无油润滑压缩机活塞环和支承环设计

通过对填充聚四氟乙烯材料活塞环及带卸荷槽结构支承环的研究 ,确定了活塞及活塞环结构 ,建立了带卸荷槽支承环的力学分析模型 ,并将其结果用于结构尺寸的确定。在压缩机工艺指标不变的情况下 ,用该方法设计的活塞环和支承环性能优良。     

用添加剂改善柴油的颜色稳定性

利用实验室筛选出的一种柴油安定性改进剂改善柴油的颜色稳定性。贮存实验表明：成品柴油(催化裂化柴油组分占30％)中加入该剂300～400μg/g，可改善比色0．5-1．5个号，同时可抑制柴油氧化沉渣的生成，改善柴油的氧化安定性和颜色稳定性。     

HDPE装置超负荷低能耗生产方案的设计与实施

本文介绍大庆ＨＤＰＥ装置提高生产能力及产品质量的方法。通过采用釜外络合催化剂新技术和提浆液浓度可将ＨＤＰＥ装置聚合釜单釜的生产能力由４．７５ｔ／ｈ提高到５．０ｔ／ｈ，各项能耗下降，收到了增产降耗的显著效果，并使产品质量，产量，品种，能耗，物耗，环保６项指标全部达到了设计要求。     

灌洋桩加砼内撑挡土结构性状分析

本文以浙江东方股份有限公司营业楼工程为例，重点介绍了钻孔灌注桩加砼内撑型挡土结构的设计要点，并对这种结构的受力变形进行了研究。最后结合工程实测资料提出了几个对类似工程有参考意义的结论。     

狂PK的狂想曲

时隔前一次写“稀饭第九页”已经半年多了,我搬到了离单位较近的地方,已经不用像上次写的那样将刷牙和早饭这两项工作同时进行了,上班只要步行10分钟(假想图:需要坐3小时公车才能到单位的柳絮飞作崇拜状)。时间充裕了许多后,让我能有时间考虑许多问题,比如理想。以前我曾有很多     

活塞裙部润滑分析(上)

<正> 1 前言长期以来,活塞组件一直被认为是发动机机械摩擦损失的主要来源,而且又是表示其可靠性和耐久性的要害润滑界面。目前,已有几种试验方法,用于研究实际工作中的发动机活塞组件的摩擦情况。但是,目前还不可能在这些试验中分离出裙部的摩擦情     

Training for an agricultural discrimination task

Skeleton weed, centaurea juncea, is a declared weed in Western Australia because it competes with grain crops for nutrients and moisture. When it is found during harvesting, mechanised teams search and eradicate it. In an earlier report of field trials (Hartley et al, 1989) it was reported that search teams' detection rate was poor and since search teams had usually never seen skeleton weeds, visual discrimination learning was to be expected and observed during searches. The present study investigated the nature of this discrimination learning in a laboratory by developing a training programme of colour photographic slides of weeds in stubble. Subjects receiving specific training with feedback on their performance compared with those receiving pseudo-training showed a significant improvement in detections. Subsequently the benefit of the programme was validated in a field trial.     

Ergonomics in sickle operation

Sickle operation in harvesting has been analysed with reference to design features of nine different types of sickles, and field and laboratory based investigations on biomechanical stresses and physiological valuation on six farmers. It has been indicated that the blade geometry contributes significantly to human performance and there is ample scope for further design optimisation. The suggested modifications are: (i) sickle weight - 200 g; (ii) total length of sickle - 33 cm; (iii) handle length - 11 cm; (iv) handle diameter - 3 c cm; (v) radius of blade curvature - 15 cm; (vi) blade concavity - 5 cm; (vii) serrated sickle: tooth pitch - 0.20 cm and tooth angle - 60 degrees; (viii) ratio of the length of cutting surface to chord length - 1.20.     

A scalable, self-analyzing digital locking system for use on quantum optics experiments

Digital control of optics experiments has many advantages over analog control systems, specifically in terms of the scalability, cost, flexibility, and the integration of system information into one location. We present a digital control system, freely available for download online, specifically designed for quantum optics experiments that allows for automatic and sequential re-locking of optical components. We show how the inbuilt locking analysis tools, including a white-noise network analyzer, can be used to help optimize individual locks, and verify the long term stability of the digital system. Finally, we present an example of the benefits of digital locking for quantum optics by applying the code to a specific experiment used to characterize optical Schr?dinger cat states.     

公伯峡水电站压力钢管边坡预应力锚索施工

较为详细的介绍了黄河上游公伯峡水电站厂房压力钢管边坡1 000 kN、有粘结预应力锚索的施工经验,对类似地质情况下进行深孔预应力锚索施工有一定的参考价值。