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21.
In order to explore new materials capable of producing the new energy hydrogen, co-catalyst CoP was successfully modified Z-scheme hetero-junction CdS@WO3 to achieve efficient splitting of water under visible light. With the lactic acid solution as sacrificial agent, the H2 production was 736.89 μmol corresponding the apparent quantum yield of 1.72%, which was 20.2 and 24.5 times than pure CdS and WO3, respectively. The results of XRD, TEM and FESEM characterization showed that the catalyst has obvious micro-morphology and high crystallinity. The valence distribution and composition of elements in the catalyst were measured by XPS. UV-vis, PL and electrochemical detection showed that the catalyst has excellent optical and electrical properties such as rapidly photo-generated charge transfer efficiency. Not only the energy band structure of the catalyst was calculated and analyzed, simultaneously the charge transfer mechanism and HER mechanism were explored and proposed.  相似文献   
22.
In the present paper an indirect model based on neural networks is presented for modelling the rough honing process. It allows obtaining values to be set for different process variables (linear speed, tangential speed, pressure of abrasive stones, grain size of abrasive and density of abrasive) as a function of required average roughness Ra. A multilayer perceptron (feedforward) with a backpropagation (BP) training system was used for defining neural networks. Several configurations were tested with different number of layers, number of neurons and type of transfer function. Best configuration for the network was searched by means of two different methods, trial and error and Taguchi design of experiments (DOE). Once best configuration was found, a network was defined by means of trial and error method for roughness parameters related to Abbott–Firestone curve, Rk, Rpk and Rvk.  相似文献   
23.
Testing analog and mixed-signal circuits is a costly task due to the required test time targets and high end technical resources. Indirect testing methods partially address these issues providing an efficient solution using easy to measure CUT information that correlates with circuit performances. In this work, a multiple specification band guarding technique is proposed as a method to achieve a test target of misclassified circuits. The acceptance/rejection test regions are encoded using octrees in the measurement space, where the band guarding factors precisely tune the test decision boundary according to the required test yield targets. The generated octree data structure serves to cluster the forthcoming circuits in the production testing phase by solely relying on indirect measurements. The combined use of octree based encoding and multiple specification band guarding makes the testing procedure fast, efficient and highly tunable. The proposed band guarding methodology has been applied to test a band-pass Butterworth filter under parametric variations. Promising simulation results are reported showing remarkable improvements when the multiple specification band guarding criterion is used.  相似文献   
24.
The air-kerma is one of the most important physical quantities in ionizing radiation dosimetry. The measurement of airkerma rate in narrow-spectrum series is th...  相似文献   
25.
Indirect Immunofluorescence (IIF) images are increasingly being used for the diagnosis of autoimmune diseases. However, the analysis of this kind of images has until now reached a comparatively low level of automation, if compared with other medical imaging techniques. The Special Issue on the Analysis and Recognition of Indirect Immunofluorescence Images of the Pattern Recognition journal aims at providing a comprehensive evaluation of the state of the art for the staining pattern classification problem, through the adoption of a common experimental protocol and the testing of all the methods on a publicly available dataset.  相似文献   
26.
A new stream of research indicates that framing effects are based on emotional as well as cognitive processes. However, it is not entirely clear whether emotions mediate framing effects and what the moderators of emotional mediation processes are. To address these questions, we conducted an experiment in which the framing of responsibility for a social problem was manipulated (ambivalent vs. high‐responsibility frame). We find that the high‐responsibility frame increased the preference for punitive measures by increasing responsibility beliefs and eliciting anger. Furthermore, we find that trait anger moderates the framing effect on anger and that responsibility beliefs are positively associated with anger intensity. The significance of these findings for framing research and suggestions for future studies are discussed.  相似文献   
27.
东鞍山含碳酸盐难选铁矿石分步浮选工艺研究   总被引:10,自引:0,他引:10  
介绍了东鞍山烧结厂含碳酸盐难选铁矿石的工艺矿物学及浮选分离特性,提出了处理难选碳酸盐铁矿的浮选新工艺--分步浮选,即第一步在中性条件下采用正浮选分选菱铁矿;第二步在高pH值下采用反浮选分选赤铁矿。实验室闭路浮选试验结果表明,在浮选给矿品位为52.30% 时,采用分步浮选工艺可以获得铁品位 66.34%、回收率71.60%的铁精矿。  相似文献   
28.
Thermally induced phase separation (TIPS) was used to produce spherical polypropylene–zirconia composite powder for selective laser sintering (SLS). The influence of the composition of the composite starting powder and the SLS parameters on the density and strength of the composite SLS parts was investigated, allowing realizing SLS parts with a relative density of 36%. Pressure infiltration (PI) and warm isostatic pressing (WIPing) were applied to increase the green density of the ZrO2–PP SLSed parts. Infiltrating the SLS parts with an aqueous 30 vol.% ZrO2 suspension allowed to increase the sintered density from 32 to 54%. WIPing (135 °C and 64 MPa) of the SLS and SLS/infiltrated complex shape green polymer–ceramic composite parts prior to debinding and sintering allowed raising the sintered density of the 3 mol Y2O3 stabilized ZrO2 parts to 92 and 85%, respectively.  相似文献   
29.
介绍并分析了间接蒸氨工艺应用中出现的问题。结合生产实际对原有工艺进行了改进,使蒸氨废水指标更稳定,蒸氨工艺更符合节能环保的要求。  相似文献   
30.
碳酸化塔CO2浓度的软测量   总被引:1,自引:1,他引:0  
通过联碱碳酸化塔中与CO2浓度相关且可在线实时检测的参数,如进气量、温度、压力等,构造出CO2浓度的多元一次回归模型。并根据自适应辩识原理,对变量形式进行变换,导出可变窗口自适应辩识方法,建立了联碱碳酸化塔中CO2浓度估计器,利用该估计器的模型参数和可在线实时检测的相关参数,以及在线估计算法,使得联碱碳酸化塔中CO2浓度在线检测成为可能。  相似文献   
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