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To improve transmission line load capacity and prevent power grid accidents, an online sag monitoring system for overhead transmission lines based on spontaneous Brillouin scattering is designed using the principles of Brillouin scattering and coherent detection. Brillouin Optical Time Domain Reflection (BOTDR) technology is used to collect the strain signal distributed along the optical fiber in real time, extract the key features of strain sensing, and realize the accurate positioning and early warning of sag anomaly points. Laboratory data and substation test results show that the system can detect and accurately locate strain change information in real time. The strain monitoring system is simple in single-end measurement and can accurately locate the strain mutation point. It can realize the early warning of cable sag abnormalities, and can timely detect and deal with potential faults to ensure the safe and stable operation of the transmission line.

BACKGROUND The Jiulong area in western Sichuan is an important rare metal production area in China, which has a large resource potential. As an ecological protection barrier on the upper reaches of the Yangtze River, the ecological environment of this area is fragile. Facing the huge opportunities of mining development and under the current situation of 'environmental protection first', it is urgent to investigate the environmental background of this area to support the development of national energy strategy. OBJECTIVES To evaluate the ecological risk of heavy metals in soils from the Jiulong Li-Be mining area. METHODS A total of 352 soil samples were collected. The concentration of 7 heavy metals (Cd, As, Pb, Cr, Cu, Ni, Zn) in soil was analyzed by NexION 300x inductively coupled plasma-mass spectrometer (ICP-MS). The comprehensive assessment methods including geoaccumulation index, pollution load index, potential ecological risk index, and health risk model, combined with GIS spatial analysis were used to study the spatial distribution characteristics and ecological risk of heavy metals in the soil. RESULTS The average concentration of all 7 heavy metals in the soil in Jiulong did not exceed the Chinese national standard. There was no soil heavy metals pollution in the studied area. Compared with the soil background value of Sichuan Province, the average concentrations of As and Pb were lower than the background; the concentrations of Cd, Cr, Cu, Ni, and Zn were higher than the background, which were 2.44, 1.04, 1.15, 1.28, and 1.17 times the background values, respectively. The spatial distribution characteristics of these elements except As were affected by biotite granite in the study area. The high concentration center of Pb and the low concentration center of Cr, Cu, Ni and Zn had an obvious correspondence with the spatial position of the rock mass. Except for the weak accumulation indicated by Cd Igeo, there was no accumulation of other heavy metals. Similarly, there was no potential ecological risk in the study area, except for the slight potential ecological risk of Cd. Spatially, the distribution of Cd single element potential ecological risk index was related to the rock mass, and the area without potential ecological risk corresponded to the location of the biotite granite rock mass. Heavy metals in the soil can enter the human body through direct contact with hands, mouth, and skin, and through inhalation. The hand-to-mouth approach is the most important way to generate health risks among all 3 approaches. Except hand-to-mouth approach of Cr, which has an acceptable and normal natural carcinogenic risk, there is no carcinogenic risk for other metals. CONCLUSIONS At present, there is no pollution of heavy metals in the soil in the studied area. The potential risk of heavy metals is low, and there are no non-carcinogenic and carcinogenic risks. However, due to the cumulative effect of heavy metals in the soil, close attention must be paid to changes in the concentration of heavy metals in the soil in the future mining development process, to prevent the risk caused by heavy metals pollution.

BACKGROUND When inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine the rare earth elements (REE) in the barite-associated light rare earth ores, Ba and light rare earth elements La, Ce, Pr, Nd, Sm, cause severe mass spectral overlap interference to the medium and heavy rare earths. Therefore, under the condition that complete digestion of oress, if the appropriate pretreatment method can be selected to achieve effective separation of the target elements from the matrix, it will be beneficial to reduce mass spectrum interferences. OBJECTIVES To reduce the mass spectrum interferences by establishing a simple and effective pretreatment method for separation of rare earth elements from barium and other coexisting elements in barite-associated rare earth ores. METHODS The barite-associated rare earth ores samples were fused with sodium peroxide and sodium carbonate. After dissolution of the fusion cake, the target REE and the undesired barium were precipitated in triethanolamine solution, but some matrix elements like Si, Fe, Mg, and Al in samples, and most fusion agents, were separated by filtration. The target REE were secondly precipitated in ammonium hydroxide after dissolution of the precipitates by acid, so that Ba, Sr and Ca could be separated from REE. The separation exceeds 96%, so the mass spectrum interferences caused by barium polyatomic ions were effectively reduced. In addition, the interference correction coefficients by measuring the interference concentration at m/z 138-175 of the high concentration lighter rare earths standard single element solution were adopted to account for the oxide and hydroxide overlap problem for the determination of middle and heavier rare earth elements. RESULTS The validity of the method was evaluated by analyses of rare earth ores certified reference materials and the results were in good agreement with certified values (|RE| < 10%). For the actual sample analysis of the barite-associated rare earth ores, the relative standard deviations (n=12) were from 0.5% to 4.6%, which proved that the method can be used to analyze rare earth elements in high-Ba ores. CONCLUSIONS The results demonstrate that this method is both practical and effective for rare earth elements analysis in barite-associated rare earth ores.

BACKGROUND Under the background of coordinated development of resources, environment and economy, the development of green mining has become a national strategic focus and has been widely recognized. Environmental investigation and evaluation is one of the main content in investigation and assessment of large lithium metallic mineral bases in Sichuan Province, which will play an important role in solving the bottleneck problems, such as prospecting deployment and environmental protection in the ecologically fragile district of the Western Sichuan Plateau. OBJECTIVES To put forward the green investigation method and to establish an index system of environmental evaluation and demonstration of typical mining areas. METHODS Green investigation and environmental assessment were combined, an indicator framework in four levels was constructed, and the status quo and change information of the ecological environment through 3S technology were extracted. Based on three years of surface water, soil and other multi-environmental media field survey and analysis data, a mature evaluation method has been optimized, and a large-scale lithium resource base environment evaluation model based on support vector machine was established by using a more compatible and scalable Python language programming. RESULTS Using this model, the current status of large-scale bases was divided into four categories:environmentally poor areas, general environmental areas, better environmental areas, and good environmental areas. The overall accuracy rate was 97.77%. CONCLUSIONS The set of a targeted evaluation index system established and reported on in this paper effectively evaluates the environmental status of large-scale lithium resource bases in Western Sichuan, and realizes the visual level of 'pixel-level' environmental status of large-scale lithium resource bases through technological innovation. The method objectively reflects the development and environmental impacts of the Jiajika mining area and surrounding resources, and to a certain extent, can assist in regulating the management and decision-making of the development and utilization of large-scale mineral resources.

In recent years, low-salinity waterflooding has become the focus of research in the petroleum industry owing to its enormous advantages, including high efficiency in displacing oils, ease of injection into oil-bearing formations, easy access and operation of water, and low investment and pollution, all of which are more cost-effective compared to other enhanced oil recovery methods. Numerous experimental studies and field trials of sandstone and carbonate rocks have proven that low-salinity waterflooding can enhance oil recovery effectively due to various mechanisms, including fines migration and mineral dissolution, increased pH effect and reduced interfacial tension, multicomponent ion exchange, and double-layer expansion. As an important mechanism of low-salinity waterflooding, fines migration induced by lowering injected water salinity can effectively change reservoir quality and injection profile, thereby achieving equilibrium displacement and enhance oil recovery. Several models and mathematical equations that describe particle release and capture have been proposed by many scholars in previous studies, and the maximum retention concentration function of fine particles is considered to be the most effective method for describing fines migration. Based on the Derjaguin-Landau-Verwey-Overbeek theory and electric double-layer theory of colloid stability, the effect of injected water salinity and ion valence on the clay particle force and particle migration concentration were analyzed from the microcosmic view in this paper, and the relationship between the particle migration concentration and the permeability impairment was established through maximum concentration of attached fine particles. Aiming at the problem of interlayer interference in vertically heterogeneous reservoir, the numerical simulation of low-salinity waterflooding was carried out in high water-cut stage. Force analysis and numerical simulation results show that the high-permeability layer with high injected water flow rate will cause the hydration, expansion, migration, and clogging of a large amount of clay particles, leading to a marked permeability decline in the high-permeability layer. More injected water is diverted into low-permeability and middle-permeability layer with low sweep efficiency. The injection profile and interlayer interference is relieved. Therefore, the production degree of reservoirs and cumulative oil recovery improve by approximately 3% beyond conventional seawater flooding.

BACKGROUND The Sichuan Jiajika ore field is one of the most concentrated areas of lithium resources in China and even in the world. At present, the understanding of the spectroscopy of the Jiajika lithium deposit is still very poor. OBJECTIVES To better understand the spectra of lithium ore deposits and provide the basis for hyperspectral study of lithium ore deposits by spectrum measurement of typical rocks. METHODS Spectra of typical rocks and minerals collected in Jiajika area were measured by Analytical Spectral Devices (ASD) FieldSpec-4 Spectroradiometer and a spectral library of this area was built. The spectral characteristics of rocks and minerals including biotite schist, grenatiteschist, grenatite cordieriteschist, hornstone, granite, pegmatite containing spodumene, pegmatite without spodumene, quartz vein, feldspar, spodumenemono, biotite, aquamarine were analyzed. RESULTS The results indicate that there are differences in spectral characteristics between rock masses and surrounding rocks. The reflectance of surrounding rocks is less than 0.2, and absorption characteristics are not obvious, whereas the reflectance of rock masses is less than 0.5, and there are three absorption features at 1413 nm, 1911 nm, 2197 nm. In addition, granite, pegmatite containing spodumene, and pegmatite without spodumene can be discriminated by their unique spectra on 1413 nm and 2197 nm. The unique spectral characteristics of spodumene and aquamarine can be applied for ore exploration. CONCLUSIONS The research on the surface spectroscopy of the Jiajika type lithium ore deposit carried out in this paper has important guiding significance for hyperspectral remote sensing mapping and geological prospecting.

BACKGROUND A new deposit type with a scheelite-beryl-molybdenite assemblage was first discovered in the Zhen'an area of Shaanxi Province. BAOBJECTIVES The research on chromatic mechanism and genetic mechanism of emerald was carried out. METHODS Combined with the geological survey, Electron Microprobe and in-situ Micro X-ray Diffractomer were used to conduct mineral research. RESULTS The emerald mainly occurs in the quartz (calcite) veins as euhedral crystal and is associated with scheelite. Both the core and rim of the emerald with high V2O3 contents of 0.64%-0.98% and 1.04%-1.42%, respectively, show an increased V2O3 trend from core to rim. Diffraction data show that the emerald is normal beryl and has two kinds of isomorphous substitution mechanism, Al↔Me2+ and Be↔Li. Vanadium is the main coloring element of emerald and was mainly derived from carbonaceous slate, mica schist, and dolomitic marble, whereas Be, Si and Al were derived from deep acidic igneous rocks. CONCLUSIONS The discovery provides basic geological data for the comprehensive development and utilization of tungsten and antimony mineral resources in the deposit, and indicates new prospecting directions for continued searching for rare metal deposits in the region and deep areas of the South Qinling.

Aim at highly nonlinear mapping relationship between the laser processing parameters and the melting cell body’s transverse size，a method of reverse engineering laser melting parameters by back － propagation ( BP) neural network was put forward． The model was constructed by BP neural network，and the prediction error was reduced to less than 3% after training for many times． The DIEVAＲ die steel was melted by reverse engineering laser parameters，and the results show that the error was 1． 33% between the transverse dimensions of the melting cell body and the expected，the expected precision can be met well． Thermal fatigue property of the melted and non － melted DIEVAＲ die steel has been studied． The analysis about cracks growth presents that thermal fatigue property of DIEVAＲ die steel melted by the reverse engineering parameters has been greatly improved． The melting cell body could block crack effectively．

For high density polyethylene pipe connection，welding technology is the key of the high density engineering plastic pressure pipe safety. And the temperature distribution in the welding process has a very important influence on the welding quality. Polyethylene pipe weld joints of one dimensional unsteady overall heat transfer model is established by MARC software and simulates temperature field and stress field distribution of the welding process，and the thermocouple temperature automatic acquisition system of welding temperature field changes were detected，and compared by simulation and experiment .The results show that，at the end of the heating，the temperature of the pipe does not reach the maximum，but reached the maximum at 300 s，which indicates that the latent heat of phase change in the process of pressure welding. In the process of pressure welding， the axial stress of the pipe is gradually changed from tensile stress to compressive stress.

Sichuan Province is one of the most important provinces in China for light rare earth element (LREE) resources, where has been produced a large amount of rare earth concentrate in the past 20 years. Rare earth elements ΣREEs) and other useful elements in rare earth concentrates are very important for resource evaluation and enterprise survival. In this paper, geochemistry of rare earth elements (REEs) and trace elements in samples from the A, B and C REE deposits has been studied. The results show that the content of REEs and trace elements in rare earth concentrate samples are changed in different deposit, enterprise and different mineral dressing process. The lowest level of ΣREEs is from A (ΣREEs=41.96%), the highest level is from C (ΣREEs=55.83%). ΣREEs of magnetic concentrate (ΣREEs=49.96%) is higher than flotation concentrate (ΣREEs=41.57%), and ΣREEs from Jia Company (ΣREEs=48.35%) is higher than from Yi Company (ΣREEs=42.92%). The REE distribution patterns of concentrate sample are inherited from rare earth ores while Tb and Yb are depleted, indicating that the mineral dressing process may lead to loss of these elements. REEs are enriched in concentrate sample, and Mo, Bi, Pb, Ga, Th, U, W are also enriched. Especially, Mo and Ga are in cut-off grade. These results indicate that it is necessary to increase REE grade of rare earth concentrate, and to take appropriate measures to reclaim higher concentration elements.

Sichuan Province is one of the most important provinces in China for light rare earth element (LREE) resources, where they have been mined for more than 20 years. There is now a large volume of tailings present in the mines still containing an abundance of rare earth resources. It would be beneficial to the mine owners to recover the REEs in the tailings so an estimate of the amount would be extremely beneficial. Preliminary research has already been undertaken on the geochemistry of trace and rare earth elements in tailing samples from the A, B, C and D REE deposits. The results show that the REE distribution patterns of tailing samples are inherited from rare earth ores in REE deposits. The contents of rare earth oxides (REO) in samples are higher than the current cut-off grade (0.5%-1.0%), and the old tailings are higher than the new. In addition to the enrichment of REEs, samples of B (Sr 10%) and C (Sr 2.7%) are also rich in Sr while A samples are rich in Ba (1.8%). Mo, Bi, Pb and Ag are enriched in different degrees in all samples and in particular, the Mo content reached its cut-off grade, at 2.275% in the tailings of magnetic separation. It is evident from these results that it is necessary to protect tailings in rare earth mines in Sichuan Province, and to take appropriate measures to reclaim higher concentration elements.

The paper analyzed development requirements of communication system of coal mine in China and existed problems of main communication technologies of coal mine at present, and proposed a scheme of wireless communication system of integration of underground and surface based on TD-SCDMA. It introduced networking structure and functions of the system. The test result showed that the system can seamlessly cover underground operation area, surface dispatching control area and living area, which not only can meet with communication requirements of safety production but also realize command and dispatching under special situation.

Abstract Background The generic and oral health-related quality of life (QoL) has provided opportunity for investigation of the interrelations among generic health, oral health, and related outcomes. The purpose of this study was to identify the generic and oral QoL in the patients with oral mucosal disease (OMD). Methods Five hundred and thirty-eight OMDs were recruited in this study. The instruments applied were Chinese version of the 36-item short form health survey (SF-36) and the short-form of Oral Health Impact Profile (OHIP-14). Results The mean score of sum OHIP-14 was significantly higher in the patients with OMD (10.81 ± 9.01) compared with those in the healthy subjects (HS) (6.55 ± 6.73) (p < 0.001, Mann-Whitney U test). 56.51% of the OMD patients and 12.94% of the HS reported at least one oral negative impact (p < 0.001, Chi-square test). The overall mean score of SF-36 was significantly lower in the patients with OMD (74.54 ± 12.77) compared with those in the HS (77.97 ± 12.39) (p = 0.021, t-test). Conclusions Administration of specific and generic questionnaires of QoL can provide us a detailed picture of the impact of OMDs on patients, and both generic and oral QoL were impaired in the patients with OMD.

Background: Winter rapeseed, the sole overwintering oilseed crop in northern China, emphasizes winter resilience, yet epigenetic regulatory mechanisms governing overwintering memory remain poorly understood. Results: In this study, the root collar tissues from the robust cold-resistant variety Longyou-7 were sampled during the pre-winter period (S1), overwintering periods (S2–S5), and re-greening period (S6), to analyze overall genomic DNA methylation levels using high-performance liquid chromatography (HPLC). The result showed that DNA methylation level exceeded 80% in the S1 stage. Throughout the overwintering periods, methylation levels displayed a decreasing trend in S3, followed by an increase in S5, and a pronounced decrease in S6. Consequently, S1, S3, S5, and S6 periods were chosen for whole-genome bisulfite sequencing analyses to elucidate the overwintering memory mechanisms of Longyou-7. The result revealed that DNA methylation primarily occurs in the CG context in Longyou-7. However, methylation of mC sites is most prevalent in the CHH type, gradually decreasing during overwintering periods. Analysis of methylation patterns in specific genomic regions of Longyou-7 showed that the highest methylation levels in the intergenic region. Moreover, mC sites in repeats and transposon elements are distributed differently across the three contexts. Subsequently, differentially methylated regions and promoters of Longyou-7 were identified during various periods compared to the S1 stage, followed by joint analysis with transcriptome sequencing. Functional enrichment analysis highlighted the involvement of most overlapping genes in the MAPK signaling pathway, plant hormone signal transduction, and starch and sucrose metabolism pathways. Changes in candidate gene expression within these three pathways correlated closely with DNA methylation levels. Conclusions: Our findings underscored the critical role of DNA methylation in regulating the expression of overwintering memory genes in winter rapeseed. These results offer a comprehensive insights into the epigenetic regulatory mechanisms governing winter rapeseed's overwintering memory, while identified overwintering memory genes served as crucial genetic resources for multifaceted breeding of winter-resistant varieties. [ABSTRACT FROM AUTHOR]

Summary: Rare variants contribute significantly to the 'missing heritability' of quantitative traits. The genome‐wide characteristics of rare variants and their roles in environmental adaptation of woody plants remain unexplored.Utilizing genome‐wide rare variant association study (RVAS), expression quantitative trait loci (eQTL) mapping, genetic transformation, and molecular experiments, we explored the impact of rare variants on stomatal morphology and drought adaptation in Populus.Through comparative analysis of five world‐wide Populus species, we observed the influence of mutational bias and adaptive selection on the distribution of rare variants. RVAS identified 75 candidate genes correlated with stomatal size (SS)/stomatal density (SD), and a rare haplotype in the promoter of serine/arginine‐rich splicing factor PtoRSZ21 emerged as the foremost association signal governing SS. As a positive regulator of drought tolerance, PtoRSZ21 can recruit the core splicing factor PtoU1‐70K to regulate alternative splicing (AS) of PtoATG2b (autophagy‐related 2). The rare haplotype PtoRSZ21hap2 weakens binding affinity to PtoMYB61, consequently affecting PtoRSZ21 expression and SS, ultimately resulting in differential distribution of Populus accessions in arid and humid climates.This study enhances the understanding of regulatory mechanisms that underlie AS induced by rare variants and might provide targets for drought‐tolerant varieties breeding in Populus. [ABSTRACT FROM AUTHOR]

Blue light photoreceptor cryptochrome 1 (CRY1) in herbaceous plants plays crucial roles in various developmental processes, including cotyledon expansion, hypocotyl elongation and anthocyanin biosynthesis. However, the function of CRY1 in perennial trees is unclear. In this study, we identified two ortholog genes of CRY1 (PagCRY1a and PagCRY1b) from Populus, which displayed high sequence similarity to Arabidopsis CRY1. Overexpression of PagCRY1 substantially inhibited plant growth and promoted secondary xylem development in Populus, while CRISPR/Cas9‐mediated knockout of PagCRY1 enhanced plant growth and delayed secondary xylem development. Moreover, overexpression of PagCRY1 dramatically increased anthocyanin accumulation. The further analysis supported that PagCRY1 functions specifically in response to blue light. Taken together, our results demonstrated that modulating the expression of blue light photoreceptor CRY1 ortholog gene in Populus could significantly influence plant biomass production and the process of wood formation, laying a foundation for further investigating the light‐regulated tree growth. Summary statement: Light is one of the most important environmental signals that govern plant growth and development. This study demonstrated that the blue light photoreceptor PagCRY1 substantially promotes wood formation and anthocyanin biosynthesis in Populus, and provides evidence showing that HY5 and BBX6 may act downstream of PagCRY1 to activate lignin and anthocyanin biosynthesis. [ABSTRACT FROM AUTHOR]