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951.
Identifiability of finite mixtures using a new transform 总被引:2,自引:0,他引:2
Khalaf E. Ahmad 《Annals of the Institute of Statistical Mathematics》1988,40(2):261-265
Identifiability of finite mixtures of the following families of distributions are proved: Weibull, normal log, chi, pareto and power function. 相似文献
952.
Hafiz Ghulam Abbas Saeeda Asghar Maqbool Ahmad Shahid 《Journal of Radioanalytical and Nuclear Chemistry》1995,189(1):45-50
A method for labeling of anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb) BW 431/26 is described. For preparations of99mTc-anti-CEA complex, a solution (1 ml) of tetrasodium-1,1,3,3-propanetetetraphosphate dihydrate (2.7 mg), stannous chloride dihydrate (0.12 mg) and sodium chloride (0.2 mg) in 5 ml of 0.9% saline was added to a vial containing monoclonal antibody (2 mg) from mouse (MAb BW 431/26), D-glucitol (2 mg) and sodium sulfate (2 mg) to obtain a clear solution. A quantitative labeling yield of the MAb BW 431/26 was achieved by addition of 5 ml (40.5 mCi, 1.5 Gbq) technetium-99m-pertechnetate (99mTcO4) generator eluate at room temperature within 10 minutes. The radiochemical purity determined by ITLC (Gelman, SG) plates was >95%. 相似文献
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955.
Anam Iqbal Syed Ali Raza Naqvi Rashid Rasheed Asim Mansha Matloob Ahmad Ameer Fawad Zahoor 《Applied biochemistry and biotechnology》2018,185(1):127-139
Bacterial infection poses life-threatening challenge to humanity and stimulates to the researchers for developing better diagnostic and therapeutic agents complying with existing theranostic techniques. Nuclear medicine technique helps to visualize hard-to-diagnose deep-seated bacterial infections using radionuclide-labeled tracer agents. Metronidazole is an antiprotozoal antibiotic that serves as a preeminent anaerobic chemotherapeutic agent. The aim of this study was to develop technetium-99m-labeled metronidazole radiotracer for the detection of deep-seated bacterial infections. Radiosynthesis of 99mTc-metronidazole was carried by reacting reduced technetium-99m and metronidazole at neutral pH for 30 min. The stannous chloride dihydrate was used as the reducing agent. At optimum radiolabeling conditions, ~ 94% radiochemical was obtained. Quality control analysis was carried out with a chromatographic paper and instant thin-layer chromatographic analysis. The biodistribution study of radiochemical was performed using Escherichia coli bacterial infection-induced rat model. The scintigraphic study was performed using E. coli bacterial infection-induced rabbit model. The results showed promising accumulation at the site of infection and its rapid clearance from the body. The tracer showed target-to-non-target ratio 5.57 ± 0.04 at 1 h post-injection. The results showed that 99mTc-MNZ has promising potential to accumulate at E. coli bacterial infection that can be used for E. coli infection imaging. 相似文献
956.
Calcium aluminate (12CaO–7Al2O3) powder was synthesized using three methods, viz. Pechini, coprecipitation, and a new novel facile decomposition route starting from activated alumina and calcium nitrate precursors, then used as a support to prepare a series of 31 wt%Ni/12CaO–7Al2O3 catalysts by deposition–precipitation method. The resultant catalysts were tested in steam pre-reforming of natural gas at 400–550 °C, low steam-to-carbon (S/C) molar ratio of 1.5, and atmospheric pressure. The obtained samples were characterized by Brunauer–Emmett–Teller (BET) analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, temperature-programmed reduction (TPR), temperature-programmed oxidation (TPO), hydrogen chemisorption, and CO2–temperature-programmed desorption (TPD). Experimental results showed that the basicity and morphology of the supports depended significantly on the synthesis method. Calcium aluminate synthesized using the new decomposition procedure showed surface area of 6.23 m2 g?1, while the surface area of those prepared by the Pechini and coprecipitation method were 1.38 and 3.76 m2 g?1, respectively. The catalytic properties of the 31 wt%Ni/12CaO–7Al2O3 catalysts were strongly influenced by the support preparation approach. The highest specific surface area (about 230 m2 g?1), smallest Ni particle size (8.86 nm), and highest nickel dispersion (7.48%) were observed for the catalyst whose support was synthesized by the decomposition method. Even at high gas hourly space velocity (GHSV) of 2 × 105 mL \({\text{g}}^{ - 1}_{\text{catalyst}}\) h?1, this catalyst exhibited around 100% C2H6 and C3H8 conversion at temperature above 500 °C. High catalytic stability during 60 h time on-stream was also shown. The TPO profiles of the spent catalyst demonstrated high resistance to carbon formation. 相似文献
957.
Nahid Nishat Shahnawaz Ahmad Bhat Abdul Kareem Swati Dhyani Abdulrahman Mohammad Azar Ullah Mirza 《Journal of inclusion phenomena and macrocyclic chemistry》2018,92(3-4):395-409
Macro-cyclic ligands from adipic acid, ethylenediamine with diethyloxalate and diethylmalonate and their respective metal complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with macro cyclic ligands (LO) and (LM) L [N,N′-bis(2-aminoethyl)hexanediamide] were synthesized successfully. These metal complexes were characterized by Fourier transform infrared, ultraviolet visible spectrometry, proton nuclear magnetic resonance spectroscopy, and mass Spectrometry, CHNS and thermogravimetric analysis. The elemental analysis confirms the structures for Mn(II), Co(II) and Ni(II) complexes similar to octahedral geometry, Cu(II) complexes as a square planar geometry and Zn(II) complexes in the tetrahedral geometry. The molar conductivities of all the metal complexes were taken in 10?3 M DMSO, and values of all the metal complexes showed their electrolytic nature which indicates the presence of chloride ions. Thermal analysis supports as the metal complexes are thermally stable. The result of antimicrobial activity against various microorganisms confirms that the metal complexes are potent bactericides and fungicides than the ligand. Metal complexes of LO with Cu(II) and Zn(II) were found to be highly active against S. typhimurium than the complexes of LM. 相似文献
Graphical abstract
958.
Wajiha Ahmad Sundus Riaz Nasir Mehmood Ahmad Maryam Hameed Ayesha Naeem 《Natural product research》2018,32(8):968-971
Plant phytochemicals, such as flavonoids are in use for the development of optical biosensor. Benzo[a]pyrene (B[a]P), is a pervasive environmental and dietary carcinogen. A fluorescent assay is developed using plant isolated flavonoid for the detection of B[a]P. High content saponins are excluded from the flavonoid-containing methanolic extract of Corchorus depressus by implying reduction of silver ions by saponins resulting in formation of silver nanoparticles. Isolated plant flavonoids are used to develop a spectrofluorometric assay for the detection of B[a]P. Decrease in the flavonoid fluorescence intensity by B[a]P is found to be based on both static and dynamic quenching. Specificity of the assay for B[a]P was tested for other carcinogens belonging to different classes of compounds. Flavonoids-mediated sensing can be implied for the development of new generation of nanoparticle-based biosensors that can be more sensitive and less susceptible to external factors, such as temperature and humidity. 相似文献
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960.
Analysis of Solvent Effect on Mechanical Properties of Poly(ether ether ketone) Using Nano-indentation 下载免费PDF全文
Tanveer Iqbal Saima Yasin Ahmad Shakeel Hamayoun Mahmood Fahad Nazir Paul F. Luckham 《化学物理学报(中文版)》2018,31(2):211-215
Poly (ether ether ketone)(PEEK) is a high-performance semi-crystalline thermoplastic polymer.Exposure of the polymeric surface to solvents can have a strong effect like softening/swelling of polymeric network or dissolution.In this study, nano-indentation analysis was performed to study the effect of acetone on the surface mechanical properties of PEEK using different exposure time.The experiments were performed with a constant loading rate (10 nm/s) to a maximum indentation displacement (1000 nm).A 30-second hold segment was included at the maximum load to account for any creep effects followed by an unloading segment to 80% unloading.The indentation hardness and the elastic modulus were computed as a continuous function of the penetration displacement in the continuous stiffness mode (CSM) indentation.The experimental data showed that the peak load decreased from ~5.2 mN to ~1.7 mN as exposure time in solvent environment increased from 0 to 18 days.The elastic modulus and the hardness of PEEK samples also displayed a decreasing trend as a function of exposure time in the solvent environment.Two empirical models were used to fit the experimental data of hardness as a function of exposure time which showed a good agreement with the experimental values. 相似文献