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Two novel aryl glycosides were synthesized, which varied in the extent of unsaturation in the lipophilic part, from plant/crop-based renewable resource materials. Their liquid crystalline properties were characterized by optical polarizing microscopy, differential scanning calorimetry and X-ray diffraction. All the mesophases are identified as lamellar in structure.  相似文献   
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通过对由三个氘原子组成的氘团簇离子(d+3)与三个分立的氘核(3d+)在轰击吸氘固体靶时所发生的D-D聚变反应率的差别的研究,进而揭示氘团簇离子在与固体靶中的氘核发生聚变反应时所体现出的团簇效应.实验结果显示,在10—40keV/d能区,每个氘团簇中的氘核(d+3/3)所产生的聚变反应率高于具有相同速度的独立氘核(d+)所产生的聚变反应率.反之,在50—100keV/d能区,独立氘核比之于氘团簇中的单个氘核所产生的聚变反应率要高.两者之间的比值具有非常明显的能量相关性.这种团簇特性与团簇离子本身特性及固体靶环境等多方面因素有关.对其作用过程和实验中观测到的现象的实质做了具体讨论. 关键词:  相似文献   
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Let G be a connected, simply connected semisimple algebraic group over the complex number field, and let K be the fixed point subgroup of an involutive automorphism of G so that (G, K) is a symmetric pair. We take parabolic subgroups P of G and Q of K, respectively, and consider the product of partial flag varieties G/P and K/Q with diagonal K-action, which we call a double flag variety for a symmetric pair. It is said to be of finite type if there are only finitely many K-orbits on it. In this paper, we give a parametrization of K-orbits on G/P × K/Q in terms of quotient spaces of unipotent groups without assuming the finiteness of orbits. If one of P ? G or Q ? K is a Borel subgroup, the finiteness of orbits is closely related to spherical actions. In such cases, we give a complete classification of double flag varieties of finite type, namely, we obtain classifications of K-spherical flag varieties G/P and G-spherical homogeneous spaces G/Q.  相似文献   
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By using N-(3-triethoxysilyl)propylacrylamide (TPAAm), vinyl groups were introduced onto the surface of silica-gel. On the surface of this silica-gel, β-CyD was molecularly imprinted by using a redox initiator, and the composite was used as stationary phase of high performance liquid chromatography (HPLC). The pump pressure was sufficiently low and did not increase even after continuous elution for 24 h. In order to prepare still more stable columns, a new polymerization process was developed. There, the redox initiator was first mixed with the surface-modified silica-gel and then vinylated β-CyD, crosslinker, and the template were added. This modification promoted the immobilization of β-CyD copolymer to the silica-gel, resulting in still lower pump pressure. Concurrently, the imprinting efficiency was increased in comparison with previous method where the redox initiator was directly added to the mixture of the β-CyD–template complex, crosslinker, and surface-modified silica-gel. The molecularly imprinted β-CyD column, prepared by this new method, efficiently discriminated the enantiomers of N-benzyloxycarbonyltyrosine.  相似文献   
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The reorder-point-reorder-quantity policies referred to as (r,Q) policies are widely used in industry and extensively studiedin the inventory literature. It should be noted, however, thatshortages often occur in practice even when the optimal reorderpoint and reorder quantity are achieved. In this paper, we presenta mathematical model to control a shortage period by an emergencyorder. The problem is the determination of the best timing todeliver items after a shortage occurs. By applying the conceptof repair-limit replacement policy in the context of maintenancetheory, the optimal order time limits based on three kinds ofcost criteria are derived in the framework of a simple (r, Q)inventory system. Finally, some examples of the inventory controlmodel with a stochastic lead time are given to explain the optimalorder-limit policies.  相似文献   
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Objective: Postoperative complications and non-periprosthetic fractures (NPPFs), which was defined as a fracture existing non- periprosthetic implant, after total hip arthroplasty (THA) have a negative effect on the patients'' ability to perform activities of daily living. Thus, investigating these incidences of patients after THA will be valuable as it lead to a more strategic physical therapy interventions and advanced research to prevent these problems. The purpose of this study was to investigate the incidence of postoperative complications related to implants and NPPFs in patients after THA, a more than 10-year follow-up. Methods: This is a retrospective cohort study. A total 892 patients with hip osteoarthritis who underwent primary THA were analyzed (age at surgery was 45-79 years; 805 women; the average follow-up period was 12.4-year). The postoperative complications related to implants and NPPFs were calculated using data from their medical records. Results: The postoperative complications occurred in 37 patients, and NPPFs occurred in 72 patients, who were significantly older, and hip and knee OA diagnosis, compared to patients without NPPFs ( p <.05). The most common cause of NPPFs was minor trauma. In patients aged ≧ 65 years, significantly more NPPFs occurred during the first year after surgery( p <.05). Conclusion: More than 10-year after THA, the incidence of NPPFs was higher than that of postoperative complications related to implants. Older patients who had hip and knee OA were a significantly higher risk of developing NPPFs due to falls within the first year after surgery.  相似文献   
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Atomic and nuclear cluster effects of (D+3) were studied by alternative implantation of deuterium cluster ion beam and isolated deuteron (D+) beam on metal targets. The beam energy was adjusted from 10keV/d to 100keV/d in experiment. The atomic cluster effect was shown by the enhancement of X-ray emission induced by cluster deuterion. The average ratio of X-ray intensity induced by each cluster deuteron to that induced by each isolated deuteron is about 2.6 in the experimental energy region. The nuclear cluster effect is shown by the difference of D-D fusion rates induced by two kinds of deuterons under the same experimental conditions. The ratio of the D-D fusion rates induced by the two kinds of deuterons is energy dependent.  相似文献   
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