Abstract
The regulation of heterogeneous material properties to enhance the peroxymonosulfate (PMS) activation to degrade emerging organic pollutants remains a challenge. To solve this problem, we ...synthesize S−scheme heterojunction PBA/MoS
2
@chitosan hydrogel to achieve photoexcitation synergistic PMS activation. The constructed heterojunction photoexcited carriers undergo redox conversion with PMS through S−scheme transfer pathway driven by the directional interface electric field. Multiple synergistic pathways greatly enhance the reactive oxygen species generation, leading to a significant increase in doxycycline degradation rate. Meanwhile, the 3D polymer chain spatial structure of chitosan hydrogel is conducive to rapid PMS capture and electron transport in advanced oxidation process, reducing the use of transition metal activator and limiting the leaching of metal ions. There is reason to believe that the synergistic activation of PMS by S−scheme heterojunction regulated by photoexcitation will provide a new perspective for future material design and research on enhancing heterologous catalysis oxidation process.
This paper presents a new concept for a hybrid trapped field magnet made of second generation high-temperature super-conducting ring-shape magnet and HTS stack tapes. This hybrid trapped field magnet ...has the potential to provide a better magnetic field. This paper focuses on the magnetization properties of this new magnet. First, ultraviolet laser cutting technology was used to prepare the striated HTS tapes. Then both tradition method and "wind-and-flip" method were used to fabricate the ring-shape magnet. After that, basic features of the hybrid trapped field magnet, such as the maximum trapped field and decay rate were quantified by pulsed field magnetization (PFM) experiments. Due to the limitation of PFM method, a more cost-effective magnetization method based on thermal controlled persistent current switch (PCS) was investigated to achieve a higher trapped field. Finally, both numerical and experimental methods were used to analyze the working mechanism of the hybrid trapped field magnet. Conclusions of this paper show that the hybrid trapped field magnet is a potential concept to fabricate low cost, high performance magnets, and the "wind-and-flip" technology combined with PCS technique is a reliable way to improve the working performance as well as reduce the total cost magnetization facilities.
No-insulation (NI) coils made by second-generation (2G) high-temperature superconducting (HTS) tapes have a better thermal stability than traditional coils which wound with insulation. The NI coils ...have been developed and been employed in many superconducting applications such as superconducting motor, transform, and generator. In these cases, the NI coils will inevitably be affected by ac magnetic field. When a superconductor carrying a dc current is exposed to an ac field, a dynamic resistance R dyn will occur and cause significant ac loss. In this paper, R dyn is calculated by field-decay method, which has a wider measurement range and higher accuracy than four-probe method. The correction curve for R dyn with the ratio of operating current and critical current (I op /I c ) is presented. Combining the persistent-current mode (PCM) circuit model of closed NI coil and the correction curve, a predictable simulation model for central magnetic field characteristic of closed NI coil with partial tape exposed to an ac magnetic field is established and verified by experiments.
Closed coils made by second-generation high-temperature superconducting (HTS) coated conductors are promising for superconducting magnets, which operating in a persistent current mode such as MRI, ...NRM, and Maglev. The magnetic field stability for the HTS closed coils after local thermal quench is one of the key indicators to the design of superconducting magnet systems. It significantly affects the operational reliability of superconducting magnets. This paper presents quantitative experiments on the magnetic field stability of a jointless stacked pancake (JSP) coil after local thermal quench. The JSP coil is assembled by stacking double-slit YBCO tapes, which is a true sense of HTS closed coil without any joints. A JSP coil with inner diameter of 30 mm is impregnated by paraffin wax and its central magnetic field stability is measured after various local thermal quench energies. The relationship between quench energy and magnetic field stability time is presented. The magnetic field of the JSP coil will stay stable when quench energy is lower than a threshold value Qm. The magnetic field stability of JSP coils comes from its parallel-structure. Besides, the magnetic field stability of the JSP coil is better than the series-structure closed coil obviously under the same quench energy.
Breast cancer (BC) and thyroid cancer (TC) have the highest rate of incidence, especially in women. Previous studies have revealed that lactate provides energetic and anabolic support to cancer ...cells, thus serving as an important oncometabolite with both extracellular and intracellular signaling functions. However, the correlation of lactate metabolism scores with thyroid and breast cancer immune characteristics remains to be systematically analyzed. To investigate the role of lactate at the transcriptome level and its correlation with the clinical outcome of BC and TC, transcriptome data of 1,217 patients with breast cancer (BC) and 568 patients with thyroid cancer (TC) were collected from The
Cancer
Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets with their corresponding clinical and somatic mutation data. The lactate metabolism score was calculated based on a single-sample gene set enrichment analysis (ssGSEA). The results showed that lactate metabolism-related genes and lactate metabolism scores was significantly associated with the survival of patients with BRCA and THCA. Notably, the lactate metabolism scores were strongly correlated with human leukocyte antigen (HLA) expression, tumor-infiltrating lymphocyte (TIL) infiltration, and interferon (IFN) response in BC and TC. Furthermore, the lactate metabolism score was an independent prognostic factor and could serve as a reliable predictor of overall survival, clinical characteristics, and immune cell infiltration, with the potential to be applied in immunotherapy or precise chemotherapy of BC and TC.
In this study, three-dimensional (3-D) numerical models of resistive joints for ReBCO coated conductors are established in the commercial finite element analysis software COMSOL Multiphysics 5.0. In ...this simplified model, only two ReBCO layers and one/two "connection" layer(s) (i.e., the resistive interlayer(s) sandwiched by two ReBCO layers) are considered. 3-D power-law E-J relationship (where J is the current density, E is the electric field intensity) is employed for superconducting layer and an isotropic bulk resistance is set for the connection layer(s). The interfacial resistances are taken into account by introducing boundary weak contributions. The joint resistance exhibited a non-uniform relationship with the geometry of the joining area. And the joint resistance tended to approach to a lower limit value. Silver diffusion joint samples are fabricated and tested to verify the simulation results and a good agreement is obtained. The above phenomenon is attributed to the highly non-uniform current distribution in the ReBCO layers and therefore in the connection layers. By our simulation, it is found that the criterion value of overlap length (the length of joining area) corresponding to the lower limit of joint resistance is highly related to the resistivity of the connection layer.
Low-resistance joint technology is crucial for high-temperature superconducting (HTS) closed-loop coils that work in persistent current mode. The non-uniform current distribution (NUCD) phenomenon in ...HTS joint has a significant influence on joint resistance, which may lead to a nonlinear relationship between joint resistance Rj and overlap length l (Rj-l curve) instead of following the laws of resistance. In this paper, an arched structure joint made by YBCO tapes has been designed to provide a direct evidence for the NUCD phenomenon inside solder joint. It is found that the current transports mainly at the end of the overlap area and is much different from the regular conductors. The V/I-I method is proposed to measure Rj of solder joints (less than 2 nΩ) with various overlap lengths in order to obtain more precise data. A complete Rj-l curve (l = 5-100 cm) has been successfully illustrated and a nonlinear saturation relationship between Rj and l is presented. The joint resistance tends to approach to a lower limit value about 1.5-1.6 nΩ when the overlap length exceeds 20 cm.
This paper presents a study on the coil voltage of the no-insulation (NI) high-temperature superconductor (HTS) pancake coils during fast discharging operations. Fast discharging tests are performed ...on both a double pancake (DP) and an single pancake (SP) NI coil. The measured coil voltages are compared with that from an equivalent circuit model, which has been widely used in previous studies. A voltage pulse is observed on both the NI coils at the beginning of the fast-discharging operation. It is much higher than that from the modeling. The peak value of the voltage pulse increases linearly with the initial current. Comparison tests show that the coupling iron core has little influence on this coil voltage pulse though the inductance of the coils is enlarged seven times by coupling iron core. This coil voltage pulse shows that, during the fast discharging operation, the NI coil has a much higher turn-to-turn resistivity at the beginning stage than that in following process. Since the coil voltage pulse can be 600 times of the modeling estimation, it may be a potential risk to the coil protection system and measuring instruments. Therefore, special attentions are required on this aspect in the design of NI magnets.
Silver diffusion method is a promising candidate for joining the second generation high temperature superconducting tapes that can achieve a joint resistance of nΩ level while retaining full critical ...current. In this study, silver diffusion joints with joint resistance as low as <; 2 nΩ was demonstrated. The performance of silver diffusion joints under axial tension load, which is considered as a key parameter for their practical applications, was also systematically studied. It was investigated that the nominal critical axial tensile stress of the unlaminated silver diffusion joint fabricated by the coated conductor tapes from Shanghai Superconductor Co., Ltd. was in the range of 430-480 MPa, which is significantly lower than that of the single tape (approximately 590 MPa) and could hardly be improved by increasing the overlap length from 1 to 10 cm or by modifying the configuration from the lap-type to the enhanced bridge-type. According to the experimental results, the failure mechanism of silver diffusion joints under tensile stress was discussed. Based on which, a post-lamination process was proposed to alleviate the local stress concentration. The laminated silver diffusion and single straight tape exhibited consistent behavior under axial tension load and, therefore, the same critical axial tensile stress.
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•Nitrifying rate increased with the increase of aerobic/anoxic alternation number.•Aerobic/anoxic alternation affected nitrifying and denitrifying enzyme activity.•Aerobic/anoxic ...alternation caused the variation of microbial community.•Aerobic/anoxic alternation resulted in the change of the functional genes abundance.
The performance, microbial community and functional genes of a sequencing batch biofilm reactor (SBBR) were investigated in treating mariculture wastewater under different aerobic/anoxic alternation number. The removal efficiency of chemical oxygen demand (COD) and NH4+-N kept at 95.66 ± 1.83 % and 90.28 ± 2.42 % under aerobic/anoxic alternation number between 1 and 4. The total nitrogen (TN) removal efficiency gradually decreased from 94.45 ± 1.12 % to 83.06 ± 1.25 % with the increase of aerobic/anoxic alternative number from 1 to 4. The nitrification rates and their corresponding enzymatic activities increased slightly with the increase of aerobic/anoxic alternation number, whereas the denitrifying process had the contrary results. The variation of aerobic/anoxic alternation number obviously affected the microbial diversity and abundance. The microbial network structure and keystone taxa were different under different aerobic/anoxic alternation number. The functional genes abundance for the denitrification pathway decreased with the increase of aerobic/anoxic alternation number.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
