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31.
The in situ solvothermal reaction of 3,4-dicyano-1,2,5-thiadiazole with MCl(2) (M = Co, Ni) and NaOH afforded two isomorphous complexes, [M2(L)2(H(2)O)2]n (L = 2,1,3-thiadiazole-4,5-dicarboxylate), which exhibit a rare non-interpenetrated (10,3)-d (utp) network topology and interesting magnetic behaviors: spin-canted antiferromagnetism for the Co(II) complex, but simple antiferromagnetic coupling for the Ni(II).  相似文献   
32.
End-channel indirect amperometry is based on the principle of Kohlrausch regulating function (KRF). A dilute electroactive ionic species is added to the background electrolyte as a continuously eluting electrophore, which is used as probe. The probe concentration variation with the omega value of KRF in the sampling zone was described schematically in this report. Either cathodic or anodic electroosmotic flow (EOF) rates were monitored in microchip. There was no significant difference between the values of EOF rates measured by present method and current-monitoring method. Detection of electroactive and nonelectroactive analytes can also be accomplished by indirect amperometric method. Hence, the effective mobility of analytes can be accurately calculated. And the response mechanism of nonelectroactive analytes K(+), Na(+) and Li(+) in the indirect method was speculated.  相似文献   
33.
本文利用“Huber”解积分方程的方法计算了示差脉冲极谱(简称Dpp)吸附不可逆波方程,并讨论了该方程的性质。与文献采用的方法相比,该方程计算速度快、准确度高,有利于在微型计算机上实现。  相似文献   
34.
兰州放射性核束流线 *   总被引:4,自引:0,他引:4       下载免费PDF全文
描述了兰州重离子加速器国家实验室最近建成并已投入运行的新装置———兰州放射性核束流线 (RIBLL) .RIBLL是PF型双消色差反对称结构放射性核束分析设备 ,它的立体角接收度≥ 6 .5msr,动量接受度± 5 % ,最大磁刚度4.2Tm ,元素分辨>150 ,质量分辨>300 ,最短分辨时间 <1μs.初级束流的入射角在 0°~ 5°范围可调 .RIBLL已为第一批物理实验提供17N ,8He等多种放射性核束流 .  相似文献   
35.
Ivabradine hydrochloride (IVA‐HCl) (systematic name: {[3,4‐dimethoxybicyclo[4.2.0]octa‐1(6),2,4‐trien‐7‐yl]methyl}[3‐(7,8‐dimethoxy‐2‐oxo‐2,3,4,5‐tetrahydro‐1H‐3‐benzazepin‐3‐yl)propyl]methylazanium), is a novel medication used for the symptomatic management of stable angina pectoris. In many recent patents, it has been claimed to exist in a very large number of polymorphic, hydrated and solvated phases, although no detailed analysis of the structural features of these forms has been published to date. Here, we have successfully crystallized the tetrahydrate form of IVA‐HCl (form β), C27H37N2O5+·Cl?·4H2O, and elucidated its structure for the first time. Simultaneously, a new crystal form of IVA‐HCl, i.e. the hemihydrate (form II), C27H37N2O5+·Cl?·0.5H2O, was discovered. Its crystal structure was also accurately determined and compared to that of the tetrahydrate form. While the tetrahydrate form of IVA‐HCl crystallized in the orthorhombic space group P212121, the new form (hemihydrate) was solved in the monoclinic space group P21. Detailed conformational and packing comparisons between the two forms have allowed us to understand the role of water in the crystal assembly of this hydrochloride salt. The stabilities of the two forms were compared theoretically by calculating the binding energy of the water in the crystal lattice using differential scanning calorimetry (DSC). The stability experiments show that the tetrahydrate is stable under high‐humidity conditions, while the hemihydrate is stable under high‐temperature conditions.  相似文献   
36.
Reference-frame-independent quantum key distribution (RFI-QKD) has been demonstrated to be reliable and useful both in theories and experiments, which is intrinsically robust against slowly varying reference frames. In this paper, we propose an efficient scheme of passive decoy-state RFI-QKD based on the parametric down-conversion source, where a beam splitter splits the idler pulses into four local detection events to improve the performance of RFI-QKD systems. In addition, we demonstrate the worst relative rotation of reference frames in our scheme. Simulation results show that our scheme can achieve good performance even at the worst-case scenario.  相似文献   
37.
选择N-正丁基咔唑作为电子给体,芴酮作为桥键,苯甲酸作为受体,通过桥键芴酮与给体和受体连接位置的改变,设计合成了两个咔唑染料4-(6-(N-正丁基咔唑-3-基)-9-氧-9H-芴-3-基)苯甲酸(HXL-3W)和4-(7-(N-正丁基咔唑-3-基)-9-氧-9H-芴-2-基)苯甲酸(HXL-4Z).对咔唑染料的光谱性能、电化学性能和光电转换性能进行了研究,并运用密度泛函理论(DFT)方法对其几何结构和紫外-可见光谱进行了优化计算.结果表明, HXL-4Z的吸收光谱呈现两个明显的ππ*跃迁吸收峰和一个较小的对应于分子内电荷转移的吸收峰,而HXL-3W的吸收光谱则仅呈现一个ππ*跃迁吸收峰,且摩尔吸光系数远小于HXL-4Z.可能是HXL-3W分子结构中给体和受体距离较近,张力较大,导致较差的分子平面性和分子内电荷转移.因而HXL-4Z的光吸收能力和电子注入效率较优,从而具有较好的光电转换效率(2.03%) (短路电流(JSC) = 3.88 mA·cm-2,开路电压(VOC) = 700 mV,填充因子(FF) = 0.75).  相似文献   
38.
杨建荣  毛杰健 《物理学报》2009,58(6):3611-3616
根据变系数modified Korteweg-de Vries(VCmKdV)方程与常系数KdV-mKdV方程的非线性项、色散项的相似性,对解已知的KdV-mKdV方程做适当变换,并将它的解移植到解未知的VCmKdV方程,由此构造出两个不同方程解之间的移植关系.利用这种解的移植方法,求得了由两层流体模型经演化获得的含有源(或汇)耦合VCmKdV系统新的精确解和类孤波解.对Bcklund变换与解的移植法进行了比较,分析了源和汇对波幅的影响. 关键词: 解的移植法 KdV-mKdV方程 耦合VCmKdV系统 类孤波解  相似文献   
39.
The mass spectra of ground-state triply heavy baryons are systematically unscrambled and computed in QCD sum rules. With a tentative (QQ)–(Q)(QQ)(Q) configuration for QQQQQQ, the interpolating currents representing the triply heavy baryons are proposed. Technically, contributions of the operators up to dimension six are included in operator product expansion (OPE). The numerical results are presented in comparison with other theoretical predictions.  相似文献   
40.
PAN浊点萃取-火焰原子吸收光谱法测定水样中的痕量钴   总被引:14,自引:2,他引:12  
黄晖  肖珊美  陈建荣 《光谱实验室》2005,22(5):1003-1006
提出了浊点萃取-火焰原子吸收光谱法测定痕量钴的新方法。探讨了溶液pH,试剂浓度等实验条件对浊点萃取及测定灵敏度的影响。在最佳条件下,富集50mL样品溶液,用火焰原子吸收光谱法测定,钴的检出限为0.22μg/L,钴的富集倍率为68倍。方法用于自来水、井水及海水中痕量钴的测定。  相似文献   
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