A Comprehensive Study on Intermittent Operation of Horizontal Deep Borehole Heat Exchangers

Utilizing a deep Borehole Heat Exchanger (BHE) has been recognized as a clean, renewable, low-carbon-emission, and sustainable way for heating of residential buildings and greenhouses. In this study, the long-term performance of horizontal deep BHE in intermittent mode is scrutinized. In this regard, to predict the transient heat transfer process in the deep BHEs, a mathematical model is developed and then verified by using the experimental results. The effect various key parameters including flow rate of circulating fluid, undisturbed ground temperature, inlet fluid temperature, and ground thermal conductivity on the thermal performance of deep BHE in continuous and intermittent mode is studied. According to the results, increasing the flow rate of circulating fluid, undisturbed ground temperature, and ground thermal conductivity is favorable for heat extraction rate. Moreover, the effect of three specific parameters for intermittent operation including periodic time interval, flow rate ratio, and recovery period ratio on the long-term performance of horizontal deep BHE are scrutinized. Based on the results, by decreasing the periodic time interval and increasing the flow rate ratio, the mean heat extraction rate in the period of 30 years is increased and the mean borehole’s wall temperature is decreased. Furthermore, by increasing the recovery period ratio, the heat extraction rate increases significantly while the total extracted energy decreases.

Analysis of Volleyball Video Intelligent Description Technology Based on Computer Memory Network and Attention Mechanism

There are some problems in the process of video intelligent description and analysis of volleyball, such as poor effective information extraction rate and poor dynamic tracking effect. Based on this, combined with long-term and short-term memory network and attention mechanism, this paper designs an intelligent description model of volleyball video based on deep learning algorithm and studies how to improve the extraction rate of volleyball video information through intelligent detection hardware and image recognition technology. This paper first introduces the application of image recognition technology and deep learning algorithm in the intelligent description of volleyball video, then designs the volleyball video and image recognition model based on deep learning algorithm according to the requirements of volleyball video intelligent description, and selects three correlation factors related to the impact indicators of volleyball skills. This study selects three characteristic parameters associated with volleyball video analysis indexes, namely, take-off, bounce, and hand movement, combined with image sensing hardware assisted sensor network to realize real-time monitoring of action state in volleyball video analysis system. The experimental results show that, compared with the current mainstream sports video intelligent analysis and image recognition methods with data analysis as the core, the intelligent volleyball sports video intelligent description and image recognition system based on the integration of deep learning algorithm and sensor hardware assistance has the advantages of good detection effect, high data effectiveness, low cost, and high efficiency of volleyball sports video analysis. It can effectively improve the efficiency of volleyball video intelligent description.

Study on the optimization of spray drying process for Areca taro powder with microcystalline cellulose

Starch is a product of intensive processing of agricultural products. During the processing of plant starch, nutrients such as protein, dietary fiber, and minerals are removed. In addition to nutritional imbalance, rich nutrients have an impact on the environment. The object of research is Areca taro, a starch-rich agricultural product. The research aims to use spray drying technology to obtain a whole betel nut taro powder for food processing, such as sausages and noodles. The taro is used as a raw material, and the whole taro flour is obtained after peeling, cutting, crushing with water, and spray drying. Using single factor and orthogonal experiment to optimize the spray drying process parameters and embedding agent of taro powder, and then analyze its physical and chemical properties. The results show that adding 0.01 % Xanthan gum+0.12 % Microcrystalline cellulose (embedded agent) to the taro emulsion can increase the extraction rate of taro flour, speed up the drying speed, and prevent sticking to the wall. The best process of spray drying: the speed of atomizer was 16000 r/m, the wind temperature was 200 °C, the material liquid concentration was 28.00 % and the feeding rate was 75 mL/min. The taro powder produced by this process has better liquidity, light purple color, smooth texture, and strong flavor of taro. Product parameters: powder fluidity was 13.9 cm, extraction rate was 15.36 %, water activity was 0.416, chromaticity parameters were 19.73 (L* value), 2.96 (a* value) and 3.25 (b* value), bulk density was 0.44 g/mL. This technology can provide data support and reference for food processing companies. The taro whole powder would be widely used as food ingredients in future.

Investigating antioxidant and antibacterial activity of functional cookies enriched with beetroot during storage

Beetroot (Beta vulgaris L.) is one of the plants that contain biologically active compounds that have a function in the prevention and treatment of a wide variety of diseases. The study aims to design new cookies that will support certain groups, such as schoolchildren who may be anaemic. Also, to determine four cookie treatments that were planned to substitute white wheat flour with extraction rate of 72% as follows: T₀ (0%), T₁ (2.5%), T₂ (5.0%), T₃ (7.5%), and T₄ (10%) of beetroot powder to replace 100 g of flour; the cookies were baked at 180 °C for 30–35 min. The chemical composition was assessed, included total phenols, flavonoids, and minerals. Furthermore, during a three-week storage period, antioxidant activity and betalain pigments were evaluated, and sensory evaluation and microbiological assessment were done. Sensory evaluation revealed that the replacement ratio of 10% beetroot was acceptable to the cookies manufactured from white wheat flour with extraction rate of 72%. Compared to the control, a slight decrease was found in the total count of bacteria, fungi, and moulds. We recommend baking beetroot-enriched cookies since it enhances the organoleptic and microbiological characteristics.

IMPACT OF NEODYMIUM AND SCANDIUM IONIC RADII ON SORPTION DYNAMICS OF AMBERLITE IR120 AND AB-17-8 REMOTE INTERACTION

The aim of this research work is comparative study of influence of ionic radii of heavy metal ions of neodymium and scandium on their sorption process from corresponding water solutions of sulfates by sorbents such as individual ion-exchangers Amberlite IR120, AB-17-8 and mixture of these sorbents related to interpolymer system Amberlite IR120-AB-17-8 at the various molar relations. Laboratory experiments of this work of sorption heavy ions of neodymium and scandium were carried out and inves-tigated by using the following physico-chemical methods of analysis: conductometry-based on the electrical conductor, pH-metry-based on the concentration of hydrogen ions, colorimetry, atomic-emission spectro-scopy. Ion-exchangers in the interpolymer system undergo remote interaction with further transition into highly ionized state. There is formation of optimal conformation in structure of the initial ion- exchangers. Significant increase of ionization of the ion-exchange resins occurs at molar ratio Amberlite IR120:AB-17-8 = 5:1. Significant increase of sorption properties is observed at this ratio due to mutual activation of ion-exchangers. The extraction rate of Nd3+ ions in 48 hours is 42.32%, and the extraction rate of Sc3+ ions is 38.06%. A possible reason for higher sorption of neodymium ions in comparison with scandium ions is maximum conformity of globes of internode links of Amberlite IR120 and AB-17-8 after activation to sizes of neodymium sulfate in an aqueous medium.

Effect of Ultra-Fine Grinding on the Structure of Plant Raw Materials and the Kinetics of Melanin Extraction

Enhancing the extraction rate is one of the key objectives in optimization of extraction of substances from biogenic raw materials. Ultra-fine grinding of plant raw materials (to achieve particle size less than 300 µm) is a very appealing method for increasing the extraction rate using relatively simple equipment. However, this approach often fails to yield the desired result. This study focuses on the kinetics of melanin extraction from two types of raw materials: fungus Ganoderma applanatum and buckwheat husk. Particle size is shown to be just one of the key factors. The degree of order of plant-based feedstock strongly affects the intraparticle diffusion constants and can be a parameter controlling the diffusion rate. It has been shown that there exist optimal degrees of disorder of the crystal structure of plant raw materials, which have a dome-shaped dependence pattern and allow one to increase the diffusion coefficient by several dozen times. The kinetics of melanin extraction was described by some kinetic models that include the first order equation, the Baker and Lonsdale model, the Axelrud equation, and the Ritger–Peppas model.

Evaluation of the hyperbaric oxygen therapy on the flash visual evoked potential P2 in patients with severe traumatic brain injury

BACKGROUND: Studies have shown that hyperbaric oxygen therapy (HBOT) can improve the extraction rate and latency of cortical evoked potential N20 in patients with severe traumatic brain injury, but there are only a few studies on the effect of flash visual evoked potential. OBJECTIVE: This study investigated the effect of hyperbaric oxygen therapy on the P2 wave of flash visual evoked potentials in patients with severe traumatic brain injury. METHODS: In total, we examined 40 TBI patients who received HBOT, in combination with medication, and 38 TBI patients who received medication alone. The FVEPs apparatus was used to detect the P2 wave extraction rate and the latency of the elicited waveform before and after treatment in both the medicated-only controls and HBOT-treated cohorts. RESULTS: Compared with the control group, the HBOT treatment group showed a higher P2 wave elicitation rate, and the P2 wave latency of the HBOT treatment group was significantly shortened (p < 0.05, all). CONCLUSIONS: HBOT, in combination with drug therapy, can significantly increase the P2 wave extraction rate and shorten P2 latency in patients with TBI.

Intraoperative hyperglycemic stress response and tissue perfusion in cardiac surgery

Background and aim of the study Approximately 30% of patients undergoing cardiac surgery have a history of diabetes and 60-80% of patients without diabetes have stress hyperglycemia. We examined patients undergoing cardiac surgery to determine the presence of stress hyperglycemia and its relationship to tissue perfusion. Methods Hemodynamic parameters, central venous oxygen saturation, lactate,oxygen delivery and consumption, oxygen extraction rate were analyzed at four intraoperative time points. Results The stress-induced hyperglycemic response during cardiac surgery was more severe in patients without diabetes. When focusing on the oxygen extraction rate in terms of tissue oxygenation, diabetic patients had 1.22 times higher and significant oxygen extraction rate than non-diabetic patients. Conclusions Although lactate values were slightly higher and central venous oxygen saturation were slightly lower in the diabetic group, considering the fact that oxygen extraction rate reflects the total outcome of small changes in all these parameters, we can emphasize the conclusion that diabetic patients undergoing cardiac surgery have greater tissue oxygen demand/supply imbalance compared to non-diabetic patients. In our study, this tissue oxygenation defect in diabetic patients was not found to be directly correlated with blood glucose levels. Perhaps, even if the disease is under control, the negative effects of diabetes on all systems have accumulated and led to such a result.

Evaluating the Flour Properties under Different Levels of Particle Size Distribution and Fine Bran Content

The main objective of this study was to determine the changes in the rheological characteristics of the flour produced by the industry mill Buhler AG 600 ton/day through adding big particles of flour, semolina, and fine bran (FB) to the produced flour. The study was conducted on mixed wheat grains (80% Iraqi wheat and 20% American Red wheat). After changing the directions of some pipes in the milling section, the flours were tested, and the effect of having bigger particles in the product was measured. The results showed that the flour extraction rate, moisture content, ash, and protein were increased as the flour particle size was increased. Farinograph results explained a clear effect of big particles and fine bran on increasing the water absorption, however, the dough stability was decreased mostly insignificantly. Extensiograph results showed that there was no big difference between the control flour and other produced flour. Therefore, the changes of the mill pipes could increase the flour extraction rate and reduce the pressure on the mill rolls without significant differences in the rheological properties of the produced flour.