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101.
Achieving IT‐based synergies through regulation‐oriented and consensus‐oriented IT governance capabilities
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Thomas Kude Miroslav Lazic Armin Heinzl Alexander Neff 《Information Systems Journal》2018,28(5):765-795
This study aims at exploring the IT governance capabilities that enable organizations to achieve IT‐based synergies. Following existing work on the contextualization of theories and drawing on the resource‐based view of the firm (RBV), we develop an RBV of IT‐based synergies in two steps. First, we adopt existing context‐specific constructs and relationships from prior work on IT governance capabilities, IT relatedness, and synergies to develop a preliminary contextualization of the RBV. Second, to further refine our theoretical framework, we conduct an exploratory field study that includes interviews with 26 CIOs and other IT executives from 21 multibusiness firms. Our findings suggest that IT governance capabilities lead to IT‐based synergies through IT relatedness and business process relatedness. We found regulation‐oriented IT governance capabilities (IT roles and IT processes) to increase IT relatedness, while consensus‐oriented IT governance capabilities (IT groups and relational capabilities) had a positive effect on business process relatedness. Our results suggest that, in isolation, IT and business process relatedness lead to IT cost synergies, while collectively enabling IT‐induced business synergies. Our study is among the first to treat IT relatedness as an endogenous construct and to explicitly integrate business process relatedness into the IT governance domain. Our context‐specific decomposition of IT governance capabilities helps to better explain their links to IT and business process relatedness. These findings contribute to a better understanding of the tension between IT‐based synergies and business‐IT alignment. Decision‐makers are guided in developing IT governance capabilities to achieve IT‐based synergies. 相似文献
102.
103.
Seyed Armin Zare Estekhraji Sahar Amiri 《Journal of Inorganic and Organometallic Polymers and Materials》2017,27(4):883-891
Anti-corrosion, anti-fungus, and self-cleaning properties of coatings containing ZnO–TiO2, SiO2–TiO2 and SiO2/TiO2/ZnO nanoparticles synthesized based on sol–gel precursors using tetra methoxysilane, 3-glycidoxypropyl trimethoxysilane, tetra (n-butyl orthotitanate) and zinc acetate dihydrate were investigated by FESEM, EDAX and TEM analyses. Results indicated uniform dispersion of inorganic nanoparticles in the range of 20–40 nm in size. Anti-corrosion property of the hybrid coating was characterized by EIS measurements and parametrically analyzed in an equivalent circuit when the coating was exposed to salt solution. Results showed that, ZnO and TiO2 nanoparticles enhance anti-corrosion property of the hybrid coatings. Anti-fungus and anti-bacterial properties of the coatings were determined by diameter of inhibition zone and inhabitation of bacterial growth, respectively. The coating containing ZnO and TiO2 nanoparticles showed anti-fungus and anti-bacterial properties which were related to their photocatalytic properties. Degradation of methylene blue in aqueous solution was determined by UV–Visible tests which indicated self-cleaning property of the coatings containing ZnO and TiO2 nanoparticles. 相似文献
104.
Yuexia Sun Lei Fang David P. Wyon Armin Wisthaler Love Lagercrantz Peter Strøm-Tejsen 《Building and Environment》2008
The experiment presented in this report was performed in a simulated aircraft cabin to evaluate the air cleaning effects of two air purification devices that used photocatalytic oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjective human assessments were used for the evaluation. Comparisons were made between conditions with and without the PCO units installed in the re-circulated air system. Four groups of 17 subjects were exposed for 7 h to each test condition. Chemical analysis indicates that ethanol, isoprene and toluene were decomposed by oxidation in the PCO units tested. However, some intermediate products, such as formaldehyde and acetaldehyde, were detected. Physiological measurements did not show any significant effects of the two PCO units except that skin dryness was reduced by operating PCO unit 2. Both positive and negative effects of using PCO units on subjective assessments were observed after the first 3 1/4 hours of exposure. After 6 h of exposure, a positive effect of using either PCO unit on symptoms of dizziness and claustrophobia was observed. 相似文献
105.
Grynbaum MD Kreidler D Rehbein J Purea A Schuler P Schaal W Czesla H Webb A Schurig V Albert K 《Analytical chemistry》2007,79(7):2708-2713
Whereas the hyphenation of gas chromatography (GC) with mass spectrometry is of great importance, little is known about the coupling to nuclear magnetic resonance spectroscopy (NMR). The investigation of this technique is an attractive proposition because of the valuable information given by NMR on molecular structure. The experiments shown here are to our knowledge the first hyphenating capillary GC to microcoil NMR. In contrast to liquids, gases have rarely been investigated by NMR, mainly due to the experimental difficulties in handling gases and the low signal-to-noise-ratio (SNR) of the NMR signal obtained at atmospheric pressure. With advances in NMR sensitivity (higher magnetic fields and solenoidal microprobes), this limitation can be largely overcome. In this paper, we describe the use of a custom-built solenoidal NMR microprobe with an active volume of 2 microL for the NMR detection of several compounds at 400 MHz, first in a mixture, and then with full coupling to capillary GC to identify them separately. The injected amounts of each analyte in the hyphenated experiments are in the range of 15-50 micromol, resulting in reasonable SNR for sample masses of 1-2 microg. 相似文献
106.
Schneider E Keller M Brennauer A Hoefelschweiger BK Gross D Wolfbeis OS Bernhardt G Buschauer A 《Chembiochem : a European journal of chemical biology》2007,8(16):1981-1988
Cyanine-5-labelled neuropeptide Y (NPY) was demonstrated to be an ideal universal fluorescent ligand for the combined investigation of NPY Y(1), Y(2) and Y(5) receptors. With respect to improved stability, detection of receptor subtypes in cells and tissues, and prevention of receptor internalization, small nonpeptidic fluorescent antagonists should be superior. Here we present a set of four fluorescent nonpeptide NPY Y(1) receptor (Y(1)R) antagonists. The highest affinity was obtained by labelling an N(G)-(6-aminohexanoyl)argininamide derived from the Y(1)R antagonist BIBP 3226, with Py-1, a small pyrylium dye. The fluorescent pyridinium-type Y(1)R antagonist, compound 4 had K(i) values of 29 nM and 2.7 nM, which were determined by radioligand binding and flow cytometry under equilibrium conditions, respectively; 4 had a K(b) value of 0.6 nM (Ca(2+) assay). The large Stoke's shift (541 vs. 615 nm) in buffer (PBS, pH 7.4) in the presence of 1% BSA and the red emission (quantum yield 56%) are advantageous with respect to the signal-to-noise ratio. The new probe was successfully used in fluorescence-based binding experiments evaluated by flow cytometry and confocal microscopy; this demonstrates the potential of pyrylium dyes for the preparation of fluorescent ligands that are applicable for the study of G protein-coupled receptors on living cells. 相似文献
107.
Weschler CJ Wisthaler A Cowlin S Tamás G Strøm-Tejsen P Hodgson AT Destaillats H Herrington J Zhang J Nazaroff WW 《Environmental science & technology》2007,41(17):6177-6184
We have used multiple analytical methods to characterize the gas-phase products formed when ozone was added to cabin air during simulated 4-hour flights that were conducted in a reconstructed section of a B-767 aircraft containing human occupants. Two separate groups of 16 females were each exposed to four conditions: low air exchange (4.4 (h-1)), <2 ppb ozone; low air exchange, 61-64 ppb ozone; high air exchange (8.8 h(-1)), <2 ppb ozone; and high air exchange, 73-77 ppb ozone. The addition of ozone to the cabin air increased the levels of identified byproducts from approximately 70 to 130 ppb at the lower air exchange rate and from approximately 30 to 70 ppb at the higher air exchange rate. Most of the increase was attributable to acetone, nonanal, decanal, 4-oxopentanal (4-OPA), 6-methyl-5-hepten-2-one (6-MHO), formic acid, and acetic acid, with 0.25-0.30 mol of quantified product volatilized per mol of ozone consumed. Several of these compounds reached levels above their reported odor thresholds. Most byproducts were derived from surface reactions with occupants and their clothing, consistent with the inference that occupants were responsible for the removal of >55% of the ozone in the cabin. The observations made in this study have implications for other indoor settings. Whenever human beings and ozone are simultaneously present, one anticipates production of acetone, nonanal, decanal, 6-MHO, geranyl acetone, and 4-OPA. 相似文献
108.
109.
VitaliI. Tararov Renat Kadyrov ThomasH. Riermeier Christine Fischer Armin Brner 《Advanced Synthesis \u0026amp; Catalysis》2004,346(5):561-565
The direct reductive amination of acetophenone with benzylamine or piperidine was studied in comparison with the hydrogenation of possible intermediates like a corresponding imine or enamine. No common features in terms of productivity and stereocontrol (in the case of chiral catalysts) have been found for both processes. Hence evaluation of efficient, selective and enantioselective catalysts for direct reductive amination appears to be a separate task. 相似文献
110.
Michael Limbach Suryakanta Dalai Armin deMeijere 《Advanced Synthesis \u0026amp; Catalysis》2004,346(7):760-766
A well reproducible and inexpensive preparation of the cyclopropylideneacetates 2 – 4 has been developed. The key intermediate 2‐(1′‐mesyloxycyclopropyl)acetic acid ( 8 ), produced either from methyl phenylacetate ( 1 ) or 3,3‐dimethoxypropionate ( 5 ‐Me) and 3,3‐diethoxypropionate ( 5 ‐Et) in a sequence of Kulinkovich reductive cyclopropanation, mesylation and oxidative cleavage or cleavage and oxidation, respectively, was either converted to the benzyl ester 11b , or chlorinated (brominated) via the in situ formed acid chloride. The α‐chloro‐ 12a and α‐bromo ester 12b were dehydromesylated by treatment with triethylamine to furnish methyl 2‐chloro‐2‐cyclopropylideneacetate ( 3 ‐Me) and the 2‐bromo analogue 4 ‐Me with an overall yield of 68% (65%, 68%) and 52% (49%, 51%) respectively, starting from 1 ( 5 ‐Me, 5 ‐Et). The parent benzyl cyclopropylideneacetate 2 ‐Bn was obtained by dehydromesylation of 11b with potassium t‐butoxide in t‐butyl methyl ether with an overall yield of 60% (57%, 9%) from 1 ( 5 ‐Me, 5 ‐Et). 相似文献