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101.
Bui Minh Phong 《Acta Mathematica Hungarica》2006,113(1-2):63-71
Summary We prove that if a complex valued completely multiplicative function F and a positive integer ℓ≦5 satisfy the condition F(N) = Uℓ, where Uℓ is the set of all ℓ-th roots of unity, then {F(n+1) F(n) ∣ nε N} = Uℓ. 相似文献
102.
103.
Let D be a division ring with center F and K a division subring of D. In this paper, we show that a non-central normal subgroup N of the multiplicative group
$$D^*$$
is left algebraic over K if and only if so is D provided F is uncountable and contained in K. Also, if K is a field and the n-th derived subgroup
$$D^{(n)}$$
of
$$D^{*}$$
is left algebraic of bounded degree d over K, then
$$\dim _FD\le d^2$$
. 相似文献
104.
The possibility of taking into account concentration effects in the determination of optical constants of latex in the visible and near IR regions of the spectrum is demonstrated, and the limits of applicability of the methods proposed for this purpose are determined. The limiting concentration of particles in suspensions for which these effects should be taken into account depend on the particle size. Using latex as an example, ways of increasing the accuracy of reconstruction of optical constants of weakly absorbing particles of micron and submicron size are shown. Similar concentration effects can take place in the study of blood substituents, proteins, and other weakly absorbing particles in weakly absorbing media. 相似文献
105.
Cam Van T. Do Mai Huong T. Pham Thanh Yen T. Pham Cuc T. Dinh Thu Uyen T. Bui Thuan Dang Tran Van Tuyen Nguyen 《Current Opinion in Green and Sustainable Chemistry》2022
Domestic wastewaters are produced in huge volumes and abundant with carbon, nitrogen and phosphorous, which are a promising source of nutrients for production of microalgae. Microalgae-based bioremediation of domestic wastewater offers various advantages over traditional treatment approaches because the process consumes CO2, completely removes nitrogen and phosphorous for production of green biomass and oxygen. Moreover, the abundance of biochemical compositions (e.g., lipids, proteins, carbohydrates, bioactive compounds) of microalgae biomass is superior to terrestrial plant biomass in refining to multi-products having variety of commercial values. In this review, the most dominant microalgae used for simultaneous removal of pollutants and production of biomass and metabolites from domestic wastewater are presented. Biorefinery of microalgae biomass produced from domestic wastewater for production of multiple products is also explored. Finally, challenges and perspectives of successful microalgae-based bioremediation of domestic wastewater toward the biorefinery are briefly discussed. 相似文献
106.
107.
Minh-Phuong Ngoc Bui Xuan-Hung Pham Kwi Nam Han Cheng Ai Li Eun Kyu Lee Ho Jung Chang Gi Hun Seong 《Electrochemistry communications》2010,12(2):250-253
The arrays of gold nanoparticles (AuNPs) were fabricated on flexible and transparent single-walled carbon nanotube (SWCNT) films using the electrochemical deposition method, and the patterned nanotubes were then used as electrodes for hydroxylamine detection. The sizes and densities of the AuNPs could easily be controlled by varying the amount of charge deposited, and the gold-deposited area showed a homogeneous distribution on the exposed SWCNT film surface. X-ray diffraction analysis of the AuNPs shows a face-centered cubic structure that is dominated by the lowest energy {111} facets. The oxidation of the hydroxylamine on the AuNP-deposited SWCNT films depended strongly on the solution pH, and the maximum catalytic current was observed at a pH of 9.0. A linear electrical response was observed for concentrations ranging from 0.016 to 0.210 mM, and the detection limit and the sensitivity were 0.72 μM and 165.90 μAmM?1 cm?2, respectively. Moreover, the amperometric response in hydroxylamine showed a stable response for a long time (300 s), during which time it retained 94% of its initial value. In the long-term storage stability test, the current response to hydroxylamine decreased slightly, with only 17% leakage after 30 days. 相似文献
108.
An enantioselective α-amination of aryl oxindoles catalyzed by a dimeric quinidine has been developed. The reaction is general, broad in substrate scope, and affords the desired products in good yields with good to excellent enantioselectivities. This study provides the first examples of a general organocatalytic method for the creation of nitrogen-containing, tetrasubstituted chiral centers at C(3) of various aryl oxindoles. Furthermore, new catalysts and insights into structural elements of the catalysts that significantly influence enantioselectivities are disclosed. 相似文献
109.
Si Bui Quang Tran Doyoung Byun Vu Dat Nguyen Hadi Teguh Yudistira Myoung Jong Yu Kyun Ho Lee Jaeuk U. Kim 《Journal of Electrostatics》2010,68(2):138-144
In this paper, “end effect”, which represents the deflection of meniscus of boundary nozzles in an array due to asymmetric electric field and repulsive forces between adjacent nozzles, is experimentally investigated and a polymer-based electrospray device is fabricated and tested to minimize the end effect. For the electrically conductive nozzles of electrospray, the end effect could be reduced by dummy nozzles, through which no liquid is supplied, mounted at the boundary of the array. However, the polymer-based electrospray device can eliminate the end effect without using the dummy dry nozzles due to dielectric characteristic. A novel multiple nozzles of Polymethyl Methacrylate (PMMA)-based electrospray device was successfully fabricated and evaluated for reducing the end effect, showing no deflection of menisci through the boundary nozzles. And ten nozzles device was fabricated and observed to eject liquid jet simultaneously. The electrical current of the spray issued from the nozzles of the polymer-based electrospray device is measured with respect to flow rate and shows a good agreement with the scaling law. 相似文献
110.
Kerstin Strupat Viatcheslav Kovtoun Huy Bui Rosa Viner George Stafford Stevan Horning 《Journal of the American Society for Mass Spectrometry》2009,20(8):1451-1463
A MALDI source is interfaced to a modified LTQ Orbitrap XL instrument. This work gives insight into the MALDI source design
and shows results obtained with the MALDI source coupled to an accurate mass, high-resolution hybrid mass spectrometer. MALDI-produced
ions and fragment ions thereof produced in the mass spectrometer may be analyzed and detected by the Orbitrap analyzer at
a maximum mass resolution of 100,000 (FWHM) at m/z 400 with high mass accuracy. An accuracy of ≤2 ppm is achieved by internal mass calibration using lock mass functionality;
using external mass calibration, an accuracy of ≤3 ppm is routinely obtained. External mass calibration of the hybrid mass
spectrometer is performed using a standard calibration mixture of different peptides and matrix components. The instrumental
capabilities are demonstrated for analytical methodologies such as Protein ID using Peptide Mass Fingerprint (PMF) and MS/MS
analyses of small molecule samples. Stability of mass accuracy and signal-to-noise ratio for low samples loads (on plates)
are demonstrated as well as the experimental dynamic range using α-cyano-4-hydroxy cinnamic acid (CHCA) matrix. 相似文献