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Transcriptional regulation of MdPIN7 by MdARF19 during gravityinduced formation of adventitious root GSA in self-rooted apple stock
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作者 Zenghui Wang Xuemei Yang +5 位作者 Linyue Hu Wei Liu Lijuan Feng Xiang Shen Yanlei Yin Jialin Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1073-1084,共12页
Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the... Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling rootstock.Therefore,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock cultivars.An apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.MdARF19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple stock.However,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of MdFLP.Our findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals. 展开更多
关键词 APPLE Self-rooted stock gravity MdARF19 MdPIN7 Gravitropic set-point angle Transcriptional regulation
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NMR studies of stock process water and reaction pathways in hydrothermal carbonization of furfural residue 被引量:1
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作者 Fen Yue Christian Marcus Pedersen +5 位作者 Xiuyin Yan Yequn Liu Danlei Xiang Caifang Ning Yingxiong Wang Yan Qiao 《Green Energy & Environment》 SCIE 2018年第2期163-171,共9页
Hydrothermal carbonization(HTC) is a valuable approach to convert furfural residue(FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains... Hydrothermal carbonization(HTC) is a valuable approach to convert furfural residue(FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques(~1H and ^(13)C NMR,~1H-~1H COSY and ~1H-^(13)C HSQC etc.) especially 1D selective gradient total correlation spectroscopy(TOCSY NMR) were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions(180-240 ℃ at 8 h, and 1-24 h at 240 ℃) was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies. 展开更多
关键词 NMR Hydrothermal carbonization Furfural residue stock process water
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Theoretical exploration of water injection gravity flooding oil in ultra-deep fault-controlled fractured-cavity carbonate reservoirs 被引量:2
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作者 YANG Xuewen WANG Rujun +3 位作者 DENG Xingliang LI Shiyin ZHANG Hui YAO Chao 《Petroleum Exploration and Development》 CSCD 2022年第1期133-143,共11页
Based on the analysis of geological characteristics of ultra-deep fault-controlled fracture-cavity carbonate reservoirs and division of reservoir units, two physical models were made, and physical simulations of oil d... Based on the analysis of geological characteristics of ultra-deep fault-controlled fracture-cavity carbonate reservoirs and division of reservoir units, two physical models were made, and physical simulations of oil displacement by water injection were carried out to find out water flooding mechanism in the fault-controlled fracture-cavity carbonate reservoir under complex flow state. On this basis, a mathematical model of fault-controlled carbonate reservoir with coexisting seepage and free flow has been established. Pilot water injection tests have been carried out to evaluate the effects of enhancing oil recovery by water injection. The results show that: fault-controlled fracture-cavity carbonate reservoir units can be divided into three types:the strong natural energy connected type, the weak natural energy connected type and the weak natural energy isolated type;the fault-fracture activity index of the fault-controlled fractured-cavity body can effectively characterize the connectivity of the reservoir and predict the effective direction of water injection;the mathematical model of fault-controlled carbonate reservoir with coexisting seepage and free flows can quantitatively describe the fluid flow law in the fracture-cavity body;the water injected into the fault-controlled fracture-cavity body is weakly affected by the capillary force of the lithologic body, and the oil-water movement is mainly dominated by gravity. The development modes of single well water injection, unit water injection,and single well high pressure water injection proposed based on the connection structure of fracture-cavity space and well storage space configuration are confirmed effective by pilot tests, with obvious water injection gravity flooding effect. 展开更多
关键词 Tarim Basin ORDOVICIAN fault-controlled carbonate reservoir fractured-cavity carbonate reservoir water flooding gravity flooding EOR
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The patterns of surface capillary-gravity short-crested waves with uniform current fields in coastal waters 被引量:3
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作者 Hu Huang Jia Fu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第5期433-441,共9页
A fully three-dimensional surface gravitycapillary short-crested wave system is studied as two progressive wave-trains of equal amplitude and frequency, which are collinear with uniform currents and doubly-periodic in... A fully three-dimensional surface gravitycapillary short-crested wave system is studied as two progressive wave-trains of equal amplitude and frequency, which are collinear with uniform currents and doubly-periodic in the horizontal plane, are propagating at an angle to each other. The first- and second-order asymptotic analytical solutions of the short-crested wave system are obtained via a perturbation expansion in a small parameter associated with the wave steepness, therefore depicting a series of typical three-dimensional wave patterns involving currents, shallow and deep water, and surface capillary waves, and comparing them with each other. 展开更多
关键词 Short-crested waves Uniform currents PATTERNS Surface capillary-gravity waves Finite depth and deep water
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Wind-Driven Slanting Profile Wave Derived from the Unified Variational Principle of Water Gravity Wave
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作者 Fu Yuhua(China Offshore Oil Production Research Center) 《Marine Science Bulletin》 CAS 1999年第2期36-44,共9页
Considering that at present the regular waves in common use have the profile symmetrized to a vertical axis, which are different from actual wind-driven sea waves, and based on deriving linear wave, solitary wave, fif... Considering that at present the regular waves in common use have the profile symmetrized to a vertical axis, which are different from actual wind-driven sea waves, and based on deriving linear wave, solitary wave, fifth order Stokes wave and stream function wave by using Unified Variational Principle of Water Gravity Wave (UVPWGW), this paper derives wind-driven slanting profile wave by using UVPWGW. Its feature is that under the action of wind pressure, the wave profile is not symmetrized to a vertical axis, but that it is in the forward slanting form. 展开更多
关键词 UNIFIED VARIATIONAL principle of water gravity WAVE WIND-DRIVEN WAVE slanting PRofILE
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An estimation of groundwater storage variations from GRACE gravity satellites in the Heihe River Basin, northwestern China
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作者 YanPing Cao ZhuoTong Nan XingLin Hu 《Research in Cold and Arid Regions》 CSCD 2014年第6期577-586,共10页
There are only limited surface water resources available in the Heihe River Basin (HRB), a typical inland river basin in the arid region of northwestern China, where groundwater overexploitation is a serious problem... There are only limited surface water resources available in the Heihe River Basin (HRB), a typical inland river basin in the arid region of northwestern China, where groundwater overexploitation is a serious problem. Groundwater has become one of main resources of fresh water in the HRB. In this paper, temporal and spatial variations of groundwater in the HRB are estimated by the Gravity Recovery and Climate Experiment (GRACE) satellites. Our analysis shows that groundwater storage in the HRB reaches its highest in the summer of 2005, and then begins to decline in the following years and reaches steady status in 2008. Spatially, groundwater shows a decline in the upper HRB in the first two years and a slight increase in the following years, while this phenomenon is reversed in the middle HRB where groundwater slightly increases in 2005 and then declines in the following three years. In the lower HRB, GRACE detects a continual increase in the full six-year period. This approach is proven successful when employed in the HRB and thus offers a new insight into monitoring groundwater variations in a river basin with limited or even without any observed data. 展开更多
关键词 GRACE gravity satellites GROUNDwater Heihe River Basin terrestrial water storage
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Suitable Date of Seeding, Planting Density and Water Use Efficiency for Propagation of Stock Seed Potato in Mountainous Region of Southwest Sichuan 被引量:2
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作者 沈学善 罗李飞 +1 位作者 李春荣 黄钢 《Agricultural Science & Technology》 CAS 2012年第9期1904-1907,共4页
[Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "C... [Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "Chuanyu 13" was used as material to study the effects of date of seeding and density on growing period, germination rate, yield and water use efficiency of spring potato in the field. [Result] With the postponement of date of seeding, the days from sowing to germination shortened, while the germination rate, the number of tubers per plant, the number of middle and small tubers in a group, yield and water use efficiency all increased. Planting density had no effects on the days from sowing to germination and the ger- mination rate, while the number of tubers per ptant, the number of middle and small tubers in a group, yield and water use efficiency increased significantly along with the increasing planting density. [Conclusion] At an elevation of 1 200 m to 1 250 m in Ebian County, the suitable date of seeding for potato was from February 9 to March 1, and the suitable planting density was 12×10^4 plants per hm^2, however, in the optimum planting density has not been found so that it needs further research, 展开更多
关键词 Date ofseedingi Planting density stock seed YIELD water use efficiency
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Temporal and spatial distributions of dominant shrimp stocks and their relationship with the hydrological environment in the East China Sea 被引量:11
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作者 吕华庆 宋海棠 Chris BAYLY 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第4期386-397,共12页
To provide a scientific and technological base for fishery administration, holding a moratorium on fishing, and combating habitat degradation, a shrimp stock survey was carried out in May, August, and November 1998 an... To provide a scientific and technological base for fishery administration, holding a moratorium on fishing, and combating habitat degradation, a shrimp stock survey was carried out in May, August, and November 1998 and in February 1999. The study was conducted in the area between 26°00' N and 33°00' N and to the west of 127°00' E in the East China Sea using a multi-sac trawl-net, with 115 stations being sampled. Up to 2001, we had found 121 species, which belong to 63 genera under 22 families, and 41 species are of high economic value and in great abundance. Nine shrimp species were of great economic importance, whose stock accounted for 76.8% of the demersal total. They were Parapenaeus fissuroides, Metapenaeopsis philippi, Palaemon gravieri, Metapenaeopsis barbata, Solenocera koelbeli, Solenocera crassicornis, Trachypenaeus curvirostris, Solenocera melantho and Parapenaeopsis hardwickii (listed in stock order). The nine species belong to the eurythermal and eurysaline community and high thermal and high saline community, had different migration patterns and stocks, and their distribution patterns could be generally classified into three types: (1) dominating in the north or the south; (2) dominating to the north of and in the coast to the south of 30000' N; and (3) dominating to the east of 60 m isobath, which were related to six water masses in the ECS near two lines, i.e., the 60 m isobath and 30°00'N latitudinal lines. Densely habited shrimps were found in all four seasons due to temperature and salinity frontiers and upwelling. The general stock density index was relatively higher in spring, summer, and autumn, when it surpassed 10 kg/h, while in winter, it was only 6.8 kg/h which might be caused by overfishing. According to the spawning areas of the nine species and their distribution patterns, to attain sustainable development of the shrimp fishery in the ECS, it is imperative to protect fishing areas and to hold a moratorium on catching to the west of 60 m isobath from April through October, and between 60 m and 100 m isobaths and to the south of 30°N from June through August and to limit fishing in winter. 展开更多
关键词 shrimp stock survey CONSERVATION moratorium COMMUNITY water system
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GRACE-based estimates of water discharge over the Yellow River basin 被引量:4
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作者 Qiong Li Bo Zhong +1 位作者 Zhicai Luo Chaolong Yao 《Geodesy and Geodynamics》 2016年第3期187-193,共7页
As critical component of hydrologic cycle, basin discharge is a key issue for understanding the hydrological and climatologic related to water and energy cycles. Combining GRACE gravity field models with ET from GLDAS... As critical component of hydrologic cycle, basin discharge is a key issue for understanding the hydrological and climatologic related to water and energy cycles. Combining GRACE gravity field models with ET from GLDAS models and precipitation from GPCP, discharge of the Yellow River basin are estimated from the water balance equation. While comparing the results with discharge from GLDAS model and in situ measurements, the results reveal that discharge from Mosaic and CLM GLDAS model can partially represent the river discharge and the discharge estimation from water balance equation could reflect the discharge from precipitation over the Yellow River basin. 展开更多
关键词 GRACE gravity field model Terrestrial water storage water discharge Yellow River basin
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Forest aboveground biomass estimates in a tropical rainforest in Madagascar: new insights from the use of wood specific gravity data 被引量:2
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作者 Tahiana Ramananantoandro Herimanitra P.Rafidimanantsoa Miora F.Ramanakoto 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期47-55,共9页
To generate carbon credits under the Reducing Emissions from Deforestation and forest Degradation program(REDD+), accurate estimates of forest carbon stocks are needed. Carbon accounting efforts have focused on car... To generate carbon credits under the Reducing Emissions from Deforestation and forest Degradation program(REDD+), accurate estimates of forest carbon stocks are needed. Carbon accounting efforts have focused on carbon stocks in aboveground biomass(AGB).Although wood specific gravity(WSG) is known to be an important variable in AGB estimates, there is currently a lack of data on WSG for Malagasy tree species. This study aimed to determine whether estimates of carbon stocks calculated from literature-based WSG values differed from those based on WSG values measured on wood core samples. Carbon stocks in forest biomass were assessed using two WSG data sets:(i) values measured from 303 wood core samples extracted in the study area,(ii) values derived from international databases. Results suggested that there is difference between the field and literaturebased WSG at the 0.05 level. The latter data set was on average 16 % higher than the former. However, carbon stocks calculated from the two data sets did not differ significantly at the 0.05 level. Such findings could be attributed to the form of the allometric equation used which gives more weight to tree diameter and tree height than to WSG. The choice of dataset should depend on the level of accuracy(Tier II or III) desired by REDD+. As higher levels of accuracy are rewarded by higher prices, speciesspecific WSG data would be highly desirable. 展开更多
关键词 Biomass estimates Carbon stocks Data quality Madagascar REDD+ Wood specific gravity
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Investigation on the relation between the gravity anomaly,crustal deformation and underground water
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作者 吴雪芳 田世华 吴国华 《Earthquake Science》 CSCD 1994年第S1期41-49,共9页
Trough the practice of earthquake prediction we have found that sometimes an earthquake doesn' t occur in the gravity anomaly region or the magnitude of earthquake that has occurred does not corrrespond to the val... Trough the practice of earthquake prediction we have found that sometimes an earthquake doesn' t occur in the gravity anomaly region or the magnitude of earthquake that has occurred does not corrrespond to the value of gravity anomaly. The main reason of this is related to crust deformation or behavior of undergroud water.In this paper, based on the theory of elasticity and dynamics, the gravity effect associated with the elevation variation, density change and mass migration under the observation point as well as the relationshipe between gravity of feet and crustal activity are studied. The relationship between the variation of gravity and crust vertical deformation, underground water, precipitation are researched; besides the order of magnitude, time and pattern of the influence are studied in order to obtain the gravitational precursors directly related to earthquakes.Theory and practice have proved that crust deformation caused by pumping underground water or extracting petroleum and gravity changes are linearly related. This paper shows that the effect and influence produced by different aquifers to the gravity changes are also different. Phreatic water is the main factor which causes the gravity changes. The second factor is precipitation which influences the humidity of soil, as a result the gravity changes. The confined water, when there is no pumping, whatsoever the rise or fall of its level almost has no influence on the gravity changes.Observation data of Northern China and areas of South-western China verified the consistency of practice with theory. 展开更多
关键词 gravity change crustal deformation confined water phreatic water
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Temporal and Spatial Seasonal Variations in Quality of Gravity Flow Water in Kyanamira Sub-County, Kabale District, Uganda
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作者 Hannington Ngabirano Denis Byamugisha Emmanuel Ntambi 《Journal of Water Resource and Protection》 2017年第5期455-469,共15页
The study was designed to investigate temporal and spatial seasonal variations in quality properties of gravity flow water samples collected from Kigata, Kacuro, Kihanga, Kitibya and Kanjobe located in Kyanamira Sub-C... The study was designed to investigate temporal and spatial seasonal variations in quality properties of gravity flow water samples collected from Kigata, Kacuro, Kihanga, Kitibya and Kanjobe located in Kyanamira Sub-County, Kabale District, Uganda. Physical, chemical and biological parameters such as pH, temperature, dissolved oxygen, total dissolved solids, electrical conductivity, turbidity, colour and total suspended solids, total hardness, total alkalinity, chloride, fluoride, nitrates-N, nitrites-N, ammonium-N, sulphates, total phosphate, sodium, calcium, magnesium and some heavy metals were analyzed. Total iron, lead, chromium, copper, zinc, manganese and cadmium were analyzed by atomic absorption spectrometry. Two of the basic biological parameters for drinking water such as faecal coliforms and salmonella were analyzed by incubation followed by counting colony forming units (CFUs). Statistical presentations of data including cluster analysis, dendrograms and principal component analysis were used with the assistance of PAST software. Temperature, pH, TDS dissolved oxygen, cations, anions (chemical parameters) and salmonella, faecal coliforms were the major contributing parameters to gravity flow water’s quality variations during both seasons. Values of pH ranged between 3.78 and 4.84 from March to August in all study sites and they were consistently below the WHO permissible pH range of 6.5 - 8.5. Total suspended solids ranged between 0.66 and 2.17 mg·L-1 and were above the recommended WHO limit of zero value in all study sites. Salmonella and faecal coliforms colonies were present in scaring numbers in the wet season. In March, salmonella counts at Kacuro (14 CFU) and Kanjobe (128 CFU) while faecal coliforms counts at Kacuro (515 CFU) and Kanjobe (228 CFU). The findings of this study call for special attention when using gravity flow water. 展开更多
关键词 TEMPORAL SPATIAL SEASONAL Variations gravity Flow water Physical Chemical and Biological Parameters
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Gravity change and its mechanism after the first water impoundment in Three Gorges Project
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作者 孙少安 项爱民 +1 位作者 朱平 申重阳 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第5期522-529,共8页
In this paper we have analyzed precise gravity survey and gravity effects resulted from water loading, crustal deformation, ground water level change and precipitation before and after the water impoundment in the Thr... In this paper we have analyzed precise gravity survey and gravity effects resulted from water loading, crustal deformation, ground water level change and precipitation before and after the water impoundment in the Three Gorges Reservoir. We found that: ① In dam area of the reservoir, gravity effect resulted from water load increase is the most significant, maximum gravity change is 200×10^-8 m/s^2, but this effect is limited in amplitude and range. Gravity change can be observed about 5 km offshore. The gravity change caused by ground water level change is regional; and the impact of precipitation on it should not be neglected. ② At head area of the reservoir, the maximum gravity change is near Xiangxi. Monitoring the variation of gravity field and further study should continue in the future. 展开更多
关键词 the Three Gorges Project the first water impoundment gravity change
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Spatial and temporal variation of gravity field in the capital region
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作者 华昌才 果勇 +1 位作者 刘瑞法 肖钢 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第3期427-433,共7页
The high accurate gravity measurement have been carried out many years in the capital region. The main characteristics of the change of gravity field during the latest eight years (1981 - 1988) in the region are prese... The high accurate gravity measurement have been carried out many years in the capital region. The main characteristics of the change of gravity field during the latest eight years (1981 - 1988) in the region are presented inthis paper. The more gravitational variation appeared in the southern and south-eastern part, the maximum variation come to 10-6 ms-2. In the northern part, for instance: Chengde City, and Wan-clan County - westTaihang mountain area which are in the westside of the network, were relative stable. The noticeable areas ofgravitational variation were in Tianjin-Baxian-Renqiu which correspon d with the crustal vertical deformation.The main cause of that is related to pump ground water and petroleum. 展开更多
关键词 vertical deformation ground water gravity variation
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Proof of Six-Wave Resonance Conditions of Ocean Surface Gravity Waves in Deep Water
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作者 LIN Guo-bin HUANG Hu 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期734-738,共5页
A necessary big step up in the modern water wave theories and their widespread application in ocean engineering is how to obtain 6-wave resonance conditions and to prove it. In the light of the existing forms and char... A necessary big step up in the modern water wave theories and their widespread application in ocean engineering is how to obtain 6-wave resonance conditions and to prove it. In the light of the existing forms and characteristics of 3-wave, 4-wave and 5-wave resonance conditions, the 6-wave resonance conditions are proposed and proved for currently a maximum wave-wave resonance interactions of the ocean surface gravity waves in deep water, which will be indispensable to both the Kolmogorov spectrum of the corresponding universal wave turbulence and a synthetic 4-5-6-wave resonant model for the ocean surface gravity waves. 展开更多
关键词 6-wave resonance conditions PROof ocean surface gravity waves in deep water wave turbulence
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The Impact of Orographically-Induced Gravity Waves on the Diurnal Cycle of Rainfall over Southeast Kalimantan Island
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作者 Jun-Ichi HAMADA Manabu D.YAMANAKA +1 位作者 Jun MATSUMOTO Masayuki HARA 《Atmospheric and Oceanic Science Letters》 2009年第1期35-39,共5页
Precipitation measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite indicate that the southeastern area of Kalimantan (Borneo) Island receives much less rainfall than elsewhere on the island durin... Precipitation measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite indicate that the southeastern area of Kalimantan (Borneo) Island receives much less rainfall than elsewhere on the island during the period from July to October.Results from sur-face meteorological observations show that the diurnal cycle of rainfall differs greatly between the eastern and western coasts of the island.Rainfall on the western coast of the island is frequent in the afternoon and evening,whereas almost all rainfall on the eastern coast occurs in the morning.Meanwhile,the Global Positioning System (GPS)-derived precipitable water (PW) on the eastern coast shows a substantial decrease in moisture in the af-ternoon and evening.Numerical experiments with a mesoscale model reveal that gravity waves driven by di-urnal heating of the elevated land surface of the moun-tains on Sulawesi Island,which lies approximately 300 kilometers to the east of Kalimantan Island,significantly affect the diurnal cycle of rainfall over southeast Kali-mantan Island. 展开更多
关键词 diurnal cycle RAINFALL precipitable water Kalimantan (Borneo) Island gravity wave
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Stream Function Wave Derived by Unified Variational Principle of Water Gravity Wave
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作者 Fu Yuhua Senior Engineer, China Offshore Oil Production Research Center, P.O.Box 9607, Beijing, 100086 《China Ocean Engineering》 SCIE EI 1997年第2期187-200,共14页
Based on the linear wave, solitary wave and fifth order stokes wave derived by use of the Unified Variational Principle of Water Gravity Wave (UVPWGW), this paper derives stream function wave theory by using UVPWGW. T... Based on the linear wave, solitary wave and fifth order stokes wave derived by use of the Unified Variational Principle of Water Gravity Wave (UVPWGW), this paper derives stream function wave theory by using UVPWGW. This paper will handle the Kinematic Free Surface Boundary Condition (KFSBC) and Dynamic Free Surface Boundary Condition (DFSBC) directly and give the optimum solution, instead of the conditions Sigma(Q(av) - Q(i))(2) = min, and the related equations of stational condition. When the wave height H, period T and water depth D are given, the original stream function wave will be determined, and can not be adjusted if it does not agree with the real case; in the present method, the adjustment can be done by adding several constraint conditions, for example, the wave profile can be adjusted according to the condition of accurate peak position. The examples given in this paper show that for the original stream function wave, the DFSBC can be fairly well satisfied, but the KFSBC can not; however, the stream function wave derived by UVPWGW is better than the original one in the sense of minimum error squares in the aspect of the level at which KFSBC and DFSBC are satisfied. 展开更多
关键词 unified variational principle of water gravity wave stream function wave theory optimum solution
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Spatio-temporal variability of terrestrial water storage in the Yangtze River Basin: Response to climate changes
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作者 Yaoguo Wang Zhaoyang Sun +2 位作者 Qiwen Wu Jun Fang Wei Jia 《Geodesy and Geodynamics》 EI CSCD 2023年第3期201-211,共11页
The Yangtze River Basin(YRB)is an important region for China's economic development.However,it has a complex terrain layout,most of which is affected by monsoon weather,and the geographical and temporal distributi... The Yangtze River Basin(YRB)is an important region for China's economic development.However,it has a complex terrain layout,most of which is affected by monsoon weather,and the geographical and temporal distribution of water resources is severely unbalanced.Therefore,the detailed analysis of spatio-temporal water mass changes is helpful to the development and rational utilization of water resources in the YRB.In this study,the variation of terrestrial water storage(TWS)is monitored by Gravity Recovery and Climate Experiment(GRACE)satellite gravity.We find that the University of Texas Center for Space Research(CSR)solution shows a notable difference with the Jet Propulsion Laboratory(JPL)in space,but the general trend is consistent in time series.Then the GRACE inferred water mass variation reveals that the YRB has experienced several drought and flood events over the past two decades.Global Land Data Assimilation System(GLDAS)results are similar to GRACE.Furthermore,the overall precipitation trend tends to be stable in space,but it is greatly influenced by the strong El Nino-~Southern Oscillation(ENSO),which is the response to global climate change.The upper YRB is less affected by ENSO and shows a more stable water storage signal with respect to the lower YRB. 展开更多
关键词 Yangtze river basin Terrestrial water storage GRACE Time-varying gravity field
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Assessing Spatio-temporal Characteristics of Water Storage Changes in the Mountainous Areas of Central Asia Based on GRACE
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作者 ZHANG Pengfei CHEN Xi +2 位作者 BAO Anming LIU Tie Felix NDAYISABA 《Chinese Geographical Science》 SCIE CSCD 2017年第6期918-933,共16页
The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest... The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest importance for understanding regional water shortages and the main factors. Data from the GRACE (Gravity Recovery and Climate Experiment) satellites, precipitation prod- ucts and snow-covered area data were used to analyze the spatio-temporal characteristics of water storage changes and the effects of precipitation and snow cover from April 2002 to December 2013. The results were computed for each mountain ranges, and the follow- ing conclusions were drawn. The water storage in the mountainous areas of Central Asia as a whole increases in summer and winter, whereas it decreases in autumn. The water storage is affected by precipitation to some extent and some areas exhibit hysteresis. The area of positive water storage changes moves from west to east over the course of the year. The water storage declined during the period 2002-2004. It then returned to a higher level in 2005-2006 and featured lower levels in 2007-009 Subsequently, the water storage increased gradually from 2010 to 2013. The Eastern Tianshan Mountains and Western Tianshan Mountain subzones examined in this study display similar tendencies, and the trends observed in the Karakorum Mountains and the Kunlun Mountains are also similar. However, the Eastern Tianshan Mountains and Western Tianshan Mountains were influenced by precipitation to a greater degree than the latter two ranges. The water storage in Qilian Mountains showed a pronounced increasing trend, and this range is the most strongly affected by precipitation. Based on an analysis of all investigated subzones, precipitation has the greatest influence on total water storage relative to the snow covered area in some areas of Central Asia. The results obtained from this study will be of value for scientists stud- ying the mechanisms that influence changes in water storage in Central Asia. 展开更多
关键词 water storage gravity Recovery and Climate Experiment (GRACE) mountainous areas Central Asia PRECIPITATION
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Effects of Stocking Density on Water Quality,Growth and Economic Benefits of Chinese Softshelled Turtle Pelodiscus sinensis in Ponds
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作者 Wei LI Huaiyu DING +3 位作者 Fengyin ZHANG Tanglin ZHANG Jiashou LIU Zhongjie LI 《Agricultural Science & Technology》 CAS 2016年第5期1238-1242,共5页
The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return... The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return of Pelodiscus sinensis cultured in ponds.P.sinensis were stocked at densities of 1 ind./m^2(LD:low stocking density) and 2 ind./m^2(HD:high stocking density) in 3 000-m^2 ponds,with three replicate ponds for each density.P.sinensis juveniles were fed with a commercial dry pellet feed of 46% crude protein and minced fillet of silver carp ans cultured for 122 days.The results showed that the levels of total nitrogen(TN),total phosphorous(TP),Chlorophyll-a(Chl.a) and turbidity in LD treatment were significantly lower than those in HD treatment(P<0.05).The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment,respectively.Mean survival rates,final weight,average growth rates and PER were significantly higher in LD treatment compared with the HD treatment(P<0.05),respectively.Production was significantly affected by stocking density,which was higher in HD treatment,but the net income was higher in LD treatment.The results suggest that turtles with mean weight 55.6 g rearing at a low stocking density(1 ind./m^2) in ponds had a positive effect on overall economic return and was effective at improving turtle growth performance and water quality. 展开更多
关键词 Pelodiscus sinensis stocking density water quality Growth performance Economic return
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