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Food web structure and trophic levels in a saltwater pond sea cucumber and prawn polyculture system

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Acta Oceanologica Sinica 2016年第4期35卷 58-62页

作者： GUO Kai ZHAO Wen WANG Shan liu baozhan ZHANG Peng Key Laboratory of Hydrobiology in Liaoning Province Dalian Ocean University Offshore Environment Services Co. Ltd.

The food sources of aquacultured Apostichopus japonicus and the trophic levels of organisms in a sea cucumber（A. japonicus） and prawn（Penaeus japonica） polyculture system in a saltwater pond in Zhuanghe, Liaoning Province were examined using carbon and nitrogen stable isotopes. Across organisms, δ13C ranged from（–25.47±0.20）‰ to（–16.48±0.17）‰（mean±SD）, and δ15N ranged from（4.23±0.49）‰ to（12.44±0.09）‰. The δ13C and δ15N contents of A. japonicus, P. japonica and Fenneropenaeus chinensis were comparatively higher than those of other organisms. Values of δ13C and δ15N revealed that P. japonica, Hemigrapsus sanguineus and Neomysis japonica comprised the largest component of the diet of A. japonicus. The mean trophic level of the organisms in this saltwater pond polyculture system was（2.75±0.08）. P. japonica, A. japonicus, F. chinensis,Synechogobius hasta and Neomysis japonica were in the 3rd trophic level（2–3）; jellyfish, H. sanguineus and zooplankton were in the 2nd trophic level（1–2）; and Enteromorpha prolifera, benthic microalgae, periphyton and suspended matter primarily consisting of phytoplankton, bacteria and humus were in the primary trophic level（0–1）.

关键词： Aposticbopus japonicas Penaeus japonica stable isotopes food web structure diet composition trophic level

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匙吻鲟肌肉与软骨营养成分分析

北京农业（下旬刊） 2010年第5期 12-14页

作者：殷守仁刘保占刘磊大连水产学院辽宁省水生生物重点实验室辽宁大连116023 北京市水产技术推广站北京100012

分析了匙吻鲟肌肉和软骨常规营养成分(蛋白质、脂肪、水分、灰分、钙和磷)的含量,对蛋白质的17种氨基酸和主要微量元素进行测定。结果表明:匙吻鲟肌肉组织中水分含量为76.50%,粗蛋白含量为15.40%,脂肪含量为5.50%,灰分为1.01%,氨基酸含... 详细信息

分析了匙吻鲟肌肉和软骨常规营养成分(蛋白质、脂肪、水分、灰分、钙和磷)的含量,对蛋白质的17种氨基酸和主要微量元素进行测定。结果表明:匙吻鲟肌肉组织中水分含量为76.50%,粗蛋白含量为15.40%,脂肪含量为5.50%,灰分为1.01%,氨基酸含量最高为谷氨酸,含量最低的为色氨酸;软骨中钠、钾和钙含量比较高,氨基酸含量前3位的是甘氨酸、谷氨酸和亮氨酸,排在最后的是色氨酸和胱氨酸。

关键词：匙吻鲟肌肉软骨营养成分氨基酸

深基坑开挖中考虑时空效应的土压力计算方法研究

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四川建筑科学研究 2014年第4期40卷 153-155页

作者：邾祝融刘影刘保战华东管道设计研究院江苏徐州221008

针对土体自身特性及深基坑开挖工程的特点,总结分析了土压力随位移和时间的变化规律,初步讨论了考虑位移效应和时间效应的土压力计算公式.考虑基坑工程位移和时间的耦合作用,运用耦合理论,提出了基于时空效应的土压力计算方法.实际工程... 详细信息

针对土体自身特性及深基坑开挖工程的特点,总结分析了土压力随位移和时间的变化规律,初步讨论了考虑位移效应和时间效应的土压力计算公式.考虑基坑工程位移和时间的耦合作用,运用耦合理论,提出了基于时空效应的土压力计算方法.实际工程分析结果表明,该方法比传统计算方法更接近实测值,误差仅为传统方法误差的1/5～ 1/4.该方法完善了基坑支护设计理论,对基坑设计与施工具有一定的指导作用.

关键词：基坑开挖时空效应土压力耦合

基于生态保护红线的海洋油气勘探开发用海矛盾初探

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海洋经济 2021年第6期11卷 62-67页

作者：王茂君刘保占生态环境部海河流域北海海域生态环境监督管理局生态环境监测与科学研究中心天津300170

加大海上油气勘探开发力度是保障国家能源安全的重要措施。当前,海洋油气勘探开发用海与现行海洋生态保护红线存在矛盾冲突。本文给出了两者矛盾识别及解决的思路,提出了相应对策建议,以期为新一轮生态保护红线评估调整提供借鉴思路。

关键词：海洋油气勘探开发海洋生态保护红线矛盾冲突

Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC ***,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC ***,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is ***,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind *** simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during ***:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during ***:Sixteen RCTs with a cumulative sample size of 1178 cases were *** these,964 patients were included in the *** Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low ***:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively ***,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

Stochastic Unit Commitment with High-Penetration Offshore Wind Power Generation in Typhoon Scenarios

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 535-546页

作者： Yanqi liu Dundun liu Hongcai Zhang State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao 999078China University of Macao Zhuhai UM Science and Technology Research Institute ZhuhaiChina

To tackle the energy crisis and climate change,wind farms are being heavily invested in across the *** China's coastal areas,there are abundant wind resources and numerous offshore wind farms are being *** secure operation of these wind farms may suffer from typhoons,and researchers have studied power system operation and resilience enhancement in typhoon ***,the intricate movement of a typhoon makes it challenging to evaluate its spatial-temporal *** published papers only consider predefined typhoon trajectories neglecting *** address this challenge,this study proposes a stochastic unit commitment model that incorporates high-penetration offshore wind power generation in typhoon *** adopts a data-driven method to describe the uncertainties of typhoon trajectories and considers the realistic anti-typhoon mode in offshore wind farms.A two-stage stochastic unit commitment model is designed to enhance power system resilience in typhoon *** formulate the model into a mixed-integer linear programming problem and then solve it based on the computationally-efficient progressive hedging algorithm(PHA).Finally,numerical experiments validate the effectiveness of the proposed method.

关键词： Unit commitment two-stage stochastic programming offshore wind farm typhoon

Devolatilization of high viscous fluids with high gravity technology

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Chinese Journal of Chemical Engineering 2024年第7期71卷 249-257页

作者： Jibing Qi Youzhi liu Yandong liu Taiyuan University Taiyuan 030032China Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

Volatile organic compounds(VOCs)are generally toxic and harmful substances that can cause health and environmental *** removal of VOCs from polymers has become a key *** effective devolatilization to remove VOCs from high viscous fluids such as polymer is necessary and is of great *** this study,the devolatilization effect of a rotating packed bed(RPB)was studied by using polydimethylsiloxane as the viscous fluid and acetone as the *** devolatilization rate and liquid phase volume(KLa)have been *** results indicated that the optimum conditions were the high-gravity factor of 60,liquid flow rate of 10 L·h^(-1),and vacuum degree of 0.077 *** dimensionless correlation of KLa was established,and the deviations between predicted and experimental values were less than±28%.The high-gravity technology will result in lower mass transfer resistance in the devolatilization process,enhance the mass transfer process of acetone,and improve the removal effect of *** work provides a promising path for the removal of volatiles from polymers in combination with high-gravity *** can provide the basis for the application of RPB in viscous fluids.

关键词： High-gravity technology Devolatilization rate High viscous fluid Volatile organic compounds(VOCs)