Interactions of breathers and solitons of a generalized variable-coefficient Korteweg-de Vries-modified Korteweg-de Vries equation with symbolic computation

Under investigation in this paper is a generalized variable-coefficient Korteweg-de Vries-modified Korteweg-de Vries equation which describes certain atmospheric blocking phenomenon. Lax pair and infinitely many conservation laws are obtained. With the help of the Hirota method and symbolic computation, the one-, two- and three-soliton solutions are given. Besides, breather and double pole solutions are derived. Propagation characteristics and interactions of breathers and solitons are discussed analytically and graphically. Results also show that the soliton changes its type between depression and elevation periodically. Parabolic-like breather and double pole are depicted. Conditions of the depression and elevation solitons are also given.     

陕北侏罗纪富镜煤和富惰煤分子结构的FTIR，XPS和13C NMR表征

侏罗纪优质煤炭资源为煤制油、制气等清洁高效利用提供了丰富的物质基础,其显微组分以富集惰质组为特征,而镜质组与惰质组大分子结构在很大程度上决定了煤的物理化学性质和工艺性能,进而决定了煤炭资源的综合利用效率及附加值。采集并制备了陕北侏罗纪煤田小保当煤矿和柠条塔煤矿的原煤(XR)、富镜质组煤(XV、NV)和富惰质组煤(XI、NI)样品,利用傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、固体13C核磁共振谱(13C NMR)等手段,结合煤质分析结果,定量表征了不同显微组分富集物分子结构的差异。研究结果表明：XI和NI煤中芳烃结构芳环取代程度低,主要以3个相邻、4~5个相邻的氢原子形式存在,苯环上氢原子较少被其他官能团取代,同时其结构中芳烃C═C骨架振动明显,脂肪结构中亚甲基伸缩振动强度较低,并且甲基含量略高于富镜煤,C═O基团相对含量略高,表明富惰煤有较多含氧桥键相连的芳香结构,其结构中脂族链、脂环基团脱落、断裂以及芳烃富集,支链相对较少且长度较短,芳碳率、芳香度、芳环缩合程度及成熟度较高。XV和NV煤中表面结构中碳的赋存形态“C—C,C—H”,“C—O”的相对含量高于富惰煤,反映其结构中应含较多的芳环取代的脂肪族侧链,XI和NI煤表面结构中氧的赋存形态以“C—O”为主,“C═O”和“COO—”明显高于富镜煤。XV和XI煤的芳碳率分别为57.91%和66.02%,脂甲基碳分别为10.02%和7.84%,质子化芳碳为非质子化芳碳的两倍,XV煤的羰基和羧基碳相对含量较高,两者桥碳和周碳之比分别为0.25和0.40,芳香核结构平均缩合环数分别为2.68和3.03,平均尺寸分别为0.448和0.676 nm,XI煤结构中芳香核以萘和蒽为主,支链化度L_γ分别为0.22和0.19,表明XV比XI存在较多脂肪侧链、饱和环结构,生烃(油)潜力大。     

葡萄糖与甲胺还原胺化产物的高效液相色谱分析

建立了以C18柱、RI检测器,甲醇-水-三氟乙酸为流动相,葡丙胺作内标物,分析葡萄糖与甲胺还原胺化产物1-脱氧-1-(甲氨基)-D-山梨醇纯度的HPLC法.方法具有快速、准确、简便等特点,N-甲基葡糖胺、N-甲基葡糖苷、山梨醇的相对标准偏差分别为1.42%、3.24%、2.45%,回收率分别为95.2%-100.9%、96.7%-123.0%、98.3%-117.0%,检出限分别为33ng、38ng、18ng.     

THz自由电子激光波荡器工程设计

根据波荡器物理参数的要求,主要设计了磁块与磁极的尺寸公差、装配方式、永磁性能指标及永磁测量系统。束流方向上磁块与磁极尺寸公差分别为0.05 mm和0.02 mm,磁块与磁极独立装调,利用亥姆霍兹线圈和磁场积分法测量磁块性能。最后设计了机械与控制系统。其中,横梁与支架形变分别为1.5 m和7.5 m。间隙调节范围18~32 mm,调节精度和锥度分别为0.01 mm和0.015 mm。     

The effects of aircraft on climate and pollution. Part I: Numerical methods for treating the subgrid evolution of discrete size- and composition-resolved contrails from all commercial flights worldwide

This paper provides and evaluates mass conservative, positive-definite, unconditionally-stable, and non-iterative numerical techniques for simulating the evolution of discrete, size- and composition-resolved aerosol and contrail particles in individual aircraft exhaust plumes in a global or regional 3-D atmospheric model and coupling the subgrid exhaust plume information to the grid scale. Such treatment represents a new method of simulating the effects of aircraft on climate, contrails, and atmospheric composition. Microphysical processes solved within each plume include size-resolved coagulation among and between aerosol and contrail particles and their inclusions, aerosol-to-hydrometeor particle ice and liquid nucleation, deposition/sublimation, and condensation/evaporation. Each plume has its own emission and supersaturation, and the spreading and shearing of each plume’s cross-section are calculated as a function of time. Aerosol- and contrail-particle core compositions are tracked for each size and affect optical properties in each plume. When line contrails sublimate/evaporate, their size- and composition-resolved aerosol cores and water vapor are added to the grid scale where they affect large-scale clouds. Algorithm properties are analyzed, and the end-result model is evaluated against in situ and satellite data.     

镧和铕与邻菲罗啉谷氨酸配合物的NMR和IR研究

合成了稀土镧和铕与谷氨酸，邻菲罗啉形成的二元及三元配合物，经元素分析确定该配合物的组成为Ｌｎ（ｐｈｅｎ）（Ｇｌｕ）３．７Ｈ２Ｏ（Ｌｎ＝Ｌａ，Ｅｕ）；Ｅｕ（Ｇｌｕ）３；１２Ｈ２Ｏ。用核磁共振和红外光谱研究与配体与稀土离子的配位方式，讨论了稀土离子的顺磁性及屏蔽效应对配合物的ＮＭＲ谱图的影响。     

基于多光谱图像分析的温室黄瓜叶片营养元素检测与诊断

采用CCD照相机加滤光片的方法,进行了基于多光谱图像分析的温室黄瓜叶片营养元素检测与诊断研究。对近红外光波段的叶片图像分别采用遗传算法和分水岭算法进行阈值选取,对两种算法二值化的效果进行对比分析,结果表明采用分水岭方法分割的图像,边界清晰,噪音小,与原图像更接近,背景和叶片分离的效果更好。NDVI与叶面积、叶片含氮量之间有明显的线性关系,R2分别为： 0.820 9和0.701 7。GNDVI与叶面积、叶片的含氮量之间也有较高的线性关系,R2分别为： 0.762 5和0.676 2。RVI与叶面积之间有明显的线性相关关系,R2为0.857 7,但与叶片的含氮量之间则包含了非线性成分,R2为0.598 8。以上结果表明,CCD照相机加滤光片可以作为一种作物含氮量信息的快速诊断方法。     

鸡冠花炒炭前后的XRD及FTIR光谱分析

比较鸡冠花炒炭前后XRD及IR光谱特征,探讨XRD及IR光谱对鸡冠花炒炭前后鉴别的意义。运用XRD光谱及IR二阶导数光谱,对不同产地鸡冠花炒炭前后进行光谱分析。鸡冠花及鸡冠花炭的XRD图比IR二阶导数谱差异更明显。XRD光谱技术可以对鸡冠花及鸡冠花炭进行直接、快速、有效的鉴别,可为鸡冠花及鸡冠花炭鉴别和质量控制提供可靠依据。     

发射光谱法测定乳浊料中的锆和铪

研究了用碳粉和二氧化钛作缓冲剂同时测定乳浊料中的锆和铪的发射光谱法,选择钛作内标线,不需分离、不需化学处理,直接压样于杯形的石墨电极中,具有简便、快速、准确的特点。对测定条件、干扰因素进行了研究,从而建立测定锆和铪的新方法。锆和铪的分析线分别为327.3和286.6 nm,内标线选择为钛的308.8 nm线,锆和铪的线性范围分别为0～0.50%和0～0.25%。锆和铪的检测限分别为0.001%和0.010%,其回收率为96.67%～105.0%,当n=9时,锆的RSD为3.61%;铪的RSD为4.82%;用于样品的测定取得了满意的结果。     

Some problems of analysis and optimization of plates and shells

The classical optimization problems of plates and shells to satisfy a priori given geometry and dynamical characteristics are considered. Orthotropic plates and shells with variable thickness and low transverse stiffness are analyzed. First, some useful theorems and their proofs are given. Then the finite approximation of the problem related to optimization of free vibrations of shells with transverse deformation and rotary inertia is discussed. The varational iteration (MVI) and Bubnov-Galerkin (MB) methods are applied, and their convergence and suitability for application to plates and shells analysis are discussed and numerically evaluated.     

FTIR直接鉴定紫苏子及其伪品的研究

本文首次采用傅里叶变换红外光谱法的单次反射采样技术,直接、快速、准确地测定了种子类中药材紫苏子及其伪品的红外光谱。结果表明:种子类中药材紫苏子及其伪品的种仁和皮层由于所含化学成分的不同,其红外光谱的吸收的位置和强度均有明显差异,发现紫苏子与白苏子为同种植物,野生紫苏子则有所区别,且紫苏子与其伪品石荠苧、苏州荠苧及疏花荠苧的红外光谱吸收差别较大。根据红外特征吸收能够达到中药材的真伪鉴别及种类认定的目的。该方法具有直接、快速、准确、无需制样等特点。     

A direct method for acoustic impedance measurement based on the measurement of electrical impedance of acoustic transmitter

A simple and straight forward method for acoustic impedance measurement is presented and evaluated. In this method a speaker is used as the signal source. The relationship between the electrical impedance of the speaker and its acoustical load is developed and studied. It is shown that the electrical current and voltage of the speaker relate to the acoustical pressure and volume velocity. The mechanical and acoustical impedances are therefore easily derived by measuring the electrical current and voltage of the circuit. The proposed method yield itself to the automatic computer measurement and can be used for the field and in situ measurements.Comparison of the measurement data with those from other methods proves the applicability and accuracy of the proposed method.     

New Homoclinic and Heteroclinic Solutions for Zakharov System

A new type of homoclinic and heteroclinic solutions, i.e. homoclinic and heteroclinic breather solutions, for Zakharov system are obtained using extended homoclinic test and two-soliton methods, respectively. Moreover, the homoclinic and heteroclinic structure with local oscillation and mechanical feature different from homoclinic and heterocliunic solutions are investigated. Result shows complexity of dynamics for complex nonlinear evolution system. Moreover, the similarities and differences between homoclinic (heteroclinic) breather and homoclinic (heteroclinic) tube are exhibited. These results show that the diversity of the structures of homoclinic and heteroclinic solutions.     

New Homoclinic and Heteroclinic Solutions for Zakharov System

A new type of homoclinic and heteroclinic solutions, i.e. homoclinic and heteroclinic breather solutions, for Zakharov system are obtained using extended homoclinic test and two-soliton methods, respectively. Moreover, the homoclinic and heteroclinic structure with local oscillation and mechanical feature different from homoclinic and heterocliunic solutions are investigated. Result shows complexity of dynamics for complex nonlinear evolution system. Moreover, the similarities and differences between homoclinic (heteroclinic) breather and homoclinic (heteroclinic) tube are exhibited. These results show that the diversity of the structures of homoclinic and heteroclinic solutions.     

ZnO and ZnS Nanostructures: Ultraviolet-Light Emitters,Lasers, and Sensors

ZnO and ZnS, well-known direct bandgap II–VI semiconductors, are promising materials for photonic, optical, and electronic devices. Nanostructured materials have lent a leading edge to the next generation technology due to their distinguished performance and efficiency for device fabrication. As two of the most suitable materials with size- and dimensionality-dependent functional properties, wide bandgap semiconducting ZnO and ZnS nanostructures have attracted particular attention in recent years. For example, both materials have been assembled into nanometer-scale visible-light-blind ultraviolet (UV) light sensors with high sensitivity and selectivity, in addition to other applications such as field emitters and lasers. Their high-performance characteristics are particularly due to the high surface-to-volume ratios (SVR) and rationally designed surfaces. This article provides a comprehensive review of the state-of-the-art research activities in ZnO and ZnS nanostructures, including their syntheses and potential applications, with an emphasis on one-dimensional (1D) ZnO and ZnS nanostructure-based UV light emissions, lasers, and sensors. We begin with a survey of nanostructures, fundamental properties of ZnO and ZnS, and UV radiation–based applications. This is followed by detailed discussions on the recent progress of their synthesis, UV light emissions, lasers, and sensors. Additionally, developments of ZnS/ZnO composite nanostructures, including core/shell and heterostructures, are discussed and their novel optical properties are reviewed. Finally, we conclude this review with the perspectives and outlook on the future developments in this area. This review explores the possible influences of research breakthroughs of ZnO and ZnS nanostructures on the current and future applications for UV light–based lasers and sensors.     

Mechanisms of corrosion in surface layers at solid-solution interfaces

This review is focussed on solids in the broad categories of oxides, both simple (e.g. binary) and complex (e.g. silicates, aluminosilicates, titanates), and sulfides as ceramics, minerals and surface coatings. Mechanisms of surface reaction, corrosion and leaching associated with protons, hydroxide, water and simple cations and anions are considered. A variety of mechanisms that have some generality in determining the kinetics and reaction products at the solid-solution interfaces is illustrated. The focus of the experimental studies is on the surface layers; their development, distribution of species, depth and control. Mechanisms discussed and illustrated include: diffusion; protonation and ion transfer to solution; lattice reaction; ion exchange (leaching); precipitation; surface oxidation; surface reconstruction; intergranular films and grain boundaries. Theoretical models for the first four mechanisms are presented.     

青海不同地区唐古特铁线莲中的微量元素分析

采用空气-乙炔火焰原子吸收光谱法对唐吉特铁线莲中的Ca、Zn、Mn、Cu、Fe、Mg、Co7种微量元素进行了含量测定.该方法的加标回收率在98.73％-102.27％之间,相对标准偏差在1.12％-2.10％之间,具有较高的准确度和精确度.唐古特铁线莲中微量元素的含量顺序为Mg＞Ca＞Fe＞Mn＞Zn＞Cu＞Co,且这7种元素与海拔没有线性关系.Mg、Ca、Fe、Mn和Zn含量较为丰富,其平均值分别为273.64、242.85、96.29、4.51、2.68mg/100g.这些研究结果为进一步探讨唐古特铁线莲的药理毒理和药效提供了科学依据.     

Penetration of waves into semi-infinite collisional plasmas

Penetration of longitudinal and transverse fields into a semi-infinite collisional plasma with fractionally accommodating boundary, having specular and diffuse reflecions is studied. The penetration of longitudinal field was studied by Landau and recently by Mason which was extended for transverse waves by Gupta and Varma. The theory is extended for collisions between electrons and ions according to B.G.K. Model, and its resemblence with metals for electrons and holes, gives its practical significance. The reflection coefficients and surface impedence are observed. The results are compared with non-collisional cases and it is observed that depth of penetration for collisional plasma decreases.     

Antennal morphology and sensillar ultrastructure of Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae)

The parasitoid beetle Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is an important parasite of longicorn beetles (Cerambycidae), and has been used in China for the biological control of the Asian longicorn beetle and the Japanese pine sawyer. In this study the antennal morphology and sensillar ultrastructure of D. helophoroides were observed using scanning electron microscopy and transmission electron microscopy. Two types of sensilla trichodea (Tr. 1 and Tr. 2), two types of sensilla basiconica (Ba. 1 and Ba. 2), three types of sensilla chaetica (Ch. 1, Ch. 2 and Ch. 3), and Bohm's bristles were identified according to the morphology and fine structure of each type of sensilla in both sexes. Ultrastructural studies revealed porous structures on the cuticle wall and dendritic branches in the inner lumen of Tr. 1, Tr. 2, Ba. 1, and Ba. 2, thereby suggesting chemoreceptor functions. No difference in shape, structure, sensilla distribution and typology was observed between the sexes. These structures likely have roles in the host locating and habitat searching behavior of adult D. helophoroides, and suggest future studies on the olfaction and host location behavior of D. helophoroides and other coleopteran parasitoids.     

An asymmetric single-channel color image encryption based on Hartley transform and gyrator transform

A novel asymmetric single-channel color image encryption using Hartley transform and gyrator transform is proposed. A color image is segregated into R, G, and B channels and then each channel is independently Hartley transformed. The three transformed channels are multiplied and then phase- and amplitude truncated to obtain first encrypted image and first decryption key. The encoded image is modulated with a conjugate of random phase mask. The modulated image is gyrator transformed and then phase- and amplitude truncated to get second encrypted image and second decryption key. The asymmetric (decryption) keys, random phase mask, and transformation angle of gyrator transform serve as main keys. The optoelectronic encryption and decryption systems are suggested. Numerical simulation results have been demonstrated to verify the performance and security of the proposed security system.