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排序方式： 共有2749条查询结果，搜索用时 15 毫秒
941.
Yujing Zhang Xiyuan Li Jongwoon Kim Yuxin Tong Emily G. Thompson Shan Jiang Ziang Feng Li Yu Jinhua Wang Dong Sam Ha Harald Sontheimer Blake N. Johnson Xiaoting Jia 《Advanced Optical Materials》2021,9(6):2001815
Highly stretchable fiber sensors have attracted significant interest recently due to their applications in wearable electronics, human–machine interfaces, and biomedical implantable devices. Here, a scalable approach for fabricating stretchable multifunctional electrical and optical fiber sensors using a thermal drawing process is reported. The fiber sensors can sustain at least 580% strain and up to 750% strain with a helix structure. The electrical fiber sensor simultaneously exhibits ultrahigh stretchability (400%), high gauge factors (≈1960), and excellent durability during 1000 stretching and bending cycles. It is also shown that the stretchable step-index optical fibers facilitate detection of bending and stretching deformation through changes in the light transmission. By combining both electrical and optical detection schemes, multifunctional fibers can be used for quantifying and distinguishing multimodal deformations such as bending and stretching. The fibers’ utility and functionality in sensing and control applications are demonstrated in a smart glove for controlling a virtual hand model, a wrist brace for wrist motion tracking, fiber meshes for strain mapping, and real-time monitoring of multiaxial expansion and shrinkage of porcine bladders. These results demonstrate that the fiber sensors can be promising candidates for smart textiles, robotics, prosthetics, and biomedical implantable devices. 相似文献
942.
Dr. Nichole S. Liebov Dr. Jonathan M. Goldberg Dr. Nicholas C. Boaz Dr. Nathan Coutard Dr. Steven E. Kalman Thompson Zhuang Prof. John T. Groves Prof. T. Brent Gunnoe 《ChemCatChem》2019,11(20):5045-5054
Partial oxidation of light alkanes to generate alkyl esters has been achieved under photochemical conditions using mixtures of iodine oxides and chloride salts in trifluoroacetic acid (HTFA). The reactions are catalytic in chloride and are successful using compact fluorescent light, but higher yields are obtained using a mercury lamp. In this photo-initiated oxyesterification process, the robust alkyl ester products are resistant to over-oxidation, and under optimized conditions yields for alkyl ester production of ∼50 % based on methane, ∼60 % based on ethane (with a total functionalized yield of EtX (X=TFA or Cl) of 80 %) and ∼30 % based on propane have been demonstrated. The reaction also proceeds in aqueous HTFA and dichloroacetic acid with lower yields. Mechanistic studies indicate that the process likely operates by a chlorine hydrogen atom abstraction pathway wherein alkyl radicals are generated, trapped by iodine, and converted to alkyl trifluoroacetates in situ. 相似文献
943.
944.
Cody Masters Jocelyn Dolphin April Maschmann Keegan McGill Matthew Moore Drew Thompson Kristy L. Kounovsky‐Shafer 《Electrophoresis》2019,40(5):810-816
To understand structural variation for personal genomics, an extensive ensemble of large DNA molecules will be required to span large structural variations. Nanocoding, a whole‐genome analysis platform, can analyze large DNA molecules for the construction of physical restriction maps of entire genomes. However, handling of large DNA is difficult and a system is needed to concentrate large DNA molecules, while keeping the molecules intact. Insert technology was developed to protect large DNA molecules during routine cell lysis and molecular biology techniques. However, eluting and concentrating DNA molecules has been difficult in the past. Utilizing 3D printed mesofluidic device, a proof of principle system was developed to elute and concentrate lambda DNA molecules at the interface between a solution and a poly‐acrylamide roadblock. The matrix allowed buffer solution to move through the pores in the matrix; however, it slowed down the progression of DNA in the matrix, since the molecules were so large and the pore size was small. Using fluorescence intensity of the insert, 84% of DNA was eluted from the insert and 45% of DNA was recovered in solution from the eluted DNA. DNA recovered was digested with a restriction enzyme to determine that the DNA molecules remained full length during the elution and concentration of DNA. 相似文献
945.
In previous papers we have shown that a semi-empirical thermodynamic—diffusive model appears to duplicate the behavior of the hexane/heptane/polyethylene system with regard to the effect of upstream and downstream pressure on rate and separation. In the present paper we present a numerical method for dealing with our model equations, which allows us to treat nonideal systems, and to make use of more general expressions describing the concentration dependence of diffusivity. This method is discussed in detail, and several typical simulation results are presented. 相似文献
946.
M. C. Fujiwara G. Andresen W. Bertsche A. Boston P. D. Bowe C. L. Cesar S. Chapman M. Charlton M. Chartier A. Deutsch J. Fajans R. Funakoshi D. R. Gill K. Gomberoff J. S. Hangst W. N. Hardy R. S. Hayano R. Hydomako M. J. Jenkins L. V. Jørgensen L. Kurchaninov N. Madsen P. Nolan K. Olchanski A. Olin R. D. Page A. Povilus F. Robicheaux E. Sarid D. M. Silveira J. W. Storey R. I. Thompson D. P. van der Werf J. S. Wurtele Y. Yamazaki 《Hyperfine Interactions》2006,172(1-3):81-89
ALPHA is an international project that has recently begun experimentation at CERN’s Antiproton Decelerator (AD) facility.
The primary goal of ALPHA is stable trapping of cold antihydrogen atoms with the ultimate goal of precise spectroscopic comparisons
with hydrogen. We discuss the status of the ALPHA project and the prospects for antihydrogen trapping. 相似文献
947.
R. C. Thompson 《Linear and Multilinear Algebra》1991,30(4):315-316
This section appears from time to time. Contributions are invited, and should be submitted to Robert c.Thompson, Mathematics Department,University of California, Santa Barbara, CA 93106, USA. 相似文献
948.
949.
This paper outlines the general principles of constructing mathematical programming models of the market formation for one or several goods in the presence of rigid prices. For the purpose of exposition, it is assumed that each good may be traded internationally and that the domestic price of the good is bounded from above by its import price and from below by its export price. In principle, however, any other institutional factor causing prices to be rigid can be dealt with in a similar manner.The Lagrange multiplier of the market balance of the good can be interpreted as its market price. From a mathematical point of view, one is confronted with a class of mathematical programming problems wherea priori upper and lower bounds have been imposed upon the Lagrange multipliers. 相似文献
950.