Extraction Flow Rate Research Articles

Research on the thermal balance of a novel independent heat extraction-release double helix energy pile in long-term operation

Ground source heat pump buried pipes offer potential in civil defense due to their concealment and reliability, yet face thermal imbalance issues. This paper adopts a double helix energy pile with independent heat extraction-release capacity and develops an experiment to compare the performance of independent operation versus joint operation. Furthermore, a verified 2D model facilitated extensive simulations for long-term thermal balance, integrating refrigeration load, principles of water use in an underground engineering, and heat pump model. Comparative experiments show that joint operation can effectively alleviate soil heat accumulation by more than 20%. Extended simulations reveal that as accumulated heat is removed, the unit's performance is improved, and soil heat accumulation can boost heat extraction. However, under domestic water heat extraction, the heat-extracting pipe shows low flow rates, leading to thermal accumulation, necessitating the use of water for equipment or additional feed water to improve heat extraction. Compared to uniform enhancement heat extraction, centralized enhanced heat extraction boosts overall heat extraction capacity by 35.1%, which can more effectively mitigate thermal imbalances and improve unit performance, and achieving thermal balance in the geotechnical area requires an enhanced extraction flow rate above 10.5 L/h, with over 56 m3 of water passing through the heat-extracting pipe.

Evaluating sustainability power plant efficiency: Unveiling the impact of power plant load ratio on holding steam ejector performance

Understanding the role of holding ejectors is essential in the broader context of environmental and sustainability research. Through rigorous analysis, optimization of ejector usage is applied to minimize resource consumption and promote cleaner, more sustainable production methods. However, the design and control strategies of the power plant, including the setpoints and tolerances of various components, can also contribute to the power plant load ratio (PPLR). This study explores the impact of PPLR in the power plant cycle on the holding ejectors performance under various condenser temperatures. For comprehensive analysis, the study employs a comprehensive framework encompassing various indicators such as condensing fluid behavior, energy consumption, exergy destruction, air suction in the condenser, and entrainment ratio. The research unveils key findings, including a notable increase in oblique shocks with rising PPLR and a quantifiable rise in the maximum liquid mass fraction in the condensed regime. Additionally, the analysis reveals numerical relationships, such as a 5 % increase in mass flow rate and a 4.9 % rise in energy consumption with a PPLR increase from 0 to +5 %. Negative impacts on performance, such as a 4.6 % reduction in air extraction flow rate from the condenser, are observed with PPLR changes from 0 to −5%.

Large-scale physical simulation of injection and production of hot dry rock in Gonghe Basin, Qinghai Province, China

Based on the independently developed true triaxial multi-physical field large-scale physical simulation system of in-situ injection and production, we conducted physical simulation of long-term multi-well injection and production in the hot dry rocks of the Gonghe Basin, Qinghai Province, NW China. Through multi-well connectivity experiments, the spatial distribution characteristics of the natural fracture system in the rock samples and the connectivity between fracture and wellbore were clarified. The injection and production wells were selected to conduct the experiments, namely one injection well and two production wells, one injection well and one production well. The variation of several physical parameters in the production well was analyzed, such as flow rate, temperature, heat recovery rate and fluid recovery. The results show that under the combination of thermal shock and injection pressure, the fracture conductivity was enhanced, and the production temperature showed a downward trend. The larger the flow rate, the faster the decrease. When the local closed area of the fracture was gradually activated, new heat transfer areas were generated, resulting in a lower rate of increase or decrease in the mining temperature. The heat recovery rate was mainly controlled by the extraction flow rate and the temperature difference between injection and production fluid. As the conductivity of the leak-off channel increased, the fluid recovery of the production well rapidly decreased. The influence mechanisms of dominant channels and fluid leak-off on thermal recovery performance are different. The former limits the heat exchange area, while the latter affects the flow rate of the produced fluid. Both of them are important factors affecting the long-term and efficient development of hot dry rock.

Development and validation of ivermectin quantification method in volumetric absorptive microsampling using liquid chromatography-tandem mass spectrometry

BackgroundIvermectin is a broad-spectrum anthelmintic used to control onchocerciasis from nematode parasites. As an anthelmintic, ivermectin is designed to have high levels in the gastrointestinal tract, so that the systemic intake is relatively low. Due to the very small concentration of ivermectin, a selective and sensitive approach is needed for the analysis of ivermectin in blood. Several methods have been developed using plasma and Dried Blood Spots, but there are still shortcomings due to hematocrit effects. Therefore, this study was conducted to establish a validated ivermectin analysis method with doramectin as the internal standard in using Ultra High-Performance Liquid Chromatography-Tandem Mass Spectrometry. MethodsMass spectrometry equipped with triple quadrupole and positive electrospray ionization mode was used to conduct the analysis. For the biological matrix, whole blood was used by Volumetric Absorptive Microsampling and extracted using a protein precipitation technique with a combination of acetonitrile and methanol (1:1). VAMS has some advantages such as not being affected by hematocrit, requires a small and fixed volume of sample, also a more efficient sampling process. ResultsThe optimum conditions were achieved with an Acquity® UPLC BEH C18 column (1,7 μm; 2.1 × 100 mm); extracted-flow rate was 0,2 mL/min; mobile phase was 5 mM ammonium formate pH 3.00 and acetonitrile (10:90) with isocratic elution. Multiple Reaction Monitoring (MRM) detection by m/z values was 892.41 > 569.5 for ivermectin and 916,41 > 331,35 for doramectin. ConclusionThe method has been appropriately validated in compliance with the 2018 guidelines laid out by the US Food and Drug Administration. Resulting the minimum detection (LLOQ) was 1 ng/mL with a linear concentration range spanning from 1 to 150 ng/mL.

The role of fines in espresso extraction dynamics

The impact of particle size distribution of coffee grounds on espresso extraction was explored. Finely ground coffee for espresso has a characteristically bimodal particle size distribution. For a given median grind size, different grinding technologies can yield a different share of fines (particles < 100 µm). We performed espresso extractions for a range of median particle sizes and systematically varying the share of fines by adding sieved fines to the coffee grounds. Dynamic beverage weights, extraction percentage, extraction time and dynamic headspace PTR-MS (proton-transfer mass spectrometer) analysis and sensory evaluation of the resulting brews were measured. We show that the share of fines plays a key role in the espresso extraction flow rate. An increase of share of fines decreases coffee bed permeability, leads to reduced flow rates and longer extraction times. A statistical model using partial least squares regression of the particle size distributions of coffee grounds confirms that fines decrease the coffee bed permeability. The PTR-MS analysis shows a non-linear increase of aroma compounds in the cup with increasing extraction yield. Our hypothesis is that both extraction efficiency and post-extraction evaporative losses of aroma compounds influence the final aroma compound concentrations in the cup.

Semi-automated filter micro-solid phase extraction based on urea-formaldehyde microsphere followed by corona discharge-ion mobility spectrometry for simultaneous detection of fentanyl and nor-fentanyl in urine

In this work, semi-automated filter micro-solid phase extraction (SA-FμSPE) packed by urea–formaldehyde (UF) microspheres coupled with corona discharge ionization-ion mobility spectrometry (CD-IMS) was developed for the extraction and determination of fentanyl and nor-fentanyl in urine samples. UF microspheres, synthesized by aqueous polymerization, can be used to achieve effective extraction of analytes through multiple adsorption interactions such as hydrophobic, dipole–dipole and hydrogen bonding interactions. UF microspheres dispersed in methanol were packed in the filter by syringe, and the extraction process was performed by a portable automatic filter extraction device. The parameters affecting extraction efficiency (i.e., extraction time, the flow rate of extraction, pH value, amount of sorbent, ionic strength, cycle times of desorption, and type of eluent) were investigated. Then, the eluate containing fentanyl and nor-fentanyl was simultaneously analyzed by CD-IMS in positive mode. Under the optimal extraction conditions, the detection limits for the target compounds were 5.00 ng mL−1 and 8.00 ng mL−1, respectively. The spiked recoveries were in the range of 81.97 % −112.37 % by testing the real samples and validated by UHPLC-MS. Thus, the satisfactory results reveal that SA-FμSPE coupled with CD-IMS has great potential for on-site extraction and detection of fentanyl and nor-fentanyl in urine samples.

4E analysis and parameter study of a solar-thermochemical energy storage CCHP system

The combination of calcium looping and concentrating solar power (CSP) is a promising energy conversion technology that can greatly increase the share of solar energy used in combined cooling, heating and power (CCHP) systems. This paper designs a CCHP system based on solar energy and thermochemical energy storage. The system runs all day through day and night modes. Under basic working conditions, the energy and exergy efficiencies of the system could reach 56.92 % and 35.94 %, respectively. The system is evaluated by multiple approaches including parametric sensitivity analysis and 4E (energy, exergy, economy and environment)) analyses. The results demonstrate that the system could produce 2618.09 MW of electricity, 305.56 MW of heat and 523.88 MW of cooling capacity per day, respectively. At the same time, the reductions of CO2 emissions and fossil fuel consumption could reach 2222.76 tons and 696.41 m3 per day, respectively. Furthermore, the increasing mass flow of main turbine inlet could increase both the system efficiency and the exergy efficiency. Thus, it is beneficial to reduce the environmental impact but with the increasing investment cost. In the meanwhile, the exergoeconomic factor and exergoenvironment factor of the system were 55.65 % and 0.139, respectively. Besides, as the extraction flow rate of the intermediate pressure turbine increases, the energy efficiency increases but the exergy efficiency descends. This is unfavorable to reducing the environmental impact, yet it could decrease the investment cost of the system. These results reveal that the hybrid system has the characteristics of high efficiency and emission reduction in energy storage, power generation, heating and cooling, and has great development potential.

Physicochemical Properties Research of Mechanoactivated Flour from Wheat Germ Cake

In today’s accelerating world, the concept of waste-free production, based on the maximum utilization of all resources, becomes relevant. To increase the use efficiency of materials obtained as a result of grain processing, a man developed an integrated approach implying a disintegrator. The research aim is to study the mechanical activation process impact of flour from wheat germ cake (FWGC) on its physico-chemical properties. The authors revealed the rational mode of the grinding process: the rotation speed of the rotors is 10,500 rpm, the impact velocity is 175 m/s, the process duration is 180 sec, providing a weighted average particle size of the final mechanical powder of 52 microns with maximum bulk density parameters of 760 kg/m3 and water absorption capacity of 70 %. During mechanical activation, the chemical composition of FWGC changes: the mass fraction of proteins increases by 1.8 %, simple sugars – by 17 %, ash content – by 11 %, starch content decreases by 8 % compared to the FWGC obtained without mechanical activation. To determine the physico-chemical composition of the aqueous extract of the FWGC, a man run the microfiltration parameters selection: the aqueous extract flow rate of the FWGC over the membrane surface is not less than 1.0–1.2 m/s; the working pressure of the process is within 0.25 MPa; the extract temperature does not exceed (25 ± 5)°C. According to the microfiltration separation process research results of the aqueous FWGC extract, the mechanical activation increases the low-molecular-weight proteins proportion in flour, indicating a growth in its bioavailability and digestibility.

Electrodeposited histidine-(CuCr)layered double hydroxides/carbon dots for in-tube solid-phase microextraction of chlorophenols from water, juice, and honey samples followed by HPLC-UV

A novel adsorbent consisting of a composition of carbon dots and CuCr-layered double hydroxides intercalated with l-histidine (C-dots@His/LDHs) was introduced. This adsorbent was electrochemically deposited on the inner surface of a capillary copper tube. It was used as an adsorbent for in-tube solid-phase microextraction of chlorophenols (CPs). Separation and measurement of CPs were done by high-performance liquid chromatography-ultraviolet detector. The main parameters which had the most impact on the extraction efficiency and time such as extraction time and flow rate, desorption time and flow rate, ionic strength (salt concentration) and pH were optimized. Calibration curves (0.5–1000 μg L−1) were plotted in real sample (tap water) under optimal conditions which coefficients of determination better than 0.9893 and relative recoveries in the range of 88–120 % were obtained. The limits of detection (S/N = 3) and limits of quantification (S/N = 10) were obtained in the range of 0.1–1.0 μg L−1 and 0.3–3.0 μg L−1, respectively. The intra- and inter-assay precisions (RSD%, n = 3) were better than 5.9 and 8.8 %, respectively.

Electrospun mesh pattern of polyvinyl alcohol/zirconium-based metal-organic framework nanocomposite as a sorbent for extraction of phthalate esters

Herein, an electrospun composite polyvinyl alcohol/zirconium-based metal-organic frameworks (PVA@UiO-66) nanofiber coating was prepared on the surface of stainless steel mesh (SSM) and then utilized as novel sorbent for the extraction of phthalate esters (PEs) in milk and water samples. Gas chromatography equipped with a flame ionization detector (GC–FID) was used for the quantitative determination of extracted analytes. The SSM coated with PVA@UiO-66 was used in a polypropylene syringe to fabricate the solid-phase extraction (SPE) device. The PVA@UiO-66 nanofiber coating was confirmed using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy analysis (FT–IR), and field emission scanning electron microscopy (FESEM). The effective parameters of the extraction efficiency including volume and type of desorption solvent, sample volume, ionic strength, pH, extraction flow rate, and desorption flow rate were optimized. At the optimal extraction conditions, the calibration plots for phthalate esters were linear within the range of 0.05–100 ng mL−1 and, low detection limits (0.015–0.06 ng mL−1). Finally, this semi-automated SPE was used for the extraction and detection of phthalate esters (PEs) in milk and various environmental real water samples. The results showed good precision with acceptable and satisfactory extraction recovery values ranging from 89.5 to 99.2% and relative standard deviations (RSDs%) ranging from 4.5 to 6.9%.

MXene nanosheets woven in polyacrylonitrile nanofiber yarns aligned spider web as a highly efficient sorbent for in-tube solid phase microextraction of beta-blockers from biofluids

The use of electrospinning has received much attention in the production of nanofiber webs due to its advantages such as flexibility and simplicity. The direct electrospinning of nanofibers in an aligned or twisted form and the production of nanofiber yarns can turn nanofibers into woven fabrics, which leads to an increase in the diversity of nanofiber applications and improves their end-use possibilities. In this work, a victorious nanofiber yarn spinning system was used with the help of a rotating funnel. Yarn formation was studied using a composited polyacrylonitrile (PAN)/MXene polymer solution ejected from two oppositely charged nozzles. Finaly their application for packed-in-tube solid-phase microextraction of β-blocker drugs from biofluids was demonstrated. The separation and quantification of analytes were performed by HPLC-UV instrument. The 3D-yarn PAN/MXene sorbent exhibited high flexibility, porosity, sorbent loading, mechanical stability, and a long lifetime. The characterization of the final nanofiber was carried out utilizing Fourier-transform infrared spectroscopy, field emission scanning electron microscope, energy-dispersive X-ray mapping, transmission electron microscope and X-ray diffraction analysis. Various parameters that affect the extraction efficiency, such as extraction time, pH, ionic strength and flow rate of sample solution, and type, volume and flow rate of eluent, were investigated and optimized. Under optimized conditions, the limits of detection were obtained in the range of 1.5–3.0 μg L−1. This method demonstrated appropriate linearity for β-blockers in the range of 5.0–1000.0 μg L−1, with coefficients of determination greater than 0.990. The inter- and intra-assay precisions (RSDs, for n = 3) are in the range of 2.5–3.5%, and 4.5–5.2%, respectively. Finally, the validated method was put in an application for the analysis of atenolol, propranolol and betaxolol in human urine and saliva samples at different hours and acceptable relative recoveries were obtained in the range of 89.5% to 110.4%.

A numerical simulation of thermally-enhanced soil vapor extraction with a validation of an actual contaminated site

Thermally-enhanced soil vapor extraction (T-SVE) remediation technology is widely used in organic-contaminated sites due to its high efficiency, short remediation period and controllable secondary contamination. However, the remediation efficiency is affected by the complex site factors, which leads to the uncertainty of the remediation process and energy waste. Thus, it is necessary to optimize T-SVE systems to accurately remediate the sites. In this work, a pilot site of reagent factory in Tianjin was taken as the research object to validate the model, and the T-SVE process parameters of a VOCs-contaminated sites were predicted by this simulation method. The simulation results showed that the Nash efficiency coefficient E of the measured and simulated temperature rise data in the study area was 0.885, and the linear correlation coefficient R of the measured and simulated concentrations of cis-1,2-dichloroethylene after remediation was 0.877, indicating that this simulation method is highly reliable. Based on this numerical simulation method, some parameters of the T-SVE process at the VOCs-contaminated site of an insulation plant in Harbin were simulated and optimized. Included a heating well spacing of 3.0 m, extraction pressure of 40 Kpa, extraction well influence radius of 4.35 m, extraction flow rate of 2.97 × 10-4 m3/s, and a theoretical number of 25 extraction wells (adjusted to 29 wells in practice), and the corresponding extraction well layout has been designed. The results can provide a technical reference for the future application of T-SVE in the remediation of organic-contaminated sites.

Generation of Spherical Microparticles of Moringa Leaves through a Supercritical Antisolvent Extraction Process

The objective of this work was evaluation of the supercritical antisolvent extraction (SAE) process to generate microparticles with antioxidant activity from Moringa leaves. A biodegradable polymer was used as an inductor of particle precipitation. An ethanolic extract of 25 mg/mL was used in the SAE process, during which the influences of pressure (100–200 bar), temperature (35–55 °C) and extract–polymer ratio (0.11–0.33) on particle size and antioxidant activity were evaluated. An extract flow rate of 3 mL/min, a supercritical CO2 (scCO2) flow rate of 30 g CO2/min and a nozzle diameter of 100 µm were kept constant. The identification of several compounds of Moringa leaves, namely, coumaric acid and quercetin 3D glucoside, were determined with ultra-performance liquid chromatography coupled with mass spectrometry. The antioxidant activity of the extract and the precipitates was measured with 2,2-Diphenyl-1-picrylhydrazyl. Spherical microparticles with diameters in the range of 2–5 µm were obtained, with moderate antioxidant activity.

Heat load-carrying capacity of surface water source combined with stagnant water and river water

This paper studies the heat load-carrying capacity characteristics of a surface water body integrated with stagnant water and river water as a heat source for water source heat pumps in winter. In the cold climate, the influence of each variable on the surface water temperature was simulated and analyzed. The results showed that the solar radiation intensity, the air temperature at the water surface and the heat pump extraction time are important factors affecting the heat load-carrying capacity of surface water body. At a simulated solar radiation intensity of 500 W/m2, the water body provided the heat pump with 25 kg/s of extracted water to keep the surface water body temperature largely stable. The heat pump extraction time affects the water extraction flow rate. The flow rate for 24 h of heat extraction per day was only 0.4 times that of 10 h of heat extraction. The replenishment flow rate can change the rate of water temperature variation and the heat load-carrying capacity of the water body. When the solar radiation intensity was 0W/m2, the average temperature drop of the water body decreased from 0.23 °C to 0.15 °C by increasing the replenishment water flow rate from 0 to 10 kg/s.

The elimination of arsenic from natural gas condensate via pulse sieve-plate column: Experimental and application of DFT for chemical structure

This work focuses on the elimination of arsenic ions from natural gas condensate via pulse sieve-plate column. The extraction of arsenic ions using the extractants: hydrochloric acid (HCl), Methanol (MeOH) and HCl/MeOH are investigated via density functional theory (DFT). The DFT method clearly demonstrates the synergistic reaction mechanism of the extractant HCl/MeOH, providing an improved extraction effect greater than the use of single extractants. Applying optimal conditions: MeOH (5 M), HCl (1 M), feed flowrate (55 ml/min), extractant flowrate (220 ml/min) and pulse velocity (2 cm/s), it is found that the pulse sieve-plate column leads to an increase in extraction of triphenylarsine. Mass-transfer parameters, including the Sauter mean diameter: 1.917 mm, the axial dispersion coefficient of the continuous phase: 0.012 m2/s, the extract percentage: 94.55%, the overall mass transfer coefficient: 1.228x10-3 s−1 as well as height of a transfer unit (HTU): 22.92 cm are also calculated under optimal conditions.

Research on Gas Control Technology of “U+ Omni-Directional Roof to Large-Diameter High-Level Drilling Hole” at the End Mining Face of Multi-Source Goaf

Aiming at the gas over-run problem in the upper corner of the “U-type ventilation” end-mining working face in the multi-source goaf of the #15 coal seam in the Phoenix Mountain Mine, site survey and numerical simulation methods were adopted, which showed that the maximum caving zone height of the #15 coal seam is 14.87 m, and the maximum height of the fissure zone is 51.63 m. On this basis, the gas control scheme of the “U+ omni-directional large-diameter high-level borehole along roof strike” in the end-mining working face was formulated. After adopting this scheme, the extracted gas concentration of each borehole will reach 5–20%, the gas extraction flow rate will reach 1 m3/min–2.5 m3/min, the gas concentration at the upper corner of the working face will be controlled below 0.54%, and the gas concentration in the return airway will be controlled below 0.35%, achieving the expected effect of gas control.

Orthogonal Experimental Study on Remediation of Ethylbenzene Contaminated Soil by SVE

Soil vapor extraction (SVE) technology has strong potential value in the decontamination of soils dominated by volatile contaminants. In this paper, in order to evaluate in detail the influence of the main factors on the efficiency of SVE, L9(34) orthogonal tests and response surface analysis were carried out using a self-developed one-dimensional SVE system model. A first-order kinetic reaction model was also employed to analyze the relationship between pollutant concentration and time. The thermal reaction unit of SVE technology with a scale consistent with the soil column of the indoor test was simulated using COMSOL simulation software. The obtained results indicate that the most important factors affecting the performance of SVE are time, temperature, and contaminant concentration, while the influence of the extraction flow rate is not significant. A first-order kinetic reaction model can be used to predict the half-life of contaminant concentrations. Combined with the desirability function, the optimal conditions for the removal of ethylbenzene from soil were: time 180 min, temperature 20 °C, extraction flow 6000 mL/min, and contaminant concentration 2%. The developed numerical model, 3D-SVE, nicely simulates laboratory findings. These results can provide ideas to improve the efficiency of SVE.

Evaluation of a septumless mini-cartridge for automated solid-phase extraction cleanup in gas chromatographic analysis of >250 pesticides and environmental contaminants in fatty and nonfatty foods

The QuEChERSER mega-method has recently been introduced to quantify and identify a wide range of chemical residues (pesticides, veterinary drugs, environmental contaminants, among others) in nearly all types of foods. The approach calls for taking a small amount of the initial extract to cover analytes amenable to liquid chromatography, and the remainder is salted out for analysis by gas chromatography (GC), both with mass spectrometry (MS) based detection. In the case of GC-MS(/MS), the extract undergoes automated robotic mini-cartridge solid-phase extraction (SPE) cleanup in a technique known as µSPE or instrument-top sample preparation (ITSP). In 2022, a septumless mini-cartridge for µSPE was introduced to improve upon the ITSP design. The new design houses a bed of 20 mg anhydrous MgSO4, 12 mg each of C18 and primary secondary amine sorbents, and 1 mg of graphitized carbon black, the latter substituting for CarbonX used in the ITSP product. The septumless µSPE mini-cartridge employs a different gripping mechanism with the syringe needle that allows leak-free operation at higher flow rates (e.g. 10 µL/s), whereas the ITSP design is limited to 2 µL/s. Based on cleanup and analyte elution profiles, the extract load volume and flow rate was increased in µSPE for QuEChERSER from 300 µL at 2 µL/s to 500 µL at 5 µL/s, which improved accuracy of results, sped the cleanup step, and obviated the need for micro-vial inserts in the receiving vials. The new design also reduced both the amount and consistency of dead (void) volumes in the mini-cartridges from 83 ± 14 µL to 52 ± 7 µL for 200-600 µL load volumes. Normalization of peak areas to internal standards led to recoveries between 80 and 120% with typical RSDs <5% in low-pressure GC-MS/MS of 227-242 out of 252 pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, and polycyclic aromatic hydrocarbons in hemp powder, spinach, whole milk, egg, avocado, and lamb meat.

Screening for α-Glucosidase-Inhibiting Saponins from Pressurized Hot Water Extracts of Quinoa Husks.

The present study extracted total saponins from quinoa husks with pressurized hot water extraction and optimized the extraction conditions. The response surface methodology (RSM) with a Box–Behnken design (BBD) was employed to investigate the effects of extraction flow rate, extraction temperature and extraction time on the extraction yield of total saponins. A maximal yield of 23.06 mg/g was obtained at conditions of 2 mL/min, 210 °C and 50 min. The constituents of the extracts were analyzed by liquid chromatography–mass spectrometry (LC-MS). A total of twenty-three compounds were identified, including five flavonoids, seventeen triterpenoid saponins and a phenolic acid. Moreover, we performed an in vitro assay for the α-glucosidase activity and found a stronger inhibitory effect of the quinoa husk extracts than acarbose, suggesting its potential to be developed into functional products with hypoglycemic effect. Finally, our molecular docking analyses indicated triterpenoid saponins as the main bioactive components.

Research and Application of "Concentric Ring" Reinforcement and Sealing Technology for Gas Drainage Boreholes in Soft-Coal Seams.

The problems of lack of stability and difficult sealing of gas drainage boreholes in soft-coal seams directly affect the efficient extraction of gas in these soft-coal seams. After the holes are drilled, the collapsed holes lead to the failure to seal in time, which brings hidden dangers to mine production and causes time and economic waste. In this paper, the viscoelastic mechanics model is used to solve the force of the coal body in the fractured area of the orifice, combined with the theory of the external conditions affecting the collapse of the orifice of the soft-coal seam. The reason for the easy collapse of the borehole of the soft-coal seam is studied, and a reasonable solution is proposed. “Concentric ring” reinforced sealing technology, elaborated from the physical model, technical principles, and processes, was finally carried out in an on-site application test at the N2106 working face of a mining area in Shanxi. The results show that the fracture zone of the soft-coal seam easily enters a stage of rapid deformation under the effect of time. Its strong adsorption behavior, easy expansion, and other characteristics, combined with the violent disturbance of the drill pipe when the drilling is offset, eventually cause the hole to retreat, making it easy to deform and collapse afterward. The test boreholes reinforced and sealed with “concentric rings” have no problem of collapsed holes after retreating. The gas concentration remained above 30% in the first 30 days. The maximum gas purity of the borehole on the 30th day of extraction flow rate reached 0.053 m3/min. It is found that the sealing effect of the “concentric ring” reinforced seal drilling technology is better than that of the traditional sealing technology.