The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is a serious pest of stored products and is the only stored product insect pest that triggers a quarantine response when it ...is found in the United States. The larvae of T. granarium feed on a wide range of dry food products of plant and animal origin, including cereals, dried fish, and museum specimens. In this study, we evaluated the residual efficacy of two pyrethroid insecticides, deltamethrin and cyfluthrin, applied on concrete, wood, painted wood, vinyl flooring tile, and metal surfaces using small and large T. granarium larvae. Residual efficacy of two insect growth regulators (IGRs), methoprene and pyriproxyfen was also evaluated on concrete, metal, and wood surfaces. In both studies, larvae were exposed with provision of a food source on the treated surfaces and residual assays were conducted at 0 months (1 d), 1, 2, and 3 months post treatment. In general, both of the pyrethroids provided a high level of control of T. granarium larvae, though small larvae were much more susceptible than large larvae. The IGRs were comparatively less effective, with more larval survival and adult emergence of exposed larvae compared with the pyrethroids. Residues of the pyrethroids and IGRs were most persistent on the metal surface. Results can be used to help to control and eradicate infestations of T. granarium when they are detected in the United States.
The structural, mechanical, electronic, optical and piezoelectric properties of Na
2
SiO
3
are studied under varying compressive unidirectional pressure (0-50 GPa with a difference of 10 GPa) using ...density functional theory (DFT). The calculated structural properties agree well with previously reported results. At 12 GPa, our calculation shows a structural phase transition from orthorhombic
Cmc
2
1
to triclinic
P
1. The mechanical profile of Na
2
SiO
3
structures under different compressive unidirectional pressures are analysed by calculating the elastic moduli, Poisson's ratio and eigenvalues of stiffness matrix. Our study shows the mechanical stability of the system up to a pressure of 40 GPa. Herein, we have obtained an indirect band gap of 2.97 eV at 0 GPa. Between 0-50 GPa, the band gaps are within the range 2.62 to 3.46 eV. The system in our study possesses a wide band gap and high optical absorption in the UV-Vis range of electromagnetic radiation. The calculated static refractive indices
η
x
,
y
,
z
(0) are close to unity suggesting its transparency. For piezoelectric properties, we have reported the total Cartesian polarization. Our calculations have revealed that Na
2
SiO
3
is a promising candidate for optoelectronic devices while its application in ferroelectric and piezoelectric devices could be improved with further research.
Structural phase transitionoccurs from space group
Cmc
2
1
to C11 at 12 GPA under compressive unidirectional pressure in Na
2
SiO
3
.
Marijuana legalization and disability claiming Maclean, Johanna Catherine; Ghimire, Keshar M.; Nicholas, Lauren Hersch
Health economics,
February 2021, Letnik:
30, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We study the effect of recent legalization of recreational marijuana use laws (RMLs) in the United States on new applications and allowances for Social Security Disability Insurance and Supplemental ...Security Income over the period 2001–2019. We combine administrative caseload data from the Social Security Administration with state policy changes using two‐way fixed‐effects methods. We find that RML adoption increases applications for both benefits. However, there is no change in allowances post‐RML. We provide suggestive evidence that the observed changes in applications post‐RML are driven by increases in marijuana misuse and selective migration, and decreases in unemployment.
A new aurophilically-bonded cyclic trinuclear gold(I) complex, trisμ2-(1-ethylimidazolato-N3,C2)gold(I) (Au3(EtIm)3, 1), has been synthesized and characterized by temperature-dependent ...crystallographic and photophysical investigations. The crystal packing of 1 reveals two independent molecules in the unit cell, signifying two distinct pairs of dimer-of-trimer units convened by pairwise intermolecular Au···Au interactions of 3.0662(3) and 3.1407(3) Å at 100 K, representing the shortest pairwise intermolecular aurophilic interactions among all cyclic trimetallic gold(I) complexes to date. Remarkably, crystals of 1 exhibit gigantic photoluminescence thermochromism of 10164 cm–1from violet to red!attributed to internal conversion between a higher-energy (T2 → S0; λmax ∼409 nm) and lower-energy (T1 → S0; λmax ∼700 nm) phosphorescent band below and above 200 K, respectively, likely representing an excited-state phase change.
We report on the expected sensitivity of dedicated scintillator-based detectors at the LHC for elementary particles with charges much smaller than the electron charge. The dataset provided by a ...prototype scintillator-based detector is used to characterize the performance of the detector and provide an accurate background projection. Detector designs, including a novel slab detector configuration, are considered for the data taking period of the LHC to start in 2022 (Run 3) and for the high luminosity LHC. With the Run 3 dataset, the existence of new particles with masses between 10 MeV and 45 GeV could be excluded at 95% confidence level for charges between 0.003 e and 0.3 e, depending on their mass. With the high luminosity LHC dataset, the expected limits would reach between 10 MeV and 80 GeV for charges between 0.0018 e and 0.3 e, depending on their mass.
A density functional theory (DFT) approach employing generalized gradient approximation (GGA) and the modified Becke Johnson (TB-mBJ) potential has been used to study the electronic and ...thermoelectric (TE) properties of Zr
x
Hf
1−
x
−
y
Ta
y
NiSn. The presence of an indirect band gap at
E
F
in the parent compound predicts this material to be a small band gap insulator. The substitution of Ta atoms at the Hf site increases the density of states (DOS) at
E
F
which facilitates charge carrier mobility. The influence of Ta content increases the Seebeck coefficient and electrical conductivity, and suppresses the thermal conductivity; as a result the figure of merit ZT is enhanced. We report an increment in ZT value of 36% over the undoped system. The theoretical data were compared with the experimental results.
A density functional theory (DFT) approach employing generalized gradient approximation (GGA) and the modified Becke Johnson (TB-mBJ) potential has been used to study the electronic and thermoelectric (TE) properties of Zr
x
Hf
1−
x
−
y
Ta
y
NiSn.
The present study investigates the influence of Cu2+ and La3+-Cu2+ doping on the magnetic properties of Sr1−xLaxFe12−xCuxO19 (x = 0.0–0.5) hexaferrite (SrM) compounds. The samples were prepared via ...facile autocombustion technique followed by sintering. X-ray powder diffraction patterns show the formation of the pure phase of M-type hexaferrite for all x. Invariance in lattice parameters was observed with only Cu2+ substitution while lattice contraction along c-axis was observed with co-doping La3+-Cu2+ in SrM. The magnetic property of these compounds is explained based on Cu2+ occupancy in the absence and presence of La3+ in SrM magnetoplumbite structure. The Cu2+ doped SrFe12−xCuxO19 sample showed a monotonic decrease in Ms value while La3+-Cu2+ showed a noticeable increase in Ms value with x. Furthermore, while coercivity of Cu2+ doped SrM reduced with x, the coercivity of La3+-Cu2+ doped SrM showed a marked 12% increase in coercivity at x = 0.1 (Hc = 4391 Oe) from that of x = 0.0 (3918 Oe). Interestingly, Cu2+ doped SrM displayed invariance in Tc ∼ 458.6 °C with x, while La3+-Cu2+ doping reduced Tc by 5% from its x = 0 (Tc = 451.9 °C) to 429.6 °C. The room temperature Mossbauer spectral analysis confirmed a Cu2+ preference for the 12k site and its occupancy is observed to be influenced by the presence of La3+ ion at the Sr2+ site.
Interconnected hollow-structured carbon was successfully prepared from a readily available bio-waste precursor (orange peel) by pyrolysis and chemical activation (using KOH), and demonstrated its ...potential as a high-performing electrode material for energy storage. The surface area and pore size of carbon were controlled by varying the precursor carbon to KOH mass ratio. The specific surface area significantly increased with the increasing amount of KOH, reaching a specific surface area of 2521 m2/g for a 1:3 mass ratio of precursor carbon/KOH. However, a 1:1 mass ratio of precursor carbon/KOH displayed the optimum charge storage capacitance of 407 F/g, owing to the ideal combination of micro- and mesopores and a higher degree of graphitization. The capacitive performance varied with the electrolyte employed. The orange-peel-derived electrode in KOH electrolyte displayed the maximum capacitance and optimum rate capability. The orange-peel-derived electrode maintained above 100% capacitance retention during 5000 cyclic tests and identical charge storage over different bending status. The fabricated supercapacitor device delivered high energy density (100.4 µWh/cm2) and power density (6.87 mW/cm2), along with improved performance at elevated temperatures. Our study demonstrates that bio-waste can be easily converted into a high-performance and efficient energy storage device by employing a carefully architected electrode–electrolyte system.
Water electrolysis is one of the greenest ways to generate clean energy. However, it is critical to develop durable and cost-effective electrocatalysts using earth-abundant materials for overall ...water splitting. Here we report, a facile method to fabricate N-doped cotton cloth as an electrocatalyst. The N-doped cotton cloth showed outstanding performance as an electrocatalyst for overall water splitting. For oxygen evolution reaction (OER), N-doped cotton cloth requires a low overpotential of 351 mV to deliver 10 mA/cm2 of current density with a Tafel slope of 88 mV/dec. On the other hand, it requires 233 mV to achieve a current density of 10 mA/cm2 for hydrogen evolution reaction (HER) with a Tafel slope of 135 mV/dec. Furthermore, the electrocatalyst showed outstanding electrocatalytic stability and flexibility. The observed overpotential and stability are among the best for the metal-free electrocatalyst. Such a binder-free approach for fabrication of high performance, durable and flexible bi-functional (HER and OER) electrocatalyst could be a promising way to generate green energy from water.
The N-doped cotton cloth was used as an electrocatalyst for overall water splitting. The electrocatalyst showed outstanding electrocatalytic stability and flexibility with relatively low overpotential. The observed overpotential and stability are among the best for the metal-free electrocatalyst (PSU stands for Pittsburg State University). Display omitted
•A facile method was used to fabricate N-doped cotton cloth as an electrocatalyst.•N-doped cotton cloth requires a low overpotential of 351 mV to deliver 10 mA/cm2.•N-doped cotton cloth showed a Tafel slope of 88 mV/dec for OER.•Electrocatalyst requires 233 mV for HER with a Tafel slope of 135 mV/dec.•The electrocatalyst showed outstanding electrocatalytic stability and flexibility.
We report a comprehensive experimental investigation on the magnetic anisotropy in bulk single crystals of Cr2Ge2Te6, a quasi-two-dimensional ferromagnet belonging to the family of magnetic layered ...transition metal trichalcogenides that have recently attracted a great deal of interest with regard to the fundamental and applied aspects of two-dimensional magnetism. For this purpose electron spin resonance (ESR) and ferromagnetic resonance (FMR) measurements have been carried out over a wide frequency and temperature range. A gradual change in the angular dependence of the ESR linewidth at temperatures above the ferromagnetic transition temperature Tc reveals the development of two-dimensional spin correlations in the vicinity of Tc thereby proving the intrinsically low-dimensional character of spin dynamics in Cr2Ge2Te6. Angular and frequency dependent measurements in the ferromagnetic phase clearly show an easy-axis-type anisotropy of this compound. Furthermore, these experiments are compared with simulations based on a phenomenological approach, which takes into account results of static magnetization measurements as well as high temperature g factors obtained from ESR spectroscopy in the paramagnetic phase. As a result the determined magnetocrystalline anisotropy energy density (MAE) KU is (0.48±0.02)×106 erg/cm3. This analysis is complemented by density functional calculations which yield the experimental MAE value for a particular value of the electronic correlation strength U. The analysis of the electronic structure reveals that the low-lying conduction band carries almost completely spin-polarized, quasihomogeneous, two-dimensional states.
PDF
