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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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Double-Cable Conjugated Polymers with Pendent Near-Infrared Electron Acceptors for Single-Component Organic Solar Cells

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Angewandte Chemie 2022年第35期134卷

作者： Shijie Liang Baiqiao Liu Dr. Safakath Karuthedath Jing Wang Dr. Yakun He Wen Liang Tan Hao Li Prof. Yunhua Xu Prof. Ning Li Prof. Jianhui Hou Prof. Zheng Tang Prof. Frédéric Laquai Prof. Christopher R. McNeill Prof. Christoph J. Brabec Prof. Weiwei Li Beijing Advanced Innovation Center for Soft Matter Science and Engineering & State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China Contribution: Data curation (lead) Formal analysis (lead) Investigation (equal) Writing - original draft (supporting) Writing - review & editing (supporting) Department of Chemistry School of Science Beijing Jiaotong University Beijing 100044 P. R. China KAUST Solar Center (KSC) Physical Sciences and Engineering Division (PSE) Material Science and Engineering Program (MSE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Kingdom of Saudi Arabia Contribution: Data curation (supporting) Formal analysis (supporting) Investigation (supporting) Writing - original draft (supporting) Writing - review & editing (supporting) Center for Advanced Low-dimension Materials College of Materials Science and Engineering Donghua University Shanghai 201620 P. R. China Contribution: Data curation (supporting) Formal analysis (supporting) Investigation (supporting) Methodology (supporting) Writing - review & editing (supporting) Institute of Materials for Electronics and Energy Technology (i-MEET) Friedrich-Alexander-Universität Erlangen-Nürnberg Martensstrasse 7 91058 Erlangen Germany Contribution: Data curation (supporting) Formal analysis (supporting) Investigation (supporting) Methodology (supporting) Writing - original draft (supporting) Writing - review & editing (supporting) Department of Materials Science and Engineering Monash University Wellington Road Clayton Victoria 3800 Australia State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China Contribution: Data curation (supporting) Formal analysis (supporting) Writing - review & editing (supporting) Contribution: Funding acquisition (supporting) Writing - review & editing (supportin

Double-cable conjugated polymers with near-infrared (NIR) electron acceptors are synthesized for use in single-component organic solar cells (SCOSCs). Through the development of a judicious synthetic pathway, the highly sensitive nature of the 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (IC)-based electron acceptors in basic and protonic solvents is overcome. In addition, an asymmetric design motif is adopted to optimize the packing of donor and acceptor segments, enhancing charge separation efficiency. As such, the new double-cable polymers are successfully applied in SCOSCs, providing an efficiency of over 10 % with a broad photo response from 300 to 850 nm and exhibiting excellent thermal/light stability. These results demonstrate the powerful design of NIR-acceptor-based double-cable polymers and will enable SCOSCs to enter a new stage.

关键词： Double-Cable Conjugated Polymers Electron Acceptors Near Infrared Single Component Solar Cells

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Effect of alkaline pre-treatment on the production characteristics of nanofibrillated cellulose from white ledger

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Palpu Chongi Gisul/Journal of Korea Technical Association of the Pulp and Paper Industry 2017年第5期49卷 86-96页

作者： Hwang, Lm Jeong Kim, Jin Mo Lee, Yong Kyu Won, Jong Myoung Program of Paper Science and Engineering Division of Forest Material Science and Engineering College of Forest and Environmental Sciences Kangwon National University Chuncheon24341 Korea Republic of

To evaluate the feasibility of NFC production using white ledger as a raw material, deinking and ash removal were carried out and fibrillation was performed with a grinder. In order to compare the fibrillation characteristics of white ledger, the fibrillation of HwBKP and SwBKP was performed in the same manner. Especially, white ledger is expected to be difficult to fibrillate by hornification phenomenon, so it is pretreated with 0.5, 1, 3 and 5% alkali solutions and then fibrillated. White ledger was found to be harder to fibrillate than HwBKP and SwBKP, and when pretreated with a low concentration alkali solution of up to 5%, fibrillation was remarkably improved. FTIR analysis showed no change in absorption band due to fibrillation and alkali pretreatment, and no apparent change in crystallinity and hydrogen bond index was observed. The CED polymerization degree of NFCs decreased with the progress of fibrillation, but the effect of alkali pretreatment was not clear. The average fiber length of NFC was decreased by fibrillation. In the case of HwBKP and SwBKP, the alkaline pretreatment effect on the average fiber length change was not clear. However, in the case of white ledger, the average fiber length was significantly decreased in the early stage of fibrillation and the difference from the untreated case was decreased as the fibrillation progressed. The relative specific energy consumptions in producing NFC at The relative specific energy consumptions in producing NFC at the same fibrillation level were 17.8 Wh/g for HwBKP, 25.1 Wh/g for SwBKP, and 37.4 Wh/g for white ledger, respectively. The specific energy consumption of the white ledger was reduced to 18.1 Wh/g when it is pretreated with 3-5% alkali solution.

关键词： Cellulose

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Effect of the surface treatment with CNF/oxidized starch on the physical properties and the printability of paper

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Palpu Chongi Gisul/Journal of Korea Technical Association of the Pulp and Paper Industry 2017年第6期49卷 102-110页

作者： Hwang, Im Jeong Lee, Yong Kyu Won, Jong Myoung Program of Paper Science and Engineering Division of Forest Material Science and Engineering College of Forest and Environmental Sciences Kangwon National University Chuncheon24341 Korea Republic of

This study was carried out to investigate the effect of the surface treatment with CNF alone and/or CNF-oxidized starch mixtures on the physical properties and printability of paper. CNF has better fluidity than the oxidized starch during coating process, and its coverage was excellent even though the small amount was applied to paper surface. The surface roughness was somewhat reduced by the formation of thin film. The bulk of the paper showed no significant change when applied in small amounts of CNF and/or oxidized starch mixtures, but decreased as the application amount exceeded 5 g/m2. The air resistance of paper was 853 seconds when it was applied with CNF only 2.35 g/m2, and it was impossible to measure the air permeability regardless of the application amount when the mixtures of oxidized starch were applied on the paper surface. The tensile strength, tear strength, bending strength and folding endurance, as well as elongation, were improved by surface treatment with CNF and/or the mixtures of CNF and oxidized starch. The dry pick strength of the surface treated paper showed the lowest value in the CNF treatment, and it was improved with the increase of oxidized starch content. The wet pick strength was poor enough to be unmeasurable until CNF was applied by 2 times, and excellent results were obtained as the amount of oxidized starch added increased.

关键词： Tensile strength

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Effect of PCC pretreatment with PAM on the paper properties

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Palpu Chongi Gisul/Journal of Korea Technical Association of the Pulp and Paper Industry 2017年第4期49卷 65-73页

作者： Won, Jong Myoung Cho, Byoung-Uk Lee, Yong-Kyu Program of Paper Science and Engineering Division of Forest Material Science and Engineering College of Forest and Environmental Sciences Kangwon National University Chuncheon24341 Korea Republic of

The study on the pretreatment of PCC with PAM (Polyacrylamide) was carried out as a part of solving the problem of decreasing the paper strength due to the increase of the filler usage. Anionic PAM was used for pretreatment of PCC, and the average particle size and specific surface area of PCC were measured by PAM dosage. A combination of anionic and cationic PAM was also applied to observe PCC particle size changes. Filler loading experiments were carried out using pretreated PCCs under selected conditions and the changes in paper properties were investigated. The PCC average particle size increased to 103.5 um as the anionic PAM dosage increased to 0.1%, then decreased, and the specific surface area of PCC showed the opposite. When using anionic and cationic PAM combinations, the average particle size of PCC was determined by the amount of anionic PAM. When PCC pretreated with 0.1% anionic PAM was used as a filler, the bulk, tensile index and burst index increased 3.3%, 4.89%, and 24.2%, respectively, while the ash content was increased by about 5%. Therefore, it is expected that PCC pretreatment using anionic PAM can be used as a useful means for improving paper properties.

关键词： Particle size

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Metallo-Helicoid with Double Rims: Polymerization Followed by Folding by Intramolecular Coordination

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Angewandte Chemie 2020年第3期133卷

作者： Dr. Guang-Qiang Yin Sneha Kandapal Chung-Hao Liu Dr. Heng Wang Dr. Jianxiang Huang Shu-Ting Jiang Tan Ji Yu Yan Sandra Khalife Dr. Ruhong Zhou Dr. Libin Ye Dr. Bingqian Xu Dr. Hai-Bo Yang Dr. Mu-Ping Nieh Dr. Xiaopeng Li College of Chemistry and Environmental Engineering Shenzhen University Shenzhen Guangdong 518055 China Single Molecule Study Laboratory College of Engineering and Nanoscale Science and Engineering Center University of Georgia Athens GA 30602 USA Department of Chemical and Biomolecular Engineering University of Connecticut Storrs CT 06269 USA Institute of Quantitative Biology Zhejiang University Hangzhou Zhejiang 310027 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China Department of Chemistry University of South Florida Tampa FL 33620 USA Department of Cell Biology Microbiology and Molecular Biology University of South Florida Tampa FL 33620 USA Polymer Program Institute of Material Science University of Connecticut Storrs CT 06269 USA

In this study, we established a feasible strategy to construct a new type of metallo-polymer with helicoidal structure through the combination of covalent polymerization and intramolecular coordination-driven self-assembly. In the design, a tetratopic monomer ( M ) was prepared with two terminal alkynes in the outer rim for polymerization, and two terpyridines (TPYs) in the inner rim for subsequent folding by selective intramolecular coordination. Then, the linear covalent polymer ( P ) was synthesized by polymerization of M via Glaser-Hay homocoupling reaction. Finally, intramolecular coordination interactions between TPYs and Zn(II) folded the backbone of P into a right- or left-handed metallo-helicoid ( H ) with double rims. Owing to multiple positive charges on the inner rim of helicoid, double-stranded DNA molecules (dsDNA) could interact with H through electrostatic interactions. Remarkably, dsDNA allowed exclusive formation of H with right handedness by means of chiral induction.

关键词： coordination-driven self-assembly helicoid metallo-polymers terpyridine tetraphenylethylene

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

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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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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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Anisotropic superconductivity and frozen electronic states at the (111) LaAlO3/SrTiO3 interface

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Physical Review B 2018年第2期98卷 024504-024504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 Physics National University of Singapore 117542 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

We report measurements of the superconducting properties of the two-dimensional (2D) gas that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) in the (111) crystal orientation, a system that permits in situ tuning of carrier density and disorder by means of a back-gate voltage Vg. Like the (001) oriented LAO/STO interface, superconductivity at the (111) LAO/STO interface can be tuned by Vg. The 2D superconductivity in these (111) LAO/STO samples shows an in-plane anisotropy, being different along different interface crystal directions, and “remembers” the disorder landscape at which they are cooled through the superconducting transition. The low energy scale and other characteristics of this memory effect distinguish it from charge-trapping effects previously observed in (001) interface samples.

关键词： Electrical conductivity Impurities in superconductors Superconducting phase transition Superconductivity Interfaces Solid-solid interfaces Superconductors Two-dimensional electron gas Type-II superconductors Hall bar Resistivity measurements

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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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