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The effects of the ordered and disordered arrangements of elements on radiation-induced defects production and evolution in NiFe alloys were investigated through atomistic simulations. Results present a sluggish evolution of the overall microstructure in ordered L10 NiFe. Although the disordered phase has fewer Frankel pair accumulation in cascade simulation attributed to the low thermal conductivity reduced by the intrinsic chemical disorder, the difference is negligible when PKA energy increases because of the direct formation of clusters. Interstitial diffusion is restricted in the ordered phase, where Ni and Fe layers are alternately arranged. This condition delays interstitials accumulation and leads to the formation of more Shockley partial loops rather than Frank loops which favor in the disordered phase. The higher stacking fault energy in the ordered phase renders it difficult to form stacking fault tetrahedra

Antibiotics are infiltrating the natural environment worldwide owing to their extensive use, and this proliferation poses significant threats to human health and ecological safety. Consequently, more efficient approaches for antibiotic detection and removal are urgently needed. Motivated by the success of graphene, many two-dimensional materials beyond graphene (2DMs-bg) with unique physiochemical properties have garnered tremendous interest and been applied in many fields, including antibiotic pollution treatment. In this review, we summarize recent advances in the application of five kinds of 2DMs-bg, including MoS2, layered double hydroxides (LDHs), graphitic carbon nitride (g-C3N4), hexagonal boron nitride (h-BN), and transition metal carbides or nitrides (MXenes) to detect, adsorb, and degrade antibiotics. In antibiotic detection applications, only MoS2 and g-C3N4 are used, and the research on these two 2DMs-bg is still in the initial stages. Additionally, MoS2, LDHs, and h-BN have been used for antibiotic adsorption in few studies. Although there are few published results, h-BN has been shown to have a better adsorption capacity than most current graphene-based adsorbents. MoS2, g-C3N4, LDHs, h-BN, and MXenes have all been applied for antibiotic degradation. Among them, MoS2 and g-C3N4 have demonstrated promising elimination capacities, which are better than those of graphene. Finally, we present persistent challenges and propose future perspectives for this avenue of ongoing research.

One of the main reasons for the stability issue of inorganic perovskite quantum dots (PQDs) is the fragile protection of surface ligands. Here, an armor-like passivation strategy is proposed to improve the comprehensive stability of PQDs via a solvothermal fabrication method. That is, forming an armor-like protection layer for every single surface point by introducing coupling ligands with strong affinity (both L and X type ligands). The interactions between ligands via hydrogen bonds and strong affinity of ligands to surface atoms are evidenced by 1H-nuclear magnetic resonance measurements and Fourier transform infrared spectroscopy. As a result, long-term storage stability, high quantum yield, good water resistance, and good radiation hardness of PQDs are achieved. More than 60% of the radioluminescence intensity of the PQD film could be retained under continuous irradiation of 42 kGy. The output power can even be increased by 34.48% compared with the battery without PQD film. This armor-like passivation strategy also provides good reference for the stability improvement of both light-emitting and photovoltaic devices.

Accurate localization of radioactive materials is crucial in homeland security and radiological emergencies. Coded-aperture gamma camera is an interesting solution for such applications and can be developed into portable real-time imaging devices. However, traditional reconstruction methods cannot effectively deal with signal-independent noise, thereby hindering low-noise real-time imaging. In this study, a novel reconstruction method with excellent noise-suppression capability based on a multi-layer perceptron (MLP) is proposed. A coded-aperture gamma camera based on pixel detector and coded-aperture mask was constructed, and the process of radioactive source imaging was simulated. Results showed that the MLP method performs better in noise suppression than the traditional correlation analysis method. When the Co-57 source with an activity of 1 MBq was at 289 different positions within the field of view which correspond to 289 different pixels in the reconstructed image, the average contrast-to-noise ratio (CNR) obtained by the MLP method was 21.82, whereas that obtained by the correlation analysis method was 5.85. The variance in CNR of the MLP method is larger than that of correlation analysis, which means the MLP method has some instability in certain conditions.

Interstitial strengthening is one of the main approaches to improving the mechanical properties of high-entropy alloys (HEAs), but its effects on the irradiation resistance of HEAs need further study. Here, we investigated the irradiation-induced defects and swelling of Fe38Mn40Ni11Al4Cr7 HEAs with different carbon contents under 5 MeV Xe23+ irradiation at 300 °C and 500 °C. Results show that the irradiation-induced swelling was significantly suppressed as the carbon content increased. Under the observation of TEM, the size of irradiation-induced dislocation loops also decreases with increasing carbon content. By comparing the effects of carbon content at different temperatures on the evolution of defects, the pinning effect of interstitial carbon on irradiation-induced defects of HEAs was proposed and analyzed. Carbon atoms, which are stabilized in the octahedron clearance of HEAs with FCC structure, not only promote the recombination of point defects by enhancing the sluggish diffusion effect of HEAs, but also pin the common 1/3 faulted loops caused by irradiation. This pinning effect is the main mechanism of interstitial carbon for improving the irradiation resistance of HEAs below 300 °C. In summary, this study provides an essential experimental basis for the irradiation effects of carbon-doped HEAs and strives to reveal the effect of interstitial carbon on irradiation-induced defects at different temperatures.

High-performance nanofiltration (NF) membranes with simultaneously improved antifouling and separation performance are of great significance for environmental water purification. In this work, a high-performance thin-film composite (TFC) NF membrane (TFC-Ca) was constructed through in-situ incorporation of calcium bicarbonate during interfacial reaction. The surface morphology and chemical structure of the TFC-Ca membrane were systematically investigated by FTIR, XPS, AFM, and SEM. The results indicated that the surface characteristics of the pristine NF membrane were greatly changed by the incorporation of calcium bicarbonate. The TFC-Ca membrane exhibited improved hydrophilicity, narrowed pore size, declined negative charge, and increased surface area. Compared to the control membrane, the TFC-Ca membrane possessed a much greater water permeability and higher molecule rejections. For the TFC-Ca membrane, an optimized water permeance of 13.4 ± 0.3 L m−2 h−1 bar−1 with 99.9% Na2SO4 rejection was obtained. Impressively, the TFC-Ca membrane exhibited excellent antifouling performance during 5 cycles of humic acid fouling tests. A satisfactory flux recovery up to 90.0% was achieved after physical cleaning for the optimized membrane. Furthermore, the TFC-Ca membrane also presented superior performance stability when treated with strong acid and chelating agents for 7 days. Overall, this facile preoccupation strategy via in-situ incorporation of calcium bicarbonate allows the fabrication of high-performance TFC membranes with outstanding separation and antifouling properties.

X-ray communication (XCOM) is an advanced space-communication technology. The high penetration of X-ray enables XCOM to achieve lower signal attenuation than conventional optical communication in Martian dust storm. This study provided a demonstration of this approach based on simulation methods. The transmission properties of X-ray beams in Martian non-dust storm weather were evaluated based on the MCNP5 code. Results demonstrated that the X-ray beam can transmit through a long-distance in Martian atmosphere. Moreover, on the basis of the anomalous diffraction and Mie theory codes, the transmission properties of X-ray and optical links in Martian dust storm were evaluated. Results showed that the dust attenuation of the X-ray links were significantly lower than that of optical links. Moreover, the penetration and communication performance of X-ray links were evaluated and compared with the optical link, considering atmospheric and dust attenuation. Results indicated that XCOM can be used to establish a low-BER communication link between rovers, and from the rover to the orbiter, in Martian dust storm.

To efficiently improve the performance of ultrafiltration (UF) membrane for drinking water treatment, carbon nanotubes (CNTs) and carbon nanofibers (CNFs) were utilized as pre-deposited coating layers on membrane surface. A comparative study between these two carbon nanomaterials for enhancing pollutants removal and mitigating membrane fouling induced by natural organic matter (NOM) was carried out. The surface morphologies were characterized by scanning electron microscopy, and the results indicated that the CNTs coating layer was more dense and homogeneous with a smaller pore size than that of CNFs. The removal and antifouling performance of CNTs/CNFs coated membranes were investigated with typical NOM, i.e., humic acid, bovine serum albumin, sodium alginate, as well as natural surface water. The results showed that the presence of coating layers was very effective to improve the rejection rate of NOM, among which CNTs exhibited significant better performance than CNFs. The fouling control performance was influenced by the NOM fraction and coating mass (6–50 g/m 2 ). Generally, CNTs coating layer was more efficient in alleviating both reversible and irreversible membrane fouling, while CNFs exhibited limited effect on irreversible fouling control. Both pre-adsorption and size exclusion contributed to the rejection of membrane foulants, thus reducing the organics directly contacted with the underlying membrane. In natural surface water treatment, the pre-deposited coating layers significantly delayed the transition of fouling mechanisms from pore blocking to cake filtration. The experimental results were expected to illustrate the feasibility of pre-deposited CNTs/CNFs layers for enhancing membrane performance during drinking water treatment.

Rapid nuclide identification is crucial in improving the performance of radioactivity monitoring. Rapid measurement of considerable fluctuation and noise in gamma-ray spectra causes difficulties in nuclide identification. Current methods require noise removal, background subtraction, feature extraction, and the information of low-count channels may be lost during these processes. In this study, we developed a rapid nuclide identification method based on convolutional neural network (CNN). A dataset was constructed using simulation method for CNN training. The algorithm was evaluated with different gamma-ray spectra measured under different times, distances, and mixed radioactive sources. Results showed that the algorithm has high recognition accuracy for low count rate gamma-ray spectra, and which can be used to improve the identification performance of rapid radiation monitoring.

An approach is presented for eliminating communication blackout caused by the plasma sheath encountered during the Mars atmospheric entry phase. On the basis of the high penetration of X-ray beams,...

Nickel–graphene nanolayers with high-density interfaces are expected to have excellent resistance to helium (He) embrittlement and proposed as candidate materials for molten salt reactor systems. However, He irradiation effects on nickel–graphene nanolayers remains poorly understood at present. In this work, the influence of a nickel–graphene interface (NGI) on the nucleation and growth of He-related clusters was studied by using atomistic simulations. The NGI reduces formation energies and diffusion energy barriers for He-related clusters. The reduction makes He-related clusters easily be trapped by the interface, thus leading to significant segregation. Consequently, He concentration in the bulk is considerably reduced, and the nucleation and growth rates of He-related clusters in the bulk are delayed. Owing to the high mobility of He-related clusters at the NGI, these clusters easily coalesce to form larger clusters than those in the bulk. A reasonable design of nanolayers may promote He releasing from materials. Results of the current study can provide fundamental support for the service life assessment of nickel–graphene nanolayers in extreme environments.

There is an impedance conflict between the fundamental harmonic of ${f}_{2}$ and the second of ${f}_{1}$ if ${f}_{2}\,\,{=}\,\,{2}{f}_{1}$ . In this brief, a methodology employing the harmonic active load modulation (HALM) technique is utilized for solving this problem. A main power amplifier and an active load modulator constitute the overall circuit. This technique transforms the second harmonic load impedance to the optimum by injecting second harmonic power in the lower band. In order to improve the overall efficiency, a method of searching optimal location parameter is proposed to achieve the minimum extra power in harmonic injection. A power amplifier (PA) working at 1.7 and 3.4 GHz is fabricated for validation. At 1.7 GHz, the HALM technique brings an improvement of 14% in overall efficiency and an increase of 0.7 dB in output power. As for 3.4 GHz, the fabricated PA delivers overall efficiency of 78.5% and output power of 41.3 dBm without HALM.

Organic-inorganic halide perovskite (OIHP) has attracted tremendous attention due to its potential applications in optoelectronics such as light emitting device and photodetector. Here, we have grown high quality CH3NH3PbBrxCl3-x perovskite single crystals and investigated the luminescence mechanism of these materials. The results indicate that optical properties of CH3NH3PbBrxCl3-x perovskite materials are strongly depend on the temperature and the dope concentration. Free exciton recombination emission has dominant contribution to luminescence spectra of materials at orthorhombic structure, as bound exciton recombination emission to the spectra of materials at cubic structure. Based on temperature-dependent photoluminescence, the exciton binding energy of CH3NH3PbCl3 and CH3NH3PbBr0.3Cl2.7 are calculated as about 22.9 meV and 27.1 meV, respectively.

In this paper, the effects of a 150 keV proton radiation on a GaAs sub-cell of GaInP/GaAs/Ge trip junction solar cells and its radiation damage were studied. The degradation behavior of the solar cells was analyzed by theoretical device modeling combined with electro-optical characterization techniques such as external quantum efficiency, IV measurements, and photoluminescence (PL). The degradation of cell output parameters by protons was plotted as a function of the displacement damage dose. The results show that the short-circuit currents degrades less than open-circuit voltages because the base region of GaAs is severely damaged. The PL results indicated that proton irradiation exerted destructive effect on the photoelectric properties of the material. Such destructiveness was due to the numerous defects introduced by proton irradiation, which destroys the integrity of the lattice space, resulting in a decrease in the diffusion length of the minority and an increase in the surface recombination velocity. By COMSOL simulation analysis, it is found that the reason of radiation degradation of GaAs is the decrease of minority carrier time after irradiation and simulation results show that the PL results are in good agreement with the simulation results which can provide a method for the calculation of internal defects and minority carriers in multi-junction solar cells.

A high-performance nanofiltration (NF) membrane with simultaneously improved desalination and antifouling properties while maintaining regeneration ability is highly desirable in water treatment. Surface modification is an effective approach to enhance the performance of NF membranes. In the present study, a multifunctional thin-film composite NF membrane (Fe-TFC) was fabricated via coating a regenerable ferric ion-tannic acid (FeIII-TA) layer on the nascent polyamide membrane surface. The Fe-TFC membrane exhibited enhanced hydrophilicity, smaller pore size, and lower negative charge compared with the control membrane. The salt rejections and selectivity of divalent to monovalent ions were greatly improved with only a slight decrease in water permeability due to the presence of the coating layer. Meanwhile, dynamic fouling tests with humic acid demonstrated that the Fe-TFC membrane possessed an enhanced antifouling property and excellent flux recovery rate. After coating, the normalized water flux and flux recovery of the Fe-TFC membrane increased from 0.02 to 0.26 and 32.1 to 76.4% at the end of five cycles of fouling tests, respectively. In addition, the resultant membrane exhibited excellent durability and stability under harsh conditions for ∼10 days. Interestingly, the fouled coating layer can be easily removed by HCl cleaning and regenerated through an in situ strategy. Consequently, the regenerated membranes presented stable antifouling properties and desalination performance after several times of regeneration. It was demonstrated that the unique feature of FeIII-TA networks enables the coating layer to act as a protective layer for the underlying polyamide membrane, leading to the high performance of the composite membrane. This study provides a new insight for surface functionalization and easy regeneration of the TFC nanofiltration membrane in water treatment technology.

The application of liquid scintillators as energy conversion materials in nuclear batteries was proposed. By introducing liquid scintillators, the output properties of radioluminescence (RL) nuclear batteries based on different liquid scintillators were investigated via low-energy X-ray. Results indicated that the values of short circuit current Isc and maximum output power Pmax increased as the X-ray intensity increased, and the output power of nuclear battery with Ultima Gold liquid scintillator was greater than those of batteries with Emulsifier-Safe or Bioscint liquid scintillator under excitation condition of 25 kV tube voltage. To analyze the RL effects of the liquid scintillators under X-ray excitation, we measured the RL spectra of the different liquid scintillators. Considering luminescence utilization in batteries, the surface of the quartz cuvette was covered with Al film. Al is a high-performance reflective material that can increase the scintillation light released by Ultima Gold, reaching the GaInP/GaAs/Ge device. After covering a thin Al film, the output power of the battery was significantly improved under X-ray excitation.

Highly luminescent CsPbBr3 perovskite quantum dots (QDs) are very attractive for applications in power-generating devices. The CsPbBr3 QD solution and its corresponding solid films were satisfactor...

The possibility of utilizing blended wastewaters from raw anaerobic digestion effluent (RADE) and rainwater (RW) was investigated for cost-efficient Chlorella vulgaris (C. vulgaris) cultivation in photobioreactor (PBR). Two-sequencing batch PBRs were started-up with RADE and mixed wastewater (40% ADE + 60% RW). The result indicated that C. vulgaris growth and contaminants removals were inhibited due to the high concentration of nutrient and organic pollutants in PBR (RADE). Comparatively, PBR (ADE + RW) obtained satisfying treatment efficiencies with the maximum removals of NH4+-N (94.61 ± 1.83%), PO43−-P (95.71 ± 1.73%) and COD (86.72 ± 1.72%). RW supplemented trace elements (Fe, Mn, Zn, Cu), which accelerated C. vulgaris photosynthesis with high lipid productivity accumulation (65.72 ± 1.98 mg/L⋅day) in PBR (ADE + RW). This study firstly demonstrated the potential of using mixed wastewater (ADE + RW) for cost-efficient C. vulgaris cultivation with simultaneous actual ADE wastewater treatment in PBR.

Space microscientific instruments require power supplies that are sustainable, stable, and long life. A micro-radioisotope thermoelectric generator can be used as a sustainable long-life power supply for low-power-device applications. This study innovatively proposes micro stacked-integrated annular-radial radioisotope thermoelectric generator and prepares a multilayer prototype to drive various LEDs as a demo. A high-performance micro-radioisotope thermoelectric generator module based on a flexible printed circuit is designed and prepared by screen printing. At a temperature difference of 48 K, the voltage density is 2.21 V cm−3, and the power density is 514.25 μW cm−3. When loaded with 1.564 W heat sources, a 10-layer prototype generates an open-circuit voltage of 0.815 V, a short-circuit current of 0.551 mA, and an output power of 114.38 μW. The maximum series voltages are 0.929 and 2.2 V for the 10- and 30-layer prototypes. The short-circuit current of the 5-layer parallel prototype is 1.18 mA, and the voltage is hardly reduced. In the impact evaluation on ambient temperature, the electrical output of the prototype increases with increased temperature (−30 °C–120 °C). In the different configurations of the prototype, the 10-layer, 30-layer series, and 5-layer parallel prototypes are proposed, thereby providing considerable output. The developed generator is expected to provide reliable power support for space microscientific instruments.

Selective laser melting (SLM) provides a novel path to fabricate austenitic stainless steels used in the nuclear reactors. Meanwhile, obvious differences in the microstructures of materials present between SLM and conventional process, which causes a discrepancy in the helium (He) tolerance. In present work, an austenitic stainless steel (type 316L) manufactured through SLM was irradiated by He ions at 450 °C with the concentration approximately 0.8% and then characterized via multiple methods. Results showed the special microstructure containing cellular sub-grains and nano-oxide inclusions, which formed owing to the SLM process, still distributed in post-irradiated samples. A decrease in the bubbles density, swelling rate, and hardness change has also been observed compared with conventional stainless steel. The interfaces provided by the sub-grain boundaries and nano-oxide inclusions act as effective trap sites for helium bubbles, which contributed to the enhancement of helium tolerance.

A concept of molten salt fast reactor (MSFR) was proposed in EVOL to burn transuranium element discharged from pressurized water reactors. MSFR is featured by fast spectrum and using liquid fuel salt containing UF 4 or ThF 4 . Some issues are presented, for instance, global material arrangement affects the local neutron spectrum due to long neutron free path, and fluoride salt (LiF-BeF 2 ) has nonnegligible thermal neutron scattering effect. Thus, lattice code prepared for thermal-spectrum reactor is not suitable for MSFR calculation. In this study, “two-step” calculation scheme combining Monte Carlo method and deterministic method was prepared for MSFR calculation. A tool named TRANS was developed to transfer tally data from an open source Monte Carlo code OpenMC into few-group homogenized cross-sections, and one benchmark based on pressurized water reactor and two types of model based on MSFR were used for verification. Besides, the applicability of few-group parameters generated by different model to MSFR whole-core calculation was analyzed. Finally, MSFR neutronics characteristics at steady-state were calculated using MOREL. The results show that the few-group parameters generated by one-dimension (1D) and two-dimension (2D) model are correct, and it is feasible to use OpenMC to generate few-group parameters. In case of 1D homogenization model, few-group parameters by 1D model (b) can give more accurate results both for eigenvalue and flux distribution. In MSFR whole-core calculation, using few-group cross-sections generated by 2D model has better accuracy in flux distribution, however, using few-group cross-sections generated by 1D model has better accuracy in k eff calculation. Moreover, the neutronics parameters of MSFR calculated by MOREL code agree well with that by other institutes.

During the 2018 IEEE Microwave Theory and Techniques Society (MTT-S) International Microwave Symposium (IMS2018) in Philadelphia, Pennsylvania, the Student Design Competition (SDC) for a high-efficiency power amplifier (PA), sponsored by the MTT-S Technical Committee on Microwave High-Power Techniques, celebrated its 14th anniversary. This competition aims to challenge the maximum poweradded efficiency (PAE) of PAs without compromising linearity performance.

Given independent and flexible power supply requirements of space apparatus, miniaturized radioisotope thermoelectric generators are currently playing an increasing role in space power systems. This study creatively proposes a miniaturized integrated-design radioisotope thermoelectric generator based on concentric filament architecture and is the first to formulate a practical battery entity. When heat source temperature is 398.15 K, the maximum open-circuit voltage of 418.82 mV and the maximum output power of 150.95 μW are obtained. The COMSOL is used to simulate precisely the thermoelectric conversion process and optimize the structural size of the radioisotope thermoelectric generator. The optimal results are obtained when the ratio of N- to P-type circle radius and the thermoelectric filament's length are 0.1 and 20 mm, respectively. In this case, the battery obtains the maximum output power of 423.50 μW and open-circuit voltage of 605.84 mV when heat source temperature is 398.15 K. When the thermoelectric filament's curvature is 170°, the electrical density value increases more remarkably than that of 0°. Its effective open-circuit voltage density and output power density are 73.79 mV cm−3 and 53.76 μW cm−3, respectively. The optimized miniaturized radioisotope thermoelectric generator is able to provide power support for space microelectronic devices.

In order to alleviate the membrane fouling, a short flow drinking water process coupled the continuous sand filtration (CSF) to ultrafiltration (UF) was developed to treat the micro-polluted surface water and the membrane fouling mechanism was further discussed. The results indicated that the CSF process significantly enhanced the removal of ammonia (NH4+-N), accounting to an average removal of more than 70%. Furthermore, the natural organic matters (NOM) were also efficiently removed, with CODMn, UV254 and DOC reduced by approximately 30%, 17% and 18%, respectively. After 2 months of operation, the biological activity developed gradually within the CSF, which sparked an efficient removal performance of Fe and Mn. Besides, three dimensional fluorescence parallel factor analysis (PARAFAC) was employed to trace and characterize membrane fouling and a significantly positive correlation between the fluorescent foulants and irreversible fouling was observed. In addition, further simulations indicated that cake layer formation should be responsible for the trans-membrane pressure (TMP) increase. In order to gain a deep insight to the membrane fouling, the composition of foulants in the chemical backwash water was characterized, and humic substances and metal ions (i.e. Fe, Mn, Ca and Mg) were the main components, which demonstrated that the irreversible membrane fouling should be related to the synergistic effects of inorganic ion precipitates and humic substances. Overall, coupling CSF to UF filtration can significantly enhance its removal performance and control the membrane fouling, which is expected to be a promising alternative based on the principle of aquatic ecosystems for the micro-polluted raw water.

Oxidants are routinely employed to remove manganese from groundwater deeply, but the conversion pathway of manganese in the process still needed to be explored. In this study, potassium permanganate and sodium hypochlorite were introduced to explore their start-up effect on sand filters in treating high concentration of manganese (1.42–1.94 mg/L). The addition of potassium permanganate would effectively enhance the manganese removal (>97%) and significantly shorten the start-up period (36 days) compared to sodium hypochlorite-added filter (90 days). A good correlation between manganese deposition concentration and manganese removal rate was obtained, which indicated that the removal of manganese in pre-adding oxidants sand filters was dominated by adsorption and auto-catalytic oxidation processes, where δ-MnO2 played a crucial role and the contribution of bacteria was negligible. The addition of potassium permanganate facilitated the production of MnO2 and promoted the conversion of Mn(II)-γ-MnO2-δ-MnO2/todorokite during the 120-day operation. Besides, the residual Mn(II) contributed to converting the freshly generated MnO2 by pre-adding oxidants into active MnOx. XPS results demonstrated the co-existence system of Mn(II), Mn(III) and Mn(IV) in δ-MnO2. The proportion of Mn(III) with high catalytic oxidative activity in potassium permanganate-assisted formed MnOx (57%) was much higher than in sodium hypochlorite-assisted formed MnOx (22%). These findings have practical significance to develop new strategies for rapid, safe and deep removal of manganese.

Though sulfamethoxazole (SMX) degradation at the low or medium concentration (SMX30 mg/L) has been reported in the microbial fuel cell (MFC), further exploration is still urgently required to investigate how the high concentration of SMX affect the anode biofilm formation. In this study, the degradation mechanism of SMX and the response of microbial community to SMX at different initial concentrations (0, 0.5, 5 and 50 mg/L) were investigated in MFCs. The highest SMX removal efficiency of 98.4% was obtained in MFC (5 mg/L). SMX at optimal concentration (5 mg/L) could serve as substrate accelerating the extracellular electron transfer. However, high concentration of SMX (50 mg/L) conferred significant inhibition on the electron transfer with SMX removal decline to 84.4%. The 16S rRNA high-throughput sequencing revealed the significant shift of the anode biofilms communities with different initial SMX concentrations were observed in MFCs. Thauera and Geobacter were the predominant genus, with relative abundance of 31.9% in MFC (50 mg/L SMX) and 52.7% in MFC (5 mg/L SMX). Methylophilus exhibited a huge increase with the highest percentage of 16.4% in MFC (50 mg/L). Hence, the functional bacteria of Thauera, Geobacter and Methylophilus endowed significant tolerance to the selection pressure from high concentration of SMX in MFCs. Meanwhile, some bacteria including Ornatilinea, Dechloromonas and Longilinea exhibited a decrease or even disappeared in MFCs. Therefore, initial concentrations of SMX played a fundamental role in modifying the relative abundance of predominant populations. This finding would promote theories support for understanding the evolution of anode biofilm formation related to the different initial concentrations of SMX in MFCs.

A photobioreactor (PBR) coupled with ultrafiltration (UF) system was developed with goals of microalgae cultivation, harvest, and membrane fouling control in the anaerobic digestion effluent purification. Firstly, three-sequencing batch PBRs were started-up with suspended Chlorella vulgaris (C. vulgaris, SCV), immobilized C. vulgaris (ICV) and immobilized C. vulgaris with powdered activated carbon (ICV + PAC). The results exhibited high DOC degradation (66.61%-84.35%) and completely nutrients (nitrogen and phosphorus) removals were attained in PBRs. This indicated bacterial-microalgal consortiums enhanced biodegradation and PAC adsorption accelerated photodegradation. During the microalgae harvest by UF, immobilized microalgae beads protected cells integrity with less debris and intracellular/extracellular organic matters lysis. Moreover, the cake layer in ICV + PAC could even serve as a dynamic layer to entrap the residual pollutants and control membrane fouling. Hence, membrane fouling mitigation and ADE purification were realized during the microalgae harvest process in the ICV + PAC.

Metal–graphene nanocomposites are expected to have excellent radiation tolerance, and may become a candidate structural material for advanced fission reactors. Nevertheless, whether the structural disorder of graphene introduced by preparation or irradiation can strongly affect the radiation tolerance of the composites is still unclear. Here we investigate the radiation tolerance of nickel–graphene nanocomposite by using 300 keV helium-ion irradiation at 823 K. Results showed that the intrinsic crystalline structure of graphene would be continuously disrupted by the elevated temperature and irradiation. However, lesser crystal defects, such as lattice swelling and stacking faults, and smaller helium bubbles are observed in the composite than those in its pure counterpart. The reason may be attributed to graphene's own capability in maintaining two-dimensional structure and inhibiting the formation of large-size defects. Thus, nickel–graphene interfaces can be maintained and their role in healing radiation-induced defects is still able to play. Results of the study highlight the potential of metal–graphene nanocomposites for use as radiation tolerance materials.

Ultra-low pressure gravity-driven membrane (GDM) filtration has been proposed as a cost-efficiency alternative for the decentralized drinking water supply in terms of its simple operation and low energy consumptions, whereas its undesirable removals of dissolved organic compounds (DOC) and relatively low flux impede its widespread application. In order to improve its filtration performance, filter media (granular activated carbon (GAC), zeolite and bio-ceramsite) was directly coated on the membrane surface to engineer an integrated GDM system. The coating filter layer and bio-cake layer on the membrane surface could engineer a highly porous “multifunctional double layer” structure, which facilitated improvements of stabilized flux by 30%–120% relative to GDM control. Besides, coating filter media to GDM can efficiently combine the complementary performance between filter coat and GDM filtration, and thus the removals of CODMn were improved to 21%, 30% and 70% in bio-ceramsite, zeolite and GAC coated systems. Furthermore, the integrated GDM systems conferred much higher potentials in resisting the shock load of contaminants (e.g. organics, ammonia, iron and manganese) compared to GDM control. In addition, a low-aeration cleaning in presence of filter media scouring could efficiently improve the flux recovery from 35% to 50–94%, while the membrane integrity test indicated that such filter media scouring would not damage the membrane surface. Overall, these findings can hopefully spark improvements of both permeability and permeate quality in GDM filtration and bring relevant benefits to the applications of GDM technologies for decentralized drinking water supply.

Algal extracellular organic matter (EOM) released from Microcystis aeruginosa can cause severe membrane fouling during algae-laden water treatment. To solve this problem, three typical sulfate radical-based advanced oxidation processes (SR-AOPs), i.e., ferrous iron/peroxymonosulfate (Fe(II)/PMS), UV/PMS and UV/Fe(II)/PMS, were employed as membrane pretreatment strategies. Their performance on mitigating EOM fouling of a ceramic UF membrane was systematically investigated and compared in the present study. The results indicated that SR-AOPs pretreatments could promote the reduction of DOC and UV254, and the removal performance showed an apparent regularity of UV/Fe(II)/PMS > Fe(II)/PMS > UV/PMS. The pretreatments were very effective for decomposing high-MW biopolymers (>20,000 Da) into low-MW humic substances (1000–20,000 Da), thus reducing the accumulation of high-MW biopolymers on membrane surface. With respect to membrane fouling control, Fe(II)/PMS significantly mitigated both reversible and irreversible membrane fouling, whereas UV/PMS only reduced reversible fouling, and exhibited little effect on irreversible fouling. By contrast, UV/Fe(II)/PMS showed the best performance for fouling reduction due to the synergistic effect of UV and Fe(II) for PMS activation. The dominating fouling mechanism was governed by both pore blockage and cake filtration, likely due to the bimodal MW distribution of EOM, and SR-AOPs pretreatments delayed the transition from pore blockage to cake filtration. In addition, SR-AOPs prior to UF membrane were also very effective to improve the removal of micropollutants (i.e., ATZ, SMT and p-CNB). These results demonstrate the potential application of SR-AOPs as pretreatment for membrane fouling control during algae-laden water treatment.

The self-healing mechanism of radiation-induced defects in nickel–graphene nanocomposite is investigated by atomistic simulations. Compared with pure nickel, nickel–graphene nanocomposite has less defects remained in the bulk region after collision cascades, illustrating self-healing performance. Nickel–graphene interfaces (NGIs) serve as sinks for radiation-induced defects and preferentially trap interstitials over vacancies. Energetic and kinetic calculations reveal that the defect formation energy and diffusion barrier are reduced in the vicinity of NGIs, and the reduction are pronounced for interstitials. When NGIs are loaded with interstitials, their segregation ability on radiation-induced defects improves significantly, and the radiation-induced defects near the NGIs diffuse more easily. Especially, the vacancies (or interstitials) near the NGIs tend to annihilate (or aggregate) with the interstitials trapped at the NGIs, which only happens at the interstitial-loaded side of NGIs. Therefore, nickel–graphene nanocomposite exhibits excellent radiation tolerance and shows promise as a structural material for advanced nuclear reactors due to its NGIs with the energetic and kinetic driving forces acting on radiation-induced defects.

Gravity-driven membrane (GDM) filtration is a promising technology for decentralized drinking water treatment due to its low energy requirements and simple operation. The reduced flux observed in GDM systems relative to other membrane treatment techniques remains a vital obstacle to their wider application. With the goal of further improving membrane flux and permeate quality, three simple and practical technologies have been examined as pre-treatments for GDM systems, (i) slow filtration with granular activated carbon (GAC), expected to remove both biodegradable and non-biodegradable contaminants, (ii) slow filtration with modified fiber ball (MFB), expected to promote biodegradation of organic compounds and (iii) microfiltration (MF), expected to reject suspended substances and particles. Results indicated that stable permeability increased by approximately 230%, 150% and 100% in GDM systems employing GAC, MFB and MF pre-treatments compared to the control. The dissolved organic compounds (DOC) were removed by approximately 60% and 30% in GAC/GDM and MFB/GDM, while MF/GDM and GDM control were not effective at DOC removal. Correlations between the stable flux and extracellular polymeric substances (EPS) concentration (R2 > 0.9) indicated that reduction of EPS should be responsible for the flux improvements. Tracing the fate of florescent foulants illustrated that the EPS was mainly secreted/converted by the microbes colonizing within the bio-fouling layer of the GDM system. During long-term filtration, assimilable organic compounds (AOC) which can serve as nutrients for the growth of microbes within the bio-fouling layer were efficiently consumed (>50%) by the biological pre-treatments. This reduction in AOC was linked with a reduction in the growth/activity of bacteria within the bio-fouling layer of GDM system and a reduction in EPS accumulation. Overall, biological pre-treatments can significantly enhance the flux and water quality produced by a GDM system without significantly increasing the operation and maintenance. These improvements in flux and water quality can hopefully spark wider adoption of GDM as an economical and environmentally-friendly technology for decentralized drinking water treatment.

The anaerobic digestion effluent (ADE) generated from biogas projects has raised increasing environmental concerns. In this study, the algal cells integrity, pollutants degradation and the community compositions shifts were evaluated during the ADE treatment with simultaneous biodiesel accumulation in photobioreactors (PBR). The operation of six PBRs was initiated with diluted ADE (625, 393, 272, 193, 178 and 167 mg/L SCOD). The results showed that the high concentration of ADE (625 mg/L SCOD) led to considerable inhibition of algal cells growth. By comparison, the PBR (272 mg/L SCOD) attained the maximum lipid productivity (59.13 mg/L·d), and complete nutrient (nitrogen and phosphorus) removal was observed in PBR (167 mg/L SCOD). Moreover, the highest viable algal cells (86.2%) was attained in PBR (272 mg/L SCOD). Therefore, this study provides a feasible technology for microalgal cultivation with simultaneous treatment of ADE in PBRs. In addition, the approach of excitation-emission matrices with parallel factor (EEMs-PARAFAC) was utilized to further understand the organics degradation. The removals of component 1 (humic-like) and component 2 (protein-like, biological production) were ascended by the increased algal and bacteria activity in the microalgal-bacterial consortium. Additionally, the community composition analysis illustrated that bacterial diversity was reduced by the inoculation with microalgae, which was attributed to the formation of stable function groups with satisfactory contaminant degradation abilities and good algal cell growth; and Chlorella species were dominant, which benefited biodiesel accumulation in PBRs. These findings demonstrated the potential of using a bacterial-microalgal consortium for ADE purification simultaneous biodiesel production.

Nickel–graphene (N–G) composites are potential candidate structural materials for molten salt reactors. A rapid preparation method for these composites by jet electrodeposition was developed, and the microstructure, microhardness, and corrosion properties of these composites were studied to explore the key parameters of the jet electrodeposition. Results indicated that the distribution of graphene in composites mainly depended on the concentration of graphene oxide (GO) in the plating solution. Composites deposited with GO concentration of 0, 0.5, 1 g/L showed surface root-mean-square roughness value (Rq) of 6, 12, and 28 nm, respectively. Meanwhile with the increase of GO concentration, the Hardness value became larger. The corrosion potential Ecorr and current Icorr of composites obtained at 0.5 g/L with the best surface quality were 193 mV and 5.7 × 10−6 A/cm2, respectively, which indicated the best electrochemical corrosion resistance. Hydrogen annealing can help self–repair of graphene microstructure.

The micro radioisotope thermoelectric generator can be invoked as a long-life power supply in low-power device applications. Improving the current, voltage and power of power sensors by enhancing the properties of thermoelectric material composites matters in low-power device applications. The micro radioisotope thermoelectric generator driven by the temperature difference between radial thermoelectric legs printed on polyimide substrate and the loaded central heat source is reported in this study. The electrical conductivity of n-type Bi2Te2.7Se0.3, p-type Bi0.5Sb1.5Te3, and p-type Sb2Te3 radial thermoelectric legs are 24.57–165.8 S·cm−1, with Seebeck coefficients of −176.6, 223.3 and 139.7 µV·K−1 respectively. Thermoelectric legs are prepared by screen printing with a paste consisting of epoxy resin and BiTe-based powders. The generator has five couples of radial thermoelectric legs, and their material properties are optimized through selecting the preliminary curing temperature. The electrical conductivity of n-type Bi2Te2.7Se0.3, p-type Bi0.5Sb1.5Te3, and p-type Sb2Te3 thermoelectric legs are 24.57–165.8 S·cm−1, with Seebeck coefficients of −176.6, 223.3 and 139.7 µV·K−1 respectively. When loaded with 1.5 W isotope heat sources, the prototype generator would generate an open-circuit voltage of 68.41 mV, a short-circuit current of 329.0 µA, and an output power of 5.81 µW at 39.20 mV. Stacking and series-parallel can harvest considerable energy.

This work designed and measured a remote sprayed fast-curing γ-radiation-shielding material that is used to encapsulate and collect radioactive wastes from places far away from high radiation areas in case of radioactive waste leakage accidents. The influence of the chemical composition design on curing time, shielding performance, thermal stability and mechanical performance of the γ-radiation-shielding material is discussed. Results showed that with the addition of catalysts, the cream time of the γ-radiation-shielding material increased remarkably to allow it to be ejected, while the tack-free time of the solidified composite material decreased to guarantee good encapsulation of the radioactive wastes. Due to the denser microstructure, the γ-radiation-shielding material with bis(2-dimethylaminoethyl) ether and phosphorus flame retardant V-490 show better γ-radiation-shielding performance and mechanical properties than other products. When the shielding functional filler content reached 60%, the composite presented excellent comprehensive properties and a good application prospect.

Two kinds of four-layer nuclear batteries based on γ-ray, AlGaInP semiconductor PN junction, and ZnS:Cu fluorescent materials were prepared. One was a four-layer radio-voltaic nuclear battery (FRVB) with a volume of 1.00 cm3, and another is a four-layer dual-effect nuclear battery (FDEB) with a volume of 1.03 cm3. The output performance levels of the two batteries were tested with the irradiation of an X-ray tube. Results show that the output power of the nuclear battery in parallel is significantly greater than that in the series. However, the output power and power density of FDEB in parallel, which were 57.26 nW and 55.59 nW/cm3, respectively, both five times as high as those of FRVB in parallel. Each sub-cell of FDEB was connected in different ways according to actual requirements. Different output currents and voltages were obtained, whereas no difference was observed in output power. Moreover, the energy deposition of X-ray at each AlGaInP or ZnS:Cu layer in FDEB was simulated by using MCNP5. A small amount of energy deposition in the fluorescent layer significantly improved the electrical output performance of the nuclear battery. A multilayer dual-effect energy conversion mechanism improved the electrical output performance of the nuclear batteries.

This study describes some results concerning the hybrid process of ultraviolet/chlorine (UV/chlorine) as a pre-oxidation strategy prior to ultrafiltration for the treatment of natural organic matter (NOM)-contaminated surface water. Chlorine has been extensively used in water treatment since it can act as disinfectant or coagulant aid. In addition, the combination of UV and chlorine, compared to the other oxidants generally used in water treatment, offers a potentially effective and cheaper alternative for pre-oxidation process. Parallel tests with or without the application of chlorine were conducted to evaluate the effect of chlorine dosage on the increase of trans-membrane pressure under low dosage of UV irradiation. The results showed that UV/chlorine pre-oxidation achieved remarkable reduction of both total membrane fouling (49%) and reversible membrane fouling (59%) at 4 mg/L dose of chlorine as a result of the removal of both high molecular weight (MW) (1–20 kDa) humic substances and lower MW compounds. Hybrid process of UV/chlorine and UF membrane achieved significant removal of DOC (34%) and UV254 (49%) at chlorine dosage of 4 mg/L and a UV dosage of 180 mJ/cm2. Modeling fit results indicated that the NOM-related membrane fouling mitigation was probably attributed to the alleviation of intermediate pore blocking and standard pore blocking with intermediate pore blocking playing a more important role. Additionally, the UV/chlorine unit could have a bright prospect for engineering application as it performed better in cost control as pretreatment prior to UF membrane compared to other pre-oxidation processes.

A concentric thermoelectric filament structure used for radioisotope thermoelectric generator (RTG) is designed to satisfy low-power and high-voltage demands for aerospace microelectronic devices. The thermoelectric filament is proven to have a better output voltage than the traditional thermoelectric structure by using COMSOL. The unbreakable thermoelectric filament and corresponding devices are prepared by employing a simple and easy brush coating process. A single thermoelectric filament obtains an open-circuit voltage (Voc) of 6.0 mV and a maximum power output (Pmax) of 2.0 μW at 398.15 K hot surface temperature. An array of thermoelectric filaments is fabricated for the radioisotope heat source of planar heat surface, which obtains Voc of 83.5 mV and Pmax of 32.1 μW at the hot surface temperature of 398.15 K, thereby verifying the practicability of the concentric filament structure in devices. Another radial thermoelectric filament device is designed for the cylindrical heat source. This device exports 84.5 mV Voc and 42.5 μW Pmax at the hot surface temperature of 398.15 K. These thermoelectric devices could gain larger electrical performance in small space through further series connection and fabrication, which will be a commendable design scheme for the radioisotope thermoelectric generator.

A dual effect multi-level isotope battery based on γ radioisotope source was proposed. Two types of energy conversion mechanisms, namely, radio-voltaic (RV) and radio-photovoltaic (RPV) effects, was combined to convert the radiation energy of γ ray to electricity. The theoretical performance limit for the dual effect multi-level isotope battery irradiated by 60Co radioisotope source was calculated, and the characteristics of each conversion mechanism were analyzed by using MCNP5. The results revealed that the RPV effect produced more electrical output than the RV effect, but the contribution of each effect on the battery was significant. The output performance of the multi-level isotope battery was characterized under 60Co source at dose rates of 0.103 kGy/h and 0.68 kGy/h. The theoretical and experimental study investigated the feasibility of combining two kinds of energy conversion mechanisms to enhance the performance of nuclear batteries. The use of 60Co radioisotope sources with a large activity and conversion modules with additional levels could obtain a considerable output performance. Moreover, the thickness influence of the LYSO scintillator on the performance limit in the first-level conversion module was studied to optimize the structural parameters of the multi-level dual effect isotope battery. The thickness of scintillator strongly affects the energy deposition distribution of gamma rays in the multi-level conversion module, resulting in changes of the output generated by RV and RPV effects, which in turn affects the total output of the battery.

With a highly functional methyl vinyl silicone rubber (VMQ) matrix and filler materials of B4C, PbO, and benzophenone (BP) and through powder surface modification, silicone rubber mixing, and vulcanized molding, a flexible radiation shielding and resistant composite was prepared in the study. The dispersion property of the powder in the matrix filler was improved by powder surface modification. BP was added into the matrix to enhance the radiation resistance performance of the composites. After irradiation, the tensile strength, elongation, and tear strength of the composites decreased, while the Shore hardness of the composites and the crosslinking density of the VMQ matrix increased. Moreover, the composites with BP showed better mechanical properties and smaller crosslinking density than those without BP after irradiation. The initial degradation temperatures of the composites containing BP before and after irradiation were 323.6°C and 335.3°C, respectively. The transmission of neutrons for a 2-mm thick sample was only 0.12 for an Am–Be neutron source. The transmission of γ-rays with energies of 0.662, 1.173, and 1.332 MeV for 2-cm thick samples were 0.7, 0.782, and 0.795, respectively. Keywords: Flexible Composite, Neutron Shielding, Radiation Resistance, γ-ray Shielding

To reduce fine particulate matter emission from coal burning sources especially fossil fuel fired energy generation facility is critical to improve air quality. Attapulgite suspension was attempted to spray in a 6 kW fluidized bed facility and reduce fine particulate matter emission during coal combustion. The key parameters such as attapulgite mass, flowrate and spraying zone were investigated to determine the optimal and critical conditions that influence fine particulate matter emission. Exciting results indicate that both fine particle number and mass concentrations are largely decreased due to the physical/chemical absorption with the suitable mass ratio of 3 wt%. The spray of attapulgite suspension in both dense bed and dilute bed effectively mitigates fine particle emission based on the agglomeration and absorption. The most excellent result is achieved at a flowrate of 38 ml/min in dense bed with particle number reduction up to 93.5% in PM2.5 (fine particles is equal to/less than 2.5 μm), 93.6% in PM1.0 (fine particles is equal to/less than 1.0 μm) and 93.7% in PM0.1 (fine particles is equal to/less than 0.1 μm), respectively. The work highlights the potential of spraying attapulgite suspension as an effective process to reduce fine particle emission during coal combustion in fluidized bed system.

Traditional radionuclide identification algorithm based on peak detection cannot recognize radioactive material in a short time. This study proposes a rapid radionuclide identification algorithm based on the discrete cosine transform and error back propagation neural network. Detection rate and accurate radionuclide identification distance were used to evaluate the proposed method. Experimental results show that the extracted feature vector of the spectrum is not influenced by time, activity, and distance. The proposed algorithm obtained better results in a relatively authentic environment, and it has the ability to predict the isotopic compositions of the mixed spectrum. The proposed method has a better identification performance for the spectrum of radionuclide masked by shielding material except the gamma rays emitted by related radionuclide are significantly shielded. It is also particularly recommended for the fast radionuclide identification of spectroscopic radiation portal monitors, radioisotope identification devices, and other radiation monitoring instruments.

An integrated gravity-driven membrane (GDM) and granular activated carbon (GAC) filtration process was operated for 193 days to investigate the influence of integrated GAC on the flux stabilization, permeate quality, composition of the biofouling layer and eukaryotic community compared with a GDM control system. The results revealed that the presence of GAC resulted in a strongly increased stable flux (6 L m −2 h −1 , compared to 2 L m −2 h −1 in the GDM control). Furthermore, the GAC/GDM system exhibited a significant removal of dissolved organic compounds (DOC) (50–70%) due to the adsorption and biodegradation process. By contrast, the DOC in the permeate of the control was approximately 20–30% higher than in the raw water, which was attributed to the hydrolysis of high-MW compounds. Furthermore, the composition of the biofouling layer attached on the membrane surface was significantly influenced by the presence of GAC, leading to a reduction of accumulated organic compounds by 60%. Likewise, the extracellular polymeric substances (EPS) were obviously reduced in the GAC/GDM system, especially the tightly bound EPS in the biofilm and EPS deposited in membrane pores. Additionally, the GAC could function as a eukaryotic pre-incubator, resulting in a higher diversity of the eukaryotic community and improving predation in the biofouling layer. Furthermore, a more porous, heterogeneous and permeable biofouling layer was observed in GAC/GDM. The higher flux in GAC/GDM system was attributed to (i) lower organic foulants (especially EPS) accumulated in the biofouling layer and membrane pores and (ii) highly heterogeneous structures due to improved activity of eukaryotes in the biofouling layer. These results are essential to develop robust maintenance-free, cost-effective and energy-efficient drinking water treatments.

The output properties of X-ray radioluminescence (RL) nuclear batteries with different phosphor layers were investigated by using low-energy X-ray. Results indicated that the values of electrical parameters increased as the X-ray energy increased, and the output power of nuclear battery with ZnS:Cu phosphor layer was greater than those of batteries with ZnS:Ag, (Zn,Cd)S:Cu or Y2O3:Eu phosphor layers under the same excitation conditions. To analyze the RL effects of the phosphor layers under X-ray excitation, we measured the RL spectra of the different phosphor layers. Their fluorescence emissions were absorbed by the GaAs device. In addition, considering luminescence utilization in batteries, we introduced an aluminum (Al) film between the X-ray emitter and phosphor layer. Al film is a high performance reflective material and can increase the fluorescence reaching the GaAs photovoltaic device. This approach significantly improved the output power of the battery.

Gravity-driven membrane filtration systems are promising for decentralized sewage treatment due to their low energy consumption and low maintenance. However, the low stable permeability/flux is currently limiting their wider application. With the ultimate goal of increasing permeability, the aim of this study was to evaluate the effect of coagulation (in situ coagulation and pre-coagulation) on the performance of a gravity-driven membrane bioreactor (GDMBR) during treatment of synthetic sewage. Results show that in situ coagulation significantly increased permeability (more than two-fold); however, no stabilization of permeability occurred over the whole operation, when non-coagulated and pre-coagulated reactors were compared. The high permeability observed was attributed to the accumulated aluminium floc in the reactor, which prevented formation of fluorescent microbial metabolites (aromatic and tryptophan proteins, as well as fulvic acids), and further avoided membrane pore blocking. In addition, the surface porosity of the fouling layer was improved (from 11.2% to 32.4% for non-coagulated and in situ coagulated reactors). The unstable permeability was possibly associated with lower biological processes within the fouling layer. These might include lower adenosine triphosphate (ATP) content and lower fluorescent metabolites from the extracellular polymeric substances (EPS) caused by the accumulated Al (compared with the control). On the other hand, pre-coagulation improved the level of stable permeability compared with the control (80 versus 40 L/m2 h bar), mainly because pre-coagulation decreased the EPS content and also maintained high ATP content of the fouling layer. In addition, both coagulation processes reduced the total filtration resistance, mainly the hydraulically reversible resistance and cake layer resistance, which could lower the cleaning frequency. Overall, coagulation could greatly increase the removal efficiency and improve the GDMBR permeability, which would make the process suitable for decentralized wastewater treatment.