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Zeolite Beta has been widely utilized on large molecular systems because of its three dimensional large micropores, 12-membered ring. Controlling amount of acid and its strength of zeolites depending on the composition is very crucial to improve their catalytic performance. Incorporation of heteroatoms into the framework of zeolites is one of the effective ways to control catalytic activities. However, it is difficult to synthesize high-silica zeolite Beta with heteroatoms, which has been limiting the functions of zeolite Beta. To overcome the problem, we developed a dry gel conversion method using dealuminated zeolites; we can synthesize *BEA type ferrisilicate (Fe-Beta). In this method, it is necessary to use two silica sources; dealminated Beta and colloidal silica. The dissolving process of these silica sources by NaOH plays a significant role in the crystallization to Fe-Beta. The Fe-Beta shows higher selectivity to isobutene on acetone-to-olefins (ATO) reaction compared to Al-Beta and Fe-MFI. This is due to the acid strength weakened by substituting Al by Fe and the large diffusivity of isobutene in the large micropores of *BEA structure.

Propane dehydrogenation (PDH) is one of the most promising candidates for the propylene production process to meet the growing demand of propylene for the future. There is an urgent need to develop catalysts for PDH. In this work, we have synthesized high silica Ga-Beta as a new candidate for a catalyst from dealuminated zeolite using the dry gel conversion method. A high silica Ga-Beta catalyst with a Si/Ga ratio of up to 177 can be synthesized. In the PDH reaction, the synthesized Ga-Beta showed the highest propane conversion and the highest propylene yield amongst the Ga-based zeolites. The combination of the Ga species being incorporated into zeolite frameworks, its large microporosity and Bronsted acidity is likely to lead to the excellent catalytic performance of Ga-Beta. Moreover, Ga-Beta with a higher Si/Ga ratio shows a longer catalyst lifetime for the PDH reaction, since the coke deposition rate decreased with the decrease in the amount of acid. This work provides new insights for the PDH reaction over Ga-based zeolite catalysts, and contributes to the progress in the activation and transformation of light alkenes to value-added chemicals.

Background: Breath sound parameters have been suggested as biomarkers of the airway narrowing in children. Using a commercially available breath sound analyzer, the characteristics of the airway condition were investigated in infants with the risk factors for asthma development. Methods: A total of 443 infants (mean age, 9.9 months; range, 3–24 months) were included in the present study. The breath sound parameters of the frequency limiting 99% of the power spectrum (F99), the roll-off from 600 to 1200 Hz (Slope) and spectrum curve indices, the total area under the curve of the dBm data (A3/AT) and the ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF75 and RPF50), were evaluated. Using an ATS-DLD based original Japanese questionnaire, we examined the characteristics of airway condition of infants. Results: Finally, 283 infants in good health were included in the present study. The RPF75, RPF50, Slope and F99 in infants with positive results of allergy and atopic dermatitis were significantly increased more than those in the infants with negative result. Conclusions: Our data highlight the characteristics of breath sounds in infants with risk factors for asthma. The breath sound analysis may be useful for assessing the airways of infants for asthma development. Keywords: Asthma, Breath sound analysis, Infant, Risk factors, Sound spectrum

In this work, a dual-functional catalyst with (1) catalytic activity of metal catalysts and (2) shape-selectivity of zeolites has been developed. We have fabricated Pt nanoparticles encapsulated in core-shell single crystal like silicalite-1 zeolite (CS-Pt/s-1) by a crystalline overgrowth method. The CS-Pt/s-1 catalyst showed much higher catalytic hydrogenation activity of n-hexene compared to cyclohexene.

Silicalite-1 zeolite membranes were prepared on porous tubular α-Al2O3 supports by a secondary growth method. The influences of the Si/Al ratio and the amount of deposited MFI (silicalite-1 and ZSM-5) seed crystals on membrane pervaporation (PV) performance for the separation of ethanol/water (binary) and ethanol/water/succinic acid (ternary) mixtures were investigated. The prepared membranes were characterized by X-ray diffraction and scanning electron microscopy, and the Si and Al distributions in the membrane layers were determined by energy-dispersive X-ray line scanning. Each silicalite-1 membrane was composed of two layers: an MFI-seed-crystal layer that grew on the support surface, and another gel-derived silicalite-1 top layer that formed on the seed crystal layer. The texture of the MFI seed layer (i.e., the deposited amount and the Si/Al ratio) was found to play an important role in the separation process. When silicalite-1 seed crystals were used, the ethanol separation factor was high in the binary ethanol/water system, but lower in the presence of succinic acid. However, when ZSM-5 seeds were used, the ethanol separation factor in the ternary system improved. These results suggest that silicalite-1 membranes prepared using ZSM-5 seed crystals are effective for the recovery of ethanol in the presence of organic acids.

A highly reproducible silicalite-1 membrane with high pervaporation performance was successfully prepared on a tubular silica support by a novel seeding method using a zeolite-dispersed polymer film. The proposed seeding method (film seeding) allowed for the formation of a uniform and continuous zeolite seed layer with high reproducibility on the support surface in a single seeding step, resulting in a membrane with high separation performance. The synthesized membrane had a continuous and dense zeolite layer with a thickness of approximately 12 μm and exhibited an ethanol/water separation factor of 120 and flux of 3.16 kg m−2 h−1 for 10 wt% ethanol/water mixtures at 323 K by pervaporation. This novel seeding method should lead to the development of new processes for synthesizing zeolite membranes that show both high performance and reproducibility. Moreover, given the simplicity and effectiveness of the method, it has immense potential for use in the commercial production of various types of zeolite membranes.

Ethane dehydroaromatization (EDA) reaction is one of the promising processes to meet the growing demand of aromatics in the future. Zn ion exchanged MFI type aluminosilicate zeolite (Zn/[Al]-MFI) shows high activity on EDA reaction. Zn ion and Bronsted acid derived from Al sites contribute to the high activity on EDA reaction, but excess strong acid sites promote coke formation, leading to rapid deactivation. Herein, we have developed a new synthesis method for Zn ion exchanged MFI type galloaluminosilicate zeolite (Zn/[Ga,Al]-MFI). The coke formation was suppressed by partially substituting Al with Ga since acidity derived from Ga sites are weaker than that derived from Al sites. Zn/[Ga,Al]-MFI was the ideal catalyst to achieve both high catalytic activity and stability on EDA reaction. Our work provides a new design direction of zeolite catalysts on EDA reaction, which can contribute to the progress on the transformation of light alkanes to value-added chemicals.

The basicity of ZrO2 support was successfully controlled by doping La and alkaline earth metals. La doping significantly increased weak basic sites, and medium and strong basic sites appeared by the further increase of La doping. Mg and Ca doping on La doped ZrO2 increased weak and medium basic sites, respectively. Significant increase of total number of basic sites including strong basic sites was observed by Sr doping. In ammonia decomposition, turn over frequency (TOF) of ammonia over Ru supported ZrO2 and metal doped ZrO2 exhibited a good relation to the number of medium and strong basic sites. From TOF with different reaction temperature, it was supposed that the higher basicity is effective to recombinative desorption of nitrogen at lower reaction temperatures, whereas the number of medium basic sites would be effective at a high reaction temperature. Catalytic activity in dry reforming of methane was evaluated over Ru supported ZrO2 and metal doped ZrO2 as well. The catalytic activity was improved by metal doping to the supports. Both TOF of CO2 and methane showed a good relation to the total number of basic sites as well as the number of medium and strong basic sites. It was interestingly found that H2/CO was increased with an increase in the total number of basic sites. This implies the weak basic sites would have a positive impact on H2/CO.

Silicalite-1 membranes with high pervaporation (PV) performance were prepared on a seeded tubular silica support using modified steam-assisted conversion (SAC) under gel-free conditions, called the gel-free SAC method, for the first time. The seeded support was first dipped in a TPAOH aqueous solution and dried. Subsequently, the TPAOH-coated silicalite-1 seed layer was converted into a silicalite-1 membrane layer, followed by heating in an autoclave with a small amount of water at the bottom of the autoclave. In this method, silica support was not only used as the support but also as the silica source to grow the zeolite seed layer into a continuous and dense zeolite membrane layer. In other words, no additional supply of silica source such as synthesis gel to grow the seed layer was required. The silicalite-1 membrane prepared in this study had a separation layer with a thickness of approximately 7 µm and exhibited high PV performance with a separation factor of 66 and high flux of 4.47 kg m −2 h −1 for 10 wt% ethanol/water mixtures at 323 K. This membrane preparation method is quite simple and uses minimum necessary reagents. Therefore, it is economical and suitable for the preparation of membranes on an industrial scale.

Production of bioethanol, a renewable energy source, is limited by the costly, energy-consuming concentration processes involved. Membrane separation techniques have emerged as promising alternatives to overcome these limitations. In this study, silicalite-1 zeolite membranes with high pervaporation (PV) performance were prepared on porous tubular silica supports by a secondary growth method. The effects of the deposited seed amount on the support and synthesis parameters, namely, the tetra- n -propylammonium concentration (TPA + /Si), alkalinity (OH − /Si), and crystallization time, were investigated. A dense zeolite layer was formed between the typical columnar crystal layer of silicalite-1 membranes and the silica support. The PV performance was mainly dependent on the thickness of the dense layer: as the thickness increased, the separation factor increased. The silicalite-1 membrane prepared using a synthesis solution with a molar composition of 1SiO 2 :0.05TPABr:0.08NaOH:75H 2 O at 433 K for 8 h exhibited the highest separation performance with a separation factor of 92 and a flux of 3.00 kg m −2 h −1 for 10 wt% ethanol/water mixtures at 323 K, which is the best result reported to date for tubular supports. Thus, silica supports proved to be suitable for the preparation of high-performance silicalite-1 membranes for ethanol/water mixture separation.

Mesoporous silicas with different pore size were modified by aminosilanes with different molecular length. CO2 adsorption capacity was improved by all aminosilane modification, and the CO2 adsorption capacity was further improved with increasing the aminosilane density. However, CO2 adsorption capacity and the amine efficiency of (3-trimethoxysilylpropyl)diethylentriamine (TA) modified mesoporous silicas with small pores such as MCM-41(2.9 or 3.1 nm) and SBA-15(6.2 or 7.1 nm) were significantly decreased at high aminosilane density. In contrast, TA modified SBA-15 with a large pore (10.6 nm) exhibited further improvement of CO2 adsorption capacity and amine efficiency. N2 adsorption desorption measurements suggested that the pore plugging occurred at high aminosilane density in TA modified mesoporous silicas with small pores. In situ FT-IR spectra and the half-value period of CO2 equilibrium adsorption capacity clearly shows the CO2 adsorption kinetics in these adsorbents with small pores were significantly lower than that in the adsorbent with large pores. To develop the CO2 adsorbents with high adsorption performance, the correlation between aminosilane molecular length, pore size of mesoporous silica and aminosilane density should be considered.

A UiO-66 membrane was synthesized on an Al2O3 support using an in-situ solvothermal method with a coordination modulation technique. We first confirmed the organic selectivity of the UiO-66 membrane from organic/water mixtures such as methanol, ethanol and acetone. The membrane displayed highly stable pervaporation performance during the test and exhibited a separation factor of approximately 4.3 and flux of 1.28 kg m-2 h-1 in ethanol/water. From the water and ethanol vapor adsorption measurement, the water uptake was lower in a binary system than that in a single system, although the ethanol uptake was similar between binary and single systems. Therefore, the ethanol selectivity of UiO-66 membrane would be owing to preferential adsorption of organic compound rather than water confirmed by a binary vapor adsorption measurement.

Silicalite-1 membranes supported on porous α-Al 2 O 3 supports were developed and used for pervaporation separation of acetic acid/water mixtures. The effects of the amount of deposited seed crystals on the α-Al 2 O 3 support and the H 2 O/SiO 2 ratio in the synthesis solution on the pervaporation separation performance of the membranes were investigated. Seed layers on the α-Al 2 O 3 support suppressed Al atom leaching from the α-Al 2 O 3 support during the hydrothermal treatment, resulting in improved membrane performance. The membrane prepared using a seed amount of ca. 5 g/m 2 and a H 2 O/SiO 2 ratio of 75, with the thickness of zeolite layer equal to ca. 9 μm, exhibited relatively high selectivities for ethanol/water and acetic acid/water mixtures. The total fluxes of the membrane were 0.47 and 0.04 kg/(m 2 h) toward 10 wt.% ethanol/water and 5 wt.% acetic acid/water mixtures, respectively and the corresponding separation factors were 88 and 33, respectively. For acetic acid/water mixtures, the silicalite-1 membranes prepared in this study exhibited a separation factor greater than those of any membranes previously reported, and a close correlation between the separation selectivity of ethanol for ethanol/water mixtures and that of acetic acid for acetic acid/water mixtures was revealed; i.e., the separation factor of acetic acid was equal to one-fourth of that of ethanol in organic/water mixtures of the same concentration.

Zeolites have been conventionally synthesized using organic structure directing agents (OSDA) in solvent. In this work, we synthesized various zeolites from unseeded aluminosilicate via mechanochemical and vapor treatments in the absence of OSDA and solvent. Various types of zeolites were successfully synthesized from starting materials with different Si/Al ratios. With an increase of Si/Al from 1 to 20, different phases appeared in the order of CAN, ANA, MOR, MFI and α-quartz. This work provides a new insight of zeolite synthesis.

Introduction: Component-resolved diagnostics is used to diagnose food allergies. However, few reports have evaluated the severity of peach fruit allergy using peach allergen components, including Pru p 7. Objective: This study aimed to predict peach fruit allergy severity based on the presence of specific IgE (sIgE) antibodies (Abs) to peach allergenic components. Methods: Twenty-seven patients with peach fruit allergy were enrolled and classified into two groups: the local reaction (LR) group, including 12 patients with only oral or throat mucosal symptoms, and the systemic reaction (SR) group, including 15 patients, 10 of whom experienced anaphylaxis. Serum sIgE Abs against crude peach extract – Pru p 1, 2, 3, 4, and 7 – and tree pollen were measured. Results: sIgE Ab titers of Pru p 1 and 4 and alder pollen in the LR group were significantly higher than those in the SR group. sIgE against Pru p 7 was significantly higher in the SR group than in the LR group. The frequencies of sIgE Abs against Pru p 1, 4, and 7 in the LR group were 91.7, 66.7, and 16.7%, respectively, while in the SR group these were 80, 20, and 60%. Sensitization to Pru p 2 and 3 was detected but limited in all patients. Conclusions: These findings suggest that sensitization to Pru p 1 and Pru p 4 is associated with local symptoms, and sensitization to Pru p 7 is associated with SR and anaphylaxis. To predict the severity of peach fruit allergy, it is useful to assess sIgE Ab reactions combining Pru p 1, 4, and 7.

Hydrophobic pure-silica *BEA-type zeolite membranes with large pores were prepared on tubular silica supports by hydrothermal synthesis using a secondary growth method and were applied to the separation of alcohol/water mixtures by pervaporation (PV), an alternative energy-efficient process for production of biofuels. Amorphous pure-silica tubular silica supports, free of Al atoms, were used for preparing the membranes. In this study, the effects of the synthesis conditions, such as the H2O/SiO2 and NH4F/SiO2 ratios in the synthetic gel, on the membrane formation process and separation performance were systematically investigated. The successfully prepared dense and continuous membranes exhibited alcohol selectivity and high flux for the separation of ethanol/water and butanol/water mixtures. The pure-silica *BEA membranes obtained under optimal conditions (0.08SiO2:0.5TEAOH:0.7NH4F:8H2O) showed high PV performance with a separation factor of 229 and a flux of 0.62 kg&middot, m&minus, 2&middot, h&minus, 1 for a 1 wt % n-butanol/water mixture at 318 K. This result was attributed to the hydrophobicity and large pore size of the pure-silica *BEA membrane. This was the first successful synthesis of hydrophobic large-pore zeolite membranes on tubular supports with alcohol selectivity, and the obtained results could provide new insights into the research on hydrophobic membranes with high permeability.

This paper describes a case of anaphylaxis due to latex exposure during surgery. Allergic reactions to latex during surgery have been described in spinal bifida patients. The case presented in our manuscript is a 15-year old girl who experienced an anaphylactic reaction during her 12th surgery of giant hairy nevus on the thigh. She had a history of oral pruritus after ingestion of chestnut suggesting latex-fruit syndrome. Specific IgE was positive to latex and the allergen components Hev b 1, 3, 5 and 6.02. The diagnosis was latex-allergy due to sensitization obtained after multiple surgeries, possibly due to the contact of latex-containing gloves. Anaphylactic shock during surgery due to NRL allergy is being reported continuously. To prevent allergic reactions during surgery in patients who undergo multiple surgeries, not only in Spina Bifida (SB) patients, frequent analyses of specific IgE to NRL are essential as well as the documentation of the clinical history after ingestion of latex-fruit syndrome related foods. Measurement of specific IgE to allergen components from NRL might be useful in the diagnosis of NRL allergy and in the investigation of the route of NRL sensitization.

Due to its shape selective properties, the narrow pore chabazite zeolite is an interesting material for the separation and purification of 1-butanol from ABE (acetone-butanol-ethanol) fermentation broth, as it selectively traps ethanol from the mixture of acetone, ethanol and butanol. In order to improve the separation performance of chabazite zeolite in humid conditions, we synthesized a core-shell structured chabazite type zeolite, with a chabazite aluminosilicate core coated with a pure silica chabazite layer. This material was evaluated in the vapor phase separation of 1-butanol using a model ABE vapor mixture. Unexpectedly, a broader breakthrough profile of ethanol was obtained on the coated chabazite, resulting in a lower 1-butanol recovery. It was found that the adsorption rate of 1-butanol was decreased by the pure silica chabazite coating. In breakthrough experiments, the coated chabazite showed an even more pronounced exclusion of 1-butanol as compared to the parent material, resulting in a larger separation factor of ethanol over 1-butanol. The pure silica chabazite coating layer acts as a kind of diffusion barrier against 1-butanol rather than ethanol, enhancing the molecular sieving effect.

Background To evaluate the frequency of wheezing in infants, the presence of wheezing was examined in normal infants using a breath sound analyzer, METHODS: A total of 443 infants (age range, 3-24 months) were included in the present study. The existence of audible wheezing and faint wheezing/inaudible wheezing-like noises (FW) was confirmed on chest auscultation and a sound spectrogram. The breath sound parameters of the sound spectrum, frequency limiting 99% of power spectrum (F99 ), roll-off from 600 to 1,200 Hz (slope) and spectrum curve indices, total area under the curve of dB data (A3 /AT and B4 /AT ), and ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF50 and RPF75 ) were calculated. Using an original Japanese questionnaire, we examined the characteristics of the airway condition of all infants. Results Finally, a total of 398 infants were analyzed in the present study, and 283 were in good health while 115 had acute respiratory infection (ARI) in the last 7 days. No infants had audible wheezing on auscultation. Three infants without ARI (1.1%) and 10 infants with ARI (8.7%) had FW. In the evaluation of breath sound parameters, there were no marked differences between the infants with and without FW. Conclusions Using a breath sound analyzer, wheezing and FW were recognized in only a few infants in good health. Infants recognized to have audible wheezing in daily practice may be at risk of developing recurrent wheezing/asthma.

We have synthesized MFI type ferrisilicate zeolite (Fe-MFI) nanocrystals with a crystal size smaller than 100 nm by a dry gel conversion (DGC) method using a sole template (tetrapropylammonium hydroxide). The crystal size of Fe-MFI synthesized by the DGC method was much smaller than that of Fe-MFI synthesized by a conventional hydrothermal synthesis (HTS) method despite using the same precursor solution. The catalytic performance of the nano-sized Fe-MFI in methanol to olefin (MTO) reactions was investigated. The Fe-MFI catalysts showed higher propylene to ethylene (P/E) ratios and lower light paraffin yields compared with MFI type aluminosilicate zeolites (Al-MFI) for both the synthesis methods. In addition, nano-sized Fe-MFI showed a higher P/E ratio (ca. 30) and a longer catalyst lifetime than macro-sized Fe-MFI synthesized by the HTS method.

Zeolites have been widely applied as sophisticated solid acid catalysts in chemical industries. Tuning the acidic properties of zeolites is very important to improve their catalytic performances and expand their utilization. Herein, we synthesized AEI-type Ge-incorporated aluminophosphate, GeAPO-18, by a dry gel conversion method in order to generate new acidity. GeAPO-18 had weaker Bronsted acid sites than the conventional SAPO-18. To confirm the effect of the substitution of Ge, we carried out the methanol to olefin (MTO) reaction over GeAPO-18 and the conventional SAPO-18. The catalyst lifetime of GeAPO-18 in the MTO reaction was longer than that over the conventional SAPO-18. The rate of coke deposition on GeAPO-18 was slower than that on the conventional SAPO-18. These results indicated that the decreased acid strength of GeAPO-18 could retard the coke formation via undesired successive reactions. The incorporation of Ge into the aluminophosphate zeolite framework was a crucial method for tuning the acid strength, which provides a new direction for the design of solid acid catalysts.

A hydrophobic pure-silica *BEA-type zeolite membrane was prepared using the steam-assisted conversion (SAC) method on a seeded tubular silica support coated with dilute synthetic gel. This study systematically investigates the effects of the synthetic conditions on the membrane formation process and separation performance. Under the optimized conditions, when using a dilute synthetic gel with a H2O/SiO2 ratio of 500, a dense and continuous membrane layer was formed in 24 h. This was attributed to dissolution of the surface of the silica support during the steaming process, which functions as a silica source for the growth of a seed crystal layer. An increase in silica the concentration on the support surface locally enabled the formation of a membrane under the dilute synthetic gel composition. The obtained membrane exhibited selectivity toward n-butanol, in addition to a high flux with a separation factor of 132 and a flux of 1.00 kg m−2h−1 for a 1 wt% n-butanol/water mixture at 318 K. This novel simple membrane formation method combines a dilute synthesis gel with SAC, takes advantage of the dissolution of a silica support, and reduces the consumption and cost of chemical raw materials used for membrane synthesis.

Silicalite-1 membranes with high pervaporation performance were prepared successfully on a silica-particle-coated tubular silica support using a gel-free steam-assisted conversion (SAC) method. The effects of the silica-particle layer formed on the top surface of the silica support and the physical properties of the silica particles themselves on the membrane-formation process were investigated. The silica particles coated served as the additional silica source for growing the silicalite-1 seed crystal layer into the silicalite-1 membrane. As a result, it was possible to form a dense and continuous membrane even under gel-free conditions. Furthermore, it was found that the properties of the silica particles, such as their primary particle diameter, had a determining effect on their solubility during the steam treatment, that is, on the supply rate of the silica source. The silicalite-1 membrane obtained using the spherical-silica-particle-coated support had an approximately 9-&mu, m-thick separation layer and showed very high pervaporation performance, exhibiting a separation factor of 105 and a flux of 3.72 kg m&minus, 2 h&minus, 1 for a 10 wt % ethanol/water mixture at 323 K. Thus, the gel-free SAC method can be used with a silica support coated with silica particles to readily prepare high-performance membranes without producing any chemical waste.

Childhood Guillain-Barre syndrome (GBS) occasionally leads to respiratory failure early after onset, requiring long-term ventilation management after tracheal intubation. However, patients requiring tracheostomy management are rare. In the present study, a case of a 12-year-old boy with GBS who required artificial respiration management due to rapid progression of respiratory muscle paralysis is reported. Intravenous immunoglobulin (IVIg) and pulse steroid therapy were provided; however, both were ineffective and tracheostomy was necessary 26 days after onset. A second course of IVIg and pulse steroid therapy was administered on day 34. With continued rehabilitation, the patient was able to walk long distances on day 74 and was subsequently discharged on day 89. In cases of severe GBS, when IVIg and pulse steroid therapy do not improve the respiratory muscle strength of the patient, early tracheostomy may improve the patient's quality of life during artificial respiration management.

ZIF-8 is a flexible zeolitic imidazole-based metal organic framework whose narrow pore apertures swing open by reorientation of imidazolate linkers and expand when probed with guest molecules. This work reports on the crystal size dependency of both structural transitions induced by N-2 and Ar adsorption and dynamic adsorption behavior of n-butanol using well-engineered ZIF-8 crystals with identical surface area and micropore volume. It is found that the crystal downsizing of ZIP-8 regulates the structural flexibility in equilibrium adsorption and desorption of N-2 and Ar. Adsorption kinetics of n-butanol in ZIF-8 are strongly affected by the crystal size, however, not according to a, classical intracrystalline diffusion, mechanism. Our results suggest that Structural transitions and transport properties are dominated by crystal surface effects. Crystal downsizing increases the importance of such surface barriers.

Among the increasingly popular zeolites with eight-membered ring channels, CHA-type zeolites are considered to have great potential for various applications such as catalysis and separation. While CHA-type aluminosilicates with Si/Al ratios below 100 can be synthesized in both hydroxide and fluoride media, to date, pure silica CHA-type zeolites can only be prepared in a fluoride medium, with a low H 2 O/SiO 2 of 3. Herein, we investigated the effect of various synthesis conditions on the formation of pure silica CHA-type zeolites. Single phase crystalline pure silica CHA was synthesized within a very narrow range of H 2 O/SiO 2 ratio, and small deviations in the water content from this range led to the formation of STT-type zeolites. High N , N , N -trimethyl-1-adamant ammonium fluoride/SiO 2 ratios allowed the formation of pure silica CHA, with no by-products, in the synthesis gel, with a high H 2 O/SiO 2 ratio of 8. Additionally, synthesis conditions, in particular the H 2 O/SiO 2 ratio, significantly influenced the specific surface and pore volume of CHA.

MFI type galloaluminosilicates (GaAlMFI) were coated with inert silicalite-1 layers. The silicalite-1 coating could improve the para-selectivity for xylene production in aromatization of propane. In the silicalite-1 coating step, low alkali concentration in the synthesis solution enhanced para-selectivity. A proton-exchange procedure also had an impact on the para-selectivity. Significant decrease of para-selectivity was observed over the silicalite-1 coated GaAlMFI with repeated proton-exchange. From the 71Ga and 27Al MAS NMR measurements, demetalation occurred during the proton-exchange process, and those metal species is likely to become catalytically active sites without para-selectivity. From the aromatization of propane and n-butane, para-selectivity in n-butane aromatization was found to be higher than that in propane aromatization. From the product distribution, naphthalene and its derivatives were easier to be produced in propane aromatization compared to n-butane aromatization. The formation of naphthalene and its derivatives may relate to decrease in the para-selectivity in propane aromatization.

Dehumidification in CO

The catalytic activity of metal cation doped Ru/CeO2/Al2O3 as pre-reforming catalysts for steam reforming of desulfurized kerosene was investigated at a moderate temperature. The oxygen storage capacity (OSC) was significantly improved by Tb and Zr doping. The improved OSC by doping metal cations was found to increase the conversion of desulfurized kerosene to C1 products. Tb doping into CeO2, in particular, could achieve the highest OSC and catalytic activity. The initial conversion of desulfurized kerosene was approximately 80% and deactivation was observed over Ru/CeO2/Al2O3 with S/C = 3 at 873 K. In contrast, Ru/Ce0.8Tb0.2O2/Al2O3 exhibited the complete conversion of desulfurized kerosene to C1 products and stable catalytic performance at the same reaction condition. The Tb doping could inhibit the deactivation and increase the catalytic activity for degradation of long chain hydrocarbons and aromatics.

A highly oriented UiO-66 film, with a monocrystalline layer, was successfully prepared by the solvothermal method. Acetic acid, which served as a modulator, was essential to achieve high film orientation. Water played an important role in promoting the intergrowth of UiO-66 crystals.

Students of the Tohoku University School of Medicine experienced the Great East Japan Earthquake on March 11, 2011. We conducted a series of surveys to examine the relationships among their experiences and activities on the day of the earthquake, their physical, mental, and economic problems following the disaster, and how their problems changed over time. The initial survey was performed in April 2011, with three follow-up surveys in July 2011, February 2012, and April 2013. The initial survey focused on students' experiences and living conditions during the disaster, which contained questions on their locations and circumstances, family circumstances, lives after the earthquake, voluntary works, physical or mental health problems, and desire for counseling. The follow-up surveys included new items regarding their circumstances, changes in their health problems, and their desire for economic assistance. Students who answered the first survey to the 4th one, with response rates in the following bracket, were as follows: 472 (28.0%), 640 (29.9%), 681 (36.0%), and 678 (39.0%), respectively. Six months after the earthquake, about 20% having experienced physical and/or mental problems. Although there was a trend toward a reduction in suffering and health problems over time, some students' conditions remained unchanged or worsened. It is notable that students who had participated in voluntary activities, despite their own suffering of harm and distress, were identified as the group that required the closest attention. Our present results can be applied to appropriate supports for students in future large-scale disasters. Language: en

In this study, we present a new concept in chemically stabilized ionic liquid membranes: an ionic liquid organosilica (ILOS) membrane, which is an organosilica membrane with ionic liquid-like properties. A silylated ionic liquid was used as a precursor for synthesis. The permselectivity, permeation mechanism, and stability of the membrane in the H2/toluene binary system were then compared with a supported ionic liquid membrane. The membrane showed a superior separation factor of toluene/H2 (>17,000) in a binary mixture system based on a solution–diffusion mechanism with improved durability over the supported ionic liquid membrane.

In this study, we present a new concept in chemically stabilized ionic liquid membranes: an ionic liquid organosilica (ILOS) membrane, which is an organosilica membrane with ionic liquid-like properties. A silylated ionic liquid was used as a precursor for synthesis. The permselectivity, permeation mechanism, and stability of the membrane in the H2/toluene binary system were then compared with a supported ionic liquid membrane. The membrane showed a superior separation factor of toluene/H2 (>17,000) in a binary mixture system based on a solution–diffusion mechanism with improved durability over the supported ionic liquid membrane.

A macro-/mesoporous Co-N-C-decorated separator is proposed to confine and reutilize migrating polysulfides. Endowed with a desirable structure and synchronous lithio- and sulfiphilic chemistry, the macro-/mesoporous Co-N-C interface manipulates large polysulfide adsorption uptake, enabling good polysulfide adsorption kinetics, reversible electrocatalysis toward redox of anchored polysulfides, and facile charge transport. It significantly boosts the performance of a simple 70 wt % S/MWCNTs (MWCNTs=multi-walled carbon nanotubes) cathode, achieving high initial capacities (e.g., 1406 mAh g-1 at 0.2C, 1203 mAh g-1 at 1C), nearly 100 % Coulombic efficiencies, and high reversible capacities after cycle tests (e.g., 828.4 mAh g-1 at 1C after 100 cycles) at both low and high current rates. These results demonstrate that decorating separator with macro-/mesoporous Co-N-C paves a feasible way for developing advanced Li-S batteries.

Combination of the reactions by means of membrane separation techniques are of interest. The CO2 methanation was combined with NH3 decomposition by in situ H2 separation through a Pd membrane. The CO2 methanation reaction in the permeate side was found to significantly enhance the H2 removal rate of Pd membrane compared to the use of sweep gas. The reaction rate of CO2 methanation was not influenced by H2 supply through the Pd membrane in contrast to NH3 decomposition in the retentate side. However, the CH4 selectivity could be improved by using a membrane separation technique. This would be caused by the active dissociated H species which might immediately react with adsorbed CO species on the catalysts to CH4 before those CO species desorbed. From the reactor configuration tests, the countercurrent mode showed higher H2 removal rate in the combined reaction at 673 K compared to the cocurrent mode but the reaction rate in CO2 methanation should be improved to maximize the perfomance of membrane reactor.

Zeolites have been applied in various chemical processes due to their multi-functionality. In practical use of zeolites, their hydrothermal stability is one of the important factors. We focused on the coating with hydrophobic silicalite-1, which is all silica MFI zeolite. In this work, we investigated the hydrothermal stability of ZSM-5 (MFI type aluminosilicate zeolite) coated with silicalite-1 (all silica MFI zeolite) by the combination of steam treatment and NH3 temperature programed desorption (NH3-TPD). The peak area at higher temperature (h-peak area) in NH3-TPD profiles for core-shell MFI zeolite (ZSM-5/s-1) was unchanged even after steam treatment for 8 h in contrast to uncoated ZSM-5. These results strongly indicate that extremely high Si/Al ratio on the external surface coated with silicalite-1 is highly effective for improving the hydrothermal stability; the hydrophobicity of silicalite-1 probably prevents the penetration of steam into Al sites of ZSM-5. This work opens up a new function of the silicalite-1 layer on ZSM-5 other than improvement of shape selectivity.

In this study, silicalite-1 membranes were prepared on seeded tubular silica supports using a gel-free steam-assisted conversion (SAC) method. The effects of seed crystal type on the growth and microstructure of the membranes were investigated. The morphologies of the membranes obtained by this preparation method reflected the orientation of the seed crystal layer covering the tubular support; when spherical seed crystals were used, the membrane surface was composed of randomly oriented crystals; whereas when coffin-type seed crystals were used, the membrane surface was composed of crystals arranged in a relatively b-axis orientation. This suggests that membrane layers can be grown with the same orientation as the seed crystals on the tubular support. That is, the gel-free SAC method is able to suppress changes in the orientation of zeolite crystals during membrane formation, which is a problem in conventional hydrothermal syntheses. This is a very interesting phenomenon that occurs only under gel-free SAC conditions, and accounts for the successful growth of the b-oriented silicalite-1 membrane layer on the tubular support. Our findings successfully demonstrate approaches for the formation of membrane layers that retain the orientation of zeolite seed crystals on tubular supports, and for the synthesis of oriented zeolite membranes with high permeability.

Stainless-steel, Ni, Cr and Fe particles were adhered on Pd and Pd alloy membranes in order to investigate an effect of alloying of such metal components and membranes to the membrane performance. The adhesion of metal particles to Pd and Pd alloy membranes were evaluated through the thermal treatment. Cracks were observed along the metal particles on Pd and Pd–Ag membranes by alloying between the membranes and metal particles. For Ni and Cr, the crack formation was caused by the Kirkendall effect. For Fe, that should be attributed to the Kirkendall effect or the phase transition of Pd–Fe alloys. In contrast, it was found that Pd–Ni and Pd–Fe binary alloy membranes prevented the crack formation because alloying of Pd with appropriate metals could control the interdiffusion between Pd alloy membranes and adhered metal particles.

The synthesis of a novel layered silicate SSA-1 (SSA: silicate synthesized with a quaternary amine) was achieved in the SiO2-H2O-TEAOH (TEAOH: tetraethylammonium hydroxide – as an organic structural directing agent) system. The crystal structure of SSA-1 involved two silicate layers composed of bre [10T]-type CBU (Composite Building Unit) and TEAOH in interlayers. The topotactic transformation of SSA-1 by calcination was examined, resulting in a porous material (PML-1: porous material transformed from a layered silicate) with a 108 m2 g−1 BET surface area and 0.035 cm3 g−1 pore volume. PML-1 is a siliceous microporous material with silanols in the framework and possesses unique properties, such as hydrophilicity, in spite of all its silica composition. The most reasonable crystal structure of PML-1 was successfully determined on the basis of the crystal structure of SSA-1 by a combination of manual modelling, PXRD pattern simulation, DFT optimization and Rietveld analysis. Additionally, an interlayer expanded siliceous zeolite SSA-1 (IEZ-SSA-1) was also successfully prepared by silylation using trichloro(methyl)silane under acidic conditions. IEZ-SSA-1 showed hydrophilicity or hydrophobicity properties by changing the functional group of the pillar part in the interlayer. Additionally, IEZ-SSA-1 showed a large gas adsorption property (537 m2 g−1 and 0.21 cm3 g−1).

Catalytic properties of the 75 nm and 0.8 μm-sized SAPO-34 crystals on acetone-to-olefins (ATO) reaction were compared. The 75 nm-sized crystals (nanocrystals) showed longer catalyst lifetime than 0.8 μm-sized crystals, and products selectivity was similar for the two SAPO-34 catalysts, as is the case in methanol-to-olefins (MTO) and dimethyleter-to-olefins (DTO) reactions. The reaction site of ATO reaction over SAPO-34 was studied using coke-deposited SAPO-34 as catalysts whose pores are deactivated through the DTO reaction. The reason for longer catalyst lifetime of the nanocrystals in the ATO reaction must be a large surface area of the SAPO-34 nanocrystals, unlike in the case of the MTO and DTO reactions.

The emergence of drug-resistant bacteria is a severe problem in aquaculture. The ability of drug resistance genes to transfer from a bacterial cell to another is thought to be responsible for the wide dissemination of these genes in the aquaculture environment; however, little is known about the gene transfer mechanisms in marine bacteria. In this study, we show that a tetracycline-resistant strain of Photobacterium damselae subsp. damselae, isolated from seawater at a coastal aquaculture site in Japan, harbors a novel multiple drug resistance plasmid. This plasmid named pAQU1 can be transferred to Escherichia coli by conjugation. Nucleotide sequencing showed that the plasmid was 204,052 base pairs and contained 235 predicted coding sequences. Annotation showed that pAQU1 did not have known repA, suggesting a new replicon, and contained seven drug resistance genes: blaCARB-9-like, floR, mph(A)-like, mef(A)-like, sul2, tet(M) and tet(B). The plasmid has a complete set of genes encoding the apparatus for the type IV secretion system with a unique duplication of traA. Phylogenetic analysis of the deduced amino acid sequence of relaxase encoded by traI in pAQU1 demonstrated that the conjugative transfer system of the plasmid belongs to MOBH12, a sub-group of the MOBH plasmid family, closely related to the IncA/C type of plasmids and SXT/R391 widely distributed among species of Enterobacteriaceae and Vibrionaceae. Our data suggest that conjugative transfer is involved in horizontal gene transfer among marine bacteria and provide useful insights into the molecular basis for the dissemination of drug resistance genes among bacteria in the aquaculture environment.