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1.
塑料产品表面装饰新工艺--模内复膜   总被引:1,自引:0,他引:1  
龚玉宏 《塑料工业》2005,33(11):1-3
简要介绍了模内复膜工艺的分类、工艺特性对比、各类模内复膜工艺的工艺过程.同时讨论了模内复膜产品设计原则以及装饰膜的预成型工艺及其公差经验值.  相似文献   
2.
Studies on emissions of nitrous oxide (N2O) from agricultural soils mostly focus on fluxes between the soil and the atmosphere or are limited to the atmosphere in the topsoil. However, in soils with shallow water tables, significant N2O formation may occur closer to the groundwater. The aims of this study were (i) to determine the importance of subsoil N2O formation in a sandy soil; and (ii) to obtain a quantitative insight in the contribution of subsoil N2O to the overall losses of N2O to the environment. We applied 15N labeled fertilizer at a rate of 5.22 kg 15N ha−1; 50% as Ca(NO3)2 and 50% as NH4Cl, on a mesic typic Haplaquod seeded with potatoes (Solanum tuberosum L.), and traced soil N2O concentrations and fluxes over a one-year period. Throughout the year, total N2O and the amount of 15N recovered in soil N2O were highest in the subsoil, with a maximum concentration at 48 cm depth in mid-February of 19900 μl m−3 and 24 μg 15N m−3, respectively. The maximum concentration coincided with the highest water-filled pore space of 71%. The cumulative flux of N2O was 446 g N2O-N ha−1, the recovery of 15N in this flux was 0.06%. During the summer, maximum fluxes followed high soil N2O concentrations. During winter, no such relation was found. We concluded that the formation of N2O was the highest in the subsoil, largely controlled by water-filled pore space rather than NO3 concentration or temperature. Although high subsoil N2O concentrations did not lead to high surface fluxes of N2O in the winter, artificial draining may lead to high indirect N2O emissions through supersaturated drainage water.  相似文献   
3.
工业测量中经常需要从获取的光斑图像中提取光斑区域,计算光斑中心的坐标。针对光斑图像具有背景区域较暗且面积大,目标(光斑)区域较亮且面积小的特点,提出了一种适用于光斑图像的阈值分割方法,计算单个光斑中心坐标的重心法,以及采用连通区域标记和区域大小排序计算多个光斑中心坐标的方法。与其他阈值分割方法比较后的实验结果表明,所提出的方法可更好地分割光斑图像,与期望的人工选取的阈值最接近,计算得到的光斑中心坐标准确,且运行时间较短。  相似文献   
4.
A new nertral complex,^99mTcCl(4-MCDO)3MEB,((Bis[4-methyl-1,2-cyclohex-anedionedioximato(1-)-O]-[4-methyl-1,2-cyclohexanedione-dioximato(2-)-O] methyl-borato(2-)-N,N‘,N″,N‘‘‘,N‘‘‘‘0-chlorotechnetium,generally called BATO(Boronic acid adducts of technitium dioximes),has been synthesized and evaluated for potential use in myocardial perfusion imaging,It has intrinsic affinity for the blood clearance.The uptake of heart.lung and blood in mice at 2min separately are 1.12,2.48 and 6.66%ID.The complex formation is rapid,simple and highly yielded(≥93%).This process is easy to kit formation.  相似文献   
5.
In product design process, when dealing with technical problems or initiating a new design, R&D personnel would often turn to technical database to seek inspiration. The building of a database with such documents has not been systematically dealt with. In this paper, several issues on how to build up a product design database are investigated: input source, sampling scheme and quality control. A case study of building a database for robotic design is used to demonstrate the concept. It is an archive of more than 1500 relevant technical papers. A total of 16 graduates are employed as operators in the labeling process and subsequently the hypothesis tests are utilized to process the labeling results. To ensure this database quality, the labeling consistency of each operator and the understanding of each category are tested. With the use of statistical methods, this work proposes a feasible and practical way to create such a database for product design.  相似文献   
6.
This paper deals with compact label-based representations for trees. Consider an n-node undirected connected graph G with a predefined numbering on the ports of each node. The all-ports tree labeling ℒ all gives each node v of G a label containing the port numbers of all the tree edges incident to v. The upward tree labeling ℒ up labels each node v by the number of the port leading from v to its parent in the tree. Our measure of interest is the worst case and total length of the labels used by the scheme, denoted M up (T) and S up (T) for ℒ up and M all (T) and S all (T) for ℒ all . The problem studied in this paper is the following: Given a graph G and a predefined port labeling for it, with the ports of each node v numbered by 0,…,deg (v)−1, select a rooted spanning tree for G minimizing (one of) these measures. We show that the problem is polynomial for M up (T), S up (T) and S all (T) but NP-hard for M all (T) (even for 3-regular planar graphs). We show that for every graph G and port labeling there exists a spanning tree T for which S up (T)=O(nlog log n). We give a tight bound of O(n) in the cases of complete graphs with arbitrary labeling and arbitrary graphs with symmetric port labeling. We conclude by discussing some applications for our tree representation schemes. A preliminary version of this paper has appeared in the proceedings of the 7th International Workshop on Distributed Computing (IWDC), Kharagpur, India, December 27–30, 2005, as part of Cohen, R. et al.: Labeling schemes for tree representation. In: Proceedings of 7th International Workshop on Distributed Computing (IWDC), Lecture Notes of Computer Science, vol. 3741, pp. 13–24 (2005). R. Cohen supported by the Pacific Theaters Foundation. P. Fraigniaud and D. Ilcinkas supported by the project “PairAPair” of the ACI Masses de Données, the project “Fragile” of the ACI Sécurité et Informatique, and by the project “Grand Large” of INRIA. A. Korman supported in part by an Aly Kaufman fellowship. D. Peleg supported in part by a grant from the Israel Science Foundation.  相似文献   
7.
热熔贴标机的主要工艺流程包括送标和送瓶,要求转速快,定位精度高。本文介绍了采用B&R高性能的PCC和伺服驱动器构成控制系统,并利用其电子凸轮技术实现既定的控制效果,因而大大减少了机械设计和制造成本以及运行磨损量,提高了控制精度和使用寿命。  相似文献   
8.
Let F be a function on pairs of vertices. An F-labeling scheme is composed of a marker algorithm for labeling the vertices of a graph with short labels, coupled with a decoder algorithm allowing one to compute F(u, v) for any two vertices u and v directly from their labels. As applications for labeling schemes concern mainly large and dynamically changing networks, it is of interest to study distributed dynamic labeling schemes. This paper investigates labeling schemes for dynamic trees. We consider two dynamic tree models, namely, the leaf-dynamic tree model in which at each step a leaf can be added to or removed from the tree and the leaf-increasing tree model in which the only topological event that may occur is that a leaf joins the tree. A general method for constructing labeling schemes for dynamic trees (under the above mentioned dynamic tree models) was previously developed in Korman et al. (Theory Comput Syst 37:49–75, 2004). This method is based on extending an existing static tree labeling scheme to the dynamic setting. This approach fits many natural functions on trees, such as distance, separation level, ancestry relation, routing (in both the adversary and the designer port models), nearest common ancestor etc.. Their resulting dynamic schemes incur overheads (over the static scheme) on the label size and on the communication complexity. In particular, all their schemes yield a multiplicative overhead factor of Ω(log n) on the label sizes of the static schemes. Following (Korman et al., Theory Comput Syst 37:49–75, 2004), we develop a different general method for extending static labeling schemes to the dynamic tree settings. Our method fits the same class of tree functions. In contrast to the above paper, our trade-off is designed to minimize the label size, sometimes at the expense of communication. Informally, for any function k(n) and any static F-labeling scheme on trees, we present an F-labeling scheme on dynamic trees incurring multiplicative overhead factors (over the static scheme) of on the label size and on the amortized message complexity. In particular, by setting for any , we obtain dynamic labeling schemes with asymptotically optimal label sizes and sublinear amortized message complexity for the ancestry relation, the id-based and label-based nearest common ancestor relation and the routing function. Supported in part at the Technion by an Aly Kaufman fellowship.  相似文献   
9.
杨志  胡晓倩  李二秋 《核技术》2003,26(11):849-852
为了研究99Tcm标记的抗乳腺癌单抗6C6及嵌合抗体6C6CHI在动物体内的生物学分布及在荷瘤裸鼠肿瘤中的摄取情况,采用改进的Schwartz法进行99Tcm标记抗体。标记后的抗体由小鼠尾静脉注射,观察不同时间的小鼠血液清除、全身清除以及两种99Tcm标记的抗体在荷人乳腺癌MCF7细胞的裸鼠中肿瘤的摄取情况,并在γ相机下于注射后不同时间显像。结果表明,99Tcm标记两种抗体的标记率均大于90%,标记抗体的免疫活性大于80%。99Tcm-6C6的全身清除半衰期为4.1 h,在血液中的半衰期分别为Tα=0.55 h、Tβ=12.42 h;99Tcm-6C6CHI的全身清除半衰期为4.28h,在血液中半衰期分别为Tα=0.98h、Tβ=12.42h。在荷人乳腺癌裸鼠中的体内分布结果是:在注射99Tcm-6C6后23h肿瘤和血的%ID·g-1分别为7.42±0.85和5.67±1.44。除肾外,T/NT(肿瘤/非肿瘤)比值均大于1。在注射99Tcm-6C6CHI后23h肿瘤和血的%ID·g-1分别为4.23±0.64和6.97±0.23,除瘤/血、瘤/肾比值小于1外,其余组织的T/NT均大于1。荷瘤鼠γ显像结果显示:在注射标记抗体后24h,肿瘤显像清晰,除肾外其它脏器无异常浓聚。抗乳腺癌单抗6C6在肿瘤中有较好的特异性,而人源化抗体6C6-CHI的肿瘤摄取稍低于6C6抗体,且血中放射性比6C6抗体高,但肿瘤显像清晰,而其它脏器的T/NT比值大于1,  相似文献   
10.
67Ga-EDTMP was synthesized in a single step by adding 67GaCl3 to EDTMP solution. Dependences of the radiolabeling yield of 67Ga-EDTMP on EDTMP concentration, pH and reaction time were examined. Under the optimum conditions, the radiolabeling yield of 67Ga-EDTMP was more than 97%. A biodistribution experiment in mice showed that 67Ga-EDTMP was mainly absorbed by skeleton and reached 13.25% at 0.5 h after injecting, then kept a high level in 72 h with a maximum value of 16.82% at 48 h. The results suggest that 67Ga-EDTMP might be a potential bone pain palliation radiopharmaceutical due to its high skeletal uptake, rapid blood clearance and relatively low soft-tissue absorption. But further work must be done to determine whether 67Ga-EDTMP is useful in the treatment of painful osseous metastases.  相似文献   
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