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741.
In the present work investigations on the effect of stoichiometric variations on the Occurrence and stabilization of quasicrystalline (qc) and related phases have been carried out. Based on the explorations of several Al-deficient and Al-rich versions of the ideal nominal composition i.e. Al65Cu20Cr15, it has been found that the alloy compositions corresponding to Al62Cu23Cr15 (Al-deficient) and Al68Cu17Cr15 (Al-rich) exhibit several structural subtleties. The Al-deficient alloy, has been found to exhibit crystalline bcc and fcc phases with a = 8.90 Å and a = 17.98 Å respectively. In addition to these phases, a new crystalline bcc variant (a = 15.42 Å) originating from the bcc (a = 8.90 Å) phase has been found. Also a curious superstructure of the fcc (a = 17.98 Å) has been observed. The Al-rich alloy typified by Al68Cu17Cr15, on the other hand, does not exhibit any structural variants, instead it shows nearly pure i-phase. 相似文献
742.
Ananya Tiwari Mamta Yadav Devesh Kumar Singh Vellaichamy Ganesan 《Electroanalysis》2023,35(2):e202200106
This work reports an electrochemical sensing framework for nicotine determination based on glassy carbon electrode (GC) immobilized with Fe(bpy)32+ (where bpy is 2,2’-bipyridyl) supported by Nafion and multi-walled carbon nanotubes (Nf-MWCNTs). Fe(bpy)32+ immobilized Nf-MWCNTs modified GC (GC/Nf-MWCNTs/Fe(bpy)32+) manifests stable redox peaks, characteristics of Fe(bpy)32+. The GC/Nf-MWCNTs/Fe(bpy)32+ exhibits effective electrochemical oxidation of nicotine, diminishing the overpotential relative to GC/Nf-MWCNTs. The limit of detection is 0.1 μM (experimentally observed) with two different linear calibration ranges between 0.1 to 600 μM and 600 to 3000 μM. Electrocatalytic responses observed at GC/Nf-MWCNTs/Fe(bpy)32+ indicate superior performance for nicotine determination with acceptable selectivity, stability, and reproducibility. Additionally, the nicotine present in real samples such as beedi and tobacco are also analyzed with satisfactory recovery percentages. 相似文献
743.
Anil Gattani Sanju Mandal M Hira Khan Anand Jain Deepika Ceaser Aditya Mishra S P. Tiwari 《Electroanalysis》2023,35(3):e202200255
Parasitic diseases are among neglected disease of human and animals, especially in tropical and sub tropical regions. In the era of artificial intelligence, the novel biosensing diagnostic platform is needed for an early control measure implementation. This goal can be successfully achieved by onsite application of electrochemical biosensors. They are being developed towards point of care diagnostics; however commercial availability is scanty. The recent developments during last one decade in terms of the electrode surface modification for rapid diagnosis of important emerging/re-emerging parasites is presented. The information would help future improvement in the electrochemical biosensing of parasites. 相似文献
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746.
G. Singh I. Bhaumik S. Ganesamoorthy A. K. Karnal V. S. Tiwari 《Crystal Research and Technology》2007,42(4):378-383
Domain structure and phase transition sequence of 0.91PZN‐0.09PT single crystal, grown from high temperature solution, have been analysed using polarised light microscopy. The domain structure of (001)cub cut single crystal exhibit co‐existence of rhombohedral and tetragonal phases. The sequence and phase transition temperatures have been determined from temperature dependence of birefringence. Birefringence measurements during heating and cooling reveal a first order nature of phase transition between rhombohedral (R3m) and tetragonal (P4mm). The birefringence was measured with accuracy of 10‐3. However, dielectric measurement does not provide any evidence of R3m ‐ P4mm phase transition. It is shown that in‐situ analysis of domain structure and phase transition can be used as non‐destructive analytical tool for determination of local composition and phase transition sequence. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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748.
Deepshikha Yadav Shilpi Verma Jyoti Choudhary Harleen Kaur Pratibha Tiwari Sandeep Singh Pallavi Kushwaha Premshankar K. Dubey Pranjal Chandra Surinder P. Singh 《Electroanalysis》2023,35(4):e202200286
Folic acid (FA) deficiency is associated with several clinical conditions such as megaloblastic anemia, neuropsychiatric, and pregnancy-related syndromes, this makes FA an important metabolite to be monitored. We have fabricated an electrochemical biosensor based on gold nanoparticles decorated molybdenum disulfide nanosheets (AuNPs−MoS2NSs) nanocomposite as a transducer matrix for specific and rapid electrochemical detection of FA. Differential pulse voltammetry (DPV) studies displayed a rapid analytical response of the fabricated AuNPs−MoS2NSs/GCE sensor probe towards FA in a wide concentration range of 0.001–100 μM with a very low detection limit of 0.72±0.03 nM. The selectivity of the fabricated sensor probe has been examined in the presence of interferents such as dopamine, uric acid, ascorbic acid, glucose, and urea. The clinical potential of the fabricated biosensor was established by monitoring FA in human serum samples. The developed AuNPs−MoS2NSs/GCE sensor probe showed high reproducibility and stability, indicating its promise for FA detection in clinical settings. 相似文献
749.