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Depth profiling of arsenian pyrite in Carlin-type ores through wet chemistry

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Acta Geochimica 2023年第2期42卷 256-265页

作者： Meizhi Yang Quan Wan Xin Nie Suxing luo Yuhong Fu Ping Zeng wenqi luo State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Comparative Planetology Hefei 230026China Department of Chemistry and Chemical Engineering Zunyi Normal CollegeZunyi 563006China School of Geographic and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China

Enrichment of As and Au at the overgrowth rims of arsenian pyrite is a distinctive feature of Carlin-type gold ores.Revealing distribution of such key elements in high resolution is of fundamental importance yet often proves challenging.In this study,repeated non-oxidative acid etching of ore samples from Shuiyindong gold deposit was applied to enable elemental depth profiling of goldbearing arsenian pyrite grains.ICP-OES and AAS were used to determine the dissolved Fe,As,and Au concentrations in each of the etching solutions,and XPS was carried out to exam the etched mineral surfaces.In contrast to conventional ion beam etching that may cause substantial sample damage,our acid etching method does not seem to significantly alter the composition and chemical state of the samples.The etched depths directly converted from the measured elemental concentrations can reproducibly reach a very high resolution of~1 nm,and can be conveniently controlled through varying the etching time.While the Fe and As depth profiles consistently reflect the surface oxidation property of arsenian pyrite,the Au profile displaying an obvious upward trend reveals the ore fluid evolution at the late stage of mineralization.Based on our experimental results,we demonstrate that our wet chemistry method is capable of effective depth profiling of gold ore and perhaps other geological samples,with advantages surpassing many instrumental techniques including negligible sample damage,nanoscale resolution as well as isotropic etching.

关键词： Wet chemistry Acid etching Depth profiling Carlin-type gold deposits Arsenian pyrite

Toward to agricultural green development by multi-objective zoning and nitrogen nutrient management:a case study in the Baiyangdian Basin,China

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 140-154页

作者： Xiaomeng ZHANG Xiangwen FAN wenqi MA Zhaohai BAI Jiafa luo Jing YANG Ling LIU Jianjie ZHANG Lin MA College of Resources and Environmental Sciences Hebei Agricultural UniversityBaoding 071000China Center for Agricultural Resources Research Institute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Ruakura Research Centre AgResearch LimitedHamilton 3240New Zealand

Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Optimized management of crop–livestock systems is the key measure to realize agricultural green transformation.However,optimized management of crop–livestock systems that use multi-objective zoning is lacking.This study employed a multi-objective zoning management approach to comprehensively analyze four indicators:ammonia volatilization,nitrogen surplus,soil carrying capacity and ecological red line area.With its significant ecological integrity and a strong emphasis on sustainability,the Baiyangdian Basin serves as a unique and suitable test case for conducting analyses on multi-objective nutrient optimization management,with the aim to facilitate the agricultural green transformation.This study finds that less than 8%of the area in the Baiyangdian Basin meet the acceptable environmental indicator standard,whereas around 50%of the area that had both nitrogen surplus and ammonia volatilization exceeded the threshold.Implementation of unified management,that is,the same management technique across the study areas,could result in an increase of areas meeting environmental indicator thresholds to 21.1%.This project developed a novel multi-indicator partition optimization method,in which distinct measures are tailored for different areas to satisfy multiple environmental indicators.Implementation of this method,could potentially bring more than 50%area below the threshold,and areas with ammonia emissions and nitrogen surplus could be reduced to 15.8%.The multi-indicators partition optimization method represents a more advanced and efficiency-oriented management approach when compared to unified management.This approach could be regarded as the best available option to help China achieve agricultural transformation to improve efficient production and reduce environmental pollution.It is recommended that cu

关键词： Agricultural green development Baiyangdian Basin environmental emission threshold partition management

Global latitudinal patterns in leaf herbivory are related to variation in climate, rather than phytochemicals or mycorrhizal types

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National Science Review 2023年第12期10卷 66-69页

作者： Hui Tang Xianhui Zhu Yonglin Zhong Yuanzhi Li wenqi luo Hanlun Liu Patrice Descombes Alan C.Gange Chengjin Chu State Key Laboratory of Biocontrol School of Ecology/School of Life Sciences Sun Yat-sen University Guangdong Provincial Key Laboratory of Silviculture Protection and Utilization Guangdong Academy of Forestry Musée et Jardins botaniques cantonaux Department of Ecology and Evolution University of Lausanne Department of Biological Sciences Royal Holloway University of London

Plant-herbivore interactions are among the most important factors shaping plant community dynamics and ecosystem functioning. The latitudinal herbivory hypothesis proposed that insect herbivory rates decline with increasing latitudes owing to benign environmental conditions in the tropics, but studies have produced contradictory conclusions[1–3].

关键词： IMPACTS

Global multifaceted biodiversity patterns,centers,and conservation needs in angiosperms

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Science China(Life Sciences) 2024年第4期67卷 817-828页

作者： Ao luo Yaoqi Li Nawal Shrestha Xiaoting Xu Xiangyan Su Yichao Li Tong Lyu Kilara Waris Zhiyao Tang Xiaojuan Liu Luxiang Lin Yongsheng Chen Kuiling Zu wenqi Song Shijia Peng Niklaus E.Zimmermann Loïc Pellissier Zhiheng Wang Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Health and Environmental Sciences Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China Land Consolidation and Rehabilitation Center Ministry of Natural ResourcesBeijing 100035China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesKunming 650201China Swiss Federal Research Institute WSL Birmensdorf 8903Switzerland Department of Environmental Systems Science ETH ZürichZürich 8092Switzerland

The Convention on Biological Diversity seeks to conserve at least 30%of global land and water areas by 2030,which is a challenge but also an opportunity to better preserve biodiversity,including flowering plants(angiosperms).Herein,we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 species.Using this database,we constructed biodiversity-environment models to predict global patterns of taxonomic,phylogenetic,and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity facets.We further evaluated the current protection status of the biodiversity centers of these diversity facets.Our results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation priorities.Idiosyncratic centers of functional diversity,particularly of herbaceous species,were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic facets.Our global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms(woody vs.herbaceous),thus providing directions for guiding the future conservation of global plant diversity.

关键词： angiosperms species richness phylogenetic diversity functional diversity plant traits woody species herbaceous species

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氮掺杂多孔污泥炭活化过二硫酸盐降解橙黄Ⅱ

工业水处理 2024年第3期44卷 133-141页

作者：李文奇罗才贵熊瑜婷罗仙平矿冶环境污染防控江西省重点实验室江西赣州341000 钨资源高效开发及应用教育部工程研究中心江西赣州341000

以市政污泥为碳源、碳酸氢钾为活化剂、尿素为氮源,制备了氮掺杂多孔污泥生物炭(NKBC),并采用N2吸附-脱附实验、SEM、XRD、XPS对其比表面积、表面特征进行了系列表征与分析,结果表明,NKBC具有较大的比表面积,由于N负载于NKBC孔道内,其... 详细信息

以市政污泥为碳源、碳酸氢钾为活化剂、尿素为氮源,制备了氮掺杂多孔污泥生物炭(NKBC),并采用N2吸附-脱附实验、SEM、XRD、XPS对其比表面积、表面特征进行了系列表征与分析,结果表明,NKBC具有较大的比表面积,由于N负载于NKBC孔道内,其表面褶皱、缺陷较多,活化位点较多。将NKBC用于活化过二硫酸盐(PDS)降解橙黄Ⅱ,考察NKBC/PDS体系降解橙黄Ⅱ的性能,结果表明,在加入PDS 20 min后,NKBC/PDS体系对橙黄Ⅱ的降解率高达99.7%;该体系可在较宽pH范围(3~11)及常见阴离子存在条件下发挥作用。自由基猝灭实验和EPR光谱结果表明,NKBC/PDS体系降解橙黄Ⅱ的主要活性物种有·OH、SO_(4)^(·-)和^(1)O_(2),且以^(1)O_(2)为主。该研究所构建的NKBC/PDS体系可应用于染料废水的处理,实现“以废治废”的目标。

关键词：氮掺杂污泥生物炭过二硫酸盐橙黄Ⅱ

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船舶疏水系统流量压力脉动特性研究

机床与液压 2024年第6期52卷 103-109页

作者：刘裕燊罗小辉常文奇华中科技大学机械科学与工程学院湖北武汉430074

疏水系统在船舶中担任疏干排污等重要工作,其工作时产生的管道流量及压力脉动是系统产生振动噪声的主要原因。降低系统流量压力脉动、抑制系统噪声的关键之一是掌握系统流量压力脉动特性。通过分析低噪声柱塞泵的结构原理,结合疏水系统... 详细信息

疏水系统在船舶中担任疏干排污等重要工作,其工作时产生的管道流量及压力脉动是系统产生振动噪声的主要原因。降低系统流量压力脉动、抑制系统噪声的关键之一是掌握系统流量压力脉动特性。通过分析低噪声柱塞泵的结构原理,结合疏水系统管道结构,建立完整的疏水系统仿真模型;通过试验台对仿真模型的准确性进行验证;最后基于仿真模型,对疏水系统特性及压力脉动的影响因素进行研究。结果表明:流量压力脉动主要作用频率为5 Hz和20 Hz;阀开度及管道长度对压力脉动影响较大,泵参数变化的影响较小,后续设计优化应优先考虑出口管道。

关键词：疏水系统柱塞泵流量脉动压力脉动

从功能性状的种内变异和环境因子的角度理解局域森林群落嵌套格局的成因

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Journal of Plant Ecology 2022年第6期15卷 1185-1198页

作者： Weitao Wang Yun Jiang Yongfa Chen wenqi luo Dong He Youshi Wang Chengjin Chu Buhang Li State Key Laboratory of Biocontrol School of Life Sciences/School of EcologySun Yat-sen UniversityGuangzhou 510275China Zhuhai Branch of State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University at ZhuhaiZhuhai 519087China College of Resources and Environment Science Xinjiang UniversityUrumqi 830046China

生态学中“嵌套”的概念源于生物地理学,指的是物种较少的斑块为物种较多斑块的嵌套子集,在集合群落和生物互作网络中得到了广泛应用,嵌套格局的存在往往被认为有利于物种多样性的维持和保证了网络结构的稳定性。目前,针对局域植物群落... 详细信息

生态学中“嵌套”的概念源于生物地理学,指的是物种较少的斑块为物种较多斑块的嵌套子集,在集合群落和生物互作网络中得到了广泛应用,嵌套格局的存在往往被认为有利于物种多样性的维持和保证了网络结构的稳定性。目前,针对局域植物群落嵌套格局的研究较少,相关研究也很少将功能性状和环境因子同时纳入考虑以探讨格局成因。本研究依托位于中国南部的黑石顶50公顷森林大样地,将样地植物普查数据和位置信息转换为物种-样方矩阵,对该矩阵重排寻找到矩阵的最大嵌套结构。针对最大嵌套结构,使用零模型方法验证嵌套结构的显著性;根据物种和样方在最大嵌套结构内的排序,划定物种和样方的嵌套等级。随后,使用回归树方法分别确定物种和样方嵌套等级与功能性状和环境因子的联系,物种功能性状数据包括性状均值与性状种内变异。研究结果表明,黑石顶植物群落存在显著的嵌套格局,回归树结果发现,样方嵌套等级与土壤速效磷、土壤水分含量、土壤有机质含量和土壤pH相关,以上因子共解释了32%的样方嵌套等级变异;物种嵌套等级主要受物种功能性状的种内变异而非性状均值影响,其中叶片碳含量、叶片pH、叶片干物质含量和最大光合速率的种内变异是主导因素,它们共解释了物种嵌套等级变异的49%。以上结果说明,关键性的环境因子与物种对环境的适应能力共同作用,使局域植物群落形成了嵌套格局。本研究从样方嵌套等级和物种嵌套等级的角度探讨嵌套格局成因,为理解嵌套格局提供了新的角度,加深了研究者对于局域植物群落构建机制的理解。

关键词：环境因子功能性状嵌套空间格局亚热带森林

絮凝沉淀与生物曝气滤池结合处理杨木心材生物化学机械法制浆废水

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中国造纸学报 2024年第1期39卷 38-46页

作者：牛虎军谢益民罗文琪周安乡薛超湖北工业大学制浆造纸研究院湖北武汉430068 湖北工业大学绿色轻工材料湖北省重点实验室湖北武汉430068 湖北华海纤维科技股份有限公司湖北南漳441500

本研究利用白腐菌Trametes sp.48424预处理杨木心材,结合絮凝沉淀与生物曝气滤池(BAF),处理化学机械法制浆过程中产生的综合废水,研究废水回用对生物化学机械法制浆及BAF的影响,探究处理后废水回用的可行性。结果表明,采用白腐菌预处理... 详细信息

本研究利用白腐菌Trametes sp.48424预处理杨木心材,结合絮凝沉淀与生物曝气滤池(BAF),处理化学机械法制浆过程中产生的综合废水,研究废水回用对生物化学机械法制浆及BAF的影响,探究处理后废水回用的可行性。结果表明,采用白腐菌预处理技术,能够抵消添加2%(相对于原料绝干质量)的NaOH所产生的CODCr。絮凝沉淀处理后,CODCr的最高去除率为49.9%。BAF处理后COD_(Cr)最高去除率可达91.8%,出水CODCr浓度降至39.8 mg/L,达到制浆废水回用和排放的标准。废水回用会降低BAF的整体效率,且处理后的废水回用于制浆系统,对浆料的成纸性能也会产生一定的影响;回用1次后出水CODCr浓度升至76.3 mg/L,故处理后的废水只能回用1次。

关键词：白腐菌生物化学机械浆絮凝沉淀法生物曝气滤池废水回用

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A Perspective on the Evolution of Atmospheric Blocking Theories:From Eddy-Mean flow Interaction to Nonlinear Multiscale Interaction

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Advances in Atmospheric Sciences 2023年第4期40卷 553-569页

作者： Dehai luo Binhe luo wenqi ZHANG Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China University of Chinese Academy of Sciences Beijing 101499China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100091China Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China

In this paper,we first review the research advancements in blocking dynamics and highlight the merits and drawbacks of the previous theories of atmospheric blocking.Then,the dynamical mechanisms of atmospheric blocking are presented based on a nonlinear multi-scale interaction(NMI)model.Previous studies suggested that the eddy deformation(e.g.,eddy straining,wave breaking,and eddy merging)might lead to the formation and maintenance of atmospheric blocking.However,the results were speculative and problematic because the previous studies,based on the time-mean eddy-mean flow interaction model,cannot identify the causal relationship between the evolution of atmospheric blocking and the eddy deformation.Based on the NMI model,we indicate that the onset,growth,maintenance,and decay of atmospheric blocking is mainly produced by the spatiotemporal evolution of pre-existing upstream synoptic-scale eddies,whereas the eddy deformation is a concomitant phenomenon of the blocking formation.The lifetime of blocking is mainly determined by the meridional background potential vorticity gradient(PVy)because a small PVyfavors weak energy dispersion and strong nonlinearity to sustain the blocking.But the zonal movement of atmospheric blocking is associated with the background westerly wind,PVy,and the blocking amplitude.Using this NMI model,a bridge from the climate change to sub-seasonal atmospheric blocking and weather extremes might be established via examining the effect of climate change on PVy.Thus,it is expected that using the NMI model to explore the dynamics of atmospheric blocking and its change is a new direction in the future.

关键词： atmospheric blocking teleconnection patterns eddy deformation potential vorticity gradient climate change nonlinear multiscale interaction