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The phase inversion procedure was used to prepare Al2O3 ceramic hollow fiber substrates (AlCHFS) utilizing the dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAC), and 1-methyl-2-pyrrolidone (NMP) aprotic solvents. Different aprotic solvent and non-solvent (water) interactions were used to calibrate different ceramic oxide substrates. AlCHFS with an asymmetrical structure consisting of a finger-like structure on the lumen side and a pore structure on the shell side was obtained using an aprotic solvent/non-solvent pair with a high total Hildebrand solubility (δt). As the aprotic strength was reduced, the finger-like structure on the shell sides became more prominent. Hydrogen permeation studies conducted between 350°C and 450°C reveal that the Pd-coated AlCHFS produced from DMAC aprotic solvent has the maximum hydrogen flux (~0.24 mol m−2 s−1). The activation energy for the thermally activated hydrogen transport process through the Pd-coated AlCHFSs is determined to be around 11.06–14.61 kJ mol−1 in the temperature range of 350°C to 450°C, and it increases linearly with increasing surface porosity of ceramic oxide substrate.

This study successfully prepared and tested sulfur- and nitrogen-co-doped TiO2-coated α-Al2O3 (S,N-doped TiO2/Al2O3) hollow fiber (HF) membranes for efficient photocatalytic degradation of gaseous ammonia (NH3). Thiourea was used as a sulfur- and nitrogen-doping source to produce a S,N-doped TiO2 photocatalyst powder. For comparative purposes, undoped TiO2 powder was also synthesized. Through the application of a phase-inversion technique combined with high-temperature sintering, hollow fibers composed of α-Al2O3 were developed. Undoped TiO2 and S,N-doped TiO2 photocatalyst powders were coated on the α-Al2O3 HF surface to obtain undoped TiO2/Al2O3 and S,N-doped TiO2/Al2O3 HF membranes, respectively. All prepared samples were characterized using XRD, TEM, XPS, UV-Vis, SEM, BET, FT-IR, and EDS. S and N dopants were confirmed using XPS and UV-Vis spectra. The crystal phase of the undoped TiO2 and S,N-doped TiO2 photocatalysts was a pure anatase phase. A portable air purifier photocatalytic filter device was developed and tested for the first time to decrease the amount of indoor NH3 pollution under the limits of the lachrymatory threshold. The device, which was made up of 36 S,N-doped TiO2/Al2O3 HF membranes, took only 15–20 min to reduce the level of NH3 in a test chamber from 50 ppm to around 5 ppm, confirming the remarkable performance regarding the photocatalytic degradation of gaseous NH3.

Due to its greater physical–chemical stability, ceramic nanofiltration (NF) membranes were used in a number of industrial applications. In this study, a novel NF membrane was prepared by co-depositing a titanium dioxide (TiO2) and graphene oxide (GO) composite layer directly onto a porous α-Al2O3 hollow fiber (HF) support. An 8 µm-thick TiO2/GO layer was deposited to the surface of α-Al2O3 HF support by vacuum deposition method to produce advanced TiO2/GO-Al2O3 HF NF membrane. Scanning electron microscope (SEM) micrographs, energy dispersive spectrometer (EDS), X-ray powder diffraction (XRD), thermogravimetric analyzer (TGA), porosity, 3-point bending strength, zeta potential analysis, and hydrophilic properties by water contact angle are used for TiO2/GO-Al2O3 HF NF membrane characterization. The results show that the developed membrane’s MWCO ranged from 600 to 800 Da. The water flux, rejection of lignin, and sodium ions were 5.6 L/m2 h·bar, ~92.1%, and ~5.5%, respectively. In a five-day NF process, the TiO2/GO-Al2O3 HF NF membrane exhibits good lignin permeation stability of about 14.5 L/m2 h.

In recent years, reactive ammonia (NH3) has emerged as a major source of indoor air pollution. In this study, Al2O3-based hollow fiber membranes functionalized with nitrogen-doped titanium dioxide were produced and successfully applied for efficient heterogeneous photocatalytic NH3 gas degradation. Al2O3 hollow fiber membranes were prepared using the phase inversion process. A dip-coating technique was used to deposit titanium dioxide (TiO2) and nitrogen-doped titanium dioxide (N-TiO2) thin films on well-cleaned Al2O3-based hollow fiber membranes. All heterogeneous photocatalytic degradation tests of NH3 gas were performed with both UV and visible light irradiation at room temperature. The nitrogen doping effects on the NH3 heterogeneous photocatalytic degradation capacity of TiO2 were investigated, and the effect of the number of membranes (30, 36, 42, and 48 membranes) of the prototype lab-scale photocatalytic membrane reactor, with a modular design, on the performances in different light conditions was also elucidated. Moreover, under ultraviolet and visible light, the initial concentration of gaseous NH3 was reduced to zero after only fifteen minutes in a prototype lab-scale stage with a photocatalytic membrane reactor based on an N-TiO2 photocatalyst. The number of Al2O3-based hollow fiber membranes functionalized with N-TiO2 photocatalysts increases the capacity for NH3 heterogeneous photocatalytic degradation.

There is little knowledge regarding the exchange of academic information on religious contexts. The objective of this informational study was to perform an overall analysis of all Buddhism-related communications collected in the Web of Science (WoS) from 1993 to 2011. The studied informational parameters include the growth in number of the scholarly communications, as well as the language-, document-, subject category-, source-, country-, and organization-wise distribution of the communications. A total of 5407 scholarly communications in this field of study were published in the selected time range. The most preferred WoS subject category was Asian Studies with 1773 communications (22.81%), followed by Religion with 1425 communications (18.33%) and Philosophy with 680 communications (8.75%). The journal with the highest mean number of citations is Numen: International Review for the History of Religions—with 2.09 citations in average per communication. The United States was the top productive country with 2159 communications (50%), where Harvard University topped the list of organization with 85 communications (12%).

The present review seeks to take stock of the South Korean publication activity on the field of chemistry by analyzing systematically all chemistry-related scholarly communications collected in the Web of Science (WOS) database published by at least one Korean author or Korean institute- or university-affiliated author from 1993 to 2012. The studied parameters included the growth in number of the communications, as well as the language-, document-, category-, source-, organization-, and collaboration-wise distribution of the South Korean communications. A total of 5660 communications on chemistry were found to be published by South Korean researchers during the aforementioned period of time, and South Korea was the 15th country (1.77%) in the world in terms of informational communication activity in chemistry.

In today’s economy, one of the most important national indicators of economic growth performance is the country’s ability to produce new technology—and use it responsibly and efficiently—for environmental protection or energy conservation, production and consumption in agreement with international standards. The purpose of this study is to identify the Research and Development (R&D) capability in the area of environmentally friendly technologies in China, Japan and Korea over the last twenty years. As the field is very wide, Water-Gas Shift (WGS) reaction technologies were taken as a case study for the purpose of this article. During 1990–2011 a total of 788 papers in the field of WGS technologies were published by scientists in China, Japan and Korea. China was the top producing country with 394 papers (50%) followed by Japan with 250 papers (32%), and Korea with 144 papers (18%). The growth of the literature in the field was found to be exponential in nature for China. The R&D capabilities were found to correlate directly with the Gross Domestic Expenditures on R&D (GERD), Researchers in Full-time equivalents (FTE), and other economic parameters.