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Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To comprehensively assess the impact of sediment retention by reservoirs on downstream fluvial processes and flood control, this study analyzed sediment and cross- sectional data collected during the sediment retention periods at the Sanmenxia ( SMX) and Xiaolangdi ( XLD) reservoirs. The research explored patterns of channel aggradation and degradation, flood scouring efficiency, channel geometric characteristics, and flood discharge capacity in the Lower Yellow River (LYR). The results revealed uneven scouring throughout the LYR, with notable riverbed coarsening—the median grain size of the bed sediment increased by 2. 1 to 2. 5 times that before scouring. Above Gaocun, enhanced flood discharge capacity at equivalent water levels was observed, and the larger channel storage can temporarily detain sediment from the XLD Reservoir. However, following riverbed coarsening, the depletion of fine and medium silt led to a significant decline in channel scouring efficiency over time. The long-term sediment and water management by the reservoirs, coupled with advanced river engineering in the LYR, shifted the focal area of channel scouring downstream during the XLD Reservoir′s sediment retention period compared to that during the SMX period. This shift was accompanied by an increase in riverbed coarsening and a marked decrease in scouring efficiency. These findings provide a scientific foundation for defining technical parameters for reservoir sediment and water regulation. [ABSTRACT FROM AUTHOR]

Feeding difficulty and easy clogging have confined the picking efficiency of green Sichuan pepper, leading to the “pile picking”. In this study, a rotating shear picking device was designed for green Sichuan pepper. Firstly, a picking scheme was determined, according to the physical and mechanical properties of prickly ash branches. The specific procedures included the rotating drive, guide feeding, and shearing picking of prickly ash branches. The reciprocating cutters were selected to realize the shear picking. The double-action reciprocating cutters were also designed for their transmission. The structure and motion parameters were determined to meet the requirements of rotary shear picking. Secondly, the simulation model was established to shear the prickly ash branch using ANSYS/LS-DYNA. The orthogonal tests were carried out with the cutting angle of the cutter tooth, the edge angle of the cutter tooth, and the thickness of the cutter tooth as the control factors, while the peak cutting force as the evaluation index. The results showed that the optimal tooth parameters were the cutting angle of 20 °, edge angle of 50°, and tooth thickness of 2.5 mm, with the peak cutting force 3.739 N, which was fully met the requirements of shear picking for the green Sichuan pepper. Finally, the prickly ash branches with fresh green Sichuan pepper were piled in the Sansheng Town, Beibei District, Chongqing, China, in June, 2023. A single-factor experiment was carried out with the branch feeding angle, branch feeding speed, and branch rotational speed as the control factors, while the picking efficiency, net collection rate, and fruit injury rate as the evaluation indices. The branch feeding angle, branch feeding speed, and branch rotation speed were determined in the range of 40°-60°, 20-40 mm/s, and 20-40 r/min, respectively. A three-factor quadratic regression orthogonal combination test was analyzed using Box-Behnken design on the Design-Expert 12. The optimal operating parameters were achieved in the branch feeding angle of 55.035°, the branch feeding speed of 32.04 mm/s, and the branch rotation speed of 29.635 r/min, in the rotating shear picking device for green Sichuan pepper. The performance was predicted as the picking efficiency of 10.78 kg/h, the net collection rate of 95.66%, and the fruit injury rate of 12.06%. The optimized parameters were rounded as the branch feeding angle of 55°, the branch feeding speed of 33.21 mm/s, and the branch rotational speed of 30r/min for the prototype test. Experiment validated that the average picking efficiency of a single person feeding a branch for the green Sichuan pepper was 10.95 kg/h using optimal operating parameters, with an average net collection rate of 95.57%, and an average fruit injury rate of 12.87%. The finding can provide the technical references to develop the picking machines for green Sichuan pepper. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since the Xiaolangdi Reservoir (XLD) operation, bed materials coarsening and changes in flow resistance have been occurring substantially in the Lower Yellow River (LYR). Thus, to quantitatively describe the effects of XLD on flow resistance in the LYR, the varying characteristics of flow velocity, river width, bed material particle diameter and Manning′s coefficient were analyzed using measured data from the hydrological stations. A movable bed resistance formula incorporating the bedform index was developed based on control factor theory and measured bedform data. The accuracy of the formula was verified using 1 508 data sets measured at the hydrological stations. The results highlight that, first, the bed material is coarser in the upper reaches and finer in the lower reaches of LYR. More developed dunes and higher flow resistance occurred in the wandering reach. Second, in reaches downstream of Gaocun, the bed coarsening and flow resistance reduction are less pronounced than in the wandering reach. The cross-section of the main channel is narrower and deeper, increasing wall resistance obviously during flood periods. XLD operation has facilitated bedforms development and increased flow resistance in the LYR. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multi-beam sounding system was used to observe the bed surface morphology of Huayuankou section in the Lower Yellow River under low sand content, and the morphological characteristics and change regularity of the bed surface were analyzed. The main channel of the Huayuankou reach was chosen for survey from June to August in 2016-2018, the bed form data of the channels with the length of 2.4-3.7 km and the width of 65-120 m under different flow conditions were collected. The results show that under the condition of low sediment concentration, the bed form of the river reach of Huayuankou of the Lower Yellow River is featured compound dunes formed by the superposition of first-order and secondary dunes. The average wavelengths of the first-order dunes are 388-955 m, the average wave heights are 1.47-3.03 m, the average non-dimensional lengths of the upstream face are 0.43-0.68 and the average lee slope angles are 0.26°-0.77°. The average wavelengths of secondary dunes are 4.71-9.18 m, the average wave heights are 0.24-0.55 m, the average non-dimensional lengths of the upstream face are 0.51-0.57 and the average lee slope angles are 7.51°-14.59°. The relationships between the geometrical properties values of the first-order and secondary dunes are similar. The wave heights are positively correlated with wavelength. There is no obvious relationship between the non-dimensional lengths of the upstream face and the wavelength. There is a negative correlation between the lee slope angles and the wavelengths. The wavelength, wave height, non-dimensional lengths of the upstream face and lee slope angles of the first-order dunes increase first and then decrease with the increase of the flow discharge, and the discharge of the critical point is about 1 500 m³/s. The wavelength, wave height and back water surface inclination of the secondary sand ridge are all increased with the increase of the flow rate, and there is no trend to change after the flow rate exceeding 1 500 m³/s. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rock & Mineral Analysis is the property of Editorial Board of Rock & Mineral Analysis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Mass Spectrometry Society is the property of Journal of Chinese Mass Spectrometry Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Erosion and deposition is depended mainly on oncoming water and sediment in the Lower Yellow River (LYR). It varies with changes of flow discharge and sediment concentration. The less sediment concentration is, the smaller ratio of deposition to oncoming sediment load is, and the larger water volume per unit for sediment transport will be. On the contrary, the higher sediment concentration is, the greater ratio and the less water volume will be. Under a circumstance of less water and more sediment, increasing shortage of water resources and contradiction between supply and demand, optimizing matches of oncoming flow and sediment and modeling floods of high efficient sediment transport can be carried out by reservoir regulation to reduce deposition and water volume for sediment transport. Based on typical floods of high efficient sediment transport in LYR, relationship between the ratio and water and sediment factors was established. A critical sediment concentration for erosion and deposition corresponding to discharge of 4,000 m3/s was 50 kg/m3. On the basis of flood and sediment transport pattern in the LYR, this paper analyzed the changes of water volumes per unit for sediment transport with changing of sediment concentration under restriction that the river channel maintained basically no deposition. Then, optimizing indices of flow and sediment for high efficient sediment transport were flood discharge of 4,000 m3/s, ratio of deposition to incoming sediment load of 0-15% and corresponding sediment concentration range from 50 to 75 kg/m3. [ABSTRACT FROM AUTHOR]

Copyright of Society: Chinese Journal of Sociology / Shehui is the property of Society: Chinese Journal of Sociology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ｂｅｄｆｏｒｍ ｉｓ ｖｅｒｙ ｉｍｐｏｒｔａｎｔ ｐａｒｔ ｔｏ ｒｅｓｉｓｔａｎｃｅ ｔｏ ｆｌｏｗ ａｎｄ ｓｅｄｉｍｅｎｔ ｔｒａｎｓｐｏｒｔ． Ｂａｓｅｄ ｏｎ ｔｈｅ ｂｅｄ ｌｏｎｇｉｔｕｄｉｎａｌ ｐｒｏｆｉｌｅｓ ａｎｄ ｂｅｄｆｏｒｍ ｍａｐｓ ｏｂｔａｉｎｅｄ ｂｙ Ｍｕｌｔｉ⁃Ｂｅａｍ Ｅｃｈｏ Ｓｏｕｎｄｉｎｇ （ＭＢＥＳ）， ｗｅ ｆｏｕｎｄ ｏｕｔ ｄｕｎｅｓ， ｔｒａｎｓｉｔｉｏｎ ａｎｄ ｕｐｐｅｒ ｐｌａｎｅ ｂｅｄ ｔｙｐｅｓ ｄｏｍｉｎａｔｅ ｗａｎｄｅｒｉｎｇ ｒｅａｃｈ ｏｆ ｔｈｅ ｌｏｗｅｒ Ｙｅｌｌｏｗ Ｒｉｖｅｒ ｗｉｔｈ ｔｈｅ ｃｏｎｔｒｏｌ ｆａｃｔｏｒ ａｎｄ ｂｅｄｆｏｒｍ ｄｉｓｃｒｉｍｉｎａｔｏｒ． Ａｓ ｔｈｅ ｗａｔｅｒ ｄｉｓｃｈａｒｇｅ ｉｎｃｒｅａｓｅｓ， ｂｅｄｆｏｒｍ ｄｅｖｅｌｏｐｓ ｆｒｏｍ ｄｕｎｅｓ ｔｏ ｔｒａｎｓｉｔｉｏｎ ａｎｄ ｕｐｐｅｒ ｐｌａｎｅ ｂｅｄｓ． Ｕｎｄｅｒ ｎａｔｕｒａｌ ｃｏｎｄｉｔｉｏｎ， ａｔ ｌｏｗ ｆｌｏｗ ｗｉｔｈ ｄｉｓｃｈａｒｇｅ ｌｅｓｓ ｔｈａｎ １ ５００ ｍ３ ／ ｓ， ｄｕｎｅｓ ａｒｅ ｄｏｍｉｎａｎｔ ａｎｄ ｔｈｅ ｒａｔｉｏ ｏｆ ｂｅｄｆｏｒｍ ｌｅｎｇｔｈ ｔｏ ｈｅｉｇｈｔ ｉｓ ｌａｒｇｅｒ， ５５０ ｏｎ ａｖｅｒａｇｅ． Ｗｈｅｎ ｔｈｅ ｈｉｇｈ ｆｌｏｗ ｄｉｓｃｈａｒｇｅ ｉｓ ｇｒｅａｔｅｒ ｔｈａｎ ２ ０００ ｍ３ ／ ｓ， ｕｐｐｅｒ ｐｌａｎｅ ｂｅｄｓ ａｒｅ ｄｏｍｉｎａｎｔ． Ｕｎｄｅｒ ｔｈｅ ｃｏｎｄｉｔｉｏｎ ｏｆ ｓｕｓｔａｉｎａｂｌｅ ｓｃｏｕｒｉｎｇ， ｔｗｏ ｓｃａｌｅｓ ｏｆ ｄｕｎｅｓ ａｒｅ ｆｏｕｎｄ ｗｈｅｎ ｌｏｗ ｆｌｏｗ ｗｉｔｈ ｄｉｓｃｈａｒｇｅ ｌｅｓｓ ｔｈａｎ １ ５００ ｍ３ ／ ｓ， ｉ．ｅ． ｔｈｅ ｓｍａｌｌ ｓｃａｌｅ ｄｕｎｅｓ ｗｉｔｈ ｂｅｄｆｏｒｍ ｈｅｉｇｈｔ ０．２－１．２ ｍ ｓｕｐｅｒｐｏｓｅｄ ｏｎ ｔｈｅ ｂｏｔｈ ｒｉｖｅｒ ｓｉｄｅ ａｎｄ ｌａｎｄ ｓｉｄｅ ｏｆ ｔｈｅ ｌａｒｇｅｒ ｓｃａｌｅ ｄｕｎｅｓ ｗｉｔｈ ｂｅｄｆｏｒｍ ｈｅｉｇｈｔ ２－３ ｍ． [ABSTRACT FROM AUTHOR]

The paper had a brief review on the studies of evolution and regulation of the Yellow River estuary. In response to the new situations like a significant decrease in the regime of the runoff to the Bohai Sea, the single-thread estuarine course having running for decades and the Xiaolangdi Reservoir having been put into operation, the authors put forward recent research objectives on channel evolution, coastline change, key technologies and schemes and measures. There are four key scientific and technological issues to be broken through: a) mechanisms of estuarine channel avulsing; b) responses of the coastal form to river runoff and ocean dynamics; c) multiple spatial and temporal scaled hybrid simulating of the estuarine course changing and; d) flow and sediment allocating of the estuary. There are six important research tasks, i.e. a) the estuarine channel avulsing process and its triggering mechanism; b) dynamic mechanisms of the channel evolution and index system of the course stabilization; c) the coastal evolving processes and its dynamic mechanism; d)multiple spatial and temporal scaled hybrid simulation of the estuarine evolution; e) technologies and demonstration of flow and sediment fluxes allocation of the estuary and; f) operating scheme and measures to stabilize the estuarine course for 100 years. The project achievements will provide technological support for integrated management of the Yellow River estuary and the construction of efficient ecological and economic zone of the delta. [ABSTRACT FROM AUTHOR]

A relatively narrow and deep channel can be formed, therefor visible change in channel width can be observed, at most of cross sections due to intensive channel adjustment during a hyperconcentrated flood in the lower Yellow River. The spatial and temporal distribution of sediment deposition was calculated for overbank hyperconcentrated floods by comparison of channel width after an overbank flood with that of non-overbank flood. Results shown that 59% of sediment that would be deposited in the main channel during non-overbank floods was removed by overbank hyperconcentrated floodsto the lower floodplain or floodplain. This indicated that overbank hyperconcentrated floods can reduce sediment deposition in the main channel comparing to non-overbank ones. Based on analysis of measured data, the relationship of channel contraction ratio, ranging from 15.5% to 44.0%, at overflow sections after floods to the channel width before floods was established. Correlation between sediment volume deposited on floodplain and the main hydraulic factors during overbank flooding period, as well as their physical meanings, was analyzed. Responding function of sediment volume deposited on floodplain to hydraulic factors was determined. A threshold index of flow and sediment load for floodplain deposition and main channel reforming during overbank hyperconcentrated floods was proposed, which was between 0.025 and 0.040. This research is significant to regulation of hyperconcentrated floods in the lower Yellow River. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)