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Author(s):  
Nabeel Kadhim Abbood ◽  
Abdolrahman obeidavi ◽  
Seyednooroldin Hosseini

AbstractIn the current study, the effect of CuO nanoparticles (CuO-NPs) at the presence of dodecyl-3-methylimidazolium chloride ([C12mim][Cl]) is investigated on the interfacial tension (IFT) reduction, wettability alteration, and even tertiary oil recovery. Since the prepared solutions with CuO-NPs are completely dark and it is impossible to measure the IFT of these solutions in the presence of crude oil using the pendant drop method (since one of the phases must be transparent for IFT measurement using the pendant drop method), n-heptane (representative of saturates) and toluene (representative of aromatics) are used only for IFT measurement of solutions prepared by CuO-NPs, while rest of the experiments are performed using crude oil. The obtained results reveal that CuO-NPs are not stable in the aqueous solution in the absence of surfactant which means fast precipitation of CuO-NPs and a high risk of pore plugging. In this way, the stability of CuO-NPs is investigated at the presence of dodecyl-3-methyl imidazolium chloride ([C12mim][Cl]) as an effective surfactant for stabilizing the CuO-NPs in the aqueous solution (more than 1 month without precipitation using 1000 ppm of IL). Further measurements reveal that although the presence of IL in the aqueous solution can reduce the IFT of oil/aqueous solution system, especially for the aqueous solutions prepared by formation brine (0.65 mN.m−1), the presence of CuO-NPs has no considerable effect on the IFT. On the other hand, not only the contact angle (CA) measurements reveal the considerable effect of IL on the wettability alteration toward water-wet condition (68.3° for IL concentration of 1000 ppm) but also the addition of CuO-NPs can significantly boost the wettability alteration toward strongly water-wet condition (23.4° for the concentration of 1000 ppm of CuO-NPs). Finally, several core flooding experiments are performed using different combinations of chemicals to find the effect of these chemicals on the tertiary oil recovery factor. The results reveal that the presence of CuO-NPs can enhance the oil recovery of injected chemical slug (aqueous solution prepared by dissolution of IL with an oil recovery factor of 10.1% based on Original oil in place (OOIP)) to 13.8, %, 16.9%, and 21.2% based on OOIP if 500, 1000, 2000 ppm of CuO-NPs existed in the solution concomitant with 1000 ppm of [C12mim][Cl].


2021 ◽  
Vol 39 (4) ◽  
pp. 138-142
Author(s):  
Ping Kong

Abstract Survival of Burkholderia cepacia complex (Bcc)-based biocontrol agents (BCA) has been associated with their field performance for foliage disease control. SSG, a strain of boxwood endophytic Bcc, suppresses a broad spectrum of plant foliage diseases, including boxwood blight, but the control efficacy declines over time. Factors affecting SSG survival on leaf surfaces were investigated to promote the application of the BCA for boxwood blight management. ‘Justin Brouwers' boxwood plants were treated with SSG cells at 107 to 108 colony-forming unit (CFU)·ml−1, maintained in a moist chamber at 10, 20, or 30 C (50, 68, 86 F), and sampled after the inoculum was blow-dried at 0, 3, 6, 12, and 24 h after treatment. The retained cells per leaf at 0 hours was 105 to 106 CFU, but only less than 10% of the cells survived 24 h after application, irrespective of the wet period and temperature. A wet condition of 12 and 24 h at 20 and 30 C facilitated SSG survival on the second day. Further survival of SSG was affected by temperature but not wetness. Damp conditions and pleasant temperatures can improve bacteria survival and stability and are keys to promoting BCA field applications. Index words: Biocontrol agent, endophyte, survival on plant surfaces, temperature, wetness. Species used in this study: Bacterium strain, SSG (Burkholderia sp);Plant species: Buxus sempervirens L. ‘Justin Brouwers'.


2021 ◽  
Vol 1202 (1) ◽  
pp. 012033
Author(s):  
Gernot Sauter ◽  
Marcel Doring ◽  
Rik Nuyttens

Abstract It is well known that camera and video sensors have limitations in detecting pavement markings under certain conditions e.g. glare from sunlight or other vehicles, rain, fog etc. First generations of lane keeping systems depend on visual light. Erroneous detection is also resulting from irregular road surfaces such as glossy bitumen sealing strips, rain puddles or simply worn asphalt. The role of higher performing markings and better visual camera detection has been studied with Vedecom France. LiDAR (light detection and ranging) technology could help to fill remaining gaps, as it actively sends out IR (infrared) light, that returns reliable images of the road scenario and pavement markings both day and nighttime. In order to evaluate the opportunities of LiDAR technology for the detection of road markings, 3M Company and the University of Applied Sciences in Dresden decided to work together in a joint research project. All-Weather Elements AWE, are the latest development of high-performance optics, using high index beads to provide reflectivity both in dry and wet condition. It could be determined that high performance markings help to increase the level of detection by both camera and LiDAR sensors. The AWE marking was detected from significantly longer distances, especially in wet and rainy conditions. In combination with common camera based LKA and LDW systems, the LiDAR sensors can increase the overall detection rate of pavement markings. This is especially important for vehicles with higher SAE levels of automated driving and can support the overall safety of vehicles. The research also evaluated existing test methods for wet and rain reflectivity in EN 1436 and ASTM E 2832 and how measured performance correlates with LiDAR detection.


2021 ◽  
Vol 9 ◽  
Author(s):  
Hotaek Park ◽  
Alexander N. Fedorov ◽  
Pavel Konstantinov ◽  
Tetsuya Hiyama

Excess ice that exists in forms such as ice lenses and wedges in permafrost soils is vulnerable to climate warming. Here, we incorporated a simple representation of excess ice in a coupled hydrological and biogeochemical model (CHANGE) to assess how excess ice affects permafrost thaw and associated hydrologic responses, and possible impacts on carbon dioxide and methane (CH4) fluxes. The model was used to simulate a moss-covered tundra site in northeastern Siberia with various vertical initializations of excess ice under a future warming climate scenario. Simulations revealed that the warming climate induced deepening of the active layer thickness (ALT) and higher vegetation productivity and heterotrophic respiration from permafrost soil. Meanwhile, excess ice temporarily constrained ALT deepening and thermally stabilized permafrost because of the highest latent heat effect obtained under these conditions. These effects were large under conditions of high excess ice content distributed in deeper soil layers, especially when covered by moss and thinner snow. Once ALT reached to the layer of excess ice, it was abruptly melted, leading to ground surface subsidence over 15–20 years. The excess ice meltwater caused deeper soil to wet and contributed to talik formation. The anaerobic wet condition was effective to high CH4 emissions. However, as the excess ice meltwater was connected to the subsurface flow, the resultant lower water table limited the CH4 efflux. These results provide insights for interactions between warming climate, permafrost excess ice, and carbon and CH4 fluxes in well-drained conditions.


2021 ◽  
Author(s):  
Jinju Zhang ◽  
Fangqing Ge ◽  
Jialing Tan ◽  
Yunjie Yin ◽  
Chaoxia Wang

Abstract Hydrochromic materials has been a novel topic in the research of stimuli-responsive sensors and anticounterfeiting encryption. A high-performance hydrochromic cotton fabric is fabricated with CoCl2/waterborne polyurethane via hot-press method. Moisture sensing metal salt cobalt chloride is introduced into waterborne polyurethane via physical doping to induce hydrochromic phenomenon. The hydrochromic cotton fabric possess superior fastness due to the hydrogen bonds formed by hydroxyl group on cotton fabric and carbonyl group, urethane bond, ether bond in waterborne polyurethane. Meanwhile, the hydroxyl group on cotton fabric and waterborne polyurethane endow hydrochromic cotton fabric with excellent hydrophilicity and high humidity sensitivity. Air humidity could be easily detected by hydrochromic cotton fabric. The absorption of humidity in rainy days led to pink color, resulting in a blue shift at 512 nm. In contrast, hydrochromic cotton fabric turn to blue color below RH 59% in sunny days, leading to a red shift for up to 674 nm. Moreover, the hydrochromic cotton fabric exhibited eminent stability and cyclicity in response to either dry state or wet condition. Based on these excellent properties, hydrochromic cotton fabric fabricated with CoCl2/waterborne polyurethane are promising as smart sensors with potential application in sensitive RH detector, anti-counterfeiting technology and decorative coatings.


Author(s):  
G. Senthil Kumar ◽  
C.R. Chinnamuthu ◽  
R. Mahender Kumar

Background: Wet direct seeding technique in rice, which aims to realize labour saving in paddy rice cultivation, has continued to gain popularity in recent years. Because the work of raising and transplanting seedlings can be omitted, wet direct seeding can make an important contribution to labour saving. In wet DSR, iron coated seed that is, seed is coated with iron powder, which increases its weight so that seed settle easily in water and forms a tough coating that preventing birds from eating the seeds. Methods: Studies were conducted during the year 2018 and 2019 at the Department of Rice, TNAU, Coimbatore on influence of iron coated seeds and time of sowing in wet direct seeded rice. Experiment was laid out in split plot design with three replications. In main plot, different time of sowing at weekly interval viz., first, second, third and fourth week of August sowing, where as in sub-plot iron coated seeds broadcasting in 1-2 mm water level condition; iron coated seeds broadcasting in wet condition; uncoated seeds broadcasting in 1-2 mm water level condition; uncoated seeds broadcasting in wet condition and normal method of transplanting. Result: The results indicated that iron coated seeds of variety Swarna, broadcasting in 1-2 mm water level condition during the first fortnight of August sowing resulted higher grain yield (5653 kg/ha) when compared delayed sowing. The Fe coating significantly increased grain yield over non-coating. Iron coated seeds recorded lesser occurrence of pest and disese incidence when compared to un-coated seeds.


2021 ◽  
Vol 9 (07) ◽  
pp. 21-35
Author(s):  
Md Mizanur Rahman ◽  
◽  
Mohammed Masum ◽  

A detail geological investigation was carried out in order to explore white clay deposite at 10 square kilometer areas of Madhabpur and 0.5 square kilometer areas of Bahubal Upazilas in Habiganj District of Bangladesh using hand auger and shallow drilling method. The whole surveyed area was identified for white clay deposits from qualitative as well as quantitative aspect. These deposits were marked at depths from 0.2 meter to 8.0 meter below the surface. Average thickness of white clay at Madhabpur and Bahubol area are 4.0 meter and 5.0 meter, respectively. The estimated reserve of white clay at Madhabpur area is about 68 million tons and that at Bahubal area is 2.8 million tons. Geological investigation suggests that the source rock near Tripura ranges was weathered, transported and deposited as feldspathic sandstone surrounding the present deposition of white clay. Later the sandstone was exposed and much of its feldspar content were weathered to the clay mineral (Kaolinite). Along with white clay peat, peaty clay, sticky clay and silica sand were also observed at depths ranging from 1.5 to 8 meter. Collected white clay samples are yellowish grey to light grey in color and highly compact in dry condition but pasty in wet condition. The dry white clay is soapy to feel, slakes in water, moderately sticky and plastic in nature. Al2O3 content ranged from 25.51 to 27.61% while average SiO2, and Fe2O3 content were found 54.58 and 3.872% respectively. Considering the physical and chemical properties the white clay of the studied area can be considered as moderate to good in quality. This white clay can use in ceramics and other industries. Therefore, this deposit of white clay may help to meet the current national demand and consequently to increase the economic growth.


2021 ◽  
Vol 13 (SI) ◽  
pp. 198-202
Author(s):  
P. Ramamoorthy ◽  
P. Christy Nirmala Mary

Soil is an important source of human life and agricultural production. Studying on the pedon and its site characteristics pave the way for understanding the nature of soils and its utility. A study on pedological characterization of soils in Melur block, Madurai District (Tamil Nadu), was carried out during 2019-2020 using grid sampling with village map/cadastral maps. Soil mapping unit-based soil samples were collected in Chunampoor, Thuvarangulam, Poonjuthi and Veppapadupu and pedons were characterized as per the standard procedure. The results showed that soils were moderately deep to very deep in nature, ranging from 2.5 YR  3/6 to 10YR 4/6. The soil texture varied from sandy clay loam to sandy clay with weak to moderate sub-angular blocky structure. The consistency of soil varied from slightly hard to very hard when dry, very friable to firm when moist, slightly sticky to very sticky and slightly plastic to very plastic in wet condition. The crops viz., paddy, sugarcane, banana, groundnut and vegetables were very suitable for such type of soil of the Madurai district.


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