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991.
Microfluidic droplets have emerged as novel platforms for chemical and biological applications. Manipulation of droplets has thus attracted increasing attention. Different from solid particles, deformable droplets cannot be efficiently controlled by inertia-driven approaches. Here, we report a study on the lateral migration of dual droplet trains in a double spiral microchannel at low Reynolds numbers. The dominant driving mechanism is elucidated as wall effect originated from the droplet deformation. Three types of migration modes are observed with varying Reynolds numbers and the size-dependent mode is intensively investigated. We obtain empirical formulas by relating the migration to Reynolds numbers and droplet sizes. The effect of droplet deformability on the migration and the detailed migration behavior along the double spiral channel are discussed. Numerical simulations are also performed and yielded in qualitative agreement with the experiments. This proposed low Re approach based on lateral migration could be a promising alternative to existing inertia-driven approaches especially concerning deformable entities and susceptible bio-particles.  相似文献   
992.
993.
994.
The catalytic enantioselective diorganozinc additions to cyclic diketones including pyrazolin-4,5-diones and isatins have been developed. In the presence of morpholine-containing chiral amino alcohol ligand, the corresponding chiral cyclic tertiary alcohols were produced in good to excellent yields (up to 97 %) and enantioselectivities (up to 95 % ee). The notable feature of this protocol includes its mild reaction conditions, Lewis acid additives free and broad functional group tolerance.  相似文献   
995.
Lu  Yuchan  He  Qiao  Peng  Qiao  Chen  Wenhai  Cheng  Qunpeng  Song  Guangsen  Fan  Guozhi 《Cellulose (London, England)》2021,28(13):8343-8354
Cellulose - The coproduction of 5-hydroxymethylfurfural (5-HMF) and furfural (FUR) via the direct hydrolysis of holocellulose analogue composed of cellulose and hemicellulose was investigated. The...  相似文献   
996.
Heting Li  Xin Wang  Chao Zheng 《合成通讯》2013,43(14):1933-1940
A simple and efficient synthetic route of 2′‐amino‐2′‐deoxyuridine was studied. 2′‐Amino‐2′‐deoxyuridine was incorporated into 1,8‐naphthalimides in the 2′‐position of 2′‐sugar via linking arms of different lengths. A convenient method for the synthesis of the conjugates was adopted.  相似文献   
997.
998.
Yong He 《Optics Communications》2010,283(7):1558-1560
We propose a scheme to generate a type of genuine four-qubit entangled states, which were firstly introduced by Yeo et al. [Y. Yeo, W. K. Chua, Phys. Rev. Lett. 96 (2006) 060502]. These states have many interesting entanglement properties and possess possible applications in quantum information processing and in fundamental tests of quantum physics. We show that such a type of 16 orthonormal basis states can be deterministically distinguished by a cavity QED system.  相似文献   
999.
The development of dependable, environmentally benign processes for the synthesis of nanoscale materials is an important aspect of nanotechnology. In the present study, we report one-pot biogenic fabrication of palladium nanoparticles by a simple procedure using broth of Cinnamomum camphora leaf without extra surfactant, capping agent, and/or template. The mean size of palladium nanoparticles, ranging from 3.2 to 6.0 nm, could be facilely controlled by merely varying the initial concentration of the palladium ions. The polyols components and the heterocyclic components were believed to be responsible for the reduction of palladium ions and the stabilization of palladium nanoparticles, respectively.  相似文献   
1000.
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