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81.
孙克  张春华 《农药》1996,35(8):28-29
本文采用气相色谱法分析乳氟禾草灵的含量,选用OV-17固定液,Gas-ChromQ为担体制备色谱柱,以苯二甲酸二正戊酯为内标物。方法的标准偏差为0.31,变异系数为0.34%,乳氟禾草灵的回收率在99.21-100.70%之间。  相似文献   
82.
Ke Chen 《Ergonomics》2014,57(5):635-652
The purpose of this study was to develop and test a senior technology acceptance model (STAM) aimed at understanding the acceptance of gerontechnology by older Hong Kong Chinese people. The proposed STAM extended previous technology acceptance models and theories by adding age-related health and ability characteristics of older people. The proposed STAM was empirically tested using a cross-sectional questionnaire survey with a sample of 1012 seniors aged 55 and over in Hong Kong. The result showed that STAM was strongly supported and could explain 68% of the variance in the use of gerontechnology. For older Hong Kong Chinese, individual attributes, which include age, gender, education, gerontechnology self-efficacy and anxiety, and health and ability characteristics, as well as facilitating conditions explicitly and directly affected technology acceptance. These were better predictors of gerontechnology usage behaviour (UB) than the conventionally used attitudinal factors (usefulness and ease of use).

Practitioner Summary: Previous studies have not given much consideration to age-related health and associated abilities when examining acceptance of technology by the ageing population. By encompassing conventional technology acceptance constructs together with age-related health and ability characteristics, the present study was able to identify more factors affecting gerontechnology acceptance by older Hong Kong Chinese.  相似文献   

83.
本文针对三聚氰胺甲醛树脂合成与性能上存在的几个问题,从理论和实践上进行了讨论。  相似文献   
84.
Macroporous material of Sn-Cu alloy of different pore sizes designated as anode in lithium-ion batteries were fabricated through colloidal crystal template method. The structure and electrochemical properties of the macroporous Sn-Cu alloy electrodes were examined by using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and galvanostatic cycling. The results demonstrated that the electrodes of macroporous Sn-Cu alloy with pore size respectively of 180 and 500 nm can deliver reversible capacity of 350 and 270 mAh g−1 up to 70th cycles of charge/discharge. The cycle performance of the macroporous Sn-Cu alloy of 180 nm in pore size is better than that of the macroporous Sn-Cu alloy with 500-nm-diameter pores. It has revealed that the porous structure of the macroporous Sn-Cu alloy material is of importance to strengthen mechanically the electrode and to reduce significantly the effect of volume expansion during cycling.  相似文献   
85.
用化能自养的氧化铁硫杆菌和氧化硫硫杆菌,对河北半壁山含砷金精矿进行了公斤级的预处理氧化脱砷实验.在细菌预处理反应器中的连续和批式脱砷实验表明,目前选育的菌种是有效的.严格控制工艺条件,可以在4天左右便脱砷率高于80%.后续氰化提金实验证实,金的总回收率可达90%以上.用微生物脱砷预处理难冶含砷金矿有金浸出率高、便于固定浸出的砷、免除对环境污染的优点,是有很好应用前景的处理难冶含砷金矿的技术路线.  相似文献   
86.
87.
The cycling performance of a silicon/carbon composite anode has been significantly enhanced by using acrylic adhesive and modified acrylic adhesive as binder to fabricate the electrodes for lithium ion batteries. The capacity retentions of Si/C composite electrodes bound by acrylic adhesive and modified acrylic adhesive are 79% and 90% after 50 cycles, respectively. These two binders are electrochemically stable in the organic electrolyte in the working window. They also show larger adhesion strength between the coating and the Cu current collector as well as smaller solvent absorption in the electrolyte solvent than polyvinylidene fluoride (PVDF). Furthermore, sodium carboxyl methyl cellulose (CMC) plays an important role on improving the properties of acrylic adhesive, which increases the adhesive strength of acrylic adhesive and improves the activation of the electrodes.  相似文献   
88.
本研究采用SoL-GeL法和自动引燃法制备[(2Y-ZrO)-AlO]超微粉,并进行了微观结构分析。为比对223两种超微粉性能的差异,采用注浆成型法制备样品,并分别测定抗折强度,断裂韧性和烧结温度。结果表明:自动引燃制备的ZrO-AlO掺稀土纳米微粉,工艺简单、细小均匀,由其烧造的样品较SoL-GeL法样品抗弯强度高,223断裂韧性好,烧结温度低。  相似文献   
89.
聚丙烯耐熔垂性能的改进   总被引:1,自引:1,他引:1  
王珂  陈华来 《中国塑料》1996,10(3):18-21
本文了共聚、共混、填充等技术改进聚丙烯耐熔垂性能的规律,并对改性后聚丙烯的力学性能进行了研究。  相似文献   
90.
Ke Wang  Hong Yang  Qin Zhang  Qiang Fu  Zhenqiang Yu 《Polymer》2006,47(20):7103-7110
In this article, the injection-molded bars of isotactic polypropylene/organoclay nanocomposite with different clay contents have been obtained via dynamic packing injection molding (DPIM). The oriented microstructure including layered nanoparticles and PP lamellae has been inspected through 2D-WAXS analyses along the sample thickness of the molded bars. Depending on the clay content and sample thickness, various oriented clay structures with nanoparticles uniplanar-axially oriented parallel to the surface of molded bar, or partially tumbled around the flow axis of the molded bar, or even a random orientation, could be observed. The observed orientation behavior of nanoparticles could be temporarily elucidated as the results of the sensitive response of layered nanoparticles to shear deformation and the structural recovery of clay network assisted by the electrostatic attraction existing between adjacent nanoplatelets.  相似文献   
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