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排序方式: 共有166条查询结果,搜索用时 15 毫秒
1.
Mumtaz Khan T. Jabbar M. Asif M. I. Anjum M. Dilband K. Khan A. Jabbar W. Arshed 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):577-582
Technetium (99mTc), a decay product of molybdenum (99Mo), is employed as radioisotope in nuclear medicine. Several practical devices known as generators are commercially available which enable the user to separate the daughter from the parent radionuclide. The present study is focused on quality control of chromatographic technetium generator. A properly constructed generator should comply with international requirements of radionuclide purity of 90Sr/99Mo ≤ 6 × 10?8 and 89Sr/99Mo ≤ 6 × 10?7. For this purpose an analytical method was optimized to quantify radiostrontium (89Sr and 90Sr) in sodium molybdate [Na 2 99 MoO4] solution, a fission product used for 99Mo/99mTc generators. Dowex 1 × 8 and alumina were used in sequence followed by tributyl phosphate extraction for radiostrontium separation. Cerenkov measurement of 89Sr and 90Sr (through its descendent 90Y) was performed using Perkin Elmer Tricarb LSA 3170 with detection efficiency of 42 and 14 %, respectively. Since efficiency of Cerenkov counting is sensitive to presence of color, spectral index of sample was used to correct the counting efficiency. The chemical recovery for strontium was 22 % and for yttrium was 80 % as determined by inductively coupled plasma optical emission spectrometry. Lower limit of detection was found to be 6.3 and 14.4 Bq L?1 for 90Sr and 89Sr, respectively with 60 min counting time. Hence method can be applied successfully to analyze 89,90Sr in fission molybdenum used as radiopharmaceutical with a relative error of <10 %. 相似文献
2.
Wang Haoran Wasim Akhtar Lalit Mohan Nainwal Sumit Kumar Kaushik Mymoona Akhter Mohammad Shaquiquzzaman Mohammad Mumtaz Alam 《Journal of heterocyclic chemistry》2020,57(9):3350-3360
Thirteen new benzimidazole pendant cyanopyrimidine derivatives were synthesized. The compounds were synthesized through multistep reaction protocol. The structures of synthesized derivatives were studied by EI-MS, 1H NMR, FT-IR and elemental analysis. All the compounds were studied for their anticancer activity at National Cancer Institute. Except compound 7j , all the compounds unveiled cytotoxicity against cancer cells. The most active compound 7a had shown highest value of growth inhibition of 88.44% and 84.19% against HOP-92 and T-47D cancer cell lines. 相似文献
3.
Muhammad Omer Iqbal Muhammad Masood Ahmed Shafia Arshad Usman Javaid Imran Ahmad Khan Majid Manzoor Shumaila Andleeb Romana Riaz Shaukat Hussain Munawar Zahid Manzoor Asma Mumtaz 《Molecules (Basel, Switzerland)》2022,27(3)
Alhagi camelorum (AC) is an old plant with a significant therapeutic value throughout Africa, Asia, and Latin America. The overuse of cisplatin (Cis > 50 mg/m2) is associated with observed nephrotoxicity, ototoxicity, gastrotoxicity, myelosuppression, and allergic reactions. Remedial measures are needed for the protection of nephrotoxicity against cisplatin. Thus, we investigated the nephroprotective effects of AC plant extract to prevent cisplatin-induced nephrotoxicity in albino Wistar rats. The presence of polyphenols, phenolic compounds, tannins, and saponins was revealed during phytochemical investigation, and a significantly intense antioxidant activity was recorded. There were no toxicological symptoms in the treated rats, and no anatomical, physiological, or histological abnormalities were found compared to the control rats. The results of correcting cisplatin-induced nephrotoxicity revealed that the extract has a significant ability to treat kidney damage, with most parameters returning to normal after only three weeks of therapy. It is concluded that co-administration of cisplatin with AC extract showed exceptional nephroprotective effects at a dose of 600 mg/kg for Cis-induced nephrotoxicity. 相似文献
4.
5.
We report on the development and testing of a compact laser tweezers Raman spectroscopy (LTRS) system. The system combines optical trapping and near-infrared Raman spectroscopy for manipulation and identification of single biological cells in solution. A low-power diode laser at 785 nm was used for both trapping and excitation for Raman spectroscopy of the suspended microscopic particles. The design of the LTRS system provides high sensitivity and permits real-time spectroscopic measurements of the biological sample. The system was calibrated by use of polystyrene microbeads and tested on living blood cells and on both living and dead yeast cells. As expected, different images and Raman spectra were observed for the different cells. The LTRS system may provide a valuable tool for the study of fundamental cellular processes and the diagnosis of cellular disorders. 相似文献
6.
Broadly tunable phase-stable single-frequency terahertz radiation is generated with an optical heterodyne photomixer. The photomixer is excited by two near-infrared CW diode lasers that are phase locked to the stabilized optical frequency comb of a femtosecond titanium:sapphire laser. The terahertz radiation emitted by the photomixer is downconverted into RF frequencies with a waveguide harmonic mixer and measurement-limited linewidths at the Hertz level are demonstrated. 相似文献
7.
The dielectric properties of Cu0.5Tl0.5Ba2Ca3Cu4O12−δ superconductor samples were studied at 79 and 290 K by means of capacitance (C) and conductance (G) measurements with the test frequency (f) in the range of 10 kHz to 10 MHz. A negative capacitance (NC) phenomenon has been observed, which is most likely arising due to higher Fermi level of ceramic superconductor samples than metal electrodes. Also the NC may be due to the space charge located at the multiple insulator–superconductor interfaces (grain boundaries) in the materials. The negative dielectric constant (ε′) and loss factor (tan δ) show strong dispersion at low frequencies. The lower thermal agitation at 79 K may enhance the polarizability and hence the dielectric constants (ε′ and ε″). 相似文献
8.
The synthesis of several new polyfunctionally substituted fused pyrazoles via reaction of 5‐amino‐3‐methylthio‐1H‐pyrazole‐4‐carboxylate ( 2 ) with different reagents is described. 相似文献
9.
M. G. Syed Basheer Ahamed V. S. Nagarethinam A. R. Balu A. Thayumanavan K. R. Murali C. Sanjeeviraja M. Jayachandran 《Crystal Research and Technology》2010,45(4):421-426
ZnSe films were deposited on glass substrates keeping the substrate temperatures, at room temperature (RT), 75, 150 and 250 °C. The films have exhibited cubic structure oriented along the (111) direction. Both the crystallinity and the grain size increased with increasing deposition temperature. A very high value of absorption co‐efficient (104 cm‐1) is observed. The band gap values decrease from a value of 2.94 eV to 2.69 eV with increasing substrate temperature. The average refractive index value is in the range of 2.39 – 2.41 for the films deposited at different substrate temperatures. The conductivity values increases continuously with temperature. Laser Raman spectra showed peaks at 140.8 cm‐1, 246.7 cm‐1and 204.5 cm‐1which are attributable to 2TA LO phonon and TO phonon respectively. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Muhammad Mumtaz Anne de Cuendias Jean‐Luc Putaux Eric Cloutet Henri Cramail 《Macromolecular rapid communications》2006,27(17):1446-1453
Summary: The synthesis of PEDOT nanoparticles and vesicles by dispersion polymerization in a methanol/water mixture (3/2, v/v) is reported, using either ammonium persulfate or iron(III) p‐toluenesulfonate as oxidants and α‐EDOT‐PEO as a reactive stabilizer. The influence of the oxidant as well as the α‐EDOT‐PEO molar mass and concentration on the core‐shell particle morphology and conductivity properties have been investigated. PEDOT particles with conductivities up to 1.5 × 10−2 S · cm−1 have been obtained in high yield.