CO2-CH4重整NiO／γ-Al2O3催化剂制备方法与其催化性能的关系研究

分别采用自然浸渍法（1#）、超声波浸渍法（2#）、旋转真空浸渍法（3#）和胶体磨循环浸渍法（4#）制备NiO／γ-Al2O3催化剂,对其进行TPR和XRD分析,TPR分析结果表明,四种试样的还原温度均低于800℃,均不存在自由NiO物种;XRD分析结果表明,焙烧后的四种试样均存在NiO和NiAl10O16尖晶石两种晶相。四种试样的CH4／CO2重整反应30h评价实验结果表明,胶体磨循环法所制备的催化剂评价结果最好,其CH4和CO2转化率分别为93．5％和83．5％,n（H2）：n（CO）=0．84：1。     

Stabilization of natural gas foams using different surfactants at high pressure and high temperature conditions

Natural gas foam can be used for mobility control and channel blocking during natural gas injection for enhanced oil recovery, in which stable foams need to be used at high reservoir temperature, high pressure and high water salinity conditions in field applications. In this study, the performance of methane (CH₄) foams stabilized by different types of surfactants was tested using a high pressure and high temperature foam meter for surfactant screening and selection, including anionic surfactant (sodium dodecyl sulfate), non-anionic surfactant (alkyl polyglycoside), zwitterionic surfactant (dodecyl dimethyl betaine) and cationic surfactant (dodecyl trimethyl ammonium chloride), and the results show that CH₄-SDS foam has much better performance than that of the other three surfactants. The influences of gas types (CH₄, N₂, and CO₂), surfactant concentration, temperature (up to 110°C), pressure (up to 12.0 MPa), and the presence of polymers as foam stabilizer on foam performance was also evaluated using SDS surfactant. The experimental results show that the stability of CH₄ foam is better than that of CO₂ foam, while N₂ foam is the most stable, and CO₂ foam has the largest foam volume, which can be attributed to the strong interactions between CO₂ molecules with H₂O. The foaming ability and foam stability increase with the increase of the SDS concentration up to 1.0 wt% (0.035 mol/L), but a further increase of the surfactant concentration has a negative effect. The high temperature can greatly reduce the stability of CH₄-SDS foam, while the foaming ability and foam stability can be significantly enhanced at high pressure. The addition of a small amount of polyacrylamide as a foam stabilizer can significantly increase the viscosity of the bulk solution and improve the foam stability, and the higher the molecular weight of the polymer, the higher viscosity of the foam liquid film, the better foam performance.     

Utilization of coordinating green solvents for high quality methylammonium bismuth iodide thin films for photovoltaic applications

Photovoltaic performances of the bismuth-based solar cells are profoundly affected by the thin film quality of the photoactive layer. Herein, we report on various green solvent system to obtain the highly crystalline, pinhole free and homogeneously methylammonium bismuth iodide (MBI) active layer. The MBI structure prepared with tetrahydrofuran:2-ethoxy-ethanol (THF-2ETO) solvent system was found to have the best film quality. Adding 0.05 M 2ETO as the co-solvent is sufficient to produce high quality BiI₃ and MBI thin films. According to the X-ray photoelectron spectroscopy (XPS) analyzes, we have demonstrated that there is an interaction between BiI₃ and 2ETO according to the concentration of 2ETO added to the main THF. Our study clarifies the importance of THF-2ETO solvent system that can accelerate the evolution of the Bi-based solar cells by creating high-quality BiI₃ or MBI thin films.     

Energy-optimized cluster head selection based on enhanced remora optimization algorithm in underwater wireless sensor network

With the technological advancements, wireless sensor network (WSN) has played an impeccable role in monitoring the underwater applications. Underwater WSN (UWSN) is supported by WSN but subjected to data dissemination in an acoustic medium. Due to challenging conditions in underwater scenario, the limited battery resources of these sensor nodes stem to a crucial research problem that needs to address the energy-efficient routing in UWSN. In this research work, we intend to propose an energy-optimized cluster head (CH) selection based on enhanced remora optimization algorithm (ECERO) in UWSN. Since CH devours the maximum energy among the nodes, we perform selection of CH based on EROA while considering energy, Euclidean distance from sink, node density, network's average energy, acoustic path loss model and lastly, the adaptive quantity of CHs in the network. Further, to reduce the load on CH node, we introduce the concept of sleep scheduling among the closely located cluster nodes. The proposed work improves the performance of recently proposed EOCSR algorithm by great magnitude which claims to mitigate hot-spot problem, but EOCSR still suffers from the same due to relaying a large magnitude of data.     

USB总线接口芯片CH371及其应用

CH371是一种新型USB通用总线接口芯片。利用该芯片可在不了解任何USB协议或固件程序甚至驱动程序的情况下，轻松地将并口或串口产品升级到USB接口。文中介绍了该接口芯片的主要特点和引脚功能，给出了CH371与其它总线进行接口的几种应用电路，同时给出了CH371与MCS-51单片机的接口程序。     

钙钛矿敏化太阳电池制备工艺的优化研究

近年来,有机金属卤化物钙钛矿太阳电池因制备条件温和、光吸收强、能耗低、光电转化效率高等优点成为备受瞩目的研究热点。本文采用一步法制备钙钛矿材料甲胺碘化铅（CH3NH3PbI3）,并以廉价的聚（3-己基噻吩） （P3HT）为空穴传输材料在大气环境下制备钙钛矿敏化太阳电池。其中,通过调控TiO2浆料与松油醇、乙基纤维素的配比,分别制备具有250 nm、600 nm和1 000 nm三种不同厚度的TiO2纳米颗粒多孔薄膜光阳极,并系统考察钙钛矿前驱体溶液旋涂量对敏化电极结构形貌及光吸收性能的影响。太阳电池光电特性测试结果表明：当TiO2多孔层厚度为600 nm、钙钛矿前驱体溶液的旋涂量为40 μl时,CH3NH3PbI3能够较为完全地覆盖在多孔TiO2的表面,且钙钛矿材料的晶粒尺寸合适,TiO2孔道结构未被堵塞,有利于空穴导体的填充以及空穴的转移与传输,优化后的太阳电池光电转化效率达到5.17%。     

PN(CH2)nP配体/Cr(III)/DMAO/AlEt3催化乙烯齐聚

合成并表征了N-(2-(二苯基膦酰)乙基)-N-甲基-1,1-二苯基膦胺(L1)、N-(2-(二苯基膦酰)乙基)-N-异丙基-1,1-二苯基膦胺(L2)和N-(3-(二苯基膦酰)丙基)-N-异丙基-1,1-二苯基膦胺(L3)3种新型PN(CH₂)_nP型配体。3种配体分别与CrCl₃(THF)₃、脱除挥发性组分的甲基铝氧烷(Dried methylaluminoxane,DMAO)和三乙基铝(Aluminumtriethyl,AlEt₃)组成催化体系,考察其催化乙烯齐聚的性能。结果表明：该类配体组成的催化体系,具有催化活性高和C₆～C₈线性α烯烃选择性高的特点;L2组成的催化体系,在4.0 MPa和100 ℃时,催化活性可达1.71×10.7 g/(mol Cr·h);在1.0 MPa和100 ℃时,1-己烯和1-辛烯总选择性达到93%。与配体L1相比,配体L2骨架N上的异丙基增加了催化剂空间体积,显著提高了催化活性及催化体系的热稳定性。     

CH40型钢的研制

CH40型钢为内卷边槽钢。生产厂家要求在现有φ89高频直缝焊管机组上完成生产任务。依据机组的结构特点,为其完成机组改造及整套孔型设计,给出孔型变形图。     

Effect of cation exchange capacity of soil on stabilized soil strength

While a certain correlation between the cation exchange capacity (CEC) of the soil and the strength of the cement stabilized soil has been reported, the mechanism remains unclear. In this research, a set of soil samples with different CECs were stabilized with different proportions of cement and calcium hydroxide (Ca(OH)₂, CH). The influence of soil CEC on the strength of the stabilized soil was investigated by analyzing the CH saturation in the pore solution and measuring the strength of the stabilized soil specimens. It is revealed that cation exchange in the soil can reduce the CH saturation of the stabilized soil. If the CEC of the soil is too high, the CH in the pore solution of the stabilized soil cannot reach the saturation level, and further cation exchange would then consume the Ca²⁺ ions which should be originally used to generate calcium silicate hydrate, thus result in the poor strength of the stabilized soil.