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Double-layered osmotic pump controlled release tablets of actarit: In vitro and in vivo evaluation 被引量:9
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作者 Yuenan Li Hao Pan +6 位作者 Hongliang Duan Jianting Chen Zhihong Zhu Jingxin Fan Pingfei Li Xinggang Yang Weisan Pan 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第3期340-348,共9页
The aim of the study was to develop actarit double-layered osmotic pump tablets to overcome the weak points of actarit common tablets, such as short half-life and large plasma concentration fluctuations. Single factor... The aim of the study was to develop actarit double-layered osmotic pump tablets to overcome the weak points of actarit common tablets, such as short half-life and large plasma concentration fluctuations. Single factor experiment and orthogonal test were applied to optimize the formulation;the pharmacokinetic study was performed in beagle dogs adopting actarit common tablets as reference tablets. The optimal formulation was as follows: drug layer: 150 mg actarit, 240 mg PEO-N80, 50 mg NaCl;push layer: 140 mg PEO-WSR303, 20 mg NaCl;coating solution: 30 g cellulose acetate and 6 g PEG 4000 in 1000 ml 94% acetone solution, 60 mg coating weight gain. The pharmacokinetic study showed that T max was prolonged by the contrast of commercial common tablets with constant drug release rate, but the bioavailability was equivalent. And a good in vivo –in vitro correlation of the actarit osmotic pump tablets was also established. The designed actarit osmotic pump tablets can be applied for rheumatoid arthritis, proposing a promising replacement for the marked common products. 展开更多
关键词 Actarit double-layered OSMOTIC pump TABLET PHARMACOKINETICS In vivo –in VITRO correlation
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Extracorporeal membrane oxygenation combined with intra-aortic balloon counterpulsation for pheochromocytoma:A case report
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作者 Shu-Ying Zeng Hai-Hui Wu +1 位作者 Zhi-Hong Yu Qing-Qian Zhang 《World Journal of Clinical Cases》 2025年第15期42-49,共8页
BACKGROUND Pheochromocytoma(PHEO)is a type of tumor that originates from chromaffin cells in the adrenal medulla and is classified as an adrenal paraganglioma.PHEOs can secrete catecholamines,leading to a variety of s... BACKGROUND Pheochromocytoma(PHEO)is a type of tumor that originates from chromaffin cells in the adrenal medulla and is classified as an adrenal paraganglioma.PHEOs can secrete catecholamines,leading to a variety of symptoms.Accurate diagnosis and appropriate treatment selection are crucial for favorable outcomes in these cases.CASE SUMMARY The patient presented with unexplained chest tightness,palpitations,and pink sputum.Upon examination and analysis of laboratory results,a diagnosis of adrenal PHEO was established.The PHEO secreted high levels of catecholamines,causing sudden fluctuations in blood pressure and heart rate,leading to extre-mely unstable hemodynamics.Treatment with extracorporeal membrane oxygenation and intra-aortic balloon counterpulsation helped stabilize the patient’s vital signs,allowing for timely surgical intervention.CONCLUSION The combination of extracorporeal membrane oxygenation and intra-aortic balloon counterpulsation can enhance tissue perfusion,thus providing a solid foundation for the accurate diagnosis and effective surgical treatment of PHEO. 展开更多
关键词 PHEOCHROMOCYTOMA Pheochromocytoma crisis Extracorporeal membrane oxygenation Intra-aortic balloon pump Case report
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Early plasmapheresis in type 2 benign recurrent intrahepatic cholestasis:A case report and review of literature
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作者 Lander Heyerick Annemieke Dhondt +3 位作者 Hans Van Vlierberghe Xavier Verhelst Sarah Raevens Anja Geerts 《World Journal of Hepatology》 2025年第2期279-285,共7页
BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive liver disease,causing episodic cholestasis with intense pruritus.This case report highlights the effectiveness of early plasmaphe... BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive liver disease,causing episodic cholestasis with intense pruritus.This case report highlights the effectiveness of early plasmapheresis as a therapeutic option for BRIC type 2,offering rapid symptom relief and early termination of cholestatic episodes.It contributes to the limited evidence supporting plasmapheresis as a treatment for BRIC flares resistant to conventional therapies.CASE SUMMARY A 43-year-old male with BRIC type 2 presented with fatigue,jaundice,and severe pruritus,triggered by a recent mild severe acute respiratory syndrome coronavirus 2 infection.Laboratory results confirmed cholestasis with elevated bilirubin and alkaline phosphatase.First-line pharmacological treatments,including cholestyramine and rifampicin,failed.Endoscopic nasobiliary drainage was ineffective,prompting initiation of plasmapheresis.This intervention rapidly relieved pruritus,with complete biochemical normalisation after 11 sessions.Two years later,a similar episode occurred,and early reinitiation of plasmapheresis led to symptom resolution within two sessions and biochemical recovery within two weeks.The patient tolerated the procedure well,with no adverse effects observed.Follow-up showed no signs of cholestasis recurrence.CONCLUSION Plasmapheresis is a safe and effective option for therapy-refractory BRIC type 2,particularly when initiated early in cholestasis. 展开更多
关键词 CHOLESTASIS Benign recurrent intrahepatic 2 PLASMAPHERESIS PRURITUS CHOLESTASIS Bile salt export pump Case report
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PREDICTION OF PUMP CHARACTERISTICS ACCORDING TO GEOMETRICAL PARAMETERS OF IMPELLER AND VOLUTE CASING
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作者 Wei Guangxin Guan Xingfan +1 位作者 Guo Nailong Huang Daojian(Jiangsu University of Science and Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第4期272-277,共17页
The geometrical parameters of impeller or volute casing (including guide vane ofmultistage pump) have a great effect on pump characteristics, but ultimately. the pump characteris-tics are determined by the geometrical... The geometrical parameters of impeller or volute casing (including guide vane ofmultistage pump) have a great effect on pump characteristics, but ultimately. the pump characteris-tics are determined by the geometrical parameters of impeller and volute casing cooperatively. Inthis essay the effect of impeller and volute casing on pump characteristics will be studiedquantitatvely from the angle cf optimal matching of them. 展开更多
关键词 pump characteristics Impeller Volute casing Geometrical parameter Predic-tion
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Horizontal aquifer movement induced by groundwater pumping and its applications to the analysis of some geological disasters 被引量:1
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作者 王庆良 王文萍 +1 位作者 梁伟锋 刘练 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第4期106-114,共9页
Based on Darcy Gersevanov law concerning a flow relation between water and solids, we derive the horizontal movement of solid frame resulted from a discharging well in a Theis Thiem confined system, and further anal... Based on Darcy Gersevanov law concerning a flow relation between water and solids, we derive the horizontal movement of solid frame resulted from a discharging well in a Theis Thiem confined system, and further analyze the relations among the horizontal movements and pumped time t as well as radius r from the discharging well. As applications of the theory, we propose some new interperations for ground fissure activity and casing failures induced by groundwater withdrawal or injection. 展开更多
关键词 pumpING AQUIFER horizontal movement ground fissure casing failure
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Performances and Rotating Flows of Rotary Jet Pump 被引量:1
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作者 Keiichi Komaki Toshiaki Kanemoto Kenji Sagara 《Open Journal of Fluid Dynamics》 2012年第4期375-379,共5页
The rotary jet pumps, namely the pitot pumps, are composed of the rotating casing with the impeller channels and the stationary pick-up tube for discharging, are known as the one of high pressure pumps in the U.S. mar... The rotary jet pumps, namely the pitot pumps, are composed of the rotating casing with the impeller channels and the stationary pick-up tube for discharging, are known as the one of high pressure pumps in the U.S. market. The pumps, however, have been prepared experientially, because of poor knowledge for the flow conditions and the pump performances. Then, this paper discusses the pump performances and the internal flow conditions in the rotating casing. Three types of the pick-up tube were prepared for the experiments to know the pump performances and the flow conditions in the rotating casing. The flow in the rotating casing is nearly in the forced vortex type and gives the higher pressure at the pick-up tube inlet. The more cross-sectional area of the pick-up tube channel is large, the more head and discharge are higher with excellent efficiency. Moreover, the authors confirmed that the secondary flow runs toward the rotating center at the wake flow region behind the pick-up tube. 展开更多
关键词 Rotation casing Type pump Pitot pump High Pressure pump PICK-UP Tube FORCED Vortex Secondary Flow
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Progressive familial intrahepatic cholestasis—farnesoid X receptor deficiency due to NR1H4 mutation:A case report 被引量:1
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作者 Piotr Czubkowski Richard J Thompson +7 位作者 Irena Jankowska A S Knisely Milton Finegold Pamela Parsons Joanna Cielecka-Kuszyk Sandra Strautnieks Joanna Pawłowska Laura N Bull 《World Journal of Clinical Cases》 SCIE 2021年第15期3631-3636,共6页
BACKGROUND Functioning farnesoid X receptor(FXR;encoded by NR1H4)is key to normal bile acid homeostasis.Biallelic mutations in NR1H4 are reported in a few children with intrahepatic cholestasis.We describe a boy with ... BACKGROUND Functioning farnesoid X receptor(FXR;encoded by NR1H4)is key to normal bile acid homeostasis.Biallelic mutations in NR1H4 are reported in a few children with intrahepatic cholestasis.We describe a boy with progressive familial intrahepatic cholestasis and homozygous mutation in NR1H4.CASE SUMMARY A boy had severe neonatal cholestasis with moderate hypercholanemia and persistently elevated alpha-fetoprotein.Despite medical treatment,coagulopathy was uncontrollable,prompting liver transplantation at age 8 mo with incidental splenectomy.The patient experienced catch-up growth with good liver function and did not develop allograft steatosis.However,1 year after transplant,he died from an acute infection,considered secondary to immunosuppression and asplenia.A homozygous protein-truncating mutation,c.547C>T,p.(Arg183Ter),was subsequently identified in NR1H4,and both parents were shown to be heterozygous carriers.Absence of FXR and of bile salt export pump expression was confirmed by immunostaining of explanted liver.CONCLUSION Severe cholestasis with persistently high alpha-fetoprotein and modest elevation of serum bile acid levels may suggest FXR deficiency.Some patients with FXR deficiency may not develop allograft steatosis and may respond well to liver transplantation. 展开更多
关键词 Neonatal cholestasis Progressive familial intrahepatic cholestasis Bile salt export pump Liver transplantation ALPHA-FETOPROTEIN Case report
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Twin reversed arterial perfusion sequence-a rare and dangerous complication form of monochorionic twins:A case report
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作者 Nguyen Duy Anh Nguyen-Thi Thu Ha +3 位作者 Nguyen-Thi Sim Nguyen Khac Toan Phan-Thi Huyen Thuong Nguyen Minh Duc 《World Journal of Clinical Cases》 SCIE 2022年第28期10214-10219,共6页
BACKGROUND Twin reversed arterial perfusion(TRAP) sequence is an extremely rare congenital anomaly in monochorionic(MC) twins.The condition is characterized by a malformed fetus(acardiac twin) without cardiac activiti... BACKGROUND Twin reversed arterial perfusion(TRAP) sequence is an extremely rare congenital anomaly in monochorionic(MC) twins.The condition is characterized by a malformed fetus(acardiac twin) without cardiac activities being perfused by a structurally normal one(pump twin) via an artery-to-artery anastomosis in a reverse direction.CASE SUMMARY We described the first case of TRAP to receive laser surgery in Vietnam.The 26-wk pregnancy was originally misdiagnosed in another hospital as MC twins with single intrauterine fetal death.Following admission to our center,the diagnosis was amended to a 26-wk TRAP sequence stage IIb.The acardiac twin was 7.5 cm at the longest length,the ratio of the weight of the acardiac twin to the weight of the pump twin was more than 90%,the pump twin showed fetal distress with absent diastolic flow in umbilical artery of pump twin,and the peak systolic velocity in the middle cerebral artery = 1.6 Mo M.We performed emergency laser photocoagulation of the acardiac twin’s umbilical cord.After surgery,we successfully maintained the pregnancy for 8 wk and ended it electively by cesarean section at 34 wk of gestation due to rupture of membranes.CONCLUSION TRAP should be appropriately diagnosed and treated early to avoid complications of the pump twin.Fetoscopic laser photocoagulation is a new and effective treatment for this condition. 展开更多
关键词 Twin reversed arterial perfusion Acardiac twin pump twin Laser Case report
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Nivolumab-induced tumour-like gastritis:A case report
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作者 Elena Cijauskaite Edita Kazenaite +2 位作者 Sandra Strainiene Goda Sadauskaite Benediktas Kurlinkus 《World Journal of Clinical Cases》 SCIE 2023年第18期4350-4359,共10页
BACKGROUND Immune checkpoint inhibitors are one of the modern treatment methods for advanced malignancies.However,this group of medications is also associated with various immune-related adverse events,such as colitis... BACKGROUND Immune checkpoint inhibitors are one of the modern treatment methods for advanced malignancies.However,this group of medications is also associated with various immune-related adverse events,such as colitis or pneumonitis.Immune checkpoint inhibitor-induced gastritis is a less common adverse event.CASE SUMMARY We describe a 64-year-old woman presenting with diarrhea,nausea,and discomfort in the upper abdominal region.The patient had a history of metastatic lung cancer,which was treated with nivolumab.During the first endoscopy,an infiltrating gastric tumour was suspected.Later,based on endoscopic,histological and radiological findings,nivolumab-induced gastritis was diagnosed.The patient was successfully treated with three courses of omeprazole.CONCLUSION As a consequence of the increased use of immune checkpoint inhibitors,a growing number of reported immune-related adverse events could be expected.The diagnosis of immune checkpoint inhibitor-induced gastritis should be considered when assessing a patient treated with nivolumab with upper gastrointestinal distress. 展开更多
关键词 Nivolumab Immune checkpoint inhibitors Tumour-like gastritis Proton pump inhibitors Case report
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22例质子泵抑制剂致严重皮肤不良反应的文献病例分析
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作者 尤晓明 朱星宇 +2 位作者 李芸 朱建国 谢诚 《中国药学杂志》 北大核心 2025年第8期875-882,共8页
目的探讨质子泵抑制剂(proton pump inhibitors,PPIs)致严重皮肤不良反应(severe cutaneous adverse reactions,SCARs)的发生特点,为临床安全用药提供参考。方法检索截至2024年6月收录在Pubmed、中国知网、万方和维普期刊数据库中PPIs致... 目的探讨质子泵抑制剂(proton pump inhibitors,PPIs)致严重皮肤不良反应(severe cutaneous adverse reactions,SCARs)的发生特点,为临床安全用药提供参考。方法检索截至2024年6月收录在Pubmed、中国知网、万方和维普期刊数据库中PPIs致SCARs的病例报道,采集患者的人口学特征、药物使用情况、SCARs的发生时间、类型、临床表现、处置措施及转归等信息,并进行描述性统计分析。结果共纳入22例患者,其中男性8例(36.4%),女性14例(63.6%),年龄23~89岁。涉及的PPIs包括奥美拉唑10例、埃索美拉唑6例、泮托拉唑3例和兰索拉唑3例。SCARs的发生时间为用药后1~45 d,其中18例(94.7%)发生于用药后3周内。10例诊断为史蒂文斯-约翰逊综合征(Stevens-Johnson syndrome,SJS)/中毒性表皮坏死松解症(toxic epidermal necrolysis,TEN),7例诊断为伴嗜酸性粒细胞增多和系统症状的药物反应(drug reaction with eosinophilia and systemic symptoms,DRESS),5例为急性泛发性发疹性脓疱病(acute generalized exanthematous pustulosis,AGEP)。18例(81.8%)患者经停药、糖皮质激素和/或球蛋白等治疗后临床症状和实验室检查指标均好转,但有3例患者最终死于多器官功能衰竭,1例患者自动出院。结论多种PPIs可导致SCARs,以奥美拉唑和埃索美拉唑相对较多,且主要表现为SJS/TEN和DRESS。在使用PPIs的6周内应密切关注患者有无发热、皮疹等过敏症状,一旦怀疑可能为SCARs应及时停药,必要时予以糖皮质激素等药物对症支持治疗。 展开更多
关键词 质子泵抑制剂 严重皮肤不良反应 文献病例分析 药品不良反应
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某型航空燃油齿轮泵流固耦合分析与试验研究
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作者 王建森 田世荣 +1 位作者 司国雷 陈君辉 《机床与液压》 北大核心 2025年第1期124-131,共8页
针对理论计算难以获得外啮合齿轮泵齿轮副变形对泵壳扫膛的问题,利用PumpLinx和ABAQUS进行联合仿真,建立燃油齿轮泵单向流固耦合模型。计算燃油泵齿轮所受径向力及随齿轮转角的变化规律,得到齿轮副在压力载荷和啮合力作用下的力学特性变... 针对理论计算难以获得外啮合齿轮泵齿轮副变形对泵壳扫膛的问题,利用PumpLinx和ABAQUS进行联合仿真,建立燃油齿轮泵单向流固耦合模型。计算燃油泵齿轮所受径向力及随齿轮转角的变化规律,得到齿轮副在压力载荷和啮合力作用下的力学特性变化,并研究流固耦合作用对齿轮副的变形分布影响。结果表明:流场仿真以及泵壳内壁扫膛的方位与主、从动齿轮所受径向力的方位一致性良好;流固耦合作用对齿轮结构产生较大影响,最大变形均发生在齿轮齿顶中间位置,且计算所得最大扫膛深度与实测平均值大致相同,验证了该模型及计算方法的有效性。 展开更多
关键词 齿轮泵 径向力 流固耦合 齿轮变形 泵壳扫膛
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高强耐热铸造铝合金及其航空发动机复杂壳体铸件的性能研究
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作者 茄菊红 谢峰 +6 位作者 冯超 王平海 余腾飞 杨朝阳 郗洪雷 肖文龙 马朝利 《材料工程》 北大核心 2025年第1期186-194,共9页
针对先进航空发动机对高强耐热铝合金复杂壳体铸件的应用需求,对比分析一种新型Al-Si-Cu-Mg-Sc高强耐热铝合金与ZL101A,ZL205A铸造铝合金的工艺性能及力学性能,并采用高强耐热铝合金开展油泵复杂壳体金属型铸造工艺设计和实验验证,对铸... 针对先进航空发动机对高强耐热铝合金复杂壳体铸件的应用需求,对比分析一种新型Al-Si-Cu-Mg-Sc高强耐热铝合金与ZL101A,ZL205A铸造铝合金的工艺性能及力学性能,并采用高强耐热铝合金开展油泵复杂壳体金属型铸造工艺设计和实验验证,对铸件产品的质量进行检测分析。结果表明:新型Al-Si-Cu-Mg-Sc高强耐热铝合金的铸造流动性和抗热裂性能优于ZL205A高强铸造铝合金,其金属型铸造油泵复杂壳体的合格率与ZL101A同类壳体相当。新型合金的单铸试样和铸件本体取样的室温平均抗拉强度均达到420 MPa以上,明显高于ZL101A合金,250℃时其抗拉强度优于ZL205A合金。铸件的表面质量、内部质量、气密性和承压性能均满足产品设计要求。 展开更多
关键词 高强耐热铝合金 Al-Si-Cu-Mg 铸造性能 力学性能 航空发动机油泵壳体
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周向槽机匣处理对轴流泵空化特性的影响
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作者 童志庭 路祥宾 +2 位作者 苏宏冉 张功元 张月 《流体机械》 北大核心 2025年第10期111-118,共8页
为了抑制低扬程潜水轴流泵运行过程中的空化问题,将压气机周向槽机匣处理扩稳方法,拓展应用于轴流泵,设计了7种机匣处理的方案,基于SST k-ε湍流模型和Zwart-Gerber-Belamri空化模型,通过定常数值模拟,分别从周向槽的安装位置、槽宽和槽... 为了抑制低扬程潜水轴流泵运行过程中的空化问题,将压气机周向槽机匣处理扩稳方法,拓展应用于轴流泵,设计了7种机匣处理的方案,基于SST k-ε湍流模型和Zwart-Gerber-Belamri空化模型,通过定常数值模拟,分别从周向槽的安装位置、槽宽和槽深3个方面,研究对轴流泵空化性能的影响。结果表明,空化现象是由叶顶泄漏流逸出形成的低气压区域造成;安装周向槽后,轴流泵扬程存在一定损失,安装位置对轴流泵空化影响最大;相较光壁机匣,周向槽位于轴向弦长10%位置时空化提前发生,位于叶顶轴向弦长前缘45%位置时抗空化性能最好,必需汽蚀余量降低2.9%;3组不同宽度的周向槽对比发现,随着周向槽宽度的增加,泵的抗空化性能越好,必需汽蚀余量最高降低4.01%,但扬程损失也在增加;3种不同高度的周向槽均使必需汽蚀余量降低了2.9%,表明周向槽高度对空化性能的影响较小。研究结果可为水泵空化现象的抑制提供理论依据。 展开更多
关键词 轴流泵 机匣处理 数值模拟 叶顶泄漏流 空化性能
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采空区地下水库容量分析及抽水蓄能实例研究
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作者 廖庆龙 杨帆 +2 位作者 李永福 姜德义 王谦 《地下空间与工程学报》 北大核心 2025年第2期709-719,共11页
为了实现“双碳”战略,国家正逐步采取措施降低燃煤火电比重,增加清洁能源太阳能和风能等的使用。近些年由于可再生能源的时空不确定性和大型储能设施的匮乏,弃风弃电弃光现象愈演愈烈。为了提高风能和太阳能的利用率,提出在太阳能风能... 为了实现“双碳”战略,国家正逐步采取措施降低燃煤火电比重,增加清洁能源太阳能和风能等的使用。近些年由于可再生能源的时空不确定性和大型储能设施的匮乏,弃风弃电弃光现象愈演愈烈。为了提高风能和太阳能的利用率,提出在太阳能风能富集地区利用废弃煤矿采空区作为地下抽水蓄能水库,以促进可再生能源的转储并用。论文从采空区最大库容、可用库容和气液交换等方面分析了采空区作为抽水蓄能地下水库的储存能力,并结合我国典型废弃煤矿采空区特点和相关气象数据,分析了拟建采空区地下水库的储能系统的能量和库容变化特征。综合分析得出结论:在风能和太阳能丰富的中国西北和西南地区,利用废弃煤矿采空区开发抽水蓄能电厂在技术上是可行的。 展开更多
关键词 抽水蓄能 清洁能源 煤矿采空区 可行性分析 案例分析
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毕节王丰天然矿泉水资源勘查井钻探施工技术
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作者 邵颂友 赵华宣 +3 位作者 陈涛 陈浩 贾玉川 胡暑月 《地下水》 2025年第3期133-137,共5页
毕节王丰饮用天然矿泉水资源勘查井区实施过程中存在地层含铁质或炭质有害物质、同含水层的邻井相互干扰以及水源地部分区域村寨聚集等矿泉水勘探开采难题。钻探施工通过采用“大径预留、小径勘探”的井身设计、双层套管加深固结封隔、... 毕节王丰饮用天然矿泉水资源勘查井区实施过程中存在地层含铁质或炭质有害物质、同含水层的邻井相互干扰以及水源地部分区域村寨聚集等矿泉水勘探开采难题。钻探施工通过采用“大径预留、小径勘探”的井身设计、双层套管加深固结封隔、空气潜孔锤钻进等措施,应用群孔干扰抽水与开采抽水结合的开采量计算法,依据涌水量及环境条件等因素评价成井类别,提高了勘查成井质量,确保了探获优质矿泉水资源,为类似矿泉水资源勘查开发提供了借鉴和参考。 展开更多
关键词 矿泉水资源勘查井 双层套管 空气潜孔锤 群孔干扰抽水 成井类别评价
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抽水蓄能电站抽水开机过程中充水保压蜗壳非线性接触流激响应研究
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作者 卢兆辉 张绍政 +3 位作者 任庆丰 罗雨桐 杨楚楠 王正伟 《大电机技术》 2025年第1期99-109,共11页
为了研究保压值对充水保压蜗壳在机组运行期的影响,本文针对一台原型水泵水轮机组的保压蜗壳-混凝土结构进行了流固耦合分析。利用RANS方法结合SST k-ω湍流模型,对机组抽水开机过程中的流场进行了数值计算,并以流场压力为边界条件,进... 为了研究保压值对充水保压蜗壳在机组运行期的影响,本文针对一台原型水泵水轮机组的保压蜗壳-混凝土结构进行了流固耦合分析。利用RANS方法结合SST k-ω湍流模型,对机组抽水开机过程中的流场进行了数值计算,并以流场压力为边界条件,进行了蜗壳与厂房混凝土结构场的有限元计算。分析了蜗壳内的压力场、速度场变化规律,并比较了不同保压值下蜗壳与混凝土的应力应变分布情况及接触状态。结果表明:机组蜗壳中的压力变化主要受导叶打开规律影响,整个开机过程中蜗壳内的流动易出现漩涡,受导叶开度与周向不均匀流动的综合因素影响。蜗壳在不同保压取值下变形及应力变化趋势基本一致,位移主要是受初始保压间隙的影响,而应力变化则主要受内部压力波动的影响。混凝土提前接触会导致开裂风险区域随保压值的增大而增加。在本研究工况中,最小保压值3.2MPa对于降低混凝土的开裂风险更有利,说明在实际工程中增大保压值并不能总是保证混凝土结构更安全。 展开更多
关键词 抽水蓄能电站 蜗壳 充水保压蜗壳 接触 流固耦合
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大型立式轴流泵故障分析与防治措施研究
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作者 聂朋 宗志华 苏培凡 《山西水利科技》 2025年第4期38-41,共4页
针对大型立式轴流泵机组在长期高负荷运行中频繁出现的导轴承损坏、叶片调节机构失效、电机故障及振动问题,研究其故障机理并提出系统性防治措施。通过案例分析、结构分析与监测技术相结合,对导轴承润滑密封失效、叶片调节机构卡阻、电... 针对大型立式轴流泵机组在长期高负荷运行中频繁出现的导轴承损坏、叶片调节机构失效、电机故障及振动问题,研究其故障机理并提出系统性防治措施。通过案例分析、结构分析与监测技术相结合,对导轴承润滑密封失效、叶片调节机构卡阻、电机推力瓦烧损及机组振动等故障进行机理研究,提出材料优化、润滑管理、结构改进和智能监控等综合防治方法,并基于实际工程数据验证措施的有效性。研究发现,导轴承故障主要由水封失效或润滑污染引发,采用耐磨材料与实时监控技术可降低50%以上故障率;叶片调节机构通过内置液压系统与密封优化可减少30%的卡阻风险;振动控制中,水位调节与叶片角度优化可使振动位移降低40%,推力瓦材料升级和冷却系统改进则显著降低电机过热概率。 展开更多
关键词 立式轴流泵 故障分析 案例 防治
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基于三种多指标评价方法的注塑工艺参数优化
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作者 化君益 范希营 +3 位作者 郭永环 张鑫然 丁文杰 王志江 《塑料》 北大核心 2025年第2期152-159,共8页
真空泵壳的作用是将叶轮封闭在一定的空间,以便叶轮吸入和压出液体。对于真空泵后壳而言,体积收缩较大且存在翘曲变形,影响泵壳的封闭性。结合该问题,以翘曲变形量与体积收缩率为优化指标。设计7因素5水平正交试验,通过极差和方差分析,... 真空泵壳的作用是将叶轮封闭在一定的空间,以便叶轮吸入和压出液体。对于真空泵后壳而言,体积收缩较大且存在翘曲变形,影响泵壳的封闭性。结合该问题,以翘曲变形量与体积收缩率为优化指标。设计7因素5水平正交试验,通过极差和方差分析,初步得到单指标最优工艺参数组合。极差分析的优方案仅针对单指标,因此,引入3种不同的多指标综合评价方法,将灰色关联评价、熵权-TOPSIS、CRITIC-TOPSIS 3种评分方法的优方案进行对比。最后,得出最佳多目标评分方法为CRITIC-TOPSIS及对应的最优工艺参数组合。优化后,塑件的翘曲变形量为0.8664 mm,体积收缩率为8.233%,与初始值相比,降低了46.78%和21.29%。 展开更多
关键词 真空泵后壳 注塑成型 工艺参数优化 正交试验设计 多指标评价模型
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主泵泵壳水压试验应变测试
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作者 黄进 《一重技术》 2025年第4期51-53,共3页
介绍核岛主泵泵壳水压试验的应变测试方法,通过两次循环水压试验采集内壁7个测点与外壁3个测点的应变数据,结合广义胡克定律计算应力值,分析材料在高压下的弹塑性行为及强度贮备能力。结果表明,测试系统稳定可靠,泵壳通过水压试验可以... 介绍核岛主泵泵壳水压试验的应变测试方法,通过两次循环水压试验采集内壁7个测点与外壁3个测点的应变数据,结合广义胡克定律计算应力值,分析材料在高压下的弹塑性行为及强度贮备能力。结果表明,测试系统稳定可靠,泵壳通过水压试验可以实现强度贮存,降低工作应力水平,提升运行安全性。 展开更多
关键词 主泵泵壳 水压试验 应变测试
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钛合金离心泵壳机加工石墨型铸造工艺研究
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作者 马建杰 《山西冶金》 2025年第7期22-24,共3页
对钛合金离心泵壳的铸造与机加工工艺进行研究,旨在优化生产流程,提高产品质量。试验材料选择Ti-6Al-4V钛合金,并采用高温真空熔炼炉、石墨铸造模具、数控车铣复合机床和粗糙度测量仪等设备,以满足高精度加工的需求。选择适宜的切削速度... 对钛合金离心泵壳的铸造与机加工工艺进行研究,旨在优化生产流程,提高产品质量。试验材料选择Ti-6Al-4V钛合金,并采用高温真空熔炼炉、石墨铸造模具、数控车铣复合机床和粗糙度测量仪等设备,以满足高精度加工的需求。选择适宜的切削速度,并优化切削过程中的材料去除率,确保加工稳定性。试验结果表明:通过优化钛合金离心泵壳加工参数,不仅可以提高加工效率,缩短生产周期,而且为钛合金离心泵壳的生产提供了新的解决方案。 展开更多
关键词 钛合金 离心泵壳 机加工 石墨铸造
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