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In order to improve the accuracy of gravity anomaly data processing, this study utilizes multi-scale surface fitting techniques (MSSF) to separate the Bouguer gravity field into residual gravity fields and regional gravity fields at different depths. By sequentially stripping away layers, the residual gravity anomalies of the target layer are obtained as the data basis for subsequent gravity interpretation. This study selects appropriate parameters and establishes different lithology forward modeling templates based on actual geological data in the study area. The method is verified to accurately separate gravity anomalies generated by different density bodies, with accurate anomaly locations, complete shapes, and clear boundaries. It can also serve as a quantitative template for rock properties and provide theoretical references for practical cases. Additionally, the method exhibits high noise resistance, resolution, and accuracy. The practical application of the method is validated through microgravity monitoring data in carbonate reservoirs in western China and time-shifted microgravity monitoring data in tight sandstone reservoirs. The results demonstrate that the obtained residual gravity anomaly data of the target layer can effectively reflect the distribution of reservoir fluids. [ABSTRACT FROM AUTHOR]

Trib. Lorantheae is one of the important medicinal plants in traditional medicine. There are 41 genera. 6 genera of which are produced in China, mainly distributed in Southwest China. South China and Central South China. There ar«-many kinds of plants in this family, and 22 species can be used as Chinese medicinal materials in China. The branches and leaves of Trib. Lorantheae are rich in flavonoids, alkaloids, terpenoids. polysaccharides. organic acids and other functional substances. among which flavonoids are one of the important chemical components to exert pharmacological activity. and play an important role in hypoglycemic. lipid-lowering, anti-inflammatory. anti-tumor, anti-oxidation, anti-osteoporosis and so on. In this paper, the chemical composition, extraction method, component analysis and pharmacological action of flavonoids in Trib. Lorantheae plants were reviewed. in order to provide scientific reference for further development and clinical application of flavonoids in Trib. Lorantheae plants. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first overview of co-authorship network of microplastics in landfill leachate. • Light color Polyethylene, Polypropylene, and Polystyrene are dominant in leachate. • Microplastics abundance is biased with different sampling and analysis techniques. • There are no global standards for microplastic management. Plastic wastes deposited in landfills eventually break down and degrade into microplastics by physical, chemical, and biological forces. Though microplastics in leachate pose significant threats to the environment, the leachate generated from landfills has not received much attention as a possible source of environmental microplastics. A descriptive and systematic investigation of the global distribution of microplastics in landfill leachate does not exist to date. Therefore, this attempt is to provide a concise scientometric review of the studies on the presence of microplastics in landfill leachate. The present review revealed that the global trend in research on microplastics in leachate has increased exponentially after 2018 and China is the leading country. Different geographical regions have reported different microplastic abundances with the highest of 291.0 ± 91.0 items/L from a landfill in Shanghai. The use of novel sampling techniques to detect small microplastics (20–100 µm) has led to the high abundance of microplastics in landfill leachate in Shanghai. Due to its widespread usage, polyethylene is the most typically encountered polymer type in landfill leachate around the world. However, it is quite challenging to compare the results among studies due to the use of different size categories and extraction techniques. The removal of microplastics by the current leachate treatment facilities is still mostly unexplored, thus it is crucial to develop novel technologies to treat the microplastics in landfill leachate. Further investigations on the transport of microplastics in landfill leachate are urgently required to have a better understanding of potential human exposure and health implications. [ABSTRACT FROM AUTHOR]

China's helium resource is highly dependent on overseas imports. Organic-rich and U/Th-rich shale reservoirs generally contain helium, and although the helium content is low, the total reserve is large. Therefore, the effective development and utilisation of shale-type helium resources is a realistic way to improve the security of helium resources in China. In this study, the generation mechanism, helium source and content, migration modes and pathways, controlling factors of enrichment, distribution pattern, and resource potential of the helium were analysed, using the Wufeng-Longmaxi shale in the Sichuan Basin and its periphery. Furthermore, countermeasures were proposed for shale-type helium exploration and development. The results show that the Wufeng-Longmaxi shale has a high content of U and Th and a good ability to generate helium. The helium is generated by a typical crustal source of helium and is characterised by self-generation, self-storage, and wide distribution. The helium resource potential is a product of its content and the resources of the associated natural gas. The continuous supply of helium and effective preservation are the main geological factors that control the enrichment of shale-type helium. The preliminary evaluation results show that the reserves of helium in proven shale gas reserves are 10.8×108 m3 in the Sichuan Basin and its periphery, where the extra-large helium fields are likely to be discovered. Additionally, 0.0912×108 m3 of helium was produced, along with the annual production of shale gas. To avoid the waste of helium and to improve the self-supply ability, it is suggested that research on the resource potential, enrichment mechanism, and distribution pattern of shale-type helium should be carried out as soon as possible, and helium extraction techniques for helium-bearing natural gas should be studied. [ABSTRACT FROM AUTHOR]

Bombax ceiba L. (Family: Malvaceae) was rightly called the "silent doctor" in the past as every part of it had medicinal value. For centuries, humans have used this plant according to the traditional medicinal systems of China, Ayurveda, and tribal communities. Recently, with an emerging interest in herbals, attention has been paid to scientifically validating medicinal claims for the treatment of diabetes using secondary metabolites of B. ceiba L. flowers. In the present study, specific secondary metabolites from the flowers of B. ceiba L. were isolated in good yield using the solvent extraction methodology, and their in vitro anti-diabetic efficacy was examined. Extraction efficiency of each solvent for secondary metabolites was found in following order: water > ethanol> methanol > chloroform > petroleum ether. Quantitative analysis of secondary metabolites showed 120.33 ± 2.33 mg/gm polyphenols, 60.77 ± 1.02 mg/g flavonoids, 60.26 ± 1.20 mg/g glycosaponins, 0.167 ± 0.02 mg/g polysaccharides for water extract; 91.00 ± 1.00 mg/g polyphenols, 9.22 ± 1.02 mg/g flavonoids, 43.90 ± 0.30 mg/g glycosaponins, 0.090 ± 0.03 mg/g poly saccharides for ethanol extract; 52.00 ± 2.64 mg/g polyphenols, 35.22 ± 0.38 mg/g flavonoids, 72.26 ± 1.05 mg/g glycosaponins, 0.147 ± 0.01 mg/g polysaccharides for methanol extract; 11.33 ± 0.58 mg/g polyphenols, 23.66 ± 1.76 mg/g flavonoids, 32.8 ± 0.75 mg/g glycosaponins, 0.013 ± 0.02 mg/g polysaccharides for chloroform extract; and 3.33 ± 1.53 mg/g polyphenols, 1.89 ± 1.39 mg/g flavonoids, 21.67 ± 1.24 mg/g glycosaponins, 0.005 ± 0.01 mg/g polysaccharides for petroleum ether extract. Glucose uptake by yeast cells increased 70.38 ± 2.17% by water extract. [ABSTRACT FROM AUTHOR]

Cotton is one of the Uyghur medical materials in China and is rich in flavonoids. Flavonoids have important pharmacological effects. The yield of flavonoids in traditional extraction methods is low, which affects the development of flavonoids. Therefore, it is urgent to optimize the extraction techniques. The yield of flavonoids in cotton flowers was effectively improved by response surface methodology, and the highest yield of flavonoids reached 5.66%, and the optimal extraction process conditions were obtained. The DPPH free radical scavenging rate, hydroxyl free radical scavenging rate, superoxide anion free radical scavenging rate, and reducing ability were tested to reflect the antioxidant capacity of flavonoids. The flavonoids had an excellent antioxidant effect. Cell experiments suggested that the flavonoids had the effect of protecting glutamate-induced damage to HT-22 cells. The results of this study provide a theoretical basis for the extraction of cotton flowers flavonoids and the comprehensive evaluation of antioxidant products, as well as the extraction of other plant flavonoids. [ABSTRACT FROM AUTHOR]

Helium, a rare gas widely applied in high-tech fields, is a significant strategic resource in China. The foreign-trade dependence ratio of helium in China is 95%. The work reviewed the applications and market analysis of helium and reservoir modeling and distribution of helium in Changqing Gas Field as well as the helium extraction techniques from natural gases. According to the analysis of the component test and the dynamic monitoring of exploited gas wells and gas-gathering stations, the average helium content in Changqing Gas Field was 0.028%. Helium was rich in the northwest of Changqing Gas Field, but poor in the central and eastern regions. The helium volume contents in Qingyang Gas Field, Huanglong Gas Field, and the central, western, and southern regions of Sulige Gas Field have reached the industrial development standard. PetroChina performed the economic-feasibility evaluation and production-factor matching research on helium development and selected Changqing Gas Field as the demonstration for development. A large helium plant was established in Changqing Gas Field using the cryogenic method with/without membrane separation for helium extraction. Then, a helium development scheme was formulated and implemented to build the industry chain of helium in China. Changqing Gas Field is rich in helium resources. Developing helium has entered a strategic period with the technological advancement in extracting helium from natural gases and the increased prosperity of the international helium market. There are broad prospects and great benefits to exploiting helium resources in Changqing. [ABSTRACT FROM AUTHOR]

With the growing global energy demand and limited production of conventional crude oil, the extraction of unconventional heavy and extra-heavy oil is receiving unprecedented attention. China is the fourth largest producer of heavy oil. High viscosity and complex formation environments increase the difficulty of exploiting heavy oil. To alleviate the economic cost and environmental pollution pressure brought by heavy oil production, China has achieved significant advancement in the innovation of heavy oil recovery, including accelerating the transformation of thermal technology to non-thermal technology and the use of new energy technology to achieve the goal of low-carbon economy and green environmental protection. Based on the background of heavy oil in China, this paper recharacterizes the high-viscosity mechanism of heavy oil. From different aspects, including basic principles, main characteristics, applicability, limitations, and challenges, this paper comprehensively reviews existing heavy oil recovery technologies, including thermal recovery, in-situ upgrading, cold recovery, and new energy technologies. Currently, in China, the main target of heavy oil recovery is achieving the "carbon peaking and carbon neutrality" goals, which can be described as low energy consumption, low emission, and low pollution. To facilitate the low-carbon transition in the extraction of heavy/extra-heavy oil and attain environmental sustainability goals, it is essential to increase the proportion of non-thermal factors in thermal recovery technologies, develop efficient in-situ catalysts, adopt clean cold extraction techniques, and advance the development of new energy technologies. [ABSTRACT FROM AUTHOR]

Citrus seed waste material provides a new solution for addressing the shortage of edible oils in China. supercritical CO 2 fluid extraction (SFE), sub-critical butane fluid extraction (SCE), cold press (CP), soxhlet extraction (SXE), and ultrasonic-assisted extraction (UAE) were preformed to obtain Ougan (Citrus reticulata cv. Suavissima) seed oil. Ougan seed oils were tested for physicochemical properties, fatty acid composition, limonoids, polyphenols, total carotenoids, tocopherols, and in vitro antioxidant activities. The results indicated that SCE Ougan seed oil has the most abundant fatty acid composition, and higher in vitro antioxidant capacity, which is mainly positively related to the polyphenol, carotenoid and tocopherol contents. Therefore, SCE may be the optimum procedure for extracting a high content of bioactive substances from Ougan seed oils, providing a theoretical foundation for developing high-quality and nutritional value Ougan seed oils. [Display omitted] • Different extraction processes have significant effects on the quality of Ougan seed oils. • The composition of fatty acids in SCE Ougan seed oil is more abundant. • SCE Ougan seed oil contains higher content of bioactive substances. • SCE Ougan seed oil shows stronger antioxidant capacity. • There is a positive correlation between polyphenols, tocopherols, carotenoids and antioxidation in Ougan seed oils. [ABSTRACT FROM AUTHOR]

The brain seems to be the most complex organ in the human body and operates as the central part of the nervous system. The classification of brain tumors is the most complicated problem which medical experts face. In our proposed work, the novelty is that we have adopted the hybridization of feature exaction techniques and a conglomerate of classification methods. The hybrid features are extracted from the tumor region using the Gray Level Co-occurrence Matrix technique and shape-based features. There are three different types of brain magnetic resonance imaging datasets used in work. For the segmentation, the Marker-controlled watershed segmentation strategy is implemented in this work. In this work, the hybrid classifier, which includes the Random Forest (RF) classifier, K-Nearest Neighbour classifier, and Decision Tree classifier, is implemented. Dataset 1 (China Hospital data) shows a better overall accuracy of 98.75%; for dataset 2, accuracy is 98.99%; and for dataset 3, the achieved accuracy is 98.92%. The other parameters that prove the overall work's efficacy include sensitivity, precision, specificity, F1-score, Cohen's kappa value, Dice coefficient, Jaccard Index, and area under the curve (AUC). The proposed work is also compared with the state-of-the-art methods and observed better one. [ABSTRACT FROM AUTHOR]

Organic components in atmospheric fine particulate matter have attracted much attention and several scientific studies have been performed, although most of the sample extraction methods are time consuming and laborious. Accelerated solvent extraction (ASE) is a new sample extraction method offering number of advantages, such as low extraction cost, reduced solvent and time consumption, and simplified extraction protocols. In order to optimize ASE methods to determine the concentrations of organic compounds in atmospheric fine particulate matter, different parameters were set out for the experiment, and the optimal method was selected according to the recoveries of the standard (i.e., n−alkanes and polycyclic aromatic hydrocarbons (PAHs)). This study also involves a comparison of the optimal method with the traditional method of ultrasonic extraction (USE). In addition, the optimized method was applied to measure the mass concentrations of organic compounds (n−alkanes and PAHs) in fine particulate matter samples collected in Beijing. The findings showed that the average recovery of target compounds using ASE was 96%, with the majority of compounds falling within the confidence levels, and the ASE recoveries and precision were consistent with the USE method tested. Furthermore, ASE combines the advantages of high extraction efficiency, automation, and reduced solvent use. In conclusion, the optimal ASE methods can be used to extract organic components in atmospheric particulate matter and serve as a point of reference for the development of analytical methodologies for assessing organic compounds in atmospheric particulate matter in China. [ABSTRACT FROM AUTHOR]

It is well established that arsenic (As) has many toxic compounds, and in particular, inorganic As (iAs) has been classified as a type-1 carcinogen. The measuring of As species in rice flour is of great importance since rice is a staple of the diet in many countries and a major contributor to As intake in the Asian diet. In this study, several solvents and techniques for the extraction of As species from rice flour samples prior to their analysis by HPLC-ICP-MS were investigated. The extraction methods were examined for their efficiency in extracting various arsenicals from a rice flour certified reference material, NMIJ-7532a, produced by the National Metrology Institute of Japan. Results show that ultrasound-assisted extraction at 60 °C for 1 h and then heating at 100 °C for 2.5 h in the oven using a thermostable α-amylase aqueous solution was highly effective in liberating the arsenic species. The recoveries of iAs and dimethylarsinic acid (DMA) in NMIJ-7532a were 99.7% ± 1.6% (n = 3) and 98.1% ± 2.3% (n = 3), respectively, in comparison with the certificated values. Thus, the proposed extraction method is a green procedure that does not use any acidic, basic, or organic solvents. Moreover, this extraction method could effectively maintain the integrity of the native arsenic species of As(III), As(V), monomethylarsonate (MMA), DMA, arsenobetaine (AsB) and arsenocholine (AsC). Under the optimum extraction, chromatography and ICP-MS conditions, the limits of detection (LOD) obtained were 0.47 ng g−1, 1.67 ng g−1 and 0.80 ng g−1 for As(III), As(V) and DMA, respectively, while the limits of quantification (LOQ) achieved were 1.51 ng g−1, 5.34 ng g−1 and 2.57 ng g−1 for As(III), As(V) and DMA, respectively. Subsequently, the proposed method was successfully applied to As speciation analysis for several rice flour samples collected from contaminated areas in China. [ABSTRACT FROM AUTHOR]

Goji (Lycium barbarum L.) also known as wolfberry, is one of important medicinal plants in China that has been in use for its medicinal properties and as food supplement for centuries. The abundant bioactive compounds in its fruit, leaves, and root bark are considered beneficial to human health. Phenolic compounds were extracted from different locations of Goji leaves, including tip bud leaves (GBL), young leaves in the middle (GYL), and old leaves at the base (GOL). The phenolics from Goji leaves using ethanolic condensation backflow extraction (EE), ultrasonic extraction (UE), and enzymatic extraction (ME) were prepared, and their polyphenol concentration and antioxidant ability were analyzed. Polyphenol in Goji leaf varied with different positions and extraction techniques. Total 47 phenolic compounds were identified by HPLC-MS, including 43 in GBL, 38 in GYL, and 26 in GOL. Chlorogenic acid, hyperoside, and rutin were the main phenols in Goji leaves, and the highest content of chlorogenic acid in GBL-UE was 2105.05 ± 77.25 µg /g. All Goji leaves showed significant antioxidant effect and polyphenol content, especially GBL that having the highest phenolic level and the stronger antioxidant capacity. Different extraction methods for different leaf positions could improve the extraction efficiency, UE and ME were found suitable for extracting GBL and GOL samples; EE and UE were suitable for extracting GBL samples. GBL exhibited better phenolics and better antioxidant attributes, which are suitable for the development of nutraceuticals and skincare products. [Display omitted] • 47 phenolic compounds were identified from Goji, including 43 in GBL, 38 in GYL, and 26 in GOL. • Chlorogenic acid and rutin were the main phenolic substances in Goji leaves. • The highest phenolic content was found in GBL, followed by GYL and the least in GOL. • For polyphenol extraction, UE and ME were suitable for GBL and GOL; EE and UE were suitable for GBL. • Our study provides a theoretical basis for the industrial utilization of Goji leaves. [ABSTRACT FROM AUTHOR]

[Display omitted] • DESs-UAE protocol was first developed to extraction of the bioactive flavonoids from Jiang Fructus aurantii. • DESs-UAE protocol was optimized by using RSM. • Extractability of DESs were better than that of the conventional solvents. • The extraction efficiency of the UAE was significantly higher than that of the traditional methods. • DESs-UAE protocol has the potentiality in the efficient extraction of bioactive ingredients from TCM. In China, Jiang Fructus aurantii (JFA) has attracted increasing interest as a famous traditional herbal medicine and valuable economic food for its valuable medicinal and industrial properties. In the current work, contrasted with conventional extraction techniques, natural flavonoids from JFA (naringin and neohesperidin) were extracted with remarkable effectiveness utilizing a sustainable deep eutectic solvents combined ultrasonic-assisted extraction (DESs-UAE) protocol. The optimal extraction capacity can be achieved by mixing 30 % water with a molar ratio of 1:3 for choline chloride and ethylene glycol, as opposed to the classical extraction solvents of 95 % ethanol, methanol, and water. Moreover, the DESs-UAE extraction programs were also systematically optimized employing Box-Behnken design (BBD) trials, and the eventual findings suggested that the best parameters were a 27 % water content in DES, a 16 mL/g liquid–solid ratio, a 72 min extraction time, and a 62 °C extraction temperature, along with the corresponding greatest contents of NAR (48.18 mg/g) and NEO (34.50 mg/g), respectively. Notably, by comparison with the pre-optimization data, the optimized DES extraction efficiency of flavonoids is markedly higher. Thereafter, the characterization of the solvents before and after extraction, as well as the differences between the four extraction solvent extracts, were compared using the FT-IR analyses. Furthermore, SEM results suggested that the penetration and erosion abilities of the plant cell wall of DES-1 were stronger than those of the other three traditional solvents, thus allowing more release of flavonoid compounds. In conclusion, the present research develops a straightforward, sustainable, and exceedingly efficient approach for the extraction of bioactive flavonoids from JFA, which has the potential to facilitate the efficient acquisition of active ingredients from TCM. [ABSTRACT FROM AUTHOR]

Deep learning-based semantic segmentation methods, such as fully convolutional networks (FCNs), are state-of-the-art techniques for object extraction from high spatial resolution images. However, collecting massive scene-formed training samples typically required in FCNs is time-consuming and labour-intensive. A suit of automatic sample augmentation schemes based on simulated scene generation is proposed in this study to reduce the manual workload. Proposed schemes include style transfer, target embedding, and mixed modes by utilizing techniques, such as texture transfer, image inpainting, and region-line primitive association framework, which automatically expand the sample set on the basis of a small number of real samples. Dock extraction experiments using UNet are conducted on China's GaoFen-2 imagery with expanded sample sets. Results showed that the proposed schemes can successfully generate sufficient simulation samples, increase sample diversity, and subsequently improve semantic segmentation accuracy. Compared with the results that use the original real sample set, measures of F1-score (F1) and intersection over union (IoU) of dock extraction accuracy demonstrate a maximum improvement of 20.53% and 23.01%, respectively, after sample augmentation. [ABSTRACT FROM AUTHOR]

• Chemical compounds were extracted simultaneity by ultrasonic assisted method. • Flowers of Citrus maxima (FCM) have obvious free radical scavenging capacity. • Hot water and ethanol are used as solvents to extract the same raw material. • The proposed production improved the value of Citrus maxima resources. Ultrasonic assisted extraction is frequently referred to as a green environmental protection method. The flower of Citrus maxima (FCM) has been used as a health tea drink in China, although the tea drink lacks clear compound composition identification and functional research. In order to fully use Citrus fruit by-products and further explore the functional features of FCM, this paper isolated, identified, and assessed the chemical compounds in the petals, stems, styles, receptacles, stamens, and buds of FCM extract. There are 88 compounds were recovered, including 23 compounds in the bud, 21 compounds in the petal, 19 compounds in the stem, 11 compounds in the receptacle, 20 compounds in the stamen, and 13 compounds in the style. Antioxidant experiments revealed that the FCM's various compounds had observable impacts in scavenging free radicals (38.44%–58.35%). The aforementioned study demonstrates that the pomelo by-products were developed into useful components using ultrasonic aided extraction technique. FCM has flavor-rich compounds that make it suited for use as an antioxidant tea beverage and offers practical suggestions for preparing healthy products. [ABSTRACT FROM AUTHOR]

• Amino-containing MOFs MIL-125-NH 2 was designed as a new sorbent in d-SPE. • MIL-125-NH 2 enrich the target analytes directly to improve sensitivity. • Amino-containing MIL-125-NH 2 has good adsorption capacity. • The detection limits were lower than most of traditional methods. • MIL-125-NH 2 is recovered easily and reused at least 8 times. A simple, environmentally-friendly and reliable method was developed to simultaneously monitor the residue of methyl 1-naphthalene acetate, parathion-methyl, fenitrothion, bromophos and phenthoate in pomelo by using dispersive solid-phase extraction technique (d-SPE). In this method, these target analytes were captured by MIL-125-NH 2 and detected by GC–MS/MS. The key parameters of d-SPE were optimized by the single factor experiment. Under the optimized conditions, a good determination coefficient (R2 > 0.9922) and extraction recoveries (64.7–116.8%) are obtained. The limit of detections (0.03–1.07 ng/g) is lower than the MRLs in citrus fruits established by EU (10–15000 ng/g) and China (10–10000 ng/g). The precisions of intra-day and inter-day are 1.3–8.9% and 3.8–14.9%, respectively. In addition, the sorbent MIL-125-NH 2 is stable and can be reused at least eight times. These results prove the established method is efficient and reliable to detect the pesticide residues in pomelo. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPPs) are among the most commonly used pesticides worldwide. However, these compounds pose a serious threat to aquatic environments. Here, thirty-seven pesticides and eight degradation products were determined in surface water samples from Tai Lake, East China, using a high-volume solid phase extraction technique (Hi-throat/Hi-volume SPE). Surface water was pumped in-situ through a portable sampler, and OPPs in the water retained on the Hi-volume SPE adsorption column, finally extracted for analysis. This technique efficiently reduced the detection limits to below 0.3 ng/L. In total, 40 out of 45 OPP congeners were detected, which far exceeded the amount of OPPs in previous studies. The total concentration of OPPs ranged between 101.4 and 1530 ng/L (median: 378.9 ng/L). Parathion exhibited the highest concentration (median: 112.0 ng/L), followed by paraoxon-methyl (median: 90.3 ng/L), as well as carbophenothion, fenthion, and mevinphos. Agricultural areas were more polluted than residential and industrial regions. However, degradation products persisted in residential and industrial waters. The ecological risks of OPPs in these areas were estimated based on the risk quotient index (RQ). Parathion, fenthion, carbophenothion, and tolclofos-methyl occurred at high-risk levels, and the levels of degradation products were also non-trivial. Our findings thus indicated that OPP degradation products pose a potential threat to natural environments and should therefore be closely monitored. [Display omitted] • Hi-throat/Hi-volume SPE technique was efficiently applied in assessing OPPs. • OPPs and degradation products detected in surface water of East China. • Degradation products persist in industrial and residential waters. • Parathion, fenthion, carbophenothion, and tolclofos methyl exhibited high risk. • Threating degradation products of OPPs needed further management. [ABSTRACT FROM AUTHOR]

• Proposed composite drought index is simple and easy to calculate. • Proposed index is reliable to detect soil moisture. • Index performs well in monitoring drought conditions. Numerous studies have projected that drought will become more severe under changing climatic conditions which will have a profound impact on terrestrial ecosystems around the world. While a wide range of drought indices has been extensively applied to assess droughts, various issues have been raised, such as over- or underestimation of drought conditions, feature extraction techniques, or transformations used to develop the indices. In this study, a new composite drought index (CDI) was developed using the integration of potential and actual evapotranspiration, climatic water balance, and precipitation. The proposed CDI was evaluated by comparing it with soil moisture, Palmer Drought Severity Index (PDSI), scaled crop yield index (sCYI), evaluation integrated drought index (EIDI), and standardized runoff index (SRI) in China. Our results demonstrate that together with PDSI, CDI performs well in monitoring drought over 2417 grid cells obtained from in-situ latitude and longitude. It was found that CDI performs better than the PDSI and EIDI for reliable soil moisture detection and stable drought monitoring in the study area. Compared to PDSI, CDI shows a more positive correlation with sCYI for seasonal maize and wheat. CDI has less false alarm ratio in the detection of mild to extreme drought events compared to PDSI. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of lactic acid on didymium and Lanthanum separation by SX process was studied. • The continuous SX process comprising three steps: extraction, scrubbing and stripping. • Didymium and lanthanum were obtained with high recovery and high degree of purity. • Conditioning the feed liquor with lactic acid increased the selectivity of the separation. • The addition of lactic acid is more sustainable than the practice of saponification of extractants. Rare earth elements (REE) have increased in importance in the world due to the diverse applications in high-tech industries. The fact that Brazil has the world's second largest REE reserves makes it a potential producer of these elements. However, for that to occur, it is necessary to have knowledge about the production technologies of rare earths, mainly the technologies used in the refining stages, in which China predominates. Generally, the leached solution contains a mixture of REE and the main challenge is to improve selectivity during their separation and purification. For this reason, techniques to improve the efficiency of the separation of these elements have been widely studied in recent years. In the present study, we seek to define efficient routes for the separation of lanthanum (La) from didymium (Pr and Nd) by the solvent extraction technique (SX), using the organophosphorus extractant 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) from a liquor conditioned with lactic acid. Isotherms were constructed using the McCabe-Thiele method to estimate the number of theoretical stages and the aqueous/organic ratio (A/O) necessary to achieve efficient separation during the process. In continuous solvent extraction experiments, REE recovery percentages and purity of didymium and lanthanum above 90% were obtained. Didymium with 99.9% purity was obtained in a circuit with nine extraction stages (extraction A/O ratio of 4:1) and seven scrubbing stages (scrubbing A/O ratio of 2:1). The results presented here show that the use of lactic acid can be a promising alternative to boost the efficiency of the solvent extraction process for the separation of these light rare earth elements. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) are typical industrial additives widely applied in various industrial and household products, but they may pollute drinking water. In the present study, the occurrence of OPEs in drinking water was analyzed. For this purpose, 25 drinking water samples were collected from households in 25 cities in China. The concentrations of OPEs were accurately determined according to a high-throughput organic analysis testing combined with high-volume solid phase extraction (Hi-throat/Hi-volume SPE) technique. Through this technique, nine OPEs were detected, with spiked recoveries from 77% to 101%, and their total concentrations (ΣOPEs) ranging from 46.8 to 251 (average 126) ng L−1. The detection frequencies of the selected OPEs determined via Hi-throat/Hi-volume SPE were 88.0%–100%, which are much higher than those previously reported. The limit of detections of the OPEs was low at < 0.01 ng L−1, which could be mainly attributed to the high volume of accumulated drinking water (>20 L). OPEs in drinking water presented a decreasing trend from cities in coastal provinces to inland cities of China. Redundancy analysis showed that the concentrations of OPEs in drinking water were significantly influenced by economic–demographic influencing factors. The non-carcinogenic and lifetime carcinogenic risks (non-CR and CR) of the analyzed OPEs in drinking water were negligible for urban residents in China. [Display omitted] • Ten organophosphate esters in drinking water of China were analyzed. • Tris(1-chloro-2-propyl)phosphate was the predominant OPE in drinking water. • Organophosphate esters in drinking water were related to anthropocentric activities. • Health risks of organophosphate esters in drinking water of China were negligible. [ABSTRACT FROM AUTHOR]

Methane safety extraction is an effective method for reducing methane concentration in the gob and enhanced coal-bed methane recovery that is widely used in China. Although there is already extensive research on this technique, dip angle coal of seams has unpredictable effects on methane extraction locations, which is an influential factor that has rarely been studied, especially where the seam dip angles are larger. The benefits of this paper include improving methane extraction techniques, exploring the fractal characteristic of channel, and developing the laws governing how channels emerge, especially where coal seam dip angles vary. The results show that with increased coal seam dip angle, the height and width of channels show an increasing trend, along with crack angle. Key parameters of the methane migration channel boundaries in mutant regions of the bed separated under inclined coal mines were also defined. In the laboratory, an effective model was put forward to calculate the evolution characteristics of channels under inclined coal mining using fractal and elliptic paraboloid zone theory (EPZ); the finding was that the height of the A region at 30° was 1.34 and 2.00 times that of 15°, 0°, respectively. Moreover, borehole methane extraction concentration in area B increased to 6.04% in field application. The research results are expected to benefit industry and mine safety staff when arranging the position of high-level boreholes. The findings can enhance safety levels and improve efficiency in inclined coal mining. • A model for fractal dimension under inclined coal mine prediction proposed. • The main controlling factors for the methane migration channel was identified. • It was divided into three areas by fractal dimension in vertical gradient. • The model can estimate high-level borehole position under inclined coal mine. [ABSTRACT FROM AUTHOR]