Balance Experiments Research Articles

Thermal design of a frequency hopping processor

Abstract To solve the difficult problems in the thermal design of a new frequency-hopping processor, such as high heat consumption, concentrated local heat flux of the device, and large thermal resistance, a thermal design scheme was proposed to optimize the structure design and enhance the thermal conductivity of PCB board. At the same time, a combined scheme of copper water heat pipe-thermal expansion plate was used. Flotherm was used for thermal simulation and a thermal balance experiment under vacuum conditions was designed. Then the temperature of the frequency-hopping processor was measured experimentally to further verify the rationality of the design scheme. The combined scheme of copper water heat pipe-thermal expansion plate will guide the thermal design of this type of frequency hopping processor.

Corporate responses to systemic risk: Talk and action

Using text-mining analyses, we find that firms are more concerned about systemic shocks, leading to a subsequent decrease in systemic risk exposure. This finding is robust to endogeneity using the entropy balance, instrumental variable, and quasi-natural experiment tests. A tighter regulatory environment and increased risk aversion are primary reasons for aligning firms’ slogans with their actions, i.e., reducing expenses and increasing cash holdings, to mitigate systemic risk exposure. Importantly, these risk-mitigating strategies produce positive outcomes, including increased earnings and decreased bankruptcy risk for firms. Results suggest regulators can cultivate voluntary reductions in systemic risk by increasing firms’ awareness.

Aerobic denitrifying bacterial community with low C/N ratio remove nitrate from micro-polluted water: Metagenomics unravels denitrification pathways

The efficient nitrogen removal from micro-polluted source water is an international challenge to be solved urgently. However, the inner denitrification mechanism of native aerobic denitrifying bacterial communities in response to carbon scarcity remains relatively unclear. Here, the bacterial community XT6, screened from an oligotrophic reservoir, exhibited aerobic denitrifying capacity under low-carbon environments. Up to 76.79–81.64 % of total organic carbon (TOC) and 51.48–67.60 % of NO3−-N were removed by XT6 within 48 h at C/N ratios of 2.0–3.0. Additionally, the nitrogen balance experiments further manifested that 26.27–38.13 % of NO3−-N was lost in gaseous form. As the C/N ratio decreased, XT6 tended to generate more extracellular polymeric substances (EPS), with the tightly bound EPS showing the largest increase. Pseudomonas and Variovorax were quite abundant in XT6, constituting 59.69 % and 28.65 % of the total sequences, respectively. Furthermore, metagenomics analysis evidenced that XT6 removed TOC and nitrate mainly through the tricarboxylic acid cycle and aerobic denitrification. Overall, the abovementioned results provide a deeper understanding of the nitrogen metabolic pathways of indigenous aerobic denitrifying bacterial communities with low C/N ratios and offer useful guidance for controlling nitrogen pollution in oligotrophic ecosystems.

Evaluation of the Mineral Manganese OXMN009 and OXMN009P in the Chemical Looping Combustion (CLC) Process Using Thermogravimetry

Indirect combustion with the chemical looping combustion (CLC) of solid oxygen carriers is one of the most promising technologies for capturing carbon dioxide (CO2) in energy production from fossil fuels since the separation of the generated CO2 is inherent to the process itself. Therefore, the cost associated with capturing this gas will be significantly reduced. This technology transfers oxygen from air to fuel through a metal oxide that acts as an oxygen carrier, avoiding direct contact between air and fuel. This oxygen carrier circulates in a fluidized bed reactor called a reduction reactor and an oxidation reactor. (1) This research work has focused on evaluating the behavior of oxygen carriers based on the original and improved manganese mineral (copper-impregnated mineral) named for this study, OXMN009 and OXMN009P, respectively. (2) Equilibrium experiments were carried out on a thermogravimetric balance (TGA) to evaluate the kinetic behavior of these oxygen transporters OXMN009 and OXMN009P, using the gases methane (CH4), carbon monoxide (CO), and hydrogen (H2). (3) The enhanced solid oxygen carrier OXMN009P exhibited good performance for the CLC process with gaseous fuels in terms of reactivity and combustion efficiency, having high reactivity and oxygen transfer properties due to copper impregnation. (4) The results show that OXMN009P has comparable reactivity to other manganese-based materials reported in the literature. It may be an effective option for carbon dioxide capture, as it uses metal oxides as the oxygen transporters (TO). (5) These oxygen transporters, OXMN009 and OXMN009P, are used in a cyclic process that prevents the formation of nitrogen oxides by keeping the air and fuel separate. (6) Thermogravimetric balance (TGA) experiments were conducted to evaluate the kinetic behavior of these copper-modified oxygen transporters. (7) It was found that OXMN009P improved the reactivity and oxygen transfer properties due to copper impregnation. The kinetic parameters obtained in the TGA indicate that the reaction is non-thermal and requires less energy to initiate. (8) The results show that OXMN009P has reactivity comparable to other manganese-based materials reported in the literature and can be an effective option for carbon dioxide capture.

Blowing in the dark matter wind

Interactions between dark matter and ordinary matter will transfer momentum, and therefore give rise to a force on ordinary matter due to the dark matter ‘wind.’ We show that this force can be maximal in a realistic model of dark matter, meaning that an order-1 fraction of the dark matter momentum incident on a target of ordinary matter is reflected. The model consists of light (mϕ ≲ eV) scalar dark matter with an effective interaction ϕ2ψ¯ψ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {\\phi}^2\\overline{\\psi}\\psi $$\\end{document}, where ψ is an electron or nucleon field. If the coupling is repulsive and sufficiently strong, the field ϕ is excluded from ordinary matter, analogous to the Meissner effect for photons in a superconductor. We show that there is a large region of parameter space that is compatible with existing constraints, where the force is large enough to be detected by existing force probes, such as satellite tests of the equivalence principle and torsion balance experiments. However, shielding of the dark matter by ordinary matter prevents existing experiments from being sensitive to the dark matter force. We show that precise measurements of spacecraft trajectories proposed to test long distance modifications of gravity are sensitive to this force for a wide range of parameters.

Distribution characteristics of sulfonamide antibiotics between water and extracellular polymeric substances in municipal sludge

The interaction between extracellular polymeric substances (EPS) in municipal sludge and antibiotics in wastewater is critical in wastewater treatment, resource recovery, and sludge management. Therefore, it is increasingly urgent to investigate the distribution coefficient (Log K) of sulfonamide antibiotics (SAs) in EPS, particularly in sludge-derived dissolved organic carbon (DOC) and aqueous phase systems. Herein, through balance experiments, the concentrations of SAs were determined using alkaline extraction EPS (AEPS) and alginate-like extracellular polymer (ALE) systems, and the Log KDOC values were determined. The results showed that the Log KDOC of AEPS was higher than that of ALE, which exhibited a negative KDOC value, indicating an inhibitory effect on dissolution. For the three SAs studied, the Log KDOC values were in the following order: sulfamethoxazole > sulfapyridine > sulfadiazine. This order can be attributed to the differing physicochemical properties, such as polarity, of the SAs. Three-dimensional excitation–emission matrix fluorescence spectra and fitting results indicated a lack of aromatic proteins dominated by tryptophan and humus-like substances in ALE. Meanwhile, the hydrophobic interaction of aromatic proteins dominated by tryptophan was the main driving force in the binding process between AEPS and SAs.

A novel magnet system—which enables uniformity of radial flux density by means of a parabolic yoke—applied in the Planck-Balance

Abstract A uniform magnetic flux density that is effective in the movement range of the coil is essential for accurate Kibble balance experiments. By utilizing Hopkinson’s law and Kirchhoff’s circuit laws, basic formulas have been derived, providing a method to calculate the magnetic flux density distribution in the airgap of a cylindrical magnet system. A parabolic outer contour of the inner yoke has been found to be a suitable solution to achieve uniformity. Experiments show, that this approach results in a relative change of magnetic flux density in the order of 3 ⋅ 10 − 4 per 8 mm movement range, using a magnet system with a mass of only 2.3 kg. Therefore, the system will be integrated into the upgraded version of PTB’s Planck-Balance—a compact variant of a Kibble balance—aiming for sub 1 ⋅ 10 − 6 accuracy level determination of the geometric factor. The solution described provides a comparatively easy means to design a cylindrical magnet system, using only one permanent magnet disc, without the use of complex simulation software.

Оптимизация технологических параметров хлорирующего обжига окисленной составляющей изгари

To date, in the world zinc production, the main share of zinc consumption up to 50% is accounted for by the processes of galvanizing products. An important factor affecting the efficiency of the hot-dip galvanizing process is the loss of zinc associated with the formation of surface (zinc burn) and bottom (gartzink) waste. Of great interest for the processing of dross is the use of metal chlorination technology. The optimal technological parameters of the firing process were established in the work, where deep sublimation of impurity metals was achieved to obtain pure zinc oxide, suitable for use as a mineral additive in animal and bird feed. It was found that the use of a mixture of chlorinating reagents with a consumption of CaCl2 and NH4Cl of 3% and 7%, respectively, provides high-quality commercial zinc oxide with a minimum content of impurities, % wt: 0.02 Pb; 0.04 Fe; 0.01 Ni; 0.01 Cu; Cd traces. Optimal technological parameters and firing process modes were established: temperature – 1000°C; duration – 60 minutes; chlorinating reagent – mixture (CaCl2 + NH4Cl): CaCl2 consumption – 3% of the weight of the initial sample; NH4Cl consumption – 7% of the weight of the initial sample; air consumption – 0.1 l/min. In this paper, the results obtained will be used to conduct balance experiments on firing the oxidized component of the dross together with chlorinating reagents.

PERSPECTIVE: Interfacial stresses in thin film drainage: Subtle yet significant

Film drainage, essential in droplet and bubble coalescence and surface wetting, is influenced strongly by the stress boundary condition, in particular, when interfacial stresses are present. These stresses, caused by ubiquitous surface-active components, significantly impact the dynamics of liquid films. Through dynamic thin film balance experiments, we compare the effects of Marangoni stresses, interfacial viscosity, and interfacial viscoelasticity on the drainage of free-standing thin liquid films. These data serve to demonstrate that film deformation intricately depends on the interplay between these stresses and capillarity, resulting in widely varied drainage times. Seemingly subtle changes, especially in the local stress-carrying capacity of the interface, can lead to significant differences in film dynamics. This makes it a promising area for research into interfacial-rheologically active materials for stabilizing potentially more sustainable multiphase materials.

The impact of time constraints on new venture investment decisions: an experimental study

ABSTRACT Researchers have suggested that new venture investors quickly conclude their decisions and rely on heuristics. However, there is a paucity of empirical work exploring the impact of time constraints on new venture investment decisions. To fill this gap, we are exploring the impact of time constraints on the new venture investment decision process and the final investment decision using the arguments of the Dual Process Theory. A balanced experiment setup is used, where the treated group is given time constraints to make the decision. Results show that investors under time constraints consider only a subset of the available information signals to perceive the probable prospects and to make final investment decisions. This consideration of a subset of information signals results in a partial assessment of the proposal where investors focus more on return potential than risk exposure aspect of investment proposals. This inclination towards return potential increases the scale of investment.

Deep-Learning Correction Methods for Weather Research and Forecasting (WRF) Model Precipitation Forecasting: A Case Study over Zhengzhou, China

Systematic biases and coarse resolutions are major limitations of current precipitation datasets. Many studies have been conducted for precipitation bias correction and downscaling. However, it is still challenging for the current approaches to handle the complex features of hourly precipitation, resulting in the incapability of reproducing small-scale features, such as extreme events. In this study, we proposed a deep-learning model called PBT (Population-Based Training)-GRU (Gate Recurrent Unit) based on numerical model NWP gridded forecast data and observation data and employed machine-learning (ML) methods, such as Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbor (KNN), and Gradient-Boosted Decision Tree (GBDT), to correct the WRF hourly precipitation forecasts. To select the evaluation method, we conducted a sample balance experiment and found that when the proportion of positive and negative samples was 1:1, the Threat Score (TS) and accuracy scores were the highest, while the Probability of Detection (POD) score was slightly lower. The results showed that: (1) the overall errors of the PBT-GRU model were relatively smaller, and its root mean square error (RMSE) was only 1.12 mm, which was reduced by 63.04%, 51.72%, 58.36%, 37.43%, and 26.32% compared to the RMSE of WRF, SVM, KNN, GBDT, and RF, respectively; and (2) according to the Taylor diagram, the standard deviation (σn) and correlation coefficient (r) of PBT-GRU were 1.02 and 0.99, respectively, while the σn and r of RF were 1.12 and 0.98, respectively. Furthermore, the σn and r of the SVM, GBDT, and KNN models were between those of the above models, with values of 1.24 and 0.95, 1.15 and 0.97, and 1.26 and 0.93, respectively. Based on a comprehensive analysis of the TS, accuracy, RMSE, r and σn, the PBT-GRU model performed the best, with a significantly better correction effect than that of the ML methods, resulting in an overall performance ranking of PBT-GRU > RF > GBDT > SVM > KNN. This study provides a hint of the possibility that the proposed PBT-GRU model can outperform model precipitation correction based on a small sample of one-station data. Thus, due to its promising performance and excellent robustness, we recommend adopting the proposed PBT-GRU model for precipitation correction in business applications.

Simultaneous removal of calcium, phosphorus, and bisphenol A from industrial wastewater by Stutzerimonas sp. ZW5 via microbially induced calcium precipitation (MICP): Kinetics, mechanism, and stress response

The biological treatment of complex industrial wastewater has always been a research hotspot. In this experiment, a salt-tolerant strain Stutzerimonas sp. ZW5 with aerobic denitrification and biomineralization ability was screened, and the optimum conditions of ZW5 were explored by kinetics. The removal efficiencies of nitrate (NO3--N), bisphenol A (BPA), phosphorus (PO43--P), and calcium (Ca2+) were 94.47 %, 100 %, 98.87 %, and 83.04 %, respectively. The removal mechanism of BPA was the adsorption of microbial induced calcium precipitation (MICP) and extracellular polymeric substances (EPS). Moreover, BPA could weaken the electron transfer ability and growth metabolism of microorganisms and affect the structure of biominerals. At the same time, the stress response of microorganisms would increase the secretion of EPS to promote the process of biomineralization. Through nitrogen balance experiments, it was found that the addition of BPA would lead to a decrease in the proportion of gaseous nitrogen. This experiment offers novel perspectives on the treatment of industrial effluents and microbial stress response.

Assembly Structure Formation in Bulk and Ultrathin Films of Poly(substituted methylene) Having an Azobenzene Side Chain.

The density of the side chain introduced to a polymer main chain greatly influences the properties and functions of the polymer. This work first reports on the packing structure and properties at an interface of a poly(substituted methylene) where an azobenzene side chain is introduced at every carbon atom in the main chain (C1PAz). The structure and properties are compared with those of a conventional vinyl polymer [poly(methacrylate)] possessing an identical side-chain structure (C2PAz). The packing structure in the bulk state analyzed by X-ray measurements revealed that C1PAz adopts a highly ordered rectangular unit cell structure, whereas C2PAz shows a less ordered lamellar one. Langmuir film balance experiments indicated that both polymers with the trans-azobenzene give essentially the identical 2D side-chain occupying area on water, which agrees well with the smectic B (hexatic packing) model based on the X-ray data. Upon transfer onto a solid substrate, only C1PAz shows a conformational transformation to a spread bilayer-type layer, most probably due to conformational frustration stemming from the crowding of the side chains. This study proposes new insights into the effects of side-chain density on the self-assembly and photoreaction of azobenzene-containing polymers, which are expected to expand the possibilities of polymer design for various applications.

High-accuracy determination of the beam divergence error in free-fall absolute gravimeters

We investigate the bias due to the beam divergence of the collimator in a free-fall absolute gravimeter of type FG5X. First, we measure the beam parameters with a Shack-Hartmann sensor. Then, we use the parameters to simulate the relative gravitational acceleration error of an FG5X gravimeter, which employs an unbalanced Mach-Zehnder laser interferometer. This investigation we do with four different commercial collimators, providing different divergence angles. We compare the results to real gravity measurements using the same collimators. The larger the divergence angle, and the bigger the relative length error, the bigger is the bias in the gravity measurements. A good agreement between theory and experiment is found, resulting in a relative bias of −2.77(24)⋅10−9 ( −2.72(24) μGal) for our standard collimator of type Thorlabs TC25APC, which is usually used for free-fall acceleration determinations. The outcome is also important for the realization of the SI unit kilogram via Kibble balance experiments that, on one side, employ laser interferometers for velocity measurements, and, on the other side, require accurate values of the gravitational acceleration. For example, if this divergence error is not corrected in the Kibble balance, then the mass determination would be biased by 2.77(24) μg kg−1 (numbers are valid only for our gravimeter with our collimator and fiber).

Influence of genotype of lam on the consumption and use of nutrients in the diets

Relevance. The results of a study of the consumption and use of dietary nutrients by purebred and crossbred rams are presented.Methodology. To conduct the study, experimental groups of rams were formed from newborn young animals: I— Romanovskaya breed, II— 1/2Romanovskaya × 1/2edilbai, III— × 1/4Romanovskaya × 3/4edilbai. To study the consumption and use of nutrients in the diet, a balance experiment was carried out using the VIZh method (A.I. Ovsyannikov, 1976).Results. It has been established that crossbred young animals consume and use the nutrients of the diet most intensively. It is enough to note that the coefficient of digestibility of nutrients by young animals of the experimental group III was higher than by young animals of groups I and II, on average by 0.3–1.75. The results obtained indicate that crossbred young animals of groups II and III made better use of dietary nutrients than purebred peers. At the same time, crossbred young animals of group III were characterized by a better ability to digest nutrients in diets.

Hulless barley as part of the diets for quails of the parental herd

Every year in our country the production of poultry products increases. Currently, in many countries of the world quail farming is intensively developing, the task of which is to meet the needs of the population with high-quality and environmentally friendly eggs and meat that have dietary properties. A priority direction in the development of modern poultry farming is the search for new cost-effective and highly effective feed products based on local raw materials that can provide a solution to the problems of complete feeding. Currently, the search for new sources of grain crops with high protein and energy nutrition is relevant. The introduction of hulless barley varieties with a fiber content of 1,6 to 2,8 % into compound feed will increase the digestibility of nutrients. Therefore, the use of hulless barley as part of feed for quails is of certain feasibility. The purpose of the work was to establish the eff ect of compound feed with hulless barley on animal science and economic indicators when housing quail parental herd. The results of a research with the introduction in the diets of quail of 10 % hulless barley and its eff ect on the productivity of the parental herd have been presented in the article. It was established as a result of the research that the use of compound feed with the introduction of 10 % hulless barley for quail parental herd contributed to a reduction in the prime-cost of production of hatching eggs by 7,13 %, due to an increase in the productivity of laying quails by 11,38 % and the reduction in feed expenditures per 1 kg of egg mass and for 10 eggs by 5,09 and 1,70 %, respectively. It was established when carrying out a balance experiment that the use of the developed compound feed for poultry in the experimental group increased the digestibility of nutrients such as crude protein by 1,46 abs.% and crude fiber by 4,34 abs.%.

The use of soybeans in the structure of the ration of high-yielding cows

In the conditions of intensive milk production in order to ensure high productivity and at the same time preserve the general functional state of animal health it is impossible to do without the use of protein-rich grain components in the structure of compound feed. These include soybeans, which in the western region of Ukraine began to be widely used in the production of compound feed for cattle. The percentage of introduction of soybeans into the structure of compound feed is different and for high-yielding cows requires additional study, which explains the relevance of conducting research on its influence on milk productivity, quality indicators of milk against the background of assimilation of the main nutrients of feed. The study was conducted on four groups of Simmental cows, seven heads in each. The rations of experimental cows provided for three levels of provision of protein needs at the expense of soybeans and were balanced in terms of basic nutrients in compliance with the requirements of detailed requirements. The analysis of the feeding conditions of experimental cows showed that the use of heat-treated soybeans in the structure of the ration contributed to a significant increase in milk productivity, as well as quality indicators, the content of dry matter, fat, protein, calcium and phosphorus. A similar pattern was observed in terms of indicators of the intensity of metabolic processes of cicatricial digestion. Thus, a positive effect on the percentage of certain volatile fatty acids, in particular acetic as a precursor of milk fat was noted. An increase was noted in the digestibility indicators of the main nutrients (protein, fat, fiber digestibility coefficients). The positive effect of soybeans on the milk productivity of the experimental cows was also noted by the results of the balance experiment. The nitrogen balance was positive and its use for milk production in cows of the fourth group compared to the control group was 27.4 % higher. A similar trend was observed in the balance of calcium and phosphorus. So, the conducted studies on the study of the productive effect of different amounts of soybeans instead of cereal components in the structure of compound feed on milk productivity give reason to recommend that farms use prepared soybeans in the proportion of 10–15 % in compound feed for high-yielding cows.

Unbalanced Feature Identification of Rotor System Based on Fused Cross‐Correlation Fast Fourier Transform

Rotor system unbalance is one of the most important factors that affects the operating accuracy and stability in aerospace engineering. The extraction and identification of unbalanced features is the premise for the dynamic balance of rotor system. In order to accurately identify the unbalanced vibration feature, based on the fused cross‐correlation fast Fourier transform (FC‐CFFT) method, an unbalanced feature extraction method of the rotor system is proposed. The convolution window weighs the data of the vibration sequence and carries out delay processing. Through spectrum calculation, the phase information of the vibration signal is obtained. And the amplitude information of the vibration feature can be acquired through cross‐correlation calculation. The unbalanced features of the rotor system vibration signals are identified under different working conditions through simulation and experiment. The results show that this method is more accurate than FFT, the cross‐power method, and the sine‐approximation method in extracting different unbalanced vibration features of the rotor system. The extraction accuracy of unbalanced feature phase and amplitude reaches 98.61% and 97.27%, respectively. After the unbalanced feature is extracted, the dynamic balance experiment can be carried out. The unbalanced feature is used for dynamic balance compensation. In this way, the average amplitude decreased by 76.35%. The high accuracy of the FC‐CFFT method for extracting the unbalanced feature has been verified. This research provides a theoretical foundation for the vibration signal processing and dynamic balance control of the rotor system.

Notes on correctness of p-values when analyzing experiments using SAS and R.

It is commonly believed that if a two-way analysis of variance (ANOVA) is carried out in R, then reported p-values are correct. This article shows that this is not always the case. Results can vary from non-significant to highly significant, depending on the choice of options. The user must know exactly which options result in correct p-values, and which options do not. Furthermore, it is commonly supposed that analyses in SAS and R of simple balanced experiments using mixed-effects models result in correct p-values. However, the simulation study of the current article indicates that frequency of Type I error deviates from the nominal value. The objective of this article is to compare SAS and R with respect to correctness of results when analyzing small experiments. It is concluded that modern functions and procedures for analysis of mixed-effects models are sometimes not as reliable as traditional ANOVA based on simple computations of sums of squares.

Simultaneous inorganic nitrogen and phosphate removal by aerobic-heterotrophic fungus Fusarium keratoplasticum FSP1: Performance, pathway and application

Fungi with multiple contaminant removal function have rarely been studied. Here, a novel fungal strain Fusarium keratoplasticum FSP1, which was isolated from halophilic granular sludge, is reported for first time to perform simultaneous nitrogen and phosphate removal. The strain showed wide adaptability under C/N ratios of 30–35, salinities of 0 %–3 % (m/v), and pH of 7.5–9.5. The maximum removal rates of ammonium, nitrate and nitrite were 4.43, 4.01 and 2.97 mg N/L/h. The nitrogen balance, enzyme activity and substrate conversion experiments demonstrated a single strain FSP1 can assimilate inorganic nitrogen and convert inorganic nitrogen to gaseous nitrogen through heterotrophic nitrification or aerobic denitrification. About 39 %–42 % of the degraded phosphorus was in the extracellular polymeric substances (EPS). Orthophosphate was the main phosphorus species in the cell, whereas phosphate monoester and diester were in the EPS. The novel strain FSP1 is a potential candidate for wastewater treatment.