The origin ofhigh hydraulic resistance for filter cakes ofdef ormable particles: cell-bed deformation or surface-layer effect?

This study reports a numerical approach for modeling the hydraulic resistance ofa filter cake ofdef ormable cells. First, a mechanical and osmotic model that describes the volume fraction ofsolids in a bed ofyeast cells as a function ofthe compressive pressure it experiences is presented. The effects ofpressure on the compressibility ofyeast cells beds were further investigated both by filtration experiments and by centrifugal experiments based on the multiple speed equilibrium sediment height technique. When comparing the latter measurements with compression model calculations, we observed that the method based on centrifugal experiments suffers from rapid relaxation of the compressed bed. Concerning the filtration experiments, specific resistance ofwell-defined bed ofcells were calculated by a combination of the compression model with a formulation for hydraulic resistivity developed using the Lattice Boltzmann method. We further explain the experimental values observed for the hydraulic resistance ofcell beds, assuming that the first layer ofcells in contact with the membrane partially blocks the membrane area open to flow. In such a case, the blocked area seems to be a constant fraction of the normal cell–cell contact area

The Chao Phraya delta : historical development, dynamics and challenges of Thailand's rice bowl

The Chao Phraya basin has long been a water-deficity basin. Water stored in the Bhumipol and Sirikit dams only allow the irrigation of half of the delta, in average. The share of water available for agriculture in the delta is declining because of higher water abstraction both within the upper reaches of the basin and in Bangkok Metropolitan Area. The question of where, to whom, when and how this scarce resource is allocated is therefore of paramount importance. The paper first reviews the sectoral and spatial pattern of allocation in the last 25 years and assesses the efficiency and the equity of this allocation. It subsequently investigates all the options offered to increase management efficiency and proposes some guidelines for achieving higher equity and more even sustainability of farming systems. This includes technical, socio-institutional and economic issues. (Résumé d'auteur

Sludge drying reed beds for septage treatment: towards design and operation recommendations

International audienceWith decentralized treatment system development, a new concern emerges: the future of the septage. The aim of this paper is to assess the feasibility of septage treatment by SDRB, and to compare its efficiencies to those of activated sludge treatment in same conditions. The study took place on ten 2m² pilot-scales SDRB. Different designs and operation conditions have been tested on sludge treatment efficiency and will be presented as: (i) the top filtration layer (sand or compost), (ii) the load (from 30 to 50 kgSS/m-2/y). After one year and half commissioning period, we focus on the results obtained at nominal loads presenting: sludge characteristic, filtration efficiency, percolate quality and sludge deposit behaviour. Although results show better filtration efficiency for activated sludge (98.4%) than for septage (87.5%), the feasibility of septage treatment with drying reed bed has been demonstrated. Sludge accumulation is about 7.9 cm/y, when fed at 50 kgSS/m-2/y, and dry matter content of the sludge can reach 70% in summer period. The paper will present sludge characteristics, system efficiency, to finish on design and operation condition recommendations for SDRB treating septage

A Systems Approach to Assessing the Viability of Grazing Legume Systems Across Europe

Forage legumes are important in grassland farming throughout much of the world because of their ability to fix atmospheric nitrogen, and hence they are expected to play an increasingly prominent role in low- input grazing farming systems in Europe. Nevertheless, the socio-economic impact of the adoption of the new legume based grazing technologies have been poorly researched (Rochon et al., 2004). Thus a methodology has been developed to: * Assess the on-farm costs and benefits of including different legume crops for animal production;* Determine the types of management systems and environmental conditions under which forage legumes may play a major part as grazing crops in production systems in Europe;* and Determine the wider social, economic and environmental implication of widespread adoption of the new technologies

PENINGKATAN HASIL BELAJAR SISWA PADA MATERI BARISAN DENGAN MENGGUNAKAN MODEL PEMBELAJARAN PROBLEM BASED LEARNING

Penelitian ini adalah penelitian tindakan kelas yang bertujuan untuk meningkatkan hasil belajar siswa pada materi barisan dengan menggunakan model pembelajaran Problem Based Learning (PBL) di kelas XI SMA Negeri 12 Ambon.Penelitian ini dilaksanakan dalam 2 siklus.Setiap siklus dilaksanakan sebanyak 2 kali pertemuan termasuk pemberian tes akhir pada siklus I dan siklus II.Pengambilan data dilakukan dengan menggunakan tes hasil belajar dan lembar observasi.Data yang terkumpul dianalisis dengan menggunakan analisis kuantitatif dan kualitatif. Hasil penelitian ini menunjukan bahwa nilai persentase ketuntasan klasikal hasil belajar siswa kelas XI SMA Negeri 12 Ambon pada siklus I adalah sebesar 34,62%. Sedangkan nilai persentase ketuntasan klasikal hasil belajar siswa pada siklus II adalah 73,08%. Dengan demikian, hasil belajar siswa kelas XI SMA Negeri 12 Ambon pada siklus I ke siklus II mengalami peningkatan sebesar 38,46% melalui penerapan model Problem Based Learning (PBL

PENINGKATAN HASIL BELAJAR SISWA PADA MATERI PERSAMAAN DAN PERTIDAKSAMAAN LINEAR SATU VARIABEL MELALUI MODEL PEMBELAJARAN KOOPERATIF TIPE THINK TALK WRITE

This study aims to determine whether there is an increase in learning outcomes of seventh grade students of SMP Negeri 2 Ambon by using the Think Talk Write learning model on the material of One Variable Linear Equations and Inequalities. The subjects in this study were students of class VII-7 SMP Negeri 2 Ambon in the 2019/2020 academic year. This research is a classroom action research (PTK) with a teacher who acts as a teacher and takes place in 2 cycles. Data collection was carried out using tests and observation sheets. The data analysis technique used is quantitative and qualitative data analysis techniques. The results of data analysis show that there is an increase in learning outcomes from cycle I to cycle II, namely in cycle I the percentage of learning outcomes is 50% (15) of students who reach KKM ≥ 70 and the percentage of learning outcomes in cycle II is 73.33% (22) students who obtaining the value of student learning outcomes from cycle I to cycle II increased 23.33%. Thus the Think Talk Write (TTW) learning model can improve the learning outcomes of grade VII students of SMP Negeri 2 Ambon on the material of One Variable Linear Equations and Inequalitie

Studi Tindakan Penyaji Makanan Jajanan Dan Kandungan Scherichia Coli Pada Salome Di Taman Nostalgia Kota Kupang Tahun 2019

Taman Nostalgia Kota Kupang merupakan tempat pedagang kaki lima menjual salome. Sering dijumpai penjual salome yang menjual makanannya tanpa menggunakan penutup pada salome yang dijual. Lingkungan tempat penjualan juga yang kurang bersih, karena masih terdapat sampah pada beberapa tempat penjualan, lantai tidak kedap air, dan tempat penjualan yang tepat berada di samping jalan raya memungkinkan debu menempel pada makanan. Tujuan penelitian ini adalah Untuk mengetahui tindakan penyaji makanan dan kandungan Escherichia coli pada jajanan salome. Jenis penelitian yang digunakan adalah penelitian deskriptif. Variabel yang digunakan yaitu tindakan penyaji makanan dan kandungan Escherichia coli pada salome. Populasi dalam penelitian ini adalah 11 orang penyaji makanan jajanan salome dengan sampel yang diambil sebanhyak 11 sampel. Data hasil penelitian ini diperoleh dengan cara pemeriksaan lab dan pengisian ceklis. Data tersebut kemudian dibuat dalam bentuk tabel dan dianalisis secara deskrikriptif. Untuk data hasil lab dibandingkan dengan standar Kepmenkes RI No. 1098/MENKES/SK/VII/2013. Hasil penelitian ini menunjukan bahwa tindakan penyaji makanan jajanan salome di Taman Nostalgia Kota Kupang yang termasuk kategori baik sebanyak 9 (82%), kategori buruk sebanyak 2 (18%). Hasil pemeriksaan Escherichia coli pada jajanan salome yang ada di Taman Nostalgia Kota Kupang kategori memenuhi syarat sebanyak 6 (55%), dan kategori tidak memenuhi syarat sebanyak 5 (45%). Disarankan bagi penjamah makanan jajanan salome yang ada di Taman Nostalgia Kota Kupang sebagai bahan masukan agar memperhatiakan kebersihan tangan dan kuku (kuku dipotong pendek), menggunakan celemek, serta mnyediakan salome dan saos salome dalam keadaan tertutup

Gender and rural history: A roundtable

The aim of this debate article is to promote a discussion of a historiographical nature (not ideological, not political) about the meaning, place and role of gender in both the rural past and the rural historiography. The discussion revolves around a variety of questions, ranging from the relevance, the opportunity and the very history of the use of gender category in rural history, to the analysis of gender (im)balances in the community of historians working in this broadly defined field of studies, not to mention the very definition of what is meant by gender. These and other related topics, for which there are no single or definitive answers, are debated here in a roundtable format.info:eu-repo/semantics/publishedVersio