检索结果-南通市图书馆

Switchable carbamate coagulants to improve recycling ionic liquid from biomass solutions

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Green Chemical Engineering 2021年第4期2卷 384-391页

作者： Julia L.Shamshina Ying Qin Ken Belmore daniel T.daly Robin d.Rogers Fiber and Biopolymer Research Institute Department of Plant and Soil ScienceTexas Tech UniversityLubbockTX79409USA Alabama Institute for Manufacturing Excellence The University of AlabamaTuscaloosaAL35487USA department of Chemistry and Biochemistry The University of AlabamaTuscaloosaAL35487USA College of Arts&Sciences The University of AlabamaTuscaloosaAL35487USA Solutions Inc.P.O.Box 2206TuscaloosaAL35403USA

A reversible amine-carbamate approach has been developed to reduce the use of antisolvents such as water in the coagulation of biopolymers from ionic liquid(IL)solution and thus improve the economy of IL *** and chitin were recovered from 1-ethyl-3-methylimidazolium acetate([C_(2)mim][OAc])solution by introducing the miscible amines triethanolamine(TEA),ethylenediamine(EdA),or butylamine(BA)and bubbling CO_(2) at 40℃ and atmospheric pressure through the solutions to form carbamate salts in situ which resulted in biopolymer *** gave the best results because of its low boiling point and low viscosity,which benefited both biopolymer recovery and IL *** films and fibers could be formed by extrusion of an MCC/[C_(2)mim]-[OAc]solution into a coagulating bath comprised of a 1:1 M mixture of[C_(2)mim][OAc]and butylammonium butylcarbamate(BA-carbamate).The cellulose,IL,amine,and CO_(2) were easily separated,although the cellulose recovered required some water washings to remove traces of *** to 96.4%of the[C_(2)mim][OAc]could be recovered,76.2%from the coagulation bath and 20.2%from the water *** recycled IL was suitable for another cycle of cellulose dissolution and extrusion and 84.6%of the IL used for the second cycle was *** further work is needed,not the least of which will be reducing the amount of water needed for washing steps,some promising features of this process point the way for new directions for more economically viable IL recycling processes in biomass treatment with ILs.

关键词： Carbamate Ionic liquid Recovery Switchable Coagulation Biopolymers Carbamates IL recycle

Enhancing heat transfer at the micro-scale using elastic turbulence

在线全文

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2015年第3期5卷 103-106页

作者： R.d.Whalley W.M.Abed d.J.C.dennis R.J.Poole School of Engineering University of Liverpool LMFA Universite de LyonEcole Centrale de Lyon

Small concentrations of a high-molecular-weight polymer have been used to create so-called ＂elastic tur- bulence＂ in a micro-scale serpentine channel geometry. It is known that the interaction of large elastic stresses created by the shearing motion within the fluid flow with streamline curvature of the serpentine geometry leads initially to a purely-elastic instability and then the generation of elastic turbulence. We show that this elastic turbulence enhances the heat transfer at the micro-scale in this geometry by up to 300% under creeping flow conditions in comparison to that achieved by the equivalent Newtonian fluid flow.

关键词： Elastic turbulence Viscoelasticity Serpentine channel Micro-mixing Heat transfer

Male competition and speciation： expanding our framework for speciation by sexual selection

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2018年第1期64卷 69-73页

作者： Alycia C. R. LACKEY Michael d. MARTIN Robin M. TINGHITELLA department of Biological Sciences Binghamton University Binghamton NY 13902 USA department of Biology Oxford College of Emory University Oxford GA 30054 USA department of Biological Sciences University of Denver Denver CO 80208 USA

IntroductionSexual selection is a powerful source of rapid evolutionary change, and there is a long-standing hypothesis that it can cause reproductive isolation. However, our understanding of speciation by sexual selection is largely limited to mechanisms by which sexual selection via female mate choice can drive divergence （i.e., when male mating signals and female preferences for those signals diversify; Panhuis et al. 2001; Maan and Seehausen 2011）. Male competition for mates--darwin＇s second mechanism of sexual selection-can also favor rapid and dramatic phenotypic and genotypic changes, yet it has been all but overlooked in speciation research （darwin 1859, 1871; Seehausen and Schluter 2004;

关键词：竞争框架配偶选择多样化达尔文机制信号进化

Nonlinear optics on silicon-rich nitride--a high nonlinear figure of merit CMOS platform[Invited]

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2018年第5期6卷 I0075-I0091页

作者： d.T.H.TAN K.J.A.OoI d.K.T.NG Photonics devices and Systems Group Singapore University of Technology and Design8 Somapah Rd.Singapore 487372Singapore data Storage Institute Agency for ScienceTechnology and Research(A*STAR)2 Fusionopolis Way#08-01 InnovisSingapore 138634Singapore

CMOS platforms with a high nonlinear figure of merit are highly sought after for high photonic quantum efficiencies, enabling functionalities not possible from purely linear effects and ease of integration with CMOS electronics. Silicon-based platforms have been prolific amongst the suite of advanced nonlinear optical signal processes demonstrated to date. These include crystalline silicon, amorphous silicon, Hydex glass, and stoichio- metric silicon nitride. Residing between stoichiometric silicon nitride and amorphous silicon in composition, silicon-rich nitride films of various formulations have emerged recently as promising nonlinear platforms for high nonlinear figure of merit nonlinear optics. Silicon-rich nitride films are compositionally engineered to create bandgaps that are sufficiently large to eliminate two-photon absorption at telecommunications wavelengths while enabling much larger nonlinear waveguide parameters （5x-500x） than those in stoichiometric silicon uitride. This paper reviews recent developments in the field of nonlinear optics using silicon-rich nitride platforms, as well as the outlook and future opportunities in this burgeoning field.

关键词： Nonlinear optics silicon-rich nitride a high Nonlinear figure of merit CMOS platform

Sol-Gel Preparation of Graphite/TiO_2 Composite Particles and Their Electrorheological Effect

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2005年第1期21卷 83-86页

作者： Ling ZHENG and Yinong LIState Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, ChinaAssoc. Prof., Ph.d., Lab. of Mech. Transmission Chongqing Univ. Chongqing 400044 China

Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRd, SEM and TG-dTA. The electrorheological properties of the ER fluid containing the particles were measured by a Couette-type rheometer under shear rates of 1-136 s-1 and AC electric fields of 0-3 kV/mm. The experimental results show that the leaking current density of the ER fluid is higher than that of pure titanium dioxide particles dispersed in damping oil. The shear yield stress of the ER fluid increases with increasing electric field and exhibits a typical Bingham flow behavior. The suspension demonstrates an excellent ER performance (τ/τo=1200) compared with conventional ER fluids (τ/τ0 ≤500). The sedimentation of the ER fluid is improved obviously due to the coating effect of the particles.

关键词： Electrorheological fluid Composite particle Graphite TiO2 Sol-gel

Bifid pancreatic tail as cause of acute pancreatitis

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic diseases International 2018年第5期17卷 480-481页

作者： Hanna Rafaela Ferreira dalla Pria Rafael Andrade Santiago Fernanda Garozzo Velloni Giuseppe d’ippolito department of Imaging Universidade Federal de Sao PauloSao PauloBrazil diagnos ticos da Ametica S.A.dASA. Sao PauloBrazil Grupo Fleury Sao PauloBrazil

To the Editor:Wepresentacaseofa22-year-oldwomanwithrecurrent episodes of acute pancreatitis. The patient had no known risk factors such as history of alcoholism, smoking, pre-existing medical conditions, family member... 详细信息

关键词： pre-existing medicall dilatation or cholelithiasis

Magnetic properties, magnetoresistivity and magnetocaloric effect in Gd_xLa_(1-x)-MnSi alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2009年第4期27卷 684-687页

作者： T.I.Ivanova S.A.Nikitin W.Suski G.A.Tskhadadze I.A.Ovtchenkova d.Badurski Physics department Moscow State University 119992 Moscow Russia International Laboratory of High Magnetic Fields and Low Temperatures Wroclaw Poland Polish Academy of Sciences Trzebiatowski Institute of Low Temperatures and Structure Research P.O.Box 1410 50-950 Wroclaw 2 Poland

The results of magnetization, magnetoresistivity and magnetocalofic effect （MCE） studies performed on polycrystalline samples of the GdxLa1-xMnSi （x=0.5, 0.6, 0.7, 0.8, 0.9, 1.0） compounds were presented. Complex measurements were carried out on the GdxLa1-xMnSi compounds to determine the influence of substitution in the rare earth （R） sublattice on the magnetic and related properties of these compounds. The compounds with x≤0.6 demonstrated two magnetic phase transitions （ferromagnetic to paramagnetic and antiferro- magnetic to ferromagnetic） both of which were first order. Anomalies in the magnetocaloric effect, electroresistivity and magnetoresistivity were observed in the temperature ranges of the magnetic phase transitions. The temperature dependences of MCE and magnetoresistivity for these compounds correlated with the temperature dependence of magnetization.

关键词： magnetocaloric effect magnetoresistivity magnetic phase Iransition itinerant magnetism rare earths

Room Temperature Ferromagnetism in dual doped (Mn^(2+), Ni^(2+)) ZnO Codoped with Li^(1+) Prepared Using EdTA Sintered at Low Temperature

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第3期30卷 275-279页

作者： R.Pugaze A.Sivagamasundari d.Vanidha S.Chandrasekar A.Arunkumar S.Rajagopan R.Kannan department of Physics Pondicherry Engineering College department of Chemistry Pondicherry Engineering College

Nanopowders of Znl_x_y_zMnxNiyLizO [（x = 0.04, y = 0, z = 0）, （x = 0.04, y = 0.03, z = 0） and （x = 0.04, y = 0.03, z = 0.03）] have been synthesized by sol-gel precursor route using ethylene diamine tetraacetic acid （EdTA） as a metal chelating agent. X-ray diffraction analysis confirms the formation of wurtzite hexagonal structure for all the three compositions. Mn2＋ doped ZnO exhibits room temperature ferromagnetism （RTFM）, and it is found that further Ni2＋ doping has decreased Ms because of limit of solid solubility of transition metal in ZnO. But codoping of monovalent Li1＋, further increases the ferromagnetism （FM） value, due to introduction of free carriers compared to the dual doped samples. Photoluminescence （PL） spectra of the system, exhibit near band edge （NBE） emission peak at --464 nm due to the electron transition from interstitials to the valence band. Recombination of conduction electron with hole trapped at oxygen vacancy, leads to prominent defect emission peaks at --482 nm and 532 nm. The evidence of the formation of metaI-EdTA complexes are found from the Fourier transform infrared spectra at 2800-3800 cm-1 with shifting, splitting of the peak and also drastic variations in the intensity.

关键词： Mn-doped dual doped Li codoped Ferromagnetism Photoluminescence Fourier transform infrared (FTIR) spectroscopy

Recent trends on wound management:New therapeutic choices based on polymeric carriers

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Pharmaceutical Sciences 2020年第6期15卷 661-684页

作者： Mehmet Evren Okur Ioannis d.Karantas Zeynep Senyigit Neslihan Ustundag Okur Panoraia I.Siafaka department of Pharmacology Faculty of PharmacyUniversity of Health SciencesIstanbul TR-34668Turkey Hippokration General Hospital 2nd Clinic of Internal MedicineThessaloniki 54124Greece department of Pharmaceutical Technology Faculty of PharmacyIzmir Katip Qelebi UniversityIzmirTurkey department of Pharmaceutical Technology Faculty of PharmacyUniversity of Health SciencesIstanbul TR-34668Turkey department of Chemistry Aristotle University of ThessalonikiThessaloniki 54124Greece

Wound healing is an unmet therapeutic challenge among medical society since wound assessment and management is a complex procedure including several factors playing major role in healing *** can mainly be categorized as acute or *** is well referred that the acute wound displays normal wound physiology while healing,in most cases,is seemed to progress through the normal phases of wound *** the other hand,a chronic wound is physiologically *** main problem in wound management is that the majority of wounds are colonized with microbes,whereas this does not mean that all wounds will be *** this review,we address the problems that clinicians face to manage while treat acute and chronic ***,we demonstrate the pathophysiology,etiology,prognosis and microbiology of *** further introduce the state of art in pharmaceutical technology field as part of wound management aiming to assist health professionals to overcome the current implications on wound *** addition,authors review researches which included the use of gels and dermal films as wound healing *** can be said that natural and synthetic drugs or carriers provide promising solutions in order to meet the wound management ***,are the current strategies as desirable as medical society wish?

关键词： Wound Infection dressings Scaffolds Biomaterials Wound healing