摘要 :
Aqueous zinc metal batteries (AZMB) are emerging as a promising alternative
to the prevailing existing Lithium-ion battery technology. However, the
development of AZMBs is hindered due to challenges including dendrite
formation...
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Aqueous zinc metal batteries (AZMB) are emerging as a promising alternative
to the prevailing existing Lithium-ion battery technology. However, the
development of AZMBs is hindered due to challenges including dendrite
formation, hydrogen evolution reaction (HER), and ZnO passivation on the
anode. Here, a tetraalkylsulfonamide (TAS) additive for suppressing HER,
dendrite formation, and enhancing cyclability is rationally designed. Only
1 mm TAS is found that can effectively displace water molecules from the
Zn~(2+) solvation shell, thereby altering the solvation matrix of Zn~(2+) and
disrupting the hydrogen bond network of free water, as demonstrated through
~(67) Zn and ~1H nuclear magnetic resonance spectroscopy, high-resolution mass
spectrometry (HRMS), and density functional theory (DFT) studies.
Voltammetry synchronized with in situ monitoring of the electrode surface
reveals suppressed dendritic growth and HER in the presence of TAS.
Electrochemical mass spectrometry (ECMS) captures real-time HER
suppression during Zn electrodeposition, revealing the ability of TAS to
suppress the HER by an order of magnitude. A ≈25-fold cycle life
improvement from ≈100 h to over 2500 h in coin cells cycled in the presence
of TAS. Furthermore, by suppressing passivation product formation, it is
demonstrated that strategy robustly maximizes the stability of Zn metal
anodes.
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Abstract As Japan has abundant annual rainfall (1,000 to 2,500 mm), soil salinity of agricultural lands has rarely been a major problem. Following the 2011 earthquake in the Pacific, large stretches of land along the coast in nort...
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Abstract As Japan has abundant annual rainfall (1,000 to 2,500 mm), soil salinity of agricultural lands has rarely been a major problem. Following the 2011 earthquake in the Pacific, large stretches of land along the coast in northeast Japan were devastated by a powerful tsunami. Saltwater damage of agricultural lands was so severe that agricultural crops could not be grown on large parts of the tsunami-inundated farmlands even two years after the disaster. This paper summarizes the status of agricultural lands in northeast Japan's Tohoku region that were affected by the tsunami. The paper presents the results of a field study of agricultural lands in Miyagi Prefecture, where the extent of the seawater damage was the most severe, representing 67% of the total tsunami-affected agricultural lands. Forty samples from surface and underlying (undisturbed) soil were collected from 30 different locations in coastal and tsunami-inundated farmlands and from inland sites located beyond the limit of the tsunami inundation. The analyses and measurements showed that the extent of soil salinity varied greatly across these sites, with the highest electrical conductivity (EC) value of 3.72 dS m??1 found in the surface soil of Minamisanriku cho. In addition, two study sites adjacent to each other, Watari cho and Yamamoto cho, had maximum and minimum \{EC\} values of 2.0 dS m??1 and 0.21 dS m??1, respectively, in their underlying soils. A comparison of the major soil properties revealed that the salinity status of the tsunami-inundated farmlands was dependent on particle size distribution and therefore on the infiltration rate of the soil, as well as the relative physical position (elevation) of the farmland. This study led us to carry out further investigations and experiments (still on-going) related to restoration and mitigation work in the tsunami-inundated agricultural lands, giving the highest priority to the major soil properties of different field sites in Miyagi Prefecture.
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The design and synthesis of metal-free catalysts with superior electrocatalytic activity, high durability, low cost, and under mild conditions is extremely desirable but remains challenging. To address this problem, a polymer-assi...
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The design and synthesis of metal-free catalysts with superior electrocatalytic activity, high durability, low cost, and under mild conditions is extremely desirable but remains challenging. To address this problem, a polymer-assisted electrochemical exfoliation technique of graphite in the presence of an aqueous acidic medium is reported. This simple, cost-effective, and mass-scale production approach could open the possibility for the synthesis of high-quality nitrogen-doped graphene-polypyrrole (NG-PPy). The NG-PPy catalyst displays an improved half wave potential (E_(1/2)= 0.77 V) in alkaline medium compared with G-PPy (E_(1/2)= 0.66 V). Most importantly, this catalyst demonstrates excellent stability with high methanol tolerance, and it outperforms the commercial Pt/C catalyst and other previously reported metal-free catalysts. The content of graphitic nitrogen atoms is the key factor for the enhancement of electrocatalytic activity towards oxygen reduction reactions (ORR). Interestingly, the NG-PPy catalyst can be used as a cathode material in a zinc-air battery, which demonstrates a higher peak power density (59 mWcm~(-2)) than G-PPy (36.6 mWcm~(-2)), highlighting the importance of the low-cost material synthesis approach towards the development of metal-free efficient ORR catalysts for fuel cell and metal-air battery applications. Remarkably, the polymer-assisted electrophoretic exfoliation of graphite with a high yield (≈88 wt%) of few-layer graphene flakes could pave the way towards the mass production of high-quality graphene for a variety of applications.
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Alow cost solar photovoltaic powered forced draft cook stove was developed and evaluated in the Department of Farm Machinery and Power, OUAT, Bhubaneswar during 2016-17. Performance of the cook stove developed was compared with co...
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Alow cost solar photovoltaic powered forced draft cook stove was developed and evaluated in the Department of Farm Machinery and Power, OUAT, Bhubaneswar during 2016-17. Performance of the cook stove developed was compared with commercially availablenatural draft "Harsha" stove (MNRE approved), modified natural draft "Harsha" stove and traditional mud stove. The cost of the developed set up with solar module and battery was about Rs. 3000/-. It was found that the average cooking efficiency of developed cook stove, "Harsha" stove, modified natural draft "Harsha" stove, and traditional mud stove was 27.63%, 18.86 %, 14.52 % and 9.32 % respectively using unprocessed biomass for boiling of 2 litres of water under water boiling test. The cooking efficiency of solar powered forced draft cook stove under controlled cooking test in boiling rice and potato was in the range of 24-30 %. Percentage saving in cooking time for forced draft cook stove, modified natural draft cook stove and "Harsha" stove compared to traditional stove was 49.71 %, 40.8 %, and 18.28 %, respectively for boiling of 2 litres of water. Similarly, percentage saving in fuel consumption for forced draft cook stove, modified natural draft cook stove and "Harsha" stove compared to traditional stove was 53.7 %, 40.74 % and 20.37 % respectively for boiling of 2 litres of water. Harmful emissions in case of developed stove was also less compared to the other stoves.
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Over the past decade, flexible and wearable microelectronic devices and systems have gained significant importance. Because portable power source is an essential need of such wearable devices, currently there is considerable resea...
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Over the past decade, flexible and wearable microelectronic devices and systems have gained significant importance. Because portable power source is an essential need of such wearable devices, currently there is considerable research emphasis on the development of planar interdigitated micro energy -torage devices by employing diverse precursor materials to obtain functional materials (functional carbon, oxides, etc.) with the desirable set of properties. Herein we report for the first time the use of metal organic framework (MOF) and zeolitic imidazolate framework (ZIF-67) for high-wavelength photothermal laser direct writing of metal-decorated, heteroatom-doped, porous few-layer graphene electrodes for microsupercapacitor application. We argue that the specific attributes of MOF as a precursor and the high-wavelength laser writing approach (which creates extremely high localized and transient temperature (>2500 ℃) due to strong absorption by lattice vibrations) are together responsible for the peculiar interesting properties of the carbon material thus synthesized, thereby rendering extremely high cycling stability to the corresponding microsupercapacitor device. Our device exhibits near 100% retention after 200 000 cycles as well as stability under 150° bending.
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Study was conducted to investigate the power and exhaust emission characteristics of a small diesel engine when fueled by two different kinds of fuels. In this study, light oil, and waste vegetable oil transesterified by ethanol w...
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Study was conducted to investigate the power and exhaust emission characteristics of a small diesel engine when fueled by two different kinds of fuels. In this study, light oil, and waste vegetable oil transesterified by ethanol were used as fuels and engine performances were tested. From the experiments, it became clear that the transesterified oil was more effective particularly in reducing the exhaust emissions than light oil. At the same time, the transesterified oil did not show any inferior performance in the power test to the light oil.
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Experiments were carried out with different plant leaves partially coated with fibrous membrane. The purpose of the study was to investigate the effects of membrane coating on the amount of evapo-transpiration (ET). The results sh...
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Experiments were carried out with different plant leaves partially coated with fibrous membrane. The purpose of the study was to investigate the effects of membrane coating on the amount of evapo-transpiration (ET). The results show that for radish (as a sample of herbaceous plants), when the leaf-surface had coating on it, the amount of ET certainly decreased resulting a total reduction of 11.2%. The effect of the presence or absence of coating on the amount of ET was tested out with 5% significance probability. For rice, in the first half of the growth stage of the plants with coating, the amount of ET showed a tendency to be decreased, however, the amount tended to be increased thereafter. On the other hand, for rose (a sample of woody plants), the amount of ET for plants with coating was less than the amount for the non-coated plants and the tendency continued almost throughout the observation period with 5% significance level.
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The growth of various halophytes in coastal saline soils was compared and the effect of halophytes on changes in chemical properties of saline soils and rehabilitation of coastal saline soils was investigated at the Sirlndhorn Int...
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The growth of various halophytes in coastal saline soils was compared and the effect of halophytes on changes in chemical properties of saline soils and rehabilitation of coastal saline soils was investigated at the Sirlndhorn International Environmental Park, Cha-am district, Petchaburi province between April 2010 and September 2011. The experimental design was a randomized complete block design with 4 replications. The halophyte species were: i) Dixie grass {Sporotxilus virginicus coarse type), ii)Smyrna grass {Sporotmlus wginicus smooth type), Hi) Seabrook grass {DIstichlis spicata), iv) Georgia grass (Spartina patens), and 5) natural grasses. It was found that Dixie grass showed the highest survival rate, followed by Smyrna grass, Georgia grassand Seabrook grass. Seabrook grass had the highest fresh and dry weights of 19,796.25 and 12,178.75 kg ha~(-1), respectively, followed by Georgia grass, Dixie grass and Smyrna grass. Seabrook grass accumulated larger amounts of sodium (Na) than Georgiagrass. Dixie grass and Smyrna grass. The study of the effect of halophytes on soil chemical changes found that in general, soil organic matter, as well as phosphorus and potassium levels, increased, while soil electrical conductivity decreased.
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