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Adsorption uptake of Philippine natural zeolite for Zn2+ ions in aqueous solution

Journal of Physics: Conference Series 2019年第1期1191卷

作者： M B Gili L Olegario-Sanchez M Conato Material Science and Engineering Program College of Science University of the Philippines Diliman Quezon City 1101 Philippines Philippine Nuclear Research Institute – Department of Science and Technology Commonwealth Avenue Diliman Quezon City 1101 Philippines Department of Mining Metallurgical and Materials Engineering College of Engineering University of the Philippines Diliman Quezon City 1101 Philippines Institute of Chemistry University of the Philippines Diliman Quezon City 1101 Philippines

The Philippine natural zeolite (PNZ) was characterized and subjected to Zn2+ adsorption tests in aqueous solutions to determine its adsorption uptake and to understand its adsorption behaviour. The PNZ was characterized using XRD, SEM, BET-analysis and TG-DTA. XRD showed significant peaks indexed to natural mordenite-type zeolite along with other natural zeolites and minerals. SEM micrographs revealed a rough and corrugated surface morphology of the sample. BET physisorption analysis showed a surface area of 222.63 m2/g. From the analytical tests report given by the supplier, the Si/Al ratio (SAR) was computed to be equal to 4.29 based on the silica and alumina content of the PNZ. Adsorption kinetic and thermodynamic studies were done to determine the adsorption mechanism and adsorption capacity of PNZ for Zn2+ ions in aqueous solution. From the adsorption kinetic curve, the PNZ attained chemical equilibrium after 50 min. Pseudo-second-order kinetic model was the most applicable kinetic model providing the highest correlation with the data. Langmuir model better described the adsorption isotherm of the PNZ than Freundlich model. The theoretical maximum cation exchange capacity of PNZ was computed as 27.17 mg Zn2+/g according to the Langmuir model.

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Synthesis and Electrochromic Properties of Polyimides with Pendent Benzimidazole and Triphenylamine Units

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Chinese Journal of Polymer science 2016年第9期34卷 1091-1102页

作者： Wan-an Cai Ji-wei Cai 牛海军 Tian-di Xiao Xu-duo Bai Cheng Wang 张艳红 Wen Wang Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationDepartment of Macromolecular Science and EngineeringSchool of ChemicalChemical Engineering and MaterialsHeilongjiang UniversityHarbin 150086China School of Material Science and Engineering Harbin Institute of TechnologyHarbin 150080China

Five novel near-infrared electrochromic aromatic polyimides （PIs） with pendent benzimidazole group were synthesized from 4,4＇-diamino-4＂-（1-benzylbenzimidazol-2-yl）triphenylamine （named as DBBT） with five different dianhydrides via two-step polymerization process, respectively. The maximum UV-Vis absorption bands of these PIs locate at about 335 nm for solid films due to the π-π＊ transitions. A reversible pair of distinct redox peaks, that were associated with a noticeable color change from original yellow to blue, was observed in the cyclic voltammetry （CV） test. A new absorption peak emerged at 847 nm in near-infrared （NIR） region with increasing voltage in UV-Vis-NIR spectrum, which indicates that PI can be used as NIR electrochromic material. These novel PIs have good electrochemical stability, appropriate energy levels for the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO）, in the range of-5.17 eV to -5.20 eV and -2.14 eV to -2.26 eV （versus the vacuum level） determined by cyclic voltammetry method. These values basically consisted with the results of quantum chemical calculation. These polyimides can be used as novel electrochromic and hole transportation materials.

关键词： Triphenylamine Electrochromic Benzimidazole Polyimide Near-infrared.

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Signatures of electronic nematicity in (111) LaAlO3/SrTiO3 interfaces

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Physical Review B 2018年第4期97卷 041408(R)-041408(R)页

作者： S. Davis Z. Huang K. Han Ariando T. Venkatesan V. Chandrasekhar Graduate Program in Applied Physics and Department of Physics and Astronomy Northwestern University 2145 Sheridan Road Evanston Illinois 60208 USA NUSNNI-Nanocore National University of Singapore 117411 Singapore Department of Physics National University of Singapore 117551 Singapore NUS Graduate School for Integrative Sciences & Engineering National University of Singapore 117456 Singapore Department of Electrical and Computer Engineering National University of Singapore 117576 Singapore Department of Material Science and Engineering National University of Singapore 117575 Singapore

The two-dimensional conducting gas (2DCG) that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) has been widely studied due to the multitude of in situ tunable phenomena that exist at the interface. Recently it has been shown that nearly every property of the 2DEG that forms at the interface of (111) oriented LAO/STO is strongly anisotropic with respect to the in-plane crystal direction. This in-plane rotational symmetry breaking points to the existence of an electronic nematic phase at the interface that can be modified by an in situ electrostatic back-gate potential. Here we show that the onset temperature of the anisotropy in the longitudinal resistance is T≈22K, which does not match up with any known structural transition, and coincides with the onset of anisotropy in the Hall response of the system. Furthermore, below 22 K, charge transport is activated in nature with different activation energies along the two in-plane crystal directions. Such a response implies that the band edges along the two directions are different and provides further evidence of an electronic nematic state at the interface.

关键词： Electrical properties Hall effect Nematic order Transport phenomena Hall bar Resistivity measurements Transport techniques

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Correction: Multifunctional polyurethanes synthesized from different triarylamine units with electrochromic, photogeneration, memory storage and sensing properties

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New Journal of Chemistry 2019年第5期43卷 2411-2411页

作者： Xu Zhang Qingyi Lu Caiyu Yang Shuo Zhao Yan Wang Wei Zhang Haijun Niu Ping Zhao Wen Wang Jinghe Fan Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Department of Macromolecular Science and Engineering School of Chemical Chemical Engineering and Materials Heilongjiang University Harbin 150080 P. R. China Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology Shanghai 20037 P. R. China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150080 P. R. China

Correction for ‘Multifunctional polyurethanes synthesized from different triarylamine units with electrochromic, photogeneration, memory storage and sensing properties’ by Xu Zhang et al., New J. Chem., 2019, 43, 1...

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Synthesis and characterization of mordenite-type zeolites via hydrothermal method using silica gel and sodium aluminate as Si and Al sources at varying temperature

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Journal of Physics: Conference Series 2019年第1期1191卷

作者： M Gili M Conato Material Science and Engineering Program College of Science University of the Philippines Diliman Quezon City 1101 Philippines Philippine Nuclear Research Institute – Department of Science and Technology Commonwealth Avenue Diliman Quezon City 1101 Philippines Institute of Chemistry University of the Philippines Diliman Quezon City 1101 Philippines

Mordenite-type zeolites were prepared via hydrothermal method using silica gel and sodium aluminate as Si and Al sources respectively. The temperature was varied from 150 °C up to 190 °C to determine the minimum temperature to obtain crystalline mordenite using a 23 mL Teflon-lined stainless-steel autoclave. The samples were characterized using XRD, FTIR and SEM. With the given experimental conditions, mordenite-type zeolites with good crystallinity and excellent purity were produced at 190 °C. Amorphous materials with notable peaks that correspond to mordenite planes were produced at 170 °C. The sample produced at 150°C was completely amorphous. FTIR revealed that all the three samples contain bands associated to aluminosilicate vibrational groups. However, a significant decrease in the intensities of vibration bands associated to hydroxyl (HO−) stretching and water bending were observed as the temperature is decreased. From the SEM, the sample treated at 190°C was composed of particles with strikingly linear edges having an average grain size of ~38.0 µm. Most particles are hexagonal in shape. Particle components of the samples synthesized at 170 °C and 150 °C have irregular sizes and shapes.

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Morphology and crystal-plane effects of Zr-doped CeO2 nanocrystals on the epoxidation of styrene with tert-butylhydroperoxide as the oxidant

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Journal of Energy Chemistry 2017年第4期26卷 681-687页

作者： Jia Ren Xin Liu Ruihua Gao Wei-Lin Dai Department of Chemistry&Shanghai Key Laboratory of Molecular Catalysis and Innovative Material Fudan UniversityShanghai 200433China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

The morphology effect of Zr-doped CeOwas studied in terms of their activities in the selective oxidation of styrene to styrene oxide using tert-butyl hydroperoxide as the oxidant. In the present work, Zrdoped CeOnanorods exhibited the highest catalytic performance（yield of styrene oxide and TOF value）followed by nanoparticles and nanocubes. For the Zr-doped CeOnanorods, the apparent activation energy is 56.3 k J/mol, which is much lower than the values of catalysts supported on nanoparticles and nanocubes（73.3 and 93.4 k J/mol）. The high resolution transmission electron microscopy results indicated that（100） and（110） crystal planes are predominantly exposed for Zr-doped CeOnanorods while（100）and（111） for nanocubes,（111） for nanoparticles. The remarkably increased catalytic activity of the Zrdoped CeOnanorods is mainly attributed to the higher percentage of Cespecies and more oxygen vacancies, which are associated with their exposed（100） and（110） crystal planes. Furthermore, recycling studies proved that the heterogeneous Zr-doped CeOnanorods did not lose its initial high catalytic activity after five successive recycles.

关键词： Morphology effect Zr-doped CeO2 Styrene Selective oxidation Oxygen vacancies

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Morphology and filtration performances of polyether sulfone membrane modified with carbon and Fe2O3

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IOP Conference Series: materials science and engineering 2020年第1期845卷

作者： R. Arisandi A Fathurrahman A. Fahrina F Razi Z Jalil N Arahman Department of Chemical Engineering Universitas Syiah Kuala Banda Aceh 23111 Indonesia Magister Program of Chemical Engineering Department of Chemical Engineering Universitas Syiah Kuala Banda Aceh 23111 Indonesia Doctor of Engineering Graduate School of Engineering Universitas Syiah Kuala Banda Aceh 23111 Indonesia Material Physics Laboratory Department of Physics Faculty of Mathematics and Natural Science SyiahKuala University Banda Aceh Indonesia Graduate School of Environmental Management Universitas Syiah Kuala Jl. Tgk Chik Pante Kulu No. 5 Darussalam Banda Aceh 23111 Indonesia Research center for environmental and natural resources Universitas Syiah Kuala Jl. Hamzah Fansuri No. 4 Darussalam Banda Aceh 23111 Indonesia Atsiri Research Center Universitas Syiah Kuala Banda Aceh 23111 Indonesia

Membrane separation technology has been widely applied in various industrial sectors. Some modification on membrane composition and structure is conducted to improve membrane filtration performance and mitigate fouling phenomena. Fouling on membrane surfaces lead to decrease permeabilty, increase energy consumtion, and shorten membrane life time. The aim of this study is to manufacture PES membrane which involved inorganic additives consits of Carbon and Fe2O3 particles to mitigate fouling tendency. All of membranes were prepared using phase inversion method with dissolving PES polymer into dimethyl formamide (DMF). The result membranes were characterized using Scanning Electron Microscopy (SEM) to investigate morphological structure and breaking strength to determine mechanical property. Membrane filtration performance were tested using soy protein solution in cross-flow system. The results showed that the addition of inorganic particles in PES membrane caused the increasing of pores which lead to increase pure water flux from 15.14 L/m2.h to 58.67 L/m2.h. Fouling mitigation test towards soy protein also showed that carbon and Fe2O3 particles enhanced membrane flux recovery ratio from 64.5 to 76%. Furthermore, the inorganic particles presence in PES membrane also improved the tensile strength of membrane up to 128 Mpa.

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A Participant-Derived Xenograft Model of HIV Enables Long-Term Evaluation of Autologous Immunotherapies

SSRN

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SSRN 2020年

作者： McCann, Chase D. van Dorp, Christiaan H. Ward, Adam R. Danesh, Ali Dilling, Thomas R. Mota, Talia M. Zale, Elizabeth Patel, Shabnum Brumme, Chanson J. Dong, Winnie Jones, Douglas S. Andresen, Thomas L. Walker, Bruce D. Brumme, Zabrina L. Bollard, Catherine M. Perelson, Alan S. Irvine, Darrell J. Jones, R. Brad Weill Cornell Medicine Belfer Research Building Room 550 413 E 69th Street New YorkNY10021 United States Infectious Diseases Division Department of Medicine Weill Cornell Medical College New YorkNY United States Immunology & Microbial Pathogenesis Graduate Program Weill Cornell Graduate School of Medical Sciences New YorkNY United States Los Alamos National Laboratory Los AlamosNM United States Department of Microbiology Immunology & Tropical Medicine The George Washington University School of Medicine and Health Sciences WashingtonDC United States Milken Institute School of Public Health The George Washington University WashingtonDC United States Center for Cancer and Immunology Research Children’s National Health System WashingtonDC United States GW Cancer Center George Washington University WashingtonDC United States British Columbia Centre for Excellence in HIV/AIDS VancouverBC Canada Repertoire Immune Medicines CambridgeMA United States Ragon Institute of Massachusetts General Hospital MIT & Harvard University BostonMA United States Institute for Medical and Engineering Sciences MIT CambridgeMA United States Howard Hughes Medical Institute Chevy ChaseMD United States Faculty of Health Sciences Simon Fraser University BurnabyBC Canada Department of Material Science and Engineering MIT CambridgeMA United States Koch Institute for Integrative Cancer Research MIT CambridgeMA United States Department of Biological Engineering MIT CambridgeMA United States

HIV-specific CD8 + T-cells partially control viral replication and delay disease progression, but rarely provide lasting protection – largely due to immune escape. We show that engrafting mice with memory CD4+ T-cells from HIV + donors uniquely allows for the in vivo evaluation of autologous T-cell responses, while avoiding graft-versus-host disease and the need for human fetal tissues that limit other models. Treating HIV-infected mice with clinically-relevant HIV-specific T-cell products resulted in substantial reductions in viremia, which were augmented by engineering with IL-15 superagonist-containing nanogels. Ultimately, in vivo activity was limited by the selection of diverse escape mutations, recapitulating patterns seen in humans. By applying mathematical modeling, we show that the kinetics of the CD8 + T-cell response have a profound impact on the emergence and persistence of escape mutations. This ‘participant-derived xenograft’ model of HIV provides a powerful tool for studying HIV-specific immunological responses and facilitating the development of effective cell-based therapies. © 2020, The Authors. All rights reserved.

关键词： T-cells

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In vitro and in vivo models for assessing the host response to biomaterials

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Drug Discovery Today: Disease Models 2017年 24卷 13-21页

作者： Saleh, Leila S. Bryant, Stephanie J. Department of Chemical and Biological Engineering University of Colorado 3415 Colorado Avenue Boulder 80309 CO United States BioFrontiers Institute University of Colorado 3415 Colorado Avenue Boulder 80309 CO United States Material Science and Engineering Program University of Colorado 3415 Colorado Avenue Boulder 80309 CO United States

The foreign body response (FBR) occurs ubiquitously to essentially all non-biological materials that are implanted into higher organisms. The FBR is characterized by inflammation followed by fibrosis and is mediated largely by macrophages. While many current medical devices tolerate the FBR, the FBR is responsible for many asceptic device failures and is hindering advancements of new devices that rely on device-host communication to function. To this end, in vitro and in vivo models are critical to studying how a biomaterial, via its chemistry and properties, affect the FBR. This short review highlights the main in vitro and in vivo models that are used to study the FBR. In vitro models that capture macrophage interrogation of a biomaterial and evaluation of macrophage attachment, polarization and fusion are described. In vivo models using rodents, which provide a relatively simple model of the complex FBR process, and human-relevant nonhuman primate models are described. Collectively, the combination of in vitro and in vivo models will help advance our fundmental understanding of the FBR and enable new biomaterials to be developed that can effectively modulate the FBR to achieve a desire device-host outcome. © 2018 Elsevier Ltd

关键词： In vivo In vitro Macrophages Immune Response Biocompatible materials Fast nuclear reactors Device Failure

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Cure monitoring and characterization of epoxy/amine networks, modified with 1-butyl-3-bethylimidazolium tetrafluoroborate ionic liquid 32

Cure monitoring and characterization of epoxy/amine networks...

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32nd Technical Conference of the American Society for Composites 2017

作者： Prozorovska, Liudmyla Muralidharan, Nitin Westover, Andrew Pint, Cary Adams, Douglas Department of Civil and Environmental Engineering Vanderbilt University NashvilleTN37235 United States Interdisciplinary Materials Science Program Vanderbilt University NashvilleTN37225 United States Department of Mechanical Engineering Vanderbilt University NashvilleTN37235 United States Material Science and Technology Division Oak Ridge National Laboratory Oak RidgeTN37831 United States

ISBN: (纸本)9781510853065

In the present work, electrochemical impedance spectroscopy (EIS) was employed for cure monitoring of bisphenol A/F based epoxy resin-polyoxypropylenediamine hardener systems modified with various concentrations of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) ionic liquid (IL). These systems exhibited phase separation induced by an increase in the molar mass through the curing of the resin. The progress of the curing process was accompanied by a steady increase of impedance for all types of samples, as expected, due to the increasing viscosity of the medium for increased degree of cure. The results were compared to those of unmodified resin-hardener systems. The sensitivity of EIS as a cure monitoring technique increased dramatically with the addition of the IL. The cure kinetics of the epoxy resin was characterized by differential scanning calorimetry and the data were used to create a model for comparison with the EIS results. The change of the ionic conductivity during curing as a function of IL concentration and the effect of IL loading on mechanical properties of the resin were also studied. We demonstrate that [BMIM]BF4 loading of 5wt.% increased the room temperature ionic conductivity of the fully cured product by an order of magnitude with only a 2.5% reduction in compression strength from that of pure epoxy. Copyright © (2017) by DEStech Publications, Inc. All rights reserved.

关键词： Epoxy resins

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