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101.
An organic–inorganic hybrid zinc phosphate with 28‐ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5‐tri(4‐pyridyl)‐imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two‐dimensional organic–inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis.  相似文献   
102.
A continuous flow reaction system was developed for the synthesis of 2,2,2-trichloroacetophenone derivatives. When aryl propiolic acids and water were mixed with trichloroisocyanuric acid in DMF at 5?°C, the 2,2,2-trichloroacetophenone derivatives were formed within 5?min with good yields. In addition, the resulting mixture was flowed to react with amines to give the corresponding benzamide. This flow reaction system provided higher yields within shorter times than the batch reaction system.  相似文献   
103.
Journal of Radioanalytical and Nuclear Chemistry - Radiation dose to personnel on the ground contaminated with radioactive cesium after nuclear power plant accident depends on cesium activity,...  相似文献   
104.
Brualdi et al. [Codes with a poset metric, Discrete Math. 147 (1995) 57-72] introduced the concept of poset codes, and gave an example of poset structure which admits the extended binary Golay code to be a 4-error-correcting perfect P-code. In this paper we classify all of the poset structures which admit the extended binary Golay code to be a 4-error-correcting perfect P-code, and show that there are no posets which admit the extended binary Golay code to be a 5-error-correcting perfect P-code.  相似文献   
105.
106.
Cellulose nanofibrils (CNFs) from hardwood bleached kraft pulp (HwBKP) are produced via enzymatic, chemical, and mechanical treatment. A nanoporous structured CNF-based separator is produced, and the electrochemical performance, morphology, and thermal stability analyses are performed in comparison to the commercial polyethylene separator. The results obtained show that the electrolyte-philic CNF separator has capacity retention of 88.6% over 200 cycles and very good ionic conductivity and wettability results due to its high hydrophilic nature. At 140°C, the CNF separator was resilient to heat and remained intact. The CNF separator reflects high thermal resistance and good electrolyte uptake properties that are among the mandatory requirements of a separator hence, a promising contender for use in lithium-ion batteries.  相似文献   
107.
Despite the importance of water photolysis in atmospheric chemistry, its mechanism is not well understood. Two different mechanisms for water photolysis have been proposed. The first mechanism is driven by water photoexcitation, followed by the reaction of the active hydrogen radical with water clusters. The second mechanism is governed by the ionization process. Both photoexcited and photoionized mechanisms are complementary, which is elucidated by using excited-state ab initio molecular dynamics simulations based on complete active space self-consistent field approach and unrestricted M?ller-Plesset second-order perturbation theory based Born-Oppenheimer molecular dynamics simulations.  相似文献   
108.
As a part of our ongoing search for a safe and efficient anti-tumor vaccine, we attempted to determine whether the molecular nature of certain tumor antigens would influence immune responses against tumor cells. As compared with freeze-thawed or formaldehyde-fixed tumor antigens, heat-denatured tumor antigens elicited profound anti-tumor immune responses and greatly inhibited the growth of live tumor cells. The heat-denatured tumor antigens induced a substantial increase in the anti-tumor CTL response in the absence of any adjuvant material. This response appears to be initiated by strong activation of the antigen-presenting cells, which may recognize heat-denatured protein antigens. Upon recognition of the heat-denatured tumor antigens, macrophages and dendritic cells were found to acutely upregulate the expression of co-stimulatory molecules such as B7.2, as well as the secretion of inflammatory cytokines such as IL-12 and TNF-alpha. The results of this study indicate that heat-denatured tumor extracts might elicit protective anti-tumor adaptive immune responses and also raise the possibility that a safe and efficient adjuvant-free tumor vaccine might be developed in conjunction with a dendritic cell-based tumor vaccine.  相似文献   
109.
We derive the Singleton bound for poset codes and define the MDS poset codes as linear codes which attain the Singleton bound. In this paper, we study the basic properties of MDS poset codes. First, we introduce the concept of I-perfect codes and describe the MDS poset codes in terms of I-perfect codes. Next, we study the weight distribution of an MDS poset code and show that the weight distribution of an MDS poset code is completely determined. Finally, we prove the duality theorem which states that a linear code C is an MDS -code if and only if is an MDS -code, where is the dual code of C and is the dual poset of   相似文献   
110.
Hong JW  Chung KH  Yoon HC 《The Analyst》2008,133(4):499-504
An application of a novel polymer microfluidic chip for sample exchange via natural capillary forces for immuno-analysis is described. The microfluidic device was designed to achieve sample replacement by capillary force only, which would therefore be suitable for point-of-care-testing. Complete and automatic replacement of the sample in the reaction chamber with another one makes the chip able to mimic affinity chromatography and immunoassay processes. The microfluidic chip was made using polymer replication techniques, which were suitable for fast and cheap fabrication. Micrometre-sized polystyrene beads were used for the functionalization of biomolecules. Dinitrophenyl (DNP) and anti-DNP antibody coordination was employed on the chip for fluorescence analysis. DNP was immobilized on the polymer beads via a pre-adsorbed dendrimer layer and the beads were placed in the reaction chamber. Fluorescein tagged anti-DNP was successfully observed by a fluorescence microscope after the completion of the entire flow sequence. A calibration curve was registered based on the anti-DNP concentration. A multiplex sensing was accomplished by adding biotin/streptavidin coordination to the system. DNP and biotin conjugated beads were placed in the reaction chamber in an ordered fashion and biospecific bindings of anti-DNP antibody and streptavidin were observed at their expected sites. A ratiometric analysis was carried out with different concentration ratios of anti-DNP/streptavidin. The microfluidic chip described in this work could be applied to various biological and chemical analyses using integrated washing steps or fluid replacement steps with minimum sample handling.  相似文献   
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