2-甲基1，4-萘醌激发三重态与核酸反应的电子自旋共振自旋消减法研究

应用电子自旋共振（Electron spin resonance，ESR）自旋消减法，研究了内源性光敏剂2-甲基-1，4萘醌（VK3）的激发三重态（^3VK3^＊）与核酸及其组分的反应性顺序，得到。VK3^＊与四个核苷及四个单核苷酸的反应性顺序为Gua〉Ade〉Cyt〉Thy，dGMP〉dAMP〉dCMP〉TMP。结果与早前采用激光光解瞬态吸收光谱研究^3VK3^＊氧化DNA，测得的DNA及其组分阳离子自由基生成速率常数、核苷及核苷酸的氧化还原电位排序相一致。对^3VK3^＊与几种富含鸟嘌呤（G）的寡聚核苷酸：端粒DNA重复序列、端粒酶RNA亚基模版及其L6-P6发夹序列反应的ESR自旋消减法研究结果表明，其反应性大小与寡聚物中鸟嘌呤含量正相关，其中与端粒DNA的反应性最强。     

Elimination of dioxins in milk by dairy cows after the long-term intake of contaminated sugar beet pellets

ABSTRACT

Dried feed materials, such as sugar beet pellets, may be a source of high levels of PCDD/Fs. The studies followed up dioxin congener elimination from contaminated milk (5.02 ± 1.39 pg WHO PCDD/F-PCBs-TEQ g^?1 fat) up to 338 days after withdrawal of polluted feed ingredient (4.37 ± 0.25 ng PCDD/F/DL-PCBs-TEQ kg^?1 feed). The main objectives of the study were to estimate the length of the time needed to achieve an acceptable PCDD/F milk level as set by European Union law, to track the fate of the PCDD/F congeners, and to assess the potential risk for consumers associated with long-term consumption of contaminated milk. After approximately 200 days, the PCDD/F levels reached ML (2.5 pg WHO-TEQ g^?1 fat), then decreased to the action level after more than 300 days (1.75 pg WHO-TEQ g^?1 fat) for most of cows. The potential risk of PCDD/F/DL-PCBs intake was characterised by comparing the theoretically calculated weekly and monthly intakes with the toxicological reference values (TRVs). The dioxin intake for the average adult and high-milk consumers did not exceed half of any of the TRVs applied (TWI, PTMI). The consumption of milk by children in the amount recommended by nutritionists (500 ml day^–1) resulted in an exposure equal to 317% TWI and 275% PTMI.     

餐厨垃圾中温厌氧消化处理特性研究

中温厌氧消化处理餐厨垃圾能耗小、二次污染少,且能产出清洁能源,具有良好的环境效益和经济效益。叙述了进水COD浓度变化时垃圾中温厌氧消化处理的特性,指出,进水容积负荷变化时,反应系统中不出现酸化现象,随着进水有机浓度的提高,整体上COD去除率虽有所下降,但基本保持在95%以上;UASB反应器中产气量随进水有机浓度的增大呈增长趋势。     

卷取机前侧导板的间隙调整和结构改进

指出卷取机侧导板改造后出现的问题及影响,分析问题产生的原因,提出改进措施,详细介绍结构改进后具体安装调整方法,指出今后在使用调整中需要注意的问题。     

A comparison of the computatlonal complexities of the stride reduction methods

In this paper the 'Stride of 3' reduction method is compared with the wtfell known cyclic reduction method for solving tridiagonal systems derived from the discretiped steady state convection diffusion equation. The Stride of 3 algorithm is shown to be superior for moderate to large linear systems (e.g., of order > 20).     

Prediction of Particlulate Air Pollution using Neural Techniques

We have analysed the possibility of predicting hourly average concentrations of suspended atmospheric particulate matter with aerodynamic diameter less than 2.5 microns (PM2.5) several hours in advance using data obtained in downtown Santiago, Chile. By performing some standard tests used in the study of dynamical systems, we are able to extract some features of the time series of data. We use this information to estimate the amount of data on the past to be used as input to a neural network in order to predict future values of PM2.5 concentrations. We show that improvement of predictions is possible by using another neural network for noise reduction on the original series. The best results are obtained with a type of neural network which is equivalent to a linear regression. Up to six hours in advance, predictions generated in this way have significantly smaller errors than predictions based on the persistence of the long term average of the data.     

Adsorption properties of amphiphilic polyoxyalkylenated dimethylpolysiloxane derivatives on keratin

Adsorption properties of two types of dimethylpolysiloxane backbone derivatives, perfluoroalkyl polyoxyethylenated dimethylpolysiloxane (FPD) and polyoxyethylenated dimethylpolysiloxane (PD), onto keratin surfaces were investigated. Both polymers are amphiphilic, since they possess hydrophilic polyoxyethylene groups. FPD contains a perfluoroalkyl group that provides both water-and oil-repellent properties, whereas PD lacks these groups. Adsorption properties of these polymers onto keratin surfaces are considered a good index to evaluate these compounds as nonionics used in hair-coating agents, since keratin is a major component of hair. FPD was more likely to be adsorbed and less likely to be eliminated from the keratin surface than PD. Once FPD had been adsorbed onto the keratin surface, it was very slowly washed from the surface when it was immersed in stationary water, whereas PD polymers were quickly washed from the keratin surface. Even in running water, rapid elimination of FPD was not observed. The strong resistance to loss of FPD after washing with a large quantity of water may be due to the water-repellent nature of the perfluoroalkyl groups. As a comparison, FPD adsorption onto a glass surface was also investigated. The affinity to the glass surface was found to be less than to the keratin surface.     

中国科技馆新馆工程消声方案论证

本文对迷宫式结构消声的设计选用的实际效果进行了实地噪声参数测量，对中国科技馆新馆的四个影院的消声方案进行了论证，并给出了建议。     

车削过程振动的产生原因及消除措施

详细分析了车削加工中振动的主要类型及产生的原因,并从多个方面提出了减小或消除振动的措施。     

A simple background elimination method for Raman spectra

In this paper, we consider a new background elimination method for Raman spectra. The proposed method is based on peak detection, smoothing, and interpolation. Since the background is usually slowly varying with respect to wavelength, we could estimate the background by eliminating significant peaks. For this purpose, we seek the peaks by inspecting the smoothed derivative of a given spectrum. After clipping out the corresponding peak regions, we estimate the background by applying a modified linear interpolation. Then the background is eliminated from the measured Raman spectrum by simple subtraction. The experimental results showed that the proposed method gave satisfactory results for real Raman spectra as well as synthetic data. As the proposed method requires no prior knowledge of spectrum, we expect that the method could be applied to other spectral data as well.