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Capacitive deionization has attracted wide concern on accountof its high energy efficiency, low manufacturing cost and environmental friendliness. Nevertheless, the development of capacitive deionization is still impeded because of the scarcity of suitable electrode materials with superior performance. Herein, we successfully prepared the two-dimensional (2D) titanium carbide (Ti

MXene has attracted a wide spread attention as promising supercapacitor electrode materials owing to excellent electronic conductivity and reversible surface redox capability. In fact, the supercapacitor performance strongly relies onsurface terminations of MXene. However, regulating the types of surface terminations for enhancing the electrochemical performance of MXene is still one of major challenge. Herein, we successfully prepared a MXene containing iodine terminations (I-Ti

Due to the strong background noise and the acquisition system noise, the useful characteristics are often difficult to be detected. To solve this problem, sparse coding captures a concise representation of the high-level features in the signal using the underlying structure of the signal. Recently, an Online Convolutional Sparse Coding (OCSC) denoising algorithm has been proposed. However, it does not consider the structural characteristics of the signal, the sparsity of each iteration is not enough. Therefore, a threshold shrinkage algorithm considering neighborhood sparsity is proposed, and a training strategy from loose to tight is developed to further improve the denoising performance of the algorithm, called Variable Threshold Neighborhood Online Convolution Sparse Coding (VTNOCSC). By embedding the structural sparse threshold shrinkage operator into the process of solving the sparse coefficient and gradually approaching the optimal noise separation point in the training, the signal denoising performance of the algorithm is greatly improved. VTNOCSC is used to process the actual bearing fault signal, the noise interference is successfully reduced and the interest features are more evident. Compared with other existing methods, VTNOCSC has better denoising performance.

The production capacity of indirect coal liquefaction (ICL) in use in China has reached a level of 8 million t/a, which corresponds to a carbon footprint of >60 million t/a. ICL is facing mountainous pressure to reduce its carbon emissions when its development is planned with carbon neutrality as a background objective. This paper studies the pathways that can lead to carbon neutrality for ICL in China, constructing four carbon-neutral pathways for ICL systems with the introduction of green hydrogen, biomass as feedstock and with CCS (carbon capture and storage), which can reduce significant carbon emissions from coal-gasification and water–gas shift processes. The carbon-neutral biomass is used to replace some coal as co-feed to gasification and combustion, leading to reduced carbon emissions as well. Calculations and economic analyses are performed on different carbon-reduction pathways using a carbon-neutral ICL system on a 1 million t/a scale as an example. The results are that the pathway of direct coal substitution with biomass is the lowest carbon-reduction route at RMB 31~125/t CO2, substitution with green hydrogen costs the highest at RMB 84~422/t CO2 and CCS costs are in the middle at RMB 96~148/t CO2. Each pathway has its pros and cons, and a combination of the three may be used for the best outcome. Furthermore, a comprehensive study and systematic summation of the critical technological processes and their underlying challenges for carbon-neutral ICL together with direction for a technological breakthrough are presented. These ICL carbon-reduction pathways presented in this paper are capable of realizing an integrated development between fossil and renewable energy sources, helping the carbon-intense coal-chemical industries to achieve their goals of carbon peak and carbon neutrality.

MXene has drawn considerable attention in energy storage due to particular physicochemical properties. At present, among most near-ambient temperature preparation methods, water is usually served as the main solvent. However, MXene is usually subjected to fast structural degradation on account of water molecules attacking in aqueous solution. Herein, we report a novel water-free etching strategy for synthesizing few-layered Ti

As the demand for green energy with high efficiency and low carbon dioxide (CO2) emissions has increased, solid oxide fuel cells (SOFCs) have been intensively developed in recent years. Integrated gasification fuel cells (IGFCs) in particular show potential for large-scale power generation to further increase system efficiency. Thus, for commercial application of IGFCs, it is important to design reliable multi-stacks for large systems that show long-term stability and practical fuel gas for application to industrial equipment. In this work, a test rig (of a 5 kW SOFC system, with syngas from industrial gasifiers as fuel) was fabricated and subjected to long-term tests under high fuel utilization to investigate its performance. The maximum steady output power of the system was 5700 W using hydrogen and 5660 W using syngas and the maximum steady electrical efficiency was 61.24% while the fuel utilization efficiency was 89.25%. The test lasted for more than 500 h as the fuel utilization efficiency was larger than 83%. The performances of each stack tower were almost identical at both the initial stage and after long-term operation. After 500 h operation, the performances of the stack towers decreased only slightly under lower current and showed almost no change under high current. These results demonstrate the reliability of the multi-stack design and the prospect of this SOFC power-generation system for further enlarging its application in a MWth demonstration.

Aqueous zinc ion batteries have attracted extensive concern as a promising candidate for large-scale energy storage because of their high theoretical specific capacity, low cost and inherent safety. However, the lacking of applicable cathode materials with outstanding electrochemical performance have severely hindered the further development of aqueous zinc ion batteries. Herein, we report a hierarchical accordion-like manganese oxide@carbon (MnO@C) hybrid with strong interaction heterointerface and comprehensively inquire into its electrochemical performance as cathode materials for aqueous zinc ion batteries. The unique hierarchical accordion-like layered structure coupling with strong interaction heterointerface between small MnO and carbon matrix efficaciously improve the ion/electron transfer process and enhance structure stability of the MnO@C hybrid. Benefitting from these unique advantages, the MnO@C hybrid bestows excellent specific capacity of 456 mAh g

The rub-impact fault, which occurs in the aeroengine, can cause frequency modulation (FM) in its vibration signal. Oscillated instantaneous frequency (IF) is a phenomenon of such a modulation mode, which carries critical fault information from the aeroengine. In this paper, by using Variational Mode Decomposition (VMD), the vibration signal can be decomposed into several signal components. Two-layer Singular Value Decomposition (SVD) is utilized to reduce the signal noise of each signal component and instantaneous frequency of each signal component. The intra–wave FM feature of the signal are presented through the Hilbert transform (HT) analysis. The proposed method is validated with numerical simulation and then demonstrated on aeroengine data with the rub-impact fault. The proposed method is suitable for the analysis of modulated signals and is a valid tool for detecting the rub-impact faults in aeroengines.

Aqueous zinc-ion batteries receive more and more attentions on account of their low cost, high theoretical density and inherent safety. Nevertheless, the lack of suitable cathode materials with excellent performance still severely impedes the development of aqueous zinc-ion batteries. Herein, an in-situ electrochemical induction strategy is developed to prepare hollow nanotube-like amorphous vanadium oxide and carbon (a-V

Mobile edge computing (MEC) provides physical resources closer to end users, becoming a good complement to cloud computing. The booming MEC brings many multiobjective optimization problems. The paper proposes a multiobjective optimization (MOO) algorithm called SAMOACOMV, which provides a new choice for solving MOO problems of MEC. We improve the ACOMV algorithm that is only suitable for solving mixed-variable single-objective optimization (SOO) problems and propose a MOACOMV algorithm suitable for solving mixed-variable MOO problems. And aiming at the dependence of MOACOMV algorithm performance on parameter setting, we proposed the SAMOACOMV algorithm using a self-adaptive parameter setting scheme. Furthermore, the paper also designs some mixed-variable MOO benchmark problems for the purpose to test and compare the performance of the SAMOACOMV algorithm. The experiments indicate that the SAMOACOMV algorithm has excellent comprehensive performance and is an ideal choice for solving mixed-variable MOO problems.

Human immunodeficiency virus (HIV) vaccines have not been successful in clinical trials. Dimeric IgA (dIgA) in the form of secretory IgA is the most abundant antibody class in mucosal tissues, making dIgA a prime candidate for potential HIV vaccines. We coupled Positron Emission Tomography (PET) imaging and fluorescent microscopy of 64Cu-labeled, photoactivatable-GFP HIV (PA-GFP-BaL) and fluorescently labeled dIgA to determine how dIgA antibodies influence virus interaction with mucosal barriers and viral penetration in colorectal tissue. Our results show that HIV virions rapidly disseminate throughout the colon two hours after exposure. The presence of dIgA resulted in an increase in virions and penetration depth in the transverse colon. Moreover, virions were found in the mesenteric lymph nodes two hours after viral exposure, and the presence of dIgA led to an increase in virions in mesenteric lymph nodes. Taken together, these technologies enable in vivo and in situ visualization of antibody-virus interactions and detailed investigations of early events in HIV infection., Author summary Vaccines provide protection in humans by eliciting the production of antibodies when exposed to a specific pathogen. Currently, an effective human immunodeficiency virus (HIV) vaccine does not exist. Since the beginning of the HIV epidemic, approximately 38 million people have died, creating the need to develop an HIV vaccine. The most common antibody in the organs that are exposed to HIV is dimeric IgA (dIgA). Here, we used multiple imaging techniques to determine how HIV travels throughout the colon once introduced into the body and how dIgA influences HIV movement in the rectum. We found that dIgA increased the amount of HIV found in the colon, the distance it travelled, and the depth into tissues that HIV penetrated. dIgA also increased the amount of HIV in the mesenteric lymph nodes two hours after viral exposure. Our study shows these imaging technologies can be used to examine interactions between viruses and antibodies in early HIV infection in the natural context of the anatomy and physiology of the rhesus macaque model.

The flame fuel cell is a novel kind of fuel cell that directly combines a fuel-rich flame and solid oxide fuel cells together. Because of their simple setup, low cost, quick start-up and shut-down as well as no extra thermal management, flame fuel cells have great potential in micro-combined heat and power systems and portable applications. However, the conventional solid oxide fuel cell configurations including planar ones and tubular ones, may cause some problems when used in flame fuel cells such as thermal stress, secondary flame front, and difficulty for mass production. To solve these problems, a newly developed flat-chip solid oxide fuel cell is proposed to be used in the flame fuel cell in this study. Combining the merits of both planar and tubular solid oxide fuel cells, the flat-chip fuel cell is advantageous for its simple fabrication technology, good thermal shock resistance and feasibility to scale up. A flat-chip solid oxide fuel cell is fabricated and then integrated with a catalytically enhanced porous media combustor, demonstrating a novel flat-chip flame fuel cell system. The heating time for the flat-chip solid oxide fuel cell by the fuel-rich flame is less than 10 min from room temperature to 800 °C, with a temperature change rate of 5 °C/s in the first stage. The start-up time of the flat-chip flame fuel cell is less than 10 s. When the gas velocity is 6.0 cm/s and the equivalence ratio is 2.0, a peak power density of 179 mW/cm2 is obtained for a single cell. Although there exists a remarkable temperature gradient, a small current degradation of 0.01 A/h is observed after a constant-voltage discharging at 0.5 V for 8 hrs. In addition, the flat-chip solid oxide fuel cell can be further scaled up in dimension, resulting in higher fuel utilization of flame fuel cell.

The flame fuel cell (FFC) is advantageous for its simple setup, quick start-up, and high fuel flexibility. However, one important drawback of the FFC is its relatively low electrical efficiency, which is mainly limited by the reforming efficiency of the burner and fuel utilization. In this study, to increase the reforming efficiency and fuel utilization, a catalytically enhanced porous media combustor was integrated with a micro-tubular solid oxide fuel cell stack. The second layer of the porous material was impregnated with 0.5 wt% Rh, improving the reforming efficiency from 49% to 64.8%. The fuel utilization was demonstrated to be 32.6% when the equivalence ratio was 1.6 and the inlet flow rate of combustion products to the anode of the stack was 200 mL min−1. The effects of the equivalence ratio and anode gas flow rate on the electrochemical performance and efficiency were investigated. A power density of 72.9 mW cm−2 and a total electrical efficiency of 12.9% were obtained at a voltage of 0.76 V and an equivalence ratio of 2.4.

Syngas production by the partial oxidation reforming of methane is a promising technology with a simple setup and quick dynamic response, which has great potential for application in small-scale fuel cells and portable power units. In this study, a catalytically enhanced porous media combustor for partial oxidation reforming is designed and tested. In the combustor, fuel-rich combustion in porous media and catalytic partial oxidation are integrated, benefitting from the merits of both technologies. Without external heat source, the combustor is directly ignited with a stoichiometric gas mixture during the cold startup process, and then adjusted to the partial oxidation conditions. Three zones, a preheating zone, an oxidation zone involving exothermic reactions, and a reforming zone involving endothermic reactions, are observed, which significantly affect the temperature profile in the axial direction. Considering both the methane conversion and reforming efficiency, the optimal equivalence ratio range for self-sustained operation is found to be 2.0–2.4. At an equivalence ratio of 2.0, the effect of the gas velocity on the temperature profile and gas composition of products are studied experimentally. At an equivalence ratio of 2.4 and a gas velocity of 0.13 m/s, the reforming efficiencies of the reactor reach 61.5% and 64.8% when 0.5 wt% Pd and 0.5 wt% Rh, respectively, are introduced to the second layer of the porous media. The carbon deposition at different axial positions of the reactor is analyzed, and the results indicate that carbon deposition by methane pyrolysis in the high-temperature oxidation zone is the dominating cause of carbon deposition. A re-ignition process at stoichiometric condition is helpful for the elimination of carbon.

Rolling bearings are a widely used component in rotating machinery, and deterioration of their performance may lead to machine breakdown and accidents. However, because rolling bearings often work under time-varying working conditions it is a great challenge to accurately separate fault features from working condition features. This paper presents a new neural network framework for variable speed fault diagnosis. The proposed neural network can eliminate the influence of condition information during training. Firstly, samples of the same category under different working conditions are distinguished. Secondly, a projection matrix is designed at the last layer of the neural network to project the features extracted through forward propagation to a hyperplane of the same latitude, so that the fault features are more obvious. Finally, a network model that can distinguish fault features from working conditions is obtained through back propagation training. In addition, we propose a multi-loss function, which can reduce the within-class distance and enlarge the between-class distance. The method is validated using bearing datasets under time-varying rotation speeds. The results show that our method has higher accuracy with a simple structure, and is a great improvement on the traditional method of bearing fault diagnosis.

Multi-objective optimization (MOO) problems are often encountered in engineering calculations. Commonly used MOO algorithms include classical algorithms and modern heuristic algorithms. Modern heuristic algorithms can find the Pareto solution set, and are used most widely at present. This paper improves the ACO MV algorithm which is only suitable for solving mixed-variable single-objective optimization (SOO) problems, and proposes a MOACO MV algorithm suitable for solving mixed-variable MOO problems. And aiming at the dependence of MOACO MV algorithm performance on parameter setting, a SAMOACO MV algorithm using self-adaptive parameter setting scheme is proposed. Furthermore, the paper also designs one mixed-variable MOO benchmark for purpose to test and compare the performance of SAMOACO MV algorithm. The experiments indicate that SAMOACO MV algorithm has excellent comprehensive performance and is an ideal choice for solving mixed variable MOO problems.

With increasing demand of green energy supply with high efficiency and low CO2 emission, Solid oxide fuel cell (SOFC) has been intensively developed in recent years. And the integration of gasification with fuel cell (IGFC) shows potential in large scale power generation to further increase the system efficiency. Reliable design of multi-stacks for large system and long term stability of stacks with practical fuel gas from industrial equipment are the key for commercial application of IGFC. In this work, a test rig of 5kW SOFC system was fabricated using practical syngas from industrial gasifiers as fuel and long term test under high fuel utility was conducted to investigate the system performance. The results show that the maximum steady output power of system is 5700W for hydrogen case and 5660W for syngas case, and the maximum steady electrical efficiency is 61.24% while the fuel utility efficiency is 89.25%. The test lasted for more than 500h as the fuel utility efficiency was larger than 83%. The performances of each stack tower are almost identical at both initial stage and after long term operation. After 500h operation, the performances of stack towers just slight decrease under lower current and almost not change under higher current. Therefore, the results illustrate that the reliability of multi-stacks design and the prospect of SOFC power generation system for further enlarging its application in a MWth demonstration.

This study demonstrates a module that consists of solid oxide fuel cell (SOFC) with flat-chip configuration and a catalytic partial oxidation (CPOX) reformer. The CPOX reformer uses Rh supported by Al2O3 as catalyst and functions effectively. The optimized temperature of CPOX reformer is 800 °C and the optimal C/O ratio to operate the reformer is ca. 0.8 where the maximum reforming efficiency, i.e. 86.1% can be obtained. The CPOX reformer can be coupled with a flat-chip SOFC, which is advantageous for its good thermal shock resistance, quick startup and good response characteristics. The flat-chip SOFC is able to function with a temperature difference over 850 °C across the cell itself and can survive the harsh tests of rapid thermal cycling with the temperature change rate well above 200 °C·min−1, and repetitive redox cycling at least 23 times.

Antigen accumulation in lymph nodes (LNs) is critical for vaccine efficacy, but understanding of vaccine biodistribution in humans or large animals remains limited. Using the rhesus macaque model, we employed a combination of positron emission tomography (PET) and fluorescence imaging to characterize the whole-animal to tissue-level biodistribution of a subunit vaccine comprised of an HIV envelope trimer protein nanoparticle (trimer-NP) and lipid-conjugated CpG adjuvant (amph-CpG). Following immunization in the thigh, PET imaging revealed vaccine uptake primarily in inguinal and iliac LNs, reaching distances up to 17 cm away from the injection site. Within LNs, trimer-NPs exhibited striking accumulation on the periphery of follicular dendritic cell (FDC) networks in B cell follicles. Comparative imaging of soluble Env trimers (not presented on nanoparticles) in naive or previously-immunized animals revealed diffuse deposition of trimer antigens in LNs following primary immunization, but concentration on FDCs in pre-immunized animals with high levels of trimer-specific IgG. These data demonstrate the capacity of nanoparticle or “albumin hitchhiking” technologies to concentrate vaccines in genitourinary tract-draining LNs, which may be valuable for promoting mucosal immunity.

We previously associated a missense mutation of the tc0668 gene of serial in vitro -passaged Chlamydia muridarum , a murine model of human urogenital C. trachomatis , with severely attenuated disease development in the upper genital tract of female mice. Since these mutants also contained a TC0237 Q117E missense mutation that enhances their in vitro infectivity, an effort was made here to isolate and characterize a tc0668 single mutant to determine its individual contribution to urogenital pathogenicity. Detailed genetic analysis of C. muridarum passages revealed a truncated variant with a G216* nonsense mutation of the 408-amino-acid TC0668 protein that does not produce a detectable product. Intracellular growth and infectivity of C. muridarum in vitro remain unaffected in the absence of TC0668. Intravaginal inoculation of the TC0668 null mutant into C3H/HeJ mice results in a typical course of lower genital tract infection but, unlike a pathogenic isogenic control, is unable to elicit significant chronic inflammation of the oviduct and fails to induce hydrosalpinx. Thus, TC0668 is demonstrated as an important chromosome-encoded urogenital pathogenicity factor of C. muridarum and the first with these characteristics to be discovered for a Chlamydia pathogen.

Worldwide, most new HIV infections occur through mucosal exposure. Immunoglobulin M (IgM) is the first antibody class generated in response to infectious agents; IgM is present in the systemic circulation and in mucosal fluids as secretory IgM. We sought to investigate for the first time the role of IgM in preventing AIDS virus acquisition in vivo.Recombinant polymeric monoclonal IgM was generated from the neutralizing monoclonal IgG1 antibody 33C6-IgG1, tested in vitro, and given by passive intrarectal immunization to rhesus macaques 30 min before intrarectal challenge with simian-human immunodeficiency virus (SHIV) that carries an HIV-1 envelope gene.In vitro, 33C6-IgM captured virions more efficiently and neutralized the challenge SHIV with a 50% inhibitory molar concentration (IC50) that was 1 log lower than that for 33C6-IgG1. The IgM form also exhibited significantly higher affinity and avidity compared with 33C6-IgG1. After intrarectal administration, 33C6-IgM prevented viremia in four out of six rhesus macaques after high-dose intrarectal SHIV challenge. Five out of six rhesus macaques given 33C6-IgG1 were protected at a five times higher molar concentration compared with the IgM form; all untreated controls became highly viremic. Rhesus macaques passively immunized with 33C6-IgM with breakthrough infection had notably early development of autologous neutralizing antibody responses.Our primate model data provide the first proof-of-concept that mucosal IgM can prevent mucosal HIV transmission and have implications for HIV prevention and vaccine development.

Intravaginal infection with Chlamydia muridarum in mice can ascend to the upper genital tract, resulting in hydrosalpinx, a pathological hallmark for tubal infertility in women infected with C. trachomatis . Here, we utilized in vivo imaging of C. muridarum infection in mice following an intravaginal inoculation and confirmed the rapid ascent of the chlamydial organisms from the lower to upper genital tracts. Unexpectedly, the C. muridarum -derived signal was still detectable in the abdominal area 100 days after inoculation. Ex vivo imaging of the mouse organs revealed that the long-lasting presence of the chlamydial signal was restricted to the gastrointestinal (GI) tract, which was validated by directly measuring the chlamydial live organisms and genomes in the same organs. The C. muridarum organisms spreading from the genital to the GI tracts were detected in different mouse strains and appeared to be independent of oral or rectal routes. Mice prevented from orally taking up excretions also developed the long-lasting GI tract infection. Inoculation of C. muridarum directly into the upper genital tract, which resulted in a delayed vaginal shedding of live organisms, accelerated the chlamydial spreading to the GI tract. Thus, we have demonstrated that the genital tract chlamydial organisms may use a systemic route to spread to and establish a long-lasting infection in the GI tract. The significance of the chlamydial spreading from the genital to GI tracts is discussed.

Hydrosalpinx induction in mice by Chlamydia muridarum infection, a model that has been used to study C. trachomatis pathogenesis in women, is known to depend on the cryptic plasmid that encodes eight genes designated pgp1 to pgp8 . To identify the plasmid-encoded pathogenic determinants, we evaluated C. muridarum transformants deficient in the plasmid-borne gene pgp3 , - 4 , or - 7 for induction of hydrosalpinx. C. muridarum transformants with an in-frame deletion of either pgp3 or - 4 but not - 7 failed to induce hydrosalpinx. The deletion mutant phenotype was reproduced by using transformants with premature termination codon insertions in the corresponding pgp genes (to minimize polar effects inherent in the deletion mutants). Pgp4 is known to regulate pgp3 expression, while lack of Pgp3 does not significantly affect Pgp4 function. Thus, we conclude that Pgp3 is an effector virulence factor and that lack of Pgp3 may be responsible for the attenuation in C. muridarum pathogenicity described above. This attenuated pathogenicity was further correlated with a rapid decrease in chlamydial survival in the lower genital tract and reduced ascension to the upper genital tract in mice infected with C. muridarum deficient in Pgp3 but not Pgp7. The Pgp3-deficient C. muridarum organisms were also less invasive when delivered directly to the oviduct on day 7 after inoculation. These observations demonstrate that plasmid-encoded Pgp3 is required for C. muridarum survival in the mouse genital tract and represents a major virulence factor in C. muridarum pathogenesis in mice.