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Activity patterns and resource partitioning: seven species at watering sites in the Altun Mountains, China 被引量:4
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作者 XUE Yadong LI Jia +3 位作者 SAGEN Guli ZHANG Yu DAI Yunchuan LI Diqiang 《Journal of Arid Land》 SCIE CSCD 2018年第6期959-967,共9页
As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of th... As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of the Altun Mountains in western China. Information on activity patterns of the wild bactrian camel (Camelus ferus), kiang (Equus kiang), goitered gazelle (Gazella subgutturosa), argali (Ovis ammon), blue sheep (Pseudois nayaur), red fox (Vulpes vulpes), and wolf (Canis lupus) was obtained. We found that the wild camel, kiang, goitered gazelle, argali, and blue sheep were predominantly diurnal at watering sites, whereas red fox and wolf were nocturnal. Five herbivores partitioned the use of watering sites in a temporal manner to minimize the risk of predation by carnivores. The wild camel was the dominant herbivorous species at the watering sites. The kiang, goitered gazelle, argali, and blue sheep displayed adaptive water use by altering spatial or temporal patterns based on the presence or absence of wild camel, to minimize the risk of interspecific strife. These results are suggestive of the differences in activity patterns that might modulate water partitioning by different species, and provide insights for the development of conservation strategies for integrated species and decisions regarding water development in the Altun Mountains. 展开更多
关键词 camera trapping COMPETITION desert animal interaction watering site niche partitioning
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A Computer Program for Automatic Watering Based on Potential Evapotranspiration by Penman Method and Predicted Leaf Area in Miniature Pot Rose Production 被引量:2
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作者 YU Wen-jin Kitamura Ryo +2 位作者 Kato Katsuhiko LI Lian-hua Fukui Hirokazu 《Agricultural Sciences in China》 CAS CSCD 2010年第3期370-377,共8页
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multi... In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production. 展开更多
关键词 automatic watering leaf area miniature pot rose Penman Method program
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The Stimulating Effects of Rewatering on Leaf Area of Winter Wheat Suffering Water Stress 被引量:1
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作者 LIU Xiao-ying, LUO Yuan-pei and SHI Yuan-chun( Institute of Resources and Environments , China Agricultural University, Beijing 100094 Institute of Agrometeorology, CAAS , Beijing 100081) 《Agricultural Sciences in China》 CAS CSCD 2002年第2期177-183,共7页
After water stress at various levels and durations at different growth stages, rewatering could greatly stimulate the leaf area development of winter wheat. The results showed that the stimulation effect changed with ... After water stress at various levels and durations at different growth stages, rewatering could greatly stimulate the leaf area development of winter wheat. The results showed that the stimulation effect changed with water stress time, degree and duration. Rewatering under earlier stress had greater stimulation effect on leaf area than that under later stress. Higher stimulation effect was observed under severe water stress than that under moderate stress. Longer duration of stress resulted in low stimulation effect. In spite of the greater stimulation effect under severe and longer stress, the final leaf area in these situations was lower than that under moderate stress and shorter duration. Whenever the stress occurred, the stimulating effect was due to the increase of the leaf area of the tillers. Once the leaf on the main stem emerged during stress period, rewatering had no effect on its size, and consequently its leaf area. The stimulation of rewateirng on leaf area contributed to the final grain yield by 45% under moderate stress, and 67% under severe stress. Although the stimulation partly compensated for the loss during stress, the final leaf area and the grain yield could not reach the level without water stress. 展开更多
关键词 Water stress REwatering Winter wheat STIMULATION Leaf area YIELD
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Physico-Chemical and Bacteriological Quality of the Vegetable Watering Water in the Dschang Town, Cameroon 被引量:1
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作者 Ntangmo Tsafack Honorine Temgoua Emile Njine Thomas 《Journal of Environmental Protection》 2012年第8期949-955,共7页
Market gardening, in the swampy lowlands of the Dschangcity, plays an important role in terms of providing employment, and supply the city with fresh products. However, waterborne diseases, which occur in the city, ar... Market gardening, in the swampy lowlands of the Dschangcity, plays an important role in terms of providing employment, and supply the city with fresh products. However, waterborne diseases, which occur in the city, are both attributed to the bad quality of drinking water and sanitation practices. This work aims to characterize watering waters of crop, to assess the health risks associated with the use of these waters. Water from eleven streams and five wells used to irrigate crops were sampled and analyzed once a week for a month. Analyses focused on physico-chemical parameters (temperature, suspended matter, pH, electrical conductivity, COD, BOD5, NO-3 , Al, Fe, Cu, Ni), parasitological (helminthes eggs) and bacteriological (total coliforms, fecal coliforms, fecal streptococcus). The results show that, the physico-chemical quality of well waters generally approaches the WHO standards of crop watering water. The physico-chemical of streams waters and bacteriological quality of wells and streams waters are bad, according to WHO guide. These bad quality waters could contaminate crops, some of which are eaten raw, which is surely a cause of the outbreak of waterborne diseases in the city. The waters from streams are more affected. The pretreatment of the water before use for irrigation of vegetables is highly recommended. 展开更多
关键词 watering WATER Quality Urban Market GARDENING Sanitary Risks
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Seed Germination and Effects of Three Watering Regimes on the Growth of <i>Dialium guineense</i>(Wild) Seedlings
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作者 O. Olajide A. A. Oyedeji +1 位作者 G. S. Tom J. Kayode 《American Journal of Plant Sciences》 2014年第20期3049-3059,共11页
The effectiveness of three pre-germination treatments in breaking dormancy of the seeds of Dialum guineense and effects of three watering regimes on the growth performance of the seedlings were investigated. The pre-g... The effectiveness of three pre-germination treatments in breaking dormancy of the seeds of Dialum guineense and effects of three watering regimes on the growth performance of the seedlings were investigated. The pre-germination treatments were: soaking in hot water for 10 seconds and cooling down in cold water (T1), soaking in cold water for 24 hours (T2), soaking in running water for 48 hours (T3) and control (T4), while watering regimes include: watering once daily in the morning (W1), watering once every two days in the morning (W2) and watering once every three days in the morning (W3). The results showed that germination occurred first at 5 days after sowing (5 DAS) among the seeds soaked in cold water for 24 hours before sowing (T2), while the untreated seeds (control) took the longest period of 12 days before germination occurred. T1 had the highest germination value of 49.6% while T3 had the least of 31.2%. The effects of watering regimes were found to be significantly different on stem-collar diameter, leaf area and total dry weight (P < 0.05). The least significant difference (LSD) test showed that W2 and W3 supported the best growth performance. It is concluded from the results that T2 should be adopted for breaking the dormancy of Dialium guineense seeds and watering interval of three days would not dispose the seedlings to water-stress. 展开更多
关键词 Dialium guineense Seeds DORMANCY Pre-Germination SEEDLINGS GROWTH watering Regimes
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Understanding Differential Responses of Grapevine (Vitis vinifera L.) Leaf and Fruit to Water Stress and Recovery Following Re-Watering 被引量:1
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作者 Bhaskar Bondada Janani Shutthanandan 《American Journal of Plant Sciences》 2012年第9期1232-1240,共9页
Among all fruit crops of horticultural importance, grapevines (Vitis vinifera L.) stand out as the most drought tolerant crop species whose tolerance is credited to their proficiency to recover from water stress in bo... Among all fruit crops of horticultural importance, grapevines (Vitis vinifera L.) stand out as the most drought tolerant crop species whose tolerance is credited to their proficiency to recover from water stress in both the natural and vineyard growing conditions. However, information on the recovery responses is relatively scant. Studies were conducted to address this issue using potted vines of the grapevine cultivar, Cabernet Sauvignon, which was subjected to water stress and along with anatomical and ultrastructural characterizations, physiological status was assessed in healthy and water stressed vines, and following recovery via rewatering from the water stressed vines. Water stress induced wilting of leaves, drooping of tendrils, and desiccation followed by abscission of shoot tip leaving behind a brown scar at the shoot apex. The wilted leaves accumulated ABA, which correspondingly reduced stomatal conductance and leaf water potential. Upon re-watering, both these parameters made a recovery with values similar to healthy leaves. Likewise, leaf anatomical features following rewatering resembled to that of healthy leaves. In clusters, water stress caused shriveling of preveraison (unripened) berries, which regained full turgor following water resupply, whereas the postveraison (ripening) berries in the same cluster remained unaffected as evidenced by the presence of viable mesocarp cells and epicuticular wax in the form of platelets. The study revealed that shoot tip with leaf primordia was most sensitive to water stress followed by fully expanded leaves and preveraison berries, whereas the postveraison berries remained unaffected. This information could be valuable to implementing irrigation strategies towards sustaining grape production in existing vineyards experiencing episodic droughts and targeted areas prone to drought. 展开更多
关键词 ABA Berry LEAF WATER Potential WATER Stress VITIS VINIFERA
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Application of Colligative Properties in Quality Detection of Watering Raw Milk
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作者 LIN Fang-dong JIANG Zhen-ju CAO Rui 《Animal Husbandry and Feed Science》 CAS 2011年第2期42-44,共3页
[ Objective] To investigate the effects of different water amount on freezing point of raw milk. EMetbodl The freezing point of raw milk added water at different proportions was detected by SWC-LG freezing point detec... [ Objective] To investigate the effects of different water amount on freezing point of raw milk. EMetbodl The freezing point of raw milk added water at different proportions was detected by SWC-LG freezing point detector. The linear regression equation was obtained. The reproduc- ibility was checked. The water content in raw milk was calculated according to the standard regression curve. E Result~ When the water content changed from 0 to 10%, the freezing point of raw milk increased linearly. As evidenced by the reproducibility test, the standard deviation and rela- tive standard deviation were less than 1%. The milk concentration obtained by detecting the freezing point of blind milk samples had an absolute er- ror of no more than 0.5%, compared with actual watering milk concentration. [ ConcluMonl Water content in raw milk can be determined by measur- ing freezing point, and this method is reliable and reproducible. 展开更多
关键词 Raw milk Freezing point Water content
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Insights on advanced substrates for controllable fabrication of photoanodes toward efficient and stable photoelectrochemical water splitting 被引量:1
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作者 Huilin Hou Gang Shao +2 位作者 Yang Wang Wai‐Yeung Wong Weiyou Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期164-221,共58页
Conversion of solar energy into H_(2) by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PEC cell,the construction of p... Conversion of solar energy into H_(2) by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PEC cell,the construction of photoanodes is crucial to guarantee the high efficiency and stability of PEC reactions,which fundamentally rely on rationally designed semiconductors(as the active materials)and substrates(as the current collectors).In this review work,we start with a brief introduction of the roles of substrates in the PEC process.Then,we provide a systematic overview of representative strategies for the controlled fabrication of photoanodes on rationally designed substrates,including conductive glass,metal,sapphire,silicon,silicon carbide,and flexible substrates.Finally,some prospects concerning the challenges and research directions in this area are proposed. 展开更多
关键词 hydrogen PHOTOANODE PHOTOELECTROCHEMICAL SUBSTRATES water splitting
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Experimental study on the effect of water absorption level on rockburst occurrence of sandstone 被引量:1
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作者 Dongqiao Liu Jie Sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions 被引量:1
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and N reduction plant density MAIZE grain yield N uptake compensation effect
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Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design 被引量:1
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作者 Rongrong Deng Mengwei Guo +1 位作者 Chaowu Wang Qibo Zhang 《Nano Materials Science》 EI CAS CSCD 2024年第2期139-173,共35页
Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high... Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed. 展开更多
关键词 Co-P electrocatalysts Water splitting Hydrogen production Catalytic mechanism Synthesis technique Optimization design
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Investigation of hydroxyl-terminated polybutadiene propellant breaking characteristics and mechanism impacted by submerged cavitation water jet 被引量:1
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作者 Wenjun Zhou Meng Zhao +3 位作者 Bo Liu Youzhi Ma Youzhi Zhang Xuanjun Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期559-572,共14页
A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impac... A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impact are unclear.This study aims to understand those impact breaking mechanisms.The hydroxyl-terminated polybutadiene(HTPB)propellant was chosen as the research material,and a self-designed test system was used to conduct impact tests at four different working pressures.The high-speed camera characterized crack propagation,and the DIC method calculated strain change during the impact process.Besides,micro and macro fracture morphologies were characterized by scanning electron microscope(SEM)and computed tomography(CT)scanning.The results reveal that the compressive strain concentration region locates right below the nozzle,and the shear strain region distributes symmetrically with the jet axis,which increases to 4% at first 16th ms,the compressive strain rises to 2% and 6% in the axial and transverse direction,respectively.The two tensile cracks formed first at the compression strain concentrate region,and there generate many shear cracks around the tensile cracks,and those shear cracks that develop and aggregate cause the cracks to become wider and cut through the tensile cracks,forming the tensile-shear cracks and the impact parts eventually fail.The HTPB propellant forms a breaking hole shaped conical after impact 10 s.The mass loss increases by 17 times at maximum,with the working pressure increasing by three times.Meanwhile,the damage value of the breaking hole remaining on the surface increases by 7.8 times while 2.9 times in the depth of the breaking hole.The breaking efficiency is closely affected by working pressures.The failure modes of HTPB impacted by SCWJ are classified as tensile crack-dominated and tensile-shear crack-dominated damage mechanisms. 展开更多
关键词 Submerged cavitation water jet Hydroxyl-terminated polybutadiene propellant Breaking characteristics Failure modes
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Recent advances and future prospects on Ni_(3)S_(2)-Based electrocatalysts for efficient alkaline water electrolysis 被引量:1
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作者 Shiwen Wang Zhen Geng +4 位作者 Songhu Bi Yuwei Wang Zijian Gao Liming Jin Cunman Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期659-683,共25页
Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.However,efficient and economic... Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.However,efficient and economic H_(2) production by alkaline water electrolysis is hindered by the sluggish hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Therefore,it is imperative to design and fabricate high-active and low-cost non-precious metal catalysts to improve the HER and OER performance,which affects the energy efficiency of alkaline water electrolysis.Ni_(3)S_(2) with the heazlewoodite structure is a potential electrocatalyst with near-metal conductivity due to the Ni–Ni metal network.Here,the review comprehensively presents the recent progress of Ni_(3)S_(2)-based electrocatalysts for alkaline water electrocatalysis.Herein,the HER and OER mechanisms,performance evaluation criteria,preparation methods,and strategies for performance improvement of Ni_(3)S_(2)-based electrocatalysts are discussed.The challenges and perspectives are also analyzed. 展开更多
关键词 Alkaline water electrolysis HYDROGEN ELECTROCATALYSTS Ni_(3)S_(2)
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Electrokinetic-mechanism of water and furfural oxidation on pulsed laser-interlaced Cu_(2)O and CoO on nickel foam 被引量:1
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 M.L.Aruna Kumari Ahreum Min Cheol Joo Moon Myong Yong Choi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期145-154,共10页
The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and... The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and Cu_(2)O/Ni O/NF electrodes via in situ pulsed laser irradiation in liquids(PLIL)for the bifunctional electrocatalysis of oxygen evolution reaction(OER)and furfural oxidation reaction(FOR),respectively.Simultaneous oxidation of NF surface to NiO and deposition of CoO and/or Cu_(2)O on NF during PLIL offer distinct advantages for enhancing both the OER and FOR.CoO/NiO/NF electrocatalyst provides a consistently low overpotential of~359 m V(OER)at 10 m A/cm^(2),achieving the maximum FA yield(~16.37 m M)with 61.5%selectivity,79.5%carbon balance,and a remarkable Faradaic efficiency of~90.1%during 2 h of FOR at 1.43 V(vs.reversible hydrogen electrode).Mechanistic pathway via in situ electrochemical-Raman spectroscopy on CoO/NiO/NF reveals the involvement of phase transition intermediates(NiOOH and CoOOH)as surface-active centers during electrochemical oxidation.The carbonyl carbon in FF is attacked by hydroxyl groups to form unstable hydrates that subsequently undergo further oxidation to yield FA products.This method holds promise for large-scale applications,enabling simultaneous production of renewable building materials and fuel. 展开更多
关键词 Pulsed laser irradiation in liquids Water and furfural oxidation In situ Raman spectroscopy CoO/NiO/nickel foam Cu_(2)O/Nio/nickel foam 2-furoic acid
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Magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) of activated sludge: Role and behavior of moisture and organics 被引量:3
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作者 Xinxin Guo Xu Qian +1 位作者 Yili Wang Huaili Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第12期147-158,共12页
In this study, a magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) process with magnetic micro-particle conditioning–drainage under gravity–mechanical compression–electr... In this study, a magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) process with magnetic micro-particle conditioning–drainage under gravity–mechanical compression–electrical compression(MMPC–DG–MC–EC) stages was established to study the distribution and migration of water, extracellular polymeric substances(EPS), and other organic matter in the activated sludge(AS) matrix at each stage.Results showed that the MPEOD process could attain 53.52% water content(WC) in dewatered AS with bound water(BW) and free water(FW) reduction rates of 82.97% and 99.67%,respectively. The coagulation and time-delayed magnetic field effects of magnetic microparticles(MMPs) along the MMPC–DG–MC stages initiated the transformation of partial BW to FW in AS. EC had a coupling driving effect of electro-osmosis and pressure on BW, and the changes in pH and temperature at EC stage induced the aggregation of AS flocs and the release of partial BW. Additionally, MMPs dosing further improved the dewatering performance of AS by acting as skeleton builders to provide water passages. Meanwhile, MMPs could disintegrate sludge cells and EPS fractions, thereby reducing tryptophan-like protein and byproduct-like material concentrations in LB-EPS as well as protein/polysaccharide ratio in AS matrix, which could improve AS filterability. At EC stage, the former four Ex/Em regions of fluorescence regional integration analysis for EPS were obviously reduced, especially the protein-like substances in LB-and TB-EPS, which contributed to improvement of AS dewaterability. 展开更多
关键词 Activated sludge Magnetic micro-particle Pressurized vertical electro-osmotic dewatering Water distribution Extracellular polymeric substance Fluorescence regional integration analysis
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Effect of vacuum degree and aeration rate on sludge dewatering behavior with the aeration-vacuum method 被引量:3
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作者 Yu-feng GAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第9期638-655,共18页
Due to large-scale dredging operations, a large amount of sludge is inevitably produced. Large areas of land are occupied when the dredged sludge is discarded in the disposal site as waste material. The sludge dewater... Due to large-scale dredging operations, a large amount of sludge is inevitably produced. Large areas of land are occupied when the dredged sludge is discarded in the disposal site as waste material. The sludge dewatering with aeration-vacuum (SDAV) method is suit for treating the sludge with high water content and high clay content in the disposal site. The water in the sludge can be discharged out. The volume of the sludge can be reduced quickly, and the recycling of the land can be accelerated by this method. Most importantly, this technique is an efficient way to deal with clogging problems when pumping water from high water content, high clay content dredged sludge. Vacuum degree range tests, the aeration rate range tests, and the influencing factors of sludge dewatering behavior tests were conducted with a self-developed SDAV model test device. Sludge samples were taken from the South-to-North Water Diversion East Line Project in Huai’an White-Horse Lake disposal site, Jiangsu Province, China. The optimal range of vacuum degree and aeration rate were obtained through the test results, and the mechanisms for how the two factors work and how they affect the sludge dewatering behavior were analyzed. The suitable vacuum degree range in SDAV is below 50 kPa, and the suitable aeration rate is about 1.0 m3/h. The low-vacuum degree contributes to reduce the ad-sorption effect of micro-channels on soil particles in filter material and to maintain the arch structures. Aeration has the effects of expansion, disturbance, changing Reynolds number, and dynamic sieve separating. The pump quantity of water per meter of filter tube (m) has different change rules as the vacuum degree changes under different aeration rates. The reason is that the formed arch structures’ conformation and permeability differ greatly under different combined-conditions of vacuum degree and aeration rate. The optimal combined-condition for dewatering the sludge is 35 kPa with 1.0 m3/h. 展开更多
关键词 High water content dredged sludge Sludge dewatering with aeration-vacuum (SDAV) Vacuum degree Aeration rate Arch structures
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Temporal and spatial variation and prediction of water yield and water conservation in the Bosten Lake Basin based on the PLUS-InVEST model
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作者 CHEN Jiazhen KASIMU Alimujiang +3 位作者 REHEMAN Rukeya WEI Bohao HAN Fuqiang ZHANG Yan 《Journal of Arid Land》 SCIE CSCD 2024年第6期852-874,共23页
To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research ... To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research was based on land use/land cover(LULC),natural,socioeconomic,and accessibility data,utilizing the Patch-level Land Use Simulation(PLUS)and Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)models to dynamically assess LULC change and associated variations in water yield and water conservation.The analyses included the evaluation of contribution indices of various land use types and the investigation of driving factors that influence water yield and water conservation.The results showed that the change of LULC in the Bosten Lake Basin from 2000 to 2020 showed a trend of increasing in cultivated land and construction land,and decreasing in grassland,forest,and unused land.The unused land of all the three predicted scenarios of 2030(S1,a natural development scenario;S2,an ecological protection scenario;and S3,a cultivated land protection scenario)showed a decreasing trend.The scenarios S1 and S3 showed a trend of decreasing in grassland and increasing in cultivated land;while the scenario S2 showed a trend of decreasing in cultivated land and increasing in grassland.The water yield of the Bosten Lake Basin exhibited an initial decline followed by a slight increase from 2000 to 2020.The areas with higher water yield values were primarily located in the northern section of the basin,which is characterized by higher altitude.Water conservation demonstrated a pattern of initial decrease followed by stabilization,with the northeastern region demonstrating higher water conservation values.In the projected LULC scenarios of 2030,the estimated water yield under scenarios S1 and S3 was marginally greater than that under scenario S2;while the level of water conservation across all three scenarios remained rather consistent.The results showed that Hejing County is an important water conservation function zone,and the eastern part of the Xiaoyouledusi Basin is particularly important and should be protected.The findings of this study offer a scientific foundation for advancing sustainable development in arid watersheds and facilitating efficient water resource management. 展开更多
关键词 PLUS model InVEST model Bosten Lake Basin water yield water conservation land-use simulation Geodetector
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Vibronic effect study of ^(1)A_(2) state of H_(2)O and D_(2)O
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作者 张倍源 王礼涵 +5 位作者 朱剑辉 徐卫青 马子茹 赵小利 吴勇 朱林繁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期395-399,共5页
The generalized oscillator strengths of the dipole-forbidden excitations of the ^(1)A_(2) of H_(2)O and D_(2)O were calculated with the time dependent density functional theory,by taking into account the vibronic effe... The generalized oscillator strengths of the dipole-forbidden excitations of the ^(1)A_(2) of H_(2)O and D_(2)O were calculated with the time dependent density functional theory,by taking into account the vibronic effect.It is found that the vibronic effect converts the dipole-forbidden excitation of the ^(1)A_(2) into a dipole-allowed one,which enhances the intensities of the corresponding generalized oscillator strength in the small squared momentum transfer region.The present investigation shows that the vibronic effect of H_(2)O is slightly stronger than that of D_(2)O,which exhibits a clear isotopic effect. 展开更多
关键词 WATER heavy water generalized oscillator strength vibronic effect isotope effect
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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses
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作者 Ting Wang Qing Xu +4 位作者 Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun Zuo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期42-53,共12页
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and... Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates. 展开更多
关键词 Stable carbon isotope Water use efficiency THINNING Understory removal Photosynthetic capacity Needle water potential
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Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin
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作者 CHEN Biying FANG Lujia +4 位作者 LANG Yunchao XU Sheng LIU Congqiang ZHANG Luyuan HOU Xiaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期207-219,共13页
The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological setting.To better identify the origin and evolution of coal seam water and its impact on gas ... The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological setting.To better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I concentrations.The calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal deposition.The model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in Cenozoic.The spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin center.This study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production. 展开更多
关键词 CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin
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