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1.
2.
This paper deals with the study of the MHD flow of non-Newtonian fluid on a porous plate. Two exact solutions for non-torsionally generated unsteady hydromagnetic flow of an electrically conducting second order incompressible fluid bounded by an infinite non-conducting porous plate subjected to a uniform suction or blowing have been analyzed. The governing partial differential equation for the flow has been established. The mathematical analysis is presented for the hydromagnetic boundary layer flow neglecting the induced magnetic field. The effect of presence of the material constants of the second order fluid on the velocity field is discussed. 相似文献
3.
A closed-form expression is presented to find the location of solid-liquid interface motion in convection-dominated solidification and melting problems. In this regard, the solutions are expressed in terms of the generalized representations of error functions,E (u, v) andF (u, v), which are useful to heat-conduction problems with convective-type boundary conditions. It is demonstrated that for constant surface temperature, the interface solution reduces to the classical Neumann solution. 相似文献
4.
K. C. Malhotra N. Sharma S. S. Bhatt S. C. Chaudhry 《Journal of Thermal Analysis and Calorimetry》1996,46(1):327-330
Thermal behaviour of aryloxides of titanium(IV) of composition TiCln(OAr)4?n (wheren=0→3 and OAr=OC6But-4, OC6H4OMe-4 and OC6H2-Bu 2 t -2,6?Me-4) has been studied by DTA and TG analysis. Multiple decomposition steps have been indicated by thermal weight losses which are both exothermic and endothermic as shown by DTA curves. Based upon the total % loss in weight; during entire decomposition titanium dioxide has been found to be the final residue in each case. 相似文献
5.
Kailash C. Malhotra Brij Bala Neeraj Sharma Subhash C. Chaudhry 《Transition Metal Chemistry》1995,20(4):388-390
Summary Complexes of composition [VOCl2(OC6H4Bu-t-4)] (1) and [VOCl(OC6H4Bu-t-4)2] (2) have been synthesized by the reaction of VOCl3 with equimolar and bimolar amounts, respectively, of 4-t-BuC6H4OSiMe3 in CCl4 and characterized by physio-chemical techniques. The complexes react with -hydroxyaldehydes and ketones such as 2-hydroxybenzaldehyde (salicylaldehyde, salH), and 2-hydroxy-2-phenylacetophenone (benzoin, benzH), 2-hydroxyacetophenone (hapH) and also with the potassium salt of p-chlorobenzohydroxamic acid (KBHACl) in 11 and 12 molar ratios, to yield five- and six-coordinate complexes. 相似文献
6.
Mohammad Shakir Shahul Hameed Farha Firdaus Saji P. Varkey 《Transition Metal Chemistry》1995,20(2):142-143
Summary Adducts of dichlorosulphato bis(1,3-propylenediamine)-metal(II) complexes with dialkyltin dichlorides, [R2Sn(MeCN) 2]2[M(NH(CH2)3NH)2(SO3Cl)2] (M = Cr, Fe, Co, Ni or Cu; R = Me or n-Bu) have been prepared. The positive shift in the symmetric SO3 stretch and splitting of the doubly degenerate (E) modes in their i.r. spectra suggest a covalent linkage for the SO3Cl– group. The adducts are non-electrolytes; magnetic moments and ligand field data suggest that each SO3Cl– group is monodentate, generating an octahedral geometry around the metal ions, except for NiII where tetragonal distortion is observed.Author to whom all correspondence should be directed. 相似文献
7.
Summary The number and positions of the i.r. active modes in ethylenediamine complexes of M(SO3Cl)2 (M = Mn, Fe, Co, Ni or Cu) suggest that the SO3Cl– anion is covalently bound in these non-electrolytic complexes. Magnetic moments and ligand field data suggest that each SO3Cl– group is monodentate, giving an octahedral geometry around the metal ions. 相似文献
8.
Summary Compounds of composition TiCl4–n(OPh)n · 2L (L = monodentate ligand, n = 1–4) have been prepared by the reaction of the parent titanium phenoxides (1 mol) with the ligand (2 mols) and characterized by elemental analysis, molar conductance, molecular weight and i.r. spectral studies. 相似文献
9.
Rosenani A. Haque Abbas Washeel Salman Srinivasa Budagumpi Amirul Al‐Ashraf Abdullah Zena A. Abdul Hameed Al‐Mudaris Amin M. S. Abdul Majid 《应用有机金属化学》2013,27(8):465-473
A series of Ag(I) complexes ( 6 , 7 , 8 , 9 ) derived from imidazol‐2‐ylidenes was synthesized by reacting Ag2O with an o‐, m‐, p‐xylyl or 1,3,5‐triazine‐linked imidazolium salts ( 1 , 2 , 3 , 4 ) and then characterizing these using various spectro‐analytical techniques. Additionally, triazine‐linked bis‐imidazolium salt 5 was characterized using the single‐crystal X‐ray diffraction method. Complexes 6–9 were formed from the N‐heterocyclic carbene ligand precursors 1–3 as PF6‐ salts in good yields. Conversely, salt 5 does not form Ag(I) complex even under various reaction conditions. Using ampicillin as a standard, complexes 6–9 were tested against bacteria strains Escherichia coli and Staphylococcus aureus as Gram‐negative and Gram‐positive bacteria, respectively, showing potent antimicrobial activities against the tested bacteria even at minimum inhibition concentration and bacterial concentration levels. Furthermore, the potential anticancer activities of the reported complexes were evaluated against the human colorectal cancer (HCT 116) cell lines, using 5‐fluorouracil as a standard drug. The highest anticancer activities were observed for complex 8 with an IC50 value of 3.4 μm , whereas the lowest was observed for complex 9 with an IC50 value of 18.1 μm . Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
The double Suzuki cross‐coupling reaction has successfully been applied for the synthesis of 5,5′‐(5‐butoxy‐1,3‐phenylene)bis(2‐chloropyrimidine) with two reactive chloro groups and an alkoxy side chain starting from 2‐chloropyrimidin‐5‐ylboronic acid and 1,3‐dibromo‐5‐butoxybenzene. The reactivity of this dielectrophile was tested by reaction with aniline and phenol, a nitrogen and oxygen nucleophile, respectively. The new dielectrophile would further provide an ideal platform for the construction of large hetero‐atom bridged macrocycles for desired properties and functions in supramolecular and material chemistry. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献