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231.
232.
Calcium 5-aminoisophthalate {[Ca(AIP)(OH2)4](H2O)} proportional, variant (1), synthesized from Ca(OH)2 and H2AIP, exists as a double helix. Hydrogen-bonding interactions between metal-bound water molecules, carboxylate oxygen, and the -NH2 group result in the formation of a supramolecular assembly, where the double helices are connected to each other to form hexagonal channels filled with water molecules. 相似文献
233.
234.
Wang C Soice NP Ramaswamy S Gagnon BA Umana J Cotoni KA Bian N Cheng KS 《Journal of chromatography. A》2007,1155(1):74-84
Agarose-based anion-exchangers (e.g. quaternary amine, Q) have been widely used in monoclonal antibody flow-through purification to remove trace levels of impurities. Such media are often packed in a large column and the operation is usually robust but with limited throughput due to the compressibility of agarose and consequentially low bed permeability. In order to address this limitation, cored Q beads consisting of a rigid core and a thin agarose gel coating were developed and evaluated for protein flow-through chromatography. Using laboratory-scale columns it was found that, the cored beads indeed provide significantly enhanced rigidity and flow permeability relative to conventional homogeneous agarose resins. Depending on the structure and size of the cored beads, the permeability was 2-4-fold higher than that of a commonly used commercial agarose resin. Good virus and host cell protein clearance was achieved with the cored Q beads even at increased flow velocities. In addition, the impermeable core allows for more efficient use of buffers without loss of useful capacity in polishing applications. Process analyses based upon the experimental data demonstrated that the enhanced permeability achieved with the cored beads can significantly improve process throughput and economics. 相似文献
235.
The first cubic zinc phosphonate [tBuPO(3)Zn(2-apy)](4) (1) whose core resembles the D4R SBU of zeolites, has been synthesised from a reaction between zinc acetate, tert-butylphosphonic acid and 2-aminopyridine at room temperature; the X-ray structure determination reveals that the molecules of , which crystallise in the tetragonal I4(1)/a space group with crystallographically imposed 4 symmetry, form a 3-D supramolecular assembly aided by N-H...O hydrogen bonding. 相似文献
236.
We report a general strategy for the spontaneous segregation of electron-rich and electron-poor pi-conjugated moieties using mutually phobic aliphatic fluorocarbon-hydrocarbon interactions. 相似文献
237.
238.
239.
N. Janani S. Ramakumar L. Dhivya C. Deviannapoorani K. Saranya Ramaswamy Murugan 《Ionics》2011,17(7):575-580
Polycrystalline cubic Li7La3Zr2O12 (LLZ) with garnet-related type structure has been synthesized at 700 °C by modified sol–gel processes using citric acid as
organic complexing agent and butan-1-ol or propan-2-ol as surface active agent. Thermal analysis (thermogravimetric/differential
thermal analysis) indicated that the gel must be annealed at around 700 °C to completely remove the organic solvent. X-ray
powder diffraction, X-ray fluorescence, and scanning electron microscopic investigations revealed that Al may not be essential
to form cubic-phase LLZ; however, the addition of Al2O3 led to enhanced sintering of LLZ. 相似文献
240.
Ojas Mahapatra Shivaraman Ramaswamy N. Satya Vijaya Kumar B. Brabu Angeline Littleflower C. Gopalakrishnan 《Colloid Journal》2011,73(5):662-667
Zinc oxide nanostructures were prepared by a simple wet chemical procedure using zinc acetate and sodium hydroxide as precursors.
The process was subjected to quenching treatment and the effect of the treatment on the formation of the nanostructures was
studied using atomic force and scanning electron microscopies. The change in crystal structure of the nanostructures due to
quenching was studied using an X-ray diffractometry that established that physical and structural properties of the nanostructures
were largely influenced by the quenching treatment. 相似文献