In recent years, bismuth-rich Mg
(Sb
Bi
)
(
= 0.5-0.8) compositions have generated significant interest due to their excellent thermoelectric (TE) performance near room temperature, making them ...potential applicants for recovery of low-grade waste heat. The superior performance in these materials is due to its complex electronic band structure (EBS) with presence of multiple near degenerate bands close to the conduction band edge. The position and curvature of these bands strongly depend on the alloy composition, doping amount as well as temperature. Thus, identifying optimal material compositions to get the best TE performance depends on an understanding of the temperature dynamics of EBS and forms the objective of this work. Mg
Sb
Bi
(
= 0.7) is chosen for this study due to its reported high near room temperature performance, and compositions with varying doping concentrations (Te used as dopant) have been synthesized. EBS parameters like effective mass and deformation potential of bands, interband separation and band gap values have been estimated using a recently developed refinement approach. Refinement results indicate that the interband separation between conduction bands to be a function of both temperature and doping concentration. Further, thermal conductivity (κ) was estimated for all of the compositions. Utilizing the EBS and κ information, predictive 3D maps indicating the variation in
(TE figure of merit) with doping concentration and temperature have been generated. The 3D maps reveal an interesting surface topography with a broad peak
region. This observation explains why these materials have high TE performance and are less sensitive to doping inhomogeneities. Our results provide detailed EBS information and fundamental insights on the TE properties of Mg
Sb
Bi
. Further, the proposed technique can be utilized to probe other Mg
(Sb
Bi
)
compositions and TE materials.
In recent years, bismuth-rich Mg3(Sb1–x Bi x )2 (x = 0.5–0.8) compositions have generated significant interest due to their excellent thermoelectric (TE) performance near room temperature, making ...them potential applicants for recovery of low-grade waste heat. The superior performance in these materials is due to its complex electronic band structure (EBS) with presence of multiple near degenerate bands close to the conduction band edge. The position and curvature of these bands strongly depend on the alloy composition, doping amount as well as temperature. Thus, identifying optimal material compositions to get the best TE performance depends on an understanding of the temperature dynamics of EBS and forms the objective of this work. Mg3Sb0.6Bi1.4 (x = 0.7) is chosen for this study due to its reported high near room temperature performance, and compositions with varying doping concentrations (Te used as dopant) have been synthesized. EBS parameters like effective mass and deformation potential of bands, interband separation and band gap values have been estimated using a recently developed refinement approach. Refinement results indicate that the interband separation between conduction bands to be a function of both temperature and doping concentration. Further, thermal conductivity (κ) was estimated for all of the compositions. Utilizing the EBS and κ information, predictive 3D maps indicating the variation in zT (TE figure of merit) with doping concentration and temperature have been generated. The 3D maps reveal an interesting surface topography with a broad peak zT region. This observation explains why these materials have high TE performance and are less sensitive to doping inhomogeneities. Our results provide detailed EBS information and fundamental insights on the TE properties of Mg3Sb0.6Bi1.4. Further, the proposed technique can be utilized to probe other Mg3(Sb1–x Bi x )2 compositions and TE materials.
The diagnosis of Dengue and Chikungunya infections during acute phase is a priority considering emerging pattern and increasing trends of their infections. The present study describes the commercial ...development and validation of RT-PCR test for the simultaneous detection of of DEN and CHIK viral RNA in a single tube from human plasma samples. Multistep one step RT-PCR assay was developed and validated for detection and discrimination of DEN and CHIK along with exogenous internal control. The test was evaluated for commercial use using 3 different lots to determine analytical sensitivity, specificity, precision and stability. The external clinical evaluation was performed at NABL accredited lab with known positive and negative Chikungunya and Dengue specimens and comparator assay method. The findings showed that the test could identify CHIK and DEN viral nucleic acid in clinical samples within 80 min, without any cross-reactivity. The analytical detection limit of the test was 1.56 copies/µl for both. The clinical sensitivity and specificity was ≥ 98% and provide a high-throughput and screen up to 90 samples in a single run. It is available in a freeze-dried format and can be used in both the manual and automated platforms. This unique combo test, PathoDetect™ “CHIK DEN Multiplex PCR Kit” enables simultaneous, sensitive, specific detection of DENV and CHIKV and serves as “ready to use” platform for commercial use. It would aid the differential diagnosis as early as day 1 of the infection and facilitate screen-and-treat approach.
•A RT-PCR based test and automated testing platform for MTB and drug resistance detection in a single run.•Includes all the reagents required to perform sample to result analysis in 2.5 h.•PCR ...components in lyophilized format.•Inclusion of controls for quality check, ensure result integrity and result reliability.•Analytical sensitivity of 25 CFU/ml for MTB detection, 200 CFU/ml for rpoB, inhA and katG genes.•Compatible with respiratory pulmonary and non- pulmonary specimens.•Storage and transport at ambient temperature (15–30 °C).
A real time-polymerase chain reaction-based test in lyophilized form, was developed to simultaneously identify Mycobacterium tuberculosis complex (MTC) by targeting IS6110, rrs as dual markers, as well as mutations causing rifampicin and isoniazid resistance. The test was evaluated for pulmonary and non-pulmonary specimens from sample isolation to PCR analysis. The test demonstrated limit of detection of 25 CFU/mL for MTB, 200 CFU/mL for rpoB and inhA/katG targets with >95 % CI. The specificity for MTC was supported by a comprehensive clinical validation (n = 100). This load-and-go molecular platform, with features of high throughput, long shelf-life, room temperature storage provides simultaneous detection of MTC and its drug-resistant mutations in minimal time. The test named “PathoDetect TM MTB-RIF and INH resistance detection kit” has been approved by Central Drugs Standard Control Organisation, Indian Council of Medical Research and would have implications for tuberculosis elimination programs.
Waste foundry sand (WFS), an industrial waste mainly comprising silicon dioxide was used to generate low-cost and efficient adsorbents for the expulsion of toxic pollutants from water through ...adsorption. The WFS was converted into particles by top–down approach followed by subsequent activation and functionalization. Activated sand particles (ASPs) with –OH groups and amino-functionalized sand particles (AFSPs) with –NH
2
groups were synthesized and fully characterized using FESEM, EDX, ATR-FTIR, XRD, TGA, and BET analyses. The adsorption capacities at experimental conditions for cationic dyes namely methylene blue(MB), malachite green(MG), methyl violet (MV), rhodamine B(Rh B) were 38.16, 26.31, 55.24 and 35.84 mg g
−1
while for anionic dyes namely methyl orange (MO), patent blue VF(PB VF), quinoline yellow(QY), reactive Red 2(RR 2) were 7.28, 4.63, 7.84 and 6.91 mg g
−1
as well as for metal ions namely Cd(II)), Ni(II)), Co(II)), and Cr(VI)were 23.81, 43.06, 17.03 and 3.47 mg g
−1
respectively. The adsorption equilibrium isotherms optimally fit the Langmuir isotherm model, indicating homogeneous surfaces and monolayer adsorption. A pseudo-second-order model showed a strong agreement with the experimental data, thus identifying chemisorption as the rate-limiting step. Additionally, these particles were verified to be reusable for a minimum five adsorption–desorption cycles without loss of efficiency.
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