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Design and Verification for Dual⁃mode CDFS and High⁃Load Compressor with a Large Flow Regulation Range
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作者 HUANG Lei ZHANG Jun +2 位作者 HAO Yuyang REN Hongkai CHU Wuli 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第5期632-644,共13页
This paper presents the design and verification of the dual-mode core driven fan stage(CDFS)and high-load compressor with a large flow regulation range.In view of the characteristics of large flow regulation range of ... This paper presents the design and verification of the dual-mode core driven fan stage(CDFS)and high-load compressor with a large flow regulation range.In view of the characteristics of large flow regulation range of the two modes and high average stage load coefficient,this paper investigates the design technology of the dual-mode high-efficiency compressor with a large flow regulation range and high-load compressor with an average stage load coefficient of 0.504.Building upon this research,the design of the dual-mode CDFS and four-stage compressor is completed,and three-dimensional numerical simulation of the two modes is carried out.Finally,performance experiment is conducted to verify the result of three-dimensional numerical simulation.The experiment results show that the compressor performance is improved for the whole working conditions by using the new design method,which realizes the complete fusion design of the CDFS and high-pressure compressor(HPC).The matching mechanism of stage characteristics of single and double bypass modes and the variation rule of different adjustment angles on performance are studied comprehensively.Furthermore,it effectively reduces the length and weight of compressor,and breaks through the key technologies such as high-load compressor with the average load factor of 0.504.These findings provide valuable data and a methodological foundation for the development of the next generation aeroengine. 展开更多
关键词 fusion design DUAL-MODE high-load compressor large flow regulation range
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Study on Different Size-fractionated Phytoplankton Assemblage Change in the Mesocosm Ecosystem
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作者 李涛 刘胜 +2 位作者 黄良民 简伟军 严岩 《Marine Science Bulletin》 CAS 2008年第2期58-67,共10页
A algal bloom process had been simulated via field mesocosm experiment, and the change of phytoplankton assemblage of different sizes in different growing phases had been studied. Nutrients addition could promote the ... A algal bloom process had been simulated via field mesocosm experiment, and the change of phytoplankton assemblage of different sizes in different growing phases had been studied. Nutrients addition could promote the growth of phytoplankton In the mesocosm of Prorocentrum donghaiense (M1) and the mesocosm of natural waters (M2), and the peaks of chlorophyll a were 112.79 mg/m and 235.60 mg/m, respectively. The restraining effect of nano-phytoplankton on pico-phytoplankton growth was stronger in M2 than in M1. When nutrients were abundant, the relative growth rate of diatom was higher than that of P. donghaiense, and they reached the peak quickly and then came to die out very fast. The decreasing of Si promoted diatom bloom to die out. 展开更多
关键词 Daya Bay MESOCOSM PHYTOPLANKTON Size fractionation Community change
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对洞庭湖平原地区城市防洪规划的思考
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作者 孟熊 黎昔春 +2 位作者 高碧 贺方舟 王维俊 《湖南水利水电》 2022年第4期59-62,共4页
在现有洞庭湖平原区城市防洪工程规划和建设中,城市防洪圈建设有“小围”和“大围”两种方案,防洪标准按照规范要求采用。文章对比分析了“小围”、“大围”方案的利弊、“二期治理”和城市防洪设计标准、设计水位及洞庭湖区水文特性,... 在现有洞庭湖平原区城市防洪工程规划和建设中,城市防洪圈建设有“小围”和“大围”两种方案,防洪标准按照规范要求采用。文章对比分析了“小围”、“大围”方案的利弊、“二期治理”和城市防洪设计标准、设计水位及洞庭湖区水文特性,提出沅江、南县、澧县、汉寿、安乡、华容等位于洞庭湖区重点垸内的县级城市防洪圈总体布局可采用“大围”方案,防洪标准直接采用洞庭湖“二期治理”的设计标准。研究成果对于洞庭湖平原区及类似地区的城市防洪规划和建设具有指导和借鉴意义。 展开更多
关键词 洞庭湖 重点垸 城市防洪 防洪标准 “小围” “大围”
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Influence range of emergency under special events based on CTM 被引量:6
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作者 陈茜 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期257-261,共5页
To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based ... To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events. 展开更多
关键词 traffic management special event EMERGENCY influence range cell transmission model (CTM)
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Compact Scanning Tunneling Microscope with Large Scale Searching Capability for Mmultidisciplinary Applications
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作者 孟文杰 王琦 +2 位作者 张晶 侯玉斌 陆轻铀 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期523-526,I0001,共5页
We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which ... We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which the Z coarse approach relies on a high simplic-ity friction-type walker (of our own invention) driven by an axially cut piezoelectric tube. The walker is vertically inserted in a piezoelectric scanner tube (PST) with its brim laying at on the PST end as the inertial slider (driven by the PST) for the XZ (sample plane) motion. The STM is designed to be capable of searching rare microscopic targets (defects, dopants, boundaries, nano-devices, etc.) in a macroscopic sample area (square millimeters) under extreme conditions (low temperatures, strong magnetic elds, etc.) in which it ts. It gives good atomic resolution images after scanning a highly oriented pyrolytic graphite sample in air at room temperature. 展开更多
关键词 Scanning tunneling microscope Large scale searching Air STM Electrochemical STM
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Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I. Development and Assessment of Chromatographic Conditions *1 被引量:4
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1998年第2期97-104,共8页
Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile ph... Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids. 展开更多
关键词 high performance liquid chromatography organic acids root exudates SOYBEAN
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Characteristics of microseismic b-value associated with rock mass large deformation in underground powerhouse caverns at different stress levels 被引量:10
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作者 LI Biao DING Quan-fu +3 位作者 XU Nu-wen DAI Feng XU Yuan QU Hong-lue 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期693-711,共19页
Rock mass large deformation in underground powerhouse caverns has been a severe hazard in hydropower engineering in Southwest China.During the development of rock mass large deformation,a sequence of fractures was gen... Rock mass large deformation in underground powerhouse caverns has been a severe hazard in hydropower engineering in Southwest China.During the development of rock mass large deformation,a sequence of fractures was generated that can be monitored using microseismic(MS)monitoring techniques.Two MS monitoring systems were established in two typical underground powerhouse caverns featuring distinct geostress levels.The MS b-values associated with rock mass large deformation and their temporal variation are analysed.The results showed that the MS bvalue in course of rock mass deformation was less than 1.0 in the underground powerhouse caverns at a high stress level while larger than 1.5 at a low stress level.Prior to the rock mass deformation,the MS b-values derived from both the high-stress and low-stress underground powerhouse caverns show an incremental decrease over 10%within 10 d.The results contribute to understanding the fracturing characteristics of MS sources associated with rock mass large deformation and provide a reference for early warning of rock mass large deformation in underground powerhouse caverns. 展开更多
关键词 underground powerhouse caverns rock mass large deformation stress level microseismic monitoring bvalue
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Short-and long-term results of endoscopic ultrasoundguided transmural drainage for pancreatic pseudocysts and walled-off necrosis 被引量:9
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作者 Yuto Watanabe Rintaro Mikata +5 位作者 Shin Yasui Hiroshi Ohyama Harutoshi Sugiyama Yuji Sakai Toshio Tsuyuguchi Naoya Kato 《World Journal of Gastroenterology》 SCIE CAS 2017年第39期7110-7118,共9页
AIM To evaluate the short-and long-term results of endoscopic ultrasound-guided transmural drainage(EUS-GTD) for pancreatic fluid collection(PFC) and identify the predictive factors of treatment outcome for walled-off... AIM To evaluate the short-and long-term results of endoscopic ultrasound-guided transmural drainage(EUS-GTD) for pancreatic fluid collection(PFC) and identify the predictive factors of treatment outcome for walled-off necrosis(WON) managed by EUS-GTD alone.METHODS We investigated 103 consecutive patients with PFC who underwent EUS-GTD between September 1999 and August 2015. Patients were divided into four groups as follows: WON(n = 40), pancreatic pseudocyst(PPC; n = 11), chronic pseudocyst(n = 33), and others(n = 19). We evaluated the short-and long-term outcomes of the treatment. In cases of WON, multiple logistic regression analyses were performed to identify the predictor variables associated with the treatment success. In addition, PFC recurrence was examined in patients followed up for more than 6 mo and internal stent removal after successful EUS-GTD was confirmed.RESULTS In this study, the total technical success rate was 96.1%. The treatment success rate of WON, PPC, chronic pseudocyst, and others was 57.5%, 90.9%, 91.0%, and 89.5%, respectively. Contrast-enhanced computed tomography using the multivariate logistic regression analysis revealed that the treatment success rate of WON was significantly lower in patients with more than 50% pancreatic parenchymal necrosis(OR = 17.0; 95%CI: 1.9-150.7; P = 0.011) and in patients with more than 150 mm of PFC(OR = 27.9; 95%CI: 3.4-227.7; P = 0.002).The recurrence of PFC in the long term was 13.3%(median observation time, 38.8 mo). Mean amylase level in the cavity was significantly higher in the recurrence group than in the no recurrence group(P = 0.02).CONCLUSION The reduction of WON by EUS-GTD alone was associated with the proportion of necrotic tissue and extent of the cavity. The amylase level in the cavity may be a predictive factor for recurrence of PFC. 展开更多
关键词 Endoscopic ultrasound-guided transmural drainage Pancreatic fluid collection Revised Atlanta Classification Walled-off necrosis
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Classification of wintertime large-scale tilted ridges over the Eurasian continent and their influences on surface air temperature 被引量:1
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作者 Da-Wei LIN Cholaw BUEH Zuo-Wei XIE 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第5期404-411,共8页
This study investigates the major patterns of large-scale tilted ridges(LSTRS)over the Eurasian continent and their connections with large-scale surface air temperature during boreal winter.A total number of 134 LSTR ... This study investigates the major patterns of large-scale tilted ridges(LSTRS)over the Eurasian continent and their connections with large-scale surface air temperature during boreal winter.A total number of 134 LSTR events with zonal extent exceeding 90°of longitude on the peak day are identified.Using self-organizing map(SOM),the LSTRs are classified into five clusters that are characterized by different spatial distributions and orientations.The leading two clusters are closely associated with extensive and persistent cold events over different places.Considering the first cluster,LSTRs extend from the Ural Mountains to Northeast Asia and are favorable for the amplification and southeastward extension of the Siberian high.Therefore,this cluster is closely associated with the occurrence of extensive and persistent cold events in china.In comparison with the first cluster,the LSTRs of second group are situated to the west,with starting points from the Kola Peninsula,and cause extensive and persistent cold events over Eastern Europe,central Asia,and central Siberia.The results suggest that the vertical coupling between LSTRs and the corresponding anomalous sea level pressure is crucial for the persistent cold temperature events associated with the leading two SOM clusters. 展开更多
关键词 Large-scale tilted ridges self-organizing map extensive and persistent cold event Siberian high
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Pressure from surrounding rock of three shallow tunnels with large section and small spacing 被引量:18
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作者 杨小礼 金启云 马军秋 《Journal of Central South University》 SCIE EI CAS 2012年第8期2380-2385,共6页
With the increasing traffic demand, the closely built three or more tunnels with large section play a significant role in the tunnel construction. However, the interaction among tunnels has important influences on the... With the increasing traffic demand, the closely built three or more tunnels with large section play a significant role in the tunnel construction. However, the interaction among tunnels has important influences on the security and economy of tunnel engineering, and the calculation of pressure from the surrounding rock during the excavation is one of the problems that need to be solved urgently. Based on the practical engineering of three tunnels, the load model of three tunnels was proposed in consideration of the interaction and excavation sequence between tunnels. In comparison with the load model of single tunnel, the construction mechanical characteristics of the three tunnels were analyzed. The results show that the rock pressure of three tunnels calculated by the current tunnel design code is not reliable, and the interaction force increases with the spacing between tunnels. 展开更多
关键词 three-tunnel model large section small clear spacing load model
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Urban Expansion in China Based on Remote Sensing Technology:A Review 被引量:7
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作者 ZHANG Zengxiang LIU Fang +9 位作者 ZHAO Xiaoli WANG Xiao SHI Lifeng XU Jinyong YU Sisi WEN Qingke ZUO Lijun YI Ling HU Shunguang LIU Bin 《Chinese Geographical Science》 SCIE CSCD 2018年第5期727-743,共17页
Urban areas and its evolution are important anthropogenic indicators and human ecological footprints, and play decisive roles in environmental change analysis, global geo-conditional monitoring, and sustainable develo... Urban areas and its evolution are important anthropogenic indicators and human ecological footprints, and play decisive roles in environmental change analysis, global geo-conditional monitoring, and sustainable development. China has the highest rate of urban expansion and has emerged as an urban expansion hotspot worldwide. In this paper, the progress of studies on Chinese urban expansion based on remote sensing technology are summarized and analyzed from the aspects of urban area definition, remotely sensed imagery applied in urban expansion, monitoring methods of urban expansion, and urban expansion applications. Existing issues and future directions of Chinese urban expansion are discussed and proposed. Results indicate that: 1) The fusion of multi-source remotely sensed imagery is imperative to meet the needs of urban expansion with various monitoring terms and frequencies on different scales and dimensions. 2) To guarantee the classification accuracy and efficiency and describe urban expansion and its influences on local land use simultaneously, the combination of visual interpretation and automatic classification is the tendency of future monitoring methods of urban areas. 3) Urban expansion data have become the prerequisite for recognizing the urban development process, excavating its driving forces, simulating and predicting the future development directions, and also is conducive to revealing and explaining urban ecological and environmental issues. 4) In the past decades, Chinese scholars have promoted the application of remote sensing technology in the urban expansion field, with data construction, methods and models developing from the quotation stage to improvement and innovation stage; however, an independent and consistent urban expansion data on the national scale with long-term and high-frequency(such as annual monitoring) monitoring is still lacking. 展开更多
关键词 urban areas urban expansion spatial resolution monitoring methods remote sensing China
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Tensile properties of as-deformed 2A50 aluminum alloy in semi-solid state 被引量:8
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作者 杜之明 陈刚 +1 位作者 柳君 谢水生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1597-1602,共6页
Tensile properties of as-deformed 2A50 aluminum alloy were investigated in the high temperature solid and semi-solid states. The results show that temperature has almost no effect on the maximum tensile stress between... Tensile properties of as-deformed 2A50 aluminum alloy were investigated in the high temperature solid and semi-solid states. The results show that temperature has almost no effect on the maximum tensile stress between 500 ℃ and 530 ℃, and the maximum tensile stress decreases rapidly when the temperature is above 532 ℃. The ductility decreases with increasing temperature and has an obvious fall when the temperature is above solidus temperature. This alloy almost has no ductility above 537 ℃, and cannot sustain tensile stress above 550℃. A brittle temperature range in which this alloy is prone to form microcracks was derived. The relation between microstructure, fraction solid and tensile properties were also investigated by examining the metallograph and fracture surface morphology of tested specimens, which could provide reference for forecasting the microcracks in this alloy occurring in semi-solid processing. 展开更多
关键词 tensile properties aluminum alloy SEMI-SOLID MICROCRACKS FORECAST
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Plastic zone distribution laws and its types of surrounding rock in large-span roadway 被引量:14
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作者 Li Chong Xu Jinhai +1 位作者 PanJianzhong Ma Chao 《International Journal of Mining Science and Technology》 2012年第1期23-28,共6页
In order to study the distribution laws and types of plastic zone of surrounding rock in large-span roadway, we analyzed the distribution laws with different spans and lateral pressures using FLAC3D numerical calcu- l... In order to study the distribution laws and types of plastic zone of surrounding rock in large-span roadway, we analyzed the distribution laws with different spans and lateral pressures using FLAC3D numerical calcu- lation software. Based on the roadway support difficulty and distribution laws of the plastic zone of sur- rounding rock, we defined the large-span roadway and classified the types of large-span rectangular roadways. As a result, the distribution laws of the plastic zone on surrounding rock in a rectangular roadway with different spans and lateral pressures were obtained. The results show that the area of the plastic zone on surrounding rock increased with the increase of the spans and lateral pressures, and the plastic zone was symmetrical to the center line of roadway. At λ=0.5, 1.0, 1.5, and 2.0, the plastic zone presented "addle- shape" distribution, "ellipse" distribution, "thin and high" distribution and "inverse trapezium" distribu- tion, respectively. In addition, we classified the roadways into four types according to the different lateral pressures and spans, including small-span, moderate-span, large-span and extreme-large-span roadways. 展开更多
关键词 Large-span roadway Plastic zone Distribution law TYPE
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A novel wide-range precision instrument for measuring three-dimensional surface topography
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作者 杨旭东 《Journal of Chongqing University》 CAS 2008年第1期52-57,共6页
We developed a measuring instrument that had wide range, high precision, small measuring touch force. The instrument for three-dimensional (3D) surface topography measurement was composed of a high precision displacem... We developed a measuring instrument that had wide range, high precision, small measuring touch force. The instrument for three-dimensional (3D) surface topography measurement was composed of a high precision displacement sensor based on the Michelson interference principle, a 3D platform based on vertical scanning, a measuring and control circuit, and an industrial control computer. It was a closed loop control system, which changed the traditional moving stylus scanning style into a moving platform scanning style. When the workpiece was measured, the lever of the displacement sensor returned to the balanced position in every sample interval according to the zero offset of the displacement sensor. The non-linear error caused by the rotation of the lever was, therefore, very small even if the measuring range was wide. The instrument can measure the roughness and the profile size of a curved surface. 展开更多
关键词 instrument circuit surface topography measurement error wide range precision instrument displacement sensor 3D platform
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Composition,Structure and Regeneration Dynamics of Olea ferruginea Royle Forests from Hindukush Range of Pakistan
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作者 NASRULLAH Khan FAYAZ Ali +1 位作者 KISHWAR Ali SHAHID Shaukat 《Journal of Mountain Science》 SCIE CSCD 2015年第3期647-658,共12页
Abstract" The abundance of Olea ferruginea in Malakand Division has been significantly reduced across its distribution range due to anthropogenic pressure in the recent past. A number of initiatives were taken for gr... Abstract" The abundance of Olea ferruginea in Malakand Division has been significantly reduced across its distribution range due to anthropogenic pressure in the recent past. A number of initiatives were taken for grafting this species to obtain better seeds for oil production, without the basic information on their ecology and management. To address this knowledge gap, we quantified the composition, structure and regeneration dynamics of Olea ferruginea forests in Malakand Division, Hindukush range of Pakistan. In the present study, five communities dominated by Oleaferruginea were identified using Ward's agglomerative cluster analysis. Total tree density ranged from 153-26o2 plants/ha, and basal area from 19.55 to 2353 m~ ha-1 with Olea having a relative density of 51% to 87% and basal area of 48% to 93%, respectively. The density of juveniles of the dominant and subordinate tree species were generally low which reflect their narrow distribution in the study area. Size-class distributions of O. ferruginea disclosed a bell-shaped pattern, indicating that forests were heavily exploited by local inhabitants in previous periods and recently by armed forces owing to security risks in the study area. The age (mean max. 300±34 years) and annual increment (3.2±1.2 years/cm) indicates that the species is long lived and generally slow growing among the different broad leaved species studied so far. However, the oldest trees can be found by the exploration of large diameter trees in the area. In addition, we found a stable linear relationship between the age and diameter (r2 = o.779), indicating that diameter is a good predictor of age for this broad leaved species. In view of its relatively slow growth, longevity and positive ring-width characteristics O. ferruginea seems to be a suitable choice for dendroecological and dendrochronological studies in lesser Himalayan and Hindukush ranges of Pakistan. The results obtained from this study may help in understanding the composition, structure and regeneration dynamics of other subtropical broad leaved species. 展开更多
关键词 Oleaferruginea Species composition Ward's agglomerative cluster analysis SEEDLING DENDROECOLOGY
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Solubilities of Nizatidine in Methanol+Water, Ethanol+Water and i-Propanol+Water from 273.15 to 303.15 K
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作者 李音 吕秀阳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期937-941,共5页
The solubilities of nizatidine in methanol + water, ethanol + water and i-propanol + water mixtures were determined in the temperature range from 273.15 K to 303.15 K at atmospheric pressure by a static analytical met... The solubilities of nizatidine in methanol + water, ethanol + water and i-propanol + water mixtures were determined in the temperature range from 273.15 K to 303.15 K at atmospheric pressure by a static analytical method. The general single model was used to correlate the experimental data, which fits the data very well. 展开更多
关键词 NIZATIDINE SOLUBILITY general single model
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ENCLOSURE EXPERIMENTS ON AND LACUSTRINE PRACTICE FOR ELIMINATING MICROCYSTIS BLOOM 被引量:5
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作者 刘建康 谢平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第2期113-117,共5页
Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East Lake) of Wuhan every summer from the 1970s up to 1984, but from 1985... Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East Lake) of Wuhan every summer from the 1970s up to 1984, but from 1985 up to now failed to occur there. The cause of its disappearance remained in obscurity until recently. In situ enclosure experiments in the lake for three years showed that the stocking of the filter-feeding silver carp (Hypophthalmichthys molitrix) and big-head carp (Aristichthys nobilis) played a decisive role in eliminating Microcystis bloom from the lake; but that recurrence of the bloom is possible under certain conditions. This paper presents the details and the results of enclosure experiments. The authors’ analysis of fish biomass data obtained by echo-sounding and the fishery production of the lake over the years, revealed that the recurrence of Microcystis bloom can be prevented so long as the combined biomass of silver carp and big-head carp remains at or exceeds 50 g per cubic meter of lakewater, as was the case in the lake’s 1985 fish yield of 1015 t. 展开更多
关键词 Microcystis bloom elimination enclosure experiments silver carp (Hypophthalmichthys molitrix) big-head carp (Aristichthys nobilis) fish-stocking practice of Donghu Lake
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Enhanced recovery for non-colorectal surgery 被引量:4
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作者 Gravante Gianpiero Elmussareh Muhammad 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第3期205-211,共7页
In recent years the advent of programs for enhanced recovery after major surgery (ERAS) has led to modifications of long-standing and well-established perioperative treatments. These programs are used to target factor... In recent years the advent of programs for enhanced recovery after major surgery (ERAS) has led to modifications of long-standing and well-established perioperative treatments. These programs are used to target factors that have been shown to delay postoperative recovery (pain, gut dysfunction, immobility) and combine a series of interventions to reduce perioperative stress and organ dysfunction. With due differences, the programs of enhanced recovery are generally based on the preoperative amelioration of the patient's clinical conditions with whom they present for the operation, on the intraoperative and postoperative avoidance of medications that could slow the resumption of physiological activities, and on the promotion of positive habits in the early postoperative period. Most of the studies were conducted on elective patients undergoing colorectal procedures (either laparotomic or laparoscopic surgery). Results showed that ERAS protocols significantly improved the lung function and reduced the time to resumption of oral diet, mobilization and passage of stool, hospital stay and return to normal activities. ERAS' acceptance is spreading quickly among major centers, as well as district hospitals. With this in mind, is there also a role for ERAS in non-colorectal operations? 展开更多
关键词 Enhanced recovery Length of stay Complications
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A New Upsurge in Global Seismicity
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作者 Deng Qidong 《Earthquake Research in China》 2013年第3期282-287,共6页
This paper studies the temporal and spatial distribution of great global earthquakes (Mw i〉 8.0) since 1900. We compare the two periods of upsurges of great earthquakes occurring in the middle of last century and b... This paper studies the temporal and spatial distribution of great global earthquakes (Mw i〉 8.0) since 1900. We compare the two periods of upsurges of great earthquakes occurring in the middle of last century and beginning of this century. The former period took place between 1950 and 1965 during which 13 great earthquakes (Mw I〉 8.0) occurred, including three events with moment magnitude greater than 9. 0. The largest magnitude in this period reached 9.6. The latter period starts from the beginning of this century. In less than 12 years, 15 great earthquakes have attacked the world with the largest magnitude being Mw 9. 1. On the basis of comparison between these two upsurges of global earthquake activity, we infer that the ongoing high level of earthquake activity may continue for another five years or so. Numerous great earthquakes (Mw I〉8. 0) and many large earthquakes (Mw6.0 ~ 7. 0) will occur globally in these five years. In addition, this paper also discusses the relationships between earthquake activity along the Sumatra segment of the Indian-Australia plate boundary and that in the Bayankala block in the middle of Qinghai-Tibetan plateau as well as in the blocks of the southern plateau. The results indicate that the Qinghai-Tibetan plateau, in particular its middle and southern parts, is a likely place for future earthquakes of magnitude over 7.0. 展开更多
关键词 Global seismicity Upsurge Seismic risk
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Evaluation of FAD-associated purse seine fishery reduction strategies for bigeye tuna (Thunnus obesus) in the Indian Ocean
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作者 童玉和 陈新军 +1 位作者 许柳雄 陈勇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期724-736,共13页
In the Indian Ocean, bigeye tuna supports one of the most important fisheries in the world. This fishery mainly consists of two components: longline and purse seine fisheries. Evidence of overfishing and stock depleti... In the Indian Ocean, bigeye tuna supports one of the most important fisheries in the world. This fishery mainly consists of two components: longline and purse seine fisheries. Evidence of overfishing and stock depletion of bigeye tuna calls for an evaluation of alternative management strategies. Using an age-structured operating model, parameterize dwith the results derived in a recent stock assessment,we evaluated the effectiveness of applying constant fishing mortality (CF) and quasi-constant fishing mortality (QCF) strategies to reduce fishing effort of purse seining with fish aggregating devices (FADs) at different rates. Three different levels of productivity accounted for the uncertainty in our understanding of stock productivity. The study shows that the results of CF and QCF are similar. Average SSB and catchduring simulation years would be higher if fishing mortality of FAD-associated purse seiningwas reduced rapidly. The banning or rapid reduction of purse seining with FAD resulted in a mean catch, and catch in the last simulation year, higher than that of the base case in which no change was made to the purse seine fishery. This could be caused by growth overfishing by purse seine fisheries with FADs according to the per-recruit analysis. These differences would be more obvious when stock productivity was low. Transferring efforts of FAD-associated purse seining to longline fisheries is also not feasible.Our study suggests that changes are necessary to improve the performance of the current management strategy. 展开更多
关键词 Thunnus obesus purse seine fishing aggregating device simulation Indian Ocean
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