检索结果-南通市图书馆

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping Li Jin-ya Zhang Jia-Xiang Zhang Yong-Xue Zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

Acupuncture for obesity and related diseases:Insight for regulating neural circuit

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Medicine 2024年第2期22卷 93-101页

作者： Lin-yan Jiang Jun Tian ya-nan yang Shao-hui Jia qing Shu Department of Rehabilitation Medicine Zhongnan HospitalWuhan UniversityWuhan 430071Hubei ProvinceChina School of Sports Medicine Wuhan Sports UniversityWuhan 430079Hubei ProvinceChina Department of Traditional Chinese Medicine China Resources&Wu Gang General HospitalWuhan 430080Hubei ProvinceChina

Obesity is defined as abnormal or excessive fat accumulation that may impair *** is associated with numerous pathological changes including insulin resistance,fatty liver,hyperlipidemias,and other obesity-related *** comorbidities comprise a significant public health *** anti-obesity drugs have been limited by side effects that include depression,suicidal thoughts,cardiovascular complications and *** treatment has been shown to be effective for treating obesity and obesity-related conditions,while avoiding side ***,the mechanisms of acupuncture in treating obesity-related diseases,especially its effect on neural circuits,are not well understood.A growing body of research has studied acupuncture’s effects on the endocrine system and other mechanisms related to the regulation of neural *** this article,recent research that was relevant to the use of acupuncture to treat obesity and obesity-related diseases through the neuroendocrine system,as well as some neural circuits involved,was *** on this,acupuncture’s potential ability to regulate neural circuits and its mechanisms of action in the endocrine system were reviewed,leading to a deeper mechanistic understanding of acupuncture’s effects and providing insight and direction for future research about obesity.

关键词： Obesity Acupuncture Neural circuit Appetite Energy metabolism

Triggering triplet excitons of carbon nanodots through nanospace domain confinement for multicolor phosphorescence in aqueous solution

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6534-6543页

作者： ya-Chuan Liang qing Cao Yuan Deng Yong Wang Kai-Kai Liu Chong-Xin Shan School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002China Henan Key Laboratory of Diamond Optoelectronic Material and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China

Easy non-radiative decay property of long-lived triplet excitons in aqueous solution obstructs their applications in aquatic *** reported phosphorescence phenomena in aqueous solution have excited researchers enormously but achieving full-color water-soluble phosphorescent carbon nanodots(CNDs)is still a challenging ***,full-color phosphorescence of water-soluble CNDs has been demonstrated by triggering their triplet excitons through nanospace domain confinement,and Förster energy resonance transfer is used for further tuning phosphorescence *** phosphorescence spans across most of the visible spectrum,ranging from 400 to 700 *** an aqueous solution,the CNDs exhibits blue,green,and red phosphorescence,lasting for approximately 6,10,and 7 s,***,the phosphorescence quantum yields are 11.85%,8.6%and 3.56%,making them readily discernible to the naked eyes and laying a solid foundation for practical ***,phosphorescence flexible optical display and bioimaging have been demonstrated by using the multicolor CNDs-based nanomaterials,showing distinct superiority for accuracy and complete display and imaging in complex emission background.

关键词： carbon nanodots triplet excitons multicolor aqueous solution

Observation of thickness-tuned universality class in superconducting β-W thin films

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2021年第18期66卷 1830-1838,M0003页

作者： Ce Huang Enze Zhang Yong Zhang Jinglei Zhang Faxian Xiu Haiwen Liu Xiaoyi Xie Linfeng Ai Yunkun yang Minhao Zhao Junjie Qi Lun Li Shanshan Liu Zihan Li Runze Zhan ya-qing bie Xufeng Kou Shaozhi Deng X.C.Xie State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China School of Information Science and Technology ShanghaiTech UniversityShanghai 201210China Anhui Province Key Laboratory of Condensed Matter Physics at ExtremeConditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Shanghai Research Center for Quantum Sciences Shanghai 201315China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China

The interplay between quenched disorder and critical behavior in quantum phase transitions is conceptually fascinating and of fundamental importance for understanding phase transitions. However, it is still unclear whether or not the quenched disorder influences the universality class of quantum phase transitions. More crucially, the absence of superconducting-metal transitions under in-plane magnetic fields in 2D superconductors imposes constraints on the universality of quantum criticality. Here, we observe the thickness-tuned universality class of superconductor-metal transition by changing the disorder strength in b - W films with varying thickness. The finite-size scaling uncovers the switch of universality class: quantum Griffiths singularity to multiple quantum criticality at a critical thickness of tc⊥1~ 8 nm and then from multiple quantum criticality to single criticality at tc⊥2~ 16 nm. Moreover, the superconducting-metal transition is observed for the first time under in-plane magnetic fields and the universality class is changed at tc‖~ 8 nm. The observation of thickness-tuned universality class under both out-of-plane and in-plane magnetic fields provides broad information for the disorder effect on superconducting-metal transitions and quantum criticality.

关键词： Quenched disorder Quantum criticality Universality class quantum Griffiths singularity

Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-qing Zhang Kai-Ning Shi yao-yao Shi Yi-Hui Song Zhe He ya-Song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

Research progress in CALPHAD assisted metal additive manufacturing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2024年第4期21卷 295-310页

作者： ya-qing Hou Xiao-qun Li Wei-dong Cai qing Chen Wei-ce Gao Du-peng He Xue-hui Chen Hang Su China Iron&Steel Research Institute Group Beijing 100081China Thermo-Calc Software AB SolnaSE-169Sweden KTH Royal Institute of Technology StockholmSE-100Sweden Central Iron and Steel Research Institute Beijing 100081China

Metal additive manufacturing(MAM)technology has experienced rapid development in recent *** both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of *** calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple *** combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal *** development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural *** endeavor carries considerable theoretical and practical *** paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties ***,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions.

关键词： metal additive manufacturing CALPHAD integrated computational material engineering powder bed fusion material design microstructure simulation

Association between childhood obesity and gut microbiota:16S rRNA gene sequencing-based cohort study

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第16期30卷 2249-2257页

作者： Xu-Ming Li qing Lv ya-Jun Chen Lu-Biao yan Xin Xiong Laboratory Department Nanjing Medical University Affiliated Obstetrics and Gynecology Hospital(Nanjing Maternal and Child Health Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Shenzhen University General HospitalShenzhen 518055Guangdong ProvinceChina Department of Inspection Division Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Neonatology Chenzhou First People’s HospitalChenzhou 423000Hunan ProvinceChina

BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA *** research aimed to provide insights for mechanistic studies and prevention strategies for childhood *** normal-weight and thirty age-and sex-matched obese children were *** and body measurements were collected,and fecal samples underwent 16S rDNA *** differences in body mass index(BMI)and body-fat percentage were observed between the *** of gut microbiota diversity revealed lowerα-diversity in obese *** in gut microbiota composition were found between the two *** and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control *** To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood *** Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,*** information was collected through questionnaires and body measurements were obtained from both obese and normal-weight *** samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity *** Significant differences in BMI and body-fat percentage were observed between the two *** Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson ***-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggest

关键词： Childhood obesity Gut microbiota 16S rDNA sequencing Diversity analysis Genus identification Body mass index

Precision targeting in hepatocellular carcinoma:Exploring ligandreceptor mediated nanotherapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Hepatology 2024年第2期16卷 164-176页

作者： Xia-qing Zhou ya-Ping Li Shuang-Suo Dang Department of Infectious Diseases Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina

Hepatocellular carcinoma(HCC)is the most common primary liver cancer and poses a major challenge to global health due to its high morbidity and *** chemotherapy is usually targeted to patients with intermediate to advanced stages,but it is often ineffective and suffers from problems such as multidrug resistance,rapid drug clearance,nonspecific targeting,high side effects,and low drug accumulation in tumor *** response to these limitations,recent advances in nanoparticle-mediated targeted drug delivery technologies have emerged as breakthrough approaches for the treatment of *** review focuses on recent advances in nanoparticle-based targeted drug delivery systems,with special attention to various receptors overexpressed on HCC *** receptors are key to enhancing the specificity and efficacy of nanoparticle delivery and represent a new paradigm for actively targeting and combating *** comprehensively summarize the current understanding of these receptors,their role in nanoparticle targeting,and the impact of such targeted therapies on *** gaining a deeper understanding of the receptor-mediated mechanisms of these innovative therapies,more effective and precise treatment of HCC can be achieved.

关键词： Targeting Hepatocellular carcinoma Receptor Nanomedicine Chemotherapy

High-efficiency sodium storage of Co_(0.85)Se/WSe_(2) encapsulated in N-doped carbon polyhedron via vacancy and heterojunction engineering

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第1期6卷 94-107页

作者： ya Ru Pei Hong Yu Zhou Ming Zhao Jian Chen Li Xin Ge Wei Zhang Chun Cheng yang qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchunChina Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials Electron Microscopy CenterJilin UniversityChangchunChina

With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage ***,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+***,their synchronous engineering is rarely ***,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization *** aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se *** functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,*** expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides.

关键词： Co_(0.85)Se/WSe_(2)heterostructure density functional theory simulations N-doped carbon polyhedron Se vacancies sodium-ion batteries