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An Overview of the Multi-Band and the generalized BCS Equations-Based Approaches to Deal with Hetero-Structured Superconductors

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Open Journal of Microphysics 2018年第2期8卷 7-13页

作者： g. P. Malik Theory group School of Environmental Sciences Jawaharlal Nehru University New Delhi India

We trace the conceptual basis of the Multi-Band Approach (MBA) and recall the reasons for its wide following for composite superconductors (scs). Attention is then drawn to a feature that MBA ignores: the possibility that electrons in such an sc may also be bound via simultaneous exchanges of quanta with more than one ion-species—a lacuna which is addressed by the generalized BCS Equations (gBCSEs). Based on several papers, we give a concise account of how this approach: 1) despite employing a single band, meets the criteria satisfied by MBA because a) gBCSEs are derived from a temperature-incorporated Bethe-Salpeter Equation the kernel of which is taken to be a “superpropagator” for a composite sc-each ion-species of which is distinguished by its own Debye temperature and interaction parameter and b) the band overlapping the Fermi surface is allowed to be of variable width. gBCSEs so-obtained reduce to the usual equations for the Tc and Δ of an elemental sc in the limit superpropagator → 1-phonon propagator;2) accommodates moving Cooper pairs and thereby extends the scope of the original BCS theory which restricts the Hamiltonian at the outset to terms that correspond to pairs having zero centre-of-mass momentum. One can now derive an equation for the critical current density (j0) of a composite sc at T = 0 in terms of the Debye temperatures of its ions and their interaction parameters— parameters that also determine its Tc and Δs;3) transforms the problem of optimizing j0 of a composite sc, and hence its Tc, into a problem of chemical engineering;4) provides a common canopy for most composite scs, including those that are usually regarded as outside the purview of the BCS theory and have therefore been called “exceptional”, e.g., the heavy-fermion scs;5) incorporates s±-wave superconductivity as an in-built feature and can therefore deal with the iron-based scs, and 6) leads to presumably verifiable predictions for the values of some relevant parameters, e.g., the

关键词： Hetero-Structured Superconductors Multi-Band and generalized BCS Equations-Based Approaches Unified Treatment of Cuprates and Fe-Based Superconductors Quest for Clues about Raising Tc

On a New Equation for Critical Current Density Directly in Terms of the BCS Interaction Parameter, Debye Temperature and the Fermi Energy of the Superconductor

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World Journal of Condensed Matter Physics 2013年第2期3卷 103-110页

作者： g. P. Malik Theory group School of Environmental Sciences Jawaharlal Nehru University New Delhi India

Recasting the BCS theory in the larger framework of the Bethe-Salpeter equation, a new equation is derived for the temperature-dependent critical current density jc(T) of an elemental superconductor (sc) directly in terms of the basic parameters of the theory, namely the dimensionless coupling constant [N(0)V], the Debye temperature θD and, additionally, the Fermi energy EF—unlike earlier such equations based on diverse, indirect criteria. Our approach provides an ab initio theoretical justification for one of the latter, text book equations invoked at T = 0 which involves Fermi momentum;additionally, it relates jc with the relevant parameters of the problem at T ≠ 0. Noting that the numerical value of EF of a high-Tc sc is a necessary input for the construction of its Fermi surface—which sheds light on its gap-structure, we also briefly discuss extension of our approach for such scs.

关键词： Critical Current Density BCS Parameters Fermi Energy Elemental/Non-Elemental Superconductors

4-CH_3sc_6H_4NH_2对α-磷酸锆的插层特性

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高等学校化学学报 1998年第11期19卷 1711-1714页

作者：杜以波李峰何静 D.g.Evans 段雪王作新北京化工大学应用化学系英国爱克斯特大学化学系

制备了４－ＣＨ３ＳＣ６Ｈ４ＮＨ２（ＭＭＡ）插层的α－Ｚｒ（ＨＰＯ４）２·Ｈ２Ｏ（α－ＺｒＰ），研究了不同实验条件下ＭＭＡ的插层特性．发现插层反应与ＭＭＡ和α－ＺｒＰ的摩尔比Ｒ有关：（１）当Ｒ＞２时，有插层产物相产生，... 详细信息

制备了４－ＣＨ３ＳＣ６Ｈ４ＮＨ２（ＭＭＡ）插层的α－Ｚｒ（ＨＰＯ４）２·Ｈ２Ｏ（α－ＺｒＰ），研究了不同实验条件下ＭＭＡ的插层特性．发现插层反应与ＭＭＡ和α－ＺｒＰ的摩尔比Ｒ有关：（１）当Ｒ＞２时，有插层产物相产生，但是即使在ＭＭＡ大大过量（Ｒ＝５～９）的条件下，仍然有部分α－ＺｒＰ没有发生插层反应；（２）当Ｒ＜２时，没有插层产物出现，只有α－ＺｒＰ．插层产物的产率与插层方法、α－ＺｒＰ颗粒大小等有关；插层产物的层间距约为２．３６ｎｍ，层间距的大小不随反应物浓度、温度等条件变化．ＭＭＡ在α－ＺｒＰ层板之间以双分子层的形式排列，并且有２种存在状态：一种是它的氨基被α－ＺｒＰ的酸性位质子化，另一种是未被质子化而与α－ＺｒＰ的氢原子以氢键的形式相连，这种不完全的质子化形式和不被插层的α－ＺｒＰ的存在可能与ＭＭＡ相对较弱的碱性有关．

关键词： α-ZrP 胺插层化学 MMA 磷酸锆层柱化合物

Dietary supplementation with curcumin-loaded nanocapsules in lambs:Nanotechnology as a new tool for nutrition

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Animal Nutrition 2021年第2期7卷 521-529页

作者： Hiam Marcon Luiz g.griss Vitor L.Molosse Bruno g.O.Cecere Davi F.Alba Karoline W.Leal gabriela M.galli Carine F.Souza Matheus D.Baldissera Samanta gundel Vitória de A.Bassotto Aline F.Ourique Marcelo Vedovatto Aleksandro S.Da Silva Department of Animal science Universidade Do Estado de Santa Catarina(UDESC)ChapecóSCBrazil graduate Program in Animal science UDESCChapecóSCBrazil Department of Physiology and Pharmacology Universidade Federal de Santa Maria(UFSM)RSBrazil Universidade Franscicana Santa MariaRSBrazil graduate Program in Animal science Universidade Estadual de Mato Grosso Do SulAquidauanaMSBrazil

Curcumin-containing nanocapsule powder formulations have not been used in ruminant feed to date,despite the fact that curcumin is known to be a functional food *** objective of this study was to determine whether ethyl polymethacrylate(Eudragit L-100)nanocapsules loaded with curcumin(N-CU)would improve health and growth of ***-two male Lacaune lambs(body weight[BW]=16±0.99 kg;45 d of age)were randomly assigned to 1 of 4 treatments:T0,T1,T2 and T4,representing supplementation of curcumin at 0,1,2,and 4 mg/kg concentrate,*** animals in each treatment were allocated in 4 pens of 2 lambs each(8 lambs per treatment).The experiment lasted 17 d,with samples and measurements collected on d 0,7,12,and *** T2 lambs had greater average daily gain than T0 *** analysis showed that the ideal dose of N-CU to enhance weight gain was 1.89 mg/kg *** were significant interactions(Pgical variables,particularly for increases in erythrocytes(T2)and re-ductions in counts of leukocytes,neutrophils,and lymphocytes in T1 and *** were significant interactions between treatment×time for total protein,globulin,urea,and triglyceride ***-lation of the antioxidant system was also *** were increased levels of non-protein thiols(NPSH),as well as increased activities of superoxide dismutase(SOD)and glutathione S-transferase(gST)in the supplemented *** of reactive oxygen species(ROS)were lower in the serum of sup-plemented *** general,the 4 mg/kg dose had no positive effects on growth or *** was an unexpected result,given the known properties of *** together,these findings suggest that addition of low concentrations of nanoencapsulated curcumin(T1 and T2)in lamb feed improves health,minimizing oxidative stress and generates anti-inflammatory effects that may have contributed indi-rectly to greater weight *** potentiate the effe

关键词： Antioxidant Anti-inflammatory Curcuma longa Performance Sheep

高分辨电感耦合等离子质谱测定黄连中的微量元素

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光谱学与光谱分析 2003年第6期23卷 1167-1170页

作者：王小逸 Zhu W Witkamp g T 曾衍钧北京工业大学分析测试中心北京100022 荷兰Delft科技大学系统设备实验室北京工业大学生物医学工程研究中心北京100022

文章采用高分辨电感耦合等离子体质谱(HR-ICP-MS)的方法,测定了中草药中四种黄连——味连、雅连、马尾连和胡黄连中的微量元素。结果表明:在所有16种稀土元素中,La,Ce,Nd,gd,Sm,sc含量较高,胡黄连的稀土总量为5.18μg·g^(-1),是所有四... 详细信息

文章采用高分辨电感耦合等离子体质谱(HR-ICP-MS)的方法,测定了中草药中四种黄连——味连、雅连、马尾连和胡黄连中的微量元素。结果表明:在所有16种稀土元素中,La,Ce,Nd,gd,Sm,sc含量较高,胡黄连的稀土总量为5.18μg·g^(-1),是所有四种黄连的最高者,其次是雅连和马尾连,最低的是味连(1.26μg·g^(-1))。而对于与清热解毒有关的金属无素如Mg,Mn,Zn,Ca和Fe元素,雅连中Mg,Mn,Zn的含量最高。高Fe和Ca的含量存在于马尾连和胡连之中。在测定不同提取方法的提取物中发现,只有部分的稀土元素能被醇和水所提取,它们分别是31.6％和4.1％。清热解毒元素的提取率明显高于稀土元素。

关键词：黄连微量元素含量测定高分辨电感耦合等离子质谱

Magnesium activation affects the properties and phosphate sorption capacity of poultry litter biochar

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Biochar 2023年第1期5卷 1117-1130页

作者： Joshua T.Padilla Donald W.Watts Jeffrey M.Novak Vasile Cerven James A.Ippolito Ariel A.Szogi Mark g.Johnson United States Department of Agriculture Agricultural Research ServiceCoastal Plains SoilWater and Plant Research CenterFlorenceSC 29501USA school of Environment and Natural Resources The Ohio State UniversityColumbusOH 43210USA Center for Public Health and Environmental Assessment United States Environmental Protection AgencyCorvallisOR 97331USA

Biochars with a high affinity for phosphorus(P)are promising soil amendments for reducing P in agricultural *** litter(PL)is an abundant biochar ***,PL-derived biochars are typically high in soluble P and therefore require chemical modification to become effective P *** study investigated the effect of magnesium(Mg)activation on extractable P(EP)and P sorption capacities of PL-derived *** was produced at 500-900°C from PL activated with 0-1 M *** differentially aged PL feedstocks were evaluated(1-,3-5-,and 7-9-year-old).Increased Mg activation level and pyrolysis temperature both resulted in EP reductions from the ***,biochars produced at temperatures≥700°C from PL activated with≥0.25 M Mg had negligible EP.X-ray diffractograms indicated that increased Mg loading favored the formation of stable Mg_(3)(PO_(4))_(2) phases while increasing temperature favored the formation of both Mg_(3)(PO_(4))_(2) and Ca_(5)(PO_(4))_(3)*** P sorption capacities(Pmax)of the biochars were estimated by fitting Langmuir isotherms to batch sorption data and ranged from 0.66-10.35 mg g^(−1).Average Pmax values were not affected by PL age or pyrolysis temperature;however,biochars produced from 1 M Mg-activated PL did have significantly higher average Pmax values(pgreater abundance of ***,the results demonstrated that Mg activation is an effective strategy for producing PLderived biochars with the potential ability to reduce P loading into environmentally sensitive ecosystems.

关键词： sorption activation pyrolysis

Influence of Planting Date on the growth and Yield of Different Maturity group of Soybeans in the Southeastern Coastal Plains of USA

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Journal of Agricultural science and Technology(B) 2011年第2期1卷 251-265页

作者： P. Wiatrak g. Chen Department of Entomology Soils and Plant Sciences Clemson University Edisto Research ＆ Education Center Blackville SC29817 USA Department of Land Air and Water Resources University of California Davis 3140 Plant and Environmental Science BuildingOne Shields Avenue Davis CA 95616 USA

Planting date is a critical component of soybean [glycine max （L.） Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of planting date on plant leaf area index （LAI） and normalized difference vegetation index （NDVI） at 60 and 90 days after planting （DAP）, plant height and grain yield, and 2. Determine the optimum planting period by integrating the responses from vegetation growth to yield for soybean maturity group （Mg） IV-VIII under dry land conditions in the Southeastern Coastal Plain. Planting dates were scheduled about 14-days intervals from late April to mid-July （2008） or late July （2009）. greatest grain yield for Mg IV was obtained from planting in around mid-May in both years. The yield was greater for Mg V planted in May and greater for Mg VI-VIII planted in late April and May, but started to decline for planting in early June. Plant LAI and NDVI at 60 DAP were affected by both planting date and precipitation, but were poorly correlated with grain yield. However, plant LAI and NDVI were well correlated with yield and were greater for May planting dates at 90 DAP. These indiccs declined for soybean planted after May. Mature plant height decreased more rapidly with delayed planting. These results indicate that plant growth and yield decreased after May planting. Optimum planting period for all Mgs was early to mid-May.

关键词： Soybean planting date leaf area index normalized difference vegetation index grain yield plant growth.

用Ξ形四能级模型研究非对称耦合量子阱非定域激子复合发光

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物理学报 2004年第4期53卷 1195-1200页

作者：胡振华黄德修华中科技大学光电子工程系

基于Ξ形四能级模型运用密度矩阵方程研究了非对称量子阱中非定域激子复合发光特性 .理论结果表明 :非定域激子复合发光具有双峰特征 ,两峰相对于中心跃迁频率的红移和蓝移量与电子和空穴的振荡频率密切相关 .与单量子阱相比 ,这种频率... 详细信息

基于Ξ形四能级模型运用密度矩阵方程研究了非对称量子阱中非定域激子复合发光特性 .理论结果表明 :非定域激子复合发光具有双峰特征 ,两峰相对于中心跃迁频率的红移和蓝移量与电子和空穴的振荡频率密切相关 .与单量子阱相比 ,这种频率移动对外加电场相当敏感 ,即当外加反向电场作小的变化时 ,两峰有较大的移动 ,表现强量子限域斯塔克效应 .

关键词：非对称耦合量子阱共振隧穿非定域激子量子限域斯塔克效应光谱红移光谱蓝移哈密顿量

Insulin Age-Dependently Modulates Synaptic Transmission and AMPA Receptor Trafficking in Region CA1 of the Rat Hippocampus

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Open Journal of Molecular and Integrative Physiology 2016年第2期6卷 19-33页

作者： Shayna A. Wrighten gerardo g. Piroli Department of Biology Francis Marion University Florence SC USA Department of Pharmacology Physiology and Neuroscience University of South Carolina School of Medicine Columbia SC USA

Insulin induces long-term depression (insulin-LTD) in the CA1 region of the rat juvenile hippocampus. This insulin-LTD may be due in part to internalization of the gluA2 subunit of the AMPA receptor (AMPAR) events that haven’t been studied in the mature rat hippocampus. In our studies, we used hippocampal preparations from juvenile (14 - 25 days) and mature (60 - 90 days) rats to assess insulin modulation of CA1 synaptic transmission and AMPAR trafficking and phosphorylation. Using field potential electrophysiology, we observed that insulin induced LTD in the juvenile hippocampus (as previously reported) in the presence and absence of phosphoinositide 3-kinase (PI3K) activity, but produced no significant long-term changes in the mature hippocampus in the presence of PI3K activity. Interestingly, during PI3K inhibition, insulin did produce LTD in the mature hippocampus. Additionally, insulin induced a long-term decrease in plasma membrane expression of the gluA2 and gluA1 subunits of the AMPAR in the juvenile, but not mature hippocampus. Furthermore, there was a long-term decrease in gluA1 phosphorylation at Serine 845 in the juvenile, but not mature hippocampus. These data reveal that insulin modulation of synaptic plasticity and AMPAR modulation within the hippocampus is age-dependent, suggesting that insulin-regulated behaviors may also show age-dependence. These findings are important largely due to the increased use of insulin as a therapeutic throughout the lifespan. Our data suggest that additional work should be done to determine how this use of insulin throughout different stages of life might affect synaptic function and development.

关键词： Insulin Synaptic Plasticity Synaptic Transmission Long-Term Depression (LTD)