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991.
滩海油田人工岛特殊的海况和工况条件,对岛内的油气生产作业提出了全新的安全和环保理念。为此探讨和实践新领域内的试油安全环保管理模式,能够最大限度地保障人工岛试油期间的安全环保控制,实现试油与全岛各类油气生产作业的有序整体融合。  相似文献   
992.
《河北冶金》作为河北省冶金行业唯一的国内外公开发行的科技期刊,创刊于1979年11月,伴随着我国的改革开放走过了33年的历程,在改革中诞生,在改革中成长。33年中,《河北冶金》承载着河北冶金行业科技工作者的厚望,历经磨难,奋力拼搏,以其高质量、有特色赢得了广泛赞誉,成为今天在国内外期刊界有一定影响力的科技刊物,以其独有的专业特色和综合性内容展现出自己的风采,标识出存在的价值,屹立于中国科技期刊之林。  相似文献   
993.
This study focused on the mechanical behavior of reinforced lightweight aggregate concrete (RLAC) walls under repeated horizontal loads after a standard temperature‐rising fire‐resistance test and compared the specimen walls' ultimate loads, yielding loads, cracked loads, stiffness, and ductility with those of reinforced normal‐weight aggregate concrete (RNAC) walls. Steel reinforcing bar spacing, aggregate types, wall widths, and high temperatures were variables in this study. The experimental results showed that, after the fire‐resistance test, the smaller the steel reinforcing bar spacing of RLAC walls, the higher the yield and ultimate loads, yet the worse the ductility and the hysteresis loop's energy, whereas the greater the width of the wall, the greater the stiffness and the higher the hysteresis loop's energy. The differences in terms of stiffness, ductility, and hysteresis between RLAC walls with and without the fire‐resistance test were insignificant, indicating that RLAC walls do not lose their basic mechanical behavior during a high‐temperature fire. RNAC walls showed, indeed, a significant downward trend for strength and hysteresis after the fire‐resistance test, but the decrease was much less clear for stiffness. Therefore, RLAC walls did show better seismic resistance than RNAC walls under the same testing conditions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
994.
以紫木凼金矿为工程背景,介绍了井田进路全面采矿法试验过程,试验取得了矿块生产能力79t/d、采矿损失率7.8%、矿石贫化率11.7%较好的技术经济指标,不仅达到了设计指标,还为工业生产推广应用打下了基础。  相似文献   
995.
Purpose: To enhance the transdermal delivery of diclofenac acid (DA) by using O-acylmenthol as a penetration enhancer and complexing with amines, or by a combination of the two methods. Methods: The skin permeability of diclofenac was tested in vitro across rat skin with each of the evaluated permeants in a saturated isopropyl myristate (IPM) donor solution. Results: A 4.5-fold increase in the flux of diclofenac was observed by ion-pair formation with diethylamine; however, the cations with hydroxyl groups had negative effects on the transdermal delivery of diclofenac. 2-isopropyl-5-methylcyclohexyl 2-hydroxypanoate and 2-isopropyl-5-methylcyclohexyl heptanoate produced significant increase in the permeation of diclofenac potassium (D-K); however, both of them were ineffective for the other diclofenac salts, including diclofenac diethylamine (D-DETA), diclofenac ethanolamine (D-EA), diclofenac diethanolamine (D-DEA), diclofenac triethanolamine, and diclofenac N-(hydroxylethyl) piperidine. 2-isopropyl-5-methylcyclohexyl tetradecanoate was effective on the penetration of D-K, D-DETA, D-EA, and D-DEA. Also, it is exciting to note that the combined use of diethylamine with 2-isopropyl-5-methylcyclohexyl tetradecanoate produced a 9.74-fold increase in accumulation amount of diclofenac compared with DA in IPM. Conclusions: The use of ion pair in combination with O-acylmenthol is necessary to further increase the diclofenac flux to provide better compliance for the patients undergoing clinical therapy.  相似文献   
996.
First-principles method was performed to predict the effect of Ti addition on thickness and adhesion of 55 pct Al-Zn-1.6 pct Si coating. The results of optimized geometric configurations, total energy, and charge distributions for the Ti substitution in Fe2Al5 and FeAl3 phases indicated Ti will grab electronic charges from Al atoms, form bonds with neighboring Al, which will reduce the growth of Fe-Al intermetallic layers, and finally enhance the adhesion of the coating/substrate. Furthermore, experiments were performed to validate the prediction results of first-principles successfully.  相似文献   
997.
研究了不同改性水平的γ-聚谷氨酸(以下简写为γ-PGA)吸附去除水体中重金属离子Pb2+的性能影响。研究结果表明,交联改性后的γ-PGA与未改性的γ-PGA相比,具有更好的Pb2+吸附性能,在将改性γ-PGA加入到含有Pb2+的水体中并均匀混合之后,随着交联度的提高,改性γ-PGA吸附Pb2+的性能逐渐增加,但在吸附最终结束时,不同改性的γ-PGA对Pb2+吸附去除率均在99%以上。在吸附去除Pb2+影响因素分析中发现Pb2+初始质量浓度和溶液pH对不同改性的γ-PGA吸附去除Pb2+性能的影响较大。随着Pb2+质量浓度的增加,不同改性水平γ-PGA对Pb2+的去除率均略有一定程度的下降。当溶液的pH控制在中性或者偏碱性时,25%改性γ-PGA对Pb2+的去除率能够保持在99%以上,当pH降至4.5和3时,Pb2+去除率分别降为90.76%和78.46%。  相似文献   
998.
Abstract

Pb1‐x Sn x Te epitaxial layers were successfully grown on PbTe substrates by liquid phase epitaxy (LPE) technique. The compositions and surface morphology of the epitaxial Pb1‐x Sn x Te layers were controlled in the LPE growth, and p‐Pb1‐x Sn x Te/n‐PbTe heterodiodes with a good junction‐perfection factor were made.  相似文献   
999.
建筑外延     
卜冰 《时代建筑》2014,(1):26-27
文章将建筑师从事建筑学领域以外的活动分类梳理为四个方向——生活体验、艺术创作、空间运营、媒体传播,发现外延活动的共性所在,并期待其对建筑学本身的影响可以成为值得研究的课题。  相似文献   
1000.

Cloud databases provide facilities for large scale data storage and retrieval of distributed data. However, the current access control techniques provided in database systems for maintaining security are not sufficient to secure the private data stored in public cloud databases. In this paper, a new secured data storage algorithm for effective maintenance of confidential data is proposed. To perform storage and retrieval operations of data in the cloud data storage effectively, map reduce algorithms are developed in this work which performs data reduction and fast processing. In order to consider the temporal nature of documents to be retrieved, we propose a new algorithm called Temporal Secured Cloud Map Reduced Algorithm which integrates temporal constraints with map reduce algorithms and also the chaining Hill Cipher encryption algorithms which is proposed newly in this work. The main advantages of the proposed algorithm is that they reduce the processing time and maintains security effectively. The experimental results obtained from this work depict that the proposed model is optimizing cost and it ensures data security.

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