变压吸附制氧法在冶金上的应用

介绍变压吸附制氧法的原理，工艺流程，设备，技术经济指标，以及在我国的发展和应用现状，该法与传统的深冷制氧法比较，具有基建设资少，运行成本低，自动化程度高，产氧快，安全可靠等优点，适合冶金工厂应用。     

HX-6000型VPSA-O2真空变压吸附制富氧装置的设计与应用

介绍了6000m3/h真空变压吸附制氧装置的基本原理、工艺流程,对吸附法和深冷法的特点进行了比较。     

HX-6000型VPSA-O2真空变压吸附制富氧装置的设计与应用

介绍了6000m3/h真空变压吸附制氧装置的基本原理、工艺流程,对吸附法和深冷法的特点进行了比较.     

变压吸附制氧法在冶金上的应用

介绍变压吸附制氧法的原理、工艺流程、设备、技术经济指标 ,以及在我国的发展和应用现状。该法与传统的深冷制氧法比较 ,具有基建投资少、运行成本低、自动化程度高、产氧快、安全可靠等优点 ,适合冶金工厂应用。     

变压吸附制氧法与深冷法的比较

全面比较变压吸附制氧法与深冷法的工艺过程、运行参数、技术指标、水电消耗、基建投资、经营成本、技术安全、占地面积、建设要求、操作维护和操作人数等，指出各自的优缺点和适用范围，供用户选择时参考。     

变压吸附制氧高炉富氧设计应用

通过分析变压吸附制氧与深冷制氧的区别,结合南钢高炉富氧实际需求,采用变压吸附制氧的设计,实现高纯氧与新上富氧双组合模式,并可同时进行互换。在降低能耗的同时,保证公司总体高炉用氧最优化运行。     

变压吸附制氧技术的发展

概述了变压吸附制氧技术的发展,分别对变压吸附制氧设备的应用领域、工艺设计和选型进行论述,简要介绍了变压吸附制氧设备的特性.     

变压吸附制氧技术的发展

概述了变压吸附制氧技术的发展,分别对变压吸附制氧设备的应用领域、工艺设计和选型进行论述,简要介绍了变压吸附制氧设备的特生。     

变压吸附制氧在高原地区再生铅回收领域的应用

铅冶炼工艺中易产生硫、铅、砷等污染，对环境造成极大影响，而富氧侧吹熔池直接熔炼技术则可提高生产效率、降低能耗、节约成本、减少污染。其中氧气由真空变压吸附制氧(VPSA)设备获取。变压吸附制氧具有工艺流程简单、投资小、能耗低、产量纯度可调、灵活性好等多方面优势，在国内低海拔地区的应用较为稳定，而在高原地区应用不佳，北大先锋研发的纯度80%的变压吸附制氧设备解决了这一难题。本文介绍了再生铅回收领域中富氧侧吹熔池熔炼直接炼铅和变压吸附制氧的工艺流程、特点，以及变压吸附制氧技术在高原地区该领域的具体应用。通过采用高效PU-8型锂基制氧分子筛及两塔吸附流程，配以适宜的鼓气系统、脱附系统、压氧系统、放空系统，VPSA制氧站弥补了2 500 Nm³/h的用氧缺口，解决了燃烧不充分的问题，提高了烟尘燃烧效率，节省焦炭约10%,降低成本约8%,满足高原地区再生铅行业用户的用氧需求。     

3200m^3／h真空变压吸附富氧装置的运用

通过介绍贵阳特殊钢有限公司新建成的3200m^3/h真空变压吸附装置的基本原理，工艺流程以及设备在炼钢上的应用，比较了吸附法相对深冷法的优越性。     

变压吸附制氧机组在金银提取上应用展望

介绍变压吸附制氧和富氧浸出金银的原理、设备和优点，列出三个厂应用该设备后所取得的圆满结果，指出变压吸附制氧机组在金银提取上极具推广价值。     

Ventriculophasic modulation of atrioventricular nodal conduction in humans

BACKGROUND: Baroreceptor-mediated phasic changes in vagal tone have been hypothesized to cause ventriculophasic sinus arrhythmia (VPSA). The objectives of this study were to demonstrate ventriculophasic modulation of AV nodal conduction and to substantiate the role of the baroreflex on ventriculophasic AV nodal conduction (VPAVN) by pharmacological perturbation of parasympathetic tone. METHODS AND RESULTS: Twelve patients with infra-Hisian second-degree heart block and VPSA were studied. Incremental atrial pacing was performed until AV nodal Wenckebach block at baseline, after phenylephrine infusion, and after atropine. AV nodal conduction curves were constructed for each phase and compared. At baseline, VPAVN was present in 9 of 12 patients on the steep portion of the AV nodal conduction curves. Phenylephrine increased systolic blood pressure from 149+/-33 to 177+/-22 mmHg (P<0.001) and sinus cycle length from 844+/-169 to 1010+/-190 ms (P<0.001) and shifted the AV nodal conduction curves up and to the right. Phenylephrine induced VPAVN in 2 of 3 patients in whom it was not present at baseline and in 11 of 12 total. Atropine abolished both VPSA and VPAVN in all patients. CONCLUSIONS: VPAVN was demonstrated in patients with infra-Hisian second-degree AV block. It was accentuated by phenylephrine and abolished by atropine, suggesting a baroreflex mechanism for VPSA and VPAVN.     

低纯度氧化在70tUHP电炉上应用分析

介绍了把真空变压吸附（VPSA）制取的低纯度氧化应用在70t超高功率电弧炉的情况,理论分析了钢中碳氧反应和钢中氮气的含量的变化,并对其进行了实际检测。理论和生产实践结果分析表明：采用VPSA制取的低纯度氧化代替纯氧在70t超高功率电弧炉上炼钢是可行的,并能够取得明显的经济效益。     

节能型真空变压制氧（ＶＰＳＡ—Ｏ２）技术

本介绍了真空变压吸附制氧的原理、工艺流程及节能效果,阐述了ＶＰＳＡ－Ｏ２的特点及选型原则。     

VPSA变压吸附制氧技术在贵冶厂的应用实践

本文简要介绍了贵冶制氧车间新投入的变压吸附制氧机的工艺原理 ,半年多的运行实践及存在问题。     

基于轻组分充压的改进型三塔真空变压吸附工艺富集煤矿乏风瓦斯的实验研究

建立了以活性炭为吸附剂的三塔真空变压吸附实验装置,对循环过程中的充压方式和抽真空排放过程进行了实验研究.采用轻组分从吸附塔上端充压可以在排放气甲烷体积分数相同的情况下,延长穿透时间,提高产品气甲烷体积分数;而在循环中引入抽真空排放步骤也可以在不改变吸附与解吸压力的情况下有效提高产品气中甲烷的体积分数.在此基础上,对同时包含排放气充压步骤和抽排步骤的三塔变压吸附循环流程进行了实验研究.实验结果表明,应用该循环可以在吸附和解吸压力分别为140 kPa和20 kPa条件下将甲烷体积分数为0.2%的乏风瓦斯富集至0.654%,同时甲烷回收率在65%.      

乏风瓦斯分离富集用椰壳基活性炭的制备

以椰壳为原料、酚醛树脂为粘结剂及聚乙二醇（PEG）为造孔剂和分散剂,采用水蒸气活化制备活性炭,以所制备的活性炭为吸附剂,采用真空变压吸附法（VPSA）对乏风瓦斯进行分离富集.分别考察了不同活化条件对活性炭孔结构性能的影响,以及不同VPSA操作条件对乏风瓦斯富集效果的影响.结果表明:以酚醛树脂与粉体炭的质量比为0.5 g/g制备的成型炭作为炭质前驱体进行活化,在活化时间为5 h、通入水量为1.96 cm3/min和活化温度为825 ℃的条件下制备的活性炭,其对应的比表面积、微孔体积及微孔率分别达到795 m2/g、0.37 cm3/g和84.1%;并以该活性炭为吸附剂,在最佳操作条件下,乏风瓦斯（甲烷含量约0.5%）经富集后,产气中CH₄浓度和回收率分别为1.51%和96%.      

A method of two-dimensional measurement for evaluating finger motion impairment. A description of the method and comparison with angular measurement

A new method has been designed for direct measurement of the two-dimensional range of motion (ROM) of the finger. The two-dimensional method encompasses the postures imposed by various combinations of contraction and relaxation of the finger motors, so that an individual muscle injury or adhesion might be more easily detected. The figures and values obtained from the two-dimensional method are easier to interpret than those from conventional measurements, making the progress of the rehabilitated finger more apparent. Since the passive ROM cannot be evaluated by this method, it is a supplement rather than a substitution for the conventional range of motion evaluation for each joint. The drawback of the two-dimensional method is that it is more difficult to use than the conventional method.     

湿法炼锌过程中砷分析方法的改进

古蔡法测砷简单快速,但误差较大,而AgDDTC分光光度法测砷准确度高,但操作较繁琐。将这两种常用的砷分析测定方法进行综合改进,测定的结果更加准确,操作更加简便。     

Emergency contraception: is it time to change method?

The Yuzpe method of using combined oral contraceptives for emergency contraception has been available for 25 years; prevents 75% of pregnancies that would have occurred if no treatment were used; has an excellent safety record; and is contraindicated only in patients with a history of thromboembolism, migraine at presentation, or a history of migraine with aura. However, this method has side effects of nausea and vomiting, and the World Health Organization recently reported that use of levonorgestrel alone is effective and associated with fewer side effects. No additional research has been conducted on the timing or dosage of the estrogen-progestogen method, but some dose-effectiveness studies have been performed on mifepristone. Mifepristone, however, is not widely available. The levonorgestrel studies found a negative correlation between the interval from unprotected intercourse to treatment and effectiveness but concluded that levonorgestrel was more effective than the combined method (this study found a lower effectiveness for the combined method than previously reported). Given that each method is effective, consideration of whether the new one should be adopted must take into account the fact that the levonorgestrel is currently not licensed for this use, is not prepared in convenient dosages, and is more expensive and less available. Introduction of new methods of emergency contraception should augment choices rather than replace other methods.