Dissipative heating of a hollow viscoelastic cylinder subjected to the action of normal loads moving along its surface with constant angular velocity

We consider a two-dimensional quasistatic problem of the stress-strain state and dissipative heating of a hollow circular viscoelastic cylinder subjected to the action of two, normal diametrically opposite loads moving along the surface of the cylinder with constant angular velocity. It is assumed that the physicomechanical properties of the material are independent of temperature. In this case, the combined problem of thermoviscoelasticity splits into two linear problems: the problem of the stress-strain state of the cylinder without axial symmetry and the axisymmetric problem of heat conduction with temperature averaged over a cycle and a known heat source. The exact solutions of these problems are obtained. The influence of both the coefficient of heat transfer on the inner boundary of the cylinder and the sizes of the cylinder on the temperature of dissipative heating are investigated. Timoshenko Institute of Mechanics, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Problemy Prochnosti, No. 2, pp. 67–73, March–April, 1999.     

间规1,2—聚丁二烯合成的实验室研究

报道了使用Ｃｏ－Ａｌ－Ｐ－Ｈ２Ｏ催化体系实验室合成间规１，２－取丁二烯的研究结果，详细讨论了催化组分的加料顺序，老化条件及聚合工艺条件对聚合反应的影响，在此基础上得到最佳工艺条件，进行了模试放大，所得聚合物的基本性能与ＪＳＲ ＲＢ８２０相近。     

Nitric oxide synthase in neuroepithelial brain tumors

Immunohistochemical investigation of NO-synthase in brain astrocytic tumors revealed intense reaction in many tumor cells as well as direct correlation in the intensity of reaction and the degree of tumor anaplasia. Grade I astrocytomas did not show immunoreactivity in contrast to high anaplastic tumors where many cells had positive reaction with a different degree of intensity. Positive immunoreaction was shown in many giant cells. Small cell glioblastomas and oligodendrogliomas were immunonegative. There was a direct correlation between NO-synthase expression and glial fibrillar acidic protein.     

磷块岩三轴压缩破坏特性与声发射规律的研究

采用应力加载系统和声发射测试系统,研究了三轴压缩试验中磷块岩裂纹破坏特性及声发射活动规律. 试验及分析研究表明:磷块岩三轴声发射加载全过程可分为裂隙压密阶段、弹性压缩阶段、裂纹初级扩展阶段、裂纹剧烈扩展阶段、宏观破坏阶段;磷块岩声发射事件在其强度最大阶段和宏观破坏阶段均有产生;磷块岩声发射事件数随着围压从2 MPa增加到4 MPa而减少.     

The late results of the surgical treatment of patients with a pathologically mobile kidney

Long-term (1-10 years) results of wandering kidney surgery were followed-up for 118 patients. The outcomes were found dependent on the duration of the disease, variety and severity of the lesion, age of the patients. The response appeared better in younger patients, in those with shorter duration of the disease and with unessential changes in the kidney. Recommendations are provided on the regimens, jobs, outpatient and inpatient follow-up for the subjects treated surgically for wandering kidney to reinforce the correction results achieved.