Boosting proton reduction via isolated Cu atoms in Bi lattice for efficient electroreduction of CO2 to formate

Current Bi-based catalysts suffer from low current density for electroreduction of CO2 to formate due to the high energy barrier of H+ reduction to *H on Bi sites. Here we report a unique BiCu single-atom alloy catalyst (SAAC) that can deliver a ultrahigh formate partial current density (jformate) of 434 mA cm–2, the highest among the reported Bi-based electrocatalysts to date, with a formate Faradaic efficiency (FEformate) of 96.5% at –0.55 V (vs. RHE) in a flow cell, while BiCu alloy catalyst containing Cu nanoclusters can only deliver a jformate of 48.5 mA cm–2 with a FEformate of 37.3% under an identical condition. Mechanism investigations reveal that the isolated single-atom Cu in BiCu SAAC can dramatically reduce the energy barrier of H+ reduction to *H on Cu site for boosting the reduction of CO2 to formate. Our work provides a new strategy for engineering unfavourable energy barrier of electrocatalysts to promote CO2 reduction.

Theorizing Probability Distribution in Applied Statistics

This paper investigates into theoretical knowledge on probability distribution and the application of binomial, poisson and normal distribution. Binomial distribution is widely used discrete random variable when the trails are repeated under identical condition for fixed number of times and when there are only two possible outcomes whereas poisson distribution is for discrete random variable for which the probability of occurrence of an event is small and the total number of possible cases is very large and normal distribution is limiting form of binomial distribution and used when the number of cases is infinitely large and probabilities of success and failure is almost equal.

Neuropsychiatric Manifestations of Acute Intermittent Porphyria – A Diagnostic Dilemma

Porphyrias are a group of inherited or acquired disorders of certain enzymes in the heme bio-synthetic pathway (also called porphyrin pathway). They are broadly classified as acute (hepatic) porphyrias and cutaneous (erythropoietic) porphyrias, based on the site of the overproduction and accumulation of the porphyrins or their chemical precursors. They manifest with either neuropsychiatric complications or skin problems or occasionally both. A clinically induced and histologically identical condition is called pseudo porphyria which is characterized by normal serum and urine porphyrin levels.

A Study on the Effect of Storage of Betel Leaves at Ambient Temperature

A research study was conducted for studying the storage of Madras and Kolkata varieties of betel leaves under ambient temperature with different diffusion storage systems were observed for different treatments. In the treatment T1, the concentration of oxygen, O2 reduced to a minimum of 14.27 per cent and carbon dioxide, CO2 concentration increased to 4.80 per cent on the 14th day of storage in ambient condition (28°C). It was also reported that by the 14th day, betel leaves stored at ambient condition maintained satisfactory quality in the entire diffusion channel chambers. For the Kolkatta leaves the treatment T2, the concentration of O2 was reduced to 12.0 per cent and CO2 concentration increased to 7.87 per cent on the 18th day of storage. Compared to other treatments, the O2 concentration was found to be very low and CO2 concentration was high on the 18th day of storage in T2 diffusion channel. Similarly, on the 18th day, betel leaves stored at ambient condition maintained satisfactory quality in all the treatments. Hence, it is clear that from this present study, different varieties of betel leaves will have different rates of respiration for a particular size of the diffusion channel and temperature. In other words, varietal variation occurs concerning respiration rate under identical condition.

COMPARATIVE STUDY OF HELIUM BUBBLE FORMATION IN Cr-Fe-Ni-Mn HIGH-ENTROPY ALLOY AND 18Cr10NiTi STEEL AFTER IRRADIATION AND POST-IRRADIATION ANNEALING

High entropy alloys (HEAs) are considered for applications in nuclear reactors due to their promising mechanical properties, corrosion and radiation resistance. In order to understand the irradiation effects in HEAs and to demonstrate their potential advantages over conventional austenitic stainless steels, we performed helium ion irradiation experiments with 20Cr-40Fe-20Ni-20Mn high-entropy alloy and 18Cr10NiTi steel under an identical condition. Both alloys have been irradiated to a dose of 4.8 displacement per atom (dpa) and a helium concentration of 11.7 at.% at room temperature. After subsequent annealing at 500 °C the microstructure evolution of irradiated materials was examined. The irradiation promotes the formation of a high density of bubbles in HEA and steel. Comparison of parameters of helium porosity in these materials has been done.

Fabrication and Evaluation of a Novel Non-Invasive Stretchable and Wearable Respiratory Rate Sensor Based on Silver Nanoparticles Using Inkjet Printing Technology

The respiration rate (RR) is a key vital sign that links to adverse clinical outcomes and has various important uses. However, RR signals have been neglected in many clinical practices for several reasons and it is still difficult to develop low-cost RR sensors for accurate, automated, and continuous measurement. This study aims to fabricate, develop and evaluate a novel stretchable and wearable RR sensor that is low-cost and easy to use. The sensor is fabricated using the soft lithography technique of polydimethylsiloxane substrates (PDMS) for the stretchable sensor body and inkjet printing technology for creating the conductive circuit by depositing the silver nanoparticles on top of the PDMS substrates. The inkjet-printed (IJP) PDMS-based sensor was developed to detect the inductance fluctuations caused by respiratory volumetric changes. The output signal was processed in a Wheatstone bridge circuit to derive the RR. Six different patterns for a IJP PDMS-based sensor were carefully designed and tested. Their sustainability (maximum strain during measurement) and durability (the ability to go bear axial cyclic strains) were investigated and compared on an automated mechanical stretcher. Their repeatability (output of the sensor in repeated tests under identical condition) and reproducibility (output of different sensors with the same design under identical condition) were investigated using a respiratory simulator. The selected optimal design pattern from the simulator evaluation was used in the fabrication of the IJP PDMS-based sensor where the accuracy was inspected by attaching it to 37 healthy human subjects (aged between 19 and 34 years, seven females) and compared with the reference values from e-Health nasal sensor. Only one design survived the inspection procedures where design #6 (array consists of two horseshoe lines) indicated the best sustainability and durability, and went through the repeatability and reproducibility tests. Based on the best pattern, the developed sensor accurately measured the simulated RR with an error rate of 0.46 ± 0.66 beats per minute (BPM, mean ± SD). On human subjects, the IJP PDMS-based sensor and the reference e-Health sensor showed the same RR value, without any observable differences. The performance of the sensor was accurate with no apparent error compared with the reference sensor. Considering its low cost, good mechanical property, simplicity, and accuracy, the IJP PDMS-based sensor is a promising technique for continuous and wearable RR monitoring, especially under low-resource conditions.

Experimental comparison of CuAl10Fe3 journal bearings sliding against two different coatings

Purpose The purpose of this paper is to study the frictional behaviors of CuAl10Fe3 journal bearings sliding against chromium electroplated 42CrMo shafts and diamond-like carbon-coated 42CrMo shafts, respectively, under two different conditions and to compare the two kinds of friction pairs. Design/methodology/approach All journal bearing samples underwent 24 h running-in and repeatability verification. Then, the journal bearing friction experiments were carried out under two different conditions. After testing, the torques, friction coefficients, power consumptions and other parameters were obtained. Findings The pair of CuAl10Fe3 journal bearing and diamond-like carbon–coated shaft could drive greater load to start up than the pair of CuAl10Fe3 journal bearing and chromium electroplated 42CrMo shaft, but it had greater power consumption during the steady running period under the identical condition. With the changing of specific pressure or rotational speed, the friction coefficients had different variations. The frictional oscillations appeared at 32 rotations per minute under heavy loads for both kinds of pairs, the oscillation frequencies were equal to rotational frequency of the test shaft and the oscillation amplitude for diamond-like carbon coating was much greater. Originality/value These results have guiding significance for practical industrial applications.

Drag and Lift Characteristics of a Novel Elliptical-Bladed Savonius Rotor With Vent Augmenters

Savonius rotor, a class of drag-driven vertical axis wind turbine, has been extensively investigated mainly to calculate the torque and power coefficients (CT and CP) by various investigators. Hitherto, studies related to lift and drag characteristics are very few and have mainly been restricted to a semicircular-bladed rotor. A deeper investigation into the drag and lift coefficients (CD and CL) can result in the better design of rotor blades leading to an increment in CT and CP. In view of this, in the present investigation, CD and CL of an elliptical-bladed rotor with vent augmenters have been studied numerically. Initially, two-dimensional (2D) unsteady simulations using an ansys fluent solver is carried out to estimate the instantaneous CD and CL. The shear stress transport (SST) k–ω turbulence model is selected to solve the Reynolds averaged Navier Stokes (RANS) equations. Finally, three-dimensional (3D) unsteady simulations are carried out for the vented elliptical-bladed rotor. The unsteady simulations are performed for the nonvented elliptical- and semicircular-bladed rotors at the identical condition in order to have a direct comparison. From the unsteady simulations, the average CD for the vented elliptical profile is found to be 1.45; whereas, the average CD for the nonvented elliptical and semicircular profiles is found to be 1.43 and 1.35, respectively.

Hybrid system solar collectors - heat pumps for domestic water heating

This paper deals with the use of solar energy, heat pumps, and solar system-heat pump combinations for domestic water heating. The testing of solar tiles, flat plate collectors as an autonomous system, as well as flat plate collector-heat pump and solar tile-heat pump combinations, are presented. Black-coloured water absorbs solar radiation flows through solar tiles made of transparent polymethyl methacrylate (CH2C(CH3)COOCH3). At the same time, solar tiles are used as a roof covering and as a solar radiation collector. Hot water from solar tiles or a flat plate collector is directed to the heat pump, which increases the temperature of water entering the boiler heating coil. The heat of water heated in solar tiles or in flat plate collectors serves as a source of energy for the heat pump. Since the goal was realistically evaluate the efficiency of solar tiles in comparison with the flat plate collector, extensive measurements of both systems under identical condition were carried out. The experiments were carried out in rainy, cloudy, and clear weather.

Paternal hyperglycemia in rats exacerbates the development of obesity in offspring

Parental history with obesity or diabetes will increase the risk for developing metabolic diseases in offspring. However, literatures as to transgenerational inheritance of metabolic dysfunctions through male lineage are relatively scarce. In the current study, we aimed to evaluate influences of paternal hyperglycemia on metabolic phenotypes in offspring. Male SD rats were i.p. injected with streptozotocin (STZ) or citrate buffer (CB, as control). STZ-injected rats with glucose levels higher than 16.7 mM were selected to breed with normal female rats. Offspring from STZ or CB treated fathers (STZ-O and CB-O) were maintained in the identical condition. We monitored body weight and food intake, and tests of glucose and insulin tolerance (GTTs and ITTs), fasting–refeeding and cold exposure were performed. Expression of factors involved in hypothalamic feeding and brown adipose tissue (BAT) thermogenic activity was performed by real-time PCR and Western blot. Adult STZ-O were heavier than CB-O. Impairment of GTTs was observed in STZ-O compared with CB-O at 22 and 32 weeks of age; ITTs results showed decreased insulin sensitivity in STZ-O. Daily food intake and accumulated food intake during 12-h refeeding after fasting were significantly higher in STZ-O. UCP1 levels were downregulated in BAT from STZ-O at room temperature and cold exposure. Finally, STZ-O rats showed suppressed leptin signaling in the hypothalamus as evidenced by upregulated SOCS3, reduced phosphorylation of STAT3, impaired processing POMC and decreased α-MSH production. Our study revealed that paternal hyperglycemia predisposes offspring to developing obesity, which is possibly associated with impaired hypothalamic leptin signaling.