The maximum surgical blood order schedule and surgical blood use in the United States

The outdating of units of blood can be reduced by decreasing the amount of time they spend in an assigned or crossmatched status. This reduction can be achieved in a hospital by establishing a maximum surgical blood order schedule (MSBOS) which reduces the excessive number of units of blood crossmatched preoperatively for patients undergoing elective surgery. The various steps which occurred in the development of a MSBOS in a large general hospital are detailed and the projected reduction in the number of crossmatched units which can be achieved with the MSBOS is illustrated. illustrated. The projected number of units of blood transfused to patients during their hospitalization for 50 common primary surgical procedures in the United States during 1974 is presented as a basis for defining maximum blood orders for each procedure.     

An improved snare system for the nonsurgical retrieval of intravascular foreign bodies

We have modified a snare technique originally described for transcolonoscopic removal of colonic polyps for the retrieval of intravascular foreign bodies. The key difference from other snare techniques is the employment of a wire snare with a crimp in its midportion that enables the formation of a loop in a plane perpendicular to the axial direction of the guiding catheter. With this technique we have quickly removed a variety of objects from the right heart and pulmonary arteries in four patients.     

超细石墨插层化合物的制备及性能测试

以浓硫酸和重铬酸钾为强氧化剂,对2—5μm微粉石墨进行了浓硫酸和冰醋酸插层。通过控制反应物之间的比例,可制各出膨胀容积为7．6～13．6mL/g的超细石墨插层化合物。应用FTIR光谱仪和大气采样器研究了产物的红外消光能力和空中飘浮能力。结果表明,该产物与原石墨、市售可膨胀石墨相比有较大的空中飘浮能力及红外遮蔽能力。     

平顶山盐厂废弃盐泥的开发和利用工艺研究

针对平顶山盐厂在生产过程中所排放的废弃盐泥的特点 ,摸索出了一条利用废弃盐泥转化为工业级建筑石膏及石膏墙体砌体材料的生产工艺。此工艺小试成功 ,产品经权威部门检验 ,完全符合国家标准     

泥页岩水化对岩石力学强度的影响

泥页岩经过水溶液浸泡,会因水化作用而膨胀,造成抗压强度、黏聚力、岩石强度及井壁稳定性下降,进而引起井壁失稳问题。进行单轴抗压试验和单轴抗拉试验,在不同离子类型及浓度的水溶液条件下,研究泥页岩的弹性模量、泊松比、破裂时的最大载荷值以及部分岩心的抗拉强度的变化趋势。实验结果表明在相同的试验条件下,泥页岩水化程度与钻井液类型有关,氯化钾钻井液对泥页岩的抑制作用最好。     

瓦斯抽采钻孔漏气通道检测装置研制及应用

瓦斯抽采钻孔孔周裂隙和封孔段空隙通道是造成钻孔漏气失效的主要原因。为有效检测钻孔漏气通道,基于管流流体力学理论和漏气检测判别方法,研制了瓦斯抽采钻孔漏气通道检测装置。通过检测不同钻孔深度气样参数并分析其分布规律和突变情况,确定抽采钻孔失效原因和漏气通道位置;检测装置采用高稳压阻式压力传感器、激光甲烷传感器和荧光氧气传感器实现抽采负压、瓦斯浓度和氧气浓度检测,并采用1.5 m/节快接式25 mm薄壁不锈钢管作为取气管件,钻孔检测深度达30 m。现场应用结果表明,抽采管段检测参数变化稳定,说明抽采管未发生破损或接口漏气等,抽采管密封效果较好;在封孔段,距孔口9~18 m范围内存在多处不同程度的突变点,最大漏气通道在距孔口9~12 m范围内,说明原封孔深度不足,原封孔工艺无法有效密封漏气通道。将封孔深度增加至12 m,并采用“两堵一注”带压注浆封孔工艺,进行对比试验,结果表明,改进后试验钻孔整体抽采效果大幅改善,孔口瓦斯体积分数提升至55%以上,在距孔口12 m以深范围内瓦斯体积分数变化稳定,氧气体积分数近乎为0,漏气通道减少。试验结果验证了瓦斯抽采钻孔漏气通道检测装置能够有效检测漏气通道,为有针对性地调整封孔方式和相关参数及后续改进工作提供依据。     

Optimization of Sampling Resources

T his paper reports on an investigation into the efficient routing of sample collection in the Lincoln Division of Anglian Water. Samples have to be collected from more than 600 sample points across three functions and at frequencies ranging from daily to once in two years. The organization of this activity is clearly complex.
As a result of the review carried out using manual methods, the additional 15 000 water samples which are required annually are now being collected with no increase in staff resources. The scale of the effort required for this review prevents it from being repeated except at infrequent intervals; yet without frequent reviews the efficiency of routes is eroded as the required pattern of samples changes. A computer system is therefore being developed, offering the prospect of halting the drift away from efficiency and the speedy evaluation of alternative strategies.     

The Installation and Use of a Snow Pillow to Monitor Snow Water Equivalent

In February 1993, a snow pillow was installed at Widdibank Fell near Cow Green reservoir (in Upper Teesdale) to monitor snow water equivalent.
This paper describes existing snow-measurement techniques in the UK and the site-selection process and installation details for the snow pillow. Following a winter of more than 100 days with snow cover at the site, the success of the pillow in representing site and catchment snow conditions and in providing operationally useful snowmelt information for flood warning has been assessed.