Fabrication of a Hierarchical Ni(OH)2@Ni3S2/Ni Foam Electrode from a Prussian Blue Analogue-Based Composite with Enhanced Electrochemical Capacitive and Electrocatalytic Properties

Developing high-efficiency, cost-effective, and durable electrodes is significant for electrochemical capacitors and electrocatalysis. Herein, a 3D bifunctional electrode consisting of nickel hydroxide nanosheets@nickel sulfide nanocubes arrays on Ni foam (Ni(OH)₂@Ni₃S₂/NF) obtained from a Prussian blue analogue-based precursor is reported. The 3D higher-order porous structure and synergistic effect of different compositions endow the electrode with large specific surface area, facile ion/electron transport path, and improved conductivity. As a result, the Ni(OH)₂@Ni₃S₂/NF electrode exhibits a high specific capacity of 211 mA h g⁻¹ at a current density of 1 A g⁻¹ and 73 % capacity retention after 5000 cycles at 5 A g⁻¹. Moreover, the Ni(OH)₂@Ni₃S₂/NF electrode has superior electrocatalytic activity for the hydrogen evolution reaction with low overpotentials of 140 and 210 mV at current densities of 10 and 100 mA cm⁻², respectively. The synthetic strategy for the unique higher-order porous structure can be extended to fabricate other composite materials for energy storage and conversion.     

基于大学生物理学术竞赛的新模式本科毕业设计探索与实践

本科毕业设计是高校人才培养中关键的教学环节,是“新工科”背景下和“双一流”建设中一项基础而又至关重要的工作.基于大学生物理学术竞赛的思想理念和特点优势,结合本科毕业设计的教学要求,详细探讨了新模式毕业设计中的分流选题、教师指导、答辩模式、成绩评定、过程管理等环节的实践措施,为提升大学的本科毕业设计,乃至本科人才培养质量提供新的思路.     

转子叶尖引射式射流的数值研究

转子叶尖射流能够有效地提高压气机的稳定工作裕度, 但是现有的各种射流器结构复杂, 并使发动机的重量增加. 研究目的在于探索一种新型的射流方式, 以方便在压气机中的实现,并且不增加发动机的重量. 采用对转子叶尖前缘位置机匣进行局部修型的方法, 提高了转子叶尖前缘附近流场的轴向速度, 从而产生类似转子叶尖射流的效果. 在Rotor37上的数值分析发现, 该方法能够提高转子的失速裕度约6.7%, 并能使转子的效率与压比有较小的提升. 对比不同机匣修型方案发现, 修型位置对压气机裕度的影响最为明显. 对转子叶尖流场的分析表明, 该方法能够提高转子叶尖前缘的轴向速度, 并将叶尖泄露涡向下游推移, 减小了转子叶尖的流动堵塞, 从而拓宽了转子的失速裕度.      

一类非线性含时滞阻尼项双曲型方程解的振动性质

本文讨论一类含时滞阻尼项的非线性双曲型方程解的振动性质,所得判别振动的充分条件从理论上揭示了这类方程与普通双曲型方程质的差异,且应用十分便利;同时指明了振动由时滞量引起这一重要结论。     

Prolonged hypotensive effect of human tissue kallikrein gene delivery and recombinant enzyme administration in spontaneous hypertension rats

To evaluate the feasibility of treating hypertension by human tissue kallikrein gene (KLK1) delivery and by enzyme (rK1) administration, two recombinant vectors expressing KLK1 cDNA were constructed for gene delivery (pcDNA-KLK1) and recombinant enzyme preparation (pOV-KLK1). Expression of the pcDNA-KLK1 vector in COS-1 cells was confirmed by immunofluorescence and in spontaneous hypertension rats (SHR) by enzymatic detection. Following intramuscular or intravenous injection with the pcDNA-KLK1 vector, systolic pressure of SHR was significantly decreased, which lasted for 20 d to two months depending on dose, route and/or time of injection. Egg white containing recombinant hK1 was prepared by injection of egg-laying hens with the oviduct-specific expression vector pOV-KLK1 and administered into SHR via oral gavage. Following administration, systolic pressure of the SHR was decreased to that of normal rats, which lasted for 3-5 d depending on the dosage used. These data suggest that both hKLK1 gene delivery and recombinant enzyme administration can be used as alternative strategies for treating human hypertension.     

Computational models for the helix tilt angle

The concept of hydrophobic imbalance and that of hydrophobic and hydrophilic centers are used along with side chain models in the computation of helix orientation and tilt angle in or near a membrane. Rotamer statistics are used to infer typical side chain positions and chain length for each amino acid, and the results are used in fast computation of helix orientation. Sliding windows are used to compute local tilt angles on long alpha-helices that defy idealized modeling and generate tilt angle profiles. Seven different procedures based on different formulas and hydrophobicity scales are used for comparison. These procedures generated very similar tilt angle profiles. These profiles provide insights into helix deformation, membrane destabilization, and similarity and differences between membrane proteins.     

Rapid hemostasis and excellent antibacterial cerium-containing mesoporous bioactive glass/chitosan composite sponge for hemostatic material

Rapid and effective hemostasis is key to controlling bleeding and reducing mortality. Here, a composite hemostatic sponge (Ce-MBG/CHT) of cerium-containing mesoporous bioactive glass (Ce-MBG) and chitosan (CHT) was prepared by a freeze-drying technique and compared with the commercially available gelatin sponge (GS), to further evaluate the hemostatic performance of composite sponge materials. The results indicate that the pore structure, porosity, and water absorption of the sponge improved following the addition of Ce-MBG. Whole blood coagulation studies suggested that Ce-MBG/CHT has superior hemostatic properties to GS and validated in vitro thrombosis, platelet adhesion and blood compatibility. In vitro coagulation studies showed that factor XII was activated by the addition of Ce-MBG, inducing the intrinsic coagulation pathway. Furthermore, we evaluated the cytocompatibility of samples after contact with L929 cells for 24, 48, and 72 h via the cytotoxicity test. Compared with GS, 4Ce-MBG/CHT was more efficient against E. coli and S. aureus. All these results indicate that Ce-MBG/CHT sponges are likely useful for rapid hemostasis.     

Rapid promoting thrombus formation and fibrin cross-linked Bi-doped mesoporous bioglass for hemostatic agent

Despite decades of development of biomaterials, hemorrhage remains a primary cause of death in surgeries and accidents. Effective hemostatic agents that induce hemostasis and rapid coagulation are needed by surgeons and in daily life. Here, we report on the application of hemostatic agents by studying mesoporous bioglass (MBG) doped with bismuth oxide via a two-step acid-catalyzed self-assembly (TSACSA) process. The results show that all the samples have an ordered mesoporous structure and a large surface area, especially MBG doped with 2 mol% Bi₂O₃ has the highest specific surface area (704.06 m²/g). MBG doped with different proportions of Bi accelerated the intrinsic coagulation pathway and was not found to exhibit severe erythrocyte cytotoxicity. It is worth noting that MBG added with 1 and 2 mol% Bi₂O₃ had higher thrombus formation, fibrin polymerization rates, and platelet adhesion; however, higher content of Bi₂O₃ (3 mol%) may affect the consequence of coagulation. These results of our investigation suggest that MBG doped with a low range of Bi is a potential hemostatic biomaterial for clinical applications.     

Oscillation of Nonlinear Hyperbolic Differential Equations with Impulses

We study oscillatory properties of solutions of nonlinear impulsive hyperbolic differential equations and find new necessary and sufficient conditions for the existence of oscillations.__________Published in Neliniini Kolyvannya, Vol. 7, No. 4, pp. 439–445, October–December, 2004.     

三维结构在循环加载条件下弹塑性分区边界元法及其应用

本文发展了一种三维结构在单调和循环加载条件下的弹塑性分析的分区边界元法并完成了相应软件的开发。采用了改进的双面理论模拟循环加载条件下的材料性质,引进了有效的奇异积分数值处理方法和推广的返回向量法(作为双面本构理论的近似积分方法,最后,运用该软件对常用的工程构件——吊钩进行了应力应变分析,并与相应的实验结果作了较为详细的比较分析。