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The dramatic increase in atmospheric CO2 concentrations has attracted people’s attention, and many strategies have been developed to convert CO2 into high-value chemicals. Metal-organic frameworks (MOFs), as a class of versatile materials, can be used in the CO2 capture and conversion because of their unique porosity, large specific surface area, rich pore structure, multiple active centers, good stability and recyclability. Various functional nanomaterials have been designed and synthesized based on metal organic framework (MOF) of crystalline porous materials to meet these challenges. Herein, in this review, the latest processes of MOFs in field the of CO2 hydrogenation to carbon monoxide, methane, formic acid, methanol and olefins are summarized, and the synthesis methods of catalysts based on MOFs and the reasons for their high catalytic activity are analyzed. Besides, a brief introduction to improve the catalytic activity of the new MOF material and explore the feasible strategies for CO2 conversion are advised. Finally, the paper discusses the main challenges and opportunities of MOF-type catalysts in CO2 chemical conversion, and presents a brief outlook on further developments in this research area.

The purpose of this meta-analysis was to evaluate the perioperative morbidity after anterior resection with diverting loop ileostomy (LI) versus colostomy (LC) and its reversal for rectal cancer. The studies on the application of loop ileostomy versus loop colostomy in anterior resection published from January 2000 to January 2020 were searched in the databases of Pubmed, Embase, Cochrane library, and Clinical trials. All randomized controlled trials (RCTs) and cohort studies were included according to inclusion criteria. Eight studies (2 RCTs and 6 cohort studies) totaling 1451 patients (821 LI and 630 LC) were included in the meta-analysis. The morbidity related to stoma formation and closure did not demonstrate significant differences. Significantly more LCs were complicated by stoma prolapseretraction (OR:0.26,95%CI:0.11-0.60,P = 0.001), parastomal hernia (OR = 0.52,95%CI:0.30-0.88, P = 0.01), surgical site infection (SSI) (OR = 0.24,95%CI:0.11-0.49,P 0.0001) and incisional hernias (OR = 0.39,95%CI:0.19-0.83,P = 0.01) than by LIs. Patients with LI demonstrated significantly more complications related to the stoma, such as dehydration (OR = 0.52,95%CI:0.30-0.88, P = 0.01) and ileus (OR = 2.23,95%CI:1.12-4.43, P = 0.02) than patients with LC. While after the subgroup analysis of different publication years, LI could reduce the risk of the morbidity after stoma formation in previous years group (P = 0.04) with a lower heterogeneity (I

Technology for the transformation of waste feathers to quality regenerated filaments has been developed. Regardless of superior properties of natural keratin materials, previously developed regenerated materials from keratin had tensile properties much lower than their natural counterparts due to backbone hydrolysis and inefficient reconstruction of disulfide crosslinkages. In this work, tough keratin filaments have been regenerated from white duck feathers via efficient restoration of disulfide crosslinkages using a dithiol reducing agent. Dithiol substantially reserves free thiol groups in the extraction and formed lengthy intermolecular crosslinkages in regenerated keratin filaments. Due to the high degree of intermolecular reconstruction of disulfide bonds and formation of lengthy crosslinkages via dithiol chain-extension, the keratin filaments exhibited considerable improvements in mechanical properties, especially for ductility and water stability. The tenacity and elongation at break were 160.7 MPa and 14%, respectively. The filaments retained about 80% of the tenacity of natural feathers at either dry or wet conditions and demonstrated stretchability 150% higher than natural feathers. The fiber regeneration technology makes it possible to substitute primary fiber sources by renewable poultry feathers. Successful filament substitution or addition can bring more than 88-billion-dollar revenue. The technology not only contributes to a sustainable fiber and poultry industry but adds substantial values to poultry feathers.

Objective: Antibiotic overuse is one of the major prescription problems in rural China and a major risk factor for antibiotic resistance. Low antibiotic prescription rates can effectively reduce the risk of antibiotic resistance. We hypothesized that under a paperless, computer-based feedback system the rates of antibiotic prescriptions among primary care physicians can be reduced. Methods: A cluster randomized crossover open controlled trial was conducted in 31 hospitals. These hospitals were randomly allocated to two groups to receive the intervention for three months followed by no intervention for three months in a random sequence. The feedback intervention information, which displayed the physicians’ antibiotic prescription rates and ranking, was updated every 10 days. The primary outcome was the 10-day antibiotic prescription rate of the physicians. Results: There were 82 physicians in group 1 (intervention first followed by control) and 81 in group 2 (control first followed by intervention). Baseline comparison showed no significant difference in antibiotic prescription rate between the two groups (30.8% vs 35.2%, P-value = 0.07). At the crossover point, the relative reduction in antibiotic prescription rate was significantly higher among physicians in the intervention group than in the control group (33.1% vs 20.3%, P-value

Polylactide/cellulose nanocomposites were fabricated by blending of commercial polylactide (PLA) and modified cellulose nanocrystals (CNCs). Modified CNCs were prepared via the in situ polymerization of CNCs and L-lactic acid (CNCs-PLLA) or D-lactic acid (CNCs-PDLA). The actual occurrence of chemical bond between CNCs and PLA segment was confirmed by Fourier transform infrared, nuclear magnetic resonance, X-ray diffraction and solubility tests. Differential scanning calorimetry and X-ray diffraction characterization indicated that CNCs-PDLA better improved the crystallization ability of PLA matrix compared with CNCs-PLLA. Furthermore, compared with the neat PLA (60.0 MPa), the tensile strength of resulting nanocomposites showed an enhancement of up to 36% (81.65 MPa). And the nanocomposites with CNCs-PDLA exhibited both high crystallinity and improved mechanical properties.

Abstarct Ferrous titanate (FeTiO3) nanoparticles with hexagonal disc structure were prepared by a simple hydrothermal method. The VSM results show that ferromagnetic-paramagnetic transition of FeTiO3 caused by high temperature hydrogenation. The morphology and lattice structure of FeTiO3 was characterized in detail by XRD, Raman, SEM and TEM. It was found that the magnetic transition of FeTiO3 nanoparticles after hydrogenation could be attributed to the change of lattice structure and surface effect. Further research by XPS found that the high temperature hydrogenation treatment could cause the change of elemental valence states and oxygen vacancies concentration for FeTiO3. The weakening of double exchange interaction (Fe2+-O-Fe3+) and the reduction of uncompensated surface spin were the main cause of the ferromagnetic-paramagnetic transition. This experiment would provide a new idea for regulating the magnetic property of materials.

A novel hydrogenated LaFeO3 was fabricated and firstly used as photocatalyst in the application of visible-light photocatalytic decomposition of organic contaminant. Through the adjusting of annealing atmosphere and temperature, a series of treated LaFeO3 with oxygen vacancies were obtained. Compared with untreated LaFeO3 and argon treated LaFeO3, hydrogenated LaFeO3 photocatalysts exhibited higher catalytic ability. This notably improved catalytic ability was mainly assigned to the formation of disordered layer on the surface of hydrogenated LaFeO3. The surface oxygen vacancies of LaFeO3 caused by hydrogenation were beneficial to light absorption and separation of photogenerated carriers. In this system, we found the amount of surface oxygen vacancies had a direct impact on the catalyst ability of hydrogenated LaFeO3 photocatalysts. In addition, the magnetic hydrogenated LaFeO3 photocatalysts were stable, and reused after five times without obvious decrease of catalytic ability.

A new strategy for the determination of bisphenol A (BPA) and diphenyl carbonate (DPC) in polycarbonate plastics has been proposed, combing excitation-emission matrix fluorescence and second-order chemometrics methods. The studied compounds are two of the most frequently used chemical raw materials and intermediates, which is mainly used for bio-chemical products. The method is fast and sensitive as it can avoid tedious pretreatment steps and large amounts of organic solvents consumption. Chemometrics allowed accurate and precise quantification of two target analytes even in the presence of severe spectral overlap, unknown and background interferences, which benefit from “second-order advantages” provided by chemometrics multivariate calibration. Reasonable quantification results were obtained in real plastics samples, with limits of detection for two analytes were 0.04 and 1.18 × 103 ng mL−1 and limits of quantitation were 0.11 and 3.58 × 103 ng mL−1. In addition, the average recoveries for BPA and DPC were 99.35% and 83.50% with relative standard deviation

The core-shell shaped Pt@CdS nanoparticles were successful anchored onto the surface of three-dimensionally ordered macroporous (3DOM) SrTiO3 with different pore sizes through a two-step photo-deposition method, to form a series of promising Z-scheme Pt@CdS/3DOM-SrTiO3 composites for photocatalytic hydrogen evolution from water splitting. The well-ordered inverse opal and ternary heterojunction structure of Pt@CdS/3DOM-SrTiO3 composites were well illustrated through SEM and HRTEM characterizations. The Pt@CdS/3DOM-SrTiO3 composites exhibited excellent efficiency for hydrogen evolution (57.9 mmol/g h) under UV–vis light irradiation. Through a series of controlled experiments and related characterizations, the notably enhanced catalytic performance of Pt@CdS/3DOM-SrTiO3 composites can be mainly attributed to the synergistic effect of the slow photon enhancement of 3DOM-SrTiO3, which significantly promotes the light harvesting efficiency of photocatalysts, and the enhanced separation of photogenerated carriers because of the Z-scheme charge transfer mechanism. In addition, the ternary Pt@CdS/3DOM-SrTiO3 catalysts are very stable and can be recycled five times without any decrease in photocatalytic activity.

In this work, a simple and effective strategy for the determination of 12 active compounds of Atractylodes macrocephala Koidz. (AM) was proposed by using high performance liquid chromatography-diode array detection (HPLC-DAD) combined with alternating trilinear decomposition (ATLD) algorithm. Utilizing the "second-order advantage", three common problems in HPLC could be resolved, namely baseline drifts, peak overlaps, and unknown interferences. 12 compounds were rapidly eluted within 12.5 min, and the average spiked recoveries were 80.8-109.9%. The figures of merit reflected the feasibility of the proposed method. Compared with the results of the traditional univariate calibration method based on HPLC-UV technique, the proposed strategy further verified the reliability and simplicity of the mathematical separation. On this basis, partial least squares-discriminant analysis (PLS-DA) was applied to discriminate 113 AM samples from different geographical origins, and variable importance in projection (VIP) was used to further screen the main differential components that affect the regional division of AM. A series of results show that the AM samples from the three regions have obviously different clustering trends. Overall, the strategy is expected to provide a scientific basis for the modern research of medicinal materials, and it is also conducive to the clinical use and market supervision of AM.

The surface urban heat island (SUHI) phenomenon is characterized by both high spatial and temporal variability, while its diurnal (i.e., diel) variations have rarely been investigated because traditional satellites and sensors flying on polar orbits (e.g., Landsat, MODIS) have no diurnal sampling capability. Here we combined land surface temperature (LST) data from the Geostationary Operational Environmental Satellites (GOES-R) and the Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) to explore the diurnal variations of SUHI and thermal differentiation among various land covers over the Boston Metropolitan Area. With the combined use of the LST data from GOES-R and ECOSTRESS, we took advantage of the strengths of both GOES-R (i.e., high frequency in each day and night) and ECOSTRESS (i.e., much finer spatial resolution). The SUHI intensity of the urban-core and suburban areas both exhibited clear diurnal patterns for different seasons: a continuous increase in the SUHI intensity from sunrise to noon and a decrease thereafter to sunset, followed by a relatively low and constant intensity during nighttime. The LST contrasts among different land cover types were clearly larger in the daytime than at nighttime and peaked around midday. At noon in summer, the LST of 'Developed, High Intensity' was 2.6 °C higher than that of 'Developed, Medium Intensity', and about 4.6 °C higher than that of "Developed, Open Space" and "Developed, Low Intensity". Controlling the percent impervious surface in construction land at a relatively low level (e.g., below ~49%) could effectively alleviate the impacts of SUHI. Compared with GOES-R data, ECOSTRESS LST is suitable for monitoring the diurnal variations of intracity thermal environment at the subdistrict (or neighborhood) scale. Our study highlights the value of the combined use of geostationary satellite and ECOSTRESS LST in exploring the diurnal cycling of the SUHI, and can help inform urban planning and land-based climate mitigation policies in the context of climate change.

Southern Shaanxi is located in one of the water sources of the China's South-to-North Water Diversion Project. Evaluating ecological vulnerability can effectively supervise environmental changes and master evolving driving forces so as to guide the rational use and protection of ecological environment in regional water sources. Based on meteorological data, remote sensing images and statistical data, this study established an evaluation index system for ecological vulnerability in this special area. Taking advantage of visual expression and data mining capacity of geographical information system and remote sensing, a spatial principal component analysis method was introduced to evaluate the geospatial and temporal features of ecological vulnerability. This study established a feasible method to comprehensively assess the level of ecological vulnerability, and quantitatively analyze the driving forces that affected the ecological vulnerability in study area. The results indicated high levels of ecological vulnerability grade in the urban areas and the adjacent counties. With the accelerated urbanization, the ecological vulnerability index of the three major urban areas and their surrounding areas had gradually increasing ecological vulnerability index. The proportion of III vulnerable areas was always the largest area, which also led to an increase in the instability of the ecological environment. Over time, the most important driving force for ecological vulnerability of evaluation units in different regions was socio-economic factors, and environmental topographic factors were also important secondary factors for ecological vulnerability in Southern Shaanxi.

In this study, a n-type semiconductor perylene diimide (PDI) was coupled with biodegradation to accelerate the biotic decolorization and mineralization of methyl orange (MO) under light condition. The decolorization rates (k1) of MO in pure and mixed cultures with PDI were promoted by 1.35 and 1.79 folds, respectively, comparing to the cultures without PDI. The total mineralization efficiency of 4-aminobenzenesulfonic acid (4-ABA) was achieved to 22.10 ± 0.84% when in the presence of PDI. The quinone-like group and oxidation-reduction capacity of PDI were detected by Fourier transform infrared spectroscopy and cyclic voltammetry, respectively, but the enhancement on the biotic decolorization of MO was not promoted under dark condition indicating that microbial extracellular electron transfer was not promoted. The 4-ABA was confirmed to be partially mineralized when the PDI exposure to light. The generated free radicals i.e., h+, ⸱OH, was demonstrated as active species to accelerate the decolorization and mineralization of MO by ESR test and radical quenching experiments. The bond breaking of MO and 4-ABA molecules were successfully predicted by density functional theory calculations and were further proven by liquid-chromatography mass spectra. The synergistic mechanism of decolorization and mineralization of MO by microorganism and photocatalysis was proposed. Moreover, High-throughput sequencing and Live/dead cell results indicated that the presence of PDI has no obvious toxicity to the microorganisms and will not change the microbial communities during the short-term treatment period. The results of study provided a biological intimate photocatalytic material and suggested a feasible way for its combination with biodegradation of azo dyes.

Cu Zn oxide/SAPO-34 molecular sieves was used as bifunctional catalyst for the direct synthesis of light olefins from CO2 and H2, but the production of SAPO-34 molecular sieves required high cost and the Cu Zn oxide (CuO-ZnO) particles were prone to sintering, which severely restricted its industrial application. Herein, kaolin was used as raw material to prepare SAPO-34 molecular sieves and as supports to prepare kaolin-supported CuO-ZnO catalysts. The samples were characterized by X-ray diffraction, Scanning Electron Microscope, Energy Dispersive Spectroscopy, N2 sorption, H2 temperature programmed reduction, NH3 temperature programmed desorption and Fourier Transforms Infrared spectra techniques. The results showed that the SAPO-34 molecular sieves presented lamellar structure and the CuO-ZnO particles were well dispersed on the surface of kaolin. The results of catalytic reaction for the direct synthesis of light olefins from CO2 and H2 indicated that the (CuO-ZnO)-kaolin/SAPO-34 molecular sieves could enhance not only the yield of light olefins, but also the lifetime.

Novel hierarchical MCM-68 zeolite materials were successfully prepared by two simple, effective and environmentally friendly methods: H2O2 microexplosion under microwave and NH3(aq) treatment. The characterization of the materials with powder XRD, SEM, TEM, N2-sorption, and NH3-TPD proved that abundant mesopores across zeolite crystals were created while the microporous MSE framework was well preserved. The mesopore volume of hierarchical MCM-68 zeolites is up to 0.19 cm3 g−1. The crystallinities of hierarchical ones and microporous MCM-68 are nearly the same according to the XRD result. The acidities of hierarchical MCM-68 are generally lower than their raw materials. Gas-phase isomerization reaction of m-xylene was carried out over these hierarchical MCM-68 zeolites as well as HMCM-68 zeolite under different conditions to characterize the catalytic property of newly prepared hierarchical zeolites. It was found that the m-xylene conversion and disproportionation/isomerization rate ratio were closely related to the created mesopores in hierarchical MCM-68 zeolites under high reaction temperature and low weight hourly space velocity (WHSV). Moreover, these hierarchical MCM-68 zeolites exhibited improved resistance to coke formation compared with HMCM-68.