摘要：The underwater dry maintenance method based on a dry cabin can achieve the same maintenance quality provided on *** establishment of a reliable seal between the dry cabin and the pipe is a prerequisite for the formation of a dry *** this paper,an airbag is proposed as the means to seal the dry *** finite element software was used to study the influence of the physical characteristics of the airbag on deformation characteristics and sealing *** also studied the adaptive sealing mechanism of the airbag under the time-varying gap *** simulation results show that the peak contact stress of the airbag is close to the gas pressure,so the hardness and thickness of the airbag have little effect on *** time-varying gap conditions,the required inflation pressure increases with the size of the *** simulated relationship between the gap and the inflation pressure can be referred to in order to guide the control of the air pressure of the airbag during actual ***,the similarity between the test results and simulation results demonstrates the accuracy of the simulation results.

摘要：针对目前荒漠环境下大范围金属破片收集困难的问题,设计一款面向金属破片自主探测与回收的智能机器人。采用基于行为树(behavior tree,BT)的控制框架,提出多传感器融合的金属破片探测算法,对定位导航、目标识别和机械臂控制等基础功能进行封装,对机器人各模块进行集成并实机应用及优化。测试结果表明:该机器人在荒漠开阔环境下具有较高的收集成功率与收集效率,且表现出较好的稳定性和较低的故障率。

摘要：电催化氮还原(electrocatalytic nitrogen reduction reaction,ENRR)合成氨作为一种新兴的人工固氮工艺,具有反应条件温和、可再生能源适配性强等特点。但电催化氮还原反应电位与析氢反应(hydrogen evolution reaction,HER)电位接近,造成氮还原反应选择性降低。通过正十八-烷基硫醇对纳米多孔FeNbMoP电催化剂进行疏水修饰,增加氮气分子与催化剂表面活性位点的接触,抑制析氢反应,提高氨产率及法拉第效率。修饰后的ENRR催化剂合成氨产率为15.45μg/(h·cm^(2)),法拉第效率为6.28%,性能较未修饰的FeNbMoP催化剂提升明显。该方法有望为氮还原催化剂的理性设计提供新的思路。

摘要：以安徽省董铺—大房郢水库为例,以水库缺水率最小和补水量最少为最优准则,考虑董铺—大房郢水库水源连通工程水量补偿式调节和接受上游淠河灌区水库群补水的特殊机制,构建董铺—大房郢水库双目标优化供水调度模型,并采用基于混合交叉算子改进的NSGA-Ⅱ算法求解模型。结果表明,算数交叉算子(ACO)混合模拟二进制交叉算子(SBX)的收敛时间较单一SBX算子缩短11.48%,较单一ACO算子缩短2.58%;其中混合算子SBX-ACO求得的解集质量更好,对应评价指标世代距离(GD)值(8.13×10^(-4))、反世代距离(IGD)值(3.1×10^(-4))为所有计算方案中最小。优化调度模型求解的供水方案中两库补水量比不优化条件下的补水量减少11.5%。在计算效率及解集质量上综合验证了所提出的改进算法的有效性,同时为区域水资源优化调度提供科学依据。

摘要：准确快速测定碘量的方法对保护人类健康具有重要意义,传统的分析方法中存在样品准备复杂,需使用有毒化学试剂,前处理步骤繁琐,化学反应复杂易受干扰,分析时间长等问题,笔者选用经典的电感耦合等离子体质谱法(ICP-MS)法对昆明市碧鸡街道某村土壤样品中碘含量进行测定。降低空白干扰、优化测定条件,测试空白标准偏差S为0.0047μg/g,检出限为0.014μg/g,检测下限为0.056μg/g,均<0.2μg/g,相对标准偏差RSD在0.41%~2.78%之间,精密度RSD<10%,对数偏差ΔlgC在0.000~0.019之间,准确度ΔlgC <0.05,符合《地质矿产实验室测试质量管理规范》(DZ/T 0130.4-2006),该方法具有高灵敏度、高分辨率的特点,绿色环保,能够对地球化学样品中碘含量快速、准确测定。

摘要：In MRI (Magnetic Resonance Imaging), a crucial role of gradient coils is to image organism, meanwhile the inductance of the coils determines the speed of imaging. So it is of great importance to optimize designs of the gradient coils. The target field approach is an effective method to design the gradient coils. Having applied this method and performing many numerical tests, we achieved the designs of thex ?,y ?,z ? in which the inductance and resistance of the coils also meet the requirements.

摘要：Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi.

摘要：A newly designed hot-stamping steel alloyed by chromium （Cr） and manganese （Mn） without boron （B） addition was developed for automobile mass reduction. The experimental results showed the Cr-Mn alloyed steel could be quenched to full martensite microstructure when the cooling rate was higher than 14 ℃/s. Yield strength, tensile strength and elongation of the experimental hot stamping part reached 1 180 MPa, 1 645 MPa and 8.4% , respectively. The experimental hot stamping part possessed higher tensile strength and elongation, compared with conventional hot-stamping steel of 22MnB5. Furthermore, excellent processing flexibility would be obtained in this novel hot-stamping steel because of its lower critical cooling rate and phase transformation temperature. The design of the composition and investigations of microstructure, mechanical properties and hot-stamping processing were also studied.

摘要：Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, usually exhibit reversible host rearrangement between P-type and O-type stacking upon charge/discharge. Herein we demonstrate that such host rearrangement is unfavorable and can be suppressed by introducing transition-metal ions into sodium layers. The electrode with stabilized P3-type stacking delivers superior rate capability, high energy efficiency, and excellent cycling performance. Owing to the cation-mixing nature, it performs the lowest lattice strain among all reported cathodes for sodium-ion batteries. Our findings highlight the significance of a stable host for sodium-ion storage and moreover underline the fundamental distinction in material design strategy between lithium-and sodium-ion batteries.

摘要：A mini-vane four-rod radio frequency quadruple (RFQ) accelerator has been built for neutron imaging. The RFQ will operate at 201.5 MHz, and its length is 2.7 m. The original electric field distribution along the electrodes is not flat. The resonant frequency needs to be tuned to the operating value. And the frequency needs to be compensated for temperature change during high power RF test and beam test. As tuning such a RFQ is difficult, plate tuners and stick tuners are designed. This paper will present the tuners design, the tuning procedure, and the RF properties of the RFQ.