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Chinese Chemical Letters 2018年第12期29卷 1834-1838页

作者： dailei Liu Bo Wan Jianping Qi Xiaochun Dong Weili Zhao Wei Wu yikang dai Yi Lu Zhongjian Chen School of Pharmacy Fudan UniversityKey Laboratory of Smart Drug Delivery of MOE and PLAShanghai 201203China Shanghai Dermatology Hospital Shanghai 200443China Department of Ophthalmology Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200001China

Nanoemulsions(NEs) and nanosuspensions(NSs) show great potential in enhancing the ocular bioavailability of therapeutics through topical delivery. However, transocular fate of intact NEs and NSs is still inconclusive. In this study, an aggregation-caused quenching fluorescent probe is used to track precorneal retention and transocular transportation of intact NEs and NSs, while coumarin 6 is used to mimick the cargo. NEs show superior precorneal retention to NSs. Both the two types of nanocarriers can permeate into but not across the cornea. The smaller NEs(100 nm) permeate better into the cornea than the bigger ones(210 nm). Nanocarriers in the cornea serves as depots. The released cargo molecules can penetrate across the cornea and diffuse into the lens. Moreover, the conjunctiva-scleral route may be potential to deliver drugs to the back of the eye, In conclusion, the study provides useful tools and information in the field of transocular transportation of nanoparticles.

关键词： Transocular transportation Topical administration Aggregation-caused quenching probe Nanoemulsions Nanosuspensions

Parallelogram 3d-4f-5d heterometallic clusters based on trilacunary tungstoantimonates with excellent proton conductivity

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Chinese Chemical Letters 2024年第3期35卷 528-531页

作者： Haiying Wang Han Xu Chaolong Chen Yingjie Zhu yikang Zhang Dongdi Zhang Jingyang Niu Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Molecular SciencesHenan UniversityKaifeng 475004China School of Pharmaceutical Science&Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical UniversityKunming 650500China Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surface and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Two 3d-4f-5d heterometallic cluster-containing polyoxometalates,formulated as Na_(22){(SbW_(9)O_(33))_(4)[La_(3)W_(6)MO_(18)(H_(2)O)_(8)(CH_(3)COO)_(4)]_(2)}·nH_(2)O(abbreviated as La_(6)M_(2),M=Co/Mn)were synthesized and structurally characterized.Single-crystal X-ray diffraction analyses reveal that the polyanions of La_(6)Co_(2)and La_(6)Mn_(2)consist of the uncommon 3d-4f-5d clusters{La_(6)W_(12)Co_(2)}and{La_(6)W_(12)Mn_(2)},which are encapsulated by four trilacunary Keggin tungstoantimonates to form the parallelogram-shaped title compounds.Additionally,the polyanions can be extended into a two-dimensional(2D)frame by the linkage of peripheral Na+ions.The inner space of the 2D layer was filled with water molecules and thus an H-bonded network was formed,which is expected to exhibit a fascinating proton conductivity.The study of water-assisted proton conduction demonstrated that La_(6)Co_(2)and La_(6)Mn_(2)were temperature-and humiditydependent proton conductors,respectively,and the proton conductivities could reach 1.3×10^(-2)and 2.3×10^(-2)S/cm at 65℃and 90%RH conditions.

关键词： Polyoxometalate Parallelogram Heterometallic 3d-4f-5d cluster Proton conductivity

An　Asymmetrical　Structure：　Some　Reflections　On　The　European　Union　Under　The　Maastricht　Treaty

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World Economy & China 1994年第2期2卷 33-38,8页

作者： $$$$Wu yikang and dai Bingyan

ＡｎＡｓｙｍｍｅｔｒｉｃａｌＳｔｒｕｃｔｕｒｅ：ＳｏｍｅＲｅｆｌｅｃｔｉｏｎｓＯｎＴｈｅＥｕｒｏｐｅａｎＵｎｉｏｎＵｎｄｅｒＴｈｅＭａａｓｔｒｉｃｈｔＴｒｅａｔｙＡｎＡｓｙｍｍｅｔｒｉｃａｌＳｔｒｕｃｔｕｒｅ：Ｓｏｍ... 详细信息

ＡｎＡｓｙｍｍｅｔｒｉｃａｌＳｔｒｕｃｔｕｒｅ：ＳｏｍｅＲｅｆｌｅｃｔｉｏｎｓＯｎＴｈｅＥｕｒｏｐｅａｎＵｎｉｏｎＵｎｄｅｒＴｈｅＭａａｓｔｒｉｃｈｔＴｒｅａｔｙＡｎＡｓｙｍｍｅｔｒｉｃａｌＳｔｒｕｃｔｕｒｅ：ＳｏｍｅＲｅｆｌｅｃｔｉｏｎｓＯｎＴｈｅ...

关键词： Maastricht Asymmetrical European An On Reflections Some Structure The Treaty

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证据积累模型的行为与认知神经证据

科学通报 2024年第8期69卷 1068-1081页

作者：刘逸康胡传鹏南京师范大学心理学院南京210024

证据积累模型(evidence accumulation models,EAM)是关于人类决策过程的主要认知模型之一,其假定决策者不断搜集信息并将信息整合成与决策有关的证据,当累积证据量达到某个阈值时做出决策并反应.虽然EAM在研究中得到广泛应用,甚至有研... 详细信息

证据积累模型(evidence accumulation models,EAM)是关于人类决策过程的主要认知模型之一,其假定决策者不断搜集信息并将信息整合成与决策有关的证据,当累积证据量达到某个阈值时做出决策并反应.虽然EAM在研究中得到广泛应用,甚至有研究者认为其已经达到了理论的高原期,但EAM的理论预设并未被严格检验.以最具有代表性的EAM计算模型——漂移扩散模型(drift diffusion model,DDM)为例,其存在5个模型预设:(1)证据积累的普适性,(2)证据积累的选择性,(3)证据以存在噪音的线性方式积累,(4)决策标准恒定,(5)决策与运动执行过程独立.回顾对这5个基本预设进行检验的实证研究,可以发现:尽管DDM被广泛应用于知觉决策、记忆和基于价值的决策任务,但研究者仅验证了证据积累是否存在于知觉决策任务中;证据积累的选择性目前较缺乏实证研究;证据以存在噪音的线性方式积累的预设得到了较多知觉决策实验数据的支持,但在基于价值的决策中其是否成立仍然存在争议;决策标准恒定的预设则存在较大争议;决策独立于反应执行的预设近年来受到关注,但较多实证研究质疑了这一预设.总之,对证据积累模型的预设进行验证的实证研究并不均衡,部分预设的实证证据有限,亟需更多的实证研究进行验证.研究者们需要在解释DDM的结果时保持谨慎.同时,通过对EAM预设进行清晰表述并回顾其实证证据,本研究清晰地表述了模型预设有助于全面而系统地检验模型,从而不断地推动模型的更新与理论的发展,以更好地理解人类认知过程.

关键词：决策证据积累认知建模理论预设

非金融企业部门债务与资源配置优化——基于动态一般均衡模型的量化分析

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中国管理科学 2024年第1期32卷 65-74页

作者：戚逸康中国证券监督管理委员会市场监管一司北京100033

在债务(高杠杆)问题尚未完全解决的情况下,我国经济还面临着结构失衡和增速放缓的局面。债务和经济增长的双重压力倒逼对两者内在联系的研究需要进一步深入。动态一般均衡模型分析显示,债务通过在生产效率不同的经济参与者之间优化资源... 详细信息

在债务(高杠杆)问题尚未完全解决的情况下,我国经济还面临着结构失衡和增速放缓的局面。债务和经济增长的双重压力倒逼对两者内在联系的研究需要进一步深入。动态一般均衡模型分析显示,债务通过在生产效率不同的经济参与者之间优化资源配置,促进资本积累和产出增加,社会福利进而提高。在强制性偿还的条件下,生产均衡条件决定了债务的上限,但在非强制性偿还的条件下,“不太紧”债务上限和生产均衡条件共同决定债务上限。数值模拟显示,债务资本比和资本存量之间呈现出稳健的正U型关系。目前我国33.9%的非金融企业部门债务资本比水平高于数值模拟下的最优水平,所以政策导向上应坚持去杠杆,但资源错配或资源配置无效率问题需重视。

关键词：非金融企业部门债务搜索理论信贷约束杠杆率

Petrogenesis of early Paleozoic granitoids in the North Qinling Orogen,Central China:Implications for crustal evolution in an accretionary orogen

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Geoscience Frontiers 2024年第2期15卷 183-201页

作者： Leran Hao Debin Yang Anqi Wang yikang Quan Xiangyu Yan Shuo Wang College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia(Jilin University) Ministry of Natural ResourcesChangchun 130061China

Accretionary orogens are sites of extensive continental crustal growth and modification.The mechanism by which mafic crust is transformed into silicic melts(i.e.,maturation of continental crust)is important for understanding the formation of the continental crust.The North Qinling Orogen(NQO)is a composite orogenic belt and contains an early Paleozoic accretion-dominated orogenic system,which is ideal for investigating continental crustal maturation.We obtained zircon and monazite U–Pb age and O isotope data,zircon Lu–Hf isotope data,and whole-rock major-and trace-element and Sr–Nd isotope data for early Paleozoic granitoids of the NQO.The granitoids are divided into three groups.Group 1 includes the Taiping tonalite(445±3 Ma),the Manziying syenogranite(445±2 Ma),and the Huoshenmiao granodiorite(436±2 Ma).The Taiping and Huoshenmiao plutons have relatively high SiO_(2)contents(68.64–71.67 wt.%)and Na_(2)O/K_(2)O ratios(1.15–4.19),with enrichments in Rb,Ba,Th,and U and depletions in Nb,Ta,P,and Ti,and they are geochemically similar to sodic arc magmas.The Manziying syenogranite is a peraluminous potassic granite with high K_(2)O contents(4.59–5.27 wt.%).Grantioids from Group 1 have similarly depleted Sr–Nd–Hf–O isotopic features(eHf[t]=+5.9 to+8.8;δ^(18)O=3.98‰–5.41‰),indicative of derivation via partial melting of oceanic arc crust,which suggests that partial melting of oceanic arc crust in a subduction system contributes to the generation of continental crust and causes its maturation.Group 2 consists of the Wuduoshan monzogranite(418±2 Ma)and the Sikeshu granodiorite(423±3 Ma).These plutons have relatively high SiO_(2)(65.59–72.06 wt.%),K_(2)O(3.26–4.79 wt.%),and Al2O3(14.65–16.12 wt.%)contents and Sr/Y(33–87)and(La/Yb)N(23–48)ratios.The Wuduoshan monzogranite has positive zircon eHf(t)(+0.4 to+3.1)and uniformδ^(18)O(6.38‰–8.07‰)values,but the Sikeshu granodiorite has more variable isotopic compositions(eHf[t]=-1.9 to+5.0;δ^(18)O=6.37‰–10.60‰).The Wuduoshan monzogranite and Sikeshu granodiorite have similar who

关键词： Zircon Hf-O isotopes Granite Continental crust Accretionary orogen

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微通道翼型导流肋强化传热数值研究

工程热物理学报 2024年第5期45卷 1431-1439页

作者：张剑飞徐星夏毅康高伟屈治国西安交通大学热流科学与工程教育部重点实验室能源与动力工程学院西安710049

随着电子设备的集成度和功率密度的提高,电子芯片的高功耗和高集成度将使电子设备的散热量不断增加。因此,散热已成为高性能电子设备性能发展的主要瓶颈之一。本文提出了一种含翼型导流肋微通道热沉,翼型导流肋可实现局部加速和冲击掺... 详细信息

随着电子设备的集成度和功率密度的提高,电子芯片的高功耗和高集成度将使电子设备的散热量不断增加。因此,散热已成为高性能电子设备性能发展的主要瓶颈之一。本文提出了一种含翼型导流肋微通道热沉,翼型导流肋可实现局部加速和冲击掺混的双重强化传热作用。采用ANSYS FLUENT数值分析了翼型导流肋的攻角、出射角、长度和数量等主要几何参数对微通道流动传热特性的影响规律。研究发现:相比攻角和出射角,肋长度和肋数量对微通道阻力与传热性能的影响更为显著,强化传热综合性能评价表明本文提出的含翼型分流肋的微通道相比光滑微通道可在相同压降的条件下获得更高的换热量。

关键词：电子器件热管理强化传热微通道翼型导流肋:优化设计

Different bactericidal abilities of plasma-activated saline with various reactive species prepared by surface plasma-activated air and plasma jet combinations

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Plasma Science and Technology 2024年第1期26卷 50-61页

作者：贾怡康李甜会张瑞赵鹏瑜王子丰陈旻郭莉刘定新 State Key Laboratory of Electrical Insulation and Power Equipment Center for Plasma BiomedicineXi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Life Science and Technology Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China

Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive species,which can be regulated by the activation process.In this study,surface plasma-activated air(SAA)and a He+O_(2)plasma jet(Jet)were parallelly combined(the SAA+Jet combination)or sequentially combined(the SAA→Jet combination and the Jet→SAA combination)to prepare plasma-activated saline(PAS).The PAS activated by the combinations exhibited stronger bactericidal effects than that activated by the SAA or the Jet alone.The concentrations of H_(2)O_(2)and NO_(2)^(-)were higher in the PAS activated by the Jet→SAA combination,while ONOO^(-)concentrations were close in the three kinds of PAS and^(1)O_(2)concentrations were higher in the PAS activated by the SAA+Jet combination.The analysis of scavengers also demonstrated that H_(2)O_(2),^(1)O_(2),and ONOO^(-)in the PAS activated by the SAA+Jet combination,and^(1)O_(2)in the PAS activated by the Jet→SAA combination played critical roles in bactericidal effects.Further,the effective placement time of the three PAS varied,and the PAS activated by the Jet→SAA combination could also inactivate 2.6-log_(10)of MRSA cells after placement for more than 60 min.The regulation of reactive species in plasma-activated water via different combinations of plasma devices could improve the directional application of plasma-activated water in the biomedical field.

关键词： plasma-activated water surface plasma-activated air plasma jet bactericidal effect reactive species

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超声波钻谐振控制算法设计及试验验证

哈尔滨工业大学学报 2024年第4期56卷 73-82页

作者：全齐全金亦康张秋葵唐德威邓宗全机器人技术与系统国家重点实验室(哈尔滨工业大学) 哈尔滨150001

为解决小天体表面引力小及温差变化大难以实现锚固的问题,提出以超声波钻作为锚固工具并采用模糊控制和恒流控制相结合的策略,实现了低钻压力和高低温环境条件下的超声波钻钻进锚固。压电驱动的超声波钻将高频电能转化为高频机械振动,... 详细信息

为解决小天体表面引力小及温差变化大难以实现锚固的问题,提出以超声波钻作为锚固工具并采用模糊控制和恒流控制相结合的策略,实现了低钻压力和高低温环境条件下的超声波钻钻进锚固。压电驱动的超声波钻将高频电能转化为高频机械振动,驱动钻具高频破碎岩石,具有极低钻压力的显著优势,尤其适用于弱引力小天体的钻进锚固作业。针对超声波钻的驱动,对超声波钻的谐振控制算法进行研究。首先,建立超声波钻换能器的等效电路模型,在等效模型基础上研究换能器的阻抗特性、负载特性、温度特性和滞后特性。其次,根据超声波钻的工作特性研究谐振频率识别算法、谐振频率跟踪算法和恒电流控制算法,针对谐振频率跟踪算法研究了基于递归最小二乘估计的频率跟踪算法和基于模糊控制的频率跟踪算法,并对实际控制效果进行对比分析。最后,进行常温常压和高低温环境下钻进试验,试验结果表明,在不同温度环境和不同的钻进对象条件下,所设计的谐振控制算法能够实现对超声波钻的稳定驱动。研究结果表明,所提出的模糊控制和恒流控制能够有效的在低钻压力以及不同温度下实现有效钻进。

关键词：小行星附着锚固超声波钻谐振控制递归最小二乘法模糊控制

基于CT扫描的渗流作用下碎石土孔隙结构变化规律研究

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水文地质工程地质 2024年第2期51卷 123-131页

作者：黄达高溢康黄文波河北工业大学土木与交通学院天津300400 长安大学地质工程与测绘学院陕西西安710054

碎石土作为滑坡堆积层的主要组成物质,受动水因素影响,在渗流作用下内部渗透压力的变化导致土颗粒流失,造成细观结构和力学性质随之发生改变,从而影响滑坡整体稳定性。目前,渗流作用下不同渗透压力状态的孔隙结构变化规律研究较少。通... 详细信息

碎石土作为滑坡堆积层的主要组成物质,受动水因素影响,在渗流作用下内部渗透压力的变化导致土颗粒流失,造成细观结构和力学性质随之发生改变,从而影响滑坡整体稳定性。目前,渗流作用下不同渗透压力状态的孔隙结构变化规律研究较少。通过自主设计的渗流装置对碎石土试样开展室内渗流侵蚀试验,并利用CT扫描技术获取试样渗流侵蚀过程的内部孔隙图像数据。通过孔隙识别和参数提取,得到了不同渗流时刻试样内部孔隙率、等效直径等细观参数。构建孔隙网络模型,分析了渗流作用下连通孔隙的孔喉半径、喉道长度和配位数的变化规律。结果表明:水力梯度的逐步升高会改变碎石土内部孔隙分布,土颗粒的流失造成孔隙率增大,孔隙数量先增加后减少,孔隙体积增加;渗流作用下孔隙发生扩张和连通,孔隙之间连通性增强,平均孔喉半径和配位数均随着水力梯度的升高而增加。研究结果可以为碎石土滑坡的预防与治理提供一定的理论支撑。

关键词：碎石土渗流侵蚀 CT扫描孔隙微观结构滑坡