排序方式: 共有43条查询结果,搜索用时 250 毫秒
21.
Yeow YL Pepperell CJ Sabturani FM Leong YK 《Langmuir : the ACS journal of surfaces and colloids》2008,24(19):10942-10949
A database linking the dimensionless volume of pendant droplets Vpen and the dimensionless volume of the spherical caps at the apex of the droplets Vcap has been constructed from the governing equations of pendant droplet tensiometry. The Bond number Bo that relates surface tension to gravitational body force appears as an independent parameter in this database. Computing Vpen and Vcap from the measured profile of a droplet and making use of the database allow the prevailing Bo to be determined and surface tension to be calculated. This new way of converting measured profiles into surface tension has a number of advantages, such as reliability and simplicity, compared to existing methods. These are demonstrated by applying the new method to a number of measured profile data taken from the literature. 相似文献
22.
Firdaus E. Udwadia 《Nonlinear dynamics》2016,84(3):1135-1145
23.
The effect of Cu/Al molar ratio on the high-temperature adsorption characteristics of CO2 on the mixed oxides of Cu–Al hydrotalcite skeletal structure has been studied by thermogravimetry. The Cu/Al molar ratio
of the hydrotalcites synthesized was varied between 1.0 and 3.0, and the adsorption temperature ranged from ambient to 600 °C.
The hydrotalcite with Cu/Al molar ratio of 2.0 was found to be the most suitable adsorbent for high-temperature CO2 adsorption, in both the capacity and the rate of adsorption. The activation energy values suggested that the physical adsorption
dominates at low temperatures (<400 °C) and the chemisorption dominates at high temperatures (>400 °C). 相似文献
24.
Firdaus ML Norisuye K Sato T Urushihara S Nakagawa Y Umetani S Sohrin Y 《Analytica chimica acta》2007,583(2):296-302
Here, we present the first simultaneous preconcentration and determination of ultratrace (pmol kg−1 level) Zr, Hf, Nb, Ta and W in seawater, both in the form of dissolved and acid-dissolvable species. 8-Hydroxyquinoline (8HQ) bonded covalently to a vinyl polymer resin, TSK-8HQ, was used in a chelating adsorbent column to concentrate the metals. The greatest advantage of this resin is its endurance to 5 M HF, since this is an effective eluent for all five metals. The analytes were successfully concentrated from 250 mL seawater with a 50-fold concentration factor through the column extraction and evaporation. The detection limit was 0.009-0.15 pmol kg−1. The procedure blank determined using ultra pure water as a sample was 0.005-0.37 pmol kg−1. The five metals were quantitatively recovered from seawater with good precision (2-4%). The effect of sample pH, sample flow rate, eluent composition and sample pretreatment were carefully studied. This method was applied to seawater. 相似文献
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26.
Ahmad Firdaus B. Lajis Mahiran Basri Rosfarizan Mohamad Muhajir Hamid Siti Efliza Ashari Nurazwa Ishak Azulia Zookiflie Arbakariya B. Ariff 《Chemical Papers》2013,67(6):573-585
In this paper, enzymatic methods for the synthesis of 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one (kojic acid) esters are reviewed. Important process parameters related to the synthesis of kojic acid esters such as the type of immobilized lipase, solvent, temperature, initial water activity, water content, pH, metal salts, enzyme loading, substrates mole ratio, and acyl donors are highlighted and discussed. The properties of kojic acid esters related to their solubility, stability, cytotoxicity, depigmenting activity, tyrosinase inhibitory, metal-chelating, anti-oxidant, and other biological activities are also highlighted. At present, kojic acid and its esters are widely used in cosmetic and skin health industries as skin whitening agents. The advantages and disadvantages of various kojic acid esters are compared and possible industrial applications of these derivatives are also discussed. 相似文献
27.
This paper presents a direct proof of the recursive formulae for the generalized LM- inverse of a matrix augmented by a column vector. The recursive relations are proved by direct verification of the four conditions of the generalized LM-inverse. Several auxiliary results pertaining to generalized inverses are also provided. 相似文献
28.
Shakir M Azam M Parveen S Khan AU Firdaus F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,71(5):1851-1856
The Schiff base ligand, N,N'-bis-(2-pyridinecarboxaldimine)-1,8-diaminonaphthalene (L), obtained by the condensation of 2-pyridinecarboxaldehyde and 1,8-diaminonaphthalene, has been used to synthesize the mononuclear complexes of the type [MLCl(2)] [M=Co(II), Ni(II), Cu(II) and Zn(II)]. The newly synthesized ligand (L) and its complexes have been characterized on the basis of results of elemental analysis, molar conductance, magnetic susceptibility measurements, Job's method and spectroscopic studies viz., FT-IR, Mass, (1)H and (13)C NMR. The UV-vis and magnetic moment data revealed an octahedral geometry around Co(II), Ni(II) and Cu(II) ions and conductivity data show a non-electrolytic nature of the complexes. Absorption and fluorescence spectroscopic studies support that Cu(II) complex exhibits significant binding to calf thymus DNA. 相似文献
29.
Akmaral Seitkhan Marios Neophytou Mindaugas Kirkus Edy Abou‐Hamad Mohamed Nejib Hedhili Emre Yengel Yuliar Firdaus Hendrik Faber Yuanbao Lin Leonidas Tsetseris Iain McCulloch Thomas D. Anthopoulos 《Advanced functional materials》2019,29(49)
A simple approach that enables a consistent enhancement of the electron extracting properties of the widely used small‐molecule Phen‐NaDPO and its application in organic solar cells (OSCs) is reported. It is shown that addition of minute amounts of the inorganic molecule Sn(SCN)2 into Phen‐NaDPO improves both the electron transport and its film‐forming properties. Use of Phen‐NaDPO:Sn(SCN)2 blend as the electron transport layer (ETL) in binary PM6:IT‐4F OSCs leads to a remarkable increase in the cells' power conversion efficiency (PCE) from 12.6% (Phen‐NaDPO) to 13.5% (Phen‐NaDPO:Sn(SCN)2). Combining the hybrid ETL with the best‐in‐class organic ternary PM6:Y6:PC70BM systems results to a similarly remarkable PCE increase from 14.2% (Phen‐NaDPO) to 15.6% (Phen‐NaDPO:Sn(SCN)2). The consistent PCE enhancement is attributed to reduced trap‐assisted carrier recombination at the bulk‐heterojunction/ETL interface due to the presence of new energy states formed upon chemical interaction of Phen‐NaDPO with Sn(SCN)2. The versatility of this hybrid ETL is further demonstrated with its application in perovskite solar cells for which an increase in the PCE from 16.6% to 18.2% is also demonstrated. 相似文献
30.
Wireless Personal Communications - The current network architecture scene can be a challenge due to the increasing number of user equipment and its diversity. Furthermore, the demand for greater... 相似文献