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131.
Kadir Erol 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(10):629-635
The separation and purification of important biomolecule deoxyribonucleic acid (DNA) molecules are extremely important. The adsorption technique among these methods is highly preferred as the adsorbent cryogels are pretty much used due to large pores and the associated flow channels. In this study, the adsorption of DNA via Co(II) immobilized poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) [poly(HEMA-GMA)] cryogels was performed under varying conditions of pH, interaction time, initial DNA concentration, temperature, and ionic strength. For the characterization of cryogels; swelling test, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), surface area (BET), elemental and ICP-OES analysis were performed. L-lysine amino acid was chosen as Co(II)-chelating agent and the adsorption capacity of cryogels was determined as 33.81 mg DNA/g cryogel. Adsorption of pea DNA was studied under the optimum adsorption conditions and DNA adsorption capacity of cryogels was found as 10.14 mg DNA/g cryogel. The adsorption process was examined via Langmuir and Freundlich isotherm models and the Langmuir adsorption model was determined to be more appropriate for the DNA adsorption onto cryogels. 相似文献
132.
Roscioli JR Hammer NI Johnson MA Diri K Jordan KD 《The Journal of chemical physics》2008,128(10):104314
We report a combined photoelectron and vibrational spectroscopy study of the (H(2)O)(7)(-) cluster anions in order to correlate structural changes with the observed differences in electron binding energies of the various isomers. Photoelectron spectra of the (H(2)O)(7)(-) . Ar(m) clusters are obtained over the range of m=0-10. These spectra reveal the formation of a new isomer (I') for m>5, the electron binding energy of which is about 0.15 eV higher than that of the type I form previously reported to be the highest binding energy species [Coe et al., J. Chem. Phys. 92, 3980 (1990)]. Isomer-selective vibrational predissociation spectra are obtained using both the Ar dependence of the isomer distribution and photochemical depopulation of the more weakly (electron) binding isomers. The likely structures of the isomers at play are identified with the aid of electronic structure calculations, and the electron binding energies, as well as harmonic vibrational spectra, are calculated for 28 low-lying forms for comparison with the experimental results. The HOH bending spectrum of the low binding type II form is dominated by a band that is moderately redshifted relative to the bending origin of the bare water molecule. Calculations trace this feature primarily to the bending vibration localized on a water molecule in which a dangling H atom points toward the electron cloud. Both higher binding forms (I and I') display the characteristic patterns in the bending and OH stretching regions signaling electron attachment primarily to a water molecule in an AA binding site, a persistent motif found in non-isomer-selective spectra of the clusters up to (H(2)O)(50)(-). 相似文献
133.
Kadir Ocalan 《中国物理C(英文版)》2021,45(6):063106-063106-8
This paper presents perturbative QCD predictions of the electron charge asymmetry for inclusive W~±X→e~±v+X production in proton-proton(pp) collisions.Perturbative QCD calculations are performed at nextto-next-to-leading order(NNLO) accuracy using different parton distribution function(PDF) models at 8,13,and 14 TeV center-of-mass energies of CERN LHC pp collisions.NNLO calculations are performed for electrons with transverse momenta above 20 GeV in the forward electron pseudorapidity region 2.0 ≤η_e≤4.25.NNLO predictions are first compared at 8 TeV with the measurements of the LHCb experiment at the LHC for the W~+/W~-cross section ratio and charge asymmetry distributions.The 8 TeV predictions using NNPDF3.1,CT14,and MMHT2014 PDF sets are reported to be in good agreement with the LHCb data for the entire η_e region,justifying the extension of the calculations to 13 and 14 TeV energies.The charge asymmetry predictions at NNLO accuracy are reported in the forward η_e bins at 13 and 14 TeV and compared among NNPDF3.1,CT14,and MMHT2014 PDF sets.Overall,the predicted W~± differential cross-section and charge asymmetry distributions based on different PDF sets are found to be consistent with each other for the entire η_e region.The charge asymmetry distributions are shown to be more sensitive to discriminate among different PDF models in terms of the 14 TeV predictions. 相似文献
134.
Solid polymer electrolytes based on potato starch (PS) and graphene oxide (GO) have been developed in this study. Blending GO with PS has improved the ionic conductivity and mechanical properties of the electrolytes. In this work, series of polymer blend consisting of PS and GO as co-host polymer were prepared using solution cast method. The most amorphous PS-GO blend was obtained using 80 wt% of PS and 20 wt% of GO as recorded by X-ray diffraction (XRD). Incorporation of 40 wt% lithium trifluoromethanesulfonate (LiCF3SO3) into the PS-GO blend increases the conductivity to (1.48 ± 0.35) × 10?5 S cm?1. Further enhancement of conductivity was made using 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]). The highest conductivity at room temperature is obtained for the electrolyte containing 30 wt% of [Bmim][Cl] with conductivity value of (4.8?0 ± 0.69) × 10?4 S cm?1. Analysis of the Fourier transform infrared spectroscopy (FTIR) spectra confirmed the interaction between LiCF3SO3, [Bmim][Cl], and PS-GO blend. The variation of the dielectric constant and modulus studies versus frequency indicates that system of PS-GO-LiCF3SO3-[Bmim][Cl] obeys non-Debye behavior. 相似文献
135.
Nur Amira Md Amin Siti Hamimah Sheikh Abdul Kadir Akmal Hisyam Arshad Norhaslinda Abdul Aziz Nurul Alimah Abdul Nasir Normala Ab Latip 《Molecules (Basel, Switzerland)》2022,27(6)
Vitamin E is known as an essential vitamin, and many studies had demonstrated the importance of vitamin E throughout the reproductive process, such as miscarriage, premature birth, preeclampsia, and intrauterine growth restriction, which could be caused by a lack of vitamin E during pregnancy. Its potent antioxidant properties can counteract the oxidative stress induced by oxygen free radicals and imbalance of oxidative-antioxidant levels, hence it may play a role in maintaining the normal function of the female reproductive system. Despite the fact that vitamin E is acknowledged as the substance needed for reproduction, its beneficial effects on female fertility, gynaecological health, and diseases are still poorly understood and lacking. Therefore, the goal of this paper is to provide a summary of the known roles of vitamin E supplementation in women for gynaecological health and reproductive-related diseases, as well as its future perspective. 相似文献
136.
Tabak Ahmet Sevimli Kadir Kaya Mehmet Çağlar Bülent 《Journal of Thermal Analysis and Calorimetry》2019,138(6):3885-3895
Journal of Thermal Analysis and Calorimetry - The novel activated carbon materials were synthesized by the carbonization and chemical activation of agricultural bio-waste from tea woody stems... 相似文献
137.
N.H. Shamsudin Suhaidi Shafie Mohd Zainal Abidin Ab Kadir Fauzan Ahmad Amir Reza Sadrolhosseini Yusran Sulaiman Abdul Halim Abdullah Siti Amaniah Mohd Chachuli 《Surface and interface analysis : SIA》2022,54(2):109-116
The multiple sizing of silver nanoparticles (AgNPs) were synthesized from the miscible compound of ethylene glycol (EG), polyvinylpyrrolidone (PVP) and silver nitrate (AgNO3) via the solvothermal method. During the synthesis, the PVP-AgNO3 was contemplated as a paramount parameter. Using the simple method of solvothermal, the sizing of AgNPs was easily controlled in accord with the augmentation of PVP-AgNO3 at secured and moderate temperature. In regards to the sizing of AgNPs, the presence of minimum agglomeration, the absorption capability and chemical structures were highlighted through a series of verification includes ultraviolet–visible (UV–Vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) analysis. The effectiveness of the synthesized AgNPs was further investigated and compared with the commercial AgNPs by incorporating the AgNPs into titanium dioxide (TiO2) semiconductor film-based dye-sensitized solar cells (DSSCs). Results signified that the spherical AgNPs with produced sizing within the range of 19.6 to 45.2 nm were greatly impacting by tunable quantities of PVP-AgNO3, which was validated in the forms of linear equations. A larger size promotes a slower nucleation rate that conduces agglomeration. In opposition to this, the smallest size of AgNPs develops a faster formation rate of Ag ions into AgNPs, inducing the deterrent of agglomeration in light of notable particle dispersion. The power conversion efficiency (PCE) contributed by the incorporation of synthesized AgNPs into TiO2 is also 41.2% higher than that of the commercial AgNPs-TiO2. This is because the synthesized AgNPs provides less agglomeration which led to a better surface plasmonic effect towards the nanoparticles. 相似文献
138.
The regio- and stereospecific synthesis of dl-4,5-dibromo-4,5-dideoxy-3,6-O-methyl-chiro-inositol is reported. Bromination of p-benzoquinone followed by reduction of the carbonyl groups with NaBH4 gave the corresponding trans-dibromodiol compound, which was reacted with sodium methoxide to produce dimethoxy conduritol-B. Regiospecific bromination of the alkene moiety furnished the desired chiro-inositol derivative. 相似文献
139.
Shujahadeen B. Aziz Elham M. A. Dannoun Mohamad A. Brza Niyaz M. Sadiq Muaffaq M. Nofal Wrya O. Karim Sameerahl I. Al-Saeedi Mohd F. Z. Kadir 《Molecules (Basel, Switzerland)》2022,27(3)
In this report, the preparation of solid polymer electrolytes (SPEs) is performed from polyvinyl alcohol, methyl cellulose (PVA-MC), and ammonium chloride (NH4Cl) using solution casting methodology for its use in electrical double layer capacitors (EDLCs). The characterizations of the prepared electrolyte are conducted using a variety of techniques, including Fourier transform infrared spectroscopy (FTIR), electrical impedance spectroscopy (EIS), cyclic voltammetry (CV), and linear sweep voltammetry (LSV). The interaction between the polymers and NH4Cl salt are assured via FTIR. EIS confirms the possibility of obtaining a reasonably high conductance of the electrolyte of 1.99 × 10−3 S/cm at room temperature. The dielectric response technique is applied to determine the extent of the ion dissociation of the NH4Cl in the PVA-MC-NH4Cl systems. The appearance of a peak in the imaginary part of the modulus study recognizes the contribution of chain dynamics and ion mobility. Transference number measurement (TNM) is specified and is found to be (tion) = 0.933 for the uppermost conducting sample. This verifies that ions are the predominant charge carriers. From the LSV study, 1.4 V are recorded for the relatively high-conducting sample. The CV curve response is far from the rectangular shape. The maximum specific capacitance of 20.6 F/g is recorded at 10 mV/s. 相似文献
140.
Metin Gençten Koray B. Dönmez Yücel Şahin Kadir Pekmez Ender Suvacı 《Journal of Solid State Electrochemistry》2014,18(9):2469-2479
The gel electrolyte is an important component of the valve-regulated lead-acid (VRLA) batteries. In this study, fumed silica-based gel electrolyte systems were prepared. In this concept, several important parameters controlling the performance of the GEL-VRLA battery, such as the sulfuric acid and fumed silica concentrations, gel formulation, gelling time and rate, and different additives (Na2SO4 and MgSO4), were scientifically investigated. The gel formulations were characterized by cyclic voltammetric and electrochemical impedance spectroscopic methods. The optimum parameters were determined by using the results of anodic peak currents and redox capacities, R s and R ct values. Addition of 6 % (w/w) fumed silica to 30 % (w/w) sulfuric acid, for preparation of gelled electrolyte, increased the battery performance significantly. According to the results of the transmission electron and optic microscope images of the gel electrolytes, the three-dimensional gel structure was prepared successfully. The optimization of sulfuric acid concentration and amount of Na2SO4 and MgSO4 additives were examined for the first time in detail by cyclic voltammetry, electrochemical impedimetry, and battery test. Na2SO4 and MgSO4 additives make a good combination with a gelled-electrolyte system and improve the charge/discharge capacity according to sulfuric acid electrolytes. According to the experimental results, the fumed silica-based gel electrolyte system has a great potential for application in gelled electrolyte VRLA batteries. 相似文献