Application of Fault Diagnosis Method Combining Finite Element Method and Transfer Learning for Insufficient Turbine Rotor Fault Samples.

Deep learning has led to significant progress in the fault diagnosis of mechanical systems. These intelligent models often require large amounts of training data to ensure their generalization capabilities. However, the difficulty of obtaining turbine rotor fault data poses a new challenge for intelligent fault diagnosis. In this study, a turbine rotor fault diagnosis method based on the finite element method and transfer learning (FEMATL) is proposed, ensuring that the intelligent model can maintain high diagnostic accuracy in the case of insufficient samples. This method fully exploits the finite element method (FEM) and transfer learning (TL) for small-sample problems. First, FEM is used to generate data samples with fault information, and then the one-dimensional vibration displacement signal is transformed into a two-dimensional time-frequency diagram (TFD) by taking advantage of the deep learning model to recognize the image. Finally, a pre-trained ResNet18 network was used as the input to carry out transfer learning. The feature extraction layer of the network was trained on the ImageNet dataset and a fully connected layer was used to match the specific classification problems. The experimental results show that the method requires only a small amount of training data to achieve high diagnostic accuracy and significantly reduces the training time.

Electrocleavage Synthesis of Solution-Processed, Imine-Linked, and Crystalline Covalent Organic Framework Thin Films.

Developing a general, facile, and direct strategy for synthesizing thin films of covalent organic frameworks (COFs) is a major challenge in this field. Herein, we report an unprecedented electrocleavage synthesis strategy to produce imine-linked COF films directly on electrodes from electrolyte solutions at room temperature. This strategy enables the cathodic exfoliation of the COF powders to nanosheets by electrochemical reduction and protonation, followed by nanosheets migrating to the anode and reproducing the COF structures by anodic oxidation. Our method is adaptable with most imine-linked COFs by virtue of the low redox potential of the imine bonds, whereas the COF films possess high crystallinity and hierarchical porosity. We highlight these COF films as a superb platform for promoting mass transfer by demonstrating their extraordinarily rapid iodine adsorption with record-high rate constants.

N-Oxide Zwitterion Functionalized Positively Charged Polyamide Composite Membranes for Nanofiltration.

N-Oxide zwitterionic polyethyleneimine (ZPEI), a new kind of aqueous phase monomer synthesized by commercially branched polyethyleneimine (PEI) via oxidation reaction, was prepared for fabrication of thin-film composite (TFC) polyamide membranes via interfacial polymerization. The main factors, including the monomer concentration and immersion time of the aqueous phase and organic phase, were investigated. Compared with PEI-TFC membranes, the obtained optimal defect-free ZPEI-TFC membranes exhibited a lower roughness (3.3 ± 0.3 nm), a better surface hydrophilicity, and a smaller pore size (238 Da of MWCO). The positively charged ZPEI-TFC membranes (isoelectric point at pH 8.05) showed higher rejections toward both divalent cationic (MgCl2, 93.0%) and anionic (Na2SO4, 96.1%) salts with a water permeation flux of up to 81.0 L·m-2·h-1 at 6 bar, which surpassed currently reported membranes. More importantly, mainly owing to N-oxide zwitterion with strong hydration capability, ZPEI-TFC membranes displayed a high flux recovery ratio (97.0%) toward a model protein contaminant (bovine serum albumin), indicating good anti-fouling properties. Therefore, the novel N-oxide zwitterion functionalized positively charged nanofiltration membranes provide an alternative for water desalination and sewage reclamation.

A Phosphorous-Based Bi-Functional Flame Retardant Based on Phosphaphenanthrene and Aluminum Hypophosphite for an Epoxy Thermoset.

A phosphorous-based bi-functional compound HPDAl was used as a reactive-type flame retardant (FR) in an epoxy thermoset (EP) aiming to improve the flame retardant efficiency of phosphorus-based compounds. HPDAl, consisting of two different P-groups of aluminum phosphinate (AHP) and phosphophenanthrene (DOPO) with different phosphorous chemical environments and thus exerting different FR actions, exhibited an intramolecular P-P groups synergy and possessed superior flame-retardant efficiency compared with DOPO or AHP alone or the physical combination of DOPO/AHP in EP. Adding 2 wt.% HPDAl made EP composites acquire a LOI value of 32.3%, pass a UL94 V-0 rating with a blowing-out effect, and exhibit a decrease in the heat/smoke release. The flame retardant modes of action of HPDAl were confirmed by the experiments of the scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetry-Fourier transform infrared spectroscopy-gas chromatograph/mass spectrometer (TG-FTIR-GC/MS). The results indicate that the phosphorous-based FRs show different influences on the flame retardancy of composites, mainly depending on their chemical structures. HPDAl had a flame inhibition effect in the gas phase and a charring effect in the condensed phase, with a well-balanced distribution of P content in the gas/condensed phase. Furthermore, the addition of HPDAl hardly impaired the mechanical properties of the matrix due to the link by chemical bonds between them.

AtCircDB: a tissue-specific database for Arabidopsis circular RNAs.

Circular RNAs are widely existing in eukaryotes. However, there is as yet no tissue-specific Arabidopsis circular RNA database, which hinders the study of circular RNA in plants. Here, we used 622 Arabidopsis RNA sequencing data sets from 87 independent studies hosted at NCBI SRA and developed AtCircDB to systematically identify, store and retrieve circular RNAs. By analyzing back-splicing sites, we characterized 84 685 circular RNAs, 30 648 tissue-specific circular RNAs and 3486 microRNA-circular RNA interactions. In addition, we used a metric (detection score) to measure the detection ability of the circular RNAs using a big-data approach. By experimental validation, we demonstrate that this metric improves the accuracy of the detection algorithm. We also defined the regions hosting enriched circular RNAs as super circular RNA regions. The results suggest that these regions are highly related to alternative splicing and chloroplast. Finally, we developed a comprehensive tissue-specific database (AtCircDB) to help the community store, retrieve, visualize and download Arabidopsis circular RNAs. This database will greatly expand our understanding of circular RNAs and their related regulatory networks. AtCircDB is freely available at http://genome.sdau.edu.cn/circRNA.

Confined-walking mode for an elliptical polarized undulator and its application.

Elliptical polarized undulators (EPUs) are broadly used in the soft X-ray energy range. They have the advantage of providing photons with both varied energy and polarization through adjustments to the value of the gap and/or shift magnet arrays in an undulator. Yet these adjustments may create a disturbance on the stability of the electron beam in a storage ring. To correct such a disturbance, it is necessary to establish a feed-forward table of key nodes in the gap-shift-defined two-dimensional parameter space. Such a table can only be scanned during machine-study time. For a free-walking mode, whereby an undulator is allowed to manoeuvre in the whole gap-shift space, all the key nodes need to be scanned at the expense of a large amount of machine-study time. This will greatly delay the employment of a full-polarization capable undulator (especially circularly polarized). By analyzing data-collecting patterns of user experiments, this paper defines a reduced set of key nodes in gap-shift parameter space, with the number of key nodes to be scanned for feed-forwarding scaled down to one-third of the original; and introduces a new walking mode for EPUs: confined-walking mode, whereby the undulator is manoeuvred only within the reduced set of key nodes. Such a mode is firstly realized on the EPUs at the DREAMLINE beamline at Shanghai Synchrotron Radiation Facility (SSRF). Under confined-walking mode, the undulator movements are stable and there is no obvious disturbance to the electron beam with the feed-forward system in operation. Successful experiments have been carried out using the circularly polarized light obtained via the new walking mode. This mode is expected to be applied to future EPUs at SSRF with the increasing requirements for various polarization modes.

Diffusion kurtosis imaging in sacroiliitis to evaluate the activity of ankylosing spondylitis.

BACKGROUND: Conventional magnetic resonance (MR) imaging is limited in providing sufficient information on microstructure or in quantitatively evaluating certain inflammation processes. Functional MR sequences such as diffusion kurtosis imaging (DKI) might help to evaluate the sacroiliac joint in ankylosing spondylitis (AS) patients. PURPOSE: To explore the application of DKI in evaluating the disease activity of AS. STUDY TYPE: Prospective. POPULATION: Forty-four patients with a diagnosis of AS according to the Assessment in SpondyloArthritis International Society (ASAS) criteria. FIELD STRENGTH/SEQUENCE: 3.0T MRI including the DKI sequence (b = 0, 500, 1000, 1500, 2000 s/mm2 ). STATISTICAL TESTS: Two-independent-samples t-test and one-way analysis of variance (ANOVA) were used to compare the DKI parameters among different groups, and post-hoc Scheffe's method was adopted. Receiver operating characteristic (ROC) analysis and Spearman's rank correlation were performed to test the diagnostic performance of DKI parameters in distinguishing different activity grades and the correlation between them, respectively. ASSESSMENT: AS disease activity was evaluated according to the Ankylosing Spondylitis Disease Activity Score (ASDAS), and four disease activity states were chosen by consensus: inactive disease and moderate, high, and very high disease activity. The three cutoffs selected to separate these states were: 1.3, 2.1, and 3.5 units, respectively. RESULTS: The corrected ADC (D) and apparent diffusion coefficient (ADC) values of sacroiliac joints in the active group were significantly higher, while the the kurtosis of diffusion (K value) value was significantly lower than those of the inactive group (all P < 0.001). The D value performed best in distinguishing different activity grades (all P < 0.001). The D and ADC values correlated positively, while the K value correlated negatively, with activity grade significantly (r = 0.918, 0.798, and -0.765, respectively; all P < 0.001). DATA CONCLUSION: DKI of sacroiliac joints might be useful to evaluate the disease activity of AS. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:101-108.

Seed prioritized unwrapping (SPUN) for MR phase imaging.

BACKGROUND: Region-growing-based phase unwrapping methods have the potential for lossless phase aliasing removal, but generally suffer from unwrapping error propagation associated with discontinuous phase and/or long calculation times. The tradeoff point between robustness and efficiency of phase unwrapping methods in the region-growing category requires improvement. PURPOSE: To demonstrate an accurate, robust, and efficient region-growing phase unwrapping method for MR phase imaging applications. STUDY TYPE: Prospective. SUBJECTS, PHANTOM: normal human subjects (10) / brain surgery patients (2) / water phantoms / computer simulation. FIELD STRENGTH/SEQUENCE: 3 T/gradient echo sequences (2D and 3D). ASSESSMENT: A seed prioritized unwrapping (SPUN) method was developed based on single-region growing, prioritizing only a portion (eg, 100 seeds or 1% seeds) of available seed voxels based on continuity quality during each region-growing iteration. Computer simulation, phantom, and in vivo brain and pelvis scans were performed. The error rates, seed percentages, and calculation times were recorded and reported. SPUN unwrapped phase images were visually evaluated and compared with Laplacian unwrapped results. STATISTICAL TESTS: Monte Carlo simulation was performed on a 3D dipole phase model with a signal-to-noise ratio (SNR) of 1-9 dB, to obtain the mean and standard deviation of calculation error rates and calculation times. RESULTS: Simulation revealed a very robust unwrapping performance of SPUN, reaching an error rate of <0.4% even with SNR as low as 1 dB. For all in vivo data, SPUN was able to robustly unwrap the phase images of modest SNR and complex morphology with visually minimal errors and fast calculation speed (eg, <4 min for 368 × 312 × 128 data) when using a proper seed priority number, eg, Nsp = 1 or 10 voxels for 2D and Nsp = 1% for 3D data. DATA CONCLUSION: SPUN offers very robust and fast region-growing-based phase unwrapping, and does not require any tissue masking or segmentation, nor poses a limitation over imaging parameters. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:62-70.

Role of intravoxel incoherent motion MRI in early assessment of the response of esophageal squamous cell carcinoma to chemoradiotherapy: A pilot study.

BACKGROUND: Since definitive concurrent chemoradiotherapy (CRT) is standard therapy for inoperable esophageal squamous cell carcinoma (ESCC), early evaluation of treatment response is crucial for patients and would be useful in assessing response, especially in patients with severe side effects. PURPOSE: To explore the feasibility of intravoxel incoherent motion (IVIM) MRI in the early assessment of treatment response to CRT. STUDY TYPE: Prospective. POPULATION: Twenty-three inoperable ESCC patients. SEQUENCE: IVIM 3T MRI of nine b values (0, 25, 50, 75, 100, 150, 200, 500 and 800 s/mm2 ) was performed at four timepoints: pre-CRT (within 5 days before CRT), mid-CRT (2-3 weeks after the start of CRT), end-CRT (within 5 days after the end of CRT), and post-CRT (1 month after the end of CRT). ASSESSMENT: IVIM-based parameters and ADC were analyzed independently by two radiologists and treatment response was assessed by the Response Evaluation Criteria in Solid Tumors (RECIST). STATISTICAL TESTS: Analyses of variance for repeated measurements were conducted to observe dynamic changes of IVIM-based parameters (D, f, and D*) and ADC during CRT. The parameters and their change percentages (Δ%) were compared between complete response (CR) and partial response (PR) by Mann-Whitney U-test. Diagnostic performance of parameters in predicting response was tested with receiver-operating characteristic curve analysis. RESULTS: ADC, D, and f increased significantly during CRT (P < 0.001, < 0.001, and 0.001, respectively). ADC, f, Δ%ADC, and Δ%D at mid-CRT in CR group were significantly higher than those in the PR group (P = 0.002, 0.013, 0.005, and 0.011, respectively). D combined with f and ADC had highest area under curve (0.917) in identifying CR from PR. DATA CONCLUSION: IVIM parameters proved useful in assessing response to definitive concurrent CRT for inoperable ESCC and combined with ADC at an early stage of treatment was a good predictor of response. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2018;48:349-358.

Comparison of 68Ga-PSMA-11 PET-CT with mpMRI for preoperative lymph node staging in patients with intermediate to high-risk prostate cancer.

BACKGROUND: To evaluate the diagnostic value of 68Ga-PSMA-11 PET-CT with multiparametric magnetic resonance imaging (mpMRI) for lymph node (LN) staging in patients with intermediate- to high-risk prostate cancer (PCa) undergoing radical prostatectomy (RP) with pelvic lymph node dissection (PLND). METHODS: We retrospectively identified 42 consecutive patients with intermediate- to high-risk PCa according to D'Amico and without concomitant cancer. Preoperative 68Ga-PSMA-11 PET-CT, pelvic mpMRI and subsequent robot assisted laparoscopic RP with PLND were performed in all patients. RESULTS: Among 42 patients assessed, the preoperative PSA value, Gleason score, pT stage and intraprostatic PCa volume of patients with LN metastases were all significantly higher than those without metastases (P = 0.029, 0.028, 0.004, respectively). The average maximum standardized uptake value (SUV) of 68Ga-PSMA-11 PET-CT positive PCa of patients with or without LN metastases were 13.10 (range 6.12-51.75) and 7.22 (range 5.4-11.2), respectively (P < 0.001). 68Ga-PSMA-11 PET-CT and pelvic mpMRI had the ability of succeed on preoperative definite accurate diagnosis and accurate localization of primary PCa in all 42 patients. Fifteen patients (35.71%) had a pN1 stage. 51 positive LN were found. Both 68Ga-PSMA-11 PET-CT and pelvic mpMRI displayed brillient patient-based and region-based sensitivity, specificity, negative predictive value and positive predictive value. There was no statistical difference for the detection of LNMs according to the diameter of the LNMs between 68Ga-PSMA-11 PET-CT and mpMRI in this study. CONCLUSIONS: Both 68Ga-PSMA-11 PET-CT and mpMRI performed great value for LN staging in patients with intermediate- to high-risk PCa undergoing RP with PLND. However, despite excellent performance of 68Ga-PSMA-11 PET-CT, it cannot replace mpMRI that remains excellent for lymph node staging.

Research on sustainable collaborative scheduling problem of multi-stage mixed flow shop for crankshaft components.

The crankshaft manufacturing process primarily comprises machining, single jacket, and double jacket stages. These stages collectively produce substantial carbon emissions, which significantly impact the environment. Low-carbon energy development and humanity's future are closely related. To promote the sustainable development of crankshaft manufacturing enterprises and improve the production efficiency of crankshafts, research on sustainable collaborative scheduling problems in multi-stage mixed flow shop for crankshaft components is conducted. In addition, the transportation process of related workpieces in the crankshaft manufacturing process, which generally have a large mass, also produces substantial carbon emissions. This paper constructs a multi-objective integer optimization model based on the manufacturing process characteristics of crankshaft components, with minimizing the maximum manufacturing time and carbon emissions as optimization objectives. Considering the complexity of the problem, a comprehensive algorithm integrating moth-flame optimization and NSGA-III is used to solve the mathematical model. Through case experiments, the integrated algorithm is compared and analysed with four classic multi-objective optimization algorithms: NSGA-III, NSGA-II, MOEA/D, and MOPSO. The experiments demonstrate that the algorithm presented in this paper offers significantly enhanced optimization efficiency in solving the problem under study compared to other algorithms. Moreover, this paper compares multi-stage collaborative scheduling and non-collaborative scheduling in the crankshaft manufacturing process, ultimately demonstrating that collaborative scheduling is more conducive to the sustainable development of manufacturing enterprises. The results indicate that the annual carbon emissions can reduce about 3.6 ton.

Multi-objective optimization of dual resource integrated scheduling problem of production equipment and RGVs considering conflict-free routing.

In flexible job shop scheduling problem (FJSP), the collision of bidirectional rail guided vehicles (RGVs) directly affects RGVs scheduling, and it is closely coupled with the allocation of production equipment, which directly affects the production efficiency. In this problem, taking minimizing the maximum completion time of RGVs and minimizing the maximum completion time of products as multi-objectives a dual-resource integrated scheduling model of production equipment and RGVs considering conflict-free routing problem (CFRP) is proposed. To solve the model, a multi-objective improved discrete grey wolf optimizer (MOID-GWO) is designed. Further, the performance of popular multi-objective evolutionary algorithms (MOEAs) such as NSGA-Ⅱ, SPEA2 and MOPSO are selected for comparative test. The results show that, among 42 instances of different scales designed, 37, 34 and 28 instances in MOID-GWO are superior to the comparison algorithms in metrics of generational distance (GD), inverted GD (IGD) and Spread, respectively. Moreover, in metric of Convergence and Diversity (CD), the Pareto frontier (PF) obtained by MOID-GWO is closer to the optimal solution. Finally, taking the production process of a construction machinery equipment component as an example, the validity and feasibility of the model and algorithm are verified.

Injectable Phage-Loaded Microparticles Effectively Release Phages to Kill Methicillin-Resistant Staphylococcus aureus.

The increasing prevalence of bacterial multidrug antibiotic resistance has led to a serious threat to public health, emphasizing the urgent need for alternative antibacterial therapeutics. Lytic phages, a class of viruses that selectively infect and kill bacteria, offer promising potential as alternatives to antibiotics. However, injectable carriers with a desired release profile remain to be developed to deliver them to infection sites. To address this challenge, phage-loaded microparticles (Phage-MPs) have been developed to deliver phages to the infection site and release phages for an optimal therapeutic effect. The Phage-MPs are synthesized by allowing phages to be electrostatically attached onto the porous polyethylenimine-modified silk fibroin microparticles (SF-MPs). The high specific surface area of SF-MPs allows them to efficiently load phages, reaching about 1.25 × 1010 pfu per mg of microparticles. The Phage-MPs could release phages in a controlled manner to achieve potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Unlike the diffuse biodistribution of free phages post-intraperitoneal injection, Phage-MPs could continuously release phages to effectively boost the local phage concentration at the bacterial infection site after they are intraperitoneally injected into an abdominal MRSA-infected mouse model. In a mouse abdominal MRSA infection model, Phage-MPs significantly reduce the bacterial load in major organs, achieving an efficient therapeutic effect. Furthermore, Phage-MPs demonstrate outstanding biocompatibility both in vitro and in vivo. Overall, our research lays the foundation for a new generation of phage-based therapies to combat antibiotic-resistant bacterial infections.

Distributed shop scheduling: A comprehensive review on classifications, models and algorithms.

In the intelligent manufacturing environment, modern industry is developing at a faster pace, and there is an urgent need for reasonable production scheduling to ensure an organized production order and a dependable production guarantee for enterprises. Additionally, production cooperation between enterprises and different branches of enterprises is increasingly common, and distributed manufacturing has become a prevalent production model. In light of these developments, this paper presents the research background and current state of distributed shop scheduling. It summarizes relevant research on issues that align with the new manufacturing model, explores hot topics and concerns and focuses on the classification of distributed parallel machine scheduling, distributed flow shop scheduling, distributed job shop scheduling and distributed assembly shop scheduling. The paper investigates these scheduling problems in terms of single-objective and multi-objective optimization, as well as processing constraints. It also summarizes the relevant optimization algorithms and their limitations. It also provides an overview of research methods and objects, highlighting the development of solution methods and research trends for new problems. Finally, the paper analyzes future research directions in this field.

Research on Teleoperated Virtual Reality Human-Robot Five-Dimensional Collaboration System.

In the realm of industrial robotics, there is a growing challenge in simplifying human-robot collaboration (HRC), particularly in complex settings. The demand for more intuitive teleoperation systems is on the rise. However, optimizing robot control interfaces and streamlining teleoperation remains a formidable task due to the need for operators to possess specialized knowledge and the limitations of traditional methods regarding operational space and time constraints. This study addresses these issues by introducing a virtual reality (VR) HRC system with five-dimensional capabilities. Key advantages of our approach include: (1) real-time observation of robot work, whereby operators can seamlessly monitor the robot's real-time work environment and motion during teleoperation; (2) leveraging VR device capabilities, whereby the strengths of VR devices are harnessed to simplify robot motion control, significantly reducing the learning time for operators; and (3) adaptability across platforms and environments: our system effortlessly adapts to various platforms and working conditions, ensuring versatility across different terminals and scenarios. This system represents a significant advancement in addressing the challenges of HRC, offering improved teleoperation, simplified control, and enhanced accessibility, particularly for operators with limited prior exposure to robot operation. It elevates the overall HRC experience in complex scenarios.

3D-Heterojunction Based on Embedded Perovskite Micro-Sized Single Crystals for Fast Photomultiplier Photodetectors with Broad/Narrowband Dual-Mode.

A fast photomultiplier photodetector with a broad/narrowband dual mode is implemented using a new 3D heterostructure based on embedded perovskite micro-sized single crystals. Because the single-crystal size is smaller than the electrode size, the active layer can be divided into a perovskite microcrystalline part for charge transport and a polymer-embedded part for charge storage. This induces an additional radial interface in the 3D heterojunction structure, and allows a photogenerated built-in electric field in the radial direction, especially when the energy levels between the perovskite and embedding polymer are similar. This type of heterojunction has a small radial capacitance that can effectively reduce carrier quenching and accelerate the carrier response. By controlling the applied bias direction, up to 300-1000% external quantum efficiency (EQE) and microsecond response can be achieved not only in the wide range of ultraviolet to visible light from 320 to 550 nm, but also in the narrow-band response with a full width at half minimum (FWHM) of 20 nm. This shows great potential for applications in integrated multifunctional photodetectors.

How Do Phosphorus Compounds with Different Valence States Affect the Flame Retardancy of PET?

This work investigated the effect of different valence states of phosphorus-containing compounds on thermal decomposition and flame retardancy of polyethylene terephthalate (PET). Three polyphosphates-PBPP with +3-valence P, PBDP with +5-valence P and PBPDP with both +3/+5-valence P-were synthesized. The combustion behaviors of flame-retardant PET were studied and the structure-property relationships between the phosphorus-based structures with different valence states and flame-retardant properties were further explored. It was found that phosphorus valence states significantly affected the flame-retardant modes of action of polyphosphate in PET. For the phosphorus structures with +3-valence, more phosphorus-containing fragments were released in the gas phase, inhibiting polymer chain decomposition reactions; by contrast, those with +5-valence phosphorus retained more P in the condensed phase, promoting the formation of more P-rich char layers. It is worth noting that the polyphosphate containing both +3/+5-valence phosphorous tended to combine the advantage of phosphorus structures with two valence states and balance the flame-retardant effect in the gas phase and condensed phase. These results contribute to guiding the design of specified phosphorus-based structures of flame-retardant compounds in polymer materials.

One-Step Construction of the Positively/Negatively Charged Ultrathin Janus Nanofiltration Membrane for the Separation of Li+ and Mg2.

To coordinate the trade-off between the separation and permeation of the nanofiltration membrane for the separation of Mg2+/Li+, we regulated poly(ethyleneimine)/piperazine interface polymerization parameters to construct a positively/negatively charged ultrathin Janus nanofiltration membrane at a free aqueous-organic interface. At the optimized interfacial polymerization parameters, 0.03 wt % of piperazine reacted with trimethylbenzene chloride prior to poly(ethyleneimine), forming a primary polyamide layer with fewer defects or limiting large-scale defects of the polyamide layer. The controlled subsequent reaction of poly(ethyleneimine) and trimethylbenzene chloride results in a Janus nanofiltration membrane, with one side enriched with the carboxyl groups, the other side enriched with the amine groups, and a dense polyamide structure in the middle. Under the optimum conditions, the positive potential of the rear surface of the prepared membrane was 14.57 mV, and the water contact angle reached 71.31°, while the negative potential of the front surface was -25.48 mV, and the water contact angle was 12.93°, confirming a Janus membrane with opposite charges and large hydrophilicity differences in the front and rear surfaces. With a high cross-linking degree, a 40 nm thick polyamide layer is 29.09% more thinner than the traditional polyamide membrane. The ultrathin Janus nanofiltration membrane showed an excellent separation factor (SLi,Mg of 18.26), stability, and water permeability flux (10.6 L·m-2·h-1·bar-1). The rejections to MgCl2, CaCl2, MgSO4, and Na2SO4 are measured above 90% at a nearly constant permeability of 10.6 L·m-2·h-1·bar-1, particularly stable rejections to MgCl2 and Na2SO4.

Scalable synthesis of soluble crystalline ionic-graphdiyne by controlled ion expansion.

Graphdiyne (GDY) is a promising material possessing extensive electronic tunability, high π conjugacy, and ordered porosity at a molecular level for the sp/sp2-hybridized periodic structures. Despite these advantages, the preparation of soluble and crystalline graphdiyne is limited by the relatively compact stacking interactions, mostly existing in thick-layer and insoluble solids. Herein, we proposed a strategy of "framework charge-induced intercalation (FCII)" for the synthesis of a soluble (4.3 mg ml-1) and yet interlayer-expanded (∼0.6 Å) crystalline ionic graphdiyne, named as N+-GDY, through regulating the interlayer interactions. The skeleton of such a sample is positively charged, and then the negative ions migrate to the interlayer to expand the space, endowing the N+-GDY with solution processability. The crystal structure of N+-GDY is proved through analysis of HR-TEM images under different axes of observation and theoretical simulations. The resulting N+-GDY possesses high dispersity in organic solvents to produce a pure-solution phase which is conducive to the formation of oriented N+-GDY films, accompanied by exfoliation-nanosheet restacking. The film exhibits a conductivity of 0.014 S m-1, enabling its applications in electronic devices.

Anti-Diabetic Drugs Inhibit Bulimia Induced Obesity.

BACKGROUND: Obesity is primarily a consequence of food addiction. Drugs have been confirmed effective for weight loss more or less related to the functional connectivity in neural networks and metabolic patterns. Recent studies have shown that some anti-diabetic drugs, such as Metformin and Dapagliflozin have similar weight loss effects, however, their mechanisms are unclear. We hypothesized that the functional connectivity and energy metabolism might be associated with the mechanisms. METHODS: Male ob/ob mice were fed with high-fructose-fat-diet (HFFD) for 4 weeks to esteblish obesity model. Then mice were divided into normal saline (NS, as control), Metformin (Metformin, 50 mg/kg/day by gavage), and Dapagliflozin (Dapagliflozin, 10 mg/kg/day by gavage) groups. Functional connectivity amplitude of low-frequency signal fluctuations and regional cerebral blood volume (rCBV) quantification were statistically analyzed in the linear mixed model, meanwhile, metabolic pattern of intestinal cells (IECs) were also tested. RESULTS: Our results showed that Blood Oxygen on Level Depending (Bold) signaling responses, functional connectivity, and rCBV quantification tended to be attenuated in the Metformin group compared to the control and Dapagliflozin groups. While only Dapagliflozin prevented HFFD induced hyper survival of intestinal cells and hypertrophy of intestinal villus by reducing glycolysis levels. Both Metformin and Dapagliflozin are effective for weight loss. CONCLUSIONS: Our findings showed that Dapagliflozin and Metformin may inhibit bulimia induced obesity with different mechanisms. We speculate that Metformin may affect appetite regulation, while Dapagliflozin can affect the survival and metabolic patterns of intestinal cells, thus significantly affecting the absorption of nutrients. So, combining Metformin and Dapgliflozin may be more beneficial for clinical improvement in bulimia induced obesity.