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• Inhibition of Fibroblast-like synoviocytes-mediated synovial inflammation and synovial tissue hyperplasia may be a potential treatment for rheumatoid arthritis. • The analgesic and anti-inflammatory effects of Aconiti Lateralis Radix Praeparata are closely related to the existence of lipid-soluble alkaloids. • Aconiti Lateralis Radix Praeparata lipid-soluble alkaloids inhibited the expression and synthesis of inflammatory mediators and induced apoptosis. Fuzi lipid-soluble alkaloids (FLA) is the main bioactive components extracted from the traditional Chinese medicine Aconiti Lateralis Radix Praeparata ("Fuzi" in Chinese), which has promising analgesic and anti-inflammatory effects. However, the effects and the underlying mechanisms of FLA on rheumatoid arthritis (RA) have not been studied. The present study aimed to explore the anti-arthritic effects of FLA and its underlying mechanisms. To standardize the FLA, UPLC-HR-MS was used for quantitative and qualitative analysis of the representative alkaloids. Cell viability was measured by MTT. The anti-inflammatory activity of FLA was examined by analyzing the expression levels of inflammatory mediators such as TNF-α, IL-6, MMP-1, MMP-3, PGE2, and COX-2 using ELISA and RT-PCR analysis. The Annexin V-FITC/PI double staining method was used to detect the apoptosis of HFLS-RA and analyzed by flow cytometry. Western blot analysis was used to analyze the expression of NF-κB, MAPKs and mitochondrial apoptosis pathway related proteins. FLA had a significant inhibitory effect on the proliferation of HFLS-RA induced by IL-1β, which was accompanied by decreased expression levels of TNF-α, IL-6, MMP-1, MMP-3, COX-2 and PGE2. Remarkably, FLA inhibited the activation of NF-κB and MAPKs signaling pathways in IL-1β-induced HFLS-RA, as well as inducing HFLS-RA apoptosis through the mitochondrial apoptosis pathway. FLA inhibited the expression and synthesis of inflammatory mediators by inhibiting the activation of NF-κB and MAPKs signaling pathways in HFLS-RA, and induced apoptosis of HFLS-RA via the mitochondrial apoptosis pathway. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an experimental set-up dedicated to non-destructively test a 15cm-long Pressurized Water Reactor (PWR) nuclear fuel rod by neutron radiography (NR) is described. It consists of three parts: transport container, imaging block and steel support. The design of the transport container was optimized with Monte-Carlo Simulation by the MCNP code. The material for the shell of the transport container was chosen to be lead with the thickness of 13cm. Also, the mechanical devices were designed to control fuel rod movement inside the container. The imaging block was designed as the exposure platform, with three openings for the neutron beam, neutron converter foil, and specimen. Development and application of this experimental set-up will help gain much experience for investigating the actual irradiated fuel rod by neutron radiography at CARR in the future. [Copyright &y& Elsevier]

Abstract: In this contribution we present a system of converter (H3 10BO3) and phosphor (ZnS:Ag) which were fabricated by spraying method. The particle sizes and the mass ratio of the neutron converter and phosphor materials were optimized by simulation and experimental methods, respectively. Furthermore, the spatial resolution of scintillators at thicknesses of 0.40nm and 0.35mm were1.11 lp/mm (MTF=0.1) and 1.33 lp/mm (MTF=0.1), respectively. The results indicated that H3 10BO3/ZnS(Ag) scintillator have potential application in thermal neutron radiography. [Copyright &y& Elsevier]

Abstract: The radiography imaging with cold neutrons is being planned at China Advanced Research Reactor (CARR). The 60MW CARR at China Institute of Atomic Energy (CIAE) has got full power in March, 2012. It is a tank-in-pool type reactor using a D2O reflector for inverse neutron trap, and the expected optimal undisturbed thermal neutron flux is 8×1014 n/cm2 eutron imaging facility will be built at the guide hall. At present, its conceptional and physical designs have been finished. The cold neutron imaging facilities will provide an efficient and versatile tool for basic scientific and industrial non-destructive investigation. [Copyright &y& Elsevier]

Abstract: A real-time detector system for neutron radiography based on CMOS camera has been designed for the thermal neutron imaging facility under construction at China Advanced Research Reactor (CARR). This system is equipped with a new scientific CMOS camera with 5.5 million pixels and speed up to 100 fps at full frame. The readout noise is below 2.4 e/pixel. It is capable of providing images with much higher resolution and sensitivity at high frame rate. With optimized optical design and custom-built lens, the capture of quantitative information may be greatly enhanced. The maximum photon received by detector is calculated to be 2.1×103/pixel, while the camera resolution is 0.2mm at 30 fps according to the expected flux (5×107 n/cm2/s) at the sample position. [Copyright &y& Elsevier]

Abstract: A hybrid method, combining the radiative transfer theory and the method of moments (MoM), is proposed to study the potential effect of the lunar surface roughness on the microwave brightness temperature. The total upward emission reaching the lunar surface from below media is calculated by the radiative transfer theory, and then the brightness temperature is obtained by weighting the bidirectional transmission coefficients which is computed using the MoM. The method is validated by both flat and rough surface models with analytic solutions. With the hybrid method, brightness temperatures from simulated lunar model are calculated and compared to those from a flat layered model. The comparisons show that the effect of rough surface on brightness temperature cannot be ignored and also depends on many other factors, such as observation angle and polarizations. For vertical polarization, an optimal observation angle may exist to reduce the effect of surface roughness. These results indicate that the knowledge of lunar surface roughness is important in microwave remote sensing to the Moon and may probably provide a guide to lunar projects in future. [Copyright &y& Elsevier]

The power conversion efficiency of modern perovskite solar cells has surpassed that of commercial photovoltaic technology, showing great potential for commercial applications. However, the current high-performance perovskite solar cells all contain toxic lead elements, blocking their progress toward industrialization. Lead-free tin-based perovskite solar cells have attracted tremendous research interest, and more than 14% power conversion efficiency has been achieved. In tin-based perovskite, Sn2+ is easily oxidized to Sn4+ in air. During this process, two additional electrons are introduced to form a heavy p-type doping perovskite layer, necessitating the production of hole transport materials different from that of lead-based perovskite devices or organic solar cells. In this review, for the first time, we summarize the hole transport materials used in the development of tin-based perovskite solar cells, describe the impact of different hole transport materials on the performance of tin-based perovskite solar cell devices, and summarize the recent progress of hole transport materials. Lastly, the development direction of lead-free tin-based perovskite devices in terms of hole transport materials is discussed based on their current development status. This comprehensive review contributes to the development of efficient, stable, and environmentally friendly tin-based perovskite devices and provides guidance for the hole transport layer material design. [ABSTRACT FROM AUTHOR]

• The effect of temperature on spontaneous imbibition in sandstone was studied. • The spontaneous imbibition process was monitored by neutron radiography. • A spontaneous imbibition dynamics model including temperature was presented. • The effect of temperature on Imbibition parameters was quantitatively analyzed. To elucidate the imbibition behavior of water in complex temperature and stress environments, spontaneous imbibition experiments were conducted on unsaturated matrix sandstones at different vertical temperature gradients by neutron radiography technology. Additionally, corresponding dynamic models of water imbibition in porous media were established. The research results reveal the phased characteristics of sandstone spontaneous imbibition and the influence of vertical temperature gradient on the evolution of wetting front. Specifically, the initial development speed of the wetting front increases with an increase in the vertical temperature gradient, indicating a direct relationship. However, the growth rate of the wetting front gradually slows down with increasing time, eventually reaching a saturated state. Model validation demonstrates that the traditional Washburn's law is still valid in isothermal conditions without temperature gradient (G=0). Further analysis indicates that the imbibition rate has a direct correlation with linear thermal expansion coefficient (α) and viscosity temperature coefficient (β) across various vertical temperature gradients, and an inverse correlation with surface tension temperature coefficient (γ). Furthermore, when the values of α, β, and γ fall below 0.001, their impact on the imbibition rate becomes negligible. The sensitivity of the imbibition rate to parameters γ, β, and α decreases in that order, with γ being the most sensitive, followed by β, and α being the least sensitive. Moreover, the relative importance of α, β, and γ dictates their specific influence on the imbibition rate, and a synergistic effect exists among these parameters, which collectively influence the water absorption behavior of sandstone. [ABSTRACT FROM AUTHOR]

C14H12F2O5, monoclinic, P21/n (no. 14), a = 6.8723(2) Å, b = 27.0231(7) Å, c = 7.3669(2) Å, β = 109.235(3)°, Z = 4, V = 1291.75(7) Å3, Rgt(F) = 0.0484, wRref(F2) = 0.1335, T = 100 K. [ABSTRACT FROM AUTHOR]

C14H12F2O5, monoclinic, P21/n (no. 14), a = 6.8723(2) Å, b = 27.0231(7) Å, c = 7.3669(2) Å, β = 109.235(3)°, Z = 4, V = 1291.75(7) Å3, Rgt(F) = 0.0484, wRref(F2) = 0.1335, T = 100 K. [ABSTRACT FROM AUTHOR]

• This paper characterizes the compensation plan based on the optimal performance based bonu s for alignment by incorporating time inconsistent preferences. • For the flow payoff case, the presence of time inconsistent preferences enhances the fraction of the cash flows the manager should receive and delays investment. • For the lump sum payoff case, the smaller the time inconsistency, the higher the value sharing bonus needed for aligning interests with the managers and the earlier the investment. • The parameters describing the project v alue matter for the optimal contract scheme. This paper characterizes the optimal performance-based compensation plan for alignment by incorporating time inconsistent preferences. When investment payoffs are given in flow terms, the presence of time-inconsistency enhances the fraction of the cash flows the manager should receive and delays investment. However, in the lump-sum payoff case, the smaller the time inconsistency, the higher the value-sharing bonus needed for aligning interests with the managers and the earlier the investment exercise. Furthermore, we find that the parameters describing the project value also matter for the optimal contract scheme. [ABSTRACT FROM AUTHOR]

Aiming at the difficulty to extraxt the fault feature frequencies from vibration signal of wind turbine transmission, a new fault feature extraction and denoising method based on the Dual Tree Complex Wavelet Transform (DT-CWT) and the Singular Value Decomposition (SVD) is proposed. Because of the non-stationarity and modulation characteristics of fault signals, the original vibration signal is decomposed into several different frequency band components by Dual Tree Complex Wavelet Transform. Then for the layered signal containing fault characteristic frequency, Hankel Matrix is constructed and decomposed by using the SVD to eliminate noise and reconstruct the signal. Finally, the fault characteristic frequency is identified accurately by the Hilbert Envelope Spectrum. Both the experimental and simulation shows that this method is effective for wind turbine transmission fault feature extraction. [ABSTRACT FROM AUTHOR]

Highlights • UMAAEE is an effective method in the extraction of cherry seed oil. • UMAAEE is optimized by Plackett-Burman design and Box-Behnken design. • Oil by UMAAEE shows similar fatty acid compositions as compared with oil by SE. • Oil by UMAAEE exhibits superior quality as compared with oil by SE. • SEM shows that UMAAEE prompts the release of oil by destroying the cell structure. Abstract In order to increase the utilization of cherry seeds, ultrasonic-microwave assisted aqueous enzymatic extraction (UMAAEE) was used to extract cherry seed oil. Parameters of UMAAEE were optimized by Plackett-Burman design followed by Box-Behnken design. The oil recovery of 83.85 ± 0.78% was obtained under optimum extraction conditions of a 2.7% concentration of enzyme cocktail comprising cellulase, hemicellulase and pectinase (1/1/1, w/w/w), ultrasonic power of 560 W, microwave power of 323 W, extraction time of 38 min, extraction temperature of 40 °C, enzymolysis temperature of 40 °C, pH of 3.5, liquid to solid ratio of 12 mL/g, enzymolysis time of 240 min and particle size less than 0.425 mm. There were no significant differences in the fatty acid compositions of cheery seed oil by UMAAEE and Soxhlet extraction, and oil by UMAAEE possessed superior physicochemical properties and higher content of bioactive constituents. Scanning electron microscopy illustrated that enzyme hydrolysis and ultrasonic-microwave treatment causing the structural degradation of cherry seed was the main driving force for extraction. In this study, all results suggest that UMAAEE is an effective method to extract cherry seed oil. [ABSTRACT FROM AUTHOR]

A method was set up to prepare reference sources for calibration of surface contamination monitors using Nafion HP membrane to fix the radioactive nuclides on aluminium backing material. By investigating the adsorption mechanism including kinetics and pH, it has been proved the 241Am could be fixed on the membrane effectively. The surface emission rate and the activity was measured to characterize the sources. In addition, the uniformity of the sources was evaluated according to ISO 8769 and the standard deviation of the surface emission rates from each individual portion of the whole source was no greater than 5%. [ABSTRACT FROM AUTHOR]

Accurate measurement of low-level thoron gas and high-accuracy calibration of thoron measurement devices are essential for assessing and preventing thoron radiological risks. This study aimed to develop a thoron gas measurement technique using an airflow-through scintillation cell for both low-level measurement and high-accuracy calibration. To achieve this, a compartment model was developed to estimate the influence of progeny deposition and accumulation on the wall of the scintillation cell to prevent an overestimation of thoron. A self-developed scintillation cell was utilised to implement and validate this technique. The lower detection limit and measurement uncertainty were then evaluated to assess the feasibility of the technique for low-level measurement and high-accuracy calibration. The results showed that the compartment model effectively addressed the influence of progeny deposition. The measurement technique achieved a lower detection limit below 100 Bq m−3 even with the coexistence of that of 100 Bq m−3 of radon and attained a measurement uncertainty (k = 2) below 10% when the concentration of thoron exceeded 1000 Bq m−3. In summary, this study developed a reliable and practical thoron gas measurement technique using an airflow-through scintillation cell with a consideration of progeny deposition, and is expected to contribute to the assessment and prevention of thoron radiological risk. [ABSTRACT FROM AUTHOR]

Online burnup measurement of a single irradiated spherical fuel element using gamma spectrometry has been applied for years on HTR-10. This reactor has a complex operation history for varies experiments, which raises the uncertainty over the non-destructive measured burnup. In this research, three irradiated spherical fuel elements with different burnup were deconsolidated, and their coated particles were analysed by both radiometric methods based on Cs-137 activity and mass spectrometric methods based on neodymium and actinide mass. The burnup distribution in each spherical fuel element was indicated by fractional U-235 burnup of particles from various radii and relatively uniform. The inventory of Cs-137 in one spherical fuel element was measured by on- and off-line gamma spectrometry and results showed tiny differences. Destructively measured Cs-137 activities from particles indicate negligible portion of Cs-137 in the graphite matrix. Burnup calculated from Cs-137 by radiometric method and Nd-148 by mass spectrometric method were compared. Results showed that the two values were not significantly different for fuels with a clear radiation history, but differences were observed in the fuel with a complex radiation history. • The burnup of irradiated HTR-10 fuel was analysed using gamma and mass spectrometry. • The burnup distribution in irradiated HTR-10 fuel was generally uniform. • Burnup of the complex radiation history spherical fuel element was re-evaluated by neodymium. [ABSTRACT FROM AUTHOR]

Background: Thyroid-associated ophthalmopathy (TAO) is an autoimmune disorder. It has discriminable appearance. This study was conducted to dig the clinical significance of demographic characteristics and ophthalmologic diagram features in TAO diagnosis and stage/severity evaluation. Results: We included 320 males and 633 females, with an average age of 41.75 ± 13.75. A majority of TAO patients had hyperthyroidism, and most of them were in the inactive stage and at the moderate level. The thyroid function type, stage and severity were closely associated with hypopsia, eyelid congestion, conjunctival congestion, corneal ulcer, ocular motility disorder, best corrected visual acuity, and extraocular muscle thickening. Using these features, we established different logistic regression models to predict thyroid function subtypes, abnormal thyroid function, stage, and severity, in which the AUC of the ROC curve and accuracies were satisfactory. Conclusion: Together, TAO subtype, stage and severity can be diagnosed by auxiliary references including demographic factors, symptoms from complains, and image features. These non-invasive indices can be applied in a timely manner in clinical estimating TAO status. [ABSTRACT FROM AUTHOR]

The dynamic recrystallization (DRX) behavior of the extruded AZ80A magnesium alloy during plastic deformation was studied by coupling the physical-based finite element (FE) method and the developed cellular automata (CA) model. Isothermal compression tests were conducted by Gleeble-3800 thermal simulator at different temperatures of 598 K, 623 K, 648 K, 673 K, 698 K, and 723 K, and different strain rates of 0.001 s−1, 0.01 s−1, 0.1 s−1, and 1 s−1 to obtain the corresponding flow stress–strain curves. The constitutive model was established based on the analysis of the flow stress–strain curves. Moreover, parameters of the CA model were found. Based on the CA model, the DRX model was built. The established constitutive model and the DRX model were embedded in DEFORM-3D software to simulate the grain evolution under various deformation conditions. This combined method was capable of predicting the evolution of flow stress, DRX volume fraction, and DRX grain size in various deformation conditions. The results show that the error between the recrystallization volume fraction predicted by the finite element simulation and the CA model and the experimental results is less than 12.0%, and the error between the peak stress predicted by the CA model and the measured value remains within 8.0%. The prediction results of the combined methodology of the CA model and the FE simulation are consistent with the experimental results, which verify the usefulness and the prediction prospect of the coupled method. This method was probably a feasible choice to predict the DRX grain refinement of the thermal deformation process of the extruded AZ80A magnesium alloy. The dynamic recrystallization (DRX) behavior of the extruded AZ80A magnesium alloy during plastic deformation was studied by coupling the physical-based finite element (FE) method and the developed cellular automata (CA) model. The results show that the error between the recrystallization volume fraction predicted by the finite element simulation and the CA model and the experimental results is less than 12.0%, and the error between the peak stress predicted by the CA model and the measured value remains within 8.0%. [ABSTRACT FROM AUTHOR]

Summary: Osteoporosis has a high incidence and a low detection rate. If it is not detected in time, it will cause osteoporotic fracture and other serious consequences. This study showed that the attenuation values of vertebrae on chest CT could be used for opportunistic screening of osteoporosis. This will be beneficial to improve the detection rate of osteoporosis and reduce the incidence of adverse events caused by osteoporosis. Introduction: To explore the value of the attenuation values of all thoracic vertebrae and the first lumbar vertebra measured by artificial intelligence on non-enhanced chest CT to do osteoporosis screening. Methods: On base of images of chest CT, using artificial intelligence (AI) to measure the attenuation values (HU) of all thoracic and the first vertebrae of patients who underwent CT examination for lung cancer screening and dual-energy X-ray absorptiometry (DXA) examination during the same period. The patients were divided into three groups: normal group, osteopenia group, and osteoporosis group according to the results of DXA. Clinical baseline data and attenuation values were compared among the three groups. The correlation between attenuation values and BMD values was analyzed, and the predictive ability and diagnostic efficacy of attenuation values of thoracic and first lumbar vertebrae on osteopenia or osteoporosis risk were further evaluated. Results: CT values of each thoracic vertebrae and the first lumbar vertebrae decreased with age, especially in menopausal women and presented high predictive ability and diagnostic efficacy for osteopenia or osteoporosis. After clinical data correction, with every 10 HU increase of CT values, the risk of osteopenia or osteoporosis decreased by 32 ~ 44% and 61 ~ 80%, respectively. And the combined diagnostic efficacy of all thoracic vertebrae was higher than that of a single vertebra. The AUC of recognizing osteopenia or osteoporosis from normal group was 0.831and 0.972, respectively. Conclusions: The routine chest CT with AI is of great value in opportunistic screening for osteopenia or osteoporosis, which can quickly screen the population at high risk of osteoporosis without increasing radiation dose, thus reducing the incidence of osteoporotic fracture. [ABSTRACT FROM AUTHOR]

To separate thorium and uranium in nitric acid solution using anion exchange process, a strong base silica-based anion exchange resin (SiPyR-N4) was synthesized. Batch experiments were conducted and the separation factor of thorium and uranium in 9 M nitric acid was about 10. Ion exchange chromatography was applied to separate thorium and uranium in different ratios. Uranium could be eluted by 9 M nitric acid and thorium was eluted by 0.1 M nitric acid. It was proved that thorium and uranium can be separated and recovered successfully by this method. [ABSTRACT FROM AUTHOR]

[Display omitted] • A miniaturized step-added T-type photoacoustic cell was design with a compact volume of 1.16 cm3. • Stability assessments using Computational Fluid Dynamics revealed minimal impact of gas flow on system performance, ensuring reliable hydrogen detection. • An innovative photoacoustic frequency shift technique was introduced, capable of detecting hydrogen with a high linear correlation (R2 = 0.99825) and achieving a distinct frequency shift of 45 Hz per 1 % change in hydrogen concentration. In this study, we introduce an innovative photoacoustic frequency shift (PAFS) technique for hydrogen (H 2) detection, complemented by both theoretical models and practical experiments. To mitigate cross-sensitivity, we analyzed the sound speeds of six different gases, confirming minimal interference with H 2 due to significant velocity disparities. Central to our approach is the design of a miniaturized step-added T-type Photoacoustic Cell (PAC), with parameters meticulously optimized for enhanced performance. Using COMSOL Multiphysics' Thermal Viscous Acoustics module, we conducted simulations to evaluate the quality factor and acoustic pressure, both crucial for the sensor's efficiency. Additionally, we assessed the system's stability, influenced by gas flow, through gas velocity distribution analyses using the Computational Fluid Dynamics module. Experimental investigations focused on the system's sensing performance, revealing a distinct frequency shift of ∼45 Hz for every 1 % change in H 2 concentration, with a high linear correlation (R2 = 0.99825). The system's response and recovery times were measured at 1.09 s and 1.25 s, respectively. Long-term stability, evaluated over 3000 s using Allan deviation, indicated a minimum detection limit (MDL) of 102.47 ppm at an integration time of 375 s. These findings validate the efficacy of the step-added T-type PAC in H 2 detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • PCA greatly improved SMX removal in Fe(III)/PMS process under truly pH conditions. • PCA-Fe(III)-OOSO 3 - was proposed as the primary reactive species for SMX removal. • The toxicity of SMX solution declined after treatment with PCA/Fe(III)/PMS process. • PCA/Fe(III)/PMS process had strong anti-interference ability to water matrix. • PCA/Fe(III)/PMS process exhibited high SMX removal efficiency in nature waters. Protocatechuic acid (PCA) has been extensively employed as reducing agent to improve the Fenton-like processes under acidic pH conditions by accelerating the Fe(II)/Fe(III) redox cycle. Nevertheless, the potential of PCA as chelating agent to enable Fenton-like processes for contaminant elimination under neutral pH conditions has been overlooked. In this study, experiments and DFT calculations demonstrate that PCA can improve the elimination of sulfonamide antibiotics in Fe(III)/peroxymonosulfate (PMS) process under truly neutral pH conditions by improving the catalytic reactivity of Fe(III) with PMS, resulting in a 23.74-fold increase in the pseudo-first order rate constant (k obs) of sulfamethoxazole (SMX) removal at pH 7.0. Meanwhile, the k obs of SMX removal in PCA/Fe(III)/PMS process was 10–60 times higher than that in various previously reported strategies-enhanced Fe(III)/PMS processes at pH 7.0. The Fe(III)-peroxo intermediate (PCA-Fe(III)-OOSO 3 -), rather than •OH, SO 4 •-, Fe(IV)/Fe(V) and 1O 2 , was identified as the primary reactive species responsible for SMX removal in PCA/Fe(III)/PMS process under neutral pH conditions. DFT results indicate that PCA increased the oxidation potential of Fe(III)-OOSO 3 -. Meanwhile, PCA/Fe(III)/PMS process exhibited promising applicability in natural waters with strong anti-interference capability even with 5 μM Fe(III). Additionally, five potential elimination pathways of SMX were proposed, and the toxicity of treated SMX solution decreased. This study investigated the overlooked but crucial role of PCA in Fe(III)/PMS process under neutral pH conditions, which may provide novel insights into the underlying mechanism of PCA-enhanced Fenton-like processes and provide viable options for the application of Fe-catalyzed PMS processes in neutral waters. [ABSTRACT FROM AUTHOR]

[Display omitted] • NCP enhanced diclofenac removal in Cu(II)/PMS process under neutral pH conditions. • NCP improved the redox potential and reactivity of Cu(II) by forming Cu(II)-(NCP) 2. • Cu(III)-(NCP) 2 complex was the primary reactive species for diclofenac degradation. • NCP/Cu(II)/PMS process had well anti-interference ability to natural water matrix. • NCP/Cu(II)/PMS process possessed well performances even with trace Cu(II) dosage. The application of the Cu-catalyzed peroxymonosulfate (PMS) in pratical is seriously restricted due to its weak anti-interference capability against the natural water matrix and the slow conversion of Cu(II) by PMS under conditions of neutral pH. In this study, neocuproine (NCP) was found to greatly improve the performance of diclofenac elimination in the Cu(II)-catalyzed PMS process across a broad pH range of 7.0–10.0. The pseudo -first-order rate constant of diclofenac abatement in the NCP/Cu(II)/PMS process was 56.0 times greater compared to that in the Cu(II)-catalyzed PMS process at pH 8.0, and superior to the previously-reported hydroxylamine and gallic acid-enhanced Cu(II)-catalyzed PMS processes. Cu(III)-(NCP) 2 , as opposed to radicals, served as the major reactive species accountable for diclofenac abatement. Cu(II)-(NCP) 2 having higher oxidation–reduction potential was firstly produced by the complexation of Cu(II) with NCP, Cu(I)-(NCP) 2 was then produced via the interaction of Cu(II)-(NCP) 2 with the deprotonated form of PMS (i.e., SO 5 2−), Cu(III)-(NCP) 2 was finally produced by the reaction between Cu(I)-(NCP) 2 and PMS. Three potential degradation pathways of diclofenac were inferred from the determined nine degradation intermediates. Significant reduction in the toxicity of reaction solutions was discovered following diclofenac removal. Furthermore, the NCP/Cu(II)/PMS process demonstrated high anti-interference performance to inorganic anions (NO 3 −, SO 4 2−, HCO 3 − and Cl−), humic acid and actual water. Overall, this research provided an efficient approach to enhance the abatement of contaminants in the Cu(II)-catalyzed PMS process under neutral pH environments and to boost its anti-interference capability, which was favorable for its potential utilization in water treatment. [ABSTRACT FROM AUTHOR]

Separation of complete TRISO-coated fuel particles from matrix graphite is challenging but important for the post-irradiation examination (PIE) of high-temperature gas-cooled reactor (HTGR) fuel elements. Electrochemical technology is considered one of the most promising and effective approaches in this regard. Herein, to explore the influence of HNO 3 concentration on galvanostatic deconsolidation, 4%–68% HNO 3 were taken as examples. The matrix graphite anodes gradually exfoliated to fragments in 34% HNO 3 , while expanding in other concentrations. The characterization results of deconsolidated fragments and galvanostatic curves identified the highest oxygen content was reached in 34% HNO 3 due to the combined effect of intercalation, hydrolysis and oxygen evolution. In higher HNO 3 concentrations like 68%, the intercalating agent predominates and therefore the intercalation and following hydrolysis reactions are the main causes of matrix graphite deconsolidation, with no oxygen evolution occurring. In contrast, in lower HNO 3 concentrations like 4%, the violent oxygen evolution reaction hinders the intercalation and hydrolysis reactions. In short, only the combined interaction of intercalation, hydrolysis and oxygen evolution can deconsolidate the bulk matrix graphite into a more homogeneous powder. This work will provide more insights into the electrochemical deconsolidation mechanism and process of both HTGR fuel elements and other graphite materials. Electrochemical deconsolidation of the matrix graphite in three concentrations of nitric acid and its corresponding reaction mechanism. [Display omitted] • Deconsolidation of matrix graphite depended on the concentration of HNO 3 electrolyte. • Hydrolysis of co-intercalated H 2 O are the main cause of exfoliation of matrix graphite. • Water electrolysis and intercalation of NO 3 − resulted in the expansion of matrix graphite. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO), a toxic pollutant usually formed from incomprehensive combustion especially at low temperature, has harmful effects on human health. Therefore, the catalytic oxidation of CO always receives widespread attention. Herein, we reported transition metal (Cu, Co, Ni, Fe) doped ε-MnO 2 as CO catalysts using a hydrothermal-deposition method. Physiochemical properties for CO oxidation were meticulously analyzed employing characterization techniques such as SEM, XRD, BET, XPS, EPR, CO-TPR. The doped ε-MnO 2 catalyst showed expanded BET surface area, increased oxygen vacancy defects, more active sites, enhanced adsorption, and faster electron transfer. Catalytic activity tests indicated that the ε-MnO 2 catalyst doped with transition metals exhibited exceptionally high catalytic activity, with the Cu-doped catalyst showing the fastest chemical reaction rate and the lowest complete conversion reaction temperature (TOF of 9.92 × 10−3 s−1, at 65℃). Density Functional Theory (DFT) calculations indicated that Cu doping more effectively induced oxygen vacancy defects compared to Co, Ni, Fe, and raw ε-MnO 2 catalysts. It identifies the CO oxidation reaction and improved the CO adsorption capacity of the catalyst. Furthermore, a novel potential reaction pathway for the M-vK mechanism in transition metal oxides was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • H 2 O 2 significantly improved NPX removal in the Cu(II)/PMS process in pH 9.0–11.0. • The Cu(II)/Cu(I) cycling was greatly accelerated with the addition of H 2 O 2. • Cu(III) was the predominant reactive species responsible for NPX degradation. • The addition of H 2 O 2 could suppress the production of halogenated by-products. • The proposed H 2 O 2 /Cu(II)/PMS system was well tolerant to real water matrix. The susceptibility to the natural water matrix and the risk-generating halogenated by-products in the Cu(II)/peroxymonosulfate system heavily restricted its practical application. This study first demonstrated hydrogen peroxide (H 2 O 2) could remarkably improve the anti-interference capacity of the Cu(II)/peroxymonosulfate system in the natural water matrix through promoting the copper species cycle [Cu(II)/Cu(I)]. A complete naproxen (NPX) removal was achieved at pH 10.0 for 180 s with the H 2 O 2 /Cu(II)/peroxymonosulfate system, and the degradation rate of NPX was 28 times greater than its counterpart without H 2 O 2 ·H 2 O 2 functioned as an electron donor to reduce Cu(II) to Cu(I), while the formed Cu(I) preferentially interacting with peroxymonosulfate to generate reactive species. Several reactive species, including Cu(III), •OH and SO 4 •−, participated in NPX degradation, while Cu(III) primarily contributed to NPX abatement. The NPX abatement in the H 2 O 2 /Cu(II)/peroxymonosulfate system was strongly pH-dependent, with weakly alkaline circumstances being more beneficial to its removal. Additionally, Cl−, H 2 PO 4 2− and humic acid in the natural water matrix had the slight impact on NPX elimination with the H 2 O 2 /Cu(II)/peroxymonosulfate system, whereas H 2 PO 4 2− and humic acid strongly suppressed NPX elimination in the Cu(II)/peroxymonosulfate system. Furthermore, the generation of halogenated by-products could be suppressed in treating halide-containing wastewater with the H 2 O 2 /Cu(II)/peroxymonosulfate system. To sum up, this research offered a new strategy to strengthen the anti-interference capacity of the Cu(II)/peroxymonosulfate system and simultaneously inhibiting halogenated by-product production. The finding should be important for studying the synergistic effect of dual oxidants in treating Cu(II)-containing wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glucose-derived microporous carbons with different and ratios was prepared. • GC-700-2.4 showed narrow pore size distribution with < 7 Å. • GC-700-2.4 showed high Kd of Radon for 9.51 L/g at ambient temperature. • GC-700-2.4 exhibited a potential application with the economic cost. Radon (Rn) is a radioactive noble gas and one of the primary culprits of lung cancer. Developing efficient adsorbents for Rn removal is of paramount importance, yet remains a daunting challenge due to the weak interaction between Rn and the adsorbent, particularly when low concentrations of Rn are present. Herein, a renewable biomass-derived carbon material consisting of rich ultramicropores was synthesized for record-high Rn adsorption under ambient condition. By meticulously selecting the carbonization precursor, chemical activator, and pyrolysis temperature, the optimized adsorbent, GC-700-2.4, exhibits a narrow pore distribution in the ultramicroporous range (<7 Å). The dynamic adsorption coefficient (K d) of GC-700-2.4 is determined to be 9.51 L/g based on radon breakthrough experiments, which is twice the value of the commercial Rn adsorbent, coconut shell activated carbon (K d = 4.65 L/g), and outperforms all other reported Rn adsorbents under comparable conditions. The superior Rn adsorption performance of GC-700-2.4 is attributed to the narrow ultramicropores in GC-700-2.4 that show enhanced confinement effect toward Rn. Consequently, GC-700-2.4 shows promising potential for practical applications as an efficient and cost-effective Rn adsorbent. [ABSTRACT FROM AUTHOR]

N,N,N′,N′-tetramethylmalonamide (TMMA) has been successfully grafted onto the chloroacetylated poly(styrene-co-divinylbenzene) resin to obtain a novel diamide-based resin (PS–TMMA). PS–TMMA exhibited high adsorption capacity and selectivity toward TcO4− in 0.1–1 M HCl. The adsorption process of PS–TMMA conforms (Revise: conformed) to Langmuir isotherm and pseudo-second-order kinetics model. The results of column experiments revealed TcO4− can be completely separated from the coexisting fission products (Sr(II), Eu(III), Dy(III), and 1 M NH3·H2O can re-collect TcO4− absorbed in the resin column. The adsorption mechanism of TcO4− is considered that PS–TMMA is converted into anion exchange resin in acidic condition. [ABSTRACT FROM AUTHOR]

As the largest carbon emitter, China has a heavy task to allocate responsibilities in all stakeholders of supply chain. Previous studies have underestimated the transmission-related responsibility for carbon emissions reduction along supply chain. This study aims to combine Structural Path Analysis (SPA) and transmission-based betweenness (TBB) model to trace the critical transmission paths and nodes from production origins to final demand destinations of China in 1997–2017. Results show that: (1) Emission-mitigating responsibilities vary greatly under three types of emission accounting methods. Energy-intensive sectors (i.e., PSE, NMM and MES) are the largest emitters for production-based emission (PBE), and CON and SER are main contributors with high consumption-based emission (CBE). While the sectors with high transmission-based emission (TBE) have usually been neglected and converged in manufacturing sectors, including WAP and EOE for consumption, TEX for investment, TEX and MEP for export. Transmissions of carbon emission among the critical sectors are strengthened. (2) Final demand structure is shifting from the consumption-oriented (1997–2002), export-oriented (2002–2007), investment-oriented (2007–2012) to the consumption-oriented (2012–2017). The responsible sectors to satisfy consumption, investment and export show great disparity, namely SER, CON and PSE respectively. Cleaner energy structure (i.e., decreasing coal-related emissions and increasing gas-related emissions) is attributed to PSE, MES, TRW and SER. (3) Some transmission paths (staring from production side to consumption side) with more emissions, including "PSE→consumption", "CON→NMM→investment" and "WHR→export" deserve more attention. This study provides implications for the greening of supply chain and allocation of emission-mitigating responsibilities fairly. • SPA and TBB models are used to trace transmission changes of emission in 1997–2017. • Transmission paths and nodes from the perspective of PBE, CBE and TBE are compared. • Key transmission paths include PSE.→consumption, CON→NMM→investment and TRW→export. • Manufacturing sectors are top transmission sectors, which are underestimated. • Key emitters for consumption-oriented demand and cleaner energy mix are identified. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ascorbic acid (AA) significantly enhanced the removal of DCF in Fe(III)/PAA process. • Fe(III)-AA complex was formed by AA and Fe(III) prior to the generation of Fe(II). • FeIVO2+ was identified as the primary reactive species on the degradation of DCF. • AA/Fe(III)/PAA process performed well tolerance in actual water samples. • AA/Fe(III)/PAA process exhibited high selectivity towards different micropollutants. To overcome the sluggish reduction from Fe(III) to Fe(II) and excessive iron sludge production in Fe(III)/peracetic acid (PAA) process, ascorbic acid (AA), an environmental-friendly and natural reductant, was proposed in this study to boost the oxidation ability of Fe(III)/PAA process by facilitating the cycling of Fe(III)/Fe(II). AA-enhanced Fe(III)/PAA process exhibited remarkable acceleration in the degradation of diclofenac (DCF), with the removal rate of DCF being around 51 times higher than that without AA. Multiple reactive species of FeIVO2+, R-O, and OH were involved in the abatement of DCF in the AA/Fe(III)/PAA process. FeIVO2+ was confirmed as the predominant contributor for the elimination of DCF, whereas R-O and OH also participated in DCF abatement. In the AA-enhanced Fe(III)/PAA process, AA rapidly complexed with Fe(III) to produce the Fe(III)-AA complex, which was subsequently decayed to generate Fe(II), and then reactive species were generated by activating PAA with Fe(II) to degrade DCF through the pathways of dichlorination-cyclization, decarboxylation, and hydroxylation. The acute toxicity of the reaction solution employing BioFixlumi as a toxicity indicator decreased with the abatement of DCF. Common inorganic ions, including Cl−, SO 4 2−, CO 3 2−, and NO 3 −, had no adverse influence on DCF degradation, while humic acid and common cations (Zn2+, Ca2+, and Mg2+) inhibited DCF abatement. AA/Fe(III)/PAA process was highly effective for DCF removal in actual water samples, including surface water and underground water. AA/Fe(III)/PAA process was prone to degrading micropollutants with higher fractions of deprotonated species and lower ionization potentials, and performed with high selectivity towards micropollutants. Overall, the outstanding oxidation capacity and environmental friendliness of AA/Fe(III)/PAA process render it a potential technology to remove micropollutants in wastewater treatment. [ABSTRACT FROM AUTHOR]

Abstract Saturation magnetization and ferromagnetic resonance linewidth are important parameters for microwave devices, such as circulator/isolator. Conventional sintering of ferrite ceramics is prevalently performed to promote the densification. Here, we present a new sintering approach for obtaining uniform and dense NiCuZn ferrite ceramics with enhanced gyromagnetic properties at low temperatures. The NiZn-series ferrites (Ni 0.2 Cu 0.2 Zn 0.6 Fe 2 O 3 – 1.0 wt% Bi 2 O 3 +0.5 wt% MnO 2) was synthesized by solid reaction routes with new sintering approaches. The results indicate that a one-transient-step sintering process (OTSP) can significantly improve the gyromagnetic properties at low sintering temperatures by suppressing the anomalous grain growth, such as higher saturation magnetization (4π M s = ∼3904 Gauss) and lower ferromagnetic resonance linewidth (ΔH = ∼170 Oe). Therefore, such a methodology is quite significant due to it provides a referential experience for effective sintering route that can enable broad practical applications, such as other ferrite ceramics. Highlights • Uniform and compact NiCuZn ferrites can be achieved by a novel method. • Suppressing grain growth enhanced the gyromagnetic properties of NiCuZn ferrites. • Transient sintering method was suitable for broadband microwave devices. [ABSTRACT FROM AUTHOR]

• The system is specifically designed for CH4 detection, addressing the unique challenges associated with CH4 molecules and their distinct relaxation characteristics compared to other gases. • A detailed mathematical model of the beat frequency is derived and presented in the manuscript, enhancing the understanding and analysis of the system's performance. • An innovative investigation of the relationship between the optimal wavelength scanning rate and frequency bias is conducted, providing valuable insights for the optimization of BF-QEPAS systems. Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) is a sensitive and selective analytical technique widely used for gas sensing. To improve the response time of the methane sensing system based on QEPAS, a Beat Frequency Quartz-Enhanced Photoacoustic Spectroscopy (BF-QEPAS) system was developed. Theoretical model based on the classical spring-mass oscillator model to explain the generation of beat-frequency signal in the quartz tuning fork (QTF) was established. The BF-QEPAS system parameters were optimized and evaluated using the developed system. The performance of the system was analyzed through Allan variance and gas calibration. Experimental results showed that the BF-QEPAS system achieved a minimum detectable limit of 28.35 ppm for methane with an integration time of 114 s. The corresponding minimum detectable normalized noise equivalent absorption (NNEA) coefficient was 1.93 × 10-9 cm-1WHz1/2, which demonstrates the excellent sensitivity of the BF-QEPAS system for methane detection. [ABSTRACT FROM AUTHOR]

Water flow in unsaturated tight sandstones plays a significant role in the area of the secondary and enhanced hydrocarbon recovery as well as the geological storage of carbon dioxide and nuclear wastes. Although a few non-destructive techniques, such as nuclear magnetic resonance, magnetic resonance imaging and X-ray imaging, can be used to capture fluid transport in sub-micron pores, great challenges exist due to the presence of iron or the use of the contrast agents (e.g. cesium chloride and salts), resulting in inaccurate results or alteration of the wetting behavior of the porous media. In addition, models for describing diffusivity and water transport in unsaturated tight sandstones are also limited. In this work, the neutron radiography facility at China Advanced Research Reactor was used to determine water content profiles during the water imbibition in two types of tight sandstones: silty sandstone and coarse grained sandstone. The diffusivity was determined separately by three methods, including Matano’s method, Meyer-Warwick method and a fractal method, which was introduced as probably the first attempt to relate the microstructure observed by the high resolution X-ray computed tomography (CT) with the unsaturated diffusivity function for the tested tight sandstones. The air-entry value and the fractal dimension used in the fractal model were calculated based on the results of mercury intrusion porosimetry and CT data, respectively. The results from neutron images illustrate that the fractal model can give a reasonable description of the diffusivity function for the tested sandstones. Meyer-Warwick model produces a little bit higher diffusivity value at low water content range. The fractal model works better for the silty sandstone. Results also show that the value of water diffusivity increases with the increase in volumetric water content for both tested tight sandstones. This work shows that neutron radiography offers a feasible and more reliable way for characterizing fluid flow in other tight geo-materials and the fractal model also provides an easier way to give a quantitative description of the diffusivity than the core-flooding or centrifuge drainage experiment. [ABSTRACT FROM AUTHOR]

A novel silica-based anion exchange resin (SAER) was prepared to treat the uranium-contaminated water. SAER was characterized by SEM, TG, FT-IR and BET. Batch experiments were conducted to investigate its potential in removing uranium. Experimental results suggested that SAER could efficiently eliminate uranium in water solution with pH ranging from 5 to 9, and showed an amazing exchange speed and large working capacity. However, SO , Ca and Mg showed some effects on the adsorption of uranium. It was observed that uranyl carbonate complexes could promote Ca and Mg to be adsorbed onto SAER. According to the batch results, Feasible adsorption mechanism to uranium was proposed. At last, tap water containing uranium was mixed with SAER to test its performance. Results showed that uranium was removed successfully with equilibrium pH below 7 but near neutral. [ABSTRACT FROM AUTHOR]

For separating americium from lanthanides, a macroporous silica-based polymeric adsorbent (HDEHP/SiO-P) was prepared in this study. Using this adsorbent, the adsorption characteristics of Am(III) and lanthanides were investigated in HNO solutions. The obtained results displayed that heavy lanthanides had greater adsorption towards HDEHP/SiO-P than Ce(III) and Am(III). The adsorption behavior of Am(III) was found to be similar with Ce(III) in 0.1-0.3 M HNO solutions. The adsorption kinetics of Gd(III) and Ce(III) reached equilibrium within 2 h and fitted well with the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]

A ratiometric fluorescence detection method for trace amount of uranyl ion (UO 2 2+ ) was developed in this study, based on aggregation induced emission enhancement (AIEE) characteristics of 3-hydroxyflavone salicylaldehyde azine (HFSA) and luminescent signal of UO 2 2+ -HFSA complex in soluble state. The fluorescent ratio ( I 457 / I 534 ) was linearly related to the concentration of UO 2 2+ in the range of 0.5–20 ppb (part per billion). Analytical data showed that a detection limit of 0.5 ppb was achieved with the relative standard deviation (R.S.D.) 1.3% ( n =5). The proposed method could also be utilized for imaging UO 2 2+ in living cells by ratiometric fluorescence changes. [ABSTRACT FROM AUTHOR]

In order to separate and pre-concentrate uranium from aqueous phase, a novel silica-based adsorbent was prepared by impregnating nalidixic acid (HNA) into a macroreticular silica/polymer composite support (SiO-P) with a mean diameter of 60 μm. Adsorption behavior of uranium from aqueous solution onto the adsorbent was studied. Experimental results indicated that HNA/SiO-P showed strong adsorption for uranium in a wide range of pH from 3.5 to 10.0, and the maximum adsorption capacity was 35.4 mg g. In addition, HNA/SiO-P exhibited good selectivity for U(VI) and showed weak or bare adsorption affinity to foreign ions. Kinetic and isotherm of uranium adsorption were in accordance with the pseudo-second-order kinetic model and Langmuir isotherm adsorption model, respectively. Moreover, U(VI) sorption was found to be an endothermic reaction and spontaneous under experimental state. The synthesized adsorbent showed an admirable stability at lower pH values in aqueous solution. [ABSTRACT FROM AUTHOR]

The human social and behavioral activities play significant roles in the spread of COVID-19. Social-distancing centered non-pharmaceutical interventions (NPIs) are the best strategies to curb the spread of COVID-19 prior to an effective pharmaceutical or vaccine solution. This study investigates various social-distancing measures' impact on the spread of COVID-19 using advanced global and novel local geospatial techniques. Social distancing measures are acquired through website analysis, document text analysis, and other big data extraction strategies. A spatial panel regression model and a newly proposed geographically weighted panel regression model are applied to investigate the global and local relationships between the spread of COVID-19 and the various social distancing measures. Results from the combined global and local analyses confirm the effectiveness of NPI strategies to curb the spread of COVID-19. While global level strategies allow a nation to implement social distancing measures immediately at the beginning to minimize the impact of the disease, local level strategies fine tune such measures based on different times and places to provide targeted implementation to balance conflicting demands during the pandemic. The local level analysis further suggests that implementing different NPI strategies in different locations might allow us to battle unknown global pandemic more efficiently. • The study investigates the effectiveness of nonpharmaceutical intervention strategies on curbing the spread of COVID-19. • We investigated from a global perspective (forest view) and a local (trees view) perspective with advanced spatial models. • The forest view is timely and effective for decision-making, the trees view supplies more details for efficient NPIs. • A combined global and local (forest and trees) research paradigm produces holistic views of geographical problems. [ABSTRACT FROM AUTHOR]

• The concentration of HNO 3 electrolyte determined the oxidation of matrix graphite. • Chemical composition of matrix graphite deconsolidation products was analyzed. • Carbonyl group of deconsolidation product plays a dominant role in Sr2+ adsorption. With the development of high-temperature gas-cooled reactor (HTGR), the disposal of its spent fuel elements will become an important factor that affects its industrialization. As one of alternative routes for head-end process of HTGR spent fuels' reprocessing, electrochemical deconsolidation method separates TRISO fuel particles from matrix graphite (MG) and produces electrochemical deconsolidation product (EDP) with larger surface area than MG and abundant functional groups. In this paper, the chemical composition and structure of EDPs obtained in HNO 3 with concentrations of 4%, 34% and 68% were studied, and the application of EDPs on strontium ions (Sr2+) adsorption was investigated. The results showed that EDP-4% with more carbonyl groups on the surface possessed the largest Sr2+ capacity of 44.8 mg/g at pH 5, while EDP-34% containing more hydroxyl and epoxy groups had the smallest capacity of 9.6 mg/g. The capacity for EDP-68% lay in the mid value of 19.5 mg/g. Density functional theory (DFT) calculations and adsorption experiments jointly evidenced that the type and amount of functional groups both significantly impacted the Sr2+ adsorption. The proposed adsorption mechanism provides theoretical foundation to evaluate the distribution of 90Sr during HTGR spent fuels' electrochemical deconsolidating. The chemical composition of the electrochemical deconsolidation products of matrix graphite and optimal adsorption sites for Sr. [Display omitted] [ABSTRACT FROM AUTHOR]

Neutron radiography has many advantages over X-ray in inspection of materials containing lighter elements, elements with close atomic numbers, isotopes, radioactive materials and so on, and plays an irreplaceable role in nondestructive testing, material engineering and other fields. However, for plate-like components which are widely used in engineering, traditional neutron computed tomography (CT) scanning, limited by neutron energy, cannot collect complete, high-sensitivity and high-spatial-resolution projection information required for accurate reconstruction, which makes it impossible to obtain ideal reconstruction images of plate-like components. Neutron computed laminography (CL), as a popular nondestructive testing technology, has unique advantages for detection of plate-like components. Aimed at neutron tomographic inspection of plate-like samples, a detachable CL scanning mechanism was designed, and a neutron CL scanning system was built. The FBP (Filtered Back-projection) algorithm, the BPF (Back-projection Filtration) algorithm and the iterative reconstruction algorithm based on the minimization of total variation of 3D reconstructed image were designed. The results showed that FBP algorithm and BPF algorithm are of high reconstruction efficiency and can meet the needs of tomographic imaging in engineering inspection. The iterative reconstruction algorithm based on total variation minimization has advantages of high imaging accuracy and anti-noise, and can effectively suppress the adherent artifacts between adjacent reconstructed slices. Tomographic imaging of typical plate-like components was performed at the China Advanced Research Reactor (CARR) of China Institute of Atomic Energy (CIAE), which verified practicability and correctness of the detachable CL scanning mechanism and the reconstruction algorithms. • A detachable CL scanning mechanism is designed and built. • A back-projection filtered reconstruction algorithm for neutron beam CL scanning is proposed. • A neutron CL scanning experiment is carried out, the plastic structures of plate-like samples are clearly represented. [ABSTRACT FROM AUTHOR]

Bi 0.9 Pr 0.1 FeO 3 (BPF), BiFe 0.9 Ti 0.1 O 3 (BFT), Bi 0.9 Pr 0.1 Fe 0.9 Ti 0.1 O 3 (BPFT-10), and Bi 0.9 Pr 0.1 Fe 0.95 Ti 0.05 O 3 (BPFT-5) ceramics are prepared for a comparison study. X-ray diffraction indicates that all of the samples crystallize in rhombohedral structures with R 3c symmetry. The Pr and Ti co-doped samples show an especially low dielectric loss of 0.02–0.04 throughout the entire investigated frequency range. A markedly improved polarization hysteresis loop is successfully achieved for samples BPFT-10 and BPFT-5, and their remnant polarization P r values are 0.11 and 0.29 μC/cm 2 , respectively. Magnetic measurements indicate that the substitution of Ti 4+ for Fe 3+ improves the ferromagnetic properties due to the suppression of the spiral spin structure. A remnant magnetization M r of 0.176 emu/g was observed for BPFT-10 at 5 K. [ABSTRACT FROM AUTHOR]

In order to predict OH and H radicals initiated degradation of proton exchange membrane (PEM) based on polymers obtained by radiation-induced grafting of styrene or α-methylstyrene on different polyolefin, isopropyl benzene sulfonic acid (IPBS) and tert-butyl benzene sulfonic acid (TBBS) were taken as model compounds for PEM with and without α-H, respectively. Results indicated that OH radicals played a vital role in PEM degradation. Eighty-nine percent of OH radicals reacted with IPBS to form benzylic radicals by electron transfer and subsequent deprotonation reactions. Benzylic radicals can react with O to form peroxyl radicals, which leads to PEM degradation. TBBS, without α-H, reacted with OH or H radicals, benzylic radicals would not be generated, and only adducts were formed. Adducts have less influence on the stability of TBBS than benzylic radicals. In this work, we elucidated that PEM, without α-H, with similar structures to TBBS, had a stronger resistance to oxidative degradation than PEM with α-H, with similar structures to IPBS. [ABSTRACT FROM AUTHOR]

It is widely believed that a neutron beam can be focused to a small spot using a parabolic guide, which will significantly improve the flux. However, researchers have also noted challenges for the neutron inhomogeneous phase space distribution in parabolic focusing guide systems. In this paper, the sources of most prominent optical aberrations, such as an inhomogeneous phase space distribution and irregular divergence distribution, are discussed, and an optimization solution is also proposed. We indicate that optimizing the parabolic guide geometrical configuration removes almost all of the aberrations and yields a considerable intensity gain factor. [ABSTRACT FROM AUTHOR]

A novel silica-based adsorbent Me-CA-BTP/SiO-P was prepared to separate minor actinides from fission products in high level liquid waste. Me-CA-BTP/SiO-P adsorption behavior towards Am(III) and main FP from HNO solutions were studied. The adsorbent exhibited much higher affinity for Am(III) over FP elements in a large HNO concentration range and possess good adaptability as HNO concentration changes. Dy(III), as a simulated element of MA(III), showed good adsorption properties and elution performance. Dy(III) adsorption kinetics and isotherm followed the pseudo-second-order rate law and Langmuir isotherm adsorption model, respectively. Adsorbed Dy(III) could be effectively eluted from Me-CA-BTP/SiO-P by HO or dilute HNO. [ABSTRACT FROM AUTHOR]