摘要：AIM: To demonstrate the morphology and structure of in vitro reconstructed tissue-engineered human corneal epithelium (TE-HCEP) with seeder cells from an untransfected HCEP cell line. METHODS: The TE-HCEPs were reconstructed in vitro with seeder cells from an untransfected HCEP cell line, and scaffold carriers of denuded amniotic membrane (dAM) in air-liquid interface culture for 3, 5, 7 and 9 days, respectively. The specimens were examined with hematoxylin-eosin (HE) staining of paraffin-section, immunocytochemical staining, scanning and transmission electron microscopy. RESULTS: During in vitro reconstruction of TE-HCEP, HCEP cells formed a 3-4, 6-7 and 8-10 layers of an HCEP-like structure on dAMs in air-liquid interface culture for 3, 5 and 7 days, respectively. But the cells deceased to 5-6 layers and the structure of straified epithelium became loose at day 9. And the cells maintained positive expression of marker proteins (keratin 3 and keratin 12), cell-junction proteins (zonula occludens-1, E-cadherin, connexin 43 and integrin beta 1) and membrane transport protein of Na+-K+ ATPase. The HCEP cells in TE-HCEP were rich in microvilli on apical surface and established numerous cell-cell and cell-dAM junctions at day 5. CONCLUSION: The morphology and structure of the reconstructed TE-HCEP were similar to those of HCEP in vivo. The HCEP cells in the reconstructed TE-HCEP maintained the properties of HCEP cells, including abilities of forming intercellular and cell-extracellular matrix junctions and abilities of performing membrane transportation. The untransfected HCEP cells and dAMs could promisingly be used in reconstruction HCEP equivalent for clinical corneal epithelium transplantation.

摘要：For lessening the weight and volume of flow control system,enlarging the circulation control applying area of angle of attack(AOA),and achieving nice controlling characteristics,a novel lift enhancement method based on dual synthetic jet actuators(DSJAs)and synthetic jet actuator(SJA),and an adaptive proportional integral and differential(PID)algorithm based on radial basis function neural network are *** are uniformly located along the chord to suppress the separation and trailing-edge SJA is applied to achieve the high *** of actuators are modulated to realize the real speed profile and on–off controlling laws of DSJAs are *** simulations show that DSJAs and SJA could suppress the separation completely and move leading-edge stagnation point and trailing-edge separation point downstream even at AOA of 19°,hence achieve the highest lift and nose-down moment augmentation(ΔCl_(max)=0.92,ΔCm_(max)=0.02534),andΔL/D can reach 11.39 at AOA of 18°.Stalling is delayed to more than 19°.Linear lift area and pitch-break angle are both increased to 16°.ΔCl/C_(μ) can reach 76.7,indicating the greatest control *** results of adaptive PID control,whose controlling effects are proved better than PID,indicate that lift could track the objective with the rise time of 0.0325 s and finally keep steady,suggesting the nice stability and rapidness.

摘要：AIM: To evaluate the biological functions of tissue-engineered human corneal epithelium (TE-HCEP) by corneal transplantation in limbal stem cell deficiency (LSCD) rabbit models. METHODS: TE-HCEPs were reconstructed with DiI-labeled untransfected HCEP cells and denuded amniotic membrane (dAM) in air-liquid interface culture, and their morphology and structure were characterized by hematoxylin-eosin (HE) staining of paraffin-sections, immunohistochemistry and electron microscopy. LSCD models were established by mechanical and alcohol treatment of the left eyes of New Zealand white rabbits, and their eyes were transplanted with TE-HCEPs with dAM surface outside by lamellar keratoplasty (LKP). Corneal transparency, neovascularization, thickness, and epithelial integrality of both traumatic and post transplantation eyes were checked once a week by slit-lamp corneal microscopy, a corneal pachymeter, and periodic acid-Schiff (PAS) staining. At day 120 post surgery, the rabbits in each group were sacrificed and their corneas were examined by DiI label observation, HE staining, immunohistochemistry and electron microscopy. RESULTS: After cultured for 5 days on dAM, HCEP cells, maintaining keratin 3 expression, reconstructed a 6-7 layer TE-HCEP with normal morphology and structure. The traumatic rabbit corneas, entirely opaque, conjunctivalized and with invaded blood vessels, were used as LSCD models for TE-HCEP transplantation. After transplantation, obvious edema was not found in TE-HCEP-transplanted corneas which became more and more transparent, the invaded blood vessels reduced gradually throughout the monitoring period. The corneas decreased to normal thickness on day 25, while those of dAM eyes were over 575 mu m in thickness during the monitoring period. A 45 layer of epithelium consisting of TE-HCEP originated cells attached tightly to the anterior surface of stroma was reconstructed 120 days after TE-HCEP transplantation, which was similar to the normal control eye

摘要：研究目的:纳米二氧化钛已是防晒霜、化妆品和光催化剂等的常用成分。纳米二氧化钛的大量应用,已被证明具有潜在的环境负面影响与人体健康风险。如何分析环境中工程纳米二氧化钛的理化性质无疑是认识其潜在风险的关键课题。研究方法:从工程纳米颗粒可用的表征与测定方法(如电镜显微方法、色谱与质谱技术等)的优缺点出发,结合稳定同位素与稀有元素示踪技术来探讨环境中工程纳米二氧化钛颗粒的分析方法。重要结论:环境中工程纳米二氧化钛的表征与测定方法仍需深入的研究,其可靠性需要现有各种分析技术的相互验证、良好的样品预处理技术和参考物质、以及稳定同位素与稀有元素技术示踪的配合。

摘要：针对组合动力空天飞行器宽域爬升过程存在的模态转换、气动参数未知以及外界时变干扰等问题,研究了一种基于飞行包线模态划分的切换控制方案.对飞行器六自由度模型和发动机推力模型进行气动和推力特性分析,给出了模态划分结果和模态转换过渡过程.基于切换信号设计建立了空天飞行器切换系统,设计终端滑模软切换控制策略来保证模态的平稳转换,并利用神经网络和非线性扰动观测器协同处理系统不确定性和外界时变干扰.通过多Lyapunov函数方法对闭环切换系统的稳定性进行了分析,且仿真结果验证了所提方法的有效性.

摘要：微尺度聚合物熔体流动具有明显的尺度效应,模具温度和注射速率是微注塑充填流动的关键影响因素。文中采用微细电火花铣削技术设计分别制造了一模八腔的带有200μm和300μm微孔的注塑模具。以聚丙烯(PP)进行单因素充模流动工艺实验,研究了模具温度和注射速率对直径为200μm和300μm微圆柱充填高度影响规律。结果表明,当模具温度为30℃和注射速率为60%时,直径200μm微圆柱孔的充填高度小于直径300μm微圆柱孔的充填高度,且Ⅰ型腔的微圆柱充填高度大于Ⅱ的充填高度。随着模具温度升高和注射速率增加,2种微孔充填高度差在减小,Ⅰ型腔和Ⅱ型腔之间的充填高度差值也在减小。可见,升高模具温度和增加注射速率可以减少微尺度效应对微圆柱孔充填高度的影响,同时,还可以减小流动不平衡程度。

摘要：水系锌离子电池(AZIBs)作为一种低成本、高安全的新兴且前景广阔的储能技术近年来备受关注。新型MXenes材料由于其独特的结构特征和物理化学性质,如易调节的二维结构、优异的导电性、化学组成多样和可控的表面化学特性,在AZIBs中表现出独特的应用优势。本文全面综述近年来MXenes在AZIBs中应用的研究进展,探讨MXenes应用于AZIBs正负极的结构设计及性能优化策略:在正极方面,MXenes可直接作为活性物质或活性物质前驱体、基体材料,以获得高活性、优异的循环寿命和倍率性能;在负极方面,MXenes可作为锌沉积的二维/三维载体、亲锌基体及锌金属界面保护层,以减缓电化学反应过程中锌金属的腐蚀和枝晶生长。此外,本文也对MXenes基材料在AZIBs中应用的发展方向进行展望。

摘要：利用原位自由基聚合反应设计合成了葡萄糖氧化酶纳米胶囊(nGOx)和负载替拉扎明(TPZ)的介孔二氧化硅纳米胶囊(nMSNs-TPZ),具有交联结构的聚合物壳层赋予GOx与MSNs-TPZ更高的稳定性与更长的瘤内滞留时间.nGOx持续增强的肿瘤乏氧微环境能够促使TPZ转化为具有细胞毒性的自由基,二者协同作用增强了肿瘤治疗的效果.研究结果表明,nGOx与nMSNs-TPZ均具有尺寸均一的球形结构.nGOx在胰蛋白酶、特定温度以及不同pH溶液中的稳定性均有显著提升,并展现出良好的催化活性.nMSNs-TPZ在谷胱甘肽(GSH)存在下能够有效降解,实现TPZ的可控释放.体外细胞实验和体内动物实验均证实,nGOx产生的局部乏氧环境更有利于TPZ发挥作用,两者的协同治疗展现出更优越的抑瘤效果.

摘要：利用应力动态联动式渗透变形试验系统,选用间断级配散粒土材料开展了潜蚀试验,探索了30、60、90 kPa围压条件下土体潜蚀规律,分析了不同围压下细颗粒流失、体积变化及临界水力梯度的变化特征。试验结果表明:在较小围压下,细颗粒易于流失,导致土体孔隙连通性增强,渗流流速显著提高;而较大围压则压缩了土体孔隙,降低了渗透路径通畅性,使得渗透系数明显降低。在低水力梯度时渗流流速与水力梯度呈现非线性变化,但随水力梯度增大逐渐趋向线性,基本符合达西定律;围压增大导致土体潜蚀启动的临界水力梯度提高,二者呈正相关关系。围压对不同阶段细颗粒流失的影响存在差异,但对细颗粒流失总量的影响不显著。较大围压下土体内部颗粒结合更紧密,试样的变形程度更小,而在30 kPa的低围压条件下,试样体积变化曲线呈明显的阶梯式变化。

摘要：浙江省某污水处理厂一期工程处理规模为20×10^(4)m^(3)/d,进水中市政污水、工业废水各占50%左右,采用曝气沉砂池+复合型多级AO+高效沉淀池+臭氧接触MBBR+滤布滤池+次氯酸钠消毒工艺,其中复合型多级AO结合了多级AO和Bardenpho工艺特点。运行结果表明,当进水平均COD、TN、TP分别为366、34.7、6.25 mg/L时,处理出水相应指标分别降至19、7.5、0.13 mg/L,对应去除率分别为95%、78%、98%,出水水质达到浙江省《城镇污水处理厂主要水污染物排放标准》(DB33/2169—2018)表2的准Ⅳ类要求。该工艺抗冲击能力强、出水稳定、处理效率高,可用于出水标准高尤其是需深度去除COD及TN的混合污水处理厂的设计。