OPC(OLE for process control)作为一种工业标准,提供了硬件设备的统一“驱动”,极大的简化了软件与硬件之间的通讯编程。NI最新推出的LabVIEW8.0的DSC(dataloggingand supervisory control)模块进一步加强与简化了与OPCServer的通讯,...OPC(OLE for process control)作为一种工业标准,提供了硬件设备的统一“驱动”,极大的简化了软件与硬件之间的通讯编程。NI最新推出的LabVIEW8.0的DSC(dataloggingand supervisory control)模块进一步加强与简化了与OPCServer的通讯,而且其自身也可以作为一个OPC Server存在。介绍了如何通过LabVIEW 8.0 DSC模块与OPC Server进行通讯以及如何用它编写自己的OPC Server。展开更多
We theoretically analyze and experimentally demonstrate a method of generating equal-amplitude optical comb exploiting multi-frequency phase modulation. The theoretical analysis shows that 4n-1 equalamplitude spectral...We theoretically analyze and experimentally demonstrate a method of generating equal-amplitude optical comb exploiting multi-frequency phase modulation. The theoretical analysis shows that 4n-1 equalamplitude spectral lines can be obtained when the modulation signal comprises n frequency components including the fundamental frequency and the odd harmonic frequencies, and 2n＋1 equal-amplitude spectral lines can be obtained when the modulation signal comprises n frequency components including the fundamental frequency and the even harmonic frequencies. Then, we numerically simulate the spectra of 5, 7, 9, and 11 equal-amplitude spectral lines, respectively, which are also obtained in experiments with frequency separation of 30 MHz and flatness of better than 0.3 dB.展开更多
The glassy transition of the polyethylene terephthalate (PET) samples which have been subjected to solvent induced crystallization (SINC) was investigated by modulated differential scanning calorimetry (MDSC) and dens...The glassy transition of the polyethylene terephthalate (PET) samples which have been subjected to solvent induced crystallization (SINC) was investigated by modulated differential scanning calorimetry (MDSC) and density measurement. The differential of heat capacity signal, d C-p/dT from MDSC, was used to monitor the SINC process. It reveals that the T-g temperature shifts to higher value with the advancement of SINC. When the toluene-immersing time was longer (168 h), the detection of T-g become more difficult, because some smaller peaks emerged at the lower temperatures and these are explained as the movement of small segments in the amorphous region. These observed results are due to the morphology and structure introduced by the SINC process.展开更多
基金supported by the China Postdoctoral Science Foundation(No.20060400230)the Foundation for Innovation Talents by the Technology Ministry of Harbin(No.2006RFQXG025)
文摘We theoretically analyze and experimentally demonstrate a method of generating equal-amplitude optical comb exploiting multi-frequency phase modulation. The theoretical analysis shows that 4n-1 equalamplitude spectral lines can be obtained when the modulation signal comprises n frequency components including the fundamental frequency and the odd harmonic frequencies, and 2n＋1 equal-amplitude spectral lines can be obtained when the modulation signal comprises n frequency components including the fundamental frequency and the even harmonic frequencies. Then, we numerically simulate the spectra of 5, 7, 9, and 11 equal-amplitude spectral lines, respectively, which are also obtained in experiments with frequency separation of 30 MHz and flatness of better than 0.3 dB.
基金This work is supported by the National Key Projects for Foundamental Research,"Macromolecular Condensed State",of the State Science and Technology Commission of China.and National Natural Science Foundation of China
文摘The glassy transition of the polyethylene terephthalate (PET) samples which have been subjected to solvent induced crystallization (SINC) was investigated by modulated differential scanning calorimetry (MDSC) and density measurement. The differential of heat capacity signal, d C-p/dT from MDSC, was used to monitor the SINC process. It reveals that the T-g temperature shifts to higher value with the advancement of SINC. When the toluene-immersing time was longer (168 h), the detection of T-g become more difficult, because some smaller peaks emerged at the lower temperatures and these are explained as the movement of small segments in the amorphous region. These observed results are due to the morphology and structure introduced by the SINC process.
