摘要：Physical forces,such as magnetic and mechanical stimulation,are known to play a significant role in the regulation of cell *** the present study,a biomimetic regeneration patch was fabricated using E-jet 3 D printing,which integrates mechanical and magnetic stimulation in a biocompatible"one-pot reaction"strategy when combined with a static magnetic field(SMF).The magneto-based therapeutic regeneration patch induced myoblasts to form aligned and multinucleated myotubes,regulated the expression of myogenic-related genes,and activated the p38αmitogen-activated protein kinase pathway via the initiation of myogenic *** validate the efficiency of the proposed strategy,the regeneration patch was implanted into mice and exposed to a suitable SMF,which resulted in significantly enhanced in vivo skeletal muscle *** findings demonstrated that appropriate external physical stimulation provides a suitable biophysical microenvironment that is conducive to tissue *** method used in the present study represents a promising technique to induce the regeneration of damaged skeletal muscle tis sue.

摘要：A novel type of molecular tweezers with different chiral center and cleft has been designed and prepared by using α- hyodeoxycholic acid as spacer and D/L-amino acid methyl ester as chiral arm attached at 3-position. Their structures were elucidated by ^1H NMR, FTIR and elemental analysis. Their recognition properties for various D/L-amino acid methyl esters were also investigated. The preliminary results indicated that these chiral single-armed molecular tweezers exhibited good recognition ability for D/L-amino acid methyl esters with high association constant （up to 5.24 × 10^3 L mol^-1）.

摘要：目的:提出柴油机噪声品质综合评价方法,解决产品总体噪声品质择优排序问题。创新点:在噪声品质综合评价模型的研究中,将均匀设计抽样与层次分析法相结合,提出一种考虑多因素、多水平的噪声品质主观综合评价GPC-UDS-AHP方法,通过对少量的声样本进行主观评价得到声品质综合评价结果;提出基于偏好序和Bradley-Terry模型的权重计算方法,避免了1-9标度法主观性强和一致性难以满足要求的问题。方法:针对传统的成对比较法难以在声品质主观评价试验中获得评价对象整体感受择优排序的不足,结合均设计抽样法"均匀分散"的特点,提出一种基于分组成对比较法的柴油机声品质主观综合评价方法,确定适合于柴油机声品质主观评价的结构及层次划分,提出基于偏好序和Bradley-Terry模型的各级指标权重计算方法。以采集到的某3款柴油机共375个噪声样本为评价对象,分别利用该方法和等级评分法计算得出3款柴油机的声品质评价综合值。结论:提出的柴油机声品质主观综合评价GPC-UDS-AHP方法可在有效地维持成对比较主观评价试验实施范围的情况下,准确地得到柴油机声品质整体主观感受评价得分的择优排序,可用于实施不同柴油机或N次改进试验的声品质比较和评判。

摘要：In order to develop the Mg-Zn-Ag metallic glasses(MGs)for biodegradable implant applications,the glass formation ability(GFA)and biocompatibility of Mg-Zn-Ag alloys were investigated using a combination of the calculation of phase diagrams(CALPHAD)and experimental *** GFA potentiality of two alloy series,specifically Mg_(96-x)Zn_xAg_(4)and Mg_(94-x)Zn_xAg_6(x=17,20,23,26,29,32,35),was predicted theoretically and then substantiated through experimental testing.X-ray diffraction(XRD)and differential scanning calorimetry(DSC)techniques were used to evaluate the crystallinity,GFA,and crystallization characteristics of these *** results showed that compositions between Mg_(73)Zn_(23)Ag_(4)and Mg_(64)Zn_(32)Ag_(4)for Mg_(96-x)Zn_xAg_4,Mg_(66)Zn_(28)Ag_(6)and Mg_(63)Zn_(31)Ag_(6for)Mg_(94-x)Zn_xAg_(6)displayed a superior ***,the GFA of the Mg_(96-x)Zn_xAg_(4)series was better than that of the Mg_(94-x)Zn_xAg_(6)***,the Mg_(70)Zn_(26)Ag_4,Mg_(74)Zn_(20)Ag_6,and Mg_(71)Zn_(23)Ag_(6)alloys showed acceptable corrosion rates,good cytocompatibility,and positive effects on cell *** characteristics make them suitable for applications in medical settings,potentially materials as biodegradable implants.

摘要：There are various strategies to conduct tumor microenvironment(TME)stimulus-responsive(e.g.,acid,H_(2)O_(2)or glutathione)nanoreactors for increasing the efficiency of chemodynamic therapy(CDT).Among these,the exploitation of adenosine triphosphate(ATP,another overexpressed biomarker in TME)-responsive nanoreactors for tumor CDT is still ***,the ATP-responsive iron-doped CDs(FeCDs)were firstly prepared and then coassembled with glucose oxidase(GOx)to obtain FeCDs/GOx liposomes as ATP-responsive *** TME conditions,the nanoreactors initially released FeCDs and ***,with the existence of ATP,iron ions were rapidly released from the FeCDs to trigger Fenton/Fenton-like reactions for generating·***,the T_(1)-weighted magnetic resonance imaging(MRI)was achieved due to the released iron ***,the GOx converted endogenous glucose in tumor to gluconic acid and H_(2)O_(2)to satisfy the requirement of·OH *** vitro as well as in vivo experiments illustrated that the obtained ATP-responsive CD nanoreactors could be used as a versatile nanotheranostics for simultaneously T_(1)-weighted MRI-guided tumor *** work presents a new ATP-responsive nanoreactor with selfsupplied H_(2)O_(2)for multifunctional nanotheranostic applications.

摘要：A simple method is proposed to design free- form surface for Lambertian extended source. In this method, it can take advantage of the designing method for point source via substituting each incident ray with a dynamically calculated equivalent ray. For each facet on the freeform surface, the equivalent ray emits from the energy weighted average-emitting-position for the corre- sponding incident beam, and redirects into the direction which is determined by a source-to-target mapping. The results of the designing examples show that the light distributions＇ uniformities can be improved by this method, e.g., even the improvement of 59% can be achieved.

摘要：本文主要研究消费者在线购买行为的影响。本文首先从参与强度、消费者类型、购物流程类型和广告点击次数四个维度定义了表征消费者在线购买决策心理特征的消费者介入水平,然后基于消费者介入理论分别从群体水平和个体水平的视角分析消费者介入水平维度对其购物数量和购物时间间隔等行为的影响。以此为基础,本文采用多种机器学习方法构建了消费者在线购买行为预测模型。通过对不同预测模型的比较发现,神经网络回归模型对购物数量预测的误差性最小和拟合度最高,而梯度提升回归模型对购物时间间隔预测的性能最好。同时,通过特征变量的重组设置对比实验,本文验证了在购买行为预测模型中引入介入水平维度的有效性和合理性。研究结果揭示了消费者介入水平对在线购买行为的影响规律,不仅丰富了相关理论,而且对网购平台和商家精确预测消费者购买行为、优化服务策略等方面具有重要的指导意义。

摘要：针对三维空间中多航天器协同捕获机动目标问题,提出一种具有终端角度约束和时间一致性约束的设定时间协同制导律,将视线(Line-of-sight,LOS)角误差和齐射攻击的收敛时间作为一个可提前设定的参数,实现对收敛时间进行设置.构建三维场景航天器−目标运动学模型,在沿视线方向将同时攻击问题转化为一致性问题,提出一种分布式协同制导律,设定时间内使得多个航天器剩余飞行时间相等;在垂直视线方向利用滑模控制方法对制导律进行设计,使得每个航天器的视线角在设定时间内达到期望值.上述制导律中,设计了一种设定时间扩展状态观测器(Predefined-time extended state observer,PTESO)对未知的目标加速度进行估计.数值仿真结果验证了方法的有效性.

摘要：目的以玄武岩复合材料低水平放射性固体废物箱新产品为研究对象,对其力学性能进行研究。方法基于玄武岩复合材料性能,参照《低、中水平放射性固体废物容器钢箱》(EJ1076—2014)的相关标准要求,利用ANSYS有限元软件完成了玄武岩复合材料低水平放射性固体废物箱的结构设计,并根据EJ 1076—2014等标准规则,对其进行了力学计算校核。结果以FB-Ⅲ型固体废物箱为例,其由Q235B的钢结构框架和厚度4.5 mm的玄武岩复合材料箱面组成,利用ANSYS有限元软件中的静力学和显示动力学模块,对此结构的玄武岩复合材料废物箱进行了堆码、顶部起吊、叉举、跌落等力学仿真分析,所得到的力学结果均小于EJ 1076—2014要求的限值。结论玄武岩复合材料低水平放射性固体废物箱新产品的结构设计满足设计要求,其力学评定符合EJ 1076—2014。

摘要：以传递运动和动力为主要功能的齿轮在机械装备中具有举足轻重的作用。与金属齿轮相比,塑料齿轮具有质量轻、运行噪音小、耐磨性好、自润滑性能好、耐腐蚀等诸多优点,而且具有易成型、制造成本低、设计灵活等特点。与传统金属齿轮的成型制造方法相比,塑料齿轮因塑料原料种类及性能差别较大,成型制造方法也有很大差异。通过查阅塑料齿轮相关文献资料,总结了不同塑料齿轮的特点、性能及应用,分析了注塑成型、3D打印和机加工成型等塑料齿轮的主要制造方法。