Microstructure and coloring mechanism of iron spots on bluish white porcelain from Jingdezhen of the Song Dynasty

Jingdezhen is famous for its bluish white (Qingbai) porcelains of the Song Dynasty, and those decorated with iron spots are distinctive among them. Herein, iron spots on a bluish white porcelain were investigated using a series of microscopic and spectroscopic characterizations. We found the decreasing iron content from more than 8 wt% to about 2 wt% during the glaze color transition from rusty to brown and finally into green, which built a connection on the coloring mechanism of iron-rich crystallized glaze and celadon glaze. We identified the rare ε-Fe₂O₃, a promising magnetic material, in both the dark brown crystals and the triangular crystals in the rusty area, which is its first discovery among bluish white porcelains. Based on these findings, we discussed the coloring mechanism of iron-spot decoration along with the physical form of the iron oxide crystals, indicating the partially reducing atmosphere during firing process.     

基于乙酰胆碱酯酶和氧化应激研究海胆酮对阿尔茨海默症的作用机制

海胆酮是一种酮式类胡萝卜素，主要从海胆及藻类等海洋生物中提取。本文研究海胆酮对乙酰胆碱酯酶（acetylcholinesterase，AChE）的抑制作用，应用酶动力学、荧光光谱、圆二色光谱和分子对接技术研究海胆酮对AChE的抑制机理，并用淀粉样β蛋白片段25～35（amyloid beta-peptide 25-35，Aβ25-35）诱导大鼠肾上腺嗜铬细胞瘤细胞（PC12细胞）建立阿尔茨海默症（Alzheimer’s disease，AD）模型，研究海胆酮对AD细胞模型氧化应激损伤的作用。结果表明，海胆酮有很强的AChE抑制活性，其半抑制质量浓度为（16.29±0.97）μg/mL，抑制常数Ki为3.82 μg/mL，表现为竞争性抑制；海胆酮可诱导AChE二级结构改变，更容易与AChE活性中心氨基酸Ser200、His440、Trp84和Tyr121结合，阻碍底物碘代硫代乙酰胆碱（acetylthiocholine iodide，ATCI）与酶结合，从而引起酶活力降低。海胆酮能有效抑制Aβ25-35诱导PC12细胞的AChE活力，降低丙二醛含量，增加超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活力，减轻Aβ25-35诱导的PC12细胞氧化应激损伤。本研究基于AChE和氧化应激阐明了海胆酮对AD的潜在作用机制，为海胆酮在功能食品、生物医药等领域的应用提供了数据支持和理论根据。     

基于6Li+CdTe的新型中子探测器的优化设计研究

面对~3He气体资源严重短缺的国际形势,2018年基于~6Li+CdTe新型中子探测器方案被提了出来,其具备热中子探测效率高、γ灵敏度低及可与~3He气体中子探测器相比拟的特点,有很好的应用前景。本文分析~6Li+CdTe中子探测器的结构和工作原理,采用MCNP6软件对~6Li+CdTe中子探测器进行物理建模并且对其物理性能、结构参数、中子慢化体设计等进行模拟计算,并就该探测器在特殊核材料监测系统中的应用开展了探索研究。结果显示:CdTe吸收层的最佳厚度为10μm;当6层~6Li+CdTe的中子探测单元叠加时,~6Li转化层的最佳厚度为60μm,此时热中子探测效率超过50%;探测系统的尺寸达到4 m×32 cm时,可以满足特殊核物质监测的要求。整个模拟研究获得了探测器最佳工作参数以及辐射监测系统设计方案,对特殊核材料在线中子监测装置的实验研究具有指导意义。     

内热型超声雾化溶液再生系统最优内热量的研究

基于质量守恒、能量守恒定律，建立了内热型超声雾化溶液再生系统（IH-UARS）的再生性能预测模型并进行了充分的实验验证，通过研究不同内热量下IH-UARS的再生性能及其变化规律，寻求系统所需的最佳内热量并明确其可能的影响因素。结果表明：IH-UARS系统存在最优的内热量范围，使其再生系统性能最佳；所需最优内热量随着再生溶液流量增大呈显著的对数增长，但受空气流量的影响较弱；在该研究中的标准工况下，IH-UARS所需最优内热量约为275~350 W。此外研究发现：内热量的增长有益于促进初始浓度较高的溶液进一步浓缩再生，如当IH-UARS中内热量增至800 W时，其初始浓度为36%的溶液比24%的溶液浓度增量指标改善幅度高37%。研究所得结果可对提高溶液再生性能及经济性提供积极参考。     

Fabrication of hierarchical PANI@W-type barium hexaferrite composites for highly efficient microwave absorption

Hexagonal barium ferries is a promising and efficient microwave (MW) absorbing material, but the low dielectric loss and poor conductivity have limited their extensive applications. In this work, a simple tactic of coating conductive polymer PANI on hexaferrite BaCo₂Fe₁₆O₂₇ is presented, wherein the dielectric properties are customized, and more significantly, the electromagnetic loss is greatly enhanced. As displayed from structural characterizations, PANI were coated equably on the surface of hexaferrite grains by an in-situ polymerization process. The outcomes exhibit the as-prepared PANI@hexaferrite composite has remarkable electromagnetic wave absorption capacity. When the thickness is 6.0 mm, the minimal RL of ?40.4 dB was achieved at 2.9 GHz. The effective absorption bandwidth (RL < ?20 dB) of 0.65 GHz, 0.53 GHz, 0.65 GHz, 0.52 GHz, 0.46 GHz and 0.39 GHz was achieved separately when the thickness ranges from 4 to 9 mm. The highly efficient MW absorbing performance of PANI@hexaferrite composite were the consequence of multiple loss mechanisms and perfect impedance matching. It is demonstrated that the PANI@hexaferrite composite with excellent MW absorption performance is expected to be potential MW absorbers for extensive applications.     

Microenvironment and related genes predict outcomes of patients with cervical cancer: evidence from TCGA and bioinformatic analysis

Cervical cancer (CESC) is one of the most common cancers and affects the female genital tract. Consistent HPV infection status has been determined to be a vital cause of tumorigenesis. HPV infection may induce changes to the immune system and limit the host’s immune response. Immunotherapy is therefore essential to improving the overall survival of both locally advanced and recurrent CESC patients. Using 304 relevant samples from TCGA, we assessed immune cell function in CESC patients to better understand the status of both tumor micro-environment cells and immune cells in CESC. Functional enrichment analysis, pathway enrichment analysis, and PPI network construction were performed to explore the differentially expressed genes (DEGs). The analysis identified 425 DEGs, which included 295 up-regulated genes and 130 down-regulated genes. We established that upregulation of CCL5 was correlated with significantly better survival, meaning that CCL5 expression could serve as a novel prognostic biomarker for CESC patients. We further focused on CCL5 as a hub gene in CESC, as it had significant correlations with increased numbers of several types of immune cells. Cell-type fractions of M1 macrophages were significantly higher in the high-immune-scores group, which was associated with better overall survival. Finally, we concluded that CCL5 is a promising prognostic biomarker for CESC, as well as a novel chemotherapeutic target.     

喷雾干燥法制备材料论文的指导方案

喷雾干燥技术的突出特点是将液态物料瞬时干燥成固体粉末或者颗粒。我们课题组在指导本科生毕业论文中采用了喷雾干燥法制备碳包覆铌酸钛材料的实验,在实验过程中我们发现了一些问题,如喷雾干燥机需要适当预热、喷头容易堵赛和收集原料不干等问题。我们就以上问题进提出了相应的对策,这加深了本科生对喷雾干燥实验的体会和认识,培养了学生在独自实验时面对问题解决问题的能力。     

大港孔店油田本源微生物代谢产物监测分析

应用放射性同位素示踪剂技术研究了大港孔店北二断块水动力学关系,结果表明该区块注水井和采油井之间具有紧密的水动力学连通关系。在本源微生物驱油试验阶段,对试验区微生物及其代谢物在地层中的分布状况进行了3年连续监测,表明本源菌激活期间菌数增加102~105倍,原油部分氧化,使得低分子脂肪酸(乙酸盐,甲酸盐,丁酸盐等)含量约增加10~100倍,碳酸氢盐从0·4~0·6g/L增加到0·7~1·8g/L,产生的生物表面活性剂使地层水平均表面张力降低至48~33·3mN/m,地层水相对石蜡平均界面张力降至25~13·7mN/m,产生的生物多糖代谢物使地层水平均粘度增至0·76mPa·s,最高达0·83mPa·s。这些变化改变了油层物理化学和生态环境,改善了原油流动性,尤其是水动力学连通关系最好的井地层水组成的改变和增油降水效果最为明显。试验区监测结果表明,微生物及代谢物随注入水主流动方向运移,生物表面活性剂和低分子脂肪酸及生物聚合物的作用是提高原油采收率的主要机理。     

基于UC/OS-Ⅱ的网络控制系统通讯接口设计

基于UC／OS—Ⅱ实时操作系统的网络控制系统，通过以太网将服务器和各地控制器联结，可控制多个电机协调运动．服务器采用工业级计算机，客户端(控制器)采用集成网卡接口的嵌入式系统，通过交换机进行数据交换．系统根据IP地址将命令送给各控制器，同时将客户端状态返回，并通过检验校验字符的方式减少联网过程的握手次数．其通讯的最基本函数用标准C语言编写，生成静态库文件，可直接通过工程方式使用．其通讯接口包括联网初始化、服务器和客户端网络联接、以及控制、并常处理和维护等程序。     

热镀锌板(卷)工程设计中的环境保护问题

对热镀锌板(卷)的生产工艺、主要生产设备进行了简要介绍，并就其污染源(工序)、生产过程中产生的污染物及其控制措施进行了评述，同时就设计和生产中宜注意的几个环保问题进行了分析。