BYJ型防喷脱接器的设计与应用

本文介绍了BYJ型防喷脱接器的结构和工作原理。它既有抽油杆与大泵活塞脱接功能,又能实现不压井作业施工,是大型抽油泵理想的配套工具。现场应用表明,该防喷脱接器对接成功率较高,并实现了大泵井不压井施工。     

糖化酶制剂辐照性能研究

研究了工业糖化酶制剂经辐照处理后各项性能的变化。结果表明,经2kGy以下剂量的γ射线处理后,可提高其贮存稳定性,改善卫生品质,不影响其正常使用。     

Observation of atomic steps on CaCO3 crystal surface

By using scanning polarization force microscopy,the deliquescence process and the atomic steps on the cleavage surface of CaCO3 in air were studied in situ.Under an exposure to medium umidity(-57%),the sloiw step movement has been observed.     

草酸二乙酯气相催化加氢合成乙二醇的研究

对草酸二乙酯气相催化加氢生成乙二醇反应进行了实验研究。研制了不含铬的铜基催化剂,并考察了催化剂的制备条件对反应结果的影响。结果表明,Cu/SiO_2质量比为0.67,活化温度为350℃时最佳。在上述催化剂制备的基础上,提出了最佳反应条件。     

Synthesis, characteristics and oxygen-sensitive properties of SrMgxTi 1 − xO3 nanocrystals

SrMg_xTi_{1 - x}O₃ nanocrystals (x = 0.1–0.6) were synthesized by the stearic acid gel method. Powder samples were characterized by X-ray diffraction and X-ray photoelectron (XP) spectroscopy. The results showed that the lattice parameter a and the O 1s XP spectrum changed not only with the Mg content x but also with the grain size d of the samples. The conductivity of a thick film specimen fabricated on an aluminium oxide wafer was investigated in a nitrogen—oxygen atmosphere.     

A clinical study in the treatment of acute bacterial infections with fleroxacin

The purpose of this clinical trial is to evaluate the efficacy and safety of fleroxacin and to compare with those of lomefloxacin. A randomized controlled study was carried out to treat sixty patients with urinary tract and respiratory tract bacterial infections, thirty in each group with one of the two drugs, and fifty cases were treated with fleroxacin in an open trial. Altogether there were one hundred and ten cases. Both fleroxacin and lomefloxacin were given orally, the dosage was 200 mg every 12 hours or 400 mg every 24 hours for 7-14 days. The clinical efficacy rate was 93.3%; the culturing rate in the fleroxacin group was 83.3%; the bacterial clearance rate was 92.3%, the incidence of adverse reactions was 9.4%, while in the lomefloxacin group they were 90.0%, 80.0%, 87.5% and 6.7% respectively, with no statistically significant difference between the two groups (P > 0.05). In the open and randomized trials, fleroxacin cured eighty cases of bacterial infections, the overall clinical efficacy rate was 90.0%, the culturing rate in the flero-xacin group was 83.8%, the bacterial clearance rate was 88.2% and the incidence of adverse reactions was 9.6%. It is shown that fleroxacin is an antibiotic of broad-spectrum, high efficacy and safety.     

Study on Factors Affecting the Structure of High SpeedSteel Ingot Produced by ESR

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小方坯连铸机的PLC自动控制

本文对弧型小方坯连铸机工艺与设备进行了分析，介绍了连铸生产的ＰＬＣ控制系统。及其软件设计。