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101.
张云 《内燃机》2005,(2):50-50,58
结合实例,介绍了夹具设计的经验,特别就提高孔位置精度的问题进行了探讨。  相似文献   
102.
Within public health discourse there is growing recognition that the social structures and ecology of neighbourhoods impact on health and wellbeing. A clearer understanding of the pathways through which this influence occurs will inform locality-based interventions to tackle inequalities. In this paper we report on an interview based study with parents of young children living in Massey, a suburban neighbourhood of metropolitan Auckland. Locational access to community resources is comparatively poor in Massey as measured by a community resource accessibility index. The findings provide insights into the impact of such access to services and amenities on neighbourhood social cohesion. We conclude by suggesting planning strategies for strengthening neighbourhood identification and attachment for this population group.  相似文献   
103.
This study examined the associations among mothers' insightfulness into their infants' internal experience, mothers' sensitivity to their infants' signals, and infants' security of attachment to their mothers. The insightfulness of 129 mothers of 12-month-old infants was assessed by showing mothers 3 videotaped segments of observations of their infants and themselves and interviewing them regarding their infants' and their own thoughts and feelings. Interviews were classified into 1 insightful and 3 noninsightful categories. Mothers' sensitivity was assessed during play sessions at home and at the laboratory, and infant-mother attachment was assessed with the Strange Situation. Mothers classified as positively insightful were rated as more sensitive and were more likely to have securely attached children than were mothers not classified as positively insightful. Insightfulness also accounted for variance in attachment beyond the variance explained by maternal sensitivity. These findings add an important dimension to research on caregiving, suggesting that mothers' seeking of explanations for the motives underlying their infants' behavior is related to both maternal sensitivity and infant attachment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
文中就如何增大耦合效率和工艺容差的问题作了具体的分析,在此基础上,评述了现 有的几种能够获得较低插入损耗的光纤和波导的固定联接技术。  相似文献   
105.
For some applications, e.g. processes with stoichiometric reactions or the mixing of powders in a static mixer, a high short-term dosing constancy is necessary. For the dosing of calcium carbonate with a median diameter of 2 μm, it is shown that the pulsation of a volumetric feeder can be reduced tremendously by the use of different attachments for the dosing tube. The best results were obtained with a self-developed rotating star attachment. The quantitative assessment of the efficiency was performed both in the time domain with the standard deviation and in the frequency domain with the fast Fourier transformation.  相似文献   
106.
Replies to comments by 7 authors (see records 2001-18772-008, 2001-18772-009, 2001-18772-010, 2001-18772-011, and 2001-18772-012) in reference to the F. Rothbaum et al's original article (see record 2000-02781-001), which highlighted evidence of cultural variations in, and noted ways in which attachment theory is laden with Western values and meaning in comparisons of the US and Japan. Here, Rothbaum et al defend their central thesis and note areas of their agreement and disagreement with the aforementioned comments and criticisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
This work represents one stage in the optimization of biological nitrification by attached culture.The utilization of columns packed with fine granular media, such as Biolite, and sterile conditions has enabled the overall nitrite oxidation rates of the pure strain Nitrobacter winogradskyi serotype agilis in attached culture to be measured.The utilization of methods for counting attached bacteria, combined with measurements of the oxygen consumption, has enabled the specific respiratory activity of Nitrobacter in attached culture to be determined and a comparison to be made with the values observed with free cultures.The results obtained show a great increase in the nitrite oxidation rate and a 130% increase in the respiratory activities specific to attached bacteria in comparison with free cells.  相似文献   
108.
The interactions of the 936-species phages sk1, jj50, and 64 with the cell surface of Lactococcus lactis LM0230 were analyzed. Cell envelopes (walls + plasma membrane), cell wall, or plasma membrane from L. lactis ssp. lactis LM0230 each inactivated the phages in vitro. However, other 936-species phages kh and P008, which do not infect strain LM0230, were not inactivated by any of the subcellular fractions. Treating cell walls or plasma membrane with the cell wall hydrolase mutanolysin eliminated inactivation of phage sk1. This suggested that intact cell wall fragments were required for inactivation. A role for plasma membrane in phage sk1 inactivation was further investigated. Boiling, washing in 2 M KCl, 8 M urea, or 0.1 M Na(2)CO(3)/pH 11, or treating the plasma membrane with proteases did not reduce adsorption or inactivation of phage. Adding lipoteichoic acid or antibodies to lipoteichoic acid did not reduce inactivation of phage in a mixture with membrane, suggesting that lipoteichoic acid was not involved. Inactivation by envelopes or cell wall correlated with ejection of DNA from the phage sk1 capsid. Although calcium is required for plaque formation, it was not required for adsorption, inactivation, or ejection of phage DNA by envelopes or cell wall. The results suggest that at least for phages sk1, jj50, and 64, adsorption and phage DNA injection into the host does not require a host membrane protein or lipoteichoic acid, and that cell wall components are sufficient for these initial steps of phage infection.  相似文献   
109.
媒体结合单元(MAU)是现场总线仪表中的重要部件。介绍一种新型的媒体结合单元电路器件SIM1-2,该器件符合IEC61158-2数据链路层协议规范。在详细分析该器件的系统结构和主要功能的基础上,介绍其在总线仪表系统中的应用。并从资源需要,处理速度和功耗等方面分析单片机、通讯控制器、MAU电路的选择等关键问题。  相似文献   
110.
醇解法合成锥形氧化锌纳米粉体   总被引:1,自引:0,他引:1  
采用非水解法予150℃在乙二醇溶漳中合成了氧化锌粉体,用X射线衍射、透射电子显微镜和Fourier红外光谱对其进行了表征.结果表明:在乙二醇溶液中,可在较低的温度(150℃)制备出锥形纳米氧化锌粉体.所合成的纳米氧化锌以取向黏附的方式沿(002)方向进行择向生长,并呈现出强烈的紫外发射现象.  相似文献   
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