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Nanofiltration performance at high temperatures was examined using SiO 2 -ZrO 2 membranes fired at 200 and 550 °C. After SiO 2 -ZrO 2 membranes were treated in water at 90 °C for 4 h, the water permeability ( L p ) at 25 °C for both membranes increased approximately 3-fold and remained constant for as long as 100 h treatment, indicating stability in aqueous solutions as high as 90 °C. The increase in water permeability of membrane was ascribed to increased hydrophilicity and dissolution of silica into water at 90 °C. Molecular weight cut-offs (MWCOs) for SiO 2 -ZrO 2 membrane fired at 550 °C did not change with treatment time (MWCOs = 300) while the MWCOs for SiO 2 -ZrO 2 membrane fired at 200 °C increased from 240 to 300. SiO 2 -ZrO 2 membranes fired at 550 °C showed higher hydrothermal stability than those fired at 200 °C. The effect of temperature on SiO 2 -ZrO 2 membrane performance was evaluated for nanofiltration at temperatures range of 25–90 °C. The rejection of glucose and maltose decreased with an increase in temperature for SiO 2 -ZrO 2 membranes both fired at 200 and 550 °C, while the permeate flux increased. On the other hand, the temperature has no influence on rejection of raffinose, which was always larger than 95%.

Organosilica microporous membranes were fabricated from 1, 2-bis (triethoxysilyl) ethane (BTESE)-derived sols prepared in acidic pH via the pH-swing method. This method includes two steps whereby a specific amount of NH3 was added into the acid sols and switched to acid after a reaction of several minutes. We found that the size of the BTESE-derived sols by pH-swing could be controlled via the H2O/BTESE molar ratio and the reaction time in alkali. Under the same H2O/BTESE ratio of 60, the BTESE-derived sols prepared in the pH-swing method showed an increase sol size in contrast with the acid method, and the sol size was easily controlled by the dominating reaction in alkali pH – the condensation reaction. Gas permeation results showed that some gases (He, H2, N2, C3H8, SF6) permeated the membrane that was prepared using the pH-swing sols (pH-swing membrane) at approximately twice the rate shown by the membrane prepared using acid sols (acid membrane); H2 permeance levels of the pH-swing membrane and the acid membrane were 3.4×10−6 and 1.6×10−6 mol m−2 s−1 Pa−1 at 200 °C, respectively. The pH-swing membrane also maintained similar H2/C3H8 permeance ratios of ranging from 2600~5800, confirming that pH-swing processing is an innovative method for improvement in the gas permeance of BTESE-derived organosilica membranes. One possible reason for these results could be that the membranes prepared using the pH-swing sols increased the size of the sols, which reduced the sol penetration into the intermediate layer. Moreover, the high cross-linking that was caused by pH-swing increased the thermostability of the BTESE-derived organosilica networks. The CO2/CH4 and CO2/N2 permeance ratios for the pH-swing membrane were as high as 90 and 28, respectively, at 50 °C.

The fluorine doping of a silica matrix was proposed in the design of enlarged and uniform networks for highly permeable CO2/CH4 separation membranes. Fluorine doping effectively created a tunable network size, and the order of pore sizes increased with increases in the F concentration: F−SiO2 (F/Si=2/8)>F−SiO2 (F/Si=1/9)>SiO2. F−SiO2 (F/Si=1/9) membranes showed high CO2 permeance (4.1×10−7 mol m−2 s−1 Pa−1) with high CO2/CH4 selectivity (≈300) at 35 °C, due to the enlarged and uniform networks compared with those of SiO2. Fluorine doping was effective in preventing the formation of a 2nd Si−O in the 4-membered ring (MR) of the SiO4 tetrahedra. F−SiO2 samples with smaller fractions of 4 MR and a smaller ring in silica, contain large fractions of larger rings (>5 MR), resulting in enlarged network structure and an increase in the average pore size, which translates to a higher permeance for larger molecules.

SiO 2 –ZrO 2 membranes were successfully prepared by coating SiO 2 –ZrO 2 (molar ratio 5/5) sols on cylindrical α-alumina porous supports with average pore sizes of 2.1, 2.9 and 3.6 μm followed by firing at 550 °C. The pore sizes of the SiO 2 –ZrO 2 membranes, which were evaluated by nanopermporometry using hexane, were 1.20 and 0.65 nm after coating with SiO 2 –ZrO 2 sols of 35 and 19 nm in diameter, respectively. The membrane pore sizes were not affected by the pores of the supports, but, instead, were controlled by the colloidal sizes of the SiO 2 –ZrO 2 sols that made up the top layer. The average pore sizes of SiO 2 –ZrO 2 membranes fired at 200, 300, 400 and 550 °C increased slightly from 0.60 to 0.70 nm with an increase in the firing temperature while water permeability ( L p ) tended to decrease with increases in the firing temperature that ranged from (3.3–0.8)×10 −12 m 3 /(m 2 s Pa). The decreased water permeability was ascribed to chemical and physical changes by firing temperature such as hydrophilicity/hydrophobicity, porosity, etc. The water permeabilities of SiO 2 –ZrO 2 membranes showed stable flux due to the addition of zirconia into the silica sol, showing improved stability in water. Nanofiltration performance was evaluated using aqueous solutions and showed molecular weight cut-offs ranging from 200 to 350.

Amorphous carbon membranes were successfully synthesized onto a SiO2–ZrO2/α-Al2O3 nanoporous substrate via plasma-enhanced chemical vapor deposition (PECVD) at room temperature. PECVD-derived amorphous carbon membranes exhibited molecular sieving properties, showing ideal selectivities of 23 and 1750 for He/N2 and He/SF6, respectively, at 25 °C. The membrane maintained high selectivity even at high temperatures as high as 200 °C, indicating considerable stability of the plasma-deposited amorphous carbon layer.

Bis(triethocysilyl)ethane (BTESE)-derived organosilica membranes were applied for the dehydration of aqueous isopropanol (IPA) solutions in pervaporation and vapor permeation. The stability of the membranes under high-water-content systems was demonstrated in pervaporation and vapor permeation. The membranes showed excellent stability in the long-term pervaporation of a 50 wt% IPA aqueous solution at 75 °C. The membranes were also stable in vapor permeation with a high-water-content stream (IPA concentration of 50 wt%) at 100 °C. These results clearly demonstrated that BTESE-derived organosilica membranes are applicable for the dehydration of high-water-content mixtures. The effect of the feed component and operating temperature on dehydration performance was also investigated. An analysis of the permeation resistance through the membranes was conducted based on a simple series-resistance modeling approach and revealed that the permeation resistance of the support layer strongly inhibited the water permeability, particularly when the water content in the feed was high.

The evolution of the physicochemical properties of allylhydridopolycarbosilane (AHPCS) was systematically investigated via DLS, TG, FTIR, XRD, and EDS. AHPCS-derived membranes were prepared by coating AHPCS sols onto porous substrates, which was then followed by pyrolysis at 300–800 °C. The pre-crosslinking by thermal curing significantly increased the colloidal sol size of AHPCS in toluene solutions, which effectively reduced penetration into substrates and enhanced the gas permeation. Furthermore, the pore structure of AHPCS-derived membranes could be precisely tailored by the pyrolysis temperatures, and the results indicated that the structure of membranes could be roughly classified into one of three types: a dense polymer structure, a loose transitional structure, and a denser ceramic structure (here, the term ‘dense/denser’ refers to the small/smaller pore structure, while the ‘loose’ refers to the large pore structure). AHPCS-derived membranes prepared at 300–800 °C under a N2 flow displayed superior H2 permeance of (0.2–5) × 10−6 mol/(m2 s Pa) at 200 °C with good H2/N2 selectivity of 12–56. Ceramic SiC membranes prepared at 700 °C showed an attractive H2 permeance of (2–4) × 10−6 mol (m2 s Pa)−1 at 200 °C with H2/N2 selectivity of 16–22, H2/SF6 selectivity higher than 10,000, and N2/SF6 selectivity higher than 800. Moreover, the structure of the ceramic SiC membranes was highly stable with good oxidation resistance at 500 °C under air. AHPCS membranes prepared at 300–800 °C had different pore structures that exhibited a high level of quality and a variety of permeation properties that could provide many options for membrane materials over a wide range of applications.

In this study, the physicochemical properties and microstructural variations of polycarbosilane (PCS) were systematically investigated at curing temperatures of 150–350 °C and pyrolysis temperatures of 350–850 °C. Oxidative cross-linking remarkably enhanced the thermal stability of the PCS structure. Elemental composition and microstructure of the final ceramic material could be precisely tailored via the air curing process. Cross-linking by air curing that is either excessive or insufficient could cause the micropores of the resulting ceramic material to collapse or disappear. The most promising PCS-derived membranes, which were cured at 250 °C and then pyrolyzed at 750 °C, had high thermal stability and oxidation resistance at 500 °C in addition to excellent permeation properties: H2 permeance of 1–2 × 10−6 mol/(m2 s Pa) at 500 °C with H2/N2 selectivity of 31 and H2/C3H8 selectivity of 1,740; and, CO2 permeance of 1.8 × 10−6 mol/(m2 s Pa) at 27 °C with CO2/CH4 selectivity of 40. Moreover, permeance and selectivity in an equimolar H2/C3H8 mixture at 500 °C were approximately the same as those in single gases, suggesting the separation mechanism could be ascribed to molecular sieving. This is the first study to propose the concept of tailoring the microstructure of SiC-based membranes by controlling the curing process.

Al2O3 nanoporous membranes for nanofiltration were successfully prepared from nanofiber sols (4 nm in diameter and 1400 nm in length) by controlling the number of sol coats and the firing temperature of the membrane. The effects of the number of sol coats and the firing temperature were characterized via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption, scanning electron microscope (SEM), transmission electron microscopy (TEM), nanopermporometry, and nanofiltration. A crack-free and continuous separation layer of the membranes, which is composed of Al2O3 nanofibers overlapping in the same direction on the membrane surface, was achieved. A greater number of sol coats greatly reduced the N2 permeance and water permeability of the membrane, but had no significant effect on either the average pore size or the molecular weight cut-off (MWCO). Meanwhile, firing temperature greatly affected the structure and separation performance of the membranes due to a transformation of the crystalline phase from boehmite to γ-Al2O3 under high temperatures. Al2O3 nanofiber-derived membranes had an average pore size and a MWCO that tended to be constant at 1.0 nm and 870–990 g/mol via firing at 200 °C, irrespective of the number of sol coats. Those values were increased, however, with increases in the firing temperature.

Membrane-based separation technologies are considered an effective process for the capture of CO2 due to advantages such as high levels of energy efficiency with inexpensive levels of investment. It remains challenging, however, to develop a membrane with high levels of both permeance and selectivity with the ability to capture CO2 in a highly efficient manner. Herein, we report amino-decorated organosilica membranes that are based on a facile and effective co-polymerization strategy that uses bis(triethoxysilyl)acetylene (BTESA) and (3-aminopropyl) triethoxysilane (APTES) precursors. This co-polymerization strategy simultaneously endows the resultant membranes with a controlled pore size and enhanced CO2-philic properties that have significantly improved CO2 separation performance. These composite membranes display CO2 permeance that ranges from 2550–3230 GPU and a range for CO2/N2 selectivity of 31–42 in the separation of CO2/N2 mixtures, which outperforms most state-of-the-art membranes and exceeds the target for post-combustion CO2 capture operations. A satisfying performance was achieved with a CO2 permeance of 8 ✕ 10−7 mol m−2 s−1 Pa−1 (2390 GPU) and CO2/CH4 selectivity of 70. The present study highlights an elegant decoration strategy for the production of membranes with ultrahigh CO2 capture capacities, which can also be extended to other organosilica precursors for target-oriented separations by varying the bridged or side-chain groups.

Membrane-based separation of organic/organic mixtures is of great importance in the chemical and petrochemical industries, but remains very challenging owing to the harsh working conditions. Herein, ultrathin and chemically stable Bis(triethoxysilyl)acetylene (BTESA)-derived organosilica membranes were reproducibly prepared, and for the first time they were utilized in the pervaporation separation of methanol/organic azeotropes. The as-prepared BTESA membranes exhibited exceptional pervaporation performance in a 10 wt%/90 wt% methanol/dimethyl carbonate (DMC) mixture, and showed a high separation factor of approximately 120 with a permeation flux of 2–4 kg m-2 h-1 at 50 °C. This impressive performance was primarily the result of the preferential sorption of methanol and the efficient size sieving of DMC. In addition, the effects of feed concentration and temperature on methanol/DMC pervaporation performance were thoroughly investigated. Importantly, a generalized solution-diffusion model successfully described the pervaporation performance of BTESA membranes, and the usefulness of this model was further confirmed via the pervaporation of methanol/methyl acetate and methanol/methyl tert-butyl ether (MTBE) mixtures. This work demonstrates the great potential of organosilica membranes for high-performance organic/organic pervaporation.

The management of oily wastewater produced in the petrochemical industries poses an immense challenge from both practical and environmental points of view. Filtration using ceramic membranes has been considered a promising technology to remove stable emulsions from oily wastewater; however, the separation performances are severely limited by membrane fouling. In this study, we evaluated the filtration performance of porous ceramic membranes for the treatment of oil/water emulsions. Porous ceramic membrane, having different pore sizes (0.1–1.4 μm) and made from various materials (Al2O3, TiO2–ZrO2, TiO2, and SiC), were tested in a crossflow microfiltration system using oil/water emulsions. The emulsions were stabilized by anionic and cationic surfactants. The fouling caused by filtration is discussed in terms if membrane and emulsion properties. Pore size and surface charge were the two most important prominent fouling factors during the oil/water emulsion filtrations. For membranes with small pores, serious fouling was observed, irrespective of the type of surfactant; however, these membranes exhibited excellent oil rejection. The fouling was caused by the accumulation of oil droplets on the membrane surface, which subsequently led to the formation of a cake layer and/or a continuous oil layer. The effect of surface charge became significant regarding membranes of larger pore sizes, especially when membrane pore sizes were comparable to that of the droplet sizes. When the membrane and oil droplets had the same charge, electrostatic repulsion occurred, preventing the penetration of oil droplets into the pores. Although some of the small oil droplets could enter the pores, they would be trapped at the narrowing and/or flexing inside the pores because droplet deformation was inhibited by the electrostatic repulsion. Therefore, fouling occurred on the membrane surface and inside. As a result, a severe decline in water permeation was observed, together with a moderate oil rejection. By contrast, when the membrane and oil droplets were oppositely charged, oil droplets were deformed and entered the pores, resulting in permeation through the membrane. Therefore, water permeation was high, but oil rejection was sacrificed. These results indicate that both pore size and surface charge of membranes should be optimized to achieve better filtration performance.

An 85-year-old cachectic man was found unconscious in his home. He had no specific medical history. On arrival, he was in a deep coma and hypothermic state. He had a soft mass the size of his fist in the right lower abdomen without redness or heat. Truncal computed tomography revealed subcutaneous fluid collection with gas formation. A test puncture for right lower abdominal subcutaneous fluid collection revealed pus, so an open incision was performed, with the administration of broad-spectrum antibiotics. Unfortunately, the patient died of sepsis-induced multiple organ failure. The results of abscess culture later revealed Proteus mirabilis, Escherichia coli, and Prevotella melaninogenica. This is the first report of a cold abscess induced by mixed bacteria.

Bis(triethoxysilyl)propane (BTESP) is a bridged-type organoalkoxysilane with a Si-C3H6-Si bond. It was utilized for membrane fabrication via a sol-gel method to achieve high permselectivity for large molecules. Membrane fabrication parameters such as the acid molar ratio (AR) in the sol and calcination temperature were evaluated for their effect on the network pore size and on gas permeation properties, as evaluated by the molecular size dependence (0.26–0.55 nm) and temperature dependence (50–200 °C) of gas permeance. BTESP membranes with different ARs (10−1, 100, and 10) showed H2/N2 and H2/CF4 selectivities of 20–30 and 640–32,000, respectively. As AR was increased, each gas permeance also increased, but H2 selectivity that corresponds to network pore size was decreased. FT-IR analysis indicated that the density of the Si-OH groups (Si-OH/Si-O-Si) of unfired gels was decreased with a higher AR, so that condensation of the Si-OH groups during the calcination process formed a dense network structure in the case of BTESP membranes with a low AR (10−1). Calcination temperature also affected the network structure of BTESP membranes. BTESP membranes calcined at different temperatures (350, 450, and 600 °C) showed H2/N2 and H2/CF4 selectivities of 10–30 and 410–32,000, respectively. A BTESP membrane calcined at high temperature (600 °C) showed loose networks since the linking units derived from BTESP were decomposed at temperatures above 500 °C, which resulted in the formation of methyl groups. In conclusion, the AR in a sol is suitable for tuning small pore sizes, while calcination temperature as a membrane fabrication parameter offers the advantage of controllability for loose network structures.

Membrane-based separation techniques are responsible for great advances in the separation of propylene/propane mixtures. In this study, bis(triethoxysilyl)acetylene (BTESA) was selected as the precursor in the fabrication of organosilica membranes for use in propylene/propane separation. We proposed an effective strategy to finely engineer the pore subnano-environment of BTESA membranes for highly selective propylene/propane separation via controlling the calcination temperatures. Measurement of the surface energy, the 29Si-NMR spectra, and the gas sorption isotherms clearly indicated that low-temperature calcined BTESA materials with a greater number of silanol groups showed an enhanced affinity to propylene molecules. BTESA membranes calcined at 150 °C featured a promisingly high C3H6/C3H8 selectivity of 52 and a C3H6 permeance of 1.7 ✕ 10−8 mol m−2 s−1 Pa−1 at 50 °C. These values were approximate to those reported for ZIF-8 membranes and higher than the standards for commercialization. The high level of C3H6/C3H8 separation performance was believed to be accounted by the synergetic effects of both controlled pore size and enhanced affinity to propylene molecules. Moreover, compared with traditional organosilica membranes that were calcined at ~350 °C, low-temperature calcination (150 °C) for BTESA membranes efficiently reduced the energy consumption and fabrication cost.

We developed a procedure that saves significant amounts of energy during the separation of organic liquids via organic solvent reverse osmosis (OSRO). The proof-of-concept was confirmed using theoretical calculation to demonstrate energy-consumption at less than 1/100th and 1/10th that of conventional distillation and pervaporation (PV), respectively. Bis(triethoxysilyl)acetylene (BTESA)-derived organosilica membranes consisting of a SiO2–ZrO2 intermediate layer and an α-Al2O3 support were evaluated by challenging a series of azeotropic mixtures of methanol/toluene, methanol/methyl acetate, methanol/dimethyl carbonate (DMC), and methanol/methyl tert-butyl ether (MTBE). BTESA membranes showed excellent size- and/or shape-sieving properties and remarkable levels of organic-tolerance with an ultrahigh methanol flux that outperforms state-of-the-art polymeric membranes. In particular, the robust ceramic support and rigid organosilica networks endowed the resultant membranes with the ability to withstand transmembrane pressures as high as 18 MPa.

The separation of azeotropic mixtures such as methyl acetate and methanol via a membrane is an interesting and challenging issue, since the membrane must be able to withstand these harsh solvents and provide good flux and selectivity. SiC-based membranes have attracted a great deal of interest due to their high mechanical strength, structural stability, and corrosion resistance at elevated temperatures. Herein, we describe the first use of polytitanocarbosilane (TiPCS), which is known as a precursor of continuous Si–Ti–C–O fibers (Tyranno), in the preparation of Ti-incorporated SiC-based membranes for the pervaporation (PV) removal of water or methanol, and describe the evaluation of hydrothermal stability. For this study, the physical and chemical properties of TiPCS-derived materials during pyrolysis were characterized via TG-MS, ATR-FTIR, XPS, XRD, and N2 adsorption-desorption isotherms. The pore characteristics and surface areas of TiPCS-derived ceramic powders revealed that the titanium components in TiPCS inhibit and/or reduce the densification of the network structures at elevated temperatures. The network structure of TiPCS-derived, SiC-based membranes showed trends similar to those of TiPCS-derived ceramic powders. The membrane prepared at 750 °C featured reproducibility and attractive selectivities for the PV removal of water or methanol from liquid mixtures.

The aim of this work was to study the fouling and cleaning behavior of bis(triethoxysilyl)ethane (BTESE)-derived organosilica membranes, which is a new class of RO membranes that feature chlorine tolerance and thermal stability. The foulants used in this study included bovine serum albumin (BSA) and sodium alginate (SA), which are typical examples of effluent organic matter (EOM). Sodium dodecyl sulfate (SDS) and dodecyltrimethyl ammonium bromide (DTAB) surfactants served as typical industrial waste. With the EOM foulants, BSA fouling occurred at a pH that approximated its iso-electric point (IEP), and the fouling became more severe with the addition of electrolytes into the SA solution. In both cases, however, the fouled BTESE membrane was recovered with the use of deionized water (DIW). The fouling was more pronounced in the presence of DTAB by comparison with SDS surfactants. Surprisingly, in all tests, within 30 min and without the need of chemical agents, the integrity of the fouled BTESE membranes was recovered by applying water at a temperature of at least 80 °C.

Ceramic microfiltration membranes with superior chemical and mechanical stability for sustainable operation under harsh conditions have demonstrated great potential for industrial wastewater treatment. In this study, low-cost ceramic microsheet membranes with a thickness of sub-0.5 mm that possess superhydrophilic and underwater superoleophobic properties were fabricated from an Al2O3-rich Al2O3/polysulfone composite slurry via a phase inversion/sintering strategy. The cross-sectional morphologies of these phase inversion-induced composite films appear as ceramic green bodies that can be precisely controlled by tuning the operation parameters during the classic phase-inversion process of a polymer, which allows the morphology to withstand a subsequent high-temperature (1250 °C) sintering process. The thinner nature ( 99% and a much higher emulsion permeability of ~3,000 L/(m2 h bar), which is 2 orders of magnitude higher than most commercially available microfiltration membranes that are capable of similar levels of separation performance. This process resulted in a favorable membrane that combines robustness under complex chemical environments with low cost for both materials and processing approaches, which should facilitate its practical application in the industrial treatment of oily wastewater.

Context: Few reports have investigated the time course of fibrinogen (or fibrin) degradation product (FDP) levels for trauma patients in the subacute phase. Aims: This study aimed to investigate the time course of the FDP levels among patients with moderate and severe trauma in the subacute phase. Settings and Design: A retrospective medical chart review in a single hospital. Subjects and Methods: From September 2017 to March 2018, a medical chart review was retrospectively performed for all patients with trauma who were admitted to our department, and these patients were included as participants in the present study. We collected the data on each patient's sex, age, presence of head injury, mechanism of injury, Glasgow Coma Scale on arrival, systolic blood pressure, heart rate, type of injury (blunt versus penetrating), injury severity score, complication of infection, surgical procedure, duration of admission, survival rate, and FDP level from the 1st to 7th hospital day. The average level of FDP on each hospital day was compared with that on the previous day. Statistical Analysis Used: The statistical analyses were performed using a paired Student's t-test. P < 0.05 was considered to indicate a statistically significant difference. Results: From the 1st to 4th hospital day, the average level of FDP significantly diminished day by day. However, from the 5th hospital day, the average level significantly increased. This trend persisted even after excluding the complications of infection and surgical procedures performed between the 2nd and 7th hospital day. Conclusions: Among trauma patients, the average level of FDP significantly diminished day by day from the admission to the 4th hospital day; however, from the 5th hospital day, the average level significantly increased. Further studies are needed to determine the time course of FDP or D-dimer levels in the long term and when FDP levels return to normal limits.

This article focuses on control of film thickness and roughness to improve the ultraviolet (UV)-protective performance of TiO

Networking is an indispensable tool for disaster situations. Since it is predictable that there are no professional technicians around the place where the faults occur, a solution of collaborative problem solving between humans and agents makes the non-professionals to improve that situation. In this paper, to address the errors of the network under the disaster situation, we propose a multi-modal interaction mechanism for temporally organized groups of humans and agents who accidentally present at a short distance. A prototypical system including the proposed mechanism and the network management support agents shows that the flexible collaboration realizes the useful restoration.

Introduction In 2011, our hospital on the Izu peninsula began to hold meetings to discuss how to manage patients with decompression illness (DCI) to establish a cooperative medical system. We retrospectively investigated the influence of these meetings and the changes subsequently effected. Methods A medical chart review was retrospectively performed to investigate all cases between January 2005 and December 2017 in which the transport of patients with DCI via a physician-staffed helicopter emergency medical service (HEMS) was attempted. The patients were divided into 2 groups: the preprogram group and the postprogram group. Results There were 63 patients in the preprogram group and 65 in the postprogram group. There were no cases in which a patient's symptoms deteriorated during transportation by the HEMS. The frequency of dispatch to the scene for direct evacuation in the postprogram group (86%) was greater than that in the preprogram group (74%), but the difference was not statistically significant (P=0.09). In the postprogram group, the duration of activities at the scene or the first aid hospital was significantly shorter in comparison to the preprogram group (P=0.01). Conclusions This retrospective study revealed simultaneity between the introduction of the yearly meetings and a reduced duration of the HEMS staff's activity at either the scene or the first aid hospital.

A physician-staffed helicopter emergency medical service called a doctor helicopter (DH) in Eastern Shizuoka was equipped with a smartphone video transmission system in April 2018. We herein report on the introduction of this system for the verification of transfusion in the DH. A 51-year-old man visited a local hospital after cutting his left neck himself. He was diagnosed with jugular vein injury and underwent compressive hemostasis. As he entered profound hemorrhagic shock, he underwent tracheal intubation, massive fluid resuscitation, and administration of 3 vasopressor agents to maintain circulation. The Eastern Shizuoka DH was requested to transport this patient. After making contact with the patient, the staff of the DH started prehospital transfusion. Because this was the first case of transfusion in a prehospital setting for our hospital, we held a meeting in which we used a smartphone video transmission system to verify the condition surrounding the transfusion in the DH. By reviewing the video record, we confirmed that the transfusion was performed safely and correctly in the prehospital setting. This smartphone video transmission system was useful for verifying the activity of the staff in the DH.

We retrospectively investigated the risk factors for the occurrence of traumatic vacuum phenomenon (TVP) after chest compression for patients with cardiopulmonary arrest (CPA) using computed tomography (CT). A medical chart review was performed for all patients with out-of-hospital endogenous CPA. The subjects were divided into two groups: TVP + group and the TVP – group. 110 patients were enrolled as subjects. TVP was observed in 33. The rates of witness collapse and rib fracture were significantly higher in the TVP + group than in the TVP – group. The duration from the commencement of CPR by emergency medical technicians to the CT examination in the TVP + group was significantly longer than in the TVP – group. Accordingly, among patients with out-of-hospital CPA, witness collapse, rib fracture and a longer duration from the commencement of cardiopulmonary resuscitation (CPR) by EMTs to the CT examination were risk factors for TVP.

Various types of amine-functionalized silica/organosilica membranes have been developed due to their potentially superior CO2 separation performance. This article reviews the progress made in this field and special attention is paid to elucidating the role of amine type in CO2 separation performance within amine-functionalized silica/organosilica membranes. This review includes a systematic comparison of various organosilica membranes with either unhindered or sterically hindered amines developed in our previous studies. Herein, we thoroughly discuss the structural characterizations and CO2 adsorption/desorption properties of amine-functionalized xerogel powders and CO2 transport/separation performance across the relevant membranes. Future directions for the design and development of high-performance CO2 separation membranes are suggested, and particular attention is paid to the future of activation energies for gas permeation.

Ceramic membranes were newly developed with hydrophobic intermediate layers to achieve high gas permeance in the presence of water vapor. Me-SiO 2 sols, which were prepared by co-precursors of tetraethoxysilane (TEOS) and methyltrimethoxysilane (MTMS) were coated as intermediate layers. Two types of organosilica sols prepared with bis(triethoxysilyl)ethane (BTESE) and bis(triethoxysilyl)octane (BTESO) were used for the top layers. By characterization of nanopermporometry using hexane and water as condensable vapors, Me-SiO 2 layers showed pore diameter of approximately 1.5 nm and exhibited hydrophobic properties and that SiO 2 –ZrO 2 layers were hydrophilic. BTESE- and BTESO-derived sols were coated on hydrophobic Me-SiO 2 layers, referred to as BTESE/Me-SiO 2 and BTESO/Me-SiO 2 , and on hydrophilic SiO 2 –ZrO 2 layers, which are referred to as BTESE/SiO 2 –ZrO 2 and BTESO/SiO 2 –ZrO 2 . Gas permeation was examined for four types of membranes under a dry and a wet atmosphere. Under dry conditions, BTESO/Me-SiO 2 showed a gas permeation trend that was similar to that of BTESO/SiO 2 –ZrO 2 . The selectivity of H 2 /SF 6 for BTESE/Me–SiO 2 (334) was much lower than that of BTESE/SiO 2 -ZrO 2 (>20,000) due to the inhomogeneous coatings of BTESE on the Me-SiO 2 layers. Under humidified conditions, BTESE/Me–SiO 2 and BTESO/Me-SiO 2 with hydrophobic intermediate layers, exhibited less of a decrease in CO 2 permeance compared with either BTESE/SiO 2 -ZrO 2 or BTESO/SiO 2 –ZrO 2 , both of which had hydrophilic intermediate layers. The water vapor resulted in a negligible effect on gas permeance for totally hydrophobic BTESO/Me-SiO 2 , while a little larger decrease was observed for hydrophilic top layers of BTESE/Me–SiO 2 , showing that membranes with hydrophobic surface chemistry can effectively resist water vapor condensation or adsorption during gas permeation.

Organosilica membranes were fabricated under controlled sol-preparation conditions such as the ratio of triethoxysilane (TRIES) and vinyltrimethoxysilane (VTMS) and the hydrosilylation temperature. The single-gas permeation properties and hydrothermal stability of organosilica membranes were evaluated to clarify the relationship between hydrothermal stability and organosilica structure. Pt-catalyzed and thermally cured hydrosilylation was applied to evaluate the effect that hydrosilylation temperature exerts on the properties of membranes. Organosilica membranes (Pt-catalyzed hydrosilylation at 40 °C) showed H 2 permeance of approximately 10 −6 mol m −2 s −1 Pa −1 with H 2 selectivity (H 2 /CH 4 :15, H 2 /CF 4 :950) at 500 °C, and were stable under an oxidative atmosphere at 500 °C. The organosilica network size derived by thermal curing at 500 °C was smaller than that by Pt-catalyzed hydrosilylation, even though the units (Si–C–C–Si, Si–O–Si) were the same. Hydrosilylation reactivity derived by thermal curing (500 °C, N 2 ) strongly depended on the TRIES/VTMS (= H / V ) ratio in the SQ sol, and an H / V ratio of 1.25 showed a higher level of hydrosilylation reactivity. Its hydrothermal stability was better than that of amorphous silica membranes, due to the incorporation of Si–(CH 2 ) 2 –Si units in the networks via hydrosilylation, based on the decreased ratio of He and H 2 permeance, the He/H 2 permeance ratio, and the activation energy before/after steam treatment.

A novel layered-hybrid membrane consisting of a thin and defect-free organosilica separation layer deposited onto a flexible polymeric nanofiltration membrane was successfully developed via a simple sol–gel, spin-coating, low-temperature, heat-treatment process. This marked the first application of this type of a layered-hybrid membrane to the reverse osmosis (RO) desalination of a 2000 ppm NaCl solution. The optimal heat-treatment temperature for the membrane preparation was also investigated. These layered-hybrid membranes displayed good stability and reproducibility in the RO process, and showed a stable and high degree of water permeability (approximately 1.2×10 −12 m 3 m −2 s −1 Pa −1 ) with salt rejection that was competitive (96%) with conventional processing. Moreover, this layered-hybrid membrane also showed good hydrothermal stability at operating temperatures ranging from 25 to 60 °C and stable RO performance during a continuous RO desalination process that lasted for more than 160 h.

A pore network of bis(triethoxysilyl)ethane (BTESE) organosilica membranes was controlled by adjusting the molar ratios of BTESE/H2O/acid=1/x/0.2 (x=3 and 240). The mechanisms for solute transport in the BTESE RO membrane were investigated using three different aqueous solutions of sodium chloride (NaCl), ethanol (EtOH) and isopropanol (IPA). The pressure and temperature were varied from 0.4 to 1 MPa and from 25 to 80 °C, respectively. Water flux and rejection increased for both alcohols and electrolyte with an increase in the applied pressure. It was noteworthy that the rejection of alcohols decreased with an increase in the RO operating temperature, while the electrolyte rejection remained almost constant. The BTESE membranes exhibited high thermal robustness under the long-term testing conditions, delivering salt rejections >98% until the end of the testing period (50 h). The BTESE membranes could also be regenerated after use in the gas and RO experiments, thus demonstrating robust properties.

Organosilica membranes for gas separation were prepared by plasma-enhanced chemical vapor deposition (PECVD) using three different types of silicon precursors: hexamethyldisiloxane (HMDSO), trimethylmethoxysilane (TMMOS), and methyltrimethoxysilane (MTMOS). Based on gas permeation measurement, the MTMOS-derived membrane showed the highest He/N2 selectivity, followed by the TMMOS-derived and HMDSO-derived membranes. FT-IR characterization indicated that the HMDSO-derived membrane had the highest content of methyl group and the lowest Si O Si, while the methyl group content for the MTMOS-derived membrane was the lowest and Si O Si was the highest. These results suggest that the pore size of organosilica membranes could be tuned by changing the chemical structure of the silicon precursor. The MTMOS-derived membrane was further heat-treated to determine the effect of thermal annealing on gas-permeation properties. The gas permeances were drastically improved by the thermal annealing. After heat-treatment at 500 °C, the membrane showed a high H2 permeance of 6.5×10−7 mol/(m2 s Pa) with a H2/SF6 selectivity of 410 at 200 °C, and 5.6×10−7 mol/(m2 s Pa) with a H2/SF6 selectivity of 360 at 50 °C.

Uniform and defect-free silica films were prepared by spin-coating silica sols on plasma-treated hydrophobic sub-layers. Three kinds of silica films were prepared using tetraethoxysilane (TEOS), bis(triethoxysilyl)ethane (BTESE) and bis(triethoxysily)octane (BTESO) via sol–gel method. First, hydrophobic sub-layers were pre-coated on silicon wafers with Me-SiO 2 sols prepared from mixtures of methyltrimethoxysilane (MTMS) and TEOS. After firing at 400 °C, the films showed water contact angles of 120°. Then TEOS- and BTESE-derived sols were directly spin-coated on the Me-SiO 2 films, resulting in separated and scattered coatings. A H 2 O/N 2 plasma modification method was used to change the properties of the Me-SiO 2 films from hydrophobicity to hydrophilicity without damaging either the surface morphology or the bulk chemistry. After the treatment, the TEOS- and BTESE-derived sols formed homogenous films. On the other hand, the Me-SiO 2 films were fully coated with BTESO either with or without plasma treatment. This was probably due to both the polar (–OH) and non-polar (long –CH 2 ) portions of the BTESO-derived sols. For gas separation applications, the corresponding BTESE membranes showed great improvement in gas selectivity after the plasma treatment of hydrophobic Me-SiO 2 layers.

The effect of the operation conditions on the recovery of acid–alkali pairs by electrodialysis was studied to improve the efficiency of the newly developed mineral carbonation process for carbon dioxide fixation. Sodium nitrate (NaOH + HNO3), sodium chloride (NaOH + HCl), and potassium chloride (KOH + HCl) showed almost equal performance in the recovery process for the two fixed membrane configurations. For the same salt, the configuration of anion-exchange membrane bipolar membrane (AEM–BPM) showed higher recovery rate and lower power consumption than the cation-exchange membrane bipolar membrane (CEM–BPM) configuration. Significantly higher recovery rates were observed when potassium acetate was used for the CEM–BPM configuration. A higher recovery rate was observed for a lower initial concentration, but the power consumption was lower for higher initial concentrations. Calcium in waste cement powder can be rapidly leached with acetic acid. The results showed that the process performance would be signif...

A modified gas-translation (GT) model based on a GT mechanism was successfully applied to the pore-size evaluation and gas transport behavior analysis of microporous membranes with different pore-size distributions. Based on the gas permeation results of three microporous membranes derived from different alkoxides, the effects of activation energy and the selection of a standard gas on the pore-size evaluation were discussed in a comparative study. The presence of nano-sized defects had an important influence on the gas permeation performance of microporous membranes, depending largely on the original pore size of the membrane in question. Moreover, the gas-separation effect of the pore-size distribution in a silica membrane was theoretically studied and revealed a significant increase in gas permeance for relatively large gas species but not for small ones. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2268–2279, 2015

The dehydrogenation of methylcyclohexane (MCH) to toluene (TOL) for hydrogen production was theoretically and experimentally investigated in a bimodal catalytic membrane reactor (CMR), that combined Pt/Al2O3 catalysts with a hydrogen-selective organosilica membrane prepared via sol-gel processing using bis(triethoxysilyl) ethane (BTESE). Effects of operating conditions on the membrane reactor performance were systematically investigated, and the experimental results were in good agreement with those calculated by a simulation model with a fitted catalyst loading. With H2 extraction from the reaction stream to the permeate stream, MCH conversion at 250°C was significantly increased beyond the equilibrium conversion of 0.44–0.86. Because of the high H2 selectivity and permeance of BTESE-derived membranes, a H2 flow with purity higher than 99.8% was obtained in the permeate stream, and the H2 recovery ratio reached 0.99 in a pressurized reactor. A system that combined the CMR with a fixed-bed prereactor was proposed for MCH dehydrogenation. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1628–1638, 2015

Silsesquioxane (SQ) membranes derived from 3-methacryloxypropyltrimethoxysilane and bis(trimethoxysilyl)ethane were successfully fabricated at low temperature via photo-induced sol-gel processing. Radical and cationic polymerization of SQ membranes showed high degrees of separation factor and permeance for water/isopropanol separation in pervaporation.

Objective The aim of this study was to identify the prognostic factors of cardiopulmonary arrest (CPA) patients transported by a physician-staffed helicopter who received cardiopulmonary resuscitation (CPR) using AutoPulse (ZOLL Circulation, Sunnyvale, CA). Methods A total of 110 CPA patients who had CPR performed on them in the helicopter using AutoPulse were enrolled in this retrospective study. We used logistic regression analysis to examine the prognostic factors of CPA patients who were transported by a physician-staffed helicopter. Results Of these patients, return of spontaneous circulation (ROSC) during transportation was observed in 19 (17.29%); 1 (.9%) survived through hospital discharge without neurologic disability. In multivariate analyses, bystander CPR (P = .023) and the time from the first call to the arrival of a helicopter medical crew (P = .041) were selected as independent factors associated with ROSC. Conclusion In our study, factors such as early contact from the first call to the arrival of a helicopter medical crew and the presence of bystander CPR appeared to play an important role in attaining ROSC of CPA patients who were transported by a physician-staffed helicopter using AutoPulse.

Real spinal cord injury without radiologic abnormality (SCIWORA) is a rare clinical entity. The patient was a 13-year-old girl whose body was overturned anteriorly after crashing her bicycle into a curb. Following the accident, in which her neck and upper back hit the ground, she could not move due to paralysis. On arrival, she had paresis of the bilateral upper extremities and experienced a painful sensation when her upper extremities were touched. Cervical roentgenography and whole-body computed tomography revealed no traumatic lesions in either the intracranium or the cervical bone. Urgent spinal magnetic resonance imaging (MRI) showed no significant spinal cord lesions or spinal canal stenosis. She was put on complete bed rest with a cervical collar. On the 2nd hospital day (24 h after the accident), her motor weakness had almost completely subsided, and she felt only mild dysesthesia in both forearms. Roentgenography revealed no instability. Her motor weakness completely recovered on the third day after accident and she was diagnosed with spinal cord concussion. The present case study, in which MRI was performed, showed that an immediate improvement was obtained in a patient who experienced real SCIWORA. The importance of not only spinal cord lesions, but also perispinal soft tissue injury on MRI has been emphasized for predicting patient outcomes. Accordingly, immediate MRI is essential for evaluating patients with signs and symptoms of spinal cord injury, even when plain neck roentgenography and cervical CT are negative.

The fire department in Atami received an emergency call at 6:17 am , with notification of 4 or 5 casualties because of a fire. Because there was only 1 ambulance (O) at the station, an additional ambulance (P) was also requested. Ambulance O transported 2 patients (A and B), and ambulance P transported 2 patients (C and D). These 4 patients were judged to have severe inhalation injuries at the scene and were transported to 2 local hospitals (X and Y). After patients C and D arrived at hospital Y, the medical staff decided to transfer them to the emergency medical service center. Patient C was transported by an emergency medical helicopter (doctor helicopter), and patient D was transported to our hospital by ambulance P. After tracheal intubation, both patients (C and D) required intensive care and mechanical ventilation. Patient A at hospital X was also intubated and transported to another hospital by the doctor helicopter. Fortunately, all patients survived. After a review among the parties involved in the incident, initiating an early request for additional human resources, vehicles, and medical support was recognized as contributing a key role in achieving a successful outcome.

Pervaporation is an important unit operation for the separation of liquid mixtures because of its advantages in the separation of, for example, azeotropes and close-boiling-point mixtures. Silica and silica-based membranes have micropores which can separate molecules based on their size differences, and are, therefore, promising candidates to be used in pervaporation. The development of silica and silica-based membranes for pervaporation is reviewed and their separation performances are presented.

In this study a new type of layered hybrid membrane was fabricated. This new membrane consisted of a thin organically bridged silica separation layer deposited onto the surface of a flexible polymeric membrane, NTR-7450 (Nitto Denko, Japan), and was comprised of a sulfonated polyethersulfone top layer and a porous polysulfone support. Using 1,2-bis(triethoxysilyl)ethane (BTESE) as a precursor, a continuous and defect-free BTESE separation layer was deposited onto the surface of a polymeric nanofiltration membrane via a facile, reproducible and scalable sol–gel spin-coating and low-temperature curing process. First, the optimal preparation conditions were established, which included the curing temperature and the spin-coating cycles. The membranes were then used for the vapor permeation dehydration of isopropanol-water solutions, and showed a stable water flux of 2.3 kg/(m2 h) and an improved separation factor of about 2500, which was an increase of approximately 5-fold compared with that of a polymeric nanofiltration membrane. In addition, single-gas permeance through this membrane was also discussed and a modest H2/N2 selectivity of 26 was obtained, which approximated the performance of ceramic-supported BTESE-derived silica membranes.

The sol–gel method was applied to the fabrication of Al-doped bis (triethoxysilyl) methane (BTESM)-derived membranes. The single-gas permeation properties for Al-doped BTESM-derived membranes were examined to evaluate the effect of aluminum concentration on amorphous silica network sizes. Each permeance was decreased with an increase in the Al concentration, and the H 2 /CH 4 and H 2 /C 3 H 8 permeance ratios increased with an increase in Al concentration. For example, an Al-doped BTESM (Si/Al=8/2) membrane fabricated at 200 °C showed a H 2 permeance of 4.4×10 −7 mol m −2 s −1 Pa −1 , which was approximately 1/10th that of a BTESM membrane fabricated at 200 °C. The H 2 /CH 4 and H 2 /C 3 H 8 permeance ratios were 60 and 2700 with Al doping, but 30 and 1000 without Al-doping, respectively. The activation energy of He, H 2 , N 2 , and CH 4 permeation was increased with an increase in the Al concentration, indicating that the pore size of BTESM-derived networks was decreased with an increase in Al concentration. The decrease in BTESM-derived network sizes that resulted from an increase in the Al concentration can be ascribed to the absolute amount of Al incorporated into BTESM-derived networks and/or coordinated with Si-OH groups, as suggested by 27 Al MAS NMR. High C 3 H 6 /C 3 H 8 permeance ratios of approximately 40 for Al-doped BTESM (Si/Al=9/1) membranes fabricated at 200 °C were achieved through the precise control of the silica network size via a spacer method using Si–C–Si units as well as the incorporation of Al in BTESM-derived networks.