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131.
In situ temperature dependent energy-dispersive structural and magnetic study of electron beam evaporated Fe/Al multilayer sample (MLS) has been investigated. The structural studies show the formation of an intermixed FeAl transition layer of a few nanometers thick at the interface during deposition, which on annealing at 300 °C transforms to B2FeAl intermetallic phase. Magnetization decreases with increase in temperature and drops to minimum above 300 °C due to increase in anti-ferromagnetic interlayer coupling and formation of nonmagnetic FeAl phase at the interface. The Curie temperature (Tc) is found to be 288 °C and is much less than that of bulk bcc Fe.  相似文献   
132.
For a given set M of positive integers, a problem of Motzkin asks for determining the maximal density μ(M) among sets of nonnegative integers in which no two elements differ by an element of M. The problem is completely settled when |M|?2, and some partial results are known for several families of M for |M|?3, including the case where the elements of M are in arithmetic progression. We consider some cases when M either contains an arithmetic progression or is contained in an arithmetic progression.  相似文献   
133.
Commercialization of Li–S in present scenario is obstructed by poor performance of cathode and its compatibility with electrolyte used. Here in this work, in order to improve the electrochemical performance all solid state Li–S battery, solid electrolyte (SE) formed by composition of lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5) combinedly called LPS is used. The modified carbon in the form of graphene oxide (GO) and reduced graphene oxide (rGO) as additive is used to provide better electron conduction pathway. High conductivity of the order 10−4 S cm−1 of prepared LPS overcomes the major drawback of insulating nature of sulfur. The coin cells are fabricated by using above mentioned material as a cathode material, LPS as SE, and lithium foil as anode. The prepared nanocomposites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) to study structural and morphological properties. Energy dispersive X-ray spectroscopy (EDS) images of the cathode surface confirms the uniform spreading of material. The electrochemical performance of coin cell is studied by Galvanostatic charge-discharge plot at 0.1 C to check the compatibility of composite and electrolyte prepared. The cells having additive material GO and rGO with host sulfur show better results as compared to the cell having pristine sulfur.  相似文献   
134.
    
Loop mediated isothermal amplification (LAMP) is a nucleic acid amplification technique performed under isothermal conditions. The output of this amplification technique includes multiple different sizes of deoxyribonucleic acid (DNA) structures which are identified by a banding pattern on gel electrophoresis plots. Although this is a specific amplification technique, the complexity of the primer design and amplification still lead to the issue of obtaining false‐positive results, especially when a positive reading is determined solely by whether there is any banding pattern in the gel electrophoresis plot. Here, we first performed extensive LAMP experiments and evaluated the DNA structures using microchip electrophoresis. We then developed a mathematical model derived from the various components that make up an entire LAMP structure to predict the full LAMP structure size in base pairs. This model can be implemented by users to make predictions for specific, DNA size dependent, banding patterns on their gel electrophoresis plots. Each prediction is specific to the target sequence and primers used and therefore reduces incorrect diagnosis errors through identifying true‐positive and false‐positive results. This model was accurately tested with multiple primer sets in house and was also translatable to different DNA and RNA types in previously published literature. The mathematical model can ultimately be used to reduce false‐positive LAMP diagnosis errors for applications ranging from tuberculosis diagnostics to E. coli to numerous other infectious diseases.  相似文献   
135.
    
In this article, we have studied the bound anionic states of DNA and RNA nucleobases using the newly developed bt-PNO-EOM-CCSD method and extended basis sets. All of the five nucleobases have a single bound anionic state, which is dipole bound in nature. The electron affinity corresponding to the dipole-bound state is found to be extremely sensitive to the used basis set, and a proper agreement with the available experimental data requires a large basis set with a sufficient number of diffuse functions. Electron correlation plays a major role in stabilizing the bound anionic states of nucleobases. No valence-bound anionic states are observed for any of the nucleobases.  相似文献   
136.
    
Benzotrithiophene (BTT) isomers were investigated using density functional theory (DFT) and time‐dependent DFT (TD‐DFT) with the aim to explore their structures, linear optical properties, vertical and adiabatic ionization potentials (IPv and IPa), electron affinities (EAv and EAa), and reorganization energies (λ). The computed bond lengths and bond angles at the B3LYP/6–311+G (d, p) level of theory are in good agreement with experimental crystal structures of the known BTTs. These molecules are planar with zero dihedral angle, making them an ideal backbone for high charge mobility. The UV–visible spectra of BTT isomers are in the range 280–360 nm. All BTT isomers have low hole/electron reorganization energies, which is the main characteristic of good hole/electron transporting materials, and these isomers in turn have potential applications in the field of organic materials.  相似文献   
137.
    
In the present work, comparative studies on two ion‐conducting materials, 1‐butyl‐3‐methylimidazolium chloride (BMIMCl) as ionic liquid (IL) and polymer ionic liquid blend, are reported. For the synthesis of polymer ionic liquid blend system, BMIMCl as ionic liquid, PVDF‐HFP and acetonitrile as a solvent are used. The different polymer ionic liquid blend is prepared by adopting universal solution cast technique and electrolyte sample is optimized mixing IL in the polymer by maintaining ratio 1:4. The impedance plot is observed by LCR Hi‐TESTER. The optimized sample of electrolyte system shows higher ionic conductivity of the order ≈10−3 S cm−1. The Arrhenius behavior is found from the temperature dependence conductivity plot, giving activation energy of Ea ≈ 0.073 eV. The ionic transference number is calculated for IL and optimized polymer ionic liquid blend. Electrical potential window stability is observed for IL and polymer ionic liquid blend. The fabrication of electrochemical double layer capacitors (EDLCs) is done by sandwiching ion conducting materials between two carbon electrodes. The specific capacitance of EDLC cell: AC ||(PVDF‐HFP (20 wt%) + (BMIMCl) (80 wt%)|| AC and AC ||BMIMCl|| AC, gives highest capacitance value ≈116.9 and 96.5 mF cm−2 equivalent to single electrode capacitance 54.57 and 52.6 F g−1, respectively, by cyclic voltammetry studies at 1 mV s−1 scan rate.  相似文献   
138.
    
The Raman and infrared (IR) wavenumbers were computed for the Aurivillius structure ABi4Ti4O15 (ABT) (ACa, Sr, Ba) in an orthorhombic space group (A21am, No. 36, C122v) using normal coordinate analysis. This study aimed to investigate the impact of A-site cations on vibrational phonons. The analysis of zone center phonons primarily involved numerous stretching and bending bonds, serving as force constants. These force constants were utilized to assign the calculated wavenumbers in the examined phase for the first time. The theoretical findings in this paper exhibited a favorable correlation with the wavenumbers reported in the literature. Comparisons of force constants, bond lengths, and wavenumbers were conducted to elucidate A-site cation disordering in these intricate compounds. The outcomes indicated that, in the studied complexes, the Sr atom exhibited an ideal radius for fitting into the structure. The mass of the A-site cations was identified as a factor contributing to tilts in the octahedra. An additional analysis was carried out to assess the impact of A-cations on both the affected equatorial and axial bonds, providing a clearer understanding of the structure. Outer octahedra displayed greater sensitivity to A-site cations compared with inner octahedra. A study of potential energy distribution was also conducted in this work to determine the significance of each force constant in all calculated wavenumbers. It was observed that higher wavenumbers were predominantly influenced by vibrations in oxygen atoms, while lower wavenumbers were mainly affected by A-site cations. Notably, overdamping was observed in the lowest frequency of the BBT compound.  相似文献   
139.
This is the report of the subgroup QCD of Working Group-4 at WHEPP-9. We present the activities that had taken place in the subgroup and report some of the partial results arrived at following the discussion at the working group meetings.  相似文献   
140.
Mössbauer spectroscopic studies of two sedimentary layers from Petriccio section in Gubbio formation are presented. It is found that these layers have almost the same iron phases nanophase hematite and phyllosilicate and with the same compositions as those in the Cretaceous-Tertiary Boundary (KTB) in Petriccio. The two layers also show enhancement in the siderophile elements such as Cr, Ni, Fe, Ca etc. to that found in the KTB layer. The two layers are well separated from the KTB layer, 128 and 149 cm below this layer, and show no enhancement of iridium. From the data it is suggested that the two layers also represent some kind of impact by extraterrestrial (ET) bolides.  相似文献   
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