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An optimization method of fracturing fluid volume strength was introduced taking well X-1 in Biyang Sag of Nanxiang Basin as an example. The characteristic curves of capillary pressure and relative permeability were obtained from history matching between forced imbibition experimental data and core-scale reservoir simulation results and taken into a large scale reservoir model to mimic the forced imbibition behavior during the well shut-in period after fracturing. The optimization of the stimulated reservoir volume (SRV) fracturing fluid volume strength should meet the requirements of estimated ultimate recovery (EUR), increased oil recovery by forced imbibition and enhancement of formation pressure and the fluid volume strength of fracturing fluid should be controlled around a critical value to avoid either insufficiency of imbibition displacement caused by insufficient fluid amount or increase of costs and potential formation damage caused by excessive fluid amount. Reservoir simulation results showed that SRV fracturing fluid volume strength positively correlated with single-well EUR and an optimal fluid volume strength existed, above which the single-well EUR increase rate kept decreasing. An optimized increase of SRV fracturing fluid volume and shut-in time would effectively increase the formation pressure and enhance well production. Field test results of well X-1 proved the practicality of established optimization method of SRV fracturing fluid volume strength on significant enhancement of shale oil well production.

High-quality lacustrine shale beds within the Paleogene Hetaoyuan Formation in the Biyang Sag, Nanxiang Basin, exhibit significant potential for shale oil resources. Previous studies on the oil-bearing potential and hydrocarbon occurrence of shales in the Biyang Sag were relatively limited, potentially hindering advancements for shale oil exploration. This study focuses on the shales found in the third sub-member of the third member within the Hetaoyuan Formation in well Y1, which locates in the southern area of the Biyang Sag. Through various geochemical analyses such as Rock-Eval pyrolysis, multi-temperature pyrolysis and X-ray diffraction, this research systematically investigates the shale oil contents, hydrocarbon occurrence characteristics, and influencing factors. These results indicate that the lithofacies assemblages of the shale primarily consist of felsic shale facies, dolomitic shale facies and mixed shale facies, with a well-developed laminar structure. The source rock quality is classified as good to excellent, and the thermal maturity stage of oil window. The predominant organic maceral is sapropelic, with organic matter types ranging from Ⅰ to Ⅱ1. Oil content increases with burial depth, ranged from adsorbed hydrocarbons in the upper section to free hydrocarbons in the lower section. Detrital mineral content and total organic carbon (TOC) content are identified as the main factors influencing free and adsorbed hydrocarbon content, respectively. Overall, the oil saturation index (OSI) of the shale in the lower section of the Hetaoyuan Formation exceeds 100 mg/g, with an average free hydrocarbon content over 3 mg/g, indicating promising prospects for shale oil exploration and development.

[Objective] In order to reduce the impact of high-speed maglev harmonics on traction network, and to ensure the normal operation of high-speed maglev trains, it is necessary to study the harmonic characteristics of the high-speed maglev traction power suppl system, and the corresponding harmonic suppression methods. [Method] The composition of the high-speed maglev traction power supply system is studied, the dual three-phase half-controlled 12-pulse multiple rectifier circuit and its harmonics are theoretically analyzed and simulated. Based on the principle of the Adaline neural network algorithm and the harmonic characteristics of high-speed maglev trains, a high-speed maglev harmonic detection model based on Adaline is constructed. A harmonic compensation control strategy is used to generate compensating signal of current with equal magnitude but opposite direction to the detected harmonics, for harmonic suppression of the system distorted currents. [Result & Conclusion] Simulation results indicate that before adopting the harmonic detection and suppression method based on Adaline algorithm, the harmonic distortion rate is 11.16%. After applying this method, the content of each harmonic decreases significantly, and the harmonic distortion rate decreases to 1.41%. The research results demonstrate that the proposed harmonic detection and suppression method can effectively reduce harmonic distortion, thereby improving the stability and operational efficiency of the traction power supply system.

This is an essay in the field of metallurgical engineering. Taking a lithium mica ore in Jiangxi as raw material, the roasting-leaching, mixed acid ripening, direct acid leaching and alkali pressure cooking process were explored. Finally, the sulfate roasting-water leaching method was used to extract lithium from lithium mica ore. At the same time, the effects of roasting temperature, roasting time, additive type, additive amount, liquid-solid ratio and leaching temperature on lithium leaching rate were studied. The results show that roasting temperature has a great influence on lithium leaching rate, and the leaching effect of lithium is better in the appropriate roasting temperature range. 40% potassium sulfate, 20% sodium sulfate and 20% calcium oxide were added to the lithium mica ore, calcinated at 900 ℃ for 1 h, and the calcine was leached at room temperature for 1 h according to the liquid-solid ratio of 1∶1. The lithium leaching rate reached 94.87%. This shows that the effect of using sulfate as an additive to roast and extract lithium is better. Through the study of the roasting mechanism, it can be seen that the mineral structure is reconstructed after the addition of sulfate after high temperature roasting. The sodium and potassium ions in the ore are replaced with lithium ions in the lithium mica, so that they are separated from the insoluble aluminum silicate minerals to generate soluble lithium sulfate, which is then immersed in water and then into the solution.

Based on rock mineral and geochemical analysis, microscopic observation, physical property measurement, and thin laminae separation test, etc., the characteristics of typical laminae of the Paleogene Shahejie Formation carbonate-rich shale in the Jiyang Depression were analyzed, and the organic matter abundance, reservoir properties, and oil-bearing properties of different laminae were compared. Typical shale reservoir-flow structures were classified, and the mobility of oil in different types of shale reservoir-flow structure was compared. The results show that the repeated superposition of mud laminae and calcite laminae are the main layer structure of carbonate-rich shales. The calcite laminae are divided into micritic calcite laminae, sparry calcite laminae and fibrous calcite vein. The mud-rich laminae are the main contributor to the organic matter abundance and porosity of shale, with the best hydrocarbon generation potential, reservoir capacity, and oil-bearing property. The micritic calcite laminae also have relatively good hydrocarbon generation potential, reservoir capacity and oil-bearing property. The sparry calcite laminae and fibrous calcite vein have good permeability and conductivity. Four types of shale reservoir-flow structure are developed in the carbonate-rich shale, and the mobility of oil in each type of reservoir-flow structure is in descending order: sparry calcite laminae enriched shale reservoir-flow structure, mixed calcite laminae enriched shale reservoir-flow structure, fibrous calcite vein enriched shale reservoir-flow structure, and micritic calcite laminae enriched shale reservoir-flow structure. The exploration targets of carbonate-rich shale in the Jiyang Depression Shahejie Formation are different in terms of reservoir-flow structure at different thermal evolution stages.

In order to explore the influence of the seepage of the leftover water sump in the open pit on the mining stability of the mine roadway after the coal mine is converted from open pit mining to underground mining, taking Pingzhuang West Open pit Mine in Inner Mongolia as the research background, the two wing water silos and mine workings are modeled by using FLAC numerical simulation software. On this basis, the points for attention and improvement measures in the mining process of the two wing roadway are proposed. The numerical results show that the maximum plastic pressure of the roadway is concentrated at the bottom of the roadway under two working conditions; the displacement deformation plastic zone is not connected, and the tunnel has no overall plastic connection failure and water permeability failure under the influence of seepage; under the condition of extreme water level, the seepage flow at the bottom of both wings of the roadway increases obviously, but the maximum seepage flow meets the specification requirements; due to the time effect, the strength of the surrounding rock of the roadway decreases and long-term creep deformation will occur at the same time. Therefore, waterproof and drainage measures should be taken for the pit bottom and pool.

For the problem of stick-slip vibration caused by hard rock formation in the process of drill bit penetrating in coal mine, and the discrete element method (DEM) was employed to study the rock cutting performance and stick-slip vibration behavior of PDC bit drilling in five typical different hardness rock strata. The result shows that the stick-slip phenomenon of the bit is more obvious with the increasing of the formation hardness, and in the ultra-hard rock layer, it slips on the rock surface and cannot be effectively drilled. The approach of increasing the rotational speed of the bit can weaken the stick-slip behavior to an extent, but it has no obvious effect on improving the drilling efficiency. The drilling performance of the bit can be improved by increasing drilling pressure, but it will also lead to more serious stick-slip vibration. The torsional impact method can effectively weaken or even inhibit the stick-slip vibration of the bit and improve the drilling performance. However, excessive torsional impact force will lead to an increase in the impact load on the bit.

Liquidambar formosana is an excellent landscape ecological tree species because its beautiful tree shape and red or orange leaves in autumn. In order to understand the genetic basis of discoloration and secondary metabolism of L. formosana leaves, the mixed samples of L. formosana leaves in five leaf discoloration stages were used for full-length transcriptome sequencing using single-molecule real-time sequencing technology (PacBio platform). The results were as follows: (1) High-quality 41.04 Gb data were obtained by full-length transcriptome sequencing, from which 563 180 full-length non-chimeric sequences were identified, and 27 269 high-quality full-length transcripts were obtained by clustering and de-redundancy. In 27 269 full-length transcripts, 2 035 long-chain non-coding RNA (lncRNA) were predicted, and 14 892 simple sequence repeat (SSR) sites and 1 856 transcription factors were detected. (2) The results of gene annotation showed that a total of 24 857 transcripts were annotated in eight databases such as NR, GO, COG and KEGG, etc., 124 metabolic pathways were obtained in KEGG database, including ribosome, carbon metabolism, amino acid biosynthesis and so on, and 49 and 71 transcripts were involved in flavonoid and chlorophyll metabolism respectively. The above results preliminarily reveal the transcriptome information and functional characteristics of L. formosana leaves during the leaf discoloration stage, and provide basic data for the follow-up study of the molecular mechanism of leaf discoloration, the pathway and regulation of pigment metabolism and synthesis, the cloning of related functional genes and the improvement of leaf color.

【Objective】The effects of combined application of chemical fertilizer and biochar on the yield, quality, and main chemical components of flue-cured tobacco were discussed to provide a theoretical basis for the chemical fertilizer reduction application.【Method】Tobacco variety Yunyan 85 was taken as the test material, five treatments of chemical fertilizer and biochar were set up, CK (control): conventional fertilizer; T1: conventional fertilizer+180 kg/hm2 biochars; T2: conventional fertilizer+360 kg/hm2 biochars; T3: 80% base chemical fertilizer+180 kg/hm2 biochars; T3: 80% base chemical fertilizer+360 kg/hm2 biochars. Three repeated randomized block experiments were used in the field. Representative tobacco plants were selected to measure their agronomic traits and SPAD value after transplanting 63 d (topping stage). After curing, the yield and output value of flue-cured tobacco in each treatment were investigated, the main chemical components and sensory quality evaluation were analyzed.【Result】Application biochar promoted the growth and development of flue-cured tobacco, and significantly increased the plant height, maximum leaf area, and stem girth. Chemical fertilizer reduction combined with biochar were not significantly reduced the plant height, maximum leaf area, and stem girth, but the SPAD values in the middle leaves were significantly lower. The yield and output value of treatments were T2>T4>T3>T1>CK. The exorbitant value of soil C/N ratio was beneficial for improving the yield and output value of flue-cured tobacco.The content of total sugar and reducing sugar in tobacco leaves under all treatments with over 26% and 22%, respectively, exceeded the standard of high quality tobacco leaf, and the content of total nitrogen, nicotine, potassium, nitrogen-nicotine ratio and potassium-chloride ratio were all within the appropriate range, respectively. Tabcco leaves under the T1 and CK treatments had more harmonious chemical components. With increasing soil C/N ratio value, contents of total sugar, reducing sugar and potassium of flue-cured tobacco were increased, but decreased the contents of total nitrogen and nicotine. A suitable amount of application biochar resulted in coordination of tabacco leaf chemical components. However, excessive application biochar reduced quality of tobacco leaves. The sensory quality scores in T1 treatment were the higher (66.10), then in CK and T3 treatments (61.11), and the lowest in T2 treatment (59.86).【Conclusion】The combined application chemical fertilizer and biochar has important effects on the agronomic, economic and quality traits of flue-cured Tobacco. The higher values of soil C/N ratio (T1 and T3 treatments) were good for improving the quality of tobacco leaves, while the exorbitant values of soil C/N ratio (T2 and T4 treatments) were conducive to improving the yield and output value of tobacco leaves. Considering the application fertilizer effects, it was suggested that the best fertilizer application was the combination of biochar fertilizer of 180 kg/hm2 and conventional fertilizer in Sichuan Mianning tobacco-planting area.

Purposes Propylene is an important olefin raw material, and the removal of propane impurities in it is very important in actual production. Metal-organic frameworks (MOFs) have great prospects for the separation and purification of propane/propylene. Among them, propane-selective adsorbents can be used to obtain high-purity propylene products in one step, which has extremely high industrial value. MIL-126(Fe) has great potential for preferential adsorption of alkanes becaused of the abundant low-polarity benzene rings that provide dense electronegativity binding sites. Methods MIL-126(Fe) was synthesized through solvothermal method. Findings The stability, C3H8/C3H6 adsorption, and separation properties of MIL-126(Fe) were studied. The results showed that MIL-126(Fe) had excellent stability. The adsorption capacity of C3H8 at 298 K and 1 bar was 185.37 cm3/g, which was higher than that of most propane-selective adsorption MOFs. The IAST selectivity for C3H8/C3H6 mixture was 1.44 at 0.1 bar and 1.23 at 1 bar. It is showed that MIL-126(Fe) had reverse adsorption on propane-propylene mixture, and its propylene recovery potential was 19.71 cm3/g, which was close to the highest level of domestic and international researches. Conclusions The results of gas breakthrough experiments showed that MIL-126(Fe) has great potential for industrial application in one-step production of high-purity propylene.

With the development of urban engineering construction, the issue of construction engineering accidents has become more and more prominent. The geotechnical parameter interval obtained by using the traditional methods cannot meet the needs of actual engineering. Based on the idea of unsupervised learning, the peaty soil with the worst engineering properties is considered, and 8 physical indexes are selected as the input set. The principal component analysis (PCA) algorithm is used to realize the dimensionality reduction of multi-sample and multi-parameter decoupling, and the correlation and sensitivity of each physical index is obtained. Combined with its correlation and sensitivity, the comprehensive evaluation value of physical indexes of peat soil with different buried depths is given. The k-means clustering is used to analyze the relationship among physical index, and comprehensive evaluation value and engineering characteristics of peaty soil provide a theoretical basis for the selection of geotechnical parameters. The supervised learning method-BP neural network algorithm is used to analyze the unsupervised results and verify the accuracy of the (PCA—k-means) algorithm model. The normal samples obtained by clustering analysis are optimized by a variety of truncation methods to obtain a reliable value range, and the value results are compared with the actual engineering values to verify the rationality of the model engineering parameters. The algorithm model is of good engineering application value. The research results can provide references for engineering investigation, design and construction parameter values, and also provide a new analysis method for geotechnical parameter value analyses.

The polar cap patch is a common ionospheric structure. It often appears in the F region of the ionosphere over the polar caps; these patches are usually characterized by electron densities that can be even twice greater than that of the surrounding area. Untangling the formation and evolution of the polar cap patch can unveil the transportation of energy and momentum through magnetosphere-ionosphere-thermosphere couplings. However, owing to their wide horizontal reach (~100～1000 km), these high electron density structures greatly obstruct radio wave propagation over the polar cap, particularly at their edges, seriously impeding efforts tied to communication, navigation, and positioning. Therefore, the study of polar cap patches is not only of significance within space physics but also of great value within the context of space weather monitoring and prediction. In this paper, recent progress in polar cap patch research is summarily reviewed. The focus of our review includes the possible mechanisms underlying the formation of the dominant dayside reconnection; the recently proposed sunward return flows, likely produced by the nightside reconnection or other processes; and the newly defined patch-polar cap hot patch and its dependencies on various factors (e.g., solar & geomagnetic activities, local plasma transport, and particle precipitation). We will also delve into patch occurrences, as they relate to spatiotemporal dynamics as well as the interplanetary magnetic field conditions. We will also comprehensively review the evolutionary process tied to the Dungey convection cycle, as it moves from the dayside to the nightside and finally as it exits the polar caps, initially modulated by the pulsed nightside reconnection and then sunward transportation by the return flow. Lastly, we will detail the effects of ion upflow and ionospheric scintillation associated with the polar cap patch. For each subject, we will provide a detailed account of progress that has been made and its corresponding prospects.

Based on the research background of Shandong Lilou Coal Mine, this paper used methods such as on-site investigation, engineering comparison, and on-site monitoring to research on the high-energy events that have occurred in Lilou Coal Mine since 2020, and drew the following conclusions: ①Systematically analyzed the relationship between four influencing factors and high-energy microseismic events including the distribution of abutment pressure, working face “square”, crossing faults, and mining speed, and searched the causes of large energy events. The mining influence range of No.1302 (top) working face is about 30 m behind the face to 170 m in front, and the advanced stress peak is about 70 m in front. The lateral microseismic events are mainly distributed along the gob-side entry, and the whole is offset to the side of the goaf. The distribution of microseismic events at No.1303 working face in the advancing direction of the working face ranges from 15 m behind the face to 200 m in front of the face, and the advanced stress peak is about 80 m in front of the face. The microseismic event at the No.1303 working face is bimodal in the lateral distribution pattern, shifting to the belt grooves. Affected by the wide coal pillar, the stress concentration on the belt grooves is higher than that on the track tunnel. The frequency and energy of microseismic events gradually increased before the “square” of the work face, and stabilized after the “square”. Before crossing the fault, the microseismic events gradually increased, decreased sharply during the crossing, and gradually stabilized after crossing the fault. The peak position of the event was about 40 m in front of the “square” or before the fault. When the mining speed of 1302 (top) working face is 50 m/month and the 1303 working face is 60 m/month, the frequency and energy are the largest. ②By analyzing the inducing factors and locations of large-energy events, large-energy events can be divided into three categories: “energy accumulation type” high-energy events, “fault activation type” high-energy events, and “island structure type” high-energy events, and put forward specific prevention and control measures for different types. The research in this article will provide reference for surrounding mines with similar geological factors and mining technical conditions.

[Objective] The spatiotemporal interactive coupling characteristics between mountainous urbanization and ecosystem health, and the complex relationship between ecosystem health and urbanization were studied to provide a scientific basis for the scientific management and sustainable development of urban areas in the region. [Methods] The spatial and temporal evolution characteristics of urbanization and ecosystem health subsystems were analyzed for Chongqing City (a mountainous city) from 2000 to 2020 using the entropy value method and the vigor-organizational-resilience-service (V-O-R-S) model to determine the mechanism of the interactive coupling relationship between urbanization and ecosystem health subsystems. [Results] ① The comprehensive urbanization level in Chongqing City from 2000 to 2020 increased year by year. However, there was still a problem of uneven spatial development, and both the core zone and the low-value area were significantly affected by topographic relief. ② The ecosystem health index from 2000 to 2020 was moderate. The ecosystem health of the regions with rapid urbanization deteriorated significantly, while the ecosystem health of Southeast Chongqing and Northeast Chongqing with higher vegetation cover was good. [Conclusion] The interactive coupling between urbanization and ecosystem health subsystems was on the rise, but has not yet reached a highly coordinated stage, and contradictions still exist. To achieve high-quality and sustainable development in Chongqing City, it will still be necessary to take the green development path and solve the problem of spatial and temporal inequality.

BackgroundIn the process of radiotherapy, when radiation kills tumor cells, it inevitably damages normal tissue cells. ObjectiveTo investigate the role of Toll-like receptor 4 (TLR4)/nuclear factor−kappa B (NF-κB) signaling pathway in the improvement of cognitive impairment induced by ionizing radiation by hydrogen-rich water before and after whole brain irradiation in rats. MethodsFifteen male SD rats were randomly divided into three groups: control group, irradiated group (IR group), and hydrogen-rich water intervention group (IR+HRW group), with 5 rats in each group. The control group was not irradiated, but was given purified water (20 mL·kg−1) by gavage every day, while the IR group and the IR+HRW group were irradiated with a single dose of 20 Gy. Three days before, 10 min before, and 30 days after irradiation, purified water/hydrogen-rich water (20 mL·kg−1) was given by continuous gavage every day. The general condition of the rats was observed every day, and the body weight were measured on the 7th, 14th, 21st, and 30th days after irradiation. On the 30th day after irradiation, the learning and memory ability of the rats was tested by Morris water maze; the pathological changes of hippocampus were detected by hematoxylin-eosin (HE) staining after sacrificing the rats; the contents of glutathione (GSH), malondialdehyde (MDA), interleukin-1β (IL-1β), and hydroxyl radicals in brain tissues were detected by enzyme linked immunosorbent assay (ELISA); the mRNA and protein expression levels of TLR4, NF-κB, NOD-like receptor pyrin domain 3 (NLRP3), and cysteinyl aspartate specific proteinase 1 (Caspase 1) were detected by quantitative real-time PCR (qRT-PCR) and Western blotting in the hippocampus of rats. ResultsAfter irradiation, the rats in the IR group showed symptoms such as head hair removal and salivation, while the symptoms of the rats in the IR+HRW group were milder. No animal died in the control and the IR+HRW groups, while one rat died in the IR group. From day 14 to day 30 after irradiation, the body weight of the rats in the IR+HRW group tended to be higher than that in the IR group, but the difference was not statistically significant (P>0.05). The Morris water maze results showed that the escape latency of the IR+HRW group was shortened compared with that of IR group from day 1 to day 5 except day 3, but the difference was not statistically significant (P>0.05). For the rats in the IR+HRW group, it took less time to reach the original location of the platform after removing the platform on day 6 and the number of crossing the platform and the residence time in the original platform quadrant increased (P0.05). The results of qRT-PCR showed that the mRNA expression levels of TLR4 and Caspase 1 in the hippocampus of the IR+HRW group were decreased compared with the IR group (P0.05). The results of Western blotting showed that the expression levels of TLR4 and Caspase 1 protein in the hippocampus of the IR+HRW group were decreased compared with the IR group (P0.05). ConclusionHydrogen-rich water can improve cognitive impairment induced by ionizing radiation in rats, and its mechanism may be related to regulating TLR4/NF-κB signaling pathway, inhibiting inflammatory factors, and attenuating oxidative stress.

BackgroundAt present, radiation therapy is widely used in clinical treatment of tumors. However, while radiation therapy damages tumor cells, it also injures surrounding normal tissues. Studies have shown that hydrogen is a potential radiation-protective agent. ObjectiveTo investigate the neuroprotective mechanisms of hydrogen-rich water activating phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/cysteinyl aspartate specificproteinase-9 (Caspase-9) signaling pathway in acute radiation-induced brain injury. MethodsForty male SD rats were randomly divided into four groups: control group, irradiation only group (IR), high-dose hydrogen-rich water intervention group (IR+HHRW), and low-dose hydrogen-rich water intervention group (IR+LHRW), 10 rats in each group. Except for the control group, animals in each group received a single 20 Gy whole brain irradiation. Animals in all groups were gavaged once a day from 3 d before irradiation to 7 d after irradiation, pure water (20 mL·kg−1) was given to the control and the IR groups, and hydrogen-rich water (20 mL·kg−1, 10 mL·kg−1) was given to the IR+HHRW and the IR+LHRW groups. After 7 d of intervention, 5 rats in each group were selected for the Morris water maze experiment for behavioral evaluation. Autopsies were conducted after anesthesia for the remaining animals and blood samples were collected for hematological analysis. Rat brains were harvested for TUNEL staining to observe neuronal apoptosis. HE staining was performed to observe histopathological changes, enzyme-linked immunosorbent assay was adopted to detect oxidative stress-related indicators, and real-time PCR and Western blotting were used to measure the expressions of PI3K/AKT/Caspase-9 pathway-related genes and proteins. ResultsThe body weight of rats receiving irradiation decreased after 7 d of irradiation compared with the control group (P

Anthocyanins are a water-soluble flavonoids widely distributed in dark grains, berries and vegetables. Anthocyanins have strong antioxidant and anti-inflammatory activities, and adequate intake of cereal-based anthocyanins can reduce the risk of chronic diseases including diabetes, cardiovascular disease, age-related macular degeneration and so on. This paper will review the health effects and mechanism of different cereal-based anthocyanins in chronic diseases, focuses on clarifying the distribution and content of anthocyanins in different grains, the effects of cereal anthocyanins regulating Nrf2, NF-κB, MAPK, and PI3K/AKT signaling pathways. The paper also points out the current utilization and development trend of cereal anthocyanins. This paper provides scientific evidence for fundamental research and product development of cereal-based anthocyanins in the fields of food and medicine.

According to the characteristics of cyanine tailings in Xiajiadian gold ore, hydrogen peroxide oxidation method and sodium percarbonate (solid hydrogen peroxide solution) oxidation method were carried out to test and study the effect of cyanogen-breaking tailings, aiming to make the cyanogen-breaking tailings meet the backfilling and utilization requirements of HJ 943-2018 《Technical Specification for The Control of Cyanide Residue pollution in the Gold Industry》. The results showed that the cyanide breaking effect of sodium percarbonate (solid hydrogen peroxide) oxidation method was not as good as that of hydrogen peroxide, but the pH value of cyanogen-containing tailings slurry was adjusted to 9, and 2 g/L hydrogen peroxide was used to break the cyanide for 1 h without adding the catalyst CuSO4. The total cyanide content of tailings could be reduced to less than 0.9 mg/kg, and the leaching toxicity index of tailings could meet the requirements of standard backfill utilization.

In order to screen L. plantarum with potential probiotic effect and safety, 114 strains of L. plantarum isolated from Sichuan Paocai were used as starting strains to conduct acid resistance, bile salt tolerance, resistance to simulated gastrointestinal fluid, auto-aggregation ability, pathogenic bacteria co-aggregation, antibiotic resistance and hemolytic research. After culturing in pH2.0 acidic conditions and 0.2% bile salt concentration, 13 strains with better tolerance were initially screened. The 13 strains were tested with simulated gastroenteric fluid, aggregation capacity, antibiotic resistance and hemolysis. The results showed that 13 strains simulated gastrointestinal fluid tolerance survival rate was higher than 75%, auto-aggregation ability 23%~52%, and the co-aggregation ability of pathogenic bacteria Listeria monocytogenes and Escherichia coli were 10%~29% and 16%~37%. The results of drug sensitivity and minimum inhibitory concentration (MIC) tests showed that the potential strains showed similar resistance to 10 common antibiotics in drug susceptibility and minimum inhibitory concentration (MIC) experiments. They were sensitive to β-lactam and amido alcohol antibiotics, and had strong resistance to aminoglycosides, quinolones, glycopeptides, macrolides and tetracycline antibiotics. There was no hemolysis phenomenon, indicating high safety. Therefore, the 13 strains of L. plantarum obtained from the primary screening had potential probiotics and high safety, and the research results would provide strain resources for the development of probiotics.

VEGF-VEGFR2 signaling pathway plays an important role in the course of psoriasis. Binding of VEGF to VEGFR2 induces receptor dimerization and autophosphorylation at multiple tyrosine sites, promoting the activation of the downstream ERK1/2 signaling pathway. Phosphorylated ERK1/2 is highly expressed in keratinocytes in psoriatic lesions, while VEGFR2 activation induces ERK1/2 phosphorylation and upregulates the expression of keratin K6, K16, and K17. At the same time, the activation of ERK1/2 can enhance inflammatory response and vascular proliferation. Therefore, blockade of VEGF-mediated vegF-VEGFR2 signaling pathway can regulate the expression of downstream genes in VEGF-VEGFR2 signaling pathway. VEGF and VEGFR2, the key molecules in VEGF-VEGFR2 signaling pathway, may serve as potential therapeutic targets for psoriasis. VEGF inhibitors can block vegF-VEGFR2 signaling pathway by inhibiting VEGF or VEGFR2, playing a therapeutic role in psoriasis. In this review, we review the recent advances in the involvement of VEGF-VEGFR2 pathway in psoriasis.

The arc stability and droplet transfer phenomenon in welding process were analyzed with the help of a high-speed camera system, and the correlation mechanism was explored of arc voltage-arc physical phenomenon-weld morphology and microstructure-mechanical properties of joints in MIG welding of 4 mm-thick 304 stainless steel. The results show that when the voltage is 20.6 V, the welding arc heat distribution is uniform, and the droplet transfer form is a stable and continuous short-circuit transfer. The macroscopic shape of weld is good, and the microstructure is vermicular ferrite. The welded joint has high strength and plasticity. When the voltage drops to 16.6 V, the arc length becomes shorter, and the droplet has been short-circuited before it grows up. Heat conduction is slow, and undercut defects and grooves appear on the upper surface of weld. Part of lathy ferrite appears in the microstructure of weld. When the voltage increases to 24.6 V, the arc energy diverges severely, and the stability and continuity of droplet transfer decrease. Irregular fish scales appear on the surface of weld. Insufficient penetration appears on the back of weld. More lathy ferrite is formed in the lower layer of weld. When the voltage is lower and higher, the strength and plasticity of welded joint are reduced.

Taking the addition amount of peony dew, the inoculation amount of starter and the addition amount of granulated sugar as single factor indexes, and the acidity, pH, water holding capacity, texture characteristics and sensory score of peony dew yogurt as evaluation indexes. The fermentation formula of peony dew yogurt was optimized by response surface analysis, and the microbial index, physical and chemical index and antioxidant activity of the product were analyzed. The results showed that the optimum fermentation formula of Peony flower yogurt was peony flower dew 4.0%, starter inoculum 0.2%, granulated sugar 7%. Under the optimized process conditions, the sensory score of peony yogurt was 96, which was close to the predicted value (96.242 points). The hardness, elasticity, viscosity, cohesion and viscosity of peony dew yoghurt were 3.892 N, 0.9985 mm, 3.275 N, 0.851 and 1.43 mJ, respectively, and the indexes were better than those of peony dew yoghurt. The water holding capacity of peony dew yoghurt was 81.5%, pH was 4.23, protein content was 3.01 g/100 g, fat content was 2.88 g/100 g, acidity was 78.85°T, and the number of lactic acid bacteria was 1.5×108 CFU/mL, Escherichia coli was not detected, and the test results met the national food safety standards. The scavenging rates of DPPH and hydroxyl radical of peony dew yoghurt (When the mass concentration was 25 mg/mL) were 63.2% and 59.5%, respectively. The antioxidant capacity was significantly better than that of original yoghurt. Peony juice yogurt has better quality and strong antioxidant activity.

The presence of iron and aluminum in the red mud affect the leaching and extraction of scandium and rare earths. Through the analysis and testing of the Bayer process red mud, a technical plan for the reduction and sintering to recover aluminum and iron was designed, and the process of the molten deep reduction and sintering to extract aluminum and iron from the red mud was systematically studied. Under the optimum conditions, the grade of iron concentrate is 73.97%, the recovery rate is 90.27%, and the dissolution rate of aluminum is 96.28%, the aluminosilicate mineral is converted into sodium aluminate, and the sodium aluminate solution is obtained by alkali leaching, which can be used to prepare polyaluminum chloride products in the subsequent. The iron-containing complex minerals in the red mud are transformed into magnetic magnetite and elemental iron, and the iron-containing minerals are recovered by magnetic separation to realize the coordinated recovery of iron and aluminum in the red mud. The process not only weakens the adverse effect of aluminum and iron ore on the subsequent extraction of scandium, titanium and rare earth by acid leaching, but also enriches titanium, scandium and rare earth in the tailings, which is conducive to the realization of multi-element comprehensive utilization of red mud.

In order to investigate the pathogenic microbial pollution of ready-to-eat fresh fruits and vegetables in Tianjin, 654 batches of samples of six kinds of ready-to-eat fruits and vegetables, such as lettuce, tomato, cucumber, chrysanthemum, peach and pear, were taken from the production and circulation links from 2015 to 2019. The total number of colonies, coliform, Salmonella, Staphylococcus aureus, Listeria monocytogenes, the pollution status of Bacillus cereus and Escherichia coli O157:H7 were analyzed. The results showed that 135 batches of foodborne pathogens were detected in 654 batches of samples, with a detection rate of 20.6%, including Salmonella 1, Staphylococcus aureus 6, Bacillus cereus 128, and no other pathogens were detected. The samples with high detection rate of foodborne pathogens mostly appeared in supermarkets and farmers’ markets, which indicated that the contamination of foodborne pathogens in fruits and vegetables was easy to occur in the post harveststage. Foodborne pathogen contamination in ready-to-eat fresh fruits and vegetables is a potential safety hazard to consumers' health. It is necessary to strengthen the prevention and control of postharvest circulation links, ensure the food safety of ready-to-eat fruits and vegetables and prevent the outbreak of foodborne diseases.

In recent years, edible and medicinal mushroom have been widely concerned by researchers at home and abroad for their unique biological activities. As one of the most potential mushrooms, Oudemansiella is high in protein, and low in fat and fiber, which has high value in food and medicine. Many studies have shown that the Oudemansiella polysaccharides have a wide range of biological activities, such as antioxidant, anti-inflammatory, immunomodulatory, antifungal, regulate intestinal flora and so on. This paper reviews the extraction method, chemical structure and biological activities of Oudemansiella polysaccharides in recent years to provide references for the further development and utilization of Oudemansiella edible mushroom.

This study explored the effect of six different cooking methods (steaming, roasting, microwave, combined mode, inductor cooker steaming and inductor cooker) on the retention and absorption of vitamin C and nitrate of broccoli during in-vitro simulated gastrointestinal digestion, in search of healthy cooking technology which was easy to digestion and absorption. The results showed that the cooking time of the induction cooker (1~3 min) was the shortest while the one for roasting (6~11 min) was the longest in achieving the same maturity of broccoli. In addition, the samples treated with microwave or steaming had the highest retention and digestion of vitamin C, and the samples of roasted, combined mode or induction cooker steaming displayed the highest retention and absorption rate of nitrate. Therefore, inductor cooker steaming mode (P5 and P9) was considered the most suitable method in cooking broccoli to obtain the most appropriate digestion and absorption of vitamin C and nitrate.

Oils and fats are an important source of energy for animals and a good carrier of fat-soluble nutrients, which can participate in various life activities of the body and are widely used in animal production. With the improvement of the scale of aquaculture, many kinds of oils and fats have been used in animal diets to improve production efficiency of aquaculture. The paper reviews the research progress on the application of dietary fat in the laying poultry industry, introduces the characteristics of digestion and absorption of oils and fats in laying poultry and the nutritional effect of oils and fats on laying poultry, discusses the effects of feeding with different kinds and levels of oils and fats on laying performance, egg quality, nutrients in eggs and health of laying poultry, in order to provide reference for the efficient application of oils and fats in laying poultry feed. [ABSTRACT FROM AUTHOR]

Background As a neurodegenerative disease, Alzheimer's disease (AD) has a high incidence rate and rapid development, which seriously affects the quality of life of patients. In recent years, research on music therapy intervention in AD has gradually increased, lacking effective systematic evaluation and analysis. Objective A meta-analysis was conducted on the intervention effects of music in the treatment of cognition, emotion, living ability and sleep disorders in AD patients. Methods Randomized controlled trials (RCT) on the intervention effect of music therapy methods on Alzheimer's patients were searched by computer in CNKI, Wanfang Data, VIP, Medline, Elsevier Science Direct, PubMed, and Embase from inception to February 2023, and the data was analyzed using RevMan 5.3 software. Results The study included 15 RCTs with a total of 1 077 patients. The results of Meta-analysis showed that the intervention effects of music therapy on cognitive function (MD=4.35, 95%CI=1.64 to 7.05, Z=3.15, P=0.002), negative emotion (SMD=-0.71, 95%CI=-1.26 to -0.15, Z=2.51, P=0.01), life ability (SMD=-0.91, 95%CI=-1.55 to -0.27, Z=2.77, P=0.006) in the music therapy group was better than that of control group. There was no significant difference in sleep disorder intervention between the two groups (MD=-1.04, 95%CI=-3.10 to 1.02, Z=0.99, P=0.32). Subgroup analysis showed that the music therapy groups with treatment period was

The natural environment spectrum and equivalent conversion relationship are important input parameters for the complication of aircraft acceleration test environment spectrum. Due to the large discrete nature of environmental data and the small number of sample data, traditional parameter estimation methods are no longer suitable for compilation of natural environment spectra. Based on the idea of small sample parameter estimation, this paper established a high confidence natural environment spectrum through Bootstrap data expansion and grey confidence interval estimation. Subsequently, electrochemical tests were carried out on 7050 aluminum alloy and TC18 titanium alloy, which were typical dissimilar metal connection materials for aircraft, and their equivalent conversion coefficients were calculated at the temperature of accelerated test environment based on the principle of isoelectric quantity. On this basis, the accelerated test environment spectrum of aluminum-titanium alloy joint structure was given, which could provide a reference for the engineering of calendar life assessment of aircraft dissimilar metal joint structure.

In order to effectively prevent and control the rock burst in the asymmetric pressure-relief working face under protective layer, taking the 0291 working face of Tangshan Coal Mine as the engineering background, the theoretical analysis and numerical simulation methods were adopted, and the potential influence factors of rock burst in the working face and the occurrence area were analyzed. The results show that the mining depth, bursting tendency of coal seam and its roof, residual pillars in upper protective layer and goaf of the coal seam and thick and hard roof are the potential influence factors of rock burst. Before mining, under the influence of the residual pillars in the protective layer and goaf, the stress of the two tunnels in the 0291 working face shows an asymmetrical distribution. The high stress area of the return airway is mainly located below the cutting line and stop line of the 0250 goaf, while the high stress area of the transportation roadway is mainly located below the cutting line of the 0251 goaf. The working face had obvious zonal characteristics. In the early stage of mining, the advanced stress in surrounding rock of transportation roadway is higher than that of return airway. It is necessary to strengthen the monitoring of transportation roadway and take pressure-relief measures in time. When the working face enters the lower part of 0251 goaf, the surrounding rock stress of the transport roadway decreases rapidly, and the prevention focus should be transferred from the transport roadway to the return air roadway. According to the results of numerical simulation, the impact zones can be divided and the prevention and control measures of impact zones in the mining were put forward. Field monitoring results show that the measures taken can effectively reduce the occurrence of rock burst.

Taking X100 and X80 pipeline steels as research objects，their stress-strain curves in air and under different applied potentials were obtained through the slow strain rate tensile test (SSRT).The stress corrosion sensitivity analysis showed that the applied potential had a significant effect on the SCC sensitivity and corrosion cracking mechanism of X100 and X80 pipeline steels in 3.5%NaCl neutral solution.Under the same stress corrosion conditions，the SCC sensitivity of X100 pipeline steel was lower than that of X80 pipeline steel.The characteristics and differences of the corrosion resistance of X100 and X80 pipeline steels were analyzed by combing the observation of fracture morphology and fast/slow scan tests of polarization curves，the stress corrosion mechanism type of X100 and X80 pipeline steel materials under different applied potential conditions could be obtained，when the applied potential was higher than -395 mV，the metal was in the state of activation dissolution；when the applied potential was -395～-462 mV(X80 steel) or -395～-504 mV(X100 steel)，the mechanisms were membrane crackinganodic dissolution(AD) and hydrogen induced crack.If the applied potential further decreased，the mechanism was hydrogen induced crack.

The resistivity of the anti-corrosion coating of buried steel pipeline is an important parameter.In recent years，the value of this parameter has been used to evaluate the overall quality of the anti-corrosion coating of in-service or directional drilling pipelines.All the domestic standards regarding the on-site measurement of this parameter and the evaluation of the overall quality of the anti-corrosion coating are established with reference to NACE TM 0102-2002.However，those domestic standards have not explained the concept of "anti-corrosion coating resistivity" clearly and there is confusion with terms related to "anti-corrosion coating resistivity".The reasons for selecting the general method and the attenuation method are not defined clearly for the measurement of the resistivity of anti-corrosion coating in various standards，and the test location of the soil resistance is not specified when the general method is used for the directional drilling crossing pipeline，resulting in differences in the field test results and evaluation conclusions of the resistivity of the anti-corrosion coating outside the same pipeline by various inspection units.In order to clarify the above problems，the concepts related to the resistivity of the anti-corrosion coating were explained firstly，and then the meaning of the resistivity of the anti-corrosion coating was clarified through theoretical analysis and formula derivation.Furthermore，the measurement results of the resistivity of the anti-corrosion coating of 100 directional drilling crossing pipelines were statistically analyzed.Finally，suggestions on the revision of relevant standards were given，with expect to revise the unclear problems in the new version of the standards.

To prepare excellent radiation protection material, bismuth tungstate nanocrystals were synthesized by hydrothermal method, and polyurethane based bismuth tungstate composites were prepared. The effects of crystal structure and morphology on the gamma ray shielding properties of bismuth tungstate were studied. The results indicated that the pH value of precursor solution had a large effect on the synthesis of bismuth tungstate, orthorhombic Bi2WO6 were obtained under acidic and neutral conditions, and tetragonal Bi0.875W0.125O1.6875 were obtained under strong alkali condition. With the increase of pH value, the morphology of bismuth tungstate changed from flower like microspheres to persimmon like microstructures, and then to randomly stacked nanosheets. It was found that orthorhombic persimmon-like Bi2WO6 showed higher shielding properties to 81 keV gamma rays, whereas tetragonal Bi0.875W0.125O1.6875 showed higher shielding properties to 59.5 and 121.8 keV gamma rays, obvious differences were observed between the mechanical properties of the composites prepared by different crystalline bismuth tungstate. The results of this study provide a reference for the development of new radiation shielding materials with non-toxic, light weight and high efficiency.

Background Arrhythmias are common complications in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) , however their occurrence and severity are not completely consistent with the severity of their disease per se. Our previous study found that pulse oxygen desaturation rate (ODR) was an independent predictor of the development of hypertension in OSAHS patients. We hypothesized that sleep apnea related ODR and heart rate fluctuation rate (HRFR) may predict the occurrence of arrhythmias in OSAHS patients. Objective To observe the correlation between ODR, HRFR and the occurrence of arrhythmias, and to explore the predictive value of ORD and HRFR on the occurrence of arrhythmias. Methods Polysomnography and Holter monitoring were performed on 36 patients who visited the sleep disordered breathing specialized outpatient clinic of the First Affiliated Hospital of Nanjing Medical University between January and June 2021, while basic clinical information of the patients was collected. Taking the median number of arrhythmic events as the cutoff value, the patients were divided into two groups: the patients with low incidence of arrhythmia group (

In order to study the effect of pre - oxidation treatment on the quality of the nitriding layer of stainless steel parts, quenched and tempered samples were treated with different pre - oxidation and sand blowing treatments before nitriding. The color of the preoxidized film was observed visually. The microstructure, depth, hardness, and brittleness of nitriding layer were measured by metallographic microscope and hardness tester. Results showed that the passivation film on the surface of 1Cr11Ni2W2MoV stainless steel could be destroyed if the steel was preoxidized at 550 ℃ for 5～20 min before nitriding. So the hardness, depth and structure of the nitriding layer could meet the technical requirements for nitriding if treated so. Furthermore, the uniformity and nitriding speed of the layer were better than that of the layer with only sand blowing treatment before nitriding.

Bag-of-Tasks (BoT) applications consisting of multiple tasks are widely used in various fields.Different from the traditional deadline constraint in scheduling problems,a due date constraint allows the BoT applications to finish more than a predetermined due date,but would result in the tardiness penalty.In this case,in order to reduce the total cost,the efficient harmony search (EHS) algorithm is proposed to optimize the scheduling tasks in hybrid clouds.The algorithm obtains the initial task sequence by random search and fine tuning.By improving the harmony search steps and the way of generating new harmony memory,a large number of high-quality harmony can be obtained in one search process,which greatly improves the efficiency of harmony search and speeds up the convergence speed of the algorithm.Through continuous iteration,the global optimal solution is obtained,that is to say,BoT application scheduling scheme has the lowest total cost.Experimental results show that compared with other algorithms,the proposed algorithm has significant improvement in performance,which can effectively reduce the total cost of scheduling BoT applications.

The failure of modular multilevel converter (MMC) submodules in the flexible direct current (DC) system affects the normal operation of the system, and the mutual restriction of reliability and economy is one of the key issues of MMC redundancy configuration optimization. A multi-objective optimization function of MMC reliability and economy mathematical model with redundant submodules was established. Based on the weight coefficient and NSGAII multi-objective optimization methods, a dual collaborative optimization for redundancy quantity of flexible controller was proposed. Combining the advantages of the two methods, the intersection of the two optimization results was calculated under the same redundancy quantity selection preference. A model based on a DC project in a flexible station area of Nanjing was built in MATLAB. The simulation results prove that the proposed method can not only meet the reliability of the flexible DC system, but also significantly improve the economy. It provides ideas for redundancy quantity of MMC submodules in the actual flexible DC project.

Both the new PWR steam generator and thermal hydraulic analysis software need to carry out experiment to verify the performance before engineering application. Onedimensional and threedimensional thermal hydraulic software of steam generator were used to obtain the distribution of key parameters, such as temperature, void fraction, pressure drop of support plate, etc., and optimize the design of the test simulator and the arrangement of measuring points. Following the simulation criterion of equal height, equal physical properties, and similar resistance, the steam generator simulator was designed, and the design of downcomer tube with full bore ball valve was used to realize the precise control and measurement of the circulating rate. The circulating rate was measured and calculated by the flow method and the thermodynamic method, and the relative deviation between the two methods is less than ±5%. The armored thermocouple sealing structure was designed to pass through the two layers of pressure boundaries to obtain the primary side temperature distribution along the heat transfer tube. The secondary side temperature distribution of steam generator and the height of the boiling start point were obtained. The guided wave radar liquid level gauge and the liquid level measurement by differential pressure were used to measure the water level of the steam generator with good followup, and the relative deviations of the two methods under steadystate and transient conditions do not exceed ±15%. The point, line and volume void fraction of the secondary side of steam generator were obtained by the optical fiber probe, gammaray method and differential pressure methods respectively. The relative deviation between the threedimensional calculation and test measurement results in the region of high void fraction does not exceed ±10%. For the central area of the tube bundle, the measurement value of the optical fiber probe is the highest. For the tube gallery area, the measurement values of the three methods are close, and reasons for the deviation of the measurement results among the three methods were analyzed. Considering that the pressure difference method needs to eliminate the error caused by frictional pressure drop, it is recommended to use the ray method to measure void fraction. The steam wetness (

Nicotinamide (NAM) is the amide form of niacin and one of the precursors of nicotinamide adenine dinucleotide (NAD + ). NAM can be used as a dietary supplement or clinical therapeutic drug to replenish NAD + levels in the human body and participate in key bodily functions such as cellular metabolism and DNA repair. NAM has the advantage of low cost, wide availability, and sound biosafety. It also has multiple biological functions, including antibacterial effect, anti-inflammatory effect, and modulation of cellular immunity, producing significant ameliorative effects on skin and neurodegenerative diseases. However, most studies on NAM are still at the laboratory stage. Herein we reviewed the role and mechanism of NAM in the prevention and treatment of oral and systemic diseases, explored its potential as clinical therapeutic medication, provided some basis and references for the clinical application of nicotinamide in the prevention and treatment of various diseases, and discussed its prospects for future research and application., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective: To explore the effects of nicotinamide (NAM) on the growth, biofilm formation and exopolysaccharides (EPS) production of Streptococcus mutans ., Methods: The minimum inhibitory concentration (MIC) of NAM on S. mutans was determined by the planktonic bacterial susceptibility assay. The NAM mass concentrations were set as 1/2 MIC, 1/4 MIC and 1/8 MIC for hree separate treatment groups. Culture medium without NAM was used in the negative control group and culture medium containing 0.1 mg/mL NaF was used for the positive control group (except for the scanning electron microscopy). The growth curves of S. mutans under different NAM concentrations were drawn. Crystal violet assay and anthrone-sulfuric acid method were used to explore the effects of NAM on S. mutans biofilm formation and water-insoluble EPS production, respectively. The morphology and structure of S. mutans planktons and biofilms after NAM treatment were observed by scanning electron microscopy., Results: The MIC of NAM on S. mutans was 32 μg/μL. After 16 μg/μL (1/2 MIC), 8 μg/μL (1/4 MIC) and 4 μg/μL (1/8 MIC) NAM treatments, S. mutans growth and biofilm formation were inhibited, with the 16 μg/μL NAM group displaying the most significant inhibitory effects. The synthesis of EPS decreased significantly in the 16 μg/μL and 8 μg/μL NAM groups in comparison with that of the negative control group ( P <0.05). Under scanning electron microscope, the cell length of S. mutans was shortened, the cell width was extended, and the length/width ratio was decreased, showing significant difference when comparing the 16 μg/μL and 8 μg/μL NAM groups with the negative control group ( P <0.05)., Conclusion: Under the influence of NAM at certain concenrations, the growth, biofilm formation, and EPS synthesis of S. mutans were inhibited., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)