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排序方式: 共有8093条查询结果,搜索用时 15 毫秒
991.
Numerical Algorithms - This paper presents a class of low memory quasi-Newton methods with standard backtracking line search for large-scale unconstrained minimization. The methods are derived by... 相似文献
992.
Shuangshuang Long Weijie Chi Lu Miao Qinglong Qiao Xiaogang Liu Zhaochao Xu 《中国化学快报》2019,30(3):601-604
Both experimental and computational studies showed owing to strong π-π stacking interactions, 1-acetylpyrene mainly exists in dimers and molecular aggregates even at low concentrations, which led to the mis-assignment of its monomer emission peaks. 相似文献
993.
Yun Bai Huaiyu Wang Jianghua He Yuetao Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11710-11716
An immortal N-(diphenylphosphanyl)-1,3-diisopropyl-4,5-dimethyl-1,3-dihydro-2H-imidazol-2-imine/diisobutyl (2,6-di-tert-butyl-4-methylphenoxy) aluminum (P(NIiPr)Ph2/(BHT)AliBu2)-based frustrated Lewis pair (FLP) polymerization strategy is presented for rapid and scalable synthesis of the sequence-controlled multiblock copolymers at room temperature. Without addition of extra initiator or catalyst and complex synthetic procedure, this method enabled a tripentacontablock copolymer (n=53, k=4, dpn=50) to be achieved with the highest reported block number (n=53) and molecular weight (Mn=310 kg mol−1) within 30 min. More importantly, this FLP polymerization strategy provided access to the multiblock copolymers with tailored properties by precisely adjusting the monomer sequence and block numbers. 相似文献
994.
JingWei Wen XiaoCong Qiu XiangYu Kong XinYu Chen Fan Yang GuiLu Long 《中国科学:物理学 力学 天文学(英文版)》2020,(3):112-115
Quantum computing is an emerging and promising research field in modern quantum physics and is committed to accelerating traditional calculation processes using the principle of quantum mechanics[1,2].Several computation models have been proposed,including the circuit model[3],topologic quantum computation[4],adiabatic quantum computing[5],and duality quantum computing[6-8].Universal quantum computation generally includes a system initialization,evolutionary control,and a final-state readout[9],where the preparation of the initial state is a key step in the entire process. 相似文献
996.
Zhang Yi Huang Peng Long Mei Liu Song Yang Huaming Yuan Shuwen Chang Shi 《中国科学:化学(英文版)》2019,62(1):58-61
An innovative cancer therapy strategy regarding the interface engineering of kaolinite has been designed. The exposed silanol group facilitates more guest species with high dispersion on the supports. Mn_3O_4 magnetic nanoparticles are uniformly distributed on external surfaces of the Kaolin_(C12N)with the Al–O–Mn bond for the detection of the tumor microenvironment by T1-MRI; Doxorubicin(DOX) are loaded in the interlayer space with the electrostatic interaction for chemo-treating; and KI is coated on the outer layer of the nanocomposites based on the electrostatic interaction for thyroid cancer targeting. The synergetic effects and the treatment mechanism enhanced by the interface engineering, KI@DOX-Mn_3O_4-Kaolin_(C12N)can cause remarkably low cell viability(57%, 200 μg/mL), tumor shrinking(75%, 20 μg/kg), and accumulation into the tumor tissues. The novel kaolinite based drug delivery system is expected to incorporate imaging diagnosis, targeted therapy and drug delivery into one single system for postoperative residual thyroid cancer treatment and observation for metastasis of focal area. 相似文献
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Dr. Huixin Fan Prof. Chensheng Lin Kaichuang Chen Dr. Guang Peng Dr. Bingxuan Li Prof. Ge Zhang Prof. Xifa Long Prof. Ning Ye 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5306-5310
An ammonium-containing metal iodate fluoride compound, (NH4)Bi2(IO3)2F5, featuring a two-dimensional double-layered framework constructed by [BiO2F5]6− and [BiO4F4]9− polyhedra, as well as [IO3]− groups, was successfully synthesized. The well-ordered alignment of these SHG-active units leads to an extraordinary strong SHG response of 9.2 times that of KDP. Moreover, this compound possesses a large birefringence (Δn=0.0690 at 589.3 nm), a wide energy band gap (Eg=3.88 eV), and a high laser damage threshold (LDT; 40.2×AgGaS2). In particular, thermochromic behavior was observed for the first time in this type of compound. Such multifunctional crystals will expand the application of nonlinear optical materials. 相似文献