Microfluidic 3D Printing Responsive Scaffolds with Biomimetic Enrichment Channels for Bone Regeneration

Tissue-engineered scaffolds have been extensively explored for treating bone defects; however, slow and insufficient vascularization throughout the scaffolds remains a key challenge for further application. Herein, a versatile microfluidic 3D printing strategy to fabricate black phosphorus (BP) incorporated fibrous scaffolds with photothermal responsive channels for improving vascularization and bone regeneration is proposed. The thermal channeled scaffolds display reversible shrinkage and swelling behavior controlled by near-infrared irradiation, which facilitates the penetration of suspended cells into the scaffold channels and promotes the prevascularization. Furthermore, the embedded BP nanosheets exhibit intrinsic properties for in situ biomineralization and improve in vitro cell proliferation and osteogenic differentiation. Following transplantation in vivo, these channels also promote host vessel infiltration deep into the scaffolds and effectively accelerate the healing process of bone defects. Thus, it is believed that these near-infrared responsive channeled scaffolds are promising candidates for tissue/vascular ingrowth in diverse tissue engineering applications.     

Target Positioning Algorithm Based on RSS Fingerprints of SVM of Fuzzy Kernel Clustering

The positioning technology based on receive signal strength (RSS) fingerprints has become one of the hottest research spots with its advantages of simple deployment, low cost, and single parameter. However, in the limited space, the multipath and shadowing, result in poor separability of the fingerprint data, and low accuracy of target localization. In this paper, a novel RSS fingerprints positioning algorithm that is based on fuzzy kernel clustering SVM is proposed to combat the multipath and shadowing effects. The first step of the proposed positioning algorithm is to use kernel function to map the traditional fingerprints sample data to high-dimensional feature space to generate fuzzy classes. The second step is to generate binary-class SVM of fuzzy class based on the relationship between classes and internal discrete information of each class. After that, we can use the binary fuzzy class SVM to dichotomize the classified fingerprints in the first step, and combine these dichotomous SVMs into a handstand classification binary tree. And thus, the proposed positioning algorithm achieves quick and accurate positioning. Experimental results show that the positioning accuracy and locating stability of proposed positioning algorithm are improved by 38.73% and 59.26%, respectively, compared with the traditional RSS fingerprints algorithm.

     

Efficient and photostable CsPbl2Br solar cells realized by adding PMMA

Organic-inorganic hybrid perovskite materials demonstrate promising applications in high-efficiency perovskite solar cells (PSCs) with a certified power conversion efficiency (PCE) of 25.5％ (https://www.nrel.gov/pv/cell-efficiency.html).However, intrinsically volatile and thermally unstable nature of the organic cations result in poor thermal stability of organic-inorganic hybrid perovskite materials, hampering the commercialization of organic-inorganic hybrid PSCs[1].All-inorganic CsPbl3-xBrx (x =0-3) perovskites have been attracting great attention in recent years because of their higher thermal stability[2].Among the reported CsPbl3-xBrx perovskites, CsPbl2Br bears a reasonable balance between bandgap and phase stability, thus becomes the most extensively studied material[3-15].Though there are many works aiming at achieving high-efficiency CsPbl2Br PSCs, improving the photostability of CsPbl2Br PSCs is another key for commercialization of all-inorganic PSCs.Intriguingly, it has been reported that CsPbl2Br is susceptible to make light-induced phase segregation, i.e.severe segregation of CsPbl2Br to low-bandgap I-rich and wide-bandgap Br-rich domains via ion diffusion, leading to obvious current-voltage hysteresis and decrease of stabilized power output (SPO)[16-20].Such a light-induced phase segregation can be suppressed by optimizing the interface between perovskite layer and charge-transport layer[18, 19].     

基于简单再生码的带宽感知的分布式存储节点修复优化

分布式存储系统为保证可靠性会采用一定存储冗余策略如多副本策略、纠删码策略.纠删码相对于副本具有存储开销小的优点,但节点修复网络开销大.针对修复网络开销优化,业界提出再生码与以简单再生码为代表的局部可修复码,显著降低了修复网络开销.然而,现有基于编码的分布式容错存储方案大都假设节点处于星型逻辑网络结构中,忽略了实际的物理网络拓扑结构和带宽信息.为实现拓扑感知的容错存储优化,相关研究在纠删码和再生码修复过程结合网络链路带宽能力,建立树型修复路径,进一步提高了修复效率.但由于编码和修复过程的差异性,上述工作并不适合于简单再生码修复.针对该问题,本文结合实际物理网络拓扑结构,将链路带宽能力引入到简单再生码的修复过程中,对带宽感知的简单再生码修复优化技术开展研究.论文建立了带宽感知节点修复时延模型,提出了基于最优瓶颈路径和最优修复树的并行修复树构建算法.并通过实验对所提算法性能进行了评估.实验结果表明,与星型修复方式相比,论文所提算法有效地降低了节点修复时延,提高了修复效率.     

基于假设检验的回归模型算法在脱靶量解算中的应用

在脱靶量处理中,准确选取弹道的拟合函数是计算脱靶参数的关键.本文首先利用假设检验的回归模型算法,合理选取模型并确定函数阶次,提高函数逼近程度,减小了经验选模的函数拟合误差.其次,通过运用双弹道的数据融合算法解算脱靶量参数,消除了传统算法在弹道参数衔接点的跳跃现象,并通过理论仿真和实测数据验证了算法的有效性.     

含二氮杂萘酮结构耐热胶粘剂的研究

研究了一种含二氮杂萘酮结构耐热型环氧固化剂，与低分子质量聚酰胺复合使用得到的环氧胶粘剂具有良好的耐热性，固化工艺为140℃／2h 180℃/3h,150℃有25MPa以上的拉伸剪切强度，以及极好的高温保持率，可达到100％。详细研究了表面处理方式和固化工艺对其在常温和150℃下拉伸剪切强度的影响。     

An XPS study of the sulfidation-regeneration cycle of a hydroprocessing catalyst

The formation of sulphates in an industrial Ni-W Hydroprocessing (HP) catalyst was investigated by X-ray Photoelectron Spectroscopy (XPS). A small fluidized bed test unit with on-line sampling device was constructed to simulate industrial sulfidation and oxyregeneration processes of HP catalysts. The results obtained show that the sulfates observed on the surface of sulfided catalysts are not formed during the sulfidation process. Two oxidation processes seem to be responsible for the formation of sulfates. One of the processes happens when the catalyst is exposed to air before it is properly cooled. The other is a slow conversion at ambient temperature. The two different processes might be associated to different sulfidic species formed during the sulfidation processes, with the sulfides in the bulk of catalyst particles being more easily oxidized than the ones on the external surface of the catalyst particles. The sulfate formed during the air oxidation of sulfided catalysts, as well as that after oxyregeneration is not aluminum sulfate but nickel sulfate in both cases. XPS results also indicate that oxygenates in the feedstock are not directly involved in the sulfate formation.     

提高PMMA塑料光纤芯材耐热性的方法

介绍了提高以聚甲基丙烯酸甲酯(PMM A)为芯材的塑料光纤的耐热性的方法。     

中水回用循环冷却水系统现场应用

天津滨海热电厂采用天津开发区中水作为循环冷却水系统的补充水，研究了适应天津滨海热电厂系统材质和工况条件的水处理药剂及其配套处理技术，并应用于现场运行。一年多的现场应用效果表明，中水回用于循环水系统的处理技术获得成功，并取得了明显的经济效益和社会效益。     

变频器在罗茨风机上的使用

由于工艺线的改造,我公司二台155kW罗茨风机由原来1 000t/d生产线入窑生料供料改为1 500t/d生产线生料库均化及入窑生料放库用,存在严重能力过剩.为了解决这一问题,我们在综合分析现有二台窑的生产工艺状况,从简化工艺、减少设备控制点、降低消耗等方面考虑,充分利用现有设备,取得很好效果。