Adaptive neural nets for generation of artificial earthquakeprecursors

A novel methodology for generation of artificial earthquake precursors was tested on Southern California earthquake data in reverse and real time modes. When it was tried as a real time generator of earthquake precursors, it successfully predicted the June, 1992, Landers earthquake. The methodology is based on the use of adaptive neural nets (ANN) that process a set of time-dependent attributes calculated in a moving time-window. The most important of them is a danger function. The structure of the neural net is defined by the properties of input data in the moving time window. Thus, the neural net continuously adapts its structure to the time variant properties of the input attributes. The main problem the authors encountered in training the neural net on the earthquake data was the small size of the training set compared to the number of parameters that describe the structure of the ANN. To prevent instability and over-fitting in the training session, the authors used a technique similar to the damping method in least squares approximation     

Lipophilic lanthanide tris(beta-diketonate) complexes as an ionophore for Cl- anion-selective electrodes

A series of novel anion-selective electrodes were developed by incorporating lipophilic lanthanide tris(beta-diketonates) into plasticized poly(vinyl chloride) membranes. The new electrodes exhibited high selectivity toward Cl(-) anion in the concentration range of Cl(-) anion between 1.0 x 10(-5) and 1.0 x 10(-1) mol/L with near-Nernstian slopes and practically low detection limits. They offered non-Hofmeister anion selectivity, and interestingly discriminated Cl(-) anion from NO(3)(-), ClO(4)(-), and other anions. Since the employed lanthanide tris(beta-diketonates) were confirmed to form 1:1 highly coordinated complexes with Cl(-) anion, the observed high selectivity for Cl(-) anion was attributed to the characteristics of lanthanide coordination chemistry. All the prepared sensors worked well at neutral pH with quite short response time, <30 s, and could be used for longer than four months without any significant divergence in performance.     

Dynamic behaviors of lipid-like self-assembling peptide A6D and A6K nanotubes

Nanoscience and nanotechnology require development of nanomaterials that are amiable for molecular design from bottom up. Molecular designer self-assembling peptides are one of such nanomaterials that will become increasingly important for the endeavor. Peptides have not only been used in all aspects of biomedical and pharmaceutical research and medical products, but also have had enormous impact in nascent field of designed biological materials. We here report the dynamic structures of lipid-like designer peptide A6D (AAAAAAD) and A6K (AAAAAAK) that undergo self-assembly into nanotubes in water and salt solution. We not only analyzed their self-assemblies using dynamic light scattering to determine the critical aggregation concentration (CAC), but also use atomic force microscope to observe their nanostructures. We also propose a simple scheme by which these lipid-like peptides self-assemble into dynamic nanostructures. Since the knowledge of CAC is important for uses of these peptides for a variety of applications, these findings may have significant implications in the study of molecular self-assembly and for a wide range of utilities of designer self-assembling peptide materials.     

用碱回收炉提高发电量

20世纪碱回收炉的主要任务是回收有价值的割浆蒸煮药液，发电并不重要。现如今．用娥回收炉采增加发电量的重要性不断提高。这些变化的主要原因是电的价格。本文将介绍增加电产量的传统方法、新的思想和见解，特别是采用冷凝汽轮机其主要目的在于展示这些方法的效果．以便于其结果的可比性。本研究的基本事例为1台传统的碱回收炉，生产能力为4000t(固形物)／d，同时配备有备压汽轮机和冷凝汽轮机。本文将要介绍的方法为：增加黑液固含量、空气预热、吹灰系统、给水预热、蒸汽参数和电除尘后的热回收。     

GAS CHROMATOGRAPHY AND GAS CHROMATOGRAPHY-MASS SPECTROMETRY OF SOFT RESINS AND RELATED COMPOUNDS

The α-acids, β-acids, iso-α-acids, hulupones and humulinic acid have been separated by gas chromatography utilising the cool on-column injection technique on various bonded phase capillary columns. The α-acids were separated into cohumulone and humulone; the β-acids into colupulone and lupulone; and the hulupones into cohulupone and hulupone. Iso-α-acids were separated into four peaks; cis-isocohumulone, trans-isocohumulone, cis-isohumulone and trans-isohumulone. Flame ionization detection (FID) and chemical ionization mass spectrometry (CIMS) were used for chromatographic detection. Best results were achieved by employing a DB-1 fused silica capillary column with isooctane as the sample solvent .