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Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

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Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu Zhihui Yang weichun Yang Wen Jiang Qi Liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains *** matter is generally assumed to inhibit Fh ***,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation ***,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2.,pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on *** pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin *** high lignosulfonate-content material(lignin:Fh=0.2.,Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh *** addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite *** effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species

Auxiliary Service Dynamic Compensation Mechanism Design for Incentivizing Market Participants to Provide Flexibility in China

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Protection and Control of Modern Power Systems 2024年第5期9卷 112-128页

作者： Yibo Wang Yifan Wang Chuang Liu Yuan Fang Guowei Cai weichun Ge School of Electrical En-gineering Northeast Electric Power UniversityJilin 132012China State Grid Changchun Power Supply Company Changchun 130000China

Because of the rapid growth of new energy and the accompanying considerable uncertainty in the power market,the demand for flexibility in a power sys-tem has risen *** the meantime,the market structure of auxiliary services has changed,resulting in market participants(MPs)benefiting less than expected from providing flexible *** encourage MPs to provide flexibility,this study proposes a dynamic design framework for an auxiliary service compensation *** evaluate the proposed framework,a case study is conducted,examining a peak-shaving service in Liao-ning province in northeast ***,the operational status and limitations of the typical product,the peak-shaving service,in China’s flexibility auxiliary ser-vices market are ***,taking into considera-tion the time value of the flexible products provided by the MPs,a dynamic mechanism for hierarchical compensa-tion of flexibility auxiliary service costs is proposed,and a mathematical model aimed at optimizing the MPs’com-prehensive income is *** results show that,compared with the existing traditional mechanism,the proposed method can effectively guarantee fair remu-neration for the flexibility provider,while easing the tense supply-demand relationship in the flexibility *** Terms—Power system flexibility,auxiliary ser-vices market,peak shaving auxiliary service,differenti-ated operation scenario,dynamic hierarchical compensa-tion mechanism.

关键词： Power system flexibility auxiliary services market peak shaving auxiliary service differentiated operation scenario dynamic hierarchical compensation mechanism

Rhyscotus subrisus Li&Jiang,***.,representing a new record family Rhyscotidae from China(Isopoda:Oniscidea)

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Zoological Systematics 2024年第2期49卷 181-183页

作者： Chonghui Yao Chao Jiang weichun Li College of Agronomy Jiangxi Agricultural UniversityNanchang 330045China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs National Resource Center for Chinese MateriaMedicaChina Academy of Chinese Medical SciencesBeijing 100700China

The family Rhyscotidae Budde-Lund,1904 contains two genera:Rhyscotoides Schmalfuss&Ferrara,1978 and Rhyscotus Budde-Lund,*** date,twenty-one species within the family are known,occurring in the subtropic and tropic regions(Schmalfuss,2.03;Schmidt,2.03;Boyko et al.,2.2.).The members of the family can be recognized by the cephalon with a strongly inflated frons,the antennae with two-jointed flagellum,the maxillae are almost semicircular,the maxillipeds have short palpus and endite,and pleopod exopodites without pseudotracheae(Schmalfuss&Ferrara,1978).Before this study,the members of Rhyscotidae were unknown in *** present research describes a new species of the genus Rhyscotus from Hainan Island,representing a new record of the family Rhyscotidae from China.

关键词： record family

A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

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Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi Qingzhu Li Qingwei Wang Xuelei Yan Bensheng Li Linhai Feng Chao Wu Rongrong Qiu Hongkai Zhang Zhihui Yang weichun Yang Qi Liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily *** surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy *** the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal ***,the four transformation pathways of birnessite are summarized first in this ***,the relationship between transformation pathways and environmental conditions is *** relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization *** AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of *** but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed *** involve isomorphous substitution,redox,complexation,hydration/dehydration,*** transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

Spatiotemporal characteristics of seed rain and soil seed bank of artificial Caragana korshinskii Kom. forest in the Tengger Desert, China

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Journal of Arid Land 2024年第4期16卷 550-566页

作者： SHEN Jianxiang WANG Xin WANG Lei WANG Jiahui QU Wenjie ZHANG Xue CHANG Xuanxuan YANG Xinguo CHEN Lin QIN weichun ZHANG Bo NIU Jinshuai College of Ecological Environment Ningxia UniversityYinchuan 750021China Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwest China Ministry of EducationNingxia UniversityYinchuan 750021China College of Agriculture Ningxia UniversityYinchuan 750021China

Vegetation restoration and reconstruction are effective approaches to desertification control and achieving social and economic sustainability in desert ***,the self-succession ability of native plants during the later periods of vegetation restoration remains ***,this study was conducted to bridge the knowledge gap by investigating the regeneration dynamics of artificial forest under natural *** information of seed rain and soil seed bank was collected and quantified from an artificial Caragana korshinskii *** in the Tengger Desert,*** germination tests were conducted in a laboratory *** analysis of species quantity and diversity in seed rain and soil seed bank was conducted to assess the impact of different durations of sand fixation(60,40,and 2. a)on the progress of vegetation restoration and ecological conditions in artificial *** *** results showed that the top three dominant plant species in seed rain were Echinops gmelinii Turcz.,Eragrostis minor Host.,and Agropyron mongolicum Keng.,and the top three dominant plant species in soil seed bank were ***,Chloris virgata Sw.,and *** restoration period increased,the density of seed rain and soil seed bank increased first and then *** for species richness,as restoration period increased,it gradually increased in seed rain but decreased in soil seed *** was a positive correlation between seed rain density and soil seed bank density among all the three restoration *** species similarity between seed rain or soil seed bank and aboveground vegetation decreased with the extension of restoration *** shape of the seeds,specifically those with external appendages such as spines and crown hair,clearly had an effect on their dispersal,then resulting in lower seed density in soil seed *** addition,precipitation was a crucial factor in promoting rapid germination,also resulting in lower seed density in soi

关键词： ecological restoration soil seed bank seed rain artificial forest vegetation desertification Caragana korshinskii Tengger Desert

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三嗪类大分子高效成炭剂的制备

山东化工 2017年第7期46卷 7-9页

作者：王灏陈琦王瑞菲岳涛邢文国冯维春山东艾孚特科技有限公司山东邹城2375171 山东省水相有机合成及高效清洁分离工程技术研究中心山东济南250014

以三聚氯氰、乙醇胺和1,3-丙二胺为主要原料,制得了一种新型的三嗪类大分子高效成炭剂。利用红外光谱和热失重对产品的结构和性能进行分析,结果表明,成炭剂被成功制备且具有较好的热稳定性和成炭性。

关键词：三聚氯氰乙醇胺丙二胺三嗪类成炭剂

葡萄园喷雾牵引车翼型塔板仿真分析与优化设计

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北京化工大学学报（自然科学版） 2024年第3期51卷 98-106页

作者：魏彬陈伟春马聪北京化工大学机电工程学院北京100029 宁夏农林科学院农业经济与信息技术研究所银川750000

针对宁夏贺兰山区域葡萄种植环境与作物冠层特征,设计了一种带有浮动结构的翼型塔板导流装置,其浮动结构可依据不同生长时期的葡萄作物高度进行调整。利用计算流体力学(CFD)软件对塔板气流场进行仿真分析,以翼型浮动塔板出风口处高速气... 详细信息

针对宁夏贺兰山区域葡萄种植环境与作物冠层特征,设计了一种带有浮动结构的翼型塔板导流装置,其浮动结构可依据不同生长时期的葡萄作物高度进行调整。利用计算流体力学(CFD)软件对塔板气流场进行仿真分析,以翼型浮动塔板出风口处高速气流区域的面积最大值为目标,通过正交分析获得浮动结构与固定结构最佳优化导流几何参数与导风锥参数。在塔板优化结果的基础上,针对浮动结构可调极限角度进行仿真分析,建立风送塔板结构仿真模型,得出其气流汇集的离地高度范围与有效喷施距离。按照设计参数加工装配塔板浮动结构,结合样机完成喷药效能试验。以建立的模型指导各时期葡萄的施药工作,为精准施药提供技术基础。试验结果表明,塔板气流场分布特点与仿真结果基本符合,风送塔板结构仿真模型可靠。

关键词：风送喷雾机流体仿真气流场导流结构

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三聚氰胺类无卤阻燃剂研究进展

山东化工 2017年第1期46卷 49-53页

作者：李培培岳涛邢文国唐晓婵徐婷王达彤冯维春山东艾孚特科技有限公司山东邹城2375171 山东省水相有机合成及高效清洁分离工程技术研究中心山东济南250014

三聚氰胺(MA)及其盐属于氮系及氮-磷系阻燃剂。三聚氰胺盐集酸源、气源于一体,具有很好的膨胀阻燃效能,是构成膨胀型无卤阻燃剂(IFR)的重要组分。本文主要探讨并研究了三聚氰胺氰尿酸盐(MCA)、三聚氰胺磷酸盐(MP)、三聚氰胺焦磷酸盐(DM... 详细信息

三聚氰胺(MA)及其盐属于氮系及氮-磷系阻燃剂。三聚氰胺盐集酸源、气源于一体,具有很好的膨胀阻燃效能,是构成膨胀型无卤阻燃剂(IFR)的重要组分。本文主要探讨并研究了三聚氰胺氰尿酸盐(MCA)、三聚氰胺磷酸盐(MP)、三聚氰胺焦磷酸盐(DMPY)、三聚氰胺聚磷酸盐(MPP)的性质、合成路线及改性方法。对比分析了MP、DMPY、MPP的作用机理和应用范围,对三聚氰胺盐类膨胀型无卤阻燃剂的发展做出了展望。

关键词：三聚氰胺盐阻燃剂合成

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阻燃剂MCA的合成与改性研究进展

山东化工 2017年第7期46卷 76-78页

作者：陈琦陈贵军唐晓婵李培培岳涛邢文国冯维春山东艾孚特科技有限公司山东邹城237517 山东省水相有机合成及高效清洁分离工程技术研究中心山东济南250014

三聚氰胺氰尿酸盐(MCA),是一种含氮的无卤环保型阻燃剂,广泛应用于工程橡胶材料以及尼龙、丙烯酸乳液、聚四氟乙烯树脂和其他烯烃树脂中。具有阻燃效果好,应用成本低,热稳定性好,加工烟雾小,电性能、机械性能、着色性能佳等优点。本文... 详细信息

三聚氰胺氰尿酸盐(MCA),是一种含氮的无卤环保型阻燃剂,广泛应用于工程橡胶材料以及尼龙、丙烯酸乳液、聚四氟乙烯树脂和其他烯烃树脂中。具有阻燃效果好,应用成本低,热稳定性好,加工烟雾小,电性能、机械性能、着色性能佳等优点。本文综述了国内外MCA合成工艺与改性方法,对阻燃剂MCA的发展做出了展望。

关键词：氰尿酸三聚氰胺合成改性