Breaking The Permeance-Selectivity Tradeoff for Post-Combustion Carbon Capture: A Bio-Inspired Strategy to Form Ultrathin Hollow Fiber Membranes.

Thin film composite (TFC) hollow fiber membranes with ultrathin selective layer are desirable to maximize the gas permeance for practical applications. Herein, a bio-inspired strategy is proposed to fabricate sub-100-nm membranes via a tree-mimicking polymer network with amphipathic components featuring multifunctionalities. The hydrophobic polydimethylsiloxane (PDMS) brushes act as the roots that can strongly cling to the gutter layer, the PDMS crosslinkers function as the xylems to enable fast gas transport, and the hydrophilic ethylene-oxide moieties (brushes and mobile molecules) resemble tree leaves that selectively attract CO2 molecules. As a result, a ≈27 nm-thick selective layer can be attached to the hollow fiber-supported PDMS gutter layer through a simple dip-coating method without any modification. Furthermore, a CO2 permeance of ≈2700 GPU and a CO2 /N2 selectivity of ≈21 that is beyond the permeance-selectivity upper bound for hollow fiber membranes is achieved. This bio-inspired concept can potentially open the possibility of scalable hollow fiber membranes production for commercial applications in post-combustion carbon capture and beyond.

Tunable Supramolecular Cavities Molecularly Homogenized in Polymer Membranes for Ultraefficient Precombustion CO2 Capture.

Processable molecular-sieving membranes are important materials for realizing energy-efficient precombustion CO2 capture during industrial-scale hydrogen production. However, the promising design of mixed matrix membranes (MMMs) that aims to integrate the molecular-sieving properties of nanoporous architectures with industrial processable polymers still faces performance and fabrication issues due to the formation of segregated nanofiller domains in their polymer matrices. Here, an unconventional nanocomposite membrane design is proposed using soluble organic macrocyclic cavitands (OMCs) with tunable open cavity sizes that not only mitigate the formation the discrete nanofiller phases but also deliver distinct molecular-sieving separations. The versatile organic-solvent solubility coupled with highly interactive functionalities of OMCs allows them to obtain molecularly homogeneous mixing with matrix polymers and form only one integral continuous phase crucial to the robust processability of polymers. A series of polybenzimidazole-based molecularly mixed composite membranes (MMCMs) are fabricated via the incorporation of a soluble and thermally stable OMC choice, sulfocalixarenes, with various cavity sizes. These membranes achieve outstanding high-temperature mixed-gas H2 /CO2 separation performances comparable with several state-of-the-art molecular-sieving membranes owing to effective size-sieving gas passages through the open or partially-intruded supramolecular cavities. The broadly tunable structures and functionalities of OMCs would make their MMCMs attractive for other energy-intensive molecular separations.

Novel Cellulose Triacetate (CTA)/Cellulose Diacetate (CDA) Blend Membranes Enhanced by Amine Functionalized ZIF-8 for CO2 Separation.

Currently, cellulose acetate (CA) membranes dominate membrane-based CO2 separation for natural gas purification due to their economical and green nature. However, their lower CO2 permeability and ease of plasticization are the drawbacks. To overcome these weaknesses, we have developed high-performance mixed matrix membranes (MMMs) consisting of cellulose triacetate (CTA), cellulose diacetate (CDA), and amine functionalized zeolitic imidazolate frameworks (NH2-ZIF-8) for CO2 separation. The NH2-ZIF-8 was chosen as a filler because (1) its pore size is between the kinetic diameters of CO2 and CH4 and (2) the NH2 groups attached on the surface of NH2-ZIF-8 have good affinity with CO2 molecules. The incorporation of NH2-ZIF-8 in the CTA/CDA blend matrix improved both the gas separation performance and plasticization resistance. The optimized membrane containing 15 wt.% of NH2-ZIF-8 had a CO2 permeability of 11.33 Barrer at 35 °C under the trans-membrane pressure of 5 bar. This is 2-fold higher than the pristine membrane, while showing a superior CO2/CH4 selectivity of 33. In addition, the former had 106% higher CO2 plasticization resistance of up to about 21 bar and an impressive mixed gas CO2/CH4 selectivity of about 40. Therefore, the newly fabricated MMMs based on the CTA/CDA blend may have great potential for CO2 separation in the natural gas industry.

Polyphenylsulfone (PPSU)-Based Copolymeric Membranes: Effects of Chemical Structure and Content on Gas Permeation and Separation.

Although various polymer membrane materials have been applied to gas separation, there is a trade-off relationship between permeability and selectivity, limiting their wider applications. In this paper, the relationship between the gas permeation behavior of polyphenylsulfone(PPSU)-based materials and their chemical structure for gas separation has been systematically investigated. A PPSU homopolymer and three kinds of 3,3',5,5'-tetramethyl-4,4'-biphenol (TMBP)-based polyphenylsulfone (TMPPSf) copolymers were synthesized by controlling the TMBP content. As the TMPPSf content increases, the inter-molecular chain distance (or d-spacing value) increases. Data from positron annihilation life-time spectroscopy (PALS) indicate the copolymer with a higher TMPPSf content has a larger fractional free volume (FFV). The logarithm of their O2, N2, CO2, and CH4 permeability was found to increase linearly with an increase in TMPPSf content but decrease linearly with increasing 1/FFV. The enhanced permeability results from the increases in both sorption coefficient and gas diffusivity of copolymers. Interestingly, the gas permeability increases while the selectivity stays stable due to the presence of methyl groups in TMPPSf, which not only increases the free volume but also rigidifies the polymer chains. This study may provide a new strategy to break the trade-off law and increase the permeability of polymer materials largely.

Ultra-strong polymeric hollow fiber membranes for saline dewatering and desalination.

Osmotically assisted reverse osmosis (OARO) has become an emerging membrane technology to tackle the limitations of a reverse osmosis (RO) process for water desalination. A strong membrane that can withstand a high hydraulic pressure is crucial for the OARO process. Here, we develop ultra-strong polymeric thin film composite (TFC) hollow fiber membranes with exceptionally high hydraulic burst pressures of up to 110 bar, while maintaining high pure water permeance of around 3 litre/(m2 h bar) and a NaCl rejection of about 98%. The ultra-strong TFC hollow fiber membranes are achieved mainly by tuning the concentration of the host polymer in spinning dopes and engineering the fiber dimension and morphology. The optimal TFC membranes display promising water permeance under the OR and OARO operation modes. This work may shed new light on the fabrication of ultra-strong TFC hollow fiber membranes for water treatments and desalination.

Ultrahigh Flux Composite Hollow Fiber Membrane via Highly Crosslinked PDMS for Recovery of Hydrocarbons: Propane and Propene.

In order to make membrane separation technologies more cost-competitive with the well-established processes that are energy intensive for gas/vapor separation, a defect-free membrane with a high gas permeance is necessary. However, it remains challenging to meet these needs because of the difficulties in developing a suitable material and process that are economical and practical. Herein, a novel and straightforward strategy is presented to produce a defect-free hollow fiber composite membrane using a highly crosslinked polydimethylsiloxane (PDMS) synthesized by using a postcrosslinking method. The PDMS can be directly coated on a polyacrylonitrile (PAN) membrane substrate, and the resultant PDMS/PAN composite membrane has ultrahigh C3 H8 and C3 H6 permeances that are higher than 10 000 and 11 000 GPU, respectively, and the corresponding permselectivity of C3 H8 /N2 and C3 H6 /N2 are about 21 and 24, respectively. The newly developed methods and materials may open up a new cost-effective method to fabricate next-generation composite membranes for the recovery of hydrocarbons, organic vapors, and gases.

Combination of forward osmosis (FO) process with coagulation/flocculation (CF) for potential treatment of textile wastewater.

A novel combination of forward osmosis (FO) process with coagulation/flocculation (CF) (FO-CF) has been experimentally conceived for the treatment and reuse of textile wastewater. FO is employed to spontaneously recover water from the wastewater via osmosis and thus effectively reduces its volume with a dramatically enhanced dye concentration. CF is then applied to precipitate and remove dyes from the FO concentrated stream with much improved efficiency and reduced chemical dosage. The FO-CF hybrid system exhibits unique advantages of high water flux and recovery rate, well controlled membrane fouling, high efficiency, and minimal environmental impact. Using a lab-made thin-film composite (TFC) FO membrane, an initial water flux (Jw) of 36.0 L m(-2) h(-1) with a dye rejection of 99.9% has been demonstrated by using 2 M NaCl as the draw solution and synthetic textile wastewater containing multiple textile dyes, inorganic salts and organic additives as the feed under the FO mode. The Jw could be maintained at a high value of 12.0 L m(-2) h(-1) even when the recovery rate of the wastewater reaches 90%. Remarkable reverse fouling behavior has also been observed where the Jw of the fouled membrane can be almost fully restored to the initial value by physical flushing without using any chemicals. Due to the great dye concentration in the FO concentrated wastewater stream, the CF process could achieve more than 95% dye removal with a small dosage of coagulants and flocculants at 500-1000 ppm. The newly developed FO-CF hybrid process may open up new exploration of alternative technologies for the effective treatment and reuse of textile effluents.

Discuss the SOP in the application of the administration and operation of instruments / 中国实用护理杂志

Objective To standardize the operation processes of neonatal instrument,ensure the standards effectiveness and safety of equipment use.Methods A retrospective study had been taken on after the developments and implementations of all neonatal instruments standard operation procedure (SOP).The equipment maintenance data were collected and analyzed one year before and after the implementation of SOP.Results After the effective implementation of the SOP,the incidence of instrument repair due to misoperation,improper maintenance reduad by 59％(19/32),9/14,4/7,the instrument management efficiency was enhanced,and the safety of nurses and patients was guaranteed,and the patients satisfaction was improved,and also the quality of care was enhanced.Conclusions SOP procedure plays a very important role in improving neonatal care management and overall efficiency.It makes a continuous improvement of nursing care which is worth widely being implemented.

Survey of smoking behaviors among male smokers in two districts of Chengdu / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the smoking behaviors and its influencing factors among male smokers in two districts in Chengdu.</p><p><b>METHODS</b>A face to face questionnaire survey was conducted among 320 male smokers in Chengdu. And the data were analyzed with descriptive epidemiological method, t test, χ2 test, one-way analysis of variance, Kruskal-Wails H rank sum test and cumulative odds logistic regression model.</p><p><b>RESULTS</b>More cigarette smoking (t=2.327, P=0.021) and using cigarette with lower tar level (t=-11.251, P<0.001) after changing the brand of cigarette were found among the males surveyed. The cumulative odds logistic regression analysis showed that males with lower education level (OR=1.968, P=0.040), with higher income level (OR=2.053, P=0.043), leaving shorter butts (OR=2.366, P=0.010) and with high nicotine dependence (OR=7.143, P<0.001) had more cigarette smoking.</p><p><b>CONCLUSION</b>Smokers who changed the brand of cigarette were more likely to choose low tar cigarette. Smokers with low education level, high income level and high nicotine dependence are the target population for health education and behavior intervention in smoking control.</p>

Expression and activity of glycosylphosphatidylinositol-specific phospholipase d mRNA in bone marrow mononuclear cells isolated from patient with acute myeloid leukemia and their significance / 中国实验血液学杂志

This study was purposed to investigate the expression and significance of glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) in bone marrow mononuclear cells (BMMNC) isolated from patients with acute myeloid leukemia (AML), GPI-PLD activity in BMMNC isolated from 78 patients with AML and 15 normal persons was measured by using GPI-anchored placental alkaline phosphatase (PLAP) as a substrate and Triton X-114 phase partitioning. The GPI-PLD mRNA expression was measured by semi-quantitive reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the mRNA expression level and activity of GPI-PLD in BMMNC from de novo AML patients were 1.86 +/- 0.32 and 46.96 +/- 7.15% respectively; the mRNA expression level and activity of GPI-PLD in BMMNC from completely remission and refractory or relapsed patients were 1.26 +/- 0.29, 33.36 +/- 5.13%and 1.79 +/- 0.19, 44.31 +/- 7.22%, while those in BMMNC from normal controls were 1.27 +/- 0.23, 35.38 +/- 5.15% respectively. The mRNA expression level and activity of GPI-PLD in de novo and refractory or relapsed patients were obviously higher than those in normal controls with significant difference (p < 0.01), while the comparison between remitted patients and normal controls showed no statistical difference (p > 0.05). It is concluded that the expression level of GPI-PLD mRNA coincides with GPI-PLD activity. The mRNA expression and activity of GPI-PLD in de novo and refractory or relapsed patients are obviously higher than those in normal controls. It is worthy of further exploring whether GPI-PLD plays a certain role in process of leukemia pathogenesis.