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滇西芦子园远程矽卡岩Pb-Zn-Fe(Cu)多金属矿床流体包裹体初探及矿床成因探讨 被引量:19
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作者 邓明国 陈伟 +5 位作者 王学武 刘凤祥 管申进 卢映祥 余海军 赵发 《岩石学报》 SCIE EI CAS CSCD 北大核心 2018年第5期1239-1257,共19页
滇西镇康芦子园是"三江"成矿带保山地块内迄今发现的唯一超大型Pb-Zn-Fe(Cu)多金属矿床,是区内系列同类层控热液铅锌矿床的典型代表。矿体呈似层状、脉状及透镜状产于寒武系碳酸盐岩建造的矽卡岩和大理岩层间破碎带,矿石构造... 滇西镇康芦子园是"三江"成矿带保山地块内迄今发现的唯一超大型Pb-Zn-Fe(Cu)多金属矿床,是区内系列同类层控热液铅锌矿床的典型代表。矿体呈似层状、脉状及透镜状产于寒武系碳酸盐岩建造的矽卡岩和大理岩层间破碎带,矿石构造以条带状、浸染状和脉状-网脉状为主要特征;围岩蚀变复杂、分带明显,由下至上依次为石榴子石-透辉石-透闪石-阳起石化带→绿泥石-绿帘石-阳起石-蔷薇辉石化带→碳酸盐-大理岩化带。矿床成矿流体从早期到晚期经历了多个矿化阶段。本文选取了该矿床早矽卡岩阶段、晚矽卡岩阶段、石英硫化物阶段和石英碳酸盐阶段的多种脉石矿物及闪锌矿进行了系统的流体包裹体研究。结果显示,早矽卡岩阶段发育微溶CO_2富液相和纯液相水溶液包裹体,并含大量K^+、Na^+、Ca^(2+)、F^-和Cl^-和少量SO_4^(2-),气相成分主要为H_2O、CO_2及少量CH_4和N_2,包裹体均一温度为233.6~315.6℃,盐度为10.6%~17.6%NaCleqv;晚矽卡岩阶段发育含CO_2和子矿物三相包裹体,均一温度214.9~388.0℃,盐度5.9%~16.4%NaCleqv;石英硫化物阶段发育含CO_2的水溶液包裹体,气相成分为CH_4、H_2O和少量CO_2,均一温度150.0~285.0℃,盐度为2.5%~13.8%NaCleqv;石英碳酸盐阶段为单一成分的水溶液包裹体,均一温度为105.0~187.5℃,盐度为0.5%~12.3%NaCleqv。结合H-O同位素研究表明,成矿流体最初来源于具中高温、中高盐度、高K、Na,富CO_2、Cl、F等特征的深部岩浆热液,在石英硫化物阶段开始有大气降水混入,演化为中阶段中低温、低盐度、贫CO_2的热液流体,至成矿晚阶段转化为以大气降水占主导。该矿床成矿环境的改变、流体混合以及流体的沸腾作用可能是导致成矿物质富集沉淀的重要机制。综合矿床地质特征、成矿流体包裹体和HO同位素研究认为,该矿床为与陆陆碰撞造山和深部隐伏岩体有关的远程矽卡岩成矿系统。 展开更多
关键词 流体包裹体 成矿流体 H-O同位素 滇西芦子园 Pb-Zn-Fe(Cu)多金属矿床 远程矽卡岩 大陆碰撞
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首届(2005)’PBS&J-清华大学’ITS学生论文竞赛征稿通知
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《ITS通讯》 2005年第2期9-10,共2页
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中国荷斯坦牛繁殖性状的基因型与环境互作
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作者 师睿 李珊珊 +5 位作者 张海亮 路海博 闫青霞 张毅 陈绍祜 王雅春 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第9期3968-3977,共10页
旨在估计奶牛繁殖性状在不同地区的遗传参数,检测同一繁殖性状在不同地区之间的基因型与环境互作(G×E)效应。本研究利用全国6个地区2064个牧场2005至2022年的荷斯坦牛群繁殖记录,计算了2个重要繁殖性状:初产日龄(AFC)和产犊间隔(C... 旨在估计奶牛繁殖性状在不同地区的遗传参数,检测同一繁殖性状在不同地区之间的基因型与环境互作(G×E)效应。本研究利用全国6个地区2064个牧场2005至2022年的荷斯坦牛群繁殖记录,计算了2个重要繁殖性状:初产日龄(AFC)和产犊间隔(CI),共包含1787590和2476422条表型数据。同时对该原始表型数据进行详细的质控和分组。随后,通过BLUPF90软件的airemlf90模块利用单性状动物模型和重复力模型对6个地区的2个繁殖性状进行了遗传分析,使用双性状动物和重复力模型估计同一性状不同地区之间的遗传相关,作为基因型与环境之间效应(G×E)的检测指标。结果表明,研究所设定的质控条件能够剔除分布异常的表型值;AFC的遗传力较高且在地区间差异较大(0.06~0.40),而CI的遗传力较低且各地区间差异较小(0.02~0.04);在大多数地区组合下,2个繁殖性状皆检测到了显著的G×E效应(P<0.05)。综上,同一繁殖性状在不同地区的遗传表现存在差异,且部分区域之间存在显著的G×E效应。因此,对我国奶牛繁殖性状进行遗传改良时需考虑区域性差异及G×E效应对遗传进展的影响。 展开更多
关键词 奶牛 繁殖性状 遗传参数 基因型与环境互作
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Pb^(2+)和Fe^(3+)对三唑磷在水环境中光降解影响研究
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作者 陈容 孟春霞 周立敏 《海洋湖沼通报》 CSCD 北大核心 2021年第4期121-126,共6页
本文探索研究了Pb^(2+)和Fe^(3+)在不同水溶液中对三唑磷的光降解影响。结果表明:在300 W高压汞灯照射下,在去离子水中,不同浓度的Pb^(2+)对三唑磷的光降解均起抑制作用。在人工海水中,0.01 mg/L和0.1 mg/L的Pb^(2+)对三唑磷的光降解有... 本文探索研究了Pb^(2+)和Fe^(3+)在不同水溶液中对三唑磷的光降解影响。结果表明:在300 W高压汞灯照射下,在去离子水中,不同浓度的Pb^(2+)对三唑磷的光降解均起抑制作用。在人工海水中,0.01 mg/L和0.1 mg/L的Pb^(2+)对三唑磷的光降解有抑制作用,而1 mg/L的Pb^(2+)明显地促进了光降解。在天然海水中,1 mg/L的Pb^(2+)对三唑磷的光降解起了抑制作用,而0.01 mg/L和0.1 mg/L的Pb^(2+)在光照前60 min促进了光降解,后60 min则起了抑制作用。不同浓度的Fe^(3+)在人工海水和去离子水中会促进光降解,而在天然海水中则表现为抑制作用。该实验模拟结果可为水环境中该种农药污染的治理提供重要的理论依据。 展开更多
关键词 三唑磷 光化学降解 Pb^(2+) Fe^(3+) 水溶液
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Gene expression,transcription factor binding and histone modification predict leaf adaxial-abaxial polarity related genes
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作者 Wei Sun Zhicheng Zhang +2 位作者 Guusje Bonnema Xiaowu Wang Aalt Dirk Jan van Dijk 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期971-982,共12页
Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we... Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we applied a combination of in silico prediction using machine learning(ML)and experimental analysis.A Random Forest model was trained using genes known to influence ad-abaxial polarity as ground truth.Gene expression data from various tissues and conditions as well as promoter regulation data derived from transcription factor chromatin immunoprecipitation sequencing(ChIP-seq)was used as input,enabling the prediction of novel ad-abaxial polarity-related genes and additional transcription factors.Parallel to this,available and newly-obtained transcriptome data enabled us to identify genes differentially expressed across leaf ad-abaxial sides.Based on these analyses,we obtained a set of 111 novel genes which are involved in leaf ad-abaxial specialization.To explore implications for vegetable crop breeding,we examined the conservation of expression patterns between Arabidopsis and Brassica rapa using single-cell transcriptomics.The results demonstrated the utility of our computational approach for predicting candidate genes in crop species.Our findings expand the understanding of the genetic networks governing leaf ad-abaxial differentiation in agriculturally important vegetables,enhancing comprehension of natural variation impacting leaf morphology and development,with demonstrable breeding applications. 展开更多
关键词 Machine learning Leaf polarity Arabidopsis thaliana Brassica rapa Transcription factor
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Regional economic assessment of a novel place-based model for sustainable food systems
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作者 Susanna Kujala Kari Koppelmäki 《Geography and Sustainability》 CSCD 2024年第2期220-229,共10页
Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroec... Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroecological symbiosis(AES),a novel food system model,is an example of a suggested system-level change to attain sustainability targets;it is a symbiosis of food production and processing using renewable energy that uses its own feedstock.AES has already been found advantageous from the ecological and biophysical viewpoints,but a regional economic evaluation of the model is still lacking.Thus,the aim of our paper is to assess the regional economic impact of a possible systemic change in the food system using the network of agroecological symbiosis(NAES)as an example.We applied scenarios representing different ways of moving towards envisioned NAES models in Mäntsälä,Finland,and a computable general equilibrium model to evaluate the regional economic impact.According to our results,both regional economy and employment would increase,and the regional production base would diversify with NAES implementation applied to the region,but the extent of the benefits varies between scenarios.The scenario that includes change in both public and private food demand,production of bioenergy and utilization of by-products would cause the largest impacts.However,realizing NAES requires investments that may influence the actual implementation of such models.Nonetheless,a change towards NAES can promote an economically and spatially just transition to sustainability,as NAES seems to be economically most beneficial for rural areas. 展开更多
关键词 SUSTAINABILITY Regional economy Localized food system Renewable energy CIRCULARITY
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Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279
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作者 K.Akhila Ranjeev Misra +1 位作者 Savithri H.Ezhikode K.Jeena 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期307-314,共8页
We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–2020.We use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the purpose.The X-ray spectrum can be modeled as a ... We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–2020.We use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the purpose.The X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe Kαline emission,at all epochs.We determined the source’s X-ray flux and luminosity at these different epochs.We find significant variations in the source’s flux state.We also investigate the variations in the source’s spectral components during the observation period.We find that the photon index and hence the spectral shape follow the variations only over longer time periods.We probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters. 展开更多
关键词 galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies
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欧洲食用胶原蛋白肽分析方法简介
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作者 白雅昕 肖彩霞 《明胶科学与技术》 CAS 2024年第1期49-51,共3页
胶原蛋白肽的功能特性引起大家的极大兴趣,其在食品和保健品的应用广泛,所以其质量与消费者的健康密切相关。针对于此,本文中介绍了欧洲明胶制造商(Gelatine Manufacture of Europe,GME)制定的胶原蛋白肽分析方法标准(GME标准),该标准... 胶原蛋白肽的功能特性引起大家的极大兴趣,其在食品和保健品的应用广泛,所以其质量与消费者的健康密切相关。针对于此,本文中介绍了欧洲明胶制造商(Gelatine Manufacture of Europe,GME)制定的胶原蛋白肽分析方法标准(GME标准),该标准涵盖了鉴别、化学质量和微生物质量等多个方面的检测,希望能为胶原蛋白肽质量控制提供参考. 展开更多
关键词 胶原蛋白肽 胶原蛋白 GME标准 检测方法
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胶原蛋白三肽活性的研究进展
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作者 贺天文 《明胶科学与技术》 CAS 2024年第1期13-22,共10页
胶原蛋白广泛存在于自然界中,是动物结缔组织中极其重要的一种结构蛋白。基于胶原蛋白结构的多样性和独特性,也赋予了其水解后的胶原蛋白三肽的某些特殊的生物活性,如抗氧化性、伤口修复、保护骨和关节等。本文简要综述了胶原蛋白三肽... 胶原蛋白广泛存在于自然界中,是动物结缔组织中极其重要的一种结构蛋白。基于胶原蛋白结构的多样性和独特性,也赋予了其水解后的胶原蛋白三肽的某些特殊的生物活性,如抗氧化性、伤口修复、保护骨和关节等。本文简要综述了胶原蛋白三肽的生物活性、吸收和应用,并展望了胶原蛋白三肽的市场前景,为源于胶原蛋白的肽在膳食补充剂、保健品和日用化妆品等领域的应用提供参考。 展开更多
关键词 胶原蛋白 胶原蛋白三肽 生物活性 蛋白质吸收
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Endoscopic treatment of scarred polyps with a non-thermal device(Endorotor):A review of the literature
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作者 Mariam Zaghloul Hameed Rehman +2 位作者 Stefano Sansone Konstantinos Argyriou Adolfo Parra-Blanco 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1706-1713,共8页
Endoscopic resection(ER)of colorectal polyps has become a daily practice in most endoscopic units providing a colorectal cancer screening program and requires the availability of local experts and high-end endoscopic ... Endoscopic resection(ER)of colorectal polyps has become a daily practice in most endoscopic units providing a colorectal cancer screening program and requires the availability of local experts and high-end endoscopic devices.ER procedures have evolved over the past few years from endoscopic mucosal resection(EMR)to more advanced techniques,such as endoscopic submucosal dissection and endo-scopic full-thickness resection.Complete resection and disease eradication are the ultimate goals of ER-based techniques,and novel devices have been developed to achieve these goals.The EndoRotor®Endoscopic Powered Resection System(Interscope Medical,Inc.,Northbridge,Massachusetts,United States)is one such device.The EndoRotor is a powered resection tool for the removal of alimentary tract mucosa,including post-EMR persistent lesions with scarring,and has both CE Mark and FDA clearance.This review covers available published evidence documenting the usefulness of EndoRotor for the management of recurrent colorectal polyps. 展开更多
关键词 EndoRotor Scarred polyps Recurrent polyps Colorectal cancer Colorectal polyps
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Comparative Study of Solar PV Power Plant Dimensionnement Connected to Network Based on Monofacial and Bifacial Modules
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作者 DJOSSOU Ayihaou Armand VODOUNNOU Edmond Claude +5 位作者 FANNOU Jean Louis Comlan DANSOU MidokpêRomuald SEMASSOU Guy Clarence HOUNGAN Comlan Aristide GUIDI Tognon Clotilde Thierno Amadou Barry 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第1期36-44,共9页
This article presents the results of comparative study of two PV solar modules technologies,namely monofacial and bifacial.This study main objective is to identify conditions and parameters that make it possible to ob... This article presents the results of comparative study of two PV solar modules technologies,namely monofacial and bifacial.This study main objective is to identify conditions and parameters that make it possible to obtain better energy and economic efficiency from one or other of two technologies.The study reason lies in revival observed on bifacial module in recent years where all the major manufacturers of PV solar panels are developing them where in a few years,this technology risks being at the same price as the monofacial solar panel with better efficiency.Economic indicator used is energy levelized cost(LCOE)which is function technology type,energy productivity,annual investment and operation cost.To achieve this,a 3.685 MWc solar PV power plant was dimensioned and simulated under Matlab for a 3.5 ha site with a 2,320,740,602 FCFA budget for monofacial installation,against 1,925,188,640 FCFA for 2.73 MWc bifacial installation.The LCOE comparative analysis of two technologies calculated over a period of 25 years,showed that plant with bifacial panels is more beneficial if bifacial gain is greater than 9%.It has further been found that it is possible to gain up to 40%of invested cost if bifacial gain reaches 45%.Finally,a loss of about 10%of invested cost could be recorded if bifacial gain is less than 9%. 展开更多
关键词 Solar PV power plant SIZING Monofacial panels Bifacial panels LCOE.
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卢旺达农业有害生物防控技术的研究与应用现状
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作者 高韩 张利荷 +2 位作者 刘文媚 Marguerite Mukangango 邱宝利 《植物医学》 2024年第3期10-17,共8页
卢旺达是非洲中东部一个以农业为经济支柱的国家,种植的农作物主要包括木薯、番茄、玉米、香蕉、辣椒、相橘与水稻等.农作物在生产过程中易遭受病虫害的持续危害,严重时可导致农民损失惨重,甚至颗粒无收.本文综述了卢旺达主要农作物病... 卢旺达是非洲中东部一个以农业为经济支柱的国家,种植的农作物主要包括木薯、番茄、玉米、香蕉、辣椒、相橘与水稻等.农作物在生产过程中易遭受病虫害的持续危害,严重时可导致农民损失惨重,甚至颗粒无收.本文综述了卢旺达主要农作物病虫害的发生与防控技术研究和应用进展,同时对卢旺达农业可持续发展及有害生物可持续防控对策进行了分析,旨在为卢旺达地区农业病虫害的防控提供参考,以期实现在我国援非政策下卢旺达农业的稳定和可持续性发展. 展开更多
关键词 卢旺达 农业 有害生物 防控技术 研究现状
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2023: Weather and Climate Extremes Hitting the Globe with Emerging Features
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作者 Wenxia ZHANG Robin CLARK +12 位作者 Tianjun ZHOU Laurent LI Chao LI Juan RIVERA Lixia ZHANG Kexin GUI Tingyu ZHANG Lan LI Rongyun PAN Yongjun CHEN Shijie TANG Xin HUANG Shuai HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1001-1016,共16页
Globally,2023 was the warmest observed year on record since at least 1850 and,according to proxy evidence,possibly of the past 100000 years.As in recent years,the record warmth has again been accompanied with yet more... Globally,2023 was the warmest observed year on record since at least 1850 and,according to proxy evidence,possibly of the past 100000 years.As in recent years,the record warmth has again been accompanied with yet more extreme weather and climate events throughout the world.Here,we provide an overview of those of 2023,with details and key background causes to help build upon our understanding of the roles of internal climate variability and anthropogenic climate change.We also highlight emerging features associated with some of these extreme events.Hot extremes are occurring earlier in the year,and increasingly simultaneously in differing parts of the world(e.g.,the concurrent hot extremes in the Northern Hemisphere in July 2023).Intense cyclones are exacerbating precipitation extremes(e.g.,the North China flooding in July and the Libya flooding in September).Droughts in some regions(e.g.,California and the Horn of Africa)have transitioned into flood conditions.Climate extremes also show increasing interactions with ecosystems via wildfires(e.g.,those in Hawaii in August and in Canada from spring to autumn 2023)and sandstorms(e.g.,those in Mongolia in April 2023).Finally,we also consider the challenges to research that these emerging characteristics present for the strategy and practice of adaptation. 展开更多
关键词 weather and climate extremes temperature extremes extreme precipitation DROUGHT WILDFIRES
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Overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with Obstacles Using Lattice Boltzmann Method
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作者 Siham Hammid Khatir Naima +7 位作者 Omolayo M.Ikumapayi Cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer Ali Hussien Younes Menni 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期273-299,共27页
The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstac... The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower walls.The research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding environment.Temperature jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle boundaries.The study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and 0.05.The outcomes indicate that rarefaction has a significant impact on the velocity and temperature distribution.The presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the outlet.In MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the MC.The findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications. 展开更多
关键词 MICROFLUID rarefied flow LBM MICROCHANNEL Knudsen number numerical simulation
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Thermo-Mechanical, Physico-Chemical, Morphological, and Fire Characteristics of Eco-Friendly Particleboard Manufactured with Phosphorylated Lignin Addition
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作者 Apri Heri Iswanto Harisyah Manurung +14 位作者 Asma Sohail Lee Seng Hua Petar Antov Deded Sarip Nawawi Sarah Latifah Dewi Shafa Kayla Sukma Surya Kusumah Muhammad Adly Rahandi Lubis Linda MakovickáOsvaldová MohdHazwan Hussin Rangabhashiyam Selvasembian Lum Wei Chen Puji Rahmawati Nurcahyani Nam Hun Kim Widya Fatriasari 《Journal of Renewable Materials》 EI CAS 2024年第7期1311-1341,共31页
Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics ... Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics of particleboards were compared to that of ultralow emitting formaldehyde(ULEF-UF).Thefillers derived from Eucalyptus spp.kraft-lignin were added forflame retardancy enhancement.10%of each lignin and modified lig-nin was added into the ULEF-UF and citric acid-sucrose bonded particleboards.Analyses applied to particle-boards included thermal characteristics,X-ray diffraction analysis(XRD),morphological properties,Fourier transform infrared spectroscopy(FTIR),as well as physical,mechanical,andfire resistance characteristics of the laboratory-fabricated particleboards.Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acid-sucrose was not significant.The introduction offiller exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose.Generally,the presence of lignin,lignosulfonate,and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards,although their dimensional stability has deteriorated.Markedly,the use of lignin and lignosulfonate enhanced thefire resis-tance of the particleboards produced with lower observed weight loss.All laboratory particleboards exhibited satisfactoryfire resistance,attaining a V-0 rating in according to the UL-94 standard. 展开更多
关键词 Modified lignin eco-friendly particleboard fire and thermal properties citric acid-sucrose ultralow-emitting urea-formaldehyde resin
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组合捕收剂协同浮选-高梯度磁选处理中非某氧化铜钴矿试验研究 被引量:2
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作者 陈代雄 沈楼燕 +3 位作者 肖骏 余浔 胡波 李晓东 《湖南有色金属》 CAS 2023年第3期15-19,共5页
为了解决中非共和国某大型氧化铜钴矿常规选矿工艺选矿回收率低、经济效益差等突出问题,文章创新性地引入浮-磁联合工艺处理该矿区产出的代表性矿石,通过大量试验研究,筛选出苯甲羟肟酸+戊基黄药在2∶1的配比下的组合捕收剂为最佳的浮... 为了解决中非共和国某大型氧化铜钴矿常规选矿工艺选矿回收率低、经济效益差等突出问题,文章创新性地引入浮-磁联合工艺处理该矿区产出的代表性矿石,通过大量试验研究,筛选出苯甲羟肟酸+戊基黄药在2∶1的配比下的组合捕收剂为最佳的浮选捕收剂,大幅度地提高了氧化铜钴矿的浮选回收率,针对浮选尾矿中部分铜钴矿物以铜锰钴硅氧化结合物态赋存的特性,开发高梯度磁选机用于处理浮选尾矿,得到一个以铜、钴为主的磁选精矿,浮-磁联合工艺产出的浮选铜钴精矿、磁选铜钴精矿中总铜回收率达到了8866%,总钴回收率达到了6892%,实现了对中非氧化铜钴矿中铜钴资源的高效综合回收。 展开更多
关键词 氧化铜钴矿 浮选 组合捕收剂 回收率 磁选
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广州某地下水污染场地监控自然衰减修复模拟 被引量:3
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作者 袁昊辰 张幼宽 梁修雨 《地质科技通报》 CAS CSCD 北大核心 2023年第4期268-278,共11页
监控自然衰减(MNA)作为一种成本低、不产生二次污染物、对污染场地环境影响较小的地下水污染修复方法,具有较高的应用价值和发展前景,值得实践与研究。选取广州某地下水污染场地作为研究区,评价MNA修复方法的适用性。基于水文地质条件... 监控自然衰减(MNA)作为一种成本低、不产生二次污染物、对污染场地环境影响较小的地下水污染修复方法,具有较高的应用价值和发展前景,值得实践与研究。选取广州某地下水污染场地作为研究区,评价MNA修复方法的适用性。基于水文地质条件及污染现状分析,运用地下水数值模拟程序MODFLOW建立了污染场地地下水流模型,运用污染物迁移数值模拟程序MT3DMS建立了场地污染物迁移模型,分别模拟了场地地下水流、主要污染物总石油烃(TPH)和重金属镍(Ni)的迁移过程。基于模型,对比监控自然衰减和抽出处理与监控自然衰减结合的2种方案修复效果。结果表明,TPH和Ni对于Freundlich常数及Freundlich指数变化均较为敏感;TPH的自然衰减效果较好,采用自然衰减方案,经过850 d可由初始浓度1.52 mg/L衰减到修复目标值(0.3 mg/L);Ni衰减较慢,适宜采用结合抽出处理的监控下自然衰减方案,经过300 d可由初始浓度0.13 mg/L达到修复目标值(0.02 mg/L)。在自然衰减能力较强或地下水流速较缓的条件下,适宜采用监控自然衰减修复方案;在自然衰减能力较弱或地下水有显著流动的情况下,适宜采用结合抽出处理的监控自然衰减修复方案。研究结果对地下水污染修复具有参考价值与借鉴意义。 展开更多
关键词 监控自然衰减 地下水污染修复 数值模拟 抽出处理
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联合接种原生动物和木霉对黄瓜生长及土壤微生物区系的影响
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作者 莫雅旎 郭赛 +6 位作者 欧燕楠 焦子轩 黄若菱 李荣 沈宗专 Geisen Stefan 沈其荣 《南京农业大学学报》 CAS CSCD 北大核心 2023年第2期297-305,共9页
[目的]本文旨在探究吞噬性原生动物、真菌及两者联合对黄瓜生长和土壤微生物群落组成的影响。[方法]供试黄瓜品种为‘露丰黄瓜’,采用盆栽试验,设计不接种对照(CK)、单独接种贵州木霉(Trichoderma guizhouense NJAU 4742)(T处理)、单独... [目的]本文旨在探究吞噬性原生动物、真菌及两者联合对黄瓜生长和土壤微生物群落组成的影响。[方法]供试黄瓜品种为‘露丰黄瓜’,采用盆栽试验,设计不接种对照(CK)、单独接种贵州木霉(Trichoderma guizhouense NJAU 4742)(T处理)、单独接种丝竹虫(Cercomomnas lenta)(C处理)、组合接种丝竹虫和贵州木霉(T+C处理)4个处理,处理2周后采集植株及土壤样品,评估各处理对黄瓜性状及土壤细菌和真菌群落的影响。[结果]相较于CK,T、C和T+C 3个处理黄瓜株高分别增加6.0%、12.5%和21.5%,生物量分别提高5.6%、12.9%和24.0%,即贵州木霉和丝竹虫均能促进黄瓜生长且两者组合能够进一步增强促生效应。基于主坐标分析发现,3个处理均显著改变了土壤细菌和真菌群落组成,随机森林模型进一步发现细菌和真菌群落组成是影响黄瓜生物量的主要因素。线性判别分析发现,与CK相比,3个处理分别激发22、51和82个关键细菌操作分类单元(OTU),2、6和16个关键真菌OTU;T+C处理激发了更多的与黄瓜促生相关的OTU,其中,有21个关键细菌OTU仅在T+C处理中被激发,对黄瓜促生贡献最大的分别归属于Parasediminibacterium、Fluviicola和Roseimaritima;有11个关键真菌OTU仅在T+C处理中被激发,对黄瓜促生贡献最大的分别归属于隔指孢属、Melanoleuca和毛壳菌属。[结论]相比于单一接种,丝竹虫和木霉组合接种后能更显著促进黄瓜生长,两者协同调控土著细菌和真菌群落,激发并富集潜在的土著功能微生物以塑造更有利于黄瓜生长的土壤微生物群落。 展开更多
关键词 黄瓜 原生动物 木霉 接种 土壤微生物群落 促生
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HadISDH.extremes Part Ⅰ:A Gridded Wet Bulb Temperature Extremes Index Product for Climate Monitoring 被引量:2
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作者 Kate M.WILLETT 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期1952-1967,共16页
HadISDH.extremes is an annually updated global gridded monthly monitoring product of wet and dry bulb temperature–based extremes indices,from January 1973 to December 2022.Data quality,including spatial and temporal ... HadISDH.extremes is an annually updated global gridded monthly monitoring product of wet and dry bulb temperature–based extremes indices,from January 1973 to December 2022.Data quality,including spatial and temporal stability,is a key focus.The hourly data are quality controlled.Homogeneity is assessed on monthly means and used to score each gridbox according to its homogeneity rather than to apply adjustments.This enables user-specific screening for temporal stability and avoids errors from inferring adjustments from monthly means for the daily maximum values.For general use,a score(HQ Flag)of 0 to 6 is recommended.A range of indices are presented,aligning with existing standardised indices.Uniquely,provision of both wet and dry bulb indices allows exploration of heat event character—whether it is a“humid and hot”,“dry and hot”or“humid and warm”event.It is designed for analysis of long-term trends in regional features.HadISDH.extremes can be used to study local events,but given the greater vulnerability to errors of maximum compared to mean values,cross-validation with independent information is advised. 展开更多
关键词 wet bulb temperature heat extremes climate monitoring
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HadISDH.extremes Part Ⅱ:Exploring Humid Heat Extremes Using Wet Bulb Temperature Indices 被引量:2
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作者 Kate M.WILLETT 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期1968-1985,共18页
Heat events may be humid or dry.While several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity characteristics.The new HadISDH.extrem... Heat events may be humid or dry.While several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity characteristics.The new HadISDH.extremes global gridded monitoring product uniquely provides a range of wet and dry bulb temperature extremes indices.Analysis of this new data product demonstrates its value as a tool for quantifying exposure to humid verses dry heat events.It also enables exploration into“stealth heat events”,where humidity is high,perhaps enough to affect productivity and health,while temperature remains moderate.Such events may not typically be identified as“heat events”by temperature-focused heat indices.Over 1973-2022,the peak magnitude of humid extremes(maximum daily wet bulb temperature over a month;T_(w)X)for the global annual mean increased significantly at 0.13±0.04℃(10 yr)^(−1),which is slightly slower than the global annual mean T_(w) increase of 0.22±0.04℃(10 yr)^(−1).The frequency of moderate humid extreme events per year(90th per-centile daily maxima wet bulb temperature exceedance;T_(w)X90p)also increased significantly at 4.61±1.07 d yr^(−1)(10 yr)^(−1).These rates were slower than for temperature extremes,TX and TX90p,which respectively increased significantly at 0.27±0.04℃(10 yr)^(−1) and 5.53±0.72 d yr^(−1)(10 yr)^(−1).Similarly,for the UK/Europe focus region,JJA-mean T_(w)X increased significantly,again at a slower rate than for TX and mean T_(w).HadISDH.extremes shows some evidence of“stealth heat events”occurring where humidity is high but temperature remains more moderate. 展开更多
关键词 wet bulb temperature heat extremes climate monitoring
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