The hydroformylation of alkenes with CO and H2 to manufacture aldehydes is one of the most large-scale chemical reactions. However, an efficient and recyclable heterogeneous catalyst for alkene ...hydroformylation is extremely in demand in academia and industry. In this study, a sulfated carbon nitride supported rhodium particle catalyst (Rh/S-g-C3N4) was successfully synthesized via an impregnation-borohydride reduction method and applied in the hydroformylation of alkenes. The catalysts were characterized by XRD, FTIR, SEM, TEM, XPS, and nitrogen adsorption. The influence of the sulfate content, pressure of syngas, temperature, and reaction time, as well as the stability of Rh/S-g-C3N4, on the hydroformylation was examined in detail. The delocalized conjugated structure in g-C3N4 can lead to the formation of electron-deficient aromatic intermediates with alkenes. The sulphate g-C3N4 has a defected surface owing to the formation of oxygen vacancies, which increased the adsorption and dispersion of RhNPs on the surface of g-C3N4. Therefore, Rh/S-g-C3N4 exhibited an outstanding catalytic performance for styrene hydroformylation (TOF = 9000 h−1), the conversion of styrene could reach 99.9%, and the regioselectivity for the branched aldehyde was 52% under the optimized reaction conditions. The catalytic properties of Rh/S-g-C3N4 were also studied in the hydroformylation of various alkenes and displayed an excellent catalytic performance. Furthermore, the reuse of Rh/S-g-C3N4 was tested for five recycling processes, without an obvious decrease in the activity and selectivity under the optimum reaction conditions. These findings demonstrated that Rh/S-g-C3N4 is a potential catalyst for heterogeneous hydroformylation.
Coronavirus disease 2019 (COVID-19) has become a worldwide pandemic. Hospitalized patients of COVID-19 suffer from a high mortality rate, motivating the development of convenient and practical ...methods that allow clinicians to promptly identify high-risk patients. Here, we have developed a risk score using clinical data from 1479 inpatients admitted to Tongji Hospital, Wuhan, China (development cohort) and externally validated with data from two other centers: 141 inpatients from Jinyintan Hospital, Wuhan, China (validation cohort 1) and 432 inpatients from The Third People’s Hospital of Shenzhen, Shenzhen, China (validation cohort 2). The risk score is based on three biomarkers that are readily available in routine blood samples and can easily be translated into a probability of death. The risk score can predict the mortality of individual patients more than 12 d in advance with more than 90% accuracy across all cohorts. Moreover, the Kaplan–Meier score shows that patients can be clearly differentiated upon admission as low, intermediate, or high risk, with an area under the curve (AUC) score of 0.9551. In summary, a simple risk score has been validated to predict death in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); it has also been validated in independent cohorts.
In this paper, a time-domain hydroelastic method for very large floating structures (VLFS′) in inhomogeneous waves is developed based on Cummins' equation. By discretizing the continuous VLFS into ...rigid modules connected by elastic beam elements, the inhomogeneous wave effect can be considered by adopting different wave spectra over different regions of the VLFS. In this method, the frequency-domain hydrodynamic coefficients, considering the hydrodynamic interactions between each floating module, are transformed into the time-domain hydroelastic model using Cummins' equation. Moreover, the time-domain wave excitation forces on the modules in different regions are solved using different wave spectra. The hydroelastic responses of a freely floating structure in inhomogeneous regular and irregular waves are investigated. The results show that the inhomogeneity of waves has a significant effect on the bending moments, shear forces and torsional moments of the structure, especially for a wave direction of 90°, in which larger forces may be induced compared with the homogeneous waves.
•A discrete-modules-based time-domain hydroelasticity method for VLFS' is developed.•The proposed method is validated against the traditional frequency 3D hydroelasticity method.•Inhomogeneous wave effects to the hydroelastic responses of a freely floating VLFS are investigated.•The inhomogeneity of waves should be considered for VLFS' to assure a safe design.
In an urban environment, dual vertical axis wind turbines (VAWTs) are expected to demonstrate more advantage than horizontal axis wind turbine. For VAWT, solidity is one of the most important ...characteristics, while it has not been well studied. In this study, to investigate the effect of rotor solidity and other characteristics on the power output of counter-rotating dual VAWTs at different rotor centre spacings in a low turbulence intensity condition, twelve wind tunnel experiments for dual VAWTs and six wind tunnel experiments for an isolated VAWT were conducted. The results show that the effect of the dual VAWTs configuration on the VAWT power output is small compared with isolated VAWT under low wind speeds in an urban environment, but the effect exhibits a slight improvement with an increase in rotor solidity. As rotor solidity decreases, the sensitivity of the effect on rotor centre spacing increases. The effect of skewed flow on the power output of dual VAWTs are also well discussed. Furthermore, dual-VAWT systems are studied under real urban environment of a number of major cities such as Guangzhou, London, and Copenhagen. Potentials in different heights are compared with different configurations based on the city planning of those major cities.
•An experimental test on various dual-rotor system was conducted in a wind tunnel.•The relationship between solidity and the dual rotor system is analyzed.•The performance of the dual rotor system under skewed flow is discussed.•The potential of dual rotor system on building are studied in various major cities.
The degradability of specific organic micropollutants in constructed wetlands (CWs) may differ depending on the prevalence of oxic or anoxic conditions. These conditions are governed, among other ...factors, by the water saturation level in the system. This study investigated the removal of three environmentally-relevant organic micropollutants: bisphenol-group plasticizer bisphenol S (BPS), household-use insecticide fipronil (FPN) and non-steroidal anti-inflammatory drug ketoprofen (KTP) in the model CWs set up in an outdoor column system. BPS and KTP, in contrast to FPN, exhibit higher biodegradability potential under oxic conditions. The experimental CWs were operated under various saturation conditions: unsaturated, partially saturated and saturated, and mimicked the conditions occurring in unsaturated, partially-saturated intermittent vertical-flow CWs and in horizontal-flow CWs, respectively. The CWs were fed with synthetic household wastewater with the concentration of the micropollutants at the level of 30–45 μg/L. BPS and KTP exhibited contrasting behaviour against FPN in the CWs in the present experiment. Namely, BPS and KTP were almost completely removed in the unsaturated CWs without a considerable effect of plants, but their removal in saturated CWs was only moderate (approx. 50%). The plants had only a pronounced effect on the removal of BPS in saturated systems, in which they enhanced the removal by 46%. The removal of FPN (approx. 90%) was the highest in the saturated and partially-saturated CWs, with moderate removal (66.7%) in unsaturated systems. Noteworthy, partially-saturated CWs provided high or very high removal of all three studied substances despite their contrasting degradability under saturated and unsaturated conditions. Namely, their removal efficiencies in planted CWs were 95.9%, 94.5% and 81.6%, for BPS, KTP and FPN, respectively. The removal of the micropollutants in partially-saturated CWs was comparable or only slightly lower than in the best treatment option making it the performance all-rounder for the compounds with contrasting biodegradability properties.
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•Bisphenol S and ketoprofen exhibited contrasting behaviour against fipronil in CWs.•Bisphenol S and ketoprofen were efficiently removed in unsaturated CWs.•Fipronil elimination was enhanced in saturated CWs.•The presence of vegetation greatly enhanced the removal of bisphenol S.•Partially-saturated CWs overcame the limitations of saturated and unsaturated CWs.
Hydroformylation would be a promising alternative for partial technological process in petrochemical industry because it is a 100% atom-economical route for large-scale production of aldehydes and ...alcohols from olefins and synthesis gas (H2 and CO). However, there are still a few problems such as cost-intensive recycling and harsh operating conditions etc. encountering in the ligand-modified cobalt and rhodium as homogeneous catalysts in practical applications. Responding to the challenges, to exploit heterogeneous catalysts especially supported catalysts is desired and needs to make more efforts. Here, porous boron nitride (p-BN) with hierarchical structure is designed through a facile thermal polymerization procedure for catalyst support. The p-BN possesses nanorod morphology assembled by numerous highly crystallized hexagonal boron nitride (h-BN) nanoparticles with the diameter of about 20 nm as building blocks, thereby forming abundant interparticle pores. The Rh nanoparticles are then supported on p-BN by an impregnation-borohydride reduction method using RhCl3 as metal precursor, and the obtained catalyst of Rh nanoparticle supported on p-BN (Rh/p-BN) is applied in hydroformylation of styrene. The high porosity and accessible boron acid sites arising from hierarchical structure of p-BN nanorods make Rh nanoparticles homogeneously disperse on the surface of p-BN nanorods and also keep the diameter about 5 nm without further aggregations. Just for this reason, Rh/p-BN exhibits excellent activity of styrene hydroformylation with the highest turnover frequency of styrene as high as 12000 h−1, in comparison with other supported catalysts using different catalyst supports. Besides the detailed investigation of the catalytic properties of Rh/p-BN under different reaction conditions, the recycle of Rh/p-BN is also conducted for five times during which there is no significant decrease in catalytic activity. The present findings indicates that the combination of catalyst support of p-BN and metal nanoparticle catalysts could be an attractive strategy for designing heterogeneous hydroformylation catalysts.
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•Highly crystallized h-BN nanoparticles aggregate as building blocks to form the porous BN nanorods.•P-BN with porous structure and boron Lewis acid sites favors a simple adsorption mode of olefins.•The confinement of porous structure plays an important role for the formation of well-dispersed small-sized Rh particles.•Rh/p-BN exhibits a high catalytic performance for the hydroformylation of olefins.•The excellent catalytic activity is related with the pyrolysis time of BN.
The sudden increase in COVID-19 cases is putting high pressure on healthcare services worldwide. At this stage, fast, accurate and early clinical assessment of the disease severity is vital. To ...support decision making and logistical planning in healthcare systems, this study leverages a database of blood samples from 485 infected patients in the region of Wuhan, China, to identify crucial predictive biomarkers of disease mortality. For this purpose, machine learning tools selected three biomarkers that predict the mortality of individual patients more than 10 days in advance with more than 90% accuracy: lactic dehydrogenase (LDH), lymphocyte and high-sensitivity C-reactive protein (hs-CRP). In particular, relatively high levels of LDH alone seem to play a crucial role in distinguishing the vast majority of cases that require immediate medical attention. This finding is consistent with current medical knowledge that high LDH levels are associated with tissue breakdown occurring in various diseases, including pulmonary disorders such as pneumonia. Overall, this Article suggests a simple and operable decision rule to quickly predict patients at the highest risk, allowing them to be prioritized and potentially reducing the mortality rate.Early and accurate clinical assessment of disease severity in COVID-19 patients is essential for planning the allocation of scarce hospital resources. An explainable machine learning tool trained on blood sample data from 485 patients from Wuhan selected three biomarkers for predicting mortality of individual patients with high accuracy.
•The retention of ibuprofen by nanofiltration is discussed.•The influence of salt type and concentration on membrane process is illustrated.•Salt influences the ibuprofen-membrane interaction.•CaCl2 ...gives better IBU retention than other two salts of Na2SO4 and NaCl.
The retention of ibuprofen by a nanofiltration membrane (Desal 5 DK) was studied, considering the influence of the different co-existing salt (namely, NaCl, Na2SO4, CaCl2) with varying concentration (ionic strength from 10 to 100mM). The result shows that the Desal 5 DK cannot reject the ibuprofen satisfactorily (highest retention rate approximated to be ca.40%) in absence of salt, which agrees with the strong solute-membrane attraction. On the other hand, the presence of salt differentiates the membrane performance. An enhanced permeability of ibuprofen is only found when Na2SO4 is present, giving lowest retention rate compared with other cases (without salt and with chloride-induced salts). NaCl improves the ibuprofen retention in a moderate extent. Donnan exclusions of the anions and membrane charge screening may be involved for these two mixtures. CaCl2 gives the highest retention of ibuprofen mainly due to the specific interaction of calcium and carboxyl group, and the lowest adsorption of ibuprofen on membrane as well asacceptable permeate flux. Further study is needed to better understand the influence of salt on such emerging pollutants retention by membrane.
Type 1 diabetes (T1D), a complex autoimmune disease, is intricately linked to the gut's epithelial barrier function. Emerging evidence emphasizes the role of irisin, an exercise-related hormone, in ...preserving intestinal integrity. This study investigates whether irisin could delay T1D onset by enhancing the colon intestinal barrier. Impaired colon intestinal barriers were observed in newly diagnosed T1D patients and non-obese diabetic (NOD) mice, worsening with age and accompanied by islet inflammation. Using an LPS-induced colonic inflammation model, a dose-dependent impact of LPS on colon cells irisin expression, secretion, and barrier function was revealed. Exogenous irisin demonstrated remarkable effects, mitigating islet insulitis, enhancing energy expenditure, and alleviating autoimmune symptoms by reducing colon intestinal permeability. Single-cell RNA sequencing (scRNA-seq) highlighted irisin's positive impact on colon epithelial cell clusters, effectively restoring the intestinal barrier. Irisin also selectively modulated bacterial composition, averting potential bacterial translocation. Mechanistically, irisin enhanced colon intestinal barrier tight junction proteins through the AMPK/PI3K/AKT pathway, with FAM120A playing a crucial role. Irisin upregulated MUC3 expression, a protector against damage and inflammation. Harnessing irisin's exercise-mimicking properties suggests therapeutic potential in clinical settings for preventing T1D progression, offering valuable insights into fortifying the colon's intestinal barrier and managing autoimmune conditions associated with T1DM.
Intraperitoneal injection of irisin or AAV9-carrying irisin effectively reduced the incidence of diabetes in NOD mice. Irisin ameliorated intestinal barrier function by enhancing the expression of claudin-1 and ZO-1, and reducing the infiltration of inflammatory cells. FAM120A was identified as a key protein that activates the AMPK pathway, thus enhancing intestinal epithelial tight junction. Additionally, irisin was found to regulate the intestinal flora structure and potentially affect the migration of intestinal flora to the pancreas. These findings suggest that restoring intestinal barrier function through exercise-induced irisin may offer a novel therapeutic approach for T1DM. Display omitted
•Impaired irisin levels in new onset T1D patients and age-related decline in NOD mice, with LPS affects colon irisin expression, secretion, and barrier function.•Irisin Supplementation Delays Diabetes Onset in Female NOD Mice: This multifaceted intervention reduces insulitis, enhances energy expenditure, and ameliorates autoimmune manifestations. Exogenous irisin also induces changes in intestinal flora structure, mitigating the potential translocation of microorganisms from the intestine to the pancreas.•Harnessing irisin's exercise-mimicking properties suggests therapeutic potential in clinical settings for preventing T1D progression. This research offers valuable insights into fortifying the colon's intestinal barrier and managing autoimmune conditions associated with T1DM.
The incidence of papillary thyroid cancer (PTC) is increasing annually. ultrasonography (US) is the current primary method for evaluating thyroid nodules; however, there have been persisting ...challenges in diagnosing borderline malignancies. This paper aimed to establish the differential diagnostic value of salivary biomarkers for thyroid nodules geared towards improving the efficacy of US.
We recruited a total of 44 PTC patients and 42 benign thyroid tumor (BTT) patients to this study. The distribution of tumor markers and thyroid hormones in saliva and serum were compared between groups; then, uni-/multi-variate logistic analyses were used to determine the risk factors of PTC. Further, we estimated the differential diagnostic value of biomarkers in thyroid nodules, especially in borderline scenarios. Finally, a multi-index diagnostic model was constructed constituting biomarkers and US.
The distributions of serum thyroglobulin (TG), salivary triiodothyronine (T3), free-triiodothyronine (FT3), and free-thyroxine (FT4) were significantly different in BTT and PTC (P<0.05); salivary FT3 was identified as an independent risk factor for PTC. By analyzing the diagnostic accuracy of various Thyroid Imaging Reporting and Data System (TI-RADS) categories, category 4A was shown to have the lowest diagnostic accuracy (48.39%) with the largest proportion (31 people, 36.05%). In 4A patients, the K-nearest neighbor (KNN) algorithm attained the highest sensitivity of 87.50% and specificity of 100.00% among the machine learning-based multi-biomarkers models. Eventually, by combing the US with the KNN-based biomarkers model, the sensitivity and specificity reached 90.91% and 83.33%, respectively.
Salivary biomarkers exhibit good potential in the differential diagnosis of borderline thyroid nodules and they significantly improve the prediction accuracy of the US. Additionally, we found that salivary FT3 is an independent risk factor for PTC and may be used as a key marker for PTC diagnosis.
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