金属异质波导阵列中的表面等离激元传播特性

提出了一种新的一维金属异质波导阵列的设计方案,即波导芯区周期调制的金属波导阵列.数值模拟的结果表明,金属波导芯区的周期调制引起波导中传播的表面等离激元有效折射率的周期调制,从而可在特定的波段打开一个表面等离激元带隙(如1550nm附近).通过引入合适的缺陷波导单元,可获得特定波长的高品质因子(Q=556)的表面电磁模共振.这一结果可用于设计亚波长的布拉格反射器、光发射器、滤波器等,有可能被用于未来的集成光路.     

稀土钐离子可见荧光量子产率的精确测试与计算

采用积分球配以CCD光谱测试系统,在蓝色半导体发光二极管激发下,对Sm3 掺杂的低声子能量、高折射率铋碲酸盐玻璃的荧光光谱进行测试。实现了荧光发射特性绝对评价为目的的绝对光谱功率分布测定,为发光与激光材料荧光发射特性的精确测量与表征提供了一种准确方法。荧光测试系统由直径为25.4cm的积分球配以CCD探测器组成,通过标准卤素灯定标,辅助卤素灯校正积分球内环境变化,解析出样品的绝对光谱功率分布,并进一步计算出光量子数分布,求得荧光量子产率等荧光特征参量。测试与计算结果表明,对应可见区Sm3 四个特征发射峰,总荧光量子产率为7.55%。     

Modified constructions of binary sequences using multiplicative inverse

Two new families of finite binary sequences are constructed using multiplicative inverse. The sequences are shown to have strong pseudorandom properties by using some estimates of certain exponential sums over finite fields. The constructions can be implemented fast since multiplicative inverse over finite fields can be computed in polynomial time.     

一种吸油烟机声品质满意度分级限值评定方法

声品质作为一种描述吸油烟机噪声听觉感知特性的手段已经被行业所接受,团体标准T/CAS 341–2019《吸油烟机噪声声品质测试方法》给出了吸油烟机声品质测试与建模方法,同时通过声品质指数给出了声品质的数值化表达.该标准为各厂商定量描述声品质提供了依据,但目前仍缺乏对产品声品质满意度级别的划分方法,这不利于声品质技术的推...     

HPLC法测定豆制品中游离异黄酮的含量

利用高效液相色谱法（HPLC）对豆制品中的大豆黄素和染料木素的含量进行测定,从而研究豆制品加工中的游离大豆异黄酮分布情况。     

Nickel-catalyzed cross-electrophile allylation of vinyl bromides and the modification of anti-tumour natural medicine β-elemene

Herein, we present a facile and efficient allylation method via Ni-catalyzed cross-electrophile coupling of readily available allylic acetates with a variety of substituted alkenyl bromides using zinc as the terminal reductant. This Ni-catalyzed modular approach displays excellent functional group tolerance and a broad substrate scope, which the creation of a series of 1,4-dienes including several structurally complex natural products and pharmaceutical motifs. Moreover, the coupling strategy has the potential to realize enantiomeric control. The practicality of this transformation is demonstrated through the potent modification of the naturally antitumor active molecule β-elemene.

Herein, we present a facile and efficient allylation method via Ni-catalyzed cross-electrophile coupling of readily available allylic acetates with a variety of substituted alkenyl bromides using zinc as the terminal reductant.     

“Click handle”-modified 2′-deoxy-2′-fluoroarabino nucleic acid as a synthetic genetic polymer capable of post-polymerization functionalization

The functions of natural nucleic acids such as DNA and RNA have transcended genetic information carriers and now encompass affinity reagents, molecular catalysts, nanostructures, data storage, and many others. However, the vulnerability of natural nucleic acids to nuclease degradation and the lack of chemical functionality have imposed a significant constraint on their ever-expanding applications. Herein, we report the synthesis and polymerase recognition of a 5-(octa-1,7-diynyl)uracil 2′-deoxy-2′-fluoroarabinonucleic acid (FANA) triphosphate. The DNA-templated, polymerase-mediated primer extension using this “click handle”-modified FANA (cmFANA) triphosphate and other FANA nucleotide triphosphates consisting of canonical nucleobases efficiently generated full-length products. The resulting cmFANA polymers exhibited excellent nuclease resistance and the ability to undergo efficient click conjugation with azide-functionalized molecules, thereby becoming a promising platform for serving as a programmable and evolvable synthetic genetic polymer capable of post-polymerization functionalization.

Polymerase-mediated incorporation of a “click handle”-modified fluoroarabinonucleic acid (cmFANA) triphosphate produces a new class of nuclease-resistant, evolvable genetic polymers that can be functionalized with azide-containing molecules.     

The Antioxidant and Hypolipidemic Effects of Mesona Chinensis Benth Extracts

In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia.     

氨对硅基铁纳米薄膜高温重凝核的影响

采用弧过滤离子沉积系统（arc filtered deposition,AFD）在纯硅表面制备铁纳米薄膜。研究了750℃下铁纳米薄膜在氢气氛围以及氨气氛围中重凝核的规律。研究表明,在氢气氛围中,铁纳米薄膜重凝核以后形成的铁纳米颗粒随薄膜的厚度增加以及保温时间的延长而增大;但在氨气氛围中,铁纳米薄膜重凝核后形成的纳米颗粒的尺寸随保温时间的变化更为复杂：在氨气作用的初始阶段,铁颗粒的尺寸随氨气作用时间的延长而逐渐变大,但一段时间以后,铁颗粒的尺寸又随氨气作用时间的延长而变小,直到铁颗粒平均直径达到一个最小值（大约在氨气介入后的12min）,随后铁颗粒的尺寸又逐渐变大,并最终达到一稳定值。     

离子对rod-pinch二极管工作特性的影响

 利用PIC粒子模拟方法,结合对同轴结构二极管工作模式的半解析描述,研究了离子存在与否对rod-pinch二极管（RPD）工作特性的影响。模拟给出了二极管的伏安特性、不同时刻电子和离子的相空间分布以及空间电流分布等。结果表明随着电流逐渐增大,其工作模式从空间电荷限制流依次向弱箍缩流和磁绝缘流转变。只有存在离子的情况下,电子才能沿着阳极杆表面运动并在其末端发生箍缩,表明RPD中离子电流的存在对于RPD工作是必需的。