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991.

In this paper, an improved controlled bidirectional quantum teleportation protocol of the special three-qubit state is proposed. In a little bit more detail, under the control of the third supervisor Charlie, Alice wants to send one special three-qubit entangled state to Bob, and at the meantime, Bob also wants to transmit another special three-qubit entangled state to Alice. In other words, both Alice and Bob can be the sender and receiver simultaneously. To achieve this aim, a specific eleven-qubit entangled state is shared among Alice, Bob and Charlie in advance acting as the quantum channel. Then, Alice and Bob first implement the GHZ-state measurement and Bell-state measurement respectively, and following Charlie’s single-qubit measurement. Finally, upon the foregoing measurement results, Alice and Bob can respectively implement the specific unitary operators on their local particles to recover the initial state transmitted by the other.

  相似文献   
992.
俞冰昊  郝强  曾和平 《光学学报》2021,41(19):265-269
实验搭建了基于分离脉冲放大及光纤非线性压缩的掺铒光纤激光系统.通过三块长度倍增的YVO4晶体进行偏振复用,实现了八脉冲的分离与合成.探究了不同脉冲宽度的注入条件下分离脉冲主放大器的合成效率.将放大后的脉冲耦合入一段单模保偏光纤中进行非线性压缩,通过控制主放大器的抽运光功率和压缩器的光纤长度,对非线性压缩过程进行优化,获得了重复频率为80.4 MHz、平均功率为510 mW、脉冲宽度为55 fs的超短脉冲.最后,采用MgO∶PPLN晶体进行光学倍频处理,在中心波长783.4 nm处获得了平均功率为146 mW、脉冲宽度为75 fs的倍频光,相应的倍频效率为31%.  相似文献   
993.
环形磁场金属等离子体源作为一种全新的等离子体源结构,可用于产生高度离化、无大颗粒、高密度的离子束流,但传统流道结构不能保证其高效、均匀散热,大功率工作时可能引起密封胶圈的烧蚀失效,需对其冷却流场进行优化设计.利用Solidworks Flow Simulation软件对等离子体源冷却流道进行模拟,分析出入水孔分布角度、孔数、孔径以及入水孔高度对冷却效果的影响规律,并对流道结构参数进行优化.结果表明,增大水孔的周向分布范围,有利于提高散热的均匀性;入水孔设置在结构上层有利于减少冷却水的温度分层现象,使铜套和密封胶圈都处于较好的冷却状态;适当减小孔径有利于增大冷却水射流速度,增大湍流程度强化传热,提高换热效率.优化后的流场结构可以提高冷却水的利用率,在相同流量条件下获得更好的冷却效果,改善等离子体源的放电稳定性,为环形磁场金属等离子体源的冷却结构设计提供理论依据.  相似文献   
994.
采用熔融-淬冷法制备了Tb3+掺杂锂铝硅酸盐闪烁玻璃,用紫外激发光谱、发射光谱及荧光寿命表征了光致发光性能,用X射线和阴极射线激发测试了辐射致发光性能。研究结果表明:低Tb3+掺杂浓度时,随着其浓度增大,Tb3+间的交叉弛豫增加导致了5D3→7Fj跃迁的能量逐渐向5D4→7Fj迁移转变,5D3激发态的荧光寿命和发射强度均明显下降,5D4-7Fj发射强度逐渐增大。较高Tb3+浓度时,其浓度继续增加会提升非辐射比例,是荧光寿命降低和荧光猝灭的最主要原因。比较光致发光和辐照致发光性能,发现随着激发源的能量上升,会增加激发态5D3能级向5D4能级的能量转移,同时,由于玻璃的密度低会导致辐照致发光效率随激发源的能量上升而下降。  相似文献   
995.
Two complexes based on the ligand 1,4‐dihydro‐2,3‐quinoxalinedione, namely [Mn(H2L)2(H2O)2]n ( 1 ) and {[Zn2(H2L)2(tz)2] · 5H2O}n ( 2 ) (H3L = 2,3‐dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic acid, Htz = 1,2,4‐triazole) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, as well as single‐crystal and powder X‐ray diffraction. Complex 1 exhibited a 1D comb‐like chain formed by H2L anions linking MnII ions, whereas complex 2 was a 2D layer‐like structure with square‐shaped windows and outstretched arms built by combination of H2L and tz ligands with ZnII ions. The adjacent chains or layers connected with each other by intermolecular hydrogen bonding and π–π stacking to further extend to a 3D supermolecular framework. In addition, the thermal stabilities, luminescence properties, and optical energy gap of 1 and 2 were investigated in detail.  相似文献   
996.
A series of novel dinuclear platinum(II) complexes with a chiral tetradentate ligand, (1R,1′R,2R,2′R)-N1,N1′-(1,2-phenylenebis(methylene))dicyclohexane-1,2-diamine (HL), and mono-carboxylic acid derivatives as ligands have been designed, synthesized, and characterized. In vitro cytotoxicity evaluation of synthesized complexes against human HepG-2, A549, HCT-116, and MCF-7 cancer cell lines has been conducted by MTT assays. All compounds showed antitumor activity to HepG-2 and HCT-116 cell lines. Compound L2 exhibited better cytotoxicity than that of carboplatin against HepG-2 and A549 cell lines and also showed comparable activity against HCT-116 cell line.  相似文献   
997.
998.
An off-line orthogonal two-dimensional preparative liquid chromatography method was developed for isolation of high-purity compounds from aqueous extracts of Pinus massoniana Lamb., which has efficient therapeutic properties in recipes of traditional Chinese medicines. A polar-enhanced reversed-phase (RP) column, XAqua C18 was selected for the first-dimensional separation. A HILIC column and a hydrophobic RP column were both explored in the second dimension. The preparation results indicated hydrophilic RP × HILIC mode would provide better separation efficiency for polar complexes, i.e., the second-dimensional separation was finished in less than 30 min and high-purity compounds were obtained. In this work, 16 fractions were collected efficiently in the first dimension with a recovery up to 96%, and six compounds with high purity and enough quantity were identified by NMR and high resolution mass spectrometry, including epicatechin, betuloside, taxifolin-3-O-xyloside, cedrusin-4-O-glucoside, massonianoside C and massonianoside D, and five are glycosides, including flavonoid glycosides, lignanoid glycosides and an arylbutanoid glycoside. Betuloside was first reported in the preparation of Pinus massoniana Lamb. This work demonstrated a flexible strategy of compromise in between time and resolution for selecting solvent and column to enhance preparative efficiency of polar complex systems.  相似文献   
999.
The authors describe a signal amplification strategy for highly sensitive detection of the prostate-specific antigen (PSA). This is accomplished by a combination of two methods, viz. (a) improved surface-initiated enzymatic polymerization (SIEP), and (b) the use of nanoflowers prepared from C60 fullerene and Methylene Blue (C60/MB) modified with a long single-strand DNA. C60/MB acts as a novel electrochemical indicator. The C60/MB nanoflowers improve the load of MB and promote the electron transfer. The integration of the SIEP technique and the C60/MB nanomaterial also results in improved loading of MB on the nucleic acid. Ultimately, dual cascade signal amplification is accomplished. The biosensor was constructed as follows: (a) Gold nanospheres were modified with antibody 2 (Ab2) and a thiolated oligonucleotide (referred to as S0). (2) S0 is then extended by the SIEP reaction. (3) The redox indicator C60/MB is then connected to the extended guanine-rich ssDNA which then yields the amperometric signal. (4) A sandwich immunoassay is performed by capturing the nanoprobe oy type Ab2-Au-S0 on the gold electrode modified with multi-walled carbon nanotubes (MWCNTs) and protein A. Current is measured by using differential pulse voltammetry (DPV). The synergic effect of the biofunctional nanomaterial and the signal amplification strategy greatly improves the performance of this immunoassay. Under optimized conditions and at a working voltage of typically ?0.18 V (vs Ag/AgCl), the assay has a linear range that extends from 15 pg·mL?1 to 8 ng·mL?1 of PSA. The detection limit is as low as 1.7 pg·mL?1 (at an S/N ratio of 3). In our perception, this dual amplification scheme has a wide scope in that it may become applicable to numerous other immunoassays.
Graphical abstract C60/Methylene blue nanoflowers, a novel electrochemical indicator, connect with the long single-stranded DNA (ssDNA) extended by the improved surface-initiated enzymatic polymerization method. This amplification strategy is utilized to construct a sandwich prostate-specific antigen (PSA) immunosensor.
  相似文献   
1000.
30R- and 30S-oxazoline analogues of apratoxin E have been prepared with late-stage formation of an oxazoline ring. These two compounds have a potent inhibitory effect on HCT-116 cell proliferation with IC50 values of 345 and 638 nM, respectively. These results suggest that apratoxin E oxazoline bioisosteres are approximately 6-fold less potent than their thiazoline parent compounds. A positive impact of the 30R conformation on antiproliferative activity was also observed, with approximately 2-fold enhancement when compared to the 30S epimer.  相似文献   
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