煤粉燃烧过程中相转变点的小波识别

相变点的识别对研究煤粉的低温共熔和结焦有重要意义.本文分别对活性炭和加入SiO2的活性炭混合物的DSC曲线求导得到的DDSC曲线进行小波分析,提取DDSC曲线的近似部分和细节部分,得到更多关于相变的定量信息,再结合其TG,DTG曲线进行分析,实现对以上两种样品燃烧过程中相变点的识别;并将该方法运用到煤粉燃烧过程的相变分析中,对相变点后的烧结形态的场发射扫描电镜分析结果表明该方法是可行的.     

Inactivation of bovine immunodeficiency virus by photodynamic therapy with HMME

To investigate the effect of photodynamic therapy (PDT) with hematoporphrin monomethyl ether (HMME) on bovine immunodeficiency virus (BIV) can provide the basis theory for photoinactivation of human immunodeficiency virus (HIV). To assess the protection of HMME-PDT on the cell line Cf2Th infected with BIVR29 by 3-(4,5)-dimethylthiahiazol-2-yl-3,5-di-phenytetrazolium bromide (MTT) with power density of 5 and 25 mW/cm2 and energy density from 0.6 to 3 J/cm<'2>. To observe the inhibition of membrane fusion using a new reporter cell line BIVE by fluorescence microscope. HMME-PDT has significant protectant effects on Cf2Th-BIVR29 with both power densities, especially in the group of high power density. Fluorescent microscope shows that there is no significant difference between the group of PDT and control, which means PDT could not inhibit the BIV-mediated membrane fusion.     

Quantitative correlation between (1)H MRS and dynamic contrast-enhanced MRI of human breast cancer

Proton magnetic resonance spectroscopy (¹H MRS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) provide functional information, including vascular volume, vascular permeability and choline (Cho) metabolism. In this study, we applied these two imaging modalities to quantitatively characterize 36 malignant breast lesions in 32 patients and analyzed the correlation between them. Cho concentration was quantified by single-voxel ¹H MRS using water as an internal reference. The measured Cho levels ranged from 0.32 to 10.47 mmol/kg, consistent with previously reported values. In 25 mass-type lesions, the Cho concentration was significantly correlated with tumor size (r=.69, P<.0002). In addition, the Cho level was found to be significantly higher in lesions presenting as mass-type lesions compared to non-mass-type diffuse enhancements (P=.035). The enhancement kinetics from tissues covered within each MRS voxel were measured and analyzed with a two-compartmental model to obtain pharmacokinetic parameters K^trans and k_ep. A significant correlation was found between the Cho level and the pharmacokinetic parameter k_ep (r=.62, P<.0001), indicating that tissues with a high Cho level have higher wash-out rates in DCE MRI. The results suggest a correlation between Cho metabolism and angiogenesis activity, which might be explained by the association of Cho with cell replication and angiogenesis required to support tumor growth.     

多模虚共轭相干态与多模真空态组成的叠加态光场的等阶N次方H压缩

构造了由多模虚共轭相干态|{iZ_j^*}〉_q与多模真空态|{0_j}〉_q两者的线性叠加所组成的两态叠加多模叠加态光场|{Ψ_q⁽²⁾}〉_q.利用多模压缩态理论,首次对该态的等阶N次方H压缩特性进行了详细研究.结果发现:态|{Ψ_q⁽²⁾}〉_q是一种典型的多模非经典光场,它可呈现出周期性变化的、任意阶的等阶N次方H压缩效应.     

A special form of electrodynamical response to a gravitational wave：outgoing and imploding photon fluxes

We have investigated the interaction of an electromagnetic (EM) wave with a standing gravitational wave (GW) in an external static magnetic field,and obtained concrete forms of first-order perturbative EM energy fluxes.Unlike the propagating properties of the “left-circular” and “right-circular” waves of the tangential perturbative energy fluxes around the symmetrical axis,the radial perturbative energy fluxes are expressed as the outgoing and imploding waves to the symmetrical axis.We also examine several physical examples and show that this effect can produce very small but nonvanishing radial perturbative photon fluxes.This may be useful for EM detection of the high-frequency relic GWs of the GHz region in quintessential inflationary models.     

Couplings between pion and charmed mesons

We compute the couplings , and using QCD sum rules. These couplings are important inputs in the meson-exchange model calculations used to estimate the amount of absorption due to pions and rho mesons in heavy-ion collisions. Our sum rules are constructed at the first order in the pion momentum , which give the couplings that are not trivially related to the soft-pion theorem. Our calculated couplings, which somewhat depend upon the values of the heavy meson decay constants, are , , and . Received: 10 October 2001 / Revised version: 25 October 2001 / Published online: 7 December 2001     

Development of an integrated optical system for warpage and hermeticity test of microdisplay

We have developed an integrated optical system to measure the warpage of a microdisplay product at post-packaging die-attach temperature and to test its hermeticity after manufacturing. This system is constructed based on the principle of Twyman/Green (T/G) interferometry and Newton interferometry. T/G interferometry is used to characterize warpage of the microdisplay's base-plate, while Newton interferometry is used to characterize the gap variance between face-plate and base-plate of the microdisplay. With these measurements, deformation and shape of the microdisplay can be comprehensively determined during its manufacturing process, which is critical for its quality test and reliability evaluation. Delicate mechanical system was designed to facilitate the optics integration and alignment. To evaluate the performance of the optical system itself, warpage of a sample was re-measured with Tailor–Hobson profilometer whose resolution is 10 nm, the results from these two testing systems agree well with each other. Some application examples of the integrated testing system were presented to verify its work efficiency.     

大型回热换热器的降温实验

大型低温配件的降温试验复杂和多变,文中针对大型回热换热器的降温进行了研究。将回热换热器置于特制的冷箱内,利用液氮作为冷源,氦气做为载冷剂为换热器提供降温条件;隔膜压缩机为循环氦气提供循环压力。试验前将换热器上面布置9支传感器,传感器所采集的数据自动记录并保存在上位机内,同时绘制降温曲线,为大型回热换热器的降温研究提供了数据。     

Guided surface modes in a hollow slab waveguide with a left-handed material substrate or cover

The structural dispersion characteristics of guided surface modes in a hollow slab waveguide with a left-handed material substrate or cover are investigated. Dispersion relation is derived by using normalized parameters, and universal dispersion curves have been obtained analytically, by solving transcendental dispersion equations in a reverse way. Existence condition, mode degeneracy and other dispersion properties of guided surface modes have been discussed for different ? or μ of three layers for this substrate or cover layer.     

Mechanistic study of the reaction of methyl peroxy radical (CH3O2) with formaldehyde (CH2O)

ABSTRACT

A direct dynamic study on the reactions of CH₃O₂?+?CH₂O was carried out over the temperature range of 300–1500?K. All stationary points were calculated with the M06-2X/6-311++G(d,p) level of theory and identified for local minimum. The energetic parameters were refined at QCISD (T)/cc-pVTZ and CCSD (T)/cc-pVTZ levels of theory. Three channels were explored and a reaction of hydrogen abstraction from CH₂O by CH₃O₂ was identified as dominant channel which involves the formation of a prereactive complex in the entrance channel. The rate coefficient of the dominant channel was calculated with TST and TST/Eck and the Eckart tunnelling effect is only important over the lower temperature region. The calculated rate coefficient of the dominant channel has positive temperature dependence and agrees reasonably with the available literature data.