A Biogas Desulphurization System with Water Scrubbing

The biogas is renewable energy with very good potential. It is a gas produced by the bacteria transformation of the organic substance under the anaerobic condition. It is a flammable gas because it contains the hydrogen sulfide (H2S) in its composition. It will cause damage to metal equipment and the corrosion of the pipe. So before using the biogas, the desulphurization process should be carried on. The purpose of this study was to design a water scrubbing system for biogas and carry on the performance test of the desulphurization process in the hog farm. In the field test, the biogas flow rate is changed in the water scrubbing cylinder and under different external circulation water flow rate. The H2S concentration in the biogas is detected before and after water scrubbing, and the desulphurization efficiency of biogas was discussed, furthermore, the pH value of water in the water storage tank was measured. When the H2S adsorbed by water was at steady state, whether the pH value of external circulation water can meet the effluent standard was discussed. From the test results, it showed that the removal efficiency of H2S was 47.7% in 30 minutes of water scrubbing time under 120 ℓ of total water amount, 80 cm of water level in the water scrubbing cylinder, 20 ℓ/min of internal circulation water flow rate and 10 ℓ/min of external circulation water flow rate, and 25 ℓ/min of biogas flow rate. The pH value of water in the water storage tank was 6.22, which met the effluent standard of regulation for discharging directly. This system can reduce the H2S content in the biogas, and purify the quality of the biogas. The operation of this system is convenient and the fabrication cost is low, which is suitable for the small-scale hog farm to purify the biogas

Piglets Comfort with Hot Water by Biogas Combustion under Controllable Ventilation

The purpose of this study is to develop a hot-water heating system for pig farms which use biogas as the energy source while the air quality is regulated using an inverter-controlled fan. The biogas is a by-product from the 3-stage wastewater treatment process in regular pig farms. The biogas is burned for hot water which is circulated to warm piglet compartments with regulated, forced ventilation. The hot water is connected to a heat exchanger and hot air is hence blown into the pigsty. To maintain the pigsty at a comfort atmosphere, ventilation is regulated using an inverter-controlled fan. The mechanical ventilation is to be optimized as a compromise between indoor air quality and ventilation rate. The temperature uniformity and air quality in the pigsty is to be secured for comfortability. Experimental results show that hot water circulating at 0.043 m3/min and 60°C could keep the pigsty at 28°C for a stocking density of 1.77 pig/m2. Forced ventilation of 1.7 ACH (air change rate per hour) at 28°C could keep the pigsty comfort in terms of indoor temperature, relative humidity, and carbon-dioxide concentration

THE EFFECT OF PLYOMETRIC TRAINING FOR LOWER EXTREMITIES STRENGTH AND POWER IN HIGH-SCHOOL FEMALE BASKETBALL PLAYERS

Plyometric training is one of very prevailing training methods. It has its unique effect compared to other training methods. Having targeted 16 girl basketball players in senior high school, a set of box horse curriculum was designed with polymetric training for the study. The players were randomly divided into experimental groups (respectively with 30, 40, and 50 cm of box horse) and control group, four players for each group. Except for the control group, the other three groups had to receive 12 weeks of box horse training in addition to general basketball course training. The results of the study showed: Based on the plyometric training designed and applied to senior high school girl basketball players, this study shows that either CMJ or CJ has its effect

The flow and turbulence structure at a rectangular bridge pier with a low angle of attack

River hydrodynamicsInteraction with structure

Causal Evidence for the Role of Specific GABAergic Interneuron Types in Entorhinal Recruitment of Dentate Granule Cells

The dentate gyrus (DG) is the primary gate of the hippocampus and controls information flow from the cortex to the hippocampus proper. To maintain normal function, granule cells (GCs), the principal neurons in the DG, receive fine- tuned inhibition from local-circuit GABAergic inhibitory interneurons (INs). Abnormalities of GABAergic circuits in the DG are associated with several brain disorders, including epilepsy, autism, schizophrenia, and Alzheimer disease. Therefore, understanding the network mechanisms of inhibitory control of GCs is of functional and pathophysiological importance. GABAergic inhibitory INs are heterogeneous, but it is unclear how individual subtypes contribute to GC activity. Using cell-type-specific optogenetic perturbation, we investigated whether and how two major IN populations defined by parvalbumin (PV) and somatostatin (SST) expression, regulate GC input transformations. We showed that PV-expressing (PV+) INs, and not SST- expressing (SST+) INs, primarily suppress GC responses to single cortical stimulation. In addition, these two IN classes differentially regulate GC responses to θ and γ frequency inputs from the cortex. Notably, PV+ INs specifically control the onset of the spike series, whereas SST+ INs preferentially regulate the later spikes in the series. Together, PV+ and SST+ GABAergic INs engage differentially in GC input-output transformations in response to various activity patterns

On the Wind Reduction Effect of Windbreak Nets in Front of the Simple Greenhouse for Planting Fruits and Vegetables

The island of Taiwan experiences frequent strong winds coming with typhoons in the summer and with northeast monsoons in the winter. The strong winds are hazardous to the structure of a simple greenhouse that is widely used for vegetable and fruit plantation. The damage may reduce agricultural yields. Windbreak netting is a practical procedure for protecting a greenhouse from strong winds. The purpose of this study is to carry on the wind tunnel simulation test of windbreak nets in front of the simple greenhouse. Windbreak nets of densities 50%, 40%, 30% and 20% had a uniform dimension of 10 cm (per unit 1 h) in height and 29.2 cm in width. A windbreak net was tested at tilt angles of 0o, 5o, 10o and 15o. The wind tunnel simulation test is carried on at 10 m/s of reference wind velocity. The wind velocities at different horizontal distances and vertical distances front and behind the windbreak net are measured. The relative wind velocity is calculated. The wind reduction effect at different horizontal distances behind the windbreak net is analyzed and discussed. From the test results, it is known that when the tilt angle of windbreak net is 0o and the height of windbreak net is 1h, the corresponding wind reduction effect of windbreak nets with 20%, 30%, 40% and 50% porosity is 62%, 61%, 59% and 52% respectively at 2h horizontal distance. The corresponding wind reduction effect of windbreak nets with 20%, 30%, 40% and 50% porosity is 46%, 45%, 40% and 32% respectively at 10h horizontal distance. However, the increase of tilt angle of windbreak net does not have much influence on the wind reduction effect

Rikitake dynamo system, its circuit simulation and chaotic synchronization via quasi-sliding mode control

Rikitake dynamo system (1958) is a famous two-disk dynamo model that is capable of executing nonlinear chaotic oscillations similar to the chaotic oscillations as revealed by palaeomagnetic study. First, we detail the Rikitake dynamo system, its signal plots and important dynamic properties. Then a circuit design using Multisim is carried out for the Rikitake dynamo system. New synchronous quasi-sliding mode control (QSMC) for Rikitake chaotic system is studied in this paper. Furthermore, the selection on switching surface and the existence of QSMC scheme is also designed in this paper. The efficiency of the QSMC scheme is illustrated with MATLAB plots

A novel one-pot synthesis and characterization of silk fibroin/α-calcium sulfate hemihydrate for bone regeneration

Funding Information: Funding: Support for this work was provided by the Ministry of Science and Technology, Taiwan MOST 109-2224-E-038-002. The APC was funded by MOST. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.This study aims to fabricate silk fibroin/calcium sulfate (SF/CS) composites by one-pot synthesis for bone regeneration applications. The SF was harvested from degummed silkworm cocoons, dissolved in a solvent system comprising of calcium chloride:ethanol:water (1:2:8), and then mixed with a stoichiometric amount of sodium sulfate to prepare various SF/CS composites. The crystal pattern, glass transition temperature, and chemical composition of SF/CS samples were analyzed by XRD, DSC, and FTIR, respectively. These characterizations revealed the successful synthesis of pure calcium sulfate dihydrate (CSD) and calcium sulfate hemihydrate (CSH) when it was combined with SF. The thermal analysis through DSC indicated molecular-level interaction between the SF and CS. The FTIR deconvolution spectra demonstrated an increment in the β-sheet content by increasing CS content in the composites. The investigation into the morphology of the composites using SEM revealed the formation of plate-like dihydrate in the pure CS sample, while rod-like structures of α-CSH surrounded by SF in the composites were observed. The compressive strength of the hydrated 10 and 20% SF-incorporated CSH composites portrayed more than a twofold enhancement (statistically significant) in comparison to that of the pure CS samples. Reduced compressive strength was observed upon further increasing the SF content, possibly due to SF agglomeration that restricted its uniform distribution. Therefore, the one-pot synthesized SF/CS composites demonstrated suitable chemical, thermal, and morphological properties. However, additional biological analysis of its potential use as bone substitutes is required.publishersversionPeer reviewe