AC发泡剂新工艺研究—Ⅲ电解氧化法

用钌钛金属阳极在含有Ｃｌ—和Ｂｒ－离子的酸性溶液中进行电解氧化联二脲制备偶氮二甲酰胺,获得产品得率为９３—９８％、纯度为９９．６％、电流效率为８８－９２％。母液可循环使用,基本不产生废液．     

数据驱动的公共卫生安全

Public health security incidents have emerged as one of the most pressing threats to human survival in the 21st century.This is particularly evident with the resurgence and re-emergence of infectious diseases,which pose a grave risk to global public health and socio-economic stability.In light of these challenges,the rapid development of big data analysis technology has paved the way for data-driven public health security,a crucial tool in our arsenal for infectious disease prevention,control,and informed decision-making.Data-driven public health security revolves around the collection,analysis,and utilization of extensive big data resources to prevent and control epidemics,which can significantly enhance our ability to safeguard public health.Among the various categories of public health security big data,genetic data stands out as a pivotal component.It provides valuable insights into microbial pathogen evolution and aids in the judgment of epidemic development from a molecular genetic evolutionary perspective.Research in this field strives to offer a scientific foundation for managing public health security by comprehensively analyzing large-scale genetic data,ultimately empowering us to respond more effectively to diverse public health challenges.Effective compliance management,intelligent analysis,and scientific application of pathogen genetic data are vital for constructing a robust framework for public health security.Firstly,in the context of current global outbreaks,pathogen genetic data has become a cornerstone for epidemic prevention and control.The urgent need to manage these data in compliance with standards is paramount.Secondly,intelligent analysis technologies play a pivotal role in extracting hidden information from pathogen genetic-related data,providing precise guidance for infectious disease prevention and control.Through the integration and analysis of pathogen genetic data,we can track pathogen evolution,predict new variants and transmission paths,issue timely warnings about transmission risks,and formulate effective prevention and control strategies.Finally,scientific application bridges the gap between theoretical knowledge and practical operations.Integrating pathogen genetic-related data with real-world scenarios allows us to develop more effective prevention and control measures,harness the potential of genetic data in public health security management,and elevate overall public health and security.This paper delves into the role of the China National Science Data Centers in the establishment of a comprehensive\"storage-management-use\"framework for genetic data in the realm of public health security.The objective is to enhance public awareness and understanding of genetic data-driven public health security.The China National Science Data Centers undertake the responsibility of collecting,integrating,and storing biomedical big data nationwide,facilitating big data mining applications.Their services encompass data exchange,integration and sharing,monitoring,and early warning platforms.These platforms ensure the timely,high-quality,and reliable availability of pathogenic microbial data and contribute to effective emergency responses,data usability improvement,spatiotemporal pathogenic genomic data tracking,and high-risk mutation and variant prediction using artificial intelligence.Taking inspiration from the experience of dealing with COVID-19,the databases and service platforms provided by the China National Genomics Data Center and China National Microbiology Data Center have played a pivotal role in real-time monitoring and the effective prevention and control of the pandemic.Furthermore,these resources serve as crucial technical reserves for addressing future emerging infectious public health crises.The development of these technologies and platforms has substantially bolstered China's capabilities in data-driven public health security,elevating its influence in global public health governance.     

长爪沙鼠性成熟前后生殖系统的发育情况

目的 深入探究长爪沙鼠性成熟过程中生殖系统的发育情况,为其性成熟的确切时间提供直接研究证据。方法 本研究选取 6 ~ 14 周龄长爪沙鼠共 150 只,按 6、8、10、12 和 14 周龄分为 5 组,每组雌雄各 15 只,称量体质量并采集卵巢、子宫、睾丸、附睾样本,测量各样本组织湿重并计算脏器指数;镜下观察卵巢外观形态;细胞计数仪检测精子数量;每组随机选取 6 个样本进行 HE 染色,观察卵巢、睾丸、附睾的组织发育情况。 结果 雌性沙鼠 10 周龄时卵巢湿重和卵巢指数均明显增加,且 10 ~ 14 周龄期间无明显变化,子宫湿重和子宫指数均呈阶段性变化;镜下观察外观,10 周龄、12 周龄、14 周龄组黄体发生率分别为 46. 7%、60%、73. 3%;组织切片显示,10 周龄起可见明显黄体。 雄性沙鼠在 6 ~ 10 周龄阶段睾丸湿重随周龄的增长而逐渐增加,10 周龄后无明显变化;睾丸指数在 8 及 12周龄时明显增加,14 周龄时明显减小;6 ~ 12 周龄阶段附睾湿重和附睾指数均随周龄的增长而逐渐增加,14 周龄时附睾湿重无明显变化,附睾指数明显减小。 细胞计数仪结果显示,6 周龄时精子数量为 0,10 周龄与 8 周龄相比,附睾内精子数量明显增加,10 ~ 14 周龄期间无明显变化。 组织切片显示,8 周龄起,睾丸和附睾内开始出现少量精子,10 周龄起可见大量精子。 结论 随着周龄的增长,雌性沙鼠卵巢在 10 周龄左右卵泡开始发育成熟并排出卵子,达到性成熟,具备繁殖能力。 雄性沙鼠 8 周龄左右开始产生精子,进入初情期,10 周龄左右睾丸发育稳定,精子达最大数量,达到性成熟,此后附睾继续发育,12 周龄左右发育稳定。     

有界噪声条件下基于集员滤波的扩展目标跟踪方法

现有概率框架下的扩展目标跟踪方法需要已知系统量测噪声统计特性,然而在实际过程中量测噪声大多为边界已知而统计特性未知的有界噪声,其难以利用概率方法对扩展目标运动状态与形态进行计算。针对有界噪声条件下的扩展目标跟踪问题,提出一种基于集员滤波的扩展目标跟踪方法,该方法通过UBB椭球集合对量测噪声进行表示,并采用集员滤波对运动状态集合参数进行计算。在对扩展目标形态估计过程中,结合凸包计算几何理论中的Graham scan算法,求解包含目标形态最大误差的最小边界矩阵,最后利用仿射变换和偏移超曲面计算椭球Minkowski差的边界参数,从而对目标形态矩阵进行更新。仿真结果表明,在有界噪声条件下,相比于传统概率框架下的贝叶斯滤波方法,文中所提出的方法对目标运动和扩展形态的跟踪精度更高。     

无网格法求解分段连续型延迟偏微分方程

考虑了一类分段连续型延迟偏微分方程.首先分析了方程的解析解,给出了级数形式的解.其次采用无网格法求解了该类方程的数值解.利用θ-加权有限差分法对方程的时间变量进行离散,并利用Multiquadric(MQ)径向基函数和配点法建立了全离散格式.采用傅里叶分析法给出了数值方法稳定的条件.通过数值算例给出了方法的误差及验证了方法的有效性.     

基于虚拟深度的聚焦型显微光场相机深度测量标定

针对聚焦型显微光场相机在内部光学参数未知的情况下,进行了基于虚拟深度的深度测量标定。首先基于高斯光学建立光场成像模型,推导出虚拟深度与实际深度间的函数关系。然后选择单一角点的标定板,在不同深度位置进行拍摄;该角点在多个宏像素中重复成像,相邻重复像点的间距随深度位置改变而变化;利用图像匹配的方法计算相邻重复像点的距离和虚拟深度值,并与实际深度一一对应进行曲线拟合。根据拟合结果,分析了不同深度位置下,该光场成像系统的深度测量分辨率。最后,通过拍摄已知倾角的倾斜棋盘格标定板,进行深度测量并分析测量误差,在主镜头工作距离靠近镜头方向2 mm(10倍景深)范围内,测量误差小于5.35%。     

岩石单结构面剪切变形渗透性演化规律

为了研究剪切作用下单裂隙渗透性的演化规律,在Comsol中采用Weierstrass随机分形函数来生成单裂隙,调整2个裂隙面的相对位移来模拟剪切作用,通过分析不同剪切位移条件下裂隙隙宽的变化以及不同流量下的非线性效应发生的界定范围,并绘制散点图与函数曲线拟合确定剪切过程影响裂隙渗透率的因素,给出定量关系。结果表明：未发生剪切时,隙宽的概率密度分布满足标准的高斯分布,而随着剪切过程的发生,隙宽的高斯分布被破坏,仅体现标准高斯分布的部分特征;发生剪切时,渗透率先有一个减小的过程,然后在一定范围内波动;当Re>9.6时,流体开始从线性向非线性发展。对岩石单结构面剪切变形过程中裂隙孔径变化对流体渗流特性的影响进行模拟,可为分析地质体中结构面变形对地热变化的影响提供参考。     

一个新的水稻幼苗黄叶突变体的遗传分析及其基因的初步定位

在60Coγ射线辐照的水稻突变体库中,发现了一个以粳稻品种日本晴为遗传背景的幼苗叶色黄化突变体syl11(seedling yellow leaf 11).与野生型相比,突变体幼苗第二和第三叶表现黄色,在其完全展开之前叶片自其顶端开始转绿,长到四叶期其叶色恢复正常;并且该突变体syl11幼苗黄色叶片光合色素含量明显下降.遗传分析表明,该突变体的遗传性状由1对隐性核基因控制.本研究以培矮64S/syl11的F2代突变型植株作为定位群体,应用微卫星(SSR)分子标记以及新发展的InDel分子标记,将基因syl11定位在水稻第11号染色体长臂上的RM26652和处于着丝粒附近的ID11974分子标记之间,其遗传距离分别为0.5 cM和0.7 cM.     

基于情感教育的大学生道德教育探析

从情感教育的视角入手,以道德教育的理论,分析了中国当代大学生情感教育的现状,探讨了大学生道德情感教育缺失的原因,提出了有针对性的建议。