Lower down both ohmic and cathode polarization resistances of solid oxide fuel cell via hydrothermal modified gadolinia doped ceria barrier layer

Hydrothermal reaction in Cerium and Gadolinium solution as an optimization method is developed and first reported for the densification of gadolinia doped ceria, the barrier layer between Zirconia electrolyte and (La,Sr)(Co,Fe)O_3-δ cathode. This method is based on the hydrothermal reaction for nano particles in-situly grown on porous surface, to improve barrier layer density, alongside the sintering of cathode at 1075 °C. As a result, the ohmic resistance is prominently decreased by ～16.4 % at 750 °C for electrolyte supported symmetrical cell. Whereas, the cathode polarization resistance is decreased by as much as a factor of ～3 from 0.3702 Ω·cm² to 0.1325 Ω·cm² at 750 °C and $p_{O_2}=0.21atm$. Furthermore, the anode supported cell exhibits higher open circuit voltage, smaller area specific resistance, elevated performance output and less degradation. And this modified barrier layer shows reduced Sr migration in 300 h operation at 750 °C. The hydrothermal reaction is demonstrated to prepare denser and sintering-active barrier layer with faster oxygen ion transfer and better interface connection, with large-scale application prospects and cost-competitiveness.     

Bioengineered magnetoferritin nanozymes for pathological identification of high-risk and ruptured atherosclerotic plaques in humans

Atherosclerotic plaque rupture results in thrombus formation and vessel occlusion, and is the leading cause of death worldwide. There is a pressing need to identify plaque vulnerability for the treatment of carotid and coronary artery diseases. Nanomaterials with enzyme-like properties have attracted significant interest by providing biological, diagnostic and prognostic information about the diseases. Here we showed that bioengineered magnetoferritin nanoparticles (M-HFn NPs) functionally mimic peroxidase enzyme and can intrinsically recognize plaque-infiltrated active macrophages, which drive atherosclerotic plaque progression and rupture and are significantly associated with the plaque vulnerability. The M-HFn nanozymes catalyze the oxidation of colorimetric substrates to give a color reaction that visualizes the recognized active macrophages for one-step pathological identification of plaque vulnerability. We examined 50 carotid endarterectomy specimens from patients with symptomatic carotid disease and demonstrated that the M-HFn nanozymes could distinguish active macrophage infiltration in ruptured and high-risk plaque tissues, and M-HFn staining displayed a significant correlation with plaque vulnerability (r = 0.89, P < 0.0001).

     

等离子体预处理对解淀粉芽胞杆菌生长和α-淀粉酶分泌的影响

本研究采用低真空室温射频等离子体对解淀粉芽胞杆菌CICC 10035进行预处理，通过改变放电功率、处理时间和工作气压等参数，筛选最佳工艺条件，并使用蛋白质组学技术，对差异蛋白质进行生物信息学分析，探讨等离子体预处理对菌体生长和产酶性能的影响。结果表明，等离子体预处理的最佳工艺条件为：放电功率120 W，处理时间15 s，工作气压135 Pa。在最佳条件下，发酵48 h后，α-淀粉酶酶活超过400 U/mL，与对照样相比提高约20%。蛋白组学分析表明，等离子体预处理对菌体的蛋白合成及代谢产生了较强的正效应，尤其在DNA修复和氨基酸合成上，一方面提高了菌体活性，延缓其衰亡过程；另一方面促进了α-淀粉酶在菌体内的合成和分泌。     

Research on product size and grinding dynamics of vibration mills

In order to improve vibration mills grinding effect and increase productive efficiency, prime factors of vibration mills were gained much attention. The purpose of this study is to reveal product size distribution and grinding dynamics of vibration mills by orthogonal experi-ments. The metallurgical refractory materials were used as research object. In order to explore the relationships between grinding effect and primary factors, lots of milling experiments were carried out. Based on the results, the conclusions can be summarized： as time runs, the size distri-bution shows exponential trend, and range becomes more and more narrow. Also the quantitative analysis result between grinding effect and primary factors was obtained by non-linear regres-sion： high frequency, high amplitude and low fill ratio can increase grinding speed.     

纳米粉体粒度特性表征方法讨论

实验中采用不同的方法对四种ZrO2纳米粉体的颗粒特性进行了表征。对颗粒呈现球形、不发生硬团聚的微小粒子，例如YSZ—KD试样，一次颗粒粒度为10～15nm，比表面为64．2m^2／g，采用XRD获得的微晶粒子尺寸与TEM和BET方法获得的颗粒尺寸相一致。由于比表面高，颗粒之间容易发生静电力、范德华力和液桥力的作用而软团聚在一起，其团聚系数较大为62．5，粒度分布宽度为14．58。TEM和BET与XRD方法获得的颗粒尺寸出现偏差，说明YSZ—HW1、YSZ—TH试样中出现了基元为2～3的多晶颗粒，多晶颗粒存在使得颗粒体偏离球形。团聚系数为25．71，粒度分布宽度为18．94的YSZ—HW1试样中仍存在较多的软团聚体，团聚系数为6．89，粒度分布宽度为8．91的YSZ—TH试样中软团聚状况明显较少。YSZ—HW2试样中TEM和BET与XRD方法获得的颗粒尺寸出现很大偏差，说明其中存在较多的硬团聚体，硬团聚体使得颗粒呈现不规则外形，其比表面小，活性低，表现为团聚系数小，粒度分布窄。     

煤矿“一通三防”管理信息系统构架研究

基于C/S模式的煤矿安全管理信息系统,充分利用了传统C/S模式的优势与特点,具有便捷省时的输入方式及其他业务处理功能,图形化数据查询结果等辅助数据管理功能和系统管理功能,可为煤矿领导作出安全决策提供技术支持。     

矿用隔爆型电磁启动器用电子保护器选型

对目前煤矿井下使用的3种电动机综合保护装置进行了比较，并提出了最佳选型。     

可伸缩悬臂式装煤机的研制

可伸缩悬臂式装煤机适用于仓房开采条件，主要可以提高仓房开采的资源回收率，减轻工人的劳动强度，增加现场作业的安全可靠性。     

利用光聚合反应制作表面平整的聚合物光栅

提出利用紫外光聚合反应来制作聚合物光栅的方法．实验发现,光栅的表面起伏深度很小,约为12.4～0.7nm;折射率调制较大,达到0.010左右．这种方法在低阶分布反馈聚合物激光器的制作中具有很好的应用前景．     

Further study on the flexural behaviour of concrete-filled steel tubes

This paper is a further study on the flexural behaviour of concrete-filled steel tubes based on the former work presented by Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37]. A total of 36 composite beam specimens filled with self-consolidating concrete (SCC) were tested. The main parameters varied in the tests are: (1) sectional types (circular and square); (2) steel yielding strength (from 235 to 282 MPa); (3) the ratio of tube diameter (or width) to wall thickness, D/t (from 47 to 105), and (4) the ratio of shear span to depth (from 1.25 to 6). Comparisons are made with predicted beam capacities using the existing methods, such as AIJ-1997 [Architectural Institute of Japan (AIJ). Recommendations for design and construction of concrete filled steel tubular structures. 1997], AISC-LRFD-1999 [AISC. Load and resistance factor design specification for structural steel buildings. Chicago: American Institute of Steel Construction, Inc.; 1999], BS5400-1979 [British Standard Institute: BS5400, Part 5, Concrete and composite bridges. 1979], EC4-1994 [Eurocode 4. Design of composite steel and concrete structures, Part 1.1: General rules and rules for buildings (together with United Kingdom National Application Document). DD ENV 1994-1-1:1994. London W1A2BS: British Standards Institution; 1994] and the method proposed by Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37].Applied calculation formulae of moment versus curvature curves and the flexural stiffness of concrete-filled steel tubular (CFST) beams are presented, based on the mechanics model of Han [Han LH. Flexural behaviour of concrete-filled steel tubes. Journal of Constructional Steel Research 2004;60(2):313-37]. Comparisons are made with predicted beam flexural stiffness using different methods, such as AIJ-1997, AISC-LRFD-1999, BS5400-1979, EC4-1994 and the method proposed in this paper. Comparisons are also made between the simplified model and the mechanics model, and generally good agreement is achieved.