Cf/C复合材料与纯铜的胶接辅助钎焊连接

采用胶接辅助钎焊方法,以TiH_2粉为活性元素源,环氧树脂为粘性载体,Ag-Cu共晶合金为钎料,Cu箔为应力缓冲层材料,实现了C_f/C复合材料与纯铜的钎焊连接,结果表明,接头界面处产生TiC,TiCu,Ag(s,s),Cu(s,s)等反应产物,其结构可表示为(C_f/C)/TiC+Ag(s,s)+Cu(s,s)+TiCu/Cu。通过钎焊工艺试验得出,在930℃保温25 min钎焊条件下接头的抗剪强度达到最大值30 MPa。     

A minimum projected-distance test for parametric single-index Berkson models

In this paper, we propose a minimum projected-distance test for parametric single-index regression models when the predictors are measured with Berkson errors. This test asymptotically behaves like a locally smoothing test as if the null model were with one-dimensional predictor, and is omnibus to detect all global alternative models. The test can also detect local alternative models that converge to the null model at the fastest rate that the existing locally smoothing tests with one-dimensional predictor can achieve. Therefore, the proposed test has potential for alleviating the curse of dimensionality in this field. We also give two bias-correction methods to center the test statistic. Numerical studies are conducted to examine the performance of the proposed test.     

天水地热资源开发策略

总结评价天水地热资源,依据目前世界不同的开发利用方向,分别对天水浅层地热能资源,中深层地热能资源的开发利用提出了具体方向和具体措施。     

基于智能电表大数据的异常用电检测

异常或欺诈造成的非技术性电力损失是电力公司损失的主要源头之一。智能电表的广泛使用，使得运用大数据方法实现对非技术性电力损失的有效检测成为可能。提出了一种使用监督学习进行非技术损失检测的方法。该方法基于智能仪表记录的所有信息（耗电量、异常警报等）结合辅助数据库所提供的有关每个智能电表的地理位置和技术参数的附加信息，使用最优的机器算法来深入分析用电客户的用电行为，生成异常用电客户列表。通过现场检查的结果表明，该方法能够较为准确地识别智能电网中所存在异常用电客户。     

(Metal yolk)/(porous ceria shell) nanostructures for high-performance plasmonic photocatalysis under visible light

We describe a route to the preparation of (metal yolk)/(porous ceria shell) nanostructures through the heterogeneous growth of ceria on porous metal nanoparticles followed by the calcination-induced shrinkage of the nanoparticles. The approach allows for the control of the ceria shell thickness, the metal yolk composition and size, which is difficult to realize through common templating approaches. The yolk/shell nanostructures with monometallic Pt and bimetallic PtAg yolks featuring plasmon-induced broadband light absorption in the visible region are rationally designed and constructed. The superior photocatalytic activities of the obtained nanostructures are demonstrated by the selective oxidation of benzyl alcohol under visible light. The excellent activities are ascribed to the synergistic effects of the metal yolk and the ceria shell on the light absorption, electron-hole separation and efficient mass transfer. Our synthesis of the (metal yolk)/(porous ceria shell) nanostructures points out a way to the creation of sophisticated heteronanostructures for high-performance photocatalysis.

     

Reaction environment self-modification on low-coordination Ni2+ octahedra atomic interface for superior electrocatalytic overall water splitting

Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion. In this regard, meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary. Herein, a coordination environment inheriting strategy is presented for designing low-coordination Ni²⁺ octahedra (L-Ni-8) atomic interface at a high concentration (4.6 at.%). Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode. To improve the efficiency of using the self-modification reaction environment at L-Ni-8, all of the structural features, including high atom economy, mass transfer, and electron transfer, are integrated together from atomic-scale to macro-scale. At high current density of 500 mA/cm², the samples synthesized at gram-scale can deliver low hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials of 262 and 348 mV, respectively.

     

Airline planning and scheduling: Models and solution methodologies

The airline industry is a representative industry with high cost and low profitability. Therefore, airlines should carefully plan their schedules to ensure that overall profit is maximized. We review the literature on airline planning and scheduling and focus on mathematical formulations and solution methodologies. Our research framework is anchored on three major problems in the airline scheduling, namely, fleet assignment, aircraft routing, and crew scheduling. General formulation, widely used solution approaches, and important extensions are presented for each problem and integrated problems. We conclude the review by identifying promising areas for further research.     

大采高综放工作面强动压端头顶板控制技术

为了解决大采高综放工作面回风侧端头顶板控制问题,针对马道头矿8211工作面的地质情况,通过对回风顺槽超前注浆加固,提高超前支护范围和支护强度,并对回风侧端头三角区煤壁和顶板进行化学浆加固的技术方案,有效控制了顺槽超前区围岩变形和工作面回风侧端头三角区煤壁片帮,保证了工作面端头区顶板安全。     

表面印迹耦合溶胶-凝胶法制备4-硝基酚印迹材料及性能表征

采用表面印迹和溶胶?凝胶相结合的方法，以4-硝基酚(4-NP)为模板分子、α-甲基丙烯酸(α-MAA)为功能单体、三羟甲基丙烷三甲基丙烯酸酯(TRIM)为交联剂、偶氮二异丁腈(AIBN)为引发剂，制备可选择性识别吸附去除水中4-NP污染物的印迹吸附材料，考察了4-NP与α-MAA和4-NP与TRIM摩尔比、致孔剂种类、提取液种类对所制材料吸附性能的影响，并通过正交实验优化材料制备条件，用扫描电子显微镜、傅立叶红外光谱仪、比表面积分析仪、热重?差热分析仪和纳米粒度仪等设备对最优条件下合成的材料进行了表征。结果表明，4-NP:α-MAA摩尔比为1:8，4-NP:TRIM摩尔比为1:10，致孔剂为乙醇，提取液为甲醇/乙酸(7:3，体积比)时所制印迹材料对4-NP的去除效果最佳，达6.23 μmol/g；4-NP成功印记在硅胶表面，印迹材料能特异性吸附4-NP。