In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, whi...In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.展开更多
A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differ...A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.展开更多
Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-infl...Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.展开更多
Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests ...Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests of northeastern China.Its seeds exhibit primary morphophysiological dormancy following dispersal in autumn,limiting natural or artificial regeneration:direct seeding and planting seedlings in spring.The aim of this study was to determine the optimum cold stratification temperature that induces germination to increase towards lower temperatures.Seeds from two populations(Changbaishan and Liangshui)were cold stratified at 0,5 and 10℃.Germination to incubation temperatures(10/5,20/10,25/15 and 30/20℃;14/10 h day/night)were determined after 2 and 4 weeks,and 5.5 and6.5 months of cold stratification.After 5.5 months,approximately 68-91%of seeds from both populations germinated at incubation temperatures of 25/15℃and 30/20℃,regardless of cold stratification temperatures.When the cold stratification temperature was reduced to 0℃and the period increased to 6.5 months,germination at 10/5℃significantly improved,reaching 37%and 64%for the Changbaishan and Liangshui populations,respectively.After 6.5 months of cold stratification,there was a significant linear regression between cold stratification temperatures and germination at10/5℃.The range in temperatures allowing for germination gradually expanded to include lower temperatures with decreasing cold stratification temperatures from 10 to 5℃and further to 0℃.展开更多
As significant evidence of permafrost degradation,thermokarst lakes play an important role in the permafrost regions by regulating hydrology,ecology,and biogeochemistry.In the Sources Area of the Yellow River(SAYR),pe...As significant evidence of permafrost degradation,thermokarst lakes play an important role in the permafrost regions by regulating hydrology,ecology,and biogeochemistry.In the Sources Area of the Yellow River(SAYR),permafrost degradation has accelerated since the 1980s,and numerous thermokarst lakes have been discovered.In this paper,we use Sentinel-2 images to extract thermokarst lake boundaries and perform a regional-scale study on their geometry across the permafrost region in the SAYR.We also explored the spatiotemporal variations and potential drivers from the perspectives of the permafrost,climate,terrain and vegetation conditions.The results showed that there were 47,518 thermokarst lakes in 2021 with a total area of 190.22×106 m^(2),with an average size of 4,003.3 m^(2).The 44,928 ponds(≤10,000 m^(2))predominated the whole lake number(94.1%)but contributed to a small portion of the total lake area(28.8%).With 2,590 features(5.9%),small-sized(10,000 to 100,000 m^(2))and large-sized lakes(>100,000 m^(2))constituted up to 71.2%of the total lake area.Thermokarst lakes developed more significantly in warm permafrost regions than in cold permafrost areas;74.1%of lakes with a total area of 119.6×106 m^(2)(62.9%),were distributed in warm permafrost regions.Most thermokarst lakes were likely to develop within the elevation range of 4,500~4,800 m,on flat terrain(slope<10°),on SE and S aspects and in alpine meadow areas.The thermokarst lakes in the study region experienced significant shrinkage between 1990 and 2021,characterized by obvious lake drainage;the lake numbers decreased by 5418(56.1%),with a decreasing area of 58.63×106 m^(2)(49.0%).This shrinkage of the thermokarst lake area was attributable mainly to the intensified degradation of rich-ice permafrost thawing arising from continued climate warming,despite the wetting climatic trend.展开更多
Background:Himalayan Griffons(Gyps himalayensis),large scavenging raptors widely distributed in Qinghai-Tibetan Plateau,have evolved a remarkable ability to feed on carcasses without suffering any adverse effects.The ...Background:Himalayan Griffons(Gyps himalayensis),large scavenging raptors widely distributed in Qinghai-Tibetan Plateau,have evolved a remarkable ability to feed on carcasses without suffering any adverse effects.The gut microbiome plays an important role in animal physiological and pathological processes,and has also been found to play a health protective role in the vulture adaptation to scavenging.However,the microbial taxonomic diversity(including nonculturable and culturable microbes),functions,and metabolites related to Himalayan Griffons have not been fully explored.Methods:In the present study,the 28 fecal samples of the Himalayan Griffons and 8 carrion samples were collected and sequenced using high-throughput 16 S rRNA gene sequencing methods to analyze the composition and functional structures of the microbiomes.Twelve fecal samples of the Himalayan Griffons were analyzed using untargeted Liquid Chromatography Mass Spectroscopy(LC-MS)to identify metabolites.We used different culture conditions to grow Himalayan Griffons gut microbes.Inhibitory effects of gut beneficial bacteria on 5 common pathogenic bacteria were also tested using the Oxford cup method.Results:According to the results of the culture-independent method,a high abundance of four major phyla in Himalayan Griffons were identified,including Fusobacteria,Firmicutes,Bacteroidetes,and Proteobacteria.The most abundant genera were Fusobacterium,followed by Clostridium_sensu_stricto_1,Cetobacterium,Epulopiscium,and Bacteroides.The predicted primary functional categories of the Himalayan Griffons'gut microbiome were associated with carbohydrate and amino acid metabolism,replication and repair,and membrane transport.LC-MS metabolomic analysis showed a total of 154 metabolites in all the fecal samples.Cultivation yielded 184 bacterial isolates with Escherichia coli,Enterococcus faecium,Enterococcus hirae,and Paeniclostridium sordellii as most common isolates.Moreover,7 potential beneficial gut bacteria isolated showed certain inhibition to 5 common pathogenic bacteria.Conclusions:Our findings broaden and deepen the understanding of Himalayan Griffons'gut microbiome,and highlighted the importance of gut microbiome-mediated adaptation to scavenging habits.In particular,our results highlighted the protective role of gut beneficial bacteria in the Himalayan Griffons against pathogenic bacteria that appear in rotten food resources.展开更多
With the aid of geophysical measurements,including seventeen two-dimensional(2 D)seismic lines and the well logging curves of well FGY1,the structure and reservoir characteristics of the Upper Ordovician–Lower Siluri...With the aid of geophysical measurements,including seventeen two-dimensional(2 D)seismic lines and the well logging curves of well FGY1,the structure and reservoir characteristics of the Upper Ordovician–Lower Silurian strata in the Fenggang block,northern Guizhou Province,were analyzed thoroughly to identify desert areas and favorable intervals.The results show that Longmaxi-Wufeng is the most prospect-rich formation,consisting of a thick succession of overmature black shale,this formation remaining partially in the Suiyang,Fenggang and Jianchaxi synclines.The Longmaxi-Wufeng shale,especially the lower member,was deposited in a reducing low-energy environment with relatively high U content and a low Th/U value.In this shale,the organic matter type(sapropelic and humic-sapropelic),total organic carbon(TOC)content,gas content,gas adsorption capacity,vitrinite reflectance and brittle mineral content are profitable for shale gas preservation and development.The fractures of this shale were closed because of its high overburden pressure.The gas adsorption capacity of this shale increases with increasing TOC content and Ro.In the Longmaxi-Wufeng Formation at well FGY1,the most favorable intervals are in the depth ranges of 2312.4–2325.1 m and 2325.8–2331.1 m.展开更多
The Qulong porphyry Cu-Mo deposit,generated in the Miocene post-collisional extension environment of the Gangdese Copper(Molybdenum)Metallogenic Belt,is one of the largest porphyry Cu deposits in China.This study repo...The Qulong porphyry Cu-Mo deposit,generated in the Miocene post-collisional extension environment of the Gangdese Copper(Molybdenum)Metallogenic Belt,is one of the largest porphyry Cu deposits in China.This study reports the noble gas isotopic compositions of volatiles released from fluid inclusion reserved in pyrite from the Qulong deposit.3He/4 He and 40Ar/36Ar ratios range from 0.54 to 1.015 Ra and 300-359,respectively.Concentrations of 4 He and 40Ar range from 1.77 to 2.62×10^(-8)cm^(3)STP and 1.7-34×10^(-8)cm^(3)STP,respectively.The isotopic composition of noble gases indicates that the ore-forming fluids of the Qulong Cu-Mo deposit were a mixture of fluid containing mantle component,which is exsolved from the porphyry magma,and crustal fluid characterized by atmospheric Ar and crustal radiogenic He.Theδ34S values of pyrite and molybdenite range from-0.52‰to 0.31‰,with an average of-0.12‰,indicating a magmatic origin.More mantle components were involved in the Cu-Mo deposit than in the Mo-Cu deposit in the Qulong-Jiama ore-district.展开更多
Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing...Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing on seed dispersal and germination of B.hancei,we measured the dispersal distance at varying wind speeds and release heights,falling duration from different release heights,floating duration on still water,rates of imbibition of water,and drying and soil adherence to seeds.Germination experiments were conducted on intact and de-winged seeds immediately after harvest.The wing increased the falling duration in still air and the floating ability on water.Dispersal distance of winged and de-winged seeds did not differ at a wind speed of 2.8 m s1,but at 3.6 and 4.0 m s1 dispersal distances were greater for de-winged than for winged seeds.Seed wing had little effect of absorption and retention of water,but significantly increased soil adherence to the seeds.Mature seeds were non-dormant and germinated to over 90%with a mean germination time of about 10 days.By combining the environmental conditions in karst habitat with the seed traits of B.hancei,we conclude that dispersal and germination of winged seeds are adapted to the precipitation seasonality in heterogeneous habitats absence of soil.展开更多
Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesti...Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.展开更多
In order to explore the influence of wet nitrogen(N)deposition on N output in watersheds,this study selected a typical small watershed(Chenjiagou,CJG)in the Three Gorges Reservoir(TGR)area based on one-year observatio...In order to explore the influence of wet nitrogen(N)deposition on N output in watersheds,this study selected a typical small watershed(Chenjiagou,CJG)in the Three Gorges Reservoir(TGR)area based on one-year observation of rainfallrunoff N forms.Characteristics and sources of N output were clarified by chemical statistics and isotopic abundance,and the contribution of N deposition to the N output was quantified by the output coefficient method.The N flux of wet deposition was estimated at 18.53 kg N ha^(-1) yr^(-1),and originated mostly from agricultural activities.Watershed N was significantly accumulated from upper to lower reaches due to frequent human activities.Seasonal changes of riverine N were strongly affected by chemical fertilizer,with the highest concentration in spring and the lowest in winter.Nitrate was mainly derived from chemical fertilizer,accounting for 38.83% of all sources.N concentration in processes of different rainfall events had a hysteresis effect corresponding to the flow rate.Three rainfall events greatly changed DTN(Dissolved total N)outputs:rainstorm caused 91.26 kg DTN output,which was 11 times that of moderate rain(8.46 kg)and 4 times that of heavy rain(20.80 kg).N deposition contributed 19.89% of riverine N output in the watershed.The results can provide theoretical support for the control of N pollution in the TGR area.展开更多
Firstly,the advantages and disadvantages of constructed wetlands for treating rural domestic sewage are introduced.Secondly,the types of constructed wetland plants are introduced.Thirdly,the suitability of using medic...Firstly,the advantages and disadvantages of constructed wetlands for treating rural domestic sewage are introduced.Secondly,the types of constructed wetland plants are introduced.Thirdly,the suitability of using medicinal wetland plants to treat rural domestic sewage is analyzed.Fourthly,the principles of selecting wetland plants with medicinal value are studied.Finally,commonly used constructed wetland plants and their medicinal value are introduced.展开更多
[Objectives] The research aimed to study the effect of sludge extract on the growth of Zinnia elegans, and evaluate its possibility of application. [Methods] Z. elegans was taken as research object, and the effect of ...[Objectives] The research aimed to study the effect of sludge extract on the growth of Zinnia elegans, and evaluate its possibility of application. [Methods] Z. elegans was taken as research object, and the effect of sludge extract on the growth indicators of Z. elegans was studied. [Results] The sludge extract can obviously promote the growth of Z. elegans, and the growth indicators were significantly improved when compared with the control group. The application effect was close to that of foliar fertilizer purchased in the market. In each treatment group, the low concentration of sludge extract did not significantly promote the growth of Z. elegans, while too high concentration could inhibit its growth, and the optimal dilution ratio was 600 times. [Conclusions] Further preparation of amino acid foliar fertilizer from sludge extract and its application in planting garden plants can realize the resource utilization of sludge and has a good development and application prospect.展开更多
Triclosan(TCS)has been manufactured as an antibacterial compound for half a century.Currently,it is widely used in various personal care products;however,its potential adverse effects raise a lot of attention.Here,we ...Triclosan(TCS)has been manufactured as an antibacterial compound for half a century.Currently,it is widely used in various personal care products;however,its potential adverse effects raise a lot of attention.Here,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of TCS.We discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic fibrosis.Further study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,respectively.Accompanied by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron disorder.Not only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to ferroptosis.Additional study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,individually.Taken together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin axis.Meanwhile,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver fibrosis.Ferriprox■,an iron scavenger,significantly ameliorates TCS-induced liver fibrosis.In summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also displayed.The significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.展开更多
Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river ecosystems.Previous views suggested that labile components were dominantly consumed by microbial metabolism.Here we prov...Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river ecosystems.Previous views suggested that labile components were dominantly consumed by microbial metabolism.Here we provide new observations that a part of recalcitrant compounds largely contribute to riverine DOM biodegradation.The excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component variability during DOM incubation.Humic-like and tryptophan-like DOM are the primary components of riverine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,respectively.After 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are observed.Elevated temperature enhances the decomposition of ultraviolet humiclike substance and further stimulates labile DOM bio-mineralization into carbon dioxide.Meanwhile,averaged proportions of amino acid compositions(peak B and T)markedly increase(p<0.05)as the humic-like compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight compounds.The findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps”,contributing to a new understanding of carbon cycling for the UN Sustainable Development Goal.展开更多
Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited condi-tions.Preparation methods contribute to biochar properties,which are widely concerned in the agronom...Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited condi-tions.Preparation methods contribute to biochar properties,which are widely concerned in the agronomic and environmental benefits of agro-ecosystems.This research aims to use bibliometrics methods to comprehensively and objectively analyze the research trends in the global biochar production field from 2006 to 2019 based on the Web of Science Core Collection database.The results showed that 1434 papers related to biochar preparation were published,which gradually increased each year.The research topics were diversified,which were mainly divided into“Environmental Sciences and Ecology,”“Engineering”and“Agriculture”.Moreover,Bioresource Technology was the most published journal contained biochar preparation.Authors from China had the most publications,followed by the US,Australia and the UK.Meanwhile,Yong Sik Ok from Korea University contributed most of the publications and had the highest H-index.Keywords analysis indicated that biochar preparation by pyrolysis was a current hotspot,of which microwave and hydrothermal were a future research trend.Besides,gasification would be used to develop new biomass energy.Biochar has the characteristics of high pH,high specific surface area,high carbon content,and rich functional groups.It is mainly used in soil improvement,water pollutant adsorption,carbon sequestration and emission reduction,and energy storage materials,etc.Furthermore,raw materials,pyrolysis temperature and pyrolysis time will also affect its characteristics and applications.It is expected that this study may provide insight into the future research interests regarding biochar preparation.展开更多
Mercury(Hg) in rice is drawing mounting concern since methylmercury(MeHg) was found capable of accumulating in rice. In-vitro bioaccessibility is a feasible and reliable method to assess the health effects of Hg in ri...Mercury(Hg) in rice is drawing mounting concern since methylmercury(MeHg) was found capable of accumulating in rice. In-vitro bioaccessibility is a feasible and reliable method to assess the health effects of Hg in rice and has been utilized in a number of studies. This study was done to investigate the impact of cultivar, planting location, and cooking on the total mercury(THg) and MeHg bioaccessibility of rice, for which multiple statistical analysis methods were used to analyze the significance of their effects. The THg concentrations of rice samples taken from non-Hg contaminated areas of China were all below 15 ng/g and their MeHg concentrations were below 2 ng/g. Cooking could significantly reduce the MeHg bioaccessibility of rice because the MeHg was mainly combined with protein and the protein will be denatured during the cooking process, and then the denatured MeHg is difficult to be dissolved into the liquid phase. Indica-and japonica-type rice cultivars did not show significant differentiation in either the concentration of Hg or its bioaccessibility. However, the glutinous rice type differed significantly from the above rice types, and it showed greater bioaccessibility of THg and MeHg due to its distinct protein contents and starch properties. Planting location can affect the Hg concentration in rice and THg bioaccessibility but has a limited impact on MeHg bioaccessibility. Based on these results, two macro factors(rice cultivar, planting location) are presumed to impact Hg bioaccessibility by how they affect micro factors(i.e., Hg forms).展开更多
The activation and functionalization of C-F bonds under mild conditions can serve as an important tool for organic syntheses including the modification of pharmaceuticals and agrochemicals and the synthesis of value-a...The activation and functionalization of C-F bonds under mild conditions can serve as an important tool for organic syntheses including the modification of pharmaceuticals and agrochemicals and the synthesis of value-added chemicals.However,owing to their high energy and low activity,C-F bonds are difficult to activate.展开更多
The widespread use of sodium p-perfluorous nonenoxybenzene sulfonate(OBS), a typical alternative to perfluorooctane sulfonate, has resulted in potential threats to the environment, but the adsorption behavior of OBS i...The widespread use of sodium p-perfluorous nonenoxybenzene sulfonate(OBS), a typical alternative to perfluorooctane sulfonate, has resulted in potential threats to the environment, but the adsorption behavior of OBS in soils has not yet been reported. In this study, the adsorption behaviors of OBS on five soils with different physicochemical properties were investigated. The rate of OBS adsorption was fast, and most of the OBS uptake was completed within 12 h. The good model fit of OBS adsorption to the pseudo-second-order and Elovich models indicated the occurrence of chemical adsorption. The adsorption isotherms of OBS on the soils were better described by the Freundlich model than by the Langmuir model, suggesting that the OBS adsorption sites on the soils were heterogeneous. This is possibly associated with various adsorption mechanisms including hydrophobic, π-π, hydrogen bonding, and electrostatic interactions,further confirmed by the good model fit to the D-R isotherm. Adsorption of OBS occurred on the soils, and the adsorption process was spontaneous and endothermic. In addition, the soils were more suitable for OBS adsorption at lower pH values due to the stronger electrostatic adsorption. The OBS adsorption on the soils decreased with the increase of soil depth from 0 to 30 cm. Moreover, the presence of organic matter and ammonia nitrogen in the soils was favorable for OBS adsorption, and these parameters decreased with increasing soil depth, making OBS adsorption less prominent in the deeper soil. This study indicates that OBS is easily enriched in surface soils, and that soil organic matter and ammonia nitrogen significantly affect OBS migration in soil.展开更多
基金supported by the Natural Science Foundation of Qinghai Province, China (No.2021-ZJ940Q)。
文摘In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.
基金supported by the National Natural Science Foundation of China(Grant Nos.42272103,92062221,42063009,U1812402)the Guizhou Provincial Science and Technology Projects(Grant No.Qiankehejichu–ZK[2022]common 213)the Higher Education Scientific Research Projects of the Education Department of Guizhou Province(Grant No.Qianjiaoji[2022]157).
文摘A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.
基金supported by the Key project of Chinese Academy of Sciences(Grant No.ZDRW-ZS-2020-2)Innovation Platform Program of Qinghai Province(2021-ZJ-T02),Key Laboratory Project of Qinghai Province(2022-ZJ-Y05)+1 种基金the Natural Science Foundation of China(Grant No.82171863)China Postdoctoral Science Foundation funded project(2021M701642).
文摘Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.
基金the National Natural Science Foundation of China(No.31901300)Natural Science Foundation of Guizhou Province+2 种基金China(No.(2019)1165)Science and Technology Foundation of Guizhou ProvinceChina(No.[2018]137,No.[2018]133)。
文摘Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests of northeastern China.Its seeds exhibit primary morphophysiological dormancy following dispersal in autumn,limiting natural or artificial regeneration:direct seeding and planting seedlings in spring.The aim of this study was to determine the optimum cold stratification temperature that induces germination to increase towards lower temperatures.Seeds from two populations(Changbaishan and Liangshui)were cold stratified at 0,5 and 10℃.Germination to incubation temperatures(10/5,20/10,25/15 and 30/20℃;14/10 h day/night)were determined after 2 and 4 weeks,and 5.5 and6.5 months of cold stratification.After 5.5 months,approximately 68-91%of seeds from both populations germinated at incubation temperatures of 25/15℃and 30/20℃,regardless of cold stratification temperatures.When the cold stratification temperature was reduced to 0℃and the period increased to 6.5 months,germination at 10/5℃significantly improved,reaching 37%and 64%for the Changbaishan and Liangshui populations,respectively.After 6.5 months of cold stratification,there was a significant linear regression between cold stratification temperatures and germination at10/5℃.The range in temperatures allowing for germination gradually expanded to include lower temperatures with decreasing cold stratification temperatures from 10 to 5℃and further to 0℃.
基金supported by the Natural Science Foundation of Qinghai Province,China(No.2021-ZJ940Q)the Open Project of State Key Laboratory of Plateau Ecology and Agriculture,Qinghai University(No.2022-ZZ-02)。
文摘As significant evidence of permafrost degradation,thermokarst lakes play an important role in the permafrost regions by regulating hydrology,ecology,and biogeochemistry.In the Sources Area of the Yellow River(SAYR),permafrost degradation has accelerated since the 1980s,and numerous thermokarst lakes have been discovered.In this paper,we use Sentinel-2 images to extract thermokarst lake boundaries and perform a regional-scale study on their geometry across the permafrost region in the SAYR.We also explored the spatiotemporal variations and potential drivers from the perspectives of the permafrost,climate,terrain and vegetation conditions.The results showed that there were 47,518 thermokarst lakes in 2021 with a total area of 190.22×106 m^(2),with an average size of 4,003.3 m^(2).The 44,928 ponds(≤10,000 m^(2))predominated the whole lake number(94.1%)but contributed to a small portion of the total lake area(28.8%).With 2,590 features(5.9%),small-sized(10,000 to 100,000 m^(2))and large-sized lakes(>100,000 m^(2))constituted up to 71.2%of the total lake area.Thermokarst lakes developed more significantly in warm permafrost regions than in cold permafrost areas;74.1%of lakes with a total area of 119.6×106 m^(2)(62.9%),were distributed in warm permafrost regions.Most thermokarst lakes were likely to develop within the elevation range of 4,500~4,800 m,on flat terrain(slope<10°),on SE and S aspects and in alpine meadow areas.The thermokarst lakes in the study region experienced significant shrinkage between 1990 and 2021,characterized by obvious lake drainage;the lake numbers decreased by 5418(56.1%),with a decreasing area of 58.63×106 m^(2)(49.0%).This shrinkage of the thermokarst lake area was attributable mainly to the intensified degradation of rich-ice permafrost thawing arising from continued climate warming,despite the wetting climatic trend.
基金funded by the National Natural Science Foundation of China(Grant No.31960277)the National Natural Science Foundation of China and Russian Foundation for Basic Research Cooperative Exchange Project(Grant Nos.32111530018,21-54-53031)+1 种基金the Natural Science Foundation of Qinghai Province of China(Grant No.2018-ZJ-932Q)supported by“1000 Talent”programs of Qinghai Province。
文摘Background:Himalayan Griffons(Gyps himalayensis),large scavenging raptors widely distributed in Qinghai-Tibetan Plateau,have evolved a remarkable ability to feed on carcasses without suffering any adverse effects.The gut microbiome plays an important role in animal physiological and pathological processes,and has also been found to play a health protective role in the vulture adaptation to scavenging.However,the microbial taxonomic diversity(including nonculturable and culturable microbes),functions,and metabolites related to Himalayan Griffons have not been fully explored.Methods:In the present study,the 28 fecal samples of the Himalayan Griffons and 8 carrion samples were collected and sequenced using high-throughput 16 S rRNA gene sequencing methods to analyze the composition and functional structures of the microbiomes.Twelve fecal samples of the Himalayan Griffons were analyzed using untargeted Liquid Chromatography Mass Spectroscopy(LC-MS)to identify metabolites.We used different culture conditions to grow Himalayan Griffons gut microbes.Inhibitory effects of gut beneficial bacteria on 5 common pathogenic bacteria were also tested using the Oxford cup method.Results:According to the results of the culture-independent method,a high abundance of four major phyla in Himalayan Griffons were identified,including Fusobacteria,Firmicutes,Bacteroidetes,and Proteobacteria.The most abundant genera were Fusobacterium,followed by Clostridium_sensu_stricto_1,Cetobacterium,Epulopiscium,and Bacteroides.The predicted primary functional categories of the Himalayan Griffons'gut microbiome were associated with carbohydrate and amino acid metabolism,replication and repair,and membrane transport.LC-MS metabolomic analysis showed a total of 154 metabolites in all the fecal samples.Cultivation yielded 184 bacterial isolates with Escherichia coli,Enterococcus faecium,Enterococcus hirae,and Paeniclostridium sordellii as most common isolates.Moreover,7 potential beneficial gut bacteria isolated showed certain inhibition to 5 common pathogenic bacteria.Conclusions:Our findings broaden and deepen the understanding of Himalayan Griffons'gut microbiome,and highlighted the importance of gut microbiome-mediated adaptation to scavenging habits.In particular,our results highlighted the protective role of gut beneficial bacteria in the Himalayan Griffons against pathogenic bacteria that appear in rotten food resources.
基金financially supported by the program of the National Natural Science Fund of China(Grant Nos.42002166,42063009)the Science and Technology Planning Project of Guizhou Province(Grant No.[2017]5788)Guizhou Provincial Fund Projects(Grant Nos.[2019]1065,[2020]1Y161)。
文摘With the aid of geophysical measurements,including seventeen two-dimensional(2 D)seismic lines and the well logging curves of well FGY1,the structure and reservoir characteristics of the Upper Ordovician–Lower Silurian strata in the Fenggang block,northern Guizhou Province,were analyzed thoroughly to identify desert areas and favorable intervals.The results show that Longmaxi-Wufeng is the most prospect-rich formation,consisting of a thick succession of overmature black shale,this formation remaining partially in the Suiyang,Fenggang and Jianchaxi synclines.The Longmaxi-Wufeng shale,especially the lower member,was deposited in a reducing low-energy environment with relatively high U content and a low Th/U value.In this shale,the organic matter type(sapropelic and humic-sapropelic),total organic carbon(TOC)content,gas content,gas adsorption capacity,vitrinite reflectance and brittle mineral content are profitable for shale gas preservation and development.The fractures of this shale were closed because of its high overburden pressure.The gas adsorption capacity of this shale increases with increasing TOC content and Ro.In the Longmaxi-Wufeng Formation at well FGY1,the most favorable intervals are in the depth ranges of 2312.4–2325.1 m and 2325.8–2331.1 m.
基金financially supported by the Strategic Priority Research Program(B)of Chinese Academy of Sciences(XDB18000000)National Natural Science Foundation of China(41773048)The Western Young Scholars Project(Class A)of Chinese Academy of Sciences。
文摘The Qulong porphyry Cu-Mo deposit,generated in the Miocene post-collisional extension environment of the Gangdese Copper(Molybdenum)Metallogenic Belt,is one of the largest porphyry Cu deposits in China.This study reports the noble gas isotopic compositions of volatiles released from fluid inclusion reserved in pyrite from the Qulong deposit.3He/4 He and 40Ar/36Ar ratios range from 0.54 to 1.015 Ra and 300-359,respectively.Concentrations of 4 He and 40Ar range from 1.77 to 2.62×10^(-8)cm^(3)STP and 1.7-34×10^(-8)cm^(3)STP,respectively.The isotopic composition of noble gases indicates that the ore-forming fluids of the Qulong Cu-Mo deposit were a mixture of fluid containing mantle component,which is exsolved from the porphyry magma,and crustal fluid characterized by atmospheric Ar and crustal radiogenic He.Theδ34S values of pyrite and molybdenite range from-0.52‰to 0.31‰,with an average of-0.12‰,indicating a magmatic origin.More mantle components were involved in the Cu-Mo deposit than in the Mo-Cu deposit in the Qulong-Jiama ore-district.
基金This research was funded by the National Natural Science Foundation of China to Xiaoling Tian(No.31901237)it was supported by the Young Academic and Technical Leader Raising Foundation of Yunnan Province to Yongpeng Ma(No.2018HB066).
文摘Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing on seed dispersal and germination of B.hancei,we measured the dispersal distance at varying wind speeds and release heights,falling duration from different release heights,floating duration on still water,rates of imbibition of water,and drying and soil adherence to seeds.Germination experiments were conducted on intact and de-winged seeds immediately after harvest.The wing increased the falling duration in still air and the floating ability on water.Dispersal distance of winged and de-winged seeds did not differ at a wind speed of 2.8 m s1,but at 3.6 and 4.0 m s1 dispersal distances were greater for de-winged than for winged seeds.Seed wing had little effect of absorption and retention of water,but significantly increased soil adherence to the seeds.Mature seeds were non-dormant and germinated to over 90%with a mean germination time of about 10 days.By combining the environmental conditions in karst habitat with the seed traits of B.hancei,we conclude that dispersal and germination of winged seeds are adapted to the precipitation seasonality in heterogeneous habitats absence of soil.
基金Supported by the Guizhou Provincial Education Department of Education's Youth Science and Technology Project Fund Grant No.161/2016(Q-J-H-KY)the Science and Technology Planning Project of Guizhou Science and Technology Department Project Fund grant No.1074/2018(Qian-ke-he-basic)
文摘Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.
基金supported by Youth Project of Science and Technology Research Program of Chongqing Education Commission of China(No.KJQN202101201)。
文摘In order to explore the influence of wet nitrogen(N)deposition on N output in watersheds,this study selected a typical small watershed(Chenjiagou,CJG)in the Three Gorges Reservoir(TGR)area based on one-year observation of rainfallrunoff N forms.Characteristics and sources of N output were clarified by chemical statistics and isotopic abundance,and the contribution of N deposition to the N output was quantified by the output coefficient method.The N flux of wet deposition was estimated at 18.53 kg N ha^(-1) yr^(-1),and originated mostly from agricultural activities.Watershed N was significantly accumulated from upper to lower reaches due to frequent human activities.Seasonal changes of riverine N were strongly affected by chemical fertilizer,with the highest concentration in spring and the lowest in winter.Nitrate was mainly derived from chemical fertilizer,accounting for 38.83% of all sources.N concentration in processes of different rainfall events had a hysteresis effect corresponding to the flow rate.Three rainfall events greatly changed DTN(Dissolved total N)outputs:rainstorm caused 91.26 kg DTN output,which was 11 times that of moderate rain(8.46 kg)and 4 times that of heavy rain(20.80 kg).N deposition contributed 19.89% of riverine N output in the watershed.The results can provide theoretical support for the control of N pollution in the TGR area.
基金National Natural Science Foundation of China(41263006)Science and Technology Support Project of Guizhou Province(Qiankehe Support[2020]No.4Y017).
文摘Firstly,the advantages and disadvantages of constructed wetlands for treating rural domestic sewage are introduced.Secondly,the types of constructed wetland plants are introduced.Thirdly,the suitability of using medicinal wetland plants to treat rural domestic sewage is analyzed.Fourthly,the principles of selecting wetland plants with medicinal value are studied.Finally,commonly used constructed wetland plants and their medicinal value are introduced.
基金Supported by Science and Technology Top Talent Support Project of Guizhou Provincial Department of Education (QIANJIAOHE KY ZI[2018]044)Innovation and Entrepreneurship Training Program for College Students(201510672007,201710672011)。
文摘[Objectives] The research aimed to study the effect of sludge extract on the growth of Zinnia elegans, and evaluate its possibility of application. [Methods] Z. elegans was taken as research object, and the effect of sludge extract on the growth indicators of Z. elegans was studied. [Results] The sludge extract can obviously promote the growth of Z. elegans, and the growth indicators were significantly improved when compared with the control group. The application effect was close to that of foliar fertilizer purchased in the market. In each treatment group, the low concentration of sludge extract did not significantly promote the growth of Z. elegans, while too high concentration could inhibit its growth, and the optimal dilution ratio was 600 times. [Conclusions] Further preparation of amino acid foliar fertilizer from sludge extract and its application in planting garden plants can realize the resource utilization of sludge and has a good development and application prospect.
基金supported by the National Natural Science Foundation of China (No.22166012)Guizhou Provincial Science and Technology Projects (No.[2020]1Z007)。
文摘Triclosan(TCS)has been manufactured as an antibacterial compound for half a century.Currently,it is widely used in various personal care products;however,its potential adverse effects raise a lot of attention.Here,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of TCS.We discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic fibrosis.Further study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,respectively.Accompanied by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron disorder.Not only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to ferroptosis.Additional study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,individually.Taken together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin axis.Meanwhile,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver fibrosis.Ferriprox■,an iron scavenger,significantly ameliorates TCS-induced liver fibrosis.In summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also displayed.The significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.
基金financially supported by the National Natural Science Foundation of China (Nos. 31670473 and 42107091)
文摘Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river ecosystems.Previous views suggested that labile components were dominantly consumed by microbial metabolism.Here we provide new observations that a part of recalcitrant compounds largely contribute to riverine DOM biodegradation.The excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component variability during DOM incubation.Humic-like and tryptophan-like DOM are the primary components of riverine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,respectively.After 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are observed.Elevated temperature enhances the decomposition of ultraviolet humiclike substance and further stimulates labile DOM bio-mineralization into carbon dioxide.Meanwhile,averaged proportions of amino acid compositions(peak B and T)markedly increase(p<0.05)as the humic-like compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight compounds.The findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps”,contributing to a new understanding of carbon cycling for the UN Sustainable Development Goal.
基金supported by the National Natural Science Foundation of China(31901300,31960636)Natural Science Foundation of Guizhou Province((2019)1165)and Science and Technology Foundation of Guizhou Province([2018]137).
基金This paper is funded by National Key Research and Development Program of China(No.2018YFC1900904)Postgraduate Research Fund of Guizhou Province(No.YJSCXJH(2019)055).
文摘Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited condi-tions.Preparation methods contribute to biochar properties,which are widely concerned in the agronomic and environmental benefits of agro-ecosystems.This research aims to use bibliometrics methods to comprehensively and objectively analyze the research trends in the global biochar production field from 2006 to 2019 based on the Web of Science Core Collection database.The results showed that 1434 papers related to biochar preparation were published,which gradually increased each year.The research topics were diversified,which were mainly divided into“Environmental Sciences and Ecology,”“Engineering”and“Agriculture”.Moreover,Bioresource Technology was the most published journal contained biochar preparation.Authors from China had the most publications,followed by the US,Australia and the UK.Meanwhile,Yong Sik Ok from Korea University contributed most of the publications and had the highest H-index.Keywords analysis indicated that biochar preparation by pyrolysis was a current hotspot,of which microwave and hydrothermal were a future research trend.Besides,gasification would be used to develop new biomass energy.Biochar has the characteristics of high pH,high specific surface area,high carbon content,and rich functional groups.It is mainly used in soil improvement,water pollutant adsorption,carbon sequestration and emission reduction,and energy storage materials,etc.Furthermore,raw materials,pyrolysis temperature and pyrolysis time will also affect its characteristics and applications.It is expected that this study may provide insight into the future research interests regarding biochar preparation.
基金supported by the research fund of Guizhou Minzu University (No. GZMUZK[2021]YB14)the open research fund of Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education of the People’s Republic of China (No. QJH-KY[2020]247)。
文摘Mercury(Hg) in rice is drawing mounting concern since methylmercury(MeHg) was found capable of accumulating in rice. In-vitro bioaccessibility is a feasible and reliable method to assess the health effects of Hg in rice and has been utilized in a number of studies. This study was done to investigate the impact of cultivar, planting location, and cooking on the total mercury(THg) and MeHg bioaccessibility of rice, for which multiple statistical analysis methods were used to analyze the significance of their effects. The THg concentrations of rice samples taken from non-Hg contaminated areas of China were all below 15 ng/g and their MeHg concentrations were below 2 ng/g. Cooking could significantly reduce the MeHg bioaccessibility of rice because the MeHg was mainly combined with protein and the protein will be denatured during the cooking process, and then the denatured MeHg is difficult to be dissolved into the liquid phase. Indica-and japonica-type rice cultivars did not show significant differentiation in either the concentration of Hg or its bioaccessibility. However, the glutinous rice type differed significantly from the above rice types, and it showed greater bioaccessibility of THg and MeHg due to its distinct protein contents and starch properties. Planting location can affect the Hg concentration in rice and THg bioaccessibility but has a limited impact on MeHg bioaccessibility. Based on these results, two macro factors(rice cultivar, planting location) are presumed to impact Hg bioaccessibility by how they affect micro factors(i.e., Hg forms).
基金We acknowledge financial support from the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(19KJB150020)the construction project of the Key Laboratory of State Ethnic Affairs Commission([2020]No.91 of DDA office).Special thanks to Chen Hong,Jiangsu College of Tourism,for polishing the language.
文摘The activation and functionalization of C-F bonds under mild conditions can serve as an important tool for organic syntheses including the modification of pharmaceuticals and agrochemicals and the synthesis of value-added chemicals.However,owing to their high energy and low activity,C-F bonds are difficult to activate.
基金supported by the Fundamental Research Project of Qinghai Province (No.2019-ZJ-935Q),Chinathe Beijing Natural Science Foundation (No.8184079),China。
文摘The widespread use of sodium p-perfluorous nonenoxybenzene sulfonate(OBS), a typical alternative to perfluorooctane sulfonate, has resulted in potential threats to the environment, but the adsorption behavior of OBS in soils has not yet been reported. In this study, the adsorption behaviors of OBS on five soils with different physicochemical properties were investigated. The rate of OBS adsorption was fast, and most of the OBS uptake was completed within 12 h. The good model fit of OBS adsorption to the pseudo-second-order and Elovich models indicated the occurrence of chemical adsorption. The adsorption isotherms of OBS on the soils were better described by the Freundlich model than by the Langmuir model, suggesting that the OBS adsorption sites on the soils were heterogeneous. This is possibly associated with various adsorption mechanisms including hydrophobic, π-π, hydrogen bonding, and electrostatic interactions,further confirmed by the good model fit to the D-R isotherm. Adsorption of OBS occurred on the soils, and the adsorption process was spontaneous and endothermic. In addition, the soils were more suitable for OBS adsorption at lower pH values due to the stronger electrostatic adsorption. The OBS adsorption on the soils decreased with the increase of soil depth from 0 to 30 cm. Moreover, the presence of organic matter and ammonia nitrogen in the soils was favorable for OBS adsorption, and these parameters decreased with increasing soil depth, making OBS adsorption less prominent in the deeper soil. This study indicates that OBS is easily enriched in surface soils, and that soil organic matter and ammonia nitrogen significantly affect OBS migration in soil.
