Controlling non-conformities propagation in manufacturing

Aim: Recent mediatic recalls of products illustrate the losses in terms of cost and reputation induced by non-conformities reaching end customer. The purpose of this paper is to master the propagation of quality non-conformities in manufacturing processes. Most of the time, the control methods implemented to ensure the quality performance of a production system present weaknesses, inherent to their constitution. They can let non-conformities propagate along the value stream and even to the end customer inducing costly recalls for manufacturer. This paper presents a method to master non-conformities propagation in a production system. Method: In order to calibrate the proposition, two case studies have been issued on non-conformities propagation in a low-volumes industry in the energy field. Results: The proposed method combines two levels of analysis and associated improvement tools. At the event level, it proposes to build the control chart associated with the non-conformities propagation distance. At the system level, it proposes a propagation matrix to analyse the permeability of the global detection system and to identify where improvement effort has to be driven. Conclusion: The empirical results of the case studies indicate that the method is adapted in low-volume contexts.     

Defect‐Enhanced Charge Separation and Transfer within Protection Layer/Semiconductor Structure of Photoanodes

Silicon (Si) requires a protection layer to maintain stable and long‐time photoanodic reaction. However, poor charge separation and transfer are key constraint factors in protection layer/Si photoanodes that reduce their water‐splitting efficiency. Here, a simultaneous enhancement of charge separation and transfer in Nb‐doped NiO_x/Ni/black‐Si photoanodes induced by plasma treatment is reported. The optimized photoanodes yield the highest charge‐separation efficiency (η_sep) of ≈81% at 1.23 V versus reversible hydrogen electrode, corresponding to the photocurrent density of ≈29.1 mA cm^?2. On the basis of detailed characterizations, the concentration and species of oxygen defects in the NiO_x‐based layer are adjusted by synergistic effect of Nb doping and plasma treatment, which are the dominating factors for forming suitable band structure and providing a favorable hole‐migration channel. This work elucidates the important role of oxygen defects on charge separation and transfer in the protection layer/Si‐based photoelectrochemical systems and is encouraging for application of this synergistic strategy to other candidate photoanodes.     

Well‐Defined Cobalt Catalyst with N‐Doped Carbon Layers Enwrapping: The Correlation between Surface Atomic Structure and Electrocatalytic Property

Admittedly, the surface atomic structure of heterogenous catalysts toward the electrochemical oxygen reduction reaction (ORR) are accepted as the important features that can tune catalytic activity and even catalytic pathway. Herein, a surface engineering strategy to controllably synthesize a carbon‐layer‐wrapped cobalt‐catalyst from 2D cobalt‐based metal–organic frameworks is elaborately demonstrated. Combined with synchrotron radiation X‐ray photoelectron spectroscopy, the soft X‐ray absorption near‐edge structure results confirmed that rich covalent interfacial Co? N? C bonds are efficiently formed between cobalt nanoparticles and wrapped carbon‐layers during the polydopamine‐assisted pyrolysis process. The X‐ray absorption fine structure and corresponding extended X‐ray absorption fine structure spectra further reveal that the wrapped cobalt with Co–N coordinations shows distinct surface distortion and atomic environmental change of Co‐based active sites. In contrast to the control sample without coating layers, the 800 °C‐annealed cobalt catalyst with N‐doped carbon layers enwrapping achieves significantly enhanced ORR activity with onset and half‐wave potentials of 0.923 and 0.816 V (vs reversible hydrogen electrode), highlighting the important correlation between surface atomic structure and catalytic property.     

Collaborative Passivation for Dual Charge Transporting Layers Based on 4-(chloromethyl)benzonitrile Additive toward Efficient and Stable Inverted Perovskite Solar Cells

Poor carrier transport capacity and numerous surface defects of charge transporting layers (CTLs), coupled with misalignment of energy levels between perovskites and CTLs, impact photoelectric conversion efficiency (PCE) of inverted perovskite solar cells (PSCs) profoundly. Herein, a collaborative passivation strategy is proposed based on 4-(chloromethyl) benzonitrile (CBN) as a solution additive for fabrication of both [6,6]-phenyl-C61-butyric acid methylester (PCBM) and poly(triarylamine) (PTAA) CTLs. This additive can improve wettability of PTAA and reduce the agglomeration of PCBM particles, which enhance the PCE and device stability of the PSCs. As a result, a PCE exceeding 20% with a remarkable short circuit current of 23.9 mA cm⁻², and an improved fill factor of 81% is obtained for the CBN- modified inverted PSCs. Devices maintain 80% and 70% of the initial PCE after storage under 30% and 85% humidity ambient conditions for 1000 h without encapsulation, as well as negligible light state PCE loss. This strategy demonstrates feasibility of the additive engineering to improve interfacial contact between the CTLs and perovskites for fabrication of efficient and stable inverted PSCs.     

液相色谱消滞留层技术

在消滞留技术创新理论基础上,从色谱方程H=A+B/u+Cu中传质C项对柱效率的影响出发,讨论在外加电场时色谱滞留层消除与柱效率变化的关系.实验将peek色谱柱置于直流电场中,通过改变电场强度,考察一定流速下,电渗流的变化与色谱柱的柱效关系;以及一定电场强度下,不同流速与柱效的关系.结果表明色谱柱在一定电场强度下,固定相表面滞留层受到抑制,传质C项的影响削弱,流速对C项的影响降低,在实现提高柱效率的同时还可以提高流速缩短分析时间,为进一步研究高效色谱柱提供一定的基础.     

Novel biocatalysts based on S-layer self-assembly of Geobacillus stearothermophilus NRS 2004/3a: a nanobiotechnological approach

The crystalline cell-surface (S) layer sgsE of Geobacillus stearothermophilus NRS 2004/3a represents a natural protein self-assembly system with nanometer-scale periodicity that is evaluated as a combined carrier/patterning element for the conception of novel types of biocatalyst aiming at the controllable display of biocatalytic epitopes, storage stability, and reuse. The glucose-1-phosphate thymidylyltransferase RmlA is used as a model enzyme and chimeric proteins are constructed by translational fusion of rmlA to the C-terminus of truncated forms of sgsE (rSgsE (131-903), rSgsE(331-903)) and used for the construction of three principal types of biocatalysts: soluble (monomeric), self-assembled in aqueous solution, and recrystallized on negatively charged liposomes. Enzyme activity of the biocatalysts reaches up to 100 % compared to sole RmlA cloned from the same bacterium. The S-layer portion of the biocatalysts confers significantly improved shelf life to the fused enzyme without loss of activity over more than three months, and also enables biocatalyst recycling. These nanopatterned composites may open up new functional concepts for biocatalytic applications in nanobiotechnology.     

无机薄膜电致发光器件中绝缘层材料的研究

薄膜电致发光（TFEL）技术将戍为平板显示技术的潮流和主体。简要介绍了平板显示技术的发展，同时对无机薄膜电致发光器件中绝缘层材料的选择进行了探讨。     

Conjugated Polyelectrolytes as Multifunctional Passivating and Hole‐Transporting Layers for Efficient Perovskite Light‐Emitting Diodes

Metal halide perovskites (MHPs) have attracted significant attention as light‐emitting materials owing to their high color purities and tunabilities. A key issue in perovskite light‐emitting diodes (PeLEDs) is the fabrication of an optimal charge transport layer (CTL), which has desirable energy levels for efficient charge injection while blocking opposite charges and enabling perovskite layer growth with reduced interfacial defects. Herein, two poly(fluorene‐phenylene)‐based anionic conjugated polyelectrolytes (CPEs) with different counterions (K⁺ and tetramethylammonium (TMA⁺)) are presented as multifunctional passivating and hole‐transporting layers (HTLs). The crystal growth of MHPs grown on different HTLs is investigated through X‐ray photoelectron spectroscopy, X‐ray diffraction, and density functional theory calculation. The CPE bearing the TMA⁺ counterions remarkably improves the growth of perovskites with suppressed interfacial defects, leading to significantly enhanced emission properties and device performance. The luminescent properties are further enhanced via aging and electrical stress application with effective rearrangement of the counterions on the interfacial defects in the perovskites. Finally, efficient formamidinium lead tribromide‐based quasi‐2D PeLEDs with an external quantum efficiency of 10.2% are fabricated. Using CPEs with varying counterions as a CTL can serve as an effective method for controlling the interfacial defects and improving perovskite‐based optoelectronic device properties.     

Mo2C过渡层对金刚石-碳膜场发射均匀性的影响

在经过不同特殊预处理的金属钼衬底上沉积了金刚石 -碳膜 ,分别用X射线衍射谱 (XRD)、拉曼光谱 (Raman)和扫描电子显微镜 (SEM)对样品进行了分析和测试 ,并研究了样品器件的场发射特性。结果发现在金属钼衬底和金刚石 -碳膜之间形成的Mo2 C过渡层与金刚石 -碳膜场发射均匀性有着密切的联系     

New methods for monitoring corrosion parameters for articles and joints

A set of methods is developed for the first time for monitoring the corrosion of articles and joints, that provide an objective estimate of the dynamics of the whole corrosion process. __________ Translated from Izmeritel’naya Tekhnika, No. 6, pp. 66–69, June, 2006.