影响电能质量测量准确度的主要因素分析

文章首先介绍了电能质量监测的方式及监测内容,然后从电压、电流互感器,电阻、电容分压器,采样方式等三个方面探讨了其对电能质量测量准确度的影响。     

多巴胺功能化碳纳米管的制备及其性能

将浓硝酸氧化后得到的碳纳米管(MWNT-COOH)酰氯化,将活化后的MWNT-COCl与生物药物分子多巴胺(Dopa)继续发生反应,得到Dopa功能化的碳纳米管MWNT-Dopa.采用傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)对功能化的碳纳米管进行表征分析,进一步对MWNT-Dopa进行分散稳定性分析和生物矿化实验.结果表明,Dopa通过酰胺键共价接枝在MWNT上,且Dopa的功能化修饰有效提高了碳纳米管在水和乙醇中的分散稳定性及生物矿化活性.     

广播电台播控系统设计

南京广播电台播控系统设计包含两个方面：音频信号流程设计和播控机房环境设计。在音频信号流程设计中运用多元化、数字化、网络化的设计理念,将传统音频矩阵与现代网络矩阵巧妙的结合在一起。在播控机房环境设计中,着重人性化设计模式。组建一个集先进性,安全可靠性为一体的播控系统。     

Efficient loading of a single neutral atom into an optical microscopic tweezer

A single atom in a magneto–optical trap(MOT) with trap size(hundreds of micrometers) can be transferred into an optical microscopic tweezer with a probability of ～100%. The ability to transfer a single atom into two traps back and forth allows us to study the loading process. The loading probability is found to be insensitive to the geometric overlap of the MOT and the tweezer. It is therefore possible to perform simultaneously loading of a single atom into all sites of the tweezer array for many qubits. In particular, we present a simulation of the one-dimensional and two-dimensional arrays of an optical microscopic tweezer. We find the same qualitative behavior for all of the trap parameters.     

Rh/Al_2O_3-Cr_2O_3整体式催化剂的制备和二氯甲烷催化氧化性能

以粉末Al_2O_3为载体,通过浸渍Rh(NO_3)_3制备Rh/Al_2O_3催化剂;再以Rh/Al_2O_3、粉末Cr_2O_3和铝胶经过研磨混合制得催化剂活性浆料;将催化剂活性浆料涂覆到堇青石蜂窝陶瓷载体表面,经烘干,焙烧制得不同Rh含量的Rh/Al_2O_3-Cr_2O_3系列整体式催化剂.研究了该类催化剂的二氯甲烷催化氧化性能,发现Rh负载量为0.4 g/L的Rh/Al_2O_3-Cr_2O_3催化剂活性最佳,且未生成含氯中间产物.结合催化剂的表征结果发现,Rh的添加可增加催化剂的表面酸性和氧化还原性能,二者的协同作用提高了催化剂活性;而Cr_2O_3的存在有利于CH_3Cl中间体的进一步氧化,从而提高了催化剂的选择性.     

7-O-羧烷基化白杨素衍生物的合成及其抗癌活性

以白杨素(1)为起始原料,与溴代羧酸乙酯经取代反应制得中间体7-O-乙氧羰基烷基白杨素(3a~3d);3a~3d经水解反应合成了7-O-羧烷基化的白杨素衍生物(4a~4d),其中4b~4d为新化合物,其结构经1H NMR,13C NMR,IR和ESI-MS表征。初步的体外抗癌活性实验结果表明,3和4对人肝癌细胞Hep G2和人胃癌细胞MGC-803具有一定的抗癌活性,且大多数化合物的抗癌活性比母体化合物1强,其中6-(5-羟基-2-苯基-4H-苯并吡喃酮-7-氧)己酸(4d,IC504.04μmol·L-1)对MGC-803细胞的活性抑制作用强于阳性药物DDP(IC504.40μmol·L-1)。     

非负张量Z谱的Brauer型上界

In this paper, we have proposed an upper bound for the largest Z-eigenvalue of an irreducible weakly symmetric and nonnegative tensor, which is called the Brauer upper bound:■where■ As applications, a bound on the Z-spectral radius of uniform hypergraphs is presented.     

Growth,characterization, and Raman spectra of the 1T phases of TiTe2, TiSe2, and TiS2

High-quality large 1$T$ phase of Ti$X_2$ ($X ={\rm Te}$, Se, and S) single crystals have been grown by chemical vapor transport using iodine as a transport agent. The samples are characterized by compositional and structural analyses, and their properties are investigated by Raman spectroscopy. Several phonon modes have been observed, including the widely reported $A_{1g}$ and $E_g$ modes, the rarely reported $E_u$ mode ($\sim$183 cm$^{-1}$ for TiTe$_2$, and $\sim$185 cm$^{-1}$ for TiS$_2$), and even the unexpected $K$ mode ($\sim$85 cm$^{-1}$) of TiTe$_2$. Most phonons harden with the decrease of temperature, except that the $K$ mode of TiTe$_2$ and the $E_u$ and "$A_{2u}$/Sh" modes of TiS$_2$ soften with the decrease of temperature. In addition, we also found phonon changes in TiSe$_2$ that may be related to charge density wave phase transition. Our results on Ti$X_2$ phonons will help to understand their charge density wave and superconductivity.     

基于TMS320F2812存储测试系统设计

对于武器动态参数的测试研究,设计了基于TMS320F2812DSP的数据采集和数据处理系统。在深刻理解信号特征的基础上,并结合当今日益发展的数据压缩技术,设计、改进得到一种可应用于实际情况、能够满足节省存储空间和提高数据传输速度的需求的LZW和游程组合压缩算法。这样有利于复杂环境下动态参数的记录、地面采集、传输和数据处理成本费用,可通过同样的信道,测量更多参数。此外,本文对数据压缩效果进行了测试,实验证明采用该算法能实时、高效地对AD采集到的数据进行压缩处理。     

An efficient algorithm for optimal allocation of wavelength converters in wavelength routing optical network

In a wavelength routing optical network(WRON),the optimal allocation of wavelength converters(WCs)is very important to minimize the number of WCs,enhance the fiber utilization,reduce the blocking probability,etc..In this paper,a novel simplified network model with shared WCs has been proposed.An effective algorithm for optimal allocation of shared WCs has been presented by using a revised Dijkstra algorithm and genetic algorithm(GA).The effectiveness of the revised algorithm was verified through the simulation on Nature and Science Foundation(NSF)net of USA.This revised algorithm can achieve blocking probability 36% less than the algorithm in previous work,and the calculating time of the minimum blocking probability can be reduced dramatically.