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Mutual effects of nitric oxide and iron on the growth of marine algae 被引量:11
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作者 LIU Chunying ZHANG Zhengbin CHEN Xiaorui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期100-109,共10页
Experiments on the effects of nitric oxide (NO) and iron on the growth of marine microalgae Skeletonema costatum were conducted. The results are as follows: exogenous NO could increase the growth rate of marine alg... Experiments on the effects of nitric oxide (NO) and iron on the growth of marine microalgae Skeletonema costatum were conducted. The results are as follows: exogenous NO could increase the growth rate of marine algae and raise the biomass remarkably under iron-deficient conditions. But it was a complicated process that the phytoplankton growth was influenced by NO and iron, which was controlled by the NO concentration, the nutrition level of the culture medium and the iron concentration, etc. Meanwhile, the iron concentration in the medium also has a direct influence on the growth and NO release capacity of the algae. Therefore, the effects of NO and iron on the growth of marine phytoplankton were mutual. 展开更多
关键词 nitric oxide (NO) IRON marine algae the mutual effects
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Investigation of mutual effects among additives in electrolyte for plasma electrolytic oxidation on magnesium alloys 被引量:11
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作者 Lingyun An Ying Ma +2 位作者 Le Sun Zhanying Wang Sheng Wang 《Journal of Magnesium and Alloys》 SCIE 2020年第2期523-536,共14页
Plasma electrolytic oxidation(PEO)coatings were prepared on AZ91D magnesium alloys in alkaline silicate-based electrolyte with and without additives.The mutual effects among additives including TiC particles,dispersan... Plasma electrolytic oxidation(PEO)coatings were prepared on AZ91D magnesium alloys in alkaline silicate-based electrolyte with and without additives.The mutual effects among additives including TiC particles,dispersant polyethylene glycol 6000(PEG6000)and anionic surfactant sodium dodecyl sulfate(SDS)were studied based on orthogonal experiment.The content and distribution of TiC deposited in the coatings were measured by EPMA and EDS.The thicknesses,phase compositions,microstructures and corrosion resistances of the codlings were cAarnined by using TT260 eddy current tuickncss gage,XRD,SEM and clcctrochcniical test,respectively.The results show that the experiment design of this study is the key to study the mutual effects among these additives.Each additive and their interactions all remarkably influence TiC content and corrosion resistance of the coatings.Smaller size TiC is much easier to migrate towards the anode,and the interaction between PEG6000 and SDS both effectively prevents its agglomeration and increases the number of its negative surface charges,which further increase the migration rate and the deposited uniformity of TiC and make TiC have more opportunity to deposit in the discharge channel.Thus,when smaller size TiC,PEG6000 and SDS are all added into the electrolyte,they could improve the anti-corrosion property of the coating to the largest extent attributed to higher TiC content and the densest microstructure of the coating. 展开更多
关键词 Magnesium alloys Plasma electrolytic oxidation ADDITIVES mutual effects Orthogonal experiment Corrosion resistance
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Non-isothermal thermogravimetric investigation on mutual effect between bituminite and anthracite in blends for blast furnace injection 被引量:1
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作者 Yun-fei Wu Qing-hai Pang +3 位作者 Zhi-jun He Teng-fei Song Wen-long Zhan Jun-hong Zhang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2019年第8期818-828,共11页
In order to clarify the mutual effect between bituminite and anthracite in blends during industrial combustion, the influence of particle size and heating rate as well as oxygen concentration in atmosphere was analyze... In order to clarify the mutual effect between bituminite and anthracite in blends during industrial combustion, the influence of particle size and heating rate as well as oxygen concentration in atmosphere was analyzed. The results of non-isothermal thermogravimetric analysis indicated that the combustion behavior of blends was of great difference though blends were prepared with the same volatile content of 20%. The catalysis of bituminite to anthracite changed with the thermal and kinetic condition of combustion reaction, and consequently, blends with different collocations were suitable for various combustion environments. Superior combustion properties of some blends were achieved at high heating rates, while others might react faster under high oxygen-enriched atmosphere. Simultaneously, the volume model and unreacted core model as well as random pore model were introduced to fit the experimental data. The kinetic calculation results showed that the combustion of blends at different heating rates all agreed better with that of random pore model in comparison with the other two models, while the apparent activation energy of samples all decreased with the increase in heating rate. The similarity of functional group structure between bituminite and anthracite is closely related to the accordance in com-bustion stage of bituminite and anthracite in blends. 展开更多
关键词 Pulverized COAL injection COAL BLEND mutual effect Kinetics Activation energy Bituminite ANTHRACITE
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Mutual Information and Relative Entropy of Sequential Effect Algebras 被引量:1
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作者 汪加梅 武俊德 Cho Minhyung 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期215-218,共4页
In this paper,we introduce and investigate the mutual information and relative entropy on the sequentialeffect algebra,we also give a comparison of these mutual information and relative entropy with the classical ones... In this paper,we introduce and investigate the mutual information and relative entropy on the sequentialeffect algebra,we also give a comparison of these mutual information and relative entropy with the classical ones by thevenn diagrams.Finally,a nice example shows that the entropies of sequential effect algebra depend extremely on theorder of its sequential product. 展开更多
关键词 sequential effect algebra mutual information relative entropy
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Accurate Fault Location Modeling for Parallel Transmission Lines Considering Mutual Effect 被引量:1
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作者 Hamdy A.Ziedan Hegazy Rezk Mujahed Al-Dhaifallah 《Computers, Materials & Continua》 SCIE EI 2021年第4期491-518,共28页
:A new accurate algorithms based on mathematical modeling of two parallel transmissions lines system(TPTLS)as influenced by the mutual effect to determine the fault location is discussed in this work.The distance rela... :A new accurate algorithms based on mathematical modeling of two parallel transmissions lines system(TPTLS)as influenced by the mutual effect to determine the fault location is discussed in this work.The distance relay measures the impedance to the fault location which is the positive-sequence.The principle of summation the positive-,negative-,and zero-sequence voltages which equal zero is used to determine the fault location on the TPTLS.Also,the impedance of the transmission line to the fault location is determined.These algorithms are applied to single-line-to-ground(SLG)and double-line-to-ground(DLG)faults.To detect the fault location along the transmission line,its impedance as seen by the distance relay is determined to indicate if the fault is within the relay’s reach area.TPTLS under study are fed from one-and both-ends.A schematic diagrams are obtained for the impedance relays to determine the fault location with high accuracy. 展开更多
关键词 New accurate algorithms mathematical modeling fault location scheme diagrams parallel transmission lines mutual effect SLG and DLG faults
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Mutual effects between a gliding arc discharge and a premixed flame
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作者 Jiajian ZHU Le LI +2 位作者 Yifu TIAN Minggang WAN Mingbo SUN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期140-149,共10页
Mutual effects between a gliding arc(GA)discharge at atmospheric pressure and a premixed CH_(4)/air flame were experimentally investigated.Effects of the flame on the GA were studied using simultaneous measurements of... Mutual effects between a gliding arc(GA)discharge at atmospheric pressure and a premixed CH_(4)/air flame were experimentally investigated.Effects of the flame on the GA were studied using simultaneous measurements of the current,the voltage,and the instantaneous images of the plasma columns.The GA in the flame has a thicker and more diffusive plasma column,and it is more frequently ignited at a smaller breakdown voltage than that in the air.The GA extension velocity and the gliding velocity in the flame are larger than those in the air.The electrode voltage drop of the GA discharge in the flame is about 160 V,whereas that in the air is about 220 V.Compared with the GA in the air,the different features of the GA in the flame can be explained by high-temperature,weakly ionized,and species-abundant environment that are generated by the premixed CH_(4)/air flame.Effects of the gliding arc discharge on the premixed flames were demonstrated using planar laser-induced fluorescence of hydroxyl radicals(OH)and formaldehyde(CH_(2)O).OH and CH_(2)O can be formed in the CH_(4)/air mixture in the presence of the GA due to kinetic effects,and the increase of OH and CH_(2)O shows the great potential of the GA for combustion enhancement. 展开更多
关键词 gliding arc premixed flame discharge characteristics plasma-assisted combustion mutual effects planar laser-induced fluorescence(PLIF)
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Mutual Coupling Effect on Spectral Efficiency of 5G Massive MIMO Millimeter Wave Antenna Array
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作者 Ezeddin A. M. Ben Ihrayz 《Open Journal of Energy Efficiency》 2024年第4期101-119,共19页
The fifth generation (5G) wireless communication requires the massive multiple input multiple output (MIMO) technique. The massive MIMO antenna array of the millimeter wave (mm-wave) is recognized as a key enabler bec... The fifth generation (5G) wireless communication requires the massive multiple input multiple output (MIMO) technique. The massive MIMO antenna array of the millimeter wave (mm-wave) is recognized as a key enabler because of its high spectral efficiency. The higher the frequencies of the RF signal, the lower the distance it travels in free space caused by path loss, and it is more easily absorbed by obstacles, which are needed for high-gain transmitters. The advantage of the physical properties of higher New Radio (NR) frequencies is that 5G can utilize more spectrum, more antennas, and higher-order modulation schemes. The massive antennas and radio frequency chains improve the implementation of the cost of 5G wireless communication systems and result in an intense mutual coupling effect among antennas because of the limited space for deploying antennas. The upper bound of the effective capacity is derived for 5G multimedia massive MIMO communication systems. Two antennas that receive diversity gain models, the mutual coupling matrix, and the spacing antenna distance are built and analyzed. The impacts and affections of the antenna spacing the number of antennas, the quality-of-service (QoS) statistical exponent, and the number of independent incident directions on the upper effective capacity of 5G multimedia massive MIMO communication systems are analyzed. It is shown that for MIMO systems with compact transmit antenna arrays, the mutual coupling seriously degrades system capacity to mitigate the capacity degradation. In case of improvement in the mutual coupling by 99%, the system performance is kept stationary and enhances system capacity. However, the improvement of the mutual coupling is still about 87.5% today, which means the mutual coupling should be considered in 5G massive MIMO networks. 展开更多
关键词 mutual Coupling Antenna Array Massive MIMO Spectral Efficiency effective Capacity MULTIUSER Multipath Directions Scattering Matrix Steering Matrix
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青藏高原植被与气候互馈效应敏感性分析及未来植被变化预估
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作者 王惠平 管琴 +5 位作者 曹晓云 申燕玲 沈晓燕 孙树娇 权晨 周秉荣 《生态学报》 北大核心 2026年第5期2611-2625,共15页
基于多源数据,利用滞后相关和Liang-Kleeman信息流分析了2000—2018年0—6个月时滞情况下青藏高原不同植被类型分区中植被归一化指数(NDVI)和降水/气温之间的互馈效应,弥补了以往诸多研究缺乏方向性和定量验证的不足,预估了2025—2100年... 基于多源数据,利用滞后相关和Liang-Kleeman信息流分析了2000—2018年0—6个月时滞情况下青藏高原不同植被类型分区中植被归一化指数(NDVI)和降水/气温之间的互馈效应,弥补了以往诸多研究缺乏方向性和定量验证的不足,预估了2025—2100年SSP126、SSP245、SSP370和SSP585情景下NDVI演变趋势,结果如下:(1)植被对气候因子的响应存在滞后1—3个月的显著正向调控(P<0.05),即降水增加/气温上升会促进后期NDVI增大,反之抑制;其中,对降水的响应更敏感,NDVI滞后1个月响应敏感性最高(信息流-0.32)、滞后2个月响应范围最广(占高原的11.52%),而气温累积效应更强,NDVI滞后2个月响应敏感性最强(信息流-0.24)、滞后3个月响应范围最广(占高原的16.84%);敏感区集中在青藏高原东部边坡及藏南谷地的草甸、灌丛、草原、针叶林分布区,其中草甸和灌丛优先响应;(2)反观植被对气候因子的反馈,表现为“短期协同、长期制衡”特征,且对气温的反馈强度和范围显著高于降水;同期及气候因子滞后1个月时呈显著正向调控(P<0.05),范围分别约20%(降水)和25%(气温),滞后6个月出现反向调控,即NDVI增减会牵制滞后6个月降水减少(增加)/气温下降(上升),作用范围分别为5.92%(降水)和15.86%(气温);(3)植被-气候间存在滞后1个月特征的正反馈效应,降水增加/气温上升会促进滞后1个月高原东部边坡约13%的区域NDVI显著增大,此调控过程又有利于滞后1个月的降水增大/气温上升,反之亦然;(4)未来2025—2100年期间,上述四种情景下青藏高原NDVI增长速率分别为7.45×10^(-4)/10a、1.60×10^(-3)/10a、2.34×10^(-3)/10a和3.45×10^(-3)/10a,高原东南部绿化趋势显著(P<0.05),中期(2061—2080年)、后期(2081—2100年)藏北高原部分草原以及藏南谷地、三江源自然保护区和青海湖流域的部分草甸,可能将面临退化风险。 展开更多
关键词 青藏高原 归一化植被指数 降水 气温 互馈效应 未来变化
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提升DOA估计的孔径扩展位移填孔的互质阵列
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作者 王桂宝 刘云龙 +2 位作者 王向辉 余可义 王书振 《电讯技术》 北大核心 2026年第3期446-454,共9页
稀疏阵列因能够降低互耦效应并提供更高自由度(Degrees of Freedom,DOFs),在波达方向(Direction-of-Arrival,DOA)估计中受到广泛关注,但其差分共阵中存在孔洞,限制了均匀自由度(Uniform DOFs,uDOFs),从而降低估计性能。针对这一问题,提... 稀疏阵列因能够降低互耦效应并提供更高自由度(Degrees of Freedom,DOFs),在波达方向(Direction-of-Arrival,DOA)估计中受到广泛关注,但其差分共阵中存在孔洞,限制了均匀自由度(Uniform DOFs,uDOFs),从而降低估计性能。针对这一问题,提出了一种孔径扩展位移互质阵列,并推导出其差分共阵孔洞位置的完整表达式。在此基础上,通过引入3个补充子阵列填补孔洞,构造出孔径扩展位移填孔互质阵列(Aperture-expanded Displacement Hole-filled Co-prime Array,ADHCA)。在相同阵元数条件下,ADHCA相较于其他稀疏阵列获得了更大的uDOFs,数值提升了5%到30%。实验结果表明,ADHCA在低信噪比、低快拍数下以及互耦效应等复杂场景下,其DOA估计性能均优于其他经典稀疏阵列,验证了其在复杂电磁环境中进行高精度DOA估计的有效性与优越性。 展开更多
关键词 稀疏阵列 波达方向估计 互耦效应 差分共阵
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智能反射面通信近邻互耦模型与可调阻抗优化方法
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作者 吴炜 王文鼐 《电子与信息学报》 北大核心 2026年第3期1343-1353,共11页
智能反射面(RIS)通常由大量可编程反射单元密集排布而成,当反射单元间距小于入射信号半波长时,电磁互耦效应会显著影响RIS部署的整体性能。为此,该文针对RIS辅助的无线通信系统,研究基于近邻互耦矩阵的简化信道模型以及可调阻抗优化方... 智能反射面(RIS)通常由大量可编程反射单元密集排布而成,当反射单元间距小于入射信号半波长时,电磁互耦效应会显著影响RIS部署的整体性能。为此,该文针对RIS辅助的无线通信系统,研究基于近邻互耦矩阵的简化信道模型以及可调阻抗优化方法。首先,依据互阻抗强度随间隔单元数增加而快速衰减的电磁特性,提取紧邻和次紧邻互耦参数,并结合对应的映射矩阵构建近邻互耦矩阵;其次,在远场条件下,基于等效耦合距离对收发端与RIS间互阻抗计算表达式进行简化,进而建立低复杂度互耦感知信道模型。进一步,基于简化模型并采用阻抗分解法,推导RIS可调阻抗的最优闭式解,其求解复杂度显著低于诺伊曼级数近似算法,并且不受反射单元间距和数量影响。仿真结果表明,所提信道模型和阻抗优化方法在反射单元间距小于等于1/4信号波长时具备较高的准确性和有效性。 展开更多
关键词 智能反射面 互耦效应 信道建模 可调阻抗优化
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中国新质生产力与经济韧性耦合协调时空演化及影响因素
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作者 祝宝基 侯仁勇 张权 《统计与信息论坛》 北大核心 2026年第4期44-57,共14页
厘清新质生产力与经济韧性的交互关系,动态掌握其协调演化特征,对于加快培育新质生产力、推动中国经济高质量发展具有重要意义。基于二者的评价指标体系,采用耦合协调度模型、核密度估计、空间相关性分析和空间计量模型,揭示了2014—202... 厘清新质生产力与经济韧性的交互关系,动态掌握其协调演化特征,对于加快培育新质生产力、推动中国经济高质量发展具有重要意义。基于二者的评价指标体系,采用耦合协调度模型、核密度估计、空间相关性分析和空间计量模型,揭示了2014—2023年中国新质生产力与经济韧性耦合协调发展的时空演化特征及影响因素。研究发现:(1)二者整体均呈稳步上升态势,耦合协调度逐步形成两极分化格局,区域离散性增强,绝对差距扩大;(2)耦合协调度的空间差异显著,总体呈现“东高西低”分布,空间依赖性稳定,形成以长三角为核心的东部沿海“H-H”型集聚区,以内蒙古、新疆和吉林为核心的西部和东北“L-L”型集聚区;(3)新质生产力与经济韧性存在显著的互促效应,且前者对后者的促进作用更强。新质生产力对转型与发展能力子系统的贡献度最高,经济韧性对新质劳动资料子系统的边际作用最强。虚拟集聚、政府干预、城市经济、市场规模和教学研显著正向促进本地区耦合协调度,而外商投资则表现出抑制效应。政府干预、市场规模和教学研具有正向空间溢出效应,虚拟集聚和外商投资则呈负向空间溢出效应。 展开更多
关键词 新质生产力 经济韧性 耦合协调度 互促效应 空间溢出
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国际中文教育与传播的新理念、新方法、新路径
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作者 赵雅文 崔晓晓 《吉林大学社会科学学报》 北大核心 2026年第1期258-265,272,共9页
国际中文教育是一门新兴的交叉融合性学科,课堂上微观层面的语言文化教学是其核心“点”,活动时中观层面的文化交流互鉴是其展开“面”,往来中宏观层面的讲好中国故事是其综合“体”。国际中文教育应用实践中,涉及所有传播方式,既包括... 国际中文教育是一门新兴的交叉融合性学科,课堂上微观层面的语言文化教学是其核心“点”,活动时中观层面的文化交流互鉴是其展开“面”,往来中宏观层面的讲好中国故事是其综合“体”。国际中文教育应用实践中,涉及所有传播方式,既包括面对面小范围的人际传播,也包括各种不同规模的组织传播,还包括以各类媒体为介质的大众传播。传播5W要素理论、使用与满足理论、符号互动理论、知沟和把关人理论对国际中文教育具有十分重要的指导意义和应用价值。国际中文教育要树立“大传播教育”新理念,充分借鉴和应用传播学相关理论新方法,通过智能传播、设置议程和满足需求三个渠道开辟国际中文教育新路径。 展开更多
关键词 国际中文教育 语言文化教学 文化交流互鉴 讲好中国故事
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非均匀阵列构型设计的最新研究进展
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作者 张时东 范翠玲 《西北师范大学学报(自然科学版)》 2026年第1期1-14,共14页
阵列信号处理是雷达与无线通信等领域的支撑技术,其中波达方向(Direction Of Arrival,DOA)估计是关键研究方向.传统均匀线阵因自由度(Degrees of Freedom,DoF)有限、互耦效应显著及物理规模受限等问题,性能提升面临瓶颈.作为一种突破性... 阵列信号处理是雷达与无线通信等领域的支撑技术,其中波达方向(Direction Of Arrival,DOA)估计是关键研究方向.传统均匀线阵因自由度(Degrees of Freedom,DoF)有限、互耦效应显著及物理规模受限等问题,性能提升面临瓶颈.作为一种突破性解决方案,非均匀线阵通过在有限物理尺度下优化阵元布局,实现了DoF提升、互耦效应抑制与系统功耗优化,从而显著增强了信号参数估计与波束调控能力.本文首先建立阵列信号接收模型,系统阐述DOA估计流程,并据此归纳阵列设计准则与核心术语;其次,综述非均匀阵列的典型设计方法,深入剖析其内在设计机理,并通过仿真实验,对比分析非均匀阵列在不同平台约束条件下的DOA估计性能;最后,针对非均匀阵列在宽频带适应性、混合场源定位及低快拍数估计等方面的关键挑战进行展望,以推动该技术从理论创新迈向深度应用. 展开更多
关键词 非均匀阵列 自由度 互耦效应 波达方向估计 构型设计
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多元方法视角下的中塞卫生合作机制研究
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作者 陆奕斐 吴韬 +3 位作者 陈灿宇 邱隽翔 熊红林 楼佳敏 《卫生软科学》 2026年第1期18-23,共6页
[目的]评估中塞卫生合作的模式特征与实施效果,并探讨该模式对健康丝绸之路建设和区域卫生治理的示范意义。[方法]采用内容分析法、案例分析法和专家访谈法,对中塞卫生合作进行深度剖析。[结果]2012—2024年中塞签署11项卫生合作协议,... [目的]评估中塞卫生合作的模式特征与实施效果,并探讨该模式对健康丝绸之路建设和区域卫生治理的示范意义。[方法]采用内容分析法、案例分析法和专家访谈法,对中塞卫生合作进行深度剖析。[结果]2012—2024年中塞签署11项卫生合作协议,以国家/政府为主要合作主体(54.5%),聚焦疾病防控(36.4%)、科技创新(27.3%)等领域。典型项目如华大“火眼”实验室、中塞天然产物和药物发现“一带一路”联合实验室。2015—2024年中塞医药贸易呈阶梯式增长,体现合作从单向输出向协同互惠升级。专家访谈聚焦于机制构建、技术交流、政策规划、产业协作和公共卫生体系建设。[结论]中塞卫生合作成效显著,呈现出政府主导、危机驱动和双边集中三重特征,构建出基于平等互利原则的新型卫生外交模式,已形成区域辐射效应,为“健康丝绸之路”建设和全球卫生治理体系完善提供了理论支撑和实践基础。 展开更多
关键词 中塞卫生合作模式 实施效果 健康丝绸之路 区域卫生治理 协同互惠
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ACIDIC EFFECT OF RADIATION GRAFTING BETWEEN ACRYLONITRILE AND WOOL
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作者 李崔 赵新 +2 位作者 周自雄 王天雕 陈善明 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第3期168-170,共3页
The acidic effect in grafting of acrylonitrile onto wool fibre under mutual irradiation has been studied. The reactivity of various acids towards graft copolymerization was found as the order: H<sub>2</sub>... The acidic effect in grafting of acrylonitrile onto wool fibre under mutual irradiation has been studied. The reactivity of various acids towards graft copolymerization was found as the order: H<sub>2</sub>SO<sub>4</sub>】HNO<sub>3</sub>】HCl】HClO<sub>4</sub>】HOAC. 展开更多
关键词 GRAFT COPOLYMERIZATION WOOL fibre mutual irradiation Acid effect
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Analytical modeling and approaches of multihelix cables incorporating with interwire mutual contacts
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作者 Zhichao ZHANG Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1633-1654,共22页
This study aims to develop an analytical model based on the curve beam theory to capture the mechanical response of a multihelix cable considering the internal contact displacements.Accordingly,a double-helix cable su... This study aims to develop an analytical model based on the curve beam theory to capture the mechanical response of a multihelix cable considering the internal contact displacements.Accordingly,a double-helix cable subjected to axial tension and torsion is analyzed,and both the line and point contacts between the neighboring wires and strands are considered via an equivalent homogenized approach.Then,the proposed theoretical model is extended to a hierarchical multihelix cable with mutual contact displacements by constructing a recursive relationship between the high-and low-level multihelix structures.The global tensile stiffness and torsional stiffness of the double-helix cable are successfully evaluated.The results are validated by a finite element(FE)model,and are found to be consistent with the findings of previous studies.It is shown that the contact deformations in multihelix cables significantly affect their equivalent mechanical stiffness,and the contact displacements are remarkably enhanced as the helix angles increase.This study provides insights into the interwire/interstrand mutual contact effects on global and local responses. 展开更多
关键词 wordshierarchical multihelix cable mutual contact effect mechanical response effective stiffness
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A Theory of Ratio Selection—Lattice Model for Obligate Mutualism
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作者 Kei-Ichi Tainaka Tsuyoshi Hashimoto 《Open Journal of Ecology》 2016年第6期303-311,共9页
Mutualisms are cooperative interactions between members of different species. We focus on obligate mutualism, where each species cannot survive without the other. From a theoretical aspect, obligate mutualism is simil... Mutualisms are cooperative interactions between members of different species. We focus on obligate mutualism, where each species cannot survive without the other. From a theoretical aspect, obligate mutualism is similar to the relationship between male and female. Empirical data indicate a sex-ratio selection: male and female have a specific ratio in their population sizes. In the present paper, we apply lattice model to obligate mutualism between two species, and present a theory of “ratio selection” which is a generalization of sex-ratio selection. Computer simulations are carried out by two methods: local and global interactions. In the former, interactions occur between neighbouring cells, while in the latter they occur between any pair of cells. Simulations in both interactions show the so-called Allee effect: both species can survive, when both densities are large in some extent. However, we find a large difference between local and global simulations. In the case of local interaction, restriction for survival is found to be extremely severe compared to global interaction. Both species require a proper ratio for their sustainability. This result leads to the theory of ratio selection: when interaction occurs locally, the ratio of both species is uniquely determined. We discuss that the ratio selection explains not only the evolution of endosymbionts from free-living ancestors but also the evolution from endosymbionts to organelles. 展开更多
关键词 Obligate mutualism Population Dynamics Ratio Selection Allee effect Lattice Model Sex-Ratio Selection ENDOSYMBIOSIS
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Mutual-activation effect and hydrogen-bond reconfiguration enabling fast ion-transport and self-healing artificial SEI for ultra-stable zinc anodes
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作者 Haozhong Shi Shaohuan Hong +9 位作者 Weijia Meng Feng Gong Zipu Zhao Peng Zhang Wenlong Cao Xiaobing Li Peng Cui Lei Gou Yue Ma Xiaoyong Fan 《Journal of Energy Chemistry》 2026年第4期565-575,I0014,共12页
Artificial solid electrolyte interphase(SEI)represents a promising strategy for stabilizing Zn electrodes by suppressing dendrite formation and parasitic reactions.However,conventional SEI designs suffer from sluggish... Artificial solid electrolyte interphase(SEI)represents a promising strategy for stabilizing Zn electrodes by suppressing dendrite formation and parasitic reactions.However,conventional SEI designs suffer from sluggish Zn^(2+)transport kinetics and mechanical instability during cycling.Herein,we construct a thin chitosan@alginate(CS@SA,~1.5μm)bilayer SEI on Zn electrodes via electrodeposition.Mutually activated functional groups(-COOH in outer SA and-NH_(2)in inner CS)synergistically(1)facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),(2)block reactive H_(2)O contact with the Zn surface,and(3)establish polymer-chain-accelerated Zn^(2+)transport pathways.Hydrogen-bond reconfiguration endows the CS@SA bilayer with in-situ self-healing and anti-detachment features,dynamically maintaining interfacial integrity.These merits simultaneously enhance the Zn electrode stability and Zn^(2+)migration kinetics.Consequently,the Zn@CS@SA electrode demonstrates a high average Coulombic efficiency(CE)of 99.74%over 1000 cycles at 2 mA cm^(-2)and 1 mAh cm^(-2)in the asymmetric cell.The Zn@CS@SA//MnO_(2)demonstrates a four-fold capacity of Zn//MnO_(2)after 1000 cycles at 2 A g^(-1). 展开更多
关键词 Zn-ion battery Zn electrode mutual activation effect Hydrogen-bond reconfiguration Self-healing Fast ion-transport
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多市场接触与企业供应链战略——基于相互克制视角 被引量:3
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作者 邓新明 周强 刘新韬 《南开管理评论》 北大核心 2025年第7期101-113,共13页
本文试图以探讨多市场接触与企业供应链战略间的关系为切入点,将多市场接触的研究视角由竞争企业间扩展到竞争主体外的第三方,从而为企业在动态的竞争环境下如何采取理性有效的供应链战略提出建议。本文的研究结果如下:(1)多市场接触与... 本文试图以探讨多市场接触与企业供应链战略间的关系为切入点,将多市场接触的研究视角由竞争企业间扩展到竞争主体外的第三方,从而为企业在动态的竞争环境下如何采取理性有效的供应链战略提出建议。本文的研究结果如下:(1)多市场接触与强硬供应商战略之间正相关;(2)多市场接触与强硬经销商战略之间负相关;(3)供应商集中度会削弱多市场接触与强硬供应商战略之间的正向关系;(4)客户集中度会削弱多市场接触与强硬经销商战略之间的负向关系。具体而言,当多市场接触企业面对上游供应商时,竞争企业会选择对上游供应商实施强硬战略;但当面对下游客户时,竞争企业之间会展开激烈的竞争。同时,供应商集中程度越高,企业对供应商的竞争强度会减弱;客户集中程度越高,同类竞争企业间的竞争强度会减弱,但面对经销商的竞争强度会增加。本研究验证了相互克制理论在供应链领域的部分适用,丰富了多市场接触的相关理论研究,并拓展了供应链竞争问题的边界,将边界条件从二元组扩展到三元组,为供应链管理文献提供新的视角。研究对企业高层管理者具有重要启示,为其在多市场竞争环境下的供应链战略选择提供了参考。 展开更多
关键词 多市场接触 供应链战略 相互克制效应 供应商 经销商
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品牌调侃的类型及对品牌传播效果的影响 被引量:1
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作者 谢佩洪 李单萌 +1 位作者 郑明珠 乔添琦 《系统管理学报》 北大核心 2025年第4期1137-1154,共18页
随着新媒体技术的广泛应用,品牌间的互动方式也变得愈发多样化。近几年,品牌开始通过社交媒体采用拟人化的表达方式进行互动,包括一对一、一对多、多对一或轮番调侃的形式,具体表现为互黑、互撩、互捧等行为,这种互动形式被定义为“品... 随着新媒体技术的广泛应用,品牌间的互动方式也变得愈发多样化。近几年,品牌开始通过社交媒体采用拟人化的表达方式进行互动,包括一对一、一对多、多对一或轮番调侃的形式,具体表现为互黑、互撩、互捧等行为,这种互动形式被定义为“品牌调侃”。品牌调侃不仅吸引了消费者关注,还能有效提升品牌传播效果。然而,目前有关品牌调侃的研究仍处于起步阶段,尤其是对其品牌传播效果影响机制的研究较为匮乏,因此,该领域有待进一步深入探究,以丰富品牌调侃的研究内容。本研究聚焦于品牌调侃典型事件,采用多案例研究方法,系统分析品牌调侃对品牌传播效果的作用及其影响机制。研究发现:品牌调侃对品牌传播效果有显著正向影响;品牌认同和品牌体验均在品牌调侃与品牌传播效果中起中介作用;品牌知名度在品牌调侃与品牌传播效果中起调节作用。本研究不仅诠释了品牌调侃对品牌传播效果的影响机制,还拓展了对品牌调侃类型的研究,为后续研究的开展提供了参考借鉴,同时也为品牌调侃实践提供了管理启示。 展开更多
关键词 品牌调侃 品牌互黑 品牌互撩 品牌互捧 品牌传播效果
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