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We report herein a photoinduced radical 1,3-dipolar cycloaddition between the 2-benzothiazolimines and tetrahydroisoquinoline derivatives with an organo-photocatalyst. A variety of benzothiazole-based hexahydroimidazo[2,1-a]isoquinoline architectures with great synthetic value were conveniently and efficiently constructed in moderate to good yields and excellent diastereoselectivities with highly tolerant functional groups. Moreover, the practicality and utility of this protocol were demonstrated by scale-up synthesis and facile elaboration. Preliminary mechanistic investigations indicated that the reaction proceeded via a visible-light-induced radical 1,3-dipolar cycloaddition pathway. This finding is expected to stimulate a more extensive exploration of the green and concise synthesis of structurally diverse heterocyclic molecules in the synthetic community.

Increasing the 1,3,5-trioxane (TOX) concentration in the equilibrated vapor phase of TOX–H2O system has been recognized as a challenge for the azeotrope. Ionic liquids (ILs) were used to improve the relative volatility of TOX to H2O and destroy the azeotrope in the TOX–H2O system. The vapor–liquid equilibrium of TOX–H2O system at 101.3 kPa was studied with the addition of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-hexyl-3-methylimidazolium hydrogen sulfate and 1-butyl-3-methylimidazolium nitrate, respectively. The results showed that the volatility of TOX increased with the increase in IL dosage. And the volatility of water decreased with the increase in IL dosage. The relative volatility of TOX to H2O was improved with the increase in ILs dosage. The azeotrope could be destroyed with an IL mole fraction of about 0.10. A non-random two-liquid (NRTL) model was successfully used to correlate the experimental data. The interaction parameters were obtained by fitting the experimental data with the model. The results indicated that a strong interaction existed between ILs and water. The strong interaction improved the volatility of TOX and inhibited the volatility of water, and then intensified the relative volatility of TOX to H2O. The results showed that an ILs with strong polarity and hydrophilicity may be a potential additive to improve the TOX concentration in the equilibrated vapor phase.

Water vapor nucleation on particle's surface plays an important role in dust removal, cloud formation, and particle measurement. However, the selectivity of nucleation sites and the nucleation characteristic of water molecule on the particle's surface are still unclear, especially for the aggregated particles. In this paper, the effects of particle wettability and aggregation modes on the selectivity of nucleation sites and the nucleation characteristics were investigated using molecular dynamics simulation. The results were compared with our earlier experimental findings. It illustrates how the contact angle of clusters, the growth velocity, and the growth duration are all influenced by the interaction coefficient between water and particles. Moreover, the nucleation sites of water molecules on the particle aggregation surface exhibit a definite selectivity. The primary indicator of this selectivity is the preferential nucleation of water molecules at the interfaces of linear chain aggregation particles, at the inner side of non-linear chain aggregation particles, and at the centers of ring aggregation. These results are in good agreement with our previous experimental findings. More significantly, additional research has revealed that subcritical-size clusters typically aggregate on two-particle surfaces spacing when the spacing smaller than the critical cluster size.

Amorphous carbon nitride with typical short-range order arrangement as an effective photocatalyst is worth exploring but remains a great challenge because its disordered structure induces severe recombination of photogenerated charge carriers. Herein, for the first time, we demonstrate that a hierarchical amorphous carbon nitride (HACN) with structural oxygen incorporation can be synthesized via a cyanuric acid-assisted melem hydrothermal process, accompanied by freeze-drying and pyrolysis. The complex composed of melem and cyanuric acid exhibiting a unique 3D self-supporting skeleton and significant phase transformation is responsible for the formation of an interconnected hierarchical framework and amorphous structure for HACN. These features are beneficial to enhance its visible light harvesting by the multiple-reflection effect within the architecture consisting of more exposed porous nanosheets and introducing a long band tail absorption. The well-designed morphology, band tail state, and oxygen doping effectively inhibit rapid band-to-band recombination of the photogenerated electrons and holes and facilitate subsequent separation. Accordingly, the HACN catalyst exhibits exceptional visible light (λ > 420 nm)-driven photoreduction for hydrogen production with a rate of 82.4 μmol h–1, which is 21.7 and 9.5 times higher than those of melem-derived carbon nitride and crystalline nanotube carbon nitride counterparts, respectively, and significantly surpasses those of most reported amorphous carbon nitrides. Our controlling of rearrangement of the in situ supramolecular self-assembly of melem oligomer using cyanuric acid directly instructs the development of highly efficient amorphous photocatalysts for converting solar energy into hydrogen fuel.

Interleukin-34 (IL-34) is a hematopoietic cytokine and a ligand of colony-stimulating factor 1 receptor (CSF-1R). Numerous studies have demonstrated that IL-34 is involved in several inflammatory diseases. Nevertheless, the role of IL-34 is obscure in community-acquired pneumonia (CAP) patients. This research aimed to assess the associations of serum IL-34 with severity and prognosis in CAP patients through a longitudinal study.

A premixer and grooved surface are designed to improve the micromixing performance of a spinning disc reactor (SDR). The inlets of the impinging jet provide an initial premixing of the two streams. The effects of premixing and grooved surface on the overall micromixing performance at different conditions are investigated systematically. The results show that premixing and trapezoidal groove surface could greatly intensify the global micromixing performance of SDR. Increasing the rotation speed and flow rate also significantly improves the micromixing effect. When the disc distance is lower than 0.80 mm, an extremely low inter disc distance deteriorates the micromixing. The effect of premixing on the micromixing performance of low viscosity streams is more significant than that of the spinning disc itself. However, for high viscosity streams, the micromixing performance strongly depends on the spinning disc. The flow patterns in the designed SDR were further studied. Three flow patterns, including film flow, film–filament transitional flow, and filament flow, were observed in SDR with a stator disc. High rotational speed, large disc spacing, and low volumetric flow rate are conducive to the formation of filament flow rather than film flow. Predicative dimensionless criteria for flow patterns were established. The results provide meaningful information for further intensifying the micromixing performance of SDR.

Low-dose positron emission tomography (PET) reconstruction algorithms manage to reduce the injected dose and/or scanning time in PET examination while maintaining the image quality, and thus has been extensively studied. In this article, we proposed a novel ultralow-dose reconstruction method for total-body PET. Specifically, we developed a deep learning model named ISS-Unet based on U-Net and introduced 3-D PixelUnshuffle/PixelShuffle pair in image space to reduce the training time and GPU memory. We then introduced two body sampling methods in the training patch preparation step to improve the training efficiency and local metrics. We also reported the misalignment artifacts that were often neglected in 2-D training. The proposed method was evaluated on the MICCAI 2022 Ultralow-Dose PET Imaging Challenge dataset and won the first prize in the first-round competition according to the comprehensive score combining global and local metrics. In this article, we disclosed the implementation details of the proposed method followed by the comparison results with three typical methods.

Dynamic PET imaging provides superior physiological information than conventional static PET imaging. However, the dynamic information is gained at the cost of a long scanning protocol; this limits the clinical application of dynamic PET imaging. We developed a modified Logan reference plot model to shorten the acquisition procedure in dynamic PET imaging by omitting the early-time information necessary for the conventional reference Logan model. The proposed model is accurate theoretically, but the straightforward approach raises the sampling problem in implementation and results in noisy parametric images. We then designed a self-supervised convolutional neural network to increase the noise performance of parametric imaging, with dynamic images of only a single subject for training. The proposed method was validated via simulated and real dynamic $^{{18}}\text{F}$ -fallypride PET data. Results showed that it accurately estimated the distribution volume ratio (DVR) in dynamic PET with a shortened scanning protocol, e.g., 20 minutes, where the estimations were comparable with those obtained from a standard dynamic PET study of 120 minutes of acquisition. Further comparisons illustrated that our method outperformed the shortened Logan model implemented with Gaussian filtering, regularization, BM4D and the 4D deep image prior methods in terms of the trade-off between bias and variance. Since the proposed method uses data acquired in a short period of time upon the equilibrium, it has the potential to add clinical values by providing both DVR and Standard Uptake Value (SUV) simultaneously. It thus promotes clinical applications of dynamic PET studies when neuronal receptor functions are studied.

Large quantities of titanium white waste acid (TWWA) are generated during TiO2production by the sulfate process. Recycling by concentration is the most widely used method to treat TWWA. However, serious fouling occurs during this process. The chemical composition of fouling obtained from a commercial plant was analyzed. The phase equilibria of CaSO4-FeSO4-H2SO4-H2O at 373.15 and 378.15 K were studied to elucidate the fouling mechanism. The fouling was mainly composed of CaSO4(anhydrite) (74.97 wt %) and TiO(OH)2(anatase) (24.48 wt %). The mass fractions of CaSO4and FeSO4in the equilibrium liquid phase of the CaSO4-FeSO4-H2SO4-H2O system increased with an increase in temperature and a decrease in H2SO4concentration. The Pitzer method was successfully employed to describe the equilibrium behavior. During the mixing of the recycled acid and the initial TWWA, some CaSO4(anhydrite) precipitated from the liquid phase, while some FeSO4·H2O dissolved in the liquid phase during the mixing and heating process. In the heating process, CaSO4(anhydrite) did not precipitate out from the liquid phase. It was thus concluded that CaSO4(anhydrite) precipitation during the mixing process is the key factor for the fouling on the heat exchanger surface during the primary evaporation process.

The reaction kinetics of phosphate ore particles reacting with excessive phosphoric acid was investigated. The effects of various operating parameters including reaction temperature (333.15–353.15 K), concentration of phosphoric acid (20–40 ωt% P2O5) and particle size (260, 190, 134, 96, 59 μm) on the reaction performance were investigated first. The results indicated that the reaction rate increased with the increase of reaction temperature, concentration of phosphoric acid, as well as the decrease of particle size. The Drozdov model could be used to describe the reaction behaviors. The activation energy results suggested that the rate-determining step was the diffusion of H+through the residual layer. The precipitation of insoluble phosphates would cover on the surface and lead to a decrease of dissolution extent. Controlling the product forms is crucial to the improvement of dissolution extent. The specific surface area of the phosphate ore also had a significant impact on the reaction rate and dissolution extent.

Rational design of effective non-noble metal-based electrocatalysts with high conductivity, abundant active sites, and superior stability for zinc–air batteries (ZABs) with long-term cycling ability is highly demanded. A suitable carrier that can provide a high specific surface and porous structure to facilitate the exposure of active sites and the diffusion of reactants, products, and charges is of great importance. Herein, one-dimensional (1D) Fe–Zn-doped porous carbon fibers (Fe–Zn@NCF) are prepared from a polymer fiber matrix encapsulated with Fe-doped ZIF-8 nanocrystals by pyrolysis. The Fe–Zn@NCF exhibits good performance toward the oxygen reduction reaction or oxygen evolution reaction. Impressively, the assembled ZAB with Fe–Zn@NCF as the catalyst delivers a maximum peak power density of 184.6 mW cm–2, excellent rechargeability with a round-trip efficiency of 66.5%, and stable operation over 1600 h (800 cycles). These excellent electrocatalytic performances can be attributed to the Fe/Zn-based dual catalytic active sites and the 1D carbon fiber support of the catalyst with a hierarchical porous structure, a large surface area, and high conductivity that can facilitate fast mass and electron transportation and maintain the structural stability of the catalyst during cycling.

In the process of evolution, the multi-objective firefly algorithm (MOFA) has low optimisation accuracy and is prone to premature convergence, resulting in poor distribution and convergence of the population. To solve this problem, a multi-objective firefly algorithm (MOFA-LC) combining logistic mapping and cross-mutation was proposed. To improve the distribution of the population, the initial population with good ergodicity and uniformity was generated by logistic mapping. To improve population convergence, Levy flights and non-dominated sorting are used to improve the position updating formula. After the individual position updating, the cross-mutation method in the genetic algorithm can be used to improve the optimisation accuracy of the algorithm and make it jump out of the local optimal, overcome the intelligent convergence of the algorithm, and maintain the convergence of the population. In the experimental part, two typical test functions are selected to plot the IGD convergence curves of MOFA-LC and 11 recent multi-objective optimisation algorithms. The results show that MOFA-LC has obvious advantages over other algorithms.

With the industrial development and improvement of living standards, carbon dioxide emissions are increasing year on year and have been causing serious environmental issues, such as global warming. Hence, it is urgent to develop effective, low-cost technologies for trapping or converting CO2. The electrochemical reduction of carbon dioxide can not only solve the issue of global warming but also can effectively convert CO2into useful chemicals. For the efficient electrochemical reduction of carbon dioxide under mild conditions, high-performance catalysts are required. In this work, metallic tin and bismuth compounds were deposited on carbon paper viaa facile co-electrodeposition strategy and their catalytic performance was comprehensively evaluated. The results showed that the SnBi catalyst with the Sn2+/Bi3+molar ratio of 1.0(Sn1.0Bi) in the preparation solution offered the largest formic acid selectivity with an excellent FE of 96.4% at a partial current density of 36.7 mA cm−2when the reduction potential was −1.06 V vs.RHE. A good formic acid yield of 684.7 μmol h−1cm−2was achieved from this catalyst. The formic acid yield further increased to 733.2 μmol h−1cm−2using the Sn0.5Bi catalyst (0.5 Sn2+/Bi3+molar ratio) at a slightly reduced selectivity with a lower FE of 96.1% at −1.06 V vs.RHE and increased partial current density of 40.3 mA cm−2. The results are better than most of the reported electrocatalysts. The helical pyramid-like structure of the SnBi catalyst provides a large exposed area with a large number of active sites and a large number of screw dislocation defects. Its fast electron transfer is favorable for the formation of the key radical of CO2−intermediate and the tin metal oxide/bismuth metal oxide interface is favorable for stabilizing CO2−with suppressed hydrogen evolution reaction. In addition, the electronic coupling between Sn and Bi at their interfaces strengthens the pathway involving the OCHO intermediate, which is important to promote the conversion of CO2to formic acid. In conclusion, the SnBi catalyst with a helical platform structure is a promising and efficient catalyst for the reduction of CO2.

The exploitation of highly active bifunctional electrocatalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in acidic media has been a subject receiving immense interest. However, the existing catalysts usually suffer from low catalytic efficiency and poor corrosion resistance under acidic conditions. Herein, we report a facile molten salt method to fabricate ruthenium dioxide nanoparticles supported by hierarchically porous carbon (RuO2/PC) as a bifunctional electrocatalyst for full water splitting under strong acidic conditions. The formation of a densely populated nanocrystalline RuO2/carbon heterostructure helps expose catalytic sites, accelerates the mass transfer rate, and further enhances the acid resistance of RuO2nanoparticles. The as-synthesized RuO2/PC consequently exhibits superior catalytic performance for the OER with an overpotential of 181 mV upon 10 mA cm−2compared to that of the commercial RuO2(343 mV) and a comparable performance to Pt/C for the HER (47.5 mV upon 10 mA cm−2) in 0.5 M H2SO4. The RuO2/PC shows promising stability with little degradation over ∼24 h. Impressively, the water electrolyzer based on RuO2/PC shows an overpotential of 326 mV at 10 mA cm−2, much lower than that of the electrolyzer based on the combination of Pt/C and RuO2(400 mV), indicating its great potential towards practical application.

We retrospectively collected drug susceptibility data of Klebsiella pneumoniaefrom six tertiary hospitals in Shaoxing City in 2019 and performed a comparative analysis of drug resistance among different hospitals, sexes, ages, and specimens. In total, 1954 strains were identified. The antibiotic resistance rate varied from 4.42% to 36.18%. Most K. pneumoniaewere still susceptible to carbapenems and tigecycline, with resistance rates of less than 10%. Drug resistance was relatively mild in Shaoxing Traditional Chinese Medicine Hospital and Shaoxing Maternal and Children Health Hospital, but most severe in Affiliated Hospital of Shaoxing University. Specimens were primarily obtained from elderly and male patients, and the resistance rate increased with age. The specimens were mostly collected from the respiratory and urinary tracts. No carbapenem-resistant strains were collected in 112 isolates from patients under 20 years of age. The ratio of carbapenem-resistant K. pneumoniaeisolates was highest in blood-isolated strains (23.86%), and that of extended-spectrum beta-lactamase positive strains was highest in non-blood-sterile body fluids (37.37%). The resistance spectrum of K. pneumoniaevaried between hospitals in the same area. Elderly and male patients, non-sterile body fluids, and blood source strains should be seriously considered in empirical treatment.HighlightsPrevention and control should be strengthened in hospitals with high rate of drug resistance.Strengthen screening of drug-resistant bacteria in specific populations.Transferred patients should be alerted to the bacterial drug resistance status.

The Cu-ZnO/Al2O3(CZA) catalyst was prepared by an innovated microemulsion antisolvent extraction method. The solution of Cu(CH3COO)2and Zn(CH3COO)2was encapsulated in a microemulsion with ethyl acetate as the outer layer. Then ethyl acetate was used as the antisolvent to precipitate the precursors. The results showed that the Cu and Zn in the as-prepared catalysts were closely adjacent and had a stronger interaction compared to the catalysts prepared by the conventional impregnated method. The catalytic performance was evaluated under the conditions of 0.1 MPa, 300–400 °C, and a space velocity of 72000 mL·g–1·h–1. Compared with the corresponding conventional impregnation catalysts, the as-prepared CZA catalysts with 5%, 10%, and 15% loadings showed CO2conversion increments of 0.8%, 2.1%, and 3.0%, respectively. TPSR analysis showed that the reaction mechanism in Cu–Zn catalysts was through an associative mechanism, and more Cu-ZnO interfaces could promote the reaction. These findings will facilitate the rational design of CO2hydrogenation catalysts.

Synergistic interaction derived by a heterointerface structure on the surface of metal oxide catalysts has a crucial role in improving the catalytic activity. In this work, MnOxnanoparticles were dispersed on the surface of CeO2nanorods to generate a MnOx–CeO2heterointerface structure, and its effect on toluene adsorption and catalytic oxidation performance was investigated. The results show that MnOxis well dispersed on CeO2nanorods, and the interaction of Mn–Ce significantly reduces the strength of the Ce–O bond and increases the conversion of Ce4+to Ce3+, which further promotes the activation of oxygen. Compared to MnOxon SiO2without synergistic interaction, the enhancement of toluene adsorption on this novel MnOx–CeO2hetero-interface structure can also make a great contribution to the improvement of the catalytic reaction process. Among them, the synergistic effect of CeO2–MnOxcould reduce the temperature of 90% toluene conversion to 210 °C (this value is 83 °C lower than that over pure CeO2nanorods). In addition, the fresh MnOx–CeO2catalyst not only shows excellent stability and moisture resistance but also retains highly low-temperature activity even after thermal aging at 750 °C for 100 h.

A ternary mixture of N-methyldiethanolamine + sulfolane + water called Sulfinol-M is usually used as an absorbent to remove acid gas species from natural gas. The surface tension and viscosity of N-methyldiethanolamine + sulfolane + water ternary mixtures with different compositions in the temperature range from 298.2 to 323.2 K were measured at atmospheric pressure. The surface tension of the mixed solution decreased linearly with the increasing temperature. The surface tension deviation was negative and increased with the decrease of the water content in the solutions. The viscosity–temperature dependence was nonlinear and conformed to an extended Arrhenius equation. When the concentration of N-methyldiethanolamine was ≤50 wt %, the viscosity deviation was negative and increased with the increasing temperature. For the surface tension of ternary mixtures, the average absolute relative deviation (AAD%) values of the simplified extended Wilson model and the simplified FLW model were 0.69 and 1.37, respectively. The modified Grunberg–Nissan model and Jouyban–Acree model were used to correlate the viscosity data, and the AAD% values were 3.26 and 8.61, respectively.

Phototherapy for non-invasive cancer treatment has been extensively studied. An urgent challenge in phototherapy application is to fabricate appropriate targeted agents to achieve efficient therapeutic effect. Herein, a molecular and supramolecular approach for targeting phototherapy was reasonably designed and realized through the axial sulfonate modification of silicon(IV) phthalocyanines (Pcs), followed by supramolecular interaction with albumin. This approach can not only improve the photoactivities (e.g., fluorescence emission and reactive oxygen species production) of the Pcs but also enhance their tumor targeting. Most importantly, one of the deigned Pcs (4) can target HepG2 cells through dual cell pathways, leading to an extremely high phototoxicity with an EC50(i.e., concentration of Pcs to kill 50% of cells under light irradiation) value of 2.0 nM. This finding presents a feasible strategy to realize efficient targeting phototherapy.

AbstractHepatitis B virus (HBV) infection is an important problem threatening human health. After HBV virus invades human body, it may assemble a complete virus particle in the cytoplasm to trigger the immune reaction, especially the interaction between the HBV virus and the host that mediated by CD8+T cell. We collected the sequences of HBV from the HBVdb database, then screened candidate mutation sites in Chinese, European and American populations based on conservation and physicochemical properties. After that we constructed the three-dimensional structure of Major histocompatibility complex class I (MHC I) -peptide complexes, performed molecular docking, run molecular dynamics to compare the binding free energy, stability, and affinity of MHC I-peptide complexes with the aim to estimate the effect of peptide mutation. The specific HBV virus subtypes of the Chinese, European and American population were studied and the candidate mutation sites were used to predict the mutant peptide antigen. Finally, based on physical and chemical properties and peptide antigen prediction scores, 21 HBV mutation sites were selected. Then combined with specific Human lymphocyte antigen (HLA) subtypes, 11 mutations were found to have a significant negative impact on affinity, stability and binding free energy. Overall, our work found important potential mutations, which provide an evaluation of HBV mutations and a clue of it in immunotherapy. Communicated by Ramaswamy H. Sarma

Potassium ion batteries (PIBs) are expected to become the next large-scale energy storage candidates due to its low cost and abundant resources. And the covalent organic framework (COF), with designable periodic organic structure and ability to organize redox active groups predictably, has been considering as the promising organic electrode candidate for PIB. Herein, we report the facile synthesis of the cyano-COF with Co coordination via a facile microwave digestion reaction and its application in the high-energy potassium ion batteries for the first time. The obtained COF-Co material exhibits the enhanced π–π accumulation and abundant defects originated from the Co interaction with the two-dimensional layered sheet structure of COF, which are beneficial for its energy-storage application. Adopted as the inorganic-metal boosted organic electrode for PIBs, the COF-Co with Co coordination can promote the formation of the π–K+interaction, which could lead to the activation of aromatic rings for potassium-ion storage. Besides, the porous two-dimensional layered structure of COF-Co with abundant defects can also promote the shortened diffusion distance of ion/electron with promoted K+insertion/extraction ability. Enhanced cycling stability with large reversible capacity (371 mAh g–1after 400 cycles at 100 mA g–1) and good rate properties (105 mAh g–1at 2000 mA g–1) have been achieved for the COF-Co electrode.