摘要：目的:超燃冲压发动机燃烧室中氢气的燃烧性能引起了研究者的广泛兴趣。本文旨在探讨不同压比下超燃冲压发动机燃烧室的燃烧性能以及壁面凹腔的影响,为双模态超燃冲压发动机燃烧室设计提供参考。创新点:1.研究压比变化过程中超燃向亚燃的转换过程;2.研究壁面凹腔设置对模态转换过程的影响。方法:采用数值模拟方法研究不同来流条件下,压比和壁面凹腔设置对基于支板的超燃冲压发动机燃烧室中模态转换过程的影响。结论:1.壁面喷注压强对流场结构影响很大,特别是对于亚燃到超燃的模态转换过程和燃烧性能,当壁面喷注压强大约为支板喷注压强一半时,效果最好;2.壁面凹腔能帮助稳定流场,但也会带来一定的混合效率和燃烧效率损失,同时壁面凹腔能帮助延迟从超燃模态向亚燃模态的转换时间,这也从一定程度上说明带凹腔的燃烧室更加适合于超燃模态。

摘要：With the development in spinning technology, the improvement of cotton fiber quality is becoming more and more important. The main objective of this research was to construct a high-density genetic linkage map to facilitate marker assisted selection for fiber quality traits in upland cotton (Gossypium hirsutum L.). A genetic linkage map comprising 421 loci and covering 3814.3 cM, accounting for approximately 73.35% of the cotton genome, was constructed using an F2 population derived from cross GX1135 (P 1 )×GX100-2 (P 2 ). Forty-four of 49 linkage groups were assigned to the 26 chromosomes. Fiber quality traits were investigated in F2 population sampled from individuals, and in F2:3 , and F2:4 generations sampled by lines from two sites and one respectively, and each followed a randomized complete block design with two replications. Thirty-nine quantitative trait loci were detected for five fiber quality traits with data from single environments (separate analysis each): 12 for fiber length, five for fiber uniformity, nine for fiber strength, seven for fiber elongation, and six for fiber micronaire, whereas 15 QTLs were found in combined analysis (data from means of different environments in F2:3 generation). Among these QTLs, qFL-chr5-2 and qFL-chr14-2 for fiber length were detected simultaneously in three generations (four environments) and verified further by combined analysis, and these QTLs should be useful for marker assisted selection to improve fiber quality in upland cotton.

摘要：In this paper,we introduce a novel approach to automatically regulate receptive fields in deep image parsing *** previous work which placed much importance on obtaining better receptive fields using manually selected dilated convolutional kernels,our approach uses two affine transformation layers in the network’s backbone and operates on feature *** maps are inflated or shrunk by the new layer,thereby changing the receptive fields in the following *** use of end-to-end training,the whole framework is data-driven,without laborious manual *** proposed method is generic across datasets and different *** have conducted extensive experiments on both general image parsing tasks,and face parsing tasks as concrete examples,to demonstrate the method’s superior ability to regulate over manual designs.

摘要：文章将势流理论方法与波谱分析方法相结合,对浅吃水中高速排水型船舶的尾浪进行了数值计算,采用势流理论方法对船舶近域的波浪进行计算,将获取的部分波高数据(或试验数据)作为已知数据,采用波谱函数法进行分析求解,获取波幅谱函数,从而求解远域船舶的尾浪。文中采用试验数据对理论计算结果进行了验证,两者吻合较好。同时结合船模试验结果,探讨了水深、浮态等对单、双体船船舶尾浪的影响,该研究结果可为低尾浪船型的设计和优化提供参考。

摘要：研究目的:为超大跨度斜拉桥抗风设计与抖振控制提供参考。研究方法:基于ANSYS建立了苏通大桥三维有限元模型,并在MATLAB平台模拟了苏通大桥三维脉动风场。考虑主梁断面气动自激力,进行了苏通大桥抖振时域分析。根据苏通大桥动力特性和抖振时域分析结果,重点分析了多重调谐质量阻尼器(MTMD)用于抖振控制的参数敏感性。考虑MTMD的控制效果、建造费用、施工难度及鲁棒性等因素建立了关于MTMD设计参数的目标函数,并基于一阶优化算法进行目标函数最优解的非线性搜索,据此获得了MTMD在约束条件下的最优设计参数。重要结论:1.苏通大桥侧向抖振位移主要由第一阶侧弯振型控制,竖向抖振位移主要由第一阶竖弯振型控制;***的控制效果对设计参数的变化十分敏感,其中质量比和频带宽敏感性更强;***的最优设计参数可以通过一阶优化算法获得,并可通过零阶优化算法对优化结果进行验证;4.采用优化后的MTMD设计参数,苏通大桥的抖振响应可以得到明显抑制,且侧向抖振控制效果更加明显。

摘要：变速风力发电机对于电网扰动、故障以及电网电压跌落非常敏感,当上述情况发生时风力发电机将从电网切除,直到电网恢复正常才能重新投入运行。如何在电网发生扰动时保持风力发电机的正常运行是一个有挑战性的课题。未来的电网规范甚至要求在电网发生故障时风力机组仍能保持运行,这就要求必须安装保证风电机组低电压运行的控制装置。文中针对采用全载换流器与电网进行连接的异步风力发电机组提出了相应的风电机组低电压控制器及控制策略,无须进行硬件改造即可实现电网故障情况下风电机组不退出运行。其中,风电机组电气子系统控制器基于无差拍控制策略进行设计。算例给出了300kW的风电机组在30%电压跌落情况下的暂态过程,没有加入控制器之前风电机组将停机,加入之后则可以保持运行,验证了所提方法的正确性。

摘要：Rechargeable Li batteries as electrochemical energy storage and conversion devices are continuously changing human life. In order to meet the increasing demand for energy and power density, it is essential and urgent to exploit the electrode materials with high capacity and fast charge transfer(for Li-ion and Li-S batteries) and electrocatalysts with high activity(for rechargeable Li-O2 batteries). The high capacity is attributed to high electron transfer number and low molecular weight of the electrode materials. Combined with proper nanostructure design, the electronic transfer and ionic conductivity will be improved. This review summarizes recent efforts to apply electrode materials for Li-ion batteries with multi-electron reaction, Li-S batteries, and efficient electrocatalysts for Li-O2 batteries. The methods to enhance the cycling and rate performance have been discussed in detail. Advanced rechargeable Li batteries with multi-electron reaction will become the research emphasis in the future.

摘要：A novel 1×2 polymer electro-optic(EO)switch based on seven vertical-turning serial-coupled microrings is proposed for dropping crosstalk and obtaining flat boxlike *** device structure,theory and formulation are presented,and the microring resonance order and coupling gaps are *** switching voltage of the device for obtaining crosstalk lower than 30 dB under through state is decided to be about 1.86 *** the operation voltages of 0 V(drop state)and 1.86 V(through state),the switching performance is characterized,and the output spectrum is *** calculation results show that the crosstalk at through state and that at drop state are 30.2 dB and 53.2 dB,respectively,while the insertion losses are 0.86 dB and 3.18 dB,*** to the seven serial-coupled microrings resonance structure,the proposed switch reveals the favorable boxlike spectrum compared with the simple device with only one microring,and thus the crosstalk under drop state is improved from 26.8 dB to 53.2 *** to the low crosstalk,this device can be used in optical networks-on-chip for signal switching and routing.

摘要：设计合成了系列新的拟天然联三苯类衍生物,并对其生物活性进行了分析.其中4-氨基-(1,1':4,1'-三联苯)-3-二醇(17)具有最强的MDA-MB-435细胞增殖抑制活性, IC_(50)为(0.20±1.12)μmol/L,显著优于我们之前报道的同类化合物X1和***松弛实验结果表明,化合物17具有较强的DNA拓扑异构酶Ⅱα的抑制活性,但是对DNA拓扑异构酶Ⅰ活性无明显抑制作用.分子模拟对接分析结果进一步验证, C环上的氮取代基对化合物17选择性抑制DNA拓扑异构酶IIα活性有重要作用,为设计合成新的联三苯类高效拓扑异构酶Ⅱα抑制剂提供了新思路.

摘要：Due to their unique surface chemistry,highly adjustable metal components,hydrophilicity,and high carrier concentrations,MXenes are applied in a variety of *** to other two-dimensional(2D)materials,building heterostructures with additional materials to form a 3D porous architecture for MXenes can significantly enhance their functionality and ***,the open structures and well-defined pathways of these 3D structured MXenes can improve ionic and electronic transport,thereby promoting their applications in electrochemical energy storage,sensing,catalysis,and *** this review,the recent efforts made on preparing 3D porous MXenes with heterostructures,focusing on MXenes/C,MXenes/inorganics,and MXenes/polymers were *** discussion covers aspects ranging from the design to synthesis of 3D porous MXenes,and their applications in photocatalysis,environmental monitoring and electrochemical energy *** review is concluded by presenting the prospects and insights on exploring the relationships between the porosity formation mechanisms,properties and applications of the 3D porous MXenes *** review can provide meaningful guidance for the design,fabrication and application of 3D porous MXenes in high-performance materials and devices.