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Hydrothermal treatment of pearl millet grains:Effects on nutritional composition,antinutrients and flour properties 被引量:1
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作者 P.Prashanth T.Jayasree Joshi +1 位作者 Shagolshem Mukta Singh P.Srinivasa Rao 《Grain & Oil Science and Technology》 CAS 2024年第2期87-95,共9页
Pearl millet(Pennisetum glaucum)is one of the major millets with high nutritional properties.This crop exhibits exceptional resilience to drought and high temperatures.However,the processing of pearl millet poses a si... Pearl millet(Pennisetum glaucum)is one of the major millets with high nutritional properties.This crop exhibits exceptional resilience to drought and high temperatures.However,the processing of pearl millet poses a significant challenge due to its high lipid content,enzyme activity,and presence of antinutrients.Consequently,it becomes imperative to enhance the quality and prolong the shelf life of pearl millet flour by employing suitable technologies.Hydrothermal treatment in the food industry has long been seen as promising due to its potential to reduce microbial load,inactivate enzymes,and improve nutrient retention.This study aims to investigate the effects of hydrothermal treatment on the quality characteristics of pearl millet.The independent variables of the study were soaking temperature(35,45,55℃),soaking time(2,3,4 h),and steaming time(5,10,15 min).Treatment conditions had a statistically significant effect on nutrient retention.Major antinutrients like tannins and phytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,respectively,after the treatment.Lipase activity decreased significantly up to 10% with the treatment conditions.The findings of this study could potentially encourage the use of pearl millet flour in the production of various food items and promote the application of hydrothermal treatment in the field of food processing. 展开更多
关键词 Pearl millet hydrothermal treatment Nutritional properties ANTINUTRIENTS
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In situ Hydrothermal Oxidation of Ternary FeCoNi Alloy Electrode for Overall Water Splitting 被引量:1
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作者 Yuwei Chen Lixia Yang +4 位作者 Chao Li Yuqiu Wu Xiao Lν Hairen Wang Jun'e Qu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期161-170,共10页
Exploring noble metal-free catalyst materials for high efficient electrochemical water splitting to produce hydrogen is strongly desired for renewable energy development.In this article,a novel bifunctional catalytic ... Exploring noble metal-free catalyst materials for high efficient electrochemical water splitting to produce hydrogen is strongly desired for renewable energy development.In this article,a novel bifunctional catalytic electrode of insitu-grown type for alkaline water splitting based on FeCoNi alloy substrate has been successfully prepared via a facile one-step hydrothermal oxidation route in an alkaline hydrogen peroxide medium.It shows that the matrix alloy with the atom ratio 4∶3∶3 of Fe∶Co∶Ni can obtain the best catalytic performance when hydrothermally treated at 180℃for 18 h in the solution containing 1.8 M hydrogen peroxide and 3.6 M sodium hydroxide.The as-prepared Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode exhibits small overpotentials of only 184 and 175 mV at electrolysis current density of 10 mA cm^(-2)for alkaline OER and HER processes,respectively.The overall water splitting at electrolysis current density of 10 mA cm^(-2)can be stably delivered at a low cell voltage of 1.62 V.These characteristics including the large specific surface area,the high surface nickel content,the abundant catalyst species,the balanced distribution between bivalent and trivalent metal ions,and the strong binding of in-situ naturally growed catalytic layer to matrix are responsible for the prominent catalytic performance of the Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode,which can act as a possible replacement for expensive noble metal-based materials. 展开更多
关键词 alkaline water electrolysis bifunctional electrocatalyst FeCoNi alloy hydrothermal oxidation in-situ growing
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Discovery and characterization of a new hydrothermal field at 2°N on the slow-spreading Carlsberg Ridge
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作者 Zhongyan QIU Yejian WANG +6 位作者 Xiqiu HAN Honglin LI Xing YU Ruyong CUI Mou LI Xuegang CHEN Jiqiang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1106-1118,共13页
A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsber... A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsberg Ridge(CR).Here,the results of two expeditions conducted to detect and characterize the new hydrothermal field are reported.Mineralogical and geochemical data,as well as 14 C ages of a sediment core collected near the field are presented to reveal the hydrothermal history.Results show that the Tianshi field is a basalt-hosted hydrothermal system.Geochemical data of the sediments collected near the field indicate a strong hydrothermal contribution,and hydrothermal Fe and Cu fluxes range from 30 to 155 mg/(cm^(2)·ka)and 0.59 to 11.49 mg/(cm^(2)·ka),respectively.Temporal variations in the fluxes of hydrothermal Fe indicate that there have been at least three amplified hydrothermal venting events(H 1,H 2,and H 3)in the Tianshi field over the last 35.2 ka,in 28.6-35.2 ka BP,22.0-27.6 ka BP,and 1.2-11.4 ka BP,respectively.Hydrothermal event H 2 was driven by an increased magmatic production associated with sea level fall during the Last Glacial Maximum,while event H 3 was promoted by tectonic activity associated with a rapid sea level rise.This study further verified the role of sea level change in modulating hydrothermal activity on mid-ocean ridges. 展开更多
关键词 plume anomaly sediment core new hydrothermal field hydrothermal history Carlsberg Ridge
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Episodic hydrothermal alteration on Middle Permian carbonate reservoirs and its geological significance in southwestern Sichuan Basin,SW China
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作者 FENG Mingyou SHANG Junxin +5 位作者 SHEN Anjiang WEN Long WANG Xingzhi XU Liang LIANG Feng LIU Xiaohong 《Petroleum Exploration and Development》 SCIE 2024年第1期81-96,共16页
To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin,petrology,geochemistry,fluid inclusion and U-Pb dating researches are conducted.The... To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin,petrology,geochemistry,fluid inclusion and U-Pb dating researches are conducted.The fractures and vugs of Middle Permian Qixia–Maokou formations are filled with multi-stage medium-coarse saddle dolomites and associated hydrothermal minerals,which indicates that the early limestone/dolomite episodic alteration was caused by the large-scale,high-temperature,deep magnesium-rich brine along flowing channels such as basement faults or associated fractures under the tectonic compression and napping during the Indosinian.The time of magnesium-rich hydrothermal activity was from the Middle Triassic to the Late Triassic.The siliceous and calcite fillings were triggered by hydrothermal alteration in the Middle and Late Yanshanian Movement and Himalayan Movement.Hydrothermal dolomitization is controlled by fault,hydrothermal property,flowing channel and surrounding rock lithology,which occur as equilibrium effect of porosity and permeability.The thick massive grainstone/dolomites were mainly altered by modification such as hydrothermal dolomitization/recrystallization,brecciation and fracture-vugs filling.Early thin-medium packstones were mainly altered by dissolution and infilling of fracturing,bedding dolomitization,dissolution and associated mineral fillings.The dissolved vugs and fractures are the main reservoir space under hydrothermal conditions,and the connection of dissolved vugs and network fractures is favorable for forming high-quality dolomite reservoir.Hydrothermal dolomite reservoirs are developed within a range of 1 km near faults,with a thickness of 30–60 m.Hydrothermal dolomite reservoirs with local connected pore/vugs and fractures have exploration potential. 展开更多
关键词 Sichuan Basin PERMIAN Middle Permian Qixia Formation Middle Permian Maokou Formation hydrothermal fluid hydrothermal dissolution DOLOMITE
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Hydrothermal hydrogenation/deoxygenation of palmitic acid to alkanes over Ni/activated carbon catalyst
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作者 Min Lin Yuhao Yan +2 位作者 Xiaoxian Li Rui Li Yulong Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期8-18,共11页
To produce paraffin from hydrogenation/deoxygenation of palmitic acid,model compound of bio-oil obtained by hydrothermal liquefaction(HTL)of microalgae has been an attractive focus in recent years.In order to avoid en... To produce paraffin from hydrogenation/deoxygenation of palmitic acid,model compound of bio-oil obtained by hydrothermal liquefaction(HTL)of microalgae has been an attractive focus in recent years.In order to avoid energy-intensive separation process of water and bio-oil,it is of importance that deoxygenation upgrading of fatty acids under hydrothermal conditions similar to HTL process.Herein,it is the first time to explore the application of activated carbon(AC)-supported non-noble-metal catalysts,such as Ni,Co,and Mo,and so on,in the hydrothermal hydrogenation/deoxygenation of long-chain fatty acids,and the obtained Ni/AC-H(the Ni/AC was further H_(2)pre-reduced)is one of the best catalysts.In addition,it is found that the catalytic activity can be further improved by H_(2)pre-reduction of catalyst.Characterization results that are more low valences of nickel and oxygen vacancy can be obtained after H_(2)pre-reduction,thus significant promoting the deoxygenation especially the decarbonylation pathway of fatty acids.The total alkanes yield can reaches 95.9%at optimal conditions(280℃,360 min).This work confirmed that the low-priced AC-supported non-noble-metal catalysts have great potential compared with the noble-metal catalyst,in hydrothermal upgrading of bio-oil. 展开更多
关键词 BIO-OIL Fatty acids DEOXYGENATION hydrothermal upgrading
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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China
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作者 DING Gaoming JI Genyuan +5 位作者 YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期736-752,共17页
Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-di... Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration. 展开更多
关键词 3D geochemical model ore-forming elements GEOSTATISTICS deep mineralization prediction Yechangping Mo deposit
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Cu-Zn isotope compositions of hydrothermal sediments from the southern Mid-Atlantic Ridge:implications to the sediment formation and mineral exploration
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作者 Baoju YANG Lianhua HE +3 位作者 Chuanshun LI Qiannan HU Bingfu JIN Jihua LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1470-1485,共16页
Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples wer... Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples were separated,and Cu and Zn isotope compositions were analyzed.Results show that the ranges ofδ^(65)Cu values of the bulk sediments,sulfides,and oxides were 0.36‰-2.46‰,-0.21‰-1.10‰,and 0.68‰-1.52‰,respectively.Theδ^(65)Cu values of sulfides in four samples(46II-14,46II-30,46III-06,and 46II-09)were relatively low(-0.21‰-0.50‰),corresponding to theδ^(65)Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge(n MAR),suggesting that the sulfides in the sediments were originated from collapsed dead chimney mainly.While theδ^(65)Cu values of the other two samples(46III-02 and 46III-08)were relatively high(1.10‰-0.96‰),corresponding to theδ^(65)Cu values for active hydrothermal chimneys sulfides in n MAR,which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal plume.Because of the high density of sulfide particles,they tended to settle near the hydrothermal vents first.Therefore,highδ^(65)Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal field.Theδ^(66)Zn values of hydrothermal sediments and sulfides ranged 0.11‰-0.43‰and 0.29‰-0.67‰,respectively.In the four samples from the Xunmei hydrothermal field,a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio,showing that the greater the distance from the mineralized spot,the heavier the Zn isotope composition as seen in two samples(46II-30 and 46II-14)of the Xunmei-3 spot.This result aligned with the findings of Wilkinson et al.(2005)and Baumgartner et al.(2023),suggesting that the lower the Zn isotope composition,the closer it is to the hydrothermal vent.However,in the Xunmei hydrothermal field,the Zn isotope composition in the other two samples(46III-02and 46III-06)showed the opposite trend.This indicated that there might be an active hydrothermal vent near the sampling location of sample 46III-02.This observation aligned with the Cu isotope analysis results.This study showed that Cu-Zn isotopes are good indicators for understanding the formation mechanisms of hydrothermal sediments and for locating active hydrothermal vents. 展开更多
关键词 Cu-Zn isotope hydrothermal sediments mineral exploration southern Mid-Atlantic Ridge
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Multi-Component Resource Recycling from Waste Light-Emitting Diode Under Hydrothermal Condition:Plastic Package Degradation,Speciation of Nano-TiO_(2),and Environmental Impact Assessment
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作者 Yongliang Zhang Lu Zhan Zhenming Xu 《Engineering》 SCIE EI CAS CSCD 2024年第8期253-261,共9页
Light emitting diodes(LEDs)have accounted for most of the lighting market as the technology matures and costs continue to reduce.As a new type of e-waste,LED is a double-edged sword,as it contains not only precious an... Light emitting diodes(LEDs)have accounted for most of the lighting market as the technology matures and costs continue to reduce.As a new type of e-waste,LED is a double-edged sword,as it contains not only precious and rare metals but also organic packaging materials.In previous studies,LED recycling focused on recovering precious and strategic metals while ignoring harmful substances such as organic packaging materials.Unlike crushing and other traditional methods,hydrothermal treatment can provide an environment-friendly process for decomposing packaging materials.This work developed a closed reaction vessel,where the degradation rate of plastic polyphthalamide(PPA)was close to 100%,with nano-TiO_(2)encapsulated in plastic PPA being efficiently recovered,while metals contained in LED were also recycled efficiently.Besides,the role of water in plastic PPA degradation that has been overlooked in current studies was explored and speculated in detail in this work.Environmental impact assessment revealed that the proposed recycling route for waste LED could significantly reduce the overall environmental impact compared to the currently published processes.Especially the developed method could reduce more than half the impact of global warming.Furthermore,this research provides a theoretical basis and a promising method for recycling other plastic-packaged e-waste devices,such as integrated circuits. 展开更多
关键词 Waste LED hydrothermal treatment RECYCLING Plastic PPA degradation Packaging materials
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Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis
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作者 Han Dang Runsheng Xu +2 位作者 Jianliang Zhang Mingyong Wang Jinhua Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile con... The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly reduced.The optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization degree.The apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and anthracite.This makes P-HC more suitable for blast furnace injection fuel.Additionally,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion. 展开更多
关键词 blast furnace injection BIOMASS cross-upgrading hydrothermal carbonization PYROLYSIS physicochemical properties gasific-ation properties
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Characterization of Hydroxyapatite Extracted from Crab Shell Using the Hydrothermal Method with Varying Holding Times
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作者 Deni Fajar Fitriyana Rifky Ismail +2 位作者 Athanasius Priharyoto Bayuseno Januar Parlaungan Siregar Tezara Cionita 《Journal of Renewable Materials》 EI CAS 2024年第6期1145-1163,共19页
Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_... Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively. 展开更多
关键词 HYDROXYAPATITE crab shells CaCO_(3) hydrothermal holding time
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Conditions for the enrichment of karst hydrothermal resources in Bohai Bay Basin
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作者 Pengwei Li Zhiliang He +2 位作者 Zongquan Hu Ying Zhang Jianyun Feng 《Energy Geoscience》 EI 2024年第1期172-183,共12页
Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or ... Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or indications of karst reservoirs is inadequate for the exploration of karst hydrothermal resources.This study seeks to elucidate the cause of geothermal sweet spots by analyzing the interplay between geothermal anomalies and karst reservoirs and the underlying geological conditions for karst hydrothermal enrichment.Key findings include:(1)the Bohai Bay Basin has been geologically favorable for the development of karst hydrothermal resources since the Mesozoic era;(2)the karst hydrothermal enrichment varies significantly between the basin’s margin and its interior.On the basin margin,the enrichment is largely driven by groundwater activity and faults,particularly where faults facilitate the upwelling of geothermal water.In contrast,within the basin’s interior,karst hydrothermal resources are predominantly influenced by buried hills and are especially enriched in areas facilitating the discharge of deep geothermal waters. 展开更多
关键词 Buried hill Karst hydrothermal resources Enrichment regularity Bohai bay basin
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Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting
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作者 Yang Sha Menghui Zhu +6 位作者 Kun Huang Yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng Paul Mativenga Zhu Liu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期340-351,共12页
Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring ... Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts.Herein,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE IE-NiMo-LR.This electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·cm-2.During the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially unchanged.In addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water splitting.This combination exhibits excellent durability under industrial current density.The energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal method.The LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production. 展开更多
关键词 electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate
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A Comparison of Hydrothermal Aging, SO2 and Propene Poisoning Effects on NH3-SCR over Cu-ZSM-5 and Cu-SAPO-34 Catalysts
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作者 Kouadio Brou Albert Koffi Konan Martin +1 位作者 Zran Van Eric-Simon Horo Kone 《Journal of Materials Science and Chemical Engineering》 2024年第5期10-28,共19页
This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both... This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both Cu-SAPO-34 and Cu-ZSM-5. The catalytic activities of fresh, aged and poisoned samples were tested in ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) of NO<sub>x</sub> conditions. The XRD, TG and N<sub>2</sub>-desorption results showed that the structures of the Cu-SAPO-34 and Cu-ZSM-5 remained intact after 750˚C hydrothermally aged, SO<sub>2</sub> and propene poisoned. After hydrothermal aging at 750˚C for 12 h, the NO reduction performance of Cu-ZSM-5 was significantly reduced at lower temperatures, while that of Cu-SAPO-34 was less affected. Moreover, Cu-SAPO-34 catalyst showed high NO conversion with SO<sub>2</sub> or propene compared to Cu-ZSM-5. However, Cu-ZSM-5 showed a larger drop in catalytic activity with SO<sub>2</sub> or propene compared to Cu-SAPO-34 catalyst. The H<sub>2</sub>-TPR results showed that Cu<sup>2 </sup> ions could be reduced to Cu<sup> </sup> and Cu<sup>0</sup> for Cu-ZSM-5, while no significant transformation of copper species was observed for Cu-SAPO-34. Meanwhile, the UV-vis DRS results showed that CuO species were formed in Cu-ZSM-5, while little changes were observed for the Cu-SAPO-34. Cu-SAPO-34 showed high sulfur and hydrocarbon poison resistance compared to Cu-ZSM-5. In summary, Cu-SAPO-34 with small-pore zeolite showed higher hydrothermal stability and better hydrocarbon and sulfur poison resistant than Cu-ZSM-5 with medium-pore. 展开更多
关键词 hydrothermal Aging Propene and SO2Poisoning Ammonia-Selective Catalytic Reduction(NH3-SCR) Cu-SAPO-34 CU-ZSM-5
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Simulating Some Complex Phenomena in Hydrothermal Ore-Forming Processes by Reaction-Diffusion CNN 被引量:1
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作者 Xu Deyi Yu Chongwen Bao Zhengyu Geochemistry Institute, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期215-219,共5页
Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients t... Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients transformed from Zhabotinksii model. They revealed somehow the mechanism of hydrothermal ore-forming processes, and answered several questions about the onset of ore forming. 展开更多
关键词 hydrothermal ore forming complexity reaction-diffusion CNN
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Rare-Earth Element Mobility During Ore-Forming Hydrothermal Alteration: A Case Study of Dongping Gold Deposit, Hebei Province, China 被引量:4
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作者 包志伟 赵振华 《Chinese Journal Of Geochemistry》 EI CAS 2003年第1期45-57,共13页
REE mobility during hydrothermal ore-forming processes has been extensively investigated in recent years and the potential of REE to provide information about ore forming processes has commonly been recognized. The Do... REE mobility during hydrothermal ore-forming processes has been extensively investigated in recent years and the potential of REE to provide information about ore forming processes has commonly been recognized. The Dongping gold deposit, which is located in northwestern Hebei Province, China, occurring in the inner contact zone of the Shuiquangou syenite complex, is spatially, and probably genetically, related to the syenite. The deposit was formed under the moderate to high temperature (220℃ to 320℃), weakly acidic to weakly alkaline, rather high f O 2 (lgf O 2=-30 ~- 34) environment. The REE study of the host rocks, altered wall rocks, ores and gangue minerals from the deposit suggests that the REEs have been mobilized and differentiated during K-feldspathization and silicification. The extremely altered syenite enveloping auriferous quartz vein shows positive Ce anomaly and larger LREE/HREE ratio than that of the unaltered syenite. The REE concentrations and patterns of the ores are determined by the ore types and mineral assemblages. LREE/HREE ratios in the gangue quartz and hydrothermal K-feldspars are relatively low. The most significant observation is that the gangue quartz shows significant positive Eu anomaly, whereas the hydrothermal K-feldspars show less significant or no positive Eu anomaly at all relative to the primary feldspar in the unaltered syenite. It is evident that the REEs are mobile during K-feldspathization and silicification in the ore forming process. Weak to moderate K-feldspathization caused REE mobility without apparent differentiation with the exception of extreme K-feldspathization and silicification which resulted in significant depletion of HREE and Eu and relative enrichment of Ce. The REE, Y, U, Th and Au contents of the syenite decrease as the degrees of K-feldspathization and silicification of the rocks increase towards the auriferous quartz veins. As the ores were deposited under a rather oxidized environment, Ce 4+ predominated over Ce 3+. The precipitation of the former in the form of CeO 2 or absorpted onto the secondary mineral assemblage resulted in the inconsistent removal of the REE and the relative Ce enrichment in the strongly altered rocks. In contrast, Eu was present mainly in a low valence state (Eu 2+). The geochemical differences from the other REE 3+ and much less sites in the secondary minerals to accommodate the Eu released from the original minerals resulted in the enrichment of Eu in the fluids. The mobility and differentiation of REE and the coherent mobilities of Y, U, Th and Au also support the argument that the syenite is one of the source rocks for gold mineralization. The REE contents and patterns of the altered rocks enveloping the auriferous quartz vein could be used as a guide for locating ore veins in mineral exploration. 展开更多
关键词 稀土元素迁移率 热液蚀度 金矿化作用 黑花岗石 河北 金矿床
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Onset and Stability of Thermally-Driven Fluid Convection in a Vertical Rock Crack and Their Implication for Hydrothermal Ore-Forming Processes
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作者 Bao ZhengyuChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期43-54,共12页
Dynamic equations controlling the thermally-driven fluid convection in a single rock crack are established in the paper . The critical criteria for the onset of convection in such a configuration are found by linear d... Dynamic equations controlling the thermally-driven fluid convection in a single rock crack are established in the paper . The critical criteria for the onset of convection in such a configuration are found by linear dynamic analysis of the equations and the stability of the convection discussed by nonlinear analysis method . The research demonstrates that the critical Rayleigh number has a magnitude 103. While the Rayleigh number R of real ore-forming fluids exceeds this value , the convection happens , and as R becomes larger , the fluid convection pattern develops from nonequilibrium steady states to double-periodically produced limit cycles and eventually to chaos (turbulences ).The implication of these dynamic analyses for the ore-forming processes of late-magma tic hydrothermal deposits is also discussed in the paper . 展开更多
关键词 thermally -driven fluid onset of convection STABILITY double -diffusive convection dynamics of ore -forming processes hydrothermal deposit .
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MODELING OF THE PALEOGEOTHERMAL FIELD AND ANALYSIS OF THE HEAT SOURCE FOR THE XIANGSHAN URANIUM ORE-FORMING HYDROTHERMALSYSTEM, EAST CHINA
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作者 SUN Zhanxue (East China Geological Institute, Fuzhou, 344000, Jiangxi, China ) 《Geotectonica et Metallogenia》 1996年第Z2期132-139,共8页
Through the finite-element modeling. a quantitative analysis of paleogeothermal evolution after the main volcanic eruption at Cretaceous period for the Xiangshan uranium ore-field. East China. has been presented. Rese... Through the finite-element modeling. a quantitative analysis of paleogeothermal evolution after the main volcanic eruption at Cretaceous period for the Xiangshan uranium ore-field. East China. has been presented. Researches reveal that the energy from the volcanic lava could affect the geothermal field for only three million years after their eruption. and could not provide heat for the Xiangshan uranium ore-foming hydrothermal system because the time gap between the volcanic activities and the uranium mineralizations is longer than 40 million years. The evidences show that the heat energy for the ore-forming system came from anomalously high paleogeothermal gradient in the study area during the mineralization period. 展开更多
关键词 Paleogeotemperature modeling heat source ANALYSIS hydrothermal URANIUM deposit Xiangshan URANIUM ore-field East China
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Breaking the temperature limit of hydrothermal carbonization of lignocellulosic biomass by decoupling temperature and pressure 被引量:4
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作者 Shijie Yu Xiaoxiao Yang +2 位作者 Qinghai Li Yanguo Zhang Hui Zhou 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1216-1227,共12页
Hydrothermal carbonization(HTC) of lignocellulosic biomass is a promising technology for the production of carbon materials with negative carbon emissions. However, the high reaction temperature and energy consumption... Hydrothermal carbonization(HTC) of lignocellulosic biomass is a promising technology for the production of carbon materials with negative carbon emissions. However, the high reaction temperature and energy consumption have limited the development of HTC technology. In conventional batch reactors, the temperature and pressure are typically coupled at saturated states. In this study, a decoupled temperature and pressure hydrothermal(DTPH) reaction system was developed to decrease the temperature of the HTC reaction of lignocellulosic biomass(rice straw and poplar leaves). The properties of hydrochars were analyzed by scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), Raman spectroscopy, X-ray diffraction(XRD), thermogravimetric analyzer(TGA), etc. to propose the reaction mechanism. The results showed that the HTC reaction of lignocellulosic biomass could be realized at a low temperature of 200℃ in the DTPH process, breaking the temperature limit(230℃) in the conventional process. The DTPH method could break the barrier of the crystalline structure of cellulose in the lignocellulosic biomass with high cellulose content, realizing the carbonization of cellulose and hemicellulose with the dehydration, unsaturated bond formation, and aromatization. The produced hydrochar had an appearance of carbon microspheres, with high calorific values, abundant oxygen-containing functional groups, a certain degree of graphitization, and good thermal stability. Cellulose acts not only as a barrier to protect itself and hemicellulose from decomposition, but also as a key precursor for the formation of carbon microspheres. This study shows a promising method for synthesizing carbon materials from lignocellulosic biomass with a carbon-negative effect. 展开更多
关键词 BIOMASS LIGNOCELLULOSE hydrothermal treatment Hydrochar Carbon materials
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Developing super-hydrophobic and corrosion-resistant coating on magnesium-lithium alloy via one-step hydrothermal processing 被引量:5
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作者 Guowei Wang Dan Song +5 位作者 Yanxin Qiao Jiangbo Cheng Huan Liu Jinghua Jiang Aibin Ma Xiaolong Ma 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第4期1422-1439,共18页
Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys.However,it remains a grand challenge to produce such coatings for magnesium-lithium allo... Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys.However,it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity.Herein,a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium,which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating.The multiscale microstructures with nanoscale stacks and microscale spheres on the surface,as well as the through-thickness stearates,lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating. 展开更多
关键词 Magnesium-lithium alloy Super-hydrophobic coating One-step hydrothermal process Corrosion resistance Multiscale microstructure
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Hydrothermal Systems Characterized by Crustal Thermally-dominated Structures of Southeastern China 被引量:3
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作者 WANG Guiling GAN Haonan +5 位作者 LIN Wenjing YUE Gaofan YAN Xiaoxue LI Tingxin ZHANG Wei MA Feng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1003-1013,共11页
Southeastern China(SE China)is located in the Pacific tectonic domain and has experienced a series of tectono-magmatic events induced by the subduction of the Paleo-Pacific Plate since the late Mesozoic.The subduction... Southeastern China(SE China)is located in the Pacific tectonic domain and has experienced a series of tectono-magmatic events induced by the subduction of the Paleo-Pacific Plate since the late Mesozoic.The subduction formed a series of NE-NNE oriented faults under a NW-SE regional stress field,along which a number of thermal springs occur.Previous studies have focused on the genesis mechanism of specific geothermal fields in SE China,but the general characteristics of hydrothermal systems in SE China remains unclear.In this study,we investigate the correlation between geothermal activity,hydrochemical type and regional faults by studying the distribution of hydrothermal activity and geochemical properties of typical hydrothermal systems in SE China.The hydrothermal systems in SE China have a crustal thermally-dominated structural origin unique to the specific geological and tectonic conditions of the Eurasian Plate margin.The upwelling of the asthenosphere and the widespread granitoids with high radiogenic heat production in SE China provide major heat sources for regional geothermal anomalies.The NE-oriented crustal thermally-dominated faults are critical for the formation of geothermal anomalies and NW-oriented extensional faults have created favorable conditions for meteoric water infiltration,transportation and the formation of thermal springs. 展开更多
关键词 hydrothermal system geothermal reservoir geothermal activity thermal lithosphere Southeastern China
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