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91.
Arif Rafiq Nazir Ahmad Mir Farooq Ahmad .Mathematics Department COMSATS Institute of Information Technology Islamabad Pakistan .Centre for Advanced Studies in Pure Applied Mathematics Bahauddin Zakariya University Multan Pakistan 《应用数学和力学(英文版)》2007,(7)
In account of the famous ebyev inequality,a rich theory has appeared in the literature.We establish some new weighted ebyev type integral inequalitíes.Our proofs are of independent interest and provide new estimates on these types of inequalities. 相似文献
92.
S. Pervez A. Mushtaq N. Arif Z. H. Chohan 《Journal of Radioanalytical and Nuclear Chemistry》2003,257(2):417-420
Bone seeking radiopharmaceuticals such as ethylenediaminetetramethylene phosphonate (EDTMP) complexes of 153Sm and 166Ho are receiving considerable attention for therapeutic treatment of bone metastases. Rhenium-188 has both beta-particle emissions for a therapeutic effect and gamma-emissions for imaging and it is available from an in-house generator system similar to the current 99mTc generator, which makes it convenient for clinical use. The preparation of 188Re-EDTMP is described using 188Re, which was obtained from the alumina-based 188W/188Re generator. Dependence of the radiolabeling yield of 188Re-EDTMP on reducing agent concentration, EDTMP concentration, incubation time, pH and addition of carrier was examined. In the case of optimum conditions, the radiolabeling yields of 188Re-EDTMP were ~98% for carrier-free as well as carrier-added 188Re. The addition of ascorbic acid plays an important role in the stability of carrier-free as well as carrier-added 188Re-EDTMP preparations. The biodistribution of carrier-free and carrier-added 188Re-EDTMP compounds in rats was also studied. The results show that 188Re (carrier-added)-EDTMP is a potential bone pain palliation radiopharmaceutical due to its high skeletal uptake, rapid blood clearance and relatively low soft tissue absorption. 相似文献
93.
Zekeriyya Bahadır Volkan Numan Bulut Arif Mermer Neslihan Demirbaş Celal Duran Mustafa Soylak 《Journal of the Iranian Chemical Society》2018,15(6):1347-1354
A selective separation and preconcentration method for the determination of gold ions in water and ore samples has been developed using dispersive liquid–liquid microextraction, followed by flame atomic absorption spectrometry. 4-Ethyl-1(2-(4-(4-nitrophenyl)piperazin-1-yl)acetyl)thiosemicarbazide) (NPPTSC) has been used for the first time as new chelating reagent. A mixture of ethanol (dispersive solvent) and carbon tetrachloride (extraction solvent) was used. Some parameters affecting the extraction procedure including the type and volume of the extracting and dispersive solvents, HNO3 concentration, the chelating agent amount, volume of sample, and foreign ions have optimized. Also, the complex formation between gold ions and the ligand has been investigated in a methanol–water solution (1:1) using UV–visible spectrometry. The spectrophotometric titration data showed that of Au–NPPTSC complex composition was found to be 3:2. After optimizing the instrumental and experimental parameters, we achieved a detection limit of 1.5 µg L?1, a preconcentration factor of 50, and a linear dynamic range of 10.0–400.0 µg L?1. The relative standard deviation obtained 2.1% at 50 µg L?1 for gold ions (n = 10). The proposed method was successfully performed for the determination of gold in certified reference material, environmental water, and ore samples. 相似文献
94.
The reactions of RuH3[P(C6H5)3]
3
–
with Cr(CO)3(CH3CN)3, Mo(CO)3 (diglyme), or W(CO)3(C3H2CN)3 resulted in the formation of the appropriate [(H5C6)3P]3Ru(-H)3
M(CO)
3
–
complexes, which have been characterized analytically, spectroscopically, and in one case (M = Cr) by an X-ray diffraction study of the K [N(C2H4OC2H4OCH3)3]+ salt. This complex crystallizes in the triclinic space group Pl witha = 13.666(6),b= 13.7901(7),c = 18.147(8) A,a = 93.23(3)°, = 94.07(4)° = 90.43(4)°, andV = 3405.6 A3 for Z = 2. Final discrepancy indices ofR = 0.048 and Rù = 0.056 were obtained. The hydride ligands, all of which could be located and their positional coordinates refined, completed local pseudo-octahedral coordination about both the ruthenium and thechromium centers. The Ru-H bonds are significantly shorter than the Cr-H ones, 1.65(4) vs. 1.92(4) A, and the Ru-Cr bond distance is 2.5474(9) A. 相似文献
95.
Mononuclear Ni(II), Co(II), and Zn(II) complexes of the bppppa (N,N-bis[(6-phenyl-2-pyridyl)methyl]-N-[(6-pivaloylamido-2-pyridyl)methyl]amine) ligand have been synthesized and characterized by X-ray crystallography, 1H NMR, UV-vis (Ni(II) and Co(II)) and infrared spectroscopy, and elemental analysis. Each complex has the empirical formula [(bppppa)M](ClO4)2 (M = Ni(II), 2; Zn(II), 3; Co(II), 4) and in the solid state exhibits a metal center having a coordination number of five; albeit, the cation of 2 also has a sixth weak interaction involving a perchlorate anion. Treatment of [(bppppa)Ni](ClO4)2 (2) with 1 equiv of acetohydroxamic acid results in the formation of [(bppppa)Ni(HONHC(O)CH3)](ClO4)2 (1), a novel Ni(II) complex having a coordinated neutral acetohydroxamic acid ligand. In 1, one phenyl-appended pyridyl donor of the bppppa chelate ligand is dissociated from the metal center and acts as a hydrogen bond acceptor for the hydroxyl group of the bound acetohydroxamic acid ligand. Treatment of 1 with excess water results in the formation of 2 and free acetohydroxamic acid. We hypothesize that this reaction occurs due to disruption of the intramolecular hydrogen bonding interaction involving the bound acid. In this series of reactions, the bppppa ligand exhibits behavior reminiscent of a type III hemilabile ligand in terms of one phenylpyridyl donor. Treatment of 3 or 4 with acetohydroxamic acid results in no reaction, indicating that the bppppa-ligated Ni(II) derivative 2 exhibits unique coordination chemistry with respect to reaction with acetohydroxamic acid within this series of complexes. We attribute this reactivity to the ability of the bppppa-ligated Ni(II) center to adopt a pseudo-octahedral geometry, whereas the Zn(II) and Co(II) complexes retain five coordinate metal centers. 相似文献
96.
Flexible donor ligands like 1,2-bis(3-pyridyl)ethyne or 1,4-bis(3-pyridyl)-1,3-butadiyne self-assemble into discrete supramolecules instead of infinite networks upon combination with organoplatinum 90, 120, and 180 degree acceptor units. These systems are unique examples of versatile pyridine donors adjusting their bonding directionality to accommodate rigid platinum acceptors in the formation of closed macrocycles. 相似文献
97.
98.
Mohammad Wasim Mohammad Arif Mohammad S. Iqbal 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):249-254
Researcher’s interest is increasing worldwide to study the role of trace elements in brain tissues. This paper discusses the application of k 0-instrumental neutron activation analysis to study the distribution of trace elements in seven different anatomical regions of goat brain. These regions include cerebellum, cerebrum, medulla oblongata, meninges, midbrain, pons and thalamus. The analysis protocol followed 1 h irradiation at 10 MW material testing type nuclear research reactor with nominal thermal neutron flux of 2 × 1013 cm?2 s?1. A total of 14 elements, namely Br, Co, Cr, Eu, Fe, Hg, K, Na, Rb, Sb, Sc, Se, Tb and Zn were determined in all parts. Reliability of the method was assessed by analyzing biological reference material IAEA-336 (lichen). On comparing the analytical results with the healthy human brain data, it showed that eight elements (Eu, K, Na, Rb, Sb, Sc, Se, Tb) were found with relatively higher elemental concentrations in human brain. Principal component analysis revealed distribution of seven parts in different three groups having similar elemental concentrations of elements. 相似文献
99.
Mohammad Wasim Muhammad Daud Mohammad Arif Rameez ul-Islam Sajid Iqbal Yasir Anwar 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):653-659
In the under developed countries, the people of far-flung rural areas still depend to a large extent upon herbal medicines.
At the foundation of usage of herbal medicine is the experience of thousands of years. The present paper deals with the characterisation
of exotic fruits for essential and toxic elements. The samples include Morus nigra, Morus alba, Salvadora persica and Carissa opaca (from low and high altitude). Two standardizations of neutron activation analysis, that is, semi-absolute k
0-instrumental neutron activation analysis (k
0-INAA) and epithermal neutron activation analysis (ENAA) were employed for the quantification of elements. The analysis methodologies
were validated by analyzing the IAEA-336 (lichen) and NIST-SRM-1572 (citrus leaves). Sixteen elements including Br, Ca, Cl,
Co, Cr, Fe, I, K, Mg, Mn, Na, Rb, Sb, Sc Sr, and Zn were determined in all samples. Daily intakes of various elements from
the samples were measured and compared with the dietary reference intakes. Additionally, principal component analysis was
performed to extract information regarding samples and elements. 相似文献
100.
Homotopy perturbation method is used to solve specific second order ordinary differential equations and tested for different examples. The results obtained demonstrate efficiency of the proposed method. 相似文献