162,249 research outputs found
INNOVATIVE PILLAR[6]ARENE-BASED STATIONARY PHASES FOR HIGH-RESOLUTION GAS CHROMATOGRAPHIC ANALYSES
No full textIn this work, the synthesis, fabrication, and characterization of new stationary phases based on pillar[6]arene derivative modified by long alkyl chains (P6A-C10) for high-resolution gas chromatographic (GC) analyses are reported. Pillar[n]arenes are a new class of macrocyclic hosts that can accommodate specific guests due to their highly symmetrical and rigid pillar architectures with π-electron rich cavities. Quantum chemistry calculations have been performed, showing a difference in non-covalent interactions with the P6A-C10 pillar framework, which leads to specific selectivity for aromatic compounds. The GC columns prepared with these innovative stationary phases exhibited a medium polarity, and good reproducibility for run-to-run, day-to-day, and column-to-column analyses [1], demonstrating great potential as new stationary phases in separation science. Furthermore, peculiar advantages are achieved if compared with the commercial HP-5, HP-35, DB-17, and PEG-20M columns, showing unmatched resolving capabilities toward chloroaniline, bromoaniline, iodoaniline, toluidine, and xylene isomers [2].
References:
1. Sun, T., Chen, R., Huang, Q., Ba, M., Cai, Z., Hu, S., Liu, X., Nardiello, D., & Quinto, M., ACS Appl. Mater. Interfaces 14 (2022) 56132−56142.
2. Sun, T., Chen, R., Huang, Q., Ba, M., Cai, Z., Chen, H., Qi, Y., Chen, H., Liu, X., Nardiello, D., & Quinto, M., Anal. Chim. Acta 1251 (2023) 340979
Remarks on time dependent periodic Navier-Stokes flows on a two-dimensional torus
No full textThis note is a continuation of the earlier paper [Chen, Z. M., Price, W. G.: Time dependent periodic Navier–Stokes flows on a two-dimensional torus. Commun. Math. Phys. {\bf 179}, 577–597 (1996)], where the evidences of the occurrence for the time dependent periodic Navier–Stokes flows were found based on a combination of analysis and computation. This investigation is now confirmed via rigorous analysis. The existence of the time dependent periodic Navier–Stokes flows on a two-dimensional torus is prove
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
Full text linkFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
ISOMER SEPARATIONS BY INNOVATIVE GAS CHROMATOGRAPHY STATIONARY PHASES
No full textThe chromatographic separation of aromatic amines and xylenes isomers represents a big issue in chemical and petroleum industries, owing to their high similarity in terms of molecular sizes, polarity, and boiling points: as a result, commercial columns very often do not allow their complete peak separation. For this reason, several typologies of materials with different structures and properties have been developed and proposed as gas chromatography stationary phases in recent years. Macrocycles and ionic liquid-based chain-typed copolymers have emerged, due to their special chromatographic selectivity and separation mechanisms, resulting from their three-dimensional structures and outstanding thermal stability. Very recently, innovative stationary phases based on functionalized calixarene-polyethylene glycol (C4A-mPEG) [1], and amphiphilic triblock copolymer bonded with benzimidazolium ionic liquid (TCP-Bim) [2] were designed, characterized, and used for GC separations of aromatic isomers. The separation features of the C4A-mPEG stationary phase, resulting from multiple molecular recognition processes with analytes, including π-π, H-bonding, dipole-dipole, and van der Waals interactions, allowed to obtain high-resolution performances for a wide range of compounds and their isomers, especially benzaldehydes, phenols, and anilines. Moreover, compared with 4-tertbutyl calix[4]arene (C4A) and polyethylene glycol (PEG) stationary phases, a higher resolving capability was also observed for the separation of toluidine and xylidine isomers. The separation capabilities of the TCP-Bim columns are attributable to different analyte-stationary phase interaction mechanisms, arising from the particular TCP-Bim structure that combines ionic liquid and copolymer peculiarities, showing stronger retention towards aromatic compounds. The high-resolution capabilities of the TCP-Bim column were also tested with different aliphatic cis-/trans-isomers; the excellent separation performances for analytes with very similar properties demonstrated the good potential of these innovative materials as new classes of stationary phases for high-resolution GC separations.
References:
1. Chen, R., Cai, Z., Li, W., Huang, Q., Nardiello, D., Quinto, M., Liu, X., Hu, S., & Sun, T., Chem. Biodiversity 19 (2022) e202200829.
2. Huang, Q., Cai, Z., Chen, R., Zhang, W., Nardiello, D., Quinto, M., Liu, X., Hu, S., & Sun, T., Microchemical Journal 183 (2022) 108084
Faust : Romance Of The Secret Tribunals / By George W. M. Reynolds, Author Of "The Mysteries Of London", "Pickwick Abroad", &c. Illustrated In The First Style Of The Art
No full textFAUST : ROMANCE OF THE SECRET TRIBUNALS / BY GEORGE W. M. REYNOLDS, AUTHOR OF "THE MYSTERIES OF LONDON", "PICKWICK ABROAD", &C. ILLUSTRATED IN THE FIRST STYLE OF THE ART
Faust : Romance Of The Secret Tribunals / By George W. M. Reynolds, Author Of "The Mysteries Of London", "Pickwick Abroad", &c. Illustrated In The First Style Of The Art (1)
Cover (1)
Umschlagtitel (8)
Titelseite (9)
Contents (10)
Illustrations / Prologue (11)
Prologue (12)
Chapter I.-XCV. (14)
Epilogue (119
Effect of postgrowth hydrogen treatment on defects in GaNP
Full text linkEffect of postgrowth hydrogen treatment on defects and their role in carrier recombination in GaNP alloys is examined by photoluminescence (PL) and optically detected magnetic resonance. We present direct experimental evidence for effective activation of several defects by low-energy subthreshold hydrogen treatment (andlt;= 100 eV H ions). Among them, two defect complexes are identified to contain a Ga interstitial. Possible mechanisms for the H-induced defect activation and creation are discussed. Carrier recombination via these defects is shown to efficiently compete with the near band-edge PL, explaining the observed degraded optical quality of the alloys after the H treatment.Original Publication:Daniel Dagnelund, Xingjun Wang, C W Tu, A Polimeni, M Capizzi, Weimin Chen and Irina Buyanova, Effect of postgrowth hydrogen treatment on defects in GaNP, 2011, APPLIED PHYSICS LETTERS, (98), 14, 141920.http://dx.doi.org/10.1063/1.3576920Copyright: American Institute of Physicshttp://www.aip.org
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
Lyophyllum pallidofumosum Y. H. Ma, W. M. Chen & Y. C. Zhao 2022, sp. nov.
No full textLyophyllum pallidofumosum Y. H. Ma, W. M. Chen & Y. C. Zhao sp. nov. (Figs. 1A, 3) MycoBank: MB 844903 Etymology: — pallidofumosum, refers to the morphological similarity of the new species to L. fumosum. Diagnosis:— Lyophyllum pallidofumosum differs from the other species of the L. decastes complex by a greyish orange pileus surface, margin with waves when old; globose to subglobose basidiospores (4.5–5.6 × 4.3–5.4 µm), clavate basidia (25–34 × 7–9 µm); occurring in a mixed forest dominated by Pinus yunnanensis, Pinus armandi, and Quercus fabrei; and the highest growth rate on the YPD medium,. Holotype:— CHINA, Yunnan Province, Xuanwei City, Reshui Town, in a mixed forest, 25°58′17″ N, 103°44′50″ E, elev. 2344m, 09 September 2021, Yuanhao Ma, Weimin Chen, Ping Liu, 21rs0242 (HKAS 124190) Description:—pileus 20–60 mm in diam., Pileus shape convex and margin involute when young, applanate, margin waves when old. Pileus colour slightly desaturated orange (5B3–5), greyish orange (6B5), oak brown (5D5–6). Lamellae adnate or subdecurrent. Lamellae colour white (5A1) to light greyish orange (5B2). Context white to whitish. Stipe cylindrical slightly enlarged towards base, central, solid, tough in texture, 30–80 × 8–15 mm. Stipe colour white (5A1) to light greyish orange (5B2). Basidiospores hyaline, globose to subglobose, smooth, with a single large oil-drop and a small apiculus, (4.26–) 4.55–5.54 (–5.76) × (4.15–) 4.30–5.36 (–5.57) µm, (m/n/p=113/6/2, l m =5.06 ± 0.31µm, w m =4.83 ±0.31µm), Q= (1.00–) 1.01–1.11 (–1.12), Q m =1.05 ±0.32. Basidia 4-spored, clavate, sometimes ventricose, (24.10–) 25.53–33.50 (–35.36) × (6.78–) 7.09–8.78 (–9.63) µm, l m =29.08 ± 2.31µm, w m =7.89 ±0.55µm, Q= (2.93–) 3.15–4.24 (–4.44), Q m =3.70 ±0.34; sterigmata 1.77–3.87 µm long. Some with clamp connections. Lamellae without cheilocystidia and pleurocystidia. Colonies 43–45 mm radius after 24 d at 22℃ in the dark on YPD, white, downy to cottony with loose aerial hyphae; some with clamp connections. Habitat:—solitary, gregarious or cespitose on the ground as saprobic in a mixed forest dominated by Pinus yunnanensis, Pinus armandi, and Quercus fabrei. Additional specimens examined:— CHINA, Yunnan Province, Xuanwei City, Reshui Town, in a mixed forest, 25°58′17″ N, 103°44′50″ E, elev. 2344m, 24 July 2019, YAASM6138 (HKAS 124189, Paratype); ibid., Shangri-La County, 16 October 2020, YAASM6215; ibid., 26 July 2006, yang 4742 (HKAS 50539); ibid., Lanping County, Jinding Town, 15 October 2011, zhao 1334 (HKAS 74287). Ex-type: YAASM6628 and YAASM6629, isolated from the inner tissues of two basidiomata. Ex-type sequences:— YAASM6628/HKAS124190a = LSU: ON834576, ITS: ON680829; YAASM6629/ HKAS124190b = LSU: ON834577, ITS: ON680830.Published as part of Ma, Yuanhao, Liu, Ping, Zhao, Ziyue, Chen, Weimin & Zhao, Yongchang, 2022, Lyophyllum pallidofumosum sp. nov. (Lyophyllaceae, Agaricales), from southwestern China, pp. 173-183 in Phytotaxa 576 (2) on page 178, DOI: 10.11646/phytotaxa.576.2.3, http://zenodo.org/record/746126
Perspektywy rozwoju biotechnologii w Polsce
Full text linkWażnym czynnikiem rozwoju biotechnologii w Polsce są nowoczesne badania naukowe. Artykuł Perspektywy rozwoju biotechnologii w Polsce zwraca uwagę na to, że wiedza z zakresu nauk biologicznych i medycznych przyczynia się do większej konkurencyjności zarówno ośrodków naukowych i badawczych, jak i przedsiębiorstw. Biotechnologiczne projekty naukowo–badawcze realizowane w Polsce nie tworzą jeszcze podstaw do wytwarzania produktów biotechnologicznych w takim zakresie, by polskie przedsiębiorstwa mogły konkurować na rynku międzynarodowych. Jedną z przyczyn, którą analizuje Autor w artykule, jest niewystarczające inwestowanie w rozwój nauki i wsparcie dla małych i średnich firm w sektorze biotechnologii. MSP są najważniejszym elementem rozwoju tego sektora, ponieważ koncentrują się na tworzeniu i rozwoju nowoczesnych produktów biotechnologicznych. Artykuł został podzielony na dwie części: Szanse rozwoju nowoczesnej gospodarki w Polsce bez biotechnologii oraz Edukacja i projekty B+R. Autor finalizuje rozważania, pokazując pozytywny scenariusz dla rozwoju sektora biotechnologicznego w Polsce.Biotechnology uses biological processes in the development of technology or manufacture of a product. It is forecasted that Polish biotechnology industry will exceed very quickly. The technology and science parks in Poland have invested millions Euros to build new laboratories. Polish market is fuelled by increased R&D funding, central and regional governments initiatives. The article on “Polish perspectives of biotechnology development” identifies significant factors for biotechnology project development. It also indicates the examples of government biotechnology initiatives in the world. The author focuses on the statistical analysis of the research and development projects conducted by Polish scientist in scientific laboratories. His main conclusion is that biotechnology will be very important in developing Poland, Polish universities, research and development organizations.Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00
Sebastes ensifer Chen 1971
No full textSebastes ensifer Chen, 1971. Swordspine Rockfish. To 30.5 cm (12 in) TL (Miller and Lea 1972). Oregon (43°56’N) (NWFSC-FRAM) to Banco Ranger (28°25’N, 115°32’W), central Baja California (Chen 1971). Benthic; depth: 50–433 m (164–1,420 ft) (min.: M.L., unpubl. data; max.: Miller and Lea 1972).Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 108, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/557800
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