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栾川矿集区钼矿尾渣与土壤中钼的迁移转化机理

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现代地质 2024年第3期38卷 755-763页

作者：潘飞飞谌宏伟陈丹利赵膂李正最陈辉彭向训刘京河南省地质矿产勘查开发局第三地质勘查院河南郑州450014 河南省金属矿产深孔钻探工程技术研究中心河南郑州450014 长沙理工大学水利与环境工程学院湖南长沙410114 湖南省水务规划设计院有限公司湖南长沙410005 湖南省水文水资源勘测中心湖南长沙410005

为提供栾川矿集区所在流域下游水源地陆浑水库Mo污染的源头控制依据,开展了6座钼矿尾矿库尾渣和土壤的野外调查及三道庄尾矿库尾渣和土壤的Mo赋存形态分析和降雨淋滤试验,以探讨Mo在钼矿尾渣与土壤中的迁移转化机理。结果显示,尾矿库尾... 详细信息

为提供栾川矿集区所在流域下游水源地陆浑水库Mo污染的源头控制依据,开展了6座钼矿尾矿库尾渣和土壤的野外调查及三道庄尾矿库尾渣和土壤的Mo赋存形态分析和降雨淋滤试验,以探讨Mo在钼矿尾渣与土壤中的迁移转化机理。结果显示,尾矿库尾渣Mo平均含量为238.24 mg/kg,浸出液Mo含量达0.26 mg/l;土壤Mo平均含量为125.88 mg/kg;尾渣残渣态Mo占比97.71%,土壤残渣态Mo占比63.66%,可交换态和碳酸盐结合态分别占比22.35%和11.80%。酸-偏碱性降雨淋滤后,尾渣中残渣态Mo占比不同程度减少,中-偏碱性降雨更利于尾渣残渣态Mo向碳酸盐结合态转化,使之由淋滤前的1.19%分别增加到18.85%和24.14%,提高了尾渣中Mo的迁移性。酸性降雨时土壤铁锰氧化态和有机态Mo占比大幅度升高,其他形态Mo占比均一定幅度降低;中性-偏碱性降雨时土壤残渣态和有机态Mo占比升高,碳酸盐结合态和铁锰氧化态大幅度降低,表示酸性降雨可促进土壤中形成铁锰等钼酸盐,而中-偏碱性降雨可能有利于土壤中形成铁锰等氢氧化物和碳酸盐,阻碍了铁锰等钼酸盐的产生,一定程度上提高了Mo的迁移性。因尾渣和土壤矿物组成和理化性质不同,降雨淋滤下Mo在两者中的迁移转化机理存在一定差异,但总体而言,酸-偏碱性降雨均可促进Mo的迁移转化,从而影响水土环境。

关键词：钼矿尾渣土壤 Mo 降雨淋滤赋存形态栾川矿集区

长江漫滩区深基坑开挖诱发地层变形及围护结构响应特性分析

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结构工程师 2024年第3期40卷 165-171页

作者：秦会来田潇屹王蓉王龙吕玺琳中国建筑第二工程局有限公司北京100032 华北电力大学经济与管理学院北京102206 上海勘察设计研究院(集团)股份有限公司上海200093 同济大学岩土及地下工程教育部重点实验室上海200092 同济大学地下建筑与工程系上海200092

针对长江漫滩区典型二元沉积结构地层,以南京某20.6 m深的基坑工程为背景,通过现场实测数据分析及三维有限元数值模拟,探讨了深基坑开挖导致的地层变形和围护结构响应特性。结果表明:地下连续墙水平变形呈“弓”形分布,最大变形位于坑... 详细信息

针对长江漫滩区典型二元沉积结构地层,以南京某20.6 m深的基坑工程为背景,通过现场实测数据分析及三维有限元数值模拟,探讨了深基坑开挖导致的地层变形和围护结构响应特性。结果表明:地下连续墙水平变形呈“弓”形分布,最大变形位于坑底略上方的位置。在0~0.35倍边长和0.65~1倍边长范围,围护结构水平变形随深度大致呈线性变化趋势,距离边角越近围护结构变形越小。地表沉降随时间总体上呈慢-快-慢的变化趋势,立柱桩隆起变形中心位置总体上大于边部及角部位置。

关键词：漫滩区深基坑变形监测数值模拟

饵料种类及培育密度对毛蚶幼虫生长发育的影响

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渔业研究 2024年第4期46卷 360-366页

作者：郝咏芳吕晓民曹琛高超营口市农业农村综合发展服务中心辽宁营口115000 辽宁省海洋水产科学研究院辽宁大连116023 葫芦岛市自然资源事务服务中心辽宁葫芦岛125000

【目的】研究饵料种类及培育密度对毛蚶(Scapharca subcrenata)幼虫生长发育及存活变态的影响。【方法】分别采用单因素方差分析、多重比较分析等方法开展试验研究及数据分析。在水温24.2~27.5℃、盐度26~27、pH 8.2~8.5的条件下,饵料... 详细信息

【目的】研究饵料种类及培育密度对毛蚶(Scapharca subcrenata)幼虫生长发育及存活变态的影响。【方法】分别采用单因素方差分析、多重比较分析等方法开展试验研究及数据分析。在水温24.2~27.5℃、盐度26~27、pH 8.2~8.5的条件下,饵料种类试验设定6个试验组(湛江叉鞭金藻、牟氏角毛藻、小球藻、湛江叉鞭金藻+牟氏角毛藻、牟氏角毛藻+小球藻、湛江叉鞭金藻+牟氏角毛藻+小球藻),设定5个梯度(2、5、10、15、20个/ml)培育密度进行培育试验。【结果】采用单一饵料投喂时,牟氏角毛藻组的幼虫发育效果最好,小球藻组最差;采用混合饵料投喂时,毛蚶幼虫的生长发育及存活率、变态率整体上优于单一饵料,尤其是在牟氏角毛藻+湛江叉鞭金藻+小球藻的混合投喂下,毛蚶幼虫生长发育最快、存活率和变态率最高;在5个试验培育密度梯度范围内,毛蚶幼虫的生长速度、存活率、变态率随着培育密度的增大而降低,发育时间随培育密度的增大呈现延长趋势,但在匍匐期,5个/ml密度组与10个/ml密度组之间的差异不大。【结论】建议在北方地区毛蚶的常温人工育苗过程中,小球藻不可作为主要饵料进行独立使用,需要搭配使用其他藻类,单一饵料投喂时首选牟氏角毛藻,在条件允许的情况下最好选用含有牟氏角毛藻的几种单胞藻的搭配组合;育苗期间,毛蚶幼虫浮游期培育密度为10个/ml左右,匍匐期培育密度以5~10个/ml为宜。【意义】本试验研究为北方地区毛蚶的常温育苗提供有力的数据支撑,具有重要的指导意义,将有效推进毛蚶增养殖产业的发展。

关键词：毛蚶幼虫饵料种类培育密度生长发育

Generalized design of tunable 3D polarized optical multi-focal spots array

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Optoelectronics letters 2022年第12期18卷 705-711页

作者： SHI Changkun XIA Zebin lüPeng ZHANG Zengqi XU Zongwei State Key laboratory of Precision Measuring Technology&Instruments Tianjin UniversityTianjin300072China

We report a generally designed optical modulation method to garner the tunable three-dimensional(3D) polarized optical multi-focal spots arrays in the focusing system of high numerical aperture(NA) objective lens, and it has good compatibility with vector beams of different polarization states. Based on the vector angular spectrum theory and Fourier transform, the vector light fields of Gaussian beam, Bessel-Gaussian(BG) beam and laguerre-Gaussian(lG) beam are modulated with the generally designed multi-focal spots phase filter(MSPF). Meanwhile, a generally designed sidelobe suppression transmission(SST) function is employed to reduce the interference effect of the adjacent focal spots in the arrays. Thus, the one-dimensional(1D) axial multi-focal spots array and the 3D multi-focal spots arrays with high spatial resolution can be generated. The MSPF is flexible and reliable in modulating various vector beams, and exhibiting high tunability for the number(3, 12, 21), spacing(4λ—11.3λ) and spatial distribution(1D—3D) of focal spots in the array. With the generally designed MSPF, the generation of multi-focus array is promoted to be more universal and flexible and shows potential application prospects in femtosecond laser multi-beam parallel processing, particle capture, as well as high-density data storage.

关键词： tunable optical polarization

Context-dependent integrated stress resistance promotes a global invasive pest

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Insect Science 2022年第6期29卷 1790-1804页

作者： Vimbai l.Tarusikirwa Ross N.Cuthbert Reyard Mutamiswa Casper Nyamukondiwa Department of Biological Sciences and Biotechnology Botswana International University of Science and TechnologyPalapyeBotswana GEOMAR Helmholtz-Zentrum fur Ozeanforschung Kiel KielGermany School of Biological Sciences Queen's University BelfastNorth ern IrelandUnited Kingdom Department of Zoology and Entomology University of the Free StateBloemfonteinSouth Africa Tugwi-Mukosi Multidisciplinary Research Institute Midlands State UniversityGweruZimbabwe Department of Zoology and Entomology.Rhodes University MakhandaSouth Africa

In nature,insects concurrently face multiple environmental stressors,a sce-nario likely increasing with climate *** stress resistance(ISR)thus often improves fitness and could drive invasiveness,but how physiological mechanisms influ-ence invasion has lacked ***,we investigated cross-tolerance to abiotic stress factors which may influence range limits in the South American tomato pinworm a global invader that is an ecologically and socially damaging crop ***,we tested the effects of prior rapid cold-and heat-hardening(RCH and RHH),fasting,and desiccation on cold and heat tolerance traits,as well as starvation and desiccation sur-vivability between *** life *** effects on critical thermal minima(CT_(min))and maxima(CT_(max))were inconsistent,showing significantly deleterious effects of RCH on adult CT_(max) and CT_(min) and,conversely,beneficial acclimation effects of RCH on larval CT_(min).While no beneficial effects of desiccation acclimation were recorded for desiccation tolerance,fasted individuals had significantly higher survival in adults,whereas fasting negatively affected larval ***,fasted and desiccation acclimated adults had significantly higher starvation tolerance,showing strong evidence for *** results show context-dependent ISR traits that may promote *** fitness and *** the frequent overlapping occurrence of these divergent stressors,ISR reported here may thus partly elucidate the observed rapid global spread of *** into more stressful environments than *** information is vital in determining the underpinnings of multistressor responses,which are fundamental in forecasting species responses to changing environments and management responses.

关键词： acclimation cross-talk cross-tolerance invasive species thermal tolerance tomato leaf miner

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基于旋量理论的冗余机械臂避奇异算法研究

微特电机 2024年第9期52卷 65-70页

作者：刘一帆李莉吕磊李昀佶中国电子科技集团公司第二十一研究所上海200233

针对冗余自由度机械臂的奇异性规避问题进行了研究,对基于旋量理论对7自由度机械臂进行运动学建模,分析了机械臂的奇异性,并根据机械臂最小奇异值作为奇异性优化指标,推导了避奇异的机械臂速度级逆运动学算法。根据速度级逆运动学算法... 详细信息

针对冗余自由度机械臂的奇异性规避问题进行了研究,对基于旋量理论对7自由度机械臂进行运动学建模,分析了机械臂的奇异性,并根据机械臂最小奇异值作为奇异性优化指标,推导了避奇异的机械臂速度级逆运动学算法。根据速度级逆运动学算法进行避奇异的路径规划实验,实验结果表明,逆运动学算法具有良好的精度,验证了避奇异算法的有效性,为冗余机械臂的运动规划奠定了基础。

关键词：旋量冗余机械臂逆向运动学避奇异路径规划

The green tide in Yingkou,China in summer 2021 was caused by a subtropical alga——Ulva meridionalis(Ulvophyceae,Chlorophyta)

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Journal of Oceanology and limnology 2022年第6期40卷 2354-2363页

作者： Xiaoqian lÜ Hao XU Sheng ZHAO Fanzhou KONG Tian YAN Peng JIANG CAS and Shandong Province Key laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China CAS Key laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

The large-scale green tide caused by Ulva has occurred successively in the Yellow Sea since 2007,and new events of green tide also continued to appear in nearby sea areas,indicating an undergoing rapid development of occurrence patterns for harmful macroalgal blooms(HMBs)along coastal *** August 2021,a green tide occurred for the first time in Bayuquan sea area of Yingkou city,liaoning Province in the Bohai *** this study,morphological and molecular approaches were used to identify the causative species as ***,an alien subtropical alga previously found to dominate green tides in the South China *** to the hydrological data of Bayuquan in summer 2021,combined with morphological and developmental observations for this alga,we hypothesized that the disturbance caused by the typhoon In-Fa might have detached the local *** from substrates,especially for those thalli with poorly developed holdfasts,and the ensuing wave-free period with unusually high temperature,which fell in the reported optimum growth temperature for ***,might have provided the favorable conditions for the final bloom of the floating *** is the first report on the bloom of subtropical *** in the north temperate sea zone,indicating that the ecological risk of causing green tides in the future by this rapidly spreading species deserves high attention.

关键词： Bohai Sea green tide holdfast alien species Ulva meridionalis Yingkou

leaf nitrogen resorption is more important than litter nitrogen mineralization in mediating the diversity–productivity relationship along a nitrogen-limited temperate forest succession chronosequence

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Forest Ecosystems 2023年第1期10卷 132-140页

作者： Peng Zhang Xiao-Tao lü Guangze Jin Zhili liu Mai-He li Center for Ecological Research Northeast Forestry UniversityHarbin150040China Forest Dynamics Swiss Federal Institute for ForestSnow and Landscape Research WSLCH-8903BirmensdorfSwitzerland Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang110016China Key laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin150040China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin150040China Key laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China School of life Science Hebei UniversityBaoding071000China

The resorption of nutrients by plants before litter fall and the mineralization of nutrients from plant litter by soil processes are both important pathways supporting primary productivity. While the positive relationship between plant biodiversity and primary productivity is widely accepted for natural ecosystems, the roles of nutrient resorption and mineralization in mediating that relationship remains largely unknown. Here, we quantified the relative importance of nitrogen(N) resorption and N mineralization in driving plant community N investment and the correlation between species diversity and community productivity along an N-limited successional chronosequence of the mixed broadleaved–Korean pine(Pinus koraiensis) forest in northeastern China. leaf N resorption efficiency(NRE) at the community level increased significantly along the successional chronosequence,whereas litter N mineralization rate decreased significantly. leaf NRE was more important than litter N mineralization rate in driving the diversity–productivity relationship. However, higher leaf NRE led to less N mineralization as succession progressed along the chronosequence. Our results highlight the importance of the N resorption pathway rather than the N mineralization pathway for forest N acquisition with community succession,and they provide mechanistic insights into the positive effects of biodiversity on ecosystem functioning. In future forest management practices, we recommend appropriate application of N fertilizer to mitigate the adverse effects of N-poor soil on seedling regeneration during late succession and thus maintain the sustainable development of temperate forest ecosystems.

关键词： Community composition Diversity Ecosystem functioning N cycling N limited Niche complementarity Trade-off

尼拉帕利所致获得性纯巨核细胞性血小板减少性紫癜1例

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肿瘤预防与治疗 2024年第3期37卷 264-270页

作者：郭灵王钇力宋艳芳衷敬华翟聪聪赣南医科大学第一附属医院肿瘤内科江西赣州341000 赣南医科大学第一临床医学院江西赣州341000 赣州市病毒感染相关恶性肿瘤技术创新中心江西赣州341000

尼拉帕利(niraparib)是卵巢癌患者维持治疗中极具代表性的新型聚腺苷二磷酸核糖聚合酶(polyADP-ri-bosepoly-merase,PARP)抑制剂,其罕见不良反应亟需引起临床重视,目前尚无研究表明尼拉帕利在临床治疗过程中导致获得性纯巨核细胞性血小... 详细信息

尼拉帕利(niraparib)是卵巢癌患者维持治疗中极具代表性的新型聚腺苷二磷酸核糖聚合酶(polyADP-ri-bosepoly-merase,PARP)抑制剂,其罕见不良反应亟需引起临床重视,目前尚无研究表明尼拉帕利在临床治疗过程中导致获得性纯巨核细胞性血小板减少性紫癜(acquired amegakaryocytic thrombocytopenic purpura,AATP)。本文通过报道1例因接受尼拉帕利治疗出现AATP的卵巢癌病例,以期提高肿瘤学领域对尼拉帕利罕见不良反应的了解与认识,并为尼拉帕利血液系统不良反应的临床管理提供有效策略。

关键词：尼拉帕利 PARP抑制剂获得性纯巨核细胞性血小板减少性紫癜卵巢癌维持治疗