新型炭复合材料吸附剂脱除汽油中硫化物的研究

制备了负载不同过渡金属离子（Ag^＋、Cu^2＋）的吸附剂Ag／Al2O3、Cu／Al2O3和Ag／SiO2，在固定床吸附脱硫装置上，考察了吸附剂对汽油模型化合物MGF-1（正庚烷中含噻吩硫760mg／L）的脱硫效果。结果表明，Ag／Al2O3具有较好的脱硫效果。将Al2O3在630℃下分别覆炭4，6，8h制得覆炭吸附剂，测定了覆炭吸附剂负载Ag^＋后对汽油模型化合物MGF-1和MGF-2的脱硫效果。结果表明，吸附剂覆炭后可明显提高吸附剂对硫化物的吸附选择性，当覆炭时间为6h时，吸附剂对硫化物的吸附选择性最好。     

快速一步法（ROSE法）提取DNA应用于RAPD—PCR扩增

对ＲＯＳＥ法的操作程序进行了进一步的简化，“一管一步”即可完成ＤＮＡ提取全过程，系统地与ＣＴＡＢ和ＳＤＳ法进行了比较，其提取过程明显比ＣＴＡＢ法、ＳＤＳ法简单，提取效率分别比ＣＴＡＢ、ＳＤＳ提高４倍和９倍，无污染物产生；与ＣＴＡＢ和ＳＤＳ法比分别节省费用约２００％和７００％。提取的ＤＮＡ能满足ＲＡＰＤ－ＰＣＲ研究的需要。因此，改良后的ＲＯＳＥ法可能是一种适合于ＤＮＡ提取自动化的方法，同时可能成为植     

Heterogeneity in intensive care units: fact or fiction?

Weight reduction, either by dietary or surgical means, is associated with prolongation of the heart rate corrected QT interval (QTc = QT/R-R0.5) and, on occasion, sudden death. Screening subjects with obesity before weight loss for prolonged QTc intervals is an accepted practice, although at present, there are no guidelines for whether subjects should be fasting before electrocardiogram (EKG) evaluation. The aim of this study was to test the hypothesis that EKG QTc interval duration is independent of meal ingestion. The hypothesis was tested in 11 healthy subjects who ingested a 500-kcal formula meal. A small decrease in absolute QT interval and a steady decline in R-R interval were observed for up to 60 minutes after formula ingestion. The QTc interval increased above baseline at 15 minutes (p < 0.007) after meal, a change that persisted for the 1-hour postmeal observation period. Spectral analysis of EKG R-R intervals (low-/high-frequency amplitude ratio) indicated a change in cardiac autonomic flow after meal ingestion. The QTc interval did not lengthen and R-R low-/high-frequency amplitude ratio remained unchanged in eight subjects evaluated in a similar manner but in whom isovolumic amounts of water replaced the meal. These observations suggest that (1) cardiac repolarization changes with fasting and feeding, (2) the QTc interval is influenced by meal intake, and (3) the autonomic nervous system may play a role in meal-related QTc changes. These findings have implications for the evaluation of patients with obesity before starting and during weight loss treatment.     

龚嘴大坝坝基渗出物成因分析研究

对龚嘴电站大坝坝基渗出物的特征、类型和成分以及渗出量的动态变化进行了研究，探讨了渗出物质的主要可能来源和成因机制。研究认为，渗出物的主要成分为铁、锰、钙的氧化物，由于其实际的元素渗出量不大，不会对大坝安全造成有意义的不利影响。     

Theory for microwave thermal emission from a layer of cloud or rain

Microwave thermal emission from a layer of cloud or rain consisting of spherical particles has been investigated. Scattering effects are studied in great detail with both numerical and analytical approaches. In the absence of ground emission, it is found that scattering induces brightening for optically thin layers and vice versa for optically thick layers. As a function of observation angle brightening occurs near nadir while darkening occurs at large angles in the case of small optical thickness. For large optical thickness, darkening occurs at all angles because of backscattering effects. When the layer of cloud or rain is above an air layer and an ocean surface at a higher temperature, it is found that the darkening effect at large optical thickness is much more pronounced. The darkening effect is also larger for vertical polarizations because the ocean emits more vertically polarized components. The effect of thermal emission and molecular absorption by atmospheric gases is also taken into account. Results obtained from analytical formulas under single scatteirng assumptions are compared and illustrated.     

Application of Strong Fluctuation Random Medium Theory to Scattering from Vegetation-Like Half Space

A model for vegetation scatter is developed using the theory of electromagnetic wave propagation in random medium with strong permittivity fluctuations. In applying the strong fluctuation theory, the singularity of the dyadic Green's function is taken into account. Backscattering coefficients are computed using the distorted Born approximation and illustrated as a function of incidence angle, frequency and moisture content of the vegetation. The mixing formula of the de Loor [28] was used in estimating the permittivity of leaves. The correlation function of Fung and Fung [18], and Fung and Ulaby [19] is used for the random medium.     

High-affinity capture of proteins by diamond nanoparticles for mass spectrometric analysis

Carboxylated/oxidized diamond nanoparticles (nominal size 100 nm) exhibit exceptionally high affinity for proteins through both hydrophilic and hydrophobic forces. The affinity is so high that proteins in dilute solution can be easily captured by diamonds, simply separated by centrifugation, and directly analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). No preseparation of the adsorbed molecules from diamonds is required for the mass spectrometric analysis. Compared to conventional MALDI-TOF-MS, an enhancement in detection sensitivity by more than 2 orders of magnitude is achieved for dilute solution containing cytochrome c, myoglobin, and albumin because of preconcentration of the probed molecules. The lowest concentration detectable is 100 pM for a 1-mL solution. Aside from the enhanced sensitivity, the overall performance of this technique does not show any sign of deterioration for highly contaminated protein solutions, and furthermore, no significant peak broadening and band shift were observed in the mass spectra. The promise of this new method for clinical proteomics research is demonstrated with an application to human blood serum.     

Plasma phospholipid metabolic profiling and biomarkers of type 2 diabetes mellitus based on high-performance liquid chromatography/electrospray mass spectrometry and multivariate statistical analysis

Liquid chromatography/mass spectrometry (LC/MS) followed by multivariate statistical analysis has been successfully applied to the plasma phospholipids metabolic profiling in type 2 diabetes mellitus (DM-2). Principal components analysis and partial least-squares discriminant analysis (PLS-DA) models were tested and compared in class separation between the DM2 and control. The application of an orthogonal signal correction filtered model highly improved the class distinction and predictive power of PLS-DA models. Additionally, unit variance scaling was also tested. With this methodology, it was possible not only to differentiate the DM2 from the control but also to discover and identify the potential biomarkers with LC/MS/MS. The proposed method shows that LC/MS combining with multivariate statistical analysis is a complement or an alternative to NMR for metabonomics applications.     

Fe2+/HClO氧化处理β-萘酚模拟废水的研究

以NaClO在酸性水溶液中生成的HClO代替Fenton试剂中的氧化剂H2O2,在Fe^2 的作用下对β—萘酚模拟废水进行处理,结果表明：使用HClO代替H2O2处理β—萘酚模拟废水能够取得更好的效果;废水pH、FeSO4和NaClO的投加量对降解效果有很大影响;光照可以促进β—萘酚的降解,60min后CODCr去除率可达60．8％,而同样条件下无光照时CODCr去除率仅为45．1％。     

Associations between diet and disease activity in ulcerative colitis patients using a novel method of data analysis

Background  

The relapsing nature and varying geographical prevalence of ulcerative colitis (UC) implicates environmental factors such as diet in its aetiology.