川西须家河组前陆盆地构造层序及沉积充填响应特征

川西坳陷在须家河组沉积期为典型的周缘前陆盆地,受幕式造山运动的控制,其构造层序具有"二元体系域"的特征,即强烈造山期体系域和构造宁静期体系域。构造运动不仅控制着前陆盆地的层序地层发育,也会分配层序内部的沉积物充填。基于Vail经典层序地层学理论,综合利用地震、测录井等资料,分析研究区内构造层序类型及主控因素,阐明不同构造层序内部的沉积充填响应特征。结果表明:须家河组在前陆盆地期(须二段—须五段)可以划分为2个构造层序,其中须二段和须四段为强烈造山期体系域,须三段和须五段为构造宁静期体系域;构造运动是控制研究区构造层序发育的主要因素;强烈造山期体系域以粗粒沉积为主,发育冲积扇—辫状河三角洲—湖泊沉积体系,构造宁静期体系域以细粒沉积为主,发育曲流河三角洲—滨浅湖沉积体系。     

TD-PSOLA技术在汉语语音波形编码合成中的应用

以时域基音同步叠加（ＰＳＯＬＡ）技术和一个全汉语单音节库为合成单元进行汉语语音波形编码合成,针对汉语语音的音高、时长、音强以及音节之间的协同发音效应等影响合成语音质量的主要因素,建立相应音节的声调曲线、时长规则和音节之间协同发音规则等韵律规则,并利用时域基间同步叠加法原理调整合成语音的音高和时长,从而使合成的语音比较清晰自然。     

Modeling Pitch Contour of Chinese Mandarin Sentences with the PENTA Model

In continuous speech,the pitch contour of the same syllable may vary much due to its contextual information.The Parallel Encoding and Target Approximation (PENTA) model is applied here to Mandarin speech synthesis with a method to predict pitch contours for Chinese syllables with different contexts by combining the Classification And Regression Tree (CART) with the PENTA model to improve its prediction accuracy.CART was first used to cluster the syllables’ normalized pitch contours according to the syllables contextual information and the distances between pitch contours.The average pitch contour was used to train the PENTA model with the average contour for each cluster.The initial pitch is required with the PENTA model to predict a continuous pitch contour.A Pitch Discontinuity Model (PDM) was used to predict the initial pitches at positions with voiceless consonants and prosodic boundaries.Initial tests on a Chinese four-syllable word corpus containing 2048 words were extended to tests with a continuous speech corpus containing 5445 sentences.The results are satisfactory in terms of the Root Mean Square Error (RMSE) comparing the predicted pitch contour with the original contour.This method can model pitch contours for Mandarin sentences with any text for speech synthesis.     

连续语流中韵律层级和调型组合对重音感知的影响

由于汉语是声调语言,在连续语流中韵律词重音不仅会受到其所在韵律层级的影响,也会受到调型组合的影响。该文在大规模连续普通话语音数据库的基础上,从韵律层级和调型组合2方面对韵律词重音感知作了细致分析。实验结果表明,在不同韵律层级和调型组合条件下,重音感知呈现出规律性差异,主要表现为:1)随着韵律层级的上升,时长和基频都随着重音级别的增大而增大,但基频对重音感知的影响更大;2)在相斥的调型组合下,时长对重音感知的作用要显著高于其在相容调型组合下的作用;3)在连续语流中,双音节韵律词的重音模式没有显著稳定性。     

线性交换子的加权估计

 多线性交换子T_b(f)(x)=∫_Rⁿ∏_i=1^m(b_i(x)-b_i(y))k(x,y)f(y)dy在L^p(Rⁿ)(1K是一个标准的Calderón-Zygmund核.主要研究交换子Mf(x)=sup_x∈Q∫_Q|f(y)|dy,其中f∈L_loc(Rⁿ),x∈Rⁿ,Q是任何包含x的方体,并用Sharp极大估计得到了该多线性交换子在Herz空间的一个加权有界性.     

汉语连续语音三字词声调提取方法研究

连续的汉语三字词声调,由于受声道响应、音联、协同发音和变调规律等的影响,情况很复杂,故其基音提取远远较孤立字困难.文章简述了简化的自相关算法,分析了削波电平值对三字词基频检测的影响,得出了削波电平的取值范围,提出了对三字词基频检测应采取改变削波电平的观点,进而给出了三字词的基音提取方法.实验表明该方法简便、有效,提取成功率高.文章最后根据实验简述了三字词的变调规律和声调模式.     

汉语语音的基音快速提取算法

根据汉语语音信号的特点．该文提出一种简化的自相关基音提取的方法，算法具有简便、快速、准确和易于实现等特点。此方法不仅可用于孤立字．更适用于提取二字词的声词。实验表明，所得到的１５种二字词声调的基本模式和轻声变调等都与已有的研究报导相符。含有清声母音节时，二字词声调能提供音节分割和声韵分离的准确信号．基音提取成功率高于９０％。     

Effect of Ni addition on the glass-forming ability and soft-magnetic properties of FeNiBPNb metallic glasses

The effect of Ni addition on the glass-forming ability (GFA) and soft-magnetic properties of an (Fe1-xNix)75.5B14.5P7Nb3 (x=0-0.6) alloy system were investigated. We found that the addition of Ni was effective in allowing the alloy to approach a eutectic point as well as increasing the thermal stability of the supercooled liquid. By increasing the amount of Ni,the supercooled liquid region (ΔTx),the reduced glass transition temperature Trg (Tg/Tl) and the Y parameter [Tx/(Tg+Tl)] increased from 49 to 75 K,0...     

钝缀锦蛤选育群体F2生长性状相关性及遗传力分析

为开展钝缀锦蛤早期群体选育,通过生长性状研究群体选育的潜力,以经1代群体选育钝缀锦蛤(Tapes dorsatus)为亲本,通过阶段性移养的方式建立7个半同胞家系和混养F_2闭锁群体,分析12月龄和18月龄F_2群体的生长性状相关性,基于约束极大似然法(Restricted Maximum Likelihood,REML)估算12月龄钝缀锦蛤生长性状遗传力。结果显示钝缀锦蛤生长性状相关性达到极显著水平(P0.01)。根据多元回归分析结果,12月龄F_2群体壳长、壳高和壳宽对体质量直接作用为0.377,0.370,0.276;18月龄F_2群体壳长、壳高和壳宽对体质量直接作用为0.389,0.361,0.351。2个阶段壳体性状对体质量的直接作用相近,且直接作用大于间接作用,壳长对体质量直接作用最大。相比12月龄,8月龄F2群体壳宽对体质量的直接作用提高。12月龄和18月龄F2群体壳长(x_1)、壳高(x_2)、壳宽(x_3)对体质量(y)的回归方程分别为y=-48.724+0.513x_1+0.754x_2+0.882x_3(R~2=0.848)和y=-94.689+0.772x_1+1.141x_2+1.608x_3(R~2=0.864)。估算壳长、壳高、壳宽、体质量半同胞个体遗传力分别为0.14±0.16、0.10±0.08、0.49±0.28、0.29±0.14,壳宽的遗传力最高,表明壳宽是钝缀锦蛤选育的首选性状。本研究结果为钝缀锦蛤群体选育提供基础数据。     

二维1:-5 Lotka-Volterra复四次系统的可线性化条件

本文考虑了如下的一类平面四次复Lotka-Volterra系统的可线性化问题ẋ=x（1-a₃₀x³-a₂₁x²y-a₁₂xy²-a₀₃y³）,ẏ=-y（5-b₃₀x³-b₂₁x²y-b₁₂xy²-b₀₃y³）.该系统为四次齐次多项式扰动下的具有$1:-5$线性项的复Lotka-Volterra系统,给出了该系统可线性化的充分必要条件.     

汉语直接抱怨语的句调分析

基于实验语音学,选取情感类节目《金牌调解》为会话语料来源,使用Praat软件从句类的视角对63句语料进行句调分析,探究汉语直接抱怨语的句调特征及其句调走向与抱怨程度之间的潜在相关性。研究发现:汉语直接抱怨语具有句首高音高起始、句末伴随降调的韵律特征;以是非问句形式呈现的抱怨语句末句调发生变异,多伴随降调;抱怨程度对汉语直接抱怨语的句调走向无显著影响;以陈述句形式呈现的低于指责水平类抱怨语句末伴随降调,但降幅小于其他类别的抱怨语。     

稀土纳米粒子磁共振成像造影剂的研究进展

镧系元素(Ln)独特的磁学性质主要来源于其4f外层电子结构.利用Ln磁学性质合成的无机稀土纳米粒子被广泛用作磁共振成像(MRI)造影剂(CAs).总结了近年来磁性无机稀土纳米粒子在不同系列(T_1,T_2以及T_1-T_2) MRI CAs的应用现状及发展前景.     

二维Ti3C2Tx MXene材料的制备与工艺优化

二维（2D）过渡金属碳/氮化物（MXene）材料是当前最受关注的二维材料之一,其中二维碳化钛（Ti₃C₂T_x MXene）材料的研究最为广泛。该材料目前主要通过刻蚀三元碳化物或氮化物（MAX相）后进一步插层得到,因此MAX相材料的纯度和制备工艺条件直接决定了Ti₃C₂T_x MXene材料的物化性质。主要完成了不同Ti₃AlC₂ MAX相材料的筛选,选择氢氟酸（HF）刻蚀,并优化了不同的插层方法,制备了一系列Ti₃C₂T_x MXene材料。通过X射线衍射（XRD）、场发射扫描电镜（FESEM）、透射电子显微镜（TEM）、原子力显微镜（AFM）和X射线光电子能谱（XPS）等表征,确定使用原位锂离子（Li⁺）插层法可有效获得单层Ti₃C₂T_x MXene材料。制备的单层Ti₃C₂T_x MXene材料的表面平整,片径约为150 nm,厚度约为2 nm。同时,创新性地采用涡旋震荡辅助材料分层,极大地缩短了超声时间,提高了单层Ti₃C₂T_x MXene材料的产率（可达70%）,并且可以避免材料氧化,为Ti₃C₂T_x MXene材料未来应用提供了新方法。     

Structural, magnetic and transport properties of Sc-doped La0.7Sr0.3MnO3

The Sc-doped La_0.7Sr_0.3MnO₃ polycrystallines were prepared by thermal decomposition of complexes of metal ions with ethylenediamine-tetraacetic acid (EDTA). The dependence of structural, magnetic and transport properties on Sc doping was investigated. Moderate Sc doping level results in a sharp drop in Curie temperature, an increase in resistance and enhancement of magnetoresistance effect. At temperatures aboveT _MI,R(T) can be described asR(T) = R ₀exp(T ₀/T)^1/4, which indicates that conduction takes place by hopping between the localized states. The experimental data reveal that the change in magnetoresistance property is related to the structure.     

On the Family of Thue Equation ｜x^3 ＋ mx^2y-（ m ＋ 3）xy^2 ＋ y^3｜= k

The family of cubic Thue equation which depend on two parameters ｜ x^3 ＋ mx^2 y-（m＋3） xy^2＋y^3｜=k is studied. Using rational approximation, we give a smaller upper bound of the solution of the equation, that is quite better than the present result. Moreover, we study two inequalities ｜ x^3 ＋ mx^2y-（m ＋ 3） xy^2＋y^3 ｜ =k≤2m＋3 and ｜x^3 ＋mx^2y- （m＋3）xy^2 ＋ y^3｜ = k≤ （2m＋3）^2 separately. Our result of upper bound make it easy to solve those inequalities by simple method of continuous fraction expansion.     

Magnetoelectric and converse magnetoelectric res ponses in TbxDy1-xFe2-y alloy ＆ Pb（Mg1/3Nb2/3）（1-x）TixO3 crystal laminated composites

Measured results of magnetoelectric （ME） and converse magnetoelectric （CME） effects of TbxDy1-xFe2-y/ Pb（Mg1/3Nb2/3）（1-x）TixO3/TbxDy1-xFe2-y （TD/PMNT/TD） and PMNT/TD/PMNT laminated composites are presented. ME effect was determined by measuring laminate voltage output under a Helmholtz-generated AC field biased by a DC field （0-1 kOe） （1Oe = 79.58 A/m）. The CME effect was measured by recording the voltage induced in a solenoid encompassing the ME sample while exposed to a DC bias field and PMNT layer driven by a 10 V AC source. The ME and CME responses in the two laminated structure are linear. The highest values of ME coefficients in TD/PMNT/TD and PMNT/TD/PMNT composites are 384 mV/Oe and 158 mV/Oe, respectively, while the highest values of CME coefficients in the two composites are 118 mG/V and 162 mG/V （1 G=10^-4 T）, respectively.     

语音合成技术中的参数拟合与数据压缩

本文提出一种压缩语音参数、减少存贮数据率的新技术.其要点是采用四次代数曲线对经LPC分析技术所得的各参数序列进行拟合,将拟合参数加以贮存.在合成语音时,先由四次代数曲线参数算出语音LPC参数,然后合成语音.文中验证了此种方法的可行性.     

Three-Dimensional Stress and Stress Intensity for Tensioned Flat Plates with Edge Cracks

The stress in the thickness direction is an important factor influencing the fracture behavior of structural members. A stress σy tensioned flat plate with edge cracks is widely used as an analysis model. The stresses σx and σy for the plate model can be acquired from Neuber＇s solution. However, the solution is applicable only for a perfect plane stress or plane strain state. As a consequence of the thickness of the plate a three-dimensional （3-D） stress state will arise near the crack tip, resulting in a variation of the distribution of σx and σy stresses. A full analysis for the 3-D stress fields for a tensioned flat plate with edge cracks has been therefore carried out. The results show that the 3-D stress field near the crack tip is mainly determined by two factors： the thickness of the plate and the curvature radius at the crack tip. A further analysis has been carried out for the stress intensity near the crack tip. In this paper we give some equations matching to the 3-D stress and stress intensity, which describe precisely the stress state near the crack tip, and which can be applied effectively in engineering analysis.     

Plasma structures inside boundary layers of magnetic clouds

Magnetic cloud is an important interplanetary dis-turbance structure generated by the coronal mass ejections(CMEs), it has been widely investigated[1—5] since it wassuggested by Burlaga et al[1]. However, the boundary ofthe magnetic cloud has no objective definition yet. Manyobservational signatures have been used to identify thecloud boundary[6—13], as Burlaga[14] indicated, there is noconsistency among these various approaches. The problemof the BLs was not been solved because of its co…     

Formation and corrosion properties of Fe-based bulk metallic glasses

Bulk metallic glass (BMG) formation was explored in the Fe-B-Si-Nb alloy system though combined use of the atomic cluster line approach and the minor alloying strategy. The basic ternary compositions in the Fe-B-Si system were determined by the intersection points of two cluster lines, namely, Fe-B cluster to Si and Fe-Si cluster to B. 3at%–4at% Nb was added to the quaternary Fe-B-Si-Nb alloy. The casting experiments revealed that good glass-forming ability (GFA) occurred at the (Fe_73.4Si_8.2B_18.4)₉₆Nb₄ composition, and 3-mm diameter BMG samples were made. The glass transition temperature (T_g), crystallization temperature (T_x), and supercooled liquid region (ΔT_x=T_x-T_g) of this BMG were measured to be 866, 889, and 23 K, respectively. The BMG shows a high Vickers hardness of about Hv 1164, a Young’s modulus of 180 GPa, and a good corrosion resistance in the solutions of 1 mol/L HCl and 3wt% NaCl.