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Semiconductor photocatalysis is an efficient technique to degrade the pollutants from wastewater. Herein, the doping of elements and the construction of heterojunctions are used to expand the visible light region and improve the transfer of photogenerated electrons-holes. The La-ZnO/BiOCl (LZB) heterojunction has been synthesized via the hydrothermal method. Furthermore, LZB-0.30 heterojunction is found to possess the optimal photodegradation efficiency of 100 % for RhB solution under the visible light within 45 min. Its degradation rate is ten times faster than that of La-ZnO, owing to positive development of photostimulated charge carriers. In addition, the results demonstrate that LZB-0.30, as an ideal photocatalyst, has great potential applications in the treatment of contaminants, providing a feasible strategy for environmental protection.

Abstract Social networks (SNs) have become popular as a medium for disseminating information and connecting like-minded people. They play a central role in decision-making by correlating the behaviors and preferences of connected agents. However, it is difficult to identify social influence effects in decision-making. In this article, we propose a framework of how to describe the uncertain nature of the social network group decision-making (SN-GDM) process. Social networks analysis (SNA) and quantum probability theory (QPT) are combined to construct a decision framework considering superposition and interference effects in SN-GDM scenarios. For the first time, we divide interference effects into symmetry and asymmetry. We construct an influence diagram, which is a quantum-like Bayesian network (QLBN), to model group decisions with interactions. We identify symmetry interference terms from Shapley value and asymmetry interference terms from trust value, respectively. The probability of an alternative is calculated through quantum probability theory in our influence diagram. The combination of QLBN model and social network could gain an understanding of how the group preferences evolve within SN-GDM scenarios, and provide new insights into SNA. Finally, an overall comparative analysis is performed with traditional SNA and other quantum decision models.

Coin and pouch cells are typically fabricated to assess the performance of new materials and components for lithium batteries. Here, parameters related to cell fabrication that influence the reliability of these measurements are discussed, including guidelines for reliable cell preparation.

Abstract Nowadays, metal oxide-based electromagnetic wave absorbing materials have aroused widely attentions in the application of telecommunication and electronics due to their selectable mechanical and outstanding dielectric properties. Herein, the binary ZnO/NiCo2O4 nanoparticles were successfully synthesized via hydrothermal reaction and the electromagnetic wave absorption properties of the composites were investigated in detail. As a result, benefiting from the dielectric loss, the as-obtained ZnO/NiCo2O4-7 samples possessed a minimum reflection loss value of −33.49 dB at 18.0 GHz with the thickness of 4.99 mm. This work indicates that ZnO/NiCo2O4 composites have the promising candidate applications in electromagnetic wave absorption materials in the future.

Urbanization has reduced river network connectivity, posing a great threat to water security. However, the mechanism through which changes in river network connectivity impact water security remains uncertain. River network connectivity and water security have been separately and thoroughly assessed by several researchers; however, few studies conducted a coupled assessment of these two aspects together, which may shed light on this mechanism. Based on assessment indicators developed in previous studies and key influence factors identified in the study area, this study proposed a comprehensive evaluation method to continually evaluate the adaptability between river network connectivity and water security in the Wuchengxiyu region, a highly urbanized area in Eastern China. The continuous evaluation was conducted for the period 2010–2019 based on the coupling coordination degree calculation formula. The results show that from 2010 to 2015, the coupling coordination degree between river network connectivity and water security followed a downward trend, due to the uncoordinated development between water systems and urbanization. After 2015, an increasing trend was observed with the implementation of environmental policies. In the past decade, the water surface rate and the coverage rate of suitable flow velocity decreased from 4.59% to 4.28% and from 54.1% to 30.9%, respectively, which may have negative effects on water quality and limit the improvement of regional flood control capacity. Moreover, the evaluation results also prove that policies such as the Ecological River–Lake Construction and the River Chief System have contributed to improve the quality of the water environment and regional flood control. The proposed assessment framework can be used as a guidance to evaluate the relationship between water network connectivity and water security; moreover, it provides new ideas for water network system protection and water quality maintenance in similar highly urbanized areas.

We clarify the degradation phenomena in a pouch cell that contains an insertion electrode (LizNi0.6Mn0.2Co0.2O2 or lithated NMC622) and a Li counter electrode. Greater than 500 cycles have been achieved in these cells employing 4 mAh/cm2 for both the initial Li metal negative and the NMC622 positive, and we find that cation mixing within the NMC622 is prevalent. That is, transition metals (Ni, and to a lesser extent, Mn and Co) in the transition-metal layer of NMC622 irreversibly exchange places with Li in the Li layer of NMC622, corresponding to a loss of Li sites and a concomitant loss of Coulombic capacity. The use of 1) a perturbation procedure of a recent publication employing the multi-site, multi-reaction model for the porous positive electrode and 2) a procedure to average the degradation phenomena over each cycle, which is shown to be consistent with slow degradation, simplifies the analysis of the experimental data and enables straightforward parameter regression. The resulting agreement between the model calculations and the experimental data is quite good, with the differences being similar to experiment-to-experiment variation.

In this report we detail a comprehensive study on the moisture stability of sulfide solid-state electrolytes in dry room environments. Although sulfide SSEs have many favorable attributes, this class of materials suffers from poor stability with water. Sulfide SSEs react with water to form gaseous H2S and a variety of solid byproducts like Li3PO4 and LiOH, which go on to increase the interfacial impedance of solid-state batteries. Lab-scale research typically utilizes gloveboxes with

Proton exchange membrane fuel cells often suffer from low lifetimes and high cost. Here, the authors enhance the transient power performance and durability of these fuel cells by integrating a thin layer of tungsten oxide within the anode, which acts as a hydrogen reservoir, oxygen scavenger, and a regulator for the hydrogen-disassociation reaction.

Cornus florida and Cornus hongkongensis subsp. elegans are potential species in saline-alkali areas for use as horticultural plants with high ornamental value. This work aimed to screen suitable tolerant dogwoods by comparing the responses of two dogwoods to salt stress according to phenotypic and physiochemical indicators on germination and seedling growth. For relieving seed dormancy, two pretreatments were performed on seeds, coded as T1 (soaked by gibberellic acid (GA3) alone) and T2 (soaked by GA3 with gradient salt concentrations of 0.2%, 0.3%, 0.4%, and 0.45%), and pretreated seeds were then germinated at the corresponding salt concentrations in pretreatment. As salt levels increased, the seed germination parameters decreased for both dogwoods, whereas the relative salt damage rate (SDR) significantly increased. While the growth of above-ground parts was significantly inhibited, that of underground parts changed little. Furthermore, the malondialdehyde content (MDA), superoxide dismutase activity (SOD), organic solutes (soluble sugar (SS) and proline (Pro)), and inorganic ions (K+, Na+, Ca2+) significantly accumulated in seedlings with increasing salinity levels, whereas K+/Na+ ratio decreased. Correlation analysis indicates that organic osmolyte (SS) and ion osmoregulation could be the main physiological mechanisms conferring salinity tolerance for both dogwoods. Compared with osmolytes, ion osmoregulation may be more critical for salt tolerance in the seedlings of the studied dogwoods. Collectively, the superior salt tolerance of C. florida to C. hongkongensis subsp. elegans suggests that the two species could be cultivated in saline areas with 0.3% and 0.2% salt levels, respectively.

Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is a commonly used decision model in multi-attribute group decision making (MAGDM), and a probabilistic linguistic term set (PLTS) is the linguistic variable that can effectively express the fuzziness of decision makers’ (DMs’) preference. However, in actual decision use, PLTS type decision preference needs to be processed before use, which can distort the decision results. The randomness of DM’s preference which also affects the final decision making is often ignored. Therefore, in order to better serve the MAGDM problem, this paper proposes an asymmetric probabilistic linguistic cloud TOPSIS (ASPLC-TOPSIS) method. First, the basic theories of linguistic variables and cloud model (CM) are introduced. Second, the conversation model between linguistic variables and CM is defined along with the operation formula of ASPLC. Third, considering the importance of the DMs’ subjective weights, a DM trust network is established to calculate the DMs’ weights. Finally, the decision process of ASPLC-TOPSIS is proposed and the superiority of this method is proved through experimental studies.

For high-energy lithium-sulfur batteries, a dense electrode with low porosity is desired to minimize electrolyte intake, parasitic weight, and cost. Here the authors show the impact of porosity on the performance of lithium-sulfur batteries and reveal the mechanism through analytical modeling.

Given the increasingly serious ozone pollution, petroleum refining has received more attention, since it is one of the dominant volatile organic compound-emitting industries in China. Volatile organic compound emission source identification, control efficiency classification, emissions calculation, emission factor generation and uncertainty analysis were performed in this study. According to the VOC emission control level, petroleum refining enterprises were divided into three levels, accounting for 10.6%, 54.4% and 35% of the total refining capacity, and 0.6%, 1.2%, and 3% were generated as the emission factor for each designed level, respectively. The total volatile organic compound emissions of the China petroleum refining industry in 2020 are estimated to be 1150 Kt by applying the hierarchical accounting method. Furthermore, the spatial distribution of volatile organic compound emissions was analyzed. The emission intensity of 15 cities is greater than the national average value of 0.12 tons/km2, where the highest level is approximately 2.7 tons/km2. To reduce the volatile organic compound emissions of PR enterprises, the collection efficiency and operation effect of treatment facilities are the most important points based on the analysis of the current situation of volatile organic compound emissions in the PR industry in China.

Quantum decision theory has been successfully applied to multi-attribute group decision-making (MAGDM) to model decision-makers’ interference and superposition effects in recent years. Existing quantum models assume that interference effects among decision-makers are symmetric. However, asymmetric interference effects have been ignored. We propose a VIKOR-based linguistic distribution assessments (LDAs) model considering asymmetric interference effects in a quantum decision scenario. Firstly, we combine VIKOR with LDAs to obtain a compromise solution in a fuzzy multi-attribute decision scenario with conflicting attributes. Secondly, an aggregation framework based on quantum probability theory is constructed to explore group preferences considering asymmetric interference effects among decision-makers. Finally, the model is compared with other methods to confirm its validity and stability.

In the traditional portfolio selection problem, asset returns are modeled as fuzzy variables with fuzzy return. However, this approach is limited in its ability to capture uncertainty accurately and in analytical model solving. Here, we aim to develop a new fuzzy chance-constrained portfolio model with a type-2 fuzzy return variable using a credibility measure. In real practice, an effective portfolio model under a new, more complex environment is required to improve instinctive imprecision. Here, we propose a novel analytical reduction method to transform our proposed model into a linear programing model with linear constraints, and use a linear programing tool to obtain optimal portfolio strategies. We first reformulate the portfolio model with type-2 fuzzy returns using two types of chance criteria. Next, we provide a new analytical method to solve the proposed model. Then, we present a numerical example with 20 asset returns described by a triangular membership function and use comparison testing to illustrate the advantages of our proposed method. The numerical results show that the relationship between investor tolerance of portfolio risk and the values attained for the four objective functions is in line with our expectations regarding the risk–return trade-off, and the comparison test results indicate that our proposed reduction method performs better than three existing methods. Our method provides an effective practice model for reformulating type-2 fuzzy portfolio problems using an analytical reduction method. Although a large number of existing type-2 fuzzy portfolio problems cannot be solved by our analytical method, it represents a new tool to solve these kinds of problems.

With the development of social networking big data, social network group decision-making (SN-GDM) has been widely applied in many fields. This paper focuses on three main components: (1) the determination of the decision makers' (DMs) weights based on different social influence; (2) the anti-deception mechanism; and (3) the persona method. We introduce the TrustRank algorithm and the persona method into SN-GDM. Based on the TrustRank algorithm, both trusted and deceptive DMs in a seed set are artificially identified and given initial static scores to derive the influence of each DM. Additionally, the persona method is introduced to cluster DMs and achieve personalized decision-making. Further, we present a numerical example and comparison to demonstrate the efficiency of the framework in coping with non-socially shared preferences in SN-GDM. As expected, our findings indicate that our framework reduces the influence of deceptive DMs on the decision results.

The linguistic approaches are required in order to assess qualitative aspects of many real problems. In most of these problems, decision makers only adopt single and very simple terms which would not reflect exactly what the experts mean for many intricate applications. Frequently, the assessments of decision making problems involve comparative linguistic expressions. Accordingly, we propose a novel distance measure between hesitant fuzzy linguistic term sets (HFLTSs) to solve fuzzy group decision making (FGDM) problems. Firstly we define the characteristic functions to describe the HFLTSs transformed from comparative linguistic expressions. Then we construct a weighted HFLTSs graph containing all notes in the HFLTSs. Distances in the graph of individual assessments are defined by measures considering diversity and specificity of HFLTS's granularity. We put forward a new approach to achieve aggregation results for group decision making to realize the minimal distances with individual assessments. Finally, numerical examples are illustrated.

Currently, recommender systems (RS) are incorporating implicit information from social circle of the Internet. The implicit social information in human mind is not easy to reflect in appropriate decision making techniques. This paper consists of 2 contributions. First, we develop an item-based prototype classifier (IPC) in which a prototype represents a social circle’s preferences as a pattern classification technique. We assume the social circle which distinguishes with others by the items their members like. The prototype structure of the classifier is defined by two2-dimensional matrices. We use information gain and OWA aggregator to construct a feature space. The item-based classifier assigns a new item to some prototypes with different prototypicalities. We reform a typical data set—Iris data set in UCI Machine Learning Repository to verify our fuzzy prototype classifier. The second proposition of this paper is to give the application of IPC in recommender system to solve new item cold-start problems. We modify the dataset of MovieLens to perform experimental demonstrations of the proposed ideas.

On-board hydrogen storage is an important obstacle to the development of a sustainable, ultra-low emission transportation system. A dry particle coating technique was used to coat micron-sized magnesium powders with Ni nanoparticles for hydrogen storage. Three parameters were explored in this study: powder size, nickel loading, and processing time. The composite materials were evaluated based upon a number of criteria, including the degree to which the nanoparticles were distributed over the Mg surface, the improvement in kinetics for hydrogen absorption, and the increased amount of hydrogen absorbed and desorbed. Comparisons were made between the bulk Mg powders and those coated with Ni. Due to the high shear forces it created, the dry particle coating system effectively distributed Ni nanoparticles onto the Mg powder surface. A coating process that required 48 hours using traditional ball milling was reduced to 90 minutes with the dry particle coating system. Magnesium powder with a mean diameter of 44 microns and a nickel loading of 2 atomic weight percent was the most kinetically active for hydrogen absorption under the conditions studied. Hydrogen absorption began at 150°C, and desorption started at 250°C. The dry particle coating system, however, did not alter the magnesium microstructure during 90 minutes of processing and did not produce the large surface areas generated by ball milling.

The current materials used in proton exchange membrane fuel cells (PEMFCs) are not sufficiently durable for commercial deployment. One of the major challenges lies in the development of an inexpensive, efficient, and highly durable and active electrocatalyst. Here a new type of carbon-free Pt/Nb-TiO2 electrocatalyst has been reported. Mesoporous Nb-TiO2 hollow spheres were synthesized by the sol-gel method using polystyrene (PS) sphere templates. Pt nanoparticles (NPs) were then deposited onto mesoporous Nb-TiO2 hollow spheres via a simple wet-chemical route in aqueous solution, without the need for surfactants or potentiostats. The growth densities of Pt NPs on Nb-TiO2 supports could be easily modulated by simply adjusting the experimental parameters. Electrochemical studies of Pt/Nb-TiO2 show much enhanced activity and stability than commercial E-TEK Pt/C catalyst. PtNP/Nb-TiO2 is a promising new cathode catalyst for PEMFC applications.

Cr3+-activated near-infrared (NIR) phosphors are key for NIR phosphor-converted light emitting diodes (NIR pc-LED). While, the site occupancy of Cr3+ is one of the debates that have plagued researchers. Herein, Y2Mg2Al2- Si2O12 (YMAS) with multiple cationic sites is chosen as host of Cr3+ to synthesize YMAS: xCr3+ phosphors. In YMAS, Cr3+ ions occupy simultaneously Al/SiO4 tetrahedral, Mg/AlO6 octahedral, and Y/MgO8 dodecahedral sites which form three luminescent centers named as Cr1, Cr2, and Cr3, respectively. Cr1 and Cr2 relate to an intermediate crystal field, with transitions of ²E→4A2 and 4T2→4A2 occurring simultaneously. As Cr3+ concentration increases, the 4T2→4A2 transition becomes more pronounced in Cr1 and Cr2, resulting in a red-shift and broadband emission. Cr3 consistently behaves a weak crystal field and exhibits the broad and long-wavelength emission. Wide-range NIR emission centering at 745 nm is realized in YMAS: 0.03Cr3+ phosphor. This phosphor has high internal quantum efficiency (IQE = 86%) and satisfying luminescence thermal stability (I423 K = 70.2%). Using this phosphor, NIR pc-LEDs with 56.6 mW@320 mA optical output power is packaged and applied. Present study not only demonstrates the Cr3+ multi-site occupancy in a certain oxide but also provides a reliable approach via choosing a host with diverse cationic sites and local environments for Cr3+ to achieve broadband NIR phosphors. [ABSTRACT FROM AUTHOR]

A rare subtype of diffuse large B-cell lymphoma (DLBCL) has been reported to be accompanied by elevated immunoglobulin M (IgM) paraprotein in the serum at diagnosis, called as IgMs-DLBCL. The monoclonal IgM paraprotein disappears soon after treatment in most of these patients. Here, we described a DLBCL patient with continuously elevated IgM following therapy. A 59-year-old male was diagnosed with DLBCL (GCB subtype per Hans algorithm, stage IA) with involvement of the right cervical lymph node. After six cycles of immunochemotherapy with the R-CHOP regimen, complete metabolic remission was achieved, but an elevated level of serum IgM persisted. To investigate the origin of elevated IgM, pathologic, immunophenotypic, and molecular analyses of lymph node and bone marrow (BM) samples were performed pre- and post-treatment. BM infiltration of lymphoplasmacytic cells, and a typical immunophenotypic profile by flow cytometry supported the diagnosis of Waldenström macroglobulinemia (WM). The MCD subtype of DLBCL was identified by next-generation sequencing of the lymph node at initial diagnosis characterized by cooccurring point mutations in MYD88L265P and CD79B. Additionally, two different dominant clonotypes of the immunoglobulin heavy chain (IGH) were detected in the lymph node and BM by IGH sequencing, which was IGHV 3--11*06/IGHJ 3*02 and IGHV 3--11*06/IGHJ 6*02, respectively, speculating to be two independent clonal origins. This study will provide a panoramic understanding of the origin or biological characteristics of DLBCL co-occurring with WM. [ABSTRACT FROM AUTHOR]