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181.
Amorphous zirconium phosphate (ZP), an inorganic ion exchange material of tetravalent metal acid (tma) salt, is synthesized by the sol-gel method and characterized by elemental analysis (ICP-AES), thermal analysis (TGA, DSC), FT-IR and X-ray diffraction studies. The resistivity of the material to acids, bases and organic solvents is assessed. The sorption behavior of the dyes acriflavin (AF) and brilliant green (BG) toward ZP was studied at 313, 323 and 333 K and the kinetic and thermodynamic parameters evaluated. Adsorption isotherms [Langmuir and Fruendlich], breakthrough capacity and elution behavior of these dyes are also studied. The sorption affinity of dyes towards ZP is BG > AF. 相似文献
182.
Yetta Eagleman Marvin Weber Anurag Chaudhry Stephen Derenzo 《Journal of luminescence》2012,132(11):2889-2896
X-ray excited emission spectra, photoluminescence excitation and emission spectra, optical reflectivity spectra, and pulsed X-ray and optical excited luminescence decay measurements are reported for cerium-doped La2Hf2O7 powders prepared by solid state synthesis. A broad luminescence associated with oxygen vacancies is observed in the region 350–750 nm with a peak around 460 nm. The photoluminescence spectra and the number of oxygen vacancies vary for samples annealed in oxidizing or reducing atmospheres and with the temperature of the synthesis process. Increasing the cerium concentration reduces the oxygen-vacancy-related emission due to the presence of Ce4+. First principles calculations predict that Ce4+ can substitute in Hf sites; this is confirmed from the optical reflectivity spectrum of cerium-doped La2Hf2O7. Photoluminescence excitation and emission spectra characteristic of Ce4+ charge transfer transitions and possibly Ce3+ are also observed. Although trivalent cerium may be present, no emission observed from cerium-doped La2Hf2O7 can be attributed to Ce3+ in La sites. 相似文献
183.
Parmod Kumar Jitendra Pal Singh Yogesh Kumar Anurag Gaur Hitendra K. Malik K. Asokan 《Current Applied Physics》2012,12(4):1166-1172
The present work reports on the synthesis of the Zn1?xMgxO (x = 0, 0.02, 0.05, 0.10, 0.15 and 0.20) samples by sol–gel method and the investigations on their structural, morphological and optical properties. X-ray diffraction (XRD) data analysis confirms the formation of pure ZnO phase below 10% Mg doping and MgO related phases appears in 10% doped sample indicating that phase segregation of MgO starts at x ≥ 0.10 samples. The phase segregation observed through XRD analysis is also supported by results from Scanning Electron Microscopy (SEM), Raman spectroscopy and photoluminescence studies. Furthermore, the enhancement in optical band gap, with Mg doping, from 3.1 ± 0.1 eV to 3.5 ± 0.1 eV has been observed through UV–Vis spectroscopic analysis. Above results have been discussed on the basis of defects level observed through Raman and photoluminscence studies. 相似文献
184.
The complexity of biotherapeutic products implies an ever-increasing list of product quality attributes that need to be monitored and characterized. In addition, the growing interest in implementing process analytical technology in biopharmaceutical production has further increased the testing burden, together with the need for rapid testing that can facilitate real-time or near-real-time decision-making. Capillary electrophoresis (CE) has made a place in biopharmaceutical analysis but is regarded as a low-throughput method, with the instrument dead time constituting more than 80% of the total time of analysis. In this study, the dead time of CE was utilized to analyse 3 mAb samples in a single-CE run. This approach resulted in an up to 77% reduction in the total analysis time and increased the productivity by up to 300%, compared to traditional single CE-ultraviolet runs, without compromising resolution or relative peak areas. Additionally, good method reproducibility was observed. The compatibility of the method has been demonstrated with protein A eluate and cation exchange chromatography fractions. We, thus, propose that sequential injections can be applied for fast and robust CE analysis of biopharmaceuticals. 相似文献
185.
Phool Chandra Shahjad Krishana Kumar Sharma Anurag Verma 《Macromolecular Symposia》2024,413(1):2300110
The concept of macromolecules, which is applied to synthetic and natural polymers, allows for various contemporary polymeric materials and inventive uses. A dynamic structure of macromolecules called the extracellular matrix (ECM) maintains tissues and organs functioning. The cell therapy procedure known as wound healing involves depositing ECM components such as collagen, fibronectin, and laminin. The clinical assessment and management of wounds remain challenging despite the introduction of numerous therapeutic regimens because of their laboriously prolonged treatment requirements and complex wound-healing mechanisms using macromolecules of a specific type, such as proteins, carbohydrates, lipids, and nucleic acids. Additionally, proteins affect the wound site's mechanical characteristics, such as tensile strength, elasticity, and permeability, which impact the effectiveness and success of wound healing. The main goal of this article is to give a current overview of how therapeutic alternatives have evolved using cutting-edge innovative techniques for the healing and treatment of wounds. In this article, we have covered different types of macromolecules, how diet affects the wound, what causes wounds, and how macromolecules can help, and how to treat wounds. 相似文献