摘要：Building highly active and stable noble metal single atom(MSA)catalyst onto photocatalyst materials for nitrogen reduction reaction(NRR)and CO2 reduction reaction(CRR)is a key to future renewable energy conversion and storage *** we present a design strategy to optimize the stability and electronic property of noble metal single atoms(MSAs,M=Rh,Pd,Ag,Ir,Pt,Au)catalyst supported on g-C3N4 and 2H-MoS2 photocatalysts towards NRR and *** results indicate that the MSAs tend to be trapped at the anion-vacancy sites of photocatalyst rather than the pristine photocatalyst *** anion vacancy can promise the MSAs with an optimized electron-captured ability in the photoexcitation process,thus decreasing the energy barriers of NRR and CRR on ***,it is revealed that the N-vacancy-stabilized Ir SA on g-C3N4 and the S-vacancy-stabilized RhSA on 2H-MoS2 own the lowest energy barrier in ***,for CRR,the HCOOH is the main product on MSAs supported by gC3N4 and *** N-vacancy-stabilized PdSA on g-C3N4 and the S-vacancy-stabilized AuSA on 2H-MoS2 show the lowest energy barrier for HCOOH production in *** finding offers an approach to design specific active MSA centres on photocatalysts by the anion vacancy engineering.

摘要：Photocatalytic hydrogen production represents a promising strategy for clean, sustainable, and environmentfriendly energy supply. Up to now, great efforts have been devoted to designing the photocatalysts with noble metal as co-catalyst for visible-light-driven hydrogen evolution, while more efficient photocatalytic systems are still a major challenge. Herein, we report a facile strategy for synthesizing faceto-face ultrathin Pd nanosheets-amorphous carbon nitride(Pd NSs-ACN) structure with large contacting interface and short electronic transmission pathway, which can work as an efficient photocatalyst for hydrogen production. The synthesis starts with the growth of ultrathin Pd NSs, followed by assembly with the visible-light-response ACN through a simple stirring and annealing procedure. The resultant two dimensional face-to-face structures deliver an average hydrogen generation rate of 1.45 mmol h-1g-1 at a temperature of 25℃,almost 2.6 times higher than that of Pd Nps-ACN with particle-to-face structural feature. The efficient photocatalytic activity is ascribed to the formation of high-density of active sites between ultrafine face-to-face contacted Pd NSs and the ACN, which cooperate more synergistically towards photocatalytic hydrogen production. The face-to-face engineered Pd NSs-ACN hybrids also offer a good stability revealed by photocatalytic hydrogen production measurements. The extraordinary performance highlights a powerful engineering model for designing other face-to-face contacting co-catalyst/photocatalysts, which will be a great impetus to optimize new catalytic transformations.

摘要：Photocatalytic technology holds great promise in renewable energy and environmental ***,we report the synthesis of a class of polyaniline-sensitized BiOCI core/shell nanosheets with visible-light photocatalytic activity by a one-step oxidative polymerization method and show how the hybrid nanosheet boosts the photocatalytic activity and stability for degradation of Rhodamine B (RhB).In this unique structure,the ultrathin polyaniline (PANI)as a shell with the thickness of about 1-2nm,can widen the response of the catalyst to visible light to boost photocatalysis and the BiOCI core can promote the separation of photogenerated carriers from the *** demonstrate that the optimized BiOCl/ PANI core/shell photocatalyst shows nearly three times higher photocatalytic activity for the degradation of RhB than pure BLOC1and also shows high *** work provides a new strategy for the design of a highly efficient hybrid photo- catalyst driven by visible light.

摘要：以复合制导的XX反舰导弹典型作战过程为背景,着重分析了复合制导红外末制导交班误差和红外本身误差对红外探测器捕获跟踪目标概率的影响,为目前流行的中末交接班制导导弹设计提供一个误差分析标准,文中针对误差影响因素作了仿真分析,并从分析中得到了一个交接捕获跟踪的较佳状态,以此状态作为参考能使中末制导导弹制导更加具有实际意义。

摘要：本系统采用自动化质量控制、提高检测精度以及实时监控与反馈等手段来实现滤棒制造过程埋线质量的有效监测。系统设计主要由图像采集模块、图像处理算法以及系统软硬件实现等部分组成,以保证检测的精度及实时性。在实践中,系统的使用减少了人工成本,经济与社会价值显著。

摘要：现有的电力时序数据库集群拓展方法拓展响应时间较低,导致集群效率较差,因此基于回溯搜索研究了一种新的电力时序数据库集群拓展方法。通过数据库集群搜索拓扑结构的邻接矩阵,计算电力数据库中关联性较高的数据拓扑结构,直接明确数据搜索的目标,缩小数据搜索可确定的范围。针对搜索拓扑内的电力数据,采用回溯搜索算法中的分层回溯原则,为数据库集群内数据搜索行为增加约束条件。根据开关矩阵判断数据节点之间的关系,实现电力时序数据库的集群拓展。实验结果表明,基于回溯搜索的电力时序数据库集群拓展方法的拓展响应时间低于0.5 s,集群效率在98%以上。

摘要：400Hz逆变器需具备一定的过载能力,以使挂接于交流母线电子设备故障时继电保护装置动作。然而,过载时滤波电感感值会显著下降,传统有源阻尼控制难以适应LC滤波器谐振频率f_(r)宽范围变化。此外,考虑到400Hz逆变器低次谐波频率较高,其往往落于控制带宽之外且接近于f_(r),低次谐波抑制和系统稳定性较难得以兼顾。为实现滤波电感参数扰动下400Hz逆变系统稳定性提升和宽频率范围低次谐波抑制,文中采用二阶滤波器对有源阻尼内环进行相位超前补偿,提出有源阻尼自适应控制律,其根据预设阻尼比在线调整不同工况下内环反馈比例系数,以实现滤波器谐振峰相同阻尼效果。进一步,提出采用附加相角补偿的特定次谐波谐振控制,并给出相位补偿角度的设计方法,其可实现控制带宽外以及f_(r)附近低次谐波抑制。最后,搭建一台600W单相400Hz逆变器,实验结果表明,所提控制策略可以实现不同工况下滤波电感参数扰动时良好的系统稳定性和低次谐波抑制效果。

摘要：Mooring systems play an important role for semi-submersible rigs that drill in deepwater.A detailed analysis was carried out on the mooring of a semi-submersible rig that conducted a trial well drilling at a deepwater location in the South China Sea in *** rig was 30 years old and had a shallow platform with a designed maximum operating water depth of 457 *** the mooring analysis,a mooring design was given that requires upgrading of the rig’s original mooring *** upgrade included several innovations,such as installing eight larger anchors,*** the original anchors and inserting an additional 600 m of steel wires with the existing *** this was done to enhance the mooring capability of the rig in order for the rig to be held in position to conduct drilling at a water depth of 476 *** overall duration of the drilling was 50 days and the upgraded mooring system proved to be efficient in achieving the goal of keeping the rig stationary while it was drilling the trial well in the South China *** successful campaign demonstrates that an older semi-submersible rig can take on drilling in deep water after careful design and proper upgrading and modification to the original mooring system.

摘要：为获得铝合金板式节点网壳杆件的平面内计算长度,对5根网壳杆件进行轴心受压稳定承载性能试验。采用ABAQUS中的实体单元建立试件的有限元模型,通过反弯点法得出了杆件的计算长度。研究结果表明,铝合金板式节点的半刚性构造使得网壳杆件的平面内计算长度与其净长度有关。基于ANSYS软件平台,采用非线性弹簧单元COMBIN39建立了考虑铝合金板式节点半刚性的网壳模型。通过对不同荷载模式下网壳一阶屈曲荷载及杆件临界荷载的对比,发现压杆周围杆件受压时的刚度退化对其约束的削弱作用可使其计算长度系数放大约33%,因此杆件的受压刚度退化在稳定分析中不可忽略。通过对杆端约束刚度的推导和弹性稳定微分方程的求解,得到了考虑铝合金板式节点半刚性和周围杆件约束的网壳杆件平面内计算长度系数,并制成了供设计使用的计算用表,可为铝合金板式节点网壳杆件的设计提供依据。

摘要：为研究铝合金板式节点网壳结构在实际火灾下的响应,针对一网壳缩尺模型进行了结构受火试验。采用柴油油池火作为火源,考虑不同的火源功率、火源位置和通风条件,设计了8个受火场景。在结构受火试验前,进行了两次柴油燃烧特性试验,并将试验结果与经典羽流模型的预测值进行了对比分析。结构受火试验结果表明:空间温度场在大空间火灾下分布不均匀,且火源位置和火源功率对结构温度场分布具有较大影响;在各受火场景中,大功率火源位于结构角部且通风条件不佳时为最不利火灾场景;在该火灾场景下,所测得的最高空气温度为128℃,而杆件和节点板的最高实测温度分别为92℃和84℃;在所有结构模型受火试验过程中,均发现网壳发生起拱变形,但试验结束后变形可恢复,且未观测到其他破坏现象。对试验过程进行数值模拟,结果表明火灾下结构的热膨胀变形可能提升其稳定承载力,因此在设计时建议分别基于有热膨胀变形和无热膨胀变形的结构进行稳定承载力分析,并取两者结果中的较小值作为结构火灾下承载力的设计值。