摘要：My Memories of Old Beijing,from the perspective of contemporary Aesthetics,explores the position of people in the multicontext-overlapping society,including pre-modern,modern,post-modern eras,by the mechanism of Audio-video *** aesthetic significance lies in its representation of one way to revolt against fate in the course of Chinese modernization,its effective change of realistic people’s emotional structure,and hence one modern form of tragic humanism.

摘要：7075 aluminum alloy is often used as an important load-bearing structure in aircraft industry due to its superior mechanical *** the process of deep hole boring,the boring bar is prone to vibrate because of its limited machining space,bad environment and large elongation induced low *** reduce vibration and improve machined surface quality,a particle damping boring bar,filled with particles in its inside damping block,is designed based on the theory of vibration *** theoretical damping coefficient is determined,then the boring bar structure is designed and *** studies through impact testing show that cemented carbide particles with a diameter of 5 mm and a filling rate of 70% achieve a damping ratio of 19.386%,providing excellent vibration reduction capabilities,which may reduce the possibility of boring ***,experiments are setup to investigate its vibration reduction performance during deep hole boring of 7075 aluminum *** observe more obviously,severe working conditions are adopted and carried out to acquire the time domain vibration signal of the head of the boring bar and the surface morphologies and roughness values of the *** comparing different experimental results,it is found that the designed boring bar could reduce the maximum vibration amplitude by up to 81.01% and the surface roughness value by up to 47.09% compared with the ordinary boring bar in two sets of experiments,proving that the designed boring bar can effectively reduce *** study can offer certain valuable insights for the machining of this material.

摘要：基于1960~2008年江西省77个站点的逐日降水数据,采用地区线性矩法研究了该省极值降水频率及时空特征,包括数据的统计检验、水文气象一致区划分、最优分布线型确定、频率估计值计算、单站分析和地区分析法比较、设计值空间分布特征分析等。结果表明,皮尔逊Ⅲ型分布(PE3)和广义正态分布(GNO)是大多数一致区的最优分布;地区分析法获得的频率估计值相较于单站分析法具有很好的稳健性;不同时间段极值降水的空间分布,东北部大于西南部,大值区多位于丘陵山地,小值区多位于平原地区。

摘要：以京台高速公路某大桥为工程背景,设计了相应的新型组合高墩。通过有限元方法,考虑包括材料与几何非线性,分别采用实体单元建立了针对高墩悬臂施工阶段的模型,以及梁单元建立了全桥运营阶段模型分析其稳定性,获得其稳定承载力以及稳定系数。通过有限元参数分析,探讨了不同工况、墩身高度、软钢板厚度、屈服强度以及系梁间距对高墩稳定性的影响。计算结果表明,悬臂不平衡施工为最不利工况,组合高墩发生纵桥向压弯变形失稳,该阶段高墩的稳定系数相较悬臂平衡施工阶段下降30%。不同工况下,墩身的最不利截面处于受压侧钢管混凝土柱距离墩底0.1~0.2高度区域;随着墩身长细比增大,稳定系数出现显著下降,其破坏模式由弹塑性失稳逐渐转变为弹性失稳;软钢板厚度增大有利于稳定系数的提高;系梁间距按照传统高墩经验设计,取10 m~12 m最有利高墩稳定。基于参数分析结果,提出新型组合高墩简化模型,所得到的稳定承载力计算方法,适用于长细比超过70的组合高墩;当长细比小于70,建议采用短柱极限承载力折减方法计算。

摘要：The extended state observer (ESO) is a novel observer for a class of uncertain systems. Since ESO adopts the continuous non-smooth structure, the classical observer design theory is hard to use for ESO analysis. In this note, the self-stable region (SSR) approach, which is a nonlinear synthesis method for nonlinear uncertain systems, will be used for ESO design and its stability analysis. The advantages of the non-smooth structure in ESO for improving the convergence properties and the estimation precision will be shown.

摘要：A reverse-conducting lateral insulated-gate bipolar transistor （NI.2-LltJlS｜） with a trench oxide layer （IUL）, teaturlng a vertical N-buffer and P-collector is proposed. Firstly, the TOL enhances both of the surface and bulk electric fields of the N-drift region, thus the breakdown voltage （BV） is improved. Secondly, the vertical N-buffer layer increases the voltage drop VpN of the P-collector/N-buffer junction, thus the snapback is suppressed. Thirdly, the P-body and the vertical N-buffer act as the anode and the cathode, respectively, to conduct the reverse current, thus the inner diode is integrated. As shown by the simulation results, the proposed RC-LIGBT exhibits trapezoidal electric field distribution with BV of 342.4 V, which is increased by nearly 340% compared to the conventional RC-LIGBT with triangular electric fields of 100.2 V. Moreover, the snapback is eliminated by the vertical N-buffer layer design, thus the reliability of the device is improved.

摘要：以西巢湖为研究对象,通过室内模拟实验向已疏浚柱状样添加镧改性膨润土(LMB,商品名Phoslock■)、铜锈环棱螺、河蚬及螺蚬组合,研究钝化材料和底栖动物强化疏浚效果.采用平衡式间隙水技术(Peeper)测定间隙水NH_(4)^(+)-N和可溶性活性磷(SRP)浓度并计算沉积物-水界面交换通量,通过分级提取实验分析底泥磷形态.结果显示,在疏浚的基础上添加Phoslock,上覆水TP、SRP浓度及间隙水NH_(4)^(+)-N、SRP扩散通量显著下降,TN浓度上升为疏浚组的1.3倍.投加底栖动物相较于疏浚组上覆水氮、磷浓度及间隙水NH_(4)^(+)-N扩散通量均有不同程度的上升,SRP扩散通量下降了3.6%~53.6%.Phoslock和底栖动物均能进一步减少沉积物中TN、TP和OM的含量,削减范围分别为4.8%~12.3%、14.2%~39.2%和4.5%~20.1%.磷形态结果表明,Phoslock和河蚬可以削减沉积物中活性磷在总磷的占比,削减量分别为25.9%和22.4%,而加入铜锈环棱螺沉积物中活性磷占比为疏浚组的1.3倍.以上结果表明,Phoslock能够进一步强化疏浚对沉积物中氮、磷的控制效果;加入底栖动物降低了沉积物中污染物含量及间隙水中SRP扩散通量,但上覆水氮、磷浓度及界面NH_(4)^(+)-N扩散通量有所升高,强化疏浚效果并不理想.

摘要：讨论了客户战略选择行为的主要内涵及其对供应链管理带来的影响.引入一个不确定环境下的2级供应链模型,分析了2种竞争环境下的收益分享契约,分别考虑供应商、零售商占据领导者地位时的决策情形,求得了协调供应链的最优决策,并实现供应链总利润的合理分配.最后,用算例对结论进行了说明.

摘要：受工程经济性、埋存可行性、碳捕集适用性等诸多因素影响,海上气田膜脱碳与CO_(2)封存技术仍处于可行性研发阶段。基于南海乐东15-1高碳气田CCUS工程项目,首次利用膜脱碳技术实现CO_(2)在海上平台就地捕集及回注地层埋存的工程实践,介绍了海上气田CCUS工艺流程,针对性地开展了膜脱碳设备比选及脱碳效果影响因素分析,明确了膜脱碳效果的影响因素;基于注入极限压力理论确定CO_(2)回注压力为8~11 MPa,设计日注气量为5万m^(3)/d;针对日注气量不足开展了工况分析及流程优化,通过提高高烃气流量实现CO_(2)回注量达到额定流量。乐东15-1气田CCUS海上工程表明了“膜脱碳碳捕集技术—CO_(2)回注压缩机—回注地层碳埋存”的CO_(2)捕集与封存全流程工程技术体系在海上平台应用是可行的,所形成的工程技术经验对中国海上油气田CCUS发展及应用具有重要的工程价值。

摘要：A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxaline using H2O as the hydrogen source with 80%Faradaic efficiency and the reverse dehydrogenation of hydrogen-rich 1,2,3,4-tetrahydroquinoxaline with up to 99%yield and *** in situ generated active hydrogen atom(H^(*))is plausibly involved in the hydrogenation of quinoxaline,where a consecutive hydrogen radical coupled electron transfer pathway is ***,the MoNi_(4)alloy exhibits efficient quinoxaline hydrogenation at an overpotential of only 50 mV,owing to its superior water dissociation ability to provide H^(*)in alkaline *** situ Raman tests indicate that the Ni^(Ⅱ)/Ni^(Ⅲ)redox couple can promote the dehydrogenation process,representing a promising anodic alternative to low-value oxygen ***,electrocatalytic deuteration is easily achieved with up to 99%deuteration ratios using *** method is capable of producing a series of functionalized hydrogenated and deuterated quinoxalines.