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Fabrication of a dense polymer/ceramic composite membrane with high permeability remains a great challenge. In this study, a highly selective polydopamine (PDA)/ceramic composite nanofiltration (NF) membrane was prepared by using an Al

The mutation landscapes and clinical significance of clonal hematopoiesis (CH) in idiopathic cytopenia of undetermined significance (ICUS) is still unclear. Based on the next-generation sequencingdata of 281 ICUS patients, we sought to depict the profile of CH in ICUS and evaluate its role in disease progression. It was found that CH occurred in 27% of the patients, and was more prevalent in male patients. The incidence of CH accumulated with age. AXSL1, DNMT3A, U2AF1 and TET2 were the most frequently mutated genes. Exclusive mutations existed in DNMT3A and U2AF1, and co-occurring mutations were found between SRSF2 and TET2, SRSF2 and WT1. Fifteen of the 281 ICUS patients transformed to hematological malignancies, and CH group had a higher incidence of leukemic transformation than non-CH group. Variant allele frequencies (VAFs) of the mutated genes, such asASXL1, U2AF1 and TP53, showed an obvious elevation after disease transformation. Moreover, CH patients had a shorter overall survival and progression-free survival. These data indicated that CH was a common phenomenon in ICUS patients, and it contributed greatly to the increased risk of disease progression, suggesting the significance of gene mutation monitoring in ICUS management.

Extreme vibration often occurs on TBM main system during the tunneling process. This paper established the mathematical model for TBM main system considering the impact load, time-varying internal incentive and the complex coupling relationship between each vibration degree of freedom. The dynamic model was modified by the multi-point vibration measured data. The calculation error of the system response of the main support frame’s main vibration direction was within 10%. And it was found that the overturning vibration and axial vibration of the system were the main forms of vibration of the system. It was determined that the low-frequency vibration of 15–20 Hz was a coupled vibration of system’s first to fourth mode vibration mode. Based on the vibration characteristics of TBM main system, this paper designed a tuned mass vibration absorption structure (TMVAS) that can adapt to the multi degree of freedom (MDOF) coupling vibration of TBM main system during the actual tunneling process. To minimize system vibration, the optimal design parameters of the system was determined. The maximum amplitude of the axial and horizontal overturning vibration of the support frame was reduced by 26.7 % and 13 %, and the maximum amplitude of the cutterhead’s axial vibration was reduced by 23.2 %.

A novel electrostimulated ZVI-assisting functional ceramic filter -UBF/ceramic membrane MBR was evaluated for possessing low COD/(sulfate plus organic sulfur) high-strength para-ester wastewater in terms of COD, NH4+-N abatement and para-ester degradation. The porous functional ceramic filter was prepared as new biofilm material in the novel UBF. The 200 days' successive operation indicated that the combined UBF system is an on-site upgrading anaerobic technology for methanogenesis, gaving a satisfied performance even at a COD/(sulfate plus organic sulfur) ratio as low as 1.57 with OLR up to 6.8 g COD/L/day. Bacteroidetes, Chloroflexi, Firmicutes and Proteobacteria phyla were prevalent on day 200. The appearance of the Mesotoga genus can in charge of the para-ester degradation. Desulfovibrio with a relative abundance of 2.68% was the dominant sulfate-reducing bacterium (SRB) followed by Desulfarculus. The ceramic membrane MBR was then fed with the UBF effluent at a COD/(sulfate plus organic sulfur) of 1.57 at the optimal OLR. After 75 days of operation, the final effluent quality with a COD, para-ester, and NH4+-N of 171 mg/L, 22 mg/L and 27 mg/L, respectively, was discharged up the standard required. The result suggested the potential applicability of the integrated system in treating para-ester wastewater.

Over the last 30 years, the successful implementation of the anammox process has attracted research interest from all over the world. Various reactor configurations were investigated for the anammox process. However, the construction of the anammox process is a delicate topic in regards to the high sensitivity of the biological reaction. To better understand the effects of configurations on the anammox performance, process-kinetic models and activity kinetic models were critically overviewed, respectively. A significant difference in the denitrification capabilities was observed even with similar dominated functional species of anammox with different configurations. Although the kinetic analysis gained insight into the feasibility of both batch and continuous processes, most models were often applied to match the kinetic data in an unsuitable manner. The validity assessment illustrated that the Grau second-order model and Stover–Kincannon model were the most appropriate and shareable reactor-kinetic models for different anammox configurations. This review plays an important role in the anammox process performance assessment and augmentation of the process control.

Polycyclic aromatic hydrocarbons (PAHs) are a persistent and prevalent class of pollutants in petroleum-contaminated saline environment, which pose potential harm to organisms. Researches on anaerobic biodegradation of PAHs are gradually emerging, but the response of anaerobic microorganisms to salinity changes and the co-effects of salinity and PAHs in anaerobic digestion (AD) system have seldom been reported. Thus, we investigated the variations of AD system performance and anaerobic microbial community caused by different concentrations of naphthalene (Nap) or/and NaCl based on Box-Behnken Design (0 mg/L ≤ Nap ≤150 mg/L, 0 g/L ≤ NaCl ≤25 g/L). The promoted efficiencies of acidogenesis and methanogenesis were found in presence of moderate NaCl or Nap, but high salinity (NaCl >4.4 g/L) weakened AD performance. Moreover, the high salinity (NaCl >4.4 g/L) and Nap resulted in reduced microbial Ca2+ Mg2+- ATPase activity, poor EPS secretion and the highest difference of the microbial operational taxonomic units (OTUs), and synergistically inhibited AD process. Microbiological analysis revealed that the relative abundance of Clostridium and acetoclastic Methanosaeta was increased by 2.01 times and 2.17 times in single Nap treated group compared to control. With the simultaneous addition of NaCl and Nap, Proteiniphilum and hydrogenotrophic methanogens (Methanobacterium, Methanofollis, and Methanolinea) occupied the major abundance. Potential functions prediction indicated that high salinity could disrupt the co-metabolism between carbohydrate metabolism and Nap degradation. This study provides basis for anaerobic bioremediation of PAHs-polluted saline environment.

As the main bearing components of vehicle wheel/rail systems, railway bearings take on the main load of wheel/rail system. These bearings can be easily damaged after a long-term load, which causes vibrations and significant deterioration of force distribution and directly affects the driving stability of the locomotive. Current systems available for modeling the dynamics of wheel/rail systems rarely consider nonlinear contact load bearing, which causes errors in the calculation of wheel/rail system dynamics. According to the bearing structure characteristics and working features of a specific system, this paper thoroughly evaluates the flexible deformation of shaft and bearing, time-varying nonlinear contact load, track irregularity, and bearing to establish a wheel/rail system coupling dynamics model. Then, based on the coupling dynamics theoretical model, the wheel/rail system’s coupling nonlinear dynamic characteristics are studied under random load. Then, this theoretical model of the wheel–bearing–rail system dynamics is verified using the railway bearing as an example. Finally, the model is applied to the process of rail/wheel low force design. Results show that under irregular stimulation, the maximum contact load increased by 71.2% and the maximum contact stress increased by 19.6%. After moderate wear, the wheel/rail system vibration and loading condition deteriorate rapidly. Under the low rail/wheel force, the wheel tread and diameter had significant effects on wheel/rail contact force distribution. The rail specifications are found to affect the wheel/rail system’s vibration significantly. This paper has important theoretical value and practical significance for developing reliable railway bearings and wheel/rail systems with good static/dynamic characteristics that can withstand dynamic impact load. Refereed/Peer-reviewed

Tunnel boring machine (TBM) is seriously damaged due to excessive vibration, and its anti-vibration design is the key of the drive system design. At present, the coupling model between the gear load imbalance and the electronic control strategy is difficult to be established. The actual cutterhead vibration and the motor output torque law are unknown, which make the TBM system dynamical model different from the actual situation. The calculation accuracy is difficult to estimate. In this paper, the electromechanical coupling model of TBM’s main drive system is established. The real-time dynamic load of each pinion is taken as the input disturbance of the electrical system, and the real-time output torque of each motor calculated by electrical system is inputted as the dynamic model load. Compared with the measured data, the error of the maximum amplitude of the radial acceleration is less than 20% and the dynamic torque amplitude is 9.55%. At the same time, the results show that with the rotation of the cutterhead, the loads between the motors, the output torque, and the gear radial vibration are periodically changed. When the motor load difference is maximum, the motor output torque difference is 49% of the average output torque, and the maximum amplitude of large ring gear and pinion radial vibration amplitude is 1.5–2 times the average. Refereed/Peer-reviewed

The main drive system is the core of a Tunnel Boring Machine (TBM). The force transmission law of this system is extremely complicated, which leads to severe vibration, structural failure, and safety hazards. Therefore, the dynamic analysis and the study of the vibration transmission law of a TBM main system under different working conditions are very important. In this study, a novel testbed for a hard rock TBM main system and a multi-DOF coupling dynamics model were built by considering the external excitations of the cutters, the time-varying meshing stiffness of the gear teeth, the meshing error, the clearance, and the stiffness of the main bearing. A wireless vibration monitoring system was built on the testbed. Experiments under typical working conditions were done to verify the dynamic model. Finally, the dynamic response of the system was analyzed. The results showed that the maximum error of the theoretical and actual dynamic response was 18.1%, and the dynamic model could be used to analyze the vibration of an actual TBM. The vibration law of the testbed was close to the actual TBM, so the testbed could be used for the vibration law analysis of the actual TBM under other working conditions. The study of the vibration law under different working conditions and different digging parameters could be used to guide the intelligent tunneling of the TBM.

Environmental problems, such as climate change, pollution, and environmental degradation, are important contributors to the spread of infectious diseases, such as COVID-19 and SARS. For instance, a greater concentration of ambient NO2 was associated with faster transmission of the SARS-CoV-2 virus, which causes COVID-19. However, it remains unclear whether outbreaks of infectious diseases arouse individuals’ concern on the need to protect the environment and therefore promote more pro-environmental behaviors. To this end, we examined the relationship between infectious disease vulnerability and pro-environmental behaviors using data from a cross-societal survey (N = 53 societies) and an experiment (N = 214 individuals). At both the societal and the individual levels, infectious disease vulnerability increased pro-environmental behaviors. At the societal level, this relationship was mediated by citizens’ level of environmental concern. At the individual level, the relationship was mediated by empathy. The findings show that infectious disease vulnerability is conducive to pro-environmental behaviors.

In this study, we analyzed the application of four autosomal kits and the sensitivity of the combined paternity index (CPI) cutoff value (CPI≥10000) in parentage testing. First, 1442 real trios and 803 real duos were tested using the Goldeneye 25A kit. The Goldeneye 25A kit covers the autosomal short tandem repeat (STR) loci of the other three kits, so we calculated the CPI value of every case for the four kits. Second, three complex close relative kinship cases were also analyzed to evaluate the application of the CPI cutoff value. The CPI values of all trio cases were higher than 10000 using the four kits; the CPI values of all duo cases were higher than 10000 using the Goldeneye 25A kit; and the CPI values of a portion of the duo cases were lower than 10000 using the other three kits. In the three complex close relative cases, the alleged father or mother was not excluded using 40 autosomal STRs. Adding X chromosome short tandem repeats (X-STR) and samples of biological fathers or mothers, the conclusions were confirmed. The four kits were adequate to draw conclusions in the trio cases; the Goldeneye 25A Kit was adequate to draw conclusions in the duo cases; and the other three kits were not sufficient for a portion of the duo cases. The CPI cutoff value was sensitive for real trio and duo cases. In complex close relative kinship cases, high CPI values may result in false conclusions.

The core component, TBM cutterhead, bears a multi-directional impact load because of its direct contact with rock during tunneling. Unreasonable cutter design and parameter set lead to severe vibration or abnormal injury during excavation, seriously affecting the efficiency of the TBM tunneling. Therefore, study of cutterhead dynamics response under impact loads is one of the core content of TBM system design. TBM multi-degree-of-freedom coupled dynamic model contains different geological conditions, cutter speed, body mass, time-varying mesh stiffness, transmission error, etc. A method is proposed to solve the problem based on Newmark algorithm, which further improves the solution efficiency. A tunneling field test was conducted, and the results verify the correctness of the model and the simplified cutter system. The simulation results of the Dahuofang project show that: ➀ The calculation process of Newmark is simplified, the calculation speed increased 3-4 orders of magnitude higher than Runge-Kutta method, while the solving time was reduced from 2.6e5 s to 155 s under the same precision; ➁ Compared with the results of two kinds of rock with compressive strength 150 MPa and 95 MPa, the translational vibration amplitude ratio is 3.33 and axial vibration amplitude ratio is 2.08. It indicates that as the rock compressive strength increases, the growth of the cutterhead’s vibration amplitude increase accelerated, rather than proportional increases; ➂ The vibration decreases along with the cutter speed becomes larger and the system becomes stabilized when the cutterhead speed turns into 4r/min. The cutter head speed clearly affects torsional, lateral and longitudinal vibration. The change rate has reached 0.53-0.61. Therefore, TBM should choose the right cutter speed to avoid bearing damage, seal failure and other serious accidents; 4 The translational vibration of components decreases with the components’ mass increase. It has the greatest impact on the horizontal and vertical vibration of the big ring. The vibration changing rate of the big ring reaches 0.31. The big ring has almost no effect on the axial vibration and overturn, but the energy consumed on rock cutting will be reduced as the mass increases. Body weight should be chosen reasonably considering vibration,construction economy and internal excitation of parameters. The above conclusions provide a theoretical basis for TBM dynamics optimization design, vibration control and cutterhead architecture design.

In engineering, solving divergence and long solving time often occurs when solving large complex dynamic equations. Comparative analysis of Newmark and Rungekutta method fora complex dynamic model can provide a theory basis for the selection of numerical integration method when solving complex dynamic equation. The comparative analysis on the solving precision and solving time by Newmark method and Rungekutta method for calculating a same complex dynamic equation is carried out. The calculation results show that the response results by these two methods are in strong consistency. But the Newmark method shortens the solving time by at least 3 orders comparing that of Rungekutta method. Furthermore, the response displacement by Newmark method in different integration steps is obtained. The results indicate that the response results become stable with integration step continues reducing under 0.1.

In order to simulate the Stirling engine more easily, the stiffness and damping ratio of the crankshaft bearing are assumed to be steady-state in the research before, but this assumption is contrary to the real condition. Therefore, in this paper, a time-varying stiffness and damping ratio of the crankshaft bearing simulation method has been proposed. Compared with the simulation results of the crankshaft bearings with constant stiffness, the speed fluctuation coefficient of output shaft and crankshaft in time-varying stiffness model is increased by 10%, 24.6% and 13.7%; the vibration displacement of the center mass of output shaft is decreased by 3.0%; the average dynamic load on airframe is increased by 47.9%. From the simulation results, it is found that the time-varying stiffness and damping ratio of the crankshaft bearing is significant to the characteristics of the Stirling engine dynamic response.

To study the multi-axis low-cycle creep/fatigue life of high-pressure turbine blades, a multi-axis low-cycle fatigue life prediction model based on a new critical plane damage parameter is proposed in this paper. Firstly, based on the thermal-structural coupling analysis of high-pressure turbine blades, the law of stress-strain distribution under the complex load of centrifugal load, temperature load and the aerodynamic load is obtained. Secondly, the multi-axis low-cycle fatigue life prediction model and the L-M equation are applied to predict the fatigue life and creep life of blade respectively. Furthermore, different experimental loading schemes are used to study the fatigue damage mechanism for the creep/fatigue interaction under high temperature condition, and a creep/fatigue interaction life prediction model is simultaneously provided. And finally, the experiment results demonstrate the rationality of the multi-axis low-cycle fatigue life prediction model and the creep/fatigue interaction should not be ignored.

A multi-coupling dynamic model for the Tunnel Boring Machine (TBM)’s main support system was established with consideration of the open-type TBM closed chain support form and the multi degree of freedom (DOF) coupling relation. A multi-position dynamic strain test was carried out based on practical engineering. By using the data as a mark of the dynamic load at key parts of the system, the dynamic model was calibrated. Compared with the measured data, the error of the calculated strain values was less than 25%. The results calculated by this model show that the load of the system presents the characteristics of low frequency and periodicity. The transfer law of the load along the main structure was revealed, and the shield support and main thrust cylinder were determined as the main supporting parts that affected the unbalanced load of the key parts of the support system. The influence of the main support on the dynamic load of the main support structure was studied. This study provides a basis for the system's damage-resistant structural design and evaluation of the TBM performance in tunnel construction.

Super-resolution method based on sparse reconstruction is an effective way to deal with the closely spaced objects problem, but when the targets in a noisy environment, the noise will cover over the entire field, leading to the sparsity feature of the original scene is destroyed. Aiming at this phenomenon, this paper proposed a super-resolution method which has the adaptative reconstruction ability in noisy environments, this method takes full advantage of the structural characteristics of the sensor and the reconstruction algorithm parameters, through the establishment of infrared imaging model of the observed signals and pixel meshing, establishment of the position and amplitude of the closely spaced objects of sparse representation, and using the point spread function of the optical system to construct over-complete dictionary, the last step is making the reconstruction parameters in a reasonable range through controlling the ratio of non-zero elements in the rebuilt scene, so as to achieve the purpose of removing noise interference and reconstruction of sparse targets accurately. Simulation results show that the proposed method with adaptive reconfiguration in noisy environments.

At present, there are various methods to compute the infrared radiation characteristics of exhaust plume of the liquid rocket engine. Though they are different in computational complexity. Their ideas and methods are alike. This paper focuses on the computation methods of exhaust plume’s flow field, spectral parameters and radiation transfer equation. Comparison, analysis and conclusion of these methods are presented. Furthermore, existing problems and improvements of them are proposed as well.

The damage in driving system's core part of TBM caused by pinions' asymmetrical load is very serious. The traditional design lacks the coupling relationship between the mechanical and control system, which leads to the bottleneck of the TBM's driving system's symmetry. This paper considers the dynamic character and control system of the TBM's driving system. An electromechanical coupling model is proposed based on torque's in-time interactive. Take the engineering project as example, the calculation was proceeded based on the original model. The result shows that after a gear frequency cycle, the torque of the motor with maximum load increased by 4.46%, and the minimum one decreased by 9.00%.

This paper classifies the TBM thatmostly used in the practical engineering into TBM 1 and TBM 2, and comprehensively analyses the difference of cutter layout strategy, pinion layout strategy, shield support structure, etc between TBM 1 and TBM 2.The vibration periodicity of TBM 2 significantly reduces. The influence of shield vertical support on the horizontal and vertical vibration of TBM 2 is analyzed. The results show that settinga vertical support at the bottom of the shield reduces the TBM cutterhead vibration by about 12%.

This paper through Comparative analysis of Newmark and Rungekutta method for a complex dynamic model can provide a theory basis for the selection of numerical integration method to solve complex dynamic equation. The comparative analysis on the solving precision and solving time by Newmark method and Rungekutta method for calculating a same complex dynamic equation is carried out. The results indicate that the response results become stable with integration step continues reducing under 0.1.