Quantification of several atmospheric gases from high resolution infrared solar spectra obtained at the south pole in 1980 and 1986

Simultaneous total column amounts of a number of minor and trace atmospheric gases above the South Pole in December 1980 and December 1986 have been deduced from analysis of high resolution solar absorption spectra recorded (by F. J. M. and F. H. M.) from Amundsen-Scott South Pole Station. These spectra also contain some limited information on the vertical profiles of the observed atmospheric gases.The data sets were recorded with a Bomem Michelson-type interferometer and analyzed with a spectral least-squares fitting procedure, utilizing the best available spectroscopic line parameters and absorption cross sections. Because the same instrument, line parameters, and analysis method have been used in analyzing the December 1980 and December 1986 data sets, the precision in comparing the column amounts from these two dates is rather high, about 10–20% for the stronger absorbing gases. For this reason, it has been possible to quantify or determine upper limits for differences between the December 1980 and December 1986 total column amounts, of a number of atmospheric gases including O₃, N₂O, HNO₃, CO₂, CH₄, and CF₂C_{1 2} (CFC 12). In addition, vertical column amounts for a number of atmospheric gases covered only in the December 1986 observations have been derived, including HC1, NO, NO₂, and C₂H₆. Some of these results will be discussed here. The HC1 measurements are especially interesting since the observed amounts are higher than expected from observations made at lower latitudes in the northern and southern hemispheres.     

烷类特种气体分析装置的研制及其应用

研制烷类特种气体分析专用的多维气相色谱仪，特制的热导检测器，具有手动－自动功能。设计了输气－配气装置和多维气相色谱流程。以微机控制，可按编辑程序清洗系统。检查本底，自动进样，显示或打印谱图和分析结果。可检测多种烷类特种气体组份及其中氧，氮，一氧化碳和甲烷等痕量杂质。     

Immobilized plant cells

Plant cells have been immobilized in alginate, where they have been shown to retain their biological activity. Such systems can be utilized for bioconversions.     

A stereotypic,transplantable liver tissue-culture system

A method of coculturing adult rat hepatic parenchymal cells (PC) and stromal cells in a three-dimensional framework of nylon filtration screens or biodegradable polymer meshes was developed in our laboratory. Rat liver stroma, which includes vascular and bile duct endothelial cells, fat-storing cells, fibroblasts, and Kupffer cells, were isolated by gradient centrifugation afterin situ liver perfusion and expanded in monolayer culture prior to seeding onto nylon screens or bioresorbable polyglycolic acid (PGA) polymers oriented into a felt-like construct. A second inoculum of freshly isolated PC was applied after the stromal cells became established. Histological analyses revealed that PC proliferation occurred until all available space for expansion within the template was exhausted. These cells retained their rounded morphology, and after 4–5 wk 7–9 “layers” of PC filled the 140-μm deep template. Dioxin-inducible cytochrome P450 activity was detected for up to 58 d in culture, and albumin, fibrinogen, transferrin, and soluble fibronectin were detected in the medium by enzyme-linked immunosorbent assay (ELISA) for 48 d in vitro. Immunohistochemical analysis of sections through the cultures confirmed the presence of these proteins as well as cytokeratin at the cellular level; the extracellular matrix stained for both collagen type III and laminin. Long-term PC proliferation and function were enhanced by the presence of stromal cells as well as by a meshwork template whose geometry allows the interaction of PC with stroma and matrix on several different planes. To permit transplantation, co-cultures of hepatic PC and stromal cells were established on PGA felt constructs instead of nylon screens. After 24 d in vitro, these constructs were grafted into sites in the mesentery, omentum, and sub-cutaneous tissues of adult Long-Evans rats. The growth of hepatocytes after 30 din situ was evident by histological analysis; grafts of co-cultures regenerated a liver-like architecture consisting of sinusoids and putative biliary structures. In addition, PC at these extrahepatic graft sites were positive for albumin, transferrin, and fibrinogen synthesis by immunohistochemistry. Graft survival was enhanced when recipients were subjected to 40% hepatectomy. Hepatic PC:stromal cell cocultures may prove useful in the restoration of liver function either by direct transplantation using PGA or similar templates, or as extracorporeal devices, using nylon screens.     

Syntheses of mixed ligands complexes of Ru(II) with 4,4′-dicarboxy-2,2′-bipyridine and substituted pteridinedione and the use of these complexes in electrochemical photovoltaic cells

The synthesis, spectral and photoelectrochemical studies of mixed ligand complexes of [Ru(dcbpy)₂(LL)]Cl₂, where LL=2,4-(1,3-N,N′-dimethyl)pteridinedione (DMP), 6,7-dimethyl-2,4-(1,3-N,N′-dimethyl)pteridinedione (MDMP), 6,7-diphenyl-2,4-(1,3-N,N′-dimethyl)pteridinedione (PhDMP), dibenzo[h,j]-(1,3-N,N′-dimethyl)isoalloxazine (BIAlo), 6,7-bis(pyrid-2-yl)-2,4-(1,3-N,N′-dimethyl) pteridinedione (PyDMP) were carried out. These complexes were attached to sol–gel processed TiO₂ electrodes and the photocells fabricated were illuminated with polychromatic radiation in the presence of I₂/I₃⁻ as redox electrolyte. The incident photon to current conversion efficiency determined was found to be 20–48%.     

Time-dependent fluctuations in infrared vsCH2 frequencies in acyl chain membranes of Acholeplasma laidlawii cells

We measured FT-IR spectra of intact Acholeplasma laidlawii cells grown at 37 °C on palmitic acid (C16:0) or on binary palmitic acid-d31/oleic acid (C16:0-d31/C18:1(9)) at an initial mole ratio of 2:3, which have been previously reported to produce significant fluctuations in CH₂ symmetric stretching (ν_sCH₂) and CD₂ asymmetric stretching (ν_aCD₂) frequencies (Biochim. Biophys. Acta 1279 (1996) 49). Time courses for acyl chain ν_sCH₂ and ν_aCD₂ frequencies determined from fourth derivative spectra are presented. Fluctuations were detected with the C16:0 enriched cells at temperatures above 40 °C as well as with the cells enriched in 2:3 C16:0-d₃₁/C18:1(9). These observations at temperatures above 40 °C for the C16:0 enriched cells were not in agreement with the conclusion in the previous work by Moore et al. Our results have suggested that the 2850 cm⁻¹ ν_sCH₂ band comprises two components arising from trans and gauche conformations, and that the fluctuations in ν_sCH₂ frequency are caused by random temporal changes in the relative intensities of these two components.     

染料敏化太阳能电池中大孔TiO2薄膜电极的制备及应用

采用溶胶-凝胶水热法制备了TiO₂纳晶薄膜电极，晶型为锐钛矿型。为了提高电极的光电性能，利用聚苯乙烯小球做造孔剂，制备了含有大孔隙的TiO₂纳晶薄膜电极，孔径约为200 nm，该电极具有较好的光漫反射性能，更重要的是球形大孔的存在，提高了凝胶电解质在TiO₂薄膜电极中的渗透和I₃^-离子的扩散性能，与不含大孔的TiO₂电极相比，电池的短路光电流提高约2 mA·cm^-2，光电转换效率提高0.6%。     

New Amphiphilic Polypyridyl Ruthenium（Ⅱ） Sensitizer and Its Application in Dye-Sensitized Solar Cells

Amphiphilic polypyridyl mthenium（Ⅱ） complex cis-di（isothiocyanato）（4,4＇-di-tert-butyl-2,2＇-bipyridyl）（4,4＇- dicarboxy-2,2＇-bipyridyl）ruthenium（Ⅱ）（K005） has been synthesized and characterized by cyclic voltammetry, ^1H NMR, UV-Vis, and FT-IR spectroscopies. The sensitizer sensitizes TiO2 over a notably broad spectral range due to its intense metal-to-ligand charge-transfer （MLCT） bands at 537 and 418 nm. The photophysical and photochemical studies of K005 were contrasted with those of cis-Ru（dcbpy）2（NCS）2, known as the N3 dye, and the amphiphilic ruthenium（Ⅱ） dye Z907. A reversible couple at E1/2=0.725 V vs. saturated calomel electrode （SCE） with a separation of 0.08 V between the anodic and cathodic peaks, was observed due to the Ru^Ⅱ/Ⅲ couple by cyclic voltammetry. Furthermore, this amphiphilic ruthenium complex was successfully used as sensitizers for dye-sensitized solar cells with the efficiency of 3.72% at the 100 mW·cm^-2 irradiance of air mass 1.5 simulated sunlight without optimization of TiO2 films and the electrolyte.     

Real-time measurement of nitric oxide using a bio-imaging and an electrochemical technique

Nitric oxide (NO) is an important mediator responsible for numerous physiological phenomena. Transient levels of NO in biological systems usually range from nanomolar to micromolar concentrations, with a rapid return to basal levels normally seen following these increases. Because NO can diffuse only over a local area in limited time due to such low levels of production and due to its short life-time prior to degradation, high spatial and temporal resolutions are required for direct and continuous NO measurement if the physiological role of NO is to be investigated in any system. For such purposes, analytical methods based on bio-imaging and electrochemical techniques for the measurement of NO are useful. In this paper, we describe the successful application of these methods to a number of biological systems. Specifically, complementary application of these methods demonstrate that it is possible to detect real-time NO production from nervous tissue with high spatial and temporal resolutions.