TPMS-based membrane lung with locally-modified permeabilities for optimal flow distribution

Membrane lungs consist of thousands of hollow fiber membranes packed together as a bundle. The devices often suffer from complications because of non-uniform flow through the membrane bundle, including regions of both excessively high flow and stagnant flow. Here, we present a proof-of-concept design for a membrane lung containing a membrane module based on triply periodic minimal surfaces (TPMS). By warping the original TPMS geometries, the local permeability within any region of the module could be raised or lowered, allowing for the tailoring of the blood flow distribution through the device. By creating an iterative optimization scheme for determining the distribution of streamwise permeability inside a computational porous domain, the desired form of a lattice of TPMS elements was determined via simulation. This desired form was translated into a computer-aided design (CAD) model for a prototype device. The device was then produced via additive manufacturing in order to test the novel design against an industry-standard predicate device. Flow distribution was verifiably homogenized and residence time reduced, promising a more efficient performance and increased resistance to thrombosis. This work shows the promising extent to which TPMS can serve as a new building block for exchange processes in medical devices

Совершенствование управления техническим состоянием магистрального нефтепровода при оптимизации работы станции катодной защиты

В процессе исследования проводились расчеты параметров катодной защиты магистрального нефтепровода, применение метода оптимизации работы станции катодной защиты. Приведены мероприятия по охране труда и безопасности проведения работ по обслуживанию станций катод-ной защиты, охране окружающей среды, технико-экономическая часть.In today’s world, a stronger demand for corrosion knowledge arises due to several reasons. Among them, the application of new materials requires extensive information concerning corrosion behavior of these particular mate-rials. Also the corro-sivity of water and atmosphere have increased due to pol-lution and acidification caused by industrial production. The trend in technolo-gy to produce stronger materials with decreasing size makes it relatively more expensive to add a corrosion allowance to thickness. Particularly in applica-tions where accurate dimensions are required, widespread use of welding due to developing construction sector has increased the number of corrosion prob-lems. Developments in other sectors such as offshore oil and gas extraction, nuclear power production and me

Химические элементы в воде объектов водопользования бывшего Семипалатинского испытательного полигона как фактор экологического воздействия

Изучен элементный состав вод объектов водопользования расположенных на территории бывшего Семипалатинского испытательного полигона. Содержание U, Mo и Sr в изученных водах имеют превышения над средним составом подземных вод зон гипергенеза и континентального засоления. Выделены химические показатели и элементы превышающие ПДК это минерализация, общая жесткость, сульфаты, натрий и уран.The elemental composition of the water of odjects of water use in the territory of the former Semey test site was studied. The content of U, Mo and Sr in the studied waters has an excess over the average composition of groundwater in the areas of hypergenesis and continental salinization. Chemical indices and elements above MPC are identified as mineralization, total hardness, sulfates, sodium and uranium