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The conversion of population coding into sparse coding in mammalian cortex

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The conversion of population coding into sparse coding in ma...

Microscopic phase-field study for oriented diffusion channel effect of nickel-based alloy and phases' effect mechanism

中国神经科学学会第十届全国学术会议

作者： Hong XIE mingyi zhang Ji-Song GUAN Tsinghua-Peking Center for Life Sciences MOE Key Laboratory of Protein SciencesCenter for Epigenetics and Chromatin BiologySchool of Life SciencesTsinghua University

Hebb’s postulation on the formation of neuronal assemblies via co-activated cells has been the foundation for memory encoding studies.However,the direct detection of activity induced stable neuronal assemblies for memory encoding has not been shown.By in vivo tracking the EGFP marked immediate early gene expression in individual neurons in the entire cortical volume,we identified sparse activities in layer II neurons encoding different ’concept’ of tasks,layer III neurons showed non-separated activities.The signal intensity in the sparsely encoded layer II neurons was in proportion to the integration of population activities in layer III neurons.Importantly,the convergence of population activities into the sparse activities was determined by the activities in each neuron during learning trials and was able to be characterized by Hebb’s rule.Such weighted convergence was formed after learning trials and was timely stable for over one month,underlying possible mechanisms for the long-term memory formation.Our results showed the encoding of specific memory traces in layer II neurons by forming stable convergence from the population activities in layer III neurons.

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Science China(Technological Sciences) 2011年第4期54卷 835-840页

作者： YANG Kun CHEN Zheng DONG WeiPing WANG YongXin zhang mingyi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

In this paper,a microscopic phase-field model was used to investigate the effect of the oriented diffusion channel and the phases' effect mechanism for the Ni75Al6.0V19.0 alloy during a phase transformation process.A diffusion channel of V was formed in the [100] direction.The oriented growth of DO22 in this direction,when an elastic misfit stress field existed,forced Al to form a diffusion channel next to DO22,resulting in L12-oriented growth.With an increase in stress,the oriented growth increased initially and then decreased.At a higher stress,the average values of the occupation probability for V atoms became constant later while Al atoms earlier.

关键词：微观相场模型扩散通道镍基合金通道效应机理 Al原子相变过程取向生长

施氮对北方粳稻产量、品质及氮肥利用率的影响

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东北农业科学 2024年第1期49卷 1-6页

作者：姬景红刘双全马星竹郝小雨郑雨赵月刘颖张明怡暴帅黑龙江省黑土保护利用研究院/农业农村部黑土地保护与利用重点实验室/黑龙江省土壤环境与植物营养重点实验室哈尔滨150086

通过两年田间试验,研究了不同氮肥施用处理对龙稻18和绥粳18产量、品质和氮肥利用率的影响。结果表明,施用氮肥增产的原因主要是增加了水稻单位面积有效穗数和穗粒数。各施肥处理中,与目标产量施氮量相比,减施氮肥15%,2022年和2023年龙... 详细信息

通过两年田间试验,研究了不同氮肥施用处理对龙稻18和绥粳18产量、品质和氮肥利用率的影响。结果表明,施用氮肥增产的原因主要是增加了水稻单位面积有效穗数和穗粒数。各施肥处理中,与目标产量施氮量相比,减施氮肥15%,2022年和2023年龙稻18和绥粳18两个品种水稻产量及产量构成因素均未产生显著差异,氮肥利用率分别平均增加了4.52%和5.51%;而采用控释尿素与普通尿素混合施用,龙稻18和绥粳18的穗数平均增加了19.8穗/m^(2)和20.9穗/m^(2),穗粒数平均降低了8.3粒/穗和6.2粒/穗,两处理氮肥利用率差异均不显著,但该施肥方式减少了追肥次数,节约了劳动力。施用氮肥增加了龙稻18的出糙率和整精米率,对绥粳18影响不显著;施用氮肥对两个品种的直链淀粉含量影响不大,显著增加了蛋白质含量,降低了垩白粒率、垩白度和食味评分。同等施氮量条件下,控释尿素与普通尿素混合一次性施用较普通尿素分次施用显著提高了水稻的外观品质,龙稻18垩白粒率和垩白度分别平均降低了1.59%和0.66%,绥粳18垩白粒率和垩白度分别平均降低了0.31%和0.13%,其他各施氮处理的加工品质、营养品质和食味品质之间差异不显著。

关键词：水稻产量品质氮肥利用率

Effect of solute Ce,Mn,and Si on mechanical properties of silicon steel:insights from DFT calculations

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Journal of Iron and Steel Research(International) 2024年第3期31卷 700-709页

作者： Xiang-jun Liu Ji-chun Yang Hui-ping Ren Xiao-bin Jia Ming-yi zhang Chang-qiao Yang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resource Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Inner Mongolia North Heavy Industries Group Co. Ltd.Baotou 014010Inner MongoliaChina Inner Mongolia Metal Material Research Institute Baotou 014010Inner MongoliaChina

The influence of solute Ce,Mn,and Si on the mechanical properties of silicon steel was investigated by first-principles calculation.Ce,Mn,and Si can all be solubilized in Fe matrix.Ce significantly reduces the incompressibility and rigidity of the system but also significantly improves the toughness and machinability.The effect of Mn on mechanical properties of the system is not obvious.Si has a significant effect on the improvement in incompressibility and rigidity but a limited effect on the improvement in toughness and machinability.The metallic bond strength of Fe-Ce,Fe-Mn,and Fe-Si doped systems is weaker than that of the pure Fe system,which can be used to explain the reduction in the incompressibility and rigidity of these doped systems.The relatively high electron cloud density in the doped system may be responsible for the increase in toughness.

关键词： Silicon steel Rare earth First-principles calculation Elastic modulus Electronic structure

Microscopic phase field study of the antisite defect of Ni_3 Al in binary Ni-Al alloys

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 2047-2053页

作者： zhang Jing ,CHEN Zheng,LU YanLi,zhang mingyi & WANG YongXin State Key Laboratory of Solidification Processing School of Material Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China State Key Laboratory of Solidification Processing School of Material Science and Engineering Northwestern Polytechnical University Xi’an China

The temporal evolution feature of a microscopic phase field model is utilized to study the antisite defects of L1 2-Ni 3 Al;this is quite different from other physicist’ interests.There are mainly two points in brief.Firstly,antisite defects Ni Al and Al Ni ,which are caused by the deviation from the stoichiometric Ni 3 Al,coexist in the Ni 3 Al phase.The surplus Ni atom in the Ni-rich side is prone to substitute Al thus producing the antisite defect Ni Al that maintains the stability of the L1 2 structure.In other case,the surplus Al atom in the Al-rich side is accommodated by a Ni sublattice consequently giving rise to antisite defect Al Ni .The calculated equilibrium occupancy probability of Ni Al is much higher than that of Al Ni .This point is generally in line with other theoretical and experimental works.Additionally,both Ni Al and Al Ni have a strong negative correlation to time step during the disorder-order transformation.Since the initial value of Ni Al and Al Ni on each site of the matrix is right at the concentration that we set,we can observe the decrease process of Ni Al and Al Ni from the initial disordered high anti-structure state to their respective equilibrium state,i.***.to the result of the ordering process further coarsening.

关键词： antisite defect L1 2 -Ni 3 Al temporal evolution microscopic phase field model

Antisite defect types and temporal evolution characteristics of D0_(22)-Ni_3V structure:Studied by the microscopic phase field

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Science China(Physics,Mechanics & Astronomy) 2009年第8期52卷 1154-1160页

作者： zhang Jing,CHEN Zheng,zhang mingyi,LAI QingBo,LU YanLi & WANG YongXin School of Material Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China School of Material Science and Engineering Northwestern Polytechnical University Xi’an China

Microscopic phase field simulation is performed to study antisite defect type and temporal evolution characteristic of D022-Ni3V structure in Ni75AlxV25-x ternary system.The result demonstrates that two types of antisite defect VNi and NiV coexist in D022 structure;however,the amount of NiV is far greater than VNi;when precipitates transform from D022 singe phase to two phases mixture of D022 and L12 with enhanced Al:V ratio,the amount of VNi has no evident response to the secondary L12 phase,while NiV exhibits a definitely contrary variation tendency:NiV rises without L12 structure precipitating from matrix but declines with it;temporal evolution characteristic and temperature dependent antisite defect VNi,NiV are also studied in this paper:The concentrations of the both defects decline from high antistructure state to equilibrium level with elapsed time but rise with elevated temperature;the ternary alloying element aluminium atom occupies both α and β sublattices of D022 structure with a strong site preference of substituting α site.

关键词： antisite defect D022-Ni3V microscopic phase field

Novel carbon nanohybrids as highly efficient magnetic resonance imaging contrast agents

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Nano Research 2015年第4期8卷 1259-1268页

作者： Rongli Cui Juan Li Huan Huang mingyi zhang Xihong Guo Yanan Chang Min Li Jinquan Dong Baoyun Sun Gengmei Xing CAS Key Laboratory for Biomedical Effects of Nanomaterial & Nanosafety Institute of High Energy Physics Chinese Academy otScience (CAS) Beijing 700049 China

新奇的碳 nanohybrids 成功地用作一个新磁性的回声成像 MRI 对比代理人基于未修改的 metallofullerenes 被制作了。nanohybrids 显示出更高的 R 1 relaxivity 和更好的使 Gd@C 明亮效果比 82 哦在 T 的 X , 在 vivo 的 1 幅 -wei... 详细信息

新奇的碳 nanohybrids 成功地用作一个新磁性的回声成像 MRI 对比代理人基于未修改的 metallofullerenes 被制作了。nanohybrids 显示出更高的 R 1 relaxivity 和更好的使 Gd@C 明亮效果比 82 哦在 T 的 X , 在 vivo 的 1 幅 -weighted 先生图象。这是从原来的 gadofullerenes 的质子 relaxivity 的结果，它保留了完美的碳笼子结构可能完全那么避免 Gd 的版本 3+ 个离子。第二等的纺纱电子转移松驰机制被建议解释怎么 encaged Gd 碳 nanohybrids 的 3+ 个离子与包围的水分子交往。这条途径为开发高度有效、低的毒性 MRI 对比代理人打开新机会。

关键词：磁共振成像造影剂 MRI造影剂碳分子相互作用笼形结构电子转移高效低毒 Gd

Study of apparent complexing capacities of trace heavy-metals in the Huanghe River Estuary

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Acta Oceanologica Sinica 1988年第1期 82-93页

作者： Sun mingyi, zhang Hao and zhang Zhengbin

-By the electroanalysis method combining the complexation titrating technique with the investigation of ip-Ea* characteristic curves, this paper measures apparent complexing capacities of trace heavy-metals in water samples from the Huanghe River Estuary. The results show that the order of apparent complexing capacities of trace heavy-metals in the samples isCu>Cd>Pb,and that apparent complexing capacities of near shore sample are higher than those far from shore. The effect of ultraviolet irradiation on the dissociation of organic ligands and the adsorption effect of cell walls （cells being treated with acid and seawater respectively） are investigated. The reduction （on electrodes） mechanism of species of trace heavy-metals in seawater is approached by ip-Ea* characteristic curves.

关键词： Cu Study of apparent complexing capacities of trace heavy-metals in the Huanghe River Estuary

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高效双通道型Trombe墙冬季热性能分析

太阳能学报 2022年第12期43卷 112-118页

作者：李佩家刘慧芳余本东张铭驿王瑜南京工业大学城市建设学院南京211816 灾害环境人员安全安徽省重点实验室合肥230602

针对传统Trombe墙冬季供热效率不高、夏季过热等问题,提出一种高效双通道型Trombe墙系统,对该系统在冬季时的热性能和采暖效果进行实验研究。结果表明,高效双通道型Trombe墙热效率是传统Trombe墙的1.6~3.4倍,室内温度相比于传统Trombe... 详细信息

针对传统Trombe墙冬季供热效率不高、夏季过热等问题,提出一种高效双通道型Trombe墙系统,对该系统在冬季时的热性能和采暖效果进行实验研究。结果表明,高效双通道型Trombe墙热效率是传统Trombe墙的1.6~3.4倍,室内温度相比于传统Trombe墙可升高0.7~5.7℃。其中,当总通道厚度为0.5 m,外通道为0.2 m,隔热板形状为凹凸板时热效率最高为31%,此时室内温度可达21.7℃。此外,在实验研究基础上建立高效双通道型Trombe墙的传热模型,并验证其准确性。

关键词：被动太阳能建筑太阳能供热太阳能收集 Trombe墙热效率隔热板