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1.
正环肥燕瘦皆是美,家具产品也是如此。那些搭配了厚厚的软垫、或大量采用棉绒等物料填充的沙发和休闲椅,大都属于"环肥"这一类型,身体软软的,看起来稍显丰满,但同时也拥有舒适柔软的触感与就坐体验,带着些温柔的暖意,有着一种柔和之美。而也有一些家具产品,它们多以木材和金属为主要材料,利用材质本身的特质大胆地呈现出线条与骨架,并使其成为设计的亮点,给人以一种"瘦"的小骨感之美。本期将和各位读者分享一些富有小骨感美的家具产品,他们给人的感觉是干净爽落的,或是木质,保留了木材本来的颜色,不给  相似文献   
2.
正白岩松说,没事儿的时候发发呆。我们疲于追逐成功的路上,发呆成了一种奢侈。是啊,回想一下,在我们每天仅有的24小时中,工作、交际以及各种琐事占据了大半,剩下的注意力又被手机等携带大量娱乐信息的产品夺走。我们每天生活的似乎都很"丰满",迈着急促的脚步穿梭于公司、学校、商场、电影院之间,甚至感觉时间不够用,经常熬夜到凌晨,因此,我们没有多余的时间去发呆,或者说,在这个充满娱乐信息的时代,我们不需要去孤独地发呆。  相似文献   
3.
对不同配合比混凝土试件在海洋水下区进行现场暴露试验,通过实验室内对混凝土中硫酸根离子含量测定,研究腐蚀龄期、水胶比及矿物掺合料对混凝土抗硫酸盐侵蚀的影响,探究硫酸盐在混凝土内部侵蚀机理。试验结果表明:侵蚀到混凝土试件内部的自由硫酸根离子含量与总硫酸根离子含量,随着侵蚀龄期和水胶比的不同而变化,同时向混凝土中掺入一定比例的粉煤灰、矿粉等矿物掺合料可以改善混凝土试件内部孔隙结构,有效提高其抗硫酸盐侵蚀能力,从而延长混凝土结构耐久性能。  相似文献   
4.
This report provides a review of early and late effects of radiation in normal tissues and organs with respect to radiation protection. It was instigated following a recommendation in Publication 103 (ICRP, 2007), and it provides updated estimates of 'practical' threshold doses for tissue injury defined at the level of 1% incidence. Estimates are given for morbidity and mortality endpoints in all organ systems following acute, fractionated, or chronic exposure. The organ systems comprise the haematopoietic, immune, reproductive, circulatory, respiratory, musculoskeletal, endocrine, and nervous systems; the digestive and urinary tracts; the skin; and the eye. Particular attention is paid to circulatory disease and cataracts because of recent evidence of higher incidences of injury than expected after lower doses; hence, threshold doses appear to be lower than previously considered. This is largely because of the increasing incidences with increasing times after exposure. In the context of protection, it is the threshold doses for very long follow-up times that are the most relevant for workers and the public; for example, the atomic bomb survivors with 40-50years of follow-up. Radiotherapy data generally apply for shorter follow-up times because of competing causes of death in cancer patients, and hence the risks of radiation-induced circulatory disease at those earlier times are lower. A variety of biological response modifiers have been used to help reduce late reactions in many tissues. These include antioxidants, radical scavengers, inhibitors of apoptosis, anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, growth factors, and cytokines. In many cases, these give dose modification factors of 1.1-1.2, and in a few cases 1.5-2, indicating the potential for increasing threshold doses in known exposure cases. In contrast, there are agents that enhance radiation responses, notably other cytotoxic agents such as antimetabolites, alkylating agents, anti-angiogenic drugs, and antibiotics, as well as genetic and comorbidity factors. Most tissues show a sparing effect of dose fractionation, so that total doses for a given endpoint are higher if the dose is fractionated rather than when given as a single dose. However, for reactions manifesting very late after low total doses, particularly for cataracts and circulatory disease, it appears that the rate of dose delivery does not modify the low incidence. This implies that the injury in these cases and at these low dose levels is caused by single-hit irreparable-type events. For these two tissues, a threshold dose of 0.5Gy is proposed herein for practical purposes, irrespective of the rate of dose delivery, and future studies may elucidate this judgement further.  相似文献   
5.
We propose a new Geographic Information System (GIS) three-dimensional (3D) data model based on conformal geometric algebra (CGA). In this approach, geographic objects of different dimensions are mapped to the corresponding basic elements (blades) in Clifford algebra, and the expressions of multi-dimensional objects are unified without losing their geometric meaning. Geometric and topologic computations are also processed in a clear and coordinates-free way. Under the CGA framework, basic geometrics are con...  相似文献   
6.
The electric contact material of Ag/SnO2 composite was achieved by reactive synthesis method. The compositions and microstructure of Ag/SnO2 composite were analyzed and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution electron microscopy (HRTEM). The structural feature was typical of the particle reinforced composites. The HRTEM images revealed that the observed Ag/SnO2 interface was absence of the precipitated phase and the lattice contrast across the interf...  相似文献   
7.
Zr 55 Al 10 Cu 30 Ni 5 bulk metallic glass was rolled up to 95% in thickness reduction at room temperature, and the dependences of microstructure and thermal stability on the strain were investigated. It is revealed that phase transformations do not occur during the rolling, but the split of the crystallization peaks becomes more and more obvious with increasing thickness reduction. Analyses of the radial distribution functions and the pair correlation functions indicate that the rolling has enhanced the sh...  相似文献   
8.
An instrumented drilling system can be applied for the acquisition of drilling process parameters.The system can provide continuous and huge data for geotechnical engineering.However, due to the complexity of ground strata, the variation in the drilling parameters with stratigraphical characteristics is great and the correlation between likely comparable parameters is not high, which limits the use of conventional correlation approaches in this field.How to use the data for engineering and how to get a reasonable interpretation for the relationships among the drilling parameters, as well as between a drilling parameter and formational character-istics, become a technical choke point for the development and application of the instrumented drilling system.Based on similarity criteria, the extraction of sample data and characteristics, the pretreatment of data and feature matching algorithms have been ana-lyzed and an approach of slope coefficient searching identification has been established.A case study was carried out for the similar-ity between the rotational speed of the drill bit, flushing pressure, and effective thrust force graphics in general weathered granite.The result shows that the similarity coefficients between the rotational speed of the drill bit, flushing pressure, and effective thrust force are 0.72 and 0.83, respectively.Although there are differences between the distances of the graphics, the curves of both rota- tional speed and flushing pressure agree with the effective thrust curve in shape, which provides a possible method for the identifica- tion of various formations by use of the similarity between feature drilling parameters.  相似文献   
9.
A Ti+Nb bearing ultra-low carbon bake hardening sheet steel hot-rolled in the conventional austenite region and in the ferrite region with lubrication was experimentally studied.Subsequent cold rolling and continuous annealing processes were also conducted.The results show that microstructures of ultra-low carbon bake hardening hot strips at room temperature are basically irregular polygonal ferrites.The yield strength,ultimate tensile strength,n value,and r value of the No.2 specimen hot-rolled in the ferr...  相似文献   
10.
A SiC whisker-toughened MoSi2-SiC-Si coating was prepared on carbon/carbon (C/C) composites surface by a two-step technique of slurry and pack cementation, and the effects of thermal shock and oxidation on the mechanical property of the coated C/C were studied. The flexural strength of C/C composites was improved by 6.8% after coated by SiC whisker-toughened MoSi2-SiC-Si. After thermal cycle between 1773 K and room temperature in air for 10 times, the mass loss of the coated sample was 5.08% and the percent...  相似文献   
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