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1.
The objective of this study is to show that the core competence approach has validity when applied to construction. The focus is on the analysis of the fit between market strategies of firms in the building industry and their core capabilities. Certain strategies require specific core capabilities and key external and internal conditions supporting these capabilities. The resource-based approach focuses on the conditions in a firm, the internal capabilities, and supports a core capability that is demanded. The network literature will be related to external conditions that support a core capability of a firm active in a certain market. In a multiple case study, firms are analysed that are involved in different stages of the building process. The case studies demonstrate firms with consistent patterns of market strategies, core capabilities, and supporting internal and external conditions. The specific core capability of the firm under investigation determines the types of external and internal conditions that are critical.  相似文献   
2.
Sucrose phosphorylase is a promising biocatalyst for the glycosylation of a wide variety of acceptor molecules, but its low thermostability is a serious drawback for industrial applications. In this work, the stability of the enzyme from Bifidobacterium adolescentis has been significantly improved by a combination of smart and rational mutagenesis. The former consists of substituting the most flexible residues with amino acids that occur more frequently at the corresponding positions in related sequences, while the latter is based on a careful inspection of the enzyme's crystal structure to promote electrostatic interactions. In this way, a variant enzyme could be created that contains six mutations and whose half-life at the industrially relevant temperature of 60 °C has more than doubled compared with the wild-type enzyme. An increased stability in the presence of organic co-solvents could also be observed, although these effects were most noticeable at low temperatures.  相似文献   
3.
Adsorptive removal of antiscalants offers a promising way to improve current reverse osmosis (RO) concentrate treatment processes and enables the reuse of the antiscalant in the RO desalination process. This work investigates the adsorption and desorption of the phosphonate antiscalant nitrilotris(methylenephosphonic acid) (NTMP) from RO membrane concentrate onto granular ferric hydroxide (GFH), a material that consists predominantly of akaganéite. The kinetics of the adsorption of NTMP onto GFH was predicted fairly well with two models that consider either combined film-pore or combined film-surface diffusion as the main mechanism for mass transport. It is also demonstrated that NTMP is preferentially adsorbed over sulfate by GFH at pH 7.85. The presence of calcium causes a transformation in the equilibrium adsorption isotherm from a Langmuir type to a Freundlich type with much higher adsorption capacities. Furthermore, calcium also increases the rate of adsorption substantially. GFH is reusable after regeneration with sodium hydroxide solution, indicating that NTMP can be potentially recovered from the RO concentrate. This work shows that GFH is a promising adsorbent for the removal and recovery of NTMP antiscalant from RO membrane concentrates.  相似文献   
4.
Occurrence and formation of biologically active amines in foods   总被引:14,自引:0,他引:14  
Attention is given to the toxicology of biogenic amines and their occurrence and formation in foods, with special emphasis on fermented foods. The role of the associated flora, the starter cultures used and their interaction is discussed.  相似文献   
5.
The limitations of methods to determine the dimensional offsets in VLSI processes are discussed. The authors give a straightforward quantitative analysis of those methods in which the number of measurement points is not greater than the number of unknowns in the equations. General equations are derived for errors that are made in the extraction of dimensional offsets of conducting layers and MOS transistors. It is shown that, due to a dramatic amplification of small deviations, large errors occur if the extraction is not done carefully. The analysis is applied to the determination of the width offset of conducting layers and to the determination of the MOS transistor channel length offset  相似文献   
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We report on the SSTR2-binding properties of a series of four dimeric [Tyr3]octreotate analogues with different spacer lengths (nine, 19, 41, and 57 atoms) between the peptides. Two analogues (9 and 57 atoms) were selected as precursors for the design, synthesis, and biological evaluation of DOTA-conjugated dimeric [Tyr3]octreotate analogues for tumor targeting. These compounds were synthesized by using a two-stage click ligation procedure: a Cu(I) -catalyzed 1,3-dipolar cycloaddition ("copper-click" reaction) and a thio acid/sulfonyl azide amidation ("sulfo-click" reaction). The IC(50) values of these DOTA-conjugated [Tyr3]octreotate analogues were comparable, and internalization studies showed that the nine-atom (111) In-DOTA-labeled [Tyr3]octreotate dimer had rapid and high receptor binding. Biodistribution studies with BALB/c nude mice bearing subcutaneous AR42J tumors showed that the (111) In-labeled [Tyr3]octreotate dimer (nine atoms) had a high tumor uptake at 1 h p.i. (38.8 ± 8.3 % ID g(-1) ), and excellent tumor retention at 4 h p.i. (40.9 ± 2.5 % ID g(-1) ). However, the introduction of the extended hydrophilic 57 atoms spacer led to rapid clearance from the circulation; this limited tumor accumulation of the radiotracer (21.4 ± 4.9 % ID g(-1) at 1 h p.i.). These findings provide important insight on dimerization and spacer effects on the in vivo properties of DOTA-conjugated [Tyr3]octreotate dimers.  相似文献   
10.
Five xanthones from the bark of Garcinia cowa, namely 7-O-methylgarcinone E (1), cowanin (2), cowanol (3), cowaxanthone (4), and beta-mangostin (5), were found to possess in vitro antimalarial activity against Plasmodium falciparum with IC50 values ranging from 1.50 to 3.00 micrograms/ml. Complete 1H- and 13C-NMR assignments of these compounds are also reported.  相似文献   
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