scholarly journals Removing Nutrients from Crab-Breeding Wastewater by a Floating Plant–Effective Microorganism Bed

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3384
Author(s):  
Lina Chen ◽  
Hong Ling ◽  
Junyi Tan ◽  
Xiaohou Shao
Keyword(s):  
Treatment Effect ◽  
Processing System ◽  
Coverage Rate ◽  
Hydraulic Loading ◽  
Plant Coverage ◽  
In Situ Conditions ◽  
Aquaculture Wastewater ◽  
Effective Microorganism ◽  
Floating Plant

Effective microorganism treatment, a low-cost and remediation measure that with no secondary pollution, was conducted in aquaculture wastewater. Unfortunately, effective microorganism erosion caused by the momentum of water flow under in situ conditions limits the treatment effect. In the channel test, a floating plant bed coupled with the effective microorganism was used to treat crab-breeding wastewater. This study explored the effect of plant coverage and hydraulic loading on aquaculture wastewater purification in the floating plant bed–effective microorganism coupled system. The results show that the effect of the coupled treatment effect is much better than pure microorganism treatment. The pollutant degradation coefficient has a significantly positive correlation with the length of the floating plant bed. A plant coverage rate of 30% and effluent hydraulic loading of 1.0 m3/m2·day are optimum floating plant bed–effective microorganism test conditions. Once the coverage rate exceeded 30%, the increase in the CODMn removal efficiency was not clear. At the same time, the high plant coverage inhibited the oxygen capacity in the water body, which directly led to a decrease in the degradation ability of organic matter by the plant. The biology–ecology coupled technology proposed in this study overcame the shortcomings of the easy-to-lose effective microorganism during the traditional unfixed process and improved the stability of the processing system. It strengthened the crab-breeding wastewater remediation effect. For an in situ application, the artificial restoration system 1 km in length was efficient, and the discharge met the standard at the end of the river.

scholarly journals Rock Surface Fungi in Deep Continental Biosphere—Exploration of Microbial Community Formation with Subsurface In Situ Biofilm Trap

2020 ◽  
Vol 9 (1) ◽  
pp. 64
Author(s):  
Maija Nuppunen-Puputti ◽  
Riikka Kietäväinen ◽  
Lotta Purkamo ◽  
Pauliina Rajala ◽  
Merja Itävaara ◽  
...  
Keyword(s):  
Significant Proportion ◽  
Debaryomyces Hansenii ◽  
Fungal Communities ◽  
Fungal Colonization ◽  
Rock Surface ◽  
Mica Schist ◽  
Deep Subsurface ◽  
Bacterial Phyla ◽  
In Situ Conditions

Fungi have an important role in nutrient cycling in most ecosystems on Earth, yet their ecology and functionality in deep continental subsurface remain unknown. Here, we report the first observations of active fungal colonization of mica schist in the deep continental biosphere and the ability of deep subsurface fungi to attach to rock surfaces under in situ conditions in groundwater at 500 and 967 m depth in Precambrian bedrock. We present an in situ subsurface biofilm trap, designed to reveal sessile microbial communities on rock surface in deep continental groundwater, using Outokumpu Deep Drill Hole, in eastern Finland, as a test site. The observed fungal phyla in Outokumpu subsurface were Basidiomycota, Ascomycota, and Mortierellomycota. In addition, significant proportion of the community represented unclassified Fungi. Sessile fungal communities on mica schist surfaces differed from the planktic fungal communities. The main bacterial phyla were Firmicutes, Proteobacteria, and Actinobacteriota. Biofilm formation on rock surfaces is a slow process and our results indicate that fungal and bacterial communities dominate the early surface attachment process, when pristine mineral surfaces are exposed to deep subsurface ecosystems. Various fungi showed statistically significant cross-kingdom correlation with both thiosulfate and sulfate reducing bacteria, e.g., SRB2 with fungi Debaryomyces hansenii.

scholarly journals Discrete element analysis of the punching behaviour of a secured drapery system: from laboratory characterization to idealized in situ conditions

2021 ◽  
Author(s):  
Antonio Pol ◽  
Fabio Gabrieli ◽  
Lorenzo Brezzi
Keyword(s):  
Mechanical Response ◽  
Steel Wire ◽  
Discrete Element ◽  
Wire Mesh ◽  
Steel Plates ◽  
Loading Conditions ◽  
Element Analysis ◽  
In Situ Conditions ◽  
Wire Meshes

AbstractIn this work, the mechanical response of a steel wire mesh panel against a punching load is studied starting from laboratory test conditions and extending the results to field applications. Wire meshes anchored with bolts and steel plates are extensively used in rockfall protection and slope stabilization. Their performances are evaluated through laboratory tests, but the mechanical constraints, the geometry and the loading conditions may strongly differ from the in situ conditions leading to incorrect estimations of the strength of the mesh. In this work, the discrete element method is used to simulate a wire mesh. After validation of the numerical mesh model against experimental data, the punching behaviour of an anchored mesh panel is investigated in order to obtain a more realistic characterization of the mesh mechanical response in field conditions. The dimension of the punching element, its position, the anchor plate size and the anchor spacing are varied, providing analytical relationships able to predict the panel response in different loading conditions. Furthermore, the mesh panel aspect ratio is analysed showing the existence of an optimal value. The results of this study can provide useful information to practitioners for designing secured drapery systems, as well as for the assessment of their safety conditions.

Plant-based versus metal-based coagulants in aquaculture wastewater treatment: Effect of mass ratio and settling time

2021 ◽  
Vol 43 ◽  
pp. 102269
Author(s):  
Azmi Ahmad ◽  
Siti Rozaimah Sheikh Abdullah ◽  
Hassimi Abu Hasan ◽  
Ahmad Razi Othman ◽  
Nur 'Izzati Ismail
Keyword(s):  
Wastewater Treatment ◽  
Treatment Effect ◽  
Settling Time ◽  
Mass Ratio ◽  
Aquaculture Wastewater

scholarly journals Relating Induced in Situ Conditions of Raw Chicken Breast Meat to Pinking

2004 ◽  
Vol 83 (1) ◽  
pp. 109-118 ◽  
Author(s):  
K. Holownia ◽  
M.S. Chinnan ◽  
A.E. Reynolds ◽  
JW Davis
Keyword(s):  
Chicken Breast ◽  
Breast Meat ◽  
In Situ Conditions ◽  
Chicken Breast Meat

scholarly journals A microscopic approach to investigate bacteria under in situ conditions in sea-ice samples

2001 ◽  
Vol 33 ◽  
pp. 304-310 ◽  
Author(s):  
Karen Junge ◽  
Christopher Krembs ◽  
Jody Deming ◽  
Aaron Stierle ◽  
Hajo Eicken
Keyword(s):  
Sea Ice ◽  
Pore Space ◽  
Three Dimensional ◽  
Epifluorescence Microscopy ◽  
Microbial Populations ◽  
Microbial Life ◽  
Dimensional Network ◽  
In Situ Conditions ◽  
Fluorescent Stain

AbstractMicrobial populations and activity within sea ice have been well described based on bulk measurements from melted sea-ice samples. However, melting destroys the micro-environments within the ice matrix and does not allow for examination of microbial populations at a spatial scale relevant to the organism. Here, we describe the development of a new method allowing for microscopic observations of bacteria localized within the three-dimensional network of brine inclusions in sea ice under in situ conditions. Conventional bacterial staining procedures, using the DNA-specific fluorescent stain DAPI, epifluorescence microscopy and image analysis, were adapted to examine bacteria and their associations with various surfaces within microtomed sections of sea ice at temperatures from −2° to −15°C. The utility and sensitivity of the method were demonstrated by analyzing artificial sea-ice preparations of decimal dilutions of a known bacterial culture. When applied to natural, particle-rich sea ice, the method allowed distinction between bacteria and particles at high magnification. At lower magnifications, observations of bacteria could be combined with those of other organisms and with morphology and particle content of the pore space. The method described here may ultimately aid in discerning constraints on microbial life at extremely low temperatures.

Trial applications at gymnasiums of in-situ sound absorption measurement method by ensemble averaging technique

2021 ◽  
Vol 263 (2) ◽  
pp. 4532-4537
Author(s):  
Toru Otsuru ◽  
Reiji Tomiku ◽  
Noriko Okamoto ◽  
Siwat Lawanwadeekul
Keyword(s):  
Measurement Method ◽  
Sound Absorption ◽  
Glass Wool ◽  
Absorption Measurement ◽  
Ensemble Averaging ◽  
Averaging Technique ◽  
In Situ Conditions ◽  
Measurement Consistency ◽  
Absorption Characteristics

The authors have been published a series of papers on a measurement method for sound absorption characteristics of materials using ensemble averaging technique, i.e., EA method. The papers' results included measurement mechanisms, measurement uncertainty, and so on. Herein, to examine adaptability, especially in in-situ conditions, the EA method is applied to measure absorption characteristics of materials installed in two gymnasiums. A glass-wool panel with the dimension of 0.5 m by 0.5 m by 0.05 m and with the density of 32 kg m^-3 was brought around and measured to check the measurement consistency. Several measurements were conducted during badminton plays were undergoing. Measured sound absorption coefficients revealed that most results agree well with those measured in reverberation rooms. Certain improvement is necessary for the specimen brought to the in-situ measurement to keep the consistency. The inconsistency is considered to originate from unstable conditions between the specimen and floor.

Mechanics of Geological Materials

1985 ◽  
Vol 38 (10) ◽  
pp. 1256-1260 ◽  
Author(s):  
M. M. Carroll
Keyword(s):  
Solid Mechanics ◽  
Oil And Gas ◽  
Rock Fracture ◽  
Energy Resource ◽  
Earthquake Hazard ◽  
Soil Liquefaction ◽  
Failure Behavior ◽  
Geological Materials ◽  
In Situ Conditions

Needed advances in various areas of energy resource recovery, underground construction, earthquake hazard reduction, and conventional and nuclear defense depend critically on the development of improved theories for mechanical and thermal behavior of geological materials. The areas include oil and gas (including off-shore and Arctic production), mining and in situ recovery, geothermal production, nuclear waste isolation, under-ocean tunneling, underground storage, nuclear test containment, and effects of surface explosions. The needed developments, some of which are detailed in earlier National Academy of Science reports, include constitutive theories for inelastic deformation, failure, and post-failure behavior, influence of microstructure and macrostructure, rock fracture (direct breakage, hydraulic fracture explosive fracture), frictional sliding, soil liquefaction, mechanics of ice, determination of in situ conditions, flow through porous media, and thermal effects. Advances in mechanics of geological materials will require adaptation of some established techniques in rheology, metal plasticity, composite materials, mixtures, etc., and also the development of some entirely new ideas and methods. The complicated nature of rocks and soils, the wide ranges of stress, temperature, strain rate, etc., the interactions encountered in geotechnical processes, and the vastly different dimensions and time scales involved, lead to a host of challenging problems in solid mechanics.

Dynamic Impact Measurements on Crossings, in Free Floating and In-Situ Conditions

2014 ◽  
Author(s):  
M. A. Boogaard ◽  
A. L. Schwab ◽  
Z. Li
Keyword(s):  
Finite Element ◽  
Condition Monitoring ◽  
Impact Loading ◽  
Dynamic Behaviour ◽  
Element Model ◽  
Mode Shapes ◽  
Dynamic Impact ◽  
In Situ Test ◽  
In Situ Conditions

As vibration based condition monitoring requires a good understanding of the dynamic behaviour of the structure, a good model is needed. At the TU Delft a train borne monitoring system is being developed which currently focusses on crossings. Crossings are prone to very fast degradation due to impact loading. In this paper a finite element model of a free floating frog is presented and validated up to a 100 Hz using dynamic impact measurements. The mode shapes of the free floating frog are then also compared to some preliminary results from an in-situ test. This comparison shows that the in-situ frequencies can be up to twice the free floating frequency.

scholarly journals The optimization of pressure controller for deep earth drilling

2019 ◽  
Vol 23 (Suppl. 3) ◽  
pp. 877-885 ◽  
Author(s):  
Zhi He ◽  
Ling Chen ◽  
Tong Lu ◽  
Jing Xie
Keyword(s):  
Contact Surface ◽  
The Finite Element Method ◽  
Spherical Contact ◽  
The Earth ◽  
In Situ Conditions ◽  
Strength Material ◽  
Pressure Controller ◽  
Optimization Schemes ◽  
Deep Exploration

Obtaining samples of deep in-situ conditions is first step to explore the mysteries of the earth requires. In view of the current problems of insufficient pressure maintaining capacity of the existing equipment, we independently developed the in-situ fidelity coring system and designed the osmotic pressure controller based on the geometry of square cover. The finite element method is used to analyze the pressure maintaining capacity of the pressure controller. It is found that it would produce large deformation and stress concentration when the pressure was applied on, resulting in low pressure maintaining capacity. Then the structural optimization schemes of conical sealing contact surfaces with 25?, 35?, 40?, and 45? apex angles and spherical sealing contact surface are proposed, and the spherical contact surface structure is found to be optimal. Finally, the material is optimized, and a higher strength material such as 45CrNiMoVA alloy is used. Based on the pressure controller with spherical contact surface, the pressure maintaining capacity increased to nearly 70 MPa. The research results obtained in this paper provide the basis for the development of the coring system, the deep exploration of the earth and the establishment of rock mechanics theory.

scholarly journals Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

2013 ◽  
Vol 10 (9) ◽  
pp. 14595-14626 ◽  
Author(s):  
A. Canion ◽  
J. E. Kostka ◽  
T. M. Gihring ◽  
M. Huettel ◽  
J. E. E. van Beusekom ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Marine Sediments ◽  
Metabolic Response ◽  
Anammox Bacteria ◽  
Advective Flow ◽  
Permeable Sediments ◽  
N Removal ◽  
In Situ Conditions ◽  
Wide Range

Abstract. Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from −5 to 23 °C. Total N2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 μmol N m−2 d−1. For the majority of sites studied, N2 removal was 2 to 7 times more rapid under advective flow conditions. Anammox comprised 6 to 14% of total N2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of −1 to 42 °C. The highest optimum temperature (Topt) for denitrification was 36 °C and was observed in subtropical sediments, while the lowest Topt of 21 °C was observed at the polar site. Seasonal variation in the Topt was observed at the temperate site with values of 26 and 34 °C in winter and summer, respectively. The Topt values for anammox were 9 and 26 °C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. To our knowledge, we provide the first rates of denitrification and anammox from permeable sediments of a polar permanently cold ecosystem. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N removal is highly dependent on community structure.

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