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Experimental and Numerical Investigations of the Hydrodynamic Characteristics, Twine Deformation, and Flow Field Around the Netting Structure Composed of Two Types of Twine Materials for Midwater Trawls

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Journal of Ocean University of China 2021年第5期20卷 1215-1235页

作者： THIERRY Bruno Nyatchouba Nsangue TANG Hao ACHILE Njomoue Pandong XU Liuxiong ZHOU Cheng hu Fuxiang College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai 201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai 201306China Laboratory E3M National High Polytechnic School of DoualaUniversity of DoualaDouala 2701Cameroon Faculty of Marine Science Tokyo University of Marine Science and TechnologyMinatoTokyo 108-8477Japan

Nettings are complex flexible structures used in various *** the hydrodynamic characteristics,de-formation,and the flow field around nettings is important to design successful fishing *** study investigated the hydrodynamic characteristics and deformation of five nettings made of polyethylene and nylon materials in different attack angles through numeri-cal simulation and physical model *** numerical model was based on the one-way coupling between computational fluid dynamics(CFD)and large deflection nonlinear structural ***-Stokes equations were solved using the finite volume ap-proach,the flow was described using the k-ωshear stress turbulent model,and the large deflection structural dynamic equation was derived using a finite element approach to understand the netting deformation and nodal *** porous media model was chosen to model the nettings in the CFD *** data were compared with the experimental results of the physical model to validate the numerical *** showed that the numerical data were compatible with the experimental data with an average relative error of 2.34%,3.40%,6.50%,and 5.80%in the normal drag coefficients,parallel drag coefficients,inclined drag coefficients,and inclined lift coefficients,*** hydrodynamic forces of the polyethylene and nylon nettings decreased by approxi-mately 52.56%and 66.66%,respectively,with decreasing net *** drag and lift coefficients of the nylon netting were appro-ximately 17.15%and 6.72%lower than those of the polyethylene netting.A spatial development of turbulent flow occurred around the netting because of the netting ***,the flow velocity reduction downstream from the netting in the wake region in-creased with increasing attack angle and net *** addition,the deformation,stress,and strain on each netting increased with in-creasing solidity ratio.

关键词： netting k-ωshear stress turbulent(SST)model porous media model large deflection nonlinear structural model hydrodynamic characteristics

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基于响应面法的轴流泵结构参数匹配研究

水电能源科学 2024年第9期42卷 171-175页

作者：赵万勇胡炳彤于帅潘江龙张宇翔兰州理工大学能源与动力工程学院甘肃兰州730050

为减小叶轮出口到导叶进口之间的水力损失,选取比转速为1296的轴流泵作为研究对象,通过响应面分析和数值模拟相结合的方法,研究叶轮、导叶不同结构参数的匹配关系对水力效率的影响。将叶轮出口角修正系数ξ、导叶进口冲角Δβ、轴向间距... 详细信息

为减小叶轮出口到导叶进口之间的水力损失,选取比转速为1296的轴流泵作为研究对象,通过响应面分析和数值模拟相结合的方法,研究叶轮、导叶不同结构参数的匹配关系对水力效率的影响。将叶轮出口角修正系数ξ、导叶进口冲角Δβ、轴向间距S作为优化设计变量,泵的效率作为响应值,建立了优化变量与水力效率之间的多元二次回归方程。研究结果表明,导叶进口冲角Δβ对轴流泵性能的影响最大,其次为轴向间距S,叶轮出口角修正系数ξ的影响最小。此外,导叶进口冲角Δβ与叶轮出口角修正系数ξ均与轴向间距S有明显交互作用。依据优化变量的取值范围,得到了最优参数组合为ξ=1.2,Δβ=-0.7°,S=8.5 mm。优化后的轴流泵在设计工况下扬程提高了0.61 m,效率提高了2.6%。研究结果为进一步提升轴流泵水力性能提供了参考。

关键词：轴流泵响应面模型结构参数水力性能

番茄中功能物质的特性及不同加工方式对其品质的影响

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寒旱农业科学 2024年第10期3卷 883-893页

作者：张莉马彦霞陶兴林胡志峰甘肃省农业科学院蔬菜研究所甘肃兰州730070

番茄是人们餐桌上的美味之一,受到世界范围内消费者的广泛喜爱。番茄具有很高的营养价值,除含有常规营养素外,番茄所含大量具有抗氧化活性的酚类和黄酮类物质于人体健康十分有益,可以有效预防疾病的发生。番茄水分含量高,导致采后易变... 详细信息

番茄是人们餐桌上的美味之一,受到世界范围内消费者的广泛喜爱。番茄具有很高的营养价值,除含有常规营养素外,番茄所含大量具有抗氧化活性的酚类和黄酮类物质于人体健康十分有益,可以有效预防疾病的发生。番茄水分含量高,导致采后易变质且鲜食期短,因此多数需加工后进入市场,但在加工过程中往往会造成番茄在外观、质地、香气和功能性物质的大量损耗。随着人们生活水平的不断提高,番茄营养功能类物质在加工过程的大量损耗与人们追求营养健康饮食方式的诉求不符,因此新式非传统加工方式近年来大量出现,包括超高压处理、超声处理和脉冲电场处理等。本文系统阐述了番茄中的生物组成成分和活性成分,根据不同活性成分所具有的潜在益生或预防疾病特性来综合分析番茄的营养特性和益生特性,并深入探讨不同加工方式对番茄营养品质的影响。

关键词：番茄功能成分健康特性加工方式非热处理方式

高温条件下盐酸雷尼替丁中N-亚硝基二甲胺及其前体化合物二甲胺和亚硝酸盐研究

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中南药学 2024年第8期22卷 2191-2197页

作者：杜冬生钟鸿姣胡杰吴静刘永安徽师范大学生命科学学院安徽芜湖241000 芜湖市食品药品检验中心安徽芜湖241007 安徽省食品药品检验研究院合肥230051

目的考察盐酸雷尼替丁原料药中的N-亚硝基二甲胺(NDMA)及其前化合物二甲胺(DMA)和亚硝酸盐(NO_(2)^(-))在高温条件下含量变化。方法盐酸雷尼替丁原料药分别置于有氧和无氧环境中,在40℃和60℃的条件下破坏5、10和30 d。采用超高效液相... 详细信息

目的考察盐酸雷尼替丁原料药中的N-亚硝基二甲胺(NDMA)及其前化合物二甲胺(DMA)和亚硝酸盐(NO_(2)^(-))在高温条件下含量变化。方法盐酸雷尼替丁原料药分别置于有氧和无氧环境中,在40℃和60℃的条件下破坏5、10和30 d。采用超高效液相色谱串联质谱法(UPLC-MS/MS)、阳离子和阴离子色谱法,分别测定破坏后样品中NDMA、DMA和NO_(2)^(-)的含量。结果建立的3种检测方法的专属性、灵敏度、线性、回收率和重复性均满足要求。在有氧和无氧环境中,60℃破坏的盐酸雷尼替丁样品中3种物质的含量均高于40℃;另外,在有氧条件下,3种物质的含量也明显高于相应的无氧条件,其中第30日,60℃有氧条件下NDMA、DMA和NO_(2)^(-)分别增长至1.92、55.50和44.76μg·g-1。结论温度和氧气是盐酸雷尼替丁产生NDMA及其前体化合物DMA和NO_(2)^(-)的重要因素;同时,间接验证盐酸雷尼替丁产生NDMA可能的机制为首先降解生成DMA和NO_(2)^(-),并进一步反应生成NDMA。本研究可为盐酸雷尼替丁贮存条件设置和质量标准提升提供参考。

关键词：超高效液相色谱串联质谱法离子色谱法盐酸雷尼替丁 N-亚硝基二甲胺二甲胺亚硝酸盐高温破坏

精神分裂症患者照顾者负担评估工具的研究进展

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神经疾病与精神卫生 2024年第4期24卷 260-265页

作者：姚灏胡前英李坤梅徐一峰上海交通大学附属精神卫生中心 200030 上海童创未来精神科门诊部 201804

精神分裂症会给患者的照顾者带来沉重的负担。照顾者负担不仅会影响照顾者的身心健康,还会影响其照顾质量,从而影响精神分裂症患者的长期预后。目前,针对精神分裂症患者的照顾者负担,国际上已有许多评估工具(包括普适性评估工具和特异... 详细信息

精神分裂症会给患者的照顾者带来沉重的负担。照顾者负担不仅会影响照顾者的身心健康,还会影响其照顾质量,从而影响精神分裂症患者的长期预后。目前,针对精神分裂症患者的照顾者负担,国际上已有许多评估工具(包括普适性评估工具和特异性评估工具),本文从内容、特点、应用情况等不同方面对这些工具进行综述及比较,分析评估工具存在的不足并提出建议,以期为国内开展精神分裂症患者照顾者负担的评估及干预提供指导。

关键词：精神分裂症照顾者负担评估工具量表综述

抗γ干扰素自身抗体阳性的非结核分枝杆菌病患者的临床特征分析

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中华传染病杂志 2024年第4期42卷 233-238页

作者：秦志杰林思然汪婷杨文灿胡潇倩王士勇苏然陈沛冬邵凌云复旦大学附属华山医院感染科上海市传染病与生物安全应急响应重点实验室国家传染病医学中心上海200040 复旦大学附属华山医院静安分院感染科上海200040

目的分析抗γ干扰素自身抗体阳性的非结核分枝杆菌(NTM)病患者的临床特征。方法纳入2021年7月至2023年8月复旦大学附属华山医院和复旦大学附属华山医院静安分院诊治的43例人类免疫缺陷病毒阴性的NTM病成年患者,收集患者的临床资料和菌... 详细信息

目的分析抗γ干扰素自身抗体阳性的非结核分枝杆菌(NTM)病患者的临床特征。方法纳入2021年7月至2023年8月复旦大学附属华山医院和复旦大学附属华山医院静安分院诊治的43例人类免疫缺陷病毒阴性的NTM病成年患者,收集患者的临床资料和菌种检出情况。通过酶联免疫吸附测定法检测血浆抗γ干扰素自身抗体水平,并将患者分为抗体阳性组与抗体阴性组。回顾性分析两组患者的临床特征和实验室检查结果。统计学比较采用独立样本t检验、曼-惠特尼U检验、χ^(2)检验。采用多因素logistic回归分析判断NTM病患者抗γ干扰素自身抗体阳性的相关因素。结果43例患者中,抗γ干扰素自身抗体阳性患者13例(30.2%),抗体阴性患者30例(69.8%)。抗体阳性组中NTM播散性感染[9/13比30.0%(9/30)]和合并细菌感染[5/13比6.7%(2/30)]的患者比例均高于抗体阴性组,差异均有统计学意义(χ^(2)=5.74、6.73,均P350×10^(9)/L的比例均高于抗体阴性组,白球比水平低于抗体阴性组,差异均有统计学意义(t=2.42、3.02,χ^(2)=9.77,t=3.66,均P350×10^(9)/L(OR=14.31,95%CI 1.91~107.04)为判断抗γ干扰素自身抗体阳性的危险因素(均P350×10^(9)/L)时建议进行抗γ干扰素自身抗体检测。

关键词：非结核分枝杆菌抗γ干扰素自身抗体临床特征

Reliability Evaluation of Electricity-heat Integrated Energy System with Heat Pump

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CSEE Journal of Power and Energy Systems 2018年第4期4卷 425-433页

作者： Shenxi Zhang Min Wen Haozhong Cheng Xiao hu Guodong Xu School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Integrated energy system(IES)has the advantages of improving the efficiency of energy utilization and promoting the consumption of renewable *** is of great importance to evaluate the reliability of an *** paper proposes a novel reliability evaluation method for the electricity-heat IES with heat ***,the load-point reliability indices and systemlevel reliability indices are defined according to the characteristics of electricity-heat ***,the model of maximum output heat power of heat pump at the user-side considering the safety criterion of distribution network is established,and the stepvaried repeated power flow method is applied to solve the ***,the reliability evaluation procedure of electricityheat IES with heat pump based on the Monte Carlo simulation is *** studies are carried out on the electricityheat IES of an industrial park,and the results show that the configuration site,capacity and coefficient of performance of heat pump as well as the security constraints of distribution network can significantly affect the reliability indices.

关键词： Electricity-heat integrated energy system heat pump Monte Carlo simulation reliability evaluation security constraints

Design of motor-driven precision seed-metering device with improved fuzzy PID controller for small peanut planters

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International Journal of Agricultural and Biological Engineering 2023年第1期16卷 136-144页

作者： Yan Yu Yanrui hu Shuqi Shang Linsong Diao Ruchao Ge Xing Zhang College of Mechanical and Electrical Engineering Qingdao Agricultural UniversityQingdao 266109ShandongChina

Traditional passive ground wheel drive of peanut planters has displayed poor high-speed seeding performance and the slippage caused in case of sticky and wet *** this,an integrated electric-driven precision seed metering device and controller were designed,which features the application of improved fuzzy PID *** on a small peanut planter with one ridge width and duplicate rows,the servo motor drive is used to replace the traditional passive ground *** addition,the satellite speed measurement is employed to complete the electric driving and controlling modification of the seed meter and precise seeding control.A working process mathematical model for the peanut metering device was established to conduct motor speed and field tests which aim at comparing performances between the conventional and the improved fuzzy PID *** motor speed trial shows that the average error of the actual speed of the improved fuzzy PID motor was±1 rad/min,and the coefficient of variation was less than 1%.Against the conventional one,it can better suppress overshoot and improve the response *** stable output speed can still be obtained even in case of step *** tests show that when working at medium and low speeds,the qualified rate of plant spacing was greater than 98%,and the rate of missed sowing is<2%;while working at high speed,the qualified rate was greater than 94%,and the rate of missed sowing was less than 4%.The average plant spacing qualification rate of the seed device increased by 6.72%;compared with other electric-driven peanut seed meters,the plant spacing qualification rate increased by 4%during high-speed *** summary,this study has provided an effective technical reference for high-speed precision planting of peanuts.

关键词： peanut planter precision seeding control system improved fuzzy PID

Exercise induces tissue hypoxia and HIF-1α redistribution in the small intestine

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Journal of Sport and Health Science 2020年第1期9卷 82-89页

作者： Die Wu Wei Cao Dao Xiang Yi-Ping hu Beibei Luo Peijie Chen School of Kinesiology Shanghai University of SportShanghai 200438China Department of Diving Medicine Naval Medical Research InstituteSecond Military Medical UniversityShanghai 200432China Department of Cell Biology Second Military Medical UniversityShanghai 200432China

Background:Exercise induces blood flow redistribution among tissues,leading to splanchnic *** epithelial cells are positioned between the anaerobic lumen and the highly metabolic lamina propria with an oxygen ***-inducible factor(HIF)-la is pivotal in the transcriptional response to the oxygen ***:In this study,the pimonidazole hydrochloride staining was applied to observe the tissue hypoxia in different organs,which might be affected by the blood flow *** HIF-la luciferase reporter ROSA26 oxygen-dependent degradation domain(ODD)-Luc/^+mouse model(ODD domain-Luc;female,n=3-6/group) was used to detect the HIF-la expression in the *** used 3 swimming models:moderate exercise for 30 min,heavy-intensity exercise bearing 5% bodyweight for 1.5 h,and long-time exercise for 3 ***:We found that 1 session of swimming at different intensities could induce tissue hypoxia redistribution in the small intestine,colon,liver and kidney,but not in the spleen,heart,and skeletal *** data showed that exercise exacerbated the extent of physiological hypoxia in the small ***,using ODD-Luc mice,we found that moderate exercise increased the in vivo HIF-1α level in the small *** postexercise HIF-1α level was gradually decreased in a time-dependent ***,the redistribution of tissue hypoxia and the increase of HIF-la expression were not related to the exercise intensity and ***:This study provided evidence that the small intestine is the primary target organ for exercise-induced tissue hypoxia and HIF-la redistribution,suggesting that HIF-1α may be a potential target for the regulation of gastrointestinal functions after exercise.

关键词： Blood flow redistribution Hypoxia-inducible factor-1α ODD-Luc Pimonidazole HCl Swimming