[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yin...[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources.展开更多
The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual applicatio...The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual application of AHFO technology to the water content measurement of in situ soil.However,all existing in situ applications of AHFO technology fail to consider the effect of soilesensor contact quality on water content measurements,limiting potential for the wider application of AHFO technology.To address this issue,the authors propose a method for determining the soilesensor thermal contact resistance based on the principle of an infinite cylindrical heat source.This is then used to establish an AHFO water content measurement technology that considers the thermal contact resistance.The reliability and validity of the new measurement technology are explored through a laboratory test and a field case study,and the spatial-temporal evolution of the soil water content in the case is revealed.The results demonstrate that method for determining the soilesensor thermal contact resistance is highly effective and applicable to all types of soils.This method requires only the moisture content,dry density,and thermal response of the in situ soil to be obtained.In the field case,the measurement error of soil water content between the AHFO method,which takes into account the thermal contact resistance,and the neutron scattering method is only 0.011.The water content of in situ soil exhibits a seasonal variation,with an increase in spring and autumn and a decrease in summer and winter.Furthermore,the response of shallow soils to precipitation and evaporation is significant.These findings contribute to the enhancement of the accuracy of the AHFO technology in the measurement of the water content of in situ soils,thereby facilitating the dissemination and utilization of this technology.展开更多
Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and...Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and efficient electron transfer.Herein,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for photo-biocatalysis.With SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic systems.Since SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.展开更多
We introduce the structure of a radio astronomy phased array feeds(PAF)beamforming demonstrator.In a laboratory environment,we have demonstrated beamforming on a received 1.25 GHz sinusoidal signal and used digital we...We introduce the structure of a radio astronomy phased array feeds(PAF)beamforming demonstrator.In a laboratory environment,we have demonstrated beamforming on a received 1.25 GHz sinusoidal signal and used digital weighting techniques to plot the 2D pattern of the PAF.The radio frequency part of the demonstrator includes a 4×4 linearly polarized microstrip antenna array,all of which is connected in series with a low-noise amplifier.The signals from the central 4×2 array elements are injected into a radio frequency system-on-chip digital board,which can receive eight inputs with a bandwidth of 512 MHz.Combining the principle of undersampling,the beamforming is completed at a frequency of 1.25 GHz for the offline data,and a 2D image of the beam is plotted using beam scanning technology.展开更多
A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature a...A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps.展开更多
The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal m...The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal model is to add the coupling coefficient among elements of PAF to the conventional array signal model. Then the subspace projection(SP) algorithm is used to cancel RFI from the correlation matrix of the signal, and finally, the 2D power image is drawn. The power variation of signal-of-interest direction and RFI direction before and after using the SP algorithm is analyzed. The new signal model and simulation strategy can be used to test and verify the beamformer.展开更多
Morchella septimelata polysaccharide(MSP)possesses multiple biological activities.In this study,double enzyme method was used to extract polysaccharides from Morchella septimelata.The basis of single factor experiment...Morchella septimelata polysaccharide(MSP)possesses multiple biological activities.In this study,double enzyme method was used to extract polysaccharides from Morchella septimelata.The basis of single factor experiment and response surface design was used to optimize the extraction process of polysaccharides.The optimal extraction conditions of polysaccharide were as follows:extraction time 2 h,extraction temperature 40.5℃,solid-liquid ratio 1:15(w/v),and the amount of double enzyme(cellulase:β-glucanase,mass ratio 1:2)2.0%.Under these conditions,the extraction yield of polysaccharide reached(14.86±0.12)%.展开更多
Objective:We investigated the relation between man papillomavirus(HPV)integration status and the immediate risk of cervical intraepithelial neoplasia(CIN),as well as the triage strategy based on HPV integration test.M...Objective:We investigated the relation between man papillomavirus(HPV)integration status and the immediate risk of cervical intraepithelial neoplasia(CIN),as well as the triage strategy based on HPV integration test.Methods:4086 women aged 20 to 65 years in China were enrolled in 2015 for a prospective,population-based,clinical observational study to evaluate the triage performance of HPV integration.Cervical exfoliated cells were collected for HPV testing and cytologic test.If high-risk HPV was positive,HPV integration test was performed at baseline,2-year and 5-year follow-up.Results:At baseline,HPV integration was positively correlated with the severity of cervical pathology,ranging from 5.0%(15/301)in normal diagnosis,6.9%(4/58)in CIN1,31.0%(9/29)in CIN2,70%(14/20)in CIN3,and 100%(2/2)in cervical cancer(P<0.001).Compared with cytology,HPV integration exhibits comparable sensitivity and negative predictive value for the diagnosis of CIN3+,higher specificity(92.8%[90.2%-95.4%]vs.75.5%[71.2%-79.8%],P<0.001)and higher positive predictive value(36.4%[22.1%-50.6%]vs.15.2%[8.5%-21.8%],P<0.001).HPV integration testing strategy yielded a significantly lower colposcopy referral rate than cytology strategy(10.7%[44/410]vs.27.3%[112/410],P<0.001).The HPV integration-negative group exhibited the lowest immediate risk for CIN3+(1.6%)and accounted for the largest proportion of the total population(89.3%),when compared with the normal cytology group(risk,1.7%;proportion,72.7%).Conclusion:As a key molecular basis for the development of cervical cancer,HPV integration might be a promising triage strategy for HPV-positive patients.展开更多
The sea surface escort formation faces various threats in reality. For example, suicide boats may carry explosives or other dangerous items, aiming to cause maximum damage by colliding or detonating escort targets. Si...The sea surface escort formation faces various threats in reality. For example, suicide boats may carry explosives or other dangerous items, aiming to cause maximum damage by colliding or detonating escort targets. Since suicide boats have a certain degree of concealment, it is necessary to establish a threat assessment algorithm to timely identify and respond to such fast and concealed threats. This paper establishes a threat assessment model that considers the instantaneous and historical states of the target. The instantaneous state of the target takes into account six evaluation indicators, including target category, target distance, target heading, target speed, collision risk, and ship automatic identification system(AIS) recognition status;in terms of historical state information mining, a target typical intention recognition method based on graph neural network is proposed to achieve end-to-end target typical intention recognition. Furthermore, this paper introduces a multi-attribute decision analysis method to weight the evaluation indicators, improves the relative closeness calculation method between different evaluation schemes and positive and negative ideal schemes, and determines the target threat ranking based on relative closeness. Based on Unity3D, a set of unmanned boat confrontation simulation system is designed and developed, and typical intention recognition data sets and threat assessment scenario simulation data are generated through real-life confrontation. Comparative analysis shows that the threat assessment model in this paper can accurately and timely detect raid target threats and give scientific and reasonable target threat ranking results.展开更多
The pollutants in urban storm runoff, which lead to an non-point source contamination of water environment around cities, are of great concems. The distributions of typical contaminants and the variations of their spe...The pollutants in urban storm runoff, which lead to an non-point source contamination of water environment around cities, are of great concems. The distributions of typical contaminants and the variations of their species in short term storm runoff from different land surfaces in Xiamen City were investigated. The concentrations of various contaminants, including organic matter, nutrients （i.e., N and P） and heavy metals, were significantly higher in parking lot and road runoff than those in roof and lawn runoff. The early runoff samples from traffic road and parking lot contained much high total nitrogen （TN 6-19 mg/L） and total phosphorus （TP 1-3 mg/L）. A large proportion （around 60%） of TN existed as total dissolved nitrogen （TDN） species in most runoff. The percentage of TDN and the percentage of total dissolved phosphorus remained relatively stable during the rain events and did not decrease as dramatically as TN and TP. In addition, only parking lot and road runoff were contaminated by heavy metals, and both Pb （25-120 μg/L） and Zn （0.1-1.2 mg/L） were major heavy metals contaminating both runoff. Soluble Pb and Zn were predominantly existed as labile complex species （50%-99%）, which may be adsorbed onto the surfaces of suspended particles and could be easily released out when pH decreased. This would have the great impact to the environment.展开更多
The Yao'an Pb–Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang–Ailaoshan alkaline porphyry–related polymetallic intrusive belt. This complex suite o...The Yao'an Pb–Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang–Ailaoshan alkaline porphyry–related polymetallic intrusive belt. This complex suite of rock bodies includes a vein of pseudoleucite porphyry within deposits of syenite porphyry and trachyte.The pseudoleucite is characterized by a variable greyish,greyish-white, and greyish-green porphyritic texture. Phenocrysts are mainly pseudoleucite with small amounts of alkali feldspar and biotite. In an intense event, leucite phenocrysts altered to orthoclase, kaolinite, and quartz.Both the pseudoleucite porphyry and the syenite porphyry samples were typical alkali-rich, K-rich, al-rich rocks with high LaN/YbNratios; enriched in light rare earth elements and large-ion lithophile elements, and depleted in high field strength elements; and with strongly negative Ta, Nb, and Ti(TNT) anomalies and slightly negative Eu anomalies—all characteristics of subduction-zone mantle-derived rock.We obtained a LA-ICP-MS zircon U–Pb age of 34.1 ± 0.3 Ma(MSWD = 2.4), which is younger than the established age of the Indian and Eurasian Plate collision.The magma derived from a Type-II enriched mantle formed in a post-collisional plate tectonic setting. The geochemical characteristics of the Yao'an pseudoleucite porphyry are powerful evidence that the porphyry'sdevelopment was closely linked to the Jinshajiang–Ailaoshan fault and to the Indian-Eurasian collision.展开更多
基金Supported by High-level Training Project of Huanggang Normal University in 2021(202108504).
文摘[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources.
基金supported by the National Natural Science Foundation of China(Grant Nos.42307189 and 42030701)the China Postdoctoral Science Foundation(Grant No.2023M740974).
文摘The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual application of AHFO technology to the water content measurement of in situ soil.However,all existing in situ applications of AHFO technology fail to consider the effect of soilesensor contact quality on water content measurements,limiting potential for the wider application of AHFO technology.To address this issue,the authors propose a method for determining the soilesensor thermal contact resistance based on the principle of an infinite cylindrical heat source.This is then used to establish an AHFO water content measurement technology that considers the thermal contact resistance.The reliability and validity of the new measurement technology are explored through a laboratory test and a field case study,and the spatial-temporal evolution of the soil water content in the case is revealed.The results demonstrate that method for determining the soilesensor thermal contact resistance is highly effective and applicable to all types of soils.This method requires only the moisture content,dry density,and thermal response of the in situ soil to be obtained.In the field case,the measurement error of soil water content between the AHFO method,which takes into account the thermal contact resistance,and the neutron scattering method is only 0.011.The water content of in situ soil exhibits a seasonal variation,with an increase in spring and autumn and a decrease in summer and winter.Furthermore,the response of shallow soils to precipitation and evaporation is significant.These findings contribute to the enhancement of the accuracy of the AHFO technology in the measurement of the water content of in situ soils,thereby facilitating the dissemination and utilization of this technology.
基金the financial support from the National Natural Science Foundation of China (22274102 and 22325403)the Fundamental Research Funds from Sichuan University (2022SCUNL104)the Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(2022A02)
文摘Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and efficient electron transfer.Herein,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for photo-biocatalysis.With SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic systems.Since SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.
基金funded by the National Key R&D Program of China under No.2022YFC2205300the National Natural Science Foundation of China(NSFC,grant Nos.12073067 and 11973078)the Chinese Academy of Sciences(CAS)“Light of West China”Program under No.2022-XBQNXZ012 and No.2020-XBQNXZ-018。
文摘We introduce the structure of a radio astronomy phased array feeds(PAF)beamforming demonstrator.In a laboratory environment,we have demonstrated beamforming on a received 1.25 GHz sinusoidal signal and used digital weighting techniques to plot the 2D pattern of the PAF.The radio frequency part of the demonstrator includes a 4×4 linearly polarized microstrip antenna array,all of which is connected in series with a low-noise amplifier.The signals from the central 4×2 array elements are injected into a radio frequency system-on-chip digital board,which can receive eight inputs with a bandwidth of 512 MHz.Combining the principle of undersampling,the beamforming is completed at a frequency of 1.25 GHz for the offline data,and a 2D image of the beam is plotted using beam scanning technology.
基金This work was supported by the National Key Research and Development Program of China(2022YFB2802801)the National Natural Science Foundation of China(61834008,U21A20493)+1 种基金the Key Research and Development Program of Jiangsu Province(BE2020004,BE2021008-1)the Suzhou Key Laboratory of New-type Laser Display Technology(SZS2022007).
文摘A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps.
基金funded by the National Key R&D Program of China under No. 2022YFC2205300the National Natural Science Foundation of China (12073067)the Chinese Academy of Sciences (CAS)“Light of West China” Program under No. 2022-XBQNXZ-012。
文摘The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal model is to add the coupling coefficient among elements of PAF to the conventional array signal model. Then the subspace projection(SP) algorithm is used to cancel RFI from the correlation matrix of the signal, and finally, the 2D power image is drawn. The power variation of signal-of-interest direction and RFI direction before and after using the SP algorithm is analyzed. The new signal model and simulation strategy can be used to test and verify the beamformer.
基金Supported by The Key Research and Development Program of Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization(202141204)The 2024 Huanggang Municipal Level Science and Technology Innovation Special Fund(YBXM20240031).
文摘Morchella septimelata polysaccharide(MSP)possesses multiple biological activities.In this study,double enzyme method was used to extract polysaccharides from Morchella septimelata.The basis of single factor experiment and response surface design was used to optimize the extraction process of polysaccharides.The optimal extraction conditions of polysaccharide were as follows:extraction time 2 h,extraction temperature 40.5℃,solid-liquid ratio 1:15(w/v),and the amount of double enzyme(cellulase:β-glucanase,mass ratio 1:2)2.0%.Under these conditions,the extraction yield of polysaccharide reached(14.86±0.12)%.
基金supported by the National Nature Science Foun-dation of China(grant numbers:82141106,81630060)the National Key Research and Development Program of China(grant number:2021YFC2701204)+2 种基金Key Technology R&D Program of Hubei(grant num-ber:2024BCB057)Panyu District Science and Technology Plan Project(grant number:2020-Z04-014)Guangzhou Health Science and Tech-nology Project(grant number:20221A011118).
文摘Objective:We investigated the relation between man papillomavirus(HPV)integration status and the immediate risk of cervical intraepithelial neoplasia(CIN),as well as the triage strategy based on HPV integration test.Methods:4086 women aged 20 to 65 years in China were enrolled in 2015 for a prospective,population-based,clinical observational study to evaluate the triage performance of HPV integration.Cervical exfoliated cells were collected for HPV testing and cytologic test.If high-risk HPV was positive,HPV integration test was performed at baseline,2-year and 5-year follow-up.Results:At baseline,HPV integration was positively correlated with the severity of cervical pathology,ranging from 5.0%(15/301)in normal diagnosis,6.9%(4/58)in CIN1,31.0%(9/29)in CIN2,70%(14/20)in CIN3,and 100%(2/2)in cervical cancer(P<0.001).Compared with cytology,HPV integration exhibits comparable sensitivity and negative predictive value for the diagnosis of CIN3+,higher specificity(92.8%[90.2%-95.4%]vs.75.5%[71.2%-79.8%],P<0.001)and higher positive predictive value(36.4%[22.1%-50.6%]vs.15.2%[8.5%-21.8%],P<0.001).HPV integration testing strategy yielded a significantly lower colposcopy referral rate than cytology strategy(10.7%[44/410]vs.27.3%[112/410],P<0.001).The HPV integration-negative group exhibited the lowest immediate risk for CIN3+(1.6%)and accounted for the largest proportion of the total population(89.3%),when compared with the normal cytology group(risk,1.7%;proportion,72.7%).Conclusion:As a key molecular basis for the development of cervical cancer,HPV integration might be a promising triage strategy for HPV-positive patients.
基金funded by by the National Natural Science Foundation of China under Grant 52101377。
文摘The sea surface escort formation faces various threats in reality. For example, suicide boats may carry explosives or other dangerous items, aiming to cause maximum damage by colliding or detonating escort targets. Since suicide boats have a certain degree of concealment, it is necessary to establish a threat assessment algorithm to timely identify and respond to such fast and concealed threats. This paper establishes a threat assessment model that considers the instantaneous and historical states of the target. The instantaneous state of the target takes into account six evaluation indicators, including target category, target distance, target heading, target speed, collision risk, and ship automatic identification system(AIS) recognition status;in terms of historical state information mining, a target typical intention recognition method based on graph neural network is proposed to achieve end-to-end target typical intention recognition. Furthermore, this paper introduces a multi-attribute decision analysis method to weight the evaluation indicators, improves the relative closeness calculation method between different evaluation schemes and positive and negative ideal schemes, and determines the target threat ranking based on relative closeness. Based on Unity3D, a set of unmanned boat confrontation simulation system is designed and developed, and typical intention recognition data sets and threat assessment scenario simulation data are generated through real-life confrontation. Comparative analysis shows that the threat assessment model in this paper can accurately and timely detect raid target threats and give scientific and reasonable target threat ranking results.
基金supported by the Knowledge Innovation Program of Chinese Academy of Sciences for Young Scientists in Frontier Research (No.07l4161b10)the National Natural Science Foundation of China (No.20807033)
文摘The pollutants in urban storm runoff, which lead to an non-point source contamination of water environment around cities, are of great concems. The distributions of typical contaminants and the variations of their species in short term storm runoff from different land surfaces in Xiamen City were investigated. The concentrations of various contaminants, including organic matter, nutrients （i.e., N and P） and heavy metals, were significantly higher in parking lot and road runoff than those in roof and lawn runoff. The early runoff samples from traffic road and parking lot contained much high total nitrogen （TN 6-19 mg/L） and total phosphorus （TP 1-3 mg/L）. A large proportion （around 60%） of TN existed as total dissolved nitrogen （TDN） species in most runoff. The percentage of TDN and the percentage of total dissolved phosphorus remained relatively stable during the rain events and did not decrease as dramatically as TN and TP. In addition, only parking lot and road runoff were contaminated by heavy metals, and both Pb （25-120 μg/L） and Zn （0.1-1.2 mg/L） were major heavy metals contaminating both runoff. Soluble Pb and Zn were predominantly existed as labile complex species （50%-99%）, which may be adsorbed onto the surfaces of suspended particles and could be easily released out when pH decreased. This would have the great impact to the environment.
基金funded by National Natural Science Foundation of China (Grant Number:41102049)Mineral Resources Prediction and Evaluation Engineering Laboratory of Yunnan Provincethe Program of Provincial and University Innovation Team
文摘The Yao'an Pb–Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang–Ailaoshan alkaline porphyry–related polymetallic intrusive belt. This complex suite of rock bodies includes a vein of pseudoleucite porphyry within deposits of syenite porphyry and trachyte.The pseudoleucite is characterized by a variable greyish,greyish-white, and greyish-green porphyritic texture. Phenocrysts are mainly pseudoleucite with small amounts of alkali feldspar and biotite. In an intense event, leucite phenocrysts altered to orthoclase, kaolinite, and quartz.Both the pseudoleucite porphyry and the syenite porphyry samples were typical alkali-rich, K-rich, al-rich rocks with high LaN/YbNratios; enriched in light rare earth elements and large-ion lithophile elements, and depleted in high field strength elements; and with strongly negative Ta, Nb, and Ti(TNT) anomalies and slightly negative Eu anomalies—all characteristics of subduction-zone mantle-derived rock.We obtained a LA-ICP-MS zircon U–Pb age of 34.1 ± 0.3 Ma(MSWD = 2.4), which is younger than the established age of the Indian and Eurasian Plate collision.The magma derived from a Type-II enriched mantle formed in a post-collisional plate tectonic setting. The geochemical characteristics of the Yao'an pseudoleucite porphyry are powerful evidence that the porphyry'sdevelopment was closely linked to the Jinshajiang–Ailaoshan fault and to the Indian-Eurasian collision.
