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51.
We design control setting that allows the implementation of an approximation of an unitary operation of a quantum system under decoherence using various quantum system layouts and numerical algorithms. We focus our attention on the possibility of adding ancillary qubits which help to achieve a desired quantum map on the initial system. Furthermore, we use three methods of optimizing the control pulses: genetic optimization, approximate evolution method and approximate gradient method. To model the noise in the system we use the Lindblad equation. We obtain results showing that applying the control pulses to the ancilla allows one to successfully implement unitary operation on a target system in the presence of noise, which is not possible which control field applied to the system qubits. 相似文献
52.
I. Francis Cheng Yuqun Xie R. Allen Gonzales Przemys?aw R. Brejna Jency Pricilla Sundararajan B.A. Fouetio Kengne D. Eric Aston David N. McIlroy Jeremy D. Foutch Peter R. Griffiths 《Carbon》2011,(8):2852-2861
A new technique for the synthesis of large sheets (>10 cm2) of multi-layered graphene is presented. The condensation onto a heated surface (≈650 °C) of fumes from the thermal decomposition of asphalt in a ceramic crucible produces carbon films with a metallic sheen. Heating was done by a Fisher burner (natural gas/air) flame and the crucible was covered but exposed to laboratory atmosphere. These films were determined to be multi-layered graphene by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), Raman and infrared spectroscopy and X-ray diffraction. XPS indicates that the films are primarily sp2 hybridized carbon with small amounts of sp3 C–H and C–O or C–N functionalities. Based on the D band shift (1593 cm−1) and the ratio of D band to G band (1354 cm−1) of 0.93, the Raman spectrum also indicates that the material is sp2 C with some nanocrystalline features. The infrared spectrum exhibits A1U (868 cm−1) and E1U (1599 cm−1) stretching of the intralayer bonds of graphene. This form of chemical vapor deposition may be a scalable to give much larger surface areas. Furthermore, the process does not require metal substrates. Deposition onto silica nanosprings and diatomites is demonstrated. 相似文献
53.
Effect of extrusion conditions on iron stability and physical and textural properties of corn snacks enriched with soybean ferritin 下载免费PDF全文
Agnieszka Makowska Magdalena Zielińska‐Dawidziak Przemysław Niedzielski Michał Michalak 《International Journal of Food Science & Technology》2018,53(2):296-303
Soybean sprouts cultured in 20 mm FeSO4 were introduced into corn snacks (1.75–3.50%) to supplement iron. The effect of extrusion process on the ferritin iron stability and on product quality was studied. Iron stability in these fortified snacks depended mainly on feed moisture levels, with the best results seen when the feed moisture and temperature were 12% and 110 °C, respectively. Lower feed moisture was beneficial to hardness, expansion ratio and bulk density, while lower temperature increased snack hardness and density, while worsening the expansion ratio. The snacks’ water absorption was strongly and directly dependent on the temperature, while their solubility mainly depended inversely on feed moisture. All of the variables tested altered the colour of the snacks. The conditions that were best for producing the ferritin‐fortified snacks – 12% feed moisture, and temperature equal than or less to 140 °C – may yield a product with the desired quality features. 相似文献
54.
Rafa? Rakoczy Stanis?aw Masiuk Marian Kordas Przemys?aw Gr?dzik 《Chemical Engineering and Processing: Process Intensification》2011,50(9):959-969
The main objective of this paper is to present the measurement results of the pressure drop and the heat transfer coefficient in the various types of static mixers. The experimental investigations are provided for the explanation of the influence of hydrodynamic conditions on the heat transfer enhancement for different static mixers. Based on the analysis of the experimental database and theoretical considerations, original formulas are proposed for the determination of the power consumption and the heat transfer in various types of motionless mixing devices. In this paper a new criterion is also defined which takes into consideration both the heat transfer process and hydrodynamic conditions. This criterion may be successfully applied to the selection of a static mixer for the heat transfer problems. 相似文献
55.
N-nitrosodimethylamine (NDMA) formation during ozonation of dimethylamine-containing waters 总被引:2,自引:0,他引:2
Ozonation of aqueous solutions of dimethylamine (DMA) leads to the formation of nitrosodimethylamine (NDMA). The yield of reaction is low (below 0.4% in relation to DMA) and increases with increasing pH. Contact time, ozone/DMA ratio and radical scavengers are other variables controlling the yield of reaction. Data from the literature and observed ozonation by-products suggest that nitrosation of DMA might be responsible for nitrosamine generation. NDMA can be recognized as a by-product of ozonation of DMA in water, which is formed in a specific, but reasonable, range of ozone/DMA ratios. The reaction may have potential importance for water treatment technology assuming reasonable micrograms per liter of DMA concentrations in raw waters. 相似文献
56.
57.
P Drzewicz L Perez-Estrada A Alpatova JW Martin M Gamal El-Din 《Environmental science & technology》2012,46(16):8984-8991
Large volumes of oil sands process-affected water (OSPW) are produced during the extraction of bitumen from oil sands in Alberta, Canada. The degradation of a model naphthenic acid, cyclohexanoic acid (CHA), and real naphthenic acids (NAs) from OSPW were investigated in the presence of peroxydisulfate (S(2)O(8)(2-)) and zerovalent iron (ZVI). For the model compound CHA (50 mg/L), in the presence of ZVI and 500 mg/L S(2)O(8)(2-), the concentration decreased by 45% after 6 days of treatment at 20 °C, whereas at 40, 60, and 80 °C the concentration decreased by 20, 45 and 90%, respectively, after 2 h of treatment. The formation of chloro-CHA was observed during ZVI/S(2)O(8)(2-) treatment of CHA in the presence of chloride. For OSPW NAs, in the presence of ZVI alone, a 50% removal of NAs was observed after 6 days of exposure at 20 °C. The addition of 100 mg/L S(2)O(8)(2-) to the solution increased the removal of OSPW NAs from 50 to 90%. In absence of ZVI, a complete NAs removal from OSPW was observed in presence of 2000 mg/L S(2)O(8)(2-) at 80 °C. The addition of ZVI increased the efficiency of NAs oxidation by S(2)O(8)(2-) near room temperature. Thus, ZVI/S(2)O(8)(2-) process was found to be a viable option for accelerating the degradation of NAs present in OSPW. 相似文献
58.
Andrzej Głowacz Michał Grega Przemysław Gwiazda Lucjan Janowski Mikołaj Leszczuk Piotr Romaniak Simon Pietro Romano 《电信纪事》2010,65(1-2):3-17
This paper introduces a novel approach to a qualitative assessment of images affected by multi-modal distortions. The idea is to assess the image quality perceived by an end user in an automatic way in order to avoid the usual time-consuming, costly and non-repeatable method of collecting subjective scores during a psycho-physical experiment. This is achieved by computing quantitative image distortions and mapping results on qualitative scores. Useful mapping models have been proposed and constructed using the generalised linear model (GLZ), which is a generalisation of the least squares regression in statistics for ordinal data. Overall qualitative image distortion is computed based on partial quantitative distortions from component algorithms operating on specified image features. Seven such algorithms are applied to successfully analyse the seven image distortions in relation to the original image. A survey of over 12,000 subjective quality scores has been carried out in order to determine the influence of these features on the perceived image quality. The results of quantitative assessments are mapped on the surveyed scores to obtain an overall quality score of the image. The proposed models have been validated in order to prove that the above technique can be applied to automatic image quality assessment. 相似文献
59.
Wetting of Cu and Al by Sn-Zn and Zn-Al Eutectic Alloys 总被引:1,自引:0,他引:1
Janusz Pstruś Przemysław Fima Tomasz Gancarz 《Journal of Materials Engineering and Performance》2012,21(5):606-613
Wetting properties of Sn-Zn and Zn-Al alloys on Cu and Al substrates were studied. Spreading tests were carried out for 3 min,
in air and under protective atmosphere of nitrogen, with the use of fluxes. In the case of Zn-Al eutectic, spreading tests
were carried out at 460, 480, 500, and 520 °C, and in the case of Sn-Zn eutectic at 250, 300, 350, 400, 450, and 500 °C, respectively.
Solidified solder/substrate couples were cross-sectioned and subjected to microstructure examination. The spreading tests
indicated that the wetting properties of eutectic Sn-Zn alloys, on copper pads do not depend on temperature (up to 400 °C),
but in the lack of protective atmosphere, the solder does not wet the pads. Wettability studies of Zn-Al eutectic on aluminum
and copper substrates have shown a negative effect of the protective nitrogen atmosphere on the wetting properties, especially
for the copper pads. Furthermore, it was noted that with increasing temperature the solder wettability is improved. In addition,
densities of liquid solders were studied by means of dilatometric technique. 相似文献
60.
The surface tension and density of liquid Ag and Ag–Cu alloys were measured with the sessile drop method. The sessile drop
tests were carried out at temperatures from 1098K to 1573 K, on cooling (temperature decreasing stepwise) under a protective
atmosphere of high purity Ar (6N). The density of liquid Ag and Ag–Cu alloys decreases linearly with increasing temperature,
and an increase in concentration of copper results in a lower density. The surface tension dependence on temperature can be
described by linear equations, and the surface tension increases with increasing Cu content. The results of the measurements
show good agreement with existing literature data and with thermodynamic calculations made using the Butler equation. 相似文献