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991.
单点系泊产品是海洋石油开发工程中的关键设备,介绍了作为其主结构的软管平台制作工艺方法,以及为保证产品的质量要求采取的方案及措施。  相似文献   
992.
Medication adherence—taking medication as prescribed—is critical for successful self-care, especially among older adults. Adherence depends on developing and implementing plans for taking medications. Age-related cognitive declines that affect adherence may be mitigated using external tools that support patient-provider collaboration needed to develop these adherence plans. We tested the effectiveness of structured collaborative medication tools to support better medication planning and adherence practices. Evidence for benefits of collaborative tools has been mixed in terms of their usefulness for medication-scheduling tasks, perhaps because the tools have not been explicitly designed to support patient-provider collaboration. A total of 144 community-dwelling older adults participated in pairs and performed the role of a patient or provider in a simulated patient-provider medication-scheduling task. Each pair worked with a structured (MedTable? and e-MedTable) or unstructured (Medcard) scheduling tool and completed four problems (2 simple and 2 complex). Performance was measured using the following: problem-solving (medication schedule) accuracy, problem-solving time, solution (schedule) optimality, tool usability, collaborative effectiveness, and subjective workload involved in creating the medication schedules. Participants using structured tools produced more accurate and optimal schedules. They also rated subjective workload as lower and thought that the structured tools were easier to use, reduced subjective workload associated with creating the schedules. There was also suggestive evidence that participants using the structured tools rated more highly the quality of their collaboration. Structured medication-scheduling tools have the potential to improve medication adherence among older adults because they support collaborative planning and reduce the cognitive load involved in creating these adherence plans.  相似文献   
993.

Abstract  

In this study, an easily synthesized polydentate ligand N,N,N’,N’-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine (1) in combination with [Pd(C3H5)Cl]2 was found to be an active catalyst in copper-free Sonogashira reactions. Most substrates, including steric hindered phenyl bromides and heteroaryl bromides, could couple efficiently with terminal alkynes in the presence of low catalyst loading (0.1 mol%) and this catalytic system showed excellent functional group tolerance. The influence of water in this system was also preliminarily investigated via 31P NMR in situ; that is, appropriate water favors the reaction while excess hindered this reaction.  相似文献   
994.
Soil Mechanics and Foundation Engineering - The softening and degradation effects of water on soil mass, increase of pore water pressure, and reduction of matric suction are usually considered for...  相似文献   
995.
Schottky junction and p-n heterojunction are widely employed to enhance the charge transfer during the photocatalysis process. Herein, Cu and Cu3P co-modified TiO2 nanosheet hybrid (Cu–Cu3P/TiO2) was fabricated using an in situ hydrothermal method. The ternary composite achieved the superior H2 evolution rate of 6915.7 μmol g?1 h?1 under simulated sunlight, which was higher than that of Cu/TiO2 (4643.4 μmol g?1 h?1) and Cu3P/TiO2 (6315.8 μmol g?1 h?1) and pure TiO2 (415.7 μmol g?1 h?1). The enhanced activity can be attributed to the collaboration effect of Schottky junction and p-n heterojunction among Cu/TiO2 and Cu3P/TiO2, which can harvest the visible light, reduce the recombination of charge carriers and lower the overpotential of H2 evolution, leading to a fast H2 evolution kinetics. This work develops a feasible method for the exploration of H2 evolution photocatalyst with outstanding charge separation properties.  相似文献   
996.
This Article presents a three dimensional numerical model investigating thermal performance and hydrodynamics features of the confined slot jet impingement using slurry of Nano Encapsulated Phase Change Material (NEPCM) as a coolant. The slurry is composed of water as a base fluid and n-octadecane NEPCM particles with mean diameter of 100nm suspended in it. A single phase fluid approach is employed to model the NEPCM slurry.The thermo physical properties of the NEPCM slurry are computed using modern approaches being proposed recently and governing equations are solved with a commercial Finite Volume based code. The effects of jet Reynolds number varying from 100 to 600 and particle volume fraction ranging from 0% to 28% are considered. The computed results are validated by comparing Nusselt number values at stagnation point with the previously published results with water as working fluid. It was found that adding NEPCM to the base fluid results with considerable amount of heat transfer enhancement.The highest values of heat transfer coefficients are observed at H/W=4 and Cm=0.28. However, due to the higher viscosity of slurry compared with the base fluid, the slurry can produce drastic increase in pressure drop of the system that increases with NEPCM particle loading and jet Reynolds number.  相似文献   
997.
998.
多媒体信息呈几何级数的爆炸性增长,带来海量信息的同时也带来庞大的数据量,加重了网络的负担,同时不同用户对所要接收图像的质量要求有所不同,如果以相同的标准进行处理势必会造成一定程度上信息的浪费。文章对静止图像的渐进编码作了进一步的研究,对基本层和增强层采用不同的编码策略,更加适应网络复杂多变的带宽条件。文章还通过与用户之间的交互式操作来满足用户不同的需求。实验结果表明,在压缩效果达到JPEG压缩标准的情况下,增强了渐进功能,更加适应网络需要。  相似文献   
999.
Quantum Information Processing - Physical constraints make it challenging to implement and control many-body interactions. For this reason, designing quantum information processes with Hamiltonians...  相似文献   
1000.
随着国内家政行业进阶为万亿级市场,家政业务交易额每年增幅都超过20%.家政O2O作为大众期望的一种运营模式,刚好能迎合这样快速发展的家政市场.首先介绍了国内家政服务市场的现状,然后分析了家政O2O的发展基础,最后以95081的家政O2O模式为例,分析了国内家政O2O的出路.  相似文献   
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