Surface engineering of CeO2–TiO2 composite electrode for enhanced electron transport characteristics and alkaline hydrogen evolution reaction

Herein, we report the fine tuning of electrocatalytic characteristics of CeO₂–TiO₂ composite by surface engineering to reduce overpotential and to improve exchange current density for enhanced alkaline hydrogen evolution reaction (HER). The enhanced electrocatalytic activity of the surface engineered CeO₂–TiO₂ composite through Ni and P decoration is attributed to the improved electron transport ability. The surface roughness characteristics and surface composition of electroactive species are tuned to generate high electronic conductivity on the surface engineered composite electrode surface. The developed hard electrode with leptokurtic surface (S_ku > 3) exhibited a high average roughness value (Sa) of 3 μm due to incorporation of the mesoporous catalyst material into it. Tuning of a compact and continuous electrode surface with critical composition of elements Ni (52 at.%), P (20 at.%), Ce (9 at.%) and Ti (8 at.%) furnishes the high conductivity (contact potential difference = 0.83 V) to the electrode. The developed electrode with surface engineered CeO₂–TiO₂ catalyst exhibited a low overpotential of −111 mV (at a high current density of 250 mA cm⁻²) and high exchange current density (1.6 × 10⁻¹ mA cm⁻²) with low charge transfer resistance (615 Ω cm²). High electrocatalytic activity and stability of the surface engineered CeO₂–TiO₂ catalyst electrode during alkaline (32 w/v.% NaOH) HER ensure its promising performance and applicability for long term HER.     

综放面端头及顺槽超前区顶板支护技术与实践

针对虎峰煤业2115工作面开采区煤层上部存在采空区和空巷的情况,结合工作面顺槽架棚支护的现状,通过采用“π”型梁支护管理工作面两侧端头和顺槽超前区顶板。现场实践表明,工作面回采过程中,工作面端头和超前区顶板管理较好,没有出现大面积网兜、落煤和落矸现象,顺槽金属棚能够及时回收,取得了较好的技术经济效益。     

配网工程建设时间控制

时间控制是运用科学的方法、工具,并综合运用现有资源,在规定时间内取得预期效果的一种控制手段。本文从工程时间管理的概念出发,研究了如何运用时间管理方法实现工程施工工期的管理,讨论了时间管理在工程建设中的重要性,为企业配网工程建设时间控制管理提供参考。     

异丙醇铝控制水解制备高纯拟薄水铝石和多孔氧化铝

主要进行异丙醇铝水解制备高纯拟薄水铝石和高纯多孔γ-Al_2O_3的研究。合成路线以异丙醇铝为原料,改变反应过程中水化液组成、水化温度和水化时间,制备一系列拟薄水铝石及其焙烧产物多孔γ-Al_2O_3。结果表明,水化液中异丙醇的存在会抑制无定型氢氧化铝的晶化,但也有助于形成大孔径、高比表面和大孔容的氧化铝;纯水体系下,60℃以下水化会出现三水铝石,60℃以上水化的产物则为拟薄水铝石;γ-Al_2O_3孔结构与前驱体拟薄水铝石的结晶度有关,晶粒越大的拟薄水铝石,焙烧所得氧化铝的孔径和孔容也增大。因此,水化条件的改变可以实现拟薄水铝石结构的控制,进而获得不同结构的多孔氧化铝。为由异丙醇铝水解制备高纯拟薄水铝石和多孔氧化铝的工业化提供相应的研究基础。     

Smart work packaging-enabled constraint-free path re-planning for tower crane in prefabricated products assembly process

Lack of constraint-free crane path planning is one of the critical concerns in the dynamic on-site assembly process of prefabrication housing production (PHP). For decades, researchers and practitioners have endeavored to improve both the efficiency and safety of crane path planning from either static environment or re-planning the path when colliding with constraints or periodically updating the path in the dynamic environment. However, there is a lack of approach related to the in-depth exploration of the nature of dynamic constraints so as to assist the crane operators in making adaptive path re-planning decisions by categorizing and prioritizing constraints. To address this issue, this study develops the smart work packaging (SWP)-enabled constraints optimization service. This service embraces the core characteristics of SWP, including adaptivity, sociability, and autonomy to achieve autonomous initial path planning, networked constraints classification, and adaptive decisions on path re-planning. This service is simulated and verified in the BIM environment, and it is found that SWP-enabled constraints optimization service can generate the constraint-free path when it is necessary.     

A large group linguistic Z-DEMATEL approach for identifying key performance indicators in hospital performance management

In hospital management, performance measurement is of vital importance for improving healthcare service quality. The performance of a healthcare organization is often influenced by numerous indicators, and it is unrealistic to manage them all due to the restriction of resources. In addition, the performance measurement for improvement relates to the benefits of many departments, and it is necessary for large number of experts with different backgrounds to participate in the evaluation process of healthcare indicators. In response, this study develops a large group evaluation approach using linguistic Z-numbers and decision-making trial and evaluation laboratory (DEMATEL) to determine key performance indicators (KPIs) for hospital management. For this approach, the complex and uncertain interrelation evaluations among indicators are given by experts using linguistic Z-numbers. An extended DEMATEL method is proposed to determine KPIs based on the cause and effect relationships of performance indicators. Finally, a case study in a rehabilitation hospital is presented to illustrate the effectiveness and usefulness of the proposed large group linguistic Z-DEMATEL approach. The results indicate that incidents/errors, accidents/adverse events, nosocomial infection, nursing technology pass rate, and length of stay are KPIs for the given application.     

Human Cellular Retinol Binding Protein II Forms a Domain-Swapped Trimer Representing a Novel Fold and a New Template for Protein Engineering

Domain-swapping is a mechanism for evolving new protein structure from extant scaffolds, and has been an efficient protein-engineering strategy for tailoring functional diversity. However, domain swapping can only be exploited if it can be controlled, especially in cases where various folds can coexist. Herein, we describe the structure of a domain-swapped trimer of the iLBP family member hCRBPII, and suggest a mechanism for domain-swapped trimerization. It is further shown that domain-swapped trimerization can be favored by strategic installation of a disulfide bond, thus demonstrating a strategy for fold control. We further show the domain-swapped trimer to be a useful protein design template by installing a high-affinity metal binding site through the introduction of a single mutation, taking advantage of its threefold symmetry. Together, these studies show how nature can promote oligomerization, stabilize a specific oligomer, and generate new function with minimal changes to the protein sequence.     

谈如何在预可研阶段做好工程造价控制

工程造价控制是现代工程建设、管理的核心工作之一,要求在现有基础上不断予以完善。本文以预可研阶段工程造价控制作为分析对象,论述该阶段工程造价控制的关键点,再以此为基础,分析预可研阶段的工程造价控制思路,最后从递进关联的角度,就工程造价控制的后续方法进行论述,给出构建精细化作业模式、加强数据挖掘和复用、重点项目的拆分等内容,服务后续工作。     

低能量密度炸药连续装药光面爆破技术研究

为了提高光面爆破成型质量，提出了一种低能量密度炸药连续装药光面爆破技术，利用LS DYNA进行数值模拟，对比2#岩石乳化炸药间隔装药和低能量密度炸药连续装药的应力场，然后将此技术用于长九（神山）灰岩矿四号隧洞控制爆破和露天边坡光面爆破。结果表明：2#岩石乳化炸药间隔装药模型中，装药段与非装药段测点应力峰值相差很大；而在低能量密度炸药连续装药模型中，沿炮孔轴向相同爆心距的测点应力峰值保持一致；使用低能量密度炸药进行连续装药，能够避免装药段的过度破坏和非装药段的欠挖，提高残孔率，且省去了导爆索捆绑时间，提高周边孔装药效率，节省了爆破成本。     

BIM技术在地下工程中的应用分析及展望

BIM技术以三维设计为基础,以数字信息为载体,将建筑信息贯穿于建筑的全生命周期中。然而由于地下工程的内部结构较为复杂,受地质条件影响较大,BIM技术在地下工程中的应用并不多见。叙述了BIM技术在隧道、地铁和矿井建设几种地下工程中应用的现状,并对几个典型案例进行分析,指出了BIM技术在地上工程和地下工程中应用的异同。最后,提出了目前BIM技术在地下工程中应用的问题以及对未来发展的建议。为推动BIM在我国地下工程中更广泛深入的应用提供重要参考价值。