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Li–S batteries with a high theoretical specific capacity and energy density are poised to be one of the most promising next generation systems; however, the complex preparation process of the cathode material and low cyclic stability, particularly at high current density, have limited their practical applications. Herein, we report a facile and eco-friendly one-pot strategy for the chemical reduction of graphene oxide and recombination of sulphur as the cathode material for a Li–S battery. The optimized rGO/S-3 composite material possesses a porous morphology with pore walls made of the rGO and sulphur composite. The sulphur content is about 73.5 wt%, the particle size is about 8–15 nm, and the particles are distributed evenly on the layer of rGO, wherein the thickness of rGO is about 3–4 nm, corresponding to 8–10 monolayer graphenes. The rGO/S-3 composite electrode presents a high initial discharge capacity of 1012 and 474 mA h g−1 at 1C and 10C, respectively. The discharge capacity of 451 mA h g−1 was preserved after 1200 cycles at 1C. Even though the current density increased to 10C, a discharge capacity of 237 mA h g−1 may be obtained after 400 cycles.

The development of supercapacitors with integrated high energy–power properties coupled with long cyclic life is an urgent demand in the energy storage field. The key to the assembly of such devices is to design and fabricate novel high-performance electrode materials in conjunction with matched electrolytes. In this study, a renewable graphene-like nitrogen-doped carbon nanosheet (RGNC-NS) has been constructed by using simultaneous carbonization and auto-activation followed by ultrasonic-assisted liquid exfoliation from natural layered shrimp shells. The final RGNC-NS had an optimum integration of graphene-like nanostructures (∼5 nm thick), large specific surface area (1946 m2 g−1), and rich nitrogen doping (8.75 wt%), resulting in high conductivity (7.8 S cm−1) and good surface wettability with an electrolyte. The RGNC-NS as a supercapacitor electrode exhibited an excellent rate capability with an ultrahigh capacitance of 322 F g−1 at 0.5 A g−1 and 241 F g−1 at 100 A g−1 (75% retention), as well as a long cyclic stability of 98.3% capacitance retention after 20 000 cycles at 10 A g−1 in 6 M KOH. Moreover, the RGNC-NS in a mixed ionic liquid electrolyte displayed an integrated high energy–power density of 30 W h kg−1 energy density at 64 000 W kg−1 power density and 93.2% capacitance retention after 8000 cycles at 5 A g−1.

Vinorelbine (VIN) is a semi-synthetic vinca alkaloid and is one of the most active agents for the treatment of solid tumors. The drug is commonly administered through a peripheral vein. Although VIN is known to cause local venous toxicity, such as drug-induced phlebitis, the mechanism responsible for the toxicity remains unclear. To investigate the role of Toll-like receptor 4 (TLR4) in VIN-induced vascular endothelial injury, human umbilical vein endothelial cells (HUVECs) were prepared from umbilical cords recovered with the written informed consent of the parents and treated with VIN for 60 min. Following the washing away of the VIN, the cells were cultured for a further 6 and 12 h, and the changes in TLR4 expression in the HUVECs were detected by quantitative polymerase chain reaction and western blot analyses. Finally, the effects of VIN on the translocation of nuclear factor κB (NF-κB) were determined by immunofluorescence and confocal analysis. The VIN-treated cells were stretched, extended and irregular while the control cells exhibited normal morphology. The TLR4 mRNA and protein levels were significantly higher in the VIN-treated HUVECs than those in the control group (P

Oxidative stress and inflammation are critically implicated in ambient fine particulate matter (mean diameter 2.5 μm; PM

Background CCL2 was up-regulated in neurons and involved in microglia activation and neurological decline in mice suffering from hepatic encephalopathy (HE). However, no data exist concerning the effect of neuron-derived CCL2 on microglia activation in vitro. Methods The rats were pretreated with CCL2 receptor inhibitors (INCB or C021, 1 mg/kg/day i.p.) for 3 days prior to thioacetamide (TAA) administration (300 mg/kg/day i.p.) for inducing HE model. At 8 h following the last injection (and every 4 h after), the grade of encephalopathy was assessed. Blood and whole brains were collected at coma for measuring CCL2 and Iba1 expression. In vitro, primary neurons were stimulated with TNF-α, and then the medium were collected for addition to microglia cultures with or without INCB or C021 pretreatment. The effect of the medium on microglia proliferation and activation was evaluated after 24 h. Results CCL2 expression and microglia activation were elevated in the cerebral cortex of rats received TAA alone. CCL2 receptors inhibition improved neurological score and reduced cortical microglia activation. In vitro, TNF-α treatment induced CCL2 release by neurons. Medium from TNF-α stimulated neurons caused microglia proliferation and M1 markers expression, including iNOS, COX2, IL-6 and IL-1β, which could be suppressed by INCB or C021 pretreatment. The medium could also facilitate p65 nuclear translocation and IκBα phosphorylation, and NF-κB inhibition reduced the increased IL-6 and IL-1β expression induced by the medium. Conclusion Neuron-derived CCL2 contributed to microglia activation and neurological decline in HE. Blocking CCL2 or inhibiting microglia excessive activation may be potential strategies for HE.

Effective fault diagnosis method has long been a hot topic in the field of prognosis and health management of rotary machinery. This paper investigates an effective deep learning method known as sparse filtering, which is used to extract features from fault signal directly. And then, the supervised learning method softmax regression is applied to classify the fault types. The training samples are the vibration signals under a certain rotational speed and the test samples are in different rotational speeds. The key parameters of the model are optimized and analyzed through orthogonal experiments and single factor experiment. The diagnosis results show that the sparse filtering model has strong robustness for rotating machinery fault diagnosis in the case of rotating speed fluctuations.

A novel kind of Pt/N-rGO hybrid possessing of low content 5.31 wt.% Pt anchored on the surface of nitrogen doped reduced graphene oxide (N-rGO) evenly was prepared. The Pt has uniformed 2.8 nm diameter and exposed (111) crystal planes; meanwhile, the N works as the bridge between Pt and rGO with the Pt-N and N-C chemical bonds in Pt/N-rGO. The Pt/N-rGO material has a very high electrocatalytic activity in oxygen reduction reaction with the mass catalytic activity more than 1.5 times of the commercial Pt/C due to the synergistic catalytic effect of both N-doped carbon matrix and Pt nanoparticles. Moreover, the Pt/N-rGO exhibits an excellent stability with hardly loss (only 0.4%) after accelerated durability tests of 5000 cycles based on the stable Pt-N-C chemical bonds in Pt/N-rGO, which can prevent the detachment, dissolution, migration and aggregation of Pt nanoparticles on the matrix during the long-term cycling.

In order to solve the problem of weak discernibility relation between the demands of knowledge in the process of product design, a knowledge organisation model based on granularity principle is put forward. The paper applies knowledge unit and knowledge point to describe product design knowledge, adopts granularity principle to perform the granulation tissue of product design knowledge, monitors the classification, association and inference of knowledge points according to task requirements, structures and formalises the related knowledge, and ultimately provides knowledge service in the form of knowledge unit. Through the analysis of a case, the method is proven to be effective to improve the relevance of knowledge and to improve the efficiency of knowledge service.

Dimethyl carbonate (DMC) has high oxygen content (53.3%) and a non-toxic preparation, which is a promising additive for diesel fuel. Exhaust gas recirculation (EGR) technology inhibits the formation of NOX. The combination of DMC with EGR is considered to be a practical means of meeting emissions regulations. In this study, a four-cylinder diesel engine was used to study the effects of DMC and EGR on engine emissions and performance. The three test fuels included a pure diesel (D100), 10% DMC and 90% diesel (DMC10), and 20% DMC and 80% diesel (DMC20). The results show that the DMC20 mixtures created a longer ignition delay, and resulted in the highest pressure and heat release rate. However, the use of DMC shortened the duration of the combustion. The brake specific fuel consumption of the DMC blends was higher than that of diesel, and the brake thermal efficiency of the DMC10 was higher than diesel at the same EGR. Through an energy balance analysis, DMC20 has a significant potential for exhaust gas energy recovery. Overall, DMC20 had the best combustion performance when it was used in combination with EGR rates of 20%−30%. When EGR = 40%, the NOX emission of DMC20 was reduced by 64.9%, and the soot emission was reduced by 80%. The nucleation mode and aggregation mode particulate matter (PM) emissions were less affected by EGR, the total PM concentration of DMC20 reduced to less than 20% of D100, and the mass concentration was reduced by approximately 70%.

Dimethyl carbonate (DMC)/diesel blended fuels are receiving increasing attention due to the advantages of DMC (oxygen content 53.3%) that improved the fuel-rich zone of diesel engines. However, the low cetane number (CN) of DMC/diesel dual-fuel at low loads resulted in a delayed combustion progress. Since the combustion phase had a significant effect on thermal efficiency, exergetic efficiency, energetic and exergetic losses; 2-ethylhexyl nitrate (EHN) was added to the mixed fuel as a CN improver, so that the combustion phase closed to that of diesel to ensure proper combustion characteristics of the DMC/diesel dual-fuel. In this study, a four-cylinder turbocharged diesel engine was used to study performance and emissions. Based on experiments, combustion characteristics including energy balance and exergy balance were focused, in which the EHN was added to the DMC/diesel mixture at different concentrations. The five test fuels included diesel (D100), and a mixture of 20% DMC with 80% diesel (DMC20). In addition, EHN was added to DMC20 at a ratio of 0.5%, 1%, and 2%. The results showed that EHN could shorten the ignition delay time of DMC and reduced maximum pressure rise rate (MPRR). The use of EHN improved brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC), under the same load, using 0.5% and 2% EHN, BTE increased by 0.2% and 1%, relative to DMC20, respectively. The study found that the energy efficiency and exergy efficiency were higher after adding EHN, which made up for the burning problem of DMC. Moreover, the irreversible loss reduced, and the available work and available energy increased. Thermodynamic analysis showed that DMC had better combustion performance than diesel after adding 2% EHN. In this study, the method of EHN/DMC/diesel blended fuel combining with 25% EGR was proposed and confirmed that the trade-off relationships of NOX and soot have been improved noteworthy.

Zhan, Y.; Aarninkhof, S.G.J.; Wang, Z.; Qian, W., and Zhou, Y., 2020. Daily topographic change patterns of tidal flats in response to anthropogenic activities: Analysis through coastal vid...

Supercritical carbon dioxide Brayton cycle is considered one of the most promising systems for waste heat recovery of engines because of its compactness and high energy efficiency. To further improve the fuel utilization ratio and solve the difficulties of waste heat recovery of high temperature exhaust gas, a regenerative supercritical carbon dioxide Brayton cycle/organic Rankine cycle dual loop is proposed for cascade utilization of exhaust heat from a dual-fuel engine. The regenerative supercritical carbon dioxide Brayton cycle of the proposed system is powered by the waste heat contained in the exhaust gas. The working fluid in the organic Rankine cycle is pre-heated by CO2 exiting the regenerator and then further heated by the residual heat of the exhaust gas. The flow rates of the working fluids in both sub cycles are adjusted to match the waste heat recovery system to respond to the changing conditions of the dual-fuel engine. The results revealed that the maximum net power output of this system is up to 40.88 kW, thus improving the dual-fuel engine power output by 6.78%. Therefore, such a regenerative supercritical carbon dioxide Brayton cycle/organic Rankine cycle dual loop system design enables the thorough recovery of high temperature exhaust heat, leading to higher energy efficiency and lower fuel consumption of the engine.

A novel one-step hydrothermal and calcination strategy was developed to synthesize the unique 1D oriented Co3O4 crystal nanofibers with (220) facets on the carbon matrix derived from the natural, abundant and low cost wool fibers acting as both carbon precursor and template reagent. The resultant W2@Co3O4 nanocomposite exhibited very high specific capacity and favorable high-rate capability when used as anode material of lithium ion battery. The high reversible Li+ ion storage capacity of 986 mAh g−1 was obtained at 100 mA g−1 after 150 cycles, higher than the theoretical capacity of Co3O4 (890 mAh g−1). Even at the higher current density of 1 A g−1, the electrode could still deliver a remarkable discharge capacity of 720 mAh g−1 over 150 cycles.

Tumor necrosis factor alpha-induced protein 8-like 2 (TNFAIP8L2) is a new member of the tumor necrosis factor-a-induced protein 8 (TNFAIP8) family that functions as an important factor in the maintenance of immune homeostasis. In this study, we cloned the cDNA sequences and analyzed the genomic structure of porcine TNFAIP8L2. RH mapping using the IMpRH panel showed that this gene was closely linked to microsatellite marker SW512 in pig chromosome 4. Subcellular localization analysis showed GFP-TNFAIP8L2 fusion protein distrib- uted in nucleus as well as cytoplasm including mitochon- dria and endoplasmic reticulum. Real-time PCR analysis revealed that porcine TNFAIP8L2 was more highly expressed in spleen than other tissues. To understand its characterization of transcriptional regulation, we cloned approximately 2 kb of 5 0 -regulatory region upstream to the porcine TNFAIP8L2 translational start site and generated sequential deletion constructs evaluated in dual-luciferase reporter assay. The results demonstrated that its core pro- moter is 435 base pairs (bp) upstream to the transcription initiation site. Then, site-directed mutation experiment combined with electrophoretic mobility shift assay (EMSA) indicated that M-CAT binding factor (MCBF) and activator protein 1 (AP-1) were important transcription factors for porcine TNFAIP8L2. These findings provide an important basis for further understanding of porcine TNFAIP8L2 regulation and function in swine.

Intelligent fault diagnosis methods are promising in dealing with mechanical big data owing to their efficiency in extracting representative features. However, there is always an undesirable shift variant property embedded in raw vibration signals, which hinders the direct use of raw signals in fault diagnosis networks. A convolutional neural network (CNN) is a widely used and efficient method to extract features in various fields for its excellent sparse connectivity, equivalent representation and weight sharing properties. However, raw CNN is time-consuming and has a marginal problem. Heuristically, we construct a fault diagnosis framework called adaptive overlapping CNN (AOCNN) to deal with one dimension (1D) raw vibration signals directly. The shift variant problem is dealt with by the adaptive convolutional layer and the root-mean-square (RMS) pooling layer, and the marginal problem embedded in the CNN is relieved by employing the overlapping layer. Meanwhile, the AOCNN is also characterized by adopting different convolutional strides and diverse activation functions in feature extraction network training and usage. Furthermore, sparse filtering is embedded into the AOCNN, and experiments on a bearing dataset and a gearbox dataset are conducted to verify the validity of the proposed method separately. When compared with other state-of-the-art methods this method reveals its superiority.

Started from electronic information service connotation, this paper advances the new concept of the electronic information service based on quantization of user experience. Then, the user experience was classified into four levels. Furthermore, combining the three dimensions with the four experience levels, it built a user experience quantitative index system of electronic information services, and ultimately set up a user experience quantitative concept model of electronic information services. It can provide necessary theoretical basis and practical guidance for further empirical research.

Considering the effect of the transmitting data, this paper analyzes the performance of circular SA with 8 array elements (AE) in different application scenarios. Double code- channels pointing to the same direction is the basic mode of TDD- CDMA when transmitting voice signals. However, our research has discovered that the system working in that mode is unstable. If more code-channels pointing to different direction are used, then, according to the combination of the transmitting data, the direction for the major beam-lobe will change greatly, which is hard to forecast. Moreover, when the working code-channels rise to 8 ones, the directional diagram of the beam will be similar with that of an un-directional antenna. Anyway, when using circular SA with 8 AE in TDD-CDMA system, it will be difficult to ensure the stability of directional transmission.