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Isotherm and kinetic studies on the adsorption of humic acid molecular size fractions onto clay minerals

Acta Geochimica 2019年第6期38卷 863-871页

作者： Mohamed E.A.El-Sayed Moustafa M.R.Khalaf james a.rice Department of Chemistry and Biochemistry South Dakota State UniversityBrookingsSD 57007USA Soils Waterand Environmental Research InstituteAgriculture Research CenterEl-GizaEgypt Chemistry Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt

Humic acid(HA)can adsorb onto mineral surfaces,modifying the physicochemical properties of the ***,understanding the sorption behavior of HA onto mineral surfaces is of particular interest,since the fate and transport of many organic and inorganic contaminants are highly correlated to HA adsorbed onto clay *** to the extreme heterogeneity of HA,the extracted IHSS Leonardite humic acid(LHA)used in this work was fractionated using an ultrafiltration technique(UF)into different molecular size fractions(Fr1,>0.2μm;Fr2,0.2 pm-300,000 daltons;Fr3,300,000-50,000 daltons;Fr4,50,000-10,000 daltons;Fr5,10,000-1000 daltons).Equilibrium and the kinetics of LHA and fraction adsorption onto kaolinite and montmorillonite were *** results demonstrated that the maximum adsorption capacity of LHA,Frl,Fr2,Fr3,Fr4,and Fr5 was 5.99,13.69,10.29,7.02,5.9&and 5.09 on kaolinite while it was 8.29,22.62,13.17,8.91,8.62,and 5.69 on montmorillonite,*** adsorption equilibrium data showed that the adsorption behavior of LHA and its fractions could be described more practically by the Langmuir model than the Freundlich *** rate of humic acid fraction adsorption onto clays increased with decreasing molecular size fraction and increasing carboxylic group ***-first-and second-order models were used to assess the kinetic data and the rate *** results explained that LHA and its fractions adsorption on clay minerals conformed more to pseudosecondo rder.

关键词： Kaolinite Montmorillonite Leonardite humic acid Humic acid fractions Kinetics Equilibrium

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腐植酸在溶液中的聚集行为:不同组分的贡献

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腐植酸 2014年第1期 30-36页

作者： Gabriela Chilom Angela S.Bruns james a.rice 张志国南达科塔州立大学化学与生物化学院布鲁金斯999039 华东理工大学化学与分子工程学院上海200237

用表面张力法研究了脂类物质对几种来源不同的腐植酸在水溶液中的聚集行为。通过碱水和有机溶剂萃取相结合的方式,在每种腐植酸中分离出两种类腐植酸组分(HA1和HA2)和一种类脂类组分。HA1代表原始腐植酸中总有机碳近2/3的组分,此类物质... 详细信息

用表面张力法研究了脂类物质对几种来源不同的腐植酸在水溶液中的聚集行为。通过碱水和有机溶剂萃取相结合的方式,在每种腐植酸中分离出两种类腐植酸组分(HA1和HA2)和一种类脂类组分。HA1代表原始腐植酸中总有机碳近2/3的组分,此类物质在碱性溶液中表现出弱表面活性,仅仅能稍微降低水的表面张力。HA2代表腐植酸中几乎1/3的组分,该组分能够显著降低水的表面张力。HA2也与脂类组分紧密相关。与原始腐植酸不同的是,HA2在研究范围内都没有表现出类胶束聚集行为。HA1的聚集行为成为一种意外特性被讨论。由于腐植酸组分与起辅助作用的脂类物质之间发生相互作用引起HA2。

关键词：腐植酸聚集行为脂类组分表面活性

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自组装和化学成分对腐植酸矿化影响的比较

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腐植酸 2015年第5期 29-40页

作者： Moustafa M.R.Khalaf Gabriela Chilom james a.rice 张水勤袁亮美国南达科塔州立大学化学与生物化学系布鲁金斯sd57007 埃及米尼亚大学理学院化学系米尼亚61519 中国农业科学院农业资源与农业区划研究所北京100081

为了定量评估有机质自组装对其抗微生物矿化作用的影响,从风化褐煤、2种泥炭和1种矿质土壤中分离出的腐植酸用作有机质样品,因为其在来源和有机成分性质方面具有广泛的可变性。以苯-甲醇为提取剂,将原始的腐植酸样品分解成为腐植酸组分... 详细信息

为了定量评估有机质自组装对其抗微生物矿化作用的影响,从风化褐煤、2种泥炭和1种矿质土壤中分离出的腐植酸用作有机质样品,因为其在来源和有机成分性质方面具有广泛的可变性。以苯-甲醇为提取剂,将原始的腐植酸样品分解成为腐植酸组分和腐植酸-脂质复合物,用碱溶液从腐植酸-脂质复合物中进一步提取出两性腐植酸组分和脂质组分。根据以上各组分在腐植酸中的准确比例,混合各自固体组分,制成与自组装样品化学成分一致的物理混合物。添加原始的腐植酸及其相应的混合物作为唯一的碳源,使用矿质土壤中分离出的微生物菌群开展独立的有氧培养试验。矿化培养125天后,自组装样品矿化量比相应的物理混合物高70%。13C固态核磁共振光谱所得的碳类型分布和疏水性指数结果表明,自组装样品的矿化程度与其化学成分不相关。物理混合物和组分的矿化程度因化学成分而不同,且存在着烷基碳优先矿化的现象。以上研究结果表明,腐植酸的微生物矿化与其自组装程度有关。

关键词：土壤有机质腐植酸自组装矿化热容量核磁共振量热法

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Reactive optical matter: light-induced motility in electrodynamically asymmetric nanoscale scatterers

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Light(Science & Applications) 2018年第1期7卷 26-32页

作者： Yuval Yifat Delphine Coursault Curtis W.Peterson John Parker Ying Bao Stephen K.Gray Stuart a.rice Norbert F.Scherer james Franck Institute The University of Chicago929 E.57th StreetChicagoIL 60637USA Department of Chemistry The University of Chicago929 East 57th StreetChicagoIL 60637USA Department of Physics The University of Chicago929 East 57th StreetChicagoIL 60637USA Center for Nanoscale Materials Argonne National Laboratory9700 South Cass AvenueArgonneIL 60439USA UniversitéBordeaux CNRS LOMAUMR 5798F-33400 TalenceFrance Department of Chemistry Western Washington University516 High StreetBellinghamWA 98225USA

From Newton’s third law,which is known as the principle of actio et reactio1,we expect the forces between interacting particles to be equal and opposite for closed ***,“nonreciprocal”forces can arise.2 This has been shown theoretically in the interaction between dissimilar optically trapped particles that are mediated by an external field.3 As a result,despite the incident external field not having a transverse component of momentum,the particle pair experiences a force in a direction that is transverse to the light propagation direction.3,4 In this letter,we directly measure the net nonreciprocal forces in electrodynamically interacting asymmetric nanoparticle dimers and nanoparticle structures that are illuminated by plane waves and confined to pseudo one-dimensional *** show via electrodynamic theory and simulations that interparticle interactions cause asymmetric scattering from ***,the putative nonreciprocal forces are actually a consequence of momentum *** study demonstrates that asymmetric scatterers exhibit directed motion due to the breakdown of mirror symmetry in their electrodynamic interactions with external fields.

关键词： asymmetric forces reciprocal

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A full-wave HTS flux pump using a feedback control system

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Superconductivity 2023年第4期8卷 26-33页

作者： james H.P.rice Ben P.P.Mallett Dominic A.Moseley Alexander Petrov Heng Zhang Steven Wray Rodney A.Badcock Paihau-Robinson Research Institute Victoria University of WellingtonLower Hutt 5012New Zealand UK Atomic Energy Authority Culham Science CentreAbingdon OX143DBUnited Kingdom

Transformer‐rectifier flux pumps are DC superconducting power supplies capable of charging superconducting magnets to high currents and stored magnetic ***,we demonstrate a full‐wave superconducting flux pump assembled from high‐temperature superconducting(HTS)wire that utilizes superconducting switches controlled by applied magnetic field.A negative DC offset occurs in the superconducting secondary of the circuit during operation which is related to the output load current.A feedback control system is proposed and demonstrated to account for the negative DC *** the primary current proportional to the load current during operation allowed for the maximum output of the flux pump to be increased from 35 A to more than 275 *** results are reproduced using a coupled electrical‐and magnetic–circuit model formulated in the MATLAB Simulink®package.

关键词： High‐temperature superconductor Flux pump Power supply Circuit modelling High current

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Mental health of the male adolescent and young man: the Copenhagen statement

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World Journal of Pediatrics 2018年第3期14卷 224-232页

作者： Timothy R.rice Lesha D.Shah Pilar Trelles Shih-Ku Lin Dinne Skjaerlund Christensen Andreas Walther Leo Sher Icahn School of Medicine at Mount Sinai 1 Gustave L.Levy PlaceNew YorkNY 10029USA New York University School of Medicine New Y orkNYUSA Taipei City Hospital and T aipei Medical University TaipeiChina Department of Public Health Center for Healthy Aging and Section of En vironmental HealthUniversity of Copenhag enCopenhagenDenmark Biological Psychology TU DresdenDresdenGermany Clinical Psychology and Psy chotherapy University of Zur ichZurichSwitzerland james J.Peters VA Medical Center and Icahn School of Medicine at Mount Sinai New Y orkNYUSA

Background Male adolescents and young men benefit when their mental health care is specialized to match their unique gendered and developmental needs. Sensitivity to the social circumstances of this population is important;additionally, the emerging ability to tailor care through knowledge gleaned from the intersection of psychiatry, neurology, and endocrinol-ogy informs care. Data sources This article summarized the views of six experts in the area of the adolescent and young adult male mental health. These experts were select members of the World Federation of Societies of Biological Psychiatry's Task Force on Men's Mental Health. They convened to present two symposia on the topic of men's mental health at the 13th World Congress of Biological Psychiatry (WCBP) in Copenhagen, Denmark in 2017. Results In these works, a special focus is paid to addictive disorders, disruptive behavior disorders, aggression, and brain development. Collectively, the authors present an argument for the merits of a male-specifi c model of mental health care to advance the overall well-being of this population. Conclusions Men's mental health should be recognized as a social issue as much as a medical issue, with special attention paid to problems such as unemployment, familial disruption, and substance abuse. These problems, and especially those of major societal impact including violence and suicide which are much more frequently the product of male youth and men, should have more male-tailored options for service provision that respond to men's mental health needs.

关键词： Aggression Development Externalizing behaviors Inpatient care Men's mental health Testosterone

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Eco-graphy and the Performative Long Poem:***'s Giscome Road and Nikky Finney's rice

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Journal of Foreign Languages and Cultures 2021年第1期5卷 43-52,156页

作者： james McCorkle Hobart and William Smith Colleges

***'s Giscombe Road and Nikky Finney's rice are arguably book-length poems that construct an environmental consciousness through the lens of Black *** importance in each is the use of material culture-maps,encyclopedia entries,schematic illustrations,and photographs-to construct the ***'s work tends to use photographs as supplements to her work,that is as illustrations which are intended to humanize against the grain of anti-Blackness;however,the materials in Giscombe's collection are parts of a whole,not supplements,but quoted texts albeit utilizing a different visual *** there is a distinction between their use of material culture,Finney and Giscombe nonetheless create eco-graphies-autobiographies that situate and map oneself in a history of ecologies.

关键词： Giscombe Finney ecology autobiography ekphrasis diaspora

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SnO2-reduced graphene oxide nanoribbons as anodes for lithium ion batteries with enhanced cycling stability

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Nano Research 2014年第9期7卷 1319-1326页

作者： Lei Li Anton Kovalchuk james M. Tour Department of Chemistry Rice University 6 I00 Main Street Houston Texas 77005 USA Richard E. Smalley Institute for Nanoscale Science and Technology Rice University 6100 Main Street Houston Texas 77005 USA Department of Materials Science and NanoEngineering Rice University 6100 Main Street Houston Texas 77005 USA

A nanocomposite material of SnO2-reduced graphene oxide nanoribbons has been developed. In this composite, the reduced graphene oxide nanoribbons are uniformly coated by nanosized SnO2 that formed a thin layer of SnO2 on the surface. When used as anodes in lithium ion batteries, the composite shows outstanding electrochemical performance with the high reversible discharge capacity of 1,027 mAh/g at 0.1 A/g after 165 cycles and 640 mAh/g at 3.0 A/g after 160 cycles with current rates varying from 0.1 to 3.0 A/g and no capacity decay after 600 cycles compared to the second cycle at a current density of 1.0 A/g. The high reversible capacity, good rate performance and excellent cycling stability of the composite are due to the synergistic combination of electrically conductive reduced graphene oxide nanoribbons and SnO2, The method developed here is practical for the large-scale development of anode materials for lithium ion batteries.

关键词： lithium ion battery tin oxide graphene oxide nanoribbons energy storage

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Accumulation and Transfer of Cadmium, by Indica.rice Cultivars Fujian Province of China

Accumulation and Transfer of Cadmium, by Indica Rice Cultiva...

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作者： Blessing james 福建农林大学

学位级别：硕士

农田重金属污染是21世纪所面临的主要挑战之一。虽然污水灌溉、农药和磷肥的过量使用能导致农田的重金属污染,但尾矿及来自于采矿业和工厂的废水才是农用土壤中重金属的主要来源。中国产业的快速发展以及对废水、固体废物和废气的不适... 详细信息

农田重金属污染是21世纪所面临的主要挑战之一。虽然污水灌溉、农药和磷肥的过量使用能导致农田的重金属污染,但尾矿及来自于采矿业和工厂的废水才是农用土壤中重金属的主要来源。中国产业的快速发展以及对废水、固体废物和废气的不适当的处理已经引起了农用土壤的重金属污染。农业土壤中镉的污染最为广泛。考虑到粮食作物对人体健康的影响,生态系统和食物链中镉的移动性、溶解性及毒性使得镉成了最受关注的金属之一。在中国,一些省份的大部分农用地和稻田受到了镉的污染,包括湖南和贵州。因此,减少受重金属污染土壤上生产的农产品中重金属的含量是首要的任务。物种中富集镉的能力的基因遗传变异性使得筛选低富集镉能力的基因型成可能。虽然一些研究显示,总体上,相对粳稻品种,大多数籼稻的可食部位能积累更多的重金属,但是籼稻中不同的品种存在差异性。研究福建省主要栽培的水稻品种对重金属的富集能力及转移是很有必要的。对于安全和可持续的作物生产来说,种植和培养可食器官中富集镉能力弱的作物品种是最为经济和有效的方法。本研究的目的包括：(1)确定转移和富集镉能力较低的籼稻品种;(2)揭示镉在土壤-籽粒系统中的转移特性;(3)明确高、低富集能力籼稻品种中镉转移系数的主要机制。对采自福建省不同地区的16种籼稻品种的镉富集能力进行了分析。结果表明,宜香2292的平均土壤镉浓度1.01 mg·kg-1>特优009(0.99 mg·kg11>宜优673(0.93 mg·kg-1)>宜优115 (0.76 mg·kg-1),均超过了国家环境土壤标准(GB15618-1995,0.30 mg·kg-1)规定的农业土壤中镉的限度(0.3 mg·kg-1, pH泉珍10号(0.27mg·kg-1)>扬两优6号(0.25 mg·kg-1)>东联5号(0.23 mg·kg-1)>丰两优1号(0.22mg·kg-1)>培杂泰丰(0.21 mg·kg-1)>宜优99(0.19 mg·kg-1)>纳科1号(0.15 mg·kg-1)>深两优5814,佳福占(0.14mg·kg-1)>Ⅱ优3301 (0.13 mg·kg-1),这些品种的土壤中的镉含量均低于酸性农用土壤容许限值。宜优673的土壤中有效态镉含量的平均值(0.75 mg·kg-1)＞宜香2292 (0.49 mg·kg-1)>宜优115(0.31 mg·kg-1),均高于0.2 mg·kg-1。但是培杂泰丰的土壤有效态镉含量(0.14 mg·kg-1)>天优998 (0.13 mg·kg-1)>扬两优6 (0.12 mg·kg-1)＞丰两优1号(0.11 mg·kg-1)>泉珍10号(0.08 mg·kg-1)>深两优5814、特优009、宜优99、东联5(0.07 mg·kg-1)>纳科1号、Ⅱ优3301、特优627、佳福占(0.06 mg·kg-1),均低于0.2 mg·kg-1。土壤特性和籼稻品种对镉的吸收有轻微的相关关系,而且土壤里面的这些过程不同于植物体内镉的转运机制。另外,土壤中镉的全量和有效态和关系表明,相对于全镉与pH值之间的相关性(r=0.431**)、与有机质之间的相关性(r=0.143*),有效态镉与pH值之间的相关性更高(r=0.552**)。16种籼稻品种籽粒中镉的浓度的平均值按照如下顺序依次降低：宜香2292 (0.69 mg·kg-1)>宜优115 (0.31 mg·kg-1)>宜优673,扬两优6号,(0.22 mg·kg-1)>泉珍10号(0.12 mg·kg-1)>深两优5814 (0.09 mg·kg-1)>丰两优1号、纳科1号(0.08 mg·kg-1)>天优998、特优009、宜优99 (0.07 mg·kg-1)>Ⅱ优3301,、培杂泰丰(0.05 mg·kg-1)>佳福占和东联5号(0.04 mg·kg-1)。这些水稻品种籽粒中镉的含量大小差异达17倍。而这种差异性可能归因于土壤和水稻品种的不同。16种品种的基于0.1 mg·kg-1 DTPA提取态镉的有效镉—籽粒之间的转移系数表明,宜香2292(2.91)的土壤-籽粒的转移系数比最低的培杂泰丰(0.13)高22倍。这说明,不同籼稻品种的籽粒对土壤中镉的积累有较大的差异性。常规水稻品种如东联5号、佳福占和泉珍10号均表现出较低的土壤-籽粒转移系数(<0.76)。杂交水稻的土壤-籽粒转移系数可分为两个部分,宜香2292、宜优673、扬两优6、纳科1号和天优998的土壤-籽粒转移系数均高于0.76,而有7个杂交品种的转移系数小于0.76。常规水稻品种和杂交水稻品种的土壤-籽粒镉转移系数之间没有显著的差异性。我们又对4个筛选的品种(包括传统的和杂交的籼稻品种)进行进一步研究以明确镉在土壤和水稻各部位之间的

关键词：籼稻镉累积能力土壤转移系数水稻籽粒

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Can the grains offer each other helping hands?Convergent molecular mechanisms associated with domestication and crop improvement in rice and maize

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Molecular Plant 2022年第5期15卷 793-795页

作者： Ravi V.Mural james C.Schnable University of Nebraska-Lincoln LincolnNEUSA

The grasses,Poaceae,are an extraordinarily ecologically success-ful clade,with more than 10000 described extant *** grasses include more than 30 domesticated grain crops,ranging from maize(Zea mays),rice(Oryza sativa),and wheat(Triticum aes-tivum),which are collectively responsible for 50%of all calories consumed by humans around the world,to minor and orphan crops such as teff(Eragrostis tef),pearl millet(Pennisetum glaucum),proso millet(Panicum milaceum),and Job's tears(Coix lacryma-jobi)(Glémin and Bataillon,2009).Domestication of grain crops from their wild relatives involved a common suite of phenotypic changes,including loss of seed shattering,loss of dormancy,and increased apical dominance,which are collectively referred to as"domestication syndrome"(Glémin and Bataillon,2009).

关键词： sativa crops collective

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