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As the voltage driver of megavolt power supply in Dynamitron accelerator, RF oscillator largely determines the whole system performance. A solid-state RF oscillator scheme with four elements resonant network in CLLC configuration was proposed in this article. By analyzing the operation principle of this CLLC resonant topology, three operation modes and the optimization target of resonant network parameters were discussed. The equivalent circuit model of resonant tank was built with taking the transformer parameter into account. In order to achieve optimal design, the impacts of resonant parameters on the system performance were investigated. The results indicate that larger secondary capacitance can improve system performance but may bring undesirable harmonic issue. Increasing inductance ratio of transformer would bring higher voltage output while lowering the power capability. Then, a parameter optimization method is proposed to achieve a high output voltage, while keeping the power loss and resonant current low. The feasible zone under given set of resonant parameters was determined. Finally, a prototype of RF oscillator applied in Dynamitron accelerator was developed, with a voltage of ∼79 kV and a frequency of ∼100 kHz. The influences of resonant parameters on the system performance were also verified through experiments.

Hydrogen, as an emerging energy source, is extensively utilized in industrial production. Owing to its high reactivity, hydrogen presents an explosion risk during its utilization, storage, and production, potentially resulting in significant harm to personnel and equipment. To elucidate the dynamic characteristics of external explosions induced by different ignition positions in hydrogen-related plants, this study developed a 45 m3hydrogen explosion-venting model using computational fluid dynamics technology. A fascinating numerical analysis was conducted on the flow field, distribution characteristics, and disaster evolution of external explosions induced by inner hydrogen explosions. The results show that when the ignition was far away from the vent, the combustion rate and speed of the outdoor jet flame significantly increased, thus comprehensively enhancing the trigger energy of the external explosion. A new overpressure peak structure formed by the superposition of the rupture wave and the external explosion wave was observed. Compared with the central ignition, the new shock wave intensity caused by back ignition was the highest, which could increase the overpressure level by 57% and lead to new overpressure hazards in the far field. In the case of back ignition, the high-temperature area was twice the length of the room, while the high-temperature area was the smallest when the front ignition. The ignition location did not significantly affect the position of the maximum wind velocity. However, back ignition could result in wind velocities of up to 18 times that of a hurricane wind. The research results are expected to provide a reference for explosion risk control, explosion-venting hazard mitigation, and prevention of simple industrial plants.

The compact design of the cast resin high-frequency transformers (HFTs) allows the insulation of fine structures withstand severe high-frequency square pulse voltage stress and thermal stress. The partial discharge (PD) behaviors in the presence of thermal-induced defects are investigated. The phase-resolved PD (PRPD) pattern showed that the majority of PDs occurs on the rising and falling edges of the square pulse voltage. The PD inception voltage (PDIV), PD magnitude, and PD repetition rate increase with frequency at very low frequency and decrease with frequency at high frequency. Long charge injection time at very low frequency and the heat effect at high frequency cause the diminution of these PD parameters. The PD and breakdown characteristics are examined under progressive temperature conditions, indicating an early PD degradation and electrical failure phenomenon below the glass transition temperature ( ${T}_{g}$ ). Microscopic observation revealed the formation of delamination gap defects due to the inconsistency of thermal expansion between the cast insulation and metal, which considered the cause of PDs. The decohesion model is employed to describe the structural evolution and the formation of delamination gap with varying temperatures. The model demonstrates an early damage mechanism for interfacial cohesion condition at medium temperatures and temperatures close to ${T}_{g}$ . Additional experiment enables the inference that the release of local interfacial stress under progressive temperature may lead to the formation of damaged interfaces or microcracks, which can trigger occasional PD or instantaneous filamentary breakdown.

The performance of existing sign language recognition approaches is typically limited by the scale of training data. To address this issue, we propose a mutual enhancement network (MEN) for joint sign language recognition and education. First, a sign language recognition system built upon a spatial–temporal network is proposed to recognize the semantic category of a given sign language video. Besides, a sign language education system is developed to detect the failure modes of learners and further guide them to sign correctly. Our theoretical contribution lies in formulating the above two systems as an estimation–maximization (EM) framework, which can progressively boost each other. The recognition system could become more robust and accurate with more training data collected by the education system, while the education system could guide the learners to sign more precisely, benefiting from the hand shape analysis module of the recognition system. Experimental results on three large-scale sign language recognition datasets validate the superiority of the proposed framework.

To assess post‐COVID‐19 vaccination gout flare risk with differing baseline flare burden. We prospectively studied gout patients with infrequent or frequent flares, defined as ≤1 flare/year or ≥2 flares/year, respectively. COVID‐19 vaccine‐naive patients managed with urate‐lowering therapy between February and June 2021 were included and voluntarily decided on vaccination. Participants were followed for 12 weeks after enrollment or first vaccine dose. Gout flares and risk factors were compared between groups. Of 530 participants, 308 (58.1%) had infrequent flares and 222 (41.9%) had frequent flares at baseline, with 248 (142 infrequent and 106 frequent) receiving two‐dose COVID‐19 vaccination. Vaccination increased cumulative flare incidence at 12 weeks in the infrequent but not the frequent flare group (26.1% vs 10.8%, P= 0.001, compared with 60.4% vs 65.5%, P= 0.428). Flare incidence in the final 4 weeks of observation decreased significantly only in the vaccinated infrequent flare group (4.3% vs 12.0%, P= 0.017). Multivariable analyses showed that vaccination (odds ratio [OR] 2.82, 95% confidence interval [95% CI] 1.50–5.30, P= 0.001), flare in the preceding year (OR 1.95, 95% CI 1.03–3.71, P= 0.04), and body mass index (OR 1.09, 95% CI 1.01–1.19, P= 0.03) were independently associated with increased flare risk in the infrequent flare group. Baseline serum urate (mg/dl) was an independent risk factor in the frequent flare group (OR 1.23, 95% CI 1.05–1.45, P= 0.012). COVID‐19 vaccination was associated with increased early gout flares only in patients with previously infrequent flares.

Pd/SSZ-13 has been proposed as a passive NOxadsorber (PNA) for low-temperature NOxadsorption. However, it remains challenging for Pd/SSZ-13 to work efficiently when suffering from phosphorus poisoning. Herein, we report a simple and efficient strategy to regenerate the phosphorus-poisoned Pd/SSZ-13 based on the cooperation between hydrothermal aging treatment and Na cocations. It was found that hydrothermal aging treatment enabled the redispersion of Pd and P-containing species in phosphorus-poisoned Pd/SSZ-13. Meanwhile, the presence of Na cocations significantly reduced the formation of AlPO4and retained more paired Al sites for highly dispersed Pd2+ions, which was of great importance for the recovery of adsorption performance. To our satisfaction, the restoration ratio of the adsorption capacity of poisoned Pd/SSZ-13 was >90% after regeneration. Strikingly, the NOxadsorption activities of phosphorus-poisoned Pd/SSZ-13 with phosphorus loadings of 0.2 and 0.4 mmol g–1almost completely recovered upon regeneration. This study demonstrates the promoting effect of Na cocations on the regeneration of phosphorus-poisoned Pd/SSZ-13 by hydrothermal aging treatment, which provides useful guidance for the design of PNA materials with excellent durability for cold-start application.

Due to the selective attenuation of light in water, captured underwater images exhibit poor visibility and cause considerable challenges for vision tasks. The structural and statistical properties of different regions of degraded underwater images are damaged at different levels, resulting in a global nonuniform drift of the feature representation, causing further degradation of visual performance. To handle these issues, we present an underwater image enhancement method via multi-interval subhistogram perspective equalization to address the issues posed by underwater images. We estimate the degree of feature drifts in each area of an image by extracting the statistical characteristics of the image, using this information to guide feature enhancement to achieve adaptive feature enhancement, thereby improving the visual effect of degraded images. We first design a variational model that uses the difference between data items and regular items to improve the color correction performance of the method based on subinterval linear transformation. In addition, a multithreshold selection method, which adaptively selects a threshold array for interval division, is developed. Ultimately, a multi-interval subhistogram equalization method, which performs histogram equalization in each subhistogram to improve the image contrast, is presented. Experiments on underwater images with various scenarios demonstrate that our method significantly outperforms many state-of-the-art methods qualitatively and quantitatively.

In this study, a series of polypropylene-g-maleic anhydride-g-CnH2n+1OH (PMCn, n = 18, 22, 26) comb-like polymeric phase change materials (CPCMs) are fabricated through the solvent-free esterification reaction between polypropylene-g-maleic anhydride(PP-g-MAH)and n-alkyl alcohol with side-chain lengths varying from n = 18, 22 to 26. The pendant side alkyl groups along PP-g-MAH exhibit obvious side-chain crystallization behavior, and phase transition temperature and heat enthalpy of PMCnincrease from 60.0 to 82.2 °C and from 53.6 to 118.4 J/g with increasing the side-chain length, respectively. PMCnseries CPCMs demonstrate excellent shape stabilization and thermal performance owing to the protection and anchoring role of the PP backbone, and the form-stabilized temperature at 135 °C and 300-time thermal cycles further verify their excellent structural stability and reliability. PMC18 shows a longer thermal buffering time of 362 s and the maximum ΔT at 11.3 °C, and the coated fabric by PMC18 gives a 110 s thermal buffering time during the heat storage process, proving its outstanding thermoregulated ability. The presented PMCnseries CPCMs with excellent structural-stabilized performance demonstrate a prospective thermal management application.

Graphical Abstract:

Cu-SAPO-34 catalysts used for the selective catalytic reduction with ammonia (NH3-SCR) reaction deteriorate when exposed to moisture at low temperature (<100 °C), which seriously hinders their commercial application prospects. In this work, Cu-SAPO-34 catalysts templated using various structure-directing agents (SDAs), i.e., DEA, TEA, PA, and TEAOH, were elegantly fabricated viaa “one-pot” protocol. The direct relationship between the various SDAs and low-temperature moisture degradation were determined in this work. Viathorough characterizations, it was evidenced that the Cu-SAPO-34 catalysts with more Si–O(H)–Al bonds, more Cu(OH)+moieties and fewer CuOxclusters exhibited higher SCR catalytic activities and N2selectivity. After low-temperature hydration treatment, the relative crystallinity, porosity, Si–O(H)–Al density, and active Cu(OH)+in the catalysts declined, but in varying degrees, where the Cu-SAPO-34 catalysts possessing more Si–O(H)–Al density and Cu(OH)+moieties being the more susceptible to hydrolysis and structural degradation, and vice versa. In situdiffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis confirmed that both the fresh and degraded Cu-SAPO-34 catalysts primarily follow the Langmuir–Hinshelwood pathway due to its faster reaction rate and lower reaction barrier than the Eley–Rideal pathway.

A green and efficient way of synthesizing Cu-SAPO-18 was developed, which is characterized by the one-pot method and recycling of the mother liquid. All fresh samples synthesized with or without the mother liquid exhibit similar structural properties, Si/(P + Al), and particle sizes. However, all fresh catalysts show some differences in Brunauer–Emmett–Teller surface areas, Cu content, roughness of the crystal surface, and Si coordination. Temperature-programed desorption of ammonia, 29Si magic angle spinning nuclear magnetic resonance, temperature-programmed reduction experiments by H2, electron paramagnetic resonance, and UV–vis-diffuse reflectance spectroscopy results suggest that the mother liquid declines the content of acid sites, Cu2+and CuO of Cu-18-0.5 and Cu-18-1. Therefore, Cu-18-0.5 and Cu-18-1 exhibit a decline in low-temperature activity but an increase in high-temperature activity, compared to Cu-18-0. During aging treatment, the mother liquid contributes to the movement of CuO to ion-exchange sites and new isolated Cu2+ions are generated. However, excess mother liquid causes severe structural damage of Cu-18-1. Finally, Cu-18-0.5 exhibits the best hydrothermal stability owing to the more active Cu2+sites and less structural collapse.

The cold start wetting effect on Cu-SSZ-13 has been simulated via soaking catalysts with various Si/Al ratios in ammonium water at disparate pH levels. It is found that a mild treatment (pH = 9) has little effect on the selective catalytic reduction of NOxwith NH3performance of Cu-SSZ-13. However, on increasing the pH to 12, the deNOxactivity and resistant ability to hydrothermal aging decrease obviously. Such a decrease could be attributed to the desilication phenomenon during the soaking process, which results in a number of effects including extraction of Cu2+ions from the exchange sites, decrease in acidity, and damage to the zeolite structure. Meanwhile, the alkaline treatment exhibits distinct impacts on the physicochemical properties of Cu-SSZ-13 with different Si/Al ratios. The low Si/Al ratio catalyst (Si/Al-6) is insusceptible to desilication because of a higher content of the AlO4–structure and extra-framework Al (Alef), which could hamper the desilication.

This article proposes a robust visual following approach with a deep learning-based person detector, a Kalman filter (KF), and a reidentification module. The KF is introduced to predict the position of the target person, and its state is updated by the associated detection result. To deal with severe distractions and even full occlusion, the reidentification module with an identification model, a verification model, and an appearance gallery is employed in multi-person disturbing environments. Without any customized markers, the proposed approach can follow the target person steadily, and it is robust to occlusion and posture changes of the target person. Experiments results validate the effectiveness of the proposed approach.

A risk assessment method of dust explosion applicable to wood product processing enterprises was studied to effectively control the occurrence of dust explosion accidents. First, considering the explosive attributes of dust and the technical attributes of wood product processing, a risk assessment index system for dust explosion was constructed from the human, machine, environment, and management perspectives. It comprises 3 first-level indices (namely: accident possibility, accident severity, and safety management system), 6 second-level indices, and 28 third-level indices. The weight of each index was calculated using the structural entropy weight method (SEWM). Second, combined with an association degree matrix, a theoretical model for dust explosion risk assessment was established using a three-dimensional matrix method. Finally, an empirical analysis was conducted on a wood product processing plant using the established model. It was concluded that the overall risk level of the plant was level IV, indicating a relatively high risk. This conclusion is consistent with the actual operation status of the plant, showing that the model has a certain degree of applicability and effectiveness.

Despite the growing awareness on the importance of gut microbiomes, understanding marine mammal gut microbiomes remains limited due to difficulties in sampling. Spotted dolphins (Stenella attenuata) are widely spread oceanic cetaceans, and there is a gap in knowledge regarding their gut microbiology. In this study, we opportunistically collected samples from both wild and human-cared spotted dolphins in the southern waters of Hainan Island, China. This provided the opportunity to examine the composition and diversity of the gut microbial communities of this cetacean species. Since these dolphins inhabit a similar water environment, different food sources might be the primary factor distinguishing the gut microbiomes of wild and human-cared populations, offering valuable experimental material to investigate potential differences in gut microbial community structure among marine mammals in similar environments but with varying food sources. We found that the gastrointestinal microbial community structure of wild and human-cared dolphins demonstrated significant differences, both overall and at specific locations. However, no significant difference was observed in the microbial diversity of their gastrointestinal tracts, indicating that the disparities primarily lie in microbiota composition. Additionally, we detected numerous potentially pathogenic bacteria, suggesting a comprehensive future study of marine mammal gut microbiology. Such a study might involve determining health indicator factors associated with these microbiomes. Our study not only supplements information on the gut microbiology of spotted dolphins but also delves into the similarities and differences in gastrointestinal microbial communities within the same marine mammal species when food source variations play a significant role in their lives.

Nitrogen oxides are one of the most significant pollution sources during coal combustion. This experimental study was conducted in a 15 kWthlab-scale pressurized fluidized bed (inner diameter = 81–100 mm, H = 2100 mm) firing with bituminous coals. The effects of operating parameters, including bed temperature (800 °C–900 °C), operating pressure (0.1–0.4 MPa), excess air level (16%–30%) and flow pattern on NOxand N2O emissions were systematically studied during the tests. During each test the interaction effects of all the operating parameters were properly controlled. The results show that most operating parameters have an opposite effect on NOxand N2O emissions, and the N2O emissions mainly depend on the bed temperature. Increasing the operating pressure can significantly suppress the fuel-N conversion to NOxbut enhance its conversion to N2O. With the rise of the excess air level and fluidization number, NOxemissions grow distinctly while N2O emissions remain almost unchanged. Total nitrogen oxide emissions increase with the bed temperature while decrease with the operating pressure.

Contaminants (K, Na, Ca, and Mg) were introduced into Cu-SAPO-18 via incipient wetness impregnation to investigate their effect on the selective catalytic reduction of NOxwith NH3(NH3-SCR) over Cu-SAPO-18. After the introduction of contaminants into Cu-SAPO-18, the quantity of acidic sites and Cu2+species in catalyst decreases owing to the replacement of H+and Cu2+by K+, Na+, Ca2+, and Mg2+. Furthermore, the loss of isolated Cu2+ induces the generation of CuO and CuAl2O4-like phases, which causes further loss in the Brunauer-Emmett-Teller surface area of the catalyst. Consequently, the deNOxperformance of the contaminated Cu-SAPO-18 catalysts drops. Such decline in NH3-SCR performance becomes more pronounced by increasing the contaminant contents from 0.5 to 1.0 mmol/gcatal. In addition, the deactivation influence of the contaminants on Cu-SAPO-18 is presented in the order of K> Na > Ca > Mg, which is consistent with the order of reduction of acidic sites. To a certain degree, the effect of the acidic sites on the deactivation of Cu-SAPO-18 might be more significant than that of isolated Cu2+and the catalyst framework. Moreover, kinetic analysis of NH3-SCR was conducted, and the results indicate that there is no influence of contaminants on the NH3-SCR mechanism.

Pressurized oxy-coal combustion is considered as a promising carbon capture technology as a result of its potential of high efficiency and low cost in CO2capture. However, experimental investigations of oxy-coal combustion under pressurized conditions are far less common than those under atmospheric pressure conditions, and hence, further research is needed to elucidate the effects of pressure on oxy-coal combustion in terms of combustion performance, emissions, etc. In this study, a series of oxy-coal combustion experiments were carried out under the pressures from 0.1 to 0.4 MPa on a 15 kWthfluidized bed combustion system. The effects of the combustion pressure and oxygen concentration in the oxidant on the temperature profile, unburnt carbon, combustion efficiency, fly ash composition, and NOxemission were investigated. The experimental results have shown that the CO2concentration in the oxy-combustion flue gas under different combustion pressures have all exceeded 90%, which is beneficial to the carbon capture process. An increase in pressure is helpful to reduce the unburnt carbon in the fly ash and improve the combustion efficiency under all of the tested oxy-combustion atmospheres. The NOxemission decreases with combustion pressure within the investigated range of 0.1–0.4 MPa, while the reduction is more pronounced at lower pressures. Besides, the effect of combustion pressure on the chemical composition of the fly ash is found to be insignificant.

Nonpolar ZnO films are deposited on (100) Si substrate using LaNiO3 conducting buffer layer by radio frequency sputtering. X-ray diffraction results show that ZnO films are (110) and (002) orientation with and without LaNiO3 buffer layer. The current behavior of ZnO/LaNiO3 heterojunction exhibits ohmic conduction which is different from the diode-like rectification current behavior of ZnO film using insulated buffer layers. The photoluminescence properties indicate that the (110)-oriented nonpolar ZnO film has better band-edge emission than that of (002)-oriented polar ZnO film. It is suggested that LaNiO3 buffer layer can be used to deposit silicon-based ZnO film with well ohmic contact electrode in optoelectronic devices.

ABSTRACTBackground: ZOSTAVAX (ZVL; Zoster Virus Live), is a single dose, live, attenuated vaccine licensed for the prevention of herpes zoster (HZ) and post herpetic neuralgia (PHN) in adults ≥50 years of age. Injection site adverse events (AEs) of erythema, swelling and pain were solicited within 5 days post vaccination in the 2 pivotal studies of ZVL; ZEST (ZOSTAVAX Efficacy and Safety Trial) and SPS (Shingles Prevention Study). Protocol specified criteria were used to report the frequency and intensity of injection site AEs in ZEST and SPS studies. Subsequently, the FDA Toxicity Grading Scale provided guidance for uniform assessment of AEs across all adult vaccine clinical trials. The objective of this post-hoc analysis was to categorize the previously reported injection site AEs in two pivotal trials of ZVL according to the current FDA Toxicity Grading Scale.Methods: The current FDA Toxicity Grading Scale provides a measure for classifying injection site AEs by four grades [Grade 1 (mild); Grade 2 (moderate); Grade 3 (severe) and Grade 4 (life threatening)]. Injection site erythema, swelling, and pain intensity gradings were assigned to the respective FDA Toxicity Grade based on this appropriation. A descriptive analysis of the proportion and risk difference (within 95% confidence intervals) of injection site AEs per the FDA Toxicity Grading Scale is provided.Results: The frequency of injection site AEs (erythema, swelling, pain) after subcutaneous vaccination with ZVL were higher in recipients of ZVL compared with placebo. Majority of the injection site AEs observed were Grade 1 (mild) or Grade 2 (moderate) in intensity. Additionally, Grade 3 (severe) injection site AEs were observed infrequently.Conclusions: Application of the FDA Toxicity Grading Scale provides a uniform AE assessment tool across different adult vaccines. This post hoc summary of injection site AEs using FDA Toxicity Grading Scale provides further evidence of low frequency of severe injection site AEs post ZVL vaccination.

Recipients of autologous haemopoietic stem-cell transplants (auto-HSCT) have an increased risk of herpes zoster and herpes zoster-related complications. The aim of this study was to establish the efficacy and safety of an inactivated varicella zoster vaccine for the prevention of herpes zoster after auto-HSCT.

Hyper activity of protooncogene c-Mycis one of the hallmarks of highly aggressive lymphomas. However, the mechanism of how c-Mycis subjected to activation and amplification is still not well defined. In this study, we use gene knockout strategy to show that targeted depletion of a well-conserved microRNA gene locus miR-144/451initiates tumorigenesis including B-lymphoma development in aged mice. This is due, at least in part, to the direct activation of the c-Mycgene by loss of miR-144/451expression in hematopoietic cells. Moreover, oncoprotein c-Myc inversely regulates miR-144/451expression by directly binding to the miR-144/451promoter region, forming a miRNA-Myc positive feedback loop to safeguard the high level of c-Myc in B-lymphocytes. We also demonstrate that this miRNA-Myc crosstalk is disrupted in human diffuse large B-cell lymphomas with aberrant c-Mycexpression. Therefore, our findings provide strong evidence, for the first time, that deficiency of miR-144/451expression may play a bona fide role in derepression of silenced c-Myc, which contributes to tumor development including B-lymphomagenesis.

The evaluation of catalytic activity for Rh–Pd/YBa(Co1−xMx)4O7/γ-Al2O3(M=Al, Ce, Zr, and La) showed that the efficiency of NOxreduction depends strongly on the nature of the OSMs. Among a series of oxygen storage materials, YBa(Co1−xMx)4O7(M=Ce, Zr, La, Ga and In) studied for catalyst enhancement, only the catalyst with YBa(Co0.9Ce0.1)4O7has better conversion efficiency respectively (85% of NO, 96% of CO and 92% of HC). After treatment at 1000°C for 3h, these fresh catalysts showed a substantial decrease of their catalytic activities, only Rh–Pd/YBa(Co0.9Ce0.1)4O7/γ-Al2O3retains its high catalytic activity.

A process for the production of glycerol carbonate (GC) is proposed with the transesterification of glycerol (GL) and dimethyl carbonate (DMC) with CaO as catalyst by reactive distillation and extractive distillation. The performance of solvents in separating DMC-methanol azeotrope and the effects of operation parameters on the reactive distillation process are investigated experimentally. The results indicate that both the GL conversion and GC yield increase with the DMC/GL molar ratio, reflux ratio, final temperature of tower bottom, and CaO/GL molar ratio and decrease as the recycle number of CaO increases. The calcium concentration in the residual reaction mixture also decreases remarkably as the DMC/GL molar ratio increases. At DMC/GL molar ratio 4.0, reflux ratio 1.0, final temperature of tower bottom 358K, and CaO/GL molar ratio 0.05, both the GL conversion and GC yield can reach above 99.0%, and the mass concentration of calcium in the product is less than 0.08%.

V2O5/WO3-TiO2catalysts were prepared by conventional impregnation (VWTi-con) and ultrasound-assisted impregnation methods (VWTi-HUST). Their catalytic performance was tested for the selective catalytic reduction (SCR) of NO with NH3. The effects of the preparation methods on the catalyst properties were studied. The catalysts were characterized by X-ray diffraction, scanning electron microscopy, Raman and X-ray photoelectron spectroscopy. Both structural investigation and NH3-SCR activity showed that the preparation method had a strong effect on the thermal behavior of the V2O5/WO3-TiO2catalysts. After a hydrothermal treatment, a significant loss of NO reduction activity was observed for the VWTi-con catalyst, which suffered severe sintering and even formed a rutile VxTi1-xO2solid solution, while the VWTi-HUST catalyst had the same good hydrothermal stability as a commercial catalyst, indicating that the VWTi-HUST catalyst can be used in a commercial diesel after-treatment system. The ultrasound-assisted impregnation method produced a stronger interaction between the vanadium species and WTi support, which stabilized the vanadium species in the reduced state.

Caffeine is an important secondary metabolite of tea plants whose content is affected by multiple factors during its synthesis. In the present study, a series of experiments on different tea cultivars were performed to investigate the following factors that influence the ratio of caffeine content to theobromine content, coding single‐nucleotide polymorphisms (cSNPs), and expression levels of three key enzyme genes (TCS1, TIDH, and sAMS). The results revealed a significantly positive correlation with the caffeine and theobromine contents of different tea cultivars. There were 7, 8, and 7 cSNPs in the coding sequences of TCS1, TIDH, and sAMS, respectively. Among them, the TCS1A995C, TIDHT573A, and sAMSC393T cSNP sites were significantly associated with the caffeine content. Gene expression was detected by the quantitative real‐time polymerase chain reaction (qRT‐PCR) method, and it suggested a significant association of TCS1expression with caffeine content but not with theobromine content. TIDHand sAMSexpression levels had no significant association with either caffeine or theobromine content. Therefore, it could be concluded from the study findings that the following three factors had a significant influence on the biosynthesis of caffeine in tea plants: the precursor theobromine content; SNPs in TCS1, TIDH, and sAMSin the coding region; and TCS1expression level.

Based on the concept, composition and characteristics of virtual instrument technology and its LabVIEW software platform, this article proposes a new solution for mine hoist control system. Compared with the traditional monitoring system, this development time is shorter, execution efficiency is higher, and easier to study and grasp, etc. So it can be widely used in mine monitoring system.

Time progression models provide a significant advantage in developing clinical trials and can also be used to elicit comparisons among therapeutic agents. The authors performed a meta-analysis to construct a time progression model for rheumatoid arthritis (RA), an area of significant interest for pharmaceutical development, using the ACR20 end point. Compounds studied were chiefly monoclonal antibodies that were used in conjunction with methotrexate. The study shows that an exponential time response model adequately fits the data. From the modeling, a distribution of effects for biological RA therapies can be provided.

Time progression models provide a significant advantage in developing clinical trials and can also be used to elicit comparisons among therapeutic agents. The authors performed a meta-analysis to construct a time progression model for rheumatoid arthritis (RA), an area of significant interest for pharmaceutical development, using the ACR20 end point. Compounds studied were chiefly monoclonal antibodies that were used in conjunction with methotrexate. The study shows that an exponential time response model adequately fits the data. From the modeling, a distribution of effects for biological RA therapies can be provided.

The equipment is a focus of the military enterprise asset management as the floating assets. There are contradictions between the equipment quality supervision and the modern weapons and equipment development. This paper proposes the solution to establish the information management for equipment quality. Then discusses the projection of information management, and elaborates the system framework and the function which the information management system needs to have. Lastly, taking computer technology as a platform and equipment defect archives as a database, establishes the information management system with auxiliary decision-making function. The text truly realizes the informationization management and the intelligent judgment and pointes out the more effective methods for quality management of inventory assets.

In Oxley’s machining theory, efforts have been made to address work hardening and thermal softening effects and allow the material to flow continuously through an opened-up deformation zone. However, the strain, strain rate and temperature were calculated based on the average values. The distributions of these processing parameters, which are essential to describe the continuous flow, were not taken into account. In particular, the hodograph was adopted from the single shear plane model, in which the velocity field allowing for the continuous deformation was not described, and the issue of velocity discontinuity has not been resolved. In the current work, based on the detailed analysis on the boundary conditions of the velocity and shear strain rate fields, the thick ‘equidistant parallel-sided’ shear zone model was revisited. A more realistic nonlinear shear strain rate distribution has been proposed under the frame of non-equidistant primary shear zone configuration, so that all the boundary conditions can be satisfied. The obtained results have been compared with those obtained using the original Oxley analysis and the experimentally measured values. Although there was no significant difference in the force prediction, a clear improvement in the prediction of the deformation zone thickness was obtained.

Dissipative particle dynamics (DPD) is used in this work to simulate the distribution of carmustine (BCNU) molecules in konjac glucomannan (KGM) as potential drug carrier. It is shown from DPD simulation that the aggregated morphology of KGM differs at varying BCNU concentration levels. At 1 mol % of BCNU the phase aggregates as spherical particles, and at 5 mol% of BCNU, some BCNU molecules were partially uncovered by KGM molecules due to high drug concentration. However, even at higher concentration, most of the BCNU molecules are distributed in the inner area of the matrix, indicating that KGM interacts with BCNU well and it is a promising drug carrier for BCNU in water. DPD simulations may provide a powerful tool for designing drug delivery systems.

Methane-air explosion is one of the main accidents in coal mines. In this paper, the hazard effects of the gas explosion in a long straight coal laneway were studied by virtue of numerical simulation. Distribution characteristics of the shock wave overpressure, the flame speed and the temperature field were obtained. Along the increasing axial distance, shock wave overpressure increases in original methane-air area and decreases beyond the original methane-air area. Range of flame exceeds original methane-air area. Flame accelerates continually in original methane-air area and decelerates beyond the original methane-air area. The temperature attenuates slowly along the increasing distance in the flame area by virtue of flame front, and attenuates quickly along the increasing distance beyond the flame region. High temperature hazard involves farther area beyond original methane-air area.

Due to the technology limitation and inferior deNOxefficiency of urea selective catalytic reduction (SCR) catalysts at low temperatures, passive NOxadsorber (PNA) for decrease of NOx, CO and hydrocarbons (HCs) during “cold start” of vehicles was proposed to meet the further tighten NOxemission regulations in future. Among them, Pd modified zeolite PNA materials have received more attention because of their excellent NOxstorage capacity, anti-poisoning and hydrothermal stability and since Pd/zeolite PNA was proposed, a variety of advanced characterization methods have been applied to investigate its adsorption behavior and structure-performance relationship. The comprehension of the active sites and adsorption chemistry of Pd/zeolite PNA was also significantly improved. However, there are few reviews that systematically summarize the recent progress and application challenges in atomic-level understanding of this material. In this review, we summarized the latest research progress of Pd/zeolite PNA, including active adsorption sites, adsorption mechanism, material physicochemical properties, preparation methods, storage and release performance and structure-performance relationships. In addition, the deactivation challenges faced by Pd/zeolite PNA in practical applications, such as chemical poisoning, high temperature hydrothermal aging deactivation, etc., were also discussed at the micro-level, and some possible effective countermeasures are given. Besides, some possible improvements and research hotspots were put forward, which could be helpful for designing and constructing more efficient PNA materials for meeting the ultra-low NOxemission regulation in the future.