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141.
L. F. Yang Q. S. Li A. Y. T. Leung Y. L. Zhao G. Q. Li 《European Journal of Mechanics - A/Solids》2002,21(6):104
Linear and non-linear peaky fuzzy numbers and their arithmetic operations are constructed for the analysis of engineering structures with fuzzy characteristic quantities. Fuzziness of the corresponding quantities is consistently incorporated into the functional of the total potential energy. A set of deterministic recursive equations is obtained as the alternative expressions of the fuzzy variational principle by means of the second-order perturbation technique. The fuzzy Ritz method and the fuzzy finite element method are presented as the applications of the fuzzy variational principle. Accordingly, the roundabout procedures frequently used in the formulations of the fuzzy finite element method are avoided. A benchmark problem of a bending beam with fuzzy Young's modulus under fuzzy external loading is solved by the developed fuzzy numerical methods. Numerical examples show that results determined by these two fuzzy methods are both little conservative, and are in good agreement with those obtained by the analytical method. Moreover, the fuzzy Ritz method or the fuzzy finite element method can provide more valuable information than the conventional deterministic methods. 相似文献
142.
Sheng Lin Wei Gao Zeru Tian Chao Yang Lihua Lu Jean-Louis Mergny Chung-Hang Leung Dik-Lung Ma 《Chemical science》2015,6(7):4284-4290
A series of luminescent iridium(iii) complexes were synthesised and evaluated for their ability to act as luminescent G-quadruplex-selective probes. The iridium(iii) complex 9 [Ir(pbi)2(5,5-dmbpy)]PF6 (where pbi = 2-phenyl-1H-benzo[d]imidazole; 5,5-dmbpy = 5,5′-dimethyl-2,2′-bipyridine) exhibited high luminescence for G-quadruplex DNA compared to dsDNA and ssDNA, and was employed to construct a G-quadruplex-based assay for protein tyrosine kinase-7 (PTK7) in aqueous solution. PTK7 is an important biomarker for a range of leukemias and solid tumors. In the presence of PTK7, the specific binding of the sgc8 aptamer sequence triggers a structural transition and releases the G-quadruplex-forming sequence. The formation of the nascent G-quadruplex structure is then detected by the G-quadruplex-selective iridium(iii) complex with an enhanced luminescent response. Moreover, the application of the assay for detecting PTK7 in cellular debris and membrane protein extract was demonstrated. To our knowledge, this is the first G-quadruplex-based assay for PTK7. 相似文献
143.
碱金属钾对Ni基催化剂纤维素水蒸气气化活性的影响 总被引:2,自引:0,他引:2
碱金属钾对Ni基催化剂纤维素水蒸气气化活性的影响 《燃料化学学报》2015,43(12):1433-1438
采用两段式催化气化方式研究了生物质热解气化过程中碱金属的挥发对Ni基催化剂活性的影响。实验结果表明,负载K盐的纤维素水蒸气催化气化过程中,K挥发后会在催化剂表面沉积,而少量K的存在和表面沉积不但能够提高镍基催化剂的抗积炭能力,而且有助于提高其催化活性,产生更多的氢气。然而纤维素中K的浓度过大,将会抑制Ni基催化剂的效果;K在催化剂上的沉积随催化剂循环次数的增加而增加,K的含量愈高,对催化剂的抑制效果愈明显,从而缩短了催化剂的使用寿命。 相似文献
144.
Dual Esterase‐ and Steroid‐Responsive Energy Transfer Modulation of Ruthenium(II) and Rhenium(I) Complex Functionalized Gold Nanoparticles
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Dr. Frankie Chi‐Ming Leung Dr. Vonika Ka‐Man Au Dr. Hai‐Ou Song Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16448-16454
A number of adamantane‐containing ruthenium(II) and rhenium(I) complexes have been synthesized, characterized, and noncovalently functionalized with β‐cyclodextrin‐capped gold nanoparticles (β‐CD–GNPs) through the host–guest interaction between cyclodextrin and adamantane. The resultant nanoconjugates have been characterized by transmission electron microscopy (TEM), energy‐dispersive X‐ray analysis (EDX), and 2D ROESY 1H NMR experiments. The Förster resonance energy transfer (FRET) properties of the nanoconjugates can be modulated by both esterase‐accelerated hydrolysis and competitive displacement of steroid, by monitoring the emission intensity and luminescence lifetime. The FRET efficiencies are found to vary with the nature of the chromophores and the length of the spacer between the transition metal complexes and the GNPs. This work constitutes a “proof‐of‐principle” assay method for the dual‐functional detection of important classes of biomolecules, such as enzymes and steroids. 相似文献
145.
Inside Back Cover: A Multifunctional Bimetallic Molecular Device for Ultrasensitive Detection,Naked‐Eye Recognition,and Elimination of Cyanide Ions (Chem. Eur. J. 37/2015)
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146.
147.
A laser-Doppler velocimeter is used in the measurement of high-temperature gas flows. A two-stage fluidization particle generator provides magnesium oxide particles to serve as optical scattering centers. The one-dimensional dual-beam system is frequency shifted to permit measurements of velocities up to 300 meters per second and turbulence intensities greater than 100 percent.Exiting flows from can-type gas turbine combustors and burners with pre-mixed oxy-acetylene flames are described in terms of the velocity, turbulence intensity, and temperature profiles.The results indicate the influence of the combustion process on turbulence.List of Symbols
A
exit area of combustor or burner (m2)
-
A/F
mass air-fuel ratio
-
D
exit diameter of combustor or burner (m)
-
M
mass flow rate of gases (kg/s)
-
N
D
number of Doppler bursts used in each velocity measurement
-
Q
volumetric flow rate at T
r
(m3/s)
-
R
exit radius of combustor or burner (m)
-
R
1/2
distance from centerline to radius where the velocity is one-half of the local centerline velocity (m)
- Re
exit Reynolds number based on cold flow, QD/A
-
r
distance from centerline of flow (m)
-
T
temperature (°C)
-
T
CL
centerline temperature (°C)
-
T
r
inlet (cold) air temperature of combustor or burner (°C)
- T.I.
turbulence intensity,
-
mean velocity (m/s)
-
U
i
instantaneous velocity individually realized by LDV (m/s)
-
mean velocity at centerline of flow (m/s)
-
mean square velocity fluctuation (m2/s2
-
x
distance along centerline downstream of exit (m)
-
absolute viscosity at T
r
(kg/(ms))
-
density at T
r
(kg/m3) 相似文献
148.
149.
Wai-Man Cheung Guo-Cang Wang Wa-Hung Leung 《Journal of organometallic chemistry》2011,696(25):4007-4010
Treatment of [Ru(CHR)Cl2(PCy3)2] (Cy = cyclohexyl) with Tl[N(Pr2iPO)2] and AgLOEt (LOEt− = [CpCo{P(O)(OEt)2}3]−) afforded the Ru carbene complexes [Ru(CHPh)(PCy3)Cl{N(Pr2iPO)2}] (1) and [LOEtRu(CHR)(PCy3)Cl] (2), respectively. Chloride abstraction of complex 2 with TlPF6 in MeCN afforded [LOEtRu(CHPh)(PCy3)(MeCN)][PF6] (3). Complexes 1 and 2 are capable of catalyzing ring-closing metathesis of diethyl 1,2-diallylmalonate. The crystal structure of complex 2 has been determined. 相似文献
150.