Optimization of the procedure for obtaining DPSCs by means of fragile fracture in clean room conditions

2014 ◽  
pp. 265-268 ◽  
Keyword(s):  
Clean Room ◽  
Fragile Fracture

Insights into the Microbial Diversity and Bioburden in a South American Spacecraft Assembly Clean Room

Astrobiology ◽  
2013 ◽  
Vol 13 (12) ◽  
pp. 1140-1154 ◽  
Author(s):  
Petra Schwendner ◽  
Christine Moissl-Eichinger ◽  
Simon Barczyk ◽  
Maria Bohmeier ◽  
Rüdiger Pukall ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
South American ◽  
Clean Room ◽  
Spacecraft Assembly

Emergency Ventilation of Clean Rooms

2021 ◽  
pp. 70-77
Author(s):  
В. М. Попов ◽  
А. В. Бараков ◽  
С. Н. Кузнецов
Keyword(s):  
Influencing Factors ◽  
Material Balance ◽  
Emergency Situation ◽  
The State ◽  
Clean Room ◽  
Toxic Gases ◽  
Emergency Ventilation ◽  
Modern Industry ◽  
Air Exchange

Постановка задачи. В современной промышленности для обеспечения контроля за состоянием воздушной среды часто используют технологии чистых помещений. Использование токсичных газов в чистых помещениях может приводить к аварийным ситуациям, для ликвидации которых необходима аварийная вентиляция. Для расчета аварийного воздухообмена необходимо создание модели аварийного воздухообмена, учитывающей значительное количество влияющих факторов. Результаты. Модель аварийного воздухообмена для чистого помещения разработана на основе уравнения материального баланса по вредному газу, выделяющемуся из оборудования при возникновении аварийной ситуации. Получено решение модели аварийного воздухообмена для чистого помещения, позволяющее рассчитать концентрации вредного газа в зависимости от расчетной аварийной ситуации. Исследованы свойства полученного решения. Введено понятие аккумулирующей способности вентилируемого помещения и оценено влияние аккумулирующей способности на изменение концентраций вредного газа. Выводы. Выполненные расчеты позволяет глубже понять процессы развития аварийной ситуации в чистом помещении и учесть эти риски при проектировании аварийной вентиляции чистых помещений. Statement of the problem. In modern industry, clean room technology is commonly used to monitor the state of the air. The use of toxic gases in clean rooms might result in emergencies that call for emergency ventilation. In order to calculate the emergency air exchange, it is necessary to design a model of emergency air exchange considering a significant number of influencing factors. Results. The model of emergency air exchange for a clean room is developed based on the equation of material balance on the harmful gas allocated from the equipment in case of an emergency. The solution of the model of the emergency air exchange for a clean room is obtained allowing the concentrations of harmful gas to be calculated depending on a specific emergency. The properties of the resulting solution are investigated. The concept of accumulating capacity of the ventilated room is introduced and the influence of accumulating capacity on change of concentrations of harmful gas is evaluated. Conclusions. The performed calculations allow one to understand the processes of development of an emergency situation in a clean room more profoundly and to allow for these risks while designing emergency ventilation of clean rooms.

scholarly journals Separation and 14C Dating of Pure Pollen from Lake Sediments: Nanofossil AMS Dating

Radiocarbon ◽  
1992 ◽  
Vol 34 (3) ◽  
pp. 557-560 ◽  
Author(s):  
Austin Long ◽  
Owen K. Davis ◽  
Jeanne de Lanois
Keyword(s):  
Organic Matter ◽  
Lake Sediments ◽  
Mono Lake ◽  
Bulk Sediment ◽  
Clean Room ◽  
14C Dating ◽  
Ams Dating

We have developed and tested a practical device for manually separating pollen from pollen concentrates in sufficient quantity for AMS 14C dating. It is a combination of standard, commercially available equipment handled in a clean room by an individual trained to recognize pollen. A typical example requires about 15–20 h of hand-picking under the microscope. We show the usefulness of this procedure with results on a mid-Holocene segment from a core from Mono Lake. Sediments from this hardwater lake contain pollen and finely disseminated organic matter, but no macrofossils. The pollen dated ca. 1000 yr younger than the bulk sediment. The sediment “date” is most likely affected by incorporation of limestone-derived carbon, and is erroneously old.

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