摘要：The design and synthesis of high‐performance and low‐cost electrocatalysts for the hydrogen evolution reaction(heR),a key half‐reaction in water electrolysis,are *** to their modest hydrogen adsorption energy,ruthenium(Ru)‐based nanomaterials are considered outstanding candidates to replace the expensive platinum(Pt)‐based heR *** this study,we developed an adsorption‐pyrolysis method to construct nitrogen(N)‐doped graphene aerogel(N‐GA)‐supported ultrafine Ru nanocrystal(Ru‐NC)nanocomposites(Ru‐NCs/N‐GA).The particle size of the Ru‐NCs and the conductivity of the N‐GA substrate can be controlled by varying the pyrolysis *** experiments reveal revealed that 10 wt%Ru‐NCs/N‐GA nanocomposites require overpotentials of only 52 and 36 mV to achieve a current density of 10 mA cm^(−2) in 1 mol/L HClO4 and 1 mol/L KOH electrolytes for heR,respectively,which is comparable to 20 wt%Pt/C *** from the ultrafine size and uniform dispersion of the Ru‐NCs,the synergy between Ru and the highly conductive substrate,and the anchoring effect of the N atom,the Ru‐NCs/N‐GA nanocomposites exhibit excellent activity and durability in the pH‐universal heR,thereby opening a new avenue for the production of commercial heR electrocatalysts.

摘要：单排内外啮合行星机构广泛应用于军用车辆及飞机,为满足行星机构总布置紧凑性及传动效率高的要求,以单级行星减速器为优化对象,以太阳轮齿数、模数、齿宽等参数为优化变量,建立装配条件、同轴条件、相邻条件、传动比条件及齿轮强度等约束条件,构建基于遗传算法的对称不等距行星减速器优化设计的数学模型,并利用模糊集合理论从最优解集中选择出合理参数作为最终设计结果。经优化计算,优化后机构传动效率得到提高,同时减速器体积比原来减小12.91%。提出的融合模糊集合理论和遗传算法的优化思路,实现了行星减速器的多目标优化。

摘要：现存孟浩然诗集中颇多写于病中的诗篇,似乎表明孟浩然是一个多病的诗人,正如他在《岁暮归南山》一诗中所吟诵的:"不才明主弃,多病故人疏",但其病中诗似未能引起学界足够的关注。通过分析这些病中诗,我们发现,孟浩然真正关心和在意的并非家国社稷,亦非天下苍生,而只是他个人对于功名和享乐的追求。越到晚年,诗人的功名之心越淡,而享乐之念越浓,甚至最终因王昌龄的造访而浪情欢谑,"食鲜疾动"而死。可以说,孟浩然病中的这些体验和感受才是诗人区别于盛唐诸家的根本特质。

摘要：滤波器作为通信系统的关键器件,其小型化具有重要意义。设计了一款带有衰减极点的层叠式LTCC低通滤波器,该无源滤波器截止频率fr=1 GHz,实际测试结果与仿真结果吻合较好。器件外形尺寸为3.0 mm×1.5 mm×1.2 mm,与EIA1206尺寸代码的封装尺寸兼容,具有较强的实用性。

摘要：A flow mathematical model with multiple horizontal wells considering interference between wells and fractures was established by taking the variable width conductivity fractures as basic flow *** a semi-analytical approach was proposed to model the production performance of full-life cycle in well pad and to investigate the effect of fracture length,flow capacity,well spacing and fracture spacing on estimated ultimate recovery(EUR).Finally,an integrated workflow is developed to optimize drilling and completion parameters of the horizontal wells by incorporating the productivity prediction and economic *** is defined as nested optimization which consists of outer-optimization shell(i.e.,economic profit as outer constraint)and inner-optimization shell(i.e.,fracturing scale as inner constraint).The results show that,when the constraint conditions aren’t considered,the performance of the well pad can be improved by increasing contact area between fracture and formation,reducing interference between fractures/wells,balancing inflow and outflow between fracture and formation,but there is no best compromise between drilling and completion *** only the inner constraint condition is considered,there only exists the optimal fracture conductivity and fracture *** considering both inner and outer constraints,the optimization decisions including fracture conductivity and fracture length,well spacing,fracture spacing are achieved and *** the fracturing scale is small,small well spacing,wide fracture spacing and short fracture should be *** the fracturing scale is large,big well spacing,small fracture spacing and long fracture should be used.

摘要：Simultaneous inhibition of MDM2 and CDK4 may be an effective treatment against glioblastoma. A collection of chiral spirocyclic tetrahydronaphthalene(THN)-oxindole hybrids for this purpose have been developed. Appropriate stereochemistry in THN-fused spirooxindole compounds is key to their inhibitory activity: selectivity differed by over 40-fold between the least and most potent stereoisomers in time-resolved FRET and KINOMEscan~? in vitro assays. Studies in glioblastoma cell lines showed that the most active compound ent-4g induced apoptosis and cell cycle arrest by interfering with MDM2-P53 interaction and CDK4 activation. Cells treated with ent-4g showed up-regulation of proteins involved in P53 and cell cycle pathways. The compound showed good anti-tumor efficacy against glioblastoma xenografts in mice. These results suggested that rational design, asymmetric synthesis and biological evaluation of novel tetrahydronaphthalene fused spirooxindoles could generate promising MDM2-CDK4 dual inhibitors in glioblastoma therapy.

摘要：With the development of high-speed railways in China,more than 2000 high-speed trains will be put into *** and efficiency of railway transportation is increasingly *** have designed a high availability quadruple vital computer (HAQVC) system based on the analysis of the architecture of the traditional double 2-out-of-2 system and 2-out-of-3 *** HAQVC system is a system with high availability and safety,with prominent characteristics such as fire-new internal architecture,high efficiency,reliable data interaction mechanism,and operation state change *** hardware of the vital CPU is based on ARM7 with the real-time embedded safe operation system (ES-OS).The Markov modeling method is designed to evaluate the reliability,availability,maintainability,and safety (RAMS) of the *** this paper,we demonstrate that the HAQVC system is more reliable than the all voting triple modular redundancy (AVTMR) system and double 2-out-of-2 ***,the design can be used for a specific application system,such as an airplane or high-speed railway system.

摘要：利用超声波提取相思藤多糖,采用单因素实验和正交实验,研究料液比、超声功率、超声提取温度和超声作用时间对相思藤多糖提取效果的影响。并通过对1,1-二苯基-2-三硝基苯肼自由基(DPPH·)和·OH的清除实验结果和Fe3+还原实验结果来评价相思藤多糖的抗氧化活性。结果得出优化工艺条件为:相思藤干粉1g,蒸馏水60mL,提取温度60℃,超声功率180 W,作用时间80 min,在此条件下相思藤多糖的提取率为13.30%。抗氧化试验结果显示相思藤多糖对DPPH·和·OH的清除能力以及对Fe3+的还原能力都较强,且在一定范围内其抗氧化作用与浓度呈现良好的量效关系。相思藤多糖具有较强的抗氧化活性,为相思藤的资源利用和开发提供依据。

摘要：The ability to controlled introduction of defects, particularly twin defects in Pt-based nanocrystals （NCs） provides a possibility to regulate the performance of Pt-based nanocatalyst. However, because of the high internal strain energy existed in twinned structures, the fabrication of defects in Pt-based NCs is sufficiently challenging. here we demonstrate a ＂low-temperature interface-induced assembly＂ approach that provides precise control over Pt-Cu nanoparticles assembled at the hexadecylamine/water interface, yielding onion-like Pt-Cu NCs exposed a high density of twin defects. Moreover, a bending mechanism is proposed to elucidate the appearance of twin defects and lattice expanding （contraction） based on aberration corrected scanning transmission electron microscopy analysis. This work opens new routes to engineer defects in metal- based alloy NCs, enabling more opportunities in catalysis.

摘要：目的探索基于地域文化的创意产品设计的方法和模型。方法对岳麓书院文化进行分类,采集和整理岳麓书院文化的基本信息,通过因子分析法定义岳麓书院文化的评价因子,并结合调查问卷定量筛选出最具有地域特色的文化元素,对该部分文化元素进行设计解读,充分挖掘文化元素中形态、色彩和内涵因子,最终作为设计元素运用到创意产品的设计中。结论通过对岳麓书院文化元素的获取与创新的实践,验证了方法和模型的有效性,这将对基于地域文化的创意产品的开发起到指导性作用,促进文化创意产业的发展。