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21.
In this paper, we consider the optimization of the quantum circuit for discrete logarithm of binary elliptic curves under a constrained connectivity, focusing on the resource expenditure and the optimal design for quantum operations such as the addition, binary shift, multiplication, squaring, inversion, and division included in the point addition on binary elliptic curves. Based on the space-efficient quantum Karatsuba multiplication, the number of CNOTs in the circuits of inversion and division has been reduced with the help of the Steiner tree problem reduction. The optimized size of the CNOTs is related to the minimum degree of the connected graph.  相似文献   
22.
Numerous experiments have revealed that fullerene (C60) and its derivatives can bind to proteins and affect their biological functions. In this study, we explored the interaction between fullerine and the β2-adrenergic receptor (β2AR). The MD simulation results show that fullerene binds with the extracellular loop 2 (ECL2) and intracellular loop 2 (ICL2) of β2AR through hydrophobic interactions and π–π stacking interactions. In the C60_in1 trajectory, due to the π–π stacking interactions of fullerene molecules with PHE and PRO residues on ICL2, ICL2 completely flipped towards the fullerene direction and the fullerene moved slowly into the lipid membrane. When five fullerene molecules were placed on the extracellular side, they preferred to stack into a stable fullerene cluster (a deformed tetrahedral aggregate), and had almost no effect on the structure of β2AR. The hydroxyl groups of fullerene derivatives (C60(OH)X, X represents the number of hydroxyl groups, X = 4, 8) can form strong hydrogen bonds with the ECL2, helix6, and helix7 of β2AR. The hydroxyl groups firmly grasp the β2AR receptor like several claws, blocking the binding entry of ligands. The simulation results show that fullerene and fullerene derivatives may have a significant effect on the local structure of β2AR, especially the distortion of helix4, but bring about no great changes within the overall structure. It was found that C60 did not compete with ligands for binding sites, but blocked the ligands’ entry into the pocket channel. All the above observations suggest that fullerene and its derivatives exhibit certain cytotoxicity.  相似文献   
23.
As the most advanced aerogel material, silica aerogel has had transformative industrial impacts. However, the use of silica aerogel is currently limited to the field of thermal insulation materials, so it is urgent to expand its application into other fields. In this work, silica aerogel/resin composites were successfully prepared by combining silica aerogel with a resin matrix for dental restoration. The applications of this material in the field of dental restoration, as well as its performance, are discussed in depth. It was demonstrated that, when the ratio of the resin matrix Bis-GMA to TEGDMA was 1:1, and the content of silica aerogel with 50 μm particle size was 12.5%, the composite achieved excellent mechanical properties. The flexural strength of the silica aerogel/resin composite reached 62.9546 MPa, which was more than five times that of the pure resin. Due to the presence of the silica aerogel, the composite also demonstrated outstanding antibacterial capabilities, meeting the demand for antimicrobial properties in dental materials. This work successfully investigated the prospect of using commercially available silica aerogels in dental restorative materials; we provide an easy method for using silica aerogels as dental restorative materials, as well as a reference for their application in the field of biomedical materials.  相似文献   
24.
Carbon nanotubes (CNTs) are excellent scaffolds for advanced electrode materials, resulting from their intrinsic sp2 carbon hybridization, interconnected electron pathway, large aspect ratio, hierarchical porous structures, and low cost at a large-scale production. How to make full utilization of the mass produced CNTs as building blocks for nanocomposite electrodes is not well understood yet. Herein, a composite cathode containing commercial agglomerated multi-walled CNTs and S for Li-S battery was fabricated by a facile melt-diffusion strategy. The hierarchical CNT@S coaxial nanocables exhibited a discharging capacity of 1020 and 740 mAh g-1 at 0.5 and 2.0 C, respectively. A rapid capacity decay of 0.7% per cycle at the initial 10 cycles and a slow decay rate of 0.14% per cycle for the later 140 cycles were detected. Such hierarchical agglomerated CNT@S cathodes show advantages in easy fabrication, environmentally benign, low cost, excellent scalability, and good Li ion storage performance, which are extraordinary composites for high performance Li-S battery.  相似文献   
25.
ABSTRACT

Five multivalent β-D-GalNAc-(1→4)-β-D-Gal oligomers were selected and synthesized as probes for investigating the adhesin-receptor interactions of P. aeruginosa pili with multivalent receptors. They were synthesized by the amide coupling reactions of 8-(N-2-aminoethyl)carboxamidooctyl 4-O-(2-acetamido-2-deoxy-β-D-galactopyranosyl)-β-D-galactopyranoside (7) with EDTA dianhydride, EDTA, Kemp's triacid and adipic acid with EDC, DIC and DCC combined with HOBt as coupling reagents and by the reaction of per-O-acetylated 7 with 1,3,5-benzenetricarbonyl trichloride followed by de-O-acetylation. These resulting multivalent compounds contain flexible C9 spacer arms as linkers attached to either flexible hydrophilic moieties or rigid hydrophobic cores.  相似文献   
26.
We report the synthesis and characterization of a polythiophene block copolymer (P4) selectively functionalized with diaminopyrimidine moieties and a thymine tethered fullerene derivative (F1). Self‐assembly between P4 and F1 through “three‐point” complementary hydrogen bonding is studied by 1H NMR spectroscopy and differential scanning calorimetry. A large Stern‐Volmer constant (KSV) of 1.2 × 105 M?1 is observed from fluorescence quenching experiments, revealing strong complexation between these two components. Solar cells employing P4 and F1 at different weight ratios as active layers are fabricated and tested; corresponding thin film morphologies are studied in detail by optical imaging and atomic force microscopy. Correlations between polymer complex structures, film morphologies, and device performance are discussed. Thermal stability of benchmark poly(3‐hexylthiophene) bulk heterojunction solar cells is found to be improved by the addition of a few weight percent of P4/F1 complexes as compatibilizers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3339–3350  相似文献   
27.
28.
胡逸群  费跃平 《光学学报》1994,14(6):26-631
讨论了横向位移双曝光散斑图维纳谱的信息分布,并由此导出杨氏纹图的一般表达式。讨论了条纹可见度与应变,面内转动,照明光束直径与条纹图图空间坐标的关系,指出了在条纹可见度影响下最大可见条纹数目。还讨论了散斑衬比与衍射晕的关系。  相似文献   
29.
介绍了由于磁铁的安装误差和螺线管的存在而造成的束流径向和轴向的耦合,以及耦合对束流稳定的影响。结合CSRm结构的典型参数分析得出:二极磁铁和四极磁铁在纵向角安装偏差为-0.5~0.5 mrad;有螺线管存在的情况下,工作点落在和共振线时,将导致束流不稳定而大量损失,落在差共振线时,束流稳定。通过模拟计算发现:螺线管产生的耦合远大于磁铁的纵向角安装偏差产生的耦合。  相似文献   
30.
刘晓宙  朱忆  张飞  龚秀芬 《中国物理 B》2013,22(2):24301-024301
In most previous models,simulation of the temperature generation in tissue is based on the Pennes bio-heat transfer equation,which implies an instantaneous thermal energy deposition in the medium.Due to the long thermal relaxation time τ(20 s-30 s) in biological tissues,the actual temperature elevation during clinical treatments could be different from the value predicted by the Pennes bioheat equation.The thermal wave model of bio-heat transfer(TWMBT) defines a thermal relaxation time to describe the tissue heating from ultrasound exposure.In this paper,COMSOL Multiphysics 3.5a,a finite element method software package,is used to simulate the temperature response in tissues based on Pennes and TWMBT equations.We further discuss different factors in the bio-heat transfer model on the influence of the temperature rising and it is found that the temperature response in tissue under ultrasound exposure is a rising process with a declining rate.The thermal relaxation time inhibits the temperature elevation at the beginning of ultrasonic heating.Besides,thermal relaxation in TWMBT leads to lower temperature estimation than that based on Pennes equation during the same period of time.The blood flow carrying heat dominates most to the decline of temperature rising rate and the influence increases with temperature rising.On the contrary,heat diffusion,which can be described by thermal conductivity,has little effect on the temperature rising.  相似文献   
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