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Influence of Different Transition Modes on the Performances of a Hydraulic Turbine

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Fluid Dynamics & Materials Processing 2023年第10期19卷 2481-2497页

作者： fengxia shi Yucai Tang Dedong Ma Xiangyun shi Guangbiao Zhao School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Key Laboratory of Fluid Machinery and Systems of Gansu Lanzhou730050China

In order to analyze the response of a hydraulic turbine to a variation in the operating conditions,different laws of variation in time of the massﬂow rate have been considered.After validating the overall numerical framework through comparison with relevant experiments,the performances of the considered turbine have been analyzed from aﬂuid-dynamic point of view.The results show that different time proﬁles of the massﬂow rate(in this work,for simplicity,referred to as“transition functions”)have a varying inﬂuence on the transient behavior of the turbine.When a quadratic function is considered for the case of largeﬂow,the transient head and torque increase gradually with time,theﬂuctuation amplitude of the transient hydraulic efﬁciency at the main frequency is the largest,and theﬂuctuation amplitude of the radial force is the smallest.For the smallﬂow case,the time proﬁle with exponential nature leads to the best results.The transient head and torque decrease gradually with time,the pulsation amplitude of the transient hydraulic efﬁciency is the largest at the main frequency,and the pulsation amplitude of the radial force is the smallest.

关键词： Transition functions hydraulic turbine transition process radial resultant force

Study on Energy Conversion Characteristics in Volute of Pump as Turbine

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Fluid Dynamics & Materials Processing 2021年第1期17卷 201-214页

作者： Senchun Miao Hongbiao Zhang fengxia shi Xiaohui Wang Xijin Ma School of Energy and Power Engineering Lanzhou University of TechnologyLanzhouChina Jiangsu Shuangda Pump Valve Group Co. Ltd.JingjiangChina

A volute is a curved funnel with cross-sectional area increasing towards the discharge port.The volute of a centrifugal pump is the casing hosting the fluid being pumped by the impeller.In Pump-as-turbine devices(PAT),vice versa the volute plays the role of energy conversion element.In the present analysis,this process is analyzed using CFD.The results show that in the contraction section of volute the conversion between dynamic pressure energy and static pressure energy essentially depends on the reduction of flow area,while in the spiral section,frictional losses also play a significant role.From the throat to the end of the volute,the flow decreases in a wave-like manner.

关键词： Pump as turbine volute energy conversion static pressure power dynamic pressure power

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W_(n)□P_(m)的r-hued染色

山东大学学报（理学版） 2024年第2期59卷 59-64页

作者：史雅馨刘凤霞蔡华新疆大学数学与系统科学学院新疆乌鲁木齐830046 昌吉学院数学与数据科学学院新疆昌吉831199

图G的(k,r)-染色是对图G用k种颜色进行正常染色,使得图G任一点v的邻点至少染min{r,d(v)}种不同的颜色。使图G有一个(k,r)-染色的最小的整数k称为图G的r-hued色数,用χ_(r)(G)来表示。图G和H的笛卡尔乘积图记为GH,其顶点集为V(G)×V(H),(... 详细信息

图G的(k,r)-染色是对图G用k种颜色进行正常染色,使得图G任一点v的邻点至少染min{r,d(v)}种不同的颜色。使图G有一个(k,r)-染色的最小的整数k称为图G的r-hued色数,用χ_(r)(G)来表示。图G和H的笛卡尔乘积图记为GH,其顶点集为V(G)×V(H),(u_(1),v_(1))与(u_(2),v_(2))相邻当且仅当u_(1)=u_(2),v_(1)v_(2)∈E(H)或v_(1)=v_(2),u_(1)u_(2)∈E(G)。确定了W_(n)□P_(m)的r-hued色数。

关键词： (k,r)-染色 r-hued色数笛卡尔乘积图

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弯萼金丝桃总黄酮提取及抗氧化、降糖活性

精细化工 2024年第5期41卷 1050-1059,1083页

作者：王俊龙蔺永刚陈凤霞时文盼陈禹伊犁师范大学新疆生物质资源清洁转化与高值化利用重点实验室新疆伊宁835000 新疆医科大学药学院新疆乌鲁木齐830017

通过单因素和响应面实验探究5种提取工艺(超声辅助提取、酸解提取、酶解提取、热水提取、热醇提取)对弯萼金丝桃总黄酮(TF)提取量的影响。采用HPLC测定并分析主要黄酮苷元的分布及含量,并进一步考察了TF与体外抗氧化活性〔1,1-二苯基-2... 详细信息

通过单因素和响应面实验探究5种提取工艺(超声辅助提取、酸解提取、酶解提取、热水提取、热醇提取)对弯萼金丝桃总黄酮(TF)提取量的影响。采用HPLC测定并分析主要黄酮苷元的分布及含量,并进一步考察了TF与体外抗氧化活性〔1,1-二苯基-2-三硝基苯肼自由基(DPPH•)清除能力、2,2'-联氮-双(3-乙基苯并噻唑啉-6-磺酸)二铵盐自由基(ABTS•)清除能力、•OH清除能力、还原能力〕的相关性及对α-葡萄糖苷酶的体外降糖能力。结果表明,超声辅助提取TF提取量最高。响应面优化最佳提取工艺为:超声提取温度68℃、提取时间23 min、乙醇体积分数24%、溶剂与样品的液料比(mL∶g)63∶1。在该条件下,TF提取量为34.85 mg RT/g〔以每克弯萼金丝桃中黄酮类化合物相当于芦丁(RT)的质量表示〕。经HPLC鉴定出TF中含有7种主要黄酮类化合物,其中,含量最高的为槲皮素-3-O-洋槐糖-7-O-鼠李糖苷和槲皮素,分别为3.897和2.874 mg/g;TF质量浓度与DPPH•清除能力、ABTS•清除能力、•OH清除能力、还原能力呈显著正相关,TF对α-葡萄糖苷酶的降糖能力可达到92.6%。

关键词：弯萼金丝桃总黄酮提取工艺高效液相色谱抗氧化活性降糖活性中药现代化技术

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骨外尤因肉瘤的影像学表现

中国医学影像学杂志 2024年第6期32卷 599-603页

作者：史凤霞刘宇刘鹏谭显政范立新湖南省人民医院放射科湖南长沙410005 湖南省人民医院病理科湖南长沙410005

目的探讨骨外尤因肉瘤(EES)的影像学表现和临床病理特征。资料与方法回顾性分析2014年1月—2023年1月湖南省人民医院经手术病理证实的14例EES的临床、影像学资料及病理特征,其中7例行CT检查(增强5例),9例行MRI检查(增强8例)。结果病... 详细信息

目的探讨骨外尤因肉瘤(EES)的影像学表现和临床病理特征。资料与方法回顾性分析2014年1月—2023年1月湖南省人民医院经手术病理证实的14例EES的临床、影像学资料及病理特征,其中7例行CT检查(增强5例),9例行MRI检查(增强8例)。结果病灶位于脊柱旁3例,右咽旁间隙1例,纵隔1例,左大腿1例,左耻骨旁软组织1例,腹膜后1例,盆腔1例,前列腺2例,左肾1例,胰腺1例,肝脏1例。14例EES均表现为单发实性肿块,13例呈团块状,病灶最大径线48.0~180.0 mm。8例密度或信号不均匀,8例可见囊变坏死,1例钙化。增强后8例呈不均匀强化,12例呈重度或中重度强化。10例形态不规则,11例有周围器官或组织侵犯,3例无周围器官和组织结构侵犯,5例合并周围骨质破坏,1例合并左肾静脉和下腔静脉癌栓和血栓、髂静脉血栓。结论 EES临床症状无特异性,影像上多表现为骨外软组织内体积巨大的实性肿块,密度或信号多不均匀,形态不规则,常伴囊变、坏死并侵犯周围器官或组织,影像学对术前诊断、临床分期、治疗及疗效评估具有重要价值。

关键词：尤因肉瘤磁共振成像体层摄影术 X线计算机病理学

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ICU护士道德困境心理体验质性研究的Meta整合

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中华护理杂志 2024年第10期59卷 1263-1269页

作者：赵宝生王娟王曼丽史俊杰杜军李凤霞山东第一医科大学附属省立医院急救中心济南市250021 山东第一医科大学附属省立医院心外监护室济南市250021

目的系统评价ICU护士道德困境的心理感受和真实经历,旨在为制订针对性的心理干预方案提供参考。方法计算机检索PubMed、CINAHL、Embase、Web of Science、Cochrane Library、PsycNET、中国知网、万方数据库、维普数据库、中国生物医学... 详细信息

目的系统评价ICU护士道德困境的心理感受和真实经历,旨在为制订针对性的心理干预方案提供参考。方法计算机检索PubMed、CINAHL、Embase、Web of Science、Cochrane Library、PsycNET、中国知网、万方数据库、维普数据库、中国生物医学文献数据库等中英文数据库,筛选有关ICU护士道德困境的心理感受和真实经历的质性研究,检索时限为建库至2023年3月。采用澳大利亚乔安娜布里格斯研究所循证卫生保健中心制订的质性研究质量评价标准(2016版)进行文献质量评价,采用汇集性整合方法对结果进行分析、整合。结果共纳入10篇文献,包括3篇现象学研究、7篇描述性质性研究。提炼出27个研究结果,归纳成8个新类别,综合成3个整合结果:①道德困境的内外缘由,包括生死观念矛盾、优逝理念参差、临床决策冲突、组织支持不足;②道德困境的渐进影响,包括加重消极情绪负担、滋生职业认同偏倚;③道德困境的应对策略,包括积极自我调试、寻求多元支持。结论亟需普及患者及家属科学生死观,深化优逝理念,缓和医护患决策冲突;关注ICU护士负性的情绪状态,提高其职业认同感;改善ICU护士自我调适途径,给予多元组织支持。

关键词：重症监护病房护士道德困境质性研究 Meta整合循证护理学护理管理研究

An analytical biomarker for treatment of patients with recurrent B-ALL after remission induced by infusion of anti-CD19 chimeric antigen receptor T(CAR-T) cells

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Science China(Life Sciences) 2016年第4期59卷 379-385页

作者： Yajing Zhang Wenying Zhang Hanren Dai Yao Wang fengxia shi Chunmeng Wang Yelei Guo Yang Liu Meixia Chen Kaichao Feng Yan Zhang Chuanjie Liu Qingming Yang Suxia Li Weidong Han Bio-therapeutic Department Chinese PLA General Hospital Molecular & Immunological Department Institute of Basic Medicine School of Life Sciences Chinese PLA General Hospital Department of Geriatric Hematology Chinese PLA General Hospital State key laboratory of kidney disease Chinese PLA General Hospital

Anti-CD19 chimeric antigen receptor-modified T(CAR-T-19) cells have emerged as a powerful targeted immunotherapy for B-cell lineage acute lymphoblastic leukemia with a remarkable clinical response in recent trials. Nonetheless, few data are available on the subsequent clinical monitoring and treatment of the patients, especially those with disease recurrence after CAR-T-19 cell infusion. Here, we analyzed three patients who survived after our phase I clinical trial and who were studied by means of biomarkers reflecting persistence of CAR-T-19 cells in vivo and predictive factors directing further treatment. One patient achieved 9-week sustained complete remission and subsequently received an allogeneic hematopoietic stem cell transplant. Another patient who showed relapse after 20 weeks without detectable leukemia in the cerebrospinal fluid after CAR-T-19 cell treatment was able to achieve a morphological remission under the influence of stand-alone low-dose chemotherapeutic agents. The third patient gradually developed extensive extramedullary involvement in tissues with scarce immune-cell infiltration during a long period of hematopoietic remission after CAR-T-19 cell therapy. Long-term and discontinuous increases in serum cytokines(mainly interleukin 6 and C-reactive protein) were identified in two patients(Nos. 1 and 6) even though only a low copy number of CAR molecules could be detected in their peripheral blood. This finding was suggestive of persistent functional activity of CAR-T-19 cells. Combined analyses of laboratory biomarkers with their clinical manifestations before and after salvage treatment showed that the persistent immunosurveillance mediated by CAR-T-19 cells would inevitably potentiate the leukemia-killing effectiveness of subsequent chemotherapy in patients who showed relapse after CAR-T-19-induced remission.

关键词：生物标志物免疫治疗 CD19 T细胞异基因造血干细胞移植患者复发受体

Identification of key genes affecting porcine fat deposition based on coexpression network analysis of weighted genes

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Journal of Animal Science and Biotechnology 2022年第1期13卷 36-51页

作者： Kai Xing Huatao Liu fengxia Zhang Yibing Liu Yong shi Xiangdong Ding Chuduan Wang Animal Science and Technology College Beijing University of AgricultureBeijingChina Key Laboratory of Animal Genetics Breeding and ReproductionMinistry of AgricultureNational Engineering Laboratory for Animal BreedingCollege of Animal Science and TechnologyChina Agricultural UniversityBeijingChina

Background:Fat deposition is an important economic consideration in pig production.The amount of fat deposition in pigs seriously affects production efficiency,quality,and reproductive performance,while also affecting consumers’choice of pork.Weighted gene co-expression network analysis(WGCNA)is effective in pig genetic studies.Therefore,this study aimed to identify modules that co-express genes associated with fat deposition in pigs(Songliao black and Landrace breeds)with extreme levels of backfat(high and low)and to identify the core genes in each of these modules.Results:We used RNA sequences generated in different pig tissues to construct a gene expression matrix consisting of 12,862 genes from 36 samples.Eleven co-expression modules were identified using WGCNA and the number of genes in these modules ranged from 39 to 3,363.Four co-expression modules were significantly correlated with backfat thickness.A total of 16 genes(RAD9A,IGF2R,SCAP,TCAP,SMYD1,PFKM,DGAT1,GPS2,IGF1,MAPK8,FABP,FABP5,LEPR,UCP3,APOF,and FASN)were associated with fat deposition.Conclusions:RAD9A,TCAP,SMYD1,PFKM,GPS2,and APOF were the key genes in the four modules based on the degree of gene connectivity.Combining these results with those from differential gene analysis,SMYD1 and PFKM were proposed as strong candidate genes for body size traits.This study explored the key genes that regulate porcine fat deposition and lays the foundation for further research into the molecular regulatory mechanisms underlying porcine fat deposition.

关键词： Fat deposition Pigs RNA-seq WGCNA

基于双层反对称阻尼式声子晶体的双通路宽频带噪声抑制方法研究

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振动与冲击 2024年第11期43卷 155-164页

作者：白晓天肖照洋石怀涛罗忠赵金宝何凤霞沈阳建筑大学机械工程学院沈阳110168 东北大学航空动力装备振动及控制教育部重点实验室沈阳110819

针对现有声子晶体模型难以在结构传播与空气传播双通路实现噪声抑制的问题,提出了一种双层反对称阻尼式声子晶体结构,以双层阻尼式声子晶体为单元抑制噪声结构传播,将迷宫型散射体反对称式排列抑制噪声空气传播,实现双通路宽频带降噪。... 详细信息

针对现有声子晶体模型难以在结构传播与空气传播双通路实现噪声抑制的问题,提出了一种双层反对称阻尼式声子晶体结构,以双层阻尼式声子晶体为单元抑制噪声结构传播,将迷宫型散射体反对称式排列抑制噪声空气传播,实现双通路宽频带降噪。研究基于有限元理论与力声类比法对模型的能带图、传递曲线与吸声系数进行计算,对比分析了吸声性能与传统结构的差异,并通过试验进行验证。研究发现,模型中的双层阻尼—散射体结构可将降噪带宽拓展为传统结构的3.3倍,且同体积附加质量仅为传统结构的53.3%,反对称结构可突破吸声系数瓶颈,实现高效吸声。结果表明该模型可以实现双通道宽频带范围内的噪声控制,并具有轻质化的特点,能很好地补足现有声子晶体模型在宽频带噪声控制领域的短板。

关键词：声子晶体双通路降噪宽频带降噪噪声抑制