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91.
Review of nanofluids for heat transfer applications 总被引:2,自引:0,他引:2
Saeid Vafaei 《中国颗粒学报》2009,7(2)
Research on nanofluids has progressed rapidly since its enhanced thermal conductivity was first repotted about a decade ago,though much controversy and inconsistency have been reported,and insufficient understanding of the formulation and mechanism of nanofluids further limits their applications.This work presents a critical review of research on heat transfer applications of nanofluids with the aim of identifying the limiting factors so as to push forward their further development. 相似文献
92.
廖世俊 《应用数学和力学(英文版)》2008,29(2):223-228
A new modification of false position method for solving nonlinear equations is presented by applying homotopy analysis method (HAM). Some numerical illustrations are given to show the efficiency of algorithm. 相似文献
93.
Vickers hardness and refractive index was determined for Ca–Si–O–N glasses with 14.6–58 e/o N and 19–42 e/o Ca. By applying slow cooling rates, transparent glasses were obtained for compositions near Ca9.94Si10O17.73N8.14, while the majority of the glasses were opaque due to small inclusions of elemental Si and/or Ca-silicide. Determined glass densities varied between 2.80 and 3.25 g/cm3. Hardness was found to vary from 7.3 to 10.1 GPa at a load of 500 g and, respectively increase and decrease linearly with N and Ca content. The refractive index was found to increase linearly with N content from 1.62 to 1.95 and showed no significant dependence on Ca content. 相似文献
94.
For a locally compact semigroup \({\mathcal{S}}\), let \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))\) be the Banach space of all μ-measurable (\(\mu\in M_{a}({\mathcal{S}})\)) functions vanishing at infinity, where \(M_{a}({\mathcal{S}})\) denotes the algebra of all measures in the measure algebra \(M({\mathcal{S}})\) of \({\mathcal{S}}\) with continuous translations. Here, we study right compact multipliers on the Banach algebra \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))^{*}\) equipped with an Arens product. 相似文献
95.
Reza Azadbakht Hassan Keypour Hadi Amiri Rudbari Ali Hossein Mohammad Zaheri Saeid Menati 《Journal of luminescence》2012,132(8):1860-1866
Two new macrocyclic systems (L1, L2) containing two emissive naphthalene were synthesized and characterized. The macrocycles were studied by 1H NMR, 13C NMR, COSY, HMQC, DEPT, microanalysis and mass spectroscopy. The influence of metal cations Na+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+ on the spectroscopic properties of the macrocyclic systems in acetonitrile/DMF 9:1 (v/v) mixtures were investigated by means of absorption and emission spectrophotometry. The macrocycle L1 was found to be as an effective fluorescence sensor for Zn2+ ions. Zn2+ and Cd2+ ions show the most effects on the fluorescence intensity of L2. 相似文献
96.
Javad Zolgharnein Fariborz Riahii Saeid Amani 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(1-2):13-17
The complexation of La(III), Ce(III), Pr(III) and Er(III) with 18-crown-6(18C6), dibenzo-18-crown-6 (DB18C6), dicyclohexano-18-crown-6 (DCY18C6) anddibenzopyridino-18-crown-6 (DBPY18C6) has been studied in dimethylsulfoxide(DMSO) by means of a competitive spectrophotometric method using murexide asa metal ion indicator. The formation constants of the 1 : 1 complexeswere found tovary in the order La(III) > Ce(III) > Pr(III) > Er(III). It was foundthat the structure influences the formation and stability of the resultingcomplexes. The effects ofvarious parameters on complexation are discussed. The order of the stabilityconstants of each lanthanide ion with these macrocycles are18C6 > DC18C6 > DB18C6 > DBPY18C6. 相似文献
97.
The reaction of solution 2,6‐pyridinedicarboxylic acid and 1,10‐phenanthroline ( 1 ) with CrCl3·6H2O led to the complex [Cr(phen)(pydc)(H2O)][Cr(pydc)2]·4H2O ( 2 ) (phen is 1,10‐phenanthroline and pydcH2 is 2,6‐pyridinedicarboxylic acid). 2 was characterized by elemental analysis, IR spectroscopy and single‐crystal structure determination. Crystal data for 2 at ?80 °C: triclinic, space group , a = 818.5(1), b = 1492.2(1), c = 1533.6(2) pm, α = 76.45(1)°, β = 84.22(1)°, γ = 77.99(1)°, Z = 2, R1 = 0.0416. 相似文献
98.
Heidar Raissi Effat Moshfeghi Abraham F. Jalbout Mohammad Saeid Hosseini Mustapha Fazli 《International journal of quantum chemistry》2007,107(9):1835-1845
The molecular structure and intramolecular hydrogen bond energy of 32 conformers of 4‐methylamino‐3‐penten‐2‐one were investigated at MP2 and B3LYP levels of theory using the standard 6–31G** basis set and AIM analyses. Furthermore, calculations for all the possible conformations of 4‐methylamino‐3‐penten‐2‐one in water solution were also carried out at B3LYP/6–31G** level of theory. The calculated geometrical parameters and conformational analyses in gas phase and water solution show that the ketoamine conformers of this compound are more stable than the other conformers (i.e., enolimine and ketoimine). This stability is mainly due to the formation of a strong N? H···O intramolecular hydrogen bond, which is assisted by π‐electrons resonance. Hydrogen bond energies for all conformers of 4‐methylamino‐3‐penten‐2‐one were obtained from the related rotamers method. The nature of intramolecular hydrogen bond existing within 4‐methylamino‐3‐penten‐2‐one has been investigated by means of the Bader theory of atoms in molecules, which is based on topological properties of the electron density. The results of these calculations support the results which obtained by related rotamers method. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
99.
Mohammad Saeid Hejazi Mohammad Hossein Pournaghi‐Azar Esmaeel Alipour Elaheh Dalir Abdolahinia Sanam Arami Hosnieh Navvah 《Electroanalysis》2011,23(2):503-511
In spite of the extensive attention paid on the development of various DNA detection strategies, very few studies have been reported regarding direct detection of DNA sequence and mutation in dsDNA. Here, we describe the feasibility of detection and discrimination of target DNA sequences and single base mutations (SBM) directly in double‐stranded oligonucleotides and PCR products without the need for denaturation of the target dsDNA samples. This goal was achieved by employing a peptide nucleic acid (PNA) chain, self‐assembled on the gold electrode as a probe, which binds to dsDNA and forms PNA‐dsDNA hybrid. 相似文献
100.
Levasseur B Ebrahim AM Bandosz TJ 《Langmuir : the ACS journal of surfaces and colloids》2011,27(15):9379-9386
Mixed oxides Ce(1-x)Zr(x)O(2) prepared by slow coprecipitation in NaOH were tested for NO(2) adsorption in dynamic conditions at room temperature. The samples were characterized before and after exposure to NO(2) by XRD, N(2)-adsorption, thermal analysis, potentiometric titration, and FT-IR. Mixed oxides show a better NO(2) adsorption capacity than the parent materials (CeO(2) and Zr(OH)(4)). This effect is linked to the presence of reduced cerium and oxygen vacancies induced by the addition of Zr(4+) cations to the structure. The results indicate that NO(2) reacts with Ce(3+) to form nitrite and nitrate species on the surface. The NO retention increases with an increase in the Zr(OH)(4) content. A decrease in the density of -OH groups on the surface after the exposure to NO(2), suggests their involvement in reactive adsorption of NO and/or NO(2). From the structural point of view, no real difference was observed on the Ce(1-x)Zr(x)O(2) materials before and after exposure to NO(2). 相似文献