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1.
Paul Kirren Lucile Barka Saher Rahmani Nicolas Bondon Nicolas Donzel Philippe Trens Aurlie Bessire Laurence Raehm Clarence Charnay Jean-Olivier Durand 《Molecules (Basel, Switzerland)》2022,27(13)
(1) Background: Due to human activities, greenhouse gas (GHG) concentrations in the atmosphere are constantly rising, causing the greenhouse effect. Among GHGs, carbon dioxide (CO2) is responsible for about two-thirds of the total energy imbalance which is the origin of the increase in the Earth’s temperature. (2) Methods: In this field, we describe the development of periodic mesoporous organosilica nanoparticles (PMO NPs) used to capture and store CO2 present in the atmosphere. Several types of PMO NP (bis(triethoxysilyl)ethane (BTEE) as matrix, co-condensed with trialkoxysilylated aminopyridine (py) and trialkoxysilylated bipyridine (Etbipy and iPrbipy)) were synthesized by means of the sol-gel procedure, then characterized with different techniques (DLS, TEM, FTIR, BET). A systematic evaluation of CO2 adsorption was carried out at 298 K and 273 K, at low pressure. (3) Results: The best values of CO2 adsorption were obtained with 6% bipyridine: 1.045 mmol·g−1 at 298 K and 2.26 mmol·g−1 at 273 K. (4) Conclusions: The synthetized BTEE/aminopyridine or bipyridine PMO NPs showed significant results and could be promising for carbon capture and storage (CCS) application. 相似文献
2.
Challenges and strategies in the preparation of large‐volume polymer‐based monolithic chromatography adsorbents 下载免费PDF全文
To date, the number of published reports on the large‐volume preparation of polymer‐based monolithic chromatography adsorbents is still lacking and is of great importance. Many critical factors need to be considered when manufacturing a large‐volume polymer‐based monolith for chromatographic applications. Structural integrity, validity, and repeatability are thought to be the key factors determining the usability of a large‐volume monolith in a separation process. In this review, we focus on problems and solutions pertaining to heat dissipation, pore size distribution, “wall channel” effect, and mechanical strength in monolith preparation. A template‐based method comprising sacrificial and nonsacrificial techniques is possibly the method of choice due to its precise control over the porous structure. However, additional expensive steps are usually required for the template removal. Other strategies in monolith preparation are also discussed. 相似文献
3.
The transport of fluids in the semicrystalline polymer, poly(aryl ether ether ketone) (PEEK), was investigated. Both solubility and rate of penetration of toluene into PEEK are markedly increased by the application of an external stress. The induction period (i.e., the time for the sorption to begin) is a function of applied stress as well as temperature and crystallinity. At 22°C in 29% crystalline PEEK the induction period was reduced from more than 2000 h to approximately 10 h whereas the solubility of toluene was increased from 9 to 44 wt % upon the application of an external tensile stress of 30 MPa. A critical stress (i.e., a stress value below which the stress-enhanced effects are not observed) was determined. The critical stress is a strong function of crystallinity and temperature. © 1996 John Wiley & Sons, Inc. 相似文献
4.
Variants of Dynamic Mode Decomposition: Boundary Condition, Koopman, and Fourier Analyses 总被引:3,自引:0,他引:3
Dynamic mode decomposition (DMD) is an Arnoldi-like method based on the Koopman operator. It analyzes empirical data, typically generated by nonlinear dynamics, and computes eigenvalues and eigenmodes of an approximate linear model. Without explicit knowledge of the dynamical operator, it extracts frequencies, growth rates, and spatial structures for each mode. We show that expansion in DMD modes is unique under certain conditions. When constructing mode-based reduced-order models of partial differential equations, subtracting a mean from the data set is typically necessary to satisfy boundary conditions. Subtracting the mean of the data exactly reduces DMD to the temporal discrete Fourier transform (DFT); this is restrictive and generally undesirable. On the other hand, subtracting an equilibrium point generally preserves the DMD spectrum and modes. Next, we introduce an ??optimized?? DMD that computes an arbitrary number of dynamical modes from a data set. Compared to DMD, optimized DMD is superior at calculating physically relevant frequencies, and is less numerically sensitive. We test these decomposition methods on data from a two-dimensional cylinder fluid flow at a Reynolds number of?60. Time-varying modes computed from the DMD variants yield low projection errors. 相似文献
5.
Caleb Acquah Michael K. Danquah John L.S. Yon Amandeep Sidhu Clarence M. Ongkudon 《Analytica chimica acta》2015
The discovery of Systematic Evolution of Ligands by Exponential Enrichment (SELEX) assay has led to the generation of aptamers from libraries of nucleic acids. Concomitantly, aptamer-target recognition and its potential biomedical applications have become a major research endeavour. Aptamers possess unique properties that make them superior biological receptors to antibodies with a plethora of target molecules. Some specific areas of opportunities explored for aptamer-target interactions include biochemical analysis, cell signalling and targeting, biomolecular purification processes, pathogen detection and, clinical diagnosis and therapy. Most of these potential applications rely on the effective immobilisation of aptamers on support systems to probe target species. Hence, recent research focus is geared towards immobilising aptamers as oligosorbents for biodetection and bioscreening. This article seeks to review advances in immobilised aptameric binding with associated successful milestones and respective limitations. A proposal for high throughput bioscreening using continuous polymeric adsorbents is also presented. 相似文献
6.
The adaptation of methods from quantum chemistry and condensed matter theory for studying biological molecules has proved fruitful in developing our understanding of the electronic and conformational structure and thereby the functionality of amino-acids and proteins. Professor Suhai has been at the forefront of these developments and has made contributions in many areas of this vast field of research. In this article, we focus on three such areas, namely, (1) amino acids, (2) bacteriorhodopsin and (3) anti-cancer drugs involving especially Ru and Rh. We show how advances in density functional theory (DFT) have been used to calculate the electronic structure and density in amino-acids so that they can be compared with X-ray diffraction studies. We also demonstrate how ideas from the theory of phase transitions in condensed matter may be applied for studying phase transitions in bacteriorhodopsin, DNA and proteins. Finally, we highlight some of the recent work done in bringing DFT together with quantum chemistry modelling in studying metallopharmaceutical complexes and conformations of peptides. 相似文献
7.
J.S. Maybee 《Applied Mathematical Modelling》1980,4(2):130-132
A methodology for long-term forecasting of smooth approximations to the load duration curve is presented. The forecast results, when the approach is empirically implemented, are extremely good. Finally, while the application is limited to a functional approximation that has previously been used, there is nothing to prevent its being adapted to other specifications. 相似文献
8.
Dr. Yuanyuan Li Dr. Shunjie Liu Huwei Ni Haoke Zhang Dr. Hequn Zhang Clarence Chuah Chao Ma Prof. Kam Sing Wong Prof. Jacky W. Y. Lam Prof. Ryan T. K. Kwok Prof. Jun Qian Prof. Xuefeng Lu Prof. Ben Zhong Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12922-12926
The traditional design strategies for highly bright solid-state luminescent materials rely on weakening the intermolecular π–π interactions, which may limit diversity when developing new materials. Herein, we propose a strategy of tuning the molecular packing mode by regioisomerization to regulate the solid-state fluorescence. TBP-e-TPA with a molecular rotor in the end position of a planar core adopts a long-range cofacial packing mode, which in the solid state is almost non-emissive. By shifting molecular rotors to the bay position, the resultant TBP-b-TPA possesses a discrete cross packing mode, giving a quantum yield of 15.6±0.2 %. These results demonstrate the relationship between the solid-state fluorescence efficiency and the molecule's packing mode. Thanks to the good photophysical properties, TBP-b-TPA nanoparticles were used for two-photon deep brain imaging. This molecular design philosophy provides a new way of designing highly bright solid-state fluorophores. 相似文献
9.
Derrien G Charnay C Zajac J Jones DJ Rozière J 《Chemical communications (Cambridge, England)》2008,(27):3118-3120
Copper-containing mesoporous silica spheres of size in the colloidal range with perfect conservation of pore-ordering, shape and monodispersity and high intra-pore metal dispersion were prepared via a new one-step synthesis and functionalisation route. 相似文献
10.
Petiot P Charnay C Martinez J Puttergill L Galindo F Lamaty F Colacino E 《Chemical communications (Cambridge, England)》2010,46(46):8842-8844
The synthesis of a new hydrophilic ammonium-based poly(ethylene glycol)-ionic liquid (PEG-IL) is reported; the structure was assigned by NMR ((1)H, (13)C) and MALDI mass spectrometry. The viscosity and thermal stability were also studied, as well as its polarity. Its application as an alternative solvent in the synthesis of dipeptides under microwave irradiation is also described. 相似文献