摘要：Synthesizing a stable and efficient photocatalyst has been the most important research goal up to now. Owing to the dominant performance of g-C3N4 (graphitized carbonitride), an ordered assemble of a composite photocatalyst, Zn-Ni-P@g-C3N4, was successfully designed and controllably prepared for highly efficient photocatalytic H2 evolution. The electron transport routes were successfully adjusted and the H2 evolution was greatly improved. The maximum amount of H2 evolved reached about 531.2 μmol for 5 h over Zn-Ni-P@g-C3N4 photocatalyst with a molar ratio of Zn to Ni of 1:3 under illumination of 5 W LED white light (wavelength 420 nm). The H2 evolution rate was 54.7 times higher than that over pure g-C3N4. Moreover, no obvious reduction in the photocatalytic activity was observed even after 4 cycles of H2 production for 5 h. This synergistically increased effect was confirmed through the results of characterizations such as XRD, TEM, SEM, XPS, N2 adsorption, UV-vis DRS, transient photocurrent, FT-IR, transient fluorescence, and Mott-Schottky studies. These studies showed that the Zn-Ni-P nanoparticles modified on g-C3N4 provide more active sites and improve the efficiency of photogenerated charge separation. In addition, the possible mechanism of photocatalytic H2 production is proposed.

摘要：An efficient CuO‐modified zeolitic imidazolate framework‐9(ZIF‐9)photocatalyst is successfully prepared at room temperature under mild *** is observed that the ZIF‐9/CuO photocatalyst is effective for H2generation under visible light with sacrificial agent *** the CuO is introduced,the photocatalytic properties of ZIF‐9are greatly improved and when the content of CuO is40%,the photocatalytic activity reaches a maximum of78.74μmol *** results from the200–300nm cube structure of ZIF‐9being able to adsorb more dye molecules and the CuO,which connects with ZIF‐9,greatly improving the electronic transmission ***,the interaction between the dye molecule Eosin Y(EY)and the catalyst is also studied by transient fluorescence spectroscopy.A series of characterizations,such as SEM,TEM,XPS,XRD,UV‐vis,FTIR,transient fluorescence and photocurrent,are conducted,and the results are in good agreement with the experimental *** addition,the possible reaction mechanism over EY‐sensitized ZIF‐9/CuO under visible light irradiation is proposed.

摘要：针对滴灌管网设计参数多、过程复杂、计算量大的问题,采用Jaya算法和单位面积年成本费用最低优化方法,对设备和管道折旧费以及灌区运行管理费用等影响工程成本的因素进行研究。建立以管径、流速和管道承压等为约束条件的滴灌管网优化设计数学模型;以新疆某大型灌区内2个滴灌管网系统为例,基于Jaya算法和遗传算法对2个系统的管网管径进行优化设计;将2种算法的优化设计程序分别独立运行50次,统计每次优化结果与最优结果的相对偏差,对2种算法的优化结果进行对比分析。结果表明:基于Jaya算法得到的2个系统的最优单位面积年成本费用分别为710.53和791.62元/hm^(2),较原工程方案的单位面积年成本费用降低了16.59%和21.09%,节省投资效果明显。基于Jaya算法得到的优化结果与最优结果的相对偏差均不大于10%,表明算法收敛性能稳定,能满足实际工程设计要求。Jaya算法能省去算法调试参数的过程,且其优化能力和遗传算法相当。基于Jaya算法的滴灌管网优化设计在节省成本、算法稳定性和计算精度方面表现优越,能作为滴灌管网单目标优化设计的有效方法。

摘要：【目的】加快滴灌管网技术快速普及,提高管网系统的经济性与可靠性。【方法】以单位面积成本最低为经济目标,以不利节点的富余水头方差为可靠性目标,并考虑实际管网工程投资中的折旧费与运行管理费用建立加压滴灌管网优化设计数学模型,开展优化设计。以新疆某大型灌区内某加压滴灌管网系统为例,采用改进NSGA-Ⅱ算法方法与NSGA-Ⅱ算法对其进行优化。【结果】改进NSGA-Ⅱ算法的Pareto前沿解优于NSGA-Ⅱ算法;相同单位面积成本费用下,改进NSGA-Ⅱ算法求得的管网系统可靠性更高;经50次独立计算,改进NSGA-Ⅱ算法的均匀性指数(0.371)低于NSGA-Ⅱ算法的均匀性指数(0.404);基于改进NSGA-Ⅱ算法求解得到的单位面积成本费用为792.92元/hm^(2),较原工程方案的单位面积成本费用851.89元/hm^(2)降低了6.92%。不利节点的富余水头方差从0.15降至0.06。【结论】改进NSGA-Ⅱ算法的探索能力较NSGA-Ⅱ算法强,能够提供更优的解决方案,得到的优化方案能够同时提高管网系统的经济性和可靠性。

摘要：沙尘暴会对火星表面探测器带来发电量减少、环境温度降低、通信不稳定和仪器污染等方面的影响.为保障我国祝融号火星车的安全运行及未来火星表面探测任务的顺利开展,亟须评估沙尘暴对火星表面探测器的影响.通过系统性地回顾1997~2018年间火星表面探测器(包括着陆器与火星车)对沙尘的响应,初步认清了沙尘对火星表面探测器的影响规律——探测器太阳能电池阵列表面的尘埃以比较稳定的速率积累,而尘埃的沉积速率在沙尘暴期间,尤其是全球性沙尘暴期间会大大加快;同时,受多方面影响,电池阵列表面也会发生具有季节性模式的除尘事件.为规避沙尘暴带来的风险,在美国洞察号着陆器(InSight)的设计阶段就全面评估了沙尘暴对其着陆硬件系统及太阳能电池阵列的影响,并采取了一系列应对措施.洞察号应对沙尘暴的举措为我国未来的火星采样返回任务提供了重要启迪——前瞻性的科学指导是保障工程任务成功实施的关键.通过分析我国火星采样返回任务的初步轨道设计方案,建议未来火星探测器发射的最优窗口为2028年1月左右,以合理规避沙尘暴带来的风险.

摘要：CO_(2)选择性加氢制二甲醚(DME)是实现CO_(2)资源化利用的重要途径之一.然而,该过程面临着多方面的挑战.比如,水分子会限制CO_(2)的高效转化并诱导铜颗粒的团聚,导致催化活性与稳定性不足.此外,沸石分子筛甲醇脱水催化剂的酸性过强容易造成甲醇过度脱水生成低碳烃,导致催化选择性不足.因此,开发高效稳定的CO_(2)加氢制DME催化剂十分必要.本文通过共水解法制备了一系列镓改性的疏水二氧化硅负载铜基催化剂,并通过优化疏水基团含量以及铜与镓的比例来进一步提高催化性能.通过X射线衍射、氢气程序升温还原、X射线光电子能谱和CO吸附红外光谱等方法进行表征,结果表明,镓物种对铜纳米颗粒的电子结构进行了调控,提升了催化剂上Cuδ+物种的含量,从而抑制了逆水煤气转换反应,实现了CO选择性的降低.此外,水蒸气等温吸附、水蒸气程序升温脱附和水滴接触角测试等结果表明,引入疏水甲基基团可以调控催化剂表面的浸润性,提升水分子的扩散速率并抑制其二次吸附.在镓改性和甲基基团疏水修饰的协同作用下,Cu/Ga-SiO_(2)-20Me催化剂上CO_(2)转化率从5.5%提升至9.7%,DME选择性达到59.3%,而CO选择性则从40%降至11.3%.在100h的长周期测试中,表现出较好的催化稳定性.通过研究CO_(2)加氢催化剂(Cu/SiO_(2)-20Me)和甲醇脱水催化剂(Ga/SiO_(2)-20Me)的混合方式,探讨了疏水环境下铜和镓物种之间的协同作用.结果表明,镓改性和疏水基团的协同作用有助于串联反应的同步进行,避免了甲醇中间体的气相扩散和二次吸附.对于物理混合催化剂,由于两种活性金属存在一定的空间距离,导致铜基催化剂上生成的甲醇必须气相扩散并二次吸附于镓催化剂表面以进行后续甲醇脱水生成二甲醚反应.然而,在疏水甲基基团的作用下,抑制了极性甲醇分子的二次吸附,导致了二甲醚选择性的降低.尽管如此,对于Cu/Ga-SiO_(2)-20Me复合催化剂,铜与镓物种的毗邻性实现了CO_(2)加氢制甲醇和甲醇脱水制二甲醚串联反应能够同步进行,成功避免了甲醇中间体的气相扩散和二次吸附.此外,疏水甲基基团可以加速反应生成水的扩散,促进反应平衡正向进行,实现高效催化.综上,本文研究结果为催化系统的空间分布控制提供了有益的见解,并为设计适用于疏水催化过程的新型串联催化剂提供了参考.此外,该理念为催化剂体系的设计提供了新的思路.

摘要：用网络图的形式归纳了核岛设计采购基本逻辑框图,阐述了设计采购计划编排的基本依据和思路,按系统设计、施工设计及设备采购分类,给出了典型进度逻辑图,并分别对进度编排方案作了详细分析。

摘要：A concept of hierarchical stiffened shell is proposed in this study, aiming at reducing the imperfection sen- sitivity without adding additional weight. Hierarchical stiffened shell is composed of major stiffeners and minor stiff- eners, and the minor stiffeners are generally distributed between adjacent major stiffeners. For various types of geo- metric imperfections, e.g., eigenmode-shape imperfections, hierarchical stiffened shell shows significantly low imper- fection sensitivity compared to traditional stiffened shell. Furthermore, a surrogate-based optimization framework is proposed to search for the hierarchical optimum design. Then, two optimum designs based on two different opti- mization objectives （including the critical buckling load and the weighted sum of collapse loads of geometrically imperfect shells with small- and large-amplitude imperfections） are compared and discussed in detail. The illustrative example demonstrates the inherent superiority of hierarchical stiffened shells in resisting imperfections and the effectiveness of the proposed framework. Moreover, the decrease of imperfection sensitivity can finally be converted into a decrease of structural weight, which is particularly important in the development of large-diameter launch vehicles.

摘要：艾丽丝·默多克的两个核心概念是"好的艺术"和"自由人",她认为优秀的小说如同一栋房子,能让小说中的人物自由地生活于其中,"好的艺术"在于能把艺术形式与千奇百怪、偶然不定的现实结合在一起。《网下》、《黑王子》、《书与友谊》分别代表着默多克早、中、晚三个时期的创作特点,其中的人物关系也经历了一个从简单到复杂的变化过程。艾丽丝·默多克通过编织复杂的人物关系使得小说中人物的自由生活成为可能。

摘要：通过田野调查和文献探源,从艺术特征的角度,分析了大理西山彝成年女性盛装的工艺分类、刺绣纹样题材及服饰的色彩特征、装饰与款式等方面的构成。进一步探析了西山彝族成年女性盛装的社会文化语义和与当地信仰、审美文化的功能,以及深层次蕴含了当地女性娴熟的技艺、清新淡雅的朴素审美情趣和对幸福美满生活的追求。通过对该支系彝族服饰艺术特征的忠实记录和分析,向世人展示了她们的民族技艺和民族性格,对其服饰艺术在今后的演变发展中起到一定的资料借鉴作用。