Experimental Run Research Articles

All-on-Chip Concurrent Measurements of the Static Magnetization and of the Electron Spin Resonance with Microcantilevers

A large variety of the samples of novel magnetic materials, which are of high interest due to their exotic properties, are only available in very small sizes. In some cases, it is not possible to synthesize large single crystals; in other cases, the small size itself is the key prerequisite to manifest a specifically interesting property of the material. The smallness of a sample rises a problem of the detection of the static magnetic response and of the electron spin resonance (ESR) signal. To overcome this problem, we propose to use a cantilever-based (torque-detected) setup with the capability of a simultaneous measurement of ESR and static magnetization. This setup offers a high sensitivity and the ability to acquire along with the ESR signal the components of the magnetization tensor in a single experimental run. Here, we present the working principle of this setup, as well as the estimate of its sensitivity from the measurements on the standard Co Tutton salt sample.

Testing how different levels of entanglement affect predictability in practical setups

The generation of series of random numbers is an important and difficult problem. Appropriate measurements on entangled states have been proposed as the definitive solution. In principle, this solution requires reaching the challenging “loophole-free” condition, which is unattainable in a practical situation nowadays. Yet, it is intuitive that randomness should gradually deteriorate as the setup deviates from that ideal condition. In order to test whether this trend exists or not, we prepare biphotons with three different levels of entanglement: moderately entangled ( $$S = 2.67$$ ), marginally entangled ( $$S = 2.06$$ ), and non-entangled ( $$S = 1.42$$ ) in a setup that mimics a practical situation. The indicators of randomness we use here are: a battery of standard statistical tests, Hurst exponent, an evaluator of Kolmogorov complexity, Takens’ dimension of embedding, and augmented Dickey–Fuller and Kwiatkowski–Phillips–Schmidt–Shin to check stationarity. A nonparametrical statistical ANOVA (Kruskal–Wallis) analysis reveals a strong influence of the level of entanglement with randomness when measured with Kolmogorov complexity in three time series with P-values and strength factor $$\epsilon ^2$$ : $$P = 0.0015$$ , $$\epsilon ^2 = 0.28$$ ; $$P = 4.5\times 10^{-4}$$ , $$\epsilon ^2 = 0.67$$ and $$P = 5.6\times 10^{-4}$$ , $$\epsilon ^2 = 0.16$$ . The setup is pulsed with time stamping, what allows generate different series applying different methods with the same data, even after the experimental run has ended, and to compare their raw randomness. It also allows the stroboscopic reconstruction of time variation of entanglement.

The Effects of Prize Structures on Innovative Performance

Successful innovation is essential for the survival and growth of organizations, but how best to incentivize innovation is poorly understood. We compare how two common incentive schemes affect innovative performance in a field experiment run in partnership with a large life sciences company. We find that a winner-takes-all compensation scheme generates significantly more novel innovation relative to a compensation scheme that offers the same total compensation but shares it across the ten best innovations. Moreover, the winner-takes-all scheme does not reduce innovative output on average and, among teams of innovators, generates more output than the less risky prize structure.

Deep learning early stopping for non-degenerate ghost imaging

Quantum ghost imaging offers many advantages over classical imaging, including the ability to probe an object with one wavelength and record the image with another (non-degenerate ghost imaging), but suffers from slow image reconstruction due to sparsity and probabilistic arrival positions of photons. Here, we propose a two-step deep learning approach to establish an optimal early stopping point based on object recognition, even for sparsely filled images. In step one we enhance the reconstructed image after every measurement by a deep convolutional auto-encoder, followed by step two in which a classifier is used to recognise the image. We test this approach on a non-degenerate ghost imaging setup while varying physical parameters such as the mask type and resolution. We achieved a fivefold decrease in image acquisition time at a recognition confidence of 75%. The significant reduction in experimental running time is an important step towards real-time ghost imaging, as well as object recognition with few photons, e.g., in the detection of light sensitive structures.

New Cage-Like Cerium Trihydride Stabilized at Ambient Conditions

New Cage-Like Cerium Trihydride Stabilized at Ambient Conditions

Measurement of the Curie temperature based on temperature dependent thermal properties

A temperature gradient evaluation method for swift determination of the Curie temperature TC based on thermal conductivity and thermal diffusivity as functions of temperature is presented. In an imposed one-dimensional temperature gradient, temperature profiles along the axis of a cylindrical sample are recorded in steady-state and transient states using a photon detector. Transient temperature profiles are evaluated by an inverse numerical method, yielding the temperature dependent thermal diffusivity with a distinct change in slope at TC. The slope of the steady-state temperature profile adjusts according to the local thermal conductivity and changes abruptly at TC. The high-resolution determination of the temperature dependent thermal properties allows the identification of TC by two independent evaluations during a single experimental run, solely relying on data of thermal conductivity and thermal diffusivity. The obtained TC excellently agrees with literature values gained by conventional methods.

Chip Morphological Behaviour During Machining Of Ti-6Al-4V Using Refrigerated Soluble Oil

Chips formed during machining are a vital instrument for the assessment both of machinability of material and the effectiveness of the machining method adopted. Various approaches have been proposed by researchers to make machining Ti-6Al-4V easier, ranging from reduction of cutting speed and feed rate to the use of coolant during machining. In this study, investigatation of the effect of refrigerated soluble oil on machinability of Ti-6Al-4V via monitoring of the chips formed during the various machining processes was carried out. The chips formed for various machining conditions were collected using a designed chip receptor medium and was analyzed using a metallographic microscope with an attached stylus. The experiment was planned using central composite designs (CCD) of the Response Surface Methodology (RSM) resulting in a 20 experimental run plan for dry and wet machining. Machining factors considered were cutting speed, feed rate, depth of cut and coolant temperature with corresponding values 40-120 m/min, 0.05-0.20 mm/rev, 0.2-1.0 mm and 5-11°C respectively. Responses monitored chip thickness, tooth profile and peak height. The effect of various factors on responses were discussed. Basically, results show that chip diameter increased with an increase in cutting speed. However, the sawtooth profile on chip reduced with an increase in cutting speed. It was therefore concluded that coolant temperature has an effect on chip morphology during machining of Ti-6Al-4V using refrigerated coolant.

Simultaneous proteoglycans and hypoxia mapping of chondrosarcoma environment by frequency selective CEST MRI

To evaluate the relevance of CEST frequency selectivity in simultaneous in vivo imaging of both of chondrosarcoma's phenotypic features, that are, its high proteoglycan concentration and its hypoxic core. Swarm rat chondrosarcomas were implanted subcutaneously in NMRI nude mice. When tumors were measurable (12-16 days postoperative), mice were submitted to GAG, guanidyl, and APT CEST imaging. Proteoglycans and hypoxia were assessed in parallel by nuclear imaging exploiting 99m Tc-NTP 15-5 and 18 F-FMISO, respectively. Data were completed by ex vivo analysis of proteoglycans (histology and biochemical assay) and hypoxia (immunofluorescence). Quantitative analysis of GAG CEST evidenced a significantly higher signal for tumor tissues than for muscles. These results were in agreement with nuclear imaging and ex vivo data. For imaging tumoral pH in vivo, the CEST ratio of APT/guanidyl was studied. This highlighted an important heterogeneity inside the tumor. The hypoxic status was confirmed by 18 F-FMISO PET imaging and ex vivo immunofluorescence. CEST MRI simultaneously imaged both chondrosarcoma properties during a single experimental run and without the injection of any contrast agent. Both MR and nuclear imaging as well as ex vivo data were in agreement and showed that this chondrosarcoma animal model was rich in proteoglycans. However, even if tumors were lightly hypoxic at the stage studied, acidic areas were highlighted and mapped inside the tumor.

Removal of Trace Metal Impurities from Pretreated Phosphoric Acid by Foam Fractionation

AbstractDemands for phosphoric acid are growing rapidly in various industries. This has highlighted the importance of optimizing its production and purification methods. Phosphoric acid can be produced by a wet process. However, due to the presence of many organic and inorganic impurities in the wet product, purification of the resulting product is a major concern in this industry. Removal of trace metal impurities (such as magnesium, cadmium, chromium, zinc, etc.) from produced phosphoric acid in a wet process was investigated by foam fractionation in a semi‐batch setup using sodium dodecyl sulfate (SDS) as the surfactant. Effects of inlet air velocity, surfactant concentration, and surfactant selectivity were investigated. The optimum air velocity and surfactant concentration were obtained as 0.020 cm/min and 0.7 g/L, respectively. At the optimum condition, the total removal efficiency and enrichment factor reached were 70.2% and 4.39, respectively, while the acid loss was 8.3%. The total metal removal efficiency was increased to 95.3% in a two‐stage experimental run.

Unified chromatography – Mass spectrometry as a versatile tool for determination of food dyes

Unified chromatography with mass spectrometric detection was assessed for determination of food dyes. Nineteen substances representing azo, triphenylmethane, xanthone, indigoid, quinoline and polyene classes covering an unprecedented range from nonpolar β-Carotene (logD 13.6) to ionic Tartrazine (logD −7.5) were analyzed simultaneously. The dyes were separated in a single experimental run by an 18-min gradient elution from 98% CO2 to 100% aqueous-methanolic modifier on a diol column. Isomeric substances were resolved, and Isatin Sulfonic acid was detected as a degradation product of Indigo Carmine. Mobile phase properties reproducibly changed from supercritical to liquid state ensuring stable retention times (inter-day RSD<0.5%). Quantitative analysis of sports drinks after straightforward 10- or 25-fold dilution with dimethyl sulfoxide confirmed the method applicability to real-life samples. Sufficient limits of detection (typically 0.025 mg L−1 in processed samples, equivalent to 0.25 mg L−1 in drink) and a wide linear range (typically 0.5–50 mg L−1 or 1.3–125 mg L−1 in drink for 10× or 25× dilution, respectively) were demonstrated during validation. A comparison of method performance with competitive liquid chromatography procedures is also provided. Unified chromatography is a promising tool for comprehensive multiclass analysis of dyes in the context of food safety.

Bound on 3+1 Active-Sterile Neutrino Mixing from the First Four-Week Science Run of KATRIN.

We report on the light sterile neutrino search from the first four-week science run of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are analyzed by a high-resolution MAC-E filter down to 40eV below the endpoint at 18.57keV. We consider the framework with three active neutrinos and one sterile neutrino. The analysis is sensitive to the mass, m_{4}, of the fourth mass state for m_{4}^{2}≲1000 eV^{2} and to active-to-sterile neutrino mixing down to |U_{e4}|^{2}≳2×10^{-2}. No significant spectral distortion is observed and exclusion bounds on the sterile mass and mixing are reported. These new limits supersede the Mainz results for m_{4}^{2}≲1000 eV^{2} and improve the Troitsk bound for m_{4}^{2}<30 eV^{2}. The reactor and gallium anomalies are constrained for 100<Δm_{41}^{2}<1000 eV^{2}.

A statistical study of factors affecting natural biovinegar fermentation from pineapple peel waste

The objective of this work was to screen and evaluate the significant parameter which affected the natural fermentation of pineapple biovinegar. In this work, peel waste from local breed pineapple (Royal Pepina) was fermented naturally to produce an aromatic biovinegar. Full factorial design of Design Expert® was used to develop a random experimental run in which six parameters were screened off. They were the fermentation temperature (27 – 50 °C), fermentation time (5 – 28 days), fermentation condition (anaerobic and aerobic), the addition of glucose (0 – 7 %), the addition of yeast (0 – 0.3 %), and peel waste condition (slurry & juice). Three parameters were identified as significant factors, which were the condition of fermentation, fermentation temperature, and addition of glucose. The ANOVA of the model was statistically significant with R2 of 0.9948. The pineapple biovinegar produced in this work contained 3.18 % reducing sugar, 1.03 % ethanol, 3.03 % acid, 0.61 % acetic acid, 1.43 mg equi. AA/100mL ascorbic acid, pH of 3.16, 4.0 % sucrose, 8.0 °Brix total soluble solid, and 82.06 % DPPH free-radical scavenging activity of antioxidant in biovinegar. This result stood second highest after apple cider biovinegar when compared to commercially available biovinegar.

The redox dependence of titanium isotope fractionation in synthetic Ti-rich lunar melts

Equilibria between Ti oxides and silicate melt lead to Ti isotope fractionation in terrestrial samples, with isotopically light Ti oxides and isotopically heavy coexisting melt. However, while Ti is mostly tetravalent in terrestrial samples, around 10% of the overall Ti is trivalent at fO2 relevant to lunar magmatism (~ IW-1). The different valences of Ti in lunar samples, could additionally influence Ti stable isotope fractionation during petrogenesis of lunar basalts to an unknown extent. We performed an experimental approach using gas mixing furnaces to investigate the effect of Ti oxide formation at different fO2 on Ti stable isotope fractionation during mare basalt petrogenesis. Two identical bulk compositions were equilibrated simultaneously during each experiment to guarantee comparability. One experiment was investigated with the EPMA to characterize the petrology of experimental run products, whereas the second experiment was crushed, and fabricated phases (i.e., oxides, silicates and glass) were handpicked, separated and digested. An aliquot of each sample was mixed with a Ti double-spike, before Ti was separated from matrix and interfering elements using a modified HFSE chemistry. Our study shows fO2-dependent fractionation within seven samples from air to IW-1, especially ∆49Tiarmalcolite-melt and ∆49Tiarmalcolite-orthopyroxene become more fractionated from oxidized to reduced conditions (− 0.092 ± 0.028- − 0.200 ± 0.033 ‰ and − 0.089 ± 0.027- − 0.250 ± 0.049 ‰, respectively), whereas ∆49Tiorthopyroxene-melt shows only a minor fractionation (− 0.002 ± 0.017-0.050 ± 0.025 ‰). The results of this study show that Ti isotope fractionation during mare basalt petrogenesis is expected to be redox dependent and mineral-melt fractionation as commonly determined for terrestrial fO2 may not be directly applied to a lunar setting. This is important for the evaluation of Ti isotope fractionation resulting from lunar magmatism, which takes place under more reducing conditions compared to the more oxidized terrestrial magmatism.

Intensified constructed wetlands for the treatment of municipal wastewater: experimental investigation and kinetic modelling.

This study reports organics and nutrient removal performances of the intensified constructed wetlands, i.e., tidal flow-based microbial fuel cell (MFC) and tidal flow wetlands that received municipal wastewater. The wetland systems were filled with organic (coco peat, biochar) or waste (Jhama brick, steel slag) materials, planted with Phragmites australis or Chrysopogon zizanioides (Vetiver) species, and operated under three flood periods: 8, 16, 24 h. Input ammonia nitrogen (NH3-N), total nitrogen (TN), phosphorus (P), chemical oxygen demand (COD), and biochemical oxygen demand (BOD) load across the wetland systems ranged between 3-27, 12-78, 0.1-23, 36-1130, and 11-281 g/m2day, respectively; mean removal percentages were 60-83, 74-84, 95-100, 94-98, and 93-97%, respectively, throughout the experimental run. The wetland systems achieved similar organics and P removals; operational and media variation did not influence removal kinetics. All wetland systems achieved the highest TN removal (76-87%) when subjected to 24-h flood period. TN removal performances of waste material-based wetlands were comparable to organic media-based systems. Tidal flow-based MFC wetlands achieved better TN removal than tidal flow wetlands because of supplementary electron production through fuel cell-based organics degradation kinetics. Maximum power production rates across the tidal flow-based MFC wetlands ranged between 53 and 57 mW/m2. Monod kinetics-based continuous stirred tank reactor (CSTR) models predicted NH3-N, TN, and COD removals (in wetland systems) more accurately. Kinetic models confirmed the influence of substrate (i.e., pollutant) and environmental parameters on pollutant removal routes.

Wave–bottom interaction and extreme wave statistics due to shoaling and de-shoaling of irregular long-crested wave trains over steep seabed changes

Abstract

Phosphorous doped g-C3N4 supported cobalt phthalocyanine: An efficient photocatalyst for reduction of CO2 under visible-light irradiation

The photoreduction of the green-house gas CO2 into carbon monoxide (CO) is a growing process due to the use of CO for the production of methanol in the Fischer-Tropsch process and the synthesis of many of the bulk chemicals. Here, we have synthesized phosphorous doped graphitic carbon nitride (P-g-C3N4) sensitized by the cobalt phthalocyanine complex for the molecular reduction of CO2 into CO under visible-light irradiation—the doping of phosphorous improved the stability as well as the harvesting of the visible region. The CoPc@P-g-C3N4 hybrid photocatalyst exhibited the highest efficiency for the photoreduction of CO2 with a high yield of 295 μmol-g−1 for CO under the experimental conditions. Also, hydrogen with low concentration was identified as a by-product under the experimental conditions. The photocatalyst had stability for six consecutive runs with negligible loss of the activity and no leaching of the cobalt content at the end of the sixth run of the photoreduction experiment. The stability of the photocatalysts is an advantage, which made it a suitable candidate for the current reaction system.

Global Impact of Cloud Longwave Scattering in an Atmosphere‐Only General Circulation Model Simulation

AbstractMost general circulation models (GCMs) neglect cloud longwave scattering in pursuit of computational efficiency. This study implements the 2‐/4‐stream (2/4S) method, a relatively fast cloud longwave scattering treatment, in Community Atmospheric Model version 5 (CAM5) to analyze the impact of cloud longwave scattering on the large‐scale circulation. Two 45‐years‐long integrations are performed with prescribed sea surface temperature (SST). In the experiment run, cloud longwave scattering is included using the 2/4S method; in the control run, clouds only absorb in the longwave. The results show that cloud longwave scattering acts to enhance the cloud longwave (greenhouse) effect by reducing outgoing longwave radiation (OLR) and enhancing downward longwave irradiance at the surface. The OLR reduction is most significant over the tropics, where surface temperatures and cloud elevations are high. The surface downward irradiance increase is most significant over polar areas and the Tibetan Plateau, where cloud elevations are low and the air below clouds is dry. Inclusion of cloud longwave scattering enhances the Walker circulation, suggestive of the importance of diabatic radiative heating in the tropical circulation. Inclusion of cloud longwave scattering also appears to shift the eddy‐driven jet poleward in the austral summer in the Southern Hemisphere, suggesting that the cloud longwave effect plays a role in shaping the jet position. Persistent equatorward jet biases in GCMs may be reduced if cloud longwave scattering is considered.

False Seedbeds Reduce Labor Requirements for Weeding in Chile Pepper

This study evaluated false seedbeds, which are sequences of irrigation and tillage that eliminate weed seedlings before crop planting, to reduce requirements for hand hoeing in chile pepper (Capsicum annuum). To address this objective, a field study was conducted near Las Cruces, NM from July 2015 to Oct. 2016 (experimental run 1) and July 2016 to Oct. 2017 (experimental run 2). False seedbeds were designed to target weeds that typically emerge after chile pepper planting. This was done by implementing false seedbeds the summer before chile pepper seeding. During chile pepper seasons, data included repeated measures of weed seedling emergence, amounts of time required for individuals to hoe field sections (i.e., hoeing time), and yields of two chile products: early harvest of green fruit and late harvest of red fruit. Hoeing time and yield data were included in cost–benefit analyses that also incorporated expenses and revenues projected by crop budget models for the study region. Results indicated false seedbeds caused a 54% decrease in weed population density during the chile pepper season of experimental run 1; however, for experimental run 2, false seedbeds did not affect cumulative weed seedling emergence. For both experimental runs, false seedbeds reduced hoeing times, suggesting that false seedbeds affected hoeing by means other than reduced weed density. After accounting for costs for implementation, false seedbeds reduced hand hoeing costs by $262/acre to $440/acre. These reductions in hoeing costs coincided with improved profitability in all but one combination of year and product. Green fruit yield was lower in false seedbed plots in experimental run 1; however, false seedbeds did not affect green fruit yield in experimental run 2, or red fruit yield in both experimental runs. These results indicate that false seedbeds implemented the summer before planting are promising techniques for reducing labor requirements for weeding in chile pepper production.

Experimental study of flows over Block Ramps on stability of non-cohesive beds

Block ramps are ecofriendly drop structures, which ensure more stability in the downstream riverbed. The scouring in the stilling basin bed material generated by the rapidly varied flow transition affects the stability of the ramp structure. In the present study, a modified stilling basin bed configuration is tested along with the uniform conventional stilling basin bed arrangements to check the stability of non-cohesive beds downstream to block ramps. Uniform non-cohesive horizontal bed configurations and bed with sill arrangement are tested for varying block ramp slopes (20% ≤ i ≥ 30%). The critical particle densimetric Froude number (Fc*) is selected as the criteria to predict the hydraulic conditions for incipient sediment motion in the uniform beds and it is compared with the established literature formulations to estimate the stability of the beds under macroroughness conditions. Scour volumes from each experimental run is quantified and the intensity of sediment motion is determined and related with the critical particle densimetric Froude number. The findings of the paper also describe the effect of Fc* on dimensionless scour depth. Spatial shift in the maximum scour depth formation from the toe of the block ramp for the tested flows over the bed sill arrangement has been observed. Experimental observations and comparison of results show the effect of sill gradation pronounced for non-uniform bed configuration, which effectively reduce the scour depth henceforth it stabilizes the upstream block ramp structure relative to the uniform beds selected.

Simultaneous optimization of machine and tool parameters for EDM using WC/Co P/M electrode made with micron and nano sized particles

Multi-response characteristic optimization is the most desired aspect of the components produced from electric discharge machining (EDM). Obtaining the optimal combination of parameters for surface roughness (SR) and micro-hardness (MH) is always a challenging task as the machining parameters favourable to one performance measure adversely affects the other. The present paper deals with the simultaneous optimization of SR and MH of D2 alloy steel during EDM with tungsten carbide (WC)/cobalt (Co) P/M electrode by considering electrode and machine tool parameters. Experimental run order was planned with Taguchi’s orthogonal arrays (OA) and in the present investigation, it is based on L18 OA. The analysis of variance (ANOVA) performed for the grey relational grade (GRG) showed that the tool parameter “particle size” (PS) is the most influential factor (61.43%) for simultaneous improvement of performance measures. The P/M electrode made of fine particle size (i.e., at nano level) has improved the process stability and reduced the arcing and short-circuiting results in reduced surface roughness. Simultaneously, the formation of the hard intermetallic phase’s viz., Fe3C, Cr23C6, W2C, Fe6W6C, and Cr2Fe14C on the EDMed surface has increased the surface hardness. The optimal set of parameters was validated through confirmation experiments.