Refilling Nitrogen to Oxygen Vacancies in Ultrafine Tungsten Oxide Clusters for Superior Lithium Storage

Morphological engineering of nanosized transitional metal oxides shows great promise for performance improvement, yet limited efforts have been attempted to engineer the atomic structure. Oxygen vacancy (V_O) can boost charge transfer leading to enhanced performance; yet excessive V_O may impair the conductivity. Herein, tungsten oxide is atomically tailored by incorporating nitrogen heteroatoms into the oxygen vacancies. The efficient nitrogen‐filling into the oxygen vacancies is evidenced by the electron paramagnetic resonance spectroscopy and X‐ray absorption spectroscopy. The coordinated N atoms play a crucial role in facilitating the charge transfer and maintaining efficient lithium‐ion diffusion. Consequently, the tungsten oxide with N‐filled oxygen vacancies exhibits superior lithium‐ion storage performance.     

NaCa0.6V6O16·3H2O as an Ultra‐Stable Cathode for Zn‐Ion Batteries: The Roles of Pre‐Inserted Dual‐Cations and Structural Water in V3O8 Layer

Rechargeable aqueous batteries with Zn²⁺ as a working‐ion are promising candidates for grid‐scale energy storage because of their intrinsic safety, low‐cost, and high energy‐intensity. However, suitable cathode materials with excellent Zn²⁺‐storage cyclability must be found in order for Zinc‐ion batteries (ZIBs) to find practical applications. Herein, NaCa_0.6V₆O₁₆·3H₂O (NaCaVO) barnesite nanobelts are reported as an ultra‐stable ZIB cathode material. The original capacity reaches 347 mAh g^?1 at 0.1 A g^?1, and the capacity retention rate is 94% after 2000 cycles at 2 A g^?1 and 83% after 10 000 cycles at 5 A g^?1, respectively. Through a combined theoretical and experimental approach, it is discovered that the unique V₃O₈ layered structure in NaCaVO is energetically favorable for Zn²⁺ diffusion and the structural water situated between V₃O₈ layers promotes a fast charge‐transfer and bulk migration of Zn²⁺ by enlarging gallery spacing and providing more Zn‐ion storage sites. It is also found that Na⁺ and Ca²⁺ alternately suited in V₃O₈ layers are the essential stabilizers for the layered structure, which play a crucial role in retaining long‐term cycling stability.     

Light waveguiding in bioinspired peptide nanostructures

Basic optical properties of bioinspired peptide nanostructures are deeply modified by thermally mediated refolding of peptide secondary structure from α‐helical to β‐sheet. This conformational transition is followed by the appearance in the β‐sheet structures of a wideband optical absorption and fluorescence in the visible region. We demonstrate that a new biophotonic effect of optical waveguiding recently observed in peptide/protein nanoensembles is a structure‐sensitive bimodal phenomenon. In the primary α‐helical structure input, light propagates via optical transmission window demonstrating conventional passive waveguiding, based on classical optics. In the β‐sheet structure, fluorescent (active) light waveguiding is revealed. The latter can be attributed to completely different physical mechanism of exciton‐polariton propagation, characterized by high effective refractive index, and can be observed in nanoscale fibers below diffraction limit. It has been shown that peptide material requirements for passive and active waveguiding are dissimilar. Original biocompatibility and biodegradability indicate high potential future applications of these bioinspired waveguiding materials in precise photobiomedicine towards advanced highly selective bioimaging, photon diagnostics, and optogenetics.     

In Pursuit of Closed‐Loop Supply Chains for Critical Materials: An Exploratory Study in the Green Energy Sector

A closed‐loop supply chain (CLSC) is considered not only an important solution for ensuring sustainable exploitation of materials, but also a promising strategy for securing long‐term availability of materials. The latter is especially highlighted in the materials criticality discourse. Critical raw materials (CRMs), being exposed to supply disruptions, create an uncertain operational environment for many industries, particularly for green energy technologies that employ multiple CRMs. However, recycling rates of CRMs are very low and engagement of companies in CLSC for CRM is limited. This study examines factors influencing CLSC for CRM development in photovoltaic panels and wind turbine technologies. The aim is to analyze how the factors manifest themselves in different companies along the supply chain and to identify enabling and bottleneck conditions for implementation of CLSC for CRM. The novelty of the study is twofold: the focus on material rather than product flows, and examination of factors from a multiactor perspective. The evidence obtained suggests that the manufacturing companies and reverse supply‐chain operators engaged in the study take different perspectives (product vs. material) regarding development of CLSC for CRM and thus emphasize different factors. The findings underline the need for interactions between supply‐chain actors, a sound competitive environment for recycling processes, and investment in technologies and infrastructure development if CLSC for CRM is to be developed. The paper provides implications for practitioners and policy makers for implementation of CLSC for CRM, and suggests prospects for further research.     

Although there is no Physical Short‐Term Scarcity of Phosphorus,its Resource Efficiency Should be Improved

The German government has adopted a law that requires sewage plants to go beyond the recovery of phosphorus from wastewater and to promote recycling. We argue that there is no physical global short‐ or mid‐term phosphorus scarcity. However, we also argue that there are legitimate reasons for policies such as those of Germany, including: precaution as a way to ensure future generations’ long‐term supply security, promotion of technologies for closed‐loop economics in a promising stage of technology development, and decrease in the current supply risk with a new resource pool.     

Self‐assembling amyloid‐like peptides as exogenous second harmonic probes for bioimaging applications

Amyloid‐like peptides are an ideal model for the mechanistic study of amyloidosis, which may lead to many human diseases, such as Alzheimer disease. This study reports a strong second harmonic generation (SHG) effect of amyloid‐like peptides, having a signal equivalent to or even higher than those of endogenous collagen fibers. Several amyloid‐like peptides (both synthetic and natural) were examined under SHG microscopy and shown they are SHG‐active. These peptides can also be observed inside cells (in vitro). This interesting property can make these amyloid‐like peptides second harmonic probes for bioimaging applications. Furthermore, SHG microscopy can provide a simple and label‐free approach to detect amyloidosis. Lattice corneal dystrophy was chosen as a model disease of amyloidosis. Morphological difference between normal and diseased human corneal biopsy samples can be easily recognized, proving that SHG can be a useful tool for disease diagnosis.     

生物衍生止血材料研究进展

生物来源的胶原蛋白、明胶、纤维蛋白原、纤维素、淀粉以及壳聚糖等材料,因为其无毒性、良好的生物相容性、生物可降解性以及促凝血活性越来越受到研究者的青睐,成为更加优异的止血选择。本文综述目前止血材料的几种类型及相应的止血机理,重点讨论上述生物来源止血材料的基本结构、止血机理、市售产品及最新科研进展,并对其发展前景进行展望。     

周围神经损伤后再生与修复机制研究进展

周围神经损伤是一种由于压迫、牵引、切割、缺血等原因引起的外周神经细胞损伤或坏死的疾病。周围神经损伤病理学变化包括轴浆运输受损、轴突变性、施万细胞损伤、节段性脱髓鞘和完全瓦勒氏变性。神经损伤后修复成为了现代医学研究中的热点与难点。本文对干细胞移植、神经营养因子、新型材料和生物电刺激在周围神经损伤修复中的作用及机制做了综述,并且对其在临床中的应用进行展望。     

口腔内金属材料对磁共振检查的影响

检测口腔内常用金属材料在磁共振检查时是否有伪影和伪影的严重程度。对２１种口腔内常用金属材料做了磁共振成像测试,磁共振仪磁场强度为１．５Ｔ,所用序列是梯度回波。铸金片、银汞合金、银尖等９种材料无伪影;钛合金和金属烤瓷成品有轻度伪影;牙用固位钉、椿钉等１０种材料有严重伪影。部分口腔内金属材料会引起严重伪影,影响图象质量,所以在做口腔颌面部和服部磁共振成像时,须引起重视。