一种数字全息图零级项消除的新方法

针对离轴数字全息图中的零级项问题,提出用独立分量分析方法对零级项进行压缩.首先通过CCD获取同一物体的两幅干涉强度不同的全息图构成观测信号,然后采用独立分量分析方法(Independent Component Analysis(ICA))从观测信号中分离出零级项和共轭项,再从获得的共轭项中减去残余的零级项分量,实现零级项的有效压缩,并用模拟结果论证该方法在处理零级项压缩方面的优越性和有效性.     

纳米氧化锡锑改性水性聚氨酯的制备与表征

以异佛尔酮二异氰酸酯(IPDI)、聚醚二醇（N-210）、二羟甲基丙酸（DMPA）、一缩二乙二醇（DEG）、三羟甲基丙烷（TMP）及纳米氧化锡锑（ATO）浆料为主要原料,制备了稳定的纳米ATO改性水性聚氨酯(APU)乳液。 粒径测试及透射电子显微镜（TEM）观察显示,纳米ATO在水性聚氨酯中分散较好,乳液粒径均小于100 nm; FTIR分析表明,纳米ATO粒子与水性聚氨酯(WPU)间可能存在化学键; 热重分析(TGA)测试显示,随纳米ATO添加量的增加,胶膜最大热分解温度逐渐提高,最大提高了约20 ℃;紫外-可见-近红外吸收及保温性能测试表明,随着纳米ATO添加量的提高,胶膜在800~2500 nm的透过率逐渐降低,但涂层在可见光区透过率均超过70%,热阻率由1.34×10-2 m2·℃/W提高至3.17×10-2 m2·℃/W。     

采用低维特征映射的耳语音向正常音转换

在将耳语音转换为正常音时,为了研究降维后语音特征对耳语音转换的影响,分别对耳语音和正常音谱包络进行自适应编码以提取耳语音和正常音的低维特征,然后使用BP网络建立耳语音和正常音低维谱包络特征之间的映射关系以及正常音基频和耳语音低维谱包络特征之间的关系。转换时,根据耳语音低维谱包络特征获得对应正常音的低维谱包络特征和基频,对低维谱包络特征进行解码后获得对应的正常音谱包络。实验结果表明,采用此方法转换后的语音与正常音之间的倒谱距离相比高斯混合模型方法下降了10%,转换后语音的自然度和可懂度都有所提高。      

Thermal Quantum Discord in Pure Dzyaloshinskii-Moriya Model with Magnetic Field

We investigate the effects of the directions of Dzyaloshinskii-Moriya (DM) interaction vector and magnetic field on the quantum discord in the pure DM model. For different directions of DM vector, we find that there are different optimal parameter components of magnetic field. Moreover, we find that the optimal parameter components rules are the same for the Hamiltonian H₁ and H₂. According to the rules, for a certain axial DM vector, we can get the maximal quantum discord by adjusting the direction of the external magnetic field, which is feasible under the current experimental technology.     

Quantum Secure Communication by Using GHZ State in High-Dimensional Hilbert Space

We propose a quantum superdense coding secure communication scheme by using GHZ state. This scheme combines the ideas of quantum superdense coding and sequence transmission. Its distinct advantage is high source capacity. In addition, in checking eavesdropping, we need not to destroy quantum entanglement.     

Deterministic Secure Quantum Communication with Cluster State and Bell-Basis Measurements

We present a novel protocol for deterministic secure quantum communication by using the lour-qubit cluster state as quantum channel. It is shown that two legitimate users can directly transmit the secret messages based on Bellbasis measurements and classical communication. The present protocol makes use of the ideas of block transmission and decoy particle checking technique. It has a high capacity as each cluster state can carry two 5its of information, and has a high intrinsic efficieney 5ecause almost all the instances except the decoy checking particles （its numSer is negligible） are useful. Furthermore, this protocol is feasible with present-day technique.     

Quantum key distribution by comparing Bell states

We propose a quantum key distribution (QKD) scheme based on entanglement swapping. In this scheme, the methods to form secret keys are so interesting. By comparing initial Bell state and outcome of entanglement swapping, the secret keys between Alice and Bob are generated involuntarily.     

Multiparty quantum secret sharing of secure direct communication using single photons

We propose a protocol for multiparty quantum secret sharing of secure direct communication using single photons. In this protocol, random phase shift operations instead of some special discrete unitary operations used usually are employed to realize the sharing controls. The security of this protocol with respect to various kinds of attacks is discussed. Due to the complete randomicity of the phase shift characterizing the unitary operations, the security of secret sharing is therefore enhanced.     

皖南牌坊传统灰浆的科技研究

采用FTIR,XRD,SEM等技术,对皖南牌坊上的传统灰浆材料配方进行了初步研究。结果表明,牌坊灰浆样品为石灰掺桐油或糯米而形成的有机-无机复合材料。桐油灰浆强度的形成主要源于灰浆中石灰的碳化反应、桐油与氧气的交联反应和Ca2+与—COO-的配位反应以及由此而形成的致密片层状有机-无机复合结构。糯米淀粉对灰浆碳化过程的调控作用而形成的细密的微观结构是糯米灰浆具有良好性能的微观解释。     

Splitting Single-Photon Polarization State with Weak Cross—Kerr Nonlinearity

We propose a three-party scheme for quantum information splitting (QIS) of an arbitrary single-photon polarization state based on weak cross-Kerr nonlinearity combined with linear optics elements such as polarization beam splitters (PBSs) and half wave plates (HWPs). The scheme is generalized to the arbitrary-party case. With the help of quantum nondemolition (QND) measurements, our schemes can be accomplished in an almost deterministic way. The two schemes are feasible with the current technology.