Decomposing regional productivity growth using an aggregate production frontier

The main contribution of this paper is the implementation of a new model which combines the two parametric approaches most commonly used in the productivity literature: fixed effects and stochastic frontiers. This allows us to discuss whether it is better to use average or frontier functions to estimate regional productivity. The empirical section uses panel data of Spanish regions over the period 1980–1995. Additionally, we calculate and decompose total factor productivity growth for the Spanish regions.     

水泥基渗透结晶型防水材料的工程应用和质量控制要点

以工程实例介绍水泥基渗透结晶型防水材料--XYPEX(赛柏斯)的性能特点、施工工艺,并通过分析该材料在施工中应把握的技术关键点,叙述须注意的质量控制要点.     

三沙港总体规划构想

三沙天然港湾优越,海上优势明显,但山多地少,陆域不足。因此,三沙港的规划应注重发挥海上资源优势,突破山海局限,移山填海拓展陆域,建城兴港,以港立城,建设海上三沙。     

硅橡胶防水涂料在防水工程应用的探讨

本文着重从施工的角度详细介绍了硅橡胶防水涂料的技术性能、防渗机理、各种不同工程部位的施工技术方案及操作要点和注意事项，对防水工程中推广应用硅橡胶防水涂料有很好的实践指导作用和参考价值。     

The creation of the incapable social tenant in Flanders,Belgium. An appraisal

As long as the social rented sector housed traditional families and the allocation procedures were rather loose, there was little commotion about the sector. A combination of a change in family structures, economic changes, and the strengthening of allocation procedures in favour of those most in need did change perceptions. Marginalisation and ghettoisation, especially of high-rise social housing estates, became buzzwords. This paper deals with the causes of these changes and with their implications. The marginalisation discourse calls for enlarging the target groups and estate-specific allocation procedures (to obtain a `social mix'). It illustrates a profound desire to diminish the number of ethnic minorities, single parents, single-person households and all kinds of people with a weak income profile who gain access to social rental housing. Furthermore, this discourse is reaching a crescendo: after it was started in the early 1990s by staff members of local social housing companies, it passed through the union of the social housing companies, the umbrella organisation of the sector, and parliament, reaching its greatest momentum so far in early 2002 when it was adopted by the Flemish housing minister. The counterpoint to this negative discourse is the high degree of satisfaction among social tenants, as observed in a study carried out in 1999. In our paper we will try to explain the background of these opposing trends and the possible consequences for the social rental housing in general and for tenants in particular.     

The potential use of <Emphasis Type="Italic">Fabaceae</Emphasis> lianas fibers in papermaking

The objective of this study was to anatomically characterize the fibers of nine species of Fabaceae lianas, to determine their potential in papermaking and to define which biometric parameters can be used to distinguish and identify individuals. The species presented average values of 76.81, 57.45, 42.55, and 1.81 for the felting index, wall fraction, coefficient of flexibility, and Runkel index, respectively. It is concluded that only M. ferox and M. madeirense can be recommended for papermaking.     

The impact of natural and artificial weathering on the visual,colour and structural changes of seven tropical woods

This study investigates the effects of wood weathering on changes in its macroscopic and colour characteristics in connection with changes in its molecular and anatomical structure. Seven hardwoods suitable for outdoor architecture—bangkirai, cumaru, cumaru rosa, ipé, jatobá, kusia, and massaranduba—were exposed to the exterior out of ground contact for 1–36 months according to EN 927-3, and for 1–12 weeks in Xenotest with water spraying according to partly modified EN 927-6. With prolonged weathering, the following changes occurred in the top surfaces of all tropical woods: (1) visual—creation of longitudinal macro-cracks, (2) spectrophotometry and CIE-L ^? a ^? b ^? —darkening in exterior exposure mainly due to pollutants, except for ipé, and vice versa lightening in Xenotest, as well as greening and blueing in both modes of exposure, (3) FTIR—faster decrease of guaiacyl than syringyl lignin, absolute decrease of conjugated and unconjugated carbonyl groups in the newly formed lignin-polysaccharide-extractive substrate in the photo-oxidized and washed-out cell walls, and decrease of cellulose crystallinity, (4) SEM—damaging of cell-walls by micro-cracks, and their degradation by thinning. Connections between changes of the individual characteristics of weathered woods, for example, between the colour (ΔE*, etc.) and the molecular structure (carbonyls, etc.), were also determined.     

Characteristics of cricket (<Emphasis Type="Italic">Gryllus bimaculatus</Emphasis>) chitosan and chitosan-based nanoparticles

The field cricket (Gryllus bimaculatus) is commonly consumed as food in different parts of the world. This study was performed to characterize the chitosan extracted from crickets and to assess its potential use to the growing functional market. The degree of deacetylation (DA), Fourier-transform infrared spectra, X-ray diffraction patterns, molecular mass, scanning electron microscopy spectra, and color were measured. Cricket chitosan nanoparticles were prepared, and the optimal conditions were identified. The molecular mass of the cricket chitosan was lower than that of commercial chitosan; however, the DA, FTIR, and XRD spectra were similar. The particle size (208.27 ± 3.47 nm), zeta potential (35.72 ± 1.29 mV), and polydispersity index (PDI: 0.27 ± 0.03) of the cricket chitosan NPs were superior to the commercial. Addition of NaCl reduced the cricket chitosan NPs size up to 15.5%. This finding is a novel trial to prove the availability of the insect chitosan with a low molecular mass as an active carrier source.