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排序方式: 共有242条查询结果,搜索用时 15 毫秒
121.
YanFeng Yue XiaoGuang Sun Richard T. Mayes Jungseung Kim Pasquale F. Fulvio ZhenAn Qiao Suree Brown Costas Tsouris Yatsandra Oyola Sheng Dai 《中国科学:化学(英文版)》2013,56(11):1510-1515
Polymer-coated mesoporous carbon nanocomposites were prepared from the immobilization of acrylonitrile and acrylic acid copolymers with divinylbenzene as a crosslinker onto a mesoporous carbon framework. High surface areas were maintained after polymerization with accessible porosity. This functional nanocomposite was tested as an adsorbent for uranium from high salinity solutions. Uranium adsorption results have shown that the adsorption capacities are strongly influenced by the density of the amidoxime groups and the specific surface area. 相似文献
122.
Maxwell J. Robb Sung‐Yu Ku Fulvio G. Brunetti Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2013,51(6):1263-1271
Natural dyes and pigments like indigo and its derivatives valued for their bright colors and photochemical stability has been used since antiquity. Recently, the need for better performing materials in the organic electronics field has inspired a resurgence of these historical molecules and their subsequent transformation into new families of π‐conjugated building blocks used to construct new (macro)molecular semiconductors. This Highlight will explore the renaissance of notable building blocks including diketopyrrolopyrrole, (iso)indigo, benzodipyrrolidone, and benzodifuranone, as well as nonfullerene acceptor structures 9,9′‐bifluorenylidene and quinacridone. In addition, as the organic electronics field continues to evolve, the design of molecules with precise structure and function embodies a new paradigm for the next generation of materials. Representative examples will be described that embrace this new model and point the direction for advanced technologies. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
123.
Nitrogen adsorption isotherm measured at ?196 °C for a macroporous α-alumina (α-Al2O3) is reported. This isotherm is compared with the previously reported adsorption data measured on LiChrospher 1000 silica and with available reference isotherms measured at moderate and high relative pressures on macroporous aluminas. The isotherm reported in this work for α-Al2O3 and that recorded previously on LiChrospher 1000 silica were used as reference data for adsorption characterization of ordered and disordered mesoporous aluminas by α s -plot analysis and pore size analysis. It is shown that both reference isotherms provide almost identical adsorption characteristics of the aforementioned mesoporous aluminas, indicating that the available reference data for the silica surface are also suitable for adsorption analysis of alumina-based materials. 相似文献
124.
Dr. Fulvio G. Brunetti Helena Isla Dr. Juan Aragó Prof. Dr. Enrique Ortí Dr. Emilio M. Pérez Prof. Dr. Nazario Martín 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(30):9843-9848
The supramolecular modification of planar graphene with the geometrically mismatched, curved 9,10‐di(1,3‐dithiole‐2‐ylidene)‐9,10‐dihydroanthracene (exTTF) molecule is demonstrated. The exTTF–graphene interaction is governed by π–π and CH–π interactions, with a negligible contribution from charge transfer. We amplified these weak forces through multivalent gold nanoparticles. Our results show that planarity is not a prerequisite for recognition motifs for graphene. 相似文献
125.
126.
Guido Montagna Mauro Moretti Oreste Nicrosini Fulvio Piccinini 《The European Physical Journal C - Particles and Fields》1998,2(3):483-496
The production of an intermediate-mass Higgs boson in processes of the kind fermions at the energies of future linear colliders is studied. The recently developed and fully automatic algorithm/code
ALPHA is used to compute the tree-level scattering amplitudes for the reactions . The code has been interfaced with the Monte Carlo program HIGGSPV/WWGENPV, properly adapted to 6-fermion production, in order to provide realistic results, both in the form of cross sections and
event samples at the partonic level. Phenomenological results, that incorporate the effects of initial-state radiation and
beamstrahlung, are shown and commented, emphasizing the potentials of full six-fermion calculations for precise background
evaluation as well as for detailed studies of the fundamental properties of the Higgs particle.
Received: 22 May 1997 / Published online: 20 February 1998 相似文献
127.
Polyaminopolycarboxylic acids are a well known class of ligands employed for metal ion complexation. Despite the large commercial availability, reports of their use as substrates for direct structural modifications are rare. Herein we report a simple and efficient protocol for the preparation of substituted polyaminopolycarboxylic ligands relying on a one-pot N-alkylation-Stevens rearrangement cascade. 相似文献
128.
Lagrangian and Eulerian pressure field evaluation of rod-airfoil flow from time-resolved tomographic PIV 总被引:1,自引:0,他引:1
This work investigates the rod-airfoil air flow by time-resolved Tomographic Particle Image Velocimetry (TR-TOMO PIV) in thin-light
volume configuration. Experiments are performed at the region close to the leading edge of a NACA0012 airfoil embedded in
the von Kármán wake of a cylindrical rod. The 3D velocity field measured at 5 kHz is used to evaluate the instantaneous planar
pressure field by integration of the pressure gradient field. The experimental data are treated with a discretized model based
on multiple velocity measurements. The time separation used to evaluate the Lagrangian derivative along a fluid parcel trajectory
has to be taken into account to reduce precision error. By comparing Lagrangian and Eulerian approaches, the latter is restricted
to shorter time separations and is found not applicable to evaluate pressure gradient field if a relative precision error
lower than 10% is required. Finally, the pressure evaluated from tomographic velocity measurements is compared to that obtained
from simulated planar ones to discuss the effect of 3D flow phenomena on the accuracy of the proposed technique. 相似文献
129.
Ylenia Pieracci Roberta Ascrizzi Valentina Terreni Luisa Pistelli Guido Flamini Laura Bassolino Flavia Fulvio Massimo Montanari Roberta Paris 《Molecules (Basel, Switzerland)》2021,26(13)
Cannabis sativa L. is an annual species cultivated since antiquity for different purposes. While, in the past, hemp inflorescences were considered crop residues, at present, they are regarded as valuable raw materials with different applications, among which extraction of the essential oil (EO) has gained increasing interest in many fields. The aim of the present study is the evaluation of the yield and the chemical composition of the EO obtained by hydrodistillation from eleven hemp genotypes, cultivated in the same location for two consecutive growing seasons. The composition of the EOs was analyzed by GC–MS, and then subjected to multivariate statistical analysis. Sesquiterpenes represented the main class of compounds in all the EOs, both in their hydrocarbon and oxygenated forms, with relative abundances ranging from 47.1 to 78.5%; the only exception was the Felina 32 sample collected in 2019, in which cannabinoids predominated. Cannabinoids were the second most abundant class of compounds, of which cannabidiol was the main one, with relative abundances between 11.8 and 51.5%. The statistical distribution of the samples, performed on the complete chemical composition of the EOs, evidenced a partition based on the year of cultivation, rather than on the genotype, with the exception of Uso-31. Regarding the extraction yield, a significant variation was evidenced among both the genotypes and the years of cultivation. 相似文献
130.
Xiang Zhu Songhai Chai Chengcheng Tian Pasquale F. Fulvio Kee Sung Han Edward W. Hagaman Gabriel M. Veith Shannon M. Mahurin Suree Brown Honglai Liu Sheng Dai 《Macromolecular rapid communications》2013,34(5):452-459
A porous, nitrogen‐doped carbonaceous free‐standing membrane (TFMT‐550) is prepared by a facile template‐free method using letrozole as an intermediate to a triazole‐functionalized‐triazine framework, followed by carbonization. Such adsorption/diffusion membranes exhibit good separation performance of CO2 over N2 and surpassing the most recent Robeson upper bound. An exceptional ideal CO2/N2 permselectivity of 47.5 was achieved with a good CO2 permeability of 2.40 × 10−13 mol m m−2 s−1 Pa−1. The latter results arise from the presence of micropores, narrow distribution of small mesopores and from the strong dipole–quadrupole interactions between the large quadrupole moment of CO2 molecules and the polar sites associated with N groups (e.g., triazine units) within the framework. 相似文献