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81.
Underground space in land-use planning 总被引:3,自引:0,他引:3
Kimmo Rnk Jouko Ritola Kari Rauhala 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1998,13(1):39
In 1988, the Finnish Ministry of the Environment appointed a committee to review existing planning systems for underground construction. In its report in spring 1990, the committee concluded that current legislation and planning procedures were unsatisfactory. In response, a study on “Underground Space in the Planning and Land Use” was launched in June 1994, and was completed in summer 1996. The study formed part of Finland's Rock Engineering 2000 programme. The study reviewed the present situation in underground planning; examined current uses of underground facilities; created a basic method for the classifying the building potential of rock areas, identified the various methods currently available for assessing the environmental impacts of underground construction on the basis of the legislation in force (EIA); to developed methods for assessing the costs to the urban community of underground space, particularly in comparison with equivalent costs of space aboveground; and drafted a proposal concerning planning of different level and permit procedures for underground space. This paper discusses each aspect of the study. 相似文献
82.
Harri Pellikka Esa Tiiliharju Kari Halonen 《Analog Integrated Circuits and Signal Processing》2007,50(1):21-27
In this paper a 0.4 μm complementary SiGe process is used to fabricate up-conversion mixers for base-station applications.
A current feedback mixer, and a mixer with a folded input, were designed in order to test benefits obtainable from the use
of equally fast PNP- and NPN-transistors. The target was to improve linearity and to increase output compression point (
) of the mixers. A +5 dBm output compression point @2 GHz was measured while drawing 43 mA from 5 V voltage supply.
Harri Pellikka was born in Espoo, Finland, in 1980. He received the M.Sc. degree in electronics and electrical engineering from Helsinki
University of Technology in 2005. He has been with Helsinki University of Technology Electronic Circuit Design Laboratory
since 2003, where he works as research engineer. His research interests include the design of integrated circuits for telecommunication
applications.
Esa Tiiliharju was born in Rovaniemi, Finland, in 1966. He received the M.Sc. degree in information technology in 1995, and the Lic.Tech
degree in electrical engineering in 1998, both from Helsinki University of Technology, Finland. He has joined the Microelectronics
Laboratory in University of Turku in 2006. His research interests include the design of integrated circuits for telecommunication
applications.
Kari A. I. Halonen was born in Helsinki, Finland, on May 23, 1958. He received the M.Sc. degree in electrical engineering from Helsinki University
of Technology, Finland, in 1982, and the Ph.D. degree in electrical engineering from the Katholieke Universiteit Leuven, in
Heverlee, Belgium, in 1987.
Since 1988 he has been with the Electronic Circuit Design Laboratory, Helsinki University of Technology. From 1993 he has
been an associate professor, and since 1997 a full professor at the Faculty of Electrical Engineering and Telecommunications.
He became the Head of Electronic Circuit Design Laboratory year 1998. From 1997 to 1999 he was an associate editor of IEEE
Transactions on Circuits and Systems I. He has been a guest editor for IEEE Journal of Solid-State Circuits and the Technical
Program Committee Chairman for European Solid-State Circuits Conference year 2000. He has been awarded the Beatrice Winner
Award in ISSCC’02 Conference year 2002.
He specializes in CMOS and BiCMOS analog integrated circuits, particularly for telecommunication applications. He is author
or co-author over a hundred and fifty international and national conference and journal publications on analog integrated
circuits. He has several patents on analog integrated circuits. 相似文献
83.
Fenton's process was used in oxidative degradation of ethylediaminetetraacetic acid (EDTA) and novel complexing agents, namely BCA5 and BCA6, in distilled water and spiked samples of integrated pulp and paper mill waste water and ECF-pulp bleaching effluent. In waste water, over 90% of EDTA was degraded within 3 min when temperature was 60 degrees C, pH 4, and molecular ratio of H2O2:Fe2+:EDTA was 70:2:1 (0.26 mM EDTA) or higher. In spiked ECF bleaching effluent up to 42% of EDTA was degraded in similar reaction conditions, still higher than published results indicate biological waste water treatment of pulp and paper mill waste water being capable of. In pH 3, EDTA proved readily degradable by Fenton's process in otherwise similar conditions. According to these results, Fenton's process could be used as a pre-treatment method for EDTA-containing bleaching effluents prior to the biological waste water treatment. In addition, BCA5 and BCA6 proved their superiority in terms of degradability also by Fenton's process in both pH 3 and 4. 相似文献
84.
Susanne Siebentritt Philipp Walk Ulrich Fiedeler Iver Lauermann Kari Rahne Martha Ch. Lux‐Steiner Thomas P. Niesen Franz Karg 《Progress in Photovoltaics: Research and Applications》2004,12(5):333-338
ZnSe prepared by metal organic chemical vapor deposition is used as a buffer layer in Cu(In,Ga)(S,Se)2 solar cells without any utilization of wet chemistry. Cell efficiencies are as good as cells with the conventional CdS buffer. Stability of unencapsulated cells under damp heat conditions is somewhat lower for the alternative buffer. The first stages of photoassisted growth are studied. X‐ray photoemission spectroscopy shows that a continuous layer is formed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
85.
Isoamylase hydrolysates of wet‐ (WC) and dry‐cationised (DC) waxy maize starch were fractionated by ion‐exchange chromatography on CM‐Sepharose into an unbound and four bound fractions. The amount of bound dextrins was higher in the WC than in the DC sample. The fractions were characterised by gel‐permeation chromatography and proton‐NMR spectroscopy. The unbound fraction from the WC sample consisted mainly of linear chains formed from amylopectin. The dextrins in the bound fractions contained increased amounts, from 1.2—7.9, of cationic substituents per molecule and the degree of polymerisation increased with the density of substituents. Dextrins weakly bound to CM‐Sepharose had a linear structure, whereas more tightly bound fractions were mixtures of linear and branched dextrins. In the latter, the debranching was incomplete because of sterical hindrance by substituents at or close to the branch points. Most of the dextrins were partly hydrolysed by β‐amylase, but the more highly substituted fractions possessed also a population of β‐amylase resistant dextrins, suggesting substituents at the non‐reducing ends. 相似文献
86.
87.
Macroporous, monosized poly(meta‐divinylbenzene) and poly(para‐divinylbenzene) beads have been prepared by the two‐step activated swelling method with toluene or 2‐ethylhexanoic acid as pore‐forming agents. The type of divinylbenzene isomer as well as the type of porogen has a large effect on both physical and chemical properties of the monodisperse beads. Large pores are obtained with 2‐ethylhexanoic acid as porogen while beads prepared in the presence of toluene consist of only small pores and exhibit a shrinking behavior upon drying. The beads have considerable amounts of residual vinyl groups at the end of polymerization, as determined by bromination and Fourier transform IR analysis. The morphology and texture of the particles have been investigated by scanning electron microscopy and atomic force microscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 152–169, 2000 相似文献
88.
We have studied how different catalysts and diols affect the properties of low-molecular-weight (Mw (GPC) < 49800 g/mol) lactic-acid-based telechelic prepolymers. The catalysts and diols were tested separately in our previous studies. In this study, we used the best previously tested diols and catalysts together in order to prepare different types of telechelic prepolymers (for example, crystalline or amorphous). All condensation polymerizations were carried out in the melt, using different diols and different catalysts. The prepolymers were characterized by differential scanning calorimetry, gel permeation chromatography, titrimetric methods, and 13C nuclear magnetic resonance (13C-NMR). According to NMR, the resulting polymers contained less than 1 mol % of lactic acid monomer and less than 5.1 mol % of lactide. Dibutyltindilaurate, like tin(II)octoate, produced quite good molecular weights, but the resulting prepolymers contained exceptionally high amounts of D-lactic acid structures, and, therefore, these prepolymers were totally amorphous. Antimony(III)oxide produced a high-molecular-weight prepolymer when the diol used was aliphatic. Like DBTL, Sb2O3 produced amorphous prepolymers, which contained a lower amount of D-lactic acid structures than DBTL prepolymers. 1,8-dihydroxyanthraquinone produced a different kind of chain structure with Ti(IV)bu and Ti(IV)iso because one prepolymer had high crystallinity, and the other showed only a slight crystallinity. Sulphuric acid produced a very high-molecular-weight prepolymer with aliphatic 2-ethyl-1,3-hexanediol; and with aromatic diols, it produced quite good molecular weights, except with 1,8-dihydroxyanthraquinone. High-molecular-weight prepolymers produced with H2SO4 also showed high crystallinity; and, according to 13C-NMR, they did not contain lactide and D-lactic acid structures. © 1998 John Wiley & Sons, Inc. J Appl Polm Sci 67:1011–1016, 1998 相似文献
89.
Kari D Hecker Mary L Meier Rosemary K Newman C Walter Newman 《Journal of the science of food and agriculture》1998,77(2):179-183
Barley contains high levels of soluble dietary fibre, including mixed linked 1→3, 1→4β-D -glucans (β-glucan). An extract of β-glucan from waxy, hulless barley containing 56% total dietary fibre (TDF) was incorporated into flour tortillas, cornstarch pudding and apple granola bars to provide 2 g soluble fibre as β-glucan per serving. The foods were tested for objective functional properties. Flour tortillas with β-glucan were incorporated into rat diets and compared to diets containing an equivalent amount of cellulose, to test the fibre effect on growth and lipid metabolism parameters. Rats fed β-glucan tortillas had lower feed consumption and body weight (P<0·05) compared to those fed the cellulose tortillas, although feed/gain ratios were not different (P>0·05). Plasma LDL-cholesterol of rats fed β-glucan was lower (P<0·05) than cellulose-fed controls, although total cholesterol and triglycerides did not differ (P>0·05). Rats fed β-glucan tortillas had higher (P<0·05) faecal fat excretion, suggesting impairment of intestinal fat absorption. Liver composition data showed lower (P<0·05) levels of total lipid and cholesterol in β-glucan-fed rats. The results suggest that the barley β-glucan concentrate has potential as a food ingredient to provide supplemental soluble fibre which may be beneficial in reducing plasma LDL-cholesterol in humans. © 1998 SCI. 相似文献
90.