With the ever‐growing diversity of devices and applications that will be connected to 5G networks, flexible and agile service orchestration with acknowledged quality of experience (QoE) that satisfies the end user's functional and quality‐of‐service (QoS) requirements is necessary. Software‐defined networking (SDN) and network function virtualization (NFV) are considered key enabling technologies for 5G core networks. In this regard, this paper proposes a reinforcement learning–based QoS/QoE‐aware service function chaining (SFC) scheme in SDN/NFV‐enabled 5G slices. First, it implements a lightweight QoS information collector based on the Link Layer Discovery Protocol, which works in a piggyback fashion on the southbound interface of the SDN controller, to enable QoS‐awareness. Then, a deep Q‐network–based orchestration agent is designed to support SFC in the context of NFV. The agent takes into account the QoE and QoS as key aspects to formulate the reward so that it is expected to maximize QoE while respecting QoS constraints. The experiment results show that the proposed framework exhibits good performance in QoE provisioning and QoS requirements maintenance for SFC in dynamic network environments.

The lignin‐first concept is a new innovation for full utilization of lignocellulose into value‐added chemicals. Ionic liquid (IL) polyoxometalates [MIMPS]2H4P2Mo18O62 [MIMPS=1‐(3‐sulfonic group) propyl‐3‐methyl imidazolium] are reported to be active in the cleavage of β‐O‐4, α‐O‐4, and 4‐O‐5 bonds in three kinds of lignin models and also efficient for converting native lignocellulose. The three components in soft or hard lignocellulose were depolymerized in a one‐pot three‐step treatment. For soft lignocellulose (pine), lignin was first decomposed into guaiacol and phenol with yields of 15.3 and 12.9 % at 98.6 % delignification efficiency at 130 °C for 14 h. Meanwhile, hemicellulose and cellulose were intact during the delignifying process and were subsequently hydrolyzed to 3.5 % xylose at 100 % hemicellulose conversion efficiency at 150 °C for 14 h and 36.4 % glucose at 100 % cellulose conversion efficiency at 170 °C for 12 h, respectively. For hard lignocellulose (poplar), the yields of guaiacol and phenol were 10.1 and 8.7 % at 91.9 % delignification efficiency at 130 °C for 14 h, whereas 12.9 % xylose at 90.4 % hemicellulose conversion efficiency at 150 °C for 12 h and 32.9 % glucose at 100 % cellulose conversion efficiency at 170 °C for 12 h were obtained. [MIMPS]2H4P2Mo18O62 achieved the full utilization of lignocellulose with total conversion in the lignin‐first strategy and also showed the easy separation as a result of temperature‐reversibility with ten recycling runs.

Terrestrialization is one of the most momentous events in the history of plant life, which leads to the subsequent evolution of plant diversity. The transition species, in this process, had to acquire a range of adaptive mechanisms to cope with the harsh features of terrestrial environments compared to that of aquatic habitat. As an ancient antioxidant, a leading regulator of ROS signaling or homeostasis, and a presumed plant master regulator, melatonin likely assisted plants transition to land and their adaption to terrestrial ecosystems. N‐acetylserotonin methyltransferases (ASMT) and caffeic acid O‐methyltransferases (COMT), both in the O‐methyltransferase (OMT) family, catalyze the core O‐methylation reaction in melatonin biosynthesis. How these two enzymes with close relevance evolved in plant evolutionary history and whether they participated in plant terrestrialization remains unknown. Using combined phylogenetic evidence and protein structure analysis, it is revealed that COMT likely evolved from ASMT by gene duplication and subsequent divergence. Newly emergent COMT gained a significantly higher ASMT activity to produce greater amounts of melatonin for immobile plants to acclimate to the stressful land environments after evolving from the more environmentally‐stable aquatic conditions. The COMT genes possess more conserved substrate‐binding sites at the amino acid level and more open protein conformation compared to ASMT, and getting a new function to catalyze the lignin biosynthesis. This development directly contributed to the dominance of vascular plants among the Earth's flora and prompted plant colonization of land. Thus, ASMT, together with its descendant COMT, might play key roles in plant transition to land. The current study provides new insights into plant terrestrialization with gene duplication contributing to this process along with well‐known horizontal gene transfer.

Selective breakage of the β-O-4 bond in lignin is the key procedure for full conversion of lignocellulose; however, non-noble metal-based catalysts usually require harsh reaction conditions in the cleavage of the β-O-4 bond and show low selectivity in heterogeneous catalysis. Despite the tremendous development in recent years, it still remains a great challenge to develop versatile catalysts with high efficiency, convenient regeneration, and multifunctionality to achieve full lignocellulose valorization. Herein, a strategy of “atom-by-atom” replacement of the central atom (P5+ by V5+) was employed to obtain the polyoxometalate (POM) catalyst, H6V2Mo18O62 (H6V2Mo18), which exhibited a significantly enhanced activity on the cleavage of β-O-4 lignin models (compared to the original H6P2Mo18O62). The optimized electronegativity of Mo and O atoms induced by the inserted vanadium at the central site and the modified acidic/redox ability of H6V2Mo18 had been extensively analyzed by density functional theory (DFT) and experiment. Deep eutectic solvent cation betaine (Bet+) was further used to solidify H6V2Mo18 to obtain the BetH5V2Mo18, which acted as a trinitarian catalyst with controlled acidic/redox ability and thermosensitive ability for mass-transferring confirmed by molecular dynamics simulations, DFT, and experiments. Using BetH5V2Mo18 as a highly efficient catalyst, full utilization of lignocellulose can be easily achieved with the one-pot method via temperature-programmed treatment. This work is opening new research frontiers in the design of multifunctional-site POMs with a specialized micro-environment in biomass valorization, and this new trinitarian catalyst could lead to a new trend in catalyst design.

The direct conversion of cellulose to glycolic acid (GA) with a high yield of up to 75% is realized using acidic/redox polyoxometalates (POMs) as catalysts in a one-pot reaction. Analysis of the reaction pathway and mechanism for the three POMs H3PMo12O40 (H3PMo), H3PW12O40 (H3PW), and H5PMo10V2O40 (H5PMoV2) by density functional theory calculations and experiments shows that H3PMo is especially promising. Activation of O2 to •O2 – and 1O2 via one-electron transfer assists the depolymerization process of cellulose by acidic/redox H3PMo. The reduced form [PMo10 VIMo2 VO39]5– plays a crucial role in GA production due to its high activity and ability to stabilize the intermediates of the retro-aldol reaction. H3PMo was furthermore complexed by the ionic liquid 1-(3-sulfonic group) propyl-3-methyl imidazolium (MIMPS), which enables easy recovery from the reaction solution due to temperature-responsive properties of the complexes. [MIMPS]H2PMo provides an outstanding GA selectivity of 61% under aerobic conditions and is comparable to the homogeneous H3PMo. Activity and selectivity to GA could be improved to 100 and 75%, respectively, by performing the reaction in the microwave at 190 °C for 2 min. The work deepens the insight on cellulosic biomass transformation over POMs by acidic/oxidative synergetic catalysis and contributes to the effort of designing highly active, selective, and multifunctional catalysts.

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Peroxidation of glycerol has been carried out in a polyoxometalate (POM)‐based microfluidic reactor, which was fabricated on a capillary by using a layer‐by‐layer strategy. Lactic acid (LA) is produced selectively in high yield with a TOF as high as 20 000 h−1, compared to a TOF of 200 h−1 in batch mode. This POM microfluidic reactor is readily prepared, scalable, highly stable, reusable, and also potentially applicable to selective oxidation of other bio‐wastes.

Intelligence-Generated Content (AIGC) refers to the use of AI to automate the information creation process while fulfilling the personalized requirements of users. However, due to the instability of AIGC models, e.g., the stochastic nature of diffusion models, the quality and accuracy of the generated content can vary significantly. In wireless edge networks, the transmission of incorrectly generated content may unnecessarily consume network resources. Thus, a dynamic AIGC service provider (ASP) selection scheme is required to enable users to connect to the most suited ASP, improving the users' satisfaction and quality of generated content. In this article, we first review the AIGC techniques and their applications in wireless networks. We then present the AIGC-asa-service (AaaS) concept and discuss the challenges in deploying AaaS at the edge networks. Yet, it is essential to have performance metrics to evaluate the accuracy of AIGC services. Thus, we introduce several image-based perceived quality evaluation metrics. Then, we propose a general and effective model to illustrate the relationship between computational resources and user-perceived quality evaluation metrics. To achieve efficient AaaS and maximize the quality of generated content in wireless edge networks, we propose a deep reinforcement learning-enabled algorithm for the optimal ASP selection. Simulation results show that the proposed algorithm can provide a higher quality of generated content to users and achieve fewer crashed tasks by comparing with four benchmarks, i.e., overloading-avoidance, random, round-robin policies, and the upper-bound schemes.