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71.
Both the regional isomerization and selenium-substitution of the small molecular acceptors (SMAs) play significant roles in developing efficient organic solar cells (OSCs), while their synergistic effects remain elusive. Herein, we developed three isomeric SMAs (S-CSeF, A-ISeF, and A-OSeF) via subtly manipulating the mono-selenium substituted position (central, inner, or outer) and type of heteroaromatic ring on the central core by synergistic strategies for efficient OSCs, respectively. Crystallography of asymmetric A-OSeF presents a closer intermolecular π–π stacking and more ordered 3-dimensional network packing and efficient charge-hopping pathways. With the successive out-shift of the mono-selenium substituted position, the neat films give a slightly wider band gap and gradually higher crystallinity and electron mobility. The PM1 : A-OSeF afford favourable fibrous phase separation morphology with more ordered molecular packing and efficient charge transportation compared to the other two counterparts. Consequently, the A-OSeF-based devices achieve a champion efficiency of 18.5 %, which represents the record value for the reported selenium-containing SMAs in binary OSCs. Our developed precise molecular engineering of the position and type of selenium-based heteroaromatic ring of SMAs provides a promising synergistic approach to optimizing crystal stacking and boosting top-ranked selenium-containing SMAs-based OSCs.  相似文献   
72.
史良伟  武文明  强洪夫  陈敏伯 《化学学报》2008,66(23):2579-2584
采用最大熵模型, 构建了HTPB预聚物的最可几结构. 考察了HTPB (nC=9)与TDI全混合以及半混合的两种固化建模方式. 分子动力学模拟得到的HTPB (nC=9)-TDI固化网络的N—N径向分布函数显示半混模式比全混模式的结构更均匀. 采用分子动力学动态模拟与静态拉伸方法对HTPB (nC=9)-TDI固化网络进行弹性力学性质的模拟计算. 比较了半混和全混模式对拉伸模量计算的影响, 表明半混模式得到的固化网络能得到合理的模拟结果. 初步表明最大熵模型在研究HTPB固化问题上静态或动态模拟结果都具有唯象可行性.  相似文献   
73.
纳米复合Sb_2O_3/TiO_2的光催化性能研究   总被引:7,自引:0,他引:7  
采用溶胶-凝胶法制备复合纳米 Sb2O3/TiO2。 Sb2O3掺入浓度越大,催化剂中锐钛矿相含量越高,晶粒直径与颗粒直径越小,比表面积越大。在 380~ 460nm范围内, Sb2O3/TiO2的反射率则减弱,表明光吸收增强。 XPS分析表明:掺入 2% Sb2O3,出现新的 Ti2p3/2峰,对应于 Ti3+,占 9.13%;锑以 Sb3+、 Sb5+两种形式存在, Sb5+占 84.42%、 Sb3+占 17.58%。以亚甲基蓝溶液光催化降解为模型反应,掺入 2%、 5% Sb2O3,亚甲基蓝溶液的光催化脱色降解一级动力学常数与总有机炭( TOC)去除率增大。发射光谱证明: Sb2O3的最佳比例为 2%,当其比例大于 2%时,其电子空穴对的复合率升高,光催化活性下降。  相似文献   
74.
We explore some interesting phenomena in a simple non-Hermitian ladder system. Special modes with energy eigenvalues closely related to the inter-chain-coupling strength appear in the non-Hermitian ladder system. We show that a phase transition occurs whereby special modes with pure real eigenvalues can switch to special modes with pure imaginary eigenvalues, when the inter-chain-coupling strength changes from symmetric to asymmetric. We find that the density profiles of all the special modes are completely identical under certain conditions, even if the inter-chain-coupling strength is added into the non-Hermitian ladder system in different ways. Moreover, we also demonstrate that the different inter-chain couplings are fundamentally equivalent to adding different on-site potential energies into the non-Hermitian ladder system.  相似文献   
75.
We propose a protocol to implement the nonlocal Bell-state measurement, which is nearly determinate with the help of weak cross-Kerr nonlinearities and quantum non-destructive photon number resolving detection. Based on the nonlocal Bell-state measurement, we implement the quantum information transfer from one place to another. The process is different from conventional teleportation but can be regarded as a novel form of teleportation without entangled channel and classic communication.  相似文献   
76.
赵瑞通  郭奇  陈丽  王洪福  张寿 《中国物理 B》2012,21(8):80303-080303
We present a scheme for quantum superdense coding with hyperentanglement,in which the sender can transfer four bits of classical information by sending only one photon.The important device in the scheme is the hyperentangled Bell-state analyzer in both polarization and frequency degrees of freedom,which is also constructed in the paper by using a quantum nondemolition detector assisted by cross-Kerr nonlinearity.Our scheme can transfer more information with less resources than the existing schemes and is nearly deterministic and nondestructive.  相似文献   
77.
王洪福  张寿 《中国物理 B》2012,21(10):100309-100309
Clock synchronization is a well-studied problem with many practical and scientific applications.We propose an arbitrary accuracy iterative quantum algorithm for distributed clock synchronization using only three qubits.The n bits of the time difference between two spatially separated clocks can be deterministically extracted by communicating only O(n) messages and executing the quantum iteration process n times based on the classical feedback and measurement operations.Finally,we also give the algorithm using only two qubits and discuss the success probability of the algorithm.  相似文献   
78.
纳米复合Sb2O3/TiO2的光催化性能研究   总被引:37,自引:0,他引:37  
采用溶胶-凝胶法制备复合纳米Sb2O3/TiO2Sb2O3掺入浓度越大,催化剂中锐钛矿相含量越高,晶粒直径与颗粒直径越小,比表面积越大,在380-460nm,范围内,Sb2O3/TiO2的反射率则减弱,表明光吸收增强,Sb^5+,占48.42%、Sb^ 占17.58%,以亚甲基蓝溶液光催化降解为模型反应,掺入2%,5%Sb2O3,亚在蓝溶液的光催化脱色降解一致动力学常数与总有机炭(TOC)去除率增大,发射光谱证明,Sb2O3的最佳比例为2%,当其比例大于2%时,其电子空穴对的复合率升高,光催化活性下降。  相似文献   
79.
慢性肾功能衰竭是指在各种慢性肾脏疾病的基础上,缓慢出现肾功能减退而不可逆转的肾衰竭综合症由于患者肾功能衰竭,使得一些正常人本可以排出体外的代谢产物滞留在体内,导致肌体的一系列病变,涉及到人体的肠胃、免疫、心血管、内分泌、皮肤和骨骼等各个系统.20世纪70年代以来,中分子物质在患者体内的毒性作用开始引起众多研究者的关注.然而,由于这类物质成分复杂,对其分离鉴定工作还面临着很多困难,它们与慢性肾衰患者的临床症状之间的因果关系及致病机理仍不甚明确.在前期研究中,我们采用凝胶色谱法分离尿毒症患者血清,得到两个中分子物质峰A和B,  相似文献   
80.
高丹  赵振双  朱爱东  王洪福  邵晓强  张寿 《中国物理 B》2010,19(9):90313-090313
This paper studies the average fidelity of teleportation and thermal entanglement for a two-qubit Heisenberg X Y Z chain in the presence of both an inhomogeneous magnetic field and a Dzyaloshinski-Moriya interaction. It shows that for a fixed Dz, the increase of bz will broaden the critical temperature at the cost of decreasing the thermal entanglement. And it can modulate the inhomogeneous magnetic field and the Dzyaloshinski-Moriya interaction for the average fidelity of teleportation to be optimal.  相似文献   
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