9 research outputs found
МИКРОВОЛНОВОЙ БЕСКОНТАКТНЫЙ МЕТОД ИЗМЕРЕНИЯ УРОВНЯ ВЕЩЕСТВ
The analysis and comparison of existing contactless methods of substance level measurement is carried out. Advantages and lacks of optical, ultrasonic and microwave measurement methods are considered in details. The conclusion about expediency of a certain use contactless method of level measurement depending on set conditions is made. Microwave methods of substance level measurement are allocated as the most universal and perspective. А microwave contactless measuring instrument of substances level is considered.Проведен анализ и сравнение существующих бесконтактных методов измерения уровня вещества. Подробно рассмотрены преимущества и недостатки оптических, ультразвуковых и микроволновых методов измерения. Сделано заключение о целесообразности использования определенного бесконтактного метода измерения уровня в зависимости от заданных условий. Микроволновые методы измерения уровня вещества выделены как наиболее универсальные и перспективные. Рассмотрен СВЧ бесконтактный измеритель уровня веществ
ИССЛЕДОВАНИЕ ОСНОВНЫХ ХАРАКТЕРИСТИК УМНОЖИТЕЛЕЙ ЧАСТОТЫ В ДИАПАЗОНЕ 120-220 ГГЦ
The features of the design and the operation principle of frequency doublers in range 120-220 GHz are considered. The results of input and output power measurements of frequency doublers are given, the values of them efficiency factors are calculated. A technique for measuring and estimating the results of the deviation of the efficiency is developed. The dependence of the transmission coefficients from the value of the output power of the frequency doublers is investigated.Рассмотрены особенности конструкции и принципа работы удвоителей частоты в диапазоне частот 120-220 ГГц. Приведены результаты измерений входной и выходной мощности удвоителей частоты, рассчитаны значения их коэффициентов передачи по мощности. Разработана методика измерений и оценки результатов отклонения коэффициента передачи по мощности удвоителей частоты. Исследованы зависимости коэффициентов передачи по мощности от значения выходной мощности удвоителей
MICROWAVE CONTACTLESS MEASUREMENT METHOD OF SUBSTANCES LEVEL
The analysis and comparison of existing contactless methods of substance level measurement is carried out. Advantages and lacks of optical, ultrasonic and microwave measurement methods are considered in details. The conclusion about expediency of a certain use contactless method of level measurement depending on set conditions is made. Microwave methods of substance level measurement are allocated as the most universal and perspective. А microwave contactless measuring instrument of substances level is considered
Investigation of main characteristics of frequency multipliers in the range of 120-220 GHz
The features of the design and the operation principle of frequency doublers in range 120-220 GHz are considered. The results of input and output power measurements of frequency doublers are given, the values of them efficiency factors are calculated. A technique for measuring and estimating the results of the deviation of the efficiency is developed. The dependence of the transmission coefficients from the value of the output power of the frequency doublers is investigated
AUTOARTERIAL PLASTY OF EXTERNAL CAROTID ARTERY IN CASE OF STENOSIS AND INTERNAL CAROTID ARTERY OCCLUSION
The research proved an efficacy of autoarterial plasty performance of external carotid artery in case of internal carotid artery occlusion. It isn’t necessary to apply synthetic materials or an autovein for closing arteriotomic defect in plasty performance. According to data of ultrasonic scintiangiography and transcranial Doppler graphy, there was noted the significant increase of blood flow on medial cerebral artery in operated area after a year of surgical treatment (about 30%). Proposed operation is effective in prevention plan of ischemic stroke
EFFICACY OF CLASSICAL CAROTID ENDARTERECTOMY USING TEMPORARY SHUNT
The study generalized the 15-year experience of classical carotid endarterectomy performance with application of a temporary carotid shunt and an autovenous path in 325 patients. There were analyzed the more frequent complications in standard groups. Advantages of given method were determined and it was specified the ways, which facilitated to reduction of intraoperative risks and increase of technical quality realization of different stages of surgery
COMPARISON OF LONG-TERM RESULTS OF FEMORAL VEIN LIGATION AND TRANSCATHETER THROMBOLYSIS IN THROMBOSIS OF THE FEMORAL SEGMENT
INTRODUCTION. The problem of preventing massive pulmonary thromboembolism and post-thrombotic syndrome in deep vein thrombosis has been studied for a long period. The introduction of new treatments for deep vein thrombosis requires a detailed comparison of their effectiveness.The OBJECTIVE of this work was a comparative analysis of ligation of the superficial femoral vein and regional thrombolytic therapy.MATERIAL AND METHODS. A retrospective multicenter study involving 30 patients with femoproplite thrombosis, who had received catheter-directed thrombolysis or ligation of the superficial femoral vein, was performed. The investigated patients underwent inpatient treatment.RESULTS. The data on the effectiveness of both methods in preventing pulmonary thromboembolism were obtained. When comparing both groups, we revealed a statistically significant difference in the frequency of the development of PTS and the severity of its development in 1 year after treatment. With ligation vein, 73.3 and 6.7% in the thrombolysis group (p=0.0005).CONCLUSION. Regional thrombolysis was an effective treatment for deep vein thrombosis and prevention of PTS.The authors declare no conflict of interest.The authors confirm that they respect the rights of the people participated in the study, including obtaining informed consent when it is necessary, and the rules of treatment of animals when they are used in the study. Author Guidelines contains the detailed information
WAYS OF IMPROVEMENT OF LOOP ENDARTERECTOMY RESULTS FROM ILIAC-FEMORAL SEGMENT
The article presents an analysis of treatment results of 91 patients with iliac-femoral segment artery occlusion at the period from 2008 to 2014. Patients were divided into 2 groups: main group (n=30) consisted of patients who undergoing a half-closed loop endarterectomy with following implantation of stent-grafts in this area and control group (n=61) had patients whom were performed routine half-closed loop endarterectomy. The II degree of ischemia of lower extremities was in 88 (96,7%) patients and III degree had 3 (3,3%) patients. The areas of abnormalities of intravascular pattern were detected in 100% of cases in intraoperative angiography. They were modified using stent-grafts. A primary vascular patency was 100% in the first group and it numbered 65% in the second group during 5 years. The intraoperative angiography control with stent-graft implantation to the area of endarterectomy allowed reliable improvement of treatment results
SIMULTANEOUS REVASCULARIZATION OF AORTOFEMORAL AND FEMOROPOPLITEAL ARTERIAL SEGMENTS BY SEMICLOSED LOOP ENDARTERECTOMY
OBJECTIVE. The authors would like to consider the possibility and feasibility of simultaneous revascularization of two arterial segments in patients with lower extremity arterial occlusive disease by method of semiclosed loop endarterectomy. MATERIALS AND METHODS. The research included 143 patients. Revascularization of aortofemoral segment was performed on 67 patients. The simultaneous revascularization of aortofemoral and femoropopliteal segments was carried out for 76 patients. The follow-up period was 5 years. RESULTS. There was revealed that the long-term results of multilevel reconstruction were worse that single-level reconstruction. This method requires an individual approach. The best results of simultaneous interventions were obtained in patients aged 60 and older with the III stage of chronic limb ischemia and 2 or 3 working shin arteries. The worst results were observed in patients younger than 50 year old with IV stage of critical limb ischemia and significant lesions of shin arteries