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Chinese Chemical Letters 2006年第6期17卷 714-716页

作者： Shu Tao ma hong xiang LOU School of Pharmacy Shandong University Jinan 250012

Novel ethyl 7-chloro-6-fluoro-l-methyl-4-oxo-1, 4-dihydro-[1, 3]thiazeto[3, 2-a]quino- line-3-carboxylate 2 was prepared from 3-chloro-4-fluoroaniline in eight steps. It can be used as a new intermediate for the synth... 详细信息

关键词： Synthesis tricyclic fluoroquinolone.

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基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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基于分子束外延技术可控制备Ga原子团簇的研究

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原子与分子物理学报 2025年第3期42卷 77-84页

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结... 详细信息

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结果表明,Ga源温度的升高导致Ga的蒸发量增加,进而沉积在Si衬底表面的Ga原子增多,Ga原子自组装成团簇,最终表现为Ga原子团簇的高度升高.第二组对照实验分别在3 s、6 s、10 s、40 s、50 s、60 s的沉积时长下制备Ga原子团簇.实验结果表明,沉积时长增加导致团簇的高度逐渐增加,主要由新吸附原子和竞争效应驱动.第三组对照实验分别在0 s、60 s、300 s的退火时长下制备Ga原子团簇.实验结果表明,退火时长的增加导致团簇的高度下降和团簇内的原子重新排列和分布有关.第四组对照实验分别在420℃、500℃的退火温度下制备Ga原子团簇.实验结果表明,升温至500℃退火会促进Ga原子团簇呈现有序排列,是表面原子的热运动和Ga原子团簇与Si(100)的晶格匹配度的共同作用的结果.

关键词： MBE Ga原子团簇 Ga源温度沉积时长退火时长

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Gut microbiota in cancer initiation,development and therapy

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Science China Life Sciences 2025年

作者： Ruyi Zhang xiang Zhang Harry Cheuk Hay Lau Jun Yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong Kong

Cancer has long been associated with genetic and environmental factors,but recent studies reveal the important role of gut microbiota in its initiation and *** 13%of cancers are linked to infectious agents,highlighting the need to identify the specific microorganisms *** microbiota can either promote or inhibit cancer growth by influencing oncogenic signaling pathways and altering immune *** can lead to cancer,while certain probiotics and their metabolites may help reestablish microecological balance and improve anti-tumor immune *** into targeted approaches that enhance therapy with probiotics is ***,the effects of probiotics in humans are complex and not yet fully ***,methods to counteract harmful bacteria are still in *** clinical trials also indicate that modifying gut microbiota may help manage side effects of cancer *** research is crucial to understand better how gut microbiota can be used to improve cancer prevention and treatment outcomes.

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Threshold dynamics of a multi-group SEAR alcoholism model with public health education

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International Journal of Biomathematics 2019年第3期12卷 39-62页

作者： Shuang-hong ma Hai-Feng Huo hong xiang College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 P. R. China Institute of Applied mathematics Lanzhou University of Technology Lanzhou 730050 P. R. China

In this paper, we investigate the threshold dynamics of a multi-group SEAR alcoholism epidemic model with public health education. The multi-group model allows us to describe interactions both within-group and inter-group separately. We prove that the basic reproduction number R0 plays the role of a threshold for the long-time behavior of the model. The alcohol-free equilibrium P0 of the model is globally asymptotically stable if R0≤1,while the alcohol-present equilibrium P* exists uniquely and is globally asymptotically stable if R0>*** the proofs of main results, we use the classical method of Lyapunov functions and apply subtle grouping technique in estimating the derivatives of Lyapunov functions guided by graph theory. Our results expand the previous results which have been obtained in single-group models. Sensitivity analysis and numerical simulations are also performed to illustrate our results.

关键词： Multi-group model alcoholism graph-theoretic approach global stability

学时缩减背景下动物学及其实验课程教学改进尝试

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教育教学论坛 2017年第2期 265-266页

作者：杨晓菁顾延生李继红马相如中国地质大学(武汉)环境学院生物系湖北武汉430074

动物学是一门生物科学专业重要的基础课程。在普遍缩减学时的大环境下,为提高教学质量,同时培养学生的自主学习能力和专业综合素养,在动物学理论及其实验课的教学内容、教学方法等方面分别进行了改进尝试。

关键词：动物学学时缩减教学改进

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Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin ma Chuan-Zeng Wang Wei Zhang hong-Tao Lin Jin Zhou Shu-Ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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Stable copper boron–imidazolate cage as Cu-riched enzyme for highly efficient electrocatalytic CO2 reduction to ethylene

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Science China Chemistry 2025年

作者： Jun-Qiang Chen Qiao-hong Li Qin-Long hong Ping Shao Hai-Xia Zhang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6L4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6L4]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 ma cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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葛根汤颗粒喷雾干燥工艺条件试验研究

山东大学学报（医学版） 2003年第6期41卷 706-707页

作者：季梅娄红祥马斌任冬梅山东大学药学院

目的:优选葛根汤颗粒喷雾干燥的最佳工艺条件。方法:应用正交设计法,以每小时药粉产率及有效成分含量为考察指标,对影响葛根汤喷雾干燥过程的因素进行考察。结果:正交试验法设计的三个因素中,浸膏的相对密度影响显著,入塔风温影响较显... 详细信息

目的:优选葛根汤颗粒喷雾干燥的最佳工艺条件。方法:应用正交设计法,以每小时药粉产率及有效成分含量为考察指标,对影响葛根汤喷雾干燥过程的因素进行考察。结果:正交试验法设计的三个因素中,浸膏的相对密度影响显著,入塔风温影响较显著。结论:颗粒最佳工艺条件为:入塔风温:170℃,气流量:700L/h,浸膏相对密度:1.22,在此条件下,葛根汤颗粒有效成分中葛根素及芍药苷的含量明显高于原湿法制粒制剂。

关键词：葛根汤颗粒喷雾干燥葛根素芍药苷

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Generating prototypical residential building geometry models using a new hybrid approach

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Building Simulation 2022年第1期15卷 17-28页

作者： Yuanli ma Wu Deng Jing Xie Tim Heath Yeyu xiang Yuanda hong Department of Architecture and Built Environment University of Nottingham Ningbo ChinaNingbo 315100China Key Laboratory of Carbonaceous Wastes Processing and Process Intensification Research of Zhejiang Province University of Nottingham Ningbo ChinaNingbo 315100China Departmentof Architecture and Built Environment University of NottinghamNottinghamUK

Building prototyping has regularly been used in building performance analyses with statistically feasible *** novelty of this research involves a new hybrid approach combining stratified sampling and k-means clustering to establish building geometry *** research focuses on residential buildings in Ningbo,*** small residential districts(SRDs)containing 367 residential buildings were systemically selected for survey and data *** stratified sampling used building construction year as the main parameter to generate *** numbers,shape coefficients,floor areas,and window-to-wall ratios were used as the four observations for k-means *** on this new approach,nine building geometry prototypes were identified and *** statistically representative prototypes provide building geometrical information and characteristic-based evaluations for subsequent building performance analysis.

关键词： building prototyping geometry models new hybrid approach Ningbo China