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11.
Aydin Dogan Goktug Gunkaya Ender Suvaci Markus Niederberger 《Journal of Materials Science》2006,41(24):8196-8201
In this study, a non-aqueous method in a simple one pot reaction process was employed to synthesize nano-sized BaTiO3 particles and then electrophoretic deposition technique was employed for thin film coatings. In the first step of the preparation, metallic barium is directly dissolved in benzyl alcohol at slightly elevated temperatures. Then titanium isopropoxide was added following by a solvothermal treatment. At the end of the reaction, nearly spherical BaTiO3 nanoparticles were obtained typically 5 nm in diameter. After establishing the stability of the BaTiO3 suspension in ethanol, electrophoretic deposition process was performed without any additional operation. Alumina with platinum plating was used as substrate. To achieve the optimal process parameters, various voltages were applied by altering the cathode to anode distance as well as deposition time. High voltages application was possible without causing hydrolysis, because of the non-aqueous ethanol medium with higher surface charge of the nanoparticles. The deposited surface coatings were dried in air and sintered at various temperatures. SEM, EDX and XRD analysis were employed for the investigation of the coating. 相似文献
12.
Paul F. Mlakar Donald O. Dusenberry James R. Harris Gerald Haynes Long T. Phan Mete A. Sozen 《Canadian Metallurgical Quarterly》2005,19(3):197-205
On September 11, 2001, an airliner was intentionally crashed into the Pentagon. It struck at the first elevated slab on the west wall, and slid approximately 310?ft (94.5?m) diagonally into the building. The force of the collision demolished numerous columns and the fa?ade of the exterior wall, and induced damage to first-floor columns and the first elevated slab over an area approximately 90?ft (27.4?m) wide and 310?ft (94.5?m) long. None of the building collapsed immediately. The portion that remained standing, even after an intense fire, sustained substantial damage at the first-floor level. 相似文献
13.
Paul F. Mlakar Donald O. Dusenberry James R. Harris Gerald Haynes Long T. Phan Mete A. Sozen 《Canadian Metallurgical Quarterly》2005,19(3):206-211
On September 11, 2001, the reinforced concrete structure of the Pentagon Building was able to resist, without collapse, the impact of a large commercial airliner despite the total loss of 26 columns and severe damage to 15 columns at the ground level. The ensuing fire and related fire-fighting activities led to the collapse of a portion of the building approximately one-half hour after the impact. In this paper, the reasons for the demonstrated toughness of the reinforced concrete structure are examined and attributed to use of spiral columns, effective splicing of reinforcing bars, strong girders, and short span lengths. 相似文献
14.
The use of thermodynamic, statistical, and light and electron‐optical microscopic methods has made it possible to analyse the course of reactions during steel‐plant‐internal hot metal desulphurisation. The theoretical dependence between oxygen and sulphur activity has been used to develop an EMF‐measurement‐based technique for determining the sulphur content as the hot metal is desulphurised. The absence of magnesium sulphide from the collection of phases in the final slag because of the greater stability and secondary formation of calcium sulphide has been explained with the aid of thermo‐chemical calculations. 相似文献
15.
16.
In recent years, the interests of disassembly line have increased owing to economic reasons and the increase of environmental awareness. Effective line can provide many advantages in terms of economic aspect and it facilitates competition the companies with others. This study contributes to the relevant literature by a branch, bound and remember algorithm for disassembly line balancing problem with AND/OR precedence. The proposed exact solution method employs the memory-based dominance rule to eliminate the reduplicated sub-problems by storing all the searched sub-problems and to utilise cyclic best-first search strategy to obtain high-quality complete solutions fast. In this paper, minimising the number of stations is taken as the performance measure. The proposed methodology is tested on a set of 260 instances and compared with the mathematical model using CPLEX solver and five well-known metaheuristics. Computational results show that the proposed method is capable of obtaining the optimal solutions for all the tested instances with less than 0.1?seconds on average. Additionally, comparative study demonstrates that the proposed method is the state-of-the-art algorithm and outperforms the CPLEX solver and metaheuristics in terms of both solution quality and search speed aspects. 相似文献
17.
This study examined the effects of feeding pasture vs. concentrate on the distribution of CLA isomers in the lipids of longissimus and semitendinosus muscle, liver and heart muscle, and subcutaneous fat in beef bulls. Sixty-four German Holstein and German Simmental bulls
were randomly allocated to either an indoor concentrate system or periods of pasture feeding followed by a finishing period
on a concentrate containing linseed to enhance their beef content of n−3 PUFA and CLA. The concentrations of CLA isomers in
the different tissues were determined by GC and silver ion HPLC. The diet affected the distribution of individual CLA isomers
in the lipids of the different tissues. The concentration (mg/100 g fresh tissue) of the most prominent isomer, cis-9,trans-11 18∶2, was increased up to 1.5 times in liver and heart tissue of bulls fed on pasture as compared with concentrate. However,
no diet effect was observed for cis-9,trans-11 18∶2 in the lipids of longissimus muscle and subcutaneous fat. In all tissues, the second-most abundant CLA isomer in concentratefed bulls was trans-7,cis-9 18∶2. In contrast, trans-11,cis-13 18∶2 was the second-most abundant CLA isomer in all investigated tissue lipids of pasture-fed bulls. The concentration
of the trans-11,cis-13 18∶2 isomer was up to 15 times higher in tissues of pasture-fed bulls as compared with concentrate-fed animals. Furthermone,
diet affected the concentrations of the CLA trans,trans 18∶2 isomers. Pasture feeding significantly increased the concentrations of some trans,trans 18∶2 isomers as compared with concentrate, predominantly trans-12,trans-14 18∶2 and trans-11,trans-13 18∶2. Overall, pasture feeding resulted in significantly increased concentrations of the sum of CLA isomers in the lipids
of longissimus, muscle, subcutaneous fat, heart and liver muscle of German Holstein and German Simmental bulls, but not in semitendinosus muscle. 相似文献
18.
Phenylalanine Ammonia‐Lyase‐Catalyzed Deamination of an Acyclic Amino Acid: Enzyme Mechanistic Studies Aided by a Novel Microreactor Filled with Magnetic Nanoparticles
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Diána Weiser Dr. László Csaba Bencze Gergely Bánóczi Ferenc Ender Dr. Róbert Kiss Eszter Kókai Dr. András Szilágyi Prof. Dr. Beáta G. Vértessy Dr. Ödön Farkas Dr. Csaba Paizs Prof. Dr. László Poppe 《Chembiochem : a European journal of chemical biology》2015,16(16):2283-2288
Phenylalanine ammonia‐lyase (PAL), found in many organisms, catalyzes the deamination of l ‐phenylalanine (Phe) to (E)‐cinnamate by the aid of its MIO prosthetic group. By using PAL immobilized on magnetic nanoparticles and fixed in a microfluidic reactor with an in‐line UV detector, we demonstrated that PAL can catalyze ammonia elimination from the acyclic propargylglycine (PG) to yield (E)‐pent‐2‐ene‐4‐ynoate. This highlights new opportunities to extend MIO enzymes towards acyclic substrates. As PG is acyclic, its deamination cannot involve a Friedel–Crafts‐type attack at an aromatic ring. The reversibility of the PAL reaction, demonstrated by the ammonia addition to (E)‐pent‐2‐ene‐4‐ynoate yielding enantiopure l ‐PG, contradicts the proposed highly exothermic single‐step mechanism. Computations with the QM/MM models of the N‐MIO intermediates from l ‐PG and l ‐Phe in PAL show similar arrangements within the active site, thus supporting a mechanism via the N‐MIO intermediate. 相似文献
19.
M Mete Altnta Betül Krdar Z lsen
nsan Kutlu
Ülgen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(6):612-618
The recombinant Saccharomyces cerevisiae strain, YPB‐G, producing and secreting Bacillus subtilis α‐amylase and Aspergillus awamori glucoamylase as a fusion protein yielded efficient utilisation of starch. A segregated population balance model has been used to determine the probability of plasmid loss and plasmid copy number. The kinetics of cell growth and product (fusion protein) formation were based on a genetically structured model. The predictions were compared with the experimental observations obtained for the unstable recombinant S cerevisiae cells in a 1.5 dm?3 batch bioreactor with 30 g dm3 initial starch under non‐aerated conditions. The main advantage of the present model is that three different genetic classes were defined on the basis of the existence of plasmid and of the expression of the enzymes, ie cells containing plasmids and expressing the gene product, x1; cells containing plasmids and but not expressing the gene product, x2; and cells without plasmids, x3. It is confirmed by this model that the cells without plasmids outgrow and dominate in the fermentation medium (2.27 g dm?3 vs 0.51 g dm?3) as more and more glucose becomes available by the degradation of starch. © 2001 Society of Chemical Industry 相似文献
20.
This paper aims to develop methods that are capable of detecting manipulation in the Istanbul Stock Exchange. We take the difference between manipulated stock’s and index’s average daily return, average daily change in trading volume and average daily volatility and used these statistics as explanatory variables. The data in post-manipulation and pre-manipulation periods are used as non-manipulated instances while the data in the manipulation period are used as manipulated instances. Test performance of classification accuracy, sensitivity and specificity statistics for Artificial Neural Networks (ANN) and Support Vector Machine (SVM) are compared with the results of discriminant analysis and logistics regression (logit). We found that the data mining techniques (ANN and SVM) are better suited to detect stock-price manipulation than multivariate statistical techniques (discriminant analysis, logistics regression) as the performances of the data mining techniques in terms of total classification accuracy and sensitivity statistics are better than those of multivariate techniques. We also found that unit change in difference between average daily return of manipulated stock and the index has the largest effect while unit change in difference between average daily change in trading volume of manipulated stock and index has the least effect on multivariate classifiers’ decision functions. 相似文献