微纳米胶囊缓释凝胶的制备与性能评价

为达到延缓聚合物凝胶成胶时间的目的,以部分水解聚丙烯酰胺、交联剂J₁（醋酸铬）和J₂（酚醛树脂）、除氧 剂D-异抗坏血酸、疏水性气相纳米二氧化硅为原料制备了一种微纳米缓释凝胶。利用疏水颗粒在水溶液中的自 组装作用将交联剂溶液封装于颗粒胶囊内部后加入聚合物溶液中,通过缓慢释放交联剂来实现延缓成胶时间的 目的。研究了pH值对疏水颗粒封装能力以及疏水颗粒浓度对胶囊热稳定性、凝胶成胶时间、凝胶强度的影响。 研究结果表明,缓释胶囊适用的溶液pH 值范围为2～10,胶囊中疏水纳米二氧化硅颗粒用量为10%时,胶囊在 240 h 后30 ℃下分水率为3.33%,120 ℃下分水率为26.67%,稳定性良好;使用疏水纳米二氧化硅颗粒用量为 10%的胶囊后,凝胶在30 ℃下成胶时间由48 h 延长至486 h,在120 ℃下由1 h 延长至144 h;30 ℃下成胶的凝胶 储能模量G''由43 Pa 增至313 Pa,屈服应力由102 Pa 增至202 Pa。疏水颗粒制备的缓释胶囊具有较好的热稳定 性,不仅能够延缓凝胶的成胶时间,而且能够增加凝胶的强度。     

固定式碳酸钠混拌撬自动控制系统

碳酸钠混拌橇自动控制系统采用先进的自动化技术,实现了生产的自动化.在减轻劳动量的同时,也保证了配液的质量、速度,瞬时量及发液的准确性和连续性.     

Anisotropic Spectroscopy and Electrical Properties of 2D ReS2(1–x)Se2x Alloys with Distorted 1T Structure

2D black phosphorus (BP) and rhenium dichalcogenides (ReX₂, X = S, Se) possess intrinsic in‐plane anisotropic physical properties arising from their low crystal lattice symmetry, which has inspired their novel applications in electronics, photonics, and optoelectronics. Different from BP with poor environmental stability, ReX₂ has low‐symmetry distorted 1T structures with excellent stability. In ReX₂, the electronic structure is weakly dependent on layer numbers, which restricts their property tunability and device applications. Here, the properties are tuned, such as optical bandgap, Raman anisotropy, and electrical transport, by alloying 2D ReS₂ and ReSe₂. Photoluminescence emission energy of ReS_{2(1? x )}Se_{2 x} monolayers (x from 0 to 1 with a step of 0.1) can be continuously tuned ranging from 1.62 to 1.31 eV. Polarization behavior of Raman modes, such as ReS₂‐like peak at 212 cm^?1, shifts as the composition changes. Anisotropic electrical property is maintained in ReS_{2(1? x )}Se_{2 x} with high electron mobility along b‐axis for all compositions of ReS_{2(1? x )}Se_{2 x} .     

钻井平台爆炸性环境中柴油发动机防爆控制系统方案分析及应用

在油田作业的工况下常会有爆炸性气体存在的可能,以国家标准为参考依据,结合柴油发动机在国内固井作业的实际应用情况,分析了柴油发动机点燃危险源由壳体高温表面、明火(排气口的火星、火花)、机械摩擦造成静电集聚释放、电气元件等组成。提出了满足防爆要求的柴油发动机控制系统方案,对进气及排气系统、运行参数监测系统、启动及停机系统、紧急停机系统进行了相关分析。该控制系统可以确保柴油发动机在爆炸性气体环境下安全可靠运行。     

老顶的来压过程及其预报

本文通过理论分析与现场实例分析,认为老顶来压是一个过程,它包括老顶的断裂下沉和台阶下沉两个主要阶段。在来压过程中,回采工作面的矿压显现特征量均呈“驼峰”型。因此,可采用矿压显现特征量的前一个峰值(断裂下沉)来预报后一个峰值(台阶下沉),以防止压垮性事故的发生。     

中原黄金冶炼厂技术改进评述及流程改进意见

从技术和经济效益上评术字中原冶炼硬币和年来的主要工艺技术改造，探讨了盐浸脱铜工艺的必要性和提高银回收率的途径。     

β-SiC的静态性质和能带结构

在从头计算的LMTO—ASA方法中引用Lowdin微扰法,计算了β-SiC晶体的总能E_(tot),平衡晶格常数α_0,体模量B_0,体模量的压力微商B_0~'和能带结构,计算结果与从头计算的赝势法等的计算结果基本相符,与实验值的偏差合理,但计算量小,进一步证明利用微扰计入空d态影响的LMTO—ASA方法是行之有效的方法。     

水域水位变化对邻近复合地基支承路堤稳定性的影响研究

针对在水域边发生的复合地基支承路堤滑塌事故的问题,为研究水域及其水位变化对邻近复合地基支承路堤稳定性的影响,采用有限差分方法建立了三维数值模型,研究了水域及其水位变化对于桩体受力以及路堤变形的影响。结果表明:水域的存在将大幅提高桩体的受力,水域与路堤形成的先后顺序不同其影响也不一致,水位的突然降低将大幅增加桩体发生弯曲破坏的风险,对路堤的稳定性产生不利影响。不考虑水域以及水域水位变化的影响采用传统复合地基稳定分析方法将显著高估路堤稳定性。     

Self-supporting nanoporous gold-palladium overlayer bifunctional catalysts toward oxygen reduction and evolution reactions

The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are crucial processes for energy conversion/storage systems, such as fuel cells, metal–air batteries, and water splitting. However, both reactions are severely restricted by their sluggish kinetics, thus requiring highly active, cost-effective, and durable electrocatalysts. Herein, we develop novel bifunctional nanocatalysts through surface nanoengineering of dealloying-driven nanoporous gold (NPG). Pd overlayers were precisely deposited onto the NPG ligament surface by epitaxial layer-by-layer growth. More importantly, the obtained NPG-Pd overlayer nanocatalysts exhibit remarkably enhanced electrocatalytic activities toward both the ORR and OER in alkaline media, benchmarked against a stateof- the-art Pt/C catalyst. The improved electrocatalytic performance is rationalized by the unique three-dimensional nanoarchitecture of NPG, enhanced Pd utilization efficiency from precise control of the Pd overlayers, and change in electronic structure, as revealed by density functional theory calculations.

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采用步进梁式加热炉的油井管调质生产线

由于油井管的工作条件非常恶劣,因此对其综合力学性能要求较高。要达到所需的力学性能,一般要对其进行调质处理。介绍了采用步进梁式加热炉的油井管调质生产线及所采用的先进工艺、先进装置、先进技术和其使用效果。