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We investigated the feasibility of using surface-enhanced Raman scattering (SERS) technology combined with the AdaBoost algorithm to rapidly discriminate cervical cancer patients from hysteromyoma patients. Using Au colloids as the SERS active substrate, we recorded Raman signal measurements on serum RNA samples obtained from 35 patients diagnosed with cervical cancer and 30 patients diagnosed with hysteromyoma. Analysis of RNA SERS spectra using principal component analysis, then three principal components (PC2, PC11, and PC24) with significant differences were chosen using the independent samples t-test (p < 0.05). The distinctive peak intensities of the relevant substance, measured at 448, 519, 698, 1003, and 1076 cm–1, were found to be correlated with the substance's alterations during the carcinogenesis process. The ideal AdaBoost classification model was developed by fi ne-tuning its parameters. The model showcased an impressive accuracy of 96.92%, exhibiting a high sensitivity of 94.28% and an exceptional specificity of 100%, as reported in the results. Compared to the linear discriminant analysis, support vector machine models, the effectiveness of classification greatly improved. The current findings indicate that serum SERS technology, combined with the AdaBoost algorithm, is anticipated to be developed into a potent screening tool for cervical cancer. [ABSTRACT FROM AUTHOR]

MnZn ferrites that exhibit low core losses at high frequencies are suitable for the integration and miniaturization of power conversion devices. To obtain low core losses at high frequencies, it is important to understand the underlying mechanism. In this work, MnZn ferrites with various grain sizes were produced by changing the sintering temperature. The relationship between domain morphology, dynamic magnetization behavior, and core losses at high frequencies was carefully investigated. As the average grain size approached the critical size of single‐domain state, the contribution of domain wall displacement to complex permeability decreased, while domain wall resonant frequency improved significantly, resulting in the suppression of residual loss at 3 MHz. As the average grain size increased, the domain morphology changed from a single‐domain state to a multidomain state, which increased the initial permeability and decreased hysteresis loss. However, the number of domain walls increased, causing a significant decrease in the domain wall resonant frequency, and resulting in a sharp increase in residual loss. These results provide valuable insights into reducing high‐frequency core losses in MnZn ferrites by domain engineering. [ABSTRACT FROM AUTHOR]

Owing to their biocompatibility, chemical stability, film-forming ability, cost-effectiveness, and excellent electroactive properties, poly(vinylidene fluoride) (PVDF) and PVDF-based polymers are widely used in sensors, actuators, energy harvesters, etc. In this review, the recent research progress on the PVDF phase structures and identification of different phases is outlined. Several approaches for obtaining the electroactive phase of PVDF and preparing PVDF-based nanocomposites are described. Furthermore, the potential applications of these materials in wearable sensors and human energy harvesters are discussed. Finally, some challenges and perspectives for improving the properties and boosting the applications of these materials are presented. [ABSTRACT FROM AUTHOR]

Alanine transaminase (ALT) is an important amino acid-metabolizing enzyme in silkworm Bombyx mori L., and is mainly involved in transferring glutamate to alanine (serving as an essential precursor in silk protein synthesis) through transamination. Therefore, it is generally believed that silk protein synthesis in the silk gland and the cocoon quantity increase with the increase in ALT activity to a certain extent. Here, a novel analytical method was developed to determine the ALT activity in several key tissues of Bombyx mori L. including the posterior silk gland, midgut, fat body, middle silk gland, trachea and hemolymph, by combining the direct-analysis-in-real-time (DART) ion source with a triple-quadrupole mass spectrometer. In addition, a traditional ALT activity assay, the Reitman–Frankel method, was also used to measure ALT activity for comparison. The ALT activity results obtained via the DART-MS method are in good agreement with those obtained via the Reitman–Frankel method. However, the present DART-MS method provides a more convenient, rapid and environmentally friendly quantitative method for ALT measurement. Especially, this method can also monitor ALT activity in different tissues of Bombyx mori L. in real time. [ABSTRACT FROM AUTHOR]

To achieve compact and lightweight power conversion devices, magnetic core materials such as MnZn ferrite are highly desired with low core losses at high frequencies above megahertz. In this work, high-valent Sn4+ ions were doped into MnZn ferrite to manipulate the electromagnetic properties and suppress the high-frequency core losses. The distribution of Sn4+ in MnZn ferrite was investigated by transmission electron microscopy with energy dispersive x-ray analysis, which indicated that most of the substituted Sn4+ ions remained at the grain boundaries rather than dissolving into the lattice, and thus greatly impacted the electromagnetic properties of MnZn ferrite. The initial permeability and saturation induction decreased monotonically with the Sn substitution. The core loss was reduced to 457 kW m−3 at 3 MHz, 30 mT, and 25 °C when the Sn substitution content was 0.003, due to the effective suppression of eddy current loss and residual loss. The sample with a Sn content of 0.003 exhibited excellent overall electromagnetic properties, which could be potentially useful in high-frequency transformers, converters, and power sources. [ABSTRACT FROM AUTHOR]

Malayaite (CaSnSiO5) doped with Cr may be used as a cheap gold‐free purple red pigment to substitute the purple of Cassius. Different molar ratios of Ca/Sn malayaite doped with Cr were prepared and various characrizations were employed. The results indicate that the pigment is composed of CaSnSiO5 and SnO2 when the molar ratio of Ca/Sn is 0.8, and the color is close to agate red color. When the molar ratio of Ca/Sn is 1.25, the phases CaSnSiO5, SnO2, and Ca3SnSi2O9 exist simultaneously, while the color is yellow or yellowish colors. Excessive Ca(II) increases the normal calcination temperature of pigment, from 1080°C to 1130°C. The distribution of chromium ions on the sample surface varies greatly with the change in Ca/Sn molar ratio. The theoretical formulation was obtained based on the stoichiometric formula of CaCrxSn1–xSiO5 by using response surface methodology (RSM). According to the RSM model, the relationship between the molar ratio of Cr/Sn/Ca and the color property was established. The desired pigment formulation (rendering agate red) color is that the molar ratio of Cr/Sn/Ca is 0.010:1.003:0.800. The accuracy of the models was confirmed with analysis of variance, the simulation results were verified again by experiments. [ABSTRACT FROM AUTHOR]

Amidinium salts have been utilized in perovskite precursor solutions as additives to improve the quality of perovskite films. The design of hydrophilic or hydrophobic groups in amidinium salts is of great importance to photovoltaic device performance and stability in particular. Here we report a contrast study of a guanidinium iodide (GUI) additive with a hydrophilic NH2 group, and a N,1–diiodoformamidine (DIFA) additive with a hydrophobic C–I group, to investigate the group effect. The addition of GUI or DIFA was beneficial to achieve high quality perovskite film and superior photovoltaic device performance. Compared with GUI, the addition of the DIFA in a perovskite precursor solution enhanced the crystal quality, reduced the defect density, and protected the water penetration into perovskite film. The perovskite solar cell (PSC) devices showed the best power conversion efficiency (PCE) of 21.19% for those modified with DIFA, as compared to 18.85% for the control, and 20.85% for those modified with GUI. In benefit to the hydrophobic C–I group, the DIFA–modified perovskite films and PSC exhibited the best light stability, thermal stability, and humidity stability in comparison to the control films and GUI–modified films. Overall, the introduction of a hydrophobic group in the amidinium salts additive was demonstrated to be an efficient approach to achieve high quality and stable perovskite film and PSC devices. [ABSTRACT FROM AUTHOR]

Satellite observation scheduling plays a significant role in improving the efficiency of Earth observation systems. To solve the large-scale multisatellite observation scheduling problem, this article proposes an ensemble of metaheuristic and exact algorithms based on a divide-and-conquer framework (EHE-DCF), including a task allocation phase and a task scheduling phase. In the task allocation phase, each task is allocated to a proper orbit based on a metaheuristic incorporated with a probabilistic selection and a tabu mechanism derived from ant colony optimization and tabu search, respectively. In the task scheduling phase, we construct a task scheduling model for every single orbit and solve the model by using an exact method (i.e., branch and bound, B&B). The task allocation and task scheduling phases are performed iteratively to obtain a promising solution. To validate the performance of the EHE-DCF, we compare it with B&B, three divide-and-conquer-based metaheuristics, and a state-of-the-art metaheuristic. Experimental results show that the EHE-DCF can obtain higher scheduling profits and complete more tasks compared with existing algorithms. The EHE-DCF is especially efficient for large-scale satellite observation scheduling problems. [ABSTRACT FROM AUTHOR]

Using the high incompatibility between the neutral stabilizer body and the block polyelectrolyte to drive phase separation during polymerization-induced self-assembly, a modular approach to systematically adjust ionic monomer/polymer solubility was developed to effectively identify monomers suitable for RAFT aqueous dispersion polymerization, with strong phase separation ability to form worm phases over a wide range of compositions and even at very low solid content. The block copolymer PMPS-MPS-P([META+][PF6−]), prepared by this method, acts as a "nano bridge" and achieves Ni loading on TiO2 with the help of the sol–gel method + thermal reduction. The atomic loading of Ni on TiO2 is achieved through strong covalent bonding, metallic bonding and the natural physical intertwining effect of the silane coupling agent. Interestingly, it was unexpectedly found that the TiC stable structure generated by this process, the ionization of part of the block polyelectrolyte after the thermal reduction treatment at 773 K and the loading process of Ni all can promote the formation of oxygen vacancy Ov, which facilitates the charge transfer and hydrogen precipitation reaction. It has superior photocatalytic ability and cheaper cost compared to the conventional impregnation dispersion method. These findings provide a new idea to modify the manipulated photocatalysts by defect engineering to achieve efficient photocatalytic efficiency and capability. [ABSTRACT FROM AUTHOR]

A \Pi ^{0}_{1} class P is thin if every \Pi ^{0}_{1} subclass Q of P is the intersection of P with some clopen set. In 1993, Cenzer, Downey, Jockusch and Shore initiated the study of Turing degrees of members of thin \Pi ^{0}_{1} classes, and proved that degrees containing no members of thin \Pi ^{0}_{1} classes can be recursively enumerable, and can be minimal degree below \mathbf {0}'. In this paper, we work on this topic in terms of genericity, and prove that all 2-generic degrees contain no members of thin \Pi ^{0}_{1} classes. In contrast to this, we show that all 1-generic degrees below \mathbf {0}' contain members of thin \Pi ^{0}_{1} classes. [ABSTRACT FROM AUTHOR]

Through urban traffic patrols, problems such as traffic congestion and accidents can be found and dealt with in time to maintain the stability of the urban traffic system. The most common way to patrol is using ground vehicles, which may be inflexible and inefficient. The vehicle–drone coordination maximizes utilizing the flexibility of drones and addresses their limited battery capacity issue. This paper studied a vehicle–drone arc routing problem (VD-ARP), consisting of one vehicle and multiple drones. Considering the coordination mode and constraints of the vehicle–drone system, a mathematical model of VD-ARP that minimized the total patrol time was constructed. To solve this problem, an improved, adaptive, large neighborhood search algorithm (IALNS) was proposed. First, the initial route planning scheme was generated by the heuristic rule of "Drone-First, Vehicle-Then". Then, several problem-based neighborhood search strategies were embedded into the improved, adaptive, large neighborhood search framework to improve the quality of the solution. The superiority of IALNS is verified by numerical experiments on instances with different scales. Several critical factors were tested to determine the effects of coordinated traffic patrol; an example based on a real road network verifies the feasibility and applicability of the algorithm. [ABSTRACT FROM AUTHOR]

The task-schedulingalgorithm is a key module to satisfy various complex user requirements, and improve the usage flexibility and efficiency of data relay satellites networks (DRSN). In this context, we first propose a novel application mode for DRSN, in which users are allowed to submit multiple optional service time windows and specify a preferred antenna as well as an expected execution duration for each task. Meanwhile, the start time of a service time window can be adjusted within a specified range. A mathematical programming model that maximizes the completion ratio of tasks and the expectation satisfaction of users is established. Moreover, a conflict resolution-assisted iterative task-scheduling algorithm (CRITS) is designed, composing of five closely dependent operators: resource matching, service durations generation, conflict evaluation, conflict resolution, and solution update. To verify the effectiveness of the proposed CRITS, extensive experiments are carried out. The experimental results demonstrate the competitive performance of CRITS in addressing the DRSN scheduling problem. In comparison with two heuristic algorithms (heuristic algorithm based on time-freedom degree and a heuristic algorithm based on task priority) and a meta-heuristic algorithm (adaptive variable neighborhood descent combined with a tabu list), the proposed CRITS increases the overall completion ratio of tasks by 6.65, 10.26, and 10.96%, respectively. [ABSTRACT FROM AUTHOR]

Potential industrial applications of high-performance cast Al−Li−Cu−(Mg) alloys micro-alloyed with Sc have been strongly limited due to the extremely high production cost and scarcity of Sc. This work aimed at evaluating the effect of substituting Yb for Sc on the microstructure characteristics, age-hardening response and mechanical performances of cast Al−2Li−2Cu−0.5 Mg−0.2Zr alloy. Varied Yb additions were tried (0%, 0.1wt%, 0.2wt%) and results indicated that no appreciable grain refinement was achieved in alloys modified with Yb, accompanied with the absence of coarse primary phases. Dissolution of Cu-rich secondary phases during solution treatment was markedly retarded as the Yb addition increased to 0.2wt%. Nucleation of Al3Li on Al3(Yb, Zr) led to the significant reduction in the strain energy change (ΔGS) and interfacial energy. The addition of 0.1wt% Yb resulted in the accelerated age-hardening response and promoted precipitation of L12-structured nanometric core–shell Al3Li/Al3(Yb, Zr) precipitates, which acted as preferential nucleation sites for T1 and S′ phases. As a result, a better mechanical characteristics and microstructural stability was obtained in alloy with 0.1Yb addition compared with the base alloy. Moreover, as compared to the Sc-modified alloy, a small reduction in mechanical properties was achieved in 0.1Yb alloy accompanied with significant reduction in production cost, revealing the feasibility of substituting Yb for Sc. [ABSTRACT FROM AUTHOR]

Early disease screening is of great significance to its prevention and treatment, and serum analysis is one of the important methods for early disease screening. In this paper, a portable spectrometer was used to collect serum Raman spectra of echinococcosis patients and healthy volunteers, and a one‐dimensional convolutional neural network (CNN) was used to classify the two types of spectra. The average spectrum shows that the phenylalanine and carotene content in the serum of patients with echinococcosis is less than that in healthy volunteers, whereas the content of amino acids such as proline and tyrosine is higher. We built a CNN model to identify two types of spectra. First, the Kennard–Stone algorithm was used to divide the two types of spectra into a training set and a test set. Afterwards, the optimal hyperparameters of the model were determined by fivefold cross‐validation on the training set. Finally, the test set was used to evaluate the final effect of the model. The accuracy, sensitivity, and specificity of the test set on the model are 94.90%, 90.57%, and 97.11%, respectively. The receiver operating characteristic curve analysis further confirmed the excellent performance of the CNN in the classification of serum Raman spectra. The above results show that serum Raman spectroscopy combined with a one‐dimensional CNN algorithm has great potential in the early diagnosis of echinococcosis. [ABSTRACT FROM AUTHOR]

Recently, driven by advancements in the payload capacity and endurance of drones, the logistics industry has shown significant interest in drone Last-Mile logistics. Efficient routing are crucial scientific challenges in drone delivery problems. In this study, we address the routing problem in heterogeneous drone delivery, which involves a large drone transporting multiple small drones to sub-regions for parcel delivery, aiming to both reduce the drones' distance costs and improve customer satisfaction, termed HDDPBO To tackle the HDDPBO problem effectively, we propose a voting-based ensemble multi-objective genetic approach, named VEMOGA, in which an improved clustering algorithm is developed to divide customers into K clusters, enabling each drone to handle multiple parcel deliveries within a sub-region. In this way, it reduces the complexity of HDDPBO by transforming it into multiple sub-problems. Secondly, a multi-objective genetic approach with heuristic operators is proposed to explore high-quality solutions, in which customized crossover and mutation operators are designed in the genetic approach, and a voting-based ensemble algorithm is designed to robustly select the Pareto frontier with high-quality convergence and diversity. Extensive experiments are conducted on synthetic instances to evaluate the proposed algorithm, and the experimental results demonstrate superior performance compared to three other baselines. Additionally, a real-world instance has been scrutinized to ascertain the applicability of Last-Mile logistics, and sensitivity analyses of pivotal factors have been conducted and several managerial insights pertinent are given to the drone-based Last-Mile logistics. • A multi-objective model is proposed for heterogeneous drone logistics. • A voting-based ensemble multi-objective genetic algorithm is proposed. • The proposed algorithm achieves higher satisfaction and lower costs. [ABSTRACT FROM AUTHOR]

• Mechanical properties of Al-Cu-Li alloy were enhanced via optimizing Ag/Mg ratios. • The variation of Ag/Mg ratios modifies the precipitation sequence of the alloy. • High relative volume fraction and large size of T 1 phases lead to improved strength. • The coexistence of T 1 , θ́, and Ś phases contributes to high ductility. Wrought Al-Cu-Li alloys usually necessitate pre-stretching to improve their mechanical properties. A novel insight into enhancing the mechanical properties of a non-stretched Al-Cu-Li alloy has been proposed by optimizing the Ag/Mg ratios and investigating their impact on precipitation behavior. Four alloys having Ag/Mg ratio between 0.24–5.63 and a combined Ag + Mg content of 1.1 wt% were designed. The results indicated that the strengthening precipitates were mainly plate-like T 1 and θ́ precipitates. With decreasing Ag/Mg ratios from 5.63 to 1.87, T 1 phase fraction increased from 28 % to 39 %, and the corresponding θ́ phase fraction reduced from 72 % to 61 %. Comparatively, S' phases dominated the microstructure while impeding the formation of θ' and T 1 precipitates at Ag/Mg ratio was 0.24. The alloy at Ag/Mg ratio of 0.95 had optimum mechanical properties owing to T 1 , Ś, and θ́ phases uniform dispersion within the matrix, among which T 1 had the highest volume fraction (48 %). [ABSTRACT FROM AUTHOR]

[Display omitted] • Low-temperature pre-ageing combined with pre-stretching enhances the strength–ductility synergy of extruded Al-Cu-Li alloys. • The yield strength and elongation of the Al-3.7Cu-1Li-0.40Mg-0.75Ag alloy increase by 4.4 % and 60.3 %, respectively. • Pre-ageing at 110 °C leads to the formation of a large number of thermodynamically stable GP zones within the matrix. • GP zones regulate dislocation configuration and precipitation behavior, contributing to an improvement in elongation. Balancing strength and ductility proves challenging in high-strength wrought Al-Cu-Li alloys, particularly in extruded rods. The abundance of subgrain structures hinders dislocation movement, inevitably sacrificing the ductility. Herein, an effective strategy for enhancing the strength-ductility synergy in an extruded Al-3.7Cu-1Li-0.40Mg-0.75Ag alloy was reported by developing a novel combinatorial pretreatment (CPT), including pre-ageing after solution treatment, followed by pre-stretching. Subsequently, the CPT alloys undergo artificial ageing at 150 °C. Desirable comprehensive mechanical properties (YS = 668 MPa, UTS = 700 MPa, and EL = 12.5 %) were obtained through pre-ageing at 110 °C before 4 % pre-stretching. Notably, the elongation showed a remarkable improvement of 60.3 % compared to the non-CPT sample, without sacrificing the yield strength. Microstructure analysis indicates that the interactions between the GP zones and dislocations facilitated energy dissipation during pre-stretching, effectively mitigating local stress concentration. Consequently, promoted ductility was realized through a more uniform dislocation distribution. Furthermore, the dense GP zones formed during pre-ageing served as the heterogeneous nucleation sites for precipitates, increasing the volume fraction of θ′ phases. This adjustment in dislocation motion further contributed to ductility improvements. Our approach offers new insights into developing high-performance extruded Al-Cu-Li alloys with both high strength and desirable ductility. [ABSTRACT FROM AUTHOR]

In evolutionary computation, balancing the diversity and convergence of the population for multiobjective evolutionary algorithms (MOEAs) is one of the most challenging topics. Decomposition-based MOEAs are efficient for population diversity, especially when the branch partitions the objective space of multiobjective optimization problem (MOP) into a series of subspaces, and each subspace retains a set of solutions. However, a persisting challenge is how to strengthen the population convergence while maintaining diversity for decomposition-based MOEAs. To address this issue, we first define a novel metric to measure the contributions of subspaces to the population convergence. Then, we develop an adaptive strategy that allocates computational resources to each subspace according to their contributions to the population. Based on the above two strategies, we design an objective space partition-based adaptive MOEA, called OPE-MOEA, to improve population convergence, while maintaining population diversity. Finally, 41 widely used MOP benchmarks are used to compare the performance of the proposed OPE-MOEA with other five representative algorithms. For the 41 MOP benchmarks, the OPE-MOEA significantly outperforms the five algorithms on 28 MOP benchmarks in terms of the metric hypervolume. [ABSTRACT FROM AUTHOR]

The unclear contraction behavior of Mg-Gd-Y-Zr alloy during low-pressure sand casting bring obstructs into the dimensional control in the fabrication of large and complex parts, restricting the further engineering applications of this alloy. This paper investigated the rule for free and constrained contraction of typical Mg-Gd-Y-Zr (Mg-9Gd-3Y-0.5Zr, VW93K) alloy during low-pressure sand casting. A series of castings with different volumes and geometric structures were designed and a 3D scanner was employed to measure different types of dimensions, which were then used for the calculation of contraction coefficients. The convergent value of free contraction coefficients was derived through statistical analysis, and the correlation between constrained contraction coefficients and geometric characteristics of castings was established by the utilizing of core volume factor. In the condition of low-pressure casting, free contraction coefficients of VW93 alloy are concentrated around a fixed value of 1.72%, constrained contraction coefficients of VW93 alloy show a decreasing linear tendency against core volume factor, and pouring pressure makes effects on free contraction. The experimental results and proposed formulas provide guidance for accurate dimensional control in fabrication of large and complex Mg-RE alloy parts by low-pressure sand casting. [ABSTRACT FROM AUTHOR]

Cast Al-Li alloys show attractive potential for application in the field of manufacturing large-size and complex parts as a result of profound weight reduction and good fluidity. However, the ductility and strength of sand-cast Al-Li alloys are relatively poor due to the low cooling rate of sand casting. In this study, Sc and Ti were added to sand-cast Al-Li-Cu-Mg-Zr casting alloy to investigate the microstructure evolution and tailor the final performance for the first time. The results showed that grain decreased from 189 µm to 56 µm and the needle Cu-rich phase increased in the vicinity of grain boundaries as the total element content of Sc and Ti increased. After aging at 175 °C, the enrichment of the T 1 and S′ phases, the finer δ′, the higher number density of core-shell composites, and the narrowed δ′-precipitation free zones (δ′-PFZs) were stimulated by Sc and Ti, leading to a significant increase in strength of the peak-aged alloy. The SZT alloy exhibits the best yield strength of 359 MPa and ultimate tensile strength of 452 MPa with an adequate elongation of 4.6 %. In addition, a Li-rich zone was observed and intersected with T 1 phase, which provided a new precipitation path for Li atom diffusion and nucleation of T 1 precipitates. The present study suggests that microalloying with Sc and Ti is expected to be an effective strategy to simultaneously improve the strength and ductility of sand-cast Al-Li alloys. • The effect of Sc and Ti on the microstructure evolution of strengthening phases is analyzed. • A good combination of strength and elongation is obtained by the combined addition of Sc and Ti. • The contributions from different strengthening mechanisms for peak-aged Al-Li-Cu-Mg-Zr alloy were studied in detail. [ABSTRACT FROM AUTHOR]

Purpose: In this study, we investigated the effects of different concentration of propofol on cell viability of hippocampal neurons and explored the possible mechanism. Patients and methods: Primary hippocampal neurons were cultured in vitro and treated with different concentration of propofol. MTT was used to examine the survival of neurons. Flow cytometry was used to detect the neuronal apoptosis. Western-blot analysis was used to examine the expression level of p-p38MAPK and p38MAPK. Results: We found that low concentration propofol (0.5 μM and 1 μM) promoted the cell survival rate; however, high concentration of propofol (10 μM,50 μM,100 μM,150 μM, and 200 μM) decreased the cell survival rate (P < 0.05). Flow cytometry showed that the neuronal apoptosis rate was decreased in 1 μM propofol group (P < 0.05), but was significantly higher in10μM, 100 μM and 200 μM groups in a concentration-dependent manner (P < 0.05 or P < 0.01). Western blot revealed that the propofol induced the phosphorylation of p38MAPK concentration-dependently and time-dependently. SB203580, one inhibitor of p38MAPK, increased the cell survival rate and decreased the cell apoptosis induced by high concentration of propofol. Conclusion: Low concentration of propofol improved the survival rate of neurons, while high concentration of propofol promoted the cell apoptosis and decreased the cell viability. p38MAPK pathway is involved the effect of high concentration of propofol promoted on primary hippocampal neurons viability and apoptosis. [ABSTRACT FROM AUTHOR]

A strategy for efficaciously regulating perovskite crystallinity is proposed by using a volatile solid glycolic acid (HOCH2COOH, GA) in an FA0.85MA0.15PbI3 (FA: HC(NH2)2; MA: CH3NH3) perovskite precursor solution that is different from the common additive approach. Accompanied with the first dimethyl sulfoxide sublimation process, the subsequent sublimation of GA before 150 °C in the FA0.85MA0.15PbI3 perovskite film can artfully regulate the perovskite crystallinity without any residual after annealing. The improved film formation upon GA modification induced by the strong interaction between GA and Pb2+ delivers a champion power conversion efficiency (PCE) as high as 21.32%. In order to investigate the role of volatility in perovskite solar cells (PSCs), nonvolatile thioglycolic acid (HSCH2COOH, TGA) with a similar structure to GA is utilized as an additive reference. Large perovskite grains are obtained by TGA modification but with obvious pinholes, which directly leads to an increased defect density accompanied by a decline in PCE. Encouragingly, the champion PCE achieved for GA‐based PSC device (21.32%) is almost 13% or 20% higher than those of the control device or TGA‐based device. In addition, GA‐modified PSCs exhibit the best stability in light‐, thermal‐, and humidity‐based tests due to the improved film formation. [ABSTRACT FROM AUTHOR]

Manganese–zinc (MnZn) power ferrites own significant applications in inductors and transformers for power conversion. The performance of these components is dependent on permeability, saturation induction, core losses, and dc bias superposition characteristics of MnZn ferrites. It is worth emphasizing that excellent dc bias superposition characteristics of ferrites are beneficial for the stability and efficiency of power converters operated with both ac and dc signals. In this paper, Co2O3-doped MnZn ferrites are fabricated using a solid-state reaction method and used to investigate dc bias superposition characteristics of permeability and core losses. More importantly, the physical mechanism of the dc bias superposition characteristics is clarified. Furthermore, the effect of Co2O3 doping on the efficiency of buck circuit was also investigated. The dc bias superposition characteristics suggests potential application in power components and systems. [ABSTRACT FROM AUTHOR]

The certified power conversion efficiency (PCE) record of colloidal quantum dot solar cells (QDSCs) has considerably improved from below 4% to 16.6% in the last few years. However, the record PCE value of QDSCs is still substantially lower than the theoretical efficiency. So far, there have been several reviews on recent and significant achievements in QDSCs, but reviews on photoexcited carrier dynamics in QDSCs are scarce. The photovoltaic performances of QDSCs are still limited by the photovoltage, photocurrent and fill factor that are mainly determined by the photoexcited carrier dynamics, including carrier (or exciton) generation, carrier extraction or transfer, and the carrier recombination process, in the devices. In this review, the photoexcited carrier dynamics in the whole QDSCs, originating from individual quantum dots (QDs) to the entire device as well as the characterization methods used for analyzing the photoexcited carrier dynamics are summarized and discussed. The recent research including photoexcited multiple exciton generation (MEG), hot electron extraction, and carrier transfer between adjacent QDs, as well as carrier injection and recombination at each interface of QDSCs are discussed in detail herein. The influence of photoexcited carrier dynamics on the physiochemical properties of QDs and photovoltaic performances of QDSC devices is also discussed. [ABSTRACT FROM AUTHOR]

Highlights: Butylamine-modified graphene oxide (BTA@GO) is first utilized in PbS colloidal quantum dots (CQDs) ink to deposit the active layer of colloidal quantum dot solar cells (CQDSCs). The BTA@GO improves the carrier transfer rate in the CQDs active layer and 11.7% conversion efficiency is achieved.Solution-processed colloidal quantum dot solar cells (CQDSCs) is a promising candidate for new generation solar cells. To obtain stable and high performance lead sulfide (PbS)-based CQDSCs, high carrier mobility and low non-radiative recombination center density in the PbS CQDs active layer are required. In order to effectively improve the carrier mobility in PbS CQDs layer of CQDSCs, butylamine (BTA)-modified graphene oxide (BTA@GO) is first utilized in PbS-PbX2 (X = I−, Br−) CQDs ink to deposit the active layer of CQDSCs through one-step spin-coating method. Such surface treatment of GO dramatically upholds the intrinsic superior hole transfer peculiarity of GO and attenuates the hydrophilicity of GO in order to allow for its good dispersibility in ink solvent. The introduction of BTA@GO in CQDs layer can build up a bulk nano-heterojunction architecture, which provides a smooth charge carrier transport channel in turn improves the carrier mobility and conductivity, extends the carriers lifetime and reduces the trap density of PbS-PbX2 CQDs film. Finally, the BTA@GO/PbS-PbX2 hybrid CQDs film-based relatively large-area (0.35 cm2) CQDSCs shows a champion power conversion efficiency of 11.7% which is increased by 23.1% compared with the control device. [ABSTRACT FROM AUTHOR]

Delayed asymmetric Coulomb fission in size-selected molecular dication clusters has been recorded for the first time. Observations on (NH3)n2+ clusters show that fragmentation accompanied by charge separation can occur on a microsecond time scale, exhibits considerable asymmetry, and involves a kinetic energy release of ∼0.9 eV. The fission process has been modeled by representing the fragments as charged dielectric spheres and the calculated maximum in the electrostatic interaction energy between the fragments gives a good account of the measured kinetic energy release. A simple kinetic model shows that instrumental factors may contribute to the observation of asymmetric fragmentation. [ABSTRACT FROM AUTHOR]

• Precipitation microstructures and mechanical properties of Al-2Li-2Cu-0.5 Mg-0.15Sc-0.1Zr-0.1Ti alloy aged at 175 °C are investigated. • The precipitates of alloy aged at 175 °C mainly consisted of T 1 , δ′, core–shell phase, S′ and cubic phase. • The cubic phase was transformed from Al 6 Cu 5 Li 2 to Al 6 Cu 5 Mg 2 with the aging time increasing from 8 h to 64 h. The microstructure evolution corresponding to the mechanical properties of cast Al-2Li-2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloy aged at 175 °C was investigated, especially in the identification and variation of the cubic phase. The yield strength and ultimate strength of the peak-aged alloy reach 449 MPa and 502 MPa, respectively. From the transmission electron microscopy characterization, it was found that the precipitates primarily consisted of the cubic phase, T 1 (Al 2 CuLi), S′(Al 2 CuMg), core–shell particles and δ′(Al 3 Li) phases. Longer exposure to temperature changed the composition from Al 6 Cu 5 Li 2 to Al 6 Cu 5 Mg 2 , and these two phases are in competition with the T 1 and S′ phases. [ABSTRACT FROM AUTHOR]

Retraction of 'Synthesis of atomic form nickel co-catalysts on TiO2 for improved photocatalysis via the RAFT technique' by Bo Zhang et al., New J. Chem., 2022, 46, 14239–14250, https://doi.org/10.1039/D2NJ02069F. [ABSTRACT FROM AUTHOR]

The main difficulties of using the deep learning model to decouple the orbital angular momentum (OAM) in Free-Space Optical (FSO) communication are that the model requires a large number of training data sets and the model's convergence speed is low. In this paper, transfer learning and depthwise separable convolution are combined to improve the computational speed of the model and to reduce the requirement of training data set size. The recognition accuracies of 4-OAM and 8-OAM based on the measured data with noise are studied respectively and the OAM transmission in atmospheric turbulence are simulated to test the robustness of the model. In addition, the proposed method can be trained on the expanded data set of 38 experimental data collection, and the test classification results can reach 99.5%. Meanwhile, the minimum accuracy of the model in testing data of different transmission distances and turbulence intensities is 81.25%, indicating good robustness. The paper's work on the OAM pattern detection has great significance. • The method can reduce the limitation deep learning model depend on data to promote the development of OAM detection. • The model can improve the computational speed of the model and reduce the requirement of training data set size. • The method was trained on the expanded data set of 38 experimental samples, and classification rate reached 99.5%. • The method had good robustness in testing data of different transmission distance and turbulence intensity. • The method reduce the influence of data change on model accuracy and improve the flexibility of OAM identification. [ABSTRACT FROM AUTHOR]

Abstract This work was undertaken to investigate the influence of independent and combined additions of Mg and Sc on the microstructure, mechanical properties, and thermal stability of cast Al-2Li-2Cu-0.2Zr base alloy after thermal exposure. All studied alloys were exposed at 100 °C for 1000 h after a prior artificial ageing of 24 h at 150 °C to simulate the thermal exposure under service conditions. A significant increase in strength took place in all alloys, accompanied by different variations of toughness as a result of exposure. It is proposed that the toughness reduction in base Al-2Li-2Cu-0.2Zr alloy should be primarily attributed to the precipitation of θ′′/θ′ (Al 3 Cu/Al 2 Cu) plates together with complementary nucleation and coarsening of δ′ (Al 3 Li) particles. Addition of Mg has a pronounced effect on the competitive precipitation behavior, which will suppress the precipitation of θ′′/θ′ plates and encourage formation of S′ (Al 2 CuMg) phase. Significant grain refinement and increased Al 3 (Li, Sc, Zr) precipitation was obtained with minor Sc addition, contributing to the significant enhancement of ductility. Sc addition is revealed to promote the precipitation of refined θ′′/θ′ plates, primarily contributing to the significant strength enhancements. The additions of Mg and/or Sc could efficiently improve the strength and thereby reduce the susceptibility to exposure embrittlement of the base alloy during exposure. An excellent combination of strength (YS = 377 MPa, UTS = 478 MPa) and ductility (EL = 8.4%) after exposure could be obtained in the alloy with combined Mg and Sc addition. Graphical abstract Image 1 Highlights • Microstructural stability of cast Al-Li-Cu alloys was investigated. • Mg addition greatly retards the precipitation of θ′′/θ′ during exposure. • Sc addition synchronously improves the alloy strength and toughness. • The highest UTS of 497 MPa is obtained. [ABSTRACT FROM AUTHOR]

The effects of Ce-rich RE on the microstructure and mechanical properties of as-cast Mg-8Li-3Al-2Zn-0.5Nd- x RE (x = 0, 1, 2, 3 wt%) alloys were investigated. The results indicated that the as-cast Mg-8Li-3Al-2Zn-0.5Nd alloy mainly consisted of α -Mg, β -Li, AlLi, MgLi 2 Al and Al 2 Nd phases. With the addition of Ce-rich RE in the alloy, Al 3 RE and Al 2 RE phases generated and gradually grew into net-like or block-like structure. With the addition of RE, Al-RE phases generated by consuming Al element and, thus, less Al element was dissolved in the matrix and less AlLi phase formed. Furthermore, less AlLi phase means that more Li element released to cause the increase of β -Li phase and refine the α -Mg phase. Under the influence of these factors, adding more RE led to higher elongation and lower tensile strength and hardness. With the addition of Ce-rich RE, the yield strength and ultimate tensile strength of the as-cast Mg-8Li-3Al-2Zn-0.5Nd alloy gradually decreased from 180 to 152 MPa and from 215 to 193 MPa, respectively, while the elongation was remarkably improved from 21.1% to 40.2%. Image 1 • Mg-9Li-3Al-2Zn-0.5Nd- x RE (x = 0, 1, 2, 3 wt%) alloys were smelted in the atmosphere rather than in a vacuum environment. • Ce-rich RE addition leads to the increase of Al 2 RE, Al 3 RE and β-Li phases and the decrease of AlLi phase. • The α-Mg phase of the alloy refined and spheroidized. • The elongation of the alloy was greatly increased by adding Ce-rich RE. [ABSTRACT FROM AUTHOR]

Highlights • Pilot FDD Framework with Bayesian network as core for NPP of PWR is studied. • Multi-source information is tackled by PCA, data fusion and fuzzy theory. • Data accuracy is improved based on PCA and data fusion in multi-source information. Abstract Fault detection and diagnosis (FDD) provides safety alarms and diagnostic functions for a nuclear power plant (NPP), which comprises large and complex systems. Here, a technical framework based on a Bayesian network (BN) for FDD is introduced because of its advantages of easy visualization, expression of parameter uncertainties, and ability to perform diagnosis with incomplete data. However, a BN raises a new problem when it is applied to NPPs; i.e., how to cope with parameter or node information from multiple sensors. Sensor data must be consolidated because creating a single node for each sensor in the network would lead to information overload. This paper proposes a possible solution to this issue and then constructs an FDD system framework with a BN as the backbone. Within this framework, principal component analysis is used to remove information from malfunctioning sensors, and fuzzy theory and data fusion are combined to further improve data accuracy and combine data from multiple sensors into one node. On this basis, a BN inference junction tree algorithm is used in FDD because it can deal with incomplete data. A BN model for a pressurized water reactor is created to validate the method framework. Simulation experiments indicate the suitability of the proposed method for online FDD in NPPs using multi-sensor information. It is thus concluded that the proposed method is a feasible scheme for the FDD of NPPs. [ABSTRACT FROM AUTHOR]

Manganese-zinc (MnZn) ferrites have important application in convertors and switching mode power supplies. The core losses ($\text{P}_{L}$) of MnZn ferrites have serious influence on the performance of power conversion devices. It is worth emphasizing that reducing the core losses at high frequency is of great significance for the miniaturization and integration of power conversion devices. Here in this paper, MnZn ferrites have been fabricated by the method of solid-state reaction, and the effect of CaCO3 and V2O5 co-additives on the microstructure and magnetic property has been investigated. This paper illustrated the competition mechanism of grain growth, which originated from the hindrance effect of CaCO3 and acceleration effect of V2O5, as well as the effect of CaCO3 and V2O5 on core losses by means of loss separation method. In addition, as for the MnZn ferrite sample with 0.1 wt% CaCO3 and 0.01 wt% V2O5 co-additives, core losses were suppressed to 46 and 664 kW/m3 corresponding to 3 MHz 10 mT and 3 MHz 30 mT at 25 °C, respectively. The state-of-the-art MnZn ferrites with ultralow core losses own potential application for high-frequency power conversion devices. [ABSTRACT FROM AUTHOR]

Based on the extended Huygens–Fresnel principle, an analytical expression for the cross-spectral density of optical coherence lattices (OCL) in oceanic turbulence is derived. With the help of this expression, we investigate the propagation of OCL in oceanic turbulence. In order to increase underwater optical communication distance, we investigated the effects of source parameters, such as lattices constant, wavelength and beam width, on intensity distribution of OCL in oceanic turbulence. Results indicate that the light intensity received by receiver increases with the increase of lattice constant, the increase of beam width and the decrease of wavelength, which may have some potential applications in underwater optical communication. [ABSTRACT FROM AUTHOR]

As a kind of cast aluminum alloy with high strength, Al–Li–Cu–Mg series alloys exhibit desirable stiffness and formability, while a limited investigation has discussed the influence of cooling rate on microstructure and mechanical properties of these alloys. In this work, the effect of cooling rate during casting on microstructure evolution and mechanical properties of cast Al–2Li–2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloy was investigated using a step-like iron mold. The results showed that the increased cooling rate refined the grain size and augmented the volume fraction of second phase in the as-cast microstructure. In the aging process, the rapid cooling rate markedly promotes precipitation and suppresses coarsening of the δˊ(Al 3 Li), T 1 (Al 2 CuLi) and Sˊ(Al 2 CuMg) phases, which plays a vital role in enhancing strength of the peak-aged alloy. In addition to diffusion and vacancy mechanisms, a Li-rich zone offers a new precipitation pathway for T 1 precipitates. Notably, the rapid cooling rate of 16.1 °C/s significantly facilitated the formation and inhomogeneous distribution of the cubic σ(Al 6 Cu 5 Mg 2) phase, which competed with the T 1 and Sˊ phases for Cu and Mg atoms. Finally, the formation mechanism of the σ phase under different cooling rates was discussed, and the strengthening and fracture mechanisms were quantified. The present work is expected to enlighten the understanding of the microstructure evolution of Al–Li alloys with varied cast cooling rates. [ABSTRACT FROM AUTHOR]

Small modular reactors (SMRs) are rapidly developed worldwide in recent years for their potential extensive applications. China is very active in promoting SMR design and construction. However, the current emergency preparedness (EP) guidance in China is developed based on the characteristics of large water-cooled reactors, and they are only partially applicable to SMRs. In our previous work, we have fully demonstrated from a technical perspective that it is feasible for China to establish a unified EP framework for all SMR designs based on the dose and consequence of an accident spectrum. Therefore, this paper will comprehensively discuss the costs and benefits of establishing a unified EP guidance for all SMR designs in China. Uncertainty analysis is also conducted for variables with great uncertainty. Through the study in this paper, it can be concluded that developing a new unified EP regulatory guidance for all SMR designs in China is cost beneficial in most cases. In addition, it will also bring other benefits that are hard to be quantified, such as the consistency of supervision, the clarity of the EP plan, and the improved engagement of all stakeholders during SMR development. In a word, it would always be beneficial to establish a new unified EP regulatory guidance for all SMR designs in the long term. • The fact that current emrgency preparedness guidance is only partially applicable for licensing SMR. • This paper proposes an operable process of cost-benefit analysis for regulatory guidance formulation. • Quantification approach is used to discussed cost-benifit analysis in guidance development. [ABSTRACT FROM AUTHOR]

In third-generation Al–Cu–Li alloys, T 1 , S', and θ' precipitates are the primary strengthening phases, and the strength-ductility synergy of the alloys depends strongly on their precipitation behavior. This study aimed to regulate the precipitation behavior among these precipitates by optimizing Ag/Mg ratio in Al–Cu–Li alloys, and its influence on mechanical properties and fracture mechanism was investigated. To this end, four alloys were designed with a total content of 1.1 wt% of Ag and Mg, and an Ag/Mg ratio ranging from 0.24 to 5.63. The results shows that an increase in the Ag/Mg ratio dramatically accelerated the ageing process and shortened the peak-ageing time. At 150 °C, the precipitation sequence of alloys with an Ag/Mg ratio below 0.95 was SSS→GPB zone +δ′/β'→S'+T 1 , which transformed into SSS→GP zone +δ′/β'→θ'+T 1 when the Ag/Mg ratio was above 1.87. The T 1 , S', and θ' precipitates coexisted and were dispersedly distributed among studied alloys with an Ag/Mg ratio ranging from 0.95 to 1.87. An Ag/Mg ratio of 1.87 resulted in the fastest ageing hardening response and the highest strength (YS = 705 MPa, UTS = 717 MPa) because of the highest volume fraction of T 1 precipitates. Moreover, the fracture mode changed from transgranular fracture to intergranular fracture with increasing Ag/Mg ratio due to the difference in distribution and number density of these precipitates between the matrix and grain boundary. [ABSTRACT FROM AUTHOR]

Cervical cancer is one of the most common malignant tumors among female gynecological diseases. This paper aims to explore the feasibility of utilizing serum Fourier Transform Infrared (FTIR) spectroscopy, combined with machine learning and deep learning algorithms, to efficiently differentiate between healthy individuals, hysteromyoma patients, and cervical cancer patients. In this study, serum samples from 30 groups of hysteromyoma, 36 groups of cervical cancer, and 30 healthy groups were collected and FTIR spectra of each group were recorded. In addition, the raw datasets were averaged according to the number of scans to obtain an average dataset, and the raw datasets were spectrally enhanced to obtain an augmentation dataset, resulting in a total of three sets of data with sizes of 258, 96, and 1806, respectively. Then, the hyperparameters in the four kernel functions of the Support Vector Machine (SVM) model were optimized by grid search and leave-one-out (LOO) cross-validation. The resulting SVM models achieved recognition accuracies ranging from 85.0% to 100.0% on the test set. Furthermore, a one-dimensional convolutional neural network (1D-CNN) demonstrated a recognition accuracy of 75.0% to 90.0% on the test set. It can be concluded that the use of serum FTIR spectroscopy combined with the SVM algorithm for the diagnosis of cervical cancer has important medical significance. [ABSTRACT FROM AUTHOR]

In [Countable thin Π10 classes, Ann. Pure Appl. Logic59 (1993) 79–139], Cenzer, Downey, Jockusch and Shore proved the density of degrees (not necessarily c.e.) containing members of countable thin Π10 classes. In the same paper, Cenzer et al. also proved the existence of degrees containing no members of thin Π10 classes. We will prove in this paper that the c.e. degrees containing no members of thin Π10 classes are dense in the c.e. degrees. We will also prove that the c.e. degrees containing members of thin Π10 classes are dense in the c.e. degrees, improving the result of Cenzer et al. mentioned above. Thus, we obtain a new natural subclass of c.e. degrees which are both dense and co-dense in the c.e. degrees, while the other such class is the class of branching c.e. degrees (See [P. Fejer, The density of the nonbranching degrees, Ann. Pure Appl. Logic24 (1983) 113–130] for nonbranching degrees and [T. A. Slaman, The density of infima in the recursively enumerable degrees, Ann. Pure Appl. Logic52 (1991) 155–179] for branching degrees). [ABSTRACT FROM AUTHOR]

In this paper, we prove Kierstead's conjecture for linear orders whose order types are ∑ q ∈ Q F ( q ) , where F is an extended 0′-limitwise monotonic function, i.e. F can take value ζ . Linear orders in our consideration can have finite and infinite blocks simultaneously, and in this sense our result subsumes a recent result of C. Harris, K. Lee and S.B. Cooper, where only those linear orders with finite blocks are considered. Our result also covers one case of R. Downey and M. Moses' work, i.e. ζ ⋅ η . It covers some instances not being considered in both previous works mentioned above, such as m ⋅ η + ζ ⋅ η + n ⋅ η , for example, where m , n > 0 . [ABSTRACT FROM AUTHOR]

This paper reports the impacts of direct feeding silkworms with different nanoparticles (Cu, Fe, and TiO 2 ) on the morphology, structures, and mechanical properties of the resulting silk fiber (SF). The contents of the Cu nanoparticles were 38 times higher in the posterior silk glands and only 2–3 times higher in the SF and in the middle silk glands compared with the controlled groups. Significant changes of the surface morphology, structures, and diameter of the Cu nanoparticle fed SF have been observed, which are attributed to a slight SF protein reconstruction or conformational change in the mixture of silk fibroin and sericin in the silk glands. The resulting Cu-containing SF exhibits good tensile strength of 360 MPa and reaches a strain of 38%, which are 89% and 36% higher than those of the natural SF. This study offers a new green strategy for the easy modification to achieve robust composite SF. [ABSTRACT FROM AUTHOR]

The utilization of Co-Cr-Fe-based black pigments bears considerable significance within the realm of commercial ceramic pigments, owing to their distinctive spinel structure, remarkable high-temperature stability, and exceptional chromatic attributes. This study delves into the synthesis of diverse black pigment configurations by employing the co-precipitation method, leveraging the interplay of these three metallic oxides. This investigation encompasses a comprehensive scrutiny of ion valences, crystal structures and parameters, colorimetric properties, and their interrelationships. The methodology integrates the response surface methodology (RSM) framework, using theoretical formulations to navigate the material ratios and elucidating the associations between the resultant compositions and color coordinate values, aligned with the CIE-Lab* colorimetric methodology. The derived predictive models yielded an optimized black pigment composition, characterized by heightened black intensity and a refined formulation. [ABSTRACT FROM AUTHOR]

Cobalt blue ceramic pigments mainly consisting of CoAl2O4 are subject to the difficulty of color control. Here, a perspective is reported regarding research on the reasons for color change based on the control of the heat treatment and ratio of components. Macroscopically, the composition of pigment powders determines the color. Microscopically, the crystallite characters including size, cation distribution, and structure have an important effect on the color. The ingredient, structural, and color properties of the pigment powders are analyzed using thermo gravimetry–differential scanning calorimetry (TG–DSC), X-ray diffraction (XRD) measurement, Rietveld refinement, energy dispersive spectrometer (EDS), and colorimetry analysis. The color is proven to be associated with cation distribution, such as that of Co2+ and Co3+. It is indicated that high heating temperature, long heating time, and a large proportion of Al3+ can, respectively, induce the Co2+ and Al3+ in tetrahedral and octahedral sites. [ABSTRACT FROM AUTHOR]

Four new bistridentate Ru(II) complexes having a combination of ligands, 4,4′-dicarboxy-2,2′:6,2″-terpyridine or its 2-hexylthiophene-substituted derivative as the anchoring ligand on one hand and one of tetrazolylpyridine-based ligands having a NˆNˆN coordination pattern or C − ˆNˆN coordination pattern as the auxiliary ligand on the other are reported as sensitizers for dye-sensitized solar cells (DSSCs), along with their spectroscopic, electrochemical, and theoretical characterizations. For the anchoring ligand, the introduction of 2-hexylthiophene unit leads to narrower spectral response and lower molar extinction coefficients and a smaller driving force for dye regeneration. For the ancillary ligand, the cyclometalating Ru C bond induces a red shift in absorption compared with a Ru N bond and thus affords a photocurrent generation at wavelengths of up to 950 nm. Further, the overall efficiencies of DSSCs are higher with the NˆNˆN complexes than with the C − ˆNˆN complexes, mainly due to higher open-circuit voltages ( V oc ). Overall, the DSSC based on the bistetrazolate dye without the hexylthiophene unit for the anchoring ligand and having the NˆNˆN coordination pattern for the auxiliary ligand exhibited the highest efficiency of 5.9% when employing 0.5 M t -butylpyridine in the electrolyte. [ABSTRACT FROM AUTHOR]

A cyclometalated ruthenium complex with 6-( ortho -methoxyphenyl)-2,2'-bipyridine (MeO-L) and tricarboxyterpyridine (tpy(CO 2 H) 3 ) ( RuCC·PF 6 ) was prepared, characterized, and evaluated as a dye for dye-sensitized solar cells (DSSCs). The first oxidation and reduction potentials are +0.99 V and −0.81 V vs NHE, respectively. This complex exhibits panchromatic absorption spectrum extending up to 800 nm. The transitions upon visible light excitation were mixtures of metal-to-ligand (Ru → tpy(CO 2 H) 3 ) and interligand (MeO-L → tpy(CO 2 H) 3 ) charge transfer transitions. Adsorption of the ruthenium complex on TiO 2 was carried out from solutions of RuCC·PF 6 in the free acid form or solutions of RuCC·(NBu 4 ) 2 in a deprotonated carboxylate form. The DSSC devices employing these complexes as the dye sensitizers generate electricity in response to light over the whole visible range and into the near infrared region over 900 nm. Remarkably, RuCC·(NBu 4 ) 2 recorded higher short-circuit current density than a benchmark N719, while the open-circuit voltage was lower, resulting in a modest overall photon-to-current conversion efficiency of 6.4%. The transient absorption and electrochemical impedance spectroscopy have been conducted to get insight into the mechanistic details of the DSSC cells, which suggested that the presence of NBu 4 cation was beneficial in retarding the unwanted recombination reaction. Considering the efficient charge injection and regeneration as manifested by the large short-circuit current, modification based on the present structure would be a promising strategy toward higher efficiency dyes for DSSCs. [ABSTRACT FROM AUTHOR]

The effects of solution heat treatment and aging on the microstructural evolution and mechanical behavior of a squeeze-cast (SC) Mg-10Gd-3Y-0.5Zr (GW103K) alloy, processed using various applied pressures (e.g., 0.1, 40, 80 and 160 MPa) were systematically investigated. Our results show that, after solution heat treatment, secondary phases and pressure-induced dislocations are dissolved in the matrix of the squeeze-cast alloys. Moreover, subsequent aging heat treatment leads to an increased age-hardening response relative to that in squeeze-cast GW103K and this trend increases with increasing applied pressure. The room temperature tensile test results show that the yield strength (YS) for the squeeze-cast alloy in the as-cast, the as-T4 heat-treated and the as-T6 heat-treated states increases with increasing applied pressure, from 0.1 to 80 MPa, and remains relatively constant when the applied pressure is increased to 160 MPa, whereas the ultimate tensile strength (UTS) and elongation-to-failure ( E ) increases continuously with increasing applied pressure. The measured increases in YS and UTS (or E ), are discussed in terms of the mechanisms that govern the evolution of microstructure in squeeze-cast GW103K, paying particular attention to gain size and porosity. [ABSTRACT FROM AUTHOR]

The microstructures and mechanical properties of cast Al-3Li- x Cu-0.2Zr alloy were investigated. The results showed that Cu addition could slightly refine the grain size of as-cast alloy. Cu element was significantly enriched at the grain boundaries, and Cu-rich intermetallic compounds were formed in the Cu-containing alloys during casting. The peak hardness increased and the time to peak ageing decreased with the increase of Cu content. Cu addition also had a pronounced influence on the precipitation behavior of Al-3Li- x Cu-0.2Zr alloys, i.e. the number density, size and distribution of T 1 -Al 2 CuLi and θ ′-Al 2 Cu phases. The tensile strength was effectively improved after 2 wt% Cu addition compared with Al-3Li-0.2Zr alloy. A good combination of strength to ductility could be obtained in Al-3Li-2Cu-0.2Zr alloy after solution and ageing 32 h at 175 °C. The precipitation-free zones (PFZs) were developed with the coarsening of δ′-Al 3 Li particles in the peak-aged (PA) and over-aged (OA) state, promoting the poor ductility and premature failure. [ABSTRACT FROM AUTHOR]

A new series of thiocyanate-free bis-tridentate Ru(II) complexes containing azole ligands as well as an organometallic Ru–C bond are synthesized, characterized, and evaluated in dye-sensitized solar cells (DSSCs). CF 3 -substituted pyrazolyl, CF 3 -substituted triazolyl, and tetrazolyl derivatives are employed as ligands in the three neutral complexes PYZ, TRZ, and TEZ dyes, respectively. Despite their different structures, all the three complexes exhibit similar absorption features and panchromatic absorption covering the visible and near-IR regions. By switching from a pyrazolyl via triazolyl to tetrazolyl moiety in the ligand, the photocurrent value, open-circuit voltage, and overall efficiency are increased accordingly under the same conditions. Among them, photon-to-current conversion efficiency ( ƞ ) of TEZ dye reaches the maximum of 6.44% with a short-circuit photocurrent density ( J sc ) of 17.8 mA cm −2 , an open-circuit photovoltage ( V oc ) of 0.54 V and fill factor (FF) of 0.67 under illumination of an AM1.5G solar simulator. TEZ dye shows a good long term light soaking stability and maintains up to more than 90% of the initial power conversion efficiency after 1000 h. [ABSTRACT FROM AUTHOR]

In this study, a high-performance Mg-3Nd-3Gd-0.2Zn-0.5Zr alloy is prepared. The precipitate microstructures of the studied alloy during isothermal aging at 225 °C are characterized by HAADF-STEM observations, and the corresponding mechanical properties are also investigated. It is noted that the evolution of the precipitate microstructure is mainly divided into three stages: the precipitation and growth of β″, the transition from β″ to β 1 , and the ripening of β 1. There are apparent differences in the mechanical properties of alloy in these three stages. At the beginning of aging treatment, due to the precipitation and growth of β″, the yield strength of alloy increases rapidly while the elongation decreases. Afterwards, the transition of precipitates from β″ to β 1 leads to the simultaneous increment in the yield strength and elongation of the alloy. Finally, as the β 1 precipitates ripen, the yield strength of the alloy decreases while its elongation shows a trend of increment owing to the significantly improved dimensions and reduced number density. • Precipitate microstructures and mechanical properties of Mg-3Nd-3Gd-0.2Zn-0.5Zr alloy aged at 225 °C are investigated. • A good combination of strength and elongation is achieved at over-aged Mg-3Nd-3Gd-0.2Zn-0.5Zr alloy • Transition from β″ to β 1 leads to simultaneous increments in the yield strength and elongation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mg-Y-rE-Zr alloy without obvious defects is fabricated by WAAM. • Microstructural homogeneity occurs along the deposited direction. • The precipitates of Mg 3 (Nd, Y) and Mg 14 Nd 2 Y are found in the1st layer. • The bottom part of the deposited wall exhibits a higher hardness. This work fabricates Mg-4Y-3RE-0.5Zr alloy by wire arc additive manufacturing (WAAM). The oxidation inclusion, as one of the main defects in the Y-containing Mg alloys prepared by laser powder bed fusion (LPBF), has not been observed. However, microstructural inhomogeneity along the building height appears due to the combined effect of the different cooling rates of different deposited layers and the subsequent multiple thermal cycles (MTCs). The effect of the microstructural inhomogeneity on the hardness distribution of the deposited wall was also revealed. It is believed that this study provides some new findings to the additive manufacturing of high-performance magnesium rare-earth (Mg-RE) alloys. [ABSTRACT FROM AUTHOR]