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Cancer nanomedicine has been an emerging field for drug development against malignant tumors during the past three decades. A bibliometric analysis was performed to characterize the current international trends and present visual representations of the evolution and emerging trends in the research and development of nanocarriers for cancer treatment. This study employed bibliometric analysis and visualization techniques to analyze the literature on antitumor nanocarriers published between 2013 and 2023. A total of 98,980 articles on antitumor nanocarriers were retrieved from the Web of Science Core Collection (WoSCC) database and analyzed using the Citespace software for specific characteristics such as publication year, countries/regions, organizations, keywords, and references. Network visualization was constructed by VOSviewer and Citespace. From 2013 to 2023, the annual global publications increased 7.39 times, from 1851 to 13,683. People's Republic of China (2588 publications) was the most productive country. Chinese Academy of Sciences (298 publications) was the most productive organization. The top 5 high-frequency keywords were "nanoparticles," "drug delivery," "nanomedicine," "cancer," and "nanocarriers." The keywords with the strongest citation bursts recently were "cancer immunotherapy," "microenvironment," "antitumor immunity," etc., which indicated the emerging frontiers of antitumor nanomedicine. The co-occurrence cluster analysis of the keywords formed 6 clusters, and most of the top 10 publications by citation counts focused on cluster #1 (nanocarriers) and cluster #2 (cancer immunotherapy). We further provided insightful discussions into the identified subtopics to help researchers gain more details of current trends and hotspots in this field. The present study processes a macro-level literature analysis of antitumor nanocarriers and provides new perspectives and research directions for future development in cancer nanomedicine. [ABSTRACT FROM AUTHOR]

Osteosarcoma is the most common primary malignant bone tumor with a strong tendency to metastasize, limiting the prognosis of affected patients. Genomic, epigenomic and transcriptomic analyses have demonstrated the exquisite molecular complexity of this tumor, but have not sufficiently defined the underlying mechanisms or identified promising therapeutic targets. To systematically explore RNA-protein interactions relevant to OS, we define the RNA interactomes together with the full proteome and the transcriptome of cells from five malignant bone tumors (four osteosarcomata and one malignant giant cell tumor of the bone) and from normal mesenchymal stem cells and osteoblasts. These analyses uncover both systematic changes of the RNA-binding activities of defined RNA-binding proteins common to all osteosarcomata and individual alterations that are observed in only a subset of tumors. Functional analyses reveal a particular vulnerability of these tumors to translation inhibition and a positive feedback loop involving the RBP IGF2BP3 and the transcription factor Myc which affects cellular translation and OS cell viability. Our results thus provide insight into potentially clinically relevant RNA-binding protein-dependent mechanisms of osteosarcoma. Proteomic, transcriptomic, and genomic analysis has shown osteosarcoma (OS) to be a complex and heterogenous disease but revealed little about its carcinogenesis or potential therapeutic targets. Here, the authors profile the RNA interactome, transcriptome and proteome of cells derived from OS patients, identifying a targetable vulnerability to translation inhibition. [ABSTRACT FROM AUTHOR]

This paper proposes a novel robust super-twisting nonsingular fast terminal sliding mode control method for high precision position tracking of permanent magnet linear synchronous motor (PMLSM). Based on the position tracking error of PMLSM, a nonsingular fast terminal sliding mode variable is constructed to avoid the singularity and achieve the convergence of the position error in a finite time. To improve the convergence speed of the super-twisting algorithm and solve the gain overestimation problem of the existing algorithm, a dual-layer nested adaptive adjustment law based on the super-twisting scheme is proposed, which does not need the information of the unknown uncertainties. While ensuring that the conditions of the existence of the sliding mode hold, the control gain is made as small as possible to obtain a continuous switching control law to suppress the effect of the chattering phenomenon. The Lyapunov stability proves the robustness and convergence of the system. Experimental results confirm the effectiveness and feasibility of the designed position tracking control scheme. [ABSTRACT FROM AUTHOR]

Background: Ischemic stroke is a major cause of disability and death worldwide. A narrow therapeutic window profoundly constrained the utilization of alteplase. Objectives: To investigate therapeutic effects and safety of intravenous recombinant human prourokinase (rhPro-UK) in patients with acute ischemic stroke (AIS) in the 4.5–6 h therapeutic time windows. Methods: We conducted a phase IIa, randomized, and open-label multicenter clinical trial. Between 4.5 and 6 h after the onset of AIS, patients were randomly administrated to receive intravenous rhPro-UK at a 50 mg or 35 mg dose. The primary endpoint was excellent functional outcome defined as modified Rankin scale (mRS) score of 1 or less at 90 days. The secondary outcome was the treatment response, which was based on an at least 4-point improvement from baseline National Institutes of Health stroke scale (NIHSS) score at 24 h after drug administration. Safety endpoints included death, symptomatic intracerebral hemorrhage (sICH), and other serious adverse events. Results: We enrolled 80 patients in the 4.5–6 h therapeutic time windows at 17 medical centers in China from December 2016 to November 2017. A total of 39 patients were treated with 50 mg rhPro-UK, and 39 were treated with 35 mg rhPro-UK. Compared with the baseline, the NIHSS score at 24 h and days 7, 14, 30, and 90 was decreased significantly among patients treated with either rhPro-UK 50 mg or 35 mg. The mean reduction in the NIHSS from baseline to 90 days after the onset was 3.56 and 5.79 in the rhPro-UK 50 mg group and the rhPro-UK 35 mg group, respectively. The rates of functional independence at 90 days of rhPro-UK 50 mg and 35 mg were 61.54% and 69.23%, respectively (P = 0.475), and the proportion of patients with functional response to treatment at 24 h were 28.21% and 33.33% (P = 0.624). No sICH occurred in the two groups, and death occurred in only one patient in the rhPro-UK 50 mg group. There was no significant difference in mortality at 90 days and the rate of other serious adverse events between two groups. Conclusion: In the 4.5–6 h time window, more than 60% of patients at either dose of rhPro-UK (50 mg or 35 mg) achieved functional independence at 90 days without increased mortality and sICH risk. Thus, intravenous rhPro-UK was effective and safe for patients with AIS within 4.5–6 h after stroke onset. While no significant differences were identified between different dosages of rhPro-UK regarding clinical outcomes, it is a logical step to further test the safety and efficacy of the low dose of rhPro-UK in a well-powered phase III study. Trial Registration: http://www.chictr.org.cn. Identifier: ChiCTR1800016519. Date of registration: 6 June 2018. [ABSTRACT FROM AUTHOR]

In order to know the advantages of using environmentally friendly materials in construction, namely, aggregates from tire recycling, this study aims to develop a numerical and mathematical model in order to analyze the thermal behavior of concrete on the basis of rubber aggregates as a function of time. The main goal of this paper is to look at how the heat shock temperature of 800 °C and the conditions of exposure to the ISO 834 standard fire affect the thermal behavior of concrete with different amounts of rubber (0%, 10%, 20%, and 30%) and constant humidity (3%). The results obtained show that for all mixtures, the temperature propagated in the sample decreases at different rates depending on the content of rubber aggregates. This reduction is mainly due to the decrease in the ability of the material to transfer heat and the increase in the thermal capacity that must be given to the material to increase its temperature. Statistics, frequency distributions, contours, and 3D views have all shown that the numerical model developed works. This makes the model an important tool and a good way to describe how concretes behave when heated. [ABSTRACT FROM AUTHOR]

This study explores the effect of H2O on the characteristics of the oxy-fuel combustion process preheated by a circulating fluidized bed. The preheating and combustion characteristics have been studied in O2/CO2/H2O and O2/N2/H2O atmospheres. It was observed that the preheating temperature decreased with adding steam. Meanwhile, the addition of steam enhanced the C-H2O gasification reaction, while weakened the C-CO2 gasification reaction. As a result, the H2 concentration was increased, while the CO concentration was reduced. H2O was conducive towards increasing the surface area and pore formation of the preheated char, though it had an insignificant effect on the particle size. Moreover, H2O enhanced the preheated char activity, which was helpful for ignition and stable combustion. The NOx emission was observed to increase from 68 to 79 mg/MJ and 62 to 81 mg/MJ in O2/CO2 and O2/N2 atmospheres, respectively, after adding steam. [ABSTRACT FROM AUTHOR]

The purpose of this study is to test the feasibility for deep CNN–based artificial intelligence methods for automatic classification of the mass margin and shape, while radiomic feature–based machine learning methods were also implemented in this study as baseline and for comparison study. In this retrospective study, 596 patients with breast mass that underwent mammography from 4 hospitals were enrolled from January 2012 to October 2019. Margin and shape of each mass were annotated according to BI-RADS by 2 experienced radiologists. Deep CNN–based AI was implemented for the classification task based on Resnet50. Balanced sampler and CBAM were also used to improve the performance of the Deep CNNs. As comparison, image texture features were extracted and then dimensionality reduction methods (such as PCA, ICA) and classical classifiers (such as SVM, DT, KNN) were used for classification task. Based on Python programming software, accuracy (ACC) was used to evaluate the performance of the model, and the model with the highest ACC value was selected. Deep CNN based on Resnet50 with balanced sampler and CBAM achieved the best performance for both margin and shape classification, with ACC of 0.838 and 0.874, respectively. For the radiomics-based machine learning, the best performance for margin was achieved as 0.676 by the combination of FA + RF, while the best performance for shape was 0.802 by the combination of PCA + MLP. The feasibility for automatic classification with coarse labeling of the mass shape and margin was testified with the deep CNN–based AI methods, while radiomic feature–based machine learning methods achieved inferior classification results. [ABSTRACT FROM AUTHOR]

Introduction: Posterolateral approach has been advocated for the treatment of ankle fractures involving the posterior malleolus and satisfactory results were demonstrated in several studies. The Bartonicek classification based on 3-dimensional CT scanning was commonly used for treatment recommendation of posterior malleolar fracture (PMF). The aim of this retrospective study was to evaluate the clinical effect of the posterolateral approach for the treatment of PMF and present outcomes of patients with different types of Bartonicek classification. Method: We retrospectively reviewed the clinical outcomes of 72 patients with ankle fractures involving posterior malleolus (PM) from January 2016 to December 2018. Posterior malleolus fractures (PMFs) were all directly reduced and fixed by a posterolateral approach using lag screws and/or buttress plates. AOFAS score and VAS pain score were used as the primary functional outcome measures. The radiographic evaluation included the quality of the reduction and Kellgren–Lawrence (KL) osteoarthritis classification. According to the CT-based Bartonicek classification, all patients were classified into three groups: 42 type II, 18 type III and 12 type IV. Bartonicek type II patients were further divided into subtype IIa 19 cases, subtype IIb 16 cases and subtype IIc 7 cases. The radiological and functional outcomes were analyzed among different types and subtypes of Bartonicek classification. Results: Sixty-eight patients (94.5%) achieved good or excellent reduction of PMF after surgery. The mean AOFAS score was 81.35 ± 6.15 at 6 months and 90.56 ± 4.98 at the final follow-up, respectively. The VAS score was 6.62 ± 1.03 one week after surgery, and 1.20 ± 0.92 at the final follow-up. Radiological evaluation at the final follow-up showed that primary bone union was achieved in all patients and 65 patients (88.9%) got no (KL grade 0) or just doubtable (KL grade 1) post-traumatic osteoarthritis. AOFAS scores decreased significantly with the severity of Bartonicek classification at 6 month (p < 0.001) and final follow-up (p < 0.05), while there was no statistical difference of VAS pain score among different types of Bartonicek classification. Reduction quality and the presence of osteoarthritis was not correlated to Bartonicek classification either. Besides, AOFAS scores at the final follow-up were statistically different among three subtypes of Bartonicek type II fractures (p < 0.05), and Bartonicek subtype IIa fractures had the highest AOFAS scores as 93 ± 4.99. Presence and severity of osteoarthritis was lower in patients with subtype IIa PMF compared to other subtype groups, this finding was statistically significant (p < 0.05). Conclusion: The posterolateral approach could achieve good clinical outcomes in the treatment of posterior malleolus fracture. Patients with a Bartonicek type II fracture had a better functional outcome measured by the AOFAS score compared to other types. Bartonicek type IIa fractures got a higher AOFAS score and a lower incidence of osteoarthritis at the final follow-up than the other two subtypes. Classification of PMFs according to the Bartonicek classification was reliable. [ABSTRACT FROM AUTHOR]

Recombinant human prourokinase (rhPro-UK) is a novel thrombolytic that has been approved to treat patients with acute myocardial infarction. However, the safety and efficacy of intravenous rhPro-UK in patients with acute ischemic stroke (AIS) has not been well established. We aimed to investigate the safety and preliminary efficacy of rhPro-UK in patients with AIS in a multi-center phase IIa trial setting. One hundred nineteen patients within 4.5 h of AIS onset were enrolled in this randomized, open-label, 23-center phase IIa clinical trial. Patients were randomly assigned to 35 mg (n = 40) or 50 mg (n = 39) intravenous rhPro-UK or 0.9 mg/kg recombinant tissue plasminogen activator (r-tPA; n = 40). The primary endpoint was functional independence defined as a modified Rankin scale (mRS) score of 0 or 1 at 90 days. The secondary outcome was early neurological improvement defined as a reduction of ≥ 4 points on the National Institutes of Health Stroke Scale (NIHSS) score from baseline to 24 h after drug administration. Safety endpoints included death due to any cause, symptomatic intracerebral hemorrhage (sICH), and other serious adverse events (SAEs). The proportion of patients with an mRS score of ≤ 1 at 90 days did not differ significantly among three groups (35 mg rhPro-UK: 55.56% vs. 50 mg rhPro-UK: 57.89% vs. vs. r-tPA: 52.63%; P = 0.92). The rates of treatment response, referring to early neurological improvement, were similar among these three groups (36.11% vs. 31.58% vs. 28.95%, respectively; P = 0.85). There was no difference in mortality at 90 days or in the rate of other SAEs among the three groups. One patient in the 50 mg rhPro-UK group suffered sICH. While neither the primary efficacy outcomes nor safety profile differed significantly among the low, high rhPro-UK and control groups, it is a logical step to further test the low-dose rhPro-UK group versus the control group in a well-powered phase III study. Trial Registration:http://www.chictr.org.cn. Identifier: ChiCTR1800016519. Date of registration: June 6 2018. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings (TBCs), as effective thermal protection separating the substrate from high-temperature combustion gases and reducing the substrate temperature, are widely used in aerospace and other fields. During the service cycle of life, surface crack defects, interface disbond defects, and coating thickness changes are the main non-destructive testing (NDT) objects of TBCs. In this paper, the main active infrared thermography NDT techniques including the optical infrared thermography testing, the ultrasonic infrared thermography testing, and the microwave thermography testing techniques are reviewed. Through the summary and highlight of the detection principle and application status of these state-of-the-art techniques, the development of the active infrared thermography DNT technique in TBCs is presented. By comparing the sensitivity, advantages, and disadvantages of the techniques in TBC NDT, can provide a significant reference for researchers to choose an appropriate method. It is noteworthy that fabrication techniques of artificial defects for calibration of the active infrared thermography NDT technique inspection of TBC systems are also reviewed. Moreover, future trends in NDT for the TBC system based on the active infrared thermography NDT technique are also discussed and analyzed. [ABSTRACT FROM AUTHOR]

Preheating combustion as a novel generation of high-efficiency low-nitrogen combustion technology has profound significance for the clean and efficient utilization of pulverized coal. This paper mainly sheds light on the modification effect of changing the preheating temperature on pulverized coal after the preheating process with the premise of keeping the air equivalence ratio of the CFB unchanged. In this paper, the gas and solid conversion, the coal gas, preheated char conversion ratio, coal nitrogen conversion map, functional group conversion and crystal structure were compared and analyzed. The experimental results illustrated that the conversion ratio of carbon and nitrogen first increased and then decreased with the increase in the preheating temperature. Combining the coal–nitrogen conversion processes at different temperatures, the elements in the sample are more likely to convert to gas at about the preheating temperature of 869 °C. The preheating temperature has less influence on the carbon-containing functional groups, but has a greater influence on the oxygen-containing and nitrogen-containing functional groups. When the preheating temperature is 869 °C, the preheated char contains the more active sites and the greater reactivity. [ABSTRACT FROM AUTHOR]

With the adoption of 3D magnetic flux material and global ring windings, permanent magnet transverse flux machine (PMTFM) with soft magnetic composite cores can output relatively high torque density and only requires easy manufacturing process. For the PMTFM, there are two ways to put the permanent magnets (PMs). One is to put the PMs on the rotor side which is the traditional rotor PM TFM and the other is to put the PMs on the stator side which is the stator PM TFM. In this paper, the design methods and operation principle for both kinds of PMTFM will be presented and discussed. Four different TFMs (benchmark rotor PM TFM with NdFeB, stator PM TFM1 with ferrite magnet and stator PM TFM2 and TFM3 with NdFeB) have been designed, and the magnetic parameters and the main performance will be comparatively studied to show the main difference between stator PM TFM and rotor PM TFM. It can be seen that the stator PM TFM has better performance, and the stator PM TFM1 with ferrite magnets can have the same torque ability as that of the rotor PM TFM with NdFeB magnet but with very low material cost. With the adoption of NdFeB, the stator PM TFM2 can have two times higher torque ability than the rotor PM TFM, and the stator PM TFM2 can have the same torque ability as that of rotor PM TFM but with much smaller volume. As for the power factor and efficiency, it can be seen that the adoption of ferrite magnet will reduce both of them, and there is no much difference for the place where the PMs are installed. [ABSTRACT FROM AUTHOR]

High piezoelectric properties (d33 = 936 pC/N, d33* = 1015 pm/V, and kp = 0.701) are obtained from 960 °C sintered PNN–PZT piezoceramics by adding Li2CO3. The introduction of Li+ ions into PNN–PZT ceramics causes the phase shifts to the morphotropic phase boundary (MPB) region, which has not been reported for lead-based ferroelectrics. The Li+ ion doping shifts the phase to the MPB region, which grows the grains and decreases the activation energy (Ea) of the domain wall motion, making the domain grow more easily. Meanwhile, the domain indicates that Li+ ion doping allows the domain to rotate more easily; therefore, the domain size grows from the nanometer to the micrometer regime. Unlike reported nano-domains that lead to high piezoelectric activities, the MPB and larger micro-domains in the PNN–PZT ceramics are responsible for the high piezoelectric response. [ABSTRACT FROM AUTHOR]

Pb(Zr0.49Ti0.51)0.7(Zn1/3Nb2/3)0.3O3 (PZN–PZT) piezoceramics with Sr2+ ion substitution were sintered as low as 900°C by the solid-state reaction route. The specimens with various Sr2+ ion concentrations were compared according to their microstructure, phase structure, piezoelectricity, ferroelectricity, and dielectric relaxation. The substitution of the smaller Sr2+ ions for the A-site Pb2+ ions in the PZN–PZT system improves the electrical properties. The samples with 4 mol% Sr2+ substitutions have optimized piezoelectric properties (piezoelectric constant d33 = 496 pC/N, Curie temperature Tc = 244°C, electromechanical coupling coefficient kp = 0.58). Rietveld refinement from the XRD data reveals that the tetragonal lattice constants along with the a and c axes (a, c) for the PZN–PZT decrease with an increased Sr2+ substitution content. The c decreases faster than the a, which leads to decreased tetragonality (c/a), thus leading to shrinkage of the oxygen octahedrons in the ABO3 perovskite lattice. This lattice distortion facilitates mass transport, thereby increasing the bulk density and grain size of the perovskite PZN–PZT system. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) is the causative agent of porcine epidemic diarrhea, which can cause death in suckling piglets. Vaccines confer only partial protection against new mutant strains, whereas antibodies targeting virus-encoded proteins may be effective prophylactics. In this study, we constructed a recombinant single chain variable fragment (scFv) library from the spleens of two pigs immunized with a recombinant PEDV nucleocapsid (N) protein. Among the positive clones directed against PEDV N protein isolated from the library, four scFvs that showed higher affinity for N were functionally analyzed. These scFvs specifically bound to the PEDV N protein, but not to the transmissible gastroenteritis virus (TGEV) N protein. Their framework regions were highly conserved, whereas their complementarity-determining regions displayed clear diversity. An immunofluorescence assay showed the co-localization of the four scFvs with PEDV N protein in cells. They significantly suppressed PEDV replication, detected with reverse transcription (RT)-quantitative PCR (qPCR; P < 0.01). Two of them significantly reduced the viral titer at 48 hpi and 72 hpi (P < 0.05). In addition, they observably suppressed the production of viral protein at 72 hpi. The expression of interferons, interferon regulatory factor 3 (IRF3), and IRF7 was assessed with RT-qPCR, which indicated that PEDV dramatically suppressed the transcription of interferon-λ1 and IRF7 and that the scFvs significantly upregulated their expression (P < 0.05). These findings facilitated the investigation of the mechanism by which PEDV evaded the host immune response and suggested that these porcine scFvs were potential candidate agents for the prevention and treatment of porcine diarrhea caused by PEDV. Key points: • Four scFvs targeting PEDV N protein were generated from porcine spleens • These scFvs co-localized with PEDV N protein and suppressed PEDV replication • These scFvs significantly upregulated IFN-λ1 expression [ABSTRACT FROM AUTHOR]

Nowadays, the contamination of water due to oily waste is causing a serious threat to the environment. There is a need of a method that possesses a simple treatment route, low operational cost and high durability. The oil–water extractors, using magnetic-hydrophobic nanoparticles, act as an efficient method to separate the oil present in the waste water. In this study, thermal plasma system was developed which was found to be the effective and eco-friendly method for materials processing such as the production of superhydrophobic sphere-shaped nickel nanoparticles used oil/water separation process. The chemical composition, morphology and crystal structure of synthesized nanoparticles were investigated by XRD, TEMand XPS. The saturation magnetization (Ms) 45.26 emu/g, coercivity (Hc) 91.8 Oe and remanent magnetization (Mr) 6.65 emu/g of synthesized nickel nanoparticle at room temperature were investigated by using the VSM technique. Synthesized Nickel nanoparticles have high oil absorption capacity, rapid absorption rate and are ideal reusable for oil–water separation treatment. The nickel-coated sponge was found to be superhydrophobic and superoleophilic, respectively, with a water interaction angle of 150.8º for water and 0º for oil. Thus, the nanoparticles coated sponge has a separation efficiency of more than 98%, in separating both the heavy and light oils from oily-water. The separation recycling of the petrol/water mixture remained more than 96% even after 20 separation cycles. [ABSTRACT FROM AUTHOR]

Lead-free potassium sodium niobate [(K, Na)NbO3, KNN]-based ceramics have aroused great interest due to their excellent piezoelectricity and high Curie temperature. However, the deteriorative microstructure of KNN-based ceramics restricts their further developments. In this work, various kinds of oxide additives (Al2O3, Co2O3, Nb2O5, SnO2 and HfO2) are introduced into the KNN-based ceramics to increase the grain size and wipe the microcracks to improve their microstructures. Herein, large piezoelectric coefficient values (d33 ≈ 450–500 pC/N) and high Curie temperature values (TC ≈ 255–263 °C) together with high electromechanical coupling coefficient values (kp ≈ 0.50–0.56) are obtained in constructed R-O-T multiphase coexisted KNN-based ceramics. Moreover, the KNN ceramic with the addition of Al2O3 exhibits an optimal unipolar strain value (S = 0.124%) and a high inverse piezoelectric constant (d33* = 494 pm/V). We believe that our findings provide a simple, effective, and applicable approach to optimize the electrical performances of KNN-based system materials. [ABSTRACT FROM AUTHOR]

Yankuang coal with the high coking property is difficult to use through direct combustion. The main purpose of this paper is to study the combustion characteristics and NOx emissions of this type of coal using preheating combustion technology. The experimental results show that after the pulverized coal is preheated, the char residue characteristic is significantly reduced from 5 to 1. During the preheating process, the preheating temperature is stable at about 910°C, and the particle size of char after preheating is reduced, and the pore structure and specific surface areas are increased. The combustion temperature of preheated fuel is stable at around 1100°C, and the combustion efficiency can reach more than 99% under different conditions. Changing the structure of the secondary air nozzles during the preheating combustion process can influence the characteristics of emissions. The NOx emission of the central nozzle is about 112 mg/Nm3 lower than that of the annular nozzle. Changing the tertiary air distribution modes can reduce the final NOx emissions to 215 mg/Nm3 (@6%O2), and the corresponding conversion ratio of fuel N to the final NOx is 4.2%. The results of this experiment prove that the Yankuang coal can achieve stable combustion by preheating combustion technology, and this proposed a new way for the utilization of Yankuang coal. [ABSTRACT FROM AUTHOR]

Multitudinous topological configurations spawn oases of many physical properties and phenomena in condensed-matter physics. Nano-sized ferroelectric bubble domains with various polar topologies (e.g., vortices, skyrmions) achieved in ferroelectric films present great potential for valuable physical properties. However, experimentally manipulating bubble domains has remained elusive especially in the bulk form. Here, in any bulk material, we achieve self-confined bubble domains with multiple polar topologies in bulk Bi0.5Na0.5TiO3 ferroelectrics, especially skyrmions, as validated by direct Z-contrast imaging. This phenomenon is driven by the interplay of bulk, elastic and electrostatic energies of coexisting modulated phases with strong and weak spontaneous polarizations. We demonstrate reversable and tip-voltage magnitude/time-dependent donut-like domain morphology evolution towards continuously and reversibly modulated high-density nonvolatile ferroelectric memories. Experimentally manipulating bubble domains remains elusive especially in the bulk form of ferroelectrics. Here, the authors achieve self-confined bubble domains with multiple polar topologies in bulk Bi0.5Na0.5TiO3 ferroelectrics, demonstrating reversible and donut-like domain morphology evolution. [ABSTRACT FROM AUTHOR]

Li0.35+0.5xZn0.3TixFe2..35–1.5xO4 (x = 0–0.4) ferrites waere prepared via a solid-state method. XRD refinement results show that diamagnetic Ti4+ ions enter octahedral lattice and replace Fe3+ at B site, resulting in the redistribution of B sublattice magnetic moment and ultimately reducing saturation magnetization. This mechanism is analyzed from the perspective of ion occupying distribution and substitution law. Globus relation is used to qualitatively analyze the law of initial permeability change with temperature and titanium content, and the main influencing factors are revealed. The variation of initial permeability and permeability loss with frequency and its causes have been explored, which are attributed to domain wall displacement, domain rotation and various resonance effects, especially domain wall resonance. The dominant characteristics and main influencing parameters of the three types of power losses in different frequency bands were studied quantitatively, and the transition law of the main mechanism of power losses with the change of frequency was explored. The variation of dielectric properties with frequency, titanium content and temperature was studied and analyzed utilizing polarization mechanism and Koops model. [ABSTRACT FROM AUTHOR]

We report a facile approach to fabricating catalytic active palladium nanoparticles (NPs) immobilized on Fe-loaded carbonized bacterial cellulose nanofibers (Fe@CBC) for the catalytic reduction of toxic Cr(VI) to Cr(III) at room temperature. The formed nanofiber composites (Fe@CBC/Pd) was investigated by various physicochemical characterization and its catalytic activity, and reusability were evaluated as well. The results demonstrated that the Fe@CBC/Pd exhibited favorable catalytic activity for the reduction of Cr(VI) to Cr(III) in the presence of HCOOH. Moreover, the catalyst could be easily recovered from reaction system in a facile manner and recycled four times without obvious loss in activity. [ABSTRACT FROM AUTHOR]

Background: Increasing atmospheric [CO2] can increase photosynthesis and promote plant growth, consequently influencing nitrogen (N) cycling. Yet, there is no systematic information on the N response among different organs of japonica and indica rice genotypes to elevated [CO2] as affected by N application. To investigate the impacts of elevated [CO2] and N fertilization on N uptake and utilization of different genotypic rice (Oryza sativa L.) during grain filling, a free-air CO2 enrichment (FACE) experiment with indica cv. Liangyou 084 (IIY084) and japonica cv. Wuyunjing 23 (WYJ23) was conducted in Eastern China. Crops were exposed to ambient [CO2] and elevated [CO2] (200 μmol mol−1 above ambient) at two levels of N: control (0N) and 22.5 g N m−2 (normal N, NN), and they were sampled at 82 days after transplanting (DAT), 99 DAT, and maturity, respectively. Results: Under FACE, significant declines of N concentration in all tissues and the whole plants were observed with the greater decrease in leaves and stems at three stages. Positive responses of N use efficiency (NUE) to elevated [CO2] were recorded over the study period. The total N accumulation remained unchanged, while a large amount of N was partitioned to panicles at the expense of leaves and stems. As compared to WYJ23, greater N transportation from roots to aboveground, especially the panicles, was observed on IIY084 accompanied by higher panicle biomass (82 DAT and 99 DAT), N concentrations (maturity), and greater NUE for leaves through the study season. Across all [CO2] and cultivars, N fertilization increased N partitioning to leaves and stems while decreasing that to panicles. Additionally, N supply decreased NUE while stimulating N concentrations and N amounts of rice plants. Among all treatments, IIY084 had the highest N accumulation and allocation in panicles under elevated [CO2] in combination with N fertilizer at maturity. Conclusion: Data from this study were helpful for understanding the temporal N uptake and utilization of different rice genotypes as affected by N availability and suggest that IIY084 promises a considerable prospect for its grain yield and quality under future elevated atmospheric [CO2]. [ABSTRACT FROM AUTHOR]

0.96(K0.48Na0.52)(Nb1−xTax)O3–0.04(Bi0.5Ag0.5)ZrO3 lead-free ceramics were fabricated by solid-state reaction method. Because of the sensitive energy state in the coexisting phase structure, the addition of Ta5+ caused a palpable phase transformation from orthorhombic to tetragonal. At the same time, doping with (Bi0.5Ag0.5)ZrO3 could have effectively promoted densification and continued to enhance the piezoelectric and dielectric properties. Enhanced dielectric/ferroelectric properties were achieved for the ceramics which has a composition of (x = 0.15), and the ceramics expressed a high d33 of ∼ 373 pC/N with a TC of ∼ 255 °C. We believe that to design a binary phase system is a valid method to attain both large d33 and high TC in (K,Na)NbO3 (KNN)-based lead-free ceramics. [ABSTRACT FROM AUTHOR]

The Ca0.85(LiCe)0.075Bi4Ti4−xZnxO15 ceramics are prepared via solid‐state reaction method with lower sintering temperature. The influence of lower sintering temperatures (Ts) on structural and electrical properties is investigated. The repressed volatilization of Bi3+ reduces the impurity phase proportion and oxygen vacancies content in ceramics, which might lead to increased TC value (~ 800 °C), piezoelectric constant d33 value (20 pC/N), high resistivity (6.32 × 105 Ω·cm at 600 °C), and good thermal stability up to 600 °C. Therefore, the Zn-modified ceramics are perceived to be one of promising candidates for high-temperature piezoelectric devices. [ABSTRACT FROM AUTHOR]

Purpose: The stimulations of plant growth and soil nutrient availability by elevated carbon dioxide (CO2) concentration have been demonstrated in a series of experiments. However, the long-term response of microelement availability to elevated CO2 in paddy ecosystems without micronutrient fertilizer inputs is a matter of debate. Methods: Changes of microelement availability in paddy field were investigated by performing a situ experiment under the Free Air CO2 Enrichment (FACE) platform that lasted for a decade. Results: Elevated CO2 stimulated the dry matter production of rice and enhanced accumulation of iron (Fe), manganese (Mn), and zinc (Zn) in the stem and panicle. High CO2 concentration led to significant reductions in Fe, Mn, and Zn concentrations in soil solution at jointing and/or pre-filling stages, which were the vigorous growth periods for rice. A significant increase for Fe concentration in the surface water was observed at the vegetative stage, under elevated CO2 condition. Additionally, the contents of Zn extracted by diethylene triamine pentoacetic acid (DTPA) increased significantly in 0–10 cm soil treated by elevated CO2. Conclusions: Our study provides an improved understanding on changes of microelements availability in paddy field. The results demonstrated that high CO2 concentration promoted the accumulation of micronutrients in rice plants, but had no significant and positive effects on the availability of Fe and Mn in soil following a decade of CO2 fumigation. [ABSTRACT FROM AUTHOR]

In this work, we report a facile technique to prepare Ni nanoparticle-carbonized bacterial cellulose (Ni@CBC) composites by pyrolysis bacterial cellulose adsorbing corresponding nickel(II) nitrates. The introduction of carbonized bacterial cellulose served as a reductant for the conversion of Ni(II) to Ni as well as a support for Ni NPs to prevent the agglomeration. The synthesized composite material was tested as a catalyst to reduce toxic Cr(VI) to Cr(III) at room temperature, and UV–Vis spectrophotometry was employed to monitor the reduction process. According to the results, the Ni@CBC material showed good stability and highly catalytic activity at room temperature. [ABSTRACT FROM AUTHOR]

La2Ti1.96V0.04O7 (LTVO) ceramics with Ti4+ ions partially substituted by V5+ ions at B sites show excellent electrical properties. The dopant V5+ ions do not result in collapse of the cell layered structure, but they lead to the enhanced distortions of BO6 oxygen octahedrons. Impedance spectroscopy reveals that a certain number of defects are formed due to the substitution of Ti4+ ions by V5+ ions. Meanwhile, the concentration of oxygen vacancies is decreased compared to pure La2Ti2O7 (LTO) ceramics. The direct current resistivity of LTVO ceramics obtained from alternating current (AC) impedance fitting at 600°C is 1.3 × 106 Ω cm, which is more than five times of that of the pure LTO at the same temperature (2.2 × 105 Ω cm). The substitution of Ti4+ ions by V5+ ions greatly enhances the piezoelectric coefficient, d33 = 4.8 pC/N. Therefore, the doping of V5+ ions in the B sites of LTO ceramics should be a good choice for enhancing their piezoelectric properties and resistivity at high temperature regimes. [ABSTRACT FROM AUTHOR]

La2−xNdxTi2O7 (LNTO) ceramics with enhanced electrical properties have been prepared by traditional solid-state reaction method. The LNTO ceramics maintain a pure monoclinic phase at x ≤ 0.1. At x > 0.1, an orthorhombic phase Nd0.95TiO3 appears. Impedance spectra indicates that the substitution of La3+ ions by Nd3+ ions at A sites generates defects, resulting in the enhanced distortions of TiO6 octahedrons. The dielectric relaxation activation energy for these defects is 1.2 eV in temperature range T ≥ 650 ℃. The conductance activation energies are 0.3 eV and 1.0 eV for impure ions/thermions and defects/oxygen vacancies, respectively. The contributions of impure ions/thermions and defects/oxygen vacancies have been distinguished through the analysis of both normalized imaginary impedance Z″ and electrical modulus M″. Their impedance relaxation activation energies in normalized Z″ spectra are 1.3 eV and 0.8 eV, respectively. An enhanced piezoelectric coefficient (d33 = 2.8 pC/N) appears in La1.9Nd0.1Ti2O7 (LNTO-0.1) ceramics. [ABSTRACT FROM AUTHOR]

La2Ti2O7 (LTO) dry gel was obtained according to sol–gel technology. Considering that processing temperature could have effect on the microstructure and band gap of LTO, four temperature points, 500 °C, 850 °C, 1000 °C and 1200 °C were selected to dispose gel to acquire LTO powder. The results indicate that except the sample disposed at 500 °C, other three samples are univocal monoclinic structure with space group P21 which corresponds to the standard card 1950-ICSD. The crystallinity of LTO powders increases with the increase of processing temperature. The distortions of the LTO unit cell at a–b projection plane first decrease and then increase. Adopting the UV–visible reflection spectrums analysis, the band gaps of LTO powders disposed at 500 °C, 850 °C, 1000 °C and 1200 °C are 3.82 eV, 3.99 eV, 4.08 eV and 3.94 eV, respectively. [ABSTRACT FROM AUTHOR]

Free-air O3 enrichment was used to investigate the responses of different antioxidant mechanisms in different rice (Oryza sativa L.) cultivars – O3-sensitive hybrid indica (O3-S) cultivars and O3-tolerant conventional japonica (O3-T) cultivars across all growth stages. Elevated [O3] induced increases in reactive oxygen species (ROS) production in O3-S cultivars, which were more pronounced in the later growing stages. In O3-S cultivars, continuous O3 stress decreased catalase (CAT), peroxidase (POD) and glutathione peroxidase (GPX) activities, while in O3-T cultivars, short-term O3 stress decreased superoxide dismutase (SOD), CAT, POD and GPX activities. The same POD isozyme patterns were observed in both O3-S and O3-T cultivars, while SOD and APX isozymes varied by cultivar. The results suggest that O3 tolerance might be improved at different rice development stages through regulating the responses of antioxidant mechanisms to O3 stress. [ABSTRACT FROM AUTHOR]

Pulverized coal combustion technology with preheating solid fuel in a circulating fluidized bed was used for the combustion test of ultra-low volatile carbon-based fuel. This paper first validated the feasibility and advantages of applying the combustion technology to this kind of fuel. The carbon-based fuel could achieve a stable preheating process in this test system. After the preheating, the apparent sensible heat of the fuel was significantly increased. This provided a necessary condition for the stable ignition and efficient combustion of the carbon-based fuel in the post-combustion chamber. The relative proportions of CO, H2, and CH4 in preheated coal gas were very low, and the effect of high-temperature coal gas at the entrance of the post-combustion chamber was greatly impaired, indicating that the combustion process in post-combustion chamber was mainly the combustion of preheated char. At the same time, the strong reducing atmosphere in the circulating fluidized bed also facilitated the reduction of fuel-nitrogen into N2, which resulted in low NOx emissions. On this basis, with the combination of preheating combustion technology and air-staging combustion technology, the NOx emissions had drastically decreased when the burnout air distribution position moved down or varied from a single-layer distribution to a multi-layer distribution system. The lowest original NOx emissions were 90.6 mg/m3 (at 6% O2), and the combustion efficiency exceeded 97%, which ultimately achieved efficient and clean combustion of ultra-low volatile carbon-based fuel. [ABSTRACT FROM AUTHOR]

Bismuth titanate Bi4Ti3O12 (BIT) based lead-free piezoelectric ceramics with the formula Bi4Ti3-2xWxTaxO12 (abbreviated as BITWT-x, x = 0, 0.015, 0.03, 0.04, 0.045, 0.05) were fabricated by the conventional solid-state sintering method. The effect of W and Ta doping on the crystal structure and electrical properties of BITWT-x ceramics were investigated. BITWT-x ceramics had an orthogonal phase, and crystal structural distortion of W/Ta co-doped BITWT-x based ceramics was higher than that of BITWT-0 ceramics, which improved the ferroelectricity and the piezoelectric property. The ferroelectricity (Pr = 7.78 μC/cm2) of BITWT-0.03 ceramics was better than that (Pr = 0.84 μC/cm2) of BITWT-0 ceramics. The piezoelectric property (d33) was enhanced, and the highest d33 of BITWT-0.04 ceramics was 21.4 pC/N. Moreover, the d33 of the BITWT-x ceramics at 600 °C still kept 80% of its original d33 when the value of x was in the range of 0.03–0.045. Donor ions W6+ and Ta5+ reduced ionic conductivity (oxygen vacancies) and electron conductivity (holes), then increased the resistivity of BITWT-x ceramics (ρ400 °C = 1.82 × 108 Ω cm, x = 0.03). However, the enhanced effect reached a saturated state when x was 0.03. Thus, the BITWT-x ceramics were suitable for the high-temperature application. [ABSTRACT FROM AUTHOR]

A series of piezoelectric ceramics with the formula (1−x)Ca0.92(LiCe)0.04Bi2Nb2O9 + xCa2Nb2O7 (CBNLC–CNO-x, where x = 0, 0.05, 0.1, 0.15, 0.2) were prepared by a facile traditional solid-state reaction method. The phase structure, Raman spectra, microstructure, dielectric properties, electric properties, piezoelectric properties and thermal stabilities of the obtained CBNLC–CNO-x ceramics were studied. X-ray diffraction revealed that the obtained ceramics had a typical bismuth layer structure with secondary phases of Ca2Nb2O7. The Rietveld refinement and Raman spectra revealed a lattice distortion in the CBNLC–CNO-x ceramics, which influenced the piezoelectric properties. Scanning electron microscopy indicated that the grain size of the ceramics gradually decreased with increasing x value. The Curie temperature (Tc) of the ceramics was retained at an elevated temperature of approximately 926–940 °C and was close to that of pure CBN. The obtained ceramics showed great thermal stabilities, relative densities, dielectric properties and piezoelectric properties, which are beneficial for high-temperature applications. [ABSTRACT FROM AUTHOR]

Purpose: Elevated CO2 concentration (eCO2) may stimulate plant growth and influence the soil microbial community, but questions remain for whether microbial responses to elevated CO2 would vary by different CO2-responsive plants. We thus attempted to elaborate the changes of soil microbiome to different rice cultivars under the eCO2 condition. Materials and methods: Two rice cultivars, i.e., the CO2-tolerant cultivar, Wuyunjing23 (WYJ23), and the CO2-sensitive one, Yandao 6 (YD6), were grown under eCO2 and ambient CO2 (aCO2) conditions. The contents of dissolved organic carbon (DOC) and nitrogen (DON) in soil were measured. Real-time qualitative PCR (qPCR) and high-throughput sequencing techniques were employed to characterize the bacterial community. Furthermore, co-occurrence network analysis was applied to reveal the ecological interactions among bacterial taxa. Results and discussion: No significant differences were found among all treatments in terms of bacterial population, alpha-diversity indices, and bacterial community structure. However, the topological parameters of ecological networks highlighted the distinct co-occurrence patterns among treatments. YD6 under eCO2 led to more links, lower modularity, and greater centralization degree compared to that under aCO2. Opposite trends of those parameters were observed for WYJ23 under eCO2 compared to that under aCO2. Besides, more Proteobacteria and Acidobacteria served as keystone taxa in the CO2-sensitive cultivar treatments, compared to those in WYJ23, implying the different influences of rice cultivars on the microbial ecological network. Conclusions: Different rice cultivars under eCO2 did not influence the alpha- and beta-diversity of the soil bacterial community, but changed the co-occurrence network of the community. More attention should be paid to the assembly mechanisms of the soil microbial microbiome when evaluating the impacts of productive crops on the soil-plant ecosystem under the eCO2 condition. [ABSTRACT FROM AUTHOR]

High-Curie temperature complex piezoelectric ceramics (1 − x)CaBi4Ti4O15−xBi4Ti3O12 (short for (1 − x)CBT–xBIT) were fabricated by a solid-state reaction method. The evolution of the crystal structure and the electric property of (1 −x)CBT–xBIT ceramics were investigated. (1 − x)CBT–xBIT had an orthorhombic structure, and no impurity phases existed in. With the addition of BIT, the "CBT part" of 0.9CBT–0.1BIT ceramic had larger crystal structure distortion than CBT ceramics, especially the tilt from the c axis of the TiO6 octahedron layers. The crystal structure analysis indicated the enhanced octahedral tilt angle is beneficial to the ferroelectricicity of (1 − x)CBT–xBIT ceramics. The residual polarization Pr of (1 − x)CBT–xBIT ceramics (x = 0, 0.1, 1) were 1.97 µC/cm2, 6.33 µC/cm2 and 2.28 µC/cm2, respectively. And, the addition of the "BIT part" increased the concentration of oxygen vacancy and affected the conduction mechanism. Two anomalies (Tm1 and Tm2) existed in the temperature dependence of the dielectric behavior corresponding to the phase transition. Besides, Tm2 and d33 decreased with x increasing and Tm1 did not change markedly. Moreover, 0.9CBT–0.1BIT ceramic obtained the optimal piezoelectric constant (d33 = 15.2 pC/N) and dc resistivity (1.6×105 Ω·cm at 700 °C) compared to that (d33 = 15.2 pC/N, 3.1×104 Ω·cm at 700 °C) of CBT ceramics. [ABSTRACT FROM AUTHOR]

Transmissible gastroenteritis virus (TGEV) infection causes severe diarrhea in piglets and imposes a significant economic burden on pig farms. Single-chain fragment variable (scFv) antibodies effectively inhibit virus infection and could be a potential therapeutic reagent for preventing disease. In this study, a recombinant scFv antibody phage display library was constructed from peripheral blood lymphocytes of piglets infected with TGEV. The library was screened with four rounds of biopanning using purified TGEV antigen, and scFv antibodies that bound to TGEV were obtained. The scFv gene was subcloned into the pET-28a(+), and the constituted plasmid was introduced into Escherichia coli BL21 (DE3) for protein expression. All three scFv clones identified had neutralizing activity against TGEV. An immunofluorescence assay and western blot analysis demonstrated that two scFv antibodies reacted with the spike protein of TGEV. These results indicate that scFv antibodies provide protection against viral infection in vitro and may be a therapeutic candidate for both prevention and treatment of TGEV infection in swine. [ABSTRACT FROM AUTHOR]

The Ca1-2x(LiCe0.5Y0.5)xBi2Nb2O9 (CBNLCY-100x, x = 0-0.07) high-temperature ceramics were prepared by the conventional solid state reaction. The LiCeY substitution at A-site led an improvement of octahedral tilt angle in the a-c plane of CBNLCY-100x ceramics, which resulted in an enhanced piezoelectric constant. CBNLCY-6 ceramic with high Curie temperature (TC = 940 °C) had a high piezoelectric coefficient (d33) of 16.3 pC/N, even after annealing at 800 °C for 2 h, the d33 value of CBNLCY-6 ceramic still remained 92.6% of its original value. Furthermore, the dc conduction mechanism of the ceramics was studied. The oxygen vacancies played an important role in dc conduction mechanism at low temperature and the main conduction mechanism at high temperature was intrinsic conduction. The resistivity of CBNLCY-100x ceramics got highest value at x = 0.01 and the resistivity of CBNLCY-1 ceramic enhanced one order of magnitude compared with undoped CaBi2Nb2O9 ceramic. These results suggest that the CBNLCY-6 ceramic is a promising candidate material for ultra-high temperature applications. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus-induced bovine mastitis causes significant losses to the dairy industry and available vaccines do not confer adequate protection. As a more attractive alternative, we propose the use of antibody (Ab) therapy. In our previous study, we constructed a bovine single-chain variable fragment (scFv) Ab phage display and successfully obtained scFvs that bound to S. aureus antigens with high affinity. Here, we describe a novel Ab against S. aureus (scFv-Fc Ab). To construct the scFv-Fc Ab, the scFv Ab was genetically fused to the Fc fragment of a bovine IgG1 Ab. Western blot analysis showed that the bovine scFvs-Fc Abs were successfully expressed with horseradish peroxidase-conjugated goat-anti-bovine IgG (Fc) Ab in Escherichia coli cells. The purified bovine scFvs-Fc Abs had good binding activity to S. aureus and effectively inhibited the bacterial growth in culture medium and bovine scFvs-Fc Abs enhanced phagocytosis of S. aureus by neutrophils isolated from peripheral blood in a dose-dependent manner. In the experiment of bovine scFvs-Fc Abs for the treatment of S. aureus-induced bovine mastitis, the total effective percentage reached 82% (9/11). These novel bovine scFvs-Fc Abs may be useful as therapeutic candidates for the prevention and treatment of S. aureus-induced bovine mastitis. [ABSTRACT FROM AUTHOR]

Aurivillius phase [Ca0.6(Na0.5Bi0.5)0.4]1−x(LiCe)x/2Bi2Nb2O9 (CNBNLC-100x, x = 0, 0.02, 0.04, 0.06, 0.08, 0.10, 0.12) ceramics were prepared by the conventional solid state method. The LiCe substitution induced structural distortion and orthorhombic distortion of CNBNLC-100x ceramics which influenced piezoelectric activities and Curie temperature, respectively. The results implied that the more structural distortion of lattice leads to higher piezoelectricity. CNBNLC-8 ceramics with ultrahigh TC of 904 °C had a high piezoelectric activity of 17.6 pC/N, even after annealing at 600 °C for 2 h, the d33 value of CNBNLC-8 ceramics still retained 62.5% of its original value. Ce4+ as donor dopant, the dc resistivity of CNBN ceramics increased with the substitution of Ce4+ for Ca2+. At high temperature region, the extrinsic conductivity changes of the ceramics from p-type to n-type with the increase of Ce4+ doping amount. Further investigation demonstrated that the ac conductive process of ceramics referred to three different mechanisms. The main conduction mechanisms were considered as first-order ionization of oxygen vacancies, second- order ionization of oxygen vacancies and intrinsic dc conductivity at three temperature regions, respectively. All these good electrical properties provided the LiCe doped CNBN ceramics with a large potentiality for high-temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]

Experimental studies were carried out to find the difference of preheating characteristics of Datong coal in O2/CO2 and air atmospheres by a circulating fluidized bed. It is found that pulverized coal could be both steadily preheated to above 800°C in the two different atmospheres, but the temperature distribution was more uniform along the riser in O2/CO2 atmosphere. During the preheating, the content of CO in the flue gas can reach 12.32% under the O2/CO2 atmosphere, far higher than that in air (5.94%). Simultaneously, the conversion rate of fixed carbon was higher in O2/CO2 atmosphere compared with that in air. It can be inferred the higher oxygen concentration and higher partial pressure of CO2 have greatly accelerated the gasification reaction. The BET analysis indicated a number of large pores were transformed into micropores during the preheating progress, and the major contributors for overall pore volume of chars and specific surface area are the micro-pores and the mesopores with diameter ranging from 2 nm to 10 nm. The inner pore structure was more developed in O2/CO2 atmosphere. [ABSTRACT FROM AUTHOR]

The influence of Pb(Ni1/3Nb2/3)O3 (PNN) on the structure and electronic properties of 0.36BiScO3-0.64PbTiO3 (BSPT) piezoelectric ceramics which were synthesized by the conventional solid-state synthesis have been systematically investigated. It was found that the ceramics with lower PNN content exhibited normal ferroelectric behavior. However, the ceramics showed a diffused phase transition characteristic as PNN content increased. The BSPT-xPNN ceramics when x = 1% showed enhanced piezoelectric properties with piezoelectric constant d33 = 531 pC/N, planar electromechanical coupling factors kp = 0.58, remnant polarization Pr = 34.6 µC/cm2, and coercive field Ec = 12.0 kV/cm with a high Curie temperature TC = 417 °C. The enhanced piezoelectric/ferroelectric properties and higher Curie temperature of the BSPT-xPNN ceramics are mainly ascribed to the lower level of the tetragonality and lower tolerance factor. As result, this material system is one of the promising candidates for high temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]

In this work, the elastic constants of 3D four directional cylindrical braided composite shafts were predicted using analytical and numerical methods. First, the motion rule of yarn carrier of 3D four directional cylindrical braided composite shafts was analyzed, and the horizontal projection of yarn motion trajectory was obtained. Then, the geometry models of unit-cells with different braiding angles and fiber volume contents were built up, and the meso-scale models of 3D cylindrical braided composite shafts were obtained. Finally, the effects of braiding angles and fiber volume contents on the elastic constants of 3D braided composite shafts were analyzed theoretically and numerically. These results play a crucial role in investigating the mechanical properties of 3D 4-directional braided composites shafts. [ABSTRACT FROM AUTHOR]

We investigated the effect of excessive alkali metals on sintering character, phase structure, dielectric, piezoelectric and ferroelectric properties in KNN-based ceramics thoroughly. The 0.96(K0.48Na0.52)1+xNb0.93Sb0.02Ta0.05O3-0.04Bi0.5(K0.12Na0.88)0.5ZrO3 [(KN)xNTS-BKNZ] lead-free piezoelectric ceramics were prepared by conventional solid-state reaction method. The sintering temperature of (KN)xNTS-BKNZ ceramics increases gradually while the sintering temperature zone becomes narrow with the increasing x value. For the composition of x > 0.03, the grains could not grow in all sintering temperature. The coexistence system of rhombohedral and tetragonal phases has been found in (KN)xNTS-BKNZ ceramics and the TR−T, TC, d33, and εr show a upward tendency with the increasing x when 0 ≤ x ≤ 0.03. The maximal piezoelectric coefficient d33 of 415 pC/N was obtained at x = 0.03. In addition, these ceramics presented good temperature stability. This study exhibits that excessive alkali metals influence sintering character and electrical properties on KNN ceramics deeply. It was believed that this work would be helpful for further understanding the effect of excessive alkali metals on sintering behavior and electric properties in KNN-based ceramics. [ABSTRACT FROM AUTHOR]

The torsional bulking behavior of 3D 4-directional braided composites shafts was analyzed in this work. First, the unit cell models of 3D 4-directional braided composites shafts with different braiding angles and fiber volume fraction were built up. Then, the elastic parameters of 3D 4-directional braided composites shafts were predicted using the unit cells under different boundary conditions. Finally, the torsional bulking eigenvalues and bulking modes of the composites shafts were obtained by numerical simulation, and the effects of braiding angle and fiber volume fraction on the torsional bulking behavior of 3D 4-directional braided composites shafts were analyzed. The simulation results show that the bulking eigenvalues increase with the increase of braiding angle and fiber volume fraction. This work will play an important role in the design of 3D 4-directional braided composites shafts. [ABSTRACT FROM AUTHOR]

As a novel three dimensional digital image correlation (3D DIC) method, the bi-prism-based single lens (BSL) 3D DIC method has been proposed and developed in recent years. Making use of a bi-prism, this method is able to perform a 3D DIC measurement using only a single camera. Thus, the integration level of a BSL 3D DIC system could be much higher than that of the double-camera 3D DIC system. In this paper, using a small-angle bi-prism and a camera with a longer focal length, a special BSL 3D DIC system with a long working distance is designed for measurements in extreme environments. The principle of the system is first studied, and practical methods are then proposed for the system set-up and the determination of system parameters. Then, feasibility of the measurement system is verified by out-of-plane rigid-body translation tests. Finally, the BSL 3D DIC system is proven to be capable of combining with a high-temperature testing instrument to perform deformation tests in a high-temperature environment of up to 1500°C. [ABSTRACT FROM AUTHOR]