept shows from 0.46 to 2.26,The slope ranges from-2.6 to-1.47,the Aspect Ratio value varies from 1.53 to 1.71,the fractal dimension D is 0.93 to 1.13.All the CSDs results of the Panzhihua intrusions indicate that plagioclase and pyroxene form in an open magma system and undergo four replenishment of magma injection.The plagioclase crystals do not grow as the lathlike shape,and the fractal growth leads to complex crystal surface.The plagioclase undergoes deformation compaction during the crystal process,and then is oriented.The pyroxene crystals grow along an approximately triaxial ratio and undergo texture adjustment and small crystal dissolution reabsorption.When all crystals in magma system grows up to 2 mm,the pyroxene undergoes cumulation in the Panzhihua layered intrusions.The plagioclase crystallization time scale is 171.23–304.41 years,representing that the crystallization is the more uniform in central part of the melt.The nucleation density continuously increases during the crystallization process of the magma system.The time scale to reach the final maximum crystal nucleation density is 15.28–58.98 years.

Effect of Melt Mixing Time in Internal Mixer on Mechanical Properties and Crystallization Behavior of Glycidyl Methacrylate Grafted Poly (Lactic Acid)

Glycidyl methacrylate (GMA) was grafted onto poly (lactic acid) (PLA) by melt mixing in internal mixer using dicumyl peroxide (DCP) as an initiator. The results from proton nuclear magnetic resonance (1H-NMR) and Fourier transform infrared (FTIR) spectroscopy indicated that the grafting reaction of GMA onto PLA took place successfully. The impact strength of PLA-g-GMA was significantly higher than that of pure PLA. The crystallinity of PLA, obtained from differential scanning calorimetry (DSC), decreased after grafting. In order to obtain the optimal mixing conditions, the mixing time was varied into 7, 10 and 14 min. The optimum mixing time of 10 min was found to give the optimum mechanical properties of glycidyl methacrylate grafted poly (lactic acid) (PLA-g- GMA). However, the mixing time played no important role in impact behavior of PLA-g-GMA. In addition, the highest crystallinity was obtained with the PLA-g-GMA prepared with the mixing time of 7 min.

Real-time quantitative optical method to study temperature dependence of crack propagation process in colloidal photonic crystal film

A real-time quantitative optical method to characterize crack propagation in colloidal photonic crystal film（CPCF）is developed based on particle deformation models and previous real-time crack observations. The crack propagation process and temperature dependence of the crack propagation rate in CPCF are investigated. By this method, the crack propagation rate is found to slow down gradually to zero when cracks become more numerous and dense. Meanwhile, with the temperature increasing, the crack propagation rate constant decreases. The negative temperature dependence of the crack propagation rate is due to the increase of van der Waals attraction, which finally results in the decrease of resultant force. The findings provide new insight into the crack propagation process in CPCF.

Variation of Calcium Oxalate (CaOx) Crystals in Porang Corms (Amorphophallus muelleri Blume) at Different Harvest Time

Harvest time is assumed to potentially influence shape and size variation of calcium oxalate (CaOx) crystals;therefore it needs to be observed microscopically. This research used porang corms from the second growing period which were planted to produce the vegetative phase of third growing period. These corms were obtained based on the harvest time had determined. The harvest time was determined, i.e. 1) at two weeks before the plants shed (R0 - 1);2) when the plants shed (R0) and 3) at two weeks after the plants shed (R0 + 1). Slides for microscopic observation were obtained from slices on the edge and center of porang corms. Organ slices were cleared using modified clearing method. Parameters observed were the shape and the size of CaOx crystal. The variations of styloid, prism, druse and raphide crystals found in porang corms at the three harvest time were 1, 2, 3 and 37 variations respectively. The variation of CaOx crystals tended to be same in porang corms at three harvest times. The variation of these crystals tended to be static. It is also known that raphide crystal has the greatest variation amount. On the contrary, styloid crystal has the fewest variation amounts. This abundance of a number of raphide crystal variations is possibly due to its role as a defense mechanism in porang corms.

Effect of Nucleating Agent on the Crystallization of Tailings Glass Ceramics Prepared by One-time Sintering

Glass ceramics was made by the one-time sintering method using the main raw material of iron tailings. On the basis of quaternary system of CaO-MgO-Al2O3-SiO2, using DTA, XRD and SEM, the effects of different nucleating agents and mixing amounts as well as heat treatment on the crystallization of railings glass ceramics were studied. The experimental results show that, nucleating agent and heat treatment are two necessary conditions for one-time sintering preparation of tailings glass ceramics namely, only adding nucleating agent or experiencing heat treatment, the quaternary system can not crystallize. The composite nucleating agent consisting of Cr2O3 and TiO2 can further lead to the crystallization of the CaO-MgO-A1203-SiO2 quaternary system at the lower temperature, with the major phase of diopside. In the range of mass content, 0%-4%, crystal intensity and crystal content grow. But when mass content is more than 4%, the crystal size will become coarser and the crystal distribution will be less regular. Different heat treatment regimes do not change the composition of the crystalline major phase in the glass ceramics crystallization of CaO-MgO-Al2O3-SiO2 system. In the range of 30-60 minutes, with the extension of nucleation and crystallization, crystallization degree enhanced, but if the holding time surpasses 60 minutes, the crystallization is worse.

Optical simulation of in-plane-switching blue phase liquid crystal display using the finite-difference time-domain method

The finite-difference time-domain method is used to simulate the optical characteristics of an in-plane switching blue phase liquid crystal display.Compared with the matrix optic methods and the refractive method,the finite-difference timedomain method,which is used to directly solve Maxwell＇s equations,can consider the lateral variation of the refractive index and obtain an accurate convergence effect.The simulation results show that e-rays and o-rays bend in different directions when the in-plane switching blue phase liquid crystal display is driven by the operating voltage.The finitedifference time-domain method should be used when the distribution of the liquid crystal in the liquid crystal display has a large lateral change.

利用Crystal Ball进行基于时间序列的人口预测——以澳门为例

珠三角是我国经济发展最快的地区之一,正值建设进程中的港珠澳大桥对促进香港、澳门和珠江三角洲西岸地区经济的进一步发展具有重要的战略意义。澳门毗邻珠海,其人口数量和结构的变化对珠三角地区尤其是珠海市的经济结构会造成很大的影响。本文以预测澳门未来的人口发展趋势为例,阐述如何利用Crystal Ball软件进行基于时间序列的人口预测,以期对于珠海及澳门未来在加快相关产业转型升级、转变外贸发展方式、加快医疗、养老、教育、房地产、户籍制度等相关方面需求改革与合作等起到一定的借鉴意义。

基于分子束外延技术可控制备Bi原子团簇的研究

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

A Study of Properties of the Photonic Band Gap of Unmagnetized Plasma Photonic Crystal

In this study, the propagation of electromagnetic waves in one-dimensional plasma photonic crystals （PPCs）, namely, superlattice structures consisting alternately of a homogeneous unmagnetized plasma and dielectric material, is simulated numerically using the finite-difference time-domain （FDTD） algorithm. A perfectly matched layer （PML） absorbing technique is used in this simulation. The reflection and transmission coefficients of electromagnetic （EM） waves through PPCs are calculated. The characteristics of the photonic band gap （PBG） are discussed in terms of plasma density, dielectric constant ratios, number of periods, and introduced layer defect. These may provide some useful information for designing plasma photonic crystal devices.

Design, Simulation &Optimization of 2D Photonic Crystal Power Splitter

A very compact (80 - 100 μm2) integrated power splitting devices with two outputs (1 × 2), four outputs (1 × 4) and six outputs (1 × 6) channel has been designed, simulated and optimized for Telecommunication purpose with T-Junction, Y-Junction, PC line defect waveguides integrated with multimode interference block (PCLD-MMI) and multiple line defect PC waveguides (MLDPCW) configurations. The optical modeling of these proposed structures was investigated by finite difference time domain (FDTD) simulation. With the optimization of the parameters (Hole Radius, R = 0.128 μm, Input Diameter, D = 1.02 μm, Input wavelength, λ = 1.55 μm, Substrate Reflective Index, nsub = Si(1.52), Photonic Crystal Material, npcs = InAs(3.45), and Rectangular crystal structure), 1 × 2 for Y-Junction (100%), 1 × 4 for T-Junction (92.8%) and 1 × 6 configuration for MLDPCW (81%) show maximum power transmission.

Modification of the spontaneous emission of quantum dots near the surface of a three-dimensional colloidal photonic crystal

This paper demonstrates experimentally and numerically that a significant modification of spontaneous emission rate can be achieved near the surface of a three-dimensional photonic crystal. In experiments, semiconductor coreshell quantum dots are intentionally confined in a thin polymer film on which a three-dimensional colloidal photonic crystal is fabricated. The spontaneous emission rate of quantum dots is characterised by conventional and time-resolved photoluminescence （PL） measurements. The modification of the spontaneous emission rate, which is reflected in the change of spectral shape and PL lifetime, is clearly observed. While an obvious increase in the PL lifetime is found at most wavelengths in the band gap, a significant reduction in the PL lifetime by one order of magnitude is observed at the short-wavelength band edge. Numerical simulation reveals a periodic modulation of spontaneous emission rate with decreasing modulation strength when an emitter is moved away from the surface of the photonic crystal. It is supported by the fact that the modification of spontaneous emission rate is not pronounced for quantum dots distributed in a thick polymer film where both enhancement and suppression are present simultaneously. This finding provides a simple and effective way for improving the performance of light emitting devices.

Optical Property of LiNbO_3 Crystal Codoped with In, Mg and Fe

In 2O 3, MgO and Fe 2O 3 were doped in LiNbO3 and Czochralski method was used to grow In:Mg:Fe:LiNbO 3 crystals. The OH - extension transmission spectra, light scattering resistance ability, two wave coupled diffraction efficiency and response time of the crystal were measured. Codoping In and Mg in crystal will improve its light scattering resistance ability and response time. Doping In can increase the ability to replace antisite Nb and decrease the doping quantity of Mg. All these are propitious to improve the optical homogeneity of crystal. Doping Fe can improve the photorefractive sensitivity for LiNbO 3 crystal. We discussed the site of In, Mg and Fe in LiNbO 3 crystals and the influence of the absorption peak of OH - transmission spectra on photorefractive property for LiNbO 3 crystal.

Optical properties of the two-port resonant tunneling filters in two-dimensional photonic crystal slabs

We have designed and fabricated two types of two-port resonant tunneling filters with a triangular air-hole lattice in two-dimensional photonic crystal slabs. In order to improve the filtering efficiency, a feedback method is introduced by closing the waveguide. It is found that the relative position between the closed waveguide boundary and the resonator has an important impact on the dropping efficiency. Based on our analyses, two different types of filters are designed. The transmission spectra and scattering-light far-field patterns are measured, which agree well with theoretical prediction. In addition, the resonant filters are highly sensitive to the size of the resonant cavities, which are useful for practical applications.

A novel optical beam splitter based on photonic crystal with hybrid lattices

A novel optical beam splitter constructed on the basis of photonic crystal（PC） with hybrid lattices is proposed in this paper.The band gap of square-lattice PC is so designed that the incident light is divided into several branch beams.Triangular-lattice graded-index PCs are combined for focusing each branch.Computational calculations are carried out on the basis of finite-different time-domain algorithm to prove the feasibility of our design.The waveguide is unnecessary in the design.Thus the device has functions of both splitting and focusing beams.Size of the divided beam at site of full-width at half-maximum is of the order of λ/2.The designed splitter has the advantages that it has a small volume and can be integrated by conventional semiconductor manufacturing process

Main Factors for Affecting Photonic Bandgap of Photonic Crystals

The factors affecting one dimensional （1D） and two dimensional （2D） photonic crystals （PhCs） are systemically analyzed in this paper by numerical simulation. Transfer matrix method （TMM） is employed for 1D PCs, both finite difference time domain method （FDTD） and plane wave expansion method （PWE） are employed for 2D PCs. The result shows that the photonic bandgaps （PBG） are directly affected by crystal type, crystal lattice constant, modulation of refractive index and periodicity, and it is should be useful for design of different type photonic crystals with the required PBG and functional devices. Finally, as an example, a near-IR 1D PCs narrow filter was designed.

New design of high-precision oven controlled crystal oscillator

Combining oven controlled technique,digital compensation,high-resolution frequency difference measurement and self-calibration technique,a new design method of precise oven controlled crystal oscillator（OCXO） is proposed.Fine compensation is made in the vicinity of the crystal temperature inflection point by using the non-real-time temperature compensation strategy,and self-calibration system is integrated in the crystal.The method improves the digital compensated phase noise,simplifies the traditional OCXO development system,reduces the cost and shortens the developing cycle.Experiment results show that with a standard reference signal and self-calibration updated data,the oscillator can work stable and achieve its best performence.The performance index of crystal oscillator had an improvement with one to two orders of magnitude on the basis of original technical index.The method is widely used in the improvement of high-end crystal oscillator and atomic clock.

Syntheses,Crystal Structures and Anticoagulant Activities of Two L-tryptophan Derivatives

Two new L-tryptophan derivatives,（S）-2-（4-acetoxybenzamido）-3-（1 H-indol-3-yl）propanoic acid（I） and（S）-2-（3-acetoxybenzamido）-3-（1H-indol-3-yl）propanoic acid（II）, were synthesized and characterized by FT-IR, NMR and MS. The single crystals were cultivated and determined with X-ray diffraction. It was determined that the two compounds crystallized in monoclinic space group P21. Compound I（C（21）H（20）N2O5, Mr = 380.39） with a = 8.5227（6）, b = 7.8310（6）, c = 15.2527（11） A°, Z = 2, V = 1017.81（13） A°^3, μ = 0.090 mm^-1, Dc = 1.241 g/cm^3, F（000） = 400, the final R = 0.0412 and w R = 0.1170 for all data. Compound II（C（21）H（20）N2O5, Mr = 380.39） with a = 9.5112（5）, b = 9.2197（4）, c = 10.9115（5） A°, Z = 2, V = 952.13（8） A°^3, μ = 0.096 mm^-1, Dc = 1.327 g/cm^3, F（000） = 400, the final R = 0.0377 and w R = 0.1009 for all data. The anticoagulant activities of L-tryptophan derivatives were evaluated by plasma re-calcification time（PRT） and blood concretion four items（APTT, PT, TT and FIB）. The results exhibited that L-tryptophan derivatives showed anticoagulant activity in normal coagulation pathway.

Simultaneous measurements of global vibrational spectra and dephasing times of molecular vibrational modes by broadband time-resolved coherent anti-Stokes Raman scattering spectrography

In broadband coherent anti-Stokes Raman scattering （CARS） spectroscopy with supercontinuum （SC）, the simultaneously detectable spectral coverage is limited by the spectral continuity and the simultaneity of various spectral components of SC in an enough bandwidth. By numerical simulations, the optimal experimental conditions for improving the SC are obtained. The broadband time-resolved CARS spectrography based on the SC with required temporal and spectral distributions is realised. The global molecular vibrational spectrum with well suppressed nonresonant background noise can be obtained in a single measurement. At the same time, the measurements of dephasing times of various molecular vibrational modes can be conveniently achieved from intensities of a sequence of time-resolved CARS signals. It will be more helpful to provide a complete picture of molecular vibrations, and to exhibit a potential to understand not only both the solvent dynamics and the solute-solvent interactions, but also the mechanisms of chemical reactions in the fields of biology, chemistry and material science.

Bandgap characteristics of 2D plasma photonic crystal with oblique incidence:TM case

A novel periodic boundary condition （PBC）, that is the constant transverse wavenumber （CTW） method, is introduced to solve the time delay in the transverse plane with oblique incidence. Based on the novel PBC, the FDTD/PBC algorithm is proposed to study periodic structure consisting of plasma and vacuum. Then the reflection coefficient for the plasma slab from the FDTD/PBC algorithm is compared with the analytic results to show the validity of our technique. Finally, the reflection coefficients for the plasma photonic crystals are calculated using the FDTD/PBC algorithm to study the variation of bandgap characteristics with the incident angle and the plasma parameters. Thus it has provided the guiding sense for the actual manufacturing plasma photonic crystal.

Engineering the light propagating features through the two-dimensional coupled-cavity photonic crystal waveguides

This paper studies the propagating characteristics of the electromagnetic waves through the coupled-resonator optical waveguides based on the two-dimensional square-lattice photonic crystals by the finite-difference time-domain method. When the traditional circular rods adjacent to the centre of the cavities are replaced by the oval rods, the simulated results show that the waveguide mode region can be adjusted only by the alteration of the oval rods＇ obliquity. When the obliquity of the oval rods around one cavity is different from the obliquity of that around the adjacent cavities, the group velocities of the waveguide modes can be greatly reduced and the information of different frequencies can be shared and chosen at the same time by the waveguide branches with different structures. If the obliquities of the oval rods around two adjacent cavities are equal and they alternate between two values, the group velocities can be further reduced and a maximum value of 0.0008c （c is the light velocity in vacuum） can be acquired.