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211.
Jer-Shien Chen San-Liang Lee Hong-Chang Kung Hen-Wai Tsao 《Optical and Quantum Electronics》2009,41(11-13):859-871
We propose a numerical model, including modulation transform function and self-sustained pulsation condition, to estimate the self-sustained pulsation frequency, matched to the measured pulsation frequency, which considers the structure factors in a two-section distributed feedback laser with a thin shift-layer. 相似文献
212.
Uniformly spaced semielliptical notches in rectangular beams under pure bending are examined photoelastically. Minimum stress-concentration factors, produced by multiple elliptical notching of beams, are obtained for wide ranges of notch width, semiminor elliptical axis, notch depth, notch pitch and depth of beam. In particular, the geometries of the optimum elliptical notch producing the least stress concentration are obtained for a practical range of parameters. Stress-concentration factors for beams with multiple semi-elliptical notches are compared to those for beams with single semielliptical notches and to those for beams with semicircular notches. The maximum reduction of stress-concentration factor for beams with multiple semielliptical notches is to approximately 37 percent of the stress-concentration factor for beams with single semielliptical notches. Within the range of parameters investigated, the stress-concentration factor for beams with multiple semielliptical notches was 15 to 37 percent less than that for multiple semicircular notches. 相似文献
213.
Ching Ting Tsao Meng Hsuan Hsiao Mengying Y. Zhang Sheeny Lan Levengood Miqin Zhang 《Macromolecular rapid communications》2015,36(3):332-338
Smart hydrogels play an increasingly important role in biomedical applications, since materials that are both biocompatible and multi‐stimuli‐responsive are highly desirable. A simple, organic solvent‐free method is presented to synthesize a biocompatible hydrogel that undergoes a sol–gel transition in response to multiple stimuli. Methoxy‐poly(ethylene glycol) (mPEG) is modified into carboxylic‐acid‐terminated‐methoxy‐poly(ethylene glycol) (mPEG‐acid), which is then grafted onto chitosan via amide linkages yielding mPEG‐g‐chitosan. Grafting of mPEG onto hydrophobic chitosan imparts hydrophilic properties to the resultant polymer. The mPEG‐g‐chitosan gel exhibits a controllable multi‐stimuli‐responsive property. The balance between hydrophilicity and hydrophobicity is believed to confer mPEG‐g‐chitosan with stimuli‐responsive behavior. The effect of salt concentration, solute concentration, temperature, and pH on the sol–gel transition of mPEG‐g‐chitosan is evaluated and the underlying mechanisms of mPEG‐g‐chitosan polymer packing and gelation property is discussed.
214.
Hans-Georg Steinrück Chuntian Cao Maria R. Lukatskaya Christopher J. Takacs Gang Wan David G. Mackanic Yuchi Tsao Jingbo Zhao Brett A. Helms Kang Xu Oleg Borodin James F. Wishart Michael F. Toney 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(51):23380-23387
Super-concentrated “water-in-salt” electrolytes recently spurred resurgent interest for high energy density aqueous lithium-ion batteries. Thermodynamic stabilization at high concentrations and kinetic barriers towards interfacial water electrolysis significantly expand the electrochemical stability window, facilitating high voltage aqueous cells. Herein we investigated LiTFSI/H2O electrolyte interfacial decomposition pathways in the “water-in-salt” and “salt-in-water” regimes using synchrotron X-rays, which produce electrons at the solid/electrolyte interface to mimic reductive environments, and simultaneously probe the structure of surface films using X-ray diffraction. We observed the surface-reduction of TFSI− at super-concentration, leading to lithium fluoride interphase formation, while precipitation of the lithium hydroxide was not observed. The mechanism behind this photoelectron-induced reduction was revealed to be concentration-dependent interfacial chemistry that only occurs among closely contact ion-pairs, which constitutes the rationale behind the “water-in-salt” concept. 相似文献
215.
Yingche Chen Christopher M. Clouthier Kelvin Tsao Miroslava Strmiskova Hugo Lachance Prof. Jeffrey W. Keillor 《Angewandte Chemie (International ed. in English)》2014,53(50):13785-13788
A fluorescent protein‐labeling strategy was developed in which a protein of interest (POI) is genetically tagged with a short peptide sequence presenting two Cys residues that can selectively react with synthetic fluorogenic reagents. These fluorogens comprise a fluorophore and two maleimide groups that quench fluorescence until they both undergo thiol addition during the labeling reaction. Novel fluorogens were prepared and kinetically characterized to demonstrate the importance of a methoxy substituent on the maleimide in suppressing reactivity with glutathione, an intracellular thiol, while maintaining reactivity with the dithiol tag. This system allows the rapid and specific labeling of intracellular POIs. 相似文献
216.
Xi Yin Steven A. Warren Yung‐Tin Pan Kai‐Chieh Tsao Dr. Danielle L. Gray Dr. Jeffery Bertke Prof.Dr. Hong Yang 《Angewandte Chemie (International ed. in English)》2014,53(51):14087-14091
A new motif for infinite metal atom wires with tunable compositions and properties is developed based on the connection between metal paddlewheel and square planar complex moieties. Two infinite Pd chain compounds, [Pd4(CO)4(OAc)4Pd(acac)2] 1 and [Pd4(CO)4(TFA)4Pd(acac)2] 2 , and an infinite Pd? Pt heterometallic chain compound, [Pd4(CO)4(OAc)4Pt(acac)2] 3 , are identified by single‐crystal X‐ray diffraction analysis. In these new structures, the paddlewheel moiety is a Pd four‐membered ring coordinated by bridging carboxylic ligands and μ2 carbonyl ligands. The planar moiety is either Pd(acac)2 or Pt(acac)2 (acac=acetylacetonate). These moieties are connected by metallophilic interactions. The results showed that these one‐dimensional metal wire compounds have photoluminescent properties that are tunable by changing ligands and metal ions. 3 can also serve as a single source precursor for making Pd4Pt bimetallic nanostructures with precise control of metal composition. 相似文献
217.
The post-data performances of normal tolerance intervals are studied. Under a robust Bayesian predictive scheme, we establish
the ordering and bounds of the confidence estimators. It is found that the nominal confidence coefficient tends to be extreme
yet coincides with the limiting Bayes estimators in some scenarios. A remark on the choice of beta priors is also given. 相似文献
218.
Chuan-Chung Chang Ludovic Angot Hsiao-Yue Tsao Chir-Weei Chang Cheng-Chung Lee 《Optical Review》2009,16(2):126-128
Point spread functions at different field angles and phase deviations of the cubic mask are used for image restoration to
analyze the off-axis performance of a wavefront coded imaging system. 相似文献
219.
Liu Dehua Huamg Shian Li Ming Sun Yan Liu Tianzhong Ouyang Fan Tsao George T. 《Applied biochemistry and biotechnology》1996,57(1):593-598
Applied Biochemistry and Biotechnology - Two different strains of baker’s yeast are cultivated using a fed-batch process with a novel airlift loop reactor. The reactor can be operated not... 相似文献
220.
A dual perturbation view of linear programming 总被引:2,自引:0,他引:2
Solving standard-form linear prograrns via perturbation of the primal objective function has received much attention recently. In this paper, we investigate a new perturbation scheme which obtains a dual optimal solution by perturbing the dual feasible domain under different norms. A dual-to-primal conversion formula is also provided. We show that this new perturbation scheme actually generalizes the primal entropic perturbation approach to linear programming.Partially sponsored by the North Carolina Supercomputing Center 1994 Cray Research Grant and the National Textile Center Research Grant. 相似文献