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Rational design of robust photocatalytic systems to direct capture and in-situ convert diluted CO 2 from flue gas is a promising but challenging way to achieve carbon neutrality. Here, we report a new type of host-guest photocatalysts by integrating CO 2 -enriching ionic liquids and photoactive metal-organic frameworks PCN-250-Fe 2 M (M = Fe, Co, Ni, Zn, Mn) for artificial photosynthetic diluted CO 2 reduction in gas-solid phase. As a result, [Emim]BF 4 (39.3 wt%)@PCN-250-Fe 2 Co exhibits a record high CO 2 -to-CO reduction rate of 313.34 μmol g −1 h −1 under pure CO 2 atmosphere and 153.42 μmol g −1 h −1 under diluted CO 2 (15%) with about 100% selectivity. In scaled-up experiments with 1.0 g catalyst and natural sunlight irradiation, the concentration of pure and diluted CO 2 (15%) could be significantly decreased to below 85% and 10%, respectively, indicating its industrial application potential. Further experiments and theoretical calculations reveal that ionic liquids not only benefit CO 2 enrichment, but also form synergistic effect with Co 2+ sites in PCN-250-Fe 2 Co, resulting in a significant reduction in Gibbs energy barrier during the rate-determining step of CO 2 -to-CO conversion. Artificial photosynthetic diluted CO 2 reduction from fuel gas is promising but challenging for carbon neutrality. Here, the authors report a host-guest system by integrating CO 2 -enriching ionic liquids and photoactive metal-organic frameworks, greatly enhancing CO 2 -to-CO conversion efficiency.

The oceans are natural sources of atmospheric methane (CH₄), but the origin of excess CH₄ at the surface remains enigmatic. Incubation experiments were conducted in the western North Pacific (WNP) and its marginal seas (i.e., Yellow Sea and South China Sea [SCS]) to identify the degradation of methylphosphonate (MPn) to CH₄ in the oceans and the microbes associated with MPn-driven CH₄ production. In the coastal seawater of the Yellow Sea, CH₄ was observed to accumulate after MPn enrichment with a high MPn to CH₄ conversion efficiency (approximately 60%). Dissolved inorganic phosphorus (Pi) did not effectively restrict the microbial utilization of MPn in the eutrophic coastal waters. The results of 16S rRNA gene sequencing showed that Vibrio spp. were the dominant bacteria in the MPn-amended treatments. Moreover, several Vibrio isolates isolated from the coastal waters were found to produce CH₄ while growing in culture using MPn as the sole P source, thereby indicating that Vibrio spp. might be the major contributors to MPn-dependent CH₄ production. In oligotrophic areas, such as the SCS and WNP, CH₄ production from MPn metabolism was also observed in the surface seawater. In contrast to coastal waters, this pathway in oligotrophic areas is regulated by dissolved Pi availability. This work confirms that aerobic CH₄ formation from MPn degradation can occur both in eutrophic coastal waters and oligotrophic oceans driven by MPn-utilizing microorganisms (especially heterotrophic bacteria), which may have a significant impact on our understanding of the CH₄ and P cycles in global oceans.

The Changjiang Estuary and its adjacent East China Sea are among the largest coastal hypoxic sites in the world. The oxygen depletion in the near-bottom waters (e.g., meters above the seabed) off the Changjiang Estuary is caused by water column respiration (WCR) and sedimentary oxygen respiration (SOR). It is essential to quantify the contributions of WCR and SOR to total apparent oxygen utilization (AOU) to understand the occurrence of hypoxia off the Changjiang Estuary. In this work, we analyzed the δ 18 O and O 2 /Ar values of marine dissolved gas samples collected during a field investigation in July 2018. We observed that the δ 18 O values of dissolved oxygen in near-bottom waters ranged from 1.039 to 8.457‰ (vs. air), generally higher than those of surface waters (−5.366 to 2.336‰). For all the sub-pycnocline samples, the δ 18 O values were negatively related to O 2 concentrations ( r 2 = 0.97), indicating apparent fractionation of δ 18 O during oxygen depletion in the water column. Based on two independent isotope fractionation models that quantified the isotopic distillation of dissolved oxygen concentration and its δ 18 O, the mean contributions of WCR and SOR to total near-bottom AOU were calculated as 53 and 47%, respectively. Beneath the pycnocline, the WCR contribution to the total AOU varied from 24 to 69%, and the SOR contribution varied from 31 to 76%. The pooled samples beneath both the pycnocline and upper mixed layer indicated that WCR contributions (%) to total AOU increased with increasing AOU (μmol/L), whereas SOR% – AOU had the reverse trend. We propose that the WCR% and SOR% contributions to the total AOU of the sub-pycnocline waters are dynamic, not stationary, with changes in ambient environmental factors. Under hypoxic conditions, we observed that up to 70% of the total AOU was contributed by WCR, indicating that WCR is the major oxygen consumption mechanism under hypoxia; that is, WCR plays a vital role in driving the dissolved oxygen to become hypoxic off the Changjiang Estuary.

Ocean circulations and water mass exchange can exert significant influences on seawater biogeochemistry, microbial communities, and carbon cycling in marine systems. However, the detailed mechanisms of the impacts of physical processes in the open ocean on the cycle of greenhouse gases, particularly methane, remain poorly understood. In this study, we integrated high-resolution underway observations, experimental incubations, radioisotope labelling, and molecular analysis to constrain the controls of methanogenic pathways, methanotrophic activity, and emission fluxes in the highly hydrodynamic Kuroshio and Oyashio Extension (KOE) region of the Northwest Pacific. The mixing of high-temperature, nutrient-rich Kuroshio waters with methane-rich Oyashio currents significantly affected not only methane abundance, but also methane production pathways and oxidation rates. Water mass mixing caused changes in the dominance of phytoplankton communities to Bacillariophyta, with less production of the methane precursor dimethylsulphoniopropionate, thus reducing dimethylsulphoniopropionate-dependent methanogenesis. The alteration of nutrient levels due to mixing of Kuroshio and Oyashio at KOE is also likely to affect microbial utilization of dissolved organic phosphorus, thus influencing methane production from the C−P cleavage of methylphosphonate. Furthermore, the abundances of methanotrophs, such as Methylocystis and Methylosinus, were much higher at the KOE sites than those observed at the Oyashio Extension, which contributed to elevated methane oxidation rates in the mixing region. Microbial oxidation as a biological sink of methane accounted for ~43.7% ± 28.8% of the total methane loss, which reduced methane emissions to the atmosphere. These data highlight the physical controls on biogeochemical methane cycling, indicating that intensive mixing of water masses may regulate methane emissions from the open oceans.

Large-scale climatic forcing is impacting oceanic biogeochemical cycles and is expected to influence the water-column distribution of trace gases, including methane and nitrous oxide. Our ability as a scientific community to evaluate changes in the water-column inventories of methane and nitrous oxide depends largely on our capacity to obtain robust and accurate concentration measurements that can be validated across different laboratory groups. This study represents the first formal international intercomparison of oceanic methane and nitrous oxide measurements whereby participating laboratories received batches of seawater samples from the subtropical Pacific Ocean and the Baltic Sea. Additionally, compressed gas standards from the same calibration scale were distributed to the majority of participating laboratories to improve the analytical accuracy of the gas measurements. The computations used by each laboratory to derive the dissolved gas concentrations were also evaluated for inconsistencies (e.g., pressure and temperature corrections, solubility constants). The results from the intercomparison and intercalibration provided invaluable insights into methane and nitrous oxide measurements. It was observed that analyses of seawater samples with the lowest concentrations of methane and nitrous oxide had the lowest precisions. In comparison, while the analytical precision for samples with the highest concentrations of trace gases was better, the variability between the different laboratories was higher: 36 % for methane and 27 % for nitrous oxide. In addition, the comparison of different batches of seawater samples with methane and nitrous oxide concentrations that ranged over an order of magnitude revealed the ramifications of different calibration procedures for each trace gas. Finally, this study builds upon the intercomparison results to develop recommendations for improving oceanic methane and nitrous oxide measurements, with the aim of precluding future analytical discrepancies between laboratories.

Gaseous phosphine (PH 3 ) in the inshore atmosphere was observed from October 2005 to August 2006 at a coastal site of the Yellow Sea in China. The concentration of PH 3 ranged from 0.01 to 14.86 ng m −3 with an average of 1.14 ng m −3 . The concentration showed a diurnal variation in PH 3 with the peak occurring at morning and the lowest point at noon. An obvious seasonal variation of atmospheric PH 3 was found, with the PH 3 levels in the summer higher than those in the winter. The PH 3 levels in the atmosphere were apparently affected by temperature, radiation, sources, and other meteorological factors. The data indicate that PH 3 can be transported between the terrestrial and inshore atmosphere of Qingdao and the Yellow Sea or the East China Sea in both directions. The study increases evidence that PH 3 participates within the global biogeochemical phosphorus cycle in P transport from land and inshore waters to the sea where commonly P is scarce and where PH 3 inflow could be of important.

Rational design of robust photocatalytic systems to direct capture and in-situ convert diluted CO from flue gas is a promising but challenging way to achieve carbon neutrality. Here, we report a new type of host-guest photocatalysts by integrating CO -enriching ionic liquids and photoactive metal-organic frameworks PCN-250-Fe M (M = Fe, Co, Ni, Zn, Mn) for artificial photosynthetic diluted CO reduction in gas-solid phase. As a result, [Emim]BF (39.3 wt%)@PCN-250-Fe Co exhibits a record high CO -to-CO reduction rate of 313.34 μmol g h under pure CO atmosphere and 153.42 μmol g h under diluted CO (15%) with about 100% selectivity. In scaled-up experiments with 1.0 g catalyst and natural sunlight irradiation, the concentration of pure and diluted CO (15%) could be significantly decreased to below 85% and 10%, respectively, indicating its industrial application potential. Further experiments and theoretical calculations reveal that ionic liquids not only benefit CO enrichment, but also form synergistic effect with Co sites in PCN-250-Fe Co, resulting in a significant reduction in Gibbs energy barrier during the rate-determining step of CO -to-CO conversion.

Background： The incidence of diabetic nephropathy （DN） increases year by year. However, clinical characteristics of DN patients on maintenance hemodialysis （MHD） were rarely reported in China. The purpose of this study was to examine the clinical characteristics of the DN patients on MHD in Anhui Province, Eastern China. Methods： The clinical data of MHD patients in the hemodialysis centers of 26 hospitals in Anhui Province from January 1, 2014, to March 31, 2014, were examined. The differences between DN patients and non-DN patients were compared regarding vascular access, nutritional status, mineral and boue disorder, and other indexes. Results： Among the selected 2768 adult MHD patients, 427 had DN. The incidence of hypertension, coronary heart disease, and cerebral thrombus in DN patients was 94.1%, 21.5%, and 15.0%, respectively, which were higher than those in non-DN patients （P 〈 0.001）. Category of vascular access for hemodialysis in DN patients was arteriovenous fistula （AVF） （87.4% [373/427]） and tunneled cuffed catheter （TCC） （11.2% [48/427]）. The percentage of AVF was significantly lower than that ofnon-DN patients （P 〈 0.001）, and percentage of TCC was significantly higher than that of non-DN patients （P 〈 0.001）. Hemoglobin achievement rate in DN patients was 32.0%. The incidence of hypoalbuminemia was 24.7%, significantly higher than that in non-DN patients （P 〈 0.001）. The achievement rate of the target range in mineral values was 55.9% in corrected serum calcium level, 30.1% in serum phosphorus level, and 49.3% in intact parathyroid hormone （iPTH） level in DN patients. Compared with non-DN patients, the achievement rate of serum phosphorus was significantly higher in DN patients. Conclusions： DN patients on MHD in Anhui province exhibited different clinical characteristics compared to non-DN hemodialysis patients. They presented higher percentage in TCC use and cardiovascular complication, lower serum albumin and iPTH levels than those in non-DN patients.

Despite its relatively low concentrations, short-lived CH4 in the atmosphere is approximately 25 times more effective on a per molecule basis than carbon dioxide (CO2) in trapping heat. [...]CH4 has a significant influence on global climate change, the oxidative capacity of the atmosphere, and the chemistry of the stratospheric ozone. Nitrous oxide (N2O) is a potent greenhouse gas in the atmosphere, and has a global warming potential of about 300 times that of carbon dioxide and a long atmospheric lifetime of 118 to 131 years (IPCC, 2013). [...]CH4 distribution is vertically uniform in the continental shelf zone in spring and winter. In the coastal seawaters of the YS, CH4 was observed to accumulate after MPn enrichment with high MPn-to-CH4-conversion efficiency (~60%). [...]several Vibrio isolates isolated from the coastal waters were found to produce CH4 while growing in culture using MPn as the sole phosphorus (P) source, thus indicating that Vibrio spp. are capable of cleaving MPn for P acquisition and might be the major contributors to MPn-dependent CH4 production ( Y e et al., 2020).

We have theoretically investigated two series of cyclometalated Pt(II) complexes, a series [Pt (C, N, N) Cl] and b series [Pt (C, N, N pyrazolyl ) Cl]. The geometrical and electronic structures are calculated at the ECP60MWB//6-31G*(H, C, Cl, N, S) basis set level using DFT method; one-photon absorption (OPA) properties are calculated by using both TDDFT and ZINDO methods and two-photon absorption (TPA) properties are obtained with the ZINDO/SOS method. The resonance integrals parameters ( β sp and β d ) for Pt are adjusted to −1 and −28.5 eV, respectively, to make max OPA wavelength calculated by ZINDO closest to the experimental data and TDDFT results. The calculated results indicate the molecule 2b ([Pt (C naphthyl , N, N pyrazolyl ) Cl]) has the biggest potential as outstanding TPA materials because (i) the TPA properties of b series are more outstanding in IR wavelength range, the molecules in b series have good transparencies and possess 1-pyrazolyl-NH that is also available for another metal coordination (e.g., dimerization) and chemical interactions; (ii) when C is C naphthyl in the C, N, N ligand of cyclometalated Pt(II) complexes, the molecules have the best conjugation effect and the best TPA properties.