Asymptotics of Smoothed Wasserstein Distances

Potential Analysis - We investigate contraction of the Wasserstein distances on $\mathbb {R}^{d}$ under Gaussian smoothing. It is well known that the heat semigroup is exponentially contractive...     

80.5 MeV/u碳离子诱发铜靶的放射性剩余产物测量

高能重带电粒子能直接穿透靶原子核外电子层,与原子核发生直接碰撞,发生散裂反应,产生一系列具有放射性的剩余产物核.重带电粒子诱发靶材放射性剩余核与辐射防护和人员安全有着密切联系,当前,大部分剩余核产额主要依靠蒙特卡罗粒子输运程序进行模拟计算,其准确程度亟需通过实验测量进行准确评估.本文利用能量为80.5 MeV/u的(12)^C⁶⁺粒子对薄铜靶开展了辐照实验与伽玛射线测量,结合伽玛谱学分析方法,得出了辐照产生的18种放射性剩余产物的初始活度和产生截面值,并与PHITS模拟结果进行对比.结果表明,PHITS模拟程序对放射性剩余核种类的估计具有较高可靠性,在其绝对产额方面,与实验测量仍具有较大偏差.     

Preparation and characterization of ultrasensitive and specific polyclonal antiserum against ciprofloxacin based on cationized bovine serum albumin

An ultrasensitive polyclonal antiserum against ciprofloxacin (CPFX) was developed by introducing cationized bovine serum albumin (BSA) as the carrier. Conjugates used as immunogens were synthesized using CPFX coupled to BSA cationized with ethylenediamine and hexamethylenediamine, namely CPFX-eBSA and CPFX-hBSA. The results showed that the antisera immunized with CPFX-hBSA exhibit an improved sensitivity and specificity compared with those immunized with CPFX-eBSA. Under the conditions of optimal heterologous enzyme-linked immunosorbent assay, the optimal antiserum yielded an IC₅₀ of 0.097 ng mL^?1, which proves it to be more sensitive than any CPFX antibody. Cross-reactivities with norfloxacin, enrofloxacin, and ofloxacin were < 3.0 %. No cross-reactivities with penicillin and gentamicin were found. The limit of detection was 0.01 ng mL^?1, which is far below the maximum residue level established by the EU regulation, suggesting the great potential of the presented antiserum for quantitative assays of CPFX in samples.     

Alkyne–azide cycloaddition catalyzed by a dinuclear copper(I) complex

A novel dinuclear copper complex Cu^I₂(pip)₂ was used as a catalyst for alkyne–azide cycloaddition (CuAAC) reaction. High yields (95–99%) were obtained for various substrates at a low loading of 0.2 mol %. The unique structure, high stability of the dinuclear structure in solution, and easy preparation make this complex not only a high-efficiency catalyst but also a model for understanding the mechanism of the CuAAC reaction.     

Four New Gallate Derivatives from Wine-Processed Corni Fructus and Their Anti-Inflammatory Activities

Four new gallate derivatives—ornusgallate A, ent-cornusgallate A, cornusgallate B and C (1a, 1b, 2, 3)—were isolated from the wine-processed fruit of Cornus officinalis. Among them, 1a and 1b are new natural compounds with novel skeletons. Their chemical structures were elucidated by comprehensive spectroscopy methods including NMR, IR, HRESIMS, UV, ECD spectra and single-crystal X-ray diffraction analysis. The in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. As the result, all compounds exhibited anti-inflammatory activities at attested concentrations. Among the tested compounds, compound 2 exhibited the strongest anti- inflammatory activity.     

泡沫镍负载Fe2O3@Ni3S2纳米线网状结构电极的制备及其电催化析氧性能

通过两步水热法制备泡沫镍(NF)负载Fe_2O_3纳米粒子@Ni_3S_2纳米线网状结构电极(Fe_2O_3@Ni_3S_2/NF)。运用X射线衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、N_2吸附-脱附测试等方法对电极材料的物相和微观结构特征等进行了表征。水热条件下原位表面化学刻蚀生成的Ni_3S_2纳米线与三维多孔NF基体间拥有强结合力和低界面电阻,Fe_2O_3粒子均匀分布在纳米线的表面。在1 mol·L~(-1)的KOH溶液中,运用线性扫描伏安测试(LSV)、计时电位法、电化学交流阻抗测试(EIS)等对电极的电催化析氧(OER)性能进行了测试。结果表明:在100 mA·cm~(-2)的超高电流密度下,Fe_2O_3@Ni_3S_2/NF电极的OER过电势仅为223 mV,比Ni_3S_2/NF材料的过电势降低了285 mV;经过10 h计时电位测试,性能保持率高达80%。     

Cp2ZrCl2-catalyzed synthesis of 2-aminovinyl benzimidazoles under microwave conditions

A microwave-assisted general method for the synthesis of 2-aminovinyl benzimidazoles has been developed.Treatment of the 1,2-phenylenediamines and N-arylated/N,N-dialkylated 3-aminoacroleins with bis(cyclopentadienyl)zirconium(IV) dichloride(Cp2Zr Cl2) as the catalyst under microwave irradiation for 3–5 min followed by in situ Mn O2 oxidation afforded thirteen 2-aminovinyl benzimidazoles in good yields.     

低接触电阻率Ni/Ag/Ti/Au反射镜电极的研究

研究了Ag的厚度、退火时间、沉积温度对于Ni/Ag/Ti/Au电极的反射率及与p-GaN欧姆接触性能的影响. 利用分光光度计测量反射率, 采用圆形传输线模型计算比接触电阻率. 结果表明: 随着Ag厚度的增加, Ni/Ag/Ti/Au电极的反射率逐渐增大; 在氧气氛围中, 随着退火时间从1 min增至10 min, 300 ℃退火时, 比接触电阻率持续下降, 而对于400-600 ℃退火, 比接触电阻率先减小后增大; 在300和400 ℃氧气中进行1-10 min 的退火后, Ni/Ag/Ti/Au的反射率变化较小, 退火温度高于400 ℃时, 随着退火时间的增加, 反射率急剧下降; 在400 ℃氧气中3 min退火后, 比接触电阻率可以达到3.6×10^-3 Ω·cm². 此外, 适当提高沉积温度可以增加Ni/Ag/Ti/Au的反射率并降低比接触电阻率, 沉积温度为120 ℃条件下的Ni/Ag/Ti/Au电极在450 nm处反射率达到90.1%, 比接触电阻率为6.4×10^-3 Ω·cm². 综合考虑电学和光学性能, 在沉积温度为120 ℃下蒸镀Ni/Ag/Ti/Au (1/200/100/100 nm)并在400 ℃氧气中进行3 min退火可以得到较优化的电极. 利用此电极制作的垂直结构发光二极管在350 mA电流下的工作电压为2.95 V, 输出光功率为387.1 mW, 电光转换效率达到37.5%.     

Simulation of near-infrared photodiode detectors based on β-FeSi_2/4H-SiC heterojunctions

In this paper,we propose a near-infrared p-type β-FeSi2/n-type 4H-SiC heterojunction photodetector with semiconducting silicide(β-FeSi2) as the active region for the first time.The optoelectronic characteristics of the photodetector are simulated using a commercial simulator at room temperature.The results show that the photodetector has a good rectifying character and a good response to near-infrared light.Interface states should be minimized to obtain a lower reverse leakage current.The response spectrum of the β-FeSi2/4H-SiC detector,which consists of a p-type β-FeSi2 absorption layer with a doping concentration of 1×1015cm-3 and a thickness of 2.5 μm,has a peak of 755 mA/W at 1.42 μm.The illumination of the SiC side obtains a higher responsivity than that of the β-FeSi2 side.The results illustrate that the β-FeSi2/4H-SiC heterojunction can be used as a near-infrared photodetector compatible with near-infrared optically-activated SiC-based power switching devices.     

大学生个体发展多元化背景下“差别化”考试的改革与实践

在目前大学生个体发展多元化的社会大背景下,对所讲授的"物理化学"课程的考试方法进行了探索和实践,针对不同学生,在不显著影响考试卷面分数分布的前提下,提高对高分数段学生的区分度,降低对低数段学生的考核难度。在课程结束后的闭卷考试试卷中增加备选题,同时设计了相应的计分规则。考试结束后对试卷中"备选题"的利用情况和学生得分情况进行了综合分析和评价。实践结果表明,上述考试方法的调整达到了预期设定的目标。本实践结果也为"差别化"考试方法的推广提供了教学改革研究依据。