摘要：The inter-agency government information sharing(IAGIS)plays an important role in improving service and efficiency of government ***,there is still no effective and secure way for data-driven IAGIS to fulfill dynamic demands of information sharing between government *** by blockchain and data mining,a data-driven framework is proposed for IAGIS in this ***,the blockchain is used as the core to design the whole framework for monitoring and preventing leakage and abuse of government information,in order to guarantee information ***,a four-layer architecture is designed for implementing the proposed ***,the classical data mining algorithms PageRank and Apriori are applied to dynamically design smart contracts for information sharing,for the purposed of flexibly adjusting the information sharing strategies according to the practical demands of government agencies for public management and public ***,a case study is presented to illustrate the operation of the proposed framework.

摘要：Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted *** address this,this study describes the use of threedimensional(3D)bioprinting technology to construct a 3D model with human hepatocarcinoma SMMC-7721 cells(3DP-7721)by combining gelatin methacrylate(GelMA)and poly(ethylene oxide)(PEO)as two immiscible aqueous phases to form a bioink and innovatively applying fluorescent carbon quantum dots for long-term tracking of *** GelMA(10%,mass fraction)and PEO(1.6%,mass fraction)hydrogel with 3:1 volume ratio offered distinct pore-forming characteristics,satisfactorymechanical properties,and biocompatibility for the creation of the 3DP-7721 *** analysis and quantitative real-time fluorescence polymerase chain reaction(PCR)were used to evaluate the biological properties of the *** with the two-dimensional culture cell model(2D-7721)and the 3D mixed culture cell model(3DM-7721),3DP-7721 significantly improved the proliferation of cells and expression of tumor-related proteins and ***,we evaluated the differences between the three culture models and the effectiveness of antitumor drugs in the three models and discovered that the efficacy of antitumor drugs varied because of significant differences in resistance proteins and genes between the three *** addition,the comparison of tumor formation in the three models found that the cells cultured by the 3DP-7721 model had strong tumorigenicity in nude *** evaluation of the levels of biochemical indicators related to the formation of solid tumors showed that the 3DP-7721 model group exhibited pathological characteristics of malignant tumors,the generated solid tumors were similar to actual tumors,and the deterioration was *** research therefore acts as a foundation for the application of 3DP-7721 models in drug devel

摘要：具有强光学非线性和高稳定性的非线性光学(NLO)有机材料因其潜在的广泛应用而备受关注.本研究中,我们设计并系统地研究了具有超强二阶非线性光学响应的一种新型NLO查尔酮衍生物—1-(4-甲氧基苯基)-3-(4-乙氧基苯基)-2-丙烯基-1-酮(DMPO).合成得到的这种新设计的DMPO仅在5天内即可快速生长出尺寸为10×5×4 mm^(3)的DMPO单晶.这些DMPO晶体由中性有机分子组成,它们在较宽的波段600–1800 nm范围具有高透明性,还拥有适度的光学带隙(2.51 eV),并展现出卓越的抗潮解性能.重要的是,DMPO实测的二次谐波产生(SHG)响应高达基准材料4-(4-二甲氨基苯乙烯基)甲基吡啶对甲苯磺酸盐(DAST)的1.86倍,证实了DMPO具有优良的宏观二阶光学非线性性质.因此,DMPO是集多种优点于一身的一种有机NLO新材料,可广泛应用于NLO领域.

摘要：A combination of hydrogels and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as *** hydrogel patterningwith awell-controlled spatial distribution is typically achieved by embedding sophisticated microstructures to act as a ***,these physical barriers inevitably expose cells/tissues to a less physiologically relevant microenvironment than in vivo ***,we present a novel dissolvable temporary barrier(DTB)strategy that allows robust and flexible hydrogel patterning with great freedom of design and desirable flow stimuli for cellular *** key aspect of this approach is the patterning of a water-soluble rigid barrier as a guiding path for the hydrogel using stencil printing technology,followed by a barrier-free medium perfusion after the dissolution of the *** and multiple tissue compartments with different geometries can be established using either straight or curved DTB *** effectiveness of this strategy is further validated by generating a 3D vascular network through vasculogenesis and angiogenesis using a vascularized microtumor *** a new proof-of-concept in vasculature-on-a-chip,DTB enables seamless contact between the hydrogel and the culture medium in closed microdevices,which is an improved protocol for the fabrication ofmultiorgan ***,we expect it to serve as a promising paradigm for organ-on-a-chip devices for the development of tumor vascularization and drug evaluation in the future preclinical studies.

摘要：随着对X射线成像,特别是对弯曲和不规则物体的三维成像的需求不断增加,高性能柔性闪烁膜的开发引起了人们的极大关注.镧系(Ⅲ)-有机闪烁体由于其在结构设计和光学可调谐方面的巨大灵活性,最近成为一类新的有前途的X射线闪烁体.然而,设计具有高光产额和良好溶液分散性的镧系元素(Ⅲ)-有机闪烁体仍然具有挑战性.本文报道了一种具有高效X射线激发发光(XEL)和良好溶液分散性的铕-钛氧簇合物(Eu-TiOCs)闪烁体.笼状镧-钛氧原子簇核作为X射线吸收剂,产生高能电子并引发二次电子热弛豫.有机配体作为能量转移桥和天线,通过级联能量转移来敏化Ln^(3+);离子的发光.Eu-TiOCs闪烁体表现出高的稳态X射线光产额(高达26,816±2000 photons MeV^(-1)).此外,EuTiOCs闪烁体和聚合物的羟基之间的弱氢键相互作用增强了Eu-TiOCs的溶液分散性,有利于制备低光散射和均匀闪烁膜.铕-钛氧簇与聚合物之间的通过无机簇笼和有机配体之间的协同作用,所得到的柔性闪烁膜对平面和非平面物体都表现出的高空间分辨率和低剂量X射线成像.本工作为进一步设计和制备高性能X射线闪烁体和高分辨率柔性闪烁膜提供了新思路.

摘要：准二维钙钛矿表现出独特的光物理性质,这使它们成为激光技术潜在进步的优秀候选材料.高性能纳秒脉冲激光和放大自发发射(ASE)是实现连续波抽运光电泵浦激光器的关键工艺.然而,在纳秒脉冲激光泵浦下发展准二维钙钛矿ASE或激光仍然存在一些困难,包括表面缺陷浓度高、俄歇复合和能量传递效率低.本文通过无添加剂的Cs^(+)阳离子掺杂策略,可以很好地控制准二维钙钛矿膜的形貌和相分布,从而解决了低n相导致的能量传递途径不足的问题.本文通过快速的能量传递过程揭示了增益性质和载流子复合.基于此,掺杂适当比例Cs^(+)阳离子的PEA_(2)(FA_(0.7)Cs_(0.3))_(2)Pb_(3)Br_(10)钙钛矿膜的净增益系数比原始钙钛矿薄膜提高了近3倍,从而将纳秒激光激发下的放大自发发射阈值降低到1/3.研究结果表明,在准二维钙钛矿中掺杂Cs^(+)可为实现高性能激光器件的相位分布设计提供见解.

摘要：化学取代是有效调节分子电导,产生多通道输运、量子干涉效应和其他机制的关键方法.但分子骨架和侧基之间存在复杂的相互作用,目前仍未被研究清楚.在本工作中,我们结合扫描隧道显微镜裂结实验技术和第一性原理计算方法,深入研究了具有不同σ和π侧基的分子电导.实验结果及理论分析表明,σ侧基的加入引起了分子前线轨道的对称性破缺并加剧了分子内散射,从而导致电导的降低.相反,π侧基引入了额外的电荷传输通道,实现了电荷传输的多通道效应,增加了分子的电导.这些发现为未来分子功能化和分子电子器件的设计提供了坚实的基础.

摘要：针对非仿射离散非线性系统的带干扰轨迹跟踪问题,提出一种直接自适应模糊滑模控制设计。为了获得自适应特性及消除滑模控制抖振,通过使用一个动态模糊逻辑系统(Dynamic fuzzy logical system,DFLS)实现等价控制。DFLS的参数实行在线自调节。用Lyapunov分析方法验证了滑模控制的稳定性,结果表明,整个系统渐近稳定且具备自适应、消除抖振的特点。通过数值仿真和一个2自由度机械臂的应用设计仿真证明了所提出设计的良好性能。

摘要：增材制造技术凭借其生产几何复杂结构(如晶格结构)的能力而广受欢迎.在航天航空和汽车领域轻量化设计中,晶格结构具有极大的优势.众所周知,振动问题是航天航空结构设计广泛关注的问题之一,为了避免结构动力破坏,有必要开展结构振动频率研究,尤其是结构自振频率研究.本文针对一阶频率最大化问题,提出了一种维诺梯度随机晶格结构多尺度优化设计方法.首先,在微观尺度上进行了维诺随机晶格微观结构生成和分析.然后,采用无惩罚密度法进行宏观结构优化.最后,基于得到的相对密度分布和映射关系,重构了全尺度维诺梯度随机晶格结构.数值算例验证了该方法在维诺梯度随机晶格结构设计中的正确性和有效性,振动试验也验证了所提出的多尺度方法的有效性和优化的梯度晶格结构在结构动力响应方面的优势.

摘要：To obtain the peak response at 532nm, narrow-band response GaA1As photocathodes with two GaAIAs ac- tive layers of different aluminum compositions are designed in consideration of the maximum absorptivity and quantum efficiency. The transmission-mode and the corresponding reflective-mode photocathodes are grown by metalorganic chemical vapor deposition. The results indicate that the peak response and the cut-off wavelength occur at 532nm for the two kinds of photocathodes respectively. The response of the reflection-mode photoeath- ode is an order of magnitude higher than that of the transmission-mode photocathode, whereas the better growth quality and the thicker second GaAIAs active layer can improve the transmission-mode response.