对称池阻抗模型的化简与分析

从测量电解池的电化学边界条件出发，对Ｊ．Ｒ．Ｍａｃｄｏｎｌｄ关于对称池的电化学交流阻抗谱（ＥＩＳ）精确解进行了分类化简，给出了不同边界条件下的理想阻抗谱的近似简化关系式、对应等效电路以及各种电路元件与材料性能参数的关系式．由于此模型的通常性，可用来处理半导体、绝缘体、液体、固体电解质、熔融盐及导电聚合物阻抗频谱的实验数据．用此化简模型，以新型原位电化学复合的干态苯胺／聚硫橡胶膜的电化学阻抗数据处理为例，介绍了对称池电化学阻抗数据的处理方法．

颅内占位CT征──纵裂池不对称或闭塞征

分析100例颅内幕上占位性病变CT图像，结果发现脑室受压、中线结构移位等占位效应者，均有纵裂池不对称或闭塞；无明显占位效应的小灶颅内占位性病变，绝大多数纵裂池不对称。认为纵裂地不对称是幕上占位性病变敏感的间接征。

基于检测增强型YOLOv3-tiny的道路场景行人检测

为了给驾驶员提供实时准确的行人信息、减少交通事故的发生,提出一种检测增强型YOLOv3-tiny(detection of enhanced YOLOv3-tiny,DOEYT)行人检测算法.创建鲁棒的特征提取网络,首先使用非对称最大池化进行下采样,防止随着感受野增大行人横向特征的丢失;其次使用Hardswish作为卷积层的激活函数优化网络性能;最后使用GC(globe context)自注意力机制获得全文特征信息.在分类回归网络部分,采用三尺度检测策略,提升小尺度行人目标的检测精度;使用k-means++算法重新生成数据集锚框,提高网络收敛速度.构建行人检测数据集并分为训练集和测试集,对DOEYT算法的性能进行试验验证.结果表明,非对称最大池化、Hardswish函数、GC自注意力机制分别使平均准确率AP提高14.4%、7.9%、10.8%;DOEYT算法在测试集上检测的平均准确率高达91.2%,检测速度为103帧/s,可见该算法可快速准确地检测行人,降低交通事故发生的风险.

Ni doped La_(0.6)Sr_(0.4)FeO_(3-δ) symmetrical electrode for solid oxide fuel cells

The conventional Ni cermet anode suffers from severe carbon deposition and sulfur poisoning when fossil fuels are used. Alternative anode materials are desired for high performance hydrocarbon fuel solid oxide fuel cells （SOFCs）. We report the rational design of a very active Ni doped La0.6Sr0.4FeO3‐δ（LSFN） electrode for hydrocarbon fuel SOFCs. Homogeneously dispersed Ni‐Fe alloy nanoparticles were in situ extruded onto the surface of the LSFN particles during the operation of the cell. Sym‐metric SOFC single cells were prepared by impregnating a LSFN precursor solution onto a YSZ （yt‐tria stabilized zirconia） monolithic cell with a subsequent heat treatment. The open circuit voltage of the LSFN symmetric cell reached 1.18 and 1.0 V in humidified C3H8 and CH4 at 750？？, respective‐ly. The peak power densities of the cells were 400 and 230 mW/cm2 in humidified C3H8 and CH4, respectively. The electrode showed good stability in long term testing, which revealed LSFN has good catalytic activity for hydrocarbon fuel oxidation.

A small molecular electron acceptor based on asymmetric hexacyclic core of thieno[1,2-b]indaceno[5,6-b']thienothiophene for efficient fullerene-free polymer solar cells

A novel A-D-A （acceptor-donor-acceptor） type non-fullerene small molecule, A201, consisting of an asymmetric thieno[1,2-b]indaceno[5,6-b＇lthienothiophene （TITI＇） unit as middle D part and 2-（3-oxo-2, 3-dihydroinden-l-ylidene） malononitrile （IC） groups as end-capped A parts was designed and synthesized. The asymmetric TITT building block showed a higher dipole moment of 0.85 Debye （1 Debye = 3.33564 × 10^-3μcm） compared with the symmetric analogues of indacenodithiophene （IDT） and indacenodithieno[3,2-b]thiophene （IDTr） of 0.098 and 0.13 Debye, respectively. The solution-processed bulk heterojunction solar cells using a benzotriazole （BTA）-based polymer of J71 as donor and A201 as acceptor, showed a power conversion efficiency （PCE） of 9.36% with an open-circuit voltage （Voc） of 0.88 V, a short-circuit current Use） of 13.15 mA cm^-2, and a fill factor （FF） of 0.B7, under the illumination of AM 1.5G at 100 mW cm^-2. The high PCE of this material combination could be attributed to its broad absorption spectrum and the high hole mobility （#h） and electron mobility （μh） of 9.56 × 10^-4 and 5.1× 10^-4 cm^2 V^-1 s^-1, respectively. These results indicate that the asymmetric electron-donating segments are promising to construct A-D-A type small molecular acceptors, which could largely enhance the diversity of building blocks to design photovoltaic materials.

The behavior of deep convective clouds over the warm pool and connection to the Walker circulation

As the deep convective clouds(DCCs) over the western Pacific and Indian Ocean warm pool may play different roles in the climate system, variations in DCC properties over these two sectors are investigated and compared. The DCC intensity and area varies more significantly in the Indian Ocean than the western Pacific sector, while the DCC frequency is comparable in both sectors at the seasonal scale. Although the Indian Ocean sector is strongly dominated by the seasonal evolution, the interannual variations in the two sectors are comparable for all three DCC properties(frequency, intensity, and area). Besides,Walker circulation is closely correlated with the interannual variability of DCCs in both sectors. The Walker circulation strengthens(weakens) as the DCCs shift eastward(westward) over the Indian Ocean sector and westward(eastward) over the western Pacific sector. When more or stronger DCCs occur over the Indian Ocean sector(western Pacific sector), the Walker circulation becomes stronger(weaker) and shifts westward(eastward). Interestingly, the response of the Walker circulation to DCC variability over the warm pool is asymmetry. The asymmetry response of the Walker circulation to the negative and positive DCC anomaly may be related to the non-linearity internal variability of the atmosphere. DCCs over the Indian Ocean sector have a much weaker nonlinear correlation with the Walker circulation than DCCs over the western Pacific sector.

Preparation of microtubular solid oxide fuel cells based on highly asymmetric structured electrolyte hollow fibers

A simple and cost-effective method has been developed for the fabrication of microtubular solid oxide fuel cells (MT-SOFCs). Highly asymmetric electrolyte hollow fibers composed of a thin dense skin layer and a thick porous substrate are first prepared by a modified phase inversion/sintering technique. The porous substrate is then formed into the anode by deposition of a Ni catalyst via an electroless plating method inside the pores while the thin dense skin layer serves directly as the electrolyte film of the fuel cells. A porous cathode layer is produced on the outer surface of the Ni-deposited hollow fibers by slurry coating and subsequent sintering to form a complete micro tubular fuel cell. The process has been employed to fabricate yttrium stabilized zirconia (YSZ) supported Ni-YSZ-YSZ-La0.6Sr0.4Co0.2Fe0.8O3-(LSCF) microtubular fuel cells. The maximum output of the resulting cells is 159.6 mW cm-2 at 800 °C when using H2 as the fuel feed and air as the oxidant.