Intensity and mosaic spread analysis from PISEMA tensors in solid-state NMR

The solid-state NMR experiment PISEMA, is a technique for determining structures of proteins, especially membrane proteins, from oriented samples. One method for determining the structure is to find orientations of local molecular frames (peptide planes) with respect to the unit magnetic field direction, B0. This is done using equations that compute the coordinates of this vector in the frames. This requires an analysis of the PISEMA function and its degeneracies. As a measure of the sensitivity of peptide plane orientations to the data, we use these equations to derive a formula for the intensity function in the powder pattern. With this function and other measures, we investigate the effect of small changes in peptide plane orientations depending on the location of the resonances in the powder pattern spectrum. This gives us an indication of the change in lineshape due to mosaic spread and a way to interpret these in terms of an orientational error bar.     

Formation of palladium nanoparticles in poly (o-methoxyaniline) macromolecule fibers: An in-situ chemical synthesis method

We report here a novel in-situ synthetic method for the preparation of poly (o-methoxyaniline) and palladium nanoparticle composite material. Ortho-Methoxyaniline and palladium acetate were used as the precursors; during the reaction o-methoxyaniline was oxidized and forms poly (o-methoxyaniline) and palladium acetate is reduced forming palladium nanoparticles. IR and Raman spectra provide information on the structure of the polymer. The TEM and SEM analysis are used to determine the size of the nanoparticles and the morphology of the polymer respectively.     

SSC-LINAC中APF型DTL的优化设计

A linear accelerator as a new injector for the SSC （Separated Sector Cyclotron） of the HIRFL （Heavy Ion Research Facility Lanzhou） is being designed. The DTL （Drift-Tube-Linac） has been designed to accelerate ^238U^34＋ from 0.140 MeV/u to 0.97 MeV/u. To the first accelerating tank which accelerates ^238U^34＋ to 0.54 MeV/u, the approach of Alternating-Phase-Focusing （APF） is applied. The phase array is obtained by coupling optimization software Dakota and beam optics code LINREV. With the hybrid of Multi- objective Genetic Algorithm （MOGA） and a pattern search method, an optimum array of asynchronous phases is determined. The final growth, both transversely and longitudinally, can meet the design requirements. In this paper, the deign optimization of the APF DTL is presented.     

Optical patterns in spatially coupled phase-conjugate systems

Various pattern evolutions are presented in one-and two-dimensional spatially coupled phase-conjugate systems (SCPCSs).As the system parameters change,different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS.The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries,finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS.Numerical simulations are very helpful for understanding the complex optical phenomena.     

Microfluidic device embedding electrodes for dielectrophoretic manipulation of cells‐A review

Microfluidic device embedding electrodes realizes cell manipulation with the help of dielectrophoresis. Cell manipulation is an important technology for cell sorting and cell population purification. Till now, the theory of dielectrophoresis has been greatly developed. Microfluidic devices with various arrangements of electrodes have been reported from the beginning of the single non‐uniform electric field to the later multiple physical fields. This paper reviews the research status of microfluidic device embedding electrodes for cell manipulation based on dielectrophoresis. Firstly, the working principle of dielectrophoresis is explained. Next, cell manipulation approaches based on dielectrophoresis are introduced. Then, different types of electrode arrangements in the microfluidic device for cell manipulation are discussed, including planar, multilayered and microarray dot electrodes. Finally, the future development trend of the dielectrophoresis with the help of microfluidic devices is prospected. With the rapid development of microfluidic technology, in the near future, high precision, high throughput, high efficiency, multifunctional, portable, economical and practical microfluidic dielectrophoresis will be widely used in the fields of biology, medicine, agriculture and so on.     

基于挥发性组分的气相色谱指纹图谱评价沉香化气片质量

建立了沉香化气片的气相色谱指纹图谱,并结合化学模式识别评价20批沉香化气片的质量。乙醇超声提取20批沉香化气片的挥发性成分,以正十八烷为内标,分析了3个主要组分的含量,且以内标计算其他各组分的相对峰面积,建立了沉香化气片的气相色谱指纹图谱,确定了11个共有峰,得到了各批次样品的相似度,并通过气相色谱-质谱法和对照品比对对10个共有峰进行了指认。将获得的峰面积指纹图谱采用系统聚类分析和主成分分析进行化学模式识别研究,实现了不同批次沉香化气片的区分,发现了造成不同批次样品差异的主要标记物。该方法有效且综合性强,为科学评价与有效控制沉香化气片的质量提供了可靠的参考。     

反应扩散模型在图灵斑图中的应用及数值模拟

反应扩散方程模型常被用于描述生物学中斑图的形成.从反应扩散模型出发,理论推导得到GiererMeinhardt模型的斑图形成机理,解释了非线性常微分方程系统的稳定常数平衡态在加入扩散项后会发生失稳并产生图灵斑图的过程.通过计算该模型,得到图灵斑图产生的参数条件.数值方法中采用一类有效的高精度数值格式,即在空间离散条件下采用Chebyshev谱配置方法,在时间离散条件下采用紧致隐积分因子方法.该方法结合了谱方法和紧致隐积分因子方法的优点,具有精度高、稳定性好、存储量小等优点.数值模拟表明,在其他条件一定的情况下,系统控制参数κ取不同值对于斑图的产生具有重要的影响,数值结果验证了理论结果.     

Event patterns extracted from top quark-related spectra in proton-proton collisions at 8 TeV

We analyze the transverse momentum(p _T)and rapidity(y)spectra of top quark pairs,hadronic top quarks,and top quarks produced in proton-proton(pp)collisions at center-of-mass energys~(1/2)=8 Te V.For p _(T )spectra,we use the superposition of the inverse power-law suggested by the QCD(quantum chromodynamics)calculus and the Erlang distribution resulting from a multisource thermal model.For y spectra,we use the two-component Gaussian function resulting from the revised Landau hydrodynamic model.The modelling results are in agreement with the experimental data measured at the detector level,in the fiducial phase-space,and in the full phase-space by the ATLAS Collaboration at the Large Hadron Collider(LHC).Based on the parameter values extracted from p _(T )and y spectra,the event patterns in three-dimensional velocity(β_x-β_y-β_z),momentum(p_x-p_y-p_z),and rapidity(y_1-y_2-y)spaces are obtained,and the probability distributions of these components are also obtained.     

STUDY ON PARAMETERS FOR TOPOLOGICAL VARIABLES FIELD INTERPOLATED BY MOVING LEAST SQUARE APPROXIMATION

This paper presents a new approach to the structural topology optimization of continuum structures. Material-point independent variables are presented to illustrate the existence condition,or inexistence of the material points and their vicinity instead of elements or nodes in popular topology optimization methods. Topological variables field is constructed by moving least square approximation which is used as a shape function in the meshless method. Combined with finite element analyses,not only checkerboard patterns and mesh-dependence phenomena are overcome by this continuous and smooth topological variables field,but also the locations and numbers of topological variables can be arbitrary. Parameters including the number of quadrature points,scaling parameter,weight function and so on upon optimum topological configurations are discussed. Two classic topology optimization problems are solved successfully by the proposed method. The method is found robust and no numerical instabilities are found with proper parameters.     

宁波服装博物馆设计方案探析

分析了小型专题博物馆在国内外的发展特点和趋势;针对宁波服装博物馆项目的设计实践,从地域文化、空间形态、展陈互动结合、传统现代结合等几个方面提出了小型专题博物馆的创新设计理念和设计方法.