Determination of the effective porosity of a single filter fiber

In this work, a numerical simulation of the aerosol motion when flowing around a single porous filter fiber with a diameter of 5 mm is carried out. The fiber is formed by a set of microfibers in a random arrangement. The size of the microfibers varies from 0.1 mm to 0.5 mm. For each fixed size of microfibers, a fiber model with different porosity of the medium was created. The porosity ranged from 0.7 to 0.9. The calculations were carried out in the ANSYS software package (v. 19.0). Studies have shown that a porous filter fiber model provides the maximum deposition efficiency for highly inert particles is provided by a porous filter fiber model with a microfiber size of 0.1 mm and a medium porosity of 0.9.

A New Fe-C Porous Filter Material From Dredged Sediment: Preparation, Characterization, And Its Application

A new Fe-C porous filter material was prepared with dredged sediment of river as raw material. The orthogonal test L9(34) and component ratio experiment of raw material were conducted to investigate the optimum technological condition. Further, the filter obtained was characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscope (EDS), and X-ray diffraction (XRD). Results showed that the optimal technological condition was sludge: straw: starch: iron powder: foam: iron powder 74.5∶10∶7.5∶3∶5, preheating temperature 280 ℃, preheating 15 min, sintering temperature 1080 ℃, and sintering 11 min. The BET surface area of the filter was 3.32 m2 g− 1, and average pore size was 10.05 nm. Phase composition mainly included SiO2, Fe3O4, Fe2O3 and muscovite (KAl2(Si3Al)O10(OH)2). Average effluent concentrations of total phosphorus (TP), total organic carbon (TOC), and total nitrogen (TN) of the biofilter system filled with the filter obtained were decreased to 0.08, 3.43, and 3.76 mg L− 1, separately, at hydraulic retention time 4 h. Thus, the filter prepared with dredged sediment of rive as raw material is an alternative material for polluted river water purification.

Detection of Circulating Tumor Cells in Resectable Pancreatic Ductal Adenocarcinoma: A Prospective Evaluation as a Prognostic Marker

Circulating tumor cells (CTCs) are useful biomarkers of many solid tumors, but are infrequently detected in early stage pancreatic ductal adenocarcinomas (PDACs). The first drainage of pancreatic venous blood flow come to portal vein and pass through the liver, and they finally go out for peripheral blood. We thought that comparing CTCs from portal vein and peripheral blood could enable us to understand the clinical meaning of CTCs from each different site in PDACs. Therefore, we aimed to determine 1) whether CTCs could be reliably identified in early stages (operable) of PDACs, 2) if there are any differences in the detected number of CTC in portal vein blood and peripheral blood, and 3) whether CTCs can be sensitive biomarkers for the prognosis of resectable PDAC patients. Newly diagnosed PDAC patients who underwent operation with curative intention between 2013 and 2015 were prospectively enrolled. Blood draws from portal and peripheral vein ran through the microfabricated porous filter, and anti-epithelial cell adhesion molecule (EpCAM) and anti-Plectin-1 antibodies were used for CTC identification. Baseline clinical characteristics, tumor characteristics, treatment, and clinical outcomes were assessed. The clinical stages of the 32 enrolled patients were as follows: IA/IB 1 (3.1%); IIA 9 (28.1%); IIB 17 (53.1%); III 5 (15.6%). Twenty-seven patients (84.4%) received R0 resection, while five patients (15.6%) received R1 resection. EpCAM+ CTCs were detected in 20 portal blood (62.5%) and 22 peripheral blood (68.8%). Plectin-1+ CTCs were identified in 14 portal blood (43.8%) and 16 peripheral blood (50%). Plectin-1-expressing CTCs were picked from CTC platform (microfabricated porous filter) and we could find out all KRAS mutation. Patients with detectable EpCAM+ CTC less than one in peripheral blood showed longer overall survival (OS) compared to patients with detectable CTCs more than one (35.5 months vs. 16.0 months). EpCAM and Plectin-1 successfully identified CTCs at the early stage of PDACs. Also, the number of CTCs could be a prognostic marker for survival in resectable PDACs.

Studi Perbandingan Efisiensi Perbaikan Mutu Air Limbah Domestik melalui Filtrasi Horizontal dengan Beton Porous Recycled Aggregate Berlapis

Pencemaran air limbah domestik menjadi salah satu sebab penurunan Indeks Kualitas Air nasional. Peningkatan jumlah penduduk dengan fasilitas sanitasi yang kurang layak menjadikan diperlukannya solusi. Beton porous dengan agregat RCA memiliki potensi untuk memperbaiki air buangan rumahan. Terbuat dari beton porous, filter dibuat dengan dimensi 40×40×5 cm3 menggunakan agregat RCA bergradasi butiran 0,5-2,0 cm. Dua model reaktor berukuran sama disiapkan, berisi 3 dan 4 lapis filter. Air limbah domestik sebagai benda uji berasal dari MCK Terpadu Tlogomas, dialirkan secara menerus ke dalam model. Hasil Uji 1 menunjukkan Model Reaktor 3 Filter mampu memperbaiki nilai pH dan COD sesuai baku mutu, sedangkan Model Reaktor 4 Filter hanya dapat memperbaiki nilai pH. Hasil Uji 2 menunjukkan Model Reaktor 3 Filter mampu memperbaiki nilai pH dan TSS sesuai baku mutu, sedangkan Model Reaktor 4 Filter hanya dapat memperbaiki nilai pH. Efisiensi rerata filtrasi terhadap influen menunjukkan bahwa Model Reaktor 3 Filter lebih baik daripada Model Reaktor 4 Filter dengan persentase perbaikan pH 11,54%, BOD 26,15%, COD 20,79%, dan TSS 46,37%.